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Divisor :: idealToDivisor

idealToDivisor -- Calculate the divisor D so that O_X(D) = I

Synopsis

Description

Finds a divisor D such that O(D) is equal to the reflexification of I. Note such a D will always be anti-effective.
i1 : R = ZZ/7[x,y,z]/ideal(x^3+y^3+z^3)

o1 = R

o1 : QuotientRing
i2 : idealToDivisor( ideal(x) )

o2 = -1*Div(y+2*z, x) + -1*Div(y-3*z, x) + -1*Div(y+z, x) of R

o2 : WDiv
i3 : idealToDivisor( ideal(x, y+z) )

o3 = -1*Div(y+z, x) of R

o3 : WDiv

See also

Ways to use idealToDivisor :