From owner-freebsd-numerics@FreeBSD.ORG Tue Aug 14 18:47:17 2012 Return-Path: Delivered-To: freebsd-numerics@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 9EB6C106564A for ; Tue, 14 Aug 2012 18:47:17 +0000 (UTC) (envelope-from stephen@missouri.edu) Received: from wilberforce.math.missouri.edu (wilberforce.math.missouri.edu [128.206.184.213]) by mx1.freebsd.org (Postfix) with ESMTP id 6680F8FC14 for ; Tue, 14 Aug 2012 18:47:16 +0000 (UTC) Received: from [127.0.0.1] (wilberforce.math.missouri.edu [128.206.184.213]) by wilberforce.math.missouri.edu (8.14.5/8.14.5) with ESMTP id q7EIlGht050538; Tue, 14 Aug 2012 13:47:16 -0500 (CDT) (envelope-from stephen@missouri.edu) Message-ID: <502A9D34.7070203@missouri.edu> Date: Tue, 14 Aug 2012 13:47:16 -0500 From: Stephen Montgomery-Smith User-Agent: Mozilla/5.0 (X11; Linux i686; rv:14.0) Gecko/20120714 Thunderbird/14.0 MIME-Version: 1.0 To: Steve Kargl References: <502A8CCC.5080606@missouri.edu> <20120814175257.GA69865@troutmask.apl.washington.edu> In-Reply-To: <20120814175257.GA69865@troutmask.apl.washington.edu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-numerics@freebsd.org Subject: Re: Status of expl logl X-BeenThere: freebsd-numerics@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Discussions of high quality implementation of libm functions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 14 Aug 2012 18:47:17 -0000 On 08/14/2012 12:52 PM, Steve Kargl wrote: > It is much easier to read Tang's papers, and implement his > algorithms. Then, you send the code to Bruce and watch > the optimization machine churn over the code. :-) > > PTP Tang, "Table-Driven Implementation of the Expml Function In IEEE > Floating-Point Arithmetic," ACM Trans. Math. Soft., 18, 1992, > 211-222. > > PTP Tang, "Table-Driven Implementation of the Exponential Function > in IEEE Floating-Point Arithmetic," ACM Trans. Math. Soft., 15, 1989, > 144-157. > > PTP Tang, "Table-Driven Implementation of the Logarithm Function in IEEE > Floating-Point Arithmetic," ACM Trans. Math. Soft., 16, 1990, 378-400. > That must be the same Tang who co-wrote the paper with Hull and Fairgrieve on the arcsin. I had an email conversation with Fairgrieve a few days ago, because I wanted to know if they had written a paper on the arctan. It turned out that Hull died soon after the paper on arcsine was completed. Fairgrieve sent me the paper on arctan, which they neither completed nor published. He doesn't want it spread widely because I think he wants to publish it one day. But it is very similar to the algorithm I developed myself for catanh. I do have a bad habit of trying to create the mathematics for myself, and internally I consider it cheating to read the literature. This habit has bitten me several times in the past, and I have had papers rejected because I didn't properly cite the existing literature, and had reinvented the wheel.