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");