From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 28134 invoked by alias); 29 Sep 2006 17:01:25 -0000 Received: (qmail 28114 invoked by uid 22791); 29 Sep 2006 17:01:22 -0000 X-Spam-Check-By: sourceware.org Received: from smtp6.libero.it (HELO smtp6.libero.it) (193.70.192.59) by sourceware.org (qpsmtpd/0.31) with ESMTP; Fri, 29 Sep 2006 17:01:17 +0000 Received: from localhost (172.16.1.47) by smtp6.libero.it (7.0.027-DD01) id 451C4E690015A81C for gsl-discuss@sourceware.org; Fri, 29 Sep 2006 19:01:14 +0200 Received: from smtp2.libero.it ([172.16.1.225]) by localhost (asav7.libero.it [193.70.193.93]) (amavisd-new, port 10024) with ESMTP id 02817-03 for ; Fri, 29 Sep 2006 19:01:13 +0200 (CEST) Received: from aragorn.bottazzihome.org (adsl-ull-76-244.46-151.net24.it [151.46.244.76]) by smtp2.libero.it (Postfix) with SMTP id 23AF2A8C28 for ; Fri, 29 Sep 2006 19:01:13 +0200 (MEST) Date: Fri, 29 Sep 2006 17:01:00 -0000 From: Giulio Bottazzi To: gsl-discuss@sourceware.org Subject: problem with gsl_sf_lnpoch Message-Id: <20060929190112.49d85f61.giulio.bottazzi@libero.it> X-Mailer: Sylpheed version 2.2.9 (GTK+ 2.8.19; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: multipart/signed; protocol="application/pgp-signature"; micalg="PGP-SHA1"; boundary="Signature=_Fri__29_Sep_2006_19_01_12_+0200_ATYlgBNxGGMeO9Hq" X-Scanned: with antispam and antivirus automated system at libero.it Mailing-List: contact gsl-discuss-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gsl-discuss-owner@sourceware.org X-SW-Source: 2006-q3/txt/msg00035.txt.bz2 --Signature=_Fri__29_Sep_2006_19_01_12_+0200_ATYlgBNxGGMeO9Hq Content-Type: text/plain; charset=US-ASCII Content-Disposition: inline Content-Transfer-Encoding: 7bit Content-length: 769 Hi, It seems that the exponential of the logarithm of the Pochhammer symbol with second argument equal to zero is NOT one. Consider the following little program, which should print two times the number 1 separated by a space /* -- START test.c */ #include #include #include int main(){ printf("exp(log(poch))=%g poch=%g\n", exp( gsl_sf_lnpoch(7,0)),gsl_sf_poch(7,0)); return 0; } /* -- END test.c */ If I compile it with #gcc -Wall test.c -lgsl -lgslcblas -lm -o test and run #./test I get: #exp(log(poch))=2.71828 poch=1 What's going on? I can't see any mistake in my code. Best, Giulio. -- Giulio Bottazzi PGP Key ID:BAB0A33F giulio.bottazzi@libero.it http://www.sssup.it/~bottazzi --Signature=_Fri__29_Sep_2006_19_01_12_+0200_ATYlgBNxGGMeO9Hq Content-Type: application/pgp-signature Content-length: 189 -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (GNU/Linux) iD8DBQFFHVFY83eEJLqwoz8RAmE4AJ9o8EqQJAtFvd55nZSh18HbPnPsfQCfWulm wp22W21BMdKoAzZszJNpE+g= =XNxD -----END PGP SIGNATURE----- --Signature=_Fri__29_Sep_2006_19_01_12_+0200_ATYlgBNxGGMeO9Hq--