expressions#

Represent array expressions to be computed on the client (browser) side by BokehJS.

Expression models are useful as DataSpec values when it is desired that the array values be computed in the browser:

p.circle(x={'expr': some_expression}, ...)

or using the expr convenience function:

from bokeh.core.properties import expr

p.circle(x=expr(some_expression), ...)

In this case, the values of the x coordinates will be computed in the browser by the JavaScript implementation of some_expression using a ColumnDataSource as input.

class CumSum(*args: Any, id: ID | None = None, **kwargs: Any)[source]#

Bases: Expression

An expression for generating arrays by cumulatively summing a single column from a ColumnDataSource.

JSON Prototype
{
  "id": "p118521",
  "include_zero": false,
  "js_event_callbacks": {
    "type": "map"
  },
  "js_property_callbacks": {
    "type": "map"
  },
  "name": null,
  "subscribed_events": {
    "type": "set"
  },
  "syncable": true,
  "tags": []
}

Public Data Attributes:

field

The name of a ColumnDataSource column to cumulatively sum for new values.

include_zero

Whether to include zero at the start of the result.

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

id

subscribed_events

Collection of events that are subscribed to by Python callbacks.

Inherited from Expression

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

id

subscribed_events

Collection of events that are subscribed to by Python callbacks.

Inherited from Model

id

ref

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

js_event_callbacks

A mapping of event names to lists of CustomJS callbacks.

js_property_callbacks

A mapping of attribute names to lists of CustomJS callbacks, to be set up on BokehJS side when the document is created.

subscribed_events

Collection of events that are subscribed to by Python callbacks.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

Inherited from HasDocumentRef

document

The Document this model is attached to (can be None)

Inherited from PropertyCallbackManager

document

Inherited from EventCallbackManager

document

id

subscribed_events

Public Methods:

__init__(*[, include_zero, name, syncable, tags])

Inherited from Expression

__init__(*[, syncable, tags])

Inherited from Model

__init_subclass__()

This method is called when a class is subclassed.

__new__(cls, *args[, id])

__init__(*args, **kwargs)

__str__()

Return str(self).

__repr__()

Return repr(self).

destroy()

Clean up references to the document and property

parameters()

Generate Python Parameter values suitable for functions that are derived from the glyph.

js_on_event(event, *callbacks)

js_link(attr, other, other_attr[, attr_selector])

Link two Bokeh model properties using JavaScript.

js_on_change(event, *callbacks)

Attach a CustomJS callback to an arbitrary BokehJS model event.

on_change(attr, *callbacks)

Add a callback on this object to trigger when attr changes.

references()

Returns all Models that this object has references to.

select(selector)

Query this object and all of its references for objects that match the given selector.

select_one(selector)

Query this object and all of its references for objects that match the given selector.

set_select(selector, updates)

Update objects that match a given selector with the specified attribute/value updates.

to_serializable(serializer)

Converts this object to a serializable representation.

trigger(attr, old, new[, hint, setter])

Inherited from HasProps

__init_subclass__()

This method is called when a class is subclassed.

__init__(**properties)

__setattr__(name, value)

Intercept attribute setting on HasProps in order to special case a few situations:

__getattr__(name)

Intercept attribute setting on HasProps in order to special case a few situations:

__str__()

Return str(self).

__repr__()

Return repr(self).

equals(other)

Structural equality of models.

to_serializable(serializer)

Converts this object to a serializable representation.

set_from_json(name, value, *[, setter])

Set a property value on this object from JSON.

update(**kwargs)

Updates the object's properties from the given keyword arguments.

lookup()

Find the PropertyDescriptor for a Bokeh property on a class, given the property name.

properties()

Collect the names of properties on this class.

descriptors()

List of property descriptors in the order of definition.

properties_with_refs()

Collect the names of all properties on this class that also have references.

dataspecs()

Collect the names of all DataSpec properties on this class.

properties_with_values(*[, ...])

Collect a dict mapping property names to their values.

query_properties_with_values(query, *[, ...])

Query the properties values of HasProps instances with a predicate.

themed_values()

Get any theme-provided overrides.

apply_theme(property_values)

Apply a set of theme values which will be used rather than defaults, but will not override application-set values.

unapply_theme()

Remove any themed values and restore defaults.

Inherited from Serializable

to_serializable(serializer)

Converts this object to a serializable representation.

Inherited from HasDocumentRef

__init__(*args, **kw)

Inherited from PropertyCallbackManager

__init__(*args, **kw)

on_change(attr, *callbacks)

Add a callback on this object to trigger when attr changes.

remove_on_change(attr, *callbacks)

Remove a callback from this object

trigger(attr, old, new[, hint, setter])

Trigger callbacks for attr on this object.

Inherited from EventCallbackManager

__init__(*args, **kw)

on_event(event, *callbacks)

Run callbacks when the specified event occurs on this Model


field = Undefined#
Type:

Required(String)

The name of a ColumnDataSource column to cumulatively sum for new values.

include_zero = False#
Type:

Bool

Whether to include zero at the start of the result. Note that the length of the result is always the same as the input column. Therefore if this property is True, then the last value of the column will not be included in the sum.

source = ColumnDataSource(data=dict(foo=[1, 2, 3, 4]))

CumSum(field='foo')
# -> [1, 3, 6, 10]

CumSum(field='foo', include_zero=True)
# -> [0, 1, 3, 6]
name = None#
Type:

Nullable(String)

An arbitrary, user-supplied name for this model.

This name can be useful when querying the document to retrieve specific Bokeh models.

>>> plot.circle([1,2,3], [4,5,6], name="temp")
>>> plot.select(name="temp")
[GlyphRenderer(id='399d53f5-73e9-44d9-9527-544b761c7705', ...)]

Note

No uniqueness guarantees or other conditions are enforced on any names that are provided, nor is the name used directly by Bokeh for any reason.

syncable = True#
Type:

Bool

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser. Setting to False may be useful to reduce network traffic when dealing with frequently updated objects whose updated values we don’t need.

Note

Setting this property to False will prevent any on_change() callbacks on this object from triggering. However, any JS-side callbacks will still work.

tags = []#
Type:

List

An optional list of arbitrary, user-supplied values to attach to this model.

This data can be useful when querying the document to retrieve specific Bokeh models:

>>> r = plot.circle([1,2,3], [4,5,6])
>>> r.tags = ["foo", 10]
>>> plot.select(tags=['foo', 10])
[GlyphRenderer(id='1de4c3df-a83d-480a-899b-fb263d3d5dd9', ...)]

Or simply a convenient way to attach any necessary metadata to a model that can be accessed by CustomJS callbacks, etc.

Note

No uniqueness guarantees or other conditions are enforced on any tags that are provided, nor are the tags used directly by Bokeh for any reason.

apply_theme(property_values: dict[str, Any]) None#

Apply a set of theme values which will be used rather than defaults, but will not override application-set values.

The passed-in dictionary may be kept around as-is and shared with other instances to save memory (so neither the caller nor the HasProps instance should modify it).

Parameters:

property_values (dict) – theme values to use in place of defaults

Returns:

None

classmethod dataspecs() dict[str, DataSpec]#

Collect the names of all DataSpec properties on this class.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Returns:

names of DataSpec properties

Return type:

set[str]

classmethod descriptors() list[PropertyDescriptor[Any]]#

List of property descriptors in the order of definition.

destroy() None#

Clean up references to the document and property

equals(other: HasProps) bool#

Structural equality of models.

Parameters:

other (HasProps) – the other instance to compare to

Returns:

True, if properties are structurally equal, otherwise False

Link two Bokeh model properties using JavaScript.

This is a convenience method that simplifies adding a CustomJS callback to update one Bokeh model property whenever another changes value.

Parameters:
  • attr (str) – The name of a Bokeh property on this model

  • other (Model) – A Bokeh model to link to self.attr

  • other_attr (str) – The property on other to link together

  • attr_selector (Union[int, str]) – The index to link an item in a subscriptable attr

Added in version 1.1

Raises:

ValueError

Examples

This code with js_link:

select.js_link('value', plot, 'sizing_mode')

is equivalent to the following:

from bokeh.models import CustomJS
select.js_on_change('value',
    CustomJS(args=dict(other=plot),
             code="other.sizing_mode = this.value"
    )
)

Additionally, to use attr_selector to attach the left side of a range slider to a plot’s x_range:

range_slider.js_link('value', plot.x_range, 'start', attr_selector=0)

which is equivalent to:

from bokeh.models import CustomJS
range_slider.js_on_change('value',
    CustomJS(args=dict(other=plot.x_range),
             code="other.start = this.value[0]"
    )
)
js_on_change(event: str, *callbacks: JSEventCallback) None#

Attach a CustomJS callback to an arbitrary BokehJS model event.

On the BokehJS side, change events for model properties have the form "change:property_name". As a convenience, if the event name passed to this method is also the name of a property on the model, then it will be prefixed with "change:" automatically:

# these two are equivalent
source.js_on_change('data', callback)
source.js_on_change('change:data', callback)

However, there are other kinds of events that can be useful to respond to, in addition to property change events. For example to run a callback whenever data is streamed to a ColumnDataSource, use the "stream" event on the source:

source.js_on_change('streaming', callback)
classmethod lookup(name: str, *, raises: bool = True) PropertyDescriptor[Any] | None#

Find the PropertyDescriptor for a Bokeh property on a class, given the property name.

Parameters:
  • name (str) – name of the property to search for

  • raises (bool) – whether to raise or return None if missing

Returns:

descriptor for property named name

Return type:

PropertyDescriptor

on_change(attr: str, *callbacks: PropertyCallback) None#

Add a callback on this object to trigger when attr changes.

Parameters:
  • attr (str) – an attribute name on this object

  • *callbacks (callable) – callback functions to register

Returns:

None

Example:

widget.on_change('value', callback1, callback2, ..., callback_n)
on_event(event: str | type[Event], *callbacks: EventCallback) None#

Run callbacks when the specified event occurs on this Model

Not all Events are supported for all Models. See specific Events in bokeh.events for more information on which Models are able to trigger them.

classmethod parameters() list[Parameter]#

Generate Python Parameter values suitable for functions that are derived from the glyph.

Returns:

list(Parameter)

classmethod properties(*, _with_props: bool = False) set[str] | dict[str, Property[Any]]#

Collect the names of properties on this class.

Warning

In a future version of Bokeh, this method will return a dictionary mapping property names to property objects. To future-proof this current usage of this method, wrap the return value in list.

Returns:

property names

classmethod properties_with_refs() dict[str, Property[Any]]#

Collect the names of all properties on this class that also have references.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Returns:

names of properties that have references

Return type:

set[str]

properties_with_values(*, include_defaults: bool = True, include_undefined: bool = False) dict[str, Any]#

Collect a dict mapping property names to their values.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Non-serializable properties are skipped and property values are in “serialized” format which may be slightly different from the values you would normally read from the properties; the intent of this method is to return the information needed to losslessly reconstitute the object instance.

Parameters:

include_defaults (bool, optional) – Whether to include properties that haven’t been explicitly set since the object was created. (default: True)

Returns:

mapping from property names to their values

Return type:

dict

query_properties_with_values(query: Callable[[PropertyDescriptor[Any]], bool], *, include_defaults: bool = True, include_undefined: bool = False) dict[str, Any]#

Query the properties values of HasProps instances with a predicate.

Parameters:
  • query (callable) – A callable that accepts property descriptors and returns True or False

  • include_defaults (bool, optional) – Whether to include properties that have not been explicitly set by a user (default: True)

Returns:

mapping of property names and values for matching properties

Return type:

dict

references() set[Model]#

Returns all Models that this object has references to.

remove_on_change(attr: str, *callbacks: Callable[[str, Any, Any], None]) None#

Remove a callback from this object

select(selector: SelectorType) Iterable[Model]#

Query this object and all of its references for objects that match the given selector.

Parameters:

selector (JSON-like) –

Returns:

seq[Model]

select_one(selector: SelectorType) Model | None#

Query this object and all of its references for objects that match the given selector. Raises an error if more than one object is found. Returns single matching object, or None if nothing is found :param selector: :type selector: JSON-like

Returns:

Model

set_from_json(name: str, value: Any, *, setter: Setter | None = None) None#

Set a property value on this object from JSON.

Parameters:
  • name – (str) : name of the attribute to set

  • json – (JSON-value) : value to set to the attribute to

  • models (dict or None, optional) –

    Mapping of model ids to models (default: None)

    This is needed in cases where the attributes to update also have values that have references.

  • setter (ClientSession or ServerSession or None, optional) –

    This is used to prevent “boomerang” updates to Bokeh apps.

    In the context of a Bokeh server application, incoming updates to properties will be annotated with the session that is doing the updating. This value is propagated through any subsequent change notifications that the update triggers. The session can compare the event setter to itself, and suppress any updates that originate from itself.

Returns:

None

set_select(selector: type[Model] | SelectorType, updates: dict[str, Any]) None#

Update objects that match a given selector with the specified attribute/value updates.

Parameters:
  • selector (JSON-like) –

  • updates (dict) –

Returns:

None

themed_values() dict[str, Any] | None#

Get any theme-provided overrides.

Results are returned as a dict from property name to value, or None if no theme overrides any values for this instance.

Returns:

dict or None

to_serializable(serializer: Serializer) ObjectRefRep#

Converts this object to a serializable representation.

trigger(attr: str, old: Any, new: Any, hint: DocumentPatchedEvent | None = None, setter: Setter | None = None) None#
unapply_theme() None#

Remove any themed values and restore defaults.

Returns:

None

update(**kwargs: Any) None#

Updates the object’s properties from the given keyword arguments.

Returns:

None

Examples

The following are equivalent:

from bokeh.models import Range1d

r = Range1d

# set properties individually:
r.start = 10
r.end = 20

# update properties together:
r.update(start=10, end=20)
property document: Document | None#

The Document this model is attached to (can be None)

class CustomJSExpr(*args: Any, id: ID | None = None, **kwargs: Any)[source]#

Bases: Expression

Evaluate a JavaScript function/generator.

Warning

The explicit purpose of this Bokeh Model is to embed raw JavaScript code for a browser to execute. If any part of the code is derived from untrusted user inputs, then you must take appropriate care to sanitize the user input prior to passing to Bokeh.

JSON Prototype
{
  "args": {
    "type": "map"
  },
  "code": "",
  "id": "p118527",
  "js_event_callbacks": {
    "type": "map"
  },
  "js_property_callbacks": {
    "type": "map"
  },
  "name": null,
  "subscribed_events": {
    "type": "set"
  },
  "syncable": true,
  "tags": []
}

Public Data Attributes:

args

A mapping of names to Python objects.

code

A snippet of JavaScript code to execute in the browser.

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

id

subscribed_events

Collection of events that are subscribed to by Python callbacks.

Inherited from Expression

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

id

subscribed_events

Collection of events that are subscribed to by Python callbacks.

Inherited from Model

id

ref

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

js_event_callbacks

A mapping of event names to lists of CustomJS callbacks.

js_property_callbacks

A mapping of attribute names to lists of CustomJS callbacks, to be set up on BokehJS side when the document is created.

subscribed_events

Collection of events that are subscribed to by Python callbacks.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

Inherited from HasDocumentRef

document

The Document this model is attached to (can be None)

Inherited from PropertyCallbackManager

document

Inherited from EventCallbackManager

document

id

subscribed_events

Public Methods:

__init__(*[, code, name, syncable, tags])

Inherited from Expression

__init__(*[, syncable, tags])

Inherited from Model

__init_subclass__()

This method is called when a class is subclassed.

__new__(cls, *args[, id])

__init__(*args, **kwargs)

__str__()

Return str(self).

__repr__()

Return repr(self).

destroy()

Clean up references to the document and property

parameters()

Generate Python Parameter values suitable for functions that are derived from the glyph.

js_on_event(event, *callbacks)

js_link(attr, other, other_attr[, attr_selector])

Link two Bokeh model properties using JavaScript.

js_on_change(event, *callbacks)

Attach a CustomJS callback to an arbitrary BokehJS model event.

on_change(attr, *callbacks)

Add a callback on this object to trigger when attr changes.

references()

Returns all Models that this object has references to.

select(selector)

Query this object and all of its references for objects that match the given selector.

select_one(selector)

Query this object and all of its references for objects that match the given selector.

set_select(selector, updates)

Update objects that match a given selector with the specified attribute/value updates.

to_serializable(serializer)

Converts this object to a serializable representation.

trigger(attr, old, new[, hint, setter])

Inherited from HasProps

__init_subclass__()

This method is called when a class is subclassed.

__init__(**properties)

__setattr__(name, value)

Intercept attribute setting on HasProps in order to special case a few situations:

__getattr__(name)

Intercept attribute setting on HasProps in order to special case a few situations:

__str__()

Return str(self).

__repr__()

Return repr(self).

equals(other)

Structural equality of models.

to_serializable(serializer)

Converts this object to a serializable representation.

set_from_json(name, value, *[, setter])

Set a property value on this object from JSON.

update(**kwargs)

Updates the object's properties from the given keyword arguments.

lookup()

Find the PropertyDescriptor for a Bokeh property on a class, given the property name.

properties()

Collect the names of properties on this class.

descriptors()

List of property descriptors in the order of definition.

properties_with_refs()

Collect the names of all properties on this class that also have references.

dataspecs()

Collect the names of all DataSpec properties on this class.

properties_with_values(*[, ...])

Collect a dict mapping property names to their values.

query_properties_with_values(query, *[, ...])

Query the properties values of HasProps instances with a predicate.

themed_values()

Get any theme-provided overrides.

apply_theme(property_values)

Apply a set of theme values which will be used rather than defaults, but will not override application-set values.

unapply_theme()

Remove any themed values and restore defaults.

Inherited from Serializable

to_serializable(serializer)

Converts this object to a serializable representation.

Inherited from HasDocumentRef

__init__(*args, **kw)

Inherited from PropertyCallbackManager

__init__(*args, **kw)

on_change(attr, *callbacks)

Add a callback on this object to trigger when attr changes.

remove_on_change(attr, *callbacks)

Remove a callback from this object

trigger(attr, old, new[, hint, setter])

Trigger callbacks for attr on this object.

Inherited from EventCallbackManager

__init__(*args, **kw)

on_event(event, *callbacks)

Run callbacks when the specified event occurs on this Model


args = {}#
Type:

Dict(String, AnyRef)

A mapping of names to Python objects. In particular those can be bokeh’s models. These objects are made available to the callback’s code snippet as the values of named parameters to the callback. There is no need to manually include the data source of the associated glyph renderer, as it is available within the scope of the code via this keyword (e.g. this.data will give access to raw data).

code = ''#
Type:

String

A snippet of JavaScript code to execute in the browser. The code is made into the body of a generator function, and all of of the named objects in args are available as parameters that the code can use. One can either return an array-like object (array, typed array, nd-array), an iterable (which will be converted to an array) or a scalar value (which will be converted into an array of an appropriate length), or alternatively yield values that will be collected into an array.

name = None#
Type:

Nullable(String)

An arbitrary, user-supplied name for this model.

This name can be useful when querying the document to retrieve specific Bokeh models.

>>> plot.circle([1,2,3], [4,5,6], name="temp")
>>> plot.select(name="temp")
[GlyphRenderer(id='399d53f5-73e9-44d9-9527-544b761c7705', ...)]

Note

No uniqueness guarantees or other conditions are enforced on any names that are provided, nor is the name used directly by Bokeh for any reason.

syncable = True#
Type:

Bool

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser. Setting to False may be useful to reduce network traffic when dealing with frequently updated objects whose updated values we don’t need.

Note

Setting this property to False will prevent any on_change() callbacks on this object from triggering. However, any JS-side callbacks will still work.

tags = []#
Type:

List

An optional list of arbitrary, user-supplied values to attach to this model.

This data can be useful when querying the document to retrieve specific Bokeh models:

>>> r = plot.circle([1,2,3], [4,5,6])
>>> r.tags = ["foo", 10]
>>> plot.select(tags=['foo', 10])
[GlyphRenderer(id='1de4c3df-a83d-480a-899b-fb263d3d5dd9', ...)]

Or simply a convenient way to attach any necessary metadata to a model that can be accessed by CustomJS callbacks, etc.

Note

No uniqueness guarantees or other conditions are enforced on any tags that are provided, nor are the tags used directly by Bokeh for any reason.

apply_theme(property_values: dict[str, Any]) None#

Apply a set of theme values which will be used rather than defaults, but will not override application-set values.

The passed-in dictionary may be kept around as-is and shared with other instances to save memory (so neither the caller nor the HasProps instance should modify it).

Parameters:

property_values (dict) – theme values to use in place of defaults

Returns:

None

classmethod dataspecs() dict[str, DataSpec]#

Collect the names of all DataSpec properties on this class.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Returns:

names of DataSpec properties

Return type:

set[str]

classmethod descriptors() list[PropertyDescriptor[Any]]#

List of property descriptors in the order of definition.

destroy() None#

Clean up references to the document and property

equals(other: HasProps) bool#

Structural equality of models.

Parameters:

other (HasProps) – the other instance to compare to

Returns:

True, if properties are structurally equal, otherwise False

Link two Bokeh model properties using JavaScript.

This is a convenience method that simplifies adding a CustomJS callback to update one Bokeh model property whenever another changes value.

Parameters:
  • attr (str) – The name of a Bokeh property on this model

  • other (Model) – A Bokeh model to link to self.attr

  • other_attr (str) – The property on other to link together

  • attr_selector (Union[int, str]) – The index to link an item in a subscriptable attr

Added in version 1.1

Raises:

ValueError

Examples

This code with js_link:

select.js_link('value', plot, 'sizing_mode')

is equivalent to the following:

from bokeh.models import CustomJS
select.js_on_change('value',
    CustomJS(args=dict(other=plot),
             code="other.sizing_mode = this.value"
    )
)

Additionally, to use attr_selector to attach the left side of a range slider to a plot’s x_range:

range_slider.js_link('value', plot.x_range, 'start', attr_selector=0)

which is equivalent to:

from bokeh.models import CustomJS
range_slider.js_on_change('value',
    CustomJS(args=dict(other=plot.x_range),
             code="other.start = this.value[0]"
    )
)
js_on_change(event: str, *callbacks: JSEventCallback) None#

Attach a CustomJS callback to an arbitrary BokehJS model event.

On the BokehJS side, change events for model properties have the form "change:property_name". As a convenience, if the event name passed to this method is also the name of a property on the model, then it will be prefixed with "change:" automatically:

# these two are equivalent
source.js_on_change('data', callback)
source.js_on_change('change:data', callback)

However, there are other kinds of events that can be useful to respond to, in addition to property change events. For example to run a callback whenever data is streamed to a ColumnDataSource, use the "stream" event on the source:

source.js_on_change('streaming', callback)
classmethod lookup(name: str, *, raises: bool = True) PropertyDescriptor[Any] | None#

Find the PropertyDescriptor for a Bokeh property on a class, given the property name.

Parameters:
  • name (str) – name of the property to search for

  • raises (bool) – whether to raise or return None if missing

Returns:

descriptor for property named name

Return type:

PropertyDescriptor

on_change(attr: str, *callbacks: PropertyCallback) None#

Add a callback on this object to trigger when attr changes.

Parameters:
  • attr (str) – an attribute name on this object

  • *callbacks (callable) – callback functions to register

Returns:

None

Example:

widget.on_change('value', callback1, callback2, ..., callback_n)
on_event(event: str | type[Event], *callbacks: EventCallback) None#

Run callbacks when the specified event occurs on this Model

Not all Events are supported for all Models. See specific Events in bokeh.events for more information on which Models are able to trigger them.

classmethod parameters() list[Parameter]#

Generate Python Parameter values suitable for functions that are derived from the glyph.

Returns:

list(Parameter)

classmethod properties(*, _with_props: bool = False) set[str] | dict[str, Property[Any]]#

Collect the names of properties on this class.

Warning

In a future version of Bokeh, this method will return a dictionary mapping property names to property objects. To future-proof this current usage of this method, wrap the return value in list.

Returns:

property names

classmethod properties_with_refs() dict[str, Property[Any]]#

Collect the names of all properties on this class that also have references.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Returns:

names of properties that have references

Return type:

set[str]

properties_with_values(*, include_defaults: bool = True, include_undefined: bool = False) dict[str, Any]#

Collect a dict mapping property names to their values.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Non-serializable properties are skipped and property values are in “serialized” format which may be slightly different from the values you would normally read from the properties; the intent of this method is to return the information needed to losslessly reconstitute the object instance.

Parameters:

include_defaults (bool, optional) – Whether to include properties that haven’t been explicitly set since the object was created. (default: True)

Returns:

mapping from property names to their values

Return type:

dict

query_properties_with_values(query: Callable[[PropertyDescriptor[Any]], bool], *, include_defaults: bool = True, include_undefined: bool = False) dict[str, Any]#

Query the properties values of HasProps instances with a predicate.

Parameters:
  • query (callable) – A callable that accepts property descriptors and returns True or False

  • include_defaults (bool, optional) – Whether to include properties that have not been explicitly set by a user (default: True)

Returns:

mapping of property names and values for matching properties

Return type:

dict

references() set[Model]#

Returns all Models that this object has references to.

remove_on_change(attr: str, *callbacks: Callable[[str, Any, Any], None]) None#

Remove a callback from this object

select(selector: SelectorType) Iterable[Model]#

Query this object and all of its references for objects that match the given selector.

Parameters:

selector (JSON-like) –

Returns:

seq[Model]

select_one(selector: SelectorType) Model | None#

Query this object and all of its references for objects that match the given selector. Raises an error if more than one object is found. Returns single matching object, or None if nothing is found :param selector: :type selector: JSON-like

Returns:

Model

set_from_json(name: str, value: Any, *, setter: Setter | None = None) None#

Set a property value on this object from JSON.

Parameters:
  • name – (str) : name of the attribute to set

  • json – (JSON-value) : value to set to the attribute to

  • models (dict or None, optional) –

    Mapping of model ids to models (default: None)

    This is needed in cases where the attributes to update also have values that have references.

  • setter (ClientSession or ServerSession or None, optional) –

    This is used to prevent “boomerang” updates to Bokeh apps.

    In the context of a Bokeh server application, incoming updates to properties will be annotated with the session that is doing the updating. This value is propagated through any subsequent change notifications that the update triggers. The session can compare the event setter to itself, and suppress any updates that originate from itself.

Returns:

None

set_select(selector: type[Model] | SelectorType, updates: dict[str, Any]) None#

Update objects that match a given selector with the specified attribute/value updates.

Parameters:
  • selector (JSON-like) –

  • updates (dict) –

Returns:

None

themed_values() dict[str, Any] | None#

Get any theme-provided overrides.

Results are returned as a dict from property name to value, or None if no theme overrides any values for this instance.

Returns:

dict or None

to_serializable(serializer: Serializer) ObjectRefRep#

Converts this object to a serializable representation.

trigger(attr: str, old: Any, new: Any, hint: DocumentPatchedEvent | None = None, setter: Setter | None = None) None#
unapply_theme() None#

Remove any themed values and restore defaults.

Returns:

None

update(**kwargs: Any) None#

Updates the object’s properties from the given keyword arguments.

Returns:

None

Examples

The following are equivalent:

from bokeh.models import Range1d

r = Range1d

# set properties individually:
r.start = 10
r.end = 20

# update properties together:
r.update(start=10, end=20)
property document: Document | None#

The Document this model is attached to (can be None)

class Expression(*args: Any, id: ID | None = None, **kwargs: Any)[source]#

Bases: Model

Base class for Expression models that represent a computation to be carried out on the client-side.

JavaScript implementations should implement the following methods:

Note

If you wish for results to be cached per source and updated only if the source changes, implement _v_compute: (source) instead.

Note

This is an abstract base class used to help organize the hierarchy of Bokeh model types. It is not useful to instantiate on its own.

JSON Prototype
{
  "id": "p118533",
  "js_event_callbacks": {
    "type": "map"
  },
  "js_property_callbacks": {
    "type": "map"
  },
  "name": null,
  "subscribed_events": {
    "type": "set"
  },
  "syncable": true,
  "tags": []
}

Public Data Attributes:

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

id

subscribed_events

Collection of events that are subscribed to by Python callbacks.

Inherited from Model

id

ref

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

js_event_callbacks

A mapping of event names to lists of CustomJS callbacks.

js_property_callbacks

A mapping of attribute names to lists of CustomJS callbacks, to be set up on BokehJS side when the document is created.

subscribed_events

Collection of events that are subscribed to by Python callbacks.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

Inherited from HasDocumentRef

document

The Document this model is attached to (can be None)

Inherited from PropertyCallbackManager

document

Inherited from EventCallbackManager

document

id

subscribed_events

Public Methods:

__init__(*[, syncable, tags])

Inherited from Model

__init_subclass__()

This method is called when a class is subclassed.

__new__(cls, *args[, id])

__init__(*args, **kwargs)

__str__()

Return str(self).

__repr__()

Return repr(self).

destroy()

Clean up references to the document and property

parameters()

Generate Python Parameter values suitable for functions that are derived from the glyph.

js_on_event(event, *callbacks)

js_link(attr, other, other_attr[, attr_selector])

Link two Bokeh model properties using JavaScript.

js_on_change(event, *callbacks)

Attach a CustomJS callback to an arbitrary BokehJS model event.

on_change(attr, *callbacks)

Add a callback on this object to trigger when attr changes.

references()

Returns all Models that this object has references to.

select(selector)

Query this object and all of its references for objects that match the given selector.

select_one(selector)

Query this object and all of its references for objects that match the given selector.

set_select(selector, updates)

Update objects that match a given selector with the specified attribute/value updates.

to_serializable(serializer)

Converts this object to a serializable representation.

trigger(attr, old, new[, hint, setter])

Inherited from HasProps

__init_subclass__()

This method is called when a class is subclassed.

__init__(**properties)

__setattr__(name, value)

Intercept attribute setting on HasProps in order to special case a few situations:

__getattr__(name)

Intercept attribute setting on HasProps in order to special case a few situations:

__str__()

Return str(self).

__repr__()

Return repr(self).

equals(other)

Structural equality of models.

to_serializable(serializer)

Converts this object to a serializable representation.

set_from_json(name, value, *[, setter])

Set a property value on this object from JSON.

update(**kwargs)

Updates the object's properties from the given keyword arguments.

lookup()

Find the PropertyDescriptor for a Bokeh property on a class, given the property name.

properties()

Collect the names of properties on this class.

descriptors()

List of property descriptors in the order of definition.

properties_with_refs()

Collect the names of all properties on this class that also have references.

dataspecs()

Collect the names of all DataSpec properties on this class.

properties_with_values(*[, ...])

Collect a dict mapping property names to their values.

query_properties_with_values(query, *[, ...])

Query the properties values of HasProps instances with a predicate.

themed_values()

Get any theme-provided overrides.

apply_theme(property_values)

Apply a set of theme values which will be used rather than defaults, but will not override application-set values.

unapply_theme()

Remove any themed values and restore defaults.

Inherited from Serializable

to_serializable(serializer)

Converts this object to a serializable representation.

Inherited from HasDocumentRef

__init__(*args, **kw)

Inherited from PropertyCallbackManager

__init__(*args, **kw)

on_change(attr, *callbacks)

Add a callback on this object to trigger when attr changes.

remove_on_change(attr, *callbacks)

Remove a callback from this object

trigger(attr, old, new[, hint, setter])

Trigger callbacks for attr on this object.

Inherited from EventCallbackManager

__init__(*args, **kw)

on_event(event, *callbacks)

Run callbacks when the specified event occurs on this Model


name = None#
Type:

Nullable(String)

An arbitrary, user-supplied name for this model.

This name can be useful when querying the document to retrieve specific Bokeh models.

>>> plot.circle([1,2,3], [4,5,6], name="temp")
>>> plot.select(name="temp")
[GlyphRenderer(id='399d53f5-73e9-44d9-9527-544b761c7705', ...)]

Note

No uniqueness guarantees or other conditions are enforced on any names that are provided, nor is the name used directly by Bokeh for any reason.

syncable = True#
Type:

Bool

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser. Setting to False may be useful to reduce network traffic when dealing with frequently updated objects whose updated values we don’t need.

Note

Setting this property to False will prevent any on_change() callbacks on this object from triggering. However, any JS-side callbacks will still work.

tags = []#
Type:

List

An optional list of arbitrary, user-supplied values to attach to this model.

This data can be useful when querying the document to retrieve specific Bokeh models:

>>> r = plot.circle([1,2,3], [4,5,6])
>>> r.tags = ["foo", 10]
>>> plot.select(tags=['foo', 10])
[GlyphRenderer(id='1de4c3df-a83d-480a-899b-fb263d3d5dd9', ...)]

Or simply a convenient way to attach any necessary metadata to a model that can be accessed by CustomJS callbacks, etc.

Note

No uniqueness guarantees or other conditions are enforced on any tags that are provided, nor are the tags used directly by Bokeh for any reason.

apply_theme(property_values: dict[str, Any]) None#

Apply a set of theme values which will be used rather than defaults, but will not override application-set values.

The passed-in dictionary may be kept around as-is and shared with other instances to save memory (so neither the caller nor the HasProps instance should modify it).

Parameters:

property_values (dict) – theme values to use in place of defaults

Returns:

None

classmethod dataspecs() dict[str, DataSpec]#

Collect the names of all DataSpec properties on this class.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Returns:

names of DataSpec properties

Return type:

set[str]

classmethod descriptors() list[PropertyDescriptor[Any]]#

List of property descriptors in the order of definition.

destroy() None#

Clean up references to the document and property

equals(other: HasProps) bool#

Structural equality of models.

Parameters:

other (HasProps) – the other instance to compare to

Returns:

True, if properties are structurally equal, otherwise False

Link two Bokeh model properties using JavaScript.

This is a convenience method that simplifies adding a CustomJS callback to update one Bokeh model property whenever another changes value.

Parameters:
  • attr (str) – The name of a Bokeh property on this model

  • other (Model) – A Bokeh model to link to self.attr

  • other_attr (str) – The property on other to link together

  • attr_selector (Union[int, str]) – The index to link an item in a subscriptable attr

Added in version 1.1

Raises:

ValueError

Examples

This code with js_link:

select.js_link('value', plot, 'sizing_mode')

is equivalent to the following:

from bokeh.models import CustomJS
select.js_on_change('value',
    CustomJS(args=dict(other=plot),
             code="other.sizing_mode = this.value"
    )
)

Additionally, to use attr_selector to attach the left side of a range slider to a plot’s x_range:

range_slider.js_link('value', plot.x_range, 'start', attr_selector=0)

which is equivalent to:

from bokeh.models import CustomJS
range_slider.js_on_change('value',
    CustomJS(args=dict(other=plot.x_range),
             code="other.start = this.value[0]"
    )
)
js_on_change(event: str, *callbacks: JSEventCallback) None#

Attach a CustomJS callback to an arbitrary BokehJS model event.

On the BokehJS side, change events for model properties have the form "change:property_name". As a convenience, if the event name passed to this method is also the name of a property on the model, then it will be prefixed with "change:" automatically:

# these two are equivalent
source.js_on_change('data', callback)
source.js_on_change('change:data', callback)

However, there are other kinds of events that can be useful to respond to, in addition to property change events. For example to run a callback whenever data is streamed to a ColumnDataSource, use the "stream" event on the source:

source.js_on_change('streaming', callback)
classmethod lookup(name: str, *, raises: bool = True) PropertyDescriptor[Any] | None#

Find the PropertyDescriptor for a Bokeh property on a class, given the property name.

Parameters:
  • name (str) – name of the property to search for

  • raises (bool) – whether to raise or return None if missing

Returns:

descriptor for property named name

Return type:

PropertyDescriptor

on_change(attr: str, *callbacks: PropertyCallback) None#

Add a callback on this object to trigger when attr changes.

Parameters:
  • attr (str) – an attribute name on this object

  • *callbacks (callable) – callback functions to register

Returns:

None

Example:

widget.on_change('value', callback1, callback2, ..., callback_n)
on_event(event: str | type[Event], *callbacks: EventCallback) None#

Run callbacks when the specified event occurs on this Model

Not all Events are supported for all Models. See specific Events in bokeh.events for more information on which Models are able to trigger them.

classmethod parameters() list[Parameter]#

Generate Python Parameter values suitable for functions that are derived from the glyph.

Returns:

list(Parameter)

classmethod properties(*, _with_props: bool = False) set[str] | dict[str, Property[Any]]#

Collect the names of properties on this class.

Warning

In a future version of Bokeh, this method will return a dictionary mapping property names to property objects. To future-proof this current usage of this method, wrap the return value in list.

Returns:

property names

classmethod properties_with_refs() dict[str, Property[Any]]#

Collect the names of all properties on this class that also have references.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Returns:

names of properties that have references

Return type:

set[str]

properties_with_values(*, include_defaults: bool = True, include_undefined: bool = False) dict[str, Any]#

Collect a dict mapping property names to their values.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Non-serializable properties are skipped and property values are in “serialized” format which may be slightly different from the values you would normally read from the properties; the intent of this method is to return the information needed to losslessly reconstitute the object instance.

Parameters:

include_defaults (bool, optional) – Whether to include properties that haven’t been explicitly set since the object was created. (default: True)

Returns:

mapping from property names to their values

Return type:

dict

query_properties_with_values(query: Callable[[PropertyDescriptor[Any]], bool], *, include_defaults: bool = True, include_undefined: bool = False) dict[str, Any]#

Query the properties values of HasProps instances with a predicate.

Parameters:
  • query (callable) – A callable that accepts property descriptors and returns True or False

  • include_defaults (bool, optional) – Whether to include properties that have not been explicitly set by a user (default: True)

Returns:

mapping of property names and values for matching properties

Return type:

dict

references() set[Model]#

Returns all Models that this object has references to.

remove_on_change(attr: str, *callbacks: Callable[[str, Any, Any], None]) None#

Remove a callback from this object

select(selector: SelectorType) Iterable[Model]#

Query this object and all of its references for objects that match the given selector.

Parameters:

selector (JSON-like) –

Returns:

seq[Model]

select_one(selector: SelectorType) Model | None#

Query this object and all of its references for objects that match the given selector. Raises an error if more than one object is found. Returns single matching object, or None if nothing is found :param selector: :type selector: JSON-like

Returns:

Model

set_from_json(name: str, value: Any, *, setter: Setter | None = None) None#

Set a property value on this object from JSON.

Parameters:
  • name – (str) : name of the attribute to set

  • json – (JSON-value) : value to set to the attribute to

  • models (dict or None, optional) –

    Mapping of model ids to models (default: None)

    This is needed in cases where the attributes to update also have values that have references.

  • setter (ClientSession or ServerSession or None, optional) –

    This is used to prevent “boomerang” updates to Bokeh apps.

    In the context of a Bokeh server application, incoming updates to properties will be annotated with the session that is doing the updating. This value is propagated through any subsequent change notifications that the update triggers. The session can compare the event setter to itself, and suppress any updates that originate from itself.

Returns:

None

set_select(selector: type[Model] | SelectorType, updates: dict[str, Any]) None#

Update objects that match a given selector with the specified attribute/value updates.

Parameters:
  • selector (JSON-like) –

  • updates (dict) –

Returns:

None

themed_values() dict[str, Any] | None#

Get any theme-provided overrides.

Results are returned as a dict from property name to value, or None if no theme overrides any values for this instance.

Returns:

dict or None

to_serializable(serializer: Serializer) ObjectRefRep#

Converts this object to a serializable representation.

trigger(attr: str, old: Any, new: Any, hint: DocumentPatchedEvent | None = None, setter: Setter | None = None) None#
unapply_theme() None#

Remove any themed values and restore defaults.

Returns:

None

update(**kwargs: Any) None#

Updates the object’s properties from the given keyword arguments.

Returns:

None

Examples

The following are equivalent:

from bokeh.models import Range1d

r = Range1d

# set properties individually:
r.start = 10
r.end = 20

# update properties together:
r.update(start=10, end=20)
property document: Document | None#

The Document this model is attached to (can be None)

class PolarTransform(*args: Any, id: ID | None = None, **kwargs: Any)[source]#

Bases: CoordinateTransform

Transform from polar to cartesian coordinates.

JSON Prototype
{
  "angle": {
    "field": "angle",
    "type": "field"
  },
  "direction": "anticlock",
  "id": "p118537",
  "js_event_callbacks": {
    "type": "map"
  },
  "js_property_callbacks": {
    "type": "map"
  },
  "name": null,
  "radius": {
    "field": "radius",
    "type": "field"
  },
  "subscribed_events": {
    "type": "set"
  },
  "syncable": true,
  "tags": []
}

Public Data Attributes:

radius

The radial coordinate (i.e.

angle_units

Units to use for the associated property: deg, rad, grad or turn

angle

The angular coordinate (i.e.

direction

Whether angle measures clockwise or anti-clockwise from the reference axis.

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

id

subscribed_events

Collection of events that are subscribed to by Python callbacks.

Inherited from CoordinateTransform

x

y

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

id

subscribed_events

Collection of events that are subscribed to by Python callbacks.

Inherited from Expression

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

id

subscribed_events

Collection of events that are subscribed to by Python callbacks.

Inherited from Model

id

ref

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

js_event_callbacks

A mapping of event names to lists of CustomJS callbacks.

js_property_callbacks

A mapping of attribute names to lists of CustomJS callbacks, to be set up on BokehJS side when the document is created.

subscribed_events

Collection of events that are subscribed to by Python callbacks.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

Inherited from HasDocumentRef

document

The Document this model is attached to (can be None)

Inherited from PropertyCallbackManager

document

Inherited from EventCallbackManager

document

id

subscribed_events

Public Methods:

__init__(*[, angle_units, direction, name, ...])

Inherited from CoordinateTransform

__init__(*[, syncable, tags])

Inherited from Expression

__init__(*[, syncable, tags])

Inherited from Model

__init_subclass__()

This method is called when a class is subclassed.

__new__(cls, *args[, id])

__init__(*args, **kwargs)

__str__()

Return str(self).

__repr__()

Return repr(self).

destroy()

Clean up references to the document and property

parameters()

Generate Python Parameter values suitable for functions that are derived from the glyph.

js_on_event(event, *callbacks)

js_link(attr, other, other_attr[, attr_selector])

Link two Bokeh model properties using JavaScript.

js_on_change(event, *callbacks)

Attach a CustomJS callback to an arbitrary BokehJS model event.

on_change(attr, *callbacks)

Add a callback on this object to trigger when attr changes.

references()

Returns all Models that this object has references to.

select(selector)

Query this object and all of its references for objects that match the given selector.

select_one(selector)

Query this object and all of its references for objects that match the given selector.

set_select(selector, updates)

Update objects that match a given selector with the specified attribute/value updates.

to_serializable(serializer)

Converts this object to a serializable representation.

trigger(attr, old, new[, hint, setter])

Inherited from HasProps

__init_subclass__()

This method is called when a class is subclassed.

__init__(**properties)

__setattr__(name, value)

Intercept attribute setting on HasProps in order to special case a few situations:

__getattr__(name)

Intercept attribute setting on HasProps in order to special case a few situations:

__str__()

Return str(self).

__repr__()

Return repr(self).

equals(other)

Structural equality of models.

to_serializable(serializer)

Converts this object to a serializable representation.

set_from_json(name, value, *[, setter])

Set a property value on this object from JSON.

update(**kwargs)

Updates the object's properties from the given keyword arguments.

lookup()

Find the PropertyDescriptor for a Bokeh property on a class, given the property name.

properties()

Collect the names of properties on this class.

descriptors()

List of property descriptors in the order of definition.

properties_with_refs()

Collect the names of all properties on this class that also have references.

dataspecs()

Collect the names of all DataSpec properties on this class.

properties_with_values(*[, ...])

Collect a dict mapping property names to their values.

query_properties_with_values(query, *[, ...])

Query the properties values of HasProps instances with a predicate.

themed_values()

Get any theme-provided overrides.

apply_theme(property_values)

Apply a set of theme values which will be used rather than defaults, but will not override application-set values.

unapply_theme()

Remove any themed values and restore defaults.

Inherited from Serializable

to_serializable(serializer)

Converts this object to a serializable representation.

Inherited from HasDocumentRef

__init__(*args, **kw)

Inherited from PropertyCallbackManager

__init__(*args, **kw)

on_change(attr, *callbacks)

Add a callback on this object to trigger when attr changes.

remove_on_change(attr, *callbacks)

Remove a callback from this object

trigger(attr, old, new[, hint, setter])

Trigger callbacks for attr on this object.

Inherited from EventCallbackManager

__init__(*args, **kw)

on_event(event, *callbacks)

Run callbacks when the specified event occurs on this Model


angle = Field(field='angle', transform=Unspecified, units=Unspecified)#
Type:

AngleSpec

The angular coordinate (i.e. the angle from the reference axis).

angle_units = 'rad'#
Type:

NotSerialized(Enum(AngleUnits))

Units to use for the associated property: deg, rad, grad or turn

direction = 'anticlock'#
Type:

Enum(Direction)

Whether angle measures clockwise or anti-clockwise from the reference axis.

name = None#
Type:

Nullable(String)

An arbitrary, user-supplied name for this model.

This name can be useful when querying the document to retrieve specific Bokeh models.

>>> plot.circle([1,2,3], [4,5,6], name="temp")
>>> plot.select(name="temp")
[GlyphRenderer(id='399d53f5-73e9-44d9-9527-544b761c7705', ...)]

Note

No uniqueness guarantees or other conditions are enforced on any names that are provided, nor is the name used directly by Bokeh for any reason.

radius = Field(field='radius', transform=Unspecified, units=Unspecified)#
Type:

NumberSpec

The radial coordinate (i.e. the distance from the origin).

Negative radius is allowed, which is equivalent to using positive radius and changing direction to the opposite value.

syncable = True#
Type:

Bool

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser. Setting to False may be useful to reduce network traffic when dealing with frequently updated objects whose updated values we don’t need.

Note

Setting this property to False will prevent any on_change() callbacks on this object from triggering. However, any JS-side callbacks will still work.

tags = []#
Type:

List

An optional list of arbitrary, user-supplied values to attach to this model.

This data can be useful when querying the document to retrieve specific Bokeh models:

>>> r = plot.circle([1,2,3], [4,5,6])
>>> r.tags = ["foo", 10]
>>> plot.select(tags=['foo', 10])
[GlyphRenderer(id='1de4c3df-a83d-480a-899b-fb263d3d5dd9', ...)]

Or simply a convenient way to attach any necessary metadata to a model that can be accessed by CustomJS callbacks, etc.

Note

No uniqueness guarantees or other conditions are enforced on any tags that are provided, nor are the tags used directly by Bokeh for any reason.

apply_theme(property_values: dict[str, Any]) None#

Apply a set of theme values which will be used rather than defaults, but will not override application-set values.

The passed-in dictionary may be kept around as-is and shared with other instances to save memory (so neither the caller nor the HasProps instance should modify it).

Parameters:

property_values (dict) – theme values to use in place of defaults

Returns:

None

classmethod dataspecs() dict[str, DataSpec]#

Collect the names of all DataSpec properties on this class.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Returns:

names of DataSpec properties

Return type:

set[str]

classmethod descriptors() list[PropertyDescriptor[Any]]#

List of property descriptors in the order of definition.

destroy() None#

Clean up references to the document and property

equals(other: HasProps) bool#

Structural equality of models.

Parameters:

other (HasProps) – the other instance to compare to

Returns:

True, if properties are structurally equal, otherwise False

Link two Bokeh model properties using JavaScript.

This is a convenience method that simplifies adding a CustomJS callback to update one Bokeh model property whenever another changes value.

Parameters:
  • attr (str) – The name of a Bokeh property on this model

  • other (Model) – A Bokeh model to link to self.attr

  • other_attr (str) – The property on other to link together

  • attr_selector (Union[int, str]) – The index to link an item in a subscriptable attr

Added in version 1.1

Raises:

ValueError

Examples

This code with js_link:

select.js_link('value', plot, 'sizing_mode')

is equivalent to the following:

from bokeh.models import CustomJS
select.js_on_change('value',
    CustomJS(args=dict(other=plot),
             code="other.sizing_mode = this.value"
    )
)

Additionally, to use attr_selector to attach the left side of a range slider to a plot’s x_range:

range_slider.js_link('value', plot.x_range, 'start', attr_selector=0)

which is equivalent to:

from bokeh.models import CustomJS
range_slider.js_on_change('value',
    CustomJS(args=dict(other=plot.x_range),
             code="other.start = this.value[0]"
    )
)
js_on_change(event: str, *callbacks: JSEventCallback) None#

Attach a CustomJS callback to an arbitrary BokehJS model event.

On the BokehJS side, change events for model properties have the form "change:property_name". As a convenience, if the event name passed to this method is also the name of a property on the model, then it will be prefixed with "change:" automatically:

# these two are equivalent
source.js_on_change('data', callback)
source.js_on_change('change:data', callback)

However, there are other kinds of events that can be useful to respond to, in addition to property change events. For example to run a callback whenever data is streamed to a ColumnDataSource, use the "stream" event on the source:

source.js_on_change('streaming', callback)
classmethod lookup(name: str, *, raises: bool = True) PropertyDescriptor[Any] | None#

Find the PropertyDescriptor for a Bokeh property on a class, given the property name.

Parameters:
  • name (str) – name of the property to search for

  • raises (bool) – whether to raise or return None if missing

Returns:

descriptor for property named name

Return type:

PropertyDescriptor

on_change(attr: str, *callbacks: PropertyCallback) None#

Add a callback on this object to trigger when attr changes.

Parameters:
  • attr (str) – an attribute name on this object

  • *callbacks (callable) – callback functions to register

Returns:

None

Example:

widget.on_change('value', callback1, callback2, ..., callback_n)
on_event(event: str | type[Event], *callbacks: EventCallback) None#

Run callbacks when the specified event occurs on this Model

Not all Events are supported for all Models. See specific Events in bokeh.events for more information on which Models are able to trigger them.

classmethod parameters() list[Parameter]#

Generate Python Parameter values suitable for functions that are derived from the glyph.

Returns:

list(Parameter)

classmethod properties(*, _with_props: bool = False) set[str] | dict[str, Property[Any]]#

Collect the names of properties on this class.

Warning

In a future version of Bokeh, this method will return a dictionary mapping property names to property objects. To future-proof this current usage of this method, wrap the return value in list.

Returns:

property names

classmethod properties_with_refs() dict[str, Property[Any]]#

Collect the names of all properties on this class that also have references.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Returns:

names of properties that have references

Return type:

set[str]

properties_with_values(*, include_defaults: bool = True, include_undefined: bool = False) dict[str, Any]#

Collect a dict mapping property names to their values.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Non-serializable properties are skipped and property values are in “serialized” format which may be slightly different from the values you would normally read from the properties; the intent of this method is to return the information needed to losslessly reconstitute the object instance.

Parameters:

include_defaults (bool, optional) – Whether to include properties that haven’t been explicitly set since the object was created. (default: True)

Returns:

mapping from property names to their values

Return type:

dict

query_properties_with_values(query: Callable[[PropertyDescriptor[Any]], bool], *, include_defaults: bool = True, include_undefined: bool = False) dict[str, Any]#

Query the properties values of HasProps instances with a predicate.

Parameters:
  • query (callable) – A callable that accepts property descriptors and returns True or False

  • include_defaults (bool, optional) – Whether to include properties that have not been explicitly set by a user (default: True)

Returns:

mapping of property names and values for matching properties

Return type:

dict

references() set[Model]#

Returns all Models that this object has references to.

remove_on_change(attr: str, *callbacks: Callable[[str, Any, Any], None]) None#

Remove a callback from this object

select(selector: SelectorType) Iterable[Model]#

Query this object and all of its references for objects that match the given selector.

Parameters:

selector (JSON-like) –

Returns:

seq[Model]

select_one(selector: SelectorType) Model | None#

Query this object and all of its references for objects that match the given selector. Raises an error if more than one object is found. Returns single matching object, or None if nothing is found :param selector: :type selector: JSON-like

Returns:

Model

set_from_json(name: str, value: Any, *, setter: Setter | None = None) None#

Set a property value on this object from JSON.

Parameters:
  • name – (str) : name of the attribute to set

  • json – (JSON-value) : value to set to the attribute to

  • models (dict or None, optional) –

    Mapping of model ids to models (default: None)

    This is needed in cases where the attributes to update also have values that have references.

  • setter (ClientSession or ServerSession or None, optional) –

    This is used to prevent “boomerang” updates to Bokeh apps.

    In the context of a Bokeh server application, incoming updates to properties will be annotated with the session that is doing the updating. This value is propagated through any subsequent change notifications that the update triggers. The session can compare the event setter to itself, and suppress any updates that originate from itself.

Returns:

None

set_select(selector: type[Model] | SelectorType, updates: dict[str, Any]) None#

Update objects that match a given selector with the specified attribute/value updates.

Parameters:
  • selector (JSON-like) –

  • updates (dict) –

Returns:

None

themed_values() dict[str, Any] | None#

Get any theme-provided overrides.

Results are returned as a dict from property name to value, or None if no theme overrides any values for this instance.

Returns:

dict or None

to_serializable(serializer: Serializer) ObjectRefRep#

Converts this object to a serializable representation.

trigger(attr: str, old: Any, new: Any, hint: DocumentPatchedEvent | None = None, setter: Setter | None = None) None#
unapply_theme() None#

Remove any themed values and restore defaults.

Returns:

None

update(**kwargs: Any) None#

Updates the object’s properties from the given keyword arguments.

Returns:

None

Examples

The following are equivalent:

from bokeh.models import Range1d

r = Range1d

# set properties individually:
r.start = 10
r.end = 20

# update properties together:
r.update(start=10, end=20)
property document: Document | None#

The Document this model is attached to (can be None)

class Stack(*args: Any, id: ID | None = None, **kwargs: Any)[source]#

Bases: Expression

An expression for generating arrays by summing different columns from a ColumnDataSource.

This expression is useful for implementing stacked bar charts at a low level.

JSON Prototype
{
  "fields": [],
  "id": "p118545",
  "js_event_callbacks": {
    "type": "map"
  },
  "js_property_callbacks": {
    "type": "map"
  },
  "name": null,
  "subscribed_events": {
    "type": "set"
  },
  "syncable": true,
  "tags": []
}

Public Data Attributes:

fields

A sequence of fields from a ColumnDataSource to sum (elementwise).

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

id

subscribed_events

Collection of events that are subscribed to by Python callbacks.

Inherited from Expression

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

id

subscribed_events

Collection of events that are subscribed to by Python callbacks.

Inherited from Model

id

ref

name

An arbitrary, user-supplied name for this model.

tags

An optional list of arbitrary, user-supplied values to attach to this model.

js_event_callbacks

A mapping of event names to lists of CustomJS callbacks.

js_property_callbacks

A mapping of attribute names to lists of CustomJS callbacks, to be set up on BokehJS side when the document is created.

subscribed_events

Collection of events that are subscribed to by Python callbacks.

syncable

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser.

document

The Document this model is attached to (can be None)

Inherited from HasDocumentRef

document

The Document this model is attached to (can be None)

Inherited from PropertyCallbackManager

document

Inherited from EventCallbackManager

document

id

subscribed_events

Public Methods:

__init__(*[, name, syncable, tags])

Inherited from Expression

__init__(*[, syncable, tags])

Inherited from Model

__init_subclass__()

This method is called when a class is subclassed.

__new__(cls, *args[, id])

__init__(*args, **kwargs)

__str__()

Return str(self).

__repr__()

Return repr(self).

destroy()

Clean up references to the document and property

parameters()

Generate Python Parameter values suitable for functions that are derived from the glyph.

js_on_event(event, *callbacks)

js_link(attr, other, other_attr[, attr_selector])

Link two Bokeh model properties using JavaScript.

js_on_change(event, *callbacks)

Attach a CustomJS callback to an arbitrary BokehJS model event.

on_change(attr, *callbacks)

Add a callback on this object to trigger when attr changes.

references()

Returns all Models that this object has references to.

select(selector)

Query this object and all of its references for objects that match the given selector.

select_one(selector)

Query this object and all of its references for objects that match the given selector.

set_select(selector, updates)

Update objects that match a given selector with the specified attribute/value updates.

to_serializable(serializer)

Converts this object to a serializable representation.

trigger(attr, old, new[, hint, setter])

Inherited from HasProps

__init_subclass__()

This method is called when a class is subclassed.

__init__(**properties)

__setattr__(name, value)

Intercept attribute setting on HasProps in order to special case a few situations:

__getattr__(name)

Intercept attribute setting on HasProps in order to special case a few situations:

__str__()

Return str(self).

__repr__()

Return repr(self).

equals(other)

Structural equality of models.

to_serializable(serializer)

Converts this object to a serializable representation.

set_from_json(name, value, *[, setter])

Set a property value on this object from JSON.

update(**kwargs)

Updates the object's properties from the given keyword arguments.

lookup()

Find the PropertyDescriptor for a Bokeh property on a class, given the property name.

properties()

Collect the names of properties on this class.

descriptors()

List of property descriptors in the order of definition.

properties_with_refs()

Collect the names of all properties on this class that also have references.

dataspecs()

Collect the names of all DataSpec properties on this class.

properties_with_values(*[, ...])

Collect a dict mapping property names to their values.

query_properties_with_values(query, *[, ...])

Query the properties values of HasProps instances with a predicate.

themed_values()

Get any theme-provided overrides.

apply_theme(property_values)

Apply a set of theme values which will be used rather than defaults, but will not override application-set values.

unapply_theme()

Remove any themed values and restore defaults.

Inherited from Serializable

to_serializable(serializer)

Converts this object to a serializable representation.

Inherited from HasDocumentRef

__init__(*args, **kw)

Inherited from PropertyCallbackManager

__init__(*args, **kw)

on_change(attr, *callbacks)

Add a callback on this object to trigger when attr changes.

remove_on_change(attr, *callbacks)

Remove a callback from this object

trigger(attr, old, new[, hint, setter])

Trigger callbacks for attr on this object.

Inherited from EventCallbackManager

__init__(*args, **kw)

on_event(event, *callbacks)

Run callbacks when the specified event occurs on this Model


fields = []#
Type:

Seq(String)

A sequence of fields from a ColumnDataSource to sum (elementwise). For example:

Stack(fields=['sales', 'marketing'])

Will compute an array of values (in the browser) by adding the elements of the 'sales' and 'marketing' columns of a data source.

name = None#
Type:

Nullable(String)

An arbitrary, user-supplied name for this model.

This name can be useful when querying the document to retrieve specific Bokeh models.

>>> plot.circle([1,2,3], [4,5,6], name="temp")
>>> plot.select(name="temp")
[GlyphRenderer(id='399d53f5-73e9-44d9-9527-544b761c7705', ...)]

Note

No uniqueness guarantees or other conditions are enforced on any names that are provided, nor is the name used directly by Bokeh for any reason.

syncable = True#
Type:

Bool

Indicates whether this model should be synchronized back to a Bokeh server when updated in a web browser. Setting to False may be useful to reduce network traffic when dealing with frequently updated objects whose updated values we don’t need.

Note

Setting this property to False will prevent any on_change() callbacks on this object from triggering. However, any JS-side callbacks will still work.

tags = []#
Type:

List

An optional list of arbitrary, user-supplied values to attach to this model.

This data can be useful when querying the document to retrieve specific Bokeh models:

>>> r = plot.circle([1,2,3], [4,5,6])
>>> r.tags = ["foo", 10]
>>> plot.select(tags=['foo', 10])
[GlyphRenderer(id='1de4c3df-a83d-480a-899b-fb263d3d5dd9', ...)]

Or simply a convenient way to attach any necessary metadata to a model that can be accessed by CustomJS callbacks, etc.

Note

No uniqueness guarantees or other conditions are enforced on any tags that are provided, nor are the tags used directly by Bokeh for any reason.

apply_theme(property_values: dict[str, Any]) None#

Apply a set of theme values which will be used rather than defaults, but will not override application-set values.

The passed-in dictionary may be kept around as-is and shared with other instances to save memory (so neither the caller nor the HasProps instance should modify it).

Parameters:

property_values (dict) – theme values to use in place of defaults

Returns:

None

classmethod dataspecs() dict[str, DataSpec]#

Collect the names of all DataSpec properties on this class.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Returns:

names of DataSpec properties

Return type:

set[str]

classmethod descriptors() list[PropertyDescriptor[Any]]#

List of property descriptors in the order of definition.

destroy() None#

Clean up references to the document and property

equals(other: HasProps) bool#

Structural equality of models.

Parameters:

other (HasProps) – the other instance to compare to

Returns:

True, if properties are structurally equal, otherwise False

Link two Bokeh model properties using JavaScript.

This is a convenience method that simplifies adding a CustomJS callback to update one Bokeh model property whenever another changes value.

Parameters:
  • attr (str) – The name of a Bokeh property on this model

  • other (Model) – A Bokeh model to link to self.attr

  • other_attr (str) – The property on other to link together

  • attr_selector (Union[int, str]) – The index to link an item in a subscriptable attr

Added in version 1.1

Raises:

ValueError

Examples

This code with js_link:

select.js_link('value', plot, 'sizing_mode')

is equivalent to the following:

from bokeh.models import CustomJS
select.js_on_change('value',
    CustomJS(args=dict(other=plot),
             code="other.sizing_mode = this.value"
    )
)

Additionally, to use attr_selector to attach the left side of a range slider to a plot’s x_range:

range_slider.js_link('value', plot.x_range, 'start', attr_selector=0)

which is equivalent to:

from bokeh.models import CustomJS
range_slider.js_on_change('value',
    CustomJS(args=dict(other=plot.x_range),
             code="other.start = this.value[0]"
    )
)
js_on_change(event: str, *callbacks: JSEventCallback) None#

Attach a CustomJS callback to an arbitrary BokehJS model event.

On the BokehJS side, change events for model properties have the form "change:property_name". As a convenience, if the event name passed to this method is also the name of a property on the model, then it will be prefixed with "change:" automatically:

# these two are equivalent
source.js_on_change('data', callback)
source.js_on_change('change:data', callback)

However, there are other kinds of events that can be useful to respond to, in addition to property change events. For example to run a callback whenever data is streamed to a ColumnDataSource, use the "stream" event on the source:

source.js_on_change('streaming', callback)
classmethod lookup(name: str, *, raises: bool = True) PropertyDescriptor[Any] | None#

Find the PropertyDescriptor for a Bokeh property on a class, given the property name.

Parameters:
  • name (str) – name of the property to search for

  • raises (bool) – whether to raise or return None if missing

Returns:

descriptor for property named name

Return type:

PropertyDescriptor

on_change(attr: str, *callbacks: PropertyCallback) None#

Add a callback on this object to trigger when attr changes.

Parameters:
  • attr (str) – an attribute name on this object

  • *callbacks (callable) – callback functions to register

Returns:

None

Example:

widget.on_change('value', callback1, callback2, ..., callback_n)
on_event(event: str | type[Event], *callbacks: EventCallback) None#

Run callbacks when the specified event occurs on this Model

Not all Events are supported for all Models. See specific Events in bokeh.events for more information on which Models are able to trigger them.

classmethod parameters() list[Parameter]#

Generate Python Parameter values suitable for functions that are derived from the glyph.

Returns:

list(Parameter)

classmethod properties(*, _with_props: bool = False) set[str] | dict[str, Property[Any]]#

Collect the names of properties on this class.

Warning

In a future version of Bokeh, this method will return a dictionary mapping property names to property objects. To future-proof this current usage of this method, wrap the return value in list.

Returns:

property names

classmethod properties_with_refs() dict[str, Property[Any]]#

Collect the names of all properties on this class that also have references.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Returns:

names of properties that have references

Return type:

set[str]

properties_with_values(*, include_defaults: bool = True, include_undefined: bool = False) dict[str, Any]#

Collect a dict mapping property names to their values.

This method always traverses the class hierarchy and includes properties defined on any parent classes.

Non-serializable properties are skipped and property values are in “serialized” format which may be slightly different from the values you would normally read from the properties; the intent of this method is to return the information needed to losslessly reconstitute the object instance.

Parameters:

include_defaults (bool, optional) – Whether to include properties that haven’t been explicitly set since the object was created. (default: True)

Returns:

mapping from property names to their values

Return type:

dict

query_properties_with_values(query: Callable[[PropertyDescriptor[Any]], bool], *, include_defaults: bool = True, include_undefined: bool = False) dict[str, Any]#

Query the properties values of HasProps instances with a predicate.

Parameters:
  • query (callable) – A callable that accepts property descriptors and returns True or False

  • include_defaults (bool, optional) – Whether to include properties that have not been explicitly set by a user (default: True)

Returns:

mapping of property names and values for matching properties

Return type:

dict

references() set[Model]#

Returns all Models that this object has references to.

remove_on_change(attr: str, *callbacks: Callable[[str, Any, Any], None]) None#

Remove a callback from this object

select(selector: SelectorType) Iterable[Model]#

Query this object and all of its references for objects that match the given selector.

Parameters:

selector (JSON-like) –

Returns:

seq[Model]

select_one(selector: SelectorType) Model | None#

Query this object and all of its references for objects that match the given selector. Raises an error if more than one object is found. Returns single matching object, or None if nothing is found :param selector: :type selector: JSON-like

Returns:

Model

set_from_json(name: str, value: Any, *, setter: Setter | None = None) None#

Set a property value on this object from JSON.

Parameters:
  • name – (str) : name of the attribute to set

  • json – (JSON-value) : value to set to the attribute to

  • models (dict or None, optional) –

    Mapping of model ids to models (default: None)

    This is needed in cases where the attributes to update also have values that have references.

  • setter (ClientSession or ServerSession or None, optional) –

    This is used to prevent “boomerang” updates to Bokeh apps.

    In the context of a Bokeh server application, incoming updates to properties will be annotated with the session that is doing the updating. This value is propagated through any subsequent change notifications that the update triggers. The session can compare the event setter to itself, and suppress any updates that originate from itself.

Returns:

None

set_select(selector: type[Model] | SelectorType, updates: dict[str, Any]) None#

Update objects that match a given selector with the specified attribute/value updates.

Parameters:
  • selector (JSON-like) –

  • updates (dict) –

Returns:

None

themed_values() dict[str, Any] | None#

Get any theme-provided overrides.

Results are returned as a dict from property name to value, or None if no theme overrides any values for this instance.

Returns:

dict or None

to_serializable(serializer: Serializer) ObjectRefRep#

Converts this object to a serializable representation.

trigger(attr: str, old: Any, new: Any, hint: DocumentPatchedEvent | None = None, setter: Setter | None = None) None#
unapply_theme() None#

Remove any themed values and restore defaults.

Returns:

None

update(**kwargs: Any) None#

Updates the object’s properties from the given keyword arguments.

Returns:

None

Examples

The following are equivalent:

from bokeh.models import Range1d

r = Range1d

# set properties individually:
r.start = 10
r.end = 20

# update properties together:
r.update(start=10, end=20)
property document: Document | None#

The Document this model is attached to (can be None)