$hd::size1 = scalar @{\@{$main::M[0]}};
	$hd::size  = $hd::size1 - 1;

	for ($hd::i=$hd::save; $hd::i<= $hd::size; $hd::i++) #this creates and adds to the hd array
	{
		$hd::store= [];
		for ($hd::j=0; $hd::j < $hd::i; $hd::j++)
		{
			$hd::temp = &hd($main::M[0][$hd::i], $main::M[0][$hd::j]);
			print $hd::temp;
			print "\n";
			push $hd::store, $hd::temp;
		}
		push @{$main::hd}, $hd::store;
	}
$hd::save = $hd::size


##</code><code>##

#!/usr/bin/perl
#ex2
use warnings;
use strict;
sub clust;


$main::hd=[[]];
$main::a = [0.25];
$main::b = [0.25,0.5];
$main::C = [1,0.75,0.75];
$main::hdt = 0.4;
$main::c = [];
$main::c1 = 1;
$main::c2 = 0.75;
$main::c3 = 0.75;
				#how to add elements to an array
push $main::c, $main::c1;
push $main::c, $main::c2;
push $main::c, $main::c3;
				#how to add arrays to arrays
push @{$main::hd}, $main::a;
push @{$main::hd}, $main::b;
push @{$main::hd}, $main::c;





&clust;
for ($loop::i=0; $loop::i<=3; $loop::i++)
{
	print $clust::cluster_ids->[$loop::i], "\n";
}



sub clust {
	use Algorithm::Cluster::Thresh;
	use Algorithm::Cluster qw/treecluster/;
	$clust::tree = treecluster(data=>$main::hd, method=>'a');
 	$clust::cluster_ids = $clust::tree->cutthresh($main::hdt);	
}