From: Brian Gough <bjg@network-theory.co.uk>
To: GSL Discuss Mailing List <gsl-discuss@sourceware.org>
Subject: difficult region for gsl_sf_hyperg_1F1
Date: Tue, 15 Dec 2009 18:36:00 -0000 [thread overview]
Message-ID: <87bpi0gm8m.wl%bjg@network-theory.co.uk> (raw)
We have gsl_sf_hyperg1F1(-37.8, 2.01, 103.58) => -3.16661e+14 +/-
3.31+19 from the series. Correct answer is -6.21927211009e17(*).
Does anyone know a better algorithm for this region?
http://savannah.gnu.org/bugs/?28267
(*) In pari:
poch(a,x) = { gamma(a+x)/gamma(a) }
t(a,b,x,k) = { (poch(a,k)/poch(b,k)) * (x^k)/(k!) }
suminf(k=0,t(-37.8,2.01,103.58,k))
reply other threads:[~2009-12-15 18:36 UTC|newest]
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