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Divisor :: dualize(..., KnownDomain => ...)

dualize(..., KnownDomain => ...) -- assume R is a domain when computing Hom(M, R)

Synopsis

Description

KnownDomain is an option for IdealStrategy. If it is false (default is true), then the computer will first check whether the ring is a domain, if it is not then it will revert to ModuleStrategy. If KnownDomain is set to true for a non-domain, then the function can return an incorrect answer.

i1 : R = QQ[x,y]/ideal(x*y);
i2 : J = ideal(x,y);

o2 : Ideal of R
i3 : dualize(J, KnownDomain=>true)

o3 = ideal x

o3 : Ideal of R
i4 : dualize(J, KnownDomain=>false)

o4 = ideal (y, x)

o4 : Ideal of R

Further information

See also