Path: csiph.com!usenet.pasdenom.info!news.albasani.net!newsfeed.freenet.ag!news2.euro.net!newsgate.cistron.nl!newsgate.news.xs4all.nl!194.109.133.85.MISMATCH!newsfeed.xs4all.nl!newsfeed6.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 0.021 X-Spam-Evidence: '*H*': 0.96; '*S*': 0.00; 'missed': 0.09; '*is*': 0.09; 'closest': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; '...]': 0.16; 'finney': 0.16; 'message- id:@dough.gmane.org': 0.16; 'received:80.91.229.3': 0.16; 'received:plane.gmane.org': 0.16; 'value:': 0.16; 'wed,': 0.16; 'wrote:': 0.17; '>>>': 0.18; 'are:': 0.20; 'not,': 0.21; '15,': 0.23; 'second': 0.24; 'header:In-Reply-To:1': 0.25; 'header:User- Agent:1': 0.26; 'header:X-Complaints-To:1': 0.28; 'adequate': 0.29; "d'aprano": 0.29; 'steven': 0.29; 'writes:': 0.29; 'from:addr:yahoo.co.uk': 0.32; 'to:addr:python-list': 0.33; 'another': 0.33; 'that,': 0.34; 'ben': 0.35; 'received:org': 0.36; 'anything': 0.36; 'skip:4 10': 0.37; 'far': 0.37; 'subject:: ': 0.38; 'mark': 0.38; 'to:addr:python.org': 0.39; 'header:Received:5': 0.40; 'here:': 0.62; 'wide': 0.62; 'more': 0.63; '8bit%:40': 0.65; 'jul': 0.65; 'civil': 0.66; 'continued': 0.66; 'skip:\xe2 10': 0.66; 'believe': 0.69; 'subjectcharset:utf-8': 0.72; 'misses': 0.84; 'received:89': 0.86; 'maarten': 0.91 X-Injected-Via-Gmane: http://gmane.org/ To: python-list@python.org From: Mark Lawrence Subject: Re: the meaning of =?UTF-8?B?csOvwr7igKIuLi4uLi4uw6/Cvg==?= Date: Wed, 25 Jul 2012 07:37:33 +0100 References: <500d0632$0$1504$c3e8da3$76491128@news.astraweb.com> <87r4s1rzv2.fsf@benfinney.id.au> <45c8f299-3420-4836-afcb-6e07957ba344@googlegroups.com> <87lii8sfmw.fsf@benfinney.id.au> <500f8d0c$0$11120$c3e8da3@news.astraweb.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Gmane-NNTP-Posting-Host: host-89-243-205-160.as13285.net User-Agent: Mozilla/5.0 (Windows NT 6.0; rv:14.0) Gecko/20120713 Thunderbird/14.0 In-Reply-To: <500f8d0c$0$11120$c3e8da3@news.astraweb.com> X-Antivirus: avast! (VPS 120724-1, 24/07/2012), Outbound message X-Antivirus-Status: Clean 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: 52 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1343198175 news.xs4all.nl 6954 [2001:888:2000:d::a6]:32809 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:26024 On 25/07/2012 07:07, Steven D'Aprano wrote: > On Wed, 25 Jul 2012 13:07:03 +1000, Ben Finney wrote: > >> Maarten writes: >> >>> You just missed it: >>> 22/7 >> >> Which is appropriate, since 22/7 misses π by a wide margin. (355/113 is >> my favourite approximation to π, and is far more accurate.) > > Approximation? Pffft. I use the exact value: > > π = 16*arctan(1/5) - 4*arctan(1/239) > > > For those lacking ambition, another approximation is: > > π ≈ 9801 ÷ (2206*√2) > > Other interesting approximations are: > > π ≈ 9/5 + √(9/5) > > π ≈ √√(2143/22) > > See more here: > > http://mathworld.wolfram.com/PiFormulas.html > http://mathworld.wolfram.com/PiApproximations.html > > >> −1 on associating 22/7 as anything to do with π. > > I believe that 22/7 is the closest approximation to π with a denominator > under 100. It is the second convergent of the continued fraction: > > π = [3; 7, 15, 1, 292, 1, 1, 1, 2, 1, 3, 1, 14, 2, 1, 1, 2, 2, 2, 2, ...] > > which means that, like it or not, 22/7 *is* associated with π. > > > Any civil engineers reading this who would find 22/7 perfectly adequate for their task? -- Cheers. Mark Lawrence.