Top
Back: isLocallyFree
Forward: hom_kernel
FastBack:
FastForward:
Up: homolog_lib
Top: Singular Manual
Contents: Table of Contents
Index: Index
About: About this document

D.4.8.14 isReg

Procedure from library homolog.lib (see homolog_lib).

Usage:
isReg(I,M); I ideal, M module

Return:
1 if given (ordered) list of generators for I is coker(M)-sequence;
0 if this is not the case.

Example:
 
LIB "homolog.lib";
ring R = 0,(x,y,z),dp;
ideal I = x*(y-1),y,z*(y-1);
isReg(I,0);             // given list of generators is Q[x,y,z]-sequence
==> 1
I = x*(y-1),z*(y-1),y;  // change sorting of generators
isReg(I,0);
==> 0
ring r = 0,(x,y,z),ds;  // local ring
ideal I=fetch(R,I);
isReg(I,0);             // result independent of sorting of generators
==> 1


Top Back: isLocallyFree Forward: hom_kernel FastBack: FastForward: Up: homolog_lib Top: Singular Manual Contents: Table of Contents Index: Index About: About this document
            User manual for Singular version 4-0-3, 2016, generated by texi2html.