all_pairs_bellman_ford_path

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

Compute shortest paths between all nodes in a weighted graph.

Parameters
GNetworkX graph
weightstring or function (default=”weight”)

If this is a string, then edge weights will be accessed via the edge attribute with this key (that is, the weight of the edge joining u to v will be G.edges[u, v][weight]). If no such edge attribute exists, the weight of the edge is assumed to be one.

If this is a function, the weight of an edge is the value returned by the function. The function must accept exactly three positional arguments: the two endpoints of an edge and the dictionary of edge attributes for that edge. The function must return a number.

Returns
distancedictionary

Dictionary, keyed by source and target, of shortest paths.

See also

floyd_warshall, all_pairs_dijkstra_path

Notes

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

Examples

>>> G = nx.path_graph(5)
>>> path = dict(nx.all_pairs_bellman_ford_path(G))
>>> path[0][4]
[0, 1, 2, 3, 4]