/* _Sinh function */ #include "wctype.h" #include "xmath.h" _STD_BEGIN /* coefficients */ #define NP (sizeof (p) / sizeof (p[0]) - 1) static const double p[] = { /* courtesy Dr. Tim Prince */ 0.0000000001632881, 0.0000000250483893, 0.0000027557344615, 0.0001984126975233, 0.0083333333334816, 0.1666666666666574, 1.0000000000000001}; _CRTIMP2 double __cdecl _Sinh(double x, double y) { /* compute y*sinh(x), |y| <= 1 */ switch (_Dtest(&x)) { /* test for special codes */ case NAN: errno = EDOM; return (x); case INF: if (y == 0) return (0); errno = ERANGE; return (DSIGN(x) ? -_Inf._D : _Inf._D); case 0: return (0); default: /* finite */ { /* compute sinh(finite) */ short neg; if (x < 0) x = -x, neg = 1; else neg = 0; if (x < _Rteps._D) x *= y; /* x tiny */ else if (x < 1) { double w = x * x; x += x * w * _Poly(w, p, NP - 1); x *= y; } else if (x < _Xbig) { /* worth adding in exp(-x) */ _Exp(&x, 1, -1); x = y * (x - 0.25 / x); } else if (0 <= _Exp(&x, y, -1)) errno = ERANGE; /* x large */ return (neg ? -x : x); } } } _STD_END /* * Copyright (c) 1994 by P.J. Plauger. ALL RIGHTS RESERVED. * Consult your license regarding permissions and restrictions. */ /* 941029 pjp: added _STD machinery */