mpf/get_d.c


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/* double mpf_get_d (mpf_t src) -- return SRC truncated to a double.

Copyright 1996, 2001-2004 Free Software Foundation, Inc.

This file is part of the GNU MP Library.

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

The GNU MP Library 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 Lesser General Public
License for more details.

You should have received a copy of the GNU Lesser General Public License
along with the GNU MP Library.  If not, see https://www.gnu.org/licenses/.  */

#include "gmp.h"
#include "gmp-impl.h"

double
mpf_get_d (mpf_srcptr src)
{
  mp_size_t  size, abs_size;
  long       exp;

  size = SIZ (src);
  if (UNLIKELY (size == 0))
    return 0.0;

  abs_size = ABS (size);
  exp = (EXP (src) - abs_size) * GMP_NUMB_BITS;
  return mpn_get_d (PTR (src), abs_size, size, exp);
}