public static function PHPExcel_Calculation_Statistical::COVAR in Loft Data Grids 7.2

Same name and namespace in other branches

1. 6.2 vendor/phpoffice/phpexcel/Classes/PHPExcel/Calculation/Statistical.php \PHPExcel_Calculation_Statistical::COVAR()

* COVAR * * Returns covariance, the average of the products of deviations for each data point pair. * *

Parameters

array of mixed Data Series Y: * @param array of mixed Data Series X * @return float

File

vendor/phpoffice/phpexcel/Classes/PHPExcel/Calculation/Statistical.php, line 1293

Class

PHPExcel_Calculation_Statistical

PHPExcel_Calculation_Statistical

Code

public static function COVAR($yValues, $xValues) {
  if (!self::_checkTrendArrays($yValues, $xValues)) {
    return PHPExcel_Calculation_Functions::VALUE();
  }
  $yValueCount = count($yValues);
  $xValueCount = count($xValues);
  if ($yValueCount == 0 || $yValueCount != $xValueCount) {
    return PHPExcel_Calculation_Functions::NA();
  }
  elseif ($yValueCount == 1) {
    return PHPExcel_Calculation_Functions::DIV0();
  }
  $bestFitLinear = trendClass::calculate(trendClass::TREND_LINEAR, $yValues, $xValues);
  return $bestFitLinear
    ->getCovariance();
}