php-ml/tests/Phpml/Math/Statistic/StandardDeviationTest.php
2016-04-27 23:28:01 +02:00

43 lines
1.3 KiB
PHP

<?php
declare (strict_types = 1);
namespace test\Phpml\Math\StandardDeviation;
use Phpml\Math\Statistic\StandardDeviation;
class StandardDeviationTest extends \PHPUnit_Framework_TestCase
{
public function testStandardDeviationOfPopulationSample()
{
//https://pl.wikipedia.org/wiki/Odchylenie_standardowe
$delta = 0.001;
$population = [5, 6, 8, 9];
$this->assertEquals(1.825, StandardDeviation::population($population), '', $delta);
//http://www.stat.wmich.edu/s216/book/node126.html
$delta = 0.5;
$population = [7100, 15500, 4400, 4400, 5900, 4600, 8800, 2000, 2750, 2550, 960, 1025];
$this->assertEquals(4079, StandardDeviation::population($population), '', $delta);
$population = [9300, 10565, 15000, 15000, 17764, 57000, 65940, 73676, 77006, 93739, 146088, 153260];
$this->assertEquals(50989, StandardDeviation::population($population), '', $delta);
}
/**
* @expectedException \Phpml\Exception\InvalidArgumentException
*/
public function testThrowExceptionOnEmptyArrayIfNotSample()
{
StandardDeviation::population([], false);
}
/**
* @expectedException \Phpml\Exception\InvalidArgumentException
*/
public function testThrowExceptionOnToSmallArray()
{
StandardDeviation::population([1]);
}
}