无法通过饼图在PHP中传递值

I have a page1.php with image scr="pieGraph.php" inside it. And in my pieGraph.php i have a code like this:

session_start();
if(isset($_SESSION['test']))
{
  $_SESSION['test'] = $_SESSION['test'];
}
else
{ 
  $_SESSION['test'] = 0;
}

$val1 = $_SESSION['test'];
$val2 = 30;
$val3 = 40;
$val4 = 50;
$val5 = 10;
 /* CAT:Pie charts */ 

 /* pChart library inclusions */ 
 include("chart/class/pData.class.php"); 
 include("chart/class/pDraw.class.php"); 
 include("chart/class/pPie.class.php"); 
 include("chart/class/pImage.class.php"); 

 /* Create and populate the pData object */ 
 $MyData = new pData();    
 $MyData->addPoints(array($val1,$val2,$val3,$val4,$val5),"ScoreA");   
 $MyData->setSerieDescription("ScoreA","Application A"); 

 /* Render the picture (choose the best way) */ 
$myPicture->autoOutput("pictures/example.draw2DRingValue.png"); 
?>

But session in this page doesn't work. Dont know why. Please help guys.

Thanks for the help guys :)) I already solved my problem :))) Thanks for this link how to retrieve data from field name and column to generate graph

So far this was my code:

 <?php
date_default_timezone_set("Asia/Manila");
session_start();
include ("inc/dbcon.php"); 

if(isset($_SESSION['campaign']))
{
    $_SESSION['campaign'] = $_SESSION['campaign'];
}
else
{
$_SESSION['camapign'] = 'CEBU PACIFIC';
} 
if(isset($_SESSION['team']))
{
$_SESSION['team'] = $_SESSION['team'];
}
else
{
$_SESSION['team'] = 'TEAM AENNAH';
} 
if(isset($_SESSION['date']))
{
$_SESSION['date'] = $_SESSION['date'];
}
else
{
$_SESSION['date'] = "1999-01-01";
} 

$val1 = 100;
$val2 = 30;
$val3 = 40;
$val4 = 50;
$val5 = 10;
 /* CAT:Pie charts */ 

/* pChart library inclusions */ 
include("chart/class/pData.class.php"); 
include("chart/class/pDraw.class.php"); 
include("chart/class/pPie.class.php"); 
include("chart/class/pImage.class.php"); 

/* Create and populate the pData object */ 
$MyData = new pData();    
$query = mysql_query("SELECT * FROM tbl_projected WHERE          fd_campaign='$_SESSION[campaign]' AND fd_team='$_SESSION[team]' AND   fd_date='$_SESSION[date]'") or die(mysql_error());
if(mysql_num_rows($query) == 0)
{   
$MyData->addPoints(array($val1,$val2,$val3,$val4,$val5),"ScoreA");   
$MyData->setSerieDescription("ScoreA","Application A");
}
else 
{
while($row = mysql_fetch_array($query))
{
$MyData->addPoints(array($row['fd_Bill_Calling_hrs'], $row['fd_Bill_Training_hrs'],    $row['fd_Bill_Support_hrs'], $row['fd_Bill_OT_hrs'], $row['fd_Bill_HO_OT_hrs'])); 
$MyData->setSerieDescription("ScoreA","Application A"); 
}
 }  

Hope this will help others too :))