POK
/home/jaouen/pok_official/pok/trunk/libpok/libm/sqrtf.c
00001 /*
00002  *                               POK header
00003  * 
00004  * The following file is a part of the POK project. Any modification should
00005  * made according to the POK licence. You CANNOT use this file or a part of
00006  * this file is this part of a file for your own project
00007  *
00008  * For more information on the POK licence, please see our LICENCE FILE
00009  *
00010  * Please follow the coding guidelines described in doc/CODING_GUIDELINES
00011  *
00012  *                                      Copyright (c) 2007-2009 POK team 
00013  *
00014  * Created by julien on Fri Jan 30 14:41:34 2009 
00015  */
00016 
00017 /* w_sqrtf.c -- float version of w_sqrt.c.
00018  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
00019  */
00020 
00021 /*
00022  * ====================================================
00023  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
00024  *
00025  * Developed at SunPro, a Sun Microsystems, Inc. business.
00026  * Permission to use, copy, modify, and distribute this
00027  * software is freely granted, provided that this notice
00028  * is preserved.
00029  * ====================================================
00030  */
00031 
00032 #ifdef POK_NEEDS_LIBMATH
00033 
00034 /*
00035  * wrapper sqrtf(x)
00036  */
00037 
00038 #include "math_private.h"
00039 #include <libm.h>
00040 
00041 float
00042 sqrtf(float x)          /* wrapper sqrtf */
00043 {
00044 #ifdef _IEEE_LIBM
00045         return __ieee754_sqrtf(x);
00046 #else
00047         float z;
00048         z = __ieee754_sqrtf(x);
00049         if (isnanf(x)) return z;
00050         if(x<(float)0.0) {
00051             /* sqrtf(negative) */
00052             return (float)-1.0;
00053         } else
00054             return z;
00055 #endif
00056 }
00057 
00058 #endif