PHP log10() Function

The PHP log10() function returns the base-10 logarithm of a given number. In special cases it returns the following:

• If the argument is NAN or less than zero, then the result is NAN.
• If the argument is positive infinity, then the result is positive infinity.
• If the argument is zero, then the result is negative infinity.

Syntax

log10(number)

Parameters

Return Value

Returns the base-10 logarithm of a given number.

Example:

In the example below, log10() function is used to calculate the base-10 logarithm of a given number.

<?php
echo "log10(0) = ".log10(0)."\n";
echo "log10(0.5) = ".log10(0.5)."\n";
echo "log10(1) = ".log10(1)."\n";
echo "log10(10) = ".log10(10)."\n";
echo "log10(100) = ".log10(100)."\n";
echo "log10(INF) = ".log10(INF)."\n";
echo "log10(-INF) = ".log10(-INF)."\n";
echo "log10(NAN) = ".log10(NAN)."\n";
?>

The output of the above code will be:

log10(0) = -INF
log10(0.5) = -0.30102999566398
log10(1) = 0
log10(10) = 1
log10(100) = 2
log10(INF) = INF
log10(-INF) = NAN
log10(NAN) = NAN