log
PHP function
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(PHP 4, PHP 5, PHP 7, PHP 8)
Natural logarithm
Description
log(float $num, float $base = M_E): float
If the optional base parameter is specified, log() returns logbase num, otherwise log() returns the natural logarithm of num.
Parameters
numThe value to calculate the logarithm for
baseThe optional logarithmic base to use (defaults to 'e' and so to the natural logarithm).
Return Values
The logarithm of num to base, if given, or the natural logarithm.