aima.core.logic.propositional.agent

Class KBAgent

java.lang.Object

aima.core.agent.impl.AbstractAgent

aima.core.logic.propositional.agent.KBAgent

All Implemented Interfaces:

Agent, EnvironmentObject

public abstract class KBAgent
extends AbstractAgent

Artificial Intelligence A Modern Approach (3rd Edition): Figure 7.1, page 236.

 function KB-AGENT(percept) returns an action
   persistent: KB, a knowledge base
               t, a counter, initially 0, indicating time
           
   TELL(KB, MAKE-PERCEPT-SENTENCE(percept, t))
   action <- ASK(KB, MAKE-ACTION-QUERY(t))
   TELL(KB, MAKE-ACTION-SENTENCE(action, t))
   t <- t + 1
   return action
 
 

Figure 7.1 A generic knowledge-based agent. Given a percept, the agent adds the percept to its knowledge base, asks the knowledge base for the best action, and tells the knowledge base that it has in fact taken that action.

Author:

Ciaran O'Reilly

Field Summary

Fields

Modifier and Type	Field and Description
protected KnowledgeBase	KB

Fields inherited from class aima.core.agent.impl.AbstractAgent

program

Constructor Summary

Constructors

Constructor and Description
KBAgent(KnowledgeBase KB)

Method Summary

Modifier and Type	Method and Description
abstract Action	ask(KnowledgeBase KB, Sentence actionQuery) A wrapper around the KB's ask() method which translates the action (in the form of a sentence) determined by the KB into an allowed 'Action' object from the current environment in which the KB-AGENT resides.
Action	execute(Percept percept) Call the Agent's program, which maps any given percept sequences to an action.
abstract Sentence	makeActionQuery(int t) MAKE-ACTION-QUERY constructs a sentence that asks what action should be done at the current time.
abstract Sentence	makeActionSentence(Action action, int t) MAKE-ACTION-SENTENCE constructs a sentence asserting that the chosen action was executed.
abstract Sentence	makePerceptSentence(Percept percept, int t) MAKE-PERCEPT-SENTENCE constructs a sentence asserting that the agent perceived the given percent at the given time.

Methods inherited from class aima.core.agent.impl.AbstractAgent

isAlive, setAlive

Methods inherited from class java.lang.Object

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

Field Detail

KB

protected KnowledgeBase KB

Constructor Detail

KBAgent

public KBAgent(KnowledgeBase KB)

Method Detail

execute

public Action execute(Percept percept)

Description copied from interface: Agent

Call the Agent's program, which maps any given percept sequences to an action.

Specified by:

execute in interface Agent

Overrides:

execute in class AbstractAgent

Parameters:

percept - The current percept of a sequence perceived by the Agent.

Returns:

the Action to be taken in response to the currently perceived percept.

makePerceptSentence

public abstract Sentence makePerceptSentence(Percept percept,
                                             int t)

MAKE-PERCEPT-SENTENCE constructs a sentence asserting that the agent perceived the given percent at the given time.

Parameters:

percept - the given percept

t - the given time

Returns:

a sentence asserting that the agent perceived the given percept at the given time.

makeActionQuery

public abstract Sentence makeActionQuery(int t)

MAKE-ACTION-QUERY constructs a sentence that asks what action should be done at the current time.

Parameters:

t - the current time.

Returns:

a sentence that asks what action should be done at the current time.

makeActionSentence

public abstract Sentence makeActionSentence(Action action,
                                            int t)

MAKE-ACTION-SENTENCE constructs a sentence asserting that the chosen action was executed.

Parameters:

action - the chose action.

t - the time at which the action was executed.

Returns:

a sentence asserting that the chosen action was executed.

ask

public abstract Action ask(KnowledgeBase KB,
                           Sentence actionQuery)

A wrapper around the KB's ask() method which translates the action (in the form of a sentence) determined by the KB into an allowed 'Action' object from the current environment in which the KB-AGENT resides.

Parameters:

KB - the KB to ask.

actionQuery - an action query.

Returns:

the Action to be performed in response to the given query.