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D.2.8.5 is_zero

Procedure from library poly.lib (see poly_lib).

Usage:
is_zero(M[,any]); M=poly/ideal/vector/module/matrix

Return:
integer, 1 if coker(M)=0 resp. 0 if coker(M)!=0, where M is considered as matrix.
If a second argument is given, return a list:
L[1] = 1 if coker(M)=0 resp. 0 if coker(M)!=0
L[2] = dim(M)

Example:
 
LIB "poly.lib";
ring r;
module m = [x],[y],[1,z];
is_zero(m,1);
==> [1]:
==>    0
==> [2]:
==>    2
qring q = std(ideal(x2+y3+z2));
ideal j = x2+y3+z2-37;
is_zero(j);
==> 1