Problems with JPGraph unable to display - php

Question

I am trying to retrieve the data from a mysql data and show it in a PHP page running a session. The code runs in a separate page. And the data is retrieved as Image in another page.
The main problem is no matter what kind of coding that I put above the default graph coding, it will become a broken image. FYI I have already enabled php_gd2.dll and the extension in my php.ini file is set to the extension folder. Are there any other fixes that has to be made in any of the files?
<?php
session_start();
if($_SESSION['username'])
{
require "dbc.php";
echo "<h2>Patient Glucose Data</h2>";
$username = $_SESSION['username'];
$query_view = mysql_query("SELECT * FROM user_glucose WHERE username='$username'");
$numrows = mysql_num_rows($query_view);
if ($numrows != 0)
{
while ($rows = mysql_fetch_assoc($query_view))
{
$print_day1 = $rows['Day1'];
$print_day2 = $rows['Day2'];
$print_day3 = $rows['Day3'];
$print_day4 = $rows['Day4'];
$print_day5 = $rows['Day5'];
$print_day6 = $rows['Day6'];
$print_day7 = $rows['Day7'];
$print_day8 = $rows['Day8'];
$print_day9 = $rows['Day9'];
$print_day10 = $rows['Day10'];
$print_day11 = $rows['Day11'];
$print_day12 = $rows['Day12'];
$print_day13 = $rows['Day13'];
$print_day14 = $rows['Day14'];
}
}
require('/jpgraph-3.5.0b1/src/jpgraph.php');
require('/jpgraph-3.5.0b1/src/jpgraph_line.php');
// data
$ydata =
array($print_day1,$print_day2,$print_day3,$print_day4,$print_day5,$print_day6,$print_day7,$print_day8,$print_day9);
// Create the graph. These two calls are always required
$graph = new Graph(500,500);
$graph->SetScale('textlin');
$graph->xaxis->title->Set("Number of Days");
$graph->yaxis->title->Set("Glucose Concentration");
// Create the linear plot
$lineplot=new LinePlot($ydata);
$lineplot->SetColor('blue');
// Add the plot to the graph
$graph->Add($lineplot);
// Display the graph
$graph->Stroke();
}
?>