normalCone(Polyhedron,Polyhedron) -- computes the normal cone of a face of a polyhedron

Synopsis

• Function: normalCone

• Usage:

  C = normalCone(P,Q)

• Inputs:
  • P, a convex polyhedron
  • Q, a convex polyhedron, which must be a face of P
• Optional inputs:
  • BasisElementLimit => ..., default value infinity,
  • DegreeLimit => ..., default value {},
  • MinimalGenerators => ..., default value true,
  • PairLimit => ..., default value infinity,
  • Strategy => ..., default value null,
  • Variable => ..., default value "w",
• Outputs:
  • C, a convex rational cone

Description

i1 : P = hypercube 3

o1 = P

o1 : Polyhedron

i2 : Q = convexHull matrix {{1,1,-1,-1},{1,-1,1,-1},{1,1,1,1}}

o2 = Q

o2 : Polyhedron

i3 : C = normalCone(P,Q)

o3 = C

o3 : Cone

i4 : rays C

o4 = | 0  |
     | 0  |
     | -1 |

              3       1
o4 : Matrix ZZ  <-- ZZ