Am trying to graph about 590 data points on a line graph. The output shows a large black rectangle. What am I doing wrong: 
sub graphtest
  {
  
  $my_graph = new GD::Graph::lines(800, 600);
  
  my $data  = new GD::Graph::Data(
      [
        @{$dataarrays{'time'}}
      , @{$dataarrays{'page ins (x1000)'}}
#      , @{$dataarrays{'cpu system %'}},
      ]
      );
  
  $my_graph->set( 
      x_label => 'Time',
#      y_label => 'Y label',
      title => 'Load Analysis '.$store,
      y_max_value => 100,
      y_tick_number => 6,
      y_label_skip => 2,
      x_label_skip => 20,
  
      transparent => 0,
  );
  
#  $my_graph->set_legend( 'page ins (x1000)' );
  $my_graph->plot(\@data);
  &save_chart($my_graph, $receivedir . 'loadanalysis');
  }

#-----------------------------------------------------
#
sub save_chart
{
    my $chart = shift or die "Need a chart!";
    my $name = shift or die "Need a name!";
    local(*OUT);


    open(OUT, ">$name.gif") or 
        die "Cannot open $name.gif for write: $!";
    binmode OUT;
    print OUT $chart->gd->gif();
    close OUT;
}

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A dump of %dataarrays shows it to be, apparently, ok. Any suggestions?
pat

In reply to GD Graph: gif comes out a large black rectangle. by pmneve

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