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

networkx.algorithms.core.k_corona

k_corona(G, k, core_number=None)[source]

Returns the k-corona of G.

The k-corona is the subgraph of nodes in the k-core which have exactly k neighbours in the k-core.

Parameters:
  • G (NetworkX graph) – A graph or directed graph
  • k (int) – The order of the corona.
  • core_number (dictionary, optional) – Precomputed core numbers for the graph G.
Returns:

G – The k-corona subgraph

Return type:

NetworkX graph

Raises:

NetworkXError – The k-cornoa is not defined for graphs with self loops or parallel edges.

Notes

Not implemented for graphs with parallel edges or self loops.

For directed graphs the node degree is defined to be the in-degree + out-degree.

Graph, node, and edge attributes are copied to the subgraph.

See also

core_number()

References

[1]k -core (bootstrap) percolation on complex networks: Critical phenomena and nonlocal effects, A. V. Goltsev, S. N. Dorogovtsev, and J. F. F. Mendes, Phys. Rev. E 73, 056101 (2006) http://link.aps.org/doi/10.1103/PhysRevE.73.056101