view lib/modfl.c @ 17249:e542fd46ad6f

maint: update all copyright year number ranges Run "make update-copyright". Compare to commit 1602f0a from last year. Signed-off-by: Eric Blake <eblake@redhat.com>
author Eric Blake <eblake@redhat.com>
date Tue, 01 Jan 2013 00:50:58 +0000
parents d2bb16b4df01
children 344018b6e5d7
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/* Get signed integer and fractional parts of a floating-point number.
   Copyright (C) 2012-2013 Free Software Foundation, Inc.

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include <config.h>

/* Specification.  */
#include <math.h>

#if HAVE_SAME_LONG_DOUBLE_AS_DOUBLE

long double
modfl (long double x, long double *iptr)
{
  double integer_part;
  double fractional_part = modf (x, &integer_part);
  *iptr = integer_part;
  return fractional_part;
}

#else

long double
modfl (long double x, long double *iptr)
{
  if (isfinite (x))
    {
      long double integer_part = truncl (x);
      *iptr = integer_part;
      return x - integer_part;
    }
  else
    {
      if (isinf (x))
        {
          *iptr = x;
          return 1.0L / x;
        }
      else /* isnanl (x) */
        {
          *iptr = x;
          return x;
        }
    }
}

#endif