At Wed, 11 Jun 2008 12:31:39 +0100, Jonny Taylor wrote: > I don't know what the policy is regarding optimizations which > (slightly) decrease code readability, but there's a simple change to > the downward recurrence in gsl_sf_bessel_Jn_e which doubles the speed > of the function (almost all the remaining time is spent in > gsl_sf_bessel_J_CF1) for n of order 10-40.
Thanks for your email. That is interesting. Can you give a few more details about the compilation options you used, compiler version and the platform. Did you see how much of the benefit comes from replacing 2/x by a constant compared with keeping the value of k in a double? The optimisation of replacing (2/x) by a constant would be something I would expect GCC to deduce at some level. -- Brian Gough _______________________________________________ Bug-gsl mailing list [email protected] http://lists.gnu.org/mailman/listinfo/bug-gsl
