API Reference¶

Top-Level Objects¶

class altair.Chart(data=Undefined, encoding=Undefined, mark=Undefined, width=Undefined, height=Undefined, **kwargs)¶

Create a basic Altair/Vega-Lite chart.

Although it is possible to set all Chart properties as constructor attributes, it is more idiomatic to use methods such as mark_point(), encode(), transform_filter(), properties(), etc. See Altair’s documentation for details and examples: http://altair-viz.github.io/.

Attributes:

data : Data

An object describing the data source

mark : AnyMark

A string describing the mark type (one of “bar”, “circle”, “square”, “tick”,: “line”, * “area”, “point”, “rule”, “geoshape”, and “text”) or a MarkDef object.

encoding : EncodingWithFacet

A key-value mapping between encoding channels and definition of fields.

autosize : anyOf(AutosizeType, AutoSizeParams)

Sets how the visualization size should be determined. If a string, should be one of “pad”, “fit” or “none”. Object values can additionally specify parameters for content sizing and automatic resizing. “fit” is only supported for single and layered views that don’t use rangeStep. __Default value__: pad

background : string

CSS color property to use as the background of visualization.

Default value: none (transparent)

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

description : string

Description of this mark for commenting purpose.

height : float

The height of a visualization.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {“left”: 5, “top”: 5, “right”: 5, “bottom”: 5} to specify padding for each side of the visualization. __Default value__: 5

projection : Projection

An object defining properties of geographic projection. Works with “geoshape” marks and “point” or “line” marks that have a channel (one or more of “X”, “X2”, “Y”, “Y2”) with type “latitude”, or “longitude”.

selection : Mapping(required=[])

A key-value mapping between selection names and definitions.

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

width : float

The width of a visualization.

facet(row=Undefined, column=Undefined, data=Undefined, **kwargs)¶

Create a facet chart from the current chart.

Faceted charts require data to be specified at the top level; if data is not specified, the data from the current chart will be used at the top level.

classmethod from_dict(dct, validate=True)¶

Construct class from a dictionary representation

Parameters:	dct : dictionary The dict from which to construct the class validate : boolean If True (default), then validate the input against the schema. _wrapper_classes : list (optional) The set of SchemaBase classes to use when constructing wrappers of the dict inputs. If not specified, the result of cls._default_wrapper_classes will be used.
Returns:	obj : Schema object The wrapped schema
Raises:	jsonschema.ValidationError : if validate=True and dct does not conform to the schema

interactive(name=None, bind_x=True, bind_y=True)¶

Make chart axes scales interactive

Parameters:	name : string The selection name to use for the axes scales. This name should be unique among all selections within the chart. bind_x : boolean, default True If true, then bind the interactive scales to the x-axis bind_y : boolean, default True If true, then bind the interactive scales to the y-axis
Returns:	chart : copy of self, with interactive axes added

class altair.LayerChart(data=Undefined, layer=(), **kwargs)¶

A Chart with layers within a single panel Mapping(required=[layer])

Attributes:

layer : List(anyOf(LayerSpec, CompositeUnitSpec))

Layer or single view specifications to be layered.

Note : Specifications inside layer cannot use row and column channels as layering facet specifications is not allowed.

autosize : anyOf(AutosizeType, AutoSizeParams)

Sets how the visualization size should be determined. If a string, should be one of "pad", "fit" or "none". Object values can additionally specify parameters for content sizing and automatic resizing. "fit" is only supported for single and layered views that don’t use rangeStep.

Default value : pad

background : string

CSS color property to use as the background of visualization.

Default value: none (transparent)

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

data : Data

An object describing the data source

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

description : string

Description of this mark for commenting purpose.

encoding : Encoding

A shared key-value mapping between encoding channels and definition of fields in the underlying layers.

height : float

The height of a visualization.

Default value:

If a view’s autosize type is "fit" or its y-channel has a continuous scale, the height will be the value of config.view.height.
For y-axis with a band or point scale: if rangeStep is a numeric value or unspecified, the height is determined by the range step, paddings, and the cardinality of the field mapped to y-channel. Otherwise, if the rangeStep is null, the height will be the value of config.view.height.
If no field is mapped to y channel, the height will be the value of rangeStep.

Note : For plots with row and column channels, this represents the height of a single view.

See also: The documentation for width and height contains more examples.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

projection : Projection

An object defining properties of the geographic projection shared by underlying layers.

resolve : Resolve

Scale, axis, and legend resolutions for layers.

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

width : float

The width of a visualization.

Default value: This will be determined by the following rules:

If a view’s autosize type is "fit" or its x-channel has a continuous scale, the width will be the value of config.view.width.
For x-axis with a band or point scale: if rangeStep is a numeric value or unspecified, the width is determined by the range step, paddings, and the cardinality of the field mapped to x-channel. Otherwise, if the rangeStep is null, the width will be the value of config.view.width.
If no field is mapped to x channel, the width will be the value of config.scale.textXRangeStep for text mark and the value of rangeStep for other marks.

Note: For plots with row and column channels, this represents the width of a single view.

See also: The documentation for width and height contains more examples.

$schema : string

URL to JSON schema for a Vega-Lite specification. Unless you have a reason to change this, use https://vega.github.io/schema/vega-lite/v2.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

facet(row=Undefined, column=Undefined, data=Undefined, **kwargs)¶

Create a facet chart from the current chart.

Faceted charts require data to be specified at the top level; if data is not specified, the data from the current chart will be used at the top level.

interactive(name=None, bind_x=True, bind_y=True)¶

Make chart axes scales interactive

Parameters:	name : string The selection name to use for the axes scales. This name should be unique among all selections within the chart. bind_x : boolean, default True If true, then bind the interactive scales to the x-axis bind_y : boolean, default True If true, then bind the interactive scales to the y-axis
Returns:	chart : copy of self, with interactive axes added

class altair.HConcatChart(data=Undefined, hconcat=(), **kwargs)¶

A chart with horizontally-concatenated facets: Mapping(required=[hconcat])

Attributes:

hconcat : List(Spec)

A list of views that should be concatenated and put into a row.

autosize : anyOf(AutosizeType, AutoSizeParams)

Sets how the visualization size should be determined. If a string, should be one of "pad", "fit" or "none". Object values can additionally specify parameters for content sizing and automatic resizing. "fit" is only supported for single and layered views that don’t use rangeStep.

Default value : pad

background : string

<<<<<<< HEAD

CSS color property to use as the background of visualization.

Default value: none (transparent)

=======

CSS color property to use as the background of visualization. Default value: none (transparent)

bounds : enum(‘full’, ‘flush’): The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"
center : boolean: Boolean flag indicating if subviews should be centered relative to their respective rows or columns. Default value: false

>>>>>>> altair-viz/master

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

data : Data

An object describing the data source

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

resolve : Resolve

Scale, axis, and legend resolutions for horizontally concatenated charts.

spacing : float

The spacing in pixels between sub-views of the concat operator. Default value :: 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

$schema : string

URL to JSON schema for a Vega-Lite specification. Unless you have a reason to change this, use https://vega.github.io/schema/vega-lite/v2.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

class altair.VConcatChart(data=Undefined, vconcat=(), **kwargs)¶

A chart with vertically-concatenated facets: Mapping(required=[vconcat])

Attributes:

vconcat : List(Spec)

A list of views that should be concatenated and put into a column.

autosize : anyOf(AutosizeType, AutoSizeParams)

Sets how the visualization size should be determined. If a string, should be one of "pad", "fit" or "none". Object values can additionally specify parameters for content sizing and automatic resizing. "fit" is only supported for single and layered views that don’t use rangeStep.

Default value : pad

background : string

<<<<<<< HEAD

CSS color property to use as the background of visualization.

Default value: none (transparent)

=======

CSS color property to use as the background of visualization. Default value: none (transparent)

bounds : enum(‘full’, ‘flush’): The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"
center : boolean: Boolean flag indicating if subviews should be centered relative to their respective rows or columns. Default value: false

>>>>>>> altair-viz/master

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

data : Data

An object describing the data source

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

resolve : Resolve

Scale, axis, and legend resolutions for vertically concatenated charts.

spacing : float

The spacing in pixels between sub-views of the concat operator. Default value :: 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

$schema : string

URL to JSON schema for a Vega-Lite specification. Unless you have a reason to change this, use https://vega.github.io/schema/vega-lite/v2.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

class altair.FacetChart(data=Undefined, spec=Undefined, facet=Undefined, **kwargs)¶

A Chart with layers within a single panel: Mapping(required=[data, facet, spec])

Attributes:

data : Data

An object describing the data source

facet : FacetMapping

An object that describes mappings between row and column channels and their field definitions.

spec : anyOf(LayerSpec, CompositeUnitSpec)

A specification of the view that gets faceted.

align : anyOf(VgLayoutAlign, RowColVgLayoutAlign)

The alignment to apply to grid rows and columns. The supported string values are "all", "each", and "none". * For "none", a flow layout will be used, in which adjacent subviews are simply placed one after the other. * For "each", subviews will be aligned into a clean grid structure, but each row or column may be of variable size. * For "all", subviews will be aligned and each row or column will be sized identically based on the maximum observed size. String values for this property will be applied to both grid rows and columns. Alternatively, an object value of the form {"row": string, "column": string} can

be used to supply different alignments for rows and columns. Default value:

"all".

autosize : anyOf(AutosizeType, AutoSizeParams)

Sets how the visualization size should be determined. If a string, should be one of "pad", "fit" or "none". Object values can additionally specify parameters for content sizing and automatic resizing. "fit" is only supported for single and layered views that don’t use rangeStep.

Default value : pad

background : string

<<<<<<< HEAD

CSS color property to use as the background of visualization.

Default value: none (transparent)

=======

CSS color property to use as the background of visualization. Default value: none (transparent)

bounds : enum(‘full’, ‘flush’): The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"
center : anyOf(boolean, RowColboolean): Boolean flag indicating if subviews should be centered relative to their respective rows or columns. An object value of the form {"row": boolean, "column": boolean} can be used to supply different centering values for rows and columns. Default value: false

>>>>>>> altair-viz/master

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

resolve : Resolve

Scale, axis, and legend resolutions for facets.

spacing : anyOf(float, RowColnumber)

The spacing in pixels between sub-views of the composition operator. An object of the form {"row": number, "column": number} can be used to set different spacing values for rows and columns. Default value : 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

$schema : string

URL to JSON schema for a Vega-Lite specification. Unless you have a reason to change this, use https://vega.github.io/schema/vega-lite/v2.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

interactive(name=None, bind_x=True, bind_y=True)¶

Make chart axes scales interactive

Parameters:	name : string The selection name to use for the axes scales. This name should be unique among all selections within the chart. bind_x : boolean, default True If true, then bind the interactive scales to the x-axis bind_y : boolean, default True If true, then bind the interactive scales to the y-axis
Returns:	chart : copy of self, with interactive axes added

class altair.RepeatChart(data=Undefined, spec=Undefined, repeat=Undefined, **kwargs)¶

A chart repeated across rows and columns with small changes: Mapping(required=[repeat, spec])

Attributes:

repeat : Repeat

Return a RepeatChart built from the chart

<<<<<<< HEAD

CSS color property to use as the background of visualization.

Default value: none (transparent)

=======

CSS color property to use as the background of visualization. Default value: none (transparent)

bounds : enum(‘full’, ‘flush’): The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"
center : anyOf(boolean, RowColboolean): Boolean flag indicating if subviews should be centered relative to their respective rows or columns. An object value of the form {"row": boolean, "column": boolean} can be used to supply different centering values for rows and columns. Default value: false

>>>>>>> altair-viz/master

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

data : Data

An object describing the data source

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

resolve : Resolve

Scale and legend resolutions for repeated charts.

spacing : anyOf(float, RowColnumber)

The spacing in pixels between sub-views of the composition operator. An object of the form {"row": number, "column": number} can be used to set different spacing values for rows and columns. Default value : 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

$schema : string

URL to JSON schema for a Vega-Lite specification. Unless you have a reason to change this, use https://vega.github.io/schema/vega-lite/v2.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

interactive(name=None, bind_x=True, bind_y=True)¶

Make chart axes scales interactive

Parameters:	name : string The selection name to use for the axes scales. This name should be unique among all selections within the chart. bind_x : boolean, default True If true, then bind the interactive scales to the x-axis bind_y : boolean, default True If true, then bind the interactive scales to the y-axis
Returns:	chart : copy of self, with interactive axes added

Encoding Channels¶

class altair.Color(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, legend=Undefined, scale=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Color schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

legend : anyOf(Legend, None)

An object defining properties of the legend. If null, the legend for the encoding channel will be removed.

Default value: If undefined, default legend properties are applied.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.ColorValue(value, condition=Undefined, **kwds)¶

ColorValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalMarkPropFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.Column(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, header=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Column schema wrapper

Mapping(required=[shorthand])

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

header : Header

An object defining properties of a facet’s header.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.Detail(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Detail schema wrapper

Mapping(required=[shorthand]) Definition object for a data field, its type and transformation of an encoding channel.

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.Href(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Href schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.HrefValue(value, condition=Undefined, **kwds)¶

HrefValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.Opacity(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, legend=Undefined, scale=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Opacity schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

legend : anyOf(Legend, None)

An object defining properties of the legend. If null, the legend for the encoding channel will be removed.

Default value: If undefined, default legend properties are applied.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.OpacityValue(value, condition=Undefined, **kwds)¶

OpacityValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalMarkPropFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.Order(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Order schema wrapper

Mapping(required=[shorthand])

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

sort : SortOrder

The sort order. One of "ascending" (default) or "descending".

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.Row(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, header=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Row schema wrapper

Mapping(required=[shorthand])

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

header : Header

An object defining properties of a facet’s header.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.Shape(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, legend=Undefined, scale=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Shape schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

legend : anyOf(Legend, None)

An object defining properties of the legend. If null, the legend for the encoding channel will be removed.

Default value: If undefined, default legend properties are applied.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.ShapeValue(value, condition=Undefined, **kwds)¶

ShapeValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalMarkPropFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.Size(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, legend=Undefined, scale=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Size schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

legend : anyOf(Legend, None)

An object defining properties of the legend. If null, the legend for the encoding channel will be removed.

Default value: If undefined, default legend properties are applied.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.SizeValue(value, condition=Undefined, **kwds)¶

SizeValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalMarkPropFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.Text(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, format=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Text schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

format : string

The formatting pattern for a text field. If not defined, this will be determined automatically.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.TextValue(value, condition=Undefined, **kwds)¶

TextValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalTextFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.Tooltip(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, format=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Tooltip schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

format : string

The formatting pattern for a text field. If not defined, this will be determined automatically.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.TooltipValue(value, condition=Undefined, **kwds)¶

TooltipValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalTextFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.X(shorthand=Undefined, aggregate=Undefined, axis=Undefined, bin=Undefined, field=Undefined, scale=Undefined, sort=Undefined, stack=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

X schema wrapper

Mapping(required=[shorthand])

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

axis : anyOf(Axis, None)

An object defining properties of axis’s gridlines, ticks and labels. If null, the axis for the encoding channel will be removed.

Default value: If undefined, default axis properties are applied.

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

stack : anyOf(StackOffset, None)

Type of stacking offset if the field should be stacked. stack is only applicable for x and y channels with continuous domains. For example, stack of y can be used to customize stacking for a vertical bar chart.

stack can be one of the following values:

“zero”: stacking with baseline offset at zero value of the scale (for creating typical stacked [bar](https://vega.github.io/vega-lite/docs/stack.html#bar) and area chart).
"normalize" - stacking with normalized domain (for creating normalized stacked bar and area charts.

"center" - stacking with center baseline (for `streamgraph

<https://vega.github.io/vega-lite/docs/stack.html#streamgraph>`_ ). * null - No-stacking. This will produce layered `bar

<https://vega.github.io/vega-lite/docs/stack.html#layered-bar-chart>`_ and area chart.

Default value: zero for plots with all of the following conditions are true: (1) the mark is bar or area ; (2) the stacked measure channel (x or y) has a linear scale; (3) At least one of non-position channels mapped to an unaggregated field that is different from x and y. Otherwise, null by default.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.XValue(value, **kwds)¶

XValue schema wrapper

Mapping(required=[value]) Definition object for a constant value of an encoding channel.

Attributes:	value : anyOf(float, string, boolean) A constant value in visual domain (e.g., `"red"` / “#0099ff” for color, values between `0` to `1` for opacity).

class altair.X2(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

X2 schema wrapper

Mapping(required=[shorthand]) Definition object for a data field, its type and transformation of an encoding channel.

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.X2Value(value, **kwds)¶

X2Value schema wrapper

Mapping(required=[value]) Definition object for a constant value of an encoding channel.

Attributes:	value : anyOf(float, string, boolean) A constant value in visual domain (e.g., `"red"` / “#0099ff” for color, values between `0` to `1` for opacity).

class altair.Y(shorthand=Undefined, aggregate=Undefined, axis=Undefined, bin=Undefined, field=Undefined, scale=Undefined, sort=Undefined, stack=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Y schema wrapper

Mapping(required=[shorthand])

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

axis : anyOf(Axis, None)

An object defining properties of axis’s gridlines, ticks and labels. If null, the axis for the encoding channel will be removed.

Default value: If undefined, default axis properties are applied.

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

stack : anyOf(StackOffset, None)

Type of stacking offset if the field should be stacked. stack is only applicable for x and y channels with continuous domains. For example, stack of y can be used to customize stacking for a vertical bar chart.

stack can be one of the following values:

“zero”: stacking with baseline offset at zero value of the scale (for creating typical stacked [bar](https://vega.github.io/vega-lite/docs/stack.html#bar) and area chart).
"normalize" - stacking with normalized domain (for creating normalized stacked bar and area charts.

"center" - stacking with center baseline (for `streamgraph

<https://vega.github.io/vega-lite/docs/stack.html#streamgraph>`_ ). * null - No-stacking. This will produce layered `bar

<https://vega.github.io/vega-lite/docs/stack.html#layered-bar-chart>`_ and area chart.

Default value: zero for plots with all of the following conditions are true: (1) the mark is bar or area ; (2) the stacked measure channel (x or y) has a linear scale; (3) At least one of non-position channels mapped to an unaggregated field that is different from x and y. Otherwise, null by default.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.YValue(value, **kwds)¶

YValue schema wrapper

Mapping(required=[value]) Definition object for a constant value of an encoding channel.

Attributes:	value : anyOf(float, string, boolean) A constant value in visual domain (e.g., `"red"` / “#0099ff” for color, values between `0` to `1` for opacity).

class altair.Y2(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Y2 schema wrapper

Mapping(required=[shorthand]) Definition object for a data field, its type and transformation of an encoding channel.

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.Y2Value(value, **kwds)¶

Y2Value schema wrapper

Mapping(required=[value]) Definition object for a constant value of an encoding channel.

Attributes:	value : anyOf(float, string, boolean) A constant value in visual domain (e.g., `"red"` / “#0099ff” for color, values between `0` to `1` for opacity).

Other Objects¶

exception altair.MaxRowsError¶: Raised when a data model has too many rows.

class altair.Aggregate(*args)¶

Aggregate schema wrapper

enum(‘argmax’, ‘argmin’, ‘average’, ‘count’, ‘distinct’, ‘max’, ‘mean’, ‘median’, ‘min’, ‘missing’, ‘q1’, ‘q3’, ‘ci0’, ‘ci1’, ‘stderr’, ‘stdev’, ‘stdevp’, ‘sum’, ‘valid’, ‘values’, ‘variance’, ‘variancep’)

class altair.AggregateOp(*args)¶

AggregateOp schema wrapper

enum(‘argmax’, ‘argmin’, ‘average’, ‘count’, ‘distinct’, ‘max’, ‘mean’, ‘median’, ‘min’, ‘missing’, ‘q1’, ‘q3’, ‘ci0’, ‘ci1’, ‘stderr’, ‘stdev’, ‘stdevp’, ‘sum’, ‘valid’, ‘values’, ‘variance’, ‘variancep’)

class altair.AggregateTransform(aggregate=Undefined, groupby=Undefined, **kwds)¶

AggregateTransform schema wrapper

Mapping(required=[aggregate])

Attributes:	aggregate : List(AggregatedFieldDef) Array of objects that define fields to aggregate. groupby : List(string) The data fields to group by. If not specified, a single group containing all data objects will be used.

class altair.AggregatedFieldDef(op=Undefined, field=Undefined, **kwds)¶

AggregatedFieldDef schema wrapper

Mapping(required=[op, as])

Attributes:	op : AggregateOp The aggregation operations to apply to the fields, such as sum, average or count. See the full list of supported aggregation operations for more information. field : string The data field for which to compute aggregate function. This is required for all aggregation operations except `"count"`. as : string The output field names to use for each aggregated field.

class altair.Anchor(*args)¶

Anchor schema wrapper

enum(‘start’, ‘middle’, ‘end’)

class altair.AnyMark(*args, **kwds)¶

AnyMark schema wrapper

anyOf(Mark, MarkDef)

class altair.AreaConfig(align=Undefined, angle=Undefined, baseline=Undefined, color=Undefined, cornerRadius=Undefined, cursor=Undefined, dir=Undefined, dx=Undefined, dy=Undefined, ellipsis=Undefined, fill=Undefined, fillOpacity=Undefined, filled=Undefined, font=Undefined, fontSize=Undefined, fontStyle=Undefined, fontWeight=Undefined, href=Undefined, interpolate=Undefined, limit=Undefined, line=Undefined, opacity=Undefined, orient=Undefined, point=Undefined, radius=Undefined, shape=Undefined, size=Undefined, stroke=Undefined, strokeCap=Undefined, strokeDash=Undefined, strokeDashOffset=Undefined, strokeJoin=Undefined, strokeMiterLimit=Undefined, strokeOpacity=Undefined, strokeWidth=Undefined, tension=Undefined, text=Undefined, theta=Undefined, tooltip=Undefined, **kwds)¶

AreaConfig schema wrapper

Mapping(required=[])

Attributes:

align : HorizontalAlign

The horizontal alignment of the text. One of "left", "right", "center".

angle : float

The rotation angle of the text, in degrees.

baseline : VerticalAlign

The vertical alignment of the text. One of "top", "middle", "bottom".

Default value: "middle"

color : string

Default color. Note that fill and stroke have higher precedence than color and will override color.

Default value: ■ "#4682b4"

Note: This property cannot be used in a style config.

cornerRadius : float

The radius in pixels of rounded rectangle corners. Default value: 0

cursor : Cursor

The mouse cursor used over the mark. Any valid CSS cursor type can be used.

dir : Dir

The direction of the text. One of "ltr" (left-to-right) or "rtl" (right-to-left). This property determines on which side is truncated in response to the limit parameter. Default value: "ltr"

dx : float

The horizontal offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

dy : float

The vertical offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

ellipsis : string

The ellipsis string for text truncated in response to the limit parameter. Default value: "…"

fill : string

Default Fill Color. This has higher precedence than config.color

Default value: (None)

fillOpacity : float

The fill opacity (value between [0,1]).

Default value: 1

filled : boolean

Whether the mark’s color should be used as fill color instead of stroke color.

Default value: true for all marks except point and false for point.

Applicable for: bar, point, circle, square, and area marks.

Note: This property cannot be used in a style config.

font : string

The typeface to set the text in (e.g., "Helvetica Neue" ).

fontSize : float

The font size, in pixels.

fontStyle : FontStyle

The font style (e.g., "italic" ).

fontWeight : FontWeight

The font weight. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

href : string

A URL to load upon mouse click. If defined, the mark acts as a hyperlink.

interpolate : Interpolate

The line interpolation method to use for line and area marks. One of the following:

"linear" : piecewise linear segments, as in a polyline.
"linear-closed" : close the linear segments to form a polygon.
"step" : alternate between horizontal and vertical segments, as in a step function.
"step-before" : alternate between vertical and horizontal segments, as in a step function.
"step-after" : alternate between horizontal and vertical segments, as in a step function.
"basis" : a B-spline, with control point duplication on the ends.
"basis-open" : an open B-spline; may not intersect the start or end.
"basis-closed" : a closed B-spline, as in a loop.
"cardinal" : a Cardinal spline, with control point duplication on the ends.
"cardinal-open" : an open Cardinal spline; may not intersect the start or end, but will intersect other control points.
"cardinal-closed" : a closed Cardinal spline, as in a loop.
"bundle" : equivalent to basis, except the tension parameter is used to straighten the spline.
"monotone" : cubic interpolation that preserves monotonicity in y.

limit : float

The maximum length of the text mark in pixels. The text value will be automatically truncated if the rendered size exceeds the limit. Default value: 0, indicating no limit

line : anyOf(boolean, OverlayMarkDef)

A flag for overlaying line on top of area marks, or an object defining the properties of the overlayed lines.

If this value is an empty object ( {} ) or true, lines with default properties will be used.

If this value is false, no lines would be automatically added to area marks.

Default value: false.

opacity : float

The overall opacity (value between [0,1]).

Default value: 0.7 for non-aggregate plots with point, tick, circle, or square marks or layered bar charts and 1 otherwise.

orient : Orient

The orientation of a non-stacked bar, tick, area, and line charts. The value is either horizontal (default) or vertical.

For bar, rule and tick, this determines whether the size of the bar and tick

should be applied to x or y dimension. * For area, this property determines the orient property of the Vega output. * For line and trail marks, this property determines the sort order of the points in

the line

if config.sortLineBy is not specified. For stacked charts, this is always determined by the orientation of the stack; therefore explicitly specified value will be ignored.

point : anyOf(boolean, MarkConfig, enum(‘transparent’))

A flag for overlaying points on top of line or area marks, or an object defining the properties of the overlayed points.

If this property is "transparent", transparent points will be used (for enhancing tooltips and selections).

If this property is an empty object ( {} ) or true, filled points with default properties will be used.

If this property is false, no points would be automatically added to line or area marks.

Default value: false.

radius : float

Polar coordinate radial offset, in pixels, of the text label from the origin determined by the x and y properties.

shape : string

The default symbol shape to use. One of: "circle" (default), "square", "cross", "diamond", "triangle-up", or "triangle-down", or a custom SVG path.

Default value: "circle"

size : float

The pixel area each the point/circle/square. For example: in the case of circles, the radius is determined in part by the square root of the size value.

Default value: 30

stroke : string

Default Stroke Color. This has higher precedence than config.color

Default value: (None)

strokeCap : enum(‘butt’, ‘round’, ‘square’)

The stroke cap for line ending style. One of "butt", "round", or "square".

Default value: "square"

strokeDash : List(float)

An array of alternating stroke, space lengths for creating dashed or dotted lines.

strokeDashOffset : float

The offset (in pixels) into which to begin drawing with the stroke dash array.

strokeJoin : StrokeJoin

The stroke line join method. One of "miter", "round" or "bevel". Default value: "miter"

strokeMiterLimit : float

The miter limit at which to bevel a line join.

strokeOpacity : float

The stroke opacity (value between [0,1]).

Default value: 1

strokeWidth : float

The stroke width, in pixels.

tension : float

Depending on the interpolation type, sets the tension parameter (for line and area marks).

text : string

Placeholder text if the text channel is not specified

theta : float

Polar coordinate angle, in radians, of the text label from the origin determined by the x and y properties. Values for theta follow the same convention of arc mark startAngle and endAngle properties: angles are measured in radians, with 0 indicating “north”.

tooltip : Mapping(required=[])

The tooltip text to show upon mouse hover.

class altair.AutoSizeParams(contains=Undefined, resize=Undefined, type=Undefined, **kwds)¶

AutoSizeParams schema wrapper

Mapping(required=[])

Attributes:

contains : enum(‘content’, ‘padding’)

Determines how size calculation should be performed, one of "content" or "padding". The default setting ( "content" ) interprets the width and height settings as the data rectangle (plotting) dimensions, to which padding is then added. In contrast, the "padding" setting includes the padding within the view size calculations, such that the width and height settings indicate the total intended size of the view.

Default value : "content"

resize : boolean

A boolean flag indicating if autosize layout should be re-calculated on every view update.

Default value : false

type : AutosizeType

The sizing format type. One of "pad", "fit" or "none". See the autosize type documentation for descriptions of each.

Default value : "pad"

class altair.AutosizeType(*args)¶

AutosizeType schema wrapper

enum(‘pad’, ‘fit’, ‘none’)

class altair.Axis(domain=Undefined, format=Undefined, grid=Undefined, labelAngle=Undefined, labelBound=Undefined, labelFlush=Undefined, labelOverlap=Undefined, labelPadding=Undefined, labels=Undefined, maxExtent=Undefined, minExtent=Undefined, offset=Undefined, orient=Undefined, position=Undefined, tickCount=Undefined, tickSize=Undefined, ticks=Undefined, title=Undefined, titleMaxLength=Undefined, titlePadding=Undefined, values=Undefined, zindex=Undefined, **kwds)¶

Axis schema wrapper

Mapping(required=[])

Attributes:

domain : boolean

A boolean flag indicating if the domain (the axis baseline) should be included as part of the axis.

Default value: true

format : string

The formatting pattern for labels. This is D3’s number format pattern for quantitative fields and D3’s time format pattern for time field.

See the format documentation for more information.

Default value: derived from numberFormat config for quantitative fields and from timeFormat config for temporal fields.

grid : boolean

A boolean flag indicating if grid lines should be included as part of the axis

Default value: true for continuous scales that are not binned; otherwise, false.

labelAngle : float

The rotation angle of the axis labels.

Default value: -90 for nominal and ordinal fields; 0 otherwise.

labelBound : anyOf(boolean, float)

Indicates if labels should be hidden if they exceed the axis range. If false (the default) no bounds overlap analysis is performed. If true, labels will be hidden if they exceed the axis range by more than 1 pixel. If this property is a number, it specifies the pixel tolerance: the maximum amount by which a label bounding box may exceed the axis range.

Default value: false.

labelFlush : anyOf(boolean, float)

Indicates if the first and last axis labels should be aligned flush with the scale range. Flush alignment for a horizontal axis will left-align the first label and right-align the last label. For vertical axes, bottom and top text baselines are applied instead. If this property is a number, it also indicates the number of pixels by which to offset the first and last labels; for example, a value of 2 will flush-align the first and last labels and also push them 2 pixels outward from the center of the axis. The additional adjustment can sometimes help the labels better visually group with corresponding axis ticks.

Default value: true for axis of a continuous x-scale. Otherwise, false.

labelOverlap : anyOf(boolean, enum(‘parity’), enum(‘greedy’))

The strategy to use for resolving overlap of axis labels. If false (the default), no overlap reduction is attempted. If set to true or "parity", a strategy of removing every other label is used (this works well for standard linear axes). If set to "greedy", a linear scan of the labels is performed, removing any labels that overlaps with the last visible label (this often works better for log-scaled axes).

Default value: true for non-nominal fields with non-log scales; "greedy" for log scales; otherwise false.

labelPadding : float

The padding, in pixels, between axis and text labels.

labels : boolean

A boolean flag indicating if labels should be included as part of the axis.

Default value: true.

maxExtent : float

The maximum extent in pixels that axis ticks and labels should use. This determines a maximum offset value for axis titles.

Default value: undefined.

minExtent : float

The minimum extent in pixels that axis ticks and labels should use. This determines a minimum offset value for axis titles.

Default value: 30 for y-axis; undefined for x-axis.

offset : float

The offset, in pixels, by which to displace the axis from the edge of the enclosing group or data rectangle.

Default value: derived from the axis config ‘s offset ( 0 by default)

orient : AxisOrient

The orientation of the axis. One of "top", "bottom", "left" or "right". The orientation can be used to further specialize the axis type (e.g., a y axis oriented for the right edge of the chart).

Default value: "bottom" for x-axes and "left" for y-axes.

position : float

The anchor position of the axis in pixels. For x-axis with top or bottom orientation, this sets the axis group x coordinate. For y-axis with left or right orientation, this sets the axis group y coordinate.

Default value : 0

tickCount : float

A desired number of ticks, for axes visualizing quantitative scales. The resulting number may be different so that values are “nice” (multiples of 2, 5, 10) and lie within the underlying scale’s range.

tickSize : float

The size in pixels of axis ticks.

ticks : boolean

Boolean value that determines whether the axis should include ticks.

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

titleMaxLength : float

Max length for axis title if the title is automatically generated from the field’s description.

titlePadding : float

The padding, in pixels, between title and axis.

values : anyOf(List(float), List(string), List(boolean), List(DateTime))

Explicitly set the visible axis tick values.

zindex : float

A non-positive integer indicating z-index of the axis. If zindex is 0, axes should be drawn behind all chart elements. To put them in front, use "zindex = 1".

Default value: 1 (in front of the marks) for actual axis and 0 (behind the marks) for grids.

class altair.AxisConfig(bandPosition=Undefined, domain=Undefined, domainColor=Undefined, domainWidth=Undefined, grid=Undefined, gridColor=Undefined, gridDash=Undefined, gridOpacity=Undefined, gridWidth=Undefined, labelAngle=Undefined, labelBound=Undefined, labelColor=Undefined, labelFlush=Undefined, labelFont=Undefined, labelFontSize=Undefined, labelLimit=Undefined, labelOverlap=Undefined, labelPadding=Undefined, labels=Undefined, maxExtent=Undefined, minExtent=Undefined, shortTimeLabels=Undefined, tickColor=Undefined, tickRound=Undefined, tickSize=Undefined, tickWidth=Undefined, ticks=Undefined, titleAlign=Undefined, titleAngle=Undefined, titleBaseline=Undefined, titleColor=Undefined, titleFont=Undefined, titleFontSize=Undefined, titleFontWeight=Undefined, titleLimit=Undefined, titleMaxLength=Undefined, titlePadding=Undefined, titleX=Undefined, titleY=Undefined, **kwds)¶

AxisConfig schema wrapper

Mapping(required=[])

Attributes:

bandPosition : float

An interpolation fraction indicating where, for band scales, axis ticks should be positioned. A value of 0 places ticks at the left edge of their bands. A value of 0.5 places ticks in the middle of their bands.

domain : boolean

A boolean flag indicating if the domain (the axis baseline) should be included as part of the axis.

Default value: true

domainColor : string

Color of axis domain line.

Default value: (none, using Vega default).

domainWidth : float

Stroke width of axis domain line

Default value: (none, using Vega default).

grid : boolean

A boolean flag indicating if grid lines should be included as part of the axis

Default value: true for continuous scales that are not binned; otherwise, false.

gridColor : string

Color of gridlines.

gridDash : List(float)

The offset (in pixels) into which to begin drawing with the grid dash array.

gridOpacity : float

The stroke opacity of grid (value between [0,1])

Default value: ( 1 by default)

gridWidth : float

The grid width, in pixels.

labelAngle : float

The rotation angle of the axis labels.

Default value: -90 for nominal and ordinal fields; 0 otherwise.

labelBound : anyOf(boolean, float)

Indicates if labels should be hidden if they exceed the axis range. If false (the default) no bounds overlap analysis is performed. If true, labels will be hidden if they exceed the axis range by more than 1 pixel. If this property is a number, it specifies the pixel tolerance: the maximum amount by which a label bounding box may exceed the axis range.

Default value: false.

labelColor : string

The color of the tick label, can be in hex color code or regular color name.

labelFlush : anyOf(boolean, float)

Indicates if the first and last axis labels should be aligned flush with the scale range. Flush alignment for a horizontal axis will left-align the first label and right-align the last label. For vertical axes, bottom and top text baselines are applied instead. If this property is a number, it also indicates the number of pixels by which to offset the first and last labels; for example, a value of 2 will flush-align the first and last labels and also push them 2 pixels outward from the center of the axis. The additional adjustment can sometimes help the labels better visually group with corresponding axis ticks.

Default value: true for axis of a continuous x-scale. Otherwise, false.

labelFont : string

The font of the tick label.

labelFontSize : float

The font size of the label, in pixels.

labelLimit : float

Maximum allowed pixel width of axis tick labels.

labelOverlap : anyOf(boolean, enum(‘parity’), enum(‘greedy’))

The strategy to use for resolving overlap of axis labels. If false (the default), no overlap reduction is attempted. If set to true or "parity", a strategy of removing every other label is used (this works well for standard linear axes). If set to "greedy", a linear scan of the labels is performed, removing any labels that overlaps with the last visible label (this often works better for log-scaled axes).

Default value: true for non-nominal fields with non-log scales; "greedy" for log scales; otherwise false.

labelPadding : float

The padding, in pixels, between axis and text labels.

labels : boolean

A boolean flag indicating if labels should be included as part of the axis.

Default value: true.

maxExtent : float

The maximum extent in pixels that axis ticks and labels should use. This determines a maximum offset value for axis titles.

Default value: undefined.

minExtent : float

The minimum extent in pixels that axis ticks and labels should use. This determines a minimum offset value for axis titles.

Default value: 30 for y-axis; undefined for x-axis.

shortTimeLabels : boolean

Whether month names and weekday names should be abbreviated.

Default value: false

tickColor : string

The color of the axis’s tick.

tickRound : boolean

Boolean flag indicating if pixel position values should be rounded to the nearest integer.

tickSize : float

The size in pixels of axis ticks.

tickWidth : float

The width, in pixels, of ticks.

ticks : boolean

Boolean value that determines whether the axis should include ticks.

titleAlign : string

Horizontal text alignment of axis titles.

titleAngle : float

Angle in degrees of axis titles.

titleBaseline : string

Vertical text baseline for axis titles.

titleColor : string

Color of the title, can be in hex color code or regular color name.

titleFont : string

Font of the title. (e.g., "Helvetica Neue" ).

titleFontSize : float

Font size of the title.

titleFontWeight : FontWeight

Font weight of the title. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

titleLimit : float

Maximum allowed pixel width of axis titles.

titleMaxLength : float

Max length for axis title if the title is automatically generated from the field’s description.

titlePadding : float

The padding, in pixels, between title and axis.

titleX : float

X-coordinate of the axis title relative to the axis group.

titleY : float

Y-coordinate of the axis title relative to the axis group.

class altair.AxisOrient(*args)¶

AxisOrient schema wrapper

enum(‘top’, ‘right’, ‘left’, ‘bottom’)

class altair.AxisResolveMap(x=Undefined, y=Undefined, **kwds)¶

AxisResolveMap schema wrapper

Mapping(required=[])

Attributes:	x : ResolveMode y : ResolveMode

class altair.BarConfig(align=Undefined, angle=Undefined, baseline=Undefined, binSpacing=Undefined, color=Undefined, continuousBandSize=Undefined, cornerRadius=Undefined, cursor=Undefined, dir=Undefined, discreteBandSize=Undefined, dx=Undefined, dy=Undefined, ellipsis=Undefined, fill=Undefined, fillOpacity=Undefined, filled=Undefined, font=Undefined, fontSize=Undefined, fontStyle=Undefined, fontWeight=Undefined, href=Undefined, interpolate=Undefined, limit=Undefined, opacity=Undefined, orient=Undefined, radius=Undefined, shape=Undefined, size=Undefined, stroke=Undefined, strokeCap=Undefined, strokeDash=Undefined, strokeDashOffset=Undefined, strokeJoin=Undefined, strokeMiterLimit=Undefined, strokeOpacity=Undefined, strokeWidth=Undefined, tension=Undefined, text=Undefined, theta=Undefined, tooltip=Undefined, **kwds)¶

BarConfig schema wrapper

Mapping(required=[])

Attributes:

align : HorizontalAlign

The horizontal alignment of the text. One of "left", "right", "center".

angle : float

The rotation angle of the text, in degrees.

baseline : VerticalAlign

The vertical alignment of the text. One of "top", "middle", "bottom".

Default value: "middle"

binSpacing : float

Offset between bars for binned field. Ideal value for this is either 0 (Preferred by statisticians) or 1 (Vega-Lite Default, D3 example style).

Default value: 1

color : string

Default color. Note that fill and stroke have higher precedence than color and will override color.

Default value: ■ "#4682b4"

Note: This property cannot be used in a style config.

continuousBandSize : float

The default size of the bars on continuous scales. Default value: 5

cornerRadius : float

The radius in pixels of rounded rectangle corners. Default value: 0

cursor : Cursor

The mouse cursor used over the mark. Any valid CSS cursor type can be used.

dir : Dir

The direction of the text. One of "ltr" (left-to-right) or "rtl" (right-to-left). This property determines on which side is truncated in response to the limit parameter. Default value: "ltr"

discreteBandSize : float

The size of the bars. If unspecified, the default size is bandSize-1, which provides 1 pixel offset between bars.

dx : float

The horizontal offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

dy : float

The vertical offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

ellipsis : string

The ellipsis string for text truncated in response to the limit parameter. Default value: "…"

fill : string

Default Fill Color. This has higher precedence than config.color

Default value: (None)

fillOpacity : float

The fill opacity (value between [0,1]).

Default value: 1

filled : boolean

Whether the mark’s color should be used as fill color instead of stroke color.

Default value: true for all marks except point and false for point.

Applicable for: bar, point, circle, square, and area marks.

Note: This property cannot be used in a style config.

font : string

The typeface to set the text in (e.g., "Helvetica Neue" ).

fontSize : float

The font size, in pixels.

fontStyle : FontStyle

The font style (e.g., "italic" ).

fontWeight : FontWeight

The font weight. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

href : string

A URL to load upon mouse click. If defined, the mark acts as a hyperlink.

interpolate : Interpolate

The line interpolation method to use for line and area marks. One of the following:

"linear" : piecewise linear segments, as in a polyline.
"linear-closed" : close the linear segments to form a polygon.
"step" : alternate between horizontal and vertical segments, as in a step function.
"step-before" : alternate between vertical and horizontal segments, as in a step function.
"step-after" : alternate between horizontal and vertical segments, as in a step function.
"basis" : a B-spline, with control point duplication on the ends.
"basis-open" : an open B-spline; may not intersect the start or end.
"basis-closed" : a closed B-spline, as in a loop.
"cardinal" : a Cardinal spline, with control point duplication on the ends.
"cardinal-open" : an open Cardinal spline; may not intersect the start or end, but will intersect other control points.
"cardinal-closed" : a closed Cardinal spline, as in a loop.
"bundle" : equivalent to basis, except the tension parameter is used to straighten the spline.
"monotone" : cubic interpolation that preserves monotonicity in y.

limit : float

The maximum length of the text mark in pixels. The text value will be automatically truncated if the rendered size exceeds the limit. Default value: 0, indicating no limit

opacity : float

The overall opacity (value between [0,1]).

Default value: 0.7 for non-aggregate plots with point, tick, circle, or square marks or layered bar charts and 1 otherwise.

orient : Orient

The orientation of a non-stacked bar, tick, area, and line charts. The value is either horizontal (default) or vertical.

For bar, rule and tick, this determines whether the size of the bar and tick

should be applied to x or y dimension. * For area, this property determines the orient property of the Vega output. * For line and trail marks, this property determines the sort order of the points in

the line

if config.sortLineBy is not specified. For stacked charts, this is always determined by the orientation of the stack; therefore explicitly specified value will be ignored.

radius : float

Polar coordinate radial offset, in pixels, of the text label from the origin determined by the x and y properties.

shape : string

The default symbol shape to use. One of: "circle" (default), "square", "cross", "diamond", "triangle-up", or "triangle-down", or a custom SVG path.

Default value: "circle"

size : float

The pixel area each the point/circle/square. For example: in the case of circles, the radius is determined in part by the square root of the size value.

Default value: 30

stroke : string

<<<<<<< HEAD

Default Stroke Color. This has higher precedence than config.color

Default value: (None)

strokeCap : enum(‘butt’, ‘round’, ‘square’)

=======

Default Stroke Color. This has higher precedence than config.color Default value: (None)

strokeCap : StrokeCap

>>>>>>> altair-viz/master

The stroke cap for line ending style. One of "butt", "round", or "square".

Default value: "square"

strokeDash : List(float)

An array of alternating stroke, space lengths for creating dashed or dotted lines.

strokeDashOffset : float

The offset (in pixels) into which to begin drawing with the stroke dash array.

strokeJoin : StrokeJoin

The stroke line join method. One of "miter", "round" or "bevel". Default value: "miter"

strokeMiterLimit : float

The miter limit at which to bevel a line join.

strokeOpacity : float

The stroke opacity (value between [0,1]).

Default value: 1

strokeWidth : float

The stroke width, in pixels.

tension : float

Depending on the interpolation type, sets the tension parameter (for line and area marks).

text : string

Placeholder text if the text channel is not specified

theta : float

Polar coordinate angle, in radians, of the text label from the origin determined by the x and y properties. Values for theta follow the same convention of arc mark startAngle and endAngle properties: angles are measured in radians, with 0 indicating “north”.

tooltip : Mapping(required=[])

The tooltip text to show upon mouse hover.

class altair.Baseline(*args)¶

Baseline schema wrapper

enum(‘top’, ‘middle’, ‘bottom’)

class altair.BasicType(*args)¶

BasicType schema wrapper

enum(‘quantitative’, ‘ordinal’, ‘temporal’, ‘nominal’)

altair.Bin¶: alias of altair.vegalite.v2.schema.core.BinParams

class altair.BinParams(anchor=Undefined, base=Undefined, divide=Undefined, extent=Undefined, maxbins=Undefined, minstep=Undefined, nice=Undefined, step=Undefined, steps=Undefined, **kwds)¶

BinParams schema wrapper

Mapping(required=[]) Binning properties or boolean flag for determining whether to bin data or not.

Attributes:

<<<<<<< HEAD

=======

anchor : float: A value in the binned domain at which to anchor the bins, shifting the bin boundaries if necessary to ensure that a boundary aligns with the anchor value. Default Value: the minimum bin extent value

>>>>>>> altair-viz/master

base : float

The number base to use for automatic bin determination (default is base 10).

Default value: 10

divide : List(float)

Scale factors indicating allowable subdivisions. The default value is [5, 2], which indicates that for base 10 numbers (the default base), the method may consider dividing bin sizes by 5 and/or 2. For example, for an initial step size of 10, the method can check if bin sizes of 2 (= 10/5), 5 (= 10/2), or 1 (= 10/(5*2)) might also satisfy the given constraints.

Default value: [5, 2]

extent : List(float)

A two-element ( [min, max] ) array indicating the range of desired bin values.

maxbins : float

Maximum number of bins.

Default value: 6 for row, column and shape channels; 10 for other channels

minstep : float

A minimum allowable step size (particularly useful for integer values).

nice : boolean

If true (the default), attempts to make the bin boundaries use human-friendly boundaries, such as multiples of ten.

step : float

An exact step size to use between bins.

Note: If provided, options such as maxbins will be ignored.

steps : List(float)

An array of allowable step sizes to choose from.

class altair.BinTransform(bin=Undefined, field=Undefined, **kwds)¶

BinTransform schema wrapper

Mapping(required=[bin, field, as])

Attributes:	bin : anyOf(boolean, BinParams) An object indicating bin properties, or simply `true` for using default bin parameters. field : string The data field to bin. as : anyOf(string, List(string)) The output fields at which to write the start and end bin values.

class altair.BrushConfig(fill=Undefined, fillOpacity=Undefined, stroke=Undefined, strokeDash=Undefined, strokeDashOffset=Undefined, strokeOpacity=Undefined, strokeWidth=Undefined, **kwds)¶

BrushConfig schema wrapper

Mapping(required=[])

Attributes:

fill : string

The fill color of the interval mark.

Default value: #333333

fillOpacity : float

The fill opacity of the interval mark (a value between 0 and 1).

Default value: 0.125

stroke : string

The stroke color of the interval mark.

Default value: #ffffff

strokeDash : List(float)

An array of alternating stroke and space lengths, for creating dashed or dotted lines.

strokeDashOffset : float

The offset (in pixels) with which to begin drawing the stroke dash array.

strokeOpacity : float

The stroke opacity of the interval mark (a value between 0 and 1).

strokeWidth : float

The stroke width of the interval mark.

class altair.CalculateTransform(calculate=Undefined, **kwds)¶

CalculateTransform schema wrapper

Mapping(required=[calculate, as])

Attributes:	calculate : string A expression string. Use the variable `datum` to refer to the current data object. as : string The field for storing the computed formula value.

class altair.Color(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, legend=Undefined, scale=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

Color schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

legend : anyOf(Legend, None)

An object defining properties of the legend. If null, the legend for the encoding channel will be removed.

Default value: If undefined, default legend properties are applied.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.ColorValue(value, condition=Undefined, **kwds)

ColorValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalMarkPropFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.Column(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, header=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

Column schema wrapper

Mapping(required=[shorthand])

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

header : Header

An object defining properties of a facet’s header.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.CompositeUnitSpec(mark=Undefined, data=Undefined, description=Undefined, encoding=Undefined, height=Undefined, name=Undefined, projection=Undefined, selection=Undefined, title=Undefined, transform=Undefined, width=Undefined, **kwds)¶

CompositeUnitSpec schema wrapper

Mapping(required=[mark])

Attributes:

mark : AnyMark

A string describing the mark type (one of "bar", "circle", "square", "tick", "line", "area", "point", "rule", "geoshape", and "text" ) or a mark definition object.

data : Data

An object describing the data source

description : string

Description of this mark for commenting purpose.

encoding : Encoding

A key-value mapping between encoding channels and definition of fields.

height : float

The height of a visualization.

Default value:

If a view’s autosize type is "fit" or its y-channel has a continuous scale, the height will be the value of config.view.height.
For y-axis with a band or point scale: if rangeStep is a numeric value or unspecified, the height is determined by the range step, paddings, and the cardinality of the field mapped to y-channel. Otherwise, if the rangeStep is null, the height will be the value of config.view.height.
If no field is mapped to y channel, the height will be the value of rangeStep.

Note : For plots with row and column channels, this represents the height of a single view.

See also: The documentation for width and height contains more examples.

name : string

Name of the visualization for later reference.

projection : Projection

An object defining properties of geographic projection, which will be applied to shape path for "geoshape" marks and to latitude and "longitude" channels for other marks.

selection : Mapping(required=[])

A key-value mapping between selection names and definitions.

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

width : float

The width of a visualization.

Default value: This will be determined by the following rules:

If a view’s autosize type is "fit" or its x-channel has a continuous scale, the width will be the value of config.view.width.
For x-axis with a band or point scale: if rangeStep is a numeric value or unspecified, the width is determined by the range step, paddings, and the cardinality of the field mapped to x-channel. Otherwise, if the rangeStep is null, the width will be the value of config.view.width.
If no field is mapped to x channel, the width will be the value of config.scale.textXRangeStep for text mark and the value of rangeStep for other marks.

Note: For plots with row and column channels, this represents the width of a single view.

See also: The documentation for width and height contains more examples.

class altair.CompositeUnitSpecAlias(mark=Undefined, data=Undefined, description=Undefined, encoding=Undefined, height=Undefined, name=Undefined, projection=Undefined, selection=Undefined, title=Undefined, transform=Undefined, width=Undefined, **kwds)¶

CompositeUnitSpecAlias schema wrapper

Mapping(required=[mark])

Attributes:

mark : AnyMark

A string describing the mark type (one of "bar", "circle", "square", "tick", "line", "area", "point", "rule", "geoshape", and "text" ) or a mark definition object.

data : Data

An object describing the data source

description : string

Description of this mark for commenting purpose.

encoding : Encoding

A key-value mapping between encoding channels and definition of fields.

height : float

The height of a visualization.

Default value:

If a view’s autosize type is "fit" or its y-channel has a continuous scale, the height will be the value of config.view.height.
For y-axis with a band or point scale: if rangeStep is a numeric value or unspecified, the height is determined by the range step, paddings, and the cardinality of the field mapped to y-channel. Otherwise, if the rangeStep is null, the height will be the value of config.view.height.
If no field is mapped to y channel, the height will be the value of rangeStep.

Note : For plots with row and column channels, this represents the height of a single view.

See also: The documentation for width and height contains more examples.

name : string

Name of the visualization for later reference.

projection : Projection

An object defining properties of geographic projection, which will be applied to shape path for "geoshape" marks and to latitude and "longitude" channels for other marks.

selection : Mapping(required=[])

A key-value mapping between selection names and definitions.

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

width : float

The width of a visualization.

Default value: This will be determined by the following rules:

If a view’s autosize type is "fit" or its x-channel has a continuous scale, the width will be the value of config.view.width.
For x-axis with a band or point scale: if rangeStep is a numeric value or unspecified, the width is determined by the range step, paddings, and the cardinality of the field mapped to x-channel. Otherwise, if the rangeStep is null, the width will be the value of config.view.width.
If no field is mapped to x channel, the width will be the value of config.scale.textXRangeStep for text mark and the value of rangeStep for other marks.

Note: For plots with row and column channels, this represents the width of a single view.

See also: The documentation for width and height contains more examples.

class altair.ConditionalFieldDef(*args, **kwds)¶

ConditionalFieldDef schema wrapper

anyOf(ConditionalPredicateFieldDef, ConditionalSelectionFieldDef)

class altair.ConditionalMarkPropFieldDef(*args, **kwds)¶

ConditionalMarkPropFieldDef schema wrapper

anyOf(ConditionalPredicateMarkPropFieldDef, ConditionalSelectionMarkPropFieldDef)

class altair.ConditionalPredicateFieldDef(test=Undefined, type=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, **kwds)¶

ConditionalPredicateFieldDef schema wrapper

Mapping(required=[test, type])

Attributes:

test : LogicalOperandPredicate

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

class altair.ConditionalPredicateMarkPropFieldDef(test=Undefined, type=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, legend=Undefined, scale=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, **kwds)¶

ConditionalPredicateMarkPropFieldDef schema wrapper

Mapping(required=[test, type])

Attributes:

test : LogicalOperandPredicate

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

legend : anyOf(Legend, None)

An object defining properties of the legend. If null, the legend for the encoding channel will be removed.

Default value: If undefined, default legend properties are applied.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

<<<<<<< HEAD

sort : anyOf(List(string), SortOrder, EncodingSortField, None)

Sort order for the encoded field. Supported sort values include "ascending", "descending", null (no sorting), or an array specifying the preferred order of values. For fields with discrete domains, sort can also be a sort field definition object. For sort as an array specifying the preferred order of values, the sort order will obey the values in the array, followed by any unspecified values in their original order.

Default value: "ascending"

=======

sort : Sort

Sort order for the encoded field. For continuous fields (quantitative or temporal),: sort can be either "ascending" or "descending". For discrete fields,
sort can be one of the following: * "ascending" or "descending" – for: sorting by the values’ natural order in Javascript. * `A sort field definition

<https://vega.github.io/vega-lite/docs/sort.html#sort-field>`_ for sorting by another field. * An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ). * null indicating no sort. Default value: "ascending" Note: null is not supported for row and column.

>>>>>>> altair-viz/master

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

class altair.ConditionalPredicateTextFieldDef(test=Undefined, type=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, format=Undefined, timeUnit=Undefined, title=Undefined, **kwds)¶

ConditionalPredicateTextFieldDef schema wrapper

Mapping(required=[test, type])

Attributes:

test : LogicalOperandPredicate

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

format : string

The formatting pattern for a text field. If not defined, this will be determined automatically.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

class altair.ConditionalPredicateValueDef(test=Undefined, value=Undefined, **kwds)¶

ConditionalPredicateValueDef schema wrapper

Mapping(required=[test, value])

Attributes:	test : LogicalOperandPredicate value : anyOf(float, string, boolean) A constant value in visual domain (e.g., `"red"` / “#0099ff” for color, values between `0` to `1` for opacity).

class altair.ConditionalSelectionFieldDef(selection=Undefined, type=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, **kwds)¶

ConditionalSelectionFieldDef schema wrapper

Mapping(required=[selection, type])

Attributes:

selection : SelectionOperand

A selection name, or a series of composed selections.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

class altair.ConditionalSelectionMarkPropFieldDef(selection=Undefined, type=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, legend=Undefined, scale=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, **kwds)¶

ConditionalSelectionMarkPropFieldDef schema wrapper

Mapping(required=[selection, type])

Attributes:

selection : SelectionOperand

A selection name, or a series of composed selections.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

legend : anyOf(Legend, None)

An object defining properties of the legend. If null, the legend for the encoding channel will be removed.

Default value: If undefined, default legend properties are applied.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

<<<<<<< HEAD

sort : anyOf(List(string), SortOrder, EncodingSortField, None)

Sort order for the encoded field. Supported sort values include "ascending", "descending", null (no sorting), or an array specifying the preferred order of values. For fields with discrete domains, sort can also be a sort field definition object. For sort as an array specifying the preferred order of values, the sort order will obey the values in the array, followed by any unspecified values in their original order.

Default value: "ascending"

=======

sort : Sort

Sort order for the encoded field. For continuous fields (quantitative or temporal),: sort can be either "ascending" or "descending". For discrete fields,
sort can be one of the following: * "ascending" or "descending" – for: sorting by the values’ natural order in Javascript. * `A sort field definition

<https://vega.github.io/vega-lite/docs/sort.html#sort-field>`_ for sorting by another field. * An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ). * null indicating no sort. Default value: "ascending" Note: null is not supported for row and column.

>>>>>>> altair-viz/master

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

class altair.ConditionalSelectionTextFieldDef(selection=Undefined, type=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, format=Undefined, timeUnit=Undefined, title=Undefined, **kwds)¶

ConditionalSelectionTextFieldDef schema wrapper

Mapping(required=[selection, type])

Attributes:

selection : SelectionOperand

A selection name, or a series of composed selections.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

format : string

The formatting pattern for a text field. If not defined, this will be determined automatically.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

class altair.ConditionalSelectionValueDef(selection=Undefined, value=Undefined, **kwds)¶

ConditionalSelectionValueDef schema wrapper

Mapping(required=[selection, value])

Attributes:	selection : SelectionOperand A selection name, or a series of composed selections. value : anyOf(float, string, boolean) A constant value in visual domain (e.g., `"red"` / “#0099ff” for color, values between `0` to `1` for opacity).

class altair.ConditionalTextFieldDef(*args, **kwds)¶

ConditionalTextFieldDef schema wrapper

anyOf(ConditionalPredicateTextFieldDef, ConditionalSelectionTextFieldDef)

class altair.ConditionalValueDef(*args, **kwds)¶

ConditionalValueDef schema wrapper

anyOf(ConditionalPredicateValueDef, ConditionalSelectionValueDef)

class altair.Config(area=Undefined, autosize=Undefined, axis=Undefined, axisBand=Undefined, axisBottom=Undefined, axisLeft=Undefined, axisRight=Undefined, axisTop=Undefined, axisX=Undefined, axisY=Undefined, background=Undefined, bar=Undefined, circle=Undefined, countTitle=Undefined, datasets=Undefined, fieldTitle=Undefined, geoshape=Undefined, header=Undefined, invalidValues=Undefined, legend=Undefined, line=Undefined, mark=Undefined, numberFormat=Undefined, padding=Undefined, point=Undefined, projection=Undefined, range=Undefined, rect=Undefined, rule=Undefined, scale=Undefined, selection=Undefined, square=Undefined, stack=Undefined, style=Undefined, text=Undefined, tick=Undefined, timeFormat=Undefined, title=Undefined, trail=Undefined, view=Undefined, **kwds)¶

Config schema wrapper

Mapping(required=[])

Attributes:

area : AreaConfig

Area-Specific Config

autosize : anyOf(AutosizeType, AutoSizeParams)

Sets how the visualization size should be determined. If a string, should be one of "pad", "fit" or "none". Object values can additionally specify parameters for content sizing and automatic resizing. "fit" is only supported for single and layered views that don’t use rangeStep.

Default value : pad

axis : AxisConfig

Axis configuration, which determines default properties for all x and y axes. For a full list of axis configuration options, please see the corresponding section of the axis documentation.

axisBand : VgAxisConfig

Specific axis config for axes with “band” scales.

axisBottom : VgAxisConfig

Specific axis config for x-axis along the bottom edge of the chart.

axisLeft : VgAxisConfig

Specific axis config for y-axis along the left edge of the chart.

axisRight : VgAxisConfig

Specific axis config for y-axis along the right edge of the chart.

axisTop : VgAxisConfig

Specific axis config for x-axis along the top edge of the chart.

axisX : VgAxisConfig

X-axis specific config.

axisY : VgAxisConfig

Y-axis specific config.

background : string

CSS color property to use as the background of visualization.

Default value: none (transparent)

bar : BarConfig

Bar-Specific Config

circle : MarkConfig

Circle-Specific Config

countTitle : string

Default axis and legend title for count fields.

Default value: 'Number of Records'.

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

fieldTitle : enum(‘verbal’, ‘functional’, ‘plain’)

Defines how Vega-Lite generates title for fields. There are three possible styles:

"verbal" (Default) - displays function in a verbal style (e.g., “Sum of field”, “Year-month of date”, “field (binned)”).
"function" - displays function using parentheses and capitalized texts (e.g., “SUM(field)”, “YEARMONTH(date)”, “BIN(field)”).
"plain" - displays only the field name without functions (e.g., “field”, “date”, “field”).

geoshape : MarkConfig

Geoshape-Specific Config

header : HeaderConfig

Header configuration, which determines default properties for all header. For a full list of header configuration options, please see the corresponding section of in the header documentation.

invalidValues : enum(‘filter’, None)

Defines how Vega-Lite should handle invalid values ( null and NaN ).

If set to "filter" (default), all data items with null values will be skipped (for line, trail, and area marks) or filtered (for other marks).
If null, all data items are included. In this case, invalid values will be interpreted as zeroes.

legend : LegendConfig

Legend configuration, which determines default properties for all legends. For a full list of legend configuration options, please see the corresponding section of in the legend documentation.

line : LineConfig

Line-Specific Config

mark : MarkConfig

Mark Config

numberFormat : string

D3 Number format for axis labels and text tables. For example “s” for SI units. Use D3’s number format pattern.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

point : MarkConfig

Point-Specific Config

projection : ProjectionConfig

Projection configuration, which determines default properties for all projections. For a full list of projection configuration options, please see the corresponding section of the projection documentation.

range : RangeConfig

An object hash that defines default range arrays or schemes for using with scales. For a full list of scale range configuration options, please see the corresponding section of the scale documentation.

rect : MarkConfig

Rect-Specific Config

rule : MarkConfig

Rule-Specific Config

scale : ScaleConfig

Scale configuration determines default properties for all scales. For a full list of scale configuration options, please see the corresponding section of the scale documentation.

selection : SelectionConfig

An object hash for defining default properties for each type of selections.

square : MarkConfig

Square-Specific Config

stack : StackOffset

Default stack offset for stackable mark.

style : StyleConfigIndex

An object hash that defines key-value mappings to determine default properties for marks with a given style. The keys represent styles names; the values have to be valid mark configuration objects.

text : TextConfig

Text-Specific Config

tick : TickConfig

Tick-Specific Config

timeFormat : string

Default datetime format for axis and legend labels. The format can be set directly on each axis and legend. Use D3’s time format pattern.

Default value: '' (The format will be automatically determined).

title : VgTitleConfig

Title configuration, which determines default properties for all titles. For a full list of title configuration options, please see the corresponding section of the title documentation.

trail : LineConfig

Trail-Specific Config

view : ViewConfig

Default properties for single view plots.

class altair.CsvDataFormat(parse=Undefined, type=Undefined, **kwds)¶

CsvDataFormat schema wrapper

Mapping(required=[])

Attributes:

parse : anyOf(enum(‘auto’), Parse, None)

If set to "auto" (the default), perform automatic type inference to determine the desired data types. If set to null, disable type inference based on the spec and only use type inference based on the data. Alternatively, a parsing directive object can be provided for explicit data types. Each property of the object corresponds to a field name, and the value to the desired data type (one of "number", "boolean", "date", or null (do not parse the field)). For example, "parse": {"modified_on": "date"} parses the modified_on field in each input record a Date value.

For "date", we parse data based using Javascript’s Date.parse(). For Specific date formats can be provided (e.g., {foo: 'date:"%m%d%Y"'} ), using the d3-time-format syntax. UTC date format parsing is supported similarly (e.g., {foo: 'utc:"%m%d%Y"'} ). See more about UTC time

type : enum(‘csv’, ‘tsv’)

Type of input data: "json", "csv", "tsv", "dsv". The default format type is determined by the extension of the file URL. If no extension is detected, "json" will be used by default.

class altair.Cursor(*args)¶

Cursor schema wrapper

enum(‘auto’, ‘default’, ‘none’, ‘context-menu’, ‘help’, ‘pointer’, ‘progress’, ‘wait’, ‘cell’, ‘crosshair’, ‘text’, ‘vertical-text’, ‘alias’, ‘copy’, ‘move’, ‘no-drop’, ‘not-allowed’, ‘e-resize’, ‘n-resize’, ‘ne-resize’, ‘nw-resize’, ‘s-resize’, ‘se-resize’, ‘sw-resize’, ‘w-resize’, ‘ew-resize’, ‘ns-resize’, ‘nesw-resize’, ‘nwse-resize’, ‘col-resize’, ‘row-resize’, ‘all-scroll’, ‘zoom-in’, ‘zoom-out’, ‘grab’, ‘grabbing’)

class altair.Data(*args, **kwds)¶

Data schema wrapper

anyOf(UrlData, InlineData, NamedData)

class altair.DataFormat(*args, **kwds)¶

DataFormat schema wrapper

anyOf(CsvDataFormat, DsvDataFormat, JsonDataFormat, TopoDataFormat)

class altair.Datasets(**kwds)¶

Datasets schema wrapper

Mapping(required=[])

class altair.DateTime(date=Undefined, day=Undefined, hours=Undefined, milliseconds=Undefined, minutes=Undefined, month=Undefined, quarter=Undefined, seconds=Undefined, utc=Undefined, year=Undefined, **kwds)¶

DateTime schema wrapper

Mapping(required=[]) Object for defining datetime in Vega-Lite Filter. If both month and quarter are provided, month has higher precedence. day cannot be combined with other date. We accept string for month and day names.

Attributes:

date : float: Integer value representing the date from 1-31.
day : anyOf(Day, string): Value representing the day of a week. This can be one of: (1) integer value – 1 represents Monday; (2) case-insensitive day name (e.g., "Monday" ); (3) case-insensitive, 3-character short day name (e.g., "Mon" ).
Warning: A DateTime definition object with day ** should not be combined with year, quarter, month, or date.
hours : float: Integer value representing the hour of a day from 0-23.
milliseconds : float: Integer value representing the millisecond segment of time.
minutes : float: Integer value representing the minute segment of time from 0-59.
month : anyOf(Month, string): One of: (1) integer value representing the month from 1 - 12. 1 represents January; (2) case-insensitive month name (e.g., "January" ); (3) case-insensitive, 3-character short month name (e.g., "Jan" ).
quarter : float: Integer value representing the quarter of the year (from 1-4).
seconds : float: Integer value representing the second segment (0-59) of a time value
utc : boolean: A boolean flag indicating if date time is in utc time. If false, the date time is in local time
year : float: Integer value representing the year.

class altair.Day(*args)¶

Day schema wrapper

float

class altair.Detail(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

Detail schema wrapper

Mapping(required=[shorthand]) Definition object for a data field, its type and transformation of an encoding channel.

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.DictInlineDataset(**kwds)¶

DictInlineDataset schema wrapper

Mapping(required=[])

class altair.Dir(*args)¶

Dir schema wrapper

enum(‘ltr’, ‘rtl’)

class altair.DsvDataFormat(delimiter=Undefined, parse=Undefined, type=Undefined, **kwds)¶

DsvDataFormat schema wrapper

Mapping(required=[delimiter])

Attributes:

delimiter : string

The delimiter between records. The delimiter must be a single character (i.e., a single 16-bit code unit); so, ASCII delimiters are fine, but emoji delimiters are not.

parse : anyOf(enum(‘auto’), Parse, None)

If set to "auto" (the default), perform automatic type inference to determine the desired data types. If set to null, disable type inference based on the spec and only use type inference based on the data. Alternatively, a parsing directive object can be provided for explicit data types. Each property of the object corresponds to a field name, and the value to the desired data type (one of "number", "boolean", "date", or null (do not parse the field)). For example, "parse": {"modified_on": "date"} parses the modified_on field in each input record a Date value.

For "date", we parse data based using Javascript’s Date.parse(). For Specific date formats can be provided (e.g., {foo: 'date:"%m%d%Y"'} ), using the d3-time-format syntax. UTC date format parsing is supported similarly (e.g., {foo: 'utc:"%m%d%Y"'} ). See more about UTC time

type : enum(‘dsv’)

Type of input data: "json", "csv", "tsv", "dsv". The default format type is determined by the extension of the file URL. If no extension is detected, "json" will be used by default.

class altair.Encoding(color=Undefined, detail=Undefined, fill=Undefined, href=Undefined, key=Undefined, latitude=Undefined, latitude2=Undefined, longitude=Undefined, longitude2=Undefined, opacity=Undefined, order=Undefined, shape=Undefined, size=Undefined, stroke=Undefined, text=Undefined, tooltip=Undefined, x=Undefined, x2=Undefined, y=Undefined, y2=Undefined, **kwds)¶

Encoding schema wrapper

Mapping(required=[])

Attributes:

color : anyOf(MarkPropFieldDefWithCondition, MarkPropValueDefWithCondition)

Color of the marks – either fill or stroke color based on the filled property of mark definition. By default, color represents fill color for "area", "bar", "tick", "text", "trail", "circle", and "square" / stroke color for "line" and "point".

Default value: If undefined, the default color depends on mark config ‘s color property.

Note: 1) For fine-grained control over both fill and stroke colors of the marks, please use the fill and stroke channels. If either fill or stroke channel is specified, color channel will be ignored. 2) See the scale documentation for more information about customizing color scheme.

detail : anyOf(FieldDef, List(FieldDef))

Additional levels of detail for grouping data in aggregate views and in line, trail, and area marks without mapping data to a specific visual channel.

fill : anyOf(MarkPropFieldDefWithCondition, MarkPropValueDefWithCondition)

Fill color of the marks. Default value: If undefined, the default color depends on mark config ‘s color property.

Note: When using fill channel, color channel will be ignored. To customize both fill and stroke, please use fill and stroke channels (not fill and color ).

href : anyOf(FieldDefWithCondition, ValueDefWithCondition)

A URL to load upon mouse click.

key : FieldDef

A data field to use as a unique key for data binding. When a visualization’s data is updated, the key value will be used to match data elements to existing mark instances. Use a key channel to enable object constancy for transitions over dynamic data.

latitude : FieldDef

Latitude position of geographically projected marks.

latitude2 : FieldDef

Latitude-2 position for geographically projected ranged "area", "bar", "rect", and "rule".

longitude : FieldDef

Longitude position of geographically projected marks.

longitude2 : FieldDef

Longitude-2 position for geographically projected ranged "area", "bar", "rect", and "rule".

opacity : anyOf(MarkPropFieldDefWithCondition, MarkPropValueDefWithCondition)

Opacity of the marks – either can be a value or a range.

Default value: If undefined, the default opacity depends on mark config ‘s opacity property.

order : anyOf(OrderFieldDef, List(OrderFieldDef), ValueDef)

Order of the marks.

For stacked marks, this order channel encodes stack order.
For line and trail marks, this order channel encodes order of data points in the lines. This can be useful for creating a connected scatterplot. Setting order to {"value": null} makes the line marks use the original order in the data sources.
Otherwise, this order channel encodes layer order of the marks.

Note : In aggregate plots, order field should be aggregate d to avoid creating additional aggregation grouping.

shape : anyOf(MarkPropFieldDefWithCondition, MarkPropValueDefWithCondition)

For point marks the supported values are "circle" (default), "square", "cross", "diamond", "triangle-up", or "triangle-down", or else a custom SVG path string. For geoshape marks it should be a field definition of the geojson data

Default value: If undefined, the default shape depends on mark config ‘s shape property.

size : anyOf(MarkPropFieldDefWithCondition, MarkPropValueDefWithCondition)

Size of the mark.

For "point", "square" and "circle", – the symbol size, or pixel area of the mark.
For "bar" and "tick" – the bar and tick’s size.
For "text" – the text’s font size.
Size is unsupported for "line", "area", and "rect". (Use "trail" instead of line with varying size)

stroke : anyOf(MarkPropFieldDefWithCondition, MarkPropValueDefWithCondition)

Stroke color of the marks. Default value: If undefined, the default color depends on mark config ‘s color property.

Note: When using stroke channel, color channel will be ignored. To customize both stroke and fill, please use stroke and fill channels (not stroke and color ).

text : anyOf(TextFieldDefWithCondition, TextValueDefWithCondition)

Text of the text mark.

tooltip : anyOf(TextFieldDefWithCondition, TextValueDefWithCondition, List(TextFieldDef))

The tooltip text to show upon mouse hover.

x : anyOf(PositionFieldDef, ValueDef)

X coordinates of the marks, or width of horizontal "bar" and "area".

x2 : anyOf(FieldDef, ValueDef)

X2 coordinates for ranged "area", "bar", "rect", and "rule".

y : anyOf(PositionFieldDef, ValueDef)

Y coordinates of the marks, or height of vertical "bar" and "area".

y2 : anyOf(FieldDef, ValueDef)

Y2 coordinates for ranged "area", "bar", "rect", and "rule".

class altair.EncodingSortField(op=Undefined, field=Undefined, order=Undefined, **kwds)¶

EncodingSortField schema wrapper

Mapping(required=[op]) A sort definition for sorting a discrete scale in an encoding field definition.

Attributes:

op : AggregateOp

An aggregate operation to perform on the field prior to sorting (e.g., "count", "mean" and "median" ). This property is required in cases where the sort field and the data reference field do not match. The input data objects will be aggregated, grouped by the encoded data field.

For a full list of operations, please see the documentation for aggregate.

field : anyOf(string, RepeatRef)

The data field to sort by.

Default value: If unspecified, defaults to the field specified in the outer data reference.

order : SortOrder

The sort order. One of "ascending" (default), "descending", or null (no not sort).

class altair.EncodingWithFacet(color=Undefined, column=Undefined, detail=Undefined, fill=Undefined, href=Undefined, key=Undefined, latitude=Undefined, latitude2=Undefined, longitude=Undefined, longitude2=Undefined, opacity=Undefined, order=Undefined, row=Undefined, shape=Undefined, size=Undefined, stroke=Undefined, text=Undefined, tooltip=Undefined, x=Undefined, x2=Undefined, y=Undefined, y2=Undefined, **kwds)¶

EncodingWithFacet schema wrapper

Mapping(required=[])

Attributes:

color : anyOf(MarkPropFieldDefWithCondition, MarkPropValueDefWithCondition)

Color of the marks – either fill or stroke color based on the filled property of mark definition. By default, color represents fill color for "area", "bar", "tick", "text", "trail", "circle", and "square" / stroke color for "line" and "point".

Default value: If undefined, the default color depends on mark config ‘s color property.

Note: 1) For fine-grained control over both fill and stroke colors of the marks, please use the fill and stroke channels. If either fill or stroke channel is specified, color channel will be ignored. 2) See the scale documentation for more information about customizing color scheme.

column : FacetFieldDef

Horizontal facets for trellis plots.

detail : anyOf(FieldDef, List(FieldDef))

Additional levels of detail for grouping data in aggregate views and in line, trail, and area marks without mapping data to a specific visual channel.

fill : anyOf(MarkPropFieldDefWithCondition, MarkPropValueDefWithCondition)

Fill color of the marks. Default value: If undefined, the default color depends on mark config ‘s color property.

Note: When using fill channel, color channel will be ignored. To customize both fill and stroke, please use fill and stroke channels (not fill and color ).

href : anyOf(FieldDefWithCondition, ValueDefWithCondition)

A URL to load upon mouse click.

key : FieldDef

A data field to use as a unique key for data binding. When a visualization’s data is updated, the key value will be used to match data elements to existing mark instances. Use a key channel to enable object constancy for transitions over dynamic data.

latitude : FieldDef

Latitude position of geographically projected marks.

latitude2 : FieldDef

Latitude-2 position for geographically projected ranged "area", "bar", "rect", and "rule".

longitude : FieldDef

Longitude position of geographically projected marks.

longitude2 : FieldDef

Longitude-2 position for geographically projected ranged "area", "bar", "rect", and "rule".

opacity : anyOf(MarkPropFieldDefWithCondition, MarkPropValueDefWithCondition)

Opacity of the marks – either can be a value or a range.

Default value: If undefined, the default opacity depends on mark config ‘s opacity property.

order : anyOf(OrderFieldDef, List(OrderFieldDef), ValueDef)

Order of the marks.

For stacked marks, this order channel encodes stack order.
For line and trail marks, this order channel encodes order of data points in the lines. This can be useful for creating a connected scatterplot. Setting order to {"value": null} makes the line marks use the original order in the data sources.
Otherwise, this order channel encodes layer order of the marks.

Note : In aggregate plots, order field should be aggregate d to avoid creating additional aggregation grouping.

row : FacetFieldDef

Vertical facets for trellis plots.

shape : anyOf(MarkPropFieldDefWithCondition, MarkPropValueDefWithCondition)

For point marks the supported values are "circle" (default), "square", "cross", "diamond", "triangle-up", or "triangle-down", or else a custom SVG path string. For geoshape marks it should be a field definition of the geojson data

Default value: If undefined, the default shape depends on mark config ‘s shape property.

size : anyOf(MarkPropFieldDefWithCondition, MarkPropValueDefWithCondition)

Size of the mark.

For "point", "square" and "circle", – the symbol size, or pixel area of the mark.
For "bar" and "tick" – the bar and tick’s size.
For "text" – the text’s font size.
Size is unsupported for "line", "area", and "rect". (Use "trail" instead of line with varying size)

stroke : anyOf(MarkPropFieldDefWithCondition, MarkPropValueDefWithCondition)

Stroke color of the marks. Default value: If undefined, the default color depends on mark config ‘s color property.

Note: When using stroke channel, color channel will be ignored. To customize both stroke and fill, please use stroke and fill channels (not stroke and color ).

text : anyOf(TextFieldDefWithCondition, TextValueDefWithCondition)

Text of the text mark.

tooltip : anyOf(TextFieldDefWithCondition, TextValueDefWithCondition, List(TextFieldDef))

The tooltip text to show upon mouse hover.

x : anyOf(PositionFieldDef, ValueDef)

X coordinates of the marks, or width of horizontal "bar" and "area".

x2 : anyOf(FieldDef, ValueDef)

X2 coordinates for ranged "area", "bar", "rect", and "rule".

y : anyOf(PositionFieldDef, ValueDef)

Y coordinates of the marks, or height of vertical "bar" and "area".

y2 : anyOf(FieldDef, ValueDef)

Y2 coordinates for ranged "area", "bar", "rect", and "rule".

class altair.FacetFieldDef(type=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, header=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, **kwds)¶

FacetFieldDef schema wrapper

Mapping(required=[type])

Attributes:

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

header : Header

An object defining properties of a facet’s header.

<<<<<<< HEAD

sort : SortOrder: Sort order for a facet field. This can be "ascending", "descending".

=======

sort : Sort

Sort order for the encoded field. For continuous fields (quantitative or temporal),: sort can be either "ascending" or "descending". For discrete fields,
sort can be one of the following: * "ascending" or "descending" – for: sorting by the values’ natural order in Javascript. * `A sort field definition

<https://vega.github.io/vega-lite/docs/sort.html#sort-field>`_ for sorting by another field. * An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ). * null indicating no sort. Default value: "ascending" Note: null is not supported for row and column.

>>>>>>> altair-viz/master

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

class altair.FacetMapping(column=Undefined, row=Undefined, **kwds)¶

FacetMapping schema wrapper

Mapping(required=[])

Attributes:	column : FacetFieldDef Horizontal facets for trellis plots. row : FacetFieldDef Vertical facets for trellis plots.

to_dict(*args, **kwargs)¶

Return a dictionary representation of the object

Parameters:	validate : boolean or string If True (default), then validate the output dictionary against the schema. If “deep” then recursively validate all objects in the spec. This takes much more time, but it results in friendlier tracebacks for large objects. ignore : list A list of keys to ignore. This will not passed to child to_dict function calls. context : dict (optional) A context dictionary that will be passed to all child to_dict function calls
Returns:	dct : dictionary The dictionary representation of this object
Raises:	jsonschema.ValidationError : if validate=True and the dict does not conform to the schema

class altair.FacetSpec(facet=Undefined, spec=Undefined, align=Undefined, bounds=Undefined, center=Undefined, data=Undefined, description=Undefined, name=Undefined, resolve=Undefined, spacing=Undefined, title=Undefined, transform=Undefined, **kwds)¶

FacetSpec schema wrapper

Mapping(required=[facet, spec])

Attributes:

facet : FacetMapping

An object that describes mappings between row and column channels and their field definitions.

spec : anyOf(LayerSpec, CompositeUnitSpec)

A specification of the view that gets faceted.

align : anyOf(VgLayoutAlign, RowColVgLayoutAlign)

The alignment to apply to grid rows and columns. The supported string values are "all", "each", and "none". * For "none", a flow layout will be used, in which adjacent subviews are simply placed one after the other. * For "each", subviews will be aligned into a clean grid structure, but each row or column may be of variable size. * For "all", subviews will be aligned and each row or column will be sized identically based on the maximum observed size. String values for this property will be applied to both grid rows and columns. Alternatively, an object value of the form {"row": string, "column": string} can

be used to supply different alignments for rows and columns. Default value:

"all".

bounds : enum(‘full’, ‘flush’)

The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"

center : anyOf(boolean, RowColboolean)

Boolean flag indicating if subviews should be centered relative to their respective rows or columns. An object value of the form {"row": boolean, "column": boolean} can be used to supply different centering values for rows and columns. Default value: false

data : Data

An object describing the data source

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

resolve : Resolve

Scale, axis, and legend resolutions for facets.

spacing : anyOf(float, RowColnumber)

The spacing in pixels between sub-views of the composition operator. An object of the form {"row": number, "column": number} can be used to set different spacing values for rows and columns. Default value : 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

class altair.FacetedCompositeUnitSpecAlias(mark=Undefined, data=Undefined, description=Undefined, encoding=Undefined, height=Undefined, name=Undefined, projection=Undefined, selection=Undefined, title=Undefined, transform=Undefined, width=Undefined, **kwds)¶

FacetedCompositeUnitSpecAlias schema wrapper

Mapping(required=[mark])

Attributes:

mark : AnyMark

A string describing the mark type (one of "bar", "circle", "square", "tick", "line", "area", "point", "rule", "geoshape", and "text" ) or a mark definition object.

data : Data

An object describing the data source

description : string

Description of this mark for commenting purpose.

encoding : EncodingWithFacet

A key-value mapping between encoding channels and definition of fields.

height : float

The height of a visualization.

Default value:

If a view’s autosize type is "fit" or its y-channel has a continuous scale, the height will be the value of config.view.height.
For y-axis with a band or point scale: if rangeStep is a numeric value or unspecified, the height is determined by the range step, paddings, and the cardinality of the field mapped to y-channel. Otherwise, if the rangeStep is null, the height will be the value of config.view.height.
If no field is mapped to y channel, the height will be the value of rangeStep.

Note : For plots with row and column channels, this represents the height of a single view.

See also: The documentation for width and height contains more examples.

name : string

Name of the visualization for later reference.

projection : Projection

An object defining properties of geographic projection, which will be applied to shape path for "geoshape" marks and to latitude and "longitude" channels for other marks.

selection : Mapping(required=[])

A key-value mapping between selection names and definitions.

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

width : float

The width of a visualization.

Default value: This will be determined by the following rules:

If a view’s autosize type is "fit" or its x-channel has a continuous scale, the width will be the value of config.view.width.
For x-axis with a band or point scale: if rangeStep is a numeric value or unspecified, the width is determined by the range step, paddings, and the cardinality of the field mapped to x-channel. Otherwise, if the rangeStep is null, the width will be the value of config.view.width.
If no field is mapped to x channel, the width will be the value of config.scale.textXRangeStep for text mark and the value of rangeStep for other marks.

Note: For plots with row and column channels, this represents the width of a single view.

See also: The documentation for width and height contains more examples.

class altair.FieldDef(type=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, **kwds)¶

FieldDef schema wrapper

Mapping(required=[type]) Definition object for a data field, its type and transformation of an encoding channel.

Attributes:

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

class altair.FieldDefWithCondition(type=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, **kwds)¶

FieldDefWithCondition schema wrapper

Mapping(required=[type]) A FieldDef with Condition

Attributes:

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

class altair.FieldEqualPredicate(equal=Undefined, field=Undefined, timeUnit=Undefined, **kwds)¶

FieldEqualPredicate schema wrapper

Mapping(required=[equal, field])

Attributes:	equal : anyOf(string, float, boolean, DateTime) The value that the field should be equal to. field : string Field to be filtered. timeUnit : TimeUnit Time unit for the field to be filtered.

class altair.FieldGTEPredicate(field=Undefined, gte=Undefined, timeUnit=Undefined, **kwds)¶

FieldGTEPredicate schema wrapper

Mapping(required=[field, gte])

Attributes:	field : string Field to be filtered. gte : anyOf(string, float, DateTime) The value that the field should be greater than or equals to. timeUnit : TimeUnit Time unit for the field to be filtered.

class altair.FieldGTPredicate(field=Undefined, gt=Undefined, timeUnit=Undefined, **kwds)¶

FieldGTPredicate schema wrapper

Mapping(required=[field, gt])

Attributes:	field : string Field to be filtered. gt : anyOf(string, float, DateTime) The value that the field should be greater than. timeUnit : TimeUnit Time unit for the field to be filtered.

class altair.FieldLTEPredicate(field=Undefined, lte=Undefined, timeUnit=Undefined, **kwds)¶

FieldLTEPredicate schema wrapper

Mapping(required=[field, lte])

Attributes:	field : string Field to be filtered. lte : anyOf(string, float, DateTime) The value that the field should be less than or equals to. timeUnit : TimeUnit Time unit for the field to be filtered.

class altair.FieldLTPredicate(field=Undefined, lt=Undefined, timeUnit=Undefined, **kwds)¶

FieldLTPredicate schema wrapper

Mapping(required=[field, lt])

Attributes:	field : string Field to be filtered. lt : anyOf(string, float, DateTime) The value that the field should be less than. timeUnit : TimeUnit Time unit for the field to be filtered.

class altair.FieldOneOfPredicate(field=Undefined, oneOf=Undefined, timeUnit=Undefined, **kwds)¶

FieldOneOfPredicate schema wrapper

Mapping(required=[field, oneOf])

Attributes:	field : string Field to be filtered. oneOf : anyOf(List(string), List(float), List(boolean), List(DateTime)) A set of values that the `field` ‘s value should be a member of, for a data item included in the filtered data. timeUnit : TimeUnit Time unit for the field to be filtered.

class altair.FieldRangePredicate(field=Undefined, range=Undefined, timeUnit=Undefined, **kwds)¶

FieldRangePredicate schema wrapper

Mapping(required=[field, range])

Attributes:	field : string Field to be filtered. range : List(anyOf(float, DateTime, None)) An array of inclusive minimum and maximum values for a field value of a data item to be included in the filtered data. timeUnit : TimeUnit Time unit for the field to be filtered.

class altair.Fill(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, legend=Undefined, scale=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Fill schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

legend : anyOf(Legend, None)

An object defining properties of the legend. If null, the legend for the encoding channel will be removed.

Default value: If undefined, default legend properties are applied.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.FillValue(value, condition=Undefined, **kwds)¶

FillValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalMarkPropFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.FilterTransform(filter=Undefined, **kwds)¶

FilterTransform schema wrapper

Mapping(required=[filter])

Attributes:	filter : LogicalOperandPredicate The `filter` property must be one of the predicate definitions: 1) an expression string, where `datum` can be used to refer to the current data object 2) one of the field predicates: equal, lt, lte, gt, gte, range, or oneOf. 3) a selection predicate a logical operand that combines (1), (2), or (3).

class altair.FontStyle(*args)¶

FontStyle schema wrapper

enum(‘normal’, ‘italic’)

class altair.FontWeight(*args, **kwds)¶

FontWeight schema wrapper

anyOf(FontWeightString, FontWeightNumber)

class altair.FontWeightNumber(*args)¶

FontWeightNumber schema wrapper

float

class altair.FontWeightString(*args)¶

FontWeightString schema wrapper

enum(‘normal’, ‘bold’)

class altair.GeoType(*args)¶

GeoType schema wrapper

enum(‘latitude’, ‘longitude’, ‘geojson’)

class altair.HConcatChart(data=Undefined, hconcat=(), **kwargs)

A chart with horizontally-concatenated facets: Mapping(required=[hconcat])

Attributes:

hconcat : List(Spec)

A list of views that should be concatenated and put into a row.

autosize : anyOf(AutosizeType, AutoSizeParams)

Sets how the visualization size should be determined. If a string, should be one of "pad", "fit" or "none". Object values can additionally specify parameters for content sizing and automatic resizing. "fit" is only supported for single and layered views that don’t use rangeStep.

Default value : pad

background : string

<<<<<<< HEAD

CSS color property to use as the background of visualization.

Default value: none (transparent)

=======

CSS color property to use as the background of visualization. Default value: none (transparent)

bounds : enum(‘full’, ‘flush’): The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"
center : boolean: Boolean flag indicating if subviews should be centered relative to their respective rows or columns. Default value: false

>>>>>>> altair-viz/master

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

data : Data

An object describing the data source

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

resolve : Resolve

Scale, axis, and legend resolutions for horizontally concatenated charts.

spacing : float

The spacing in pixels between sub-views of the concat operator. Default value :: 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

$schema : string

URL to JSON schema for a Vega-Lite specification. Unless you have a reason to change this, use https://vega.github.io/schema/vega-lite/v2.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

class altair.HConcatSpec(hconcat=Undefined, bounds=Undefined, center=Undefined, data=Undefined, description=Undefined, name=Undefined, resolve=Undefined, spacing=Undefined, title=Undefined, transform=Undefined, **kwds)¶

HConcatSpec schema wrapper

Mapping(required=[hconcat])

Attributes:

hconcat : List(Spec)

A list of views that should be concatenated and put into a row.

bounds : enum(‘full’, ‘flush’)

The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"

center : boolean

Boolean flag indicating if subviews should be centered relative to their respective rows or columns. Default value: false

data : Data

An object describing the data source

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

resolve : Resolve

Scale, axis, and legend resolutions for horizontally concatenated charts.

spacing : float

The spacing in pixels between sub-views of the concat operator. Default value :: 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

class altair.Header(format=Undefined, labelAngle=Undefined, labelColor=Undefined, labelFont=Undefined, labelFontSize=Undefined, labelLimit=Undefined, title=Undefined, titleAnchor=Undefined, titleAngle=Undefined, titleBaseline=Undefined, titleColor=Undefined, titleFont=Undefined, titleFontSize=Undefined, titleFontWeight=Undefined, titleLimit=Undefined, **kwds)¶

Header schema wrapper

Mapping(required=[]) Headers of row / column channels for faceted plots.

Attributes:

format : string

The formatting pattern for labels. This is D3’s number format pattern for quantitative fields and D3’s time format pattern for time field.

See the format documentation for more information.

Default value: derived from numberFormat config for quantitative fields and from timeFormat config for temporal fields.

labelAngle : float

The rotation angle of the header labels. Default value: 0.

labelColor : string

The color of the header label, can be in hex color code or regular color name.

labelFont : string

The font of the header label.

labelFontSize : float

The font size of the header label, in pixels.

labelLimit : float

The maximum length of the header label in pixels. The text value will be automatically truncated if the rendered size exceeds the limit. Default value: 0, indicating no limit

title : anyOf(string, None)

A title for the field. If null, the title will be removed. Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name. Notes : 1) You can customize the default field title

format by providing the [ fieldTitle property in the `config

<https://vega.github.io/vega-lite/docs/config.html>`_ or ` fieldTitle function via the compile function’s options <https://vega.github.io/vega-lite/docs/compile.html#field-title>`_. 2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

titleAnchor : string

The anchor position for placing the title. One of "start", "middle", or "end". For example, with an orientation of top these anchor positions map to a left-, center-, or right-aligned title. Default value: "middle" for `single

<https://vega.github.io/vega-lite/docs/spec.html>`_ and `layered

<https://vega.github.io/vega-lite/docs/layer.html>`_ views. "start" for other composite views. Note: For now, anchor is only customizable only for single and layered views. For other composite views, anchor is always "start".

titleAngle : float

The rotation angle of the header title. Default value: 0.

titleBaseline : TextBaseline

Vertical text baseline for the header title. One of "top", "bottom", "middle". Default value: "middle"

titleColor : string

Color of the header title, can be in hex color code or regular color name.

titleFont : string

Font of the header title. (e.g., "Helvetica Neue" ).

titleFontSize : float

Font size of the header title.

titleFontWeight : FontWeight

Font weight of the header title. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

titleLimit : float

The maximum length of the header title in pixels. The text value will be automatically truncated if the rendered size exceeds the limit. Default value: 0, indicating no limit

class altair.HeaderConfig(labelAngle=Undefined, labelColor=Undefined, labelFont=Undefined, labelFontSize=Undefined, labelLimit=Undefined, titleAnchor=Undefined, titleAngle=Undefined, titleBaseline=Undefined, titleColor=Undefined, titleFont=Undefined, titleFontSize=Undefined, titleFontWeight=Undefined, titleLimit=Undefined, **kwds)¶

HeaderConfig schema wrapper

Mapping(required=[])

Attributes:

labelAngle : float

The rotation angle of the header labels. Default value: 0.

labelColor : string

The color of the header label, can be in hex color code or regular color name.

labelFont : string

The font of the header label.

labelFontSize : float

The font size of the header label, in pixels.

labelLimit : float

The maximum length of the header label in pixels. The text value will be automatically truncated if the rendered size exceeds the limit. Default value: 0, indicating no limit

titleAnchor : string

The anchor position for placing the title. One of "start", "middle", or "end". For example, with an orientation of top these anchor positions map to a left-, center-, or right-aligned title. Default value: "middle" for `single

<https://vega.github.io/vega-lite/docs/spec.html>`_ and `layered

<https://vega.github.io/vega-lite/docs/layer.html>`_ views. "start" for other composite views. Note: For now, anchor is only customizable only for single and layered views. For other composite views, anchor is always "start".

titleAngle : float

The rotation angle of the header title. Default value: 0.

titleBaseline : TextBaseline

Vertical text baseline for the header title. One of "top", "bottom", "middle". Default value: "middle"

titleColor : string

Color of the header title, can be in hex color code or regular color name.

titleFont : string

Font of the header title. (e.g., "Helvetica Neue" ).

titleFontSize : float

Font size of the header title.

titleFontWeight : FontWeight

Font weight of the header title. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

titleLimit : float

The maximum length of the header title in pixels. The text value will be automatically truncated if the rendered size exceeds the limit. Default value: 0, indicating no limit

class altair.HorizontalAlign(*args)¶

HorizontalAlign schema wrapper

enum(‘left’, ‘right’, ‘center’)

class altair.Href(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

Href schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.HrefValue(value, condition=Undefined, **kwds)

HrefValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.InlineData(values=Undefined, format=Undefined, name=Undefined, **kwds)¶

InlineData schema wrapper

Mapping(required=[values])

Attributes:

values : InlineDataset: The full data set, included inline. This can be an array of objects or primitive values, an object, or a string. Arrays of primitive values are ingested as objects with a data property. Strings are parsed according to the specified format type.
format : DataFormat: An object that specifies the format for parsing the data.
name : string: Provide a placeholder name and bind data at runtime.

class altair.InlineDataset(*args, **kwds)¶

InlineDataset schema wrapper

anyOf(List(float), List(string), List(boolean), List(Mapping(required=[])), string, Mapping(required=[]))

class altair.Interpolate(*args)¶

Interpolate schema wrapper

enum(‘linear’, ‘linear-closed’, ‘step’, ‘step-before’, ‘step-after’, ‘basis’, ‘basis-open’, ‘basis-closed’, ‘cardinal’, ‘cardinal-open’, ‘cardinal-closed’, ‘bundle’, ‘monotone’)

class altair.IntervalSelection(type=Undefined, bind=Undefined, empty=Undefined, encodings=Undefined, fields=Undefined, mark=Undefined, on=Undefined, resolve=Undefined, translate=Undefined, zoom=Undefined, **kwds)¶

IntervalSelection schema wrapper

Mapping(required=[type])

Attributes:

type : enum(‘interval’)

bind : enum(‘scales’)

Establishes a two-way binding between the interval selection and the scales used within the same view. This allows a user to interactively pan and zoom the view.

empty : enum(‘all’, ‘none’)

By default, all data values are considered to lie within an empty selection. When set to none, empty selections contain no data values.

encodings : List(SingleDefChannel)

An array of encoding channels. The corresponding data field values must match for a data tuple to fall within the selection.

fields : List(string)

An array of field names whose values must match for a data tuple to fall within the selection.

mark : BrushConfig

An interval selection also adds a rectangle mark to depict the extents of the interval. The mark property can be used to customize the appearance of the mark.

on : VgEventStream

A Vega event stream (object or selector) that triggers the selection. For interval selections, the event stream must specify a start and end.

resolve : SelectionResolution

With layered and multi-view displays, a strategy that determines how selections’ data queries are resolved when applied in a filter transform, conditional encoding rule, or scale domain.

translate : anyOf(string, boolean)

When truthy, allows a user to interactively move an interval selection back-and-forth. Can be true, false (to disable panning), or a Vega event stream definition which must include a start and end event to trigger continuous panning.

Default value: true, which corresponds to [mousedown, window:mouseup] > window:mousemove! which corresponds to clicks and dragging within an interval selection to reposition it.

zoom : anyOf(string, boolean)

When truthy, allows a user to interactively resize an interval selection. Can be true, false (to disable zooming), or a Vega event stream definition. Currently, only wheel events are supported.

Default value: true, which corresponds to wheel!.

class altair.IntervalSelectionConfig(bind=Undefined, empty=Undefined, encodings=Undefined, fields=Undefined, mark=Undefined, on=Undefined, resolve=Undefined, translate=Undefined, zoom=Undefined, **kwds)¶

IntervalSelectionConfig schema wrapper

Mapping(required=[])

Attributes:

bind : enum(‘scales’)

Establishes a two-way binding between the interval selection and the scales used within the same view. This allows a user to interactively pan and zoom the view.

empty : enum(‘all’, ‘none’)

By default, all data values are considered to lie within an empty selection. When set to none, empty selections contain no data values.

encodings : List(SingleDefChannel)

An array of encoding channels. The corresponding data field values must match for a data tuple to fall within the selection.

fields : List(string)

An array of field names whose values must match for a data tuple to fall within the selection.

mark : BrushConfig

An interval selection also adds a rectangle mark to depict the extents of the interval. The mark property can be used to customize the appearance of the mark.

on : VgEventStream

A Vega event stream (object or selector) that triggers the selection. For interval selections, the event stream must specify a start and end.

resolve : SelectionResolution

With layered and multi-view displays, a strategy that determines how selections’ data queries are resolved when applied in a filter transform, conditional encoding rule, or scale domain.

translate : anyOf(string, boolean)

When truthy, allows a user to interactively move an interval selection back-and-forth. Can be true, false (to disable panning), or a Vega event stream definition which must include a start and end event to trigger continuous panning.

Default value: true, which corresponds to [mousedown, window:mouseup] > window:mousemove! which corresponds to clicks and dragging within an interval selection to reposition it.

zoom : anyOf(string, boolean)

When truthy, allows a user to interactively resize an interval selection. Can be true, false (to disable zooming), or a Vega event stream definition. Currently, only wheel events are supported.

Default value: true, which corresponds to wheel!.

class altair.JsonDataFormat(parse=Undefined, property=Undefined, type=Undefined, **kwds)¶

JsonDataFormat schema wrapper

Mapping(required=[])

Attributes:

parse : anyOf(enum(‘auto’), Parse, None)

If set to "auto" (the default), perform automatic type inference to determine the desired data types. If set to null, disable type inference based on the spec and only use type inference based on the data. Alternatively, a parsing directive object can be provided for explicit data types. Each property of the object corresponds to a field name, and the value to the desired data type (one of "number", "boolean", "date", or null (do not parse the field)). For example, "parse": {"modified_on": "date"} parses the modified_on field in each input record a Date value.

For "date", we parse data based using Javascript’s Date.parse(). For Specific date formats can be provided (e.g., {foo: 'date:"%m%d%Y"'} ), using the d3-time-format syntax. UTC date format parsing is supported similarly (e.g., {foo: 'utc:"%m%d%Y"'} ). See more about UTC time

property : string

The JSON property containing the desired data. This parameter can be used when the loaded JSON file may have surrounding structure or meta-data. For example "property": "values.features" is equivalent to retrieving json.values.features from the loaded JSON object.

type : enum(‘json’)

Type of input data: "json", "csv", "tsv", "dsv". The default format type is determined by the extension of the file URL. If no extension is detected, "json" will be used by default.

class altair.Key(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Key schema wrapper

Mapping(required=[shorthand]) Definition object for a data field, its type and transformation of an encoding channel.

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.Latitude(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Latitude schema wrapper

Mapping(required=[shorthand]) Definition object for a data field, its type and transformation of an encoding channel.

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.Latitude2(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Latitude2 schema wrapper

Mapping(required=[shorthand]) Definition object for a data field, its type and transformation of an encoding channel.

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.LayerSpec(layer=Undefined, data=Undefined, description=Undefined, encoding=Undefined, height=Undefined, name=Undefined, projection=Undefined, resolve=Undefined, title=Undefined, transform=Undefined, width=Undefined, **kwds)¶

LayerSpec schema wrapper

Mapping(required=[layer]) Layer Spec with encoding and projection

Attributes:

layer : List(anyOf(LayerSpec, CompositeUnitSpec))

Layer or single view specifications to be layered.

Note : Specifications inside layer cannot use row and column channels as layering facet specifications is not allowed.

data : Data

An object describing the data source

description : string

Description of this mark for commenting purpose.

encoding : Encoding

A shared key-value mapping between encoding channels and definition of fields in the underlying layers.

height : float

The height of a visualization.

Default value:

If a view’s autosize type is "fit" or its y-channel has a continuous scale, the height will be the value of config.view.height.
For y-axis with a band or point scale: if rangeStep is a numeric value or unspecified, the height is determined by the range step, paddings, and the cardinality of the field mapped to y-channel. Otherwise, if the rangeStep is null, the height will be the value of config.view.height.
If no field is mapped to y channel, the height will be the value of rangeStep.

Note : For plots with row and column channels, this represents the height of a single view.

See also: The documentation for width and height contains more examples.

name : string

Name of the visualization for later reference.

projection : Projection

An object defining properties of the geographic projection shared by underlying layers.

resolve : Resolve

Scale, axis, and legend resolutions for layers.

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

width : float

The width of a visualization.

Default value: This will be determined by the following rules:

If a view’s autosize type is "fit" or its x-channel has a continuous scale, the width will be the value of config.view.width.
For x-axis with a band or point scale: if rangeStep is a numeric value or unspecified, the width is determined by the range step, paddings, and the cardinality of the field mapped to x-channel. Otherwise, if the rangeStep is null, the width will be the value of config.view.width.
If no field is mapped to x channel, the width will be the value of config.scale.textXRangeStep for text mark and the value of rangeStep for other marks.

Note: For plots with row and column channels, this represents the width of a single view.

See also: The documentation for width and height contains more examples.

class altair.Legend(entryPadding=Undefined, format=Undefined, offset=Undefined, orient=Undefined, padding=Undefined, tickCount=Undefined, title=Undefined, type=Undefined, values=Undefined, zindex=Undefined, **kwds)¶

Legend schema wrapper

Mapping(required=[]) Properties of a legend or boolean flag for determining whether to show it.

Attributes:

entryPadding : float

Padding (in pixels) between legend entries in a symbol legend.

format : string

The formatting pattern for labels. This is D3’s number format pattern for quantitative fields and D3’s time format pattern for time field.

See the format documentation for more information.

Default value: derived from numberFormat config for quantitative fields and from timeFormat config for temporal fields.

offset : float

The offset, in pixels, by which to displace the legend from the edge of the enclosing group or data rectangle.

Default value: 0

orient : LegendOrient

The orientation of the legend, which determines how the legend is positioned within the scene. One of “left”, “right”, “top-left”, “top-right”, “bottom-left”, “bottom-right”, “none”.

Default value: "right"

padding : float

The padding, in pixels, between the legend and axis.

tickCount : float

The desired number of tick values for quantitative legends.

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : enum(‘symbol’, ‘gradient’)

The type of the legend. Use "symbol" to create a discrete legend and

<<<<<<< HEAD

"gradient" for a continuous color gradient.

Default value: "gradient" for non-binned quantitative fields and temporal fields; "symbol" otherwise.

values : anyOf(List(float), List(string), List(DateTime))

=======

"gradient" for a continuous color gradient. Default value: "gradient" for non-binned quantitative fields and temporal fields; "symbol" otherwise.

values : anyOf(List(float), List(string), List(boolean), List(DateTime))

>>>>>>> altair-viz/master

Explicitly set the visible legend values.

zindex : float: A non-positive integer indicating z-index of the legend. If zindex is 0, legend should be drawn behind all chart elements. To put them in front, use zindex = 1.

class altair.LegendConfig(cornerRadius=Undefined, entryPadding=Undefined, fillColor=Undefined, gradientHeight=Undefined, gradientLabelBaseline=Undefined, gradientLabelLimit=Undefined, gradientLabelOffset=Undefined, gradientStrokeColor=Undefined, gradientStrokeWidth=Undefined, gradientWidth=Undefined, labelAlign=Undefined, labelBaseline=Undefined, labelColor=Undefined, labelFont=Undefined, labelFontSize=Undefined, labelLimit=Undefined, labelOffset=Undefined, offset=Undefined, orient=Undefined, padding=Undefined, shortTimeLabels=Undefined, strokeColor=Undefined, strokeDash=Undefined, strokeWidth=Undefined, symbolColor=Undefined, symbolSize=Undefined, symbolStrokeWidth=Undefined, symbolType=Undefined, titleAlign=Undefined, titleBaseline=Undefined, titleColor=Undefined, titleFont=Undefined, titleFontSize=Undefined, titleFontWeight=Undefined, titleLimit=Undefined, titlePadding=Undefined, **kwds)¶

LegendConfig schema wrapper

Mapping(required=[])

Attributes:

cornerRadius : float

Corner radius for the full legend.

entryPadding : float

Padding (in pixels) between legend entries in a symbol legend.

fillColor : string

Background fill color for the full legend.

gradientHeight : float

The height of the gradient, in pixels.

gradientLabelBaseline : string

Text baseline for color ramp gradient labels.

gradientLabelLimit : float

The maximum allowed length in pixels of color ramp gradient labels.

gradientLabelOffset : float

Vertical offset in pixels for color ramp gradient labels.

gradientStrokeColor : string

The color of the gradient stroke, can be in hex color code or regular color name.

gradientStrokeWidth : float

The width of the gradient stroke, in pixels.

gradientWidth : float

The width of the gradient, in pixels.

labelAlign : string

The alignment of the legend label, can be left, middle or right.

labelBaseline : string

The position of the baseline of legend label, can be top, middle or bottom.

labelColor : string

The color of the legend label, can be in hex color code or regular color name.

labelFont : string

The font of the legend label.

labelFontSize : float

The font size of legend label.

Default value: 10.

labelLimit : float

Maximum allowed pixel width of axis tick labels.

labelOffset : float

The offset of the legend label.

offset : float

The offset, in pixels, by which to displace the legend from the edge of the enclosing group or data rectangle.

Default value: 0

orient : LegendOrient

The orientation of the legend, which determines how the legend is positioned within the scene. One of “left”, “right”, “top-left”, “top-right”, “bottom-left”, “bottom-right”, “none”.

Default value: "right"

padding : float

The padding, in pixels, between the legend and axis.

shortTimeLabels : boolean

Whether month names and weekday names should be abbreviated.

Default value: false

strokeColor : string

Border stroke color for the full legend.

strokeDash : List(float)

Border stroke dash pattern for the full legend.

strokeWidth : float

Border stroke width for the full legend.

symbolColor : string

The color of the legend symbol,

symbolSize : float

The size of the legend symbol, in pixels.

symbolStrokeWidth : float

The width of the symbol’s stroke.

symbolType : string

Default shape type (such as “circle”) for legend symbols.

titleAlign : string

Horizontal text alignment for legend titles.

titleBaseline : string

Vertical text baseline for legend titles.

titleColor : string

The color of the legend title, can be in hex color code or regular color name.

titleFont : string

The font of the legend title.

titleFontSize : float

The font size of the legend title.

titleFontWeight : FontWeight

The font weight of the legend title. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

titleLimit : float

Maximum allowed pixel width of axis titles.

titlePadding : float

The padding, in pixels, between title and legend.

class altair.LegendOrient(*args)¶

LegendOrient schema wrapper

enum(‘left’, ‘right’, ‘top-left’, ‘top-right’, ‘bottom-left’, ‘bottom-right’, ‘none’)

class altair.LegendResolveMap(color=Undefined, fill=Undefined, opacity=Undefined, shape=Undefined, size=Undefined, stroke=Undefined, **kwds)¶

LegendResolveMap schema wrapper

Mapping(required=[])

Attributes:	color : ResolveMode fill : ResolveMode opacity : ResolveMode shape : ResolveMode size : ResolveMode stroke : ResolveMode

class altair.LineConfig(align=Undefined, angle=Undefined, baseline=Undefined, color=Undefined, cornerRadius=Undefined, cursor=Undefined, dir=Undefined, dx=Undefined, dy=Undefined, ellipsis=Undefined, fill=Undefined, fillOpacity=Undefined, filled=Undefined, font=Undefined, fontSize=Undefined, fontStyle=Undefined, fontWeight=Undefined, href=Undefined, interpolate=Undefined, limit=Undefined, opacity=Undefined, orient=Undefined, point=Undefined, radius=Undefined, shape=Undefined, size=Undefined, stroke=Undefined, strokeCap=Undefined, strokeDash=Undefined, strokeDashOffset=Undefined, strokeJoin=Undefined, strokeMiterLimit=Undefined, strokeOpacity=Undefined, strokeWidth=Undefined, tension=Undefined, text=Undefined, theta=Undefined, tooltip=Undefined, **kwds)¶

LineConfig schema wrapper

Mapping(required=[])

Attributes:

align : HorizontalAlign

The horizontal alignment of the text. One of "left", "right", "center".

angle : float

The rotation angle of the text, in degrees.

baseline : VerticalAlign

The vertical alignment of the text. One of "top", "middle", "bottom".

Default value: "middle"

color : string

Default color. Note that fill and stroke have higher precedence than color and will override color.

Default value: ■ "#4682b4"

Note: This property cannot be used in a style config.

cornerRadius : float

The radius in pixels of rounded rectangle corners. Default value: 0

cursor : Cursor

The mouse cursor used over the mark. Any valid CSS cursor type can be used.

dir : Dir

The direction of the text. One of "ltr" (left-to-right) or "rtl" (right-to-left). This property determines on which side is truncated in response to the limit parameter. Default value: "ltr"

dx : float

The horizontal offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

dy : float

The vertical offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

ellipsis : string

The ellipsis string for text truncated in response to the limit parameter. Default value: "…"

fill : string

Default Fill Color. This has higher precedence than config.color

Default value: (None)

fillOpacity : float

The fill opacity (value between [0,1]).

Default value: 1

filled : boolean

Whether the mark’s color should be used as fill color instead of stroke color.

Default value: true for all marks except point and false for point.

Applicable for: bar, point, circle, square, and area marks.

Note: This property cannot be used in a style config.

font : string

The typeface to set the text in (e.g., "Helvetica Neue" ).

fontSize : float

The font size, in pixels.

fontStyle : FontStyle

The font style (e.g., "italic" ).

fontWeight : FontWeight

The font weight. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

href : string

A URL to load upon mouse click. If defined, the mark acts as a hyperlink.

interpolate : Interpolate

The line interpolation method to use for line and area marks. One of the following:

"linear" : piecewise linear segments, as in a polyline.
"linear-closed" : close the linear segments to form a polygon.
"step" : alternate between horizontal and vertical segments, as in a step function.
"step-before" : alternate between vertical and horizontal segments, as in a step function.
"step-after" : alternate between horizontal and vertical segments, as in a step function.
"basis" : a B-spline, with control point duplication on the ends.
"basis-open" : an open B-spline; may not intersect the start or end.
"basis-closed" : a closed B-spline, as in a loop.
"cardinal" : a Cardinal spline, with control point duplication on the ends.
"cardinal-open" : an open Cardinal spline; may not intersect the start or end, but will intersect other control points.
"cardinal-closed" : a closed Cardinal spline, as in a loop.
"bundle" : equivalent to basis, except the tension parameter is used to straighten the spline.
"monotone" : cubic interpolation that preserves monotonicity in y.

limit : float

The maximum length of the text mark in pixels. The text value will be automatically truncated if the rendered size exceeds the limit. Default value: 0, indicating no limit

opacity : float

The overall opacity (value between [0,1]).

Default value: 0.7 for non-aggregate plots with point, tick, circle, or square marks or layered bar charts and 1 otherwise.

orient : Orient

<<<<<<< HEAD

The orientation of a non-stacked bar, tick, area, and line charts. The value is either horizontal (default) or vertical.

For bar, rule and tick, this determines whether the size of the bar and tick

should be applied to x or y dimension. * For area, this property determines the orient property of the Vega output. * For line and trail marks, this property determines the sort order of the points in

the line

if config.sortLineBy is not specified. For stacked charts, this is always determined by the orientation of the stack; therefore explicitly specified value will be ignored.

point : anyOf(boolean, MarkConfig, enum(‘transparent’))

=======

The orientation of a non-stacked bar, tick, area, and line charts. The value is either horizontal (default) or vertical. * For bar, rule and tick, this determines

whether the size of the bar and tick should be applied to x or y dimension. * For area, this property determines the orient property of the Vega output. * For line

and trail marks, this property determines the sort order of the points in the line

if config.sortLineBy is not specified. For stacked charts, this is always

determined by the orientation of the stack; therefore explicitly specified value will be ignored.

point : anyOf(boolean, OverlayMarkDef, enum(‘transparent’))

>>>>>>> altair-viz/master

A flag for overlaying points on top of line or area marks, or an object defining the properties of the overlayed points.

If this property is "transparent", transparent points will be used (for enhancing tooltips and selections).

If this property is an empty object ( {} ) or true, filled points with default properties will be used.

If this property is false, no points would be automatically added to line or area marks.

Default value: false.

radius : float

Polar coordinate radial offset, in pixels, of the text label from the origin determined by the x and y properties.

shape : string

The default symbol shape to use. One of: "circle" (default), "square", "cross", "diamond", "triangle-up", or "triangle-down", or a custom SVG path.

Default value: "circle"

size : float

The pixel area each the point/circle/square. For example: in the case of circles, the radius is determined in part by the square root of the size value.

Default value: 30

stroke : string

<<<<<<< HEAD

Default Stroke Color. This has higher precedence than config.color

Default value: (None)

strokeCap : enum(‘butt’, ‘round’, ‘square’)

=======

Default Stroke Color. This has higher precedence than config.color Default value: (None)

strokeCap : StrokeCap

>>>>>>> altair-viz/master

The stroke cap for line ending style. One of "butt", "round", or "square".

Default value: "square"

strokeDash : List(float)

An array of alternating stroke, space lengths for creating dashed or dotted lines.

strokeDashOffset : float

The offset (in pixels) into which to begin drawing with the stroke dash array.

strokeJoin : StrokeJoin

The stroke line join method. One of "miter", "round" or "bevel". Default value: "miter"

strokeMiterLimit : float

The miter limit at which to bevel a line join.

strokeOpacity : float

The stroke opacity (value between [0,1]).

Default value: 1

strokeWidth : float

The stroke width, in pixels.

tension : float

Depending on the interpolation type, sets the tension parameter (for line and area marks).

text : string

Placeholder text if the text channel is not specified

theta : float

Polar coordinate angle, in radians, of the text label from the origin determined by the x and y properties. Values for theta follow the same convention of arc mark startAngle and endAngle properties: angles are measured in radians, with 0 indicating “north”.

tooltip : Mapping(required=[])

The tooltip text to show upon mouse hover.

class altair.LocalMultiTimeUnit(*args)¶

LocalMultiTimeUnit schema wrapper

enum(‘yearquarter’, ‘yearquartermonth’, ‘yearmonth’, ‘yearmonthdate’, ‘yearmonthdatehours’, ‘yearmonthdatehoursminutes’, ‘yearmonthdatehoursminutesseconds’, ‘quartermonth’, ‘monthdate’, ‘hoursminutes’, ‘hoursminutesseconds’, ‘minutesseconds’, ‘secondsmilliseconds’)

class altair.LocalSingleTimeUnit(*args)¶

LocalSingleTimeUnit schema wrapper

enum(‘year’, ‘quarter’, ‘month’, ‘day’, ‘date’, ‘hours’, ‘minutes’, ‘seconds’, ‘milliseconds’)

class altair.LogicalAndPredicate(**kwds)¶

LogicalAndPredicate schema wrapper

Mapping(required=[and])

Attributes:	and : List(LogicalOperandPredicate)

class altair.LogicalNotPredicate(**kwds)¶

LogicalNotPredicate schema wrapper

Mapping(required=[not])

Attributes:	not : LogicalOperandPredicate

class altair.LogicalOperandPredicate(*args, **kwds)¶

LogicalOperandPredicate schema wrapper

anyOf(LogicalNotPredicate, LogicalAndPredicate, LogicalOrPredicate, Predicate)

class altair.LogicalOrPredicate(**kwds)¶

LogicalOrPredicate schema wrapper

Mapping(required=[or])

Attributes:	or : List(LogicalOperandPredicate)

class altair.Longitude(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Longitude schema wrapper

Mapping(required=[shorthand]) Definition object for a data field, its type and transformation of an encoding channel.

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.Longitude2(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Longitude2 schema wrapper

Mapping(required=[shorthand]) Definition object for a data field, its type and transformation of an encoding channel.

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.LookupData(data=Undefined, key=Undefined, fields=Undefined, **kwds)¶

LookupData schema wrapper

Mapping(required=[data, key])

Attributes:	data : Data Secondary data source to lookup in. key : string Key in data to lookup. fields : List(string) Fields in foreign data to lookup. If not specified, the entire object is queried.

to_dict(*args, **kwargs)¶: Convert the chart to a dictionary suitable for JSON export

class altair.LookupTransform(lookup=Undefined, default=Undefined, **kwds)¶

LookupTransform schema wrapper

Mapping(required=[lookup, from])

Attributes:

lookup : string

Key in primary data source.

default : string

The default value to use if lookup fails.

Default value: null

as : anyOf(string, List(string))

The field or fields for storing the computed formula value. If from.fields is specified, the transform will use the same names for as. If from.fields is not specified, as has to be a string and we put the whole object into the data under the specified name.

from : LookupData

Secondary data reference.

class altair.Mark(*args)¶

Mark schema wrapper

enum(‘area’, ‘bar’, ‘line’, ‘trail’, ‘point’, ‘text’, ‘tick’, ‘rect’, ‘rule’, ‘circle’, ‘square’, ‘geoshape’) All types of primitive marks.

class altair.MarkConfig(align=Undefined, angle=Undefined, baseline=Undefined, color=Undefined, cornerRadius=Undefined, cursor=Undefined, dir=Undefined, dx=Undefined, dy=Undefined, ellipsis=Undefined, fill=Undefined, fillOpacity=Undefined, filled=Undefined, font=Undefined, fontSize=Undefined, fontStyle=Undefined, fontWeight=Undefined, href=Undefined, interpolate=Undefined, limit=Undefined, opacity=Undefined, orient=Undefined, radius=Undefined, shape=Undefined, size=Undefined, stroke=Undefined, strokeCap=Undefined, strokeDash=Undefined, strokeDashOffset=Undefined, strokeJoin=Undefined, strokeMiterLimit=Undefined, strokeOpacity=Undefined, strokeWidth=Undefined, tension=Undefined, text=Undefined, theta=Undefined, tooltip=Undefined, **kwds)¶

MarkConfig schema wrapper

Mapping(required=[])

Attributes:

align : HorizontalAlign

The horizontal alignment of the text. One of "left", "right", "center".

angle : float

The rotation angle of the text, in degrees.

baseline : VerticalAlign

The vertical alignment of the text. One of "top", "middle", "bottom".

Default value: "middle"

color : string

Default color. Note that fill and stroke have higher precedence than color and will override color.

Default value: ■ "#4682b4"

Note: This property cannot be used in a style config.

cornerRadius : float

The radius in pixels of rounded rectangle corners. Default value: 0

cursor : Cursor

The mouse cursor used over the mark. Any valid CSS cursor type can be used.

dir : Dir

The direction of the text. One of "ltr" (left-to-right) or "rtl" (right-to-left). This property determines on which side is truncated in response to the limit parameter. Default value: "ltr"

dx : float

The horizontal offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

dy : float

The vertical offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

ellipsis : string

The ellipsis string for text truncated in response to the limit parameter. Default value: "…"

fill : string

Default Fill Color. This has higher precedence than config.color

Default value: (None)

fillOpacity : float

The fill opacity (value between [0,1]).

Default value: 1

filled : boolean

Whether the mark’s color should be used as fill color instead of stroke color.

Default value: true for all marks except point and false for point.

Applicable for: bar, point, circle, square, and area marks.

Note: This property cannot be used in a style config.

font : string

The typeface to set the text in (e.g., "Helvetica Neue" ).

fontSize : float

The font size, in pixels.

fontStyle : FontStyle

The font style (e.g., "italic" ).

fontWeight : FontWeight

The font weight. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

href : string

A URL to load upon mouse click. If defined, the mark acts as a hyperlink.

interpolate : Interpolate

The line interpolation method to use for line and area marks. One of the following:

"linear" : piecewise linear segments, as in a polyline.
"linear-closed" : close the linear segments to form a polygon.
"step" : alternate between horizontal and vertical segments, as in a step function.
"step-before" : alternate between vertical and horizontal segments, as in a step function.
"step-after" : alternate between horizontal and vertical segments, as in a step function.
"basis" : a B-spline, with control point duplication on the ends.
"basis-open" : an open B-spline; may not intersect the start or end.
"basis-closed" : a closed B-spline, as in a loop.
"cardinal" : a Cardinal spline, with control point duplication on the ends.
"cardinal-open" : an open Cardinal spline; may not intersect the start or end, but will intersect other control points.
"cardinal-closed" : a closed Cardinal spline, as in a loop.
"bundle" : equivalent to basis, except the tension parameter is used to straighten the spline.
"monotone" : cubic interpolation that preserves monotonicity in y.

limit : float

The maximum length of the text mark in pixels. The text value will be automatically truncated if the rendered size exceeds the limit. Default value: 0, indicating no limit

opacity : float

The overall opacity (value between [0,1]).

Default value: 0.7 for non-aggregate plots with point, tick, circle, or square marks or layered bar charts and 1 otherwise.

orient : Orient

The orientation of a non-stacked bar, tick, area, and line charts. The value is either horizontal (default) or vertical.

For bar, rule and tick, this determines whether the size of the bar and tick

should be applied to x or y dimension. * For area, this property determines the orient property of the Vega output. * For line and trail marks, this property determines the sort order of the points in

the line

if config.sortLineBy is not specified. For stacked charts, this is always determined by the orientation of the stack; therefore explicitly specified value will be ignored.

radius : float

Polar coordinate radial offset, in pixels, of the text label from the origin determined by the x and y properties.

shape : string

The default symbol shape to use. One of: "circle" (default), "square", "cross", "diamond", "triangle-up", or "triangle-down", or a custom SVG path.

Default value: "circle"

size : float

The pixel area each the point/circle/square. For example: in the case of circles, the radius is determined in part by the square root of the size value.

Default value: 30

stroke : string

<<<<<<< HEAD

Default Stroke Color. This has higher precedence than config.color

Default value: (None)

strokeCap : enum(‘butt’, ‘round’, ‘square’)

=======

Default Stroke Color. This has higher precedence than config.color Default value: (None)

strokeCap : StrokeCap

>>>>>>> altair-viz/master

The stroke cap for line ending style. One of "butt", "round", or "square".

Default value: "square"

strokeDash : List(float)

An array of alternating stroke, space lengths for creating dashed or dotted lines.

strokeDashOffset : float

The offset (in pixels) into which to begin drawing with the stroke dash array.

strokeJoin : StrokeJoin

The stroke line join method. One of "miter", "round" or "bevel". Default value: "miter"

strokeMiterLimit : float

The miter limit at which to bevel a line join.

strokeOpacity : float

The stroke opacity (value between [0,1]).

Default value: 1

strokeWidth : float

The stroke width, in pixels.

tension : float

Depending on the interpolation type, sets the tension parameter (for line and area marks).

text : string

Placeholder text if the text channel is not specified

theta : float

Polar coordinate angle, in radians, of the text label from the origin determined by the x and y properties. Values for theta follow the same convention of arc mark startAngle and endAngle properties: angles are measured in radians, with 0 indicating “north”.

tooltip : Mapping(required=[])

The tooltip text to show upon mouse hover.

class altair.MarkDef(type=Undefined, align=Undefined, angle=Undefined, baseline=Undefined, binSpacing=Undefined, clip=Undefined, color=Undefined, cornerRadius=Undefined, cursor=Undefined, dir=Undefined, dx=Undefined, dy=Undefined, ellipsis=Undefined, fill=Undefined, fillOpacity=Undefined, filled=Undefined, font=Undefined, fontSize=Undefined, fontStyle=Undefined, fontWeight=Undefined, href=Undefined, interpolate=Undefined, limit=Undefined, line=Undefined, opacity=Undefined, orient=Undefined, point=Undefined, radius=Undefined, shape=Undefined, size=Undefined, stroke=Undefined, strokeCap=Undefined, strokeDash=Undefined, strokeDashOffset=Undefined, strokeJoin=Undefined, strokeMiterLimit=Undefined, strokeOpacity=Undefined, strokeWidth=Undefined, style=Undefined, tension=Undefined, text=Undefined, theta=Undefined, thickness=Undefined, tooltip=Undefined, x2Offset=Undefined, xOffset=Undefined, y2Offset=Undefined, yOffset=Undefined, **kwds)¶

MarkDef schema wrapper

Mapping(required=[type])

Attributes:

type : Mark

The mark type. One of "bar", "circle", "square", "tick", "line", "area", "point", "geoshape", "rule", and "text".

align : HorizontalAlign

The horizontal alignment of the text. One of "left", "right", "center".

angle : float

The rotation angle of the text, in degrees.

baseline : VerticalAlign

The vertical alignment of the text. One of "top", "middle", "bottom".

Default value: "middle"

binSpacing : float

Offset between bars for binned field. Ideal value for this is either 0 (Preferred by statisticians) or 1 (Vega-Lite Default, D3 example style).

Default value: 1

clip : boolean

Whether a mark be clipped to the enclosing group’s width and height.

color : string

Default color. Note that fill and stroke have higher precedence than color and will override color.

Default value: ■ "#4682b4"

Note: This property cannot be used in a style config.

cornerRadius : float

The radius in pixels of rounded rectangle corners. Default value: 0

cursor : Cursor

The mouse cursor used over the mark. Any valid CSS cursor type can be used.

dir : Dir

The direction of the text. One of "ltr" (left-to-right) or "rtl" (right-to-left). This property determines on which side is truncated in response to the limit parameter. Default value: "ltr"

dx : float

The horizontal offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

dy : float

The vertical offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

ellipsis : string

The ellipsis string for text truncated in response to the limit parameter. Default value: "…"

fill : string

Default Fill Color. This has higher precedence than config.color

Default value: (None)

fillOpacity : float

The fill opacity (value between [0,1]).

Default value: 1

filled : boolean

Whether the mark’s color should be used as fill color instead of stroke color.

Default value: true for all marks except point and false for point.

Applicable for: bar, point, circle, square, and area marks.

Note: This property cannot be used in a style config.

font : string

The typeface to set the text in (e.g., "Helvetica Neue" ).

fontSize : float

The font size, in pixels.

fontStyle : FontStyle

The font style (e.g., "italic" ).

fontWeight : FontWeight

The font weight. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

href : string

A URL to load upon mouse click. If defined, the mark acts as a hyperlink.

interpolate : Interpolate

The line interpolation method to use for line and area marks. One of the following:

"linear" : piecewise linear segments, as in a polyline.
"linear-closed" : close the linear segments to form a polygon.
"step" : alternate between horizontal and vertical segments, as in a step function.
"step-before" : alternate between vertical and horizontal segments, as in a step function.
"step-after" : alternate between horizontal and vertical segments, as in a step function.
"basis" : a B-spline, with control point duplication on the ends.
"basis-open" : an open B-spline; may not intersect the start or end.
"basis-closed" : a closed B-spline, as in a loop.
"cardinal" : a Cardinal spline, with control point duplication on the ends.
"cardinal-open" : an open Cardinal spline; may not intersect the start or end, but will intersect other control points.
"cardinal-closed" : a closed Cardinal spline, as in a loop.
"bundle" : equivalent to basis, except the tension parameter is used to straighten the spline.
"monotone" : cubic interpolation that preserves monotonicity in y.

limit : float

The maximum length of the text mark in pixels. The text value will be automatically truncated if the rendered size exceeds the limit. Default value: 0, indicating no limit

line : anyOf(boolean, OverlayMarkDef)

A flag for overlaying line on top of area marks, or an object defining the properties of the overlayed lines.

If this value is an empty object ( {} ) or true, lines with default properties will be used.

If this value is false, no lines would be automatically added to area marks.

Default value: false.

opacity : float

The overall opacity (value between [0,1]).

Default value: 0.7 for non-aggregate plots with point, tick, circle, or square marks or layered bar charts and 1 otherwise.

orient : Orient

<<<<<<< HEAD

The orientation of a non-stacked bar, tick, area, and line charts. The value is either horizontal (default) or vertical.

For bar, rule and tick, this determines whether the size of the bar and tick

should be applied to x or y dimension. * For area, this property determines the orient property of the Vega output. * For line and trail marks, this property determines the sort order of the points in

the line

if config.sortLineBy is not specified. For stacked charts, this is always determined by the orientation of the stack; therefore explicitly specified value will be ignored.

point : anyOf(boolean, MarkConfig, enum(‘transparent’))

=======

The orientation of a non-stacked bar, tick, area, and line charts. The value is either horizontal (default) or vertical. * For bar, rule and tick, this determines

whether the size of the bar and tick should be applied to x or y dimension. * For area, this property determines the orient property of the Vega output. * For line

and trail marks, this property determines the sort order of the points in the line

if config.sortLineBy is not specified. For stacked charts, this is always

determined by the orientation of the stack; therefore explicitly specified value will be ignored.

point : anyOf(boolean, OverlayMarkDef, enum(‘transparent’))

>>>>>>> altair-viz/master

A flag for overlaying points on top of line or area marks, or an object defining the properties of the overlayed points.

If this property is "transparent", transparent points will be used (for enhancing tooltips and selections).

If this property is an empty object ( {} ) or true, filled points with default properties will be used.

If this property is false, no points would be automatically added to line or area marks.

Default value: false.

radius : float

Polar coordinate radial offset, in pixels, of the text label from the origin determined by the x and y properties.

shape : string

The default symbol shape to use. One of: "circle" (default), "square", "cross", "diamond", "triangle-up", or "triangle-down", or a custom SVG path.

Default value: "circle"

size : float

The pixel area each the point/circle/square. For example: in the case of circles, the radius is determined in part by the square root of the size value.

Default value: 30

stroke : string

<<<<<<< HEAD

Default Stroke Color. This has higher precedence than config.color

Default value: (None)

strokeCap : enum(‘butt’, ‘round’, ‘square’)

=======

Default Stroke Color. This has higher precedence than config.color Default value: (None)

strokeCap : StrokeCap

>>>>>>> altair-viz/master

The stroke cap for line ending style. One of "butt", "round", or "square".

Default value: "square"

strokeDash : List(float)

An array of alternating stroke, space lengths for creating dashed or dotted lines.

strokeDashOffset : float

The offset (in pixels) into which to begin drawing with the stroke dash array.

strokeJoin : StrokeJoin

The stroke line join method. One of "miter", "round" or "bevel". Default value: "miter"

strokeMiterLimit : float

The miter limit at which to bevel a line join.

strokeOpacity : float

The stroke opacity (value between [0,1]).

Default value: 1

strokeWidth : float

The stroke width, in pixels.

style : anyOf(string, List(string))

A string or array of strings indicating the name of custom styles to apply to the mark. A style is a named collection of mark property defaults defined within the style configuration. If style is an array, later styles will override earlier styles. Any mark properties explicitly defined within the encoding will override a style default.

Default value: The mark’s name. For example, a bar mark will have style "bar" by default. Note: Any specified style will augment the default style. For example, a bar mark with "style": "foo" will receive from config.style.bar and config.style.foo (the specified style "foo" has higher precedence).

tension : float

Depending on the interpolation type, sets the tension parameter (for line and area marks).

text : string

Placeholder text if the text channel is not specified

theta : float

Polar coordinate angle, in radians, of the text label from the origin determined by the x and y properties. Values for theta follow the same convention of arc mark startAngle and endAngle properties: angles are measured in radians, with 0 indicating “north”.

thickness : float

<<<<<<< HEAD

Thickness of the tick mark.

Default value: 1

=======

Thickness of the tick mark. Default value: 1

tooltip : Mapping(required=[]): The tooltip text to show upon mouse hover.

>>>>>>> altair-viz/master

x2Offset : float: Offset for x2-position.
xOffset : float: Offset for x-position.
y2Offset : float: Offset for y2-position.
yOffset : float: Offset for y-position.

class altair.MarkPropFieldDefWithCondition(type=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, legend=Undefined, scale=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, **kwds)¶

MarkPropFieldDefWithCondition schema wrapper

Mapping(required=[type]) A FieldDef with Condition

Attributes:

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

legend : anyOf(Legend, None)

An object defining properties of the legend. If null, the legend for the encoding channel will be removed.

Default value: If undefined, default legend properties are applied.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

<<<<<<< HEAD

sort : anyOf(List(string), SortOrder, EncodingSortField, None)

Sort order for the encoded field. Supported sort values include "ascending", "descending", null (no sorting), or an array specifying the preferred order of values. For fields with discrete domains, sort can also be a sort field definition object. For sort as an array specifying the preferred order of values, the sort order will obey the values in the array, followed by any unspecified values in their original order.

Default value: "ascending"

=======

sort : Sort

Sort order for the encoded field. For continuous fields (quantitative or temporal),: sort can be either "ascending" or "descending". For discrete fields,
sort can be one of the following: * "ascending" or "descending" – for: sorting by the values’ natural order in Javascript. * `A sort field definition

<https://vega.github.io/vega-lite/docs/sort.html#sort-field>`_ for sorting by another field. * An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ). * null indicating no sort. Default value: "ascending" Note: null is not supported for row and column.

>>>>>>> altair-viz/master

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

class altair.MarkPropValueDefWithCondition(condition=Undefined, value=Undefined, **kwds)¶

MarkPropValueDefWithCondition schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalMarkPropFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.Month(*args)¶

Month schema wrapper

float

class altair.MultiSelection(type=Undefined, empty=Undefined, encodings=Undefined, fields=Undefined, nearest=Undefined, on=Undefined, resolve=Undefined, toggle=Undefined, **kwds)¶

MultiSelection schema wrapper

Mapping(required=[type])

Attributes:

type : enum(‘multi’)

empty : enum(‘all’, ‘none’)

By default, all data values are considered to lie within an empty selection. When set to none, empty selections contain no data values.

encodings : List(SingleDefChannel)

An array of encoding channels. The corresponding data field values must match for a data tuple to fall within the selection.

fields : List(string)

An array of field names whose values must match for a data tuple to fall within the selection.

nearest : boolean

When true, an invisible voronoi diagram is computed to accelerate discrete selection. The data value nearest the mouse cursor is added to the selection.

See the nearest transform documentation for more information.

on : VgEventStream

A Vega event stream (object or selector) that triggers the selection. For interval selections, the event stream must specify a start and end.

resolve : SelectionResolution

With layered and multi-view displays, a strategy that determines how selections’ data queries are resolved when applied in a filter transform, conditional encoding rule, or scale domain.

toggle : anyOf(string, boolean)

Controls whether data values should be toggled or only ever inserted into multi selections. Can be true, false (for insertion only), or a Vega expression.

Default value: true, which corresponds to event.shiftKey (i.e., data values are toggled when a user interacts with the shift-key pressed).

See the toggle transform documentation for more information.

class altair.MultiSelectionConfig(empty=Undefined, encodings=Undefined, fields=Undefined, nearest=Undefined, on=Undefined, resolve=Undefined, toggle=Undefined, **kwds)¶

MultiSelectionConfig schema wrapper

Mapping(required=[])

Attributes:

empty : enum(‘all’, ‘none’)

By default, all data values are considered to lie within an empty selection. When set to none, empty selections contain no data values.

encodings : List(SingleDefChannel)

An array of encoding channels. The corresponding data field values must match for a data tuple to fall within the selection.

fields : List(string)

An array of field names whose values must match for a data tuple to fall within the selection.

nearest : boolean

When true, an invisible voronoi diagram is computed to accelerate discrete selection. The data value nearest the mouse cursor is added to the selection.

See the nearest transform documentation for more information.

on : VgEventStream

A Vega event stream (object or selector) that triggers the selection. For interval selections, the event stream must specify a start and end.

resolve : SelectionResolution

With layered and multi-view displays, a strategy that determines how selections’ data queries are resolved when applied in a filter transform, conditional encoding rule, or scale domain.

toggle : anyOf(string, boolean)

Controls whether data values should be toggled or only ever inserted into multi selections. Can be true, false (for insertion only), or a Vega expression.

Default value: true, which corresponds to event.shiftKey (i.e., data values are toggled when a user interacts with the shift-key pressed).

See the toggle transform documentation for more information.

class altair.MultiTimeUnit(*args, **kwds)¶

MultiTimeUnit schema wrapper

anyOf(LocalMultiTimeUnit, UtcMultiTimeUnit)

class altair.NamedData(name=Undefined, format=Undefined, **kwds)¶

NamedData schema wrapper

Mapping(required=[name])

Attributes:	name : string Provide a placeholder name and bind data at runtime. format : DataFormat An object that specifies the format for parsing the data.

class altair.NamedSelection(*args, **kwds)¶

A SelectionMapping with a single named selection item

ref()¶

Return a selection reference to this object

Examples

>>> import altair as alt
>>> sel = alt.selection_interval(name='interval')
>>> sel.ref()
{'selection': 'interval'}

class altair.NiceTime(*args)¶

NiceTime schema wrapper

enum(‘second’, ‘minute’, ‘hour’, ‘day’, ‘week’, ‘month’, ‘year’)

class altair.Opacity(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, legend=Undefined, scale=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

Opacity schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

legend : anyOf(Legend, None)

An object defining properties of the legend. If null, the legend for the encoding channel will be removed.

Default value: If undefined, default legend properties are applied.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.OpacityValue(value, condition=Undefined, **kwds)

OpacityValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalMarkPropFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.Order(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

Order schema wrapper

Mapping(required=[shorthand])

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

sort : SortOrder

The sort order. One of "ascending" (default) or "descending".

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.OrderFieldDef(type=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, **kwds)¶

OrderFieldDef schema wrapper

Mapping(required=[type])

Attributes:

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

sort : SortOrder

The sort order. One of "ascending" (default) or "descending".

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

class altair.OrderValue(value, **kwds)¶

OrderValue schema wrapper

Mapping(required=[value]) Definition object for a constant value of an encoding channel.

Attributes:	value : anyOf(float, string, boolean) A constant value in visual domain (e.g., `"red"` / “#0099ff” for color, values between `0` to `1` for opacity).

class altair.Orient(*args)¶

Orient schema wrapper

enum(‘horizontal’, ‘vertical’)

class altair.OverlayMarkDef(align=Undefined, angle=Undefined, baseline=Undefined, clip=Undefined, color=Undefined, cornerRadius=Undefined, cursor=Undefined, dir=Undefined, dx=Undefined, dy=Undefined, ellipsis=Undefined, fill=Undefined, fillOpacity=Undefined, filled=Undefined, font=Undefined, fontSize=Undefined, fontStyle=Undefined, fontWeight=Undefined, href=Undefined, interpolate=Undefined, limit=Undefined, opacity=Undefined, orient=Undefined, radius=Undefined, shape=Undefined, size=Undefined, stroke=Undefined, strokeCap=Undefined, strokeDash=Undefined, strokeDashOffset=Undefined, strokeJoin=Undefined, strokeMiterLimit=Undefined, strokeOpacity=Undefined, strokeWidth=Undefined, style=Undefined, tension=Undefined, text=Undefined, theta=Undefined, tooltip=Undefined, x2Offset=Undefined, xOffset=Undefined, y2Offset=Undefined, yOffset=Undefined, **kwds)¶

OverlayMarkDef schema wrapper

Mapping(required=[])

Attributes:

align : HorizontalAlign

The horizontal alignment of the text. One of "left", "right", "center".

angle : float

The rotation angle of the text, in degrees.

baseline : VerticalAlign

The vertical alignment of the text. One of "top", "middle", "bottom". Default value: "middle"

clip : boolean

Whether a mark be clipped to the enclosing group’s width and height.

color : string

Default color. Note that fill and stroke have higher precedence than color and will override color. Default value: ■ "#4682b4" Note: This property cannot be used in a style config.

cornerRadius : float

The radius in pixels of rounded rectangle corners. Default value: 0

cursor : Cursor

The mouse cursor used over the mark. Any valid CSS cursor type can be used.

dir : Dir

The direction of the text. One of "ltr" (left-to-right) or "rtl" (right-to-left). This property determines on which side is truncated in response to the limit parameter. Default value: "ltr"

dx : float

The horizontal offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

dy : float

The vertical offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

ellipsis : string

The ellipsis string for text truncated in response to the limit parameter. Default value: "…"

fill : string

Default Fill Color. This has higher precedence than config.color Default value: (None)

fillOpacity : float

The fill opacity (value between [0,1]). Default value: 1

filled : boolean

Whether the mark’s color should be used as fill color instead of stroke color. Default value: true for all marks except point and false for point. Applicable for: bar, point, circle, square, and area marks. Note: This property cannot be used in a style config.

font : string

The typeface to set the text in (e.g., "Helvetica Neue" ).

fontSize : float

The font size, in pixels.

fontStyle : FontStyle

The font style (e.g., "italic" ).

fontWeight : FontWeight

The font weight. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

href : string

A URL to load upon mouse click. If defined, the mark acts as a hyperlink.

interpolate : Interpolate

The line interpolation method to use for line and area marks. One of the following:

"linear" : piecewise linear segments, as in a polyline. *

"linear-closed" : close the linear segments to form a polygon. * "step" : alternate between horizontal and vertical segments, as in a step function. * "step-before" : alternate between vertical and horizontal segments, as in a step

function. * "step-after" : alternate between horizontal and vertical segments,

as in a step function. * "basis" : a B-spline, with control point duplication on: the ends. * "basis-open" : an open B-spline; may not intersect the start or

end. * "basis-closed" : a closed B-spline, as in a loop. * "cardinal" : a Cardinal spline, with control point duplication on the ends. * "cardinal-open" :

an open Cardinal spline; may not intersect the start or end, but will intersect

other control points. * "cardinal-closed" : a closed Cardinal spline, as in a loop. * "bundle" : equivalent to basis, except the tension parameter is used to straighten the spline. * "monotone" : cubic interpolation that preserves monotonicity in y.

limit : float

The maximum length of the text mark in pixels. The text value will be automatically truncated if the rendered size exceeds the limit. Default value: 0, indicating no limit

opacity : float

The overall opacity (value between [0,1]). Default value: 0.7 for non-aggregate plots with point, tick, circle, or square marks or layered bar charts and 1 otherwise.

orient : Orient

The orientation of a non-stacked bar, tick, area, and line charts. The value is either horizontal (default) or vertical. * For bar, rule and tick, this determines

whether the size of the bar and tick should be applied to x or y dimension. * For area, this property determines the orient property of the Vega output. * For line

and trail marks, this property determines the sort order of the points in the line: if config.sortLineBy is not specified. For stacked charts, this is always

determined by the orientation of the stack; therefore explicitly specified value will be ignored.

radius : float

Polar coordinate radial offset, in pixels, of the text label from the origin determined by the x and y properties.

shape : string

The default symbol shape to use. One of: "circle" (default), "square", "cross", "diamond", "triangle-up", or "triangle-down", or a custom SVG path. Default value: "circle"

size : float

The pixel area each the point/circle/square. For example: in the case of circles, the radius is determined in part by the square root of the size value. Default value: 30

stroke : string

Default Stroke Color. This has higher precedence than config.color Default value: (None)

strokeCap : StrokeCap

The stroke cap for line ending style. One of "butt", "round", or "square". Default value: "square"

strokeDash : List(float)

An array of alternating stroke, space lengths for creating dashed or dotted lines.

strokeDashOffset : float

The offset (in pixels) into which to begin drawing with the stroke dash array.

strokeJoin : StrokeJoin

The stroke line join method. One of "miter", "round" or "bevel". Default value: "miter"

strokeMiterLimit : float

The miter limit at which to bevel a line join.

strokeOpacity : float

The stroke opacity (value between [0,1]). Default value: 1

strokeWidth : float

The stroke width, in pixels.

style : anyOf(string, List(string))

A string or array of strings indicating the name of custom styles to apply to the mark. A style is a named collection of mark property defaults defined within the style configuration. If style is an array, later styles will override earlier styles. Any mark properties explicitly defined

within the encoding will override a style default. Default value: The

mark’s name. For example, a bar mark will have style "bar" by default. Note: Any specified style will augment the default style. For example, a bar mark with "style": "foo" will receive from config.style.bar and config.style.foo (the specified style "foo" has higher precedence).

tension : float

Depending on the interpolation type, sets the tension parameter (for line and area marks).

text : string

Placeholder text if the text channel is not specified

theta : float

Polar coordinate angle, in radians, of the text label from the origin determined by the x and y properties. Values for theta follow the same convention of arc mark startAngle and endAngle properties: angles are measured in radians, with 0 indicating “north”.

tooltip : Mapping(required=[])

The tooltip text to show upon mouse hover.

x2Offset : float

Offset for x2-position.

xOffset : float

Offset for x-position.

y2Offset : float

Offset for y2-position.

yOffset : float

Offset for y-position.

class altair.Padding(*args, **kwds)¶

Padding schema wrapper

anyOf(float, Mapping(required=[]))

class altair.Parse(**kwds)¶

Parse schema wrapper

Mapping(required=[])

class altair.PositionFieldDef(type=Undefined, aggregate=Undefined, axis=Undefined, bin=Undefined, field=Undefined, scale=Undefined, sort=Undefined, stack=Undefined, timeUnit=Undefined, title=Undefined, **kwds)¶

PositionFieldDef schema wrapper

Mapping(required=[type])

Attributes:

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

axis : anyOf(Axis, None)

An object defining properties of axis’s gridlines, ticks and labels. If null, the axis for the encoding channel will be removed.

Default value: If undefined, default axis properties are applied.

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

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sort : anyOf(List(string), SortOrder, EncodingSortField, None)

Sort order for the encoded field. Supported sort values include "ascending", "descending", null (no sorting), or an array specifying the preferred order of values. For fields with discrete domains, sort can also be a sort field definition object. For sort as an array specifying the preferred order of values, the sort order will obey the values in the array, followed by any unspecified values in their original order.

Default value: "ascending"

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sort : Sort

Sort order for the encoded field. For continuous fields (quantitative or temporal),: sort can be either "ascending" or "descending". For discrete fields,
sort can be one of the following: * "ascending" or "descending" – for: sorting by the values’ natural order in Javascript. * `A sort field definition

<https://vega.github.io/vega-lite/docs/sort.html#sort-field>`_ for sorting by another field. * An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ). * null indicating no sort. Default value: "ascending" Note: null is not supported for row and column.

>>>>>>> altair-viz/master

stack : anyOf(StackOffset, None)

Type of stacking offset if the field should be stacked. stack is only applicable for x and y channels with continuous domains. For example, stack of y can be used to customize stacking for a vertical bar chart.

stack can be one of the following values:

“zero”: stacking with baseline offset at zero value of the scale (for creating typical stacked [bar](https://vega.github.io/vega-lite/docs/stack.html#bar) and area chart).
"normalize" - stacking with normalized domain (for creating normalized stacked bar and area charts.

"center" - stacking with center baseline (for `streamgraph

<https://vega.github.io/vega-lite/docs/stack.html#streamgraph>`_ ). * null - No-stacking. This will produce layered `bar

<https://vega.github.io/vega-lite/docs/stack.html#layered-bar-chart>`_ and area chart.

Default value: zero for plots with all of the following conditions are true: (1) the mark is bar or area ; (2) the stacked measure channel (x or y) has a linear scale; (3) At least one of non-position channels mapped to an unaggregated field that is different from x and y. Otherwise, null by default.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

class altair.Predicate(*args, **kwds)¶

Predicate schema wrapper

anyOf(FieldEqualPredicate, FieldRangePredicate, FieldOneOfPredicate, FieldLTPredicate, FieldGTPredicate, FieldLTEPredicate, FieldGTEPredicate, SelectionPredicate, string)

class altair.Projection(center=Undefined, clipAngle=Undefined, clipExtent=Undefined, coefficient=Undefined, distance=Undefined, fraction=Undefined, lobes=Undefined, parallel=Undefined, precision=Undefined, radius=Undefined, ratio=Undefined, rotate=Undefined, spacing=Undefined, tilt=Undefined, type=Undefined, **kwds)¶

Projection schema wrapper

Mapping(required=[])

Attributes:

center : List(float)

Sets the projection’s center to the specified center, a two-element array of longitude and latitude in degrees.

Default value: [0, 0]

clipAngle : float

Sets the projection’s clipping circle radius to the specified angle in degrees. If null, switches to antimeridian cutting rather than small-circle clipping.

clipExtent : List(List(float))

Sets the projection’s viewport clip extent to the specified bounds in pixels. The extent bounds are specified as an array [[x0, y0], [x1, y1]], where x0 is the left-side of the viewport, y0 is the top, x1 is the right and y1 is the bottom. If null, no viewport clipping is performed.

coefficient : float

distance : float

fraction : float

lobes : float

parallel : float

precision : Mapping(required=[length])

Sets the threshold for the projection’s adaptive resampling to the specified value in pixels. This value corresponds to the Douglas–Peucker distance. If precision is not specified, returns the projection’s current resampling precision which defaults to √0.5 ≅ 0.70710….

radius : float

ratio : float

rotate : List(float)

Sets the projection’s three-axis rotation to the specified angles, which must be a two- or three-element array of numbers [ lambda, phi, gamma ] specifying the rotation angles in degrees about each spherical axis. (These correspond to yaw, pitch and roll.)

Default value: [0, 0, 0]

spacing : float

tilt : float

type : ProjectionType

The cartographic projection to use. This value is case-insensitive, for example "albers" and "Albers" indicate the same projection type. You can find all valid projection types in the documentation.

Default value: mercator

class altair.ProjectionConfig(center=Undefined, clipAngle=Undefined, clipExtent=Undefined, coefficient=Undefined, distance=Undefined, fraction=Undefined, lobes=Undefined, parallel=Undefined, precision=Undefined, radius=Undefined, ratio=Undefined, rotate=Undefined, spacing=Undefined, tilt=Undefined, type=Undefined, **kwds)¶

ProjectionConfig schema wrapper

Mapping(required=[]) Any property of Projection can be in config

Attributes:

center : List(float)

Sets the projection’s center to the specified center, a two-element array of longitude and latitude in degrees.

Default value: [0, 0]

clipAngle : float

Sets the projection’s clipping circle radius to the specified angle in degrees. If null, switches to antimeridian cutting rather than small-circle clipping.

clipExtent : List(List(float))

Sets the projection’s viewport clip extent to the specified bounds in pixels. The extent bounds are specified as an array [[x0, y0], [x1, y1]], where x0 is the left-side of the viewport, y0 is the top, x1 is the right and y1 is the bottom. If null, no viewport clipping is performed.

coefficient : float

distance : float

fraction : float

lobes : float

parallel : float

precision : Mapping(required=[length])

Sets the threshold for the projection’s adaptive resampling to the specified value in pixels. This value corresponds to the Douglas–Peucker distance. If precision is not specified, returns the projection’s current resampling precision which defaults to √0.5 ≅ 0.70710….

radius : float

ratio : float

rotate : List(float)

Sets the projection’s three-axis rotation to the specified angles, which must be a two- or three-element array of numbers [ lambda, phi, gamma ] specifying the rotation angles in degrees about each spherical axis. (These correspond to yaw, pitch and roll.)

Default value: [0, 0, 0]

spacing : float

tilt : float

type : ProjectionType

The cartographic projection to use. This value is case-insensitive, for example "albers" and "Albers" indicate the same projection type. You can find all valid projection types in the documentation.

Default value: mercator

class altair.ProjectionType(*args)¶

ProjectionType schema wrapper

enum(‘albers’, ‘albersUsa’, ‘azimuthalEqualArea’, ‘azimuthalEquidistant’, ‘conicConformal’, ‘conicEqualArea’, ‘conicEquidistant’, ‘equirectangular’, ‘gnomonic’, ‘mercator’, ‘orthographic’, ‘stereographic’, ‘transverseMercator’)

class altair.RangeConfig(category=Undefined, diverging=Undefined, heatmap=Undefined, ordinal=Undefined, ramp=Undefined, symbol=Undefined, **kwds)¶

RangeConfig schema wrapper

Mapping(required=[])

Attributes:

category : anyOf(List(string), VgScheme): Default range for nominal (categorical) fields.
diverging : anyOf(List(string), VgScheme): Default range for diverging quantitative fields.
heatmap : anyOf(List(string), VgScheme): Default range for quantitative heatmaps.
ordinal : anyOf(List(string), VgScheme): Default range for ordinal fields.
ramp : anyOf(List(string), VgScheme): Default range for quantitative and temporal fields.
symbol : List(string): Default range palette for the shape channel.

class altair.RangeConfigValue(*args, **kwds)¶

RangeConfigValue schema wrapper

anyOf(List(anyOf(float, string)), VgScheme, Mapping(required=[step]))

class altair.Repeat(column=Undefined, row=Undefined, **kwds)¶

Repeat schema wrapper

Mapping(required=[])

Attributes:	column : List(string) Horizontal repeated views. row : List(string) Vertical repeated views.

class altair.RepeatChart(data=Undefined, spec=Undefined, repeat=Undefined, **kwargs)

A chart repeated across rows and columns with small changes: Mapping(required=[repeat, spec])

Attributes:

repeat : Repeat

Return a RepeatChart built from the chart

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CSS color property to use as the background of visualization.

Default value: none (transparent)

=======

CSS color property to use as the background of visualization. Default value: none (transparent)

bounds : enum(‘full’, ‘flush’): The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"
center : anyOf(boolean, RowColboolean): Boolean flag indicating if subviews should be centered relative to their respective rows or columns. An object value of the form {"row": boolean, "column": boolean} can be used to supply different centering values for rows and columns. Default value: false

>>>>>>> altair-viz/master

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

data : Data

An object describing the data source

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

resolve : Resolve

Scale and legend resolutions for repeated charts.

spacing : anyOf(float, RowColnumber)

The spacing in pixels between sub-views of the composition operator. An object of the form {"row": number, "column": number} can be used to set different spacing values for rows and columns. Default value : 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

$schema : string

URL to JSON schema for a Vega-Lite specification. Unless you have a reason to change this, use https://vega.github.io/schema/vega-lite/v2.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

interactive(name=None, bind_x=True, bind_y=True)

Make chart axes scales interactive

Parameters:	name : string The selection name to use for the axes scales. This name should be unique among all selections within the chart. bind_x : boolean, default True If true, then bind the interactive scales to the x-axis bind_y : boolean, default True If true, then bind the interactive scales to the y-axis
Returns:	chart : copy of self, with interactive axes added

class altair.RepeatRef(repeat=Undefined, **kwds)¶

RepeatRef schema wrapper

Mapping(required=[repeat]) Reference to a repeated value.

Attributes:	repeat : enum(‘row’, ‘column’)

class altair.RepeatSpec(repeat=Undefined, spec=Undefined, align=Undefined, bounds=Undefined, center=Undefined, data=Undefined, description=Undefined, name=Undefined, resolve=Undefined, spacing=Undefined, title=Undefined, transform=Undefined, **kwds)¶

RepeatSpec schema wrapper

Mapping(required=[repeat, spec])

Attributes:

repeat : Repeat

An object that describes what fields should be repeated into views that are laid out as a row or column.

spec : Spec

align : anyOf(VgLayoutAlign, RowColVgLayoutAlign)

The alignment to apply to grid rows and columns. The supported string values are "all", "each", and "none". * For "none", a flow layout will be used, in which adjacent subviews are simply placed one after the other. * For "each", subviews will be aligned into a clean grid structure, but each row or column may be of variable size. * For "all", subviews will be aligned and each row or column will be sized identically based on the maximum observed size. String values for this property will be applied to both grid rows and columns. Alternatively, an object value of the form {"row": string, "column": string} can

be used to supply different alignments for rows and columns. Default value:

"all".

bounds : enum(‘full’, ‘flush’)

The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"

center : anyOf(boolean, RowColboolean)

Boolean flag indicating if subviews should be centered relative to their respective rows or columns. An object value of the form {"row": boolean, "column": boolean} can be used to supply different centering values for rows and columns. Default value: false

data : Data

An object describing the data source

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

resolve : Resolve

Scale and legend resolutions for repeated charts.

spacing : anyOf(float, RowColnumber)

The spacing in pixels between sub-views of the composition operator. An object of the form {"row": number, "column": number} can be used to set different spacing values for rows and columns. Default value : 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

class altair.Resolve(axis=Undefined, legend=Undefined, scale=Undefined, **kwds)¶

Resolve schema wrapper

Mapping(required=[]) Defines how scales, axes, and legends from different specs should be combined. Resolve is a mapping from scale, axis, and legend to a mapping from channels to resolutions.

Attributes:	axis : AxisResolveMap legend : LegendResolveMap scale : ScaleResolveMap

class altair.ResolveMode(*args)¶

ResolveMode schema wrapper

enum(‘independent’, ‘shared’)

class altair.Root(*args, **kwds)¶

Root schema wrapper

anyOf(TopLevelFacetedUnitSpec, TopLevelFacetSpec, TopLevelLayerSpec, TopLevelRepeatSpec, TopLevelVConcatSpec, TopLevelHConcatSpec)

class altair.Row(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, header=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

Row schema wrapper

Mapping(required=[shorthand])

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

header : Header

An object defining properties of a facet’s header.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.RowColVgLayoutAlign(column=Undefined, row=Undefined, **kwds)¶

RowColVgLayoutAlign schema wrapper

Mapping(required=[])

Attributes:	column : VgLayoutAlign row : VgLayoutAlign

class altair.RowColboolean(column=Undefined, row=Undefined, **kwds)¶

RowColboolean schema wrapper

Mapping(required=[])

Attributes:	column : boolean row : boolean

class altair.RowColnumber(column=Undefined, row=Undefined, **kwds)¶

RowColnumber schema wrapper

Mapping(required=[])

Attributes:	column : float row : float

class altair.Scale(base=Undefined, clamp=Undefined, domain=Undefined, exponent=Undefined, interpolate=Undefined, nice=Undefined, padding=Undefined, paddingInner=Undefined, paddingOuter=Undefined, range=Undefined, rangeStep=Undefined, round=Undefined, scheme=Undefined, type=Undefined, zero=Undefined, **kwds)¶

Scale schema wrapper

Mapping(required=[])

Attributes:

base : float

The logarithm base of the log scale (default 10 ).

clamp : boolean

If true, values that exceed the data domain are clamped to either the minimum or maximum range value

Default value: derived from the scale config ‘s clamp ( true by default).

domain : anyOf(List(float), List(string), List(boolean), List(DateTime),

enum(‘unaggregated’), SelectionDomain)

Customized domain values.

For quantitative fields, domain can take the form of a two-element array with minimum and maximum values. Piecewise scales can be created by providing a domain with more than two entries. If the input field is aggregated, domain can also be a string value "unaggregated", indicating that the domain should include the raw data values prior to the aggregation.

For temporal fields, domain can be a two-element array minimum and maximum values, in the form of either timestamps or the DateTime definition objects.

For ordinal and nominal fields, domain can be an array that lists valid input values.

The selection property can be used to interactively determine the scale domain.

exponent : float

The exponent of the pow scale.

interpolate : anyOf(ScaleInterpolate, ScaleInterpolateParams)

The interpolation method for range values. By default, a general interpolator for numbers, dates, strings and colors (in RGB space) is used. For color ranges, this property allows interpolation in alternative color spaces. Legal values include rgb, hsl, hsl-long, lab, hcl, hcl-long, cubehelix and cubehelix-long (‘-long’ variants use longer paths in polar coordinate spaces). If object-valued, this property accepts an object with a string-valued type property and an optional numeric gamma property applicable to rgb and cubehelix interpolators. For more, see the d3-interpolate documentation.

Note: Sequential scales do not support interpolate as they have a fixed interpolator. Since Vega-Lite uses sequential scales for quantitative fields by default, you have to set the scale type to other quantitative scale type such as "linear" to customize interpolate.

nice : anyOf(boolean, float, NiceTime, Mapping(required=[interval, step]))

Extending the domain so that it starts and ends on nice round values. This method typically modifies the scale’s domain, and may only extend the bounds to the nearest round value. Nicing is useful if the domain is computed from data and may be irregular. For example, for a domain of [0.201479…, 0.996679…], a nice domain might be [0.2, 1.0].

For quantitative scales such as linear, nice can be either a boolean flag or a number. If nice is a number, it will represent a desired tick count. This allows greater control over the step size used to extend the bounds, guaranteeing that the returned ticks will exactly cover the domain.

For temporal fields with time and utc scales, the nice value can be a string indicating the desired time interval. Legal values are "millisecond", "second", "minute", "hour", "day", "week", "month", and "year". Alternatively, time and utc scales can accept an object-valued interval specifier of the form {"interval": "month", "step": 3}, which includes a desired number of interval steps. Here, the domain would snap to quarter (Jan, Apr, Jul, Oct) boundaries.

Default value: true for unbinned quantitative fields; false otherwise.

padding : float

For * continuous * scales, expands the scale domain to accommodate the specified number of pixels on each of the scale range. The scale range must represent pixels for this parameter to function as intended. Padding adjustment is performed prior to all other adjustments, including the effects of the zero, nice, domainMin, and domainMax properties.

For * band * scales, shortcut for setting paddingInner and paddingOuter to the same value.

For * point * scales, alias for paddingOuter.

Default value: For continuous scales, derived from the scale config ‘s continuousPadding. For band and point scales, see paddingInner and paddingOuter.

paddingInner : float

The inner padding (spacing) within each band step of band scales, as a fraction of the step size. This value must lie in the range [0,1].

For point scale, this property is invalid as point scales do not have internal band widths (only step sizes between bands).

Default value: derived from the scale config ‘s bandPaddingInner.

paddingOuter : float

The outer padding (spacing) at the ends of the range of band and point scales, as a fraction of the step size. This value must lie in the range [0,1].

Default value: derived from the scale config ‘s bandPaddingOuter for band scales and pointPadding for point scales.

range : anyOf(List(float), List(string), string)

The range of the scale. One of:

A string indicating a pre-defined named scale range (e.g., example, "symbol", or "diverging" ).

For continuous scales, two-element array indicating minimum and maximum values, or an array with more than two entries for specifying a piecewise scale.

For discrete and discretizing scales, an array of desired output values.

Notes:

1) For sequential, ordinal, and discretizing color scales, you can also specify a color scheme instead of range.

2) Any directly specified range for x and y channels will be ignored. Range can be customized via the view’s corresponding size ( width and height ) or via range steps and paddings properties for band and point scales.

rangeStep : anyOf(float, None)

The distance between the starts of adjacent bands or points in band and point scales.

If rangeStep is null or if the view contains the scale’s corresponding size ( width for x scales and height for y scales), rangeStep will be automatically determined to fit the size of the view.

Default value: derived the scale config ‘s textXRangeStep ( 90 by default) for x-scales of text marks and rangeStep ( 21 by default) for x-scales of other marks and y-scales.

Warning : If rangeStep is null and the cardinality of the scale’s domain is higher than width or height, the rangeStep might become less than one pixel and the mark might not appear correctly.

round : boolean

If true, rounds numeric output values to integers. This can be helpful for snapping to the pixel grid.

Default value: false.

scheme : anyOf(string, SchemeParams)

A string indicating a color scheme name (e.g., "category10" or "viridis" ) or a scheme parameter object.

Discrete color schemes may be used with discrete or discretizing scales. Continuous color schemes are intended for use with sequential scales.

For the full list of supported schemes, please refer to the Vega Scheme reference.

type : ScaleType

The type of scale. Vega-Lite supports the following categories of scale types:

1) Continuous Scales – mapping continuous domains to continuous output ranges ( “linear”, “pow”, “sqrt”, “log”, “time”, “utc”, “sequential” ).

2) Discrete Scales – mapping discrete domains to discrete ( “ordinal” ) or continuous ( “band” and “point” ) output ranges.

3) Discretizing Scales – mapping continuous domains to discrete output ranges ( “bin-linear” and “bin-ordinal” ).

Default value: please see the scale type table.

zero : boolean

If true, ensures that a zero baseline value is included in the scale domain.

Default value: true for x and y channels if the quantitative field is not binned and no custom domain is provided; false otherwise.

Note: Log, time, and utc scales do not support zero.

class altair.ScaleConfig(bandPaddingInner=Undefined, bandPaddingOuter=Undefined, clamp=Undefined, continuousPadding=Undefined, maxBandSize=Undefined, maxFontSize=Undefined, maxOpacity=Undefined, maxSize=Undefined, maxStrokeWidth=Undefined, minBandSize=Undefined, minFontSize=Undefined, minOpacity=Undefined, minSize=Undefined, minStrokeWidth=Undefined, pointPadding=Undefined, rangeStep=Undefined, round=Undefined, textXRangeStep=Undefined, useUnaggregatedDomain=Undefined, **kwds)¶

ScaleConfig schema wrapper

Mapping(required=[])

Attributes:

bandPaddingInner : float

Default inner padding for x and y band-ordinal scales.

Default value: 0.1

bandPaddingOuter : float

Default outer padding for x and y band-ordinal scales. If not specified, by default, band scale’s paddingOuter is paddingInner/2.

clamp : boolean

If true, values that exceed the data domain are clamped to either the minimum or maximum range value

continuousPadding : float

Default padding for continuous scales.

Default: 5 for continuous x-scale of a vertical bar and continuous y-scale of a horizontal bar.; 0 otherwise.

maxBandSize : float

The default max value for mapping quantitative fields to bar’s size/bandSize.

If undefined (default), we will use the scale’s rangeStep - 1.

maxFontSize : float

The default max value for mapping quantitative fields to text’s size/fontSize.

Default value: 40

maxOpacity : float

Default max opacity for mapping a field to opacity.

Default value: 0.8

maxSize : float

Default max value for point size scale.

maxStrokeWidth : float

Default max strokeWidth for the scale of strokeWidth for rule and line marks and of size for trail marks.

Default value: 4

minBandSize : float

The default min value for mapping quantitative fields to bar and tick’s size/bandSize scale with zero=false.

Default value: 2

minFontSize : float

The default min value for mapping quantitative fields to tick’s size/fontSize scale with zero=false

Default value: 8

minOpacity : float

Default minimum opacity for mapping a field to opacity.

Default value: 0.3

minSize : float

Default minimum value for point size scale with zero=false.

Default value: 9

minStrokeWidth : float

Default minimum strokeWidth for the scale of strokeWidth for rule and line marks and of size for trail marks with zero=false.

Default value: 1

pointPadding : float

Default outer padding for x and y point-ordinal scales.

Default value: 0.5

rangeStep : anyOf(float, None)

Default range step for band and point scales of (1) the y channel and (2) the x channel when the mark is not text.

Default value: 21

round : boolean

If true, rounds numeric output values to integers. This can be helpful for snapping to the pixel grid. (Only available for x, y, and size scales.)

textXRangeStep : float

Default range step for x band and point scales of text marks.

Default value: 90

useUnaggregatedDomain : boolean

Use the source data range before aggregation as scale domain instead of aggregated data for aggregate axis.

This is equivalent to setting domain to "unaggregate" for aggregated quantitative fields by default.

This property only works with aggregate functions that produce values within the raw data domain ( "mean", "average", "median", "q1", "q3", "min", "max" ). For other aggregations that produce values outside of the raw data domain (e.g. "count", "sum" ), this property is ignored.

Default value: false

class altair.ScaleInterpolate(*args)¶

ScaleInterpolate schema wrapper

enum(‘rgb’, ‘lab’, ‘hcl’, ‘hsl’, ‘hsl-long’, ‘hcl-long’, ‘cubehelix’, ‘cubehelix-long’)

class altair.ScaleInterpolateParams(type=Undefined, gamma=Undefined, **kwds)¶

ScaleInterpolateParams schema wrapper

Mapping(required=[type])

Attributes:	type : enum(‘rgb’, ‘cubehelix’, ‘cubehelix-long’) gamma : float

class altair.ScaleResolveMap(color=Undefined, fill=Undefined, opacity=Undefined, shape=Undefined, size=Undefined, stroke=Undefined, x=Undefined, y=Undefined, **kwds)¶

ScaleResolveMap schema wrapper

Mapping(required=[])

Attributes:	color : ResolveMode fill : ResolveMode opacity : ResolveMode shape : ResolveMode size : ResolveMode stroke : ResolveMode x : ResolveMode y : ResolveMode

class altair.ScaleType(*args)¶

ScaleType schema wrapper

enum(‘linear’, ‘bin-linear’, ‘log’, ‘pow’, ‘sqrt’, ‘time’, ‘utc’, ‘sequential’, ‘ordinal’, ‘bin-ordinal’, ‘point’, ‘band’)

class altair.SchemaBase(*args, **kwds)¶

Base class for schema wrappers.

Each derived class should set the _schema class attribute (and optionally the _rootschema class attribute) which is used for validation.

copy(deep=True, ignore=())¶

Return a copy of the object

Parameters:	deep : boolean, optional if True (default) then return a deep copy of all dict, list, and SchemaBase objects within the object structure ignore : list, optional A list of keys for which the contents should not be copied, but only stored by reference.

classmethod from_dict(dct, validate=True, _wrapper_classes=None)¶

Construct class from a dictionary representation

Parameters:	dct : dictionary The dict from which to construct the class validate : boolean If True (default), then validate the input against the schema. _wrapper_classes : list (optional) The set of SchemaBase classes to use when constructing wrappers of the dict inputs. If not specified, the result of cls._default_wrapper_classes will be used.
Returns:	obj : Schema object The wrapped schema
Raises:	jsonschema.ValidationError : if validate=True and dct does not conform to the schema

classmethod from_json(json_string, validate=True, **kwargs)¶

Instantiate the object from a valid JSON string

Parameters:	json_string : string The string containing a valid JSON chart specification. validate : boolean If True (default), then validate the input against the schema. **kwargs : Additional keyword arguments are passed to json.loads
Returns:	chart : Chart object The altair Chart object built from the specification.

classmethod resolve_references(schema)¶: Resolve references of the schema the context of this object’s schema

to_dict(validate=True, ignore=[], context={})¶

Return a dictionary representation of the object

Parameters:	validate : boolean or string If True (default), then validate the output dictionary against the schema. If “deep” then recursively validate all objects in the spec. This takes much more time, but it results in friendlier tracebacks for large objects. ignore : list A list of keys to ignore. This will not passed to child to_dict function calls. context : dict (optional) A context dictionary that will be passed to all child to_dict function calls
Returns:	dct : dictionary The dictionary representation of this object
Raises:	jsonschema.ValidationError : if validate=True and the dict does not conform to the schema

to_json(validate=True, ignore=[], context={}, indent=2, sort_keys=True, **kwargs)¶

Emit the JSON representation for this object as a string.

Parameters:

validate : boolean or string: If True (default), then validate the output dictionary against the schema. If “deep” then recursively validate all objects in the spec. This takes much more time, but it results in friendlier tracebacks for large objects.
ignore : list: A list of keys to ignore. This will not passed to child to_dict function calls.
context : dict (optional): A context dictionary that will be passed to all child to_dict function calls
indent : integer, default 2: the number of spaces of indentation to use
sort_keys : boolean, default True: if True, sort keys in the output
**kwargs: Additional keyword arguments are passed to json.dumps()

Returns:

spec : string: The JSON specification of the chart object.

classmethod validate(instance, schema=None)¶: Validate the instance against the class schema in the context of the rootschema.

class altair.SchemeParams(name=Undefined, extent=Undefined, **kwds)¶

SchemeParams schema wrapper

Mapping(required=[name])

Attributes:

name : string

A color scheme name for sequential/ordinal scales (e.g., "category10" or "viridis" ).

For the full list of supported schemes, please refer to the Vega Scheme reference.

extent : List(float)

For sequential and diverging schemes only, determines the extent of the color range to use. For example [0.2, 1] will rescale the color scheme such that color values in the range [0, 0.2) are excluded from the scheme.

class altair.SelectionAnd(**kwds)¶

SelectionAnd schema wrapper

Mapping(required=[and])

Attributes:	and : List(SelectionOperand)

class altair.SelectionConfig(interval=Undefined, multi=Undefined, single=Undefined, **kwds)¶

SelectionConfig schema wrapper

Mapping(required=[])

Attributes:

interval : IntervalSelectionConfig

The default definition for an interval selection. All properties and transformations for an interval selection definition (except type ) may be specified here.

For instance, setting interval to {"translate": false} disables the ability to move interval selections by default.

multi : MultiSelectionConfig

The default definition for a multi selection. All properties and transformations for a multi selection definition (except type ) may be specified here.

For instance, setting multi to {"toggle": "event.altKey"} adds additional values to multi selections when clicking with the alt-key pressed by default.

single : SingleSelectionConfig

The default definition for a single selection. All properties and transformations for a single selection definition (except type ) may be specified here.

For instance, setting single to {"on": "dblclick"} populates single selections on double-click by default.

class altair.SelectionDef(*args, **kwds)¶

SelectionDef schema wrapper

anyOf(SingleSelection, MultiSelection, IntervalSelection)

class altair.SelectionDomain(*args, **kwds)¶

SelectionDomain schema wrapper

anyOf(Mapping(required=[selection]), Mapping(required=[selection]))

class altair.SelectionMapping(*args, **kwds)¶

A mapping of selection names to selection definitions.

This is designed to match the schema of the “selection” property of top-level objects.

class altair.SelectionNot(**kwds)¶

SelectionNot schema wrapper

Mapping(required=[not])

Attributes:	not : SelectionOperand

class altair.SelectionOperand(*args, **kwds)¶

SelectionOperand schema wrapper

anyOf(SelectionNot, SelectionAnd, SelectionOr, string)

class altair.SelectionOr(**kwds)¶

SelectionOr schema wrapper

Mapping(required=[or])

Attributes:	or : List(SelectionOperand)

class altair.SelectionPredicate(selection=Undefined, **kwds)¶

SelectionPredicate schema wrapper

Mapping(required=[selection])

Attributes:	selection : SelectionOperand Filter using a selection name.

class altair.SelectionResolution(*args)¶

SelectionResolution schema wrapper

enum(‘global’, ‘union’, ‘intersect’)

class altair.Shape(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, legend=Undefined, scale=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

Shape schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

legend : anyOf(Legend, None)

An object defining properties of the legend. If null, the legend for the encoding channel will be removed.

Default value: If undefined, default legend properties are applied.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.ShapeValue(value, condition=Undefined, **kwds)

ShapeValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalMarkPropFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.SingleDefChannel(*args)¶

SingleDefChannel schema wrapper

enum(‘x’, ‘y’, ‘x2’, ‘y2’, ‘longitude’, ‘latitude’, ‘longitude2’, ‘latitude2’, ‘row’, ‘column’, ‘color’, ‘fill’, ‘stroke’, ‘size’, ‘shape’, ‘opacity’, ‘text’, ‘tooltip’, ‘href’, ‘key’)

class altair.SingleSelection(type=Undefined, bind=Undefined, empty=Undefined, encodings=Undefined, fields=Undefined, nearest=Undefined, on=Undefined, resolve=Undefined, **kwds)¶

SingleSelection schema wrapper

Mapping(required=[type])

Attributes:

type : enum(‘single’)

bind : anyOf(VgBinding, Mapping(required=[]))

Establish a two-way binding between a single selection and input elements (also known as dynamic query widgets). A binding takes the form of Vega’s input element binding definition or can be a mapping between projected field/encodings and binding definitions.

See the bind transform documentation for more information.

empty : enum(‘all’, ‘none’)

By default, all data values are considered to lie within an empty selection. When set to none, empty selections contain no data values.

encodings : List(SingleDefChannel)

An array of encoding channels. The corresponding data field values must match for a data tuple to fall within the selection.

fields : List(string)

An array of field names whose values must match for a data tuple to fall within the selection.

nearest : boolean

When true, an invisible voronoi diagram is computed to accelerate discrete selection. The data value nearest the mouse cursor is added to the selection.

See the nearest transform documentation for more information.

on : VgEventStream

A Vega event stream (object or selector) that triggers the selection. For interval selections, the event stream must specify a start and end.

resolve : SelectionResolution

With layered and multi-view displays, a strategy that determines how selections’ data queries are resolved when applied in a filter transform, conditional encoding rule, or scale domain.

class altair.SingleSelectionConfig(bind=Undefined, empty=Undefined, encodings=Undefined, fields=Undefined, nearest=Undefined, on=Undefined, resolve=Undefined, **kwds)¶

SingleSelectionConfig schema wrapper

Mapping(required=[])

Attributes:

bind : anyOf(VgBinding, Mapping(required=[]))

Establish a two-way binding between a single selection and input elements (also known as dynamic query widgets). A binding takes the form of Vega’s input element binding definition or can be a mapping between projected field/encodings and binding definitions.

See the bind transform documentation for more information.

empty : enum(‘all’, ‘none’)

By default, all data values are considered to lie within an empty selection. When set to none, empty selections contain no data values.

encodings : List(SingleDefChannel)

An array of encoding channels. The corresponding data field values must match for a data tuple to fall within the selection.

fields : List(string)

An array of field names whose values must match for a data tuple to fall within the selection.

nearest : boolean

When true, an invisible voronoi diagram is computed to accelerate discrete selection. The data value nearest the mouse cursor is added to the selection.

See the nearest transform documentation for more information.

on : VgEventStream

A Vega event stream (object or selector) that triggers the selection. For interval selections, the event stream must specify a start and end.

resolve : SelectionResolution

With layered and multi-view displays, a strategy that determines how selections’ data queries are resolved when applied in a filter transform, conditional encoding rule, or scale domain.

class altair.SingleTimeUnit(*args, **kwds)¶

SingleTimeUnit schema wrapper

anyOf(LocalSingleTimeUnit, UtcSingleTimeUnit)

class altair.Size(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, legend=Undefined, scale=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

Size schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

legend : anyOf(Legend, None)

An object defining properties of the legend. If null, the legend for the encoding channel will be removed.

Default value: If undefined, default legend properties are applied.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.SizeValue(value, condition=Undefined, **kwds)

SizeValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalMarkPropFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.Sort(*args, **kwds)¶

Sort schema wrapper

anyOf(List(float), List(string), List(boolean), List(DateTime), SortOrder, EncodingSortField, None)

class altair.SortField(field=Undefined, order=Undefined, **kwds)¶

SortField schema wrapper

Mapping(required=[field]) A sort definition for transform

Attributes:	field : string The name of the field to sort. order : VgComparatorOrder Whether to sort the field in ascending or descending order.

class altair.SortOrder(*args, **kwds)¶

SortOrder schema wrapper

anyOf(VgComparatorOrder, None)

class altair.Spec(*args, **kwds)¶

Spec schema wrapper

anyOf(CompositeUnitSpec, LayerSpec, FacetSpec, RepeatSpec, VConcatSpec, HConcatSpec)

class altair.StackOffset(*args)¶

StackOffset schema wrapper

enum(‘zero’, ‘center’, ‘normalize’)

class altair.Stroke(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, legend=Undefined, scale=Undefined, sort=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)¶

Stroke schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

legend : anyOf(Legend, None)

An object defining properties of the legend. If null, the legend for the encoding channel will be removed.

Default value: If undefined, default legend properties are applied.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.StrokeCap(*args)¶

StrokeCap schema wrapper

enum(‘butt’, ‘round’, ‘square’)

class altair.StrokeJoin(*args)¶

StrokeJoin schema wrapper

enum(‘miter’, ‘round’, ‘bevel’)

class altair.StrokeValue(value, condition=Undefined, **kwds)¶

StrokeValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalMarkPropFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.StyleConfigIndex(**kwds)¶

StyleConfigIndex schema wrapper

Mapping(required=[])

class altair.Text(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, format=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

Text schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

format : string

The formatting pattern for a text field. If not defined, this will be determined automatically.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.TextBaseline(*args, **kwds)¶

TextBaseline schema wrapper

anyOf(enum(‘alphabetic’), Baseline)

class altair.TextConfig(align=Undefined, angle=Undefined, baseline=Undefined, color=Undefined, cornerRadius=Undefined, cursor=Undefined, dir=Undefined, dx=Undefined, dy=Undefined, ellipsis=Undefined, fill=Undefined, fillOpacity=Undefined, filled=Undefined, font=Undefined, fontSize=Undefined, fontStyle=Undefined, fontWeight=Undefined, href=Undefined, interpolate=Undefined, limit=Undefined, opacity=Undefined, orient=Undefined, radius=Undefined, shape=Undefined, shortTimeLabels=Undefined, size=Undefined, stroke=Undefined, strokeCap=Undefined, strokeDash=Undefined, strokeDashOffset=Undefined, strokeJoin=Undefined, strokeMiterLimit=Undefined, strokeOpacity=Undefined, strokeWidth=Undefined, tension=Undefined, text=Undefined, theta=Undefined, tooltip=Undefined, **kwds)¶

TextConfig schema wrapper

Mapping(required=[])

Attributes:

align : HorizontalAlign

The horizontal alignment of the text. One of "left", "right", "center".

angle : float

The rotation angle of the text, in degrees.

baseline : VerticalAlign

The vertical alignment of the text. One of "top", "middle", "bottom".

Default value: "middle"

color : string

Default color. Note that fill and stroke have higher precedence than color and will override color.

Default value: ■ "#4682b4"

Note: This property cannot be used in a style config.

cornerRadius : float

The radius in pixels of rounded rectangle corners. Default value: 0

cursor : Cursor

The mouse cursor used over the mark. Any valid CSS cursor type can be used.

dir : Dir

The direction of the text. One of "ltr" (left-to-right) or "rtl" (right-to-left). This property determines on which side is truncated in response to the limit parameter. Default value: "ltr"

dx : float

The horizontal offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

dy : float

The vertical offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

ellipsis : string

The ellipsis string for text truncated in response to the limit parameter. Default value: "…"

fill : string

Default Fill Color. This has higher precedence than config.color

Default value: (None)

fillOpacity : float

The fill opacity (value between [0,1]).

Default value: 1

filled : boolean

Whether the mark’s color should be used as fill color instead of stroke color.

Default value: true for all marks except point and false for point.

Applicable for: bar, point, circle, square, and area marks.

Note: This property cannot be used in a style config.

font : string

The typeface to set the text in (e.g., "Helvetica Neue" ).

fontSize : float

The font size, in pixels.

fontStyle : FontStyle

The font style (e.g., "italic" ).

fontWeight : FontWeight

The font weight. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

href : string

A URL to load upon mouse click. If defined, the mark acts as a hyperlink.

interpolate : Interpolate

The line interpolation method to use for line and area marks. One of the following:

"linear" : piecewise linear segments, as in a polyline.
"linear-closed" : close the linear segments to form a polygon.
"step" : alternate between horizontal and vertical segments, as in a step function.
"step-before" : alternate between vertical and horizontal segments, as in a step function.
"step-after" : alternate between horizontal and vertical segments, as in a step function.
"basis" : a B-spline, with control point duplication on the ends.
"basis-open" : an open B-spline; may not intersect the start or end.
"basis-closed" : a closed B-spline, as in a loop.
"cardinal" : a Cardinal spline, with control point duplication on the ends.
"cardinal-open" : an open Cardinal spline; may not intersect the start or end, but will intersect other control points.
"cardinal-closed" : a closed Cardinal spline, as in a loop.
"bundle" : equivalent to basis, except the tension parameter is used to straighten the spline.
"monotone" : cubic interpolation that preserves monotonicity in y.

limit : float

The maximum length of the text mark in pixels. The text value will be automatically truncated if the rendered size exceeds the limit. Default value: 0, indicating no limit

opacity : float

The overall opacity (value between [0,1]).

Default value: 0.7 for non-aggregate plots with point, tick, circle, or square marks or layered bar charts and 1 otherwise.

orient : Orient

The orientation of a non-stacked bar, tick, area, and line charts. The value is either horizontal (default) or vertical.

For bar, rule and tick, this determines whether the size of the bar and tick

should be applied to x or y dimension. * For area, this property determines the orient property of the Vega output. * For line and trail marks, this property determines the sort order of the points in

the line

if config.sortLineBy is not specified. For stacked charts, this is always determined by the orientation of the stack; therefore explicitly specified value will be ignored.

radius : float

Polar coordinate radial offset, in pixels, of the text label from the origin determined by the x and y properties.

shape : string

The default symbol shape to use. One of: "circle" (default), "square", "cross", "diamond", "triangle-up", or "triangle-down", or a custom SVG path.

Default value: "circle"

shortTimeLabels : boolean

Whether month names and weekday names should be abbreviated.

size : float

The pixel area each the point/circle/square. For example: in the case of circles, the radius is determined in part by the square root of the size value.

Default value: 30

stroke : string

<<<<<<< HEAD

Default Stroke Color. This has higher precedence than config.color

Default value: (None)

strokeCap : enum(‘butt’, ‘round’, ‘square’)

=======

Default Stroke Color. This has higher precedence than config.color Default value: (None)

strokeCap : StrokeCap

>>>>>>> altair-viz/master

The stroke cap for line ending style. One of "butt", "round", or "square".

Default value: "square"

strokeDash : List(float)

An array of alternating stroke, space lengths for creating dashed or dotted lines.

strokeDashOffset : float

The offset (in pixels) into which to begin drawing with the stroke dash array.

strokeJoin : StrokeJoin

The stroke line join method. One of "miter", "round" or "bevel". Default value: "miter"

strokeMiterLimit : float

The miter limit at which to bevel a line join.

strokeOpacity : float

The stroke opacity (value between [0,1]).

Default value: 1

strokeWidth : float

The stroke width, in pixels.

tension : float

Depending on the interpolation type, sets the tension parameter (for line and area marks).

text : string

Placeholder text if the text channel is not specified

theta : float

Polar coordinate angle, in radians, of the text label from the origin determined by the x and y properties. Values for theta follow the same convention of arc mark startAngle and endAngle properties: angles are measured in radians, with 0 indicating “north”.

tooltip : Mapping(required=[])

The tooltip text to show upon mouse hover.

class altair.TextFieldDef(type=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, format=Undefined, timeUnit=Undefined, title=Undefined, **kwds)¶

TextFieldDef schema wrapper

Mapping(required=[type])

Attributes:

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

format : string

The formatting pattern for a text field. If not defined, this will be determined automatically.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

class altair.TextFieldDefWithCondition(type=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, format=Undefined, timeUnit=Undefined, title=Undefined, **kwds)¶

TextFieldDefWithCondition schema wrapper

Mapping(required=[type]) A FieldDef with Condition

Attributes:

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

format : string

The formatting pattern for a text field. If not defined, this will be determined automatically.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

class altair.TextValue(value, condition=Undefined, **kwds)

TextValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalTextFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.TextValueDefWithCondition(condition=Undefined, value=Undefined, **kwds)¶

TextValueDefWithCondition schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalTextFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.TickConfig(align=Undefined, angle=Undefined, bandSize=Undefined, baseline=Undefined, color=Undefined, cornerRadius=Undefined, cursor=Undefined, dir=Undefined, dx=Undefined, dy=Undefined, ellipsis=Undefined, fill=Undefined, fillOpacity=Undefined, filled=Undefined, font=Undefined, fontSize=Undefined, fontStyle=Undefined, fontWeight=Undefined, href=Undefined, interpolate=Undefined, limit=Undefined, opacity=Undefined, orient=Undefined, radius=Undefined, shape=Undefined, size=Undefined, stroke=Undefined, strokeCap=Undefined, strokeDash=Undefined, strokeDashOffset=Undefined, strokeJoin=Undefined, strokeMiterLimit=Undefined, strokeOpacity=Undefined, strokeWidth=Undefined, tension=Undefined, text=Undefined, theta=Undefined, thickness=Undefined, tooltip=Undefined, **kwds)¶

TickConfig schema wrapper

Mapping(required=[])

Attributes:

align : HorizontalAlign

The horizontal alignment of the text. One of "left", "right", "center".

angle : float

The rotation angle of the text, in degrees.

bandSize : float

The width of the ticks.

Default value: 2/3 of rangeStep.

baseline : VerticalAlign

The vertical alignment of the text. One of "top", "middle", "bottom".

Default value: "middle"

color : string

Default color. Note that fill and stroke have higher precedence than color and will override color.

Default value: ■ "#4682b4"

Note: This property cannot be used in a style config.

cornerRadius : float

The radius in pixels of rounded rectangle corners. Default value: 0

cursor : Cursor

The mouse cursor used over the mark. Any valid CSS cursor type can be used.

dir : Dir

The direction of the text. One of "ltr" (left-to-right) or "rtl" (right-to-left). This property determines on which side is truncated in response to the limit parameter. Default value: "ltr"

dx : float

The horizontal offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

dy : float

The vertical offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

ellipsis : string

The ellipsis string for text truncated in response to the limit parameter. Default value: "…"

fill : string

Default Fill Color. This has higher precedence than config.color

Default value: (None)

fillOpacity : float

The fill opacity (value between [0,1]).

Default value: 1

filled : boolean

Whether the mark’s color should be used as fill color instead of stroke color.

Default value: true for all marks except point and false for point.

Applicable for: bar, point, circle, square, and area marks.

Note: This property cannot be used in a style config.

font : string

The typeface to set the text in (e.g., "Helvetica Neue" ).

fontSize : float

The font size, in pixels.

fontStyle : FontStyle

The font style (e.g., "italic" ).

fontWeight : FontWeight

The font weight. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

href : string

A URL to load upon mouse click. If defined, the mark acts as a hyperlink.

interpolate : Interpolate

The line interpolation method to use for line and area marks. One of the following:

"linear" : piecewise linear segments, as in a polyline.
"linear-closed" : close the linear segments to form a polygon.
"step" : alternate between horizontal and vertical segments, as in a step function.
"step-before" : alternate between vertical and horizontal segments, as in a step function.
"step-after" : alternate between horizontal and vertical segments, as in a step function.
"basis" : a B-spline, with control point duplication on the ends.
"basis-open" : an open B-spline; may not intersect the start or end.
"basis-closed" : a closed B-spline, as in a loop.
"cardinal" : a Cardinal spline, with control point duplication on the ends.
"cardinal-open" : an open Cardinal spline; may not intersect the start or end, but will intersect other control points.
"cardinal-closed" : a closed Cardinal spline, as in a loop.
"bundle" : equivalent to basis, except the tension parameter is used to straighten the spline.
"monotone" : cubic interpolation that preserves monotonicity in y.

limit : float

The maximum length of the text mark in pixels. The text value will be automatically truncated if the rendered size exceeds the limit. Default value: 0, indicating no limit

opacity : float

The overall opacity (value between [0,1]).

Default value: 0.7 for non-aggregate plots with point, tick, circle, or square marks or layered bar charts and 1 otherwise.

orient : Orient

The orientation of a non-stacked bar, tick, area, and line charts. The value is either horizontal (default) or vertical.

For bar, rule and tick, this determines whether the size of the bar and tick

should be applied to x or y dimension. * For area, this property determines the orient property of the Vega output. * For line and trail marks, this property determines the sort order of the points in

the line

if config.sortLineBy is not specified. For stacked charts, this is always determined by the orientation of the stack; therefore explicitly specified value will be ignored.

radius : float

Polar coordinate radial offset, in pixels, of the text label from the origin determined by the x and y properties.

shape : string

The default symbol shape to use. One of: "circle" (default), "square", "cross", "diamond", "triangle-up", or "triangle-down", or a custom SVG path.

Default value: "circle"

size : float

The pixel area each the point/circle/square. For example: in the case of circles, the radius is determined in part by the square root of the size value.

Default value: 30

stroke : string

<<<<<<< HEAD

Default Stroke Color. This has higher precedence than config.color

Default value: (None)

strokeCap : enum(‘butt’, ‘round’, ‘square’)

=======

Default Stroke Color. This has higher precedence than config.color Default value: (None)

strokeCap : StrokeCap

>>>>>>> altair-viz/master

The stroke cap for line ending style. One of "butt", "round", or "square".

Default value: "square"

strokeDash : List(float)

An array of alternating stroke, space lengths for creating dashed or dotted lines.

strokeDashOffset : float

The offset (in pixels) into which to begin drawing with the stroke dash array.

strokeJoin : StrokeJoin

The stroke line join method. One of "miter", "round" or "bevel". Default value: "miter"

strokeMiterLimit : float

The miter limit at which to bevel a line join.

strokeOpacity : float

The stroke opacity (value between [0,1]).

Default value: 1

strokeWidth : float

The stroke width, in pixels.

tension : float

Depending on the interpolation type, sets the tension parameter (for line and area marks).

text : string

Placeholder text if the text channel is not specified

theta : float

Polar coordinate angle, in radians, of the text label from the origin determined by the x and y properties. Values for theta follow the same convention of arc mark startAngle and endAngle properties: angles are measured in radians, with 0 indicating “north”.

thickness : float

<<<<<<< HEAD

Thickness of the tick mark.

Default value: 1

=======

Thickness of the tick mark. Default value: 1

tooltip : Mapping(required=[]): The tooltip text to show upon mouse hover.

>>>>>>> altair-viz/master

class altair.TimeUnit(*args, **kwds)¶

TimeUnit schema wrapper

anyOf(SingleTimeUnit, MultiTimeUnit)

class altair.TimeUnitTransform(field=Undefined, timeUnit=Undefined, **kwds)¶

TimeUnitTransform schema wrapper

Mapping(required=[timeUnit, field, as])

Attributes:	field : string The data field to apply time unit. timeUnit : TimeUnit The timeUnit. as : string The output field to write the timeUnit value.

class altair.TitleOrient(*args)¶

TitleOrient schema wrapper

enum(‘top’, ‘bottom’, ‘left’, ‘right’)

class altair.TitleParams(text=Undefined, anchor=Undefined, offset=Undefined, orient=Undefined, style=Undefined, **kwds)¶

TitleParams schema wrapper

Mapping(required=[text])

Attributes:

text : string

The title text.

anchor : Anchor

The anchor position for placing the title. One of "start", "middle", or "end". For example, with an orientation of top these anchor positions map to a left-, center-, or right-aligned title.

Default value: "middle" for single and layered views. "start" for other composite views.

Note: For now, anchor is only customizable only for single and layered views. For other composite views, anchor is always "start".

offset : float

The orthogonal offset in pixels by which to displace the title from its position along the edge of the chart.

orient : TitleOrient

The orientation of the title relative to the chart. One of "top" (the default), "bottom", "left", or "right".

style : anyOf(string, List(string))

A mark style property to apply to the title text mark.

Default value: "group-title".

class altair.Tooltip(shorthand=Undefined, aggregate=Undefined, bin=Undefined, condition=Undefined, field=Undefined, format=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

Tooltip schema wrapper

Mapping(required=[shorthand]) A FieldDef with Condition

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

condition : anyOf(ConditionalValueDef, List(ConditionalValueDef))

One or more value definition(s) with a selection predicate.

Note: A field definition’s condition property can only contain value definitions since Vega-Lite only allows at most one encoded field per encoding channel.

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

format : string

The formatting pattern for a text field. If not defined, this will be determined automatically.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.TooltipValue(value, condition=Undefined, **kwds)

TooltipValue schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalTextFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.TopLevelFacetSpec(data=Undefined, facet=Undefined, spec=Undefined, align=Undefined, autosize=Undefined, background=Undefined, bounds=Undefined, center=Undefined, config=Undefined, datasets=Undefined, description=Undefined, name=Undefined, padding=Undefined, resolve=Undefined, spacing=Undefined, title=Undefined, transform=Undefined, **kwds)¶

TopLevelFacetSpec schema wrapper

Mapping(required=[data, facet, spec])

Attributes:

data : Data

An object describing the data source

facet : FacetMapping

An object that describes mappings between row and column channels and their field definitions.

spec : anyOf(LayerSpec, CompositeUnitSpec)

A specification of the view that gets faceted.

align : anyOf(VgLayoutAlign, RowColVgLayoutAlign)

The alignment to apply to grid rows and columns. The supported string values are "all", "each", and "none". * For "none", a flow layout will be used, in which adjacent subviews are simply placed one after the other. * For "each", subviews will be aligned into a clean grid structure, but each row or column may be of variable size. * For "all", subviews will be aligned and each row or column will be sized identically based on the maximum observed size. String values for this property will be applied to both grid rows and columns. Alternatively, an object value of the form {"row": string, "column": string} can

be used to supply different alignments for rows and columns. Default value:

"all".

autosize : anyOf(AutosizeType, AutoSizeParams)

Sets how the visualization size should be determined. If a string, should be one of "pad", "fit" or "none". Object values can additionally specify parameters for content sizing and automatic resizing. "fit" is only supported for single and layered views that don’t use rangeStep.

Default value : pad

background : string

<<<<<<< HEAD

CSS color property to use as the background of visualization.

Default value: none (transparent)

=======

CSS color property to use as the background of visualization. Default value: none (transparent)

bounds : enum(‘full’, ‘flush’): The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"
center : anyOf(boolean, RowColboolean): Boolean flag indicating if subviews should be centered relative to their respective rows or columns. An object value of the form {"row": boolean, "column": boolean} can be used to supply different centering values for rows and columns. Default value: false

>>>>>>> altair-viz/master

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

resolve : Resolve

Scale, axis, and legend resolutions for facets.

spacing : anyOf(float, RowColnumber)

The spacing in pixels between sub-views of the composition operator. An object of the form {"row": number, "column": number} can be used to set different spacing values for rows and columns. Default value : 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

$schema : string

URL to JSON schema for a Vega-Lite specification. Unless you have a reason to change this, use https://vega.github.io/schema/vega-lite/v2.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

class altair.TopLevelFacetedUnitSpec(data=Undefined, mark=Undefined, autosize=Undefined, background=Undefined, config=Undefined, datasets=Undefined, description=Undefined, encoding=Undefined, height=Undefined, name=Undefined, padding=Undefined, projection=Undefined, selection=Undefined, title=Undefined, transform=Undefined, width=Undefined, **kwds)¶

TopLevelFacetedUnitSpec schema wrapper

Mapping(required=[data, mark])

Attributes:

data : Data

An object describing the data source

mark : AnyMark

A string describing the mark type (one of "bar", "circle", "square", "tick", "line", "area", "point", "rule", "geoshape", and "text" ) or a mark definition object.

autosize : anyOf(AutosizeType, AutoSizeParams)

Sets how the visualization size should be determined. If a string, should be one of "pad", "fit" or "none". Object values can additionally specify parameters for content sizing and automatic resizing. "fit" is only supported for single and layered views that don’t use rangeStep.

Default value : pad

background : string

CSS color property to use as the background of visualization.

Default value: none (transparent)

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

description : string

Description of this mark for commenting purpose.

encoding : EncodingWithFacet

A key-value mapping between encoding channels and definition of fields.

height : float

The height of a visualization.

Default value:

If a view’s autosize type is "fit" or its y-channel has a continuous scale, the height will be the value of config.view.height.
For y-axis with a band or point scale: if rangeStep is a numeric value or unspecified, the height is determined by the range step, paddings, and the cardinality of the field mapped to y-channel. Otherwise, if the rangeStep is null, the height will be the value of config.view.height.
If no field is mapped to y channel, the height will be the value of rangeStep.

Note : For plots with row and column channels, this represents the height of a single view.

See also: The documentation for width and height contains more examples.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

projection : Projection

An object defining properties of geographic projection, which will be applied to shape path for "geoshape" marks and to latitude and "longitude" channels for other marks.

selection : Mapping(required=[])

A key-value mapping between selection names and definitions.

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

width : float

The width of a visualization.

Default value: This will be determined by the following rules:

If a view’s autosize type is "fit" or its x-channel has a continuous scale, the width will be the value of config.view.width.
For x-axis with a band or point scale: if rangeStep is a numeric value or unspecified, the width is determined by the range step, paddings, and the cardinality of the field mapped to x-channel. Otherwise, if the rangeStep is null, the width will be the value of config.view.width.
If no field is mapped to x channel, the width will be the value of config.scale.textXRangeStep for text mark and the value of rangeStep for other marks.

Note: For plots with row and column channels, this represents the width of a single view.

See also: The documentation for width and height contains more examples.

$schema : string

URL to JSON schema for a Vega-Lite specification. Unless you have a reason to change this, use https://vega.github.io/schema/vega-lite/v2.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

class altair.TopLevelHConcatSpec(hconcat=Undefined, autosize=Undefined, background=Undefined, bounds=Undefined, center=Undefined, config=Undefined, data=Undefined, datasets=Undefined, description=Undefined, name=Undefined, padding=Undefined, resolve=Undefined, spacing=Undefined, title=Undefined, transform=Undefined, **kwds)¶

TopLevelHConcatSpec schema wrapper

Mapping(required=[hconcat])

Attributes:

hconcat : List(Spec)

A list of views that should be concatenated and put into a row.

autosize : anyOf(AutosizeType, AutoSizeParams)

Sets how the visualization size should be determined. If a string, should be one of "pad", "fit" or "none". Object values can additionally specify parameters for content sizing and automatic resizing. "fit" is only supported for single and layered views that don’t use rangeStep.

Default value : pad

background : string

<<<<<<< HEAD

CSS color property to use as the background of visualization.

Default value: none (transparent)

=======

CSS color property to use as the background of visualization. Default value: none (transparent)

bounds : enum(‘full’, ‘flush’): The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"
center : boolean: Boolean flag indicating if subviews should be centered relative to their respective rows or columns. Default value: false

>>>>>>> altair-viz/master

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

data : Data

An object describing the data source

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

resolve : Resolve

Scale, axis, and legend resolutions for horizontally concatenated charts.

spacing : float

The spacing in pixels between sub-views of the concat operator. Default value :: 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

$schema : string

URL to JSON schema for a Vega-Lite specification. Unless you have a reason to change this, use https://vega.github.io/schema/vega-lite/v2.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

class altair.TopLevelLayerSpec(layer=Undefined, autosize=Undefined, background=Undefined, config=Undefined, data=Undefined, datasets=Undefined, description=Undefined, encoding=Undefined, height=Undefined, name=Undefined, padding=Undefined, projection=Undefined, resolve=Undefined, title=Undefined, transform=Undefined, width=Undefined, **kwds)¶

TopLevelLayerSpec schema wrapper

Mapping(required=[layer])

Attributes:

layer : List(anyOf(LayerSpec, CompositeUnitSpec))

Layer or single view specifications to be layered.

Note : Specifications inside layer cannot use row and column channels as layering facet specifications is not allowed.

autosize : anyOf(AutosizeType, AutoSizeParams)

Sets how the visualization size should be determined. If a string, should be one of "pad", "fit" or "none". Object values can additionally specify parameters for content sizing and automatic resizing. "fit" is only supported for single and layered views that don’t use rangeStep.

Default value : pad

background : string

CSS color property to use as the background of visualization.

Default value: none (transparent)

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

data : Data

An object describing the data source

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

description : string

Description of this mark for commenting purpose.

encoding : Encoding

A shared key-value mapping between encoding channels and definition of fields in the underlying layers.

height : float

The height of a visualization.

Default value:

If a view’s autosize type is "fit" or its y-channel has a continuous scale, the height will be the value of config.view.height.
For y-axis with a band or point scale: if rangeStep is a numeric value or unspecified, the height is determined by the range step, paddings, and the cardinality of the field mapped to y-channel. Otherwise, if the rangeStep is null, the height will be the value of config.view.height.
If no field is mapped to y channel, the height will be the value of rangeStep.

Note : For plots with row and column channels, this represents the height of a single view.

See also: The documentation for width and height contains more examples.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

projection : Projection

An object defining properties of the geographic projection shared by underlying layers.

resolve : Resolve

Scale, axis, and legend resolutions for layers.

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

width : float

The width of a visualization.

Default value: This will be determined by the following rules:

If a view’s autosize type is "fit" or its x-channel has a continuous scale, the width will be the value of config.view.width.
For x-axis with a band or point scale: if rangeStep is a numeric value or unspecified, the width is determined by the range step, paddings, and the cardinality of the field mapped to x-channel. Otherwise, if the rangeStep is null, the width will be the value of config.view.width.
If no field is mapped to x channel, the width will be the value of config.scale.textXRangeStep for text mark and the value of rangeStep for other marks.

Note: For plots with row and column channels, this represents the width of a single view.

See also: The documentation for width and height contains more examples.

$schema : string

URL to JSON schema for a Vega-Lite specification. Unless you have a reason to change this, use https://vega.github.io/schema/vega-lite/v2.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

class altair.TopLevelMixin¶

Mixin for top-level chart objects such as Chart, LayeredChart, etc.

add_selection(*selections)¶: Add one or more selections to the chart

display(renderer=Undefined, theme=Undefined, actions=Undefined, **kwargs)¶

Display chart in Jupyter notebook or JupyterLab

Parameters are passed as options to vega-embed within supported frontends. See https://github.com/vega/vega-embed#options for details.

Parameters:	renderer : string (‘canvas’ or ‘svg’) The renderer to use theme : string The Vega theme name to use; see https://github.com/vega/vega-themes actions : bool or dict Specify whether action links (“Open In Vega Editor”, etc.) are included in the view. **kwargs : Additional parameters are also passed to vega-embed as options.

project(type='mercator', center=Undefined, clipAngle=Undefined, clipExtent=Undefined, coefficient=Undefined, distance=Undefined, fraction=Undefined, lobes=Undefined, parallel=Undefined, precision=Undefined, radius=Undefined, ratio=Undefined, rotate=Undefined, spacing=Undefined, tilt=Undefined, **kwds)¶

Add a geographic projection to the chartself.

This is generally used either with mark_geoshape or with the latitude/longitude encodings.

Available projection types are [‘albers’, ‘albersUsa’, ‘azimuthalEqualArea’, ‘azimuthalEquidistant’,

‘conicConformal’, ‘conicEqualArea’, ‘conicEquidistant’, ‘equirectangular’, ‘gnomonic’, ‘mercator’, ‘orthographic’, ‘stereographic’, ‘transverseMercator’]

Attributes:

type : ProjectionType

The cartographic projection to use. This value is case-insensitive, for example “albers” and “Albers” indicate the same projection type. You can find all valid projection types [in the documentation](https://vega.github.io/vega-lite/docs/projection.html#projection-types).

Default value: mercator

center : List(float)

Sets the projection’s center to the specified center, a two-element array of longitude and latitude in degrees.

Default value: [0, 0]

clipAngle : float

Sets the projection’s clipping circle radius to the specified angle in degrees. If null, switches to [antimeridian](http://bl.ocks.org/mbostock/3788999) cutting rather than small-circle clipping.

clipExtent : List(List(float))

Sets the projection’s viewport clip extent to the specified bounds in pixels. The extent bounds are specified as an array [[x0, y0], [x1, y1]], where x0 is the left-side of the viewport, y0 is the top, x1 is the right and y1 is the bottom. If null, no viewport clipping is performed.

coefficient : float

distance : float

fraction : float

lobes : float

parallel : float

precision : Mapping(required=[length])

Sets the threshold for the projection’s [adaptive resampling](http://bl.ocks.org/mbostock/3795544) to the specified value in pixels. This value corresponds to the [Douglas–Peucker distance](http://en.wikipedia.org/wiki/Ramer%E2%80%93Douglas%E2%80%93Peucker_algorithm).

If precision is not specified, returns the projection’s current resampling

precision which defaults to √0.5 ≅ 0.70710….

radius : float

ratio : float

rotate : List(float)

Sets the projection’s three-axis rotation to the specified angles, which must be a two- or three-element array of numbers [lambda, phi, gamma] specifying the rotation angles in degrees about each spherical axis. (These correspond to yaw, pitch and roll.)

Default value: [0, 0, 0]

spacing : float

tilt : float

properties(**kwargs)¶

Set top-level properties of the Chart.

Argument names and types are the same as class initialization.

repeat(row=Undefined, column=Undefined, **kwargs)¶

Return a RepeatChart built from the chart

Fields within the chart can be set to correspond to the row or column using alt.repeat(‘row’) and alt.repeat(‘column’).

Parameters:	row : list a list of data column names to be mapped to the row facet column : list a list of data column names to be mapped to the column facet
Returns:	chart : RepeatChart a repeated chart.

resolve_axis(x=Undefined, y=Undefined, **kwds)¶

AxisResolveMap schema wrapper

Mapping(required=[])

Attributes:	x : ResolveMode y : ResolveMode

resolve_legend(color=Undefined, fill=Undefined, opacity=Undefined, shape=Undefined, size=Undefined, stroke=Undefined, **kwds)¶

LegendResolveMap schema wrapper

Mapping(required=[])

Attributes:	color : ResolveMode fill : ResolveMode opacity : ResolveMode shape : ResolveMode size : ResolveMode stroke : ResolveMode

resolve_scale(color=Undefined, fill=Undefined, opacity=Undefined, shape=Undefined, size=Undefined, stroke=Undefined, x=Undefined, y=Undefined, **kwds)¶

ScaleResolveMap schema wrapper

Mapping(required=[])

Attributes:	color : ResolveMode fill : ResolveMode opacity : ResolveMode shape : ResolveMode size : ResolveMode stroke : ResolveMode x : ResolveMode y : ResolveMode

save(fp, format=None, override_data_transformer=True, scale_factor=1.0, **kwargs)¶

Save a chart to file in a variety of formats

Supported formats are json, html, png, svg

Parameters:

fp : string filename or file-like object: file in which to write the chart.
format : string (optional): the format to write: one of [‘json’, ‘html’, ‘png’, ‘svg’]. If not specified, the format will be determined from the filename.
override_data_transformer : boolean (optional): If True (default), then the save action will be done with the default data_transformer with max_rows set to None. If False, then use the currently active data transformer.
scale_factor : float: For svg or png formats, scale the image by this factor when saving. This can be used to control the size or resolution of the output. Default is 1.0
**kwargs :: Additional keyword arguments are passed to the output method associated with the specified format.

savechart(fp, format=None, **kwargs)¶

Save a chart to file in a variety of formats

Supported formats are json, html, png, svg

Parameters:	fp : string filename or file-like object file in which to write the chart. format : string (optional) the format to write: one of [‘json’, ‘html’, ‘png’, ‘svg’]. If not specified, the format will be determined from the filename. **kwargs : Additional keyword arguments are passed to the output method associated with the specified format.

serve(ip='127.0.0.1', port=8888, n_retries=50, files=None, jupyter_warning=True, open_browser=True, http_server=None, **kwargs)¶

Open a browser window and display a rendering of the chart

Parameters:

html : string: HTML to serve
ip : string (default = ‘127.0.0.1’): ip address at which the HTML will be served.
port : int (default = 8888): the port at which to serve the HTML
n_retries : int (default = 50): the number of nearby ports to search if the specified port is already in use.
files : dictionary (optional): dictionary of extra content to serve
jupyter_warning : bool (optional): if True (default), then print a warning if this is used within the Jupyter notebook
open_browser : bool (optional): if True (default), then open a web browser to the given HTML
http_server : class (optional): optionally specify an HTTPServer class to use for showing the figure. The default is Python’s basic HTTPServer.
**kwargs :: additional keyword arguments passed to the save() method

to_dict(*args, **kwargs)¶: Convert the chart to a dictionary suitable for JSON export

transform_aggregate(aggregate=Undefined, groupby=Undefined, **kwds)¶

Add an AggregateTransform to the schema.

Parameters:	aggregate : List(AggregatedFieldDef) Array of objects that define fields to aggregate. groupby : List(string) The data fields to group by. If not specified, a single group containing all data objects will be used. **kwds : additional keywords are converted to aggregates using standard shorthand parsing.
Returns:	self : Chart object returns chart to allow for chaining

See also

alt.AggregateTransform: underlying transform object

Examples

The aggregate transform allows you to specify transforms directly using the same shorthand syntax as used in encodings:

>>> import altair as alt
>>> chart1 = alt.Chart().transform_aggregate(
...     mean_acc='mean(Acceleration)',
...     groupby=['Origin']
... )
>>> print(chart1.transform[0].to_json())  
{
  "aggregate": [
    {
      "as": "mean_acc",
      "field": "Acceleration",
      "op": "mean"
    }
  ],
  "groupby": [
    "Origin"
  ]
}

It also supports including AggregatedFieldDef instances or dicts directly, so you can create the above transform like this:

>>> chart2 = alt.Chart().transform_aggregate(
...     [alt.AggregatedFieldDef(field='Acceleration', op='mean',
...                             **{'as': 'mean_acc'})],
...     groupby=['Origin']
... )
>>> chart2.transform == chart1.transform
True

transform_bin(as_=Undefined, field=Undefined, bin=True, **kwargs)¶

Add a BinTransform to the schema.

Returns:	self : Chart object returns chart to allow for chaining

See also

alt.BinTransform: underlying transform object

Examples

>>> import altair as alt
>>> chart = alt.Chart().transform_bin("x_binned", "x")
>>> chart.transform[0]
BinTransform({
  as: 'x_binned',
  bin: True,
  field: 'x'
})

>>> chart = alt.Chart().transform_bin("x_binned", "x",
...                                   bin=alt.Bin(maxbins=10))
>>> chart.transform[0]
BinTransform({
  as: 'x_binned',
  bin: BinParams({
    maxbins: 10
  }),
  field: 'x'
})

Attributes:	as_ : string The output fields at which to write the start and end bin values. bin : anyOf(boolean, BinParams) An object indicating bin properties, or simply true for using default bin parameters. field : string The data field to bin.

transform_calculate(as_=Undefined, calculate=Undefined, **kwargs)¶

Add a CalculateTransform to the schema.

Returns:	self : Chart object returns chart to allow for chaining

See also

alt.CalculateTransform: underlying transform object

Examples

>>> import altair as alt
>>> from altair import datum, expr

>>> chart = alt.Chart().transform_calculate(y = 2 * expr.sin(datum.x))
>>> chart.transform[0]
CalculateTransform({
  as: 'y',
  calculate: (2 * sin(datum.x))
})

It’s also possible to pass the CalculateTransform arguments directly:

>>> kwds = {'as': 'y', 'calculate': '2 * sin(datum.x)'}
>>> chart = alt.Chart().transform_calculate(**kwds)
>>> chart.transform[0]
CalculateTransform({
  as: 'y',
  calculate: '2 * sin(datum.x)'
})

As the first form is easier to write and understand, that is the recommended method.

Attributes:	as_ : string The output fields at which to write the start and end bin values. calculate : string or alt.expr expression An expression string. Use the variable datum to refer to the current data object. **kwargs transforms can also be passed by keyword argument; see Examples

transform_filter(filter, **kwargs)¶

Add a FilterTransform to the schema.

Returns:	self : Chart object returns chart to allow for chaining

See also

alt.FilterTransform: underlying transform object

Attributes:	filter : a filter expression The filter property must be one of the predicate definitions: (1) a string or alt.expr expression (2) a range predicate (3) a selection predicate (4) a logical operand combining (1)-(3) (5) a NamedSelection object

transform_lookup(as_=Undefined, from_=Undefined, lookup=Undefined, default=Undefined, **kwargs)¶

Add a LookupTransform to the schema

Returns:	self : Chart object returns chart to allow for chaining

See also

alt.LookupTransform: underlying transform object

Attributes:

as_ : string or List(string): The field or fields for storing the computed formula value. If from.fields is specified, the transform will use the same names for as. If from.fields is not specified, as has to be a string and we put the whole object into the data under the specified name.
from_ : LookupData: Secondary data reference.
lookup : string: Key in primary data source.
default : string: The default value to use if lookup fails

transform_timeunit(as_=Undefined, field=Undefined, timeUnit=Undefined, **kwargs)¶

Add a TimeUnitTransform to the schema.

Returns:	self : Chart object returns chart to allow for chaining

See also

alt.TimeUnitTransform: underlying transform object

Examples

>>> import altair as alt
>>> from altair import datum, expr

>>> chart = alt.Chart().transform_timeunit(month='month(date)')
>>> chart.transform[0]
TimeUnitTransform({
  as: 'month',
  field: 'date',
  timeUnit: 'month'
})

It’s also possible to pass the TimeUnitTransform arguments directly; this is most useful in cases where the desired field name is not a valid python identifier:

>>> kwds = {'as': 'month', 'timeUnit': 'month', 'field': 'The Month'}
>>> chart = alt.Chart().transform_timeunit(**kwds)
>>> chart.transform[0]
TimeUnitTransform({
  as: 'month',
  field: 'The Month',
  timeUnit: 'month'
})

As the first form is easier to write and understand, that is the recommended method.

Attributes:	as_ : string The output fields at which to write the start and end bin values. field : string The data field to apply time unit. timeUnit : TimeUnit The timeUnit. **kwargs transforms can also be passed by keyword argument; see Examples

transform_window(window=Undefined, frame=Undefined, groupby=Undefined, ignorePeers=Undefined, sort=Undefined, **kwargs)¶

Add a WindowTransform to the schema

Examples

A cumulative line chart

>>> import altair as alt
>>> import numpy as np
>>> import pandas as pd
>>> data = pd.DataFrame({'x': np.arange(100),
...                      'y': np.random.randn(100)})
>>> chart = alt.Chart(data).mark_line().encode(
...     x='x:Q',
...     y='ycuml:Q'
... ).transform_window(
...     ycuml='sum(y)'
... )
>>> chart.transform[0]
WindowTransform({
  window: [WindowFieldDef({
    as: 'ycuml',
    field: 'y',
    op: 'sum'
  })]
})

Attributes:

window : List(WindowFieldDef)

The definition of the fields in the window, and what calculations to use.

frame : List(anyOf(None, float))

A frame specification as a two-element array indicating how the sliding window should proceed. The array entries should either be a number indicating the offset from the current data object, or null to indicate unbounded rows preceding or following the current data object. The default value is [null, 0], indicating that the sliding window includes the current object and all preceding objects. The value [-5, 5] indicates that the window should include five objects preceding and five objects following the current object. Finally, [null, null] indicates that the window frame should always include all data objects. The only operators affected are the aggregation operations and the first_value, last_value, and

nth_value window operations. The other window operations are not affected by

this.

Default value: : [null, 0] (includes the current object and all preceding objects)

groupby : List(string)

The data fields for partitioning the data objects into separate windows. If unspecified, all data points will be a single group.

ignorePeers : boolean

Indicates if the sliding window frame should ignore peer values. (Peer values are those considered identical by the sort criteria). The default is false, causing the window frame to expand to include all peer values. If set to true, the window frame will be defined by offset values only. This setting only affects those operations that depend on the window frame, namely aggregation operations and the first_value, last_value, and nth_value window operations.

Default value: false

sort : List(SortField)

A sort field definition for sorting data objects within a window. If two data objects are considered equal by the comparator, they are considered “peer” values of

equal rank. If sort is not specified, the order is undefined: data objects are

processed in the order they are observed and none are considered peers (the ignorePeers parameter is ignored and treated as if set to true ).

**kwargs

transforms can also be passed by keyword argument; see Examples

class altair.TopLevelRepeatSpec(repeat=Undefined, spec=Undefined, align=Undefined, autosize=Undefined, background=Undefined, bounds=Undefined, center=Undefined, config=Undefined, data=Undefined, datasets=Undefined, description=Undefined, name=Undefined, padding=Undefined, resolve=Undefined, spacing=Undefined, title=Undefined, transform=Undefined, **kwds)¶

TopLevelRepeatSpec schema wrapper

Mapping(required=[repeat, spec])

Attributes:

repeat : Repeat

An object that describes what fields should be repeated into views that are laid out as a row or column.

spec : Spec

align : anyOf(VgLayoutAlign, RowColVgLayoutAlign)

The alignment to apply to grid rows and columns. The supported string values are "all", "each", and "none". * For "none", a flow layout will be used, in which adjacent subviews are simply placed one after the other. * For "each", subviews will be aligned into a clean grid structure, but each row or column may be of variable size. * For "all", subviews will be aligned and each row or column will be sized identically based on the maximum observed size. String values for this property will be applied to both grid rows and columns. Alternatively, an object value of the form {"row": string, "column": string} can

be used to supply different alignments for rows and columns. Default value:

"all".

autosize : anyOf(AutosizeType, AutoSizeParams)

Sets how the visualization size should be determined. If a string, should be one of "pad", "fit" or "none". Object values can additionally specify parameters for content sizing and automatic resizing. "fit" is only supported for single and layered views that don’t use rangeStep.

Default value : pad

background : string

<<<<<<< HEAD

CSS color property to use as the background of visualization.

Default value: none (transparent)

=======

CSS color property to use as the background of visualization. Default value: none (transparent)

bounds : enum(‘full’, ‘flush’): The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"
center : anyOf(boolean, RowColboolean): Boolean flag indicating if subviews should be centered relative to their respective rows or columns. An object value of the form {"row": boolean, "column": boolean} can be used to supply different centering values for rows and columns. Default value: false

>>>>>>> altair-viz/master

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

data : Data

An object describing the data source

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

resolve : Resolve

Scale and legend resolutions for repeated charts.

spacing : anyOf(float, RowColnumber)

The spacing in pixels between sub-views of the composition operator. An object of the form {"row": number, "column": number} can be used to set different spacing values for rows and columns. Default value : 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

$schema : string

URL to JSON schema for a Vega-Lite specification. Unless you have a reason to change this, use https://vega.github.io/schema/vega-lite/v2.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

class altair.TopLevelSpec(*args, **kwds)¶

TopLevelSpec schema wrapper

anyOf(TopLevelFacetedUnitSpec, TopLevelFacetSpec, TopLevelLayerSpec, TopLevelRepeatSpec, TopLevelVConcatSpec, TopLevelHConcatSpec)

class altair.TopLevelVConcatSpec(vconcat=Undefined, autosize=Undefined, background=Undefined, bounds=Undefined, center=Undefined, config=Undefined, data=Undefined, datasets=Undefined, description=Undefined, name=Undefined, padding=Undefined, resolve=Undefined, spacing=Undefined, title=Undefined, transform=Undefined, **kwds)¶

TopLevelVConcatSpec schema wrapper

Mapping(required=[vconcat])

Attributes:

vconcat : List(Spec)

A list of views that should be concatenated and put into a column.

autosize : anyOf(AutosizeType, AutoSizeParams)

Sets how the visualization size should be determined. If a string, should be one of "pad", "fit" or "none". Object values can additionally specify parameters for content sizing and automatic resizing. "fit" is only supported for single and layered views that don’t use rangeStep.

Default value : pad

background : string

<<<<<<< HEAD

CSS color property to use as the background of visualization.

Default value: none (transparent)

=======

CSS color property to use as the background of visualization. Default value: none (transparent)

bounds : enum(‘full’, ‘flush’): The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"
center : boolean: Boolean flag indicating if subviews should be centered relative to their respective rows or columns. Default value: false

>>>>>>> altair-viz/master

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

data : Data

An object describing the data source

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

resolve : Resolve

Scale, axis, and legend resolutions for vertically concatenated charts.

spacing : float

The spacing in pixels between sub-views of the concat operator. Default value :: 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

$schema : string

URL to JSON schema for a Vega-Lite specification. Unless you have a reason to change this, use https://vega.github.io/schema/vega-lite/v2.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

class altair.TopoDataFormat(feature=Undefined, mesh=Undefined, parse=Undefined, type=Undefined, **kwds)¶

TopoDataFormat schema wrapper

Mapping(required=[])

Attributes:

feature : string

The name of the TopoJSON object set to convert to a GeoJSON feature collection. For example, in a map of the world, there may be an object set named "countries". Using the feature property, we can extract this set and generate a GeoJSON feature object for each country.

mesh : string

The name of the TopoJSON object set to convert to mesh. Similar to the feature option, mesh extracts a named TopoJSON object set. Unlike the feature option, the corresponding geo data is returned as a single, unified mesh instance, not as individual GeoJSON features. Extracting a mesh is useful for more efficiently drawing borders or other geographic elements that you do not need to associate with specific regions such as individual countries, states or counties.

parse : anyOf(enum(‘auto’), Parse, None)

If set to "auto" (the default), perform automatic type inference to determine the desired data types. If set to null, disable type inference based on the spec and only use type inference based on the data. Alternatively, a parsing directive object can be provided for explicit data types. Each property of the object corresponds to a field name, and the value to the desired data type (one of "number", "boolean", "date", or null (do not parse the field)). For example, "parse": {"modified_on": "date"} parses the modified_on field in each input record a Date value.

For "date", we parse data based using Javascript’s Date.parse(). For Specific date formats can be provided (e.g., {foo: 'date:"%m%d%Y"'} ), using the d3-time-format syntax. UTC date format parsing is supported similarly (e.g., {foo: 'utc:"%m%d%Y"'} ). See more about UTC time

type : enum(‘topojson’)

Type of input data: "json", "csv", "tsv", "dsv". The default format type is determined by the extension of the file URL. If no extension is detected, "json" will be used by default.

class altair.Transform(*args, **kwds)¶

Transform schema wrapper

anyOf(FilterTransform, CalculateTransform, LookupTransform, BinTransform, TimeUnitTransform, AggregateTransform, WindowTransform)

class altair.Type(*args, **kwds)¶

Type schema wrapper

anyOf(BasicType, GeoType) Constants and utilities for data type

Data type based on level of measurement

class altair.UrlData(url=Undefined, format=Undefined, name=Undefined, **kwds)¶

UrlData schema wrapper

Mapping(required=[url])

Attributes:	url : string An URL from which to load the data set. Use the `format.type` property to ensure the loaded data is correctly parsed. format : DataFormat An object that specifies the format for parsing the data. name : string Provide a placeholder name and bind data at runtime.

class altair.UtcMultiTimeUnit(*args)¶

UtcMultiTimeUnit schema wrapper

enum(‘utcyearquarter’, ‘utcyearquartermonth’, ‘utcyearmonth’, ‘utcyearmonthdate’, ‘utcyearmonthdatehours’, ‘utcyearmonthdatehoursminutes’, ‘utcyearmonthdatehoursminutesseconds’, ‘utcquartermonth’, ‘utcmonthdate’, ‘utchoursminutes’, ‘utchoursminutesseconds’, ‘utcminutesseconds’, ‘utcsecondsmilliseconds’)

class altair.UtcSingleTimeUnit(*args)¶

UtcSingleTimeUnit schema wrapper

enum(‘utcyear’, ‘utcquarter’, ‘utcmonth’, ‘utcday’, ‘utcdate’, ‘utchours’, ‘utcminutes’, ‘utcseconds’, ‘utcmilliseconds’)

class altair.VConcatChart(data=Undefined, vconcat=(), **kwargs)

A chart with vertically-concatenated facets: Mapping(required=[vconcat])

Attributes:

vconcat : List(Spec)

A list of views that should be concatenated and put into a column.

autosize : anyOf(AutosizeType, AutoSizeParams)

Sets how the visualization size should be determined. If a string, should be one of "pad", "fit" or "none". Object values can additionally specify parameters for content sizing and automatic resizing. "fit" is only supported for single and layered views that don’t use rangeStep.

Default value : pad

background : string

<<<<<<< HEAD

CSS color property to use as the background of visualization.

Default value: none (transparent)

=======

CSS color property to use as the background of visualization. Default value: none (transparent)

bounds : enum(‘full’, ‘flush’): The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"
center : boolean: Boolean flag indicating if subviews should be centered relative to their respective rows or columns. Default value: false

>>>>>>> altair-viz/master

config : Config

Vega-Lite configuration object. This property can only be defined at the top-level of a specification.

data : Data

An object describing the data source

datasets : Datasets

A global data store for named datasets. This is a mapping from names to inline datasets. This can be an array of objects or primitive values or a string. Arrays of primitive values are ingested as objects with a data property.

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

padding : Padding

The default visualization padding, in pixels, from the edge of the visualization canvas to the data rectangle. If a number, specifies padding for all sides. If an object, the value should have the format {"left": 5, "top": 5, "right": 5, "bottom": 5} to specify padding for each side of the visualization.

Default value : 5

resolve : Resolve

Scale, axis, and legend resolutions for vertically concatenated charts.

spacing : float

The spacing in pixels between sub-views of the concat operator. Default value :: 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

$schema : string

URL to JSON schema for a Vega-Lite specification. Unless you have a reason to change this, use https://vega.github.io/schema/vega-lite/v2.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

class altair.VConcatSpec(vconcat=Undefined, bounds=Undefined, center=Undefined, data=Undefined, description=Undefined, name=Undefined, resolve=Undefined, spacing=Undefined, title=Undefined, transform=Undefined, **kwds)¶

VConcatSpec schema wrapper

Mapping(required=[vconcat])

Attributes:

vconcat : List(Spec)

A list of views that should be concatenated and put into a column.

bounds : enum(‘full’, ‘flush’)

The bounds calculation method to use for determining the extent of a sub-plot. One of full (the default) or flush. * If set to full, the entire calculated bounds (including axes, title, and legend) will be used. * If set to flush, only the specified width and height values for the sub-view will be used.

The flush setting can be useful when attempting to place sub-plots without axes or legends into a uniform grid structure. Default value: "full"

center : boolean

Boolean flag indicating if subviews should be centered relative to their respective rows or columns. Default value: false

data : Data

An object describing the data source

description : string

Description of this mark for commenting purpose.

name : string

Name of the visualization for later reference.

resolve : Resolve

Scale, axis, and legend resolutions for vertically concatenated charts.

spacing : float

The spacing in pixels between sub-views of the concat operator. Default value :: 10

title : anyOf(string, TitleParams)

Title for the plot.

transform : List(Transform)

An array of data transformations such as filter and new field calculation.

class altair.ValueDef(value=Undefined, **kwds)¶

ValueDef schema wrapper

Mapping(required=[value]) Definition object for a constant value of an encoding channel.

Attributes:	value : anyOf(float, string, boolean) A constant value in visual domain (e.g., `"red"` / “#0099ff” for color, values between `0` to `1` for opacity).

class altair.ValueDefWithCondition(condition=Undefined, value=Undefined, **kwds)¶

ValueDefWithCondition schema wrapper

Mapping(required=[]) A ValueDef with Condition<ValueDef | FieldDef>

Attributes:	condition : anyOf(ConditionalFieldDef, ConditionalValueDef, List(ConditionalValueDef)) A field definition or one or more value definition(s) with a selection predicate. value : anyOf(float, string, boolean) A constant value in visual domain.

class altair.VegaLite(spec, validate=False)¶: An IPython/Jupyter display class for rendering VegaLite 2.

class altair.VegaLiteSchema(*args, **kwds)¶

class altair.VerticalAlign(*args)¶

VerticalAlign schema wrapper

enum(‘top’, ‘middle’, ‘bottom’)

class altair.VgAxisConfig(bandPosition=Undefined, domain=Undefined, domainColor=Undefined, domainWidth=Undefined, grid=Undefined, gridColor=Undefined, gridDash=Undefined, gridOpacity=Undefined, gridWidth=Undefined, labelAngle=Undefined, labelBound=Undefined, labelColor=Undefined, labelFlush=Undefined, labelFont=Undefined, labelFontSize=Undefined, labelLimit=Undefined, labelOverlap=Undefined, labelPadding=Undefined, labels=Undefined, maxExtent=Undefined, minExtent=Undefined, tickColor=Undefined, tickRound=Undefined, tickSize=Undefined, tickWidth=Undefined, ticks=Undefined, titleAlign=Undefined, titleAngle=Undefined, titleBaseline=Undefined, titleColor=Undefined, titleFont=Undefined, titleFontSize=Undefined, titleFontWeight=Undefined, titleLimit=Undefined, titleMaxLength=Undefined, titlePadding=Undefined, titleX=Undefined, titleY=Undefined, **kwds)¶

VgAxisConfig schema wrapper

Mapping(required=[])

Attributes:

bandPosition : float

An interpolation fraction indicating where, for band scales, axis ticks should be positioned. A value of 0 places ticks at the left edge of their bands. A value of 0.5 places ticks in the middle of their bands.

domain : boolean

A boolean flag indicating if the domain (the axis baseline) should be included as part of the axis.

Default value: true

domainColor : string

Color of axis domain line.

Default value: (none, using Vega default).

domainWidth : float

Stroke width of axis domain line

Default value: (none, using Vega default).

grid : boolean

A boolean flag indicating if grid lines should be included as part of the axis

Default value: true for continuous scales that are not binned; otherwise, false.

gridColor : string

Color of gridlines.

gridDash : List(float)

The offset (in pixels) into which to begin drawing with the grid dash array.

gridOpacity : float

The stroke opacity of grid (value between [0,1])

Default value: ( 1 by default)

gridWidth : float

The grid width, in pixels.

labelAngle : float

The rotation angle of the axis labels.

Default value: -90 for nominal and ordinal fields; 0 otherwise.

labelBound : anyOf(boolean, float)

Indicates if labels should be hidden if they exceed the axis range. If false (the default) no bounds overlap analysis is performed. If true, labels will be hidden if they exceed the axis range by more than 1 pixel. If this property is a number, it specifies the pixel tolerance: the maximum amount by which a label bounding box may exceed the axis range.

Default value: false.

labelColor : string

The color of the tick label, can be in hex color code or regular color name.

labelFlush : anyOf(boolean, float)

Indicates if the first and last axis labels should be aligned flush with the scale range. Flush alignment for a horizontal axis will left-align the first label and right-align the last label. For vertical axes, bottom and top text baselines are applied instead. If this property is a number, it also indicates the number of pixels by which to offset the first and last labels; for example, a value of 2 will flush-align the first and last labels and also push them 2 pixels outward from the center of the axis. The additional adjustment can sometimes help the labels better visually group with corresponding axis ticks.

Default value: true for axis of a continuous x-scale. Otherwise, false.

labelFont : string

The font of the tick label.

labelFontSize : float

The font size of the label, in pixels.

labelLimit : float

Maximum allowed pixel width of axis tick labels.

labelOverlap : anyOf(boolean, enum(‘parity’), enum(‘greedy’))

The strategy to use for resolving overlap of axis labels. If false (the default), no overlap reduction is attempted. If set to true or "parity", a strategy of removing every other label is used (this works well for standard linear axes). If set to "greedy", a linear scan of the labels is performed, removing any labels that overlaps with the last visible label (this often works better for log-scaled axes).

Default value: true for non-nominal fields with non-log scales; "greedy" for log scales; otherwise false.

labelPadding : float

The padding, in pixels, between axis and text labels.

labels : boolean

A boolean flag indicating if labels should be included as part of the axis.

Default value: true.

maxExtent : float

The maximum extent in pixels that axis ticks and labels should use. This determines a maximum offset value for axis titles.

Default value: undefined.

minExtent : float

The minimum extent in pixels that axis ticks and labels should use. This determines a minimum offset value for axis titles.

Default value: 30 for y-axis; undefined for x-axis.

tickColor : string

The color of the axis’s tick.

tickRound : boolean

Boolean flag indicating if pixel position values should be rounded to the nearest integer.

tickSize : float

The size in pixels of axis ticks.

tickWidth : float

The width, in pixels, of ticks.

ticks : boolean

Boolean value that determines whether the axis should include ticks.

titleAlign : string

Horizontal text alignment of axis titles.

titleAngle : float

Angle in degrees of axis titles.

titleBaseline : string

Vertical text baseline for axis titles.

titleColor : string

Color of the title, can be in hex color code or regular color name.

titleFont : string

Font of the title. (e.g., "Helvetica Neue" ).

titleFontSize : float

Font size of the title.

titleFontWeight : FontWeight

Font weight of the title. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

titleLimit : float

Maximum allowed pixel width of axis titles.

titleMaxLength : float

Max length for axis title if the title is automatically generated from the field’s description.

titlePadding : float

The padding, in pixels, between title and axis.

titleX : float

X-coordinate of the axis title relative to the axis group.

titleY : float

Y-coordinate of the axis title relative to the axis group.

class altair.VgBinding(*args, **kwds)¶

VgBinding schema wrapper

anyOf(VgCheckboxBinding, VgRadioBinding, VgSelectBinding, VgRangeBinding, VgGenericBinding)

class altair.VgCheckboxBinding(input=Undefined, element=Undefined, **kwds)¶

VgCheckboxBinding schema wrapper

Mapping(required=[input])

Attributes:	input : enum(‘checkbox’) element : string

class altair.VgComparatorOrder(*args)¶

VgComparatorOrder schema wrapper

enum(‘ascending’, ‘descending’)

class altair.VgEventStream(**kwds)¶

VgEventStream schema wrapper

Mapping(required=[])

class altair.VgGenericBinding(input=Undefined, element=Undefined, **kwds)¶

VgGenericBinding schema wrapper

Mapping(required=[input])

Attributes:	input : string element : string

class altair.VgLayoutAlign(*args)¶

VgLayoutAlign schema wrapper

enum(‘none’, ‘each’, ‘all’)

class altair.VgMarkConfig(align=Undefined, angle=Undefined, baseline=Undefined, cornerRadius=Undefined, cursor=Undefined, dir=Undefined, dx=Undefined, dy=Undefined, ellipsis=Undefined, fill=Undefined, fillOpacity=Undefined, font=Undefined, fontSize=Undefined, fontStyle=Undefined, fontWeight=Undefined, href=Undefined, interpolate=Undefined, limit=Undefined, opacity=Undefined, orient=Undefined, radius=Undefined, shape=Undefined, size=Undefined, stroke=Undefined, strokeCap=Undefined, strokeDash=Undefined, strokeDashOffset=Undefined, strokeJoin=Undefined, strokeMiterLimit=Undefined, strokeOpacity=Undefined, strokeWidth=Undefined, tension=Undefined, text=Undefined, theta=Undefined, tooltip=Undefined, **kwds)¶

VgMarkConfig schema wrapper

Mapping(required=[])

Attributes:

align : HorizontalAlign

The horizontal alignment of the text. One of "left", "right", "center".

angle : float

The rotation angle of the text, in degrees.

baseline : VerticalAlign

The vertical alignment of the text. One of "top", "middle", "bottom".

Default value: "middle"

cornerRadius : float

The radius in pixels of rounded rectangle corners. Default value: 0

cursor : Cursor

The mouse cursor used over the mark. Any valid CSS cursor type can be used.

dir : Dir

The direction of the text. One of "ltr" (left-to-right) or "rtl" (right-to-left). This property determines on which side is truncated in response to the limit parameter. Default value: "ltr"

dx : float

The horizontal offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

dy : float

The vertical offset, in pixels, between the text label and its anchor point. The offset is applied after rotation by the angle property.

ellipsis : string

The ellipsis string for text truncated in response to the limit parameter. Default value: "…"

fill : string

Default Fill Color. This has higher precedence than config.color

Default value: (None)

fillOpacity : float

The fill opacity (value between [0,1]).

Default value: 1

font : string

The typeface to set the text in (e.g., "Helvetica Neue" ).

fontSize : float

The font size, in pixels.

fontStyle : FontStyle

The font style (e.g., "italic" ).

fontWeight : FontWeight

The font weight. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

href : string

A URL to load upon mouse click. If defined, the mark acts as a hyperlink.

interpolate : Interpolate

The line interpolation method to use for line and area marks. One of the following:

"linear" : piecewise linear segments, as in a polyline.
"linear-closed" : close the linear segments to form a polygon.
"step" : alternate between horizontal and vertical segments, as in a step function.
"step-before" : alternate between vertical and horizontal segments, as in a step function.
"step-after" : alternate between horizontal and vertical segments, as in a step function.
"basis" : a B-spline, with control point duplication on the ends.
"basis-open" : an open B-spline; may not intersect the start or end.
"basis-closed" : a closed B-spline, as in a loop.
"cardinal" : a Cardinal spline, with control point duplication on the ends.
"cardinal-open" : an open Cardinal spline; may not intersect the start or end, but will intersect other control points.
"cardinal-closed" : a closed Cardinal spline, as in a loop.
"bundle" : equivalent to basis, except the tension parameter is used to straighten the spline.
"monotone" : cubic interpolation that preserves monotonicity in y.

limit : float

The maximum length of the text mark in pixels. The text value will be automatically truncated if the rendered size exceeds the limit. Default value: 0, indicating no limit

opacity : float

The overall opacity (value between [0,1]).

Default value: 0.7 for non-aggregate plots with point, tick, circle, or square marks or layered bar charts and 1 otherwise.

orient : Orient

The orientation of a non-stacked bar, tick, area, and line charts. The value is either horizontal (default) or vertical.

For bar, rule and tick, this determines whether the size of the bar and tick

should be applied to x or y dimension. * For area, this property determines the orient property of the Vega output. * For line and trail marks, this property determines the sort order of the points in

the line

if config.sortLineBy is not specified. For stacked charts, this is always determined by the orientation of the stack; therefore explicitly specified value will be ignored.

radius : float

Polar coordinate radial offset, in pixels, of the text label from the origin determined by the x and y properties.

shape : string

The default symbol shape to use. One of: "circle" (default), "square", "cross", "diamond", "triangle-up", or "triangle-down", or a custom SVG path.

Default value: "circle"

size : float

The pixel area each the point/circle/square. For example: in the case of circles, the radius is determined in part by the square root of the size value.

Default value: 30

stroke : string

<<<<<<< HEAD

Default Stroke Color. This has higher precedence than config.color

Default value: (None)

strokeCap : enum(‘butt’, ‘round’, ‘square’)

=======

Default Stroke Color. This has higher precedence than config.color Default value: (None)

strokeCap : StrokeCap

>>>>>>> altair-viz/master

The stroke cap for line ending style. One of "butt", "round", or "square".

Default value: "square"

strokeDash : List(float)

An array of alternating stroke, space lengths for creating dashed or dotted lines.

strokeDashOffset : float

The offset (in pixels) into which to begin drawing with the stroke dash array.

strokeJoin : StrokeJoin

The stroke line join method. One of "miter", "round" or "bevel". Default value: "miter"

strokeMiterLimit : float

The miter limit at which to bevel a line join.

strokeOpacity : float

The stroke opacity (value between [0,1]).

Default value: 1

strokeWidth : float

The stroke width, in pixels.

tension : float

Depending on the interpolation type, sets the tension parameter (for line and area marks).

text : string

Placeholder text if the text channel is not specified

theta : float

Polar coordinate angle, in radians, of the text label from the origin determined by the x and y properties. Values for theta follow the same convention of arc mark startAngle and endAngle properties: angles are measured in radians, with 0 indicating “north”.

tooltip : Mapping(required=[])

The tooltip text to show upon mouse hover.

class altair.VgProjectionType(*args)¶

VgProjectionType schema wrapper

enum(‘albers’, ‘albersUsa’, ‘azimuthalEqualArea’, ‘azimuthalEquidistant’, ‘conicConformal’, ‘conicEqualArea’, ‘conicEquidistant’, ‘equirectangular’, ‘gnomonic’, ‘mercator’, ‘orthographic’, ‘stereographic’, ‘transverseMercator’)

class altair.VgRadioBinding(input=Undefined, options=Undefined, element=Undefined, **kwds)¶

VgRadioBinding schema wrapper

Mapping(required=[input, options])

Attributes:	input : enum(‘radio’) options : List(string) element : string

class altair.VgRangeBinding(input=Undefined, element=Undefined, max=Undefined, min=Undefined, step=Undefined, **kwds)¶

VgRangeBinding schema wrapper

Mapping(required=[input])

Attributes:	input : enum(‘range’) element : string max : float min : float step : float

class altair.VgScheme(scheme=Undefined, count=Undefined, extent=Undefined, **kwds)¶

VgScheme schema wrapper

Mapping(required=[scheme])

Attributes:	scheme : string count : float extent : List(float)

class altair.VgSelectBinding(input=Undefined, options=Undefined, element=Undefined, **kwds)¶

VgSelectBinding schema wrapper

Mapping(required=[input, options])

Attributes:	input : enum(‘select’) options : List(string) element : string

class altair.VgTitleConfig(anchor=Undefined, angle=Undefined, baseline=Undefined, color=Undefined, font=Undefined, fontSize=Undefined, fontWeight=Undefined, limit=Undefined, offset=Undefined, orient=Undefined, **kwds)¶

VgTitleConfig schema wrapper

Mapping(required=[])

Attributes:

anchor : Anchor

The anchor position for placing the title. One of "start", "middle", or "end". For example, with an orientation of top these anchor positions map to a left-, center-, or right-aligned title.

Default value: "middle" for single and layered views. "start" for other composite views.

Note: For now, anchor is only customizable only for single and layered views. For other composite views, anchor is always "start".

angle : float

Angle in degrees of title text.

baseline : VerticalAlign

Vertical text baseline for title text.

color : string

Text color for title text.

font : string

Font name for title text.

fontSize : float

Font size in pixels for title text.

Default value: 10.

fontWeight : FontWeight

Font weight for title text. This can be either a string (e.g "bold", "normal" ) or a number ( 100, 200, 300, …, 900 where "normal" = 400 and "bold" = 700 ).

limit : float

The maximum allowed length in pixels of legend labels.

offset : float

Offset in pixels of the title from the chart body and axes.

orient : TitleOrient

Default title orientation (“top”, “bottom”, “left”, or “right”)

class altair.ViewConfig(clip=Undefined, fill=Undefined, fillOpacity=Undefined, height=Undefined, stroke=Undefined, strokeDash=Undefined, strokeDashOffset=Undefined, strokeJoin=Undefined, strokeMiterLimit=Undefined, strokeOpacity=Undefined, strokeWidth=Undefined, width=Undefined, **kwds)¶

ViewConfig schema wrapper

Mapping(required=[])

Attributes:

clip : boolean

Whether the view should be clipped.

fill : string

The fill color.

Default value: (none)

fillOpacity : float

The fill opacity (value between [0,1]).

Default value: (none)

height : float

The default height of the single plot or each plot in a trellis plot when the visualization has a continuous (non-ordinal) y-scale with rangeStep = null.

Default value: 200

stroke : string

The stroke color.

Default value: (none)

strokeDash : List(float)

An array of alternating stroke, space lengths for creating dashed or dotted lines.

Default value: (none)

strokeDashOffset : float

The offset (in pixels) into which to begin drawing with the stroke dash array.

Default value: (none)

strokeJoin : StrokeJoin

The stroke line join method. One of miter (default), round or bevel. Default value: ‘miter’

strokeMiterLimit : float

The stroke line join method. One of miter (default), round or bevel. Default value: ‘miter’

strokeOpacity : float

The stroke opacity (value between [0,1]).

Default value: (none)

strokeWidth : float

The stroke width, in pixels.

Default value: (none)

width : float

The default width of the single plot or each plot in a trellis plot when the visualization has a continuous (non-ordinal) x-scale or ordinal x-scale with rangeStep = null.

Default value: 200

class altair.WindowFieldDef(op=Undefined, field=Undefined, param=Undefined, **kwds)¶

WindowFieldDef schema wrapper

Mapping(required=[op, as])

Attributes:

op : anyOf(AggregateOp, WindowOnlyOp)

The window or aggregation operations to apply within a window, including rank, lead, sum, average or count. See the list of all supported operations here.

field : string

The data field for which to compute the aggregate or window function. This can be omitted for window functions that do not operate over a field such as count, rank, dense_rank.

param : float

Parameter values for the window functions. Parameter values can be omitted for operations that do not accept a parameter.

See the list of all supported operations and their parameters here.

as : string

The output name for the window operation.

class altair.WindowOnlyOp(*args)¶

WindowOnlyOp schema wrapper

enum(‘row_number’, ‘rank’, ‘dense_rank’, ‘percent_rank’, ‘cume_dist’, ‘ntile’, ‘lag’, ‘lead’, ‘first_value’, ‘last_value’, ‘nth_value’)

class altair.WindowTransform(window=Undefined, frame=Undefined, groupby=Undefined, ignorePeers=Undefined, sort=Undefined, **kwds)¶

WindowTransform schema wrapper

Mapping(required=[window])

Attributes:

window : List(WindowFieldDef)

The definition of the fields in the window, and what calculations to use.

frame : List(anyOf(None, float))

A frame specification as a two-element array indicating how the sliding window should proceed. The array entries should either be a number indicating the offset from the current data object, or null to indicate unbounded rows preceding or following the current data object. The default value is [null, 0], indicating that the sliding window includes the current object and all preceding objects. The value [-5, 5] indicates that the window should include five objects preceding and five objects following the current object. Finally, [null, null] indicates that the window frame should always include all data objects. The only operators affected are the aggregation operations and the first_value, last_value, and nth_value window operations. The other window operations are not affected by this.

Default value: : [null, 0] (includes the current object and all preceding objects)

groupby : List(string)

The data fields for partitioning the data objects into separate windows. If unspecified, all data points will be in a single group.

ignorePeers : boolean

Indicates if the sliding window frame should ignore peer values. (Peer values are those considered identical by the sort criteria). The default is false, causing the window frame to expand to include all peer values. If set to true, the window frame will be defined by offset values only. This setting only affects those operations that depend on the window frame, namely aggregation operations and the first_value, last_value, and nth_value window operations.

Default value: false

sort : List(SortField)

A sort field definition for sorting data objects within a window. If two data objects are considered equal by the comparator, they are considered “peer” values of equal rank. If sort is not specified, the order is undefined: data objects are processed in the order they are observed and none are considered peers (the ignorePeers parameter is ignored and treated as if set to true ).

class altair.X(shorthand=Undefined, aggregate=Undefined, axis=Undefined, bin=Undefined, field=Undefined, scale=Undefined, sort=Undefined, stack=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

X schema wrapper

Mapping(required=[shorthand])

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

axis : anyOf(Axis, None)

An object defining properties of axis’s gridlines, ticks and labels. If null, the axis for the encoding channel will be removed.

Default value: If undefined, default axis properties are applied.

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

stack : anyOf(StackOffset, None)

Type of stacking offset if the field should be stacked. stack is only applicable for x and y channels with continuous domains. For example, stack of y can be used to customize stacking for a vertical bar chart.

stack can be one of the following values:

“zero”: stacking with baseline offset at zero value of the scale (for creating typical stacked [bar](https://vega.github.io/vega-lite/docs/stack.html#bar) and area chart).
"normalize" - stacking with normalized domain (for creating normalized stacked bar and area charts.

"center" - stacking with center baseline (for `streamgraph

<https://vega.github.io/vega-lite/docs/stack.html#streamgraph>`_ ). * null - No-stacking. This will produce layered `bar

<https://vega.github.io/vega-lite/docs/stack.html#layered-bar-chart>`_ and area chart.

Default value: zero for plots with all of the following conditions are true: (1) the mark is bar or area ; (2) the stacked measure channel (x or y) has a linear scale; (3) At least one of non-position channels mapped to an unaggregated field that is different from x and y. Otherwise, null by default.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.X2(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

X2 schema wrapper

Mapping(required=[shorthand]) Definition object for a data field, its type and transformation of an encoding channel.

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.X2Value(value, **kwds)

X2Value schema wrapper

Mapping(required=[value]) Definition object for a constant value of an encoding channel.

Attributes:	value : anyOf(float, string, boolean) A constant value in visual domain (e.g., `"red"` / “#0099ff” for color, values between `0` to `1` for opacity).

class altair.XValue(value, **kwds)

XValue schema wrapper

Mapping(required=[value]) Definition object for a constant value of an encoding channel.

Attributes:	value : anyOf(float, string, boolean) A constant value in visual domain (e.g., `"red"` / “#0099ff” for color, values between `0` to `1` for opacity).

class altair.Y(shorthand=Undefined, aggregate=Undefined, axis=Undefined, bin=Undefined, field=Undefined, scale=Undefined, sort=Undefined, stack=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

Y schema wrapper

Mapping(required=[shorthand])

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

axis : anyOf(Axis, None)

An object defining properties of axis’s gridlines, ticks and labels. If null, the axis for the encoding channel will be removed.

Default value: If undefined, default axis properties are applied.

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

scale : anyOf(Scale, None)

An object defining properties of the channel’s scale, which is the function that transforms values in the data domain (numbers, dates, strings, etc) to visual values (pixels, colors, sizes) of the encoding channels.

If null, the scale will be disabled and the data value will be directly encoded.

Default value: If undefined, default scale properties are applied.

sort : Sort

Sort order for the encoded field.

For continuous fields (quantitative or temporal), sort can be either "ascending" or "descending".

For discrete fields, sort can be one of the following:

"ascending" or "descending" – for sorting by the values’ natural order in Javascript.
A sort field definition for sorting by another field.
An array specifying the field values in preferred order. In this case, the sort order will obey the values in the array, followed by any unspecified values in their original order. For discrete time field, values in the sort array can be date-time definition objects. In addition, for time units "month" and "day", the values can be the month or day names (case insensitive) or their 3-letter initials (e.g., "Mon", "Tue" ).
null indicating no sort.

Default value: "ascending"

Note: null is not supported for row and column.

stack : anyOf(StackOffset, None)

Type of stacking offset if the field should be stacked. stack is only applicable for x and y channels with continuous domains. For example, stack of y can be used to customize stacking for a vertical bar chart.

stack can be one of the following values:

“zero”: stacking with baseline offset at zero value of the scale (for creating typical stacked [bar](https://vega.github.io/vega-lite/docs/stack.html#bar) and area chart).
"normalize" - stacking with normalized domain (for creating normalized stacked bar and area charts.

"center" - stacking with center baseline (for `streamgraph

<https://vega.github.io/vega-lite/docs/stack.html#streamgraph>`_ ). * null - No-stacking. This will produce layered `bar

<https://vega.github.io/vega-lite/docs/stack.html#layered-bar-chart>`_ and area chart.

Default value: zero for plots with all of the following conditions are true: (1) the mark is bar or area ; (2) the stacked measure channel (x or y) has a linear scale; (3) At least one of non-position channels mapped to an unaggregated field that is different from x and y. Otherwise, null by default.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.Y2(shorthand=Undefined, aggregate=Undefined, bin=Undefined, field=Undefined, timeUnit=Undefined, title=Undefined, type=Undefined, **kwds)

Y2 schema wrapper

Mapping(required=[shorthand]) Definition object for a data field, its type and transformation of an encoding channel.

Attributes:

shorthand : string

shorthand for field, aggregate, and type

aggregate : Aggregate

Aggregation function for the field (e.g., mean, sum, median, min, max, count ).

Default value: undefined (None)

bin : anyOf(boolean, BinParams)

A flag for binning a quantitative field, or an object defining binning parameters. If true, default binning parameters will be applied.

Default value: false

field : anyOf(string, RepeatRef)

Required. A string defining the name of the field from which to pull a data value or an object defining iterated values from the repeat operator.

Note: Dots ( . ) and brackets ( [ and ] ) can be used to access nested objects (e.g., "field": "foo.bar" and "field": "foo['bar']" ). If field names contain dots or brackets but are not nested, you can use \ to escape dots and brackets (e.g., "a\.b" and "a\[0\]" ). See more details about escaping in the field documentation.

Note: field is not required if aggregate is count.

timeUnit : TimeUnit

Time unit (e.g., year, yearmonth, month, hours ) for a temporal field. or a temporal field that gets casted as ordinal.

Default value: undefined (None)

title : anyOf(string, None)

A title for the field. If null, the title will be removed.

Default value: derived from the field’s name and transformation function ( aggregate, bin and timeUnit ). If the field has an aggregate function, the function is displayed as part of the title (e.g., "Sum of Profit" ). If the field is binned or has a time unit applied, the applied function is shown in parentheses (e.g., "Profit (binned)", "Transaction Date (year-month)" ). Otherwise, the title is simply the field name.

Notes :

1) You can customize the default field title format by providing the [fieldTitle property in the config or fieldTitle function via the compile function’s options.

2) If both field definition’s title and axis, header, or legend title are defined, axis/header/legend title will be used.

type : Type

The encoded field’s type of measurement ( "quantitative", "temporal", "ordinal", or "nominal" ). It can also be a "geojson" type for encoding ‘geoshape’.

class altair.Y2Value(value, **kwds)

Y2Value schema wrapper

Mapping(required=[value]) Definition object for a constant value of an encoding channel.

Attributes:	value : anyOf(float, string, boolean) A constant value in visual domain (e.g., `"red"` / “#0099ff” for color, values between `0` to `1` for opacity).

class altair.YValue(value, **kwds)

YValue schema wrapper

Mapping(required=[value]) Definition object for a constant value of an encoding channel.

Attributes:	value : anyOf(float, string, boolean) A constant value in visual domain (e.g., `"red"` / “#0099ff” for color, values between `0` to `1` for opacity).

class altair.curry(*args, **kwargs)¶

Curry a callable function

Enables partial application of arguments through calling a function with an incomplete set of arguments.

>>> def mul(x, y):
...     return x * y
>>> mul = curry(mul)

>>> double = mul(2)
>>> double(10)
20

Also supports keyword arguments

>>> @curry                  # Can use curry as a decorator
... def f(x, y, a=10):
...     return a * (x + y)

>>> add = f(a=1)
>>> add(2, 3)
5

See Also:

toolz.curried - namespace of curried functions: https://toolz.readthedocs.io/en/latest/curry.html

altair.binding(self, *args, **kwds)¶: A generic binding anyOf(VgCheckboxBinding, VgRadioBinding, VgSelectBinding, VgRangeBinding, VgGenericBinding)

altair.binding_checkbox(self, input=Undefined, element=Undefined, **kwds)¶

A checkbox binding Mapping(required=[input])

Attributes:	input : enum(‘checkbox’) element : string

altair.binding_radio(self, input=Undefined, options=Undefined, element=Undefined, **kwds)¶

A radio button binding Mapping(required=[input, options])

Attributes:	input : enum(‘radio’) options : List(string) element : string

altair.binding_range(self, input=Undefined, element=Undefined, max=Undefined, min=Undefined, step=Undefined, **kwds)¶

A range binding Mapping(required=[input])

Attributes:	input : enum(‘range’) element : string max : float min : float step : float

altair.binding_select(self, input=Undefined, options=Undefined, element=Undefined, **kwds)¶

A select binding Mapping(required=[input, options])

Attributes:	input : enum(‘select’) options : List(string) element : string

altair.condition(predicate, if_true, if_false, **kwargs)¶

A conditional attribute or encoding

Parameters:

predicate: NamedSelection, LogicalOperandPredicate, expr.Expression, dict, or string: the selection predicate or test predicate for the condition. if a string is passed, it will be treated as a test operand.
if_true:: the spec or object to use if the selection predicate is true
if_false:: the spec or object to use if the selection predicate is false
**kwargs:: additional keyword args are added to the resulting dict

Returns:

spec: dict or VegaLiteSchema: the spec that describes the condition

altair.hconcat(*charts, **kwargs)¶: Concatenate charts horizontally

altair.layer(*charts, **kwargs)¶: layer multiple charts

altair.list_datasets()¶: List the available datasets.

altair.load_dataset(name)¶: Load a dataset by name as a pandas.DataFrame.

altair.load_schema()¶: Load the json schema associated with this module’s functions

altair.parse_shorthand(shorthand, data=None, parse_aggregates=True, parse_window_ops=False, parse_timeunits=True, parse_types=True)¶

General tool to parse shorthand values

These are of the form:

“col_name”
“col_name:O”
“average(col_name)”
“average(col_name):O”

Optionally, a dataframe may be supplied, from which the type will be inferred if not specified in the shorthand.

Parameters:

shorthand : dict or string: The shorthand representation to be parsed
data : DataFrame, optional: If specified and of type DataFrame, then use these values to infer the column type if not provided by the shorthand.
parse_aggregates : boolean: If True (default), then parse aggregate functions within the shorthand.
parse_window_ops : boolean: If True then parse window operations within the shorthand (default:False)
parse_timeunits : boolean: If True (default), then parse timeUnits from within the shorthand
parse_types : boolean: If True (default), then parse typecodes within the shorthand

Returns:

attrs : dict: a dictionary of attributes extracted from the shorthand

Examples

>>> data = pd.DataFrame({'foo': ['A', 'B', 'A', 'B'],
...                      'bar': [1, 2, 3, 4]})

>>> parse_shorthand('name') == {'field': 'name'}
True

>> parse_shorthand(‘name:Q’) == {‘field’: ‘name’, ‘type’: ‘quantitative’} True

>>> parse_shorthand('average(col)') == {'aggregate': 'average', 'field': 'col'}
True

>>> parse_shorthand('foo:O') == {'field': 'foo', 'type': 'ordinal'}
True

>>> parse_shorthand('min(foo):Q') == {'aggregate': 'min', 'field': 'foo', 'type': 'quantitative'}
True

>>> parse_shorthand('month(col)') == {'field': 'col', 'timeUnit': 'month', 'type': 'temporal'}
True

>>> parse_shorthand('year(col):O') == {'field': 'col', 'timeUnit': 'year', 'type': 'ordinal'}
True

>>> parse_shorthand('foo', data) == {'field': 'foo', 'type': 'nominal'}
True

>>> parse_shorthand('bar', data) == {'field': 'bar', 'type': 'quantitative'}
True

>>> parse_shorthand('bar:O', data) == {'field': 'bar', 'type': 'ordinal'}
True

>>> parse_shorthand('sum(bar)', data) == {'aggregate': 'sum', 'field': 'bar', 'type': 'quantitative'}
True

>>> parse_shorthand('count()', data) == {'aggregate': 'count', 'type': 'quantitative'}
True

altair.pipe(data, *funcs)¶

Pipe a value through a sequence of functions

I.e. pipe(data, f, g, h) is equivalent to h(g(f(data)))

We think of the value as progressing through a pipe of several transformations, much like pipes in UNIX

$ cat data | f | g | h

>>> double = lambda i: 2 * i
>>> pipe(3, double, str)
'6'

See Also:: compose thread_first thread_last

altair.repeat(repeater)¶

Tie a channel to the row or column within a repeated chart

The output of this should be passed to the field attribute of a channel.

Parameters:	repeater : {‘row’\|’column’} The repeater to tie the field to.
Returns:	repeat : RepeatRef object

altair.selection(name=None, type=Undefined, **kwds)¶

Create a named selection.

Parameters:	name : string (optional) The name of the selection. If not specified, a unique name will be created. type : string The type of the selection: one of [“interval”, “single”, or “multi”] **kwds : additional keywords will be used to construct a SelectionDef instance that controls the selection.
Returns:	selection: NamedSelection The selection object that can be used in chart creation.

altair.selection_interval(self, type=Undefined, bind=Undefined, empty=Undefined, encodings=Undefined, fields=Undefined, mark=Undefined, on=Undefined, resolve=Undefined, translate=Undefined, zoom=Undefined, **kwds)¶

Create a selection with type=’interval’ Mapping(required=[type])

Attributes:

type : enum(‘interval’)

bind : enum(‘scales’)

Establishes a two-way binding between the interval selection and the scales used within the same view. This allows a user to interactively pan and zoom the view.

empty : enum(‘all’, ‘none’)

By default, all data values are considered to lie within an empty selection. When set to none, empty selections contain no data values.

encodings : List(SingleDefChannel)

An array of encoding channels. The corresponding data field values must match for a data tuple to fall within the selection.

fields : List(string)

An array of field names whose values must match for a data tuple to fall within the selection.

mark : BrushConfig

An interval selection also adds a rectangle mark to depict the extents of the interval. The mark property can be used to customize the appearance of the mark.

on : VgEventStream

A Vega event stream (object or selector) that triggers the selection. For interval selections, the event stream must specify a start and end.

resolve : SelectionResolution

With layered and multi-view displays, a strategy that determines how selections’ data queries are resolved when applied in a filter transform, conditional encoding rule, or scale domain.

translate : anyOf(string, boolean)

When truthy, allows a user to interactively move an interval selection back-and-forth. Can be true, false (to disable panning), or a Vega event stream definition which must include a start and end event to trigger continuous panning.

Default value: true, which corresponds to [mousedown, window:mouseup] > window:mousemove! which corresponds to clicks and dragging within an interval selection to reposition it.

zoom : anyOf(string, boolean)

When truthy, allows a user to interactively resize an interval selection. Can be true, false (to disable zooming), or a Vega event stream definition. Currently, only wheel events are supported.

Default value: true, which corresponds to wheel!.

altair.selection_multi(self, type=Undefined, empty=Undefined, encodings=Undefined, fields=Undefined, nearest=Undefined, on=Undefined, resolve=Undefined, toggle=Undefined, **kwds)¶

Create a selection with type=’multi’ Mapping(required=[type])

Attributes:

type : enum(‘multi’)

empty : enum(‘all’, ‘none’)

By default, all data values are considered to lie within an empty selection. When set to none, empty selections contain no data values.

encodings : List(SingleDefChannel)

An array of encoding channels. The corresponding data field values must match for a data tuple to fall within the selection.

fields : List(string)

An array of field names whose values must match for a data tuple to fall within the selection.

nearest : boolean

When true, an invisible voronoi diagram is computed to accelerate discrete selection. The data value nearest the mouse cursor is added to the selection.

See the nearest transform documentation for more information.

on : VgEventStream

A Vega event stream (object or selector) that triggers the selection. For interval selections, the event stream must specify a start and end.

resolve : SelectionResolution

With layered and multi-view displays, a strategy that determines how selections’ data queries are resolved when applied in a filter transform, conditional encoding rule, or scale domain.

toggle : anyOf(string, boolean)

Controls whether data values should be toggled or only ever inserted into multi selections. Can be true, false (for insertion only), or a Vega expression.

Default value: true, which corresponds to event.shiftKey (i.e., data values are toggled when a user interacts with the shift-key pressed).

See the toggle transform documentation for more information.

altair.selection_single(self, type=Undefined, bind=Undefined, empty=Undefined, encodings=Undefined, fields=Undefined, nearest=Undefined, on=Undefined, resolve=Undefined, **kwds)¶

Create a selection with type=’single’ Mapping(required=[type])

Attributes:

type : enum(‘single’)

bind : anyOf(VgBinding, Mapping(required=[]))

Establish a two-way binding between a single selection and input elements (also known as dynamic query widgets). A binding takes the form of Vega’s input element binding definition or can be a mapping between projected field/encodings and binding definitions.

See the bind transform documentation for more information.

empty : enum(‘all’, ‘none’)

By default, all data values are considered to lie within an empty selection. When set to none, empty selections contain no data values.

encodings : List(SingleDefChannel)

An array of encoding channels. The corresponding data field values must match for a data tuple to fall within the selection.

fields : List(string)

An array of field names whose values must match for a data tuple to fall within the selection.

nearest : boolean

When true, an invisible voronoi diagram is computed to accelerate discrete selection. The data value nearest the mouse cursor is added to the selection.

See the nearest transform documentation for more information.

on : VgEventStream

A Vega event stream (object or selector) that triggers the selection. For interval selections, the event stream must specify a start and end.

resolve : SelectionResolution

With layered and multi-view displays, a strategy that determines how selections’ data queries are resolved when applied in a filter transform, conditional encoding rule, or scale domain.

altair.topo_feature(url, feature, **kwargs)¶

A convenience function for extracting features from a topojson url

Parameters:

url : string: An URL from which to load the data set.
feature : string: The name of the TopoJSON object set to convert to a GeoJSON feature collection. For example, in a map of the world, there may be an object set named “countries”. Using the feature property, we can extract this set and generate a GeoJSON feature object for each country.
**kwargs :: additional keywords passed to TopoDataFormat

altair.value(value, **kwargs)¶: Specify a value for use in an encoding

altair.vconcat(*charts, **kwargs)¶: Concatenate charts vertically

altair.limit_rows¶

Raise MaxRowsError if the data model has more than max_rows.

If max_rows is None, then do not perform any check.

altair.sample¶: Reduce the size of the data model by sampling without replacement.

altair.to_csv¶: Write the data model to a .csv file and return a url based data model.

altair.to_json¶: Write the data model to a .json file and return a url based data model.

altair.to_values¶: Replace a DataFrame by a data model with values.

Vega Expressions¶

Tools for creating transform & filter expressions with a python syntax

class altair.expr.Expression(*args, **kwds)¶

Base object for enabling build-up of Javascript expressions using a Python syntax. Calling repr(obj) will return a Javascript representation of the object and the operations it encodes.

to_dict(*args, **kwargs)¶

Return a dictionary representation of the object

Parameters:	validate : boolean or string If True (default), then validate the output dictionary against the schema. If “deep” then recursively validate all objects in the spec. This takes much more time, but it results in friendlier tracebacks for large objects. ignore : list A list of keys to ignore. This will not passed to child to_dict function calls. context : dict (optional) A context dictionary that will be passed to all child to_dict function calls
Returns:	dct : dictionary The dictionary representation of this object
Raises:	jsonschema.ValidationError : if validate=True and the dict does not conform to the schema