dominance_frontiers¶

dominance_frontiers(G, start)[source]¶

Returns the dominance frontiers of all nodes of a directed graph.

Parameters

Ga DiGraph or MultiDiGraph: The graph where dominance is to be computed.
startnode: The start node of dominance computation.

Returns

dfdict keyed by nodes: A dict containing the dominance frontiers of each node reachable from start as lists.

Raises

NetworkXNotImplemented: If G is undirected.
NetworkXError: If start is not in G.

References

1: K. D. Cooper, T. J. Harvey, and K. Kennedy. A simple, fast dominance algorithm. Software Practice & Experience, 4:110, 2001.

Examples

>>> G = nx.DiGraph([(1, 2), (1, 3), (2, 5), (3, 4), (4, 5)])
>>> sorted((u, sorted(df)) for u, df in nx.dominance_frontiers(G, 1).items())
[(1, []), (2, [5]), (3, [5]), (4, [5]), (5, [])]