uk.ac.liv.util
Class CummulativeDistribution

java.lang.Object
  uk.ac.liv.util.CummulativeDistribution

All Implemented Interfaces:

java.lang.Cloneable, Distribution, Resetable, java.io.Serializable

Direct Known Subclasses:

HeavyweightDistribution

public class CummulativeDistribution

extends java.lang.Object

implements java.io.Serializable, java.lang.Cloneable, Resetable, Distribution

A utility class for cummulative tracking of stats for a series of doubles. Moments are incremented dynamically, rather than keeping the actual cases in memory.

Example usage:

CummulativeStatCounter series1 = new CummulativeStatCounter("series1");
series1.newData(4.5);
series1.newData(5.6);
series1.newData(9.0);
System.out.println("Standard deviation of series1 = " + series1.getStdDev());
series1.newData(5.56);
series1.newData(12);
System.out.println("And now the standard deviation = " + series1.getStdDev());


Version:

$Revision: 1.2 $

Author:

Steve Phelps

See Also:

Serialized Form

Field Summary

protected double	max The maximum so far.
protected double	min The minimum so far.
protected int	n The number of data in the series so far.
protected double	total The cummulative total of all numbers in the series so far.
protected double	totalSq The square of the total.
protected java.lang.String	varName The name of this series.

Constructor Summary

CummulativeDistribution()

CummulativeDistribution(java.lang.String varName)

Method Summary

java.lang.Object	clone()
double	getMax() Get the maximum datum.
double	getMean() Get the mean of the data.
double	getMin() Get the minimum datum.
int	getN() Get the number of items in the series.
java.lang.String	getName()
double	getStdDev() Get the standard deviation from the mean.
double	getStdDev(double origin) Get the standard deviation of the data about origin.
double	getTotal() Get the total of the data
double	getTrimmedMean(double p)
double	getVarCoef(double origin) Get the coefficient of variable about origin.
double	getVariance() Get the variance about the mean.
double	getVariance(double origin) Get the variance of the data about origin.
void	initialise()
void	log()
void	newData(double i) Add a new datum to the series.
void	reset() Reinitialise our state to the original settings.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

n

protected int n

The number of data in the series so far.

total

protected double total

The cummulative total of all numbers in the series so far.

totalSq

protected double totalSq

The square of the total.

min

protected double min

The minimum so far.

max

protected double max

The maximum so far.

varName

protected java.lang.String varName

The name of this series.

Constructor Detail

CummulativeDistribution

public CummulativeDistribution(java.lang.String varName)

CummulativeDistribution

public CummulativeDistribution()

Method Detail

initialise

public void initialise()

newData

public void newData(double i)

Add a new datum to the series.

Specified by:

newData in interface Distribution

getN

public int getN()

Get the number of items in the series.

Specified by:

getN in interface Distribution

getMean

public double getMean()

Get the mean of the data.

Specified by:

getMean in interface Distribution

getVariance

public double getVariance(double origin)

Get the variance of the data about origin.

Specified by:

getVariance in interface Distribution

getStdDev

public double getStdDev(double origin)

Get the standard deviation of the data about origin.

Specified by:

getStdDev in interface Distribution

getVariance

public double getVariance()

Get the variance about the mean.

Specified by:

getVariance in interface Distribution

getStdDev

public double getStdDev()

Get the standard deviation from the mean.

Specified by:

getStdDev in interface Distribution

getVarCoef

public double getVarCoef(double origin)

Get the coefficient of variable about origin.

Specified by:

getVarCoef in interface Distribution

getMin

public double getMin()

Get the minimum datum.

Specified by:

getMin in interface Distribution

getMax

public double getMax()

Get the maximum datum.

Specified by:

getMax in interface Distribution

getTotal

public double getTotal()

Get the total of the data

Specified by:

getTotal in interface Distribution

clone

public java.lang.Object clone()
                       throws java.lang.CloneNotSupportedException

Throws:

java.lang.CloneNotSupportedException

reset

public void reset()

Description copied from interface: Resetable

Reinitialise our state to the original settings.

Specified by:

reset in interface Resetable

getName

public java.lang.String getName()

Specified by:

getName in interface Distribution

toString

public java.lang.String toString()

log

public void log()

Specified by:

log in interface Distribution

getTrimmedMean

public double getTrimmedMean(double p)

Specified by:

getTrimmedMean in interface Distribution