isWeilDivisor -- whether a rational/real divisor is in actuality a Weil divisor

Synopsis

• Usage:

  isWeilDivisor( D2 )

• Inputs:
  • D2, an instance of the type RWeilDivisor,
• Outputs:
  • a Boolean value,

Description

i1 : R = QQ[x, y, z];

i2 : D1 = divisor({1/1, 2/2, -6/3}, {ideal(x), ideal(y), ideal(z)}, CoefficientType=>QQ)

o2 = Div(y) + -2*Div(z) + Div(x)

o2 : QWeilDivisor on R

i3 : D2 = divisor({1/2, 3/4, 5/6}, {ideal(y), ideal(z), ideal(x)}, CoefficientType=>QQ)

o3 = 1/2*Div(y) + 3/4*Div(z) + 5/6*Div(x)

o3 : QWeilDivisor on R

i4 : isWeilDivisor( D1 )

o4 = true

i5 : isWeilDivisor( D2 )

o5 = false

See also

• toWeilDivisor -- create a Weil divisor from a Q or R-divisor