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dualCone -- computes the dual Cone

Synopsis

Usage:
Cv = dualCone C
Inputs:
- C, a convex rational cone
Outputs:
- Cv, a convex rational cone

Description

The dual cone of C in QQ^n is the cone in the dual ambient space (QQ^n)^*, given by {p in (QQ^n)^* | p*c >= 0 for all c in C}.

i1 : C = posHull matrix {{1,2},{2,1}}

o1 = {ambient dimension => 2           }
      dimension of lineality space => 0
      dimension of the cone => 2
      number of facets => 2
      number of rays => 2

o1 : Cone

i2 : Cv = dualCone C

o2 = {ambient dimension => 2           }
      dimension of lineality space => 0
      dimension of the cone => 2
      number of facets => 2
      number of rays => 2

o2 : Cone

i3 : rays Cv

o3 = | 2  -1 |
     | -1 2  |

              2        2
o3 : Matrix QQ  <--- QQ

Ways to use `dualCone` :

dualCone(Cone)