burlap.behavior.policy

Interface Policy

All Known Subinterfaces:

EnumerablePolicy, SolverDerivedPolicy

All Known Implementing Classes:

Actor, ApprenticeshipLearning.StationaryRandomDistributionPolicy, BoltzmannActor, BoltzmannQPolicy, CachedPolicy, DDPlannerPolicy, ECorrelatedQJointPolicy, EGreedyJointPolicy, EGreedyMaxWellfare, EMinMaxPolicy, EpsilonGreedy, GreedyDeterministicQPolicy, GreedyQPolicy, JointPolicy, MAQSourcePolicy, PolicyFromJointPolicy, RandomPolicy, SDPlannerPolicy, UCTTreeWalkPolicy, UnmodeledFavoredPolicy

public interface Policy

An interface for defining a Policy. Requires providing an action mapping (or sampling in the case of stochastic policies) specifying the policy distribution, indicating whether the policy is stochastic, and checking if the policy is defined for an input state.

Various helper methods, including methods to rollout a policy from a model or in an environment are included in the PolicyUtils class.

Author:

James MacGlashan

Method Summary

Modifier and Type	Method and Description
Action	action(State s) This method will return an action sampled by the policy for the given state.
double	actionProb(State s, Action a) Returns the probability/probability density that the given action will be taken in the given state.
boolean	definedFor(State s) Specifies whether this policy is defined for the input state.

Method Detail

action

Action action(State s)

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

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

actionProb

double actionProb(State s,
                  Action a)

Returns the probability/probability density that the given action will be taken in the given state.

Parameters:

s - the state of interest

a - the action that may be taken in the state

Returns:

the probability/probability density

definedFor

boolean definedFor(State s)

Specifies whether this policy is defined for the input state.

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.