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NautyGraphs :: newEdges

newEdges -- replaces disjoint pairs of edges by disjoint pairs of two-chains

Synopsis

Description

The list of "new edge" graphs are formed as follows: Let ab and cd be disjoint edges of G. Then the associated "new edge" graph H is G with the edges ab and cd removed, the vertices e and f added, and the new edges ae, be, cf, df, and ef added.

i1 : newEdges graph {{a,b},{c,d}}

o1 = {Graph{0 => {4}      }}
            1 => {4}
            2 => {5}
            3 => {5}
            4 => {0, 1, 5}
            5 => {4, 2, 3}

o1 : List

If the List input format is used, then one should use care as the list may contain isomorphic pairs.

Ways to use newEdges :