AI::DecisionTree::Instance - C-struct wrapper for training instances

  use AI::DecisionTree::Instance;

  my $i = new AI::DecisionTree::Instance([3,5], 7, 'this_instance');
  $i->value_int(0) == 3;
  $i->value_int(1) == 5;
  $i->result_int == 7;

This class is just a simple Perl wrapper around a C struct embodying a single training instance. Its purpose is to reduce memory usage. In a "typical" training set with about 1000 instances, memory usage can be reduced by about a factor of 5 (from 43.7M to 8.2M in my test program).

A fairly tight loop is also implemented that helps speed up the train() AI::DecisionTree method by about a constant factor of 4.

Please do not consider this interface stable - I change it whenever I have a new need in AI::DecisionTree.

Ken Williams, ken@mathforum.org

AI::DecisionTree