use strict;
use warnings;
use Chart::Gnuplot;

my @data = ();
for my $x (0..100) {
  for my $y (0..100) {
    push @data, [$x / 10, $y / 10, ($x**2 - $y**2) / 100];
  }
  push @data, []; # need an empty arrayref between blocks to simulate a newline
}

my $chart = Chart::Gnuplot->new(
    output => "test1.png",
    title  => "3D plot from arrays of x, y and z coordinates",
    xlabel => 'x',
    ylabel => 'y',
);
$chart->set(pm3d => 'map');
$chart->set(palette => 'defined (0 0 0 1, 1 1 1 0, 2 1 0 0)');
$chart->set(contour => 'base');

my $dataSet = Chart::Gnuplot::DataSet->new(
    points => \@data,
);

$chart->plot3d($dataSet);