Thanks Rhys, at the end I managed in solving the problem.
Now I would like to get the derivative but it seems not to like bspline_deriv and similar: it gives error: gsl_bspline_deriv_workspace was not declared in this scope and I couldn't find, in fact, in the include files these functions ... (I am working with the 1.11 version). I am sorry if it is a stupid question but I don't know what to do! thanks again! CM _______________________________________________ Help-gsl mailing list Help-gsl@gnu.org http://lists.gnu.org/mailman/listinfo/help-gsl
