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| author | vlefevre <vlefevre@280ebfd0-de03-0410-8827-d642c229c3f4> | 2014-01-17 23:00:51 +0000 |
|---|---|---|
| committer | vlefevre <vlefevre@280ebfd0-de03-0410-8827-d642c229c3f4> | 2014-01-17 23:00:51 +0000 |
| commit | ea192952b341fab0134ad46ff1e7c8c7d4195ebb (patch) | |
| tree | a33c314f09cf553e57f323b1763b34b61935bf5b /src/digamma.c | |
| parent | ad490b5177f9e8271f15978884c9f4efa9beccb0 (diff) | |
| download | mpfr-ea192952b341fab0134ad46ff1e7c8c7d4195ebb.tar.gz | |
[src/digamma.c] FIXME: for x large, use the asymptotic expansion.
git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/trunk@8767 280ebfd0-de03-0410-8827-d642c229c3f4
Diffstat (limited to 'src/digamma.c')
| -rw-r--r-- | src/digamma.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/src/digamma.c b/src/digamma.c index 7b8e04a65..57dcae865 100644 --- a/src/digamma.c +++ b/src/digamma.c @@ -217,6 +217,10 @@ mpfr_digamma_positive (mpfr_ptr y, mpfr_srcptr x, mpfr_rnd_t rnd_mode) (("x[%Pu]=%.*Rg rnd=%d", mpfr_get_prec(x), mpfr_log_prec, x, rnd_mode), ("y[%Pu]=%.*Rg inexact=%d", mpfr_get_prec(y), mpfr_log_prec, y, inex)); + /* FIXME: for x large, use the asymptotic expansion: + https://en.wikipedia.org/wiki/Digamma_function#Computation_and_approximation + */ + /* compute a precision q such that x+1 is exact */ if (MPFR_PREC(x) < MPFR_EXP(x)) q = MPFR_EXP(x); |