#include "libm.h"
-static const double one = 1.0, half = 0.5, huge = 1.0e300;
+static const double huge = 1.0e300;
double cosh(double x)
{
/* |x| in [0,0.5*ln2], return 1+expm1(|x|)^2/(2*exp(|x|)) */
if (ix < 0x3fd62e43) {
t = expm1(fabs(x));
- w = one+t;
+ w = 1.0+t;
if (ix < 0x3c800000)
return w; /* cosh(tiny) = 1 */
- return one + (t*t)/(w+w);
+ return 1.0 + (t*t)/(w+w);
}
/* |x| in [0.5*ln2,22], return (exp(|x|)+1/exp(|x|))/2; */
if (ix < 0x40360000) {
t = exp(fabs(x));
- return half*t + half/t;
+ return 0.5*t + 0.5/t;
}
- /* |x| in [22, log(maxdouble)] return half*exp(|x|) */
+ /* |x| in [22, log(maxdouble)] return 0.5*exp(|x|) */
if (ix < 0x40862E42)
- return half*exp(fabs(x));
+ return 0.5*exp(fabs(x));
/* |x| in [log(maxdouble), overflowthresold] */
if (ix <= 0x408633CE)