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/* @(#)z_log10.c 1.0 98/08/13 */
/******************************************************************
* Logarithm
*
* Input:
* x - floating point value
*
* Output:
* logarithm of x
*
* Description:
* This routine returns the logarithm of x (base 10).
*
*****************************************************************/
/*
FUNCTION
<<log10>>, <<log10f>>---base 10 logarithms
INDEX
log10
INDEX
log10f
ANSI_SYNOPSIS
#include <math.h>
double log10(double <[x]>);
float log10f(float <[x]>);
TRAD_SYNOPSIS
#include <math.h>
double log10(<[x]>)
double <[x]>;
float log10f(<[x]>)
float <[x]>;
DESCRIPTION
<<log10>> returns the base 10 logarithm of <[x]>.
It is implemented as <<log(<[x]>) / log(10)>>.
<<log10f>> is identical, save that it takes and returns <<float>> values.
RETURNS
<<log10>> and <<log10f>> return the calculated value.
See the description of <<log>> for information on errors.
PORTABILITY
<<log10>> is ANSI C. <<log10f>> is an extension.
*/
#include "fdlibm.h"
#include "zmath.h"
#ifndef _DOUBLE_IS_32BITS
double
_DEFUN (log10, (double),
double x)
{
return (logarithm (x, 1));
}
#endif /* _DOUBLE_IS_32BITS */
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