joshua.decoder.ff.FeatureFunction Interface Reference

Inheritance diagram for joshua.decoder.ff.FeatureFunction:

List of all members.

Public Member Functions
void	setFeatureID (int id)
int	getFeatureID ()
void	setWeight (double weight)
double	getWeight ()
boolean	isStateful ()
void	setStateID (int stateID)
int	getStateID ()
double	estimateLogP (Rule rule, int sentID)
double	estimateFutureLogP (Rule rule, DPState curDPState, int sentID)
double	transitionLogP (Rule rule, List< HGNode > antNodes, int spanStart, int spanEnd, SourcePath srcPath, int sentID)
double	transitionLogP (HyperEdge edge, int spanStart, int spanEnd, int sentID)
double	finalTransitionLogP (HGNode antNode, int spanStart, int spanEnd, SourcePath srcPath, int sentID)
double	finalTransitionLogP (HyperEdge edge, int spanStart, int spanEnd, int sentID)

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Detailed Description

This interface provide ways to calculate logP based on rule and state information. In order to implement a new feature function you must (1) implement this FeatureFunction interface, and (2) implement the FFTransitionResult and FFDPState interfaces. BUG: the distinction between those latter two interfaces is unclear.

Author:

wren ng thornton wren@.nosp@m.user.nosp@m.s.sou.nosp@m.rcef.nosp@m.orge..nosp@m.net

Zhifei Li, zhife.nosp@m.i.wo.nosp@m.rk@gm.nosp@m.ail..nosp@m.com

Version:

$LastChangedDate$

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Member Function Documentation

double joshua.decoder.ff.FeatureFunction.estimateFutureLogP	(	Rule	rule,
		DPState	curDPState,
		int	sentID
	)

estimate future logP, e.g., the logPs of partial n-grams asscociated with the left-edge ngram state

Implemented in joshua.decoder.ff.lm.LanguageModelFF, joshua.decoder.ff.DefaultStatelessFF, and joshua.decoder.ff.similarity.EdgePhraseSimilarityFF.

double joshua.decoder.ff.FeatureFunction.estimateLogP	(	Rule	rule,
		int	sentID
	)

sentID might be useful for sentence-specific features (e.g., oralce model) It is used when initializing translation grammars (for pruning purpose, and to get stateless logP for each rule). This is also required to sort the rules (required by Cube-pruning).

Implemented in joshua.decoder.ff.lm.LanguageModelFF, and joshua.decoder.ff.similarity.EdgePhraseSimilarityFF.

Here is the caller graph for this function:

double joshua.decoder.ff.FeatureFunction.finalTransitionLogP	(	HGNode	antNode,
		int	spanStart,
		int	spanEnd,
		SourcePath	srcPath,
		int	sentID
	)

Edges calling finalTransition do not have concret rules associated with them.

Implemented in joshua.decoder.ff.similarity.EdgePhraseSimilarityFF, joshua.decoder.ff.lm.LanguageModelFF, and joshua.decoder.ff.DefaultStatelessFF.

double joshua.decoder.ff.FeatureFunction.finalTransitionLogP	(	HyperEdge	edge,
		int	spanStart,
		int	spanEnd,
		int	sentID
	)

Implemented in joshua.decoder.ff.DefaultStatelessFF, and joshua.decoder.ff.DefaultStatefulFF.

int joshua.decoder.ff.FeatureFunction.getFeatureID

(

)

Implemented in joshua.decoder.ff.DefaultStatelessFF, and joshua.decoder.ff.DefaultStatefulFF.

int joshua.decoder.ff.FeatureFunction.getStateID

(

)

Implemented in joshua.decoder.ff.DefaultStatelessFF, and joshua.decoder.ff.DefaultStatefulFF.

double joshua.decoder.ff.FeatureFunction.getWeight

(

)

Implemented in joshua.decoder.ff.DefaultStatelessFF, and joshua.decoder.ff.DefaultStatefulFF.

boolean joshua.decoder.ff.FeatureFunction.isStateful

(

)

Implemented in joshua.decoder.ff.DefaultStatelessFF, and joshua.decoder.ff.DefaultStatefulFF.

void joshua.decoder.ff.FeatureFunction.setFeatureID

(

int

id

)

It is essential to make sure the feature ID is unique for each feature.

void joshua.decoder.ff.FeatureFunction.setStateID

(

int

stateID

)

void joshua.decoder.ff.FeatureFunction.setWeight

(

double

weight

)

double joshua.decoder.ff.FeatureFunction.transitionLogP	(	Rule	rule,
		List< HGNode >	antNodes,
		int	spanStart,
		int	spanEnd,
		SourcePath	srcPath,
		int	sentID
	)

Implemented in joshua.decoder.ff.lm.LanguageModelFF, joshua.decoder.ff.DefaultStatelessFF, joshua.decoder.ff.similarity.EdgePhraseSimilarityFF, and joshua.decoder.ff.SourcePathFF.

double joshua.decoder.ff.FeatureFunction.transitionLogP	(	HyperEdge	edge,
		int	spanStart,
		int	spanEnd,
		int	sentID
	)

Implemented in joshua.decoder.ff.DefaultStatelessFF, and joshua.decoder.ff.DefaultStatefulFF.