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This documents an unmaintained version of NetworkX. Please upgrade to a maintained version and see the current NetworkX documentation.
single_source_dijkstra¶

single_source_dijkstra
(G, source, target=None, cutoff=None, weight='weight')[source]¶ Compute shortest paths and lengths in a weighted graph G.
Uses Dijkstra’s algorithm for shortest paths.
Parameters:  G (NetworkX graph) –
 source (node label) – Starting node for path
 target (node label, optional) – Ending node for path
 cutoff (integer or float, optional) – Depth to stop the search. Only paths of length <= cutoff are returned.
Returns: distance,path – Returns a tuple of two dictionaries keyed by node. The first dictionary stores distance from the source. The second stores the path from the source to that node.
Return type: dictionaries
Examples
>>> G=nx.path_graph(5) >>> length,path=nx.single_source_dijkstra(G,0) >>> print(length[4]) 4 >>> print(length) {0: 0, 1: 1, 2: 2, 3: 3, 4: 4} >>> path[4] [0, 1, 2, 3, 4]
Edge weight attributes must be numerical. Distances are calculated as sums of weighted edges traversed.
Based on the Python cookbook recipe (119466) at http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/119466
This algorithm is not guaranteed to work if edge weights are negative or are floating point numbers (overflows and roundoff errors can cause problems).