networkx.classes.function.set_node_attributes¶
-
set_node_attributes
(G, values, name=None)[source]¶ Sets node attributes from a given value or dictionary of values.
Warning
The call order of arguments
values
andname
switched between v1.x & v2.x.- Parameters
G (NetworkX Graph)
values (scalar value, dict-like) – What the node attribute should be set to. If
values
is not a dictionary, then it is treated as a single attribute value that is then applied to every node inG
. This means that if you provide a mutable object, like a list, updates to that object will be reflected in the node attribute for every node. The attribute name will bename
.If
values
is a dict or a dict of dict, it should be keyed by node to either an attribute value or a dict of attribute key/value pairs used to update the node’s attributes.name (string (optional, default=None)) – Name of the node attribute to set if values is a scalar.
Examples
After computing some property of the nodes of a graph, you may want to assign a node attribute to store the value of that property for each node:
>>> G = nx.path_graph(3) >>> bb = nx.betweenness_centrality(G) >>> isinstance(bb, dict) True >>> nx.set_node_attributes(G, bb, "betweenness") >>> G.nodes[1]["betweenness"] 1.0
If you provide a list as the second argument, updates to the list will be reflected in the node attribute for each node:
>>> G = nx.path_graph(3) >>> labels = [] >>> nx.set_node_attributes(G, labels, "labels") >>> labels.append("foo") >>> G.nodes[0]["labels"] ['foo'] >>> G.nodes[1]["labels"] ['foo'] >>> G.nodes[2]["labels"] ['foo']
If you provide a dictionary of dictionaries as the second argument, the outer dictionary is assumed to be keyed by node to an inner dictionary of node attributes for that node:
>>> G = nx.path_graph(3) >>> attrs = {0: {"attr1": 20, "attr2": "nothing"}, 1: {"attr2": 3}} >>> nx.set_node_attributes(G, attrs) >>> G.nodes[0]["attr1"] 20 >>> G.nodes[0]["attr2"] 'nothing' >>> G.nodes[1]["attr2"] 3 >>> G.nodes[2] {}