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Divisor :: reflexifyIdeal

reflexifyIdeal -- Calculate the double dual of an ideal

Synopsis

Description

Get the double dual (S2 - identification) of an ideal. If KnownNormal is false (default value is true), then the function will check whether it is normal, if not it will compute using a slower method which will give the correct 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 : reflexifyIdeal(m)

o3 = ideal 1

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

o4 = ideal (x, y)

o4 : Ideal of R
i5 : reflexifyIdeal(I)

o5 = ideal (y, x)

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

o6 = ideal y

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

             2
o7 = ideal (y , x*y)

o7 : Ideal of R

See also

Ways to use reflexifyIdeal :