double cosh(double x) { double t, w; int32_t ix; GET_HIGH_WORD(ix, x); ix &= 0x7fffffff; /* x is INF or NaN */ if (ix >= 0x7ff00000) return x*x; /* |x| in [0,0.5*ln2], return 1+expm1(|x|)^2/(2*exp(|x|)) */ if (ix < 0x3fd62e43) { t = expm1(fabs(x)); w = 1.0+t; if (ix < 0x3c800000) return w; /* cosh(tiny) = 1 */ 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 0.5*t + 0.5/t; } /* |x| in [22, log(maxdouble)] return 0.5*exp(|x|) */ if (ix < 0x40862E42) return 0.5*exp(fabs(x)); /* |x| in [log(maxdouble), overflowthresold] */ if (ix <= 0x408633CE) return __expo2(fabs(x)); /* |x| > overflowthresold, cosh(x) overflow */ return huge*huge; }
double sinh(double x) { double t, h; int32_t ix, jx; /* High word of |x|. */ GET_HIGH_WORD(jx, x); ix = jx & 0x7fffffff; /* x is INF or NaN */ if (ix >= 0x7ff00000) return x + x; h = 0.5; if (jx < 0) h = -h; /* |x| in [0,22], return sign(x)*0.5*(E+E/(E+1))) */ if (ix < 0x40360000) { /* |x|<22 */ if (ix < 0x3e300000) /* |x|<2**-28 */ /* raise inexact, return x */ if (huge+x > 1.0) return x; t = expm1(fabs(x)); if (ix < 0x3ff00000) return h*(2.0*t - t*t/(t+1.0)); return h*(t + t/(t+1.0)); } /* |x| in [22, log(maxdouble)] return 0.5*exp(|x|) */ if (ix < 0x40862E42) return h*exp(fabs(x)); /* |x| in [log(maxdouble), overflowthresold] */ if (ix <= 0x408633CE) return h * 2.0 * __expo2(fabs(x)); /* h is for sign only */ /* |x| > overflowthresold, sinh(x) overflow */ return x*huge; }