single_source_dijkstra_path(G, source, cutoff=None, weight='weight')¶
Find shortest weighted paths in G from a source node.
Compute shortest path between source and all other reachable nodes for a weighted graph.
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
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.
- Return type
NodeNotFound – If
sourceis not in
>>> G = nx.path_graph(5) >>> path = nx.single_source_dijkstra_path(G, 0) >>> path [0, 1, 2, 3, 4]
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 Nonewill find the shortest red path.