log10 — Calculates the base 10 logarithm of a number.
float num: Number from which
to derive the base 10 logarithm
Base 10 logarithm of a number
log10() returns the base 10 logarithm of the
number given by num .
Example 678. Calculate the
base 10 logarithm
echo "The base 10 logarithm of 10 is ", log10(10);
PHP Functions Essential Reference. Copyright © 2002 by New Riders Publishing
(Authors: Zak Greant, Graeme Merrall, Torben Wilson, Brett Michlitsch).
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