Home Online Manual
Top
Back: elim1
Forward: nselect
FastBack:
FastForward:
Up: elim_lib
Top: Singular Manual
Contents: Table of Contents
Index: Index
About: About this document

D.4.7.5 elim2

Procedure from library elim.lib (see elim_lib).

Usage:
elim2(id,v); id ideal/module, v intvec

Returns:
ideal/module obtained from id by eliminating variables in v

Note:
no special monomial ordering is required, result is a SB with respect to ordering dp (resp. ls) if the first var not to be eliminated belongs to a -p (resp. -s) blockordering
This proc uses 'execute' or calls a procedure using 'execute'.

Example:
 
LIB "elim.lib";
ring r=0,(x,y,u,v,w),dp;
ideal i=x-u,y-u2,w-u3,v-x+y3;
elim2(i,3..4);
==> _[1]=y2-xw
==> _[2]=xy-w
==> _[3]=x2-y
module m=i*gen(1)+i*gen(2);
m=elim2(m,3..4);show(m);
==> // module, 6 generator(s)
==> [y2-xw]
==> [0,y2-xw]
==> [xy-w]
==> [0,xy-w]
==> [x2-y]
==> [0,x2-y]
See also: elim; elim1; eliminate.