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apparently wrong monomial order in ToricIdeal? #29832

Open dimpase opened 4 years ago

dimpase commented 4 years ago

It seems that neglex used there isn't the right order, for it's not even a Groebner basis order. See

https://ask.sagemath.org/question/51851/toric-ideal-of-point-configuration-yielding-whole-ring/

for details and an example showing a meaningless answer from Sage. Namely the following is wrong:

sage: A = matrix([[1,0,0,0,-1,-1,-2],[0,1,0,-1,-1,-2,-3]])
....: IA = ToricIdeal(A); IA
....: 
Ideal (1) of Multivariate Polynomial Ring in z0, z1, z2, z3, z4, z5, z6 over Rational Field

IMHO it should be something like degrevlex instead. Or, indeed, Signular provides weighted orders that can be used.

CC: @vbraun

Component: algebraic geometry

Issue created by migration from https://trac.sagemath.org/ticket/29832

mkoeppe commented 3 years ago
comment:2

Moving to 9.4, as 9.3 has been released.