StdLib/LibC/Math/w_atan2.c

   1 /* @(#)w_atan2.c 5.1 93/09/24 */
   2 /*
   3  * ====================================================
   4  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
   5  *
   6  * Developed at SunPro, a Sun Microsystems, Inc. business.
   7  * Permission to use, copy, modify, and distribute this
   8  * software is freely granted, provided that this notice
   9  * is preserved.
  10  * ====================================================
  11  */
  12 #include  <LibConfig.h>
  13 #include  <sys/EfiCdefs.h>
  14 #if defined(LIBM_SCCS) && !defined(lint)
  15 __RCSID("$NetBSD: w_atan2.c,v 1.9 2002/05/26 22:01:59 wiz Exp $");
  16 #endif
  17
  18 /*
  19  * wrapper atan2(y,x)
  20  */
  21
  22 #include "math.h"
  23 #include "math_private.h"
  24
  25
  26 double
  27 atan2(double y, double x) /* wrapper atan2 */
  28 {
  29 #ifdef _IEEE_LIBM
  30   return __ieee754_atan2(y,x);
  31 #else
  32   double z;
  33   z = __ieee754_atan2(y,x);
  34   if(_LIB_VERSION == _IEEE_||isnan(x)||isnan(y)) return z;
  35   if(x==0.0&&y==0.0) {
  36           return __kernel_standard(y,x,3); /* atan2(+-0,+-0) */
  37   } else
  38       return z;
  39 #endif
  40 }