Re: NonlinearFit not reaching convergence, even after spoon-feeding it with initial parameters.
- To: mathgroup at smc.vnet.net
- Subject: [mg45898] Re: NonlinearFit not reaching convergence, even after spoon-feeding it with initial parameters.
- From: Paul Abbott <paul at physics.uwa.edu.au>
- Date: Thu, 29 Jan 2004 05:34:46 -0500 (EST)
- Organization: The University of Western Australia
- References: <bv835f$iab$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
In article <bv835f$iab$1 at smc.vnet.net>, gilmar.rodriguez at nwfwmd.state.fl.us (Gilmar Rodr?guez Pierluissi) wrote: > My questions are: > (1.) How can I control the NUMBER OF ITERATIONS in NonlinearFit? > (2.) How can I control the STEPSIZE in NonlinearFit? > (3.) How can I control the TOLERANCE in NonlinearFit? > (4.) Notice that I "spoon fed" NonlinearFit the above initial > parameters (which I know work fine), and I still > get a warning message! How can I remedy this situation? I suggest that you look up the documentation for FindFit instead (which NonlinearFit uses in 5.0). Since your data is experimental you cannot eliminate the accuracy warning message unless you reduce the AccuracyGoal. See http://physics.uwa.edu.au/pub/Mathematica/MathGroup/NonlinearFitting.nb for some more comments on your problem. Cheers, Paul -- Paul Abbott Phone: +61 8 9380 2734 School of Physics, M013 Fax: +61 8 9380 1014 The University of Western Australia (CRICOS Provider No 00126G) 35 Stirling Highway Crawley WA 6009 mailto:paul at physics.uwa.edu.au AUSTRALIA http://physics.uwa.edu.au/~paul