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# Before `make install' is performed this script should be runnable with
# `make test'. After `make install' it should work as `perl test.pl'

#########################

use Test;
BEGIN { plan tests => 5 };
use AI::DecisionTree;
ok(1); # If we made it this far, we're ok.

#########################

my $dtree = AI::DecisionTree->new(noise_mode => 'pick_best');
ok $dtree;

my @names = split /, /, <DATA>;
chomp $names[-1];

# Train on first 600 instances
printf "Loading 600 training instances with %d attribute types each\n", scalar @names;
while (<DATA>) {
  last unless 2..601;
  
  chomp;
  my @values = split /, /, $_;
  my $result = pop @values;
  my %pairs = map {$names[$_], $values[$_]} 0..$#names;

  $dtree->add_instance(attributes => \%pairs,
		       result => $result,
		      );
}
print "Building decision tree\n";
$dtree->train;
ok(1);

# Test on rest of data, get at least 80%
print "Testing on remainder of data\n";
my ($good, $bad) = (0,0);
while (<DATA>) {
  chomp;
  my @values = split /, /, $_;
  my $result = pop @values;
  my %pairs = map {$names[$_], $values[$_]} 0..$#names;

  my ($guess, $confidence) = $dtree->get_result(attributes => \%pairs);
  $guess ||= '';  $confidence ||= '';
  ($guess eq $result ? $good : $bad)++;
  
  #print "$guess : $result : $confidence\n";
}
my $accuracy = $good/($good + $bad);
ok $accuracy > .8;
print "Accuracy=$accuracy\n";

#use YAML; print Dump($dtree->rule_tree);
#print map "$_\n", $dtree->rule_statements;

if (eval "use GraphViz; 1") {
  my $graphviz = $dtree->as_graphviz;
  ok $graphviz;

  if (0) {
    # Only works on Mac OS X
    my $file = '/tmp/tree2.png';
    open my($fh), "> $file" or die "$file: $!";
    print $fh $graphviz->as_png;