I'm not very familiar with the bessel function and numerical calculation of it, but I think in the mentioned range it works quite well. If you need a more professional implementation I could copy'n' paste the gsl code into a new function for gretl. I think gsl and gretl both use GPL3. I *really* need besselK for fractional orders :) Christoph ________________________________________ Von: gretl-users-bounces(a)lists.wfu.edu [gretl-users-bounces(a)lists.wfu.edu] im Auftrag von Allin Cottrell [cottrell(a)wfu.edu] Gesendet: Donnerstag, 18. Juni 2009 05:27 An: Gretl list Betreff: Re: [Gretl-users] bessel functions On Wed, 17 Jun 2009, Klein, Christoph wrote: Wow! How great to get such a well worked-out patch! I have added to CVS most of what you submitted, in a slightly trimmed-down version that (for now) only accepts a scalar value for the order of the Bessel function. Nice! I'll check against libgsl too. On an initial scan it seems that most things are fine but the Bessel 'K' function goes a bit strange for large values of X (as you say, values < 20 are OK). Allin Cottrell _______________________________________________ Gretl-users mailing list Gretl-users(a)lists.wfu.edu http://lists.wfu.edu/mailman/listinfo/gretl-users