Note

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

networkx.algorithms.shortest_paths.weighted.all_pairs_bellman_ford_path_length

all_pairs_bellman_ford_path_length(G, weight='weight')[source]

Compute shortest path lengths between all nodes in a weighted graph.

Parameters
GNetworkX graph
weight: string, optional (default=’weight’)

Edge data key corresponding to the edge weight

Returns
distanceiterator

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

Notes

Edge weight attributes must be numerical. Distances are calculated as sums of weighted edges traversed.

The dictionary returned only has keys for reachable node pairs.

Examples

>>> G = nx.path_graph(5)
>>> length = dict(nx.all_pairs_bellman_ford_path_length(G))
>>> for node in [0, 1, 2, 3, 4]:
...     print(f"1 - {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