for my $i($#classArr) {
  print "subArr_ref: ".@{$classArr[$i]}."\n";
  for my $hashRef(@{$classArr[$i]}) { 
    print "hashRef: ".$hashRef."\n";
    for my $key (sort keys %$hashRef) {
      print $csv $key."-- ".$hashRef->{$key}.",";
    }
    # foreach my $feat(@featureVector) {
    #   print $csv $hashRef->{$feat}.",";
    # }
    print $csv $i."\n";
  }
}