Note

This documents the development version of NetworkX. Documentation for the current release can be found here.

networkx.Graph.edges

property Graph.edges

An EdgeView of the Graph as G.edges or G.edges().

edges(self, nbunch=None, data=False, default=None)

The EdgeView provides set-like operations on the edge-tuples as well as edge attribute lookup. When called, it also provides an EdgeDataView object which allows control of access to edge attributes (but does not provide set-like operations). Hence, G.edges[u, v]['color'] provides the value of the color attribute for edge (u, v) while for (u, v, c) in G.edges.data('color', default='red'): iterates through all the edges yielding the color attribute with default 'red' if no color attribute exists.

Parameters
nbunchsingle node, container, or all nodes (default= all nodes)

The view will only report edges incident to these nodes.

datastring or bool, optional (default=False)

The edge attribute returned in 3-tuple (u, v, ddict[data]). If True, return edge attribute dict in 3-tuple (u, v, ddict). If False, return 2-tuple (u, v).

defaultvalue, optional (default=None)

Value used for edges that don’t have the requested attribute. Only relevant if data is not True or False.

Returns
edgesEdgeView

A view of edge attributes, usually it iterates over (u, v) or (u, v, d) tuples of edges, but can also be used for attribute lookup as edges[u, v]['foo'].

Notes

Nodes in nbunch that are not in the graph will be (quietly) ignored. For directed graphs this returns the out-edges.

Examples

>>> G = nx.path_graph(3)  # or MultiGraph, etc
>>> G.add_edge(2, 3, weight=5)
>>> [e for e in G.edges]
[(0, 1), (1, 2), (2, 3)]
>>> G.edges.data()  # default data is {} (empty dict)
EdgeDataView([(0, 1, {}), (1, 2, {}), (2, 3, {'weight': 5})])
>>> G.edges.data("weight", default=1)
EdgeDataView([(0, 1, 1), (1, 2, 1), (2, 3, 5)])
>>> G.edges([0, 3])  # only edges incident to these nodes
EdgeDataView([(0, 1), (3, 2)])
>>> G.edges(0)  # only edges incident to a single node (use G.adj[0]?)
EdgeDataView([(0, 1)])