use strict;
use warnings;
use diagnostics;

my @aoh;
	push @aoh, {
		"start" => .4,
		"stop" => .6,
		"step" => .1 
	};
	push @aoh, {
		"start" => .3,
		"stop" => .5,
		"step" => .1
	};
	push @aoh, {
		"start" => .0,
		"stop" => .2,
		"step" => .1
	};
	push @aoh, {
		"start" => .5,
		"stop" => .7,
		"step" => .1
	};
my $aoh = \@aoh;

for my $point ( @{$aoh}) {
	#for my $type ( sort keys %$point ) {
	for my $type ( sort by_pref keys %$point ) {
		print "$type\t";
	}
	print "\n";
}

sub by_pref {
	$a cmp $b;
	#advice?
}