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=-0.3 required=5.0 tests=BAYES_00,FREEMAIL_FROM, REPLYTO_WITHOUT_TO_CC autolearn=no autolearn_force=no version=3.4.4 X-Google-Thread: a07f3367d7,3cff83f35107b37b X-Google-Attributes: gida07f3367d7,public,usenet X-Google-NewGroupId: yes X-Google-Language: ENGLISH,ASCII-7-bit Received: by 10.180.84.234 with SMTP id c10mr41317wiz.4.1349942585730; Thu, 11 Oct 2012 01:03:05 -0700 (PDT) MIME-Version: 1.0 Path: q11ni134269349wiw.1!nntp.google.com!feeder1.cambriumusenet.nl!feeder3.cambriumusenet.nl!feed.tweaknews.nl!193.141.40.65.MISMATCH!npeer.de.kpn-eurorings.net!npeer-ng0.de.kpn-eurorings.net!border2.nntp.ams2.giganews.com!border4.nntp.ams.giganews.com!border2.nntp.ams.giganews.com!backlog2.nntp.dca.giganews.com!border4.nntp.dca.giganews.com!border2.nntp.dca.giganews.com!nntp.giganews.com!news.glorb.com!aioe.org!.POSTED!not-for-mail From: anon@att.net Newsgroups: comp.lang.ada Subject: Re: Multiplying fixed-point by long integer Date: Fri, 5 Oct 2012 05:14:08 +0000 (UTC) Organization: Aioe.org NNTP Server Message-ID: References: Reply-To: anon@anon.org NNTP-Posting-Host: iHNplaHfkTcix/EBN43YWw.user.speranza.aioe.org X-Complaints-To: abuse@aioe.org X-Notice: Filtered by postfilter v. 0.8.2 X-Newsreader: IBM NewsReader/2 2.0 X-Original-Bytes: 2214 Date: 2012-10-05T05:14:08+00:00 List-Id: An old discussion mostly bwtween the 1980s and 90s. A file "farith.c" /* * multi-precision multiplication, division and exponentiation * for fixed point computations. */ ... which is a componet of "Ada/Ed" package that uses the "Multiple Precision Integer Arithetic Package" written by Robert B. K. Dewar in June 16, 1980. To preform some of the arithmetic calculations used in the "Ada/Ed" system. Do a Google search for url of a ftp link to file using keywords multi-precision arithmetic "Robert B. K. Dewar" Ada/Ed farith.c Other discussion on this subject can be found by just google and added the name Robert B. K. Dewar. Most will be between 1980 and 1999. In , Adam Beneschan writes: >I don't think I've ever seen this problem discussed before ... > >4.5.5 defines predefined multiplication operators between any fixed-point t= >ype and Integer. However, it isn't defined for any other integer type. Th= >is can cause a problem if I have an integer type whose bounds are larger th= >an Integer, since it obviously won't work to convert it to Integer. Has an= >yone encountered this problem before, and how did you solve it? I'm hesita= >nt to try to solve it by converting things to floating point, since the man= >tissa of a floating-point may have fewer bits than the fixed-point or integ= >er type, and fixed-point multiplication by an integer should be exact. > > -- thanks, Adam