From chemistry-request -x- at -x- server.ccl.net Mon Mar 3 04:20:28 2003 Received: from darius.ribotargets.com ([194.129.39.11]) by server.ccl.net (8.11.6/8.11.0) with ESMTP id h239KRQ27667 for ; Mon, 3 Mar 2003 04:20:28 -0500 Received: from echo.ribotargets.com (echo [194.129.39.91]) by darius.ribotargets.com (SGI-8.9.3/8.9.3) with ESMTP id JAA01282; Mon, 3 Mar 2003 09:20:05 GMT Received: from szilva (helo=localhost) by echo.ribotargets.com with local-esmtp (Exim 3.13 #1) id 18pm38-0007JD-00; Mon, 03 Mar 2003 09:15:54 +0000 Date: Mon, 3 Mar 2003 09:15:54 +0000 (GMT) From: Szilveszter Juhos To: Pradipta Bandyopadhyay cc: chemistry ":at:" ccl.net Subject: Re: CCL:sofwares for non-linear fitting!! In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII > What are the best softwares (free and for UNIX) to do non-linear > fitting for a very large amount of data? Hello, non-linear fitting is a quite huge topic from fitting simple nonlinear functions to neural-net based stuff. If you have too many points, be aware of the robustness of the procedure. In short if you have too many points at some part of the data, that will be overrepresented biasing the final parameter estimates. Softwares you can try: http://www.octave.org/ "GNU Octave is a high-level language, primarily intended for numerical computations. It provides a convenient command line interface for solving linear and nonlinear problems numerically, and for performing other numerical experiments using a language that is mostly compatible with Matlab." http://plasma-gate.weizmann.ac.il/Grace/ "Grace is a WYSIWYG 2D plotting tool for the X Window System and M*tif. Grace runs on practically any version of Unix-like OS. " (it also has curve fitting capabilities) http://www.gnuplot.info/ Gnuplot itself can do some nonlinear fitting, type "help fit" in its command prompt. Hope it helps: Szilva