Phpml\Metric\ConfusionMatrix::compute PHP Method

    public static function compute(array $actualLabels, array $predictedLabels, array $labels = null) : array
    {
        $labels = $labels ? array_flip($labels) : self::getUniqueLabels($actualLabels);
        $matrix = self::generateMatrixWithZeros($labels);
        foreach ($actualLabels as $index => $actual) {
            $predicted = $predictedLabels[$index];
            if (!isset($labels[$actual]) || !isset($labels[$predicted])) {
                continue;
            }
            if ($predicted === $actual) {
                $row = $column = $labels[$actual];
            } else {
                $row = $labels[$actual];
                $column = $labels[$predicted];
            }
            $matrix[$row][$column] += 1;
        }
        return $matrix;
    }