isPointed -- checks if a Cone or Fan is pointed

Synopsis

• Usage:

  b = isPointed C

  b = isPointed F

• Inputs:
  • C, a convex rational cone
  • F, an instance of the type Fan
• Outputs:
  • b, a Boolean value, true if the Cone or the Fan is pointed, false otherwise

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 = coneFromHData(matrix{{1,1,-1},{-1,-1,-1}})

o1 = C

o1 : Cone

i2 : isPointed C

o2 = false

i3 : C = intersection{C, coneFromHData(matrix{{1,-1,-1}})}

o3 = C

o3 : Cone

i4 : isPointed C

o4 = true