From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Jay Belanger Newsgroups: gmane.emacs.devel Subject: Re: A question on the range of floats in Emacs Date: Tue, 17 Jul 2007 15:41:12 -0500 Message-ID: <878x9e4vbr.fsf@gmail.com> References: <87sl7nzt23.fsf@gmail.com> Reply-To: jay.p.belanger@gmail.com NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable X-Trace: sea.gmane.org 1184704883 1064 80.91.229.12 (17 Jul 2007 20:41:23 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Tue, 17 Jul 2007 20:41:23 +0000 (UTC) Cc: jay.p.belanger@gmail.com To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Jul 17 22:41:22 2007 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1IAtrG-0005MQ-2p for ged-emacs-devel@m.gmane.org; Tue, 17 Jul 2007 22:41:22 +0200 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1IAtrF-0007Pb-Ma for ged-emacs-devel@m.gmane.org; Tue, 17 Jul 2007 16:41:21 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1IAtrC-0007Ot-9y for emacs-devel@gnu.org; Tue, 17 Jul 2007 16:41:18 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1IAtrA-0007OE-Ou for emacs-devel@gnu.org; Tue, 17 Jul 2007 16:41:17 -0400 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1IAtrA-0007O9-Kf for emacs-devel@gnu.org; Tue, 17 Jul 2007 16:41:16 -0400 Original-Received: from uranium.truman.edu ([150.243.160.94]) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1IAtrA-0007Pb-0P for emacs-devel@gnu.org; Tue, 17 Jul 2007 16:41:16 -0400 Original-Received: from uranium.truman.edu (localhost.localdomain [127.0.0.1]) by localhost (Postfix) with SMTP id E7BC157B58; Tue, 17 Jul 2007 15:41:14 -0500 (CDT) Original-Received: from localhost.localdomain (vh215402.truman.edu [150.243.64.20]) by uranium.truman.edu (Postfix) with ESMTP id C7F0260154; Tue, 17 Jul 2007 15:41:13 -0500 (CDT) In-Reply-To: ("Johan =?iso-8859-1?Q?Bockg=E5rd=22's?= message of "Tue\, 17 Jul 2007 16\:49\:47 +0200") User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.1.50 (gnu/linux) X-detected-kernel: Linux 2.6, seldom 2.4 (older, 4) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:75024 Archived-At: bojohan+news@dd.chalmers.se (Johan Bockg=E5rd) writes: ... > The cl package can determine a number of floating point parameters. > See > > (info "(cl)Implementation Parameters") Wonderful; thanks. I guess this information isn't easily accessible, so it is=20 computed. I played around with the largest and smallest floats, and I was wondering about precision. Near the smallest float, the precision can be small; on my computer, 5e-324, 5.1e-324 and 4.9e-324 all evaluate to 5e-324; 3.47e-323 evaluates to 3.5e-324, etc. Is there a range (say from smallest-exponent + N to largest-exponent - N) in which the precision is fixed? (It appears that way here; is it true in general?) Jay