<?php
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namespace PhpOffice\PhpSpreadsheet\Calculation\Statistical;
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use PhpOffice\PhpSpreadsheet\Calculation\ArrayEnabled;
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use PhpOffice\PhpSpreadsheet\Calculation\Exception;
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use PhpOffice\PhpSpreadsheet\Calculation\Information\ExcelError;
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class Standardize extends StatisticalValidations
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{
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use ArrayEnabled;
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/**
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* STANDARDIZE.
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*
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* Returns a normalized value from a distribution characterized by mean and standard_dev.
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*
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* @param array|float $value Value to normalize
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* Or can be an array of values
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* @param array|float $mean Mean Value
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* Or can be an array of values
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* @param array|float $stdDev Standard Deviation
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* Or can be an array of values
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*
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* @return array|float|string Standardized value, or a string containing an error
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* If an array of numbers is passed as an argument, then the returned result will also be an array
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* with the same dimensions
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*/
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public static function execute($value, $mean, $stdDev): array|string|float
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{
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if (is_array($value) || is_array($mean) || is_array($stdDev)) {
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return self::evaluateArrayArguments([self::class, __FUNCTION__], $value, $mean, $stdDev);
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}
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try {
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$value = self::validateFloat($value);
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$mean = self::validateFloat($mean);
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$stdDev = self::validateFloat($stdDev);
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} catch (Exception $e) {
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return $e->getMessage();
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}
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if ($stdDev <= 0) {
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return ExcelError::NAN();
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}
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return ($value - $mean) / $stdDev;
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}
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}
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