[Date Index] [Thread Index] [Author Index]
Re: Help! Mathematica on my 500MHz outperforms my GHz machine!
In article <870ujq$8kb at smc.vnet.net>, terryis at my-deja.com writes: > Of the more notable responses, RogerWilson (roger.wilson at nomura.co.uk) > wrote to say that Mathematica 3 does all floating point calculations > in software and that the supposedly very fast floating point unit in > my Athlon was therefore not being used (as far as he knew). > > Is this true? I mean no disrespect to Roger but I had always thought > that Mathematica uses both arbitrary and machine precision depending on > the characteristics of the number in question. As long as your inputs specify machine precision numbers, Mathematica typically uses machine precision arithmetic to achieve its results. It will make use of the floating point capabilities of your CPU. This is noted in Section 3.1.6 of _The Mathematica Book_ Fourth Edition. http://documents.wolfram.com/v4/MainBook/3_01/S3.1.6.html Note, however, that this does not include CPU-class-specific optimizations such as Intel's MMX instructions or AMD's 3DNow! instructions. http://support.wolfram.com/Systems/Windows/Compatibility/MMX.html -- P.J. Hinton Mathematica Programming Group paulh at wolfram.com Wolfram Research, Inc. Disclaimer: Opinions expressed herein are those of the author alone.