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Matroids :: restriction

restriction -- restriction to subset of matroid

Synopsis

Description

The restriction of M to S, M | S, has ground set S and independent sets equal to the independent sets of M contained in S.

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

o1 = a matroid of rank 2 on 4 elements

o1 : Matroid
i2 : N = M | {a,b,d}

o2 = a matroid of rank 2 on 3 elements

o2 : Matroid
i3 : peek N

o3 = Matroid{bases => {set {0, 1}}       }
             cache => CacheTable{...2...}
             groundSet => set {0, 1, 2}
             rank => 2
i4 : N == M | set{0,1,3}

o4 = true

See also

Ways to use restriction :

For the programmer

The object restriction is a method function.