edu.umn.cs.nlp.mt.huangchiang2005
Class Hyperarc<Node extends Vertex,Parse extends Derivation>

java.lang.Object
  edu.umn.cs.nlp.mt.huangchiang2005.Hyperarc<Node,Parse>

Direct Known Subclasses:

RuleApplication

public abstract class Hyperarc<Node extends Vertex,Parse extends Derivation>
extends Object

Version:

$LastChangedDate: 2007-11-05 15:21:19 -0600 (Mon, 05 Nov 2007) $

Author:

Lane Schwartz

See Also:

"Better k-best Parsing" by Liang Huang & David Chiang (IWPT, 2005)

Field Summary

protected Node	head
protected List<Node>	tail

Constructor Summary

Hyperarc(Node head, List<Node> tail)

Method Summary

int	arity()
abstract Parse	getDerivation(List<Parse> children)
abstract double	getWeight()
boolean	isSourceVertex()
List<Parse>	naiveMult(int k) Gets the k-best derivations using the naive mult algorithm from Huang & Chiang (2005).
List<Node>	tail()

Methods inherited from class java.lang.Object

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

Field Detail

head

protected final Node extends Vertex head

tail

protected final List<Node extends Vertex> tail

Constructor Detail

Hyperarc

public Hyperarc(Node head,
                List<Node> tail)

Method Detail

tail

public List<Node> tail()

arity

public int arity()

isSourceVertex

public boolean isSourceVertex()

getWeight

public abstract double getWeight()

getDerivation

public abstract Parse getDerivation(List<Parse> children)

naiveMult

public List<Parse> naiveMult(int k)

Gets the k-best derivations using the naive mult algorithm from Huang & Chiang (2005).

This method has an overall time complexity of O(r * k^r * log k) where r is the arity of this Hyperarc.

Parameters:

k - The number of derivations to extract

Returns:

The k-best derivations of this arc

See Also:

4.1 of "Better k-best Parsing" by Liang Huang & David Chiang (IWPT, 2005)