From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,4ac6504560f5ef27 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2004-03-05 10:04:37 PST Path: archiver1.google.com!news2.google.com!newsfeed2.dallas1.level3.net!news.level3.com!priapus.visi.com!orange.octanews.net!news.octanews.net!green.octanews.net!news-out.octanews.net!news.glorb.com!wn14feed!worldnet.att.net!207.35.177.252!nf3.bellglobal.com!nf1.bellglobal.com!nf2.bellglobal.com!news20.bellglobal.com.POSTED!not-for-mail From: "Warren W. Gay VE3WWG" User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: Little Endian -> Big Endian (Ada95 / GNAT), Whats with floating point types? References: <4046b474_1@127.0.0.1> <1078425292.143938@master.nyc.kbcfp.com> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Message-ID: Date: Fri, 05 Mar 2004 12:50:21 -0500 NNTP-Posting-Host: 198.96.223.163 X-Complaints-To: abuse@sympatico.ca X-Trace: news20.bellglobal.com 1078508961 198.96.223.163 (Fri, 05 Mar 2004 12:49:21 EST) NNTP-Posting-Date: Fri, 05 Mar 2004 12:49:21 EST Organization: Bell Sympatico Xref: archiver1.google.com comp.lang.ada:6091 Date: 2004-03-05T12:50:21-05:00 List-Id: I am going to reply to my own post here, since after reading and posting, I decided to satisfy my curiosity and ... Warren W. Gay VE3WWG wrote: > Hyman Rosen wrote: > >> Warren W. Gay VE3WWG wrote: >> >>> you can still represent a machine dependant number with >> >> > repeating decimal places >> >> There are no such numbers (on any common hardware). > > Because I am not in a position here and now to > say "here is one", all I can do is say "I _think_ you're > incorrect about this". I seem to recall one or more > machine formats that keep one bit of state that says > this is a repeating digit (perhaps I am thinking of > a FPU register, but I do know that I have seen > it somewhere). Clearly the IEEE format does not include any concept of a repeating bit. I have to wonder where I saw this now, and can only guess that I saw it as part of a FPU state bit or something. >> Whether >> it's IEEE, VAX, or any of a variety of other forms of hardware >> floating point representation, all of them can be written >> exactly as a finite length decimal number (not counting the >> bit patterns which do not represent numbers, of course). > > So lacking any representation sources at the moment, are you > saying that there is absolutely no bit that indicates that > a digit repeats? I am not sure that you are wrong - but I > seem to recall differently. Perhaps, someone can provide > the relevant details. I'll save everyone the trouble (thanks Google - I should have done this first). One source is: http://www.csit.fsu.edu/~burkardt/papers/ieee.html There is clearly no allowance for any "repeating bit". ... >> The algorithms were both published in Proceedings of the ACM SIGPLAN >> '90 Conference on Programming Language Design and Implementation. >> >> G. L. Steele Jr. and J. L. White. >> How to Print Floating Point Numbers Accurately. >> >> W. D. Clinger >> How to Read Floating Point Numbers Accurately >> >> You can find free implementations of these algorithms in C at >> . > > Can you point me/us to an online IEEE format description? I'd > like to check my memory for parity errors ;-) No need now. -- Warren W. Gay VE3WWG http://ve3wwg.tk