public function pcmlToArray(\SimpleXMLElement $xmlObj)
    {
        $dataDescription = array();

        // put structs in its own variable that can be accessed independently.
        $this->_pcmlStructs = $xmlObj->xpath('struct');

        // looking for ->data and ->struct.
        $dataElements = $xmlObj->xpath('program/data');

        if ($dataElements) {
            foreach ($dataElements as $dataElement) {

                $dataDescription[] = $this->singlePcmlToArray($dataElement);
            }
        }

        return $dataDescription;
    }