/* _FSinh function */ #include "wctype.h" #include "xmath.h" _STD_BEGIN /* coefficients */ #define NP (sizeof (p) / sizeof (p[0]) - 1) static const float p[] = { /* courtesy Dr. Tim Prince */ 0.00020400F, 0.00832983F, 0.16666737F, 0.99999998F}; _CRTIMP2 float __cdecl _FSinh(float x, float y) { /* compute y*sinh(x), |y| <= 1 */ switch (_FDtest(&x)) { /* test for special codes */ case NAN: errno = EDOM; return (x); case INF: if (y == 0) return (0); errno = ERANGE; return (FSIGN(x) ? -_FInf._F : _FInf._F); case 0: return (0); default: /* finite */ { /* compute sinh(finite) */ short neg; if (x < 0) x = -x, neg = 1; else neg = 0; if (x < _FRteps._F) x *= y; /* x tiny */ else if (x < 1) { float w = x * x; x += ((p[0] * w + p[1]) * w + p[2]) * w * x; x *= y; } else if (x < _FXbig) { /* worth adding in exp(-x) */ _FExp(&x, 1, -1); x = y * (x - 0.25 / x); } else if (0 <= _FExp(&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 */