prime/src/Runtime/w_atan2.c

41 lines
892 B
C

/* @(#)w_atan2.c 1.2 95/01/04 */
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*
*/
/*
* wrapper atan2(y,x)
*/
#include "fdlibm.h"
#ifdef __STDC__
double atan2(double y, double x) /* wrapper atan2 */
#else
double atan2(y, x) /* wrapper atan2 */
double y, x;
#endif
{
#ifdef _IEEE_LIBM
return __ieee754_atan2(y, x);
#else
double z;
z = __ieee754_atan2(y, x);
if (_LIB_VERSION == _IEEE_ || isnan(x) || isnan(y))
return z;
if (x == 0.0 && y == 0.0) {
return __kernel_standard(y, x, 3); /* atan2(+-0,+-0) */
} else
return z;
#endif
}