org.apache.mahout.cf.taste.impl.common

Class FixedRunningAverage

java.lang.Object

org.apache.mahout.cf.taste.impl.common.FixedRunningAverage

All Implemented Interfaces:

Serializable, RunningAverage

Direct Known Subclasses:

FixedRunningAverageAndStdDev

public class FixedRunningAverage
extends Object
implements RunningAverage, Serializable

A simple class that represents a fixed value of an average and count. This is useful when an API needs to return RunningAverage but is not in a position to accept updates to it.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
FixedRunningAverage(double average, int count)

Method Summary

Modifier and Type	Method and Description
void	addDatum(double datum)
void	changeDatum(double delta)
double	getAverage()
int	getCount()
RunningAverage	inverse()
void	removeDatum(double datum)
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

FixedRunningAverage

public FixedRunningAverage(double average,
                           int count)

Method Detail

addDatum

public void addDatum(double datum)

Specified by:

addDatum in interface RunningAverage

Parameters:

datum - new item to add to the running average

Throws:

UnsupportedOperationException

removeDatum

public void removeDatum(double datum)

Specified by:

removeDatum in interface RunningAverage

Parameters:

datum - item to remove to the running average

Throws:

UnsupportedOperationException

changeDatum

public void changeDatum(double delta)

Specified by:

changeDatum in interface RunningAverage

Parameters:

delta - amount by which to change a datum in the running average

Throws:

UnsupportedOperationException

getCount

public int getCount()

Specified by:

getCount in interface RunningAverage

getAverage

public double getAverage()

Specified by:

getAverage in interface RunningAverage

inverse

public RunningAverage inverse()

Specified by:

inverse in interface RunningAverage

Returns:

a (possibly immutable) object whose average is the negative of this object's

toString

public String toString()

Overrides:

toString in class Object