sub NearestNeighbours {
	#call as NearestNeighbours(\@Matrix)
	$sumNN=0; #initialize sum
	my $numberofsamples=scalar(@Matrix)/2;
	my $counter_outer=$numberofsamples;
	my $counter_inner=$numberofsamples;
	my ($xDNM, $yDNM, $xMoves, $yMoves,$i,$j);
OUTER:    for ($i = 1; $i <= $counter_outer; $i++) {
			    my $NearestNeighbour=1000000;#initialize to something insanely large
				my $distance = 0; #initialize distance
  				my $c=(2*$i-1);
	 			$xDNM=@Matrix[$c-1]; #xDoesNotMove
	 			$yDNM=@Matrix[$c];	 
	    INNER: for ($j = 1; $j <= $counter_inner; $j++) {
			 		my $d=(2*$j-1);		 
					 if ($c==$d) {next INNER}
		 			$xMoves=@Matrix[$d-1];
		 			$yMoves=@Matrix[$d];
		 			$distance = sqrt(($xDNM-$xMoves)^2+($yDNM-$yMoves)^2);
		 			if ($distance<$NearestNeighbour) {$NearestNeighbour=$distance}		 							
					} # next comparison for this sample
		$sumNN=$sumNN+$NearestNeighbour;
		} #next sample	
	return ($sumNN);
}# end of sub.