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networkx.algorithms.dominance.dominance_frontiers

dominance_frontiers(G, start)[source]

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

Parameters:
  • G (a DiGraph or MultiDiGraph) – The graph where dominance is to be computed.
  • start (node) – The start node of dominance computation.
Returns:

df – A dict containing the dominance frontiers of each node reachable from start as lists.
Return type:

dict keyed by nodes
Raises:
  • NetworkXNotImplemented – If G is undirected.
  • NetworkXError – If start is not in G.

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, [])]

References

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