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Matroids :: linearSubclass(...,CheckWellDefined=>...)

linearSubclass(...,CheckWellDefined=>...) -- check whether the list is a modular cut

Synopsis

Description

This option is provided by the package Matroids.

When producing the linear subclass of a matroid M corresponding to a list of flats K, setting this option to true calls isModularCut to check that the list K is in fact a modular cut.

i1 : A = matrix {{1, 0, 0, 1, 1}, {0, 1, 0, 1, -1}, {0, 0, 1, 0, 0}}

o1 = | 1 0 0 1 1  |
     | 0 1 0 1 -1 |
     | 0 0 1 0 0  |

              3        5
o1 : Matrix ZZ  <--- ZZ
i2 : M = matroid A

o2 = a "matroid" of rank 3 on 5 elements

o2 : Matroid
i3 : K = {{2}, {2, 4}, {2, 3}, {1, 2}, {0, 2}, {0, 1, 2, 3, 4}};
i4 : linearSubclass(M, K, CheckWellDefined => true)

o4 = {set {0, 2}, set {2, 4}, set {1, 2}, set {2, 3}}

o4 : List

Further information

See also

Functions with optional argument named CheckWellDefined :