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networkx.algorithms.shortest_paths.unweighted.all_pairs_shortest_path_length

all_pairs_shortest_path_length(G, cutoff=None)[source]

Computes the shortest path lengths between all nodes in G.

Parameters:
  • G (NetworkX graph)
  • cutoff (integer, optional) – Depth at which to stop the search. Only paths of length at most cutoff are returned.
Returns:

lengths – (source, dictionary) iterator with dictionary keyed by target and shortest path length as the key value.

Return type:

iterator

Notes

The iterator returned only has reachable node pairs.

Examples

>>> G = nx.path_graph(5)
>>> length = dict(nx.all_pairs_shortest_path_length(G))
>>> for node in [0, 1, 2, 3, 4]:
...     print('1 - {}: {}'.format(node, length[1][node]))
1 - 0: 1
1 - 1: 0
1 - 2: 1
1 - 3: 2
1 - 4: 3
>>> length[3][2]
1
>>> length[2][2]
0