in reply to Creating a Histogram

You should do this, you break your HTML page into one script and your graph into another script. Within your HTML page you call the graph script passing it parameters that it will need to draw the graph. 
<!-- Your HTML page -->
<html>
<body>
<h1>My Graph</h1>
<p><img src="graphic.pl?width=100&height=100">
</body>
</html>

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Now your script that will return the graph, 
use CGI;

my $q = CGI->new();

my $height = $q->param('height');
my $width  = $q->param('width');

#
# Include you GD stuff here...
#

[download]

I realize that this is not complete but neither is the code that you gave us to work with... :)

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