diff options
Diffstat (limited to 'libm/e_cosh.c')
| -rw-r--r-- | libm/e_cosh.c | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/libm/e_cosh.c b/libm/e_cosh.c index 5d73fb5c4..88499684a 100644 --- a/libm/e_cosh.c +++ b/libm/e_cosh.c @@ -5,7 +5,7 @@ * * Developed at SunPro, a Sun Microsystems, Inc. business. * Permission to use, copy, modify, and distribute this - * software is freely granted, provided that this notice + * software is freely granted, provided that this notice * is preserved. * ==================================================== */ @@ -15,18 +15,18 @@ static char rcsid[] = "$NetBSD: e_cosh.c,v 1.7 1995/05/10 20:44:58 jtc Exp $"; #endif /* __ieee754_cosh(x) - * Method : + * Method : * mathematically cosh(x) if defined to be (exp(x)+exp(-x))/2 - * 1. Replace x by |x| (cosh(x) = cosh(-x)). - * 2. - * [ exp(x) - 1 ]^2 + * 1. Replace x by |x| (cosh(x) = cosh(-x)). + * 2. + * [ exp(x) - 1 ]^2 * 0 <= x <= ln2/2 : cosh(x) := 1 + ------------------- * 2*exp(x) * * exp(x) + 1/exp(x) * ln2/2 <= x <= 22 : cosh(x) := ------------------- * 2 - * 22 <= x <= lnovft : cosh(x) := exp(x)/2 + * 22 <= x <= lnovft : cosh(x) := exp(x)/2 * lnovft <= x <= ln2ovft: cosh(x) := exp(x/2)/2 * exp(x/2) * ln2ovft < x : cosh(x) := huge*huge (overflow) * @@ -50,7 +50,7 @@ static double one = 1.0, half=0.5, huge = 1.0e300; double __ieee754_cosh(x) double x; #endif -{ +{ double t,w; int32_t ix; u_int32_t lx; @@ -60,7 +60,7 @@ static double one = 1.0, half=0.5, huge = 1.0e300; ix &= 0x7fffffff; /* x is INF or NaN */ - if(ix>=0x7ff00000) return x*x; + if(ix>=0x7ff00000) return x*x; /* |x| in [0,0.5*ln2], return 1+expm1(|x|)^2/(2*exp(|x|)) */ if(ix<0x3fd62e43) { @@ -81,7 +81,7 @@ static double one = 1.0, half=0.5, huge = 1.0e300; /* |x| in [log(maxdouble), overflowthresold] */ GET_LOW_WORD(lx,x); - if (ix<0x408633CE || + if (ix<0x408633CE || ((ix==0x408633ce)&&(lx<=(u_int32_t)0x8fb9f87d))) { w = __ieee754_exp(half*fabs(x)); t = half*w; |