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Divisor :: divMinus

divMinus -- Get the negative part of a divisor

Synopsis

Description

Return the negative part of a given divisor

i1 : R = QQ[x, y, u, v] / ideal(x * y - u * v)

o1 = R

o1 : QuotientRing
i2 : D = divisor({1, -3, 5, -7}, {ideal(x, u), ideal(x, v), ideal(y, u), ideal(y, v)})

o2 = 5*Div(y, u) + -7*Div(y, v) + 1*Div(x, u) + -3*Div(x, v) of R

o2 : WDiv
i3 : divMinus( D )

o3 = 3*Div(x, v) + 7*Div(y, v) of R

o3 : WDiv

See also

Ways to use divMinus :