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 X-Google-Thread: 103376,69bb03cc695b330a X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2001-03-10 08:50:12 PST Path: supernews.google.com!sn-xit-03!supernews.com!freenix!teaser.fr!fr.clara.net!heighliner.fr.clara.net!news.tele.dk!128.39.3.166!uninett.no!nntp.uib.no!georg From: georg@ii.uib.no (Hans Georg Schaathun) Newsgroups: comp.lang.ada Subject: Re: Large numbers (or is Ada the choice for me?) Date: 10 Mar 2001 16:49:41 GMT Organization: University of Bergen Message-ID: References: <98bbbg$jmf$1@nh.pace.co.uk> <98bp0c$nsq$1@nh.pace.co.uk> NNTP-Posting-Host: admiral.ii.uib.no Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-Trace: toralf.uib.no 984242981 8325 129.177.19.2 (10 Mar 2001 16:49:41 GMT) X-Complaints-To: abuse@uib.no NNTP-Posting-Date: 10 Mar 2001 16:49:41 GMT User-Agent: slrn/0.9.5.6 [hacked] (UNIX) Xref: supernews.google.com comp.lang.ada:5609 Date: 2001-03-10T16:49:41+00:00 List-Id: On Fri, 9 Mar 2001 18:28:43 -0500, Marin David Condic wrote: : Well, let me check a few assumptions. 1) We can never run out of numbers. : (Go ahead. Use all you want. We'll make more! :-) 2) We *can* and *will* : eventually run out of memory. Hence, even if you did all the math with some : sort of fractional representation rather than a decimal representation, it : would be possible to construct numbers that exceed the capacity of the : machine. That is just as simple and likely as creating a problem it takes 50 years to solve (with infinite memory resources). The solution is rather simple, the program returns error, `sorry, sam, your problem is to large'. I am certainly aware that I won't be able to solve all the problems I might want to create, but test runs in maple indicates that _this_ problem is solvable if memory is handled with care. : Hence, I think it stands to reason that you would be off on a : fool's errand to insist on no approximations or limitations whatsoever. I don't insist on no limitations. I accept the limitations of memory and CPU resources, but I want to do as much as possible within these limits. My problem is primarily to determine whether the system has integer solutions or not, which means that I can't accept (not even risk) any rounding errors of � or more. I doubt that floating point can save significant amounts of memory with this requirement. : There has to be some sort of practical upper limit imposed by the available : memory if nothing else. Yes, so I won't cry over problems which can't be solved. : As I said elsewhere, I rather hastily picked a bad example - but I think the : point still stands that one will have to live with some sort of : approximation on the representation - even if in practice, it may be so : small as to not matter. Wrong, my outset is to solve a couple of practical problems, not to solve any problem you might think of. :-- Hans Georg -- Signature en panne.