Phpml\Math\Statistic\Mean::arithmetic PHP Метод

    public static function arithmetic(array $numbers)
    {
        self::checkArrayLength($numbers);
        return array_sum($numbers) / count($numbers);
    }

 public function testArithmeticMean()
 {
     $delta = 0.01;
     $this->assertEquals(3.5, Mean::arithmetic([2, 5]), '', $delta);
     $this->assertEquals(41.16, Mean::arithmetic([43, 21, 25, 42, 57, 59]), '', $delta);
     $this->assertEquals(1.7, Mean::arithmetic([0.5, 0.5, 1.5, 2.5, 3.5]), '', $delta);
 }