Path: csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!aioe.org!news.stack.nl!newsfeed.xs4all.nl!newsfeed5.news.xs4all.nl!xs4all!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.028 X-Spam-Evidence: '*H*': 0.94; '*S*': 0.00; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:80.91.229.12': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'received:lo.gmane.org': 0.09; 'wrote:': 0.14; 'header:In-Reply- To:1': 0.22; 'url:wiki': 0.24; "i'm": 0.26; 'hi,': 0.29; 'that...': 0.31; 'zero.': 0.31; "can't": 0.31; 'to:addr:python- list': 0.32; 'using': 0.34; 'header:X-Complaints-To:1': 0.34; 'url:en': 0.35; 'header:User-Agent:1': 0.35; 'issue': 0.37; 'code:': 0.38; 'url:org': 0.38; 'received:org': 0.38; 'though,': 0.39; 'to:addr:python.org': 0.39; 'header:Mime-Version:1': 0.39; 'header:Received:5': 0.40; 'might': 0.40; 'received:86': 0.60; 'further': 0.62; 'numbers:': 0.91 X-Injected-Via-Gmane: http://gmane.org/ To: python-list@python.org From: Dan Goodman Subject: Re: Terrible FPU performance Date: Tue, 26 Apr 2011 21:14:43 +0200 References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Gmane-NNTP-Posting-Host: 57.44.69-86.rev.gaoland.net User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.9.2.15) Gecko/20110303 Lightning/1.0b2 Thunderbird/3.1.9 In-Reply-To: X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 15 NNTP-Posting-Host: 82.94.164.166 X-Trace: 1303845302 news.xs4all.nl 41113 [::ffff:82.94.164.166]:52518 X-Complaints-To: abuse@xs4all.nl Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:4068 Hi, On 26/04/2011 15:40, Mihai Badoiu wrote: > I have terrible performance for multiplication when one number gets very > close to zero. I'm using cython by writing the following code: This might be an issue with denormal numbers: http://en.wikipedia.org/wiki/Denormal_number I don't know much about them though, so I can't advise any further than that... Dan