|float|string If an array of numbers is passed as an argument, then the returned result will also be an array * with the same dimensions */ public static function distribution($sampleSuccesses, $sampleNumber, $populationSuccesses, $populationNumber) { if ( is_array($sampleSuccesses) || is_array($sampleNumber) || is_array($populationSuccesses) || is_array($populationNumber) ) { return self::evaluateArrayArguments( [self::class, __FUNCTION__], $sampleSuccesses, $sampleNumber, $populationSuccesses, $populationNumber ); } try { $sampleSuccesses = DistributionValidations::validateInt($sampleSuccesses); $sampleNumber = DistributionValidations::validateInt($sampleNumber); $populationSuccesses = DistributionValidations::validateInt($populationSuccesses); $populationNumber = DistributionValidations::validateInt($populationNumber); } catch (Exception $e) { return $e->getMessage(); } if (($sampleSuccesses < 0) || ($sampleSuccesses > $sampleNumber) || ($sampleSuccesses > $populationSuccesses)) { return ExcelError::NAN(); } if (($sampleNumber <= 0) || ($sampleNumber > $populationNumber)) { return ExcelError::NAN(); } if (($populationSuccesses <= 0) || ($populationSuccesses > $populationNumber)) { return ExcelError::NAN(); } $successesPopulationAndSample = (float) Combinations::withoutRepetition($populationSuccesses, $sampleSuccesses); $numbersPopulationAndSample = (float) Combinations::withoutRepetition($populationNumber, $sampleNumber); $adjustedPopulationAndSample = (float) Combinations::withoutRepetition( $populationNumber - $populationSuccesses, $sampleNumber - $sampleSuccesses ); return $successesPopulationAndSample * $adjustedPopulationAndSample / $numbersPopulationAndSample; } }