Ticket #13229 (closed enhancement: fixed)
Adding `DegNegLex` to TermOrder
|Reported by:||AlexanderDreyer||Owned by:||AlexanderDreyer|
|Cc:||burcin, malb, PolyBoRi||Work issues:|
|Report Upstream:||None of the above - read trac for reasoning.||Reviewers:||Martin Albrecht|
|Authors:||Alexander Dreyer||Merged in:||sage-5.3.beta0|
Description (last modified by AlexanderDreyer) (diff)
The attached patch adds the Degree Negative Lexicographical term order (DegNegLex) to Sage 5.1.
It is defined as follows: xa < xb if and only if deg(xa) < deg(xb) or deg(xa) = deg(xb) and there exists 1 <= i <= n such that a1 = b 1 , ... , a i-1 = b i-1, ..., ai > bi.
It is a native term ordering of PolyBoRi ("dp_asc") which Sage does not support yet. But Sage uses it internally to implement DegRevLex-ordered BooleanPolynomialRings by reverting .gens(). It is useful for Sage to distinguish between the original dp_asc and DegRevLex. It will help to fix some design issues discovered when fixing #13202.
Singular supports this as (a(1:n),ls(n)). The patch also includes the patches for the interfaces libSingular and Singular-pexpect.
- Apply: degneglex.patch
comment:10 Changed 10 months ago by malb
- Status changed from needs_review to positive_review
- Reviewers set to Martin Albrecht