Source code for bokeh.plotting.graph

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# Copyright (c) 2012 - 2021, Anaconda, Inc., and Bokeh Contributors.
# All rights reserved.
#
# The full license is in the file LICENSE.txt, distributed with this software.
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# Boilerplate
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from __future__ import annotations

import logging # isort:skip
log = logging.getLogger(__name__)

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# Imports
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# Bokeh imports
from ..models.graphs import StaticLayoutProvider
from ..models.renderers import GraphRenderer

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# Globals and constants
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__all__ = (
    'from_networkx'
)

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# General API
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[docs]def from_networkx(graph, layout_function, **kwargs): ''' Generate a ``GraphRenderer`` from a ``networkx.Graph`` object and networkx layout function. Any keyword arguments will be passed to the layout function. Only two dimensional layouts are supported. Args: graph (networkx.Graph) : a networkx graph to render layout_function (function or dict) : a networkx layout function or mapping of node keys to positions. The position is a two element sequence containing the x and y coordinate. Returns: instance (GraphRenderer) .. note:: Node and edge attributes may be lists or tuples. However, a given attribute must either have *all* lists or tuple values, or *all* scalar values, for nodes or edges it is defined on. .. warning:: Node attributes labeled 'index' and edge attributes labeled 'start' or 'end' are ignored. If you want to convert these attributes, please re-label them to other names. Raises: ValueError ''' # Handles nx 1.x vs 2.x data structure change # Convert node attributes node_dict = dict() node_attr_keys = [attr_key for node in list(graph.nodes(data=True)) for attr_key in node[1].keys()] node_attr_keys = list(set(node_attr_keys)) for attr_key in node_attr_keys: values = [node_attr[attr_key] if attr_key in node_attr.keys() else None for _, node_attr in graph.nodes(data=True)] values = _handle_sublists(values) node_dict[attr_key] = values if 'index' in node_attr_keys: from warnings import warn warn("Converting node attributes labeled 'index' are skipped. " "If you want to convert these attributes, please re-label with other names.") node_dict['index'] = list(graph.nodes()) # Convert edge attributes edge_dict = dict() edge_attr_keys = [attr_key for edge in graph.edges(data=True) for attr_key in edge[2].keys()] edge_attr_keys = list(set(edge_attr_keys)) for attr_key in edge_attr_keys: values = [edge_attr[attr_key] if attr_key in edge_attr.keys() else None for _, _, edge_attr in graph.edges(data=True)] values = _handle_sublists(values) edge_dict[attr_key] = values if 'start' in edge_attr_keys or 'end' in edge_attr_keys: from warnings import warn warn("Converting edge attributes labeled 'start' or 'end' are skipped. " "If you want to convert these attributes, please re-label them with other names.") edge_dict['start'] = [x[0] for x in graph.edges()] edge_dict['end'] = [x[1] for x in graph.edges()] graph_renderer = GraphRenderer() graph_renderer.node_renderer.data_source.data = node_dict graph_renderer.edge_renderer.data_source.data = edge_dict if callable(layout_function): graph_layout = layout_function(graph, **kwargs) else: graph_layout = layout_function node_keys = graph_renderer.node_renderer.data_source.data['index'] if set(node_keys) != set(layout_function.keys()): from warnings import warn warn("Node keys in 'layout_function' don't match node keys in the graph. " "These nodes may not be displayed correctly.") graph_renderer.layout_provider = StaticLayoutProvider(graph_layout=graph_layout) return graph_renderer
#----------------------------------------------------------------------------- # Dev API #----------------------------------------------------------------------------- #----------------------------------------------------------------------------- # Private API #----------------------------------------------------------------------------- def _handle_sublists(values): # if any of the items is non-scalar, they all must be if any(isinstance(x, (list, tuple)) for x in values): if not all(isinstance(x, (list, tuple)) for x in values if x is not None): raise ValueError("Can't mix scalar and non-scalar values for graph attributes") return [[] if x is None else list(x) for x in values] return values #----------------------------------------------------------------------------- # Code #-----------------------------------------------------------------------------