X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fatanl.c;h=07b8f6a59300ea82ff6a5f61cf1417d5e14e271f;hb=35a32ee9550d22a932f1a71d89653e351405638d;hp=2959e0bb5cf83a44d2c862cf1c45074c5f592cc4;hpb=5657b2536d242966c41c268b9ab4fe8df727bb13;p=gnulib.git diff --git a/lib/atanl.c b/lib/atanl.c index 2959e0bb5..07b8f6a59 100644 --- a/lib/atanl.c +++ b/lib/atanl.c @@ -42,7 +42,22 @@ * */ -/* Copyright 2001 by Stephen L. Moshier */ +/* Copyright 2001 by Stephen L. Moshier + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; see the file COPYING. + If not, write to the Free Software Foundation, + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include "mathl.h" @@ -161,19 +176,25 @@ atanl (long double x) int k, sign; long double t, u, p, q; - sign = (x < 0) ? -1 : 1; + sign = x < 0.0; /* Check for zero or NaN. */ if (x != x || x == 0.0) return x + x; - /* Check for infinity. */ if (x + x == x) - return sign * atantbl[83]; + { + /* Infinity. */ + if (sign) + return -atantbl[83]; + else + return atantbl[83]; + } - x *= sign; + if (sign) + x = -x; - if (x >= 10.25) /* 10.25 */ + if (x >= 10.25) { k = 83; t = -1.0/x; @@ -196,5 +217,9 @@ atanl (long double x) u = t * u * p / q + t; /* arctan x = arctan u + arctan t */ - return sign * (atantbl[k] + u); + u = atantbl[k] + u; + if (sign) + return (-u); + else + return u; }