This documents an unmaintained version of NetworkX. Please upgrade to a maintained version and see the current NetworkX documentation.


dfs_labeled_edges(G, source=None)[source]

Produce edges in a depth-first-search (DFS) labeled by type.

Parameters :

G : NetworkX graph

source : node, optional

Specify starting node for depth-first search and return edges in the component reachable from source.

Returns :

edges: generator

A generator of edges in the depth-first-search labeled with ‘forward’, ‘nontree’, and ‘reverse’.


Based on http://www.ics.uci.edu/~eppstein/PADS/DFS.py by D. Eppstein, July 2004.

If a source is not specified then a source is chosen arbitrarily and repeatedly until all components in the graph are searched.


>>> G = nx.Graph()
>>> G.add_path([0,1,2])
>>> edges = (list(nx.dfs_labeled_edges(G,0)))