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*To*: srfi-77@xxxxxxxxxxxxxxxxx*Subject*: Re: arithmetic issues*From*: Marcin 'Qrczak' Kowalczyk <qrczak@xxxxxxxxxx>*Date*: Sat, 22 Oct 2005 02:45:18 +0200*Delivered-to*: srfi-77@xxxxxxxxxxxxxxxxx*In-reply-to*: <4359872B.8070401@xxxxxxxxxxxxxxxx> (Alan Watson's message of "Fri, 21 Oct 2005 19:26:19 -0500")*Mail-followup-to*: srfi-77@xxxxxxxxxxxxxxxxx*References*: <20051021145326.816C11B77BB@xxxxxxxxxxxxxxxxxxxxx> <4359872B.8070401@xxxxxxxxxxxxxxxx>*Sender*: Marcin 'Qrczak' Kowalczyk <qrczak@xxxxxxxxxx>*User-agent*: Gnus/5.1006 (Gnus v5.10.6) Emacs/21.3 (gnu/linux)

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 identifier. >> 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/

**References**:**arithmetic issues***From:*Aubrey Jaffer

**Re: arithmetic issues***From:*Alan Watson

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