burlap.behavior.policy

Class RandomPolicy

java.lang.Object

burlap.behavior.policy.Policy

burlap.behavior.policy.RandomPolicy

public class RandomPolicy
extends Policy

A uniform random policy for single agent domains. You may set the actions between which it randomly selects by providing a domain (from which the domains primitive actions are copied into an internal list) or from a list of Action objects (from which the action references are copied into an internal list). You may also add additional actions with the addAction(burlap.oomdp.singleagent.Action) method or remove or clear the actions.
Upon action selection, all applicable grounded actions for the state are generated and an action is selected uniformly randomly from them. The policy is not defined if there are no applicable actions.

Nested Class Summary

Nested classes/interfaces inherited from class burlap.behavior.policy.Policy

Policy.ActionProb, Policy.GroundedAnnotatedAction, Policy.PolicyUndefinedException

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.List<Action>	actions The actions from which selection is performed
protected java.util.Random	rand The random factory used to randomly select actions.

Fields inherited from class burlap.behavior.policy.Policy

annotateOptionDecomposition, evaluateDecomposesOptions

Constructor Summary

Constructors

Constructor and Description
RandomPolicy(Domain domain) Initializes by copying all the primitive actions references defined for the domain into an internal action list for this policy.
RandomPolicy(java.util.List<Action> acitons) Initializes by copying all the actions references defined in the provided list into an internal action list for this policy.

Method Summary

Methods

Modifier and Type	Method and Description
void	addAction(Action action) Adds an aciton to consider in selection.
void	clearActions() Clears the action list used in action selection.
AbstractGroundedAction	getAction(State s) This method will return an action sampled by the policy for the given state.
java.util.List<Policy.ActionProb>	getActionDistributionForState(State s) This method will return action probability distribution defined by the policy.
java.util.Random	getRandomGenerator() Returns the random generator used for action selection.
java.util.List<Action>	getSelectionActions() Returns of the list of actions that can be randomly selected.
boolean	isDefinedFor(State s) Specifies whether this policy is defined for the input state.
boolean	isStochastic() Indicates whether the policy is stochastic or deterministic.
void	removeAction(java.lang.String actionName) Removes an action from consideration.
void	setRandomGenerator(java.util.Random rand) Sets the random generator used for action selection.

Methods inherited from class burlap.behavior.policy.Policy

evaluateBehavior, evaluateBehavior, evaluateBehavior, evaluateBehavior, evaluateBehavior, evaluateMethodsShouldAnnotateOptionDecomposition, evaluateMethodsShouldDecomposeOption, followAndRecordPolicy, followAndRecordPolicy, getDeterministicPolicy, getProbOfAction, getProbOfActionGivenDistribution, getProbOfActionGivenDistribution, sampleFromActionDistribution

Methods inherited from class java.lang.Object

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

Field Detail

actions

protected java.util.List<Action> actions

The actions from which selection is performed

rand

protected java.util.Random rand

The random factory used to randomly select actions.

Constructor Detail

RandomPolicy

public RandomPolicy(Domain domain)

Initializes by copying all the primitive actions references defined for the domain into an internal action list for this policy.

Parameters:

domain - the domain containing all the primitive actions.

RandomPolicy

public RandomPolicy(java.util.List<Action> acitons)

Initializes by copying all the actions references defined in the provided list into an internal action list for this policy.

Parameters:

acitons - the actions to select between.

Method Detail

addAction

public void addAction(Action action)

Adds an aciton to consider in selection.

Parameters:

action - an action to consider in selection

clearActions

public void clearActions()

Clears the action list used in action selection. Note that if no actions are added to this policy after calling this method then the policy will be undefined everywhere.

removeAction

public void removeAction(java.lang.String actionName)

Removes an action from consideration.

Parameters:

actionName - the name of the action to remove.

getSelectionActions

public java.util.List<Action> getSelectionActions()

Returns of the list of actions that can be randomly selected.

Returns:

the list of actions that can be randomly selected.

getRandomGenerator

public java.util.Random getRandomGenerator()

Returns the random generator used for action selection.

Returns:

the random generator used for action selection.

setRandomGenerator

public void setRandomGenerator(java.util.Random rand)

Sets the random generator used for action selection.

Parameters:

rand - the random generator used for action selection.

getAction

public AbstractGroundedAction getAction(State s)

Description copied from class: Policy

This method will return an action sampled by the policy for the given state. If the defined policy is stochastic, then multiple calls to this method for the same state may return different actions. The sampling should be with respect to defined action distribution that is returned by getActionDistributionForState

Specified by:

getAction in class Policy

Parameters:

s - the state for which an action should be returned

Returns:

a sample action from the action distribution; null if the policy is undefined for s

getActionDistributionForState

public java.util.List<Policy.ActionProb> getActionDistributionForState(State s)

Description copied from class: Policy

This method will return action probability distribution defined by the policy. The action distribution is represented by a list of ActionProb objects, each which specifies a grounded action and a probability of that grounded action being taken. The returned list does not have to include actions with probability 0.

Specified by:

getActionDistributionForState in class Policy

Parameters:

s - the state for which an action distribution should be returned

Returns:

a list of possible actions taken by the policy and their probability.

isStochastic

public boolean isStochastic()

Description copied from class: Policy

Indicates whether the policy is stochastic or deterministic.

Specified by:

isStochastic in class Policy

Returns:

true when the policy is stochastic; false when it is deterministic.

isDefinedFor

public boolean isDefinedFor(State s)

Description copied from class: Policy

Specifies whether this policy is defined for the input state.

Specified by:

isDefinedFor in class Policy

Parameters:

s - the input state to test for whether this policy is defined

Returns:

true if this policy is defined for State s, false otherwise.