networkx.algorithms.shortest_paths.weighted.single_source_bellman_ford_path_length

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

Compute the shortest path length between source and all other reachable nodes for a weighted graph.

Parameters
GNetworkX graph
sourcenode label

Starting node for path

weight: string, optional (default=’weight’)

Edge data key corresponding to the edge weight.

Returns
lengthiterator

(target, shortest path length) iterator

Raises
NodeNotFound

If source is not in G.

Notes

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

Examples

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