lchown: Avoid "unused variable" warning.

[gnulib.git] / lib / cosl.c

diff --git a/lib/cosl.c b/lib/cosl.c
index f019eee..884cec8 100644 (file)
--- a/lib/cosl.c
+++ b/lib/cosl.c
@@ -13,26 +13,31 @@
  * ====================================================
  */
 
+#include <config.h>
+
+/* Specification.  */
+#include <math.h>
+
 /* sinl(x)
  * Return sine function of x.
  *
  * kernel function:
- *     __kernel_sinl           ... sine function on [-pi/4,pi/4]
- *     __kernel_cosl           ... cose function on [-pi/4,pi/4]
- *     __ieee754_rem_pio2l     ... argument reduction routine
+ *      __kernel_sinl           ... sine function on [-pi/4,pi/4]
+ *      __kernel_cosl           ... cose function on [-pi/4,pi/4]
+ *      __ieee754_rem_pio2l     ... argument reduction routine
  *
  * Method.
  *      Let S,C and T denote the sin, cos and tan respectively on
- *     [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
- *     in [-pi/4 , +pi/4], and let n = k mod 4.
- *     We have
+ *      [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
+ *      in [-pi/4 , +pi/4], and let n = k mod 4.
+ *      We have
  *
  *          n        sin(x)      cos(x)        tan(x)
  *     ----------------------------------------------------------
- *         0          S           C             T
- *         1          C          -S            -1/T
- *         2         -S          -C             T
- *         3         -C           S            -1/T
+ *          0          S           C             T
+ *          1          C          -S            -1/T
+ *          2         -S          -C             T
+ *          3         -C           S            -1/T
  *     ----------------------------------------------------------
  *
  * Special cases:
@@ -41,49 +46,45 @@
  *      trig(NaN)    is that NaN;
  *
  * Accuracy:
- *     TRIG(x) returns trig(x) nearly rounded
+ *      TRIG(x) returns trig(x) nearly rounded
  */
 
-#include <math.h>
-
-#include "mathl.h"
-
 #include "trigl.h"
-#ifdef HAVE_SINL
-#include "trigl.c"
-#include "sincosl.c"
-#endif
 
 long double cosl(long double x)
 {
-       long double y[2],z=0.0L;
-       int n;
+        long double y[2],z=0.0L;
+        int n;
+
+    /* cosl(NaN) is NaN */
+        if (isnanl (x))
+          return x;
 
     /* |x| ~< pi/4 */
         if(x >= -0.7853981633974483096156608458198757210492 &&
            x <= 0.7853981633974483096156608458198757210492)
           return kernel_cosl(x, z);
 
-    /* sinl(Inf or NaN) is NaN, sinl(0) is 0 */
-        else if ((x + x == x && x != 0.0) || x != x)
+    /* cosl(Inf) is NaN, cosl(0) is 1 */
+        else if (x + x == x && x != 0.0)
           return x-x;           /* NaN */
 
     /* argument reduction needed */
-       else {
-           n = ieee754_rem_pio2l(x,y);
+        else {
+            n = ieee754_rem_pio2l(x,y);
             switch(n&3) {
                 case 0: return  kernel_cosl(y[0],y[1]);
                 case 1: return -kernel_sinl(y[0],y[1],1);
                 case 2: return -kernel_cosl(y[0],y[1]);
                 default:
                         return  kernel_sinl(y[0],y[1],1);
-           }
-       }
+            }
+        }
 }
 
 #if 0
 int
-main ()
+main (void)
 {
   printf ("%.16Lg\n", cosl(0.7853981633974483096156608458198757210492));
   printf ("%.16Lg\n", cosl(0.7853981633974483096156608458198757210492 *29));