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Divisor :: - BasicDiv

- BasicDiv -- Negation of a divisor

Synopsis

Description

Given a divisor, we return a divisor whose coefficients are the negative of the given one
i1 : R = QQ[x, y, z] / ideal(x * y - z^2 )

o1 = R

o1 : QuotientRing
i2 : D1 = divisor({1, 2}, {ideal(x, z), ideal(y, z)})

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

o2 : WDiv
i3 : -D1

o3 = -1*Div(x, z) + -2*Div(y, z) of R

o3 : WDiv