Martin, try the simplex minimizers too. I found it more powerful for certain functions.The only drawback is that you can't compute the covariance matrix of the theoretical parameters.
Also, some experimentation may be required to find the optimal initial step size. I personally followed a twofold approach for a recent small program: simplex first to find the minimum, then Levenberg-Marquardt to get some statistics. As far as it can help, here's my code (sorry, no autoconf: edit the Makefile as you need....) http://www.studenti.unina.it/~gcderosa/scanning-tunneling/dIdVsuperc.tar.gz What matters for the current discussion is mainly in fit.c . For the impatient, I also shared a screencast :-) http://youtube.com/watch?v=LLLq7-0DivI HTH, Guido _______________________________________________ Help-gsl mailing list [email protected] http://lists.gnu.org/mailman/listinfo/help-gsl
