Morris chart error when passing JSON data from PHP via AJAX -

i have data database put through json_encode following code:

$orderlist = $this->retrieve->retrieve_data('*'); $data = array(); foreach ($orderlist $order) {     array_push($data, array(         'd'     => $order['createddate'],         'sales' => $order['order_price']     )); } echo json_encode(array('data' => $data)); 

this output:

{"data":[{"d":"2015-09-26","sales":"0.00"},{"d":"2015-09-26","sales":"200.00"},{"d":"2015-09-26","sales":"45.00"},{"d":"2015-09-26","sales":"1500.00"}]} 

and javascript code:

$.ajax({     url: baseurl + '/memberinfo/getgraphicalactivity',     cache: false,     type: "post",     data: {patientfk: $("#patientfk").val()},     datatype: "json",     timeout:3000,     success : function (data) {         memberarea = new morris.line({         element: 'line-chart-memberinfo',         data: data,         xkey: 'd',         ykeys: ['sales'],         labels: ['sales'],         smooth: false,         parsetime:false,         resize: true         });     },     error : function (xmlhttprequest, textstatus, errorthrown) {         alert("error " + errorthrown);         if(textstatus==='timeout')             alert("request timed out");     } }); 

it returns error:

uncaught typeerror: cannot read property 'x' of undefined

why happening?

the issue in how building json data in php. here's code:

foreach ($orderlist $order) {     $arr[] = array(         'd'     => ''.$order['createddate'].'',         'sales' => ''.$order['order_price'].'',     ); } echo json_encode($arr);