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 |