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# networkx.algorithms.shortest_paths.weighted.single_source_dijkstra_path¶

single_source_dijkstra_path(G, source, cutoff=None, weight='weight')[source]

Find shortest weighted paths in G from a source node.

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

Parameters: G (NetworkX graph) source (node) – Starting node for path. cutoff (integer or float, optional) – Depth to stop the search. Only return paths with length <= cutoff. weight (string or function) – 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. paths – Dictionary of shortest path lengths keyed by target. dictionary NodeNotFound – If source is not in G.

Examples

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


Notes

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

The weight function can be used to hide edges by returning None. So weight = lambda u, v, d: 1 if d['color']=="red" else None will find the shortest red path.