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

i2 : D = divisor(x)
o2 = Div(v, x) + Div(u, x)
o2 : WeilDivisor on R

i3 : coefficient(ideal(x,u), D)
o3 = 1

i4 : E = divisor(x*u)
o4 = Div(v, x) + Div(u, y) + 2*Div(u, x)
o4 : WeilDivisor on R

i5 : coefficient(ideal(x,u), E)
o5 = 2
