coefficients(BasicDivisor) -- get the list of coefficients of a divisor

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

i2 : D = divisor(x);

o2 : WeilDivisor on R

i3 : coefficients(D)

o3 = {1, 1}

o3 : List

i4 : E = divisor(x*u);

o4 : WeilDivisor on R

i5 : coefficients(E)

o5 = {2, 1, 1}

o5 : List

i6 : F = divisor({0, 1/2, -2/3}, {ideal(y, u), ideal(x,u), ideal(x,v)}, CoeffType => QQ)

o6 = -2/3*Div(x, v) + 1/2*Div(x, u) + 0*Div(y, u)

o6 : QWeilDivisor on R

i7 : coefficients(F)

        2  1
o7 = {- -, -, 0}
        3  2

o7 : List

i8 : G = divisor({0.5, -0.667}, {ideal(x,u), ideal(x,v)}, CoeffType => RR)

o8 = -.667*Div(x, v) + .5*Div(x, u)

o8 : RWeilDivisor on R

i9 : coefficients(G)

o9 = {-.667, .5}

o9 : List