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Re: [gfortran] patch for output of real values on windows systems
- From: Ian Lance Taylor <ian at airs dot com>
- To: FX Coudert <fxcoudert at gmail dot com>
- Cc: gfortran <fortran at gcc dot gnu dot org>, patch <gcc-patches at gcc dot gnu dot org>
- Date: 05 Aug 2005 21:29:58 -0700
- Subject: Re: [gfortran] patch for output of real values on windows systems
- References: <42F3E148.9090904@gmail.com>
FX Coudert <fxcoudert@gmail.com> writes:
> The provided fallback sprintf is not perfect: it prints incorrect last
> digits (at least, not similar to those printed by GNU libc) when used
> to output very large or very small long double values with high
> precision (more than 15 digits). Any practical suggestion on this is
> welcome.
newlib (http://sourceware.org/newlib/) includes an implementation of
dtoa, originally by David Gay, which is said to correctly represent
floating point values, based on Steele and White's algorithm. It's in
newlib/libc/stdlib/dtoa.c. The original version is probably available
from netlib. There is similar code in other free C libraries.
There's no need to roll your own code to convert floating point values
to printable form.
Ian