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Re: sf_gamma questions
Jonathan Leto writes:
> --- gamma.c.orig Mon Dec 3 23:21:36 2001
> +++ gamma.c Mon Dec 3 23:53:27 2001
> @@ -1247,7 +1247,14 @@
> int
> gsl_sf_gamma_e(const double x, gsl_sf_result * result)
> {
> + /* if x is an integer as far as we can tell, return factorial(x-1)
> + this gives us much better precision when x>19 or so */
> + if(y < GSL_DBL_EPSILON ){
> + gsl_sf_fact_e((int) x - 1,result);
Thanks. I've added something along these lines but in the function
gamma_xgthalf, which is used in several places and so gives some other
opportunities to gain from a bit of extra accuracy.
Brian