Path: g2news2.google.com!news1.google.com!news.glorb.com!news2.glorb.com!news-in-01.newsfeed.easynews.com!news-in-02.newsfeed.easynews.com!core-easynews!easynews.com!easynews!en-nntp-09.dc1.easynews.com.POSTED!ron-shepard From: Ron Shepard Newsgroups: comp.lang.fortran Subject: Re: how to declare doubles in f95 Organization: little, if any References: <0b898c8f-5866-4942-bf2b-171655d6658a@r15g2000prh.googlegroups.com> <1iu9kv0.1bz1pn5whvfi8N%nospam@see.signature> <1nw9yyz9qhd9p.1hjp1zbzhjv22$.dlg@40tude.net> <1iu9ut8.eu0q92m2gmncN%nospam@see.signature> <211848d9p01u$.s5az6kged1ru$.dlg@40tude.net> <1iua0ko.lz5o02c9847kN%nospam@see.signature> User-Agent: MT-NewsWatcher/3.5.3b3 (Intel Mac OS X) Message-ID: Lines: 17 X-Complaints-To: abuse@easynews.com X-Complaints-Info: Please be sure to forward a copy of ALL headers otherwise we will be unable to process your complaint properly. Date: Thu, 29 Jan 2009 09:22:48 -0600 In article <1iua0ko.lz5o02c9847kN%nos...@see.signature>, nos...@see.signature (Richard Maine) wrote: > For > today's systems, that's a more realistic scenario - that you might > specify double precision expecting to get 64 bits and find that instead > it gets you 128. Not just today's systems, this is the way many computers have worked in the past, 64-bit words for single precision, and 128-bit words for double precision. The same is true for 60 and 120 bit word machines, which have been common in the past. And if the 128-bit arithmetic is software emulated, then there is a huge, 10x to 20x, penalty for using that arithmetic if single precision is all you really wanted in the first place. $.02 -Ron Shepard