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SymbolicPowers :: isSymbolicEqualOrdinary

isSymbolicEqualOrdinary -- tests if symbolic power is equal to ordinary power

Synopsis

Description

Given a radical ideal I and an integer n, this method returns true if and only if In=I(n). This method circumvents computing the symbolic powers in most cases, by first testing the bigHeight of In

i1 : B = QQ[x,y,z];
i2 : f = map(QQ[t],B,{t^3,t^4,t^5})

                   3   4   5
o2 = map(QQ[t],B,{t , t , t })

o2 : RingMap QQ[t] <--- B
i3 : I = ker f;

o3 : Ideal of B
i4 : isSymbolicEqualOrdinary(I,2)

o4 = false

See also

Ways to use isSymbolicEqualOrdinary :