Perl 5 version 32.0 documentation


  • log EXPR

  • log

    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:

    1. sub log10 {
    2. my $n = shift;
    3. return log($n)/log(10);
    4. }

    See also exp for the inverse operation.