Gpf_Data_Record::set PHP Method

        public function set($id, $value)
        {
            $index = $this->header->getIndex($id);
            $this->record[$index] = $value;
        }

 private function fillResultRecord(Gpf_Data_Record $record, Gpf_Data_Record $row) {
     foreach ($this->dataColumns as $columnId => $column) {
         try {
             $record->set($columnId, $row->get($column->getName()));
         } catch (Gpf_Exception $e) {
             $record->set($columnId, '');
         }
     }
     return $record;
 }