PHP log10() Function – Base‑10 Logarithm

The log10() function in PHP returns the base‑10 logarithm of a given floating‑point argument.

Signature: float log10(float $arg) Parameter: $arg – the number to calculate the logarithm for.

Return value: The base‑10 logarithm of $arg as a float.

Example:

<?php
echo log10(2.7183);
echo log10(2);
echo log10(1);
echo log10(0);
echo log10(-1);
?>

Output:

0.434297385125
0.301029995664
0
-INF
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