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Divisor :: sameDivAmbient

sameDivAmbient -- Checks whether the ambient ring of the given divisors are equal

Synopsis

Description

Returns true if the ambient ring of D1 is equal (===) to the ambient ring of D2. Otherwise it returns false.

i1 : R1 = QQ[x, y, z] / ideal(x * y - z^2)

o1 = R1

o1 : QuotientRing
i2 : R2 = QQ[a, b, c, d] / ideal(a * b - c * d)

o2 = R2

o2 : QuotientRing
i3 : D1 = divisor({1, -2}, {ideal(x, z), ideal(y, z)})

o3 = 1*Div(x, z) + -2*Div(y, z) of R1

o3 : WDiv
i4 : D2 = divisor({-3, 4}, {ideal(a, c), ideal(b, d)})

o4 = -3*Div(a, c) + 4*Div(b, d) of R2

o4 : WDiv
i5 : sameDivAmbient(D1, 2*D1)

o5 = true
i6 : sameDivAmbient(D1, D2)

o6 = false

If either D1 or D2 is the zero divisor, it always returns true.

Ways to use sameDivAmbient :