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networkx.algorithms.cuts.boundary_expansion

boundary_expansion(G, S)[source]

Returns the boundary expansion of the set S.

The boundary expansion is the quotient of the size of the edge boundary and the cardinality of S. [1]

Parameters:
  • G (NetworkX graph)
  • S (sequence) – A sequence of nodes in G.
Returns:

The boundary expansion of the set S.
Return type:

number

See also

edge_expansion(), mixing_expansion(), node_expansion()

References

[1]Vadhan, Salil P. “Pseudorandomness.” Foundations and Trends in Theoretical Computer Science 7.1–3 (2011): 1–336. <http://dx.doi.org/10.1561/0400000010>