Re: What to do about tgammal?
- Reply: Mark Murray : "Re: What to do about tgammal?"
- In reply to: Mark Murray : "Re: What to do about tgammal?"
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Date: Sat, 18 Dec 2021 03:52:22 UTC
On Tue, Dec 14, 2021 at 10:21:55PM +0000, Mark Murray wrote: > On 14 Dec 2021, at 21:51, Steve Kargl <sgk@troutmask.apl.washington.edu> wrote: > > Interval max ULP x at Max ULP > > [6,1755.1] 0.873414 at 1.480588145237629047468e+03 > > [1.0662,6] 0.861508 at 1.999467927053585410537e+00 > > [1.01e-17,1.0661] 0.938041 at 1.023286481537296307856e+00 > > [-1.9999,-1.0001] 3.157770 at -1.246957268051453610329e+00 > > [-2.9999,-2.0001] 2.987659 at -2.220949465449893090070e+00 > > > > Note, 1.01e-17 can be reduced to soemthing like 1.01e-19 or > > Extra diffs most welcome! > Hi Mark, Don't know if you noticed, but I borroewed a few cpu cycles from grimoire. My WIP is already better than the imprecise.c kludge from theraven@. I need to work out the details of computing logl(x) in extra precision or see if I can leverage what Bruce did a few years ago. Anywho, current results: Interval tested for tgammal: [128,1755] count: 1000000 xm = 1.71195767195767195767195767195767183e+03L libm = 7.79438030237108165017007606176403036e+4790L mpfr = 7.79438030237108165017007606175285456e+4790L ULP = 14869.19517 Interval tested for tgammal: [16,128] count: 1000000 xm = 1.27687183687183687183687183687183690e+02L libm = 6.61421998891483212224382625339007663e+212L mpfr = 6.61421998891483212224382625338960267e+212L ULP = 731.00958 Interval tested for tgammal: [10,16] count: 1000000 xm = 1.54261654261654261654261654261654251e+01L libm = 2.74203137295418912508367515208072654e+11L mpfr = 2.74203137295418912508367515208073861e+11L ULP = 45.61161 Interval tested for tgammal: [1.2446e-60,10] count: 1000000 xm = 6.26200626138006138006138006138006065e-02L libm = 1.54507103764516989381203274093299079e+01L mpfr = 1.54507103764516989381203274093299091e+01L ULP = 0.76751 -- Steve