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Computes the Ehrhart ring
NmzEhrhartRing(L: LIST of RINGELEM, s: RINGELEM): LIST of RINGELEM |
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, 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.
/**/ 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]
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