Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!rpi!leah!bingvaxu!kym From: kym@bingvaxu.cc.binghamton.edu (R. Kym Horsell) Newsgroups: comp.arch Subject: Re: benchmark for evaluating extended precision (data, long) Keywords: extended precision,multiply,benchmark,arithmetic Message-ID: <3999@bingvaxu.cc.binghamton.edu> Date: 13 Sep 90 15:50:29 GMT References: <3989@bingvaxu.cc.binghamton.edu> <119858@linus.mitre.org> <2114@charon.cwi.nl> <119983@linus.mitre.org> Reply-To: kym@bingvaxu.cc.binghamton.edu.cc.binghamton.edu (R. Kym Horsell) Organization: SUNY Binghamton, NY Lines: 16 In article <119983@linus.mitre.org> bs@linus.mitre.org (Robert D. Silverman) writes: \\\ >This is true when dividing a multi-precise number by a single precision >number. It is not true when dividing two multi-precise numbers. >Dividing 2n bits by n bits is O(n^2) not O(n). \\\ The complexity of _division_ is still (I understand) an open question. According to some (old) work by Cook & Aanderaa it is _unlikely_ to be less than O(n log n/(log log n)^2) on ``conventional'' machines. The best division _algorithm_ that I know of performs O(n log n log log n). -Kym Horsell