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Differences Between: [Versions 400 and 402] [Versions 401 and 402]

   1  <?php
   2  
   3  namespace PhpOffice\PhpSpreadsheet\Calculation\Database;
   4  
   5  use PhpOffice\PhpSpreadsheet\Calculation\Information\ExcelError;
   6  use PhpOffice\PhpSpreadsheet\Calculation\Statistical\StandardDeviations;
   7  
   8  class DStDev extends DatabaseAbstract
   9  {
  10      /**
  11       * DSTDEV.
  12       *
  13       * Estimates the standard deviation of a population based on a sample by using the numbers in a
  14       * column of a list or database that match conditions that you specify.
  15       *
  16       * Excel Function:
  17       *        DSTDEV(database,field,criteria)
  18       *
  19       * @param mixed[] $database The range of cells that makes up the list or database.
  20       *                                        A database is a list of related data in which rows of related
  21       *                                        information are records, and columns of data are fields. The
  22       *                                        first row of the list contains labels for each column.
  23       * @param int|string $field Indicates which column is used in the function. Enter the
  24       *                                        column label enclosed between double quotation marks, such as
  25       *                                        "Age" or "Yield," or a number (without quotation marks) that
  26       *                                        represents the position of the column within the list: 1 for
  27       *                                        the first column, 2 for the second column, and so on.
  28       * @param mixed[] $criteria The range of cells that contains the conditions you specify.
  29       *                                        You can use any range for the criteria argument, as long as it
  30       *                                        includes at least one column label and at least one cell below
  31       *                                        the column label in which you specify a condition for the
  32       *                                        column.
  33       *
  34       * @return float|string
  35       */
  36      public static function evaluate($database, $field, $criteria)
  37      {
  38          $field = self::fieldExtract($database, $field);
  39          if ($field === null) {
  40              return ExcelError::VALUE();
  41          }
  42  
  43          return StandardDeviations::STDEV(
  44              self::getFilteredColumn($database, $field, $criteria)
  45          );
  46      }
  47  }