Natural logarithm
Syntax
log ( float $arg [, float $base = M_E ] ) : float
Parameters
argThe value to calculate the logarithm for
baseThe optional logarithmic base to use (defaults to 'e' and so to the natural logarithm).
Return
The logarithm of arg to base, if given, or the natural logarithm.
Examples
1 · arg
<? $arg = 12.34; $return = log($arg); echo $return; ?>
2.5128460184772
2 · base
<? $arg = 12.34; $base = 2; $return = log($arg, $base); echo $return; ?>
3.6252704893747
