Fatal error: Uncaught Error: Undefined constant "PHPEXCEL_ROOT" in C:\xampp\htdocs\crop_db\libs\phpoffice\PHPExcel\Shared\trend\logarithmicBestFitClass.php:29 Stack trace: #0 {main} thrown in C:\xampp\htdocs\crop_db\libs\phpoffice\PHPExcel\Shared\trend\logarithmicBestFitClass.php on line 29