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Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0
Alex Shinn <alexshinn@x> writes:
> On Thu, Dec 20, 2012 at 7:19 AM, John Cowan <cowan@x>
> Mark H Weaver scripsit:
> > My point is that your ComplexRepresentation page states that
> Guile and
> > Racket do not support complex numbers of mixed exactness, but
> that's not
> > quite true. There is one important special case of mixed
> exactness that
> > *is* supported in Guile, Racket, Ikarus, and perhaps others.
> In that case, *every* Scheme that supports inexact reals at all, a
> supports complex numbers of mixed exactness such that the
> imag-part is 0.
> I love this reasoning. So every Scheme supports mixed exactness
> quaternions. What a progressive language.
No, several implementations (e.g. SCM, Gauche, Guile before 2.0, and
probably others) do not even support mixed exactness complex numbers of
this special kind, so (imag-part 2.0) => 0.0. If these implementations
supported quaternions, the natural extrapolation of this policy would be
to return 0.0 for all three imaginary components of an inexact real
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