From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 21774 invoked by alias); 27 May 2005 12:36:10 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 21749 invoked by uid 22791); 27 May 2005 12:36:03 -0000 Received: from vinc17.net4.nerim.net (HELO ay.vinc17.org) (62.212.121.106) by sourceware.org (qpsmtpd/0.30-dev) with ESMTP; Fri, 27 May 2005 12:36:03 +0000 Received: from lefevre by ay.vinc17.org with local (Exim 4.50) id 1Dbe4G-00035z-9S; Fri, 27 May 2005 14:36:00 +0200 Date: Fri, 27 May 2005 13:56:00 -0000 From: Vincent Lefevre To: gcc@gcc.gnu.org Subject: Re: Sine and Cosine Accuracy Message-ID: <20050527123600.GS5967@ay.vinc17.org> Mail-Followup-To: gcc@gcc.gnu.org References: <4295DE66.2050701@coyotegulch.com> <20050526154754.GA10785@redhat.com> <4295F374.6070901@coyotegulch.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <4295F374.6070901@coyotegulch.com> X-Mailer-Info: http://www.vinc17.org/mutt/ User-Agent: Mutt/1.5.9-vl-20050401i X-SW-Source: 2005-05/txt/msg01491.txt.bz2 On 2005-05-26 12:04:04 -0400, Scott Robert Ladd wrote: > I've never quite understood the necessity for performing trig > operations on excessively large values, but perhaps my problem > domain hasn't included such applications. This can happen in some numerical applications (the same expressions are used for small and large values). An accurate value wouldn't necessarily be meaningful, but some properties can be necessary or at least useful, such as: * Mathematical properties, e.g. |sin(x)| <= 1 and sin²x + cos²x = 1. * Properties concerning the distribution of the values of sin(x) for large values of x. * Reproducibility of the results across different platforms (may be useful for debugging purpose, in particular). -- Vincent Lefèvre - Web: 100% accessible validated (X)HTML - Blog: Work: CR INRIA - computer arithmetic / SPACES project at LORIA