D.4.18.10 locAtZero

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

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