phpOMS/tests/Algorithm/Clustering/KmeansTest.php

<?php
/**
 * Orange Management
 *
 * PHP Version 7.4
 *
 * @package   tests
 * @copyright Dennis Eichhorn
 * @license   OMS License 1.0
 * @version   1.0.0
 * @link      https://orange-management.org
 */
declare(strict_types=1);

namespace phpOMS\Algorithm\Clustering;

use phpOMS\Algorithm\Clustering\Kmeans;

/**
 * @testdox phpOMS\Algorithm\Clustering\Kmeans: Test the kmeans clustering implementation
 *
 * @internal
 */
class KmeansTest extends \PHPUnit\Framework\TestCase
{
    public function testKmeans() : void
    {
        $result = false;

        // due to the random nature this can be false sometimes?!
        for ($i = 0; $i < 10; ++$i) {
            $points = [
                new Point([1.0, 1.0], '1'),
                new Point([1.5, 2.0], '2'),
                new Point([3.0, 4.0], '3'),
                new Point([5.0, 7.0], '4'),
                new Point([3.5, 5.0], '5'),
                new Point([4.5, 5.0], '6'),
                new Point([3.5, 4.5], '7'),
            ];

            $kmeans = new Kmeans($points, 2);

            if ($kmeans->cluster($points[0])->getGroup() === 0
                && $kmeans->cluster($points[1])->getGroup() === 0
                && $kmeans->cluster($points[2])->getGroup() === 1
                && $kmeans->cluster($points[3])->getGroup() === 1
                && $kmeans->cluster($points[4])->getGroup() === 1
                && $kmeans->cluster($points[5])->getGroup() === 1
                && $kmeans->cluster($points[6])->getGroup() === 1
            ) {
                $result = true;

                break;
            }
        }

        self::assertTrue($result);
    }
}