bokeh.models.WheelZoomTool#

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

Bases: Scroll

toolbar icon:

The wheel zoom tool will zoom the plot in and out, centered on the current mouse location.

The wheel zoom tool also activates the border regions of a Plot for “single axis” zooming. For instance, zooming in the vertical border or axis will effect a zoom in the vertical direction only, with the horizontal dimension kept fixed.

Property index#
`description`	`dimensions`
`group`	`hit_test`
`hit_test_behavior`	`hit_test_mode`
`icon`	`level`
`maintain_focus`	`modifiers`
`name`	`renderers`
`speed`	`syncable`
`tags`	`visible`
`zoom_on_axis`	`zoom_together`
`document`

Properties#

description = None#

Type:: Nullable(String)

A string describing the purpose of this tool. If not defined, an auto-generated description will be used. This description will be typically presented in the user interface as a tooltip.

dimensions = 'both'#

Type:: Enum(Dimensions)

Which dimensions the wheel zoom tool is constrained to act in. By default the wheel zoom tool will zoom in any dimension, but can be configured to only zoom horizontally across the width of the plot, or vertically across the height of the plot.

group = True#

Type:: Either(String, Bool)

The name of the group this tool belongs to.

By default set to True, indicating the default group. If set to False, it will prevent the tool from being grouped altogether (regardless of Toolbar.group setting).

hit_test = False#

Type:: Bool

Whether to zoom only those renderer that are being pointed at.

This setting only applies when zooming renderers that were configured with sub-coordinates, otherwise it has no effect.

If True, then hit_test_mode property defines how hit testing is performed and hit_test_behavior allows to configure other aspects of this setup. See respective properties for details.

Note

This property is experimental and may change at any point

hit_test_behavior = 'only_hit'#

Type:: Either(

Instance(GroupBy),

Enum(Enumeration(only_hit))

)

Allows to configure which renderers will be zoomed when hit_test is enabled.

By default (hit_only) only actually hit renderers will be zoomed. An instance of GroupBy model can be used to tell what other renderers should be zoomed when a given one is hit.

Note

This property is experimental and may change at any point

hit_test_mode = 'point'#

Type:: Enum(Enumeration(point, hline, vline))

Allows to configure what geometry to use when hit_test is enabled.

Supported modes are "point" for single point hit testing, and hline and vline for either horizontal or vertical span hit testing.

Note

This property is experimental and may change at any point

icon = None#

Type:: Nullable(

Either(

Image,

Enum(ToolIcon),

Regex,

Regex,

Regex

)

)

An icon to display in the toolbar.

The icon can provided as well known tool icon name, a CSS class selector, a data URI with an image/* MIME, a path to an image, a PIL Image object, or an RGB(A) NumPy array. If None, then the intrinsic icon will be used (may depend on tool’s configuration).

level = 0#

Type:: NonNegative

When working with composite scales (sub-coordinates), this property allows to configure which set of ranges to scale. The default is to scale top-level (frame) ranges.

maintain_focus = True#

Type:: Bool

If True, then hitting a range bound in any one dimension will prevent all further zooming all dimensions. If False, zooming can continue independently in any dimension that has not yet reached its bounds, even if that causes overall focus or aspect ratio to change.

modifiers = {}#

Type:: Struct

Allows to configure a combination of modifier keys, which need to be pressed during the selected gesture for this tool to trigger.

For example, to zoom only when Ctrl and Shift keys are pressed, use:

tool = WheelZoomTool(modifiers=dict(ctrl=True, shift=True))
plot.add_tools(tool)

or alternatively using a concise syntax:

tool = WheelZoomTool(modifiers="ctrl+shift")
plot.add_tools(tool)

Note

Setting modifiers allows this tool to be automatically activated, if Toolbar.active_scroll is set to "auto".

Warning

Configuring modifiers is a platform dependent feature and can make this tool unusable for example on mobile devices.

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.scatter([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.

renderers = 'auto'#

Type:: Either(Auto, List)

Restrict zoom to ranges used by the provided data renderers. If "auto" then all ranges provided by the cartesian frame will be used.

speed = 0.0016666666666666668#

Type:: Float

Speed at which the wheel zooms. Default is 1/600. Optimal range is between 0.001 and 0.09. High values will be clipped. Speed may very between browsers.

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.scatter([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.

visible = True#

Type:: Bool

Whether a tool button associated with this tool should appear in the toolbar.

zoom_on_axis = True#

Type:: Bool

Whether scrolling on an axis (outside the central plot area) should zoom that dimension. If enabled, the behavior of this feature can be configured with zoom_together property.

zoom_together = 'all'#

Type:: Enum(Enumeration(none, cross, all))

Defines the behavior of the tool when zooming on an axis:

"none"
zoom only the axis that’s being interacted with. Any cross axes nor any other axes in the dimension of this axis will be affected.
"cross"
zoom the axis that’s being interacted with and its cross axis, if configured. No other axes in this or cross dimension will be affected.
"all"
zoom all axes in the dimension of the axis that’s being interacted with. All cross axes will be unaffected.

property document: Document | None#: The Document this model is attached to (can be None)

Methods#

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 clear_extensions() → None#

Clear any currently defined custom extensions.

Serialization calls will result in any currently defined custom extensions being included with the generated Document, whether or not there are utilized. This method can be used to clear out all existing custom extension definitions.

clone(**overrides: Any) → Self#

Duplicate a HasProps object.

This creates a shallow clone of the original model, i.e. any mutable containers or child models will not be duplicated. Allows to override particular properties while cloning.

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

classmethod from_string(name: str) → Tool#: Takes a string and returns a corresponding Tool instance.

js_link(attr: str, other: Model, other_attr: str, attr_selector: int | str | None = None) → None#

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 (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: JSChangeCallback) → 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

Examples

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: PropertyCallback) → 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.

Parameters:: 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
value (JSON-value) – value to set to the attribute to
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)