สอบถามเกี่ยวกับ JPgraph หน่อยครับ ผมติดปัญหา กราฟ ไม่ขึ้นครับ

print_r($datay);

<iframe src="JpGraph.php" height="600" width="700" ></iframe>

<?php // content="text/plain; charset=utf-8"
require_once ('jpgraph/src/jpgraph.php');
require_once ('jpgraph/src/jpgraph_bar.php');

$objConnect = mysql_connect("localhost","root","1234") or die("Error Connect to Database");
$objDB = mysql_select_db("JpGraph");
$strSQL = "select * from check_in";
$objQuery = mysql_query($strSQL);
$data = array();
while($result = mysql_fetch_array($objQuery))
{
	$data []=$result["test_in"];
}


// Create the graph. These two calls are always required
$graph = new Graph(350,200,'auto');
$graph->SetScale("textlin");

$theme_class=new UniversalTheme;
$graph->SetTheme($theme_class);

$graph->yaxis->SetTickPositions(array(0,30,60,90,120,150), array(15,45,75,105,135));
$graph->SetBox(false);

$graph->ygrid->SetFill(false);
$graph->xaxis->SetTickLabels(array('A','B','C','D','E','F'));
$graph->yaxis->HideLine(false);
$graph->yaxis->HideTicks(false,false);

// Create the bar plots
$b1plot = new BarPlot($data);


// Create the grouped bar plot
$gbplot = new GroupBarPlot(array($b1plot));
// ...and add it to the graPH
$graph->Add($gbplot);


$b1plot->SetColor("white");
$b1plot->SetFillColor("#cc1111");


$graph->title->Set("Bar Plots");

// Display the graph
$graph->Stroke();
?>

// เตรียมข้อมุลที่จะแสดง เพื่อสร้างกราฟ
$datay=array();
while($objResult = mysql_fetch_array($objQuery))
{
$data[] = $objResult["test_in"]; 
}