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cartesianProduct -- Computes the cartesian product of two graphs

Synopsis

Description

This method will take in any two graphs and output the cartesian product of the two graphs. The vertex set of this new graph is the cartesian product of the vertex sets of the two input graphs. The keys for each vertex will be output as a sequence. Any two vertices (u,u') and (v,v') are adjacent in the cartesian product of G and H if and only if either u = v and u' is adjacent with v' in H, or u' = v' and u is adjacent with v in G.

i1 : G = graph({1,2},{{1,2}});
i2 : H = graph({3,4,5},{{3,4},{4,5}});
i3 : G' = cartesianProduct(G,H)

o3 = Graph{(1, 3) => {(2, 3), (1, 4)}        }
           (1, 4) => {(1, 3), (2, 4), (1, 5)}
           (1, 5) => {(2, 5), (1, 4)}
           (2, 3) => {(1, 3), (2, 4)}
           (2, 4) => {(2, 5), (2, 3), (1, 4)}
           (2, 5) => {(2, 4), (1, 5)}

o3 : Graph

See also

Ways to use cartesianProduct :

For the programmer

The object cartesianProduct is a method function.