xref: /dragonfly/contrib/mpc/src/fr_sub.c (revision d30dc8cb)
1 /* mpc_fr_sub -- Substract a complex number from a floating-point number.
2 
3 Copyright (C) 2008, 2009, 2011, 2012 INRIA
4 
5 This file is part of GNU MPC.
6 
7 GNU MPC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU Lesser General Public License as published by the
9 Free Software Foundation; either version 3 of the License, or (at your
10 option) any later version.
11 
12 GNU MPC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
14 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for
15 more details.
16 
17 You should have received a copy of the GNU Lesser General Public License
18 along with this program. If not, see http://www.gnu.org/licenses/ .
19 */
20 
21 #include "mpc-impl.h"
22 
23 /* return 0 iff both the real and imaginary parts are exact */
24 int
mpc_fr_sub(mpc_ptr a,mpfr_srcptr b,mpc_srcptr c,mpc_rnd_t rnd)25 mpc_fr_sub (mpc_ptr a, mpfr_srcptr b, mpc_srcptr c, mpc_rnd_t rnd)
26 {
27   int inex_re, inex_im;
28 
29   inex_re = mpfr_sub (mpc_realref (a), b, mpc_realref (c), MPC_RND_RE (rnd));
30   inex_im = mpfr_neg (mpc_imagref (a), mpc_imagref (c), MPC_RND_IM (rnd));
31 
32   return MPC_INEX(inex_re, inex_im);
33 }
34