forked from KolibriOS/kolibrios
49 lines
946 B
C
49 lines
946 B
C
/* sf_log2.c -- float version of s_log2.c.
|
|
* Modification of sf_exp10.c by Yaakov Selkowitz 2009.
|
|
*/
|
|
|
|
/*
|
|
* ====================================================
|
|
* 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 log2f(x)
|
|
*/
|
|
|
|
#include "fdlibm.h"
|
|
#include <errno.h>
|
|
#include <math.h>
|
|
#undef log2
|
|
#undef log2f
|
|
|
|
#ifdef __STDC__
|
|
float log2f(float x) /* wrapper log2f */
|
|
#else
|
|
float log2f(x) /* wrapper log2f */
|
|
float x;
|
|
#endif
|
|
{
|
|
return (logf(x) / (float_t) M_LN2);
|
|
}
|
|
|
|
#ifdef _DOUBLE_IS_32BITS
|
|
|
|
#ifdef __STDC__
|
|
double log2(double x)
|
|
#else
|
|
double log2(x)
|
|
double x;
|
|
#endif
|
|
{
|
|
return (double) log2f((float) x);
|
|
}
|
|
|
|
#endif /* defined(_DOUBLE_IS_32BITS) */
|