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Polyhedra :: dualCone

dualCone -- computes the dual Cone

Synopsis

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 = coneFromVData matrix {{1,2},{2,1}}

o1 = C

o1 : Cone
i2 : Cv = dualCone C

o2 = Cv

o2 : Cone
i3 : rays Cv

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

              2        2
o3 : Matrix ZZ  <--- ZZ

Ways to use dualCone :

For the programmer

The object dualCone is a method function.