Class: HybridForest::Trees::TreeGrowers::ID3Grower

Inherits:
Object
  • Object
show all
Includes:
Observable
Defined in:
lib/hybridforest/trees/tree_growers/id3_grower.rb

Instance Method Summary collapse

Constructor Details

#initialize(feature_selector: MaxOneSplitPerFeature.new, impurity_metric: Entropy.new) ⇒ ID3Grower

Returns a new instance of ID3Grower.



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# File 'lib/hybridforest/trees/tree_growers/id3_grower.rb', line 24

def initialize(feature_selector: MaxOneSplitPerFeature.new, impurity_metric: Entropy.new)
  @impurity_metric = impurity_metric
  @feature_selector = feature_selector
  add_observer(@feature_selector)
end

Instance Method Details

#grow_tree(instances, parent_instances = nil) ⇒ Object 



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# File 'lib/hybridforest/trees/tree_growers/id3_grower.rb', line 30

def grow_tree(instances, parent_instances = nil)
  features = remaining_features(instances)

  if instances.count == 0
    LeafNode.new(parent_instances)
  elsif instances.pure? || features.count == 0
    LeafNode.new(instances)
  else
    try_to_split_dataset(instances, features)
  end
end