Shortest Paths

Compute the shortest paths and path lengths between nodes in the graph.

These algorithms work with undirected and directed graphs.

shortest_path(G[, source, target, weight]) Compute shortest paths in the graph.
all_shortest_paths(G, source, target[, weight]) Compute all shortest paths in the graph.
shortest_path_length(G[, source, target, weight]) Compute shortest path lengths in the graph.
average_shortest_path_length(G[, weight]) Return the average shortest path length.
has_path(G, source, target) Return True if G has a path from source to target, False otherwise.

Advanced Interface

Shortest path algorithms for unweighted graphs.

single_source_shortest_path(G, source[, cutoff]) Compute shortest path between source and all other nodes reachable from source.
single_source_shortest_path_length(G, source) Compute the shortest path lengths from source to all reachable nodes.
all_pairs_shortest_path(G[, cutoff]) Compute shortest paths between all nodes.
all_pairs_shortest_path_length(G[, cutoff]) Computes the shortest path lengths between all nodes in G.
predecessor(G, source[, target, cutoff, ...]) Returns dictionary of predecessors for the path from source to all nodes in G.

Shortest path algorithms for weighed graphs.

dijkstra_path(G, source, target[, weight]) Returns the shortest path from source to target in a weighted graph G.
dijkstra_path_length(G, source, target[, weight]) Returns the shortest path length from source to target in a weighted graph.
single_source_dijkstra_path(G, source[, ...]) Compute shortest path between source and all other reachable nodes for a weighted graph.
single_source_dijkstra_path_length(G, source) Compute the shortest path length between source and all other reachable nodes for a weighted graph.
all_pairs_dijkstra_path(G[, cutoff, weight]) Compute shortest paths between all nodes in a weighted graph.
all_pairs_dijkstra_path_length(G[, cutoff, ...]) Compute shortest path lengths between all nodes in a weighted graph.
single_source_dijkstra(G, source[, target, ...]) Compute shortest paths and lengths in a weighted graph G.
bidirectional_dijkstra(G, source, target[, ...]) Dijkstra’s algorithm for shortest paths using bidirectional search.
dijkstra_predecessor_and_distance(G, source) Compute shortest path length and predecessors on shortest paths in weighted graphs.
bellman_ford(G, source[, weight]) Compute shortest path lengths and predecessors on shortest paths in weighted graphs.
negative_edge_cycle(G[, weight]) Return True if there exists a negative edge cycle anywhere in G.
johnson(G[, weight]) Compute shortest paths between all nodes in a weighted graph using Johnson’s algorithm.

Dense Graphs

Floyd-Warshall algorithm for shortest paths.

floyd_warshall(G[, weight]) Find all-pairs shortest path lengths using Floyd’s algorithm.
floyd_warshall_predecessor_and_distance(G[, ...]) Find all-pairs shortest path lengths using Floyd’s algorithm.
floyd_warshall_numpy(G[, nodelist, weight]) Find all-pairs shortest path lengths using Floyd’s algorithm.

A* Algorithm

Shortest paths and path lengths using A* (“A star”) algorithm.

astar_path(G, source, target[, heuristic, ...]) Return a list of nodes in a shortest path between source and target using the A* (“A-star”) algorithm.
astar_path_length(G, source, target[, ...]) Return the length of the shortest path between source and target using the A* (“A-star”) algorithm.