bokeh.core.query — Anaconda Enterprise 4.4 documentation

Anaconda Enterprise: Documentation

# bokeh.core.query

The query module provides functions for searching collections of Bokeh models for instances that match specified criteria.

class `bokeh.core.query.` `EQ`

  Predicate to test if property values are equal to some value.

  Construct and `EQ` predicate as a dict with `EQ` as the key, and a value to compare against.

      # matches any models with .size == 10
      dict(size={ EQ: 10 })

class `bokeh.core.query.` `GEQ`

  Predicate to test if property values are greater than or equal to some value.

  Construct and `GEQ` predicate as a dict with `GEQ` as the key, and a value to compare against.

      # matches any models with .size >= 10
      dict(size={ GEQ: 10 })

class `bokeh.core.query.` `GT`

  Predicate to test if property values are greater than some value.

  Construct and `GT` predicate as a dict with `GT` as the key, and a value to compare against.

      # matches any models with .size > 10
      dict(size={ GT: 10 })

class `bokeh.core.query.` `IN`

  Predicate to test if property values are in some collection.

  Construct and `IN` predicate as a dict with `IN` as the key, and a list of values to check against.

      # matches any models with .name in ['a', 'mycircle', 'myline']
      dict(name={ IN: ['a', 'mycircle', 'myline'] })

class `bokeh.core.query.` `LEQ`

  Predicate to test if property values are less than or equal to some value.

  Construct and `LEQ` predicate as a dict with `LEQ` as the key, and a value to compare against.

      # matches any models with .size <= 10
      dict(size={ LEQ: 10 })

class `bokeh.core.query.` `LT`

  Predicate to test if property values are less than some value.

  Construct and `LT` predicate as a dict with `LT` as the key, and a value to compare against.

      # matches any models with .size < 10
      dict(size={ LT: 10 })

class `bokeh.core.query.` `NEQ`

  Predicate to test if property values are unequal to some value.

  Construct and `NEQ` predicate as a dict with `NEQ` as the key, and a value to compare against.

      # matches any models with .size != 10
      dict(size={ NEQ: 10 })

class `bokeh.core.query.` `OR`

  Form disjunctions from other query predicates.

  Construct an `OR` expression by making a dict with `OR` as the key, and a list of other query expressions as the value:

      # matches any Axis subclasses or models with .name == "mycircle"
      { OR: [dict(type=Axis), dict(name="mycircle")] }

`bokeh.core.query.` `find`(objs, selector, context=None)

  Query a collection of Bokeh models and yield any that match the a selector.

  Parameters: | obj (Model) – object to test selector (JSON-like) – query selector context (dict) – kwargs to supply callable query attributes
  Yields: | Model – objects that match the query

  Queries are specified as selectors similar to MongoDB style query selectors, as described for `match()`.

  Examples

      # find all objects with type Grid
      find(p.references(), {'type': Grid})

      # find all objects with type Grid or Axis
      find(p.references(), {OR: [
          {'type': Grid}, {'type': Axis}
      ]})

      # same query, using IN operator
      find(p.references(), {'type': {IN: [Grid, Axis]}})

      # find all plot objects on the 'left' layout of the Plot
      # here layout is a method that takes a plot as context
      find(p.references(), {'layout': 'left'}, {'plot': p})

`bokeh.core.query.` `match`(obj, selector, context=None)

  Test whether a given Bokeh model matches a given selector.

  Parameters: | obj (Model) – object to test selector (JSON-like) – query selector context (dict) – kwargs to supply callable query attributes
  Returns: | True if the object matches, False otherwise
  Return type: | bool

  In general, the selectors have the form:

      { attrname : predicate }

  Where a predicate is constructed from the operators `EQ`, `GT`, etc. and is used to compare against values of model attributes named `attrname`.

  For example:

      >>> from bokeh.plotting import figure
      >>> p = figure(plot_width=400)

      >>> match(p, {'plot_width': {EQ: 400}})
      True

      >>> match(p, {'plot_width': {GT: 500}})
      False

  There are two selector keys that are handled especially. The first is ‘type’, which will do an isinstance check:

      >>> from bokeh.plotting import figure
      >>> from bokeh.models import Axis
      >>> p = figure()

      >>> match(p.xaxis[0], {'type': Axis})
      True

      >>> match(p.title, {'type': Axis})
      False

  There is also a `'tags'` attribute that `Model` objects have, that is a list of user-supplied values. The `'tags'` selector key can be used to query against this list of tags. An object matches if any of the tags in the selector match any of the tags on the object:

      >>> from bokeh.plotting import figure
      >>> p = figure(tags = ["my plot", 10])

      >>> match(p, {'tags': "my plot"})
      True

      >>> match(p, {'tags': ["my plot", 10]})
      True

      >>> match(p, {'tags': ["foo"]})
      False