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Re: Help with math calculation (regression) needed
- From: "Joseph S. Myers" <joseph at codesourcery dot com>
- To: Andreas Jaeger <aj at suse dot de>
- Cc: libc-alpha at sourceware dot org
- Date: Mon, 4 Jul 2011 11:26:38 +0000 (UTC)
- Subject: Re: Help with math calculation (regression) needed
- References: <201107022140.23697.aj@suse.de>
On Sat, 2 Jul 2011, Andreas Jaeger wrote:
> I just did some investigation into a bug with the bessel jn functions:
> http://sourceware.org/bugzilla/show_bug.cgi?id=11589
>
> The fix is ok - and now I'd like to add some regression tests but do not have
> access anymore to maple calculate myself accurate numbers - and AFAIK octave
> and scilab are not doing precise enough calculations for long double.
>
> Can any body help and calculate to 35 digits the following:
> BesselJ (N, 2.4048255576957729)
> for values 3 to 9 for N?
FWIW, GNU MPFR supports Bessel functions of integer order, correctly
rounded to any precision, as well as all the C99 standard mathematical
functions (MPC provides those with complex arguments). (It doesn't
support fractional-order Bessel functions, but neither does glibc; the
fractional-order functions are in ISO 24747, Extensions to the C Library,
to Support Mathematical Special Functions, but not in standard C itself or
traditional Unix libm.)
--
Joseph S. Myers
joseph@codesourcery.com