log10, log10f
[base 10 logarithms]

SYNOPSIS
#include <math.h> 
double log10(double x); 
float log10f(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 for “log, logf ” for information on errors.

COMPLIANCE
log10 is ANSI C. log10f is an extension.