use Population;

class DistributionPopulation is Population
{
        method BUILD() {

        }

        method Expectance() {

                my $e = 0.0;

                for .population -> $p {
                        $e += $p;
                }

                return $e / .population.length;
        }

        method Variance () {
                my $e = .Expectance();
                my $var = 0.0;

                for .population -> $p {
                        $var += ($p - $e) * ($p - $e);
                }

                return $var / (.population.length - 1);
        }


}