From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 31785 invoked by alias); 3 Nov 2002 15:17:32 -0000 Mailing-List: contact gsl-discuss-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gsl-discuss-owner@sources.redhat.com Received: (qmail 31664 invoked from network); 3 Nov 2002 15:17:31 -0000 Received: from unknown (HELO blueyonder.co.uk) (195.188.53.121) by sources.redhat.com with SMTP; 3 Nov 2002 15:17:31 -0000 Received: from pcow035o.blueyonder.co.uk ([127.0.0.1]) by blueyonder.co.uk with Microsoft SMTPSVC(5.5.1877.757.75); Sun, 3 Nov 2002 15:17:31 +0000 Received: from localhost (unverified [62.30.73.101]) by pcow035o.blueyonder.co.uk (Content Technologies SMTPRS 4.2.9) with ESMTP id ; Sun, 3 Nov 2002 15:17:30 +0000 Received: by network-theory.co.uk via sendmail from stdin id (Debian Smail3.2.0.102) for babansky@mail.ru; Sun, 3 Nov 2002 15:05:00 +0000 (GMT) From: Brian Gough MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Message-ID: <15813.15130.826338.584075@debian> Date: Sun, 03 Nov 2002 22:11:00 -0000 To: "Alexander Babansky" Cc: Subject: Re: gsl-1.2 In-Reply-To: <000501c28242$fced2e90$8aa60a44@home1> References: <000501c28242$fced2e90$8aa60a44@home1> X-SW-Source: 2002-q4/txt/msg00101.txt.bz2 Alexander Babansky writes: > Hi, I've found a small bug in Ei(x) function Reference > manual(section Exponential Integral) In definition of Ei(x) it > should be: Ei(x) := - PV(\int_{-x}^\infty dt \exp(-t)/t) (with "-" > sign). > True mathematical definition of Ei(x) is: Ei(x) := > PV(\int_{-infinity}^x dt \exp(t)/t When you change varibles, x-> -x > you will get that "-" sign. Bug is only in Reference manual not in > Ei(x) itself. Thanks, I'll correct it. regards Brian Gough