GD::Graph

use GD::Graph::lines;
require 'save.pl';

print STDERR "Processing sample56 (experimental)\n";

@data = read_data("sample54.dat")
or die "Cannot read data from sample54.dat";

$my_graph = new GD::Graph::lines();

$my_graph->set(
x_label => 'Wavelength (nm)',
y_label => 'Absorbance',
title => 'Numerical X axis',

y_min_value => 0,
y_max_value => 2,
y_tick_number => 8,
y_label_skip => 4,

x_tick_number => 14,
x_min_value => 100,
x_max_value => 800,
x_ticks => 1,
x_tick_length => -4,
x_long_ticks => 1,
x_label_skip => 2,
x_tick_offset => 2,

no_axes => 1,
line_width => 2,
x_label_position => 1/2,
r_margin => 15,

transparent => 0,
);

$my_graph->set_legend('Thanks to Scott Prahl and Gary Deschaines');
$my_graph->plot(\@data);
save_chart($my_graph, 'sample56');


sub read_data
{
my $fn = shift;
local(*ZZZ);
my @d = ();

open(ZZZ, $fn) || return ();

while ()
{
chomp;
my @row = split;

for (my $i = 0; $i <= $#row; $i++)
{
undef $row[$i] if ($row[$i] eq 'undef');
unshift @{$d[$i]}, $row[$i];
}
}

close (ZZZ);

return @d;
}