source: trunk/sys/libm/w_atanh.c @ 50

/* @(#)w_atanh.c 5.1 93/09/24 */
/*
 * ====================================================
 * 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 atanh(x)
 */

#include <libm/fdlibm.h>


#ifdef __STDC__
        double atanh(double x)          /* wrapper atanh */
#else
        double atanh(x)                 /* wrapper atanh */
        double x;
#endif
{
#ifdef _IEEE_LIBM
        return __ieee754_atanh(x);
#else
        double z,y;
        z = __ieee754_atanh(x);
        if(_LIB_VERSION == _IEEE_ || isnan(x)) return z;
        y = fabs(x);
        if(y>=1.0) {
            if(y>1.0)
                return __kernel_standard(x,x,30); /* atanh(|x|>1) */
            else 
                return __kernel_standard(x,x,31); /* atanh(|x|==1) */
        } else
            return z;
#endif
}