*
*/
-/* Copyright 2001 by Stephen L. Moshier <moshier@na-net.ornl.gov> */
+/* Copyright 2001 by Stephen L. Moshier <moshier@na-net.ornl.gov>
+
+ 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,
+ 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include "mathl.h"
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;
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;
}