aima.core.search.online

Class OnlineSearchProblem

java.lang.Object

aima.core.search.online.OnlineSearchProblem

public class OnlineSearchProblem
extends java.lang.Object

Artificial Intelligence A Modern Approach (3rd Edition): page 147.

An online search problem must be solved by an agent executing actions, rather than by pure computation. We assume a deterministic and fully observable environment (Chapter 17 relaxes these assumptions), but we stipulate that the agent knows only the following:

• ACTIONS(s), which returns a list of actions allowed in state s;
• The step-cost function c(s, a, s') - note that this cannot be used until the agent knows that s' is the outcome; and
• GOAL-TEST(s).

Author:

Ciaran O'Reilly, Mike Stampone

Field Summary

Fields

Modifier and Type	Field and Description
protected ActionsFunction	actionsFunction
protected GoalTest	goalTest
protected StepCostFunction	stepCostFunction

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	OnlineSearchProblem()
	OnlineSearchProblem(ActionsFunction actionsFunction, GoalTest goalTest) Constructs an online search problem with the specified action function, goal test, and a default step cost function.
	OnlineSearchProblem(ActionsFunction actionsFunction, GoalTest goalTest, StepCostFunction stepCostFunction) Constructs an online search problem with the specified action function, goal test, and a default step cost function.

Method Summary

Modifier and Type	Method and Description
ActionsFunction	getActionsFunction() Returns the action function of this online search problem.
StepCostFunction	getStepCostFunction() Returns the step cost function of this online search problem.
boolean	isGoalState(java.lang.Object state) Returns true if the given state is a goal state.

Methods inherited from class java.lang.Object

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

Field Detail

actionsFunction

protected ActionsFunction actionsFunction

stepCostFunction

protected StepCostFunction stepCostFunction

goalTest

protected GoalTest goalTest

Constructor Detail

OnlineSearchProblem

public OnlineSearchProblem(ActionsFunction actionsFunction,
                           GoalTest goalTest)

Constructs an online search problem with the specified action function, goal test, and a default step cost function.

Parameters:

actionsFunction - ACTIONS(s), which returns a list of actions allowed in state s

goalTest - GOAL-TEST(s), which the agent can apply to a single state description to determine if it is a goal state

OnlineSearchProblem

public OnlineSearchProblem(ActionsFunction actionsFunction,
                           GoalTest goalTest,
                           StepCostFunction stepCostFunction)

Constructs an online search problem with the specified action function, goal test, and a default step cost function.

Parameters:

actionsFunction - ACTIONS(s), which returns a list of actions allowed in state s

goalTest - GOAL-TEST(s), which the agent can apply to a single state description to determine if it is a goal state

stepCostFunction - the step-cost function c(s, a, s') - note that this cannot be used until the agent knows that s' is the outcome

OnlineSearchProblem

protected OnlineSearchProblem()

Method Detail

getActionsFunction

public ActionsFunction getActionsFunction()

Returns the action function of this online search problem.

Returns:

the action function of this online search problem.

isGoalState

public boolean isGoalState(java.lang.Object state)

Returns true if the given state is a goal state.

Parameters:

state - an object representing a state

Returns:

true if the given state is a goal state.

getStepCostFunction

public StepCostFunction getStepCostFunction()

Returns the step cost function of this online search problem.

Returns:

the step cost function of this online search problem.