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Differences Between: [Versions 400 and 401]

   1  <?php
   2  
   3  namespace PhpOffice\PhpSpreadsheet\Calculation\MathTrig;
   4  
   5  use PhpOffice\PhpSpreadsheet\Calculation\ArrayEnabled;
   6  use PhpOffice\PhpSpreadsheet\Calculation\Exception;
   7  use PhpOffice\PhpSpreadsheet\Calculation\Functions;
   8  
   9  class SeriesSum
  10  {
  11      use ArrayEnabled;
  12  
  13      /**
  14       * SERIESSUM.
  15       *
  16       * Returns the sum of a power series
  17       *
  18       * @param mixed $x Input value
  19       * @param mixed $n Initial power
  20       * @param mixed $m Step
  21       * @param mixed[] $args An array of coefficients for the Data Series
  22       *
  23       * @return array|float|string The result, or a string containing an error
  24       */
  25      public static function evaluate($x, $n, $m, ...$args)
  26      {
  27          if (is_array($x) || is_array($n) || is_array($m)) {
  28              return self::evaluateArrayArgumentsSubset([self::class, __FUNCTION__], 3, $x, $n, $m, ...$args);
  29          }
  30  
  31          try {
  32              $x = Helpers::validateNumericNullSubstitution($x, 0);
  33              $n = Helpers::validateNumericNullSubstitution($n, 0);
  34              $m = Helpers::validateNumericNullSubstitution($m, 0);
  35  
  36              // Loop through arguments
  37              $aArgs = Functions::flattenArray($args);
  38              $returnValue = 0;
  39              $i = 0;
  40              foreach ($aArgs as $argx) {
  41                  if ($argx !== null) {
  42                      $arg = Helpers::validateNumericNullSubstitution($argx, 0);
  43                      $returnValue += $arg * $x ** ($n + ($m * $i));
  44                      ++$i;
  45                  }
  46              }
  47          } catch (Exception $e) {
  48              return $e->getMessage();
  49          }
  50  
  51          return $returnValue;
  52      }
  53  }