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Polyhedra :: incompCones

incompCones -- returns the pairs of incompatible cones

Synopsis

Description

If incompCones is applied to a list of cones and fans, then it returns the pairs of elements whose intersection is not a face of each. For a cone C and a fan F in the list this means there is at least one generating cone of F whose intersection with C is not a face of each. For two fans in the list this means there is at least one generating cone each such that their intersection is not a face of each. If applied to a pair consisting of a cone and a fan or two fans, then it returns the pairs of cones that do not share a common face.

i1 : C1 = coneFromVData matrix{{1,0},{1,1}};
i2 : C2 = coneFromVData matrix{{1,0},{0,-1}};
i3 : C3 = coneFromVData matrix{{-1,0},{0,1}};
i4 : C4 = coneFromVData matrix{{1,1},{0,1}};
i5 : C5 = coneFromVData matrix {{1,2},{2,1}};
i6 : L = {C1,C2,C3,C4,C5};
i7 : Lpairs = incompCones L

o7 = {(C1, C5), (C4, C5)}

o7 : List
i8 : Lpairs == {(C1,C4),(C1,C5)}

o8 = false

Ways to use incompCones :

For the programmer

The object incompCones is a method function.