From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 31961 invoked by alias); 26 May 2005 19:28:41 -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 31928 invoked by uid 22791); 26 May 2005 19:28:32 -0000 Received: from smtp-104-thursday.nerim.net (HELO kraid.nerim.net) (62.4.16.104) by sourceware.org (qpsmtpd/0.30-dev) with ESMTP; Thu, 26 May 2005 19:28:32 +0000 Received: from uniton.integrable-solutions.net (gdr.net1.nerim.net [62.212.99.186]) by kraid.nerim.net (Postfix) with ESMTP id 111A040E2D; Thu, 26 May 2005 21:28:29 +0200 (CEST) Received: from uniton.integrable-solutions.net (localhost [127.0.0.1]) by uniton.integrable-solutions.net (8.12.10/8.12.10/SuSE Linux 0.7) with ESMTP id j4QKd0KY004372; Thu, 26 May 2005 22:39:00 +0200 Received: (from gdr@localhost) by uniton.integrable-solutions.net (8.12.10/8.12.10/Submit) id j4QKd0Mv004371; Thu, 26 May 2005 22:39:00 +0200 To: Scott Robert Ladd Cc: Richard Henderson , gcc@gcc.gnu.org Subject: Re: Sine and Cosine Accuracy References: <4295DE66.2050701@coyotegulch.com> <20050526154754.GA10785@redhat.com> <4295F374.6070901@coyotegulch.com> From: Gabriel Dos Reis In-Reply-To: <4295F374.6070901@coyotegulch.com> Date: Thu, 26 May 2005 21:15:00 -0000 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-SW-Source: 2005-05/txt/msg01453.txt.bz2 Scott Robert Ladd writes: | Richard Henderson wrote: | > On Thu, May 26, 2005 at 10:34:14AM -0400, Scott Robert Ladd wrote: | > | >> static const double range = PI; // * 2.0; | >> static const double incr = PI / 100.0; | > | > | > The trig insns fail with large numbers; an argument | > reduction loop is required with their use. | | Yes, but within the defined mathematical ranges for sine and cosine -- | [0, 2 * PI) -- this is what they call "post-modern maths"? [...] | 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. The world is flat; I never quite understood the necessity of spherical trigonometry. -- Gaby