Warning

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

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

References

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