Return an undirected copy of the graph.
G : Graph/MultiGraph
A deepcopy of the graph.
This returns a “deepcopy” of the edge, node, and graph attributes which attempts to completely copy all of the data and references.
This is in contrast to the similar G=DiGraph(D) which returns a shallow copy of the data.
See the Python copy module for more information on shallow and deep copies, http://docs.python.org/library/copy.html.
>>> G = nx.Graph() # or MultiGraph, etc >>> G.add_path([0,1]) >>> H = G.to_directed() >>> H.edges() [(0, 1), (1, 0)] >>> G2 = H.to_undirected() >>> G2.edges() [(0, 1)]