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Divisor :: dualize

dualize -- finds an ideal or module isomorphic to Hom(M, R)

Synopsis

Description

Find the module/ideal isomorphic to the dual of the module/ideal, in other words it computes HomR(M, R).

i1 : R = QQ[x,y,z]/ideal(x^2-y*z);
i2 : m = ideal(x,y,z);

o2 : Ideal of R
i3 : dualize(m)

o3 = ideal x

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

o4 : Ideal of R
i5 : dualize(I)

o5 = ideal (z, x)

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

o6 = ideal z

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

             2
o7 = ideal (z , x*z)

o7 : Ideal of R

See also

Ways to use dualize :