I am trying to plot a simple line graph on a web page using the GDGraph module. So far all i seem to get after i ran my script is an empty image My code is as follows: 
#!/usr/local/bin/perl5

use GD::Graph;
use GD::Graph::lines;
use CGI;
my $query = new CGI;

 @data = ( 
    ["1st","2nd","3rd","4th","5th","6th","7th", "8th", "9th"],
    [    1,    2,    5,    6,    3,  1.5,    1,     3,     4],
    [ sort { $a <=> $b } (1, 2, 5, 6, 3, 1.5, 1, 3, 4) ]
  );

    my $format;

    print "Content-type: image/png\n\n";
    
    # create a new graph
    my $graph =  GD::Graph::lines->new(400,400);
        
    $graph->set( x_label           => 'X Label',
          y_label           => 'Y label',
          title             => 'Some simple graph',
         );
    
    $format = $graph->export_format;
    
    print $query->header("image/$format");
    
    binmode STDOUT;

   #(the parentheses after $format are necessary, to help the compiler
+ decide that 
   # you mean a method name here) 
   print $graph->plot(\@data)->$format();

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In reply to GDGraph charts by Anonymous Monk

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