altair.TopLevelUnitSpec

class altair.TopLevelUnitSpec(data=Undefined, mark=Undefined, autosize=Undefined, background=Undefined, bounds=Undefined, config=Undefined, datasets=Undefined, description=Undefined, encoding=Undefined, height=Undefined, name=Undefined, padding=Undefined, projection=Undefined, resolve=Undefined, selection=Undefined, title=Undefined, transform=Undefined, usermeta=Undefined, view=Undefined, width=Undefined, **kwds)

TopLevelUnitSpec schema wrapper

Mapping(required=[data, mark])

Attributes:
data : anyOf(Data, None)

An object describing the data source. Set to null to ignore the parent’s data source. If no data is set, it is derived from the parent.

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)

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.

Default value : pad

background : Color

CSS color property to use as the background of the entire view.

Default value: "white"

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"

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 : FacetedEncoding

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

height : anyOf(float, enum(‘container’), Step)

The height of a visualization.

  • For a plot with a continuous y-field, height should be a number.
  • For a plot with either a discrete y-field or no y-field, height can be either a number indicating a fixed height or an object in the form of {step: number} defining the height per discrete step. (No y-field is equivalent to having one discrete step.)
  • To enable responsive sizing on height, it should be set to "container".

Default value: Based on config.view.continuousHeight for a plot with a continuous y-field and config.view.discreteHeight otherwise.

Note: For plots with row and column channels, this represents the height of a single view and the "container" option cannot be used.

See also: height documentation.

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.

resolve : Resolve

Scale, axis, and legend resolutions for view composition specifications.

selection : Mapping(required=[])

A key-value mapping between selection names and definitions.

title : anyOf(Text, TitleParams)

Title for the plot.

transform : List(Transform)

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

usermeta : Mapping(required=[])

Optional metadata that will be passed to Vega. This object is completely ignored by Vega and Vega-Lite and can be used for custom metadata.

view : ViewBackground

An object defining the view background’s fill and stroke.

Default value: none (transparent)

width : anyOf(float, enum(‘container’), Step)

The width of a visualization.

  • For a plot with a continuous x-field, width should be a number.
  • For a plot with either a discrete x-field or no x-field, width can be either a number indicating a fixed width or an object in the form of {step: number} defining the width per discrete step. (No x-field is equivalent to having one discrete step.)
  • To enable responsive sizing on width, it should be set to "container".

Default value: Based on config.view.continuousWidth for a plot with a continuous x-field and config.view.discreteWidth otherwise.

Note: For plots with row and column channels, this represents the width of a single view and the "container" option cannot be used.

See also: width documentation.

$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/v4.json. Setting the $schema property allows automatic validation and autocomplete in editors that support JSON schema.

__init__(data=Undefined, mark=Undefined, autosize=Undefined, background=Undefined, bounds=Undefined, config=Undefined, datasets=Undefined, description=Undefined, encoding=Undefined, height=Undefined, name=Undefined, padding=Undefined, projection=Undefined, resolve=Undefined, selection=Undefined, title=Undefined, transform=Undefined, usermeta=Undefined, view=Undefined, width=Undefined, **kwds)

Methods

__init__([data, mark, autosize, background, …])
copy([deep, ignore]) Return a copy of the object
from_dict(dct[, validate, _wrapper_classes]) Construct class from a dictionary representation
from_json(json_string[, validate]) Instantiate the object from a valid JSON string
resolve_references([schema]) Resolve references in the context of this object’s schema or root schema.
to_dict([validate, ignore, context]) Return a dictionary representation of the object
to_json([validate, ignore, context, indent, …]) Emit the JSON representation for this object as a string.
validate(instance[, schema]) Validate the instance against the class schema in the context of the rootschema.
validate_property(name, value[, schema]) Validate a property against property schema in the context of the
copy(deep=True, ignore=())

Return a copy of the object

Parameters:
deep : boolean or list, optional

If True (default) then return a deep copy of all dict, list, and SchemaBase objects within the object structure. If False, then only copy the top object. If a list or iterable, then only copy the listed attributes.

ignore : list, optional

A list of keys for which the contents should not be copied, but only stored by reference.

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

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.

resolve_references(schema=None)

Resolve references in the context of this object’s schema or root schema.

to_dict(validate=True, ignore=None, context=None)

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.

validate(instance, schema=None)

Validate the instance against the class schema in the context of the rootschema.

validate_property(name, value, schema=None)

Validate a property against property schema in the context of the rootschema