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NmzEhrhartRing

Computes the Ehrhart ring

Syntax
NmzEhrhartRing(L: LIST of RINGELEM, s: RINGELEM): LIST of RINGELEM

Description
The exponent vectors of the given monomials are considered as vertices of a lattice polytope P . The Ehrhart ring of a (lattice) polytope P is the monoid algebra defined by the monoid of lattice points in the cone over the polytope P ; see the book by Bruns and Gubeladze, Polytopes, Rings, and K-theory, publ. Springer 2009, pp. 228--229.

The function returns the generators of the Ehrhart ring. It uses the indeterminate in the second argument as auxiliary indeterminate of the Ehrhart ring.

Example
/**/     use R::=QQ[x,y,z,t];
/**/     NmzEhrhartRing([x^2,y^2,z^3],t);
[x^2*t, z^3*t, x*y*t, y^2*t]

See Also