RTAI API: base/math/w_sqrt.c Source File

00001 /* @(#)w_sqrt.c 5.1 93/09/24 */
00002 /*
00003  * ====================================================
00004  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
00005  *
00006  * Developed at SunPro, a Sun Microsystems, Inc. business.
00007  * Permission to use, copy, modify, and distribute this
00008  * software is freely granted, provided that this notice 
00009  * is preserved.
00010  * ====================================================
00011  */
00012 
00013 #if defined(LIBM_SCCS) && !defined(lint)
00014 static char rcsid[] = "$NetBSD: w_sqrt.c,v 1.6 1995/05/10 20:49:55 jtc Exp $";
00015 #endif
00016 
00017 /* 
00018  * wrapper sqrt(x)
00019  */
00020 
00021 #include "math.h"
00022 #include "mathP.h"
00023 
00024 #ifdef __STDC__
00025     double sqrt(double x)       /* wrapper sqrt */
00026 #else
00027     double sqrt(x)          /* wrapper sqrt */
00028     double x;
00029 #endif
00030 {
00031 #ifdef _IEEE_LIBM
00032     return __ieee754_sqrt(x);
00033 #else
00034     double z;
00035     z = __ieee754_sqrt(x);
00036     if(_LIB_VERSION == _IEEE_ || isnan(x)) return z;
00037     if(x<0.0) {
00038         return __kernel_standard(x,x,26); /* sqrt(negative) */
00039     } else
00040         return z;
00041 #endif
00042 }