ApCoCoA-1:NC.IsGB

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Revision as of 12:17, 19 July 2010 by 132.231.10.60 (talk)

NC.IsGB

Check if a list of polynomials is a Groebner basis.

Syntax

NC.IsGB(Polynomials:LIST):BOOL

Description

Please note: The function(s) explained on this page is/are using the ApCoCoAServer. You will have to start the ApCoCoAServer in order to use it/them.

  • Before calling the function, please set ring environment coefficient field K, alphabet X and ordering through the functions NC.SetFp(Prime) (or NC.UnsetFp()), NC.SetX(X) and NC.SetOrdering(Ordering) respectively. Default coefficient field is Q. Default ordering is length-lexicographic ordering ("LLEX"). For more information, please check the relevant functions.

  • @param Polynomials: a LIST of polynomials in K<X>. Each polynomial in K<X> is represented as a LIST of LISTs, which are pairs of form [c, w] where c is in K and w is a word in X*. Unit in X* is empty word represented as an empty STRING "". 0 polynomial is represented as an empty LIST []. For example, polynomial F:=xy-y+1 in K<x,y> is represented as F:=[[1,"xy"], [-1, "y"], [1,""]].

  • @return: a BOOL which is True if Polynomials is a GB and False otherwise.

Example

NC.SetX(<quotes>xyt</quotes>); 
NC.SetOrdering(<quotes>LLEX</quotes>); 
F1 := [[1,<quotes>xx</quotes>], [-1,<quotes>yx</quotes>]];   
F2 := [[1,<quotes>xy</quotes>], [-1,<quotes>ty</quotes>]];  
F3 := [[1,<quotes>xt</quotes>], [-1, <quotes>tx</quotes>]];  
F4 := [[1,<quotes>yt</quotes>], [-1, <quotes>ty</quotes>]];  
Polynomials := [F1, F2,F3,F4]; 
NC.IsGB(Polynomials);
False
-------------------------------
NC.SetOrdering(<quotes>ELIM</quotes>);
NC.IsGB(Polynomials);
False
-------------------------------

See also

NC.Add

NC.GB

NC.LC

NC.LT

NC.LTIdeal

NC.MinimalPolymonial

NC.Multiply

NC.NR

NC.SetFp

NC.SetOrdering

NC.SetRelations

NC.SetRules

NC.SetX

NC.Subtract

NC.UnsetFp

NC.UnsetOrdering

NC.UnsetRelations

NC.UnsetRules

NC.UnsetX

Gbmr.MRSubtract

Gbmr.MRMultiply

Gbmr.MRBP

Gbmr.MRIntersection

Gbmr.MRKernelOfHomomorphism

Gbmr.MRMinimalPolynomials

Introduction to CoCoAServer