<?php

namespace TablePress\PhpOffice\PhpSpreadsheet\Calculation\Statistical;

class StandardDeviations
{
	/**
	 * STDEV.
	 *
	 * Estimates standard deviation based on a sample. The standard deviation is a measure of how
	 *        widely values are dispersed from the average value (the mean).
	 *
	 * Excel Function:
	 *        STDEV(value1[,value2[, ...]])
	 *
	 * @param mixed ...$args Data values
	 *
	 * @return float|string The result, or a string containing an error
	 */
	public static function STDEV(...$args)
	{
		$result = Variances::VAR(...$args);
		if (!is_numeric($result)) {
			return $result;
		}

		return sqrt((float) $result);
	}

	/**
	 * STDEVA.
	 *
	 * Estimates standard deviation based on a sample, including numbers, text, and logical values
	 *
	 * Excel Function:
	 *        STDEVA(value1[,value2[, ...]])
	 *
	 * @param mixed ...$args Data values
	 *
	 * @return float|string
	 */
	public static function STDEVA(...$args)
	{
		$result = Variances::VARA(...$args);
		if (!is_numeric($result)) {
			return $result;
		}

		return sqrt((float) $result);
	}

	/**
	 * STDEVP.
	 *
	 * Calculates standard deviation based on the entire population
	 *
	 * Excel Function:
	 *        STDEVP(value1[,value2[, ...]])
	 *
	 * @param mixed ...$args Data values
	 *
	 * @return float|string
	 */
	public static function STDEVP(...$args)
	{
		$result = Variances::VARP(...$args);
		if (!is_numeric($result)) {
			return $result;
		}

		return sqrt((float) $result);
	}

	/**
	 * STDEVPA.
	 *
	 * Calculates standard deviation based on the entire population, including numbers, text, and logical values
	 *
	 * Excel Function:
	 *        STDEVPA(value1[,value2[, ...]])
	 *
	 * @param mixed ...$args Data values
	 *
	 * @return float|string
	 */
	public static function STDEVPA(...$args)
	{
		$result = Variances::VARPA(...$args);
		if (!is_numeric($result)) {
			return $result;
		}

		return sqrt((float) $result);
	}
}
