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Polyhedra :: hilbertBasis(Cone)

hilbertBasis(Cone) -- computes the Hilbert basis of a Cone

Synopsis

Description

The Hilbert basis of the cone C is computed by the Project-and-Lift-algorithm by Raymond Hemmecke (see below). It computes a Hilbert basis of the cone modulo the lineality space, so it returns the list of one column matrices that give the Hilbert basis of the Cone if one adds the basis of the lineality space and its negative. For the Project-and-Lift-algorithm see:

Raymond Hemmecke's On the computation of Hilbert bases of cones, in A. M. Cohen, X.-S. Gao, and N. Takayama, editors, Mathematical Software, ICMS 2002, pages 307317. World Scientific, 2002.

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

o1 = C

o1 : Cone
i2 : hilbertBasis C

o2 = {| 1 |, | 2 |, | 1 |}
      | 2 |  | 1 |  | 1 |

o2 : List