Hello, I think I found what causes this underflow message. It comes from
gsl_sf_hydrogenicR(n,l,Z,r); where l > 0 AND r = 0. Looking at the analytical form of the radial Hydrogenic wavefunction R_nl, in such situations, R_nl is always zero. Which of course gives underflow error. So I suggest that, in the underflow check of gsl_sf_hydrogenicR, one should exclude such situations, and perhaps, which may not be needed, assigns the result to zero directly. Regards, Ivan Liu On Fri, 11 Feb 2005 16:06:20 +0000, Brian Gough <[EMAIL PROTECTED]> wrote: > Ivan Liu writes: > > My program kept being interrupted by the underflow check when I > > compute the coulomb wavefunction with gsl_sf_hydrogenicR. If I turn > > of the error handler then the program returns the seemly correct > > values. > > Can you send a small standalone program which shows the > problem--thanks. (Looking at the function briefly it might be a bug > in the way underflow is tested). > > -- > Brian Gough > > Network Theory Ltd, > Commercial support for GSL --- http://www.network-theory.co.uk/gsl/ > _______________________________________________ Help-gsl mailing list [email protected] http://lists.gnu.org/mailman/listinfo/help-gsl
