xref: /dragonfly/contrib/mpc/src/sinh.c (revision 25a2db75)
1 /* mpc_sinh -- hyperbolic sine of a complex 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 int
24 mpc_sinh (mpc_ptr rop, mpc_srcptr op, mpc_rnd_t rnd)
25 {
26   /* sinh(op) = -i*sin(i*op) = conj(-i*sin(conj(-i*op))) */
27   mpc_t z;
28   mpc_t sin_z;
29   int inex;
30 
31   /* z := conj(-i * op) and rop = conj(-i * sin(z)), in other words, we have
32      to switch real and imaginary parts. Let us set them without copying
33      significands. */
34   mpc_realref (z)[0] = mpc_imagref (op)[0];
35   mpc_imagref (z)[0] = mpc_realref (op)[0];
36   mpc_realref (sin_z)[0] = mpc_imagref (rop)[0];
37   mpc_imagref (sin_z)[0] = mpc_realref (rop)[0];
38 
39   inex = mpc_sin (sin_z, z, MPC_RND (MPC_RND_IM (rnd), MPC_RND_RE (rnd)));
40 
41   /* sin_z and rop parts share the same significands, copy the rest now. */
42   mpc_realref (rop)[0] = mpc_imagref (sin_z)[0];
43   mpc_imagref (rop)[0] = mpc_realref (sin_z)[0];
44 
45   /* swap inexact flags for real and imaginary parts */
46   return MPC_INEX (MPC_INEX_IM (inex), MPC_INEX_RE (inex));
47 }
48