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Matroids :: areIsomorphic(Matroid,Matroid)

areIsomorphic(Matroid,Matroid) -- whether two matroids are isomorphic

Synopsis

Description

Two matroids are isomorphic if there is a bijection between their ground sets which induces a bijection between bases, or equivalently, circuits (which is what this package actually checks, since there are often fewer circuits than bases).

This method first runs quickIsomorphismTest, then isomorphism if the tests are inconclusive.

i1 : M = matroid({a,b,c},{{a,b},{a,c},{b,c}})

o1 = a matroid of rank 2 on 3 elements

o1 : Matroid
i2 : areIsomorphic(M, uniformMatroid(2,3))

o2 = true
i3 : M0 = matroid({a,b,c},{{a,b},{a,c}})

o3 = a matroid of rank 2 on 3 elements

o3 : Matroid
i4 : areIsomorphic(M, M0)

o4 = false

Caveat

Isomorphism of matroids should not be confused with equality: cf. == for more details.

See also