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SlackIdeals :: containsFlag

containsFlag -- establishes whether or not a list of facet labels contains a flag in a polytope or matroid

Synopsis

Description

Given a list of facet labels fl and a polytope, a matroid, a (symbolic) slack matrix or a list of vertex coordinates, matroid vectors, facet labels, establishes whether or not fl contains a flag in the given object.

i1 : V = {{0, 0, 0}, {0, 0, 1}, {1, 0, 0}, {1, 0, 1}, {0, 1, 0}, {0, 1, 1}};
i2 : containsFlag({0, 1, 2, 4}, V)

Order of vertices is 
{{0, 0, 0}, {1, 0, 0}, {0, 1, 0}, {0, 0, 1}, {1, 0, 1}, {0, 1, 1}}

o2 = true
i3 : containsFlag({0, 1, 2, 8}, V, Object => "matroid")

o3 = true
i4 : containsFlag({0, 1, 2, 3}, {{0, 2, 3, 5}, {0, 1, 3, 4}, {1, 2, 4, 5}, {0, 1, 2}, {3, 4, 5}}, Object => "abstractPolytope")

o4 = true

See also

Ways to use containsFlag :