up previous next
HasGBasis

checks if the argument has a pre-computed GBasis

Syntax 
HasGBasis(I: IDEAL): BOOL

Description
After the GBasis of I is (explicitely or implicitely) computed, it is stored within I for future use. This function says whether the GBasis of I has been stored.

Example 
/**/  Use R ::= QQ[x,y,z];
/**/  I := ideal(x^20 -x*y -1, x^10*y^10 -x*z -1,  x^10*z^10 -x*z -1);
/**/  HasGBasis(I);
false
/**/  t0 := CpuTime(); GB := GBasis(I); TimeFrom(t0);
0.948
/**/  HasGBasis(I);
true
/**/  t0 := CpuTime(); GB := GBasis(I); TimeFrom(t0);
0.007