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