Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!sun-barr!newstop!east!tjp!jpainter From: jpainter@tjp.East.Sun.COM (John Painter - Sun BOS Hardware) Newsgroups: comp.arch Subject: Re: hardware complex arithmetic support Message-ID: <725@east.East.Sun.COM> Date: 18 Aug 89 17:06:15 GMT References: <1672@crdgw1.crd.ge.com> <4781@freja.diku.dk> Sender: news@east.East.Sun.COM Reply-To: jpainter@tjp.East.Sun.COM (John Painter - Sun BOS Hardware) Organization: Sun Microsystems, Billerica MA Lines: 45 In article <4781@freja.diku.dk> njk@freja.diku.dk (Niels J|rgen Kruse) writes: >davidsen@sungod.crd.ge.com (ody) writes: > >> Why hasn't anyone built a complex FPU? This seems like a reasonable >>thing to do, in term of being common. It could probably be built into >>one of the existing micro FPUs without too much trouble (obviously needs >>more microcode), but I doubt that you win much because the chip doesn't >>have the power to do a lot in parallel. > >As far as i can tell, the main advantage of hardware support >for complex arithmetic is the greater encoding density allowed >by a dedicated storage format for complex numbers. > >Consider that it is meaningless from a numerical viewpoint to >represent one component of a complex number with greater >accuracy than the other. > Meaningless in what applications? I might want to know phase relation- ships with more precision offered when the phase of the voltage and current components are nearly 90 degrees out of phase. /Tjp -disclaimer disclaimer II SSeeee eevveerryytthhiinngg ttwwiiccee.. - (Catch it 22 times at a store near you) The following lines are no satisfy Mr. Mailer now You peeked! Bad ... Bad news reader Baa....dddd!