/** * @covers NumbersPHP\Statistic::covariance */ public function testCovariance() { $this->assertTrue(\NumbersPHP\Basic::numbersEqual(\NumbersPHP\Statistic::covariance(array(-5, -4, -1, 0, 5, 100), array(-6, 5, 2, 5, 2, 6)), 66.05555555555556, \NumbersPHP\Numbers::EPSILON)); }