windows-nt/Source/XPSP1/NT/base/crts/crtw32/stdcpp/xlcosh.c
2020-09-26 16:20:57 +08:00

41 lines
814 B
C

/* _LCosh function */
#include "xmath.h"
_STD_BEGIN
_CRTIMP2 long double __cdecl _LCosh(long double x, long double y)
{ /* compute y * cosh(x), |y| <= 1 */
switch (_LDtest(&x))
{ /* test for special codes */
case _NANCODE:
case _INFCODE:
return (x);
case 0:
return (y);
default: /* finite */
if (y == 0.0L)
return (y);
if (x < 0.0)
x = -x;
if (x < _LXbig)
{ /* worth adding in exp(-x) */
_LExp(&x, 1.0L, -1);
return (y * (x + 0.25L / x));
}
switch (_LExp(&x, y, -1))
{ /* report over/underflow */
case 0:
_Feraise(_FE_UNDERFLOW);
break;
case _INFCODE:
_Feraise(_FE_OVERFLOW);
}
return (x);
}
}
_STD_END
/*
* Copyright (c) 1992-2001 by P.J. Plauger. ALL RIGHTS RESERVED.
* Consult your license regarding permissions and restrictions.
V3.10:0009 */