Here's a snippet from something I did with GD::Graph that read from a flat file: 
foreach (@lines)
{
    # Lines in the file look like:
    # Sun Jul 07 2002 10:03:03 Sensor 0 [100D973000080069] C: 25.1 F: 
+77.1
    chomp;
    my ($day, $mon, $date, $year, $time, undef, $sensor, undef, undef,
+ $c, undef, $f) = split;
    push (@{$data[0]}, $day);
    push (@{$data[$sensor + 1]}, $f);
    
    $y_max = $y_max > $f ? $y_max : $f;
    $y_min = $y_min < $f ? $y_min : $f;
}

my $y_axis_max = ceil($y_max / 10) * 10;
my $y_axis_min = floor($y_min / 10) * 10;
my $y_ticks = ($y_axis_max - $y_axis_min) / 10;

my $graph = new GD::Graph::lines();

$graph->set( 
    x_label => 'Day',
    y_label => 'Temperature (F)',
    title => $title,
    y_max_value => $y_axis_max,
    y_min_value => $y_axis_min,
    y_tick_number => 16,
    y_label_skip => 2,
    box_axis => 1,
    line_width => 3,
    y_label_position => 1,
    x_label_skip => 48,
    x_tick_offset => 48,
    x_long_ticks => 1,
    transparent => 0,
);

$graph->set_legend(@legend_labels);
$graph->plot($data);
save_chart($graph, "$img_path/$img_file");

[download]
Note that all arrays passed to plot() should be the same size. If they're not, pad the beginning of any short arrays with undef.

BTW, I've since switched from using a flat file to a MySQL database, and from GD::Graph to Chart::Graph::Gnuplot. I like Chart::Graph::Gnuplot because of the amount of control Gnuplot gives over the graph. If you've ever created Gnuplot input files yourself, you'll appreciate this module. Of course, some may consider it a drawback that it relies on an external program.

In reply to Re: Coaking GDGraph to work... by iguanodon
in thread Coaking GDGraph to work... by zakzebrowski

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