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Divisor :: coeff

coeff -- Get the coefficient of a given ideal for a fixed divisor

Synopsis

Description

Returns the coefficient of D along the prime divisor associated to P (or generated by L). Frequently n or m are integers, rational or real numbers if D is WDiv, QDiv or RDiv respectively

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

o1 = R

o1 : QuotientRing
i2 : D = divisor(x)

o2 = 1*Div(v, x) + 1*Div(u, x) of R

o2 : WDiv
i3 : coeff(ideal(x,u), D)

o3 = 1
i4 : E = divisor(x*u)

o4 = 1*Div(u, y) + 1*Div(v, x) + 2*Div(u, x) of R

o4 : WDiv
i5 : coeff(ideal(x,u), E)

o5 = 2

Ways to use coeff :