In Codeigniter view file dataStore undefined error showing up

Controller

	public function get_payment_type_by_date($type = NULL)
    {				
				$report = new Payment(array(
				"dbname" => $this->dbname,
				"from"=>$this->input->post('from'),
				"to"=>$this->input->post('to'),
				'base_url' => base_url()
				));

				$report->run();

				$data = array(
					'report'=> $report
				);

				$this->load->view('index', $data);

}

view

    <?php 
      google\PieChart::create(array(
        "dataStore"=> $this->dataStore('payment'),
		"columns"=>array("type",
		"amount"=>array("prefix"=>"$")),
        "options"=>array(
          'title' => 'Payment By Type',
		  'pieSliceText'=>'value'
        ),
        "width"=>'100%',
        // 'height'=>'300px',
		"clientEvents"=>[
			"rowSelect"=>"function(params){
				window.location='<?php echo base_url(); ?>/reports/'+params.selectedRow[0];
			}"
		]
      ));
    ?>

ERROR

An uncaught Exception was encountered Type: Error

Message: Call to undefined method CI_Loader::dataStore()