public static function meanVar(array $values) : array
    {
        $mean = self::mean($values);

        return [$mean, self::variance($values, $mean)];
    }
public static function meanVar(array $values) : array
    {
        $mean = self::mean($values);

        return [$mean, self::variance($values, $mean)];
    }
public static function meanVar ( array $ values ) : array { $ mean = self :: mean ( $ values ) ; return [ $ mean , self :: variance ( $ values , $ mean ) ] ; }
Compute the population mean and variance and return them in a 2-tuple.

@param array $values
@return array
Compute the population mean and variance and return them in a 2 - tuple .