# isSubset(Ideal,Ideal) -- whether one object is a subset of another

## Synopsis

• Function: isSubset
• Usage:
isSubset(I,J)
• Inputs:
• Outputs:
• , whether I is contained in J

## Description

 i1 : R = QQ[a..d]; i2 : I = ideal(a^2-b*c-1,a*c-1,b^3-1); o2 : Ideal of R i3 : isSubset(I^2,I) o3 = true i4 : isSubset(I,I^2) o4 = false
In polynomial rings, this is accomplished by computing a Gröbner basis of J and testing whether every element of I reduces to 0 modulo I.