BFS is a workhorse! There are still many BFS-based algorithms still to do.

My main TODO is to benchmark these to give them a proper shakedown. I like to shake down most algorithms we add. Also, I wonder whether we should useA.T orAT in a couple places. I also wonder if we can come up with a heuristic to detect negative cycles.

It may be nice to know whether directed graphs are structurally symmetric. If we knew this, we could improveis_weakly_connected and other algorithms.

Also, there may be a couple NetworkX bugs to fix or behaviors to match.

Implemented:

• Components
  • is_connected
  • is_weakly_connected
  • node_connected_component
• Shortest Paths
  • all_pairs_shortest_path_length
  • negative_edge_cycle
  • single_source_shortest_path_length
  • single_target_shortest_path_length
• Traversal
  • bfs_layers
  • descendants_at_distance