1*d30dc8cbSJohn Marino /* mpc_mul_i -- Multiply a complex number by plus or minus i.
2*d30dc8cbSJohn Marino
3*d30dc8cbSJohn Marino Copyright (C) 2005, 2009, 2010, 2011 INRIA
4*d30dc8cbSJohn Marino
5*d30dc8cbSJohn Marino This file is part of GNU MPC.
6*d30dc8cbSJohn Marino
7*d30dc8cbSJohn Marino GNU MPC is free software; you can redistribute it and/or modify it under
8*d30dc8cbSJohn Marino the terms of the GNU Lesser General Public License as published by the
9*d30dc8cbSJohn Marino Free Software Foundation; either version 3 of the License, or (at your
10*d30dc8cbSJohn Marino option) any later version.
11*d30dc8cbSJohn Marino
12*d30dc8cbSJohn Marino GNU MPC is distributed in the hope that it will be useful, but WITHOUT ANY
13*d30dc8cbSJohn Marino WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
14*d30dc8cbSJohn Marino FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for
15*d30dc8cbSJohn Marino more details.
16*d30dc8cbSJohn Marino
17*d30dc8cbSJohn Marino You should have received a copy of the GNU Lesser General Public License
18*d30dc8cbSJohn Marino along with this program. If not, see http://www.gnu.org/licenses/ .
19*d30dc8cbSJohn Marino */
20*d30dc8cbSJohn Marino
21*d30dc8cbSJohn Marino #include "mpc-impl.h"
22*d30dc8cbSJohn Marino
23*d30dc8cbSJohn Marino int
mpc_mul_i(mpc_ptr a,mpc_srcptr b,int sign,mpc_rnd_t rnd)24*d30dc8cbSJohn Marino mpc_mul_i (mpc_ptr a, mpc_srcptr b, int sign, mpc_rnd_t rnd)
25*d30dc8cbSJohn Marino /* if sign is >= 0, multiply by i, otherwise by -i */
26*d30dc8cbSJohn Marino {
27*d30dc8cbSJohn Marino int inex_re, inex_im;
28*d30dc8cbSJohn Marino mpfr_t tmp;
29*d30dc8cbSJohn Marino
30*d30dc8cbSJohn Marino /* Treat the most probable case of compatible precisions first */
31*d30dc8cbSJohn Marino if ( MPC_PREC_RE (b) == MPC_PREC_IM (a)
32*d30dc8cbSJohn Marino && MPC_PREC_IM (b) == MPC_PREC_RE (a))
33*d30dc8cbSJohn Marino {
34*d30dc8cbSJohn Marino if (a == b)
35*d30dc8cbSJohn Marino mpfr_swap (mpc_realref (a), mpc_imagref (a));
36*d30dc8cbSJohn Marino else
37*d30dc8cbSJohn Marino {
38*d30dc8cbSJohn Marino mpfr_set (mpc_realref (a), mpc_imagref (b), GMP_RNDN);
39*d30dc8cbSJohn Marino mpfr_set (mpc_imagref (a), mpc_realref (b), GMP_RNDN);
40*d30dc8cbSJohn Marino }
41*d30dc8cbSJohn Marino if (sign >= 0)
42*d30dc8cbSJohn Marino MPFR_CHANGE_SIGN (mpc_realref (a));
43*d30dc8cbSJohn Marino else
44*d30dc8cbSJohn Marino MPFR_CHANGE_SIGN (mpc_imagref (a));
45*d30dc8cbSJohn Marino inex_re = 0;
46*d30dc8cbSJohn Marino inex_im = 0;
47*d30dc8cbSJohn Marino }
48*d30dc8cbSJohn Marino else
49*d30dc8cbSJohn Marino {
50*d30dc8cbSJohn Marino if (a == b)
51*d30dc8cbSJohn Marino {
52*d30dc8cbSJohn Marino mpfr_init2 (tmp, MPC_PREC_RE (a));
53*d30dc8cbSJohn Marino if (sign >= 0)
54*d30dc8cbSJohn Marino {
55*d30dc8cbSJohn Marino inex_re = mpfr_neg (tmp, mpc_imagref (b), MPC_RND_RE (rnd));
56*d30dc8cbSJohn Marino inex_im = mpfr_set (mpc_imagref (a), mpc_realref (b), MPC_RND_IM (rnd));
57*d30dc8cbSJohn Marino }
58*d30dc8cbSJohn Marino else
59*d30dc8cbSJohn Marino {
60*d30dc8cbSJohn Marino inex_re = mpfr_set (tmp, mpc_imagref (b), MPC_RND_RE (rnd));
61*d30dc8cbSJohn Marino inex_im = mpfr_neg (mpc_imagref (a), mpc_realref (b), MPC_RND_IM (rnd));
62*d30dc8cbSJohn Marino }
63*d30dc8cbSJohn Marino mpfr_clear (mpc_realref (a));
64*d30dc8cbSJohn Marino mpc_realref (a)[0] = tmp [0];
65*d30dc8cbSJohn Marino }
66*d30dc8cbSJohn Marino else
67*d30dc8cbSJohn Marino if (sign >= 0)
68*d30dc8cbSJohn Marino {
69*d30dc8cbSJohn Marino inex_re = mpfr_neg (mpc_realref (a), mpc_imagref (b), MPC_RND_RE (rnd));
70*d30dc8cbSJohn Marino inex_im = mpfr_set (mpc_imagref (a), mpc_realref (b), MPC_RND_IM (rnd));
71*d30dc8cbSJohn Marino }
72*d30dc8cbSJohn Marino else
73*d30dc8cbSJohn Marino {
74*d30dc8cbSJohn Marino inex_re = mpfr_set (mpc_realref (a), mpc_imagref (b), MPC_RND_RE (rnd));
75*d30dc8cbSJohn Marino inex_im = mpfr_neg (mpc_imagref (a), mpc_realref (b), MPC_RND_IM (rnd));
76*d30dc8cbSJohn Marino }
77*d30dc8cbSJohn Marino }
78*d30dc8cbSJohn Marino
79*d30dc8cbSJohn Marino return MPC_INEX(inex_re, inex_im);
80*d30dc8cbSJohn Marino }
81