burlap.behavior.singleagent.vfa

Interface FeatureDatabase

All Known Implementing Classes:

CMACFeatureDatabase, FourierBasis, FVCMACFeatureDatabase, FVRBFFeatureDatabase, FVToFeatureDatabase, RBFFeatureDatabase

public interface FeatureDatabase

An interface for defining a database of state features that can be returned for any given input state or input state-action pair.

Author:

James MacGlashan

Method Summary

Methods

Modifier and Type	Method and Description
FeatureDatabase	copy() Returns a deep copy of this feature database.
void	freezeDatabaseState(boolean toggle) Enable or disable the database from generating new features.
java.util.List<ActionFeaturesQuery>	getActionFeaturesSets(State s, java.util.List<GroundedAction> actions) Returns non-zero action features for all of provided actions in state s.
java.util.List<StateFeature>	getStateFeatures(State s) Returns non-zero state features for a given state.
int	numberOfFeatures() Returns the number of features this database tracks.

Method Detail

getStateFeatures

java.util.List<StateFeature> getStateFeatures(State s)

Returns non-zero state features for a given state. This method should be implemented if it is to be used with algorithms that compute V-values from state features or other values that are independent of the actions.

Parameters:

s - the state for which features should be returned

Returns:

the features for state s

getActionFeaturesSets

java.util.List<ActionFeaturesQuery> getActionFeaturesSets(State s,
                                                        java.util.List<GroundedAction> actions)

Returns non-zero action features for all of provided actions in state s. This method should be implemented if it is to be used with algorithms that compute Q-values from action features or other values are the dependent on the actions. Note that features for different actions should return different feature ids.

Parameters:

s - the state for which features should be returned

actions - the action set for which the action features should be returned

Returns:

returns the set set of action features for each action in actions

freezeDatabaseState

void freezeDatabaseState(boolean toggle)

Enable or disable the database from generating new features. This method only needs to do anything if it creates features in an online fashion. That is, if the set of possible state features is defined at construction, then this method does not need to do anything. If features are generated as needed, such as with an instance-based feature set, then when the database is told to be frozen no new instances should be created.

Parameters:

toggle -

numberOfFeatures

int numberOfFeatures()

Returns the number of features this database tracks.

Returns:

the number of features this database tracks.

copy

FeatureDatabase copy()

Returns a deep copy of this feature database. If the feature database is dynamic, then changes to one will not affect the other.

Returns:

a deep copy of this feature database