Return-Path: Received: by vger.rutgers.edu via listexpand id ; Thu, 23 Dec 1999 20:06:59 -0500 Received: by vger.rutgers.edu id ; Thu, 23 Dec 1999 20:06:39 -0500 Received: from penguin.prod.itd.earthlink.net ([207.217.120.134]:38090 "EHLO penguin.prod.itd.earthlink.net") by vger.rutgers.edu with ESMTP id ; Thu, 23 Dec 1999 20:06:22 -0500 From: Arthur Jerijian To: linux-kernel@vger.rutgers.edu Subject: Linux Kernel Floating Point Emulation and CORDIC Date: Thu, 23 Dec 1999 15:58:22 -0800 X-Mailer: KMail [version 1.0.28] Content-Type: text/plain; charset=US-ASCII MIME-Version: 1.0 Message-Id: <99122316092902.01246@cel2> Content-Transfer-Encoding: 7BIT Sender: owner-linux-kernel@vger.rutgers.edu Content-Length: 873 Lines: 19 For the mathematics and theoretical computer science enthusiasts here on this list: I have taken a look at the source code of the Linux Kernel floating point emulation engine for i386 (as of 2.2.12, don't know if it changed in 2.3.x). I noticed that it uses Taylor/Maclaurin polynomials to approximate the sine, cosine, tangent, and inverse tangent functions. Wouldn't CORDIC be a better algorithm for computing trigonometric and exponential functions instead? CORDIC is a method for calculating mathematical functions using only addition, shifting, and looking up entries in a table. More details can be found at http://www.ezcomm.com/%7Ecyliax/Articles/RobNav/sidebar.html Thanks, --Arthur - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/