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OldPolyhedra :: isPointed

isPointed -- checks if a Cone or Fan is pointed

Synopsis

Description

Tests if a Cone is pointed, i.e. the lineality space is 0. A Fan is pointed if one of its Cones is pointed. This is equivalent to all Cones being pointed.

i1 : C = intersection(matrix{{1,1,-1},{-1,-1,-1}})

o1 = {ambient dimension => 3           }
      dimension of lineality space => 1
      dimension of the cone => 3
      number of facets => 2
      number of rays => 2

o1 : Cone
i2 : isPointed C

o2 = false
i3 : C = intersection{C,(matrix{{1,-1,-1}},0)}

o3 = {ambient dimension => 3           }
      dimension of lineality space => 0
      dimension of the cone => 3
      number of facets => 3
      number of rays => 3

o3 : Cone
i4 : isPointed C

o4 = true

Ways to use isPointed :

For the programmer

The object isPointed is a method function.