gov.sandia.cognition.learning.algorithm.tree

Class DecisionTree<InputType,OutputType>

java.lang.Object

gov.sandia.cognition.util.AbstractCloneableSerializable

gov.sandia.cognition.learning.algorithm.tree.DecisionTree<InputType,OutputType>

Type Parameters:

InputType - The input type of the decision tree to evaluate

OutputType - The output type that the decision tree returns.

All Implemented Interfaces:

Evaluator<InputType,OutputType>, CloneableSerializable, java.io.Serializable, java.lang.Cloneable

Direct Known Subclasses:

CategorizationTree, RegressionTree

public class DecisionTree<InputType,OutputType>
extends AbstractCloneableSerializable
implements Evaluator<InputType,OutputType>

The DecisionTree class implements a standard decision tree that is made up of DecisionTreeNode objects. It contains the root node of the tree plus the code that descends the decision tree to come up with a result value.

Since:

2.0

Author:

Justin Basilico

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected DecisionTreeNode<InputType,OutputType>	rootNode The root node of the decision tree.

Constructor Summary

Constructors

Constructor and Description
DecisionTree() Creates a new instance of DecisionTree.
DecisionTree(DecisionTreeNode<InputType,OutputType> rootNode) Creates a new instance of DecisionTree.

Method Summary

Modifier and Type	Method and Description
DecisionTree<InputType,OutputType>	clone() This makes public the clone method on the Object class and removes the exception that it throws.
OutputType	evaluate(InputType input) Evaluates the decision tree against the given input.
OutputType	evaluateNode(InputType input, DecisionTreeNode<InputType,OutputType> node) Evaluates an input against the given node of a decision tree, using recursion to come up with the answer.
DecisionTreeNode<InputType,OutputType>	findTerminalNode(InputType input) Finds the terminal node for the given input.
DecisionTreeNode<InputType,OutputType>	findTerminalNode(InputType input, DecisionTreeNode<InputType,OutputType> node) Finds the terminal node for the given input, starting from the given node.
DecisionTreeNode<InputType,OutputType>	getRootNode() Gets the root node of the decision tree.
void	setRootNode(DecisionTreeNode<InputType,OutputType> rootNode) Sets the root node of the decision tree.

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

rootNode

protected DecisionTreeNode<InputType,OutputType> rootNode

The root node of the decision tree.

Constructor Detail

DecisionTree

public DecisionTree()

Creates a new instance of DecisionTree.

DecisionTree

public DecisionTree(DecisionTreeNode<InputType,OutputType> rootNode)

Creates a new instance of DecisionTree.

Parameters:

rootNode - The root node of the tree.

Method Detail

clone

public DecisionTree<InputType,OutputType> clone()

Description copied from class: AbstractCloneableSerializable

This makes public the clone method on the Object class and removes the exception that it throws. Its default behavior is to automatically create a clone of the exact type of object that the clone is called on and to copy all primitives but to keep all references, which means it is a shallow copy. Extensions of this class may want to override this method (but call super.clone() to implement a "smart copy". That is, to target the most common use case for creating a copy of the object. Because of the default behavior being a shallow copy, extending classes only need to handle fields that need to have a deeper copy (or those that need to be reset). Some of the methods in ObjectUtil may be helpful in implementing a custom clone method. Note: The contract of this method is that you must use super.clone() as the basis for your implementation.

Specified by:

clone in interface CloneableSerializable

Overrides:

clone in class AbstractCloneableSerializable

Returns:

A clone of this object.

evaluate

public OutputType evaluate(InputType input)

Evaluates the decision tree against the given input.

Specified by:

evaluate in interface Evaluator<InputType,OutputType>

Parameters:

input - The input to evaluate.

Returns:

The output of the decision tree for the given input.

evaluateNode

public OutputType evaluateNode(InputType input,
                               DecisionTreeNode<InputType,OutputType> node)

Evaluates an input against the given node of a decision tree, using recursion to come up with the answer.

Parameters:

input - The input to evaluate.

node - The node at which to evaluate.

Returns:

The output of the decision tree for the given input.

findTerminalNode

public DecisionTreeNode<InputType,OutputType> findTerminalNode(InputType input)

Finds the terminal node for the given input. The terminal node is the node in the tree that the input will use to produce an output. It is usually the case that it is a leaf node, but it is not required, since it may happen that the decision function finds a node that has no child for that input. In this case, this is the node returned.

Parameters:

input - The input to find the terminal node for.

Returns:

The terminal node for the input, starting from the root node.

findTerminalNode

public DecisionTreeNode<InputType,OutputType> findTerminalNode(InputType input,
                                                               DecisionTreeNode<InputType,OutputType> node)

Finds the terminal node for the given input, starting from the given node. The terminal node is the node in the tree that the input will use to produce an output. It is usually the case that it is a leaf node, but it is not required, since it may happen that the decision function finds a node that has no child for that input. In this case, this is the node returned.

Parameters:

input - The input to find the terminal node for.

node - The node to search from.

Returns:

The terminal node for the input, starting from the root node.

getRootNode

public DecisionTreeNode<InputType,OutputType> getRootNode()

Gets the root node of the decision tree.

Returns:

The root node of the decision tree.

setRootNode

public void setRootNode(DecisionTreeNode<InputType,OutputType> rootNode)

Sets the root node of the decision tree.

Parameters:

rootNode - The root node of the decision tree.