Home Online Manual
Top
Back: makeLetterplaceRing
Forward: lieBracket
FastBack:
FastForward:
Up: freegb_lib
Top: Singular Manual
Contents: Table of Contents
Index: Index
About: About this document

7.10.4.8 letplaceGBasis

Procedure from library freegb.lib (see freegb_lib).

Usage:
letplaceGBasis(I); I an ideal/module

Return:
ideal/module

Assume:
basering is a Letterplace ring, input consists of Letterplace polynomials

Purpose:
compute the two-sided Groebner basis of I via Letterplace algorithm (legacy routine)

Note:
the degree bound for this computation is read off the letterplace structure of basering

Example:
 
LIB "freegb.lib";
ring r = 0,(x,y,z),Dp;
int degree_bound = 5;
def R = freeAlgebra(r, 5);
setring R;
ideal I = -x*y-7*y*y+3*x*x, x*y*x-y*x*y;
ideal J = letplaceGBasis(I);
J;
==> J[1]=3*x*x-x*y-7*y*y
==> J[2]=22*x*y*y-3*y*x*y-21*y*y*x+7*y*y*y
==> J[3]=3*x*y*x-22*x*y*y+21*y*y*x-7*y*y*y
==> J[4]=22803*y*y*y*x+19307*y*y*y*y
==> J[5]=1933*y*y*x*y+2751*y*y*y*x+161*y*y*y*y
==> J[6]=y*y*y*y*y