k_corona

k_corona(G, k, core_number=None)

Returns the k-corona of G.

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

Deprecated since version 3.3: k_corona will not accept MultiGraph objects in version 3.5.

Parameters:

GNetworkX graph

A graph or directed graph

kint

The order of the corona.

core_numberdictionary, optional

Precomputed core numbers for the graph G.

Returns:

GNetworkX graph

The k-corona subgraph

Raises:

NetworkXNotImplemented

The k-corona is not defined for multigraphs or graphs with self loops.

See also

core_number

Notes

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.

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

Examples

>>> degrees = [0, 1, 2, 2, 2, 2, 3]
>>> H = nx.havel_hakimi_graph(degrees)
>>> H.degree
DegreeView({0: 1, 1: 2, 2: 2, 3: 2, 4: 2, 5: 3, 6: 0})
>>> nx.k_corona(H, k=2).nodes
NodeView((1, 2, 3, 5))