can't shown value in line chart

[Anonymous]

Hi all ,
I want to retrieve data from mysql  and using these to produce JSON , but when I show in browser , the line char only shown $data_1 and $data_2 ,
But can't shown $data_3 , anyone knows what's happen ?
Let me know if you need any help , please !

<?php
include "open-flash-chart.php";
        $link = mysql_connect("Server_IP", "id", "pwd") or die("Could not connect : " . mysql_error());
        mysql_select_db("db_name") or die("Could not select database");  

        $sql = "select value  from result  where id1 =1 and id2 = 2  limit 10";
       
        $result = mysql_query($sql);
                if (!$result) {
            die("Query to show fields from table failed");
                }
                $result_num = mysql_num_rows($result);
               
$data_1 = array();
$data_2 = array();
$data_3 = array();
while ($row = mysql_fetch_array($result))
{
       
        $t = $row;
       
        $data_1 = 50;
      $data_2 = 80;
        $data_3 = $t;
}

$title = new title( date("D M d Y") );
$line_1_default_dot = new dot();
$line_1_default_dot->colour('#f00000');
$line_1 = new line();
$line_1->set_default_dot_style($line_1_default_dot);
$line_1->set_values( $data_1 );
$line_1->set_width( 1 );
// ----- LINE 2 ---
$line_2_default_dot = new dot();
$line_2_default_dot->size(3)->halo_size(1)->colour('#3D5C56');
$line_2 = new line();
$line_2->set_default_dot_style($line_2_default_dot);
$line_2->set_values( $data_2 );
$line_2->set_width( 2 );
$line_2->set_colour( '#3D5C56' );
// ----- LINE 2 ---
$line_3_default_dot = new dot();
$line_3_default_dot->size(4)->halo_size(2);
$line_3 = new line();
$line_3->set_default_dot_style($line_3_default_dot);
$line_3->set_values( $data_3 );
$line_3->set_width( 6 );
$y = new y_axis();
$y->set_range( 0, 120, 10 );
$chart = new open_flash_chart();
$chart->set_title( $title );
$chart->add_element( $line_1 );
$chart->add_element( $line_2 );
$chart->add_element( $line_3 );
$chart->set_y_axis( $y );
mysql_close($link);
echo $chart->toPrettyString();
?>

Cheers,
Stefan