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#include <sys/cdefs.h>
14#if defined(LIBM_SCCS) && !defined(lint)
15__RCSID("$NetBSD: w_atanh.c,v 1.8 1999/07/02 15:37:44 simonb Exp $");
16#endif
17
18/*
19 * wrapper atanh(x)
20 */
21
22#include "math.h"
23#include "math_private.h"
24
25
26double
27atanh(double x)		/* wrapper atanh */
28{
29#ifdef _IEEE_LIBM
30	return __ieee754_atanh(x);
31#else
32	double z,y;
33	z = __ieee754_atanh(x);
34	if(_LIB_VERSION == _IEEE_ || isnan(x)) return z;
35	y = fabs(x);
36	if(y>=1.0) {
37	    if(y>1.0)
38	        return __kernel_standard(x,x,30); /* atanh(|x|>1) */
39	    else
40	        return __kernel_standard(x,x,31); /* atanh(|x|==1) */
41	} else
42	    return z;
43#endif
44}
45