From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Noah Lavine Newsgroups: gmane.lisp.guile.user Subject: Re: Can somebody help to explain why result from atan does not equal a real? Date: Thu, 31 Jan 2013 09:52:44 -0500 Message-ID: References: <20130131145017.GA27085@jocasta.intra> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: multipart/alternative; boundary=bcaec5171f1d8e8f1304d496c744 X-Trace: ger.gmane.org 1359643973 5967 80.91.229.3 (31 Jan 2013 14:52:53 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 31 Jan 2013 14:52:53 +0000 (UTC) Cc: Guile Mailing List To: John Darrington Original-X-From: guile-user-bounces+guile-user=m.gmane.org@gnu.org Thu Jan 31 15:53:13 2013 Return-path: Envelope-to: guile-user@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1U0vVn-0002kf-9L for guile-user@m.gmane.org; Thu, 31 Jan 2013 15:53:11 +0100 Original-Received: from localhost ([::1]:36840 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1U0vVV-0004sF-0b for guile-user@m.gmane.org; Thu, 31 Jan 2013 09:52:53 -0500 Original-Received: from eggs.gnu.org ([208.118.235.92]:45192) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1U0vVP-0004rx-28 for guile-user@gnu.org; Thu, 31 Jan 2013 09:52:48 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1U0vVN-0004tZ-RA for guile-user@gnu.org; Thu, 31 Jan 2013 09:52:46 -0500 Original-Received: from mail-ve0-f177.google.com ([209.85.128.177]:60665) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1U0vVN-0004sx-Ly for guile-user@gnu.org; Thu, 31 Jan 2013 09:52:45 -0500 Original-Received: by mail-ve0-f177.google.com with SMTP id m1so2075368ves.36 for ; Thu, 31 Jan 2013 06:52:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:x-received:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type; bh=geM2BcEbqA5y05t3u2qtbWNfQl03IRQXK7873ebgdgs=; b=P9ZmfAuX0NArv9pC+VJtZ8A48IOLrIy0EadZXQd2QZWC7QqbuRtcv4zsxblKQt8EvT SRGNXpXEYeyNICvrp8Rzx/BBvVW50qEkLAVp1bUd/7QrmlarGi25/jezXqatRyz5vjEe 7nV+Kr9N/sKyii1SMIHzKb2NMgUMGIRZUP7oIRn+iJXTsYvLpeg8eRBNYExub/Zeh59D 38dclgdxexmb8XShN6LOtP+KlzFomBx6qhFJ8Bqi9Kaho46muHxb7vWu8QtQseqeB4P1 nphfIqKDp0VQ6PaAywPlYEh0wjXJZPdS4njOX0ud/xCHUdg5Tf0XwJubSwnh3wUC5fgU yFrA== X-Received: by 10.52.180.202 with SMTP id dq10mr7171367vdc.129.1359643965033; Thu, 31 Jan 2013 06:52:45 -0800 (PST) Original-Received: by 10.58.171.41 with HTTP; Thu, 31 Jan 2013 06:52:44 -0800 (PST) In-Reply-To: <20130131145017.GA27085@jocasta.intra> X-Google-Sender-Auth: _awTaNH82M1GSchC8YOioYgG2YU X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 209.85.128.177 X-BeenThere: guile-user@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: General Guile related discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guile-user-bounces+guile-user=m.gmane.org@gnu.org Original-Sender: guile-user-bounces+guile-user=m.gmane.org@gnu.org Xref: news.gmane.org gmane.lisp.guile.user:9955 Archived-At: --bcaec5171f1d8e8f1304d496c744 Content-Type: text/plain; charset=ISO-8859-1 On Thu, Jan 31, 2013 at 9:50 AM, John Darrington < john@darrington.wattle.id.au> wrote: > > pi is an irrational number. You would need an infinite number of digits > wouldn't you? > Good point :-). All I meant was enough digits that it parsed as the same floating-point number that (atan 0 -1) returns. Noah Lavine --bcaec5171f1d8e8f1304d496c744 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable



On Thu, Jan 31, 2013 at 9:50 AM, John Darrington = <john@= darrington.wattle.id.au> wrote:
pi is an irrational number. =A0You would need an infinite number of digits = wouldn't you?
<= /div>

Good point :-). All I meant was enough digits that it parsed as t= he same floating-point number that (atan 0 -1) returns.

Noah Lavine

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