1/* mpc_proj -- projection of a complex number onto the Riemann sphere.
2
3Copyright (C) 2008, 2009, 2011 INRIA
4
5This file is part of GNU MPC.
6
7GNU MPC is free software; you can redistribute it and/or modify it under
8the terms of the GNU Lesser General Public License as published by the
9Free Software Foundation; either version 3 of the License, or (at your
10option) any later version.
11
12GNU MPC is distributed in the hope that it will be useful, but WITHOUT ANY
13WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
14FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for
15more details.
16
17You should have received a copy of the GNU Lesser General Public License
18along with this program. If not, see http://www.gnu.org/licenses/ .
19*/
20
21#include "mpc-impl.h"
22
23int
24mpc_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