Attributes such as weights, labels, colors, or whatever Python object you like, can be attached to graphs, nodes, or edges.

Each graph, node, and edge can hold key/value attribute pairs in an associated attribute dictionary (the keys must be hashable). By default these are empty, but attributes can be added or changed using add_edge, add_node or direct manipulation of the attribute dictionaries named G.graph, G.nodes, and G.edges for a graph G.

6.1 Graph attributes

Assign graph attributes when creating a new graph

G = nx.Graph(day="Friday")
G.graph

Or you can modify attributes later

G.graph['day'] = "Monday"
G.graph

6.2 Node attributes

Add node attributes using add_node(), add_nodes_from(), or G.nodes

G.add_node(1, time='5pm')
G.add_nodes_from([3], time='2pm')
G.nodes[1]

G.nodes[1]['room'] = 714
G.nodes.data()

提示

Note that adding a node to G.nodes does not add it to the graph, use G.add_node() to add new nodes. Similarly for edges.

6.3 Edge Attributes

Add/change edge attributes using add_edge(), add_edges_from(), or subscript notation.

G.add_edge(1, 2, weight=4.7 )
G.add_edges_from([(3, 4), (4, 5)], color='red')
G.add_edges_from([(1, 2, {'color': 'blue'}), (2, 3, {'weight': 8})])
G[1][2]['weight'] = 4.7
G.edges[3, 4]['weight'] = 4.2

The special attribute weight should be numeric as it is used by algorithms requiring weighted edges.