Returns the natural logarithm (base e) of EXPR. If EXPR is omitted, returns the log of $_
. To get the log of another base, use basic algebra: The base-N log of a number is equal to the natural log of that number divided by the natural log of N. For example:
sub log10 {
my $n = shift;
return log($n)/log(10);
}
See also exp
for the inverse operation.