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D.13.2.21 gorensteinIndex

Procedure from library polymake.lib (see polymake_lib).

Usage:
gorensteinIndex(p); p polytope

Assume:
isGorenstein(p)==1

Return:
int, a factor n such that n*p+v is reflexive for some translation v

Note:
the translation v can be computed via gorensteinVector(p)

Example:
 
LIB "polymake.lib";
==> Welcome to polymake version
==> Copyright (c) 1997-2015
==> Ewgenij Gawrilow, Michael Joswig (TU Darmstadt)
==> http://www.polymake.org
intmat M[4][3]=1,1,0, 1,0,1, 1,0,0, 1,1,1;
polytope p = polytopeViaPoints(M);
gorensteinIndex(p);
==> polymake: used package ppl
==>   The Parma Polyhedra Library (PPL): A C++ library for convex polyhedra
==>   and other numerical abstractions.
==>   http://www.cs.unipr.it/ppl/
==> 
==> 2