Vendor/phpspreadsheet/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Calculation/Statistical.php
public static function STANDARDIZE($value, $mean, $stdDev)
    {
        $value = Functions::flattenSingleValue($value);
        $mean = Functions::flattenSingleValue($mean);
        $stdDev = Functions::flattenSingleValue($stdDev);

        if ((is_numeric($value)) && (is_numeric($mean)) && (is_numeric($stdDev))) {
            if ($stdDev <= 0) {
                return Functions::NAN();
            }

            return ($value - $mean) / $stdDev;
        }

        return Functions::VALUE();
    }
public static function STANDARDIZE($value, $mean, $stdDev)
    {
        $value = Functions::flattenSingleValue($value);
        $mean = Functions::flattenSingleValue($mean);
        $stdDev = Functions::flattenSingleValue($stdDev);

        if ((is_numeric($value)) && (is_numeric($mean)) && (is_numeric($stdDev))) {
            if ($stdDev <= 0) {
                return Functions::NAN();
            }

            return ($value - $mean) / $stdDev;
        }

        return Functions::VALUE();
    }
STANDARDIZE.

Returns a normalized value from a distribution characterized by mean and standard_dev.

@param float $value Value to normalize
@param float $mean Mean Value
@param float $stdDev Standard Deviation

@return float Standardized value