Singular Manual: is_zero

| #### D.2.8.5 is_zero Procedure from library `polylib.lib` (see polylib_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 "polylib.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

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