1 2 /* @(#)w_atanh.c 1.3 95/01/18 */ 3 /* 4 * ==================================================== 5 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 6 * 7 * Developed at SunSoft, a Sun Microsystems, Inc. business. 8 * Permission to use, copy, modify, and distribute this 9 * software is freely granted, provided that this notice 10 * is preserved. 11 * ==================================================== 12 */ 13 /* 14 * wrapper atanh(x) 15 */ 16 17 #include "fdlibm.h" 18 19 20 #ifdef __STDC__ atanh(double x)21 double atanh(double x) /* wrapper atanh */ 22 #else 23 double atanh(x) /* wrapper atanh */ 24 double x; 25 #endif 26 { 27 #ifdef _IEEE_LIBM 28 return __ieee754_atanh(x); 29 #else 30 double z,y; 31 z = __ieee754_atanh(x); 32 if(_LIB_VERSION == _IEEE_ || ieee_isnan(x)) return z; 33 y = ieee_fabs(x); 34 if(y>=1.0) { 35 if(y>1.0) 36 return __kernel_standard(x,x,30); /* atanh(|x|>1) */ 37 else 38 return __kernel_standard(x,x,31); /* atanh(|x|==1) */ 39 } else 40 return z; 41 #endif 42 } 43