Hi 2012/8/16 Gilles Sadowski <gil...@harfang.homelinux.org>: > On Wed, Aug 15, 2012 at 04:58:39PM +0200, Sébastien Brisard wrote: >> Dear All, >> I'm currently working on accuracy improvements of the incomplete beta >> function, based on the NSWC library [1]. It's quite a long work, but it >> looks promising, since the implementation of the Gamma function they >> propose (I had to work first on Gamma before starting the actual work on >> Beta) seems to be much more accurate than the current implementation in CM3 >> (3-4 ulps, TBC). >> >> When I'm done, I think I will replace the current impl of Gamma with the >> NSWC. The problem is that a few months ago, while working on MATH-753, I >> exposed a few constants as well as the method lanczos, which will probably >> no longer be necessary (NSWC does not use Lanczos, but minimax rational >> approximations). My worry is that we are approaching the release of 3.1, >> and I think it would be a shame if we froze the exposition of these >> constants and methods. The trouble is that my current work on Gamma and >> Beta is quite slow, I'm not sure I can finish it before the expected >> release. >> >> So, should I revert the changes made for MATH-753, and reopen this issue? >> This would allow the removal of method lanczos and constant LANCZOS_G, > > For traceability, that could be a good idea to indicate in MATH-753 that you > changed your mind, and decided to make those "private". ;-) > For the time being, I can't make these fields private, because they are needed by other classes (GammaDistribution), which are not even in the same package. So basically, once I've reimplemented Gamma, I need to find another fix to MATH-753...
>> which would lay out the path to the new implementation. Alternatively, I >> can deprecate these fields. > > Not necessary to go through this step since those fields appeared after the > last release (IIRC). > Yes. My concern is that you want to release soon, and I'm not sure I can clean this up before release. Fortunately, progress has been smooth on the Gamma side those last days. So, instead of working on MATH-738 (which all this is about), I will concentrate on replacing the old impl of Gamma with the new one, and re-fixing MATH-753. Hopefully this will all happen soon! Sébastien > > Regards, > Gilles > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > For additional commands, e-mail: dev-h...@commons.apache.org > --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
