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statePolytope(ZZ,Ideal) -- computes the mth state polytope of an ideal

Synopsis

Description

See Sturmfels's book Groebner bases and convex polytopes, page 14 for the definition of Statem(I). (The difference between this and State(I) is that for all sufficiently large m, Statem(I) does not distinguish between initial ideals which have the same saturation with regard to the irrelevant ideal, whereas in State(I), these are separated.)
i1 : R = QQ[a..d];
i2 : I = ideal(a*c-b^2,a*d-b*c,b*d-c^2);

o2 : Ideal of R
i3 : statePolytope(3,I)   
LP algorithm being used: "cddgmp".
polymake: used package cddlib
 Implementation of the double description method of Motzkin et al.
 Copyright by Komei Fukuda.
 http://www.ifor.math.ethz.ch/~fukuda/cdd_home/cdd.html

VERTICES
1 9 6 6 9
1 9 3 12 6
1 7 5 14 4
1 5 8 14 3
1 3 12 12 3
1 6 12 3 9
1 4 14 5 7
1 3 14 8 5


o3 = {{9, 6, 6, 9}, {9, 3, 12, 6}, {7, 5, 14, 4}, {5, 8, 14, 3}, {3, 12, 12,
     ------------------------------------------------------------------------
     3}, {6, 12, 3, 9}, {4, 14, 5, 7}, {3, 14, 8, 5}}

o3 : List