compiler/mlib/w_atanh.c

   1 /* @(#)w_atanh.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
  13 #ifndef lint
  14 static char rcsid[] = "$FreeBSD: src/lib/msun/src/w_atanh.c,v 1.5 1999/08/28 00:06:59 peter Exp $";
  15 #endif
  16
  17 /*
  18  * wrapper atanh(x)
  19  */
  20
  21 #include "math.h"
  22 #include "math_private.h"
  23
  24
  25 double
  26 atanh(double x)         /* wrapper atanh */
  27 {
  28 #ifdef _IEEE_LIBM
  29         return __ieee754_atanh(x);
  30 #else
  31         double z,y;
  32         z = __ieee754_atanh(x);
  33         if(_LIB_VERSION == _IEEE_ || isnan(x)) return z;
  34         y = fabs(x);
  35         if(y>=1.0) {
  36             if(y>1.0)
  37                 return __kernel_standard(x,x,30); /* atanh(|x|>1) */
  38             else
  39                 return __kernel_standard(x,x,31); /* atanh(|x|==1) */
  40         } else
  41             return z;
  42 #endif
  43 }