1 /* mpc_proj -- projection of a complex number onto the Riemann sphere.
2
3 Copyright (C) 2008, 2009, 2011 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
mpc_proj(mpc_ptr a,mpc_srcptr b,mpc_rnd_t rnd)24 mpc_proj (mpc_ptr a, mpc_srcptr b, mpc_rnd_t rnd)
25 {
26 if (mpc_inf_p (b)) {
27 /* infinities project to +Inf +i* copysign(0.0, cimag(z)) */
28 mpfr_set_inf (mpc_realref (a), +1);
29 mpfr_set_zero (mpc_imagref (a), (mpfr_signbit (mpc_imagref (b)) ? -1 : 1));
30 return MPC_INEX (0, 0);
31 }
32 else
33 return mpc_set (a, b, rnd);
34 }
35