log10, log10f, log10l - base 10 logarithm function

Syntax	#include <math.h> double log10(double x); C11 float log10f(float x); long double log10l(long double x); (End)
Description	These functions compute the logarithm of the positive floating-point number x to the base 10.
Return val.	lg(x)	for a positive x.
	-HUGE_VAL -HUGE_VALF -HUGE_VALL	depending on the function type, if x is less than or equal to 0. errno is set to indicate the error.
Errors	log10(), log10f() and log10l() will fail if:
	EDOM	The value of x is negative.
	ERANGE	The value of x is 0.
See also	exp(), exp2(), log(), log2(), pow(), sqrt(), math.h.