log — Calculates the natural logarithm of a number.
float num: Value from which
to get natural logarithm
Natural logarithm of a number
Calculates the natural logarithm of the number given by
num . log() is the
opposite of the exp()
Example 677. Calculate the
natural logarithm of a number
$num = 54.5981;
echo "The natural log of $num is ",log($num),"\n";
PHP Functions Essential Reference. Copyright © 2002 by New Riders Publishing
(Authors: Zak Greant, Graeme Merrall, Torben Wilson, Brett Michlitsch).
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