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Differences Between: [Versions 400 and 401]

   1  <?php
   2  
   3  namespace PhpOffice\PhpSpreadsheet\Calculation\Statistical;
   4  
   5  use PhpOffice\PhpSpreadsheet\Calculation\ArrayEnabled;
   6  use PhpOffice\PhpSpreadsheet\Calculation\Exception;
   7  use PhpOffice\PhpSpreadsheet\Calculation\Information\ExcelError;
   8  
   9  class Standardize extends StatisticalValidations
  10  {
  11      use ArrayEnabled;
  12  
  13      /**
  14       * STANDARDIZE.
  15       *
  16       * Returns a normalized value from a distribution characterized by mean and standard_dev.
  17       *
  18       * @param array|float $value Value to normalize
  19       *                      Or can be an array of values
  20       * @param array|float $mean Mean Value
  21       *                      Or can be an array of values
  22       * @param array|float $stdDev Standard Deviation
  23       *                      Or can be an array of values
  24       *
  25       * @return array|float|string Standardized value, or a string containing an error
  26       *         If an array of numbers is passed as an argument, then the returned result will also be an array
  27       *            with the same dimensions
  28       */
  29      public static function execute($value, $mean, $stdDev)
  30      {
  31          if (is_array($value) || is_array($mean) || is_array($stdDev)) {
  32              return self::evaluateArrayArguments([self::class, __FUNCTION__], $value, $mean, $stdDev);
  33          }
  34  
  35          try {
  36              $value = self::validateFloat($value);
  37              $mean = self::validateFloat($mean);
  38              $stdDev = self::validateFloat($stdDev);
  39          } catch (Exception $e) {
  40              return $e->getMessage();
  41          }
  42  
  43          if ($stdDev <= 0) {
  44              return ExcelError::NAN();
  45          }
  46  
  47          return ($value - $mean) / $stdDev;
  48      }
  49  }