phpOMS/Math/Statistic/Forecast/Forecasts.php

<?php
/**
 * Orange Management
 *
 * PHP Version 7.2
 *
 * @package    phpOMS\Math\Statistic\Forecast
 * @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\Statistic\Forecast;

/**
 * General forecasts helper class.
 *
 * @package    phpOMS\Math\Statistic\Forecast
 * @license    OMS License 1.0
 * @link       http://website.orange-management.de
 * @since      1.0.0
 */
class Forecasts
{
    /**
     * Get forecast/prediction interval.
     *
     * @param float $forecast          Forecast value
     * @param float $standardDeviation Standard Deviation of forecast
     * @param float $interval          Forecast multiplier for prediction intervals
     *
     * @return array<float|int>
     *
     * @since  1.0.0
     */
    public static function getForecastInteval(float $forecast, float $standardDeviation, float $interval = ForecastIntervalMultiplier::P_95) : array
    {
        return [$forecast - $interval * $standardDeviation, $forecast + $interval * $standardDeviation];
    }
}