From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 31652 invoked by alias); 3 Jan 2008 15:54:41 -0000 Received: (qmail 31642 invoked by uid 22791); 3 Jan 2008 15:54:41 -0000 X-Spam-Check-By: sourceware.org Received: from mail.network-theory.co.uk (HELO mail.network-theory.co.uk) (66.199.228.187) by sourceware.org (qpsmtpd/0.31) with ESMTP; Thu, 03 Jan 2008 15:49:30 +0000 Date: Thu, 03 Jan 2008 15:54:00 -0000 Message-ID: <87ejcync3o.wl%bjg@network-theory.co.uk> From: Brian Gough To: Frank Reininghaus Cc: gsl-discuss@sourceware.org Subject: Re: Bug report and fix for adaptive step size control in ODE solving In-Reply-To: <4772D239.9070206@googlemail.com> References: <4772D239.9070206@googlemail.com> User-Agent: Wanderlust/2.14.0 (Africa) Emacs/22.1 Mule/5.0 (SAKAKI) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII X-Message-Mac: c89ad7645bc035b48a37c83255bd6e75 Mailing-List: contact gsl-discuss-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gsl-discuss-owner@sourceware.org X-SW-Source: 2008-q1/txt/msg00005.txt.bz2 At Wed, 26 Dec 2007 23:14:17 +0100, Frank Reininghaus wrote: > I've found some problems with adaptive step size control which can > lead to an infinite loop under special circumstances. I've attached > three test case programs where the rhs of the ODE to be solved is a > step function. All programs lead to infinite loops either in the the > loop in my code (which should be equivalent to the loop in the example > program > in the documentation) or in gsl_odeiv_evolve_apply () (in the file > ode-initval/evolve.c) for different reasons. Thanks for the bug report. This is really useful. I am adding the examples to the test suite right now. Then I'll see what the best solution is. -- Brian Gough