boundary_expansion

boundary_expansion(G, S)

Returns the boundary expansion of the set S.

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

Parameters:

GNetworkX graph

Scollection

A collection of nodes in G.

Returns:

number

The boundary expansion of the set S.

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. <https://doi.org/10.1561/0400000010>

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Additional backends implement this function

graphblas : OpenMP-enabled sparse linear algebra backend.