edu.umn.cs.nlp.mt
Class AlignmentMatrix

java.lang.Object
  edu.umn.cs.nlp.mt.AlignmentMatrix

public class AlignmentMatrix
extends Object

Represents a word alignment matrix for an aligned sentence pair in a machine translation system.

Initial phrase pairs and hierarchical rules may be extracted from an alignment matrix, based on the constraints described in (Chiang, 2005).

Version:

$LastChangedDate: 2007-09-11 08:39:02 -0500 (Tue, 11 Sep 2007) $

Author:

Lane Schwartz

See Also:

"A Hierarchical Phrase-Based Model for Statistical Machine Translation" by David Chiang (ACL, 2005)

Nested Class Summary

class	AlignmentMatrix.AlignmentFormattingException
class	AlignmentMatrix.EmptySentenceException
class	AlignmentMatrix.RunOnSentenceException

Field Summary

static String	DELIMITER
static int	MAX_SENTENCE_LENGTH

Constructor Summary

AlignmentMatrix(String sourceLine, String targetLine, String alignmentLine, LexicalTranslationProbabilityDistribution lexProbs)

Method Summary

void	extractBasicPhrasePairs()
void	extractCompositePhrasePairs()
protected List<PhrasePair>	getBasicPhrasePairs()
protected List<PhrasePair>	getCompositePhrasePairs()
protected double	getNumberExtractedFrom(PhrasePair p)
String	getPhrasePairsAsString()
static void	main(String[] args)
String	phrasePairToString(PhrasePair p) Convert a PhrasePair to a String.
String	phrasePairToString(PhrasePair p, PhrasePair nonterminal)
String	phrasePairToString(PhrasePair p, PhrasePair nt1, PhrasePair nt2)

Methods inherited from class java.lang.Object

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

Field Detail

MAX_SENTENCE_LENGTH

public static final int MAX_SENTENCE_LENGTH

See Also:

Constant Field Values

DELIMITER

public static final String DELIMITER

See Also:

Constant Field Values

Constructor Detail

AlignmentMatrix

public AlignmentMatrix(String sourceLine,
                       String targetLine,
                       String alignmentLine,
                       LexicalTranslationProbabilityDistribution lexProbs)

Method Detail

main

public static void main(String[] args)

getBasicPhrasePairs

protected List<PhrasePair> getBasicPhrasePairs()

getCompositePhrasePairs

protected List<PhrasePair> getCompositePhrasePairs()

extractBasicPhrasePairs

public void extractBasicPhrasePairs()

extractCompositePhrasePairs

public void extractCompositePhrasePairs()

getPhrasePairsAsString

public String getPhrasePairsAsString()

phrasePairToString

public String phrasePairToString(PhrasePair p)

Convert a PhrasePair to a String.

The returned string will have the following format:

source_phrase ::: target_phrase ::: source_given_target_lex_prob ::: target_given_source_lex_prob ::: weight

Parameters:

p -

Returns:

getNumberExtractedFrom

protected double getNumberExtractedFrom(PhrasePair p)

phrasePairToString

public String phrasePairToString(PhrasePair p,
                                 PhrasePair nonterminal)

phrasePairToString

public String phrasePairToString(PhrasePair p,
                                 PhrasePair nt1,
                                 PhrasePair nt2)