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Re: arithmetic issues

This page is part of the web mail archives of SRFI 77 from before July 7th, 2015. The new archives for SRFI 77 contain all messages, not just those from before July 7th, 2015.

Alan Watson <a.watson@xxxxxxxxxxxxxxxx> writes:

> Or quotient-and-remainder. Isn't "+" sufficiently overloaded as it is
> without having it stand for "and" :-)

quotient&remainder? Unfortunately quotient,remainder is not a valid

>> Mathematically, mixed exactness complex numbers makes no sense.
>> Twisting the whole numeric tower around this artifice is wrong.
> Maybe, but a cheap way to get an inexact imaginary is an number with
> an exact zero for its real part and an inexact real for its imaginary
> part.

If I understood what William Kahan tried to say in one of his
articles, it is that it's sometimes essential to distinguish between
the real part being 0, 0.0, and -0.0, where having only 0.0 and -0.0
is insufficient. He called the first variant "imaginary type", as in
C99, and claimed that Java made a mistake by providing only a complex
type with two floating point parts.

I might be wrong however because I did not understand the technical
reasoning behind that. I think it had something to do with choosing
the right sides near branch cuts, or maybe with 0 not flipping to the
other side on negation, in contrast to 0.0 and -0.0.

   __("<         Marcin Kowalczyk
   \__/       qrczak@xxxxxxxxxx
    ^^     http://qrnik.knm.org.pl/~qrczak/