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Divisor :: dualizeIdeal

dualizeIdeal -- Finds an ideal isomorphic to Hom(I, R)

Synopsis

Description

Returns an ideal isomorphic to Hom(I, R). If KnownNormal is false (default is true), then the computer will first check whether the ambient ring is normal, if it is not then it will perform a (possibly) slower check that will definitely give the right answer.

i1 : R = QQ[x,y,z]/ideal(x^2-y*z)

o1 = R

o1 : QuotientRing
i2 : m = ideal(x,y,z)

o2 = ideal (x, y, z)

o2 : Ideal of R
i3 : dualizeIdeal(m)

o3 = ideal x

o3 : Ideal of R
i4 : I = ideal(x,y)

o4 = ideal (x, y)

o4 : Ideal of R
i5 : dualizeIdeal(I)

o5 = ideal (z, x)

o5 : Ideal of R
i6 : dualizeIdeal(I^2)

o6 = ideal z

o6 : Ideal of R
i7 : dualizeIdeal(I^3)

             2
o7 = ideal (z , x*z)

o7 : Ideal of R

See also

Ways to use dualizeIdeal :