phpOMS/Math/Stochastic/NaiveBayesFilter.php

<?php
/**
 * Orange Management
 *
 * PHP Version 7.2
 *
 * @package    phpOMS\Math\Stochastic
 * @copyright  Dennis Eichhorn
 * @license    OMS License 1.0
 * @version    1.0.0
 * @link       http://website.orange-management.de
 */
declare(strict_types=1);
namespace phpOMS\Math\Stochastic;

/**
 * Bernulli distribution.
 *
 * @package    phpOMS\Math\Stochastic
 * @license    OMS License 1.0
 * @link       http://website.orange-management.de
 * @since      1.0.0
 */
class NaiveBayesFilter
{
    private $dict = [];

    public function __construct()
    {
    }

    public function trainMatch($matched) : void
    {
    }

    public function trainMismatch($mismatch) : void
    {
    }

    public function match($toMatch) : float
    {
        $normalizedDict = $this->normalizeDictionary();

        $n = 0.0;
        foreach ($toMatch as $element) {
            if (isset($normalizedDict[$element])) {
                $n += \log(1 - $normalizedDict[$element]['match'] / $normalizedDict[$element]['total']) - \log($normalizedDict[$element]['match'] / $normalizedDict[$element]['total']);
            }
        }

        return 1 / (1 + \exp($n));
    }

    private function normalizeDictionary() : array
    {
        return $this->dict;
    }
}