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author | Pedro Alvarez <pedro.alvarez@codethink.co.uk> | 2016-05-31 10:43:16 +0100 |
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committer | Pedro Alvarez <pedro.alvarez@codethink.co.uk> | 2016-05-31 10:43:16 +0100 |
commit | 7ccad68acf3805b35721e861fb9bc5a9e40effc8 (patch) | |
tree | 311dd8abfb3cf6f42a07f98baeac5f0e950af675 /mpc/src/tanh.c | |
parent | d2a230d1027944e2244aba9a2efe1e3d8b7bc5fc (diff) | |
download | gcc-tarball-baserock/pedroalvarez/gcc-5.3.0.tar.gz |
Import http://www.multiprecision.org/mpc/download/mpc-1.0.3.tar.gzbaserock/pedroalvarez/gcc-5.3.0-v2baserock/pedroalvarez/gcc-5.3.0baserock/gcc-5.3.0
Diffstat (limited to 'mpc/src/tanh.c')
-rw-r--r-- | mpc/src/tanh.c | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/mpc/src/tanh.c b/mpc/src/tanh.c new file mode 100644 index 0000000000..78f21037cf --- /dev/null +++ b/mpc/src/tanh.c @@ -0,0 +1,47 @@ +/* mpc_tanh -- hyperbolic tangent of a complex number. + +Copyright (C) 2008, 2009, 2011, 2012 INRIA + +This file is part of GNU MPC. + +GNU MPC is free software; you can redistribute it and/or modify it under +the terms of the GNU Lesser General Public License as published by the +Free Software Foundation; either version 3 of the License, or (at your +option) any later version. + +GNU MPC is distributed in the hope that it will be useful, but WITHOUT ANY +WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS +FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for +more details. + +You should have received a copy of the GNU Lesser General Public License +along with this program. If not, see http://www.gnu.org/licenses/ . +*/ + +#include "mpc-impl.h" + +int +mpc_tanh (mpc_ptr rop, mpc_srcptr op, mpc_rnd_t rnd) +{ + /* tanh(op) = -i*tan(i*op) = conj(-i*tan(conj(-i*op))) */ + mpc_t z; + mpc_t tan_z; + int inex; + + /* z := conj(-i * op) and rop = conj(-i * tan(z)), in other words, we have + to switch real and imaginary parts. Let us set them without copying + significands. */ + mpc_realref (z)[0] = mpc_imagref (op)[0]; + mpc_imagref (z)[0] = mpc_realref (op)[0]; + mpc_realref (tan_z)[0] = mpc_imagref (rop)[0]; + mpc_imagref (tan_z)[0] = mpc_realref (rop)[0]; + + inex = mpc_tan (tan_z, z, MPC_RND (MPC_RND_IM (rnd), MPC_RND_RE (rnd))); + + /* tan_z and rop parts share the same significands, copy the rest now. */ + mpc_realref (rop)[0] = mpc_imagref (tan_z)[0]; + mpc_imagref (rop)[0] = mpc_realref (tan_z)[0]; + + /* swap inexact flags for real and imaginary parts */ + return MPC_INEX (MPC_INEX_IM (inex), MPC_INEX_RE (inex)); +} |