1/* mpz_set_f (dest_integer, src_float) -- Assign DEST_INTEGER from SRC_FLOAT.
2
3Copyright 1996, 2001 Free Software Foundation, Inc.
4
5This file is part of the GNU MP Library.
6
7The GNU MP Library is free software; you can redistribute it and/or modify
8it under the terms of the GNU Lesser General Public License as published by
9the Free Software Foundation; either version 3 of the License, or (at your
10option) any later version.
11
12The GNU MP Library is distributed in the hope that it will be useful, but
13WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
14or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
15License for more details.
16
17You should have received a copy of the GNU Lesser General Public License
18along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.  */
19
20#include "gmp.h"
21#include "gmp-impl.h"
22
23
24void
25mpz_set_f (mpz_ptr w, mpf_srcptr u)
26{
27  mp_ptr    wp, up;
28  mp_size_t size;
29  mp_exp_t  exp;
30
31  /* abs(u)<1 truncates to zero */
32  exp = EXP (u);
33  if (exp <= 0)
34    {
35      SIZ(w) = 0;
36      return;
37    }
38
39  MPZ_REALLOC (w, exp);
40  wp = PTR(w);
41  up = PTR(u);
42
43  size = SIZ (u);
44  SIZ(w) = (size >= 0 ? exp : -exp);
45  size = ABS (size);
46
47  if (exp > size)
48    {
49      /* pad with low zeros to get a total "exp" many limbs */
50      mp_size_t  zeros = exp - size;
51      MPN_ZERO (wp, zeros);
52      wp += zeros;
53    }
54  else
55    {
56      /* exp<=size, trucate to the high "exp" many limbs */
57      up += (size - exp);
58      size = exp;
59    }
60
61  MPN_COPY (wp, up, size);
62}
63