php-ml/tests/Phpml/Clustering/KMeansTest.php

<?php

declare (strict_types = 1);

namespace tests\Clustering;

use Phpml\Clustering\KMeans;

class KMeansTest extends \PHPUnit_Framework_TestCase
{
    public function testKMeansSamplesClustering()
    {
        $samples = [[1, 1], [8, 7], [1, 2], [7, 8], [2, 1], [8, 9]];

        $kmeans = new KMeans(2);
        $clusters = $kmeans->cluster($samples);

        $this->assertEquals(2, count($clusters));

        foreach ($samples as $index => $sample) {
            if (in_array($sample, $clusters[0]) || in_array($sample, $clusters[1])) {
                unset($samples[$index]);
            }
        }
        $this->assertEquals(0, count($samples));
    }

    public function testKMeansMoreSamplesClustering()
    {
        $samples = [
            [80, 55], [86, 59], [19, 85], [41, 47], [57, 58],
            [76, 22], [94, 60], [13, 93], [90, 48], [52, 54],
            [62, 46], [88, 44], [85, 24], [63, 14], [51, 40],
            [75, 31], [86, 62], [81, 95], [47, 22], [43, 95],
            [71, 19], [17, 65], [69, 21], [59, 60], [59, 12],
            [15, 22], [49, 93], [56, 35], [18, 20], [39, 59],
            [50, 15], [81, 36], [67, 62], [32, 15], [75, 65],
            [10, 47], [75, 18], [13, 45], [30, 62], [95, 79],
            [64, 11], [92, 14], [94, 49], [39, 13], [60, 68],
            [62, 10], [74, 44], [37, 42], [97, 60], [47, 73],
        ];

        $kmeans = new KMeans(4);
        $clusters = $kmeans->cluster($samples);

        $this->assertEquals(4, count($clusters));

        foreach ($samples as $index => $sample) {
            for ($i = 0; $i < 4; ++$i) {
                if (in_array($sample, $clusters[$i])) {
                    unset($samples[$index]);
                }
            }
        }
        $this->assertEquals(0, count($samples));
    }
}