Singular

7.7.12.0. CentralSaturation

Usage:

CentralSaturation(M, T), for a module M and an ideal T

Assume:

T is an ideal in the center of the base ring

Return:

module

Purpose:

compute the central saturation of M by T, that is M:T^{\infty}, by repititive application of CentralQuot

Note:

the output module is not necessarily a Groebner basis

LIB "ncdecomp.lib";
option(returnSB);
def a = makeUsl2();
setring a;
ideal I = e3,f3,h3-4*h;
I = std(I);
poly C=4*e*f+h^2-2*h;
ideal G = C*(C-8);
ideal R = CentralSaturation(I,G);
R=std(R);
vdim(R);
==> 5
R;
==> R[1]=h
==> R[2]=ef-6
==> R[3]=f3
==> R[4]=e3