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Divisor :: isDivAmbient

isDivAmbient -- Checks whether the ambient ring of a given divisor is the given ring

Synopsis

Description

Returns true if the ambient ring of D1 is equal to (===) R1. Otherwise it returns false.

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

o1 = R

o1 : QuotientRing
i2 : D = divisor({-1, 2}, {ideal(x, z), ideal(y, z)})

o2 = -1*Div(x, z) + 2*Div(y, z) of R

o2 : WDiv
i3 : isDivAmbient(D, R)

o3 = true
i4 : S = QQ[a,b]

o4 = S

o4 : PolynomialRing
i5 : isDivAmbient(D, S)

o5 = false

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

Ways to use isDivAmbient :