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coefficient(BasicList,BasicDivisor) -- get the coefficient of an ideal for a fixed divisor

Function: coefficient
Usage:

coefficient(L, D)
Inputs:
- L, a basic list, the list of elements in a Grobner basis of a height one prime ideal that we want to find the coefficient of
- D, an instance of the type BasicDivisor, the divisor in question
Outputs:
- a number,

Description

This function returns the coefficient of $D$ along the prime divisor generated by $L$ assuming $L$ is the ordered list of an element

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

i2 : E = divisor(x*u)

o2 = Div(v, x) + Div(u, y) + 2*Div(u, x)

o2 : WeilDivisor on R

i3 : coefficient({u, x}, E)

o3 = 2

i4 : coefficient({x, u}, E)

o4 = 0

See also

coefficient(Ideal,BasicDivisor) -- get the coefficient of an ideal for a fixed divisor
coefficients(BasicDivisor) -- get the list of coefficients of a divisor

Ways to use this method:

coefficient(BasicList,BasicDivisor) -- get the coefficient of an ideal for a fixed divisor

The source of this document is in Divisor.m2:2457:0.