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communicability

communicability(G)[source]

Return communicability between all pairs of nodes in G.

The communicability between pairs of nodes in G is the sum of closed walks of different lengths starting at node u and ending at node v.

Parameters:

G: graph

Returns:

comm: dictionary of dictionaries

Dictionary of dictionaries keyed by nodes with communicability as the value.

Raises:

NetworkXError

If the graph is not undirected and simple.

See also

communicability_centrality_exp
Communicability centrality for each node of G using matrix exponential.
communicability_centrality
Communicability centrality for each node in G using spectral decomposition.
communicability
Communicability between pairs of nodes in G.

Notes

This algorithm uses a spectral decomposition of the adjacency matrix. Let G=(V,E) be a simple undirected graph. Using the connection between the powers of the adjacency matrix and the number of walks in the graph, the communicability between nodes u and v based on the graph spectrum is [R175]

C(u,v)=nj=1ϕj(u)ϕj(v)eλj,

where ϕj(u) is the uth element of the jth orthonormal eigenvector of the adjacency matrix associated with the eigenvalue λj.

References

[R175](1, 2) Ernesto Estrada, Naomichi Hatano, “Communicability in complex networks”, Phys. Rev. E 77, 036111 (2008). http://arxiv.org/abs/0707.0756

Examples

>>> G = nx.Graph([(0,1),(1,2),(1,5),(5,4),(2,4),(2,3),(4,3),(3,6)])
>>> c = nx.communicability(G)