R igraph manual pages

count_isomorphisms {igraph}

R Documentation

Count the number of isomorphic mappings between two graphs

Description

Count the number of isomorphic mappings between two graphs

Usage

count_isomorphisms(graph1, graph2, method = "vf2", ...)

Arguments

graph1	The first graph.
graph2	The second graph.
method	Currently only ‘vf2’ is supported, see isomorphic for details about it and extra arguments.
...	Passed to the individual methods.

Value

Number of isomorphic mappings between the two graphs.

References

LP Cordella, P Foggia, C Sansone, and M Vento: An improved algorithm for matching large graphs, Proc. of the 3rd IAPR TC-15 Workshop on Graphbased Representations in Pattern Recognition, 149–159, 2001.

See Also

Other graph isomorphism: count_subgraph_isomorphisms(), graph_from_isomorphism_class(), isomorphic(), isomorphism_class(), isomorphisms(), subgraph_isomorphic(), subgraph_isomorphisms()

Examples

# colored graph isomorphism
g1 <- make_ring(10)
g2 <- make_ring(10)
isomorphic(g1, g2)

V(g1)$color <- rep(1:2, length = vcount(g1))
V(g2)$color <- rep(2:1, length = vcount(g2))
# consider colors by default
count_isomorphisms(g1, g2)
# ignore colors
count_isomorphisms(g1, g2, vertex.color1 = NULL,
    vertex.color2 = NULL)

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