Re: [Gretl-users] autoreg formula and bessel function
On Sun, 14 Jun 2009, Klein, Christoph wrote:
[F]or my diploma thesis I have added a command to gretl which
computes the bessel function. The function is implemented using
the gsl library. I would like to contribute this to gretl, too,
but I don't know how you feel about linking against gsl?
I have now added the cephes Bessel-function code to the gretl code
base; the relevant functionality is now present in "raw" form.
I'm putting a sample C program plus Makefile in
http://www.wfu.edu/~/cottrell/bessel/
On running the program 'bessel' (which links against libgretl) you
get a set of *.txt data files which can be displayed in gnuplot
using the *.gp files in the same directory.
One could take the sample program as a basis for adding a
gretl_bessel function (maybe to lib/src/genfuncs.c), and then work
out a user interface.
While it may make sense to have dozens of "bessel" functions in
the libgsl API, I think we'd want just one function for gretl's
user-space. Perhaps a three-parameter function, with arguments n
(could be fractional), x, and a code of some sort for the type of
function (J, Y, I, K, etc.).
Allin Cottrell