title: The "jpgraph" not working, without errors in html
body: <p>This is my PHP code:</p>
  
  <pre><code>require_once ('jpgraph/jpgraph.php');
  require_once ('jpgraph/jpgraph_bar.php');
  
  $data1y=array(47,80,40,116);
  $data2y=array(61,30,82,105);
  $data3y=array(115,50,70,93);
  
  
  // Create the graph. These two calls are always required
  $graph = new Graph(350,200,'auto');
  $graph-&gt;SetScale("textlin");
  
  $theme_class=new UniversalTheme;
  $graph-&gt;SetTheme($theme_class);
  
  $graph-&gt;yaxis-&gt;SetTickPositions(array(0,30,60,90,120,150), array(15,45,75,105,135));
  $graph-&gt;SetBox(false);
  
  $graph-&gt;ygrid-&gt;SetFill(false);
  $graph-&gt;xaxis-&gt;SetTickLabels(array('A','B','C','D'));
  $graph-&gt;yaxis-&gt;HideLine(false);
  $graph-&gt;yaxis-&gt;HideTicks(false,false);
  
  // Create the bar plots
  $b1plot = new BarPlot($data1y);
  $b2plot = new BarPlot($data2y);
  $b3plot = new BarPlot($data3y);
  
  // Create the grouped bar plot
  $gbplot = new GroupBarPlot(array($b1plot,$b2plot,$b3plot));
  // ...and add it to the graPH
  $graph-&gt;Add($gbplot);
  
  
  $b1plot-&gt;SetColor("white");
  $b1plot-&gt;SetFillColor("#cc1111");
  
  $b2plot-&gt;SetColor("white");
  $b2plot-&gt;SetFillColor("#11cccc");
  
  $b3plot-&gt;SetColor("white");
  $b3plot-&gt;SetFillColor("#1111cc");
  
  $graph-&gt;title-&gt;Set("Bar Plots");
  
  // Display the graph
  $graph-&gt;Stroke();
  </code></pre>
  
  <p>Reference: <a href="http://jpgraph.net/features/src/show-example.php?target=new_line1.php" rel="nofollow noreferrer">JpGraph Example - Chart</a></p>
  
  <p>This is my HTML:</p>
  
  <p><a href="https://i.stack.imgur.com/VwFn7.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/VwFn7.png" alt="image"></a></p>
  
  <p>There is no error message on screen. Browser's console is empty as well.</p>
  
  <p>What could be wrong? Do I need to set up something?</p>
  
  <p>I have tried this link: <a href="https://stackoverflow.com/questions/14069477/jpgraph-doesnt-work">jpgraph doesn't work</a> but without success.</p>