all_simple_paths¶

all_simple_paths
(G, source, target, cutoff=None)[source]¶ Generate all simple paths in the graph G from source to target.
A simple path is a path with no repeated nodes.
Parameters:  G (NetworkX graph) –
 source (node) – Starting node for path
 target (node) – Ending node for path
 cutoff (integer, optional) – Depth to stop the search. Only paths of length <= cutoff are returned.
Returns: path_generator – A generator that produces lists of simple paths. If there are no paths between the source and target within the given cutoff the generator produces no output.
Return type: generator
Examples
>>> G = nx.complete_graph(4) >>> for path in nx.all_simple_paths(G, source=0, target=3): ... print(path) ... [0, 1, 2, 3] [0, 1, 3] [0, 2, 1, 3] [0, 2, 3] [0, 3] >>> paths = nx.all_simple_paths(G, source=0, target=3, cutoff=2) >>> print(list(paths)) [[0, 1, 3], [0, 2, 3], [0, 3]]
Notes
This algorithm uses a modified depthfirst search to generate the paths [1]. A single path can be found in time but the number of simple paths in a graph can be very large, e.g. in the complete graph of order n.
References
[1] R. Sedgewick, “Algorithms in C, Part 5: Graph Algorithms”, Addison Wesley Professional, 3rd ed., 2001. See also
all_shortest_paths()
,shortest_path()