bokeh.models.glyphs.Bezier¶

class Bezier(**kwargs)[source]¶

Render Bézier curves.

For more information consult the Wikipedia article for Bézier curve.

Example

import numpy as np

from bokeh.models import ColumnDataSource, Plot, LinearAxis, Grid
from bokeh.models.glyphs import Bezier
from bokeh.io import curdoc, show

N = 9
x = np.linspace(-2, 2, N)
y = x**2

source = ColumnDataSource(dict(
        x=x,
        y=y,
        xp02=x+0.4,
        xp01=x+0.1,
        xm01=x-0.1,
        yp01=y+0.2,
        ym01=y-0.2,
    )
)

plot = Plot(
    title=None, plot_width=300, plot_height=300,
    h_symmetry=False, v_symmetry=False, min_border=0, toolbar_location=None)

glyph = Bezier(x0="x", y0="y", x1="xp02", y1="y", cx0="xp01", cy0="yp01", cx1="xm01", cy1="ym01", line_color="#d95f02", line_width=2)
plot.add_glyph(source, glyph)

xaxis = LinearAxis()
plot.add_layout(xaxis, 'below')

yaxis = LinearAxis()
plot.add_layout(yaxis, 'left')

plot.add_layout(Grid(dimension=0, ticker=xaxis.ticker))
plot.add_layout(Grid(dimension=1, ticker=yaxis.ticker))

curdoc().add_root(plot)

show(plot)

cx0¶

property type: NumberSpec

The x-coordinates of first control points.

cx1¶

property type: NumberSpec

The x-coordinates of second control points.

cy0¶

property type: NumberSpec

The y-coordinates of first control points.

cy1¶

property type: NumberSpec

The y-coordinates of second control points.

js_event_callbacks¶

property type: Dict ( String , List ( Instance ( CustomJS ) ) )

A mapping of event names to lists of CustomJS callbacks.

Typically, rather then modifying this property directly, callbacks should be added using the Model.js_on_event method:

callback = CustomJS(code="console.log('tap event occurred')")
plot.js_on_event('tap', callback)

js_property_callbacks¶

property type: Dict ( String , List ( Instance ( CustomJS ) ) )

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

Typically, rather then modifying this property directly, callbacks should be added using the Model.js_on_change method:

callback = CustomJS(code="console.log('stuff')")
plot.x_range.js_on_change('start', callback)

line_alpha¶

property type: NumberSpec

The line alpha values for the Bézier curves.

line_cap¶

property type: Enum ( LineCap )

The line cap values for the Bézier curves.

line_color¶

property type: ColorSpec

The line color values for the Bézier curves.

line_dash¶

property type: DashPattern

The line dash values for the Bézier curves.

line_dash_offset¶

property type: Int

The line dash offset values for the Bézier curves.

line_join¶

property type: Enum ( LineJoin )

The line join values for the Bézier curves.

line_width¶

property type: NumberSpec

The line width values for the Bézier curves.

name¶

property type: 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.

subscribed_events¶

property type: List ( String )

List of events that are subscribed to by Python callbacks. This is the set of events that will be communicated from BokehJS back to Python for this model.

tags¶

property type: List ( Any )

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.

x0¶

property type: NumberSpec

The x-coordinates of the starting points.

x1¶

property type: NumberSpec

The x-coordinates of the ending points.

y0¶

property type: NumberSpec

The y-coordinates of the starting points.

y1¶

property type: NumberSpec

The y-coordinates of the ending points.

apply_theme(property_values)¶

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()¶

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 dataspecs_with_props()¶

Collect a dict mapping the names of all DataSpec properties on this class to the associated properties.

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

Returns:	mapping of names and DataSpec properties
Return type:	dict[str, DataSpec]

equals(other)¶

Structural equality of models.

Parameters:	other (HasProps) – the other instance to compare to
Returns:	True, if properties are structurally equal, otherwise False

js_on_change(event, *callbacks)¶

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)

layout(side, plot)¶

classmethod lookup(name)¶

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

Parameters:	name (str) – name of the property to search for
Returns:	descriptor for property named name
Return type:	PropertyDescriptor

on_change(attr, *callbacks)¶

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)

classmethod properties(with_bases=True)¶

Collect the names of properties on this class.

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

Parameters:	with_bases (bool, optional) – Whether to include properties defined on parent classes in the results. (default: True)
Returns:	property names
Return type:	set[str]

classmethod properties_containers()¶

Collect the names of all container properties on this class.

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

Returns:	names of container properties
Return type:	set[str]

classmethod properties_with_refs()¶

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=True)¶

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, include_defaults=True)¶

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()¶

Returns all Models that this object has references to.

remove_on_change(attr, *callbacks)¶

Remove a callback from this object

select(selector)¶

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)¶

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, json, models=None, setter=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, updates)¶

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

Parameters:	selector (JSON-like) – updates (dict) –
Returns:	None

themed_values()¶

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_json(include_defaults)¶

Returns a dictionary of the attributes of this object, containing only “JSON types” (string, number, boolean, none, dict, list).

References to other objects are serialized as “refs” (just the object ID and type info), so the deserializer will need to separately have the full attributes of those other objects.

There’s no corresponding from_json() because to deserialize an object is normally done in the context of a Document (since the Document can resolve references).

For most purposes it’s best to serialize and deserialize entire documents.

Parameters:	include_defaults (bool) – whether to include attributes that haven’t been changed from the default

to_json_string(include_defaults)¶

Returns a JSON string encoding the attributes of this object.

References to other objects are serialized as references (just the object ID and type info), so the deserializer will need to separately have the full attributes of those other objects.

There’s no corresponding from_json_string() because to deserialize an object is normally done in the context of a Document (since the Document can resolve references).

For most purposes it’s best to serialize and deserialize entire documents.

Parameters:	include_defaults (bool) – whether to include attributes that haven’t been changed from the default

trigger(attr, old, new, hint=None, setter=None)¶

unapply_theme()¶

Remove any themed values and restore defaults.

Returns:	None

update(**kwargs)¶

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)

update_from_json(json_attributes, models=None, setter=None)¶

Updates the object’s properties from a JSON attributes dictionary.

Parameters:

json_attributes – (JSON-dict) : attributes and values to update 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

document¶

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

ref¶

A Bokeh protocol “reference” to this model, i.e. a dict of the form:

{
    'type' : << view model name >>
    'id'   : << unique model id >>
}

Additionally there may be a subtype field if this model is a subtype.