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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
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]
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See also:
elim;
elim1;
eliminate.
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