aima.core.util

Class FrequencyCounter<T>

java.lang.Object

aima.core.util.FrequencyCounter<T>

public class FrequencyCounter<T>
extends java.lang.Object

A utility class for keeping counts of objects. Will return 0 for any object for which it has not recorded a count against.

Author:

Ravi Mohan, Mike Stampone

Constructor Summary

Constructors

Constructor and Description
FrequencyCounter() Default Constructor.

Method Summary

Modifier and Type	Method and Description
void	clear() Remove all the currently recorded frequency counts.
java.lang.Integer	getCount(T key) Returns the count to which the specified key is mapped in this frequency counter, or 0 if the map contains no mapping for this key.
java.util.Set<T>	getStates()
void	incrementFor(T key) Increments the count to which the specified key is mapped in this frequency counter, or puts 1 if the map contains no mapping for this key.
double	probabilityOf(T key) Returns the count to which the specified key is mapped in this frequency counter, divided by the total of all counts.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

FrequencyCounter

public FrequencyCounter()

Default Constructor.

Method Detail

getCount

public java.lang.Integer getCount(T key)

Returns the count to which the specified key is mapped in this frequency counter, or 0 if the map contains no mapping for this key.

Parameters:

key - the key whose associated count is to be returned.

Returns:

the count to which this map maps the specified key, or 0 if the map contains no mapping for this key.

incrementFor

public void incrementFor(T key)

Increments the count to which the specified key is mapped in this frequency counter, or puts 1 if the map contains no mapping for this key.

Parameters:

key - the key whose associated count is to be returned.

probabilityOf

public double probabilityOf(T key)

Returns the count to which the specified key is mapped in this frequency counter, divided by the total of all counts.

Parameters:

key - the key whose associated count is to be divided.

Returns:

the count to which this map maps the specified key, divided by the total count.

getStates

public java.util.Set<T> getStates()

Returns:

a set of objects for which frequency counts have been recorded.

clear

public void clear()

Remove all the currently recorded frequency counts.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object