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D.4.25.10 locAtZero

Procedure from library normal.lib (see normal_lib).

Usage:
locAtZero(I); I = ideal

Return:
int, 1 if I has only one point which is located at zero, 0 otherwise

Assume:
I is given as a standard bases in the basering

Note:
only useful in affine rings, in local rings vdim does the check

Example:
 
LIB "normal.lib";
ring r = 0,(x,y,z),dp;
poly f = z5+y4+x3+xyz;
ideal i = jacob(f),f;
i=std(i);
locAtZero(i);
==> 1
i= std(i*ideal(x-1,y,z));
locAtZero(i);
==> 0