cgl.narada.util
Class StatUtils

java.lang.Object
  cgl.narada.util.StatUtils

public class StatUtils
extends Object

This class implements some of the utilies commonly used during performance measurements on links and by other programs.

Constructor Summary

StatUtils()

Method Summary

static double	computeJitter(double jitter, double delayD, double delayDplusOne) Computes the jitter based on previous jitter, and current inter-packet arrival times.
static double	computeMean(long[] values, int numOfValues, int maxReject)
static double	computeMeanWithoutOutliers(long[] values, int numOfValues) This method computes the mean of a sample of values by first removing the outliers.
static double	computeStandardDeviation(long[] values, int numOfValues, int maxReject)
static double	computeStandardDeviationWithoutOutliers(long[] values, int numOfValues) This method computes the standard deviation within a sample of values by first removing the outliers.
static double	computeStandardErrorOfMean(double standardDeviation, int numOfSamples) This method computes the standard error of the mean based on the standard deviation and the num of samples in the original sample.
static long[]	getValuesWithoutOutliers(long[] values, int numOfValues) This method removes outliers from a sample of values.
static void	main(String[] args)

Methods inherited from class java.lang.Object

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

Constructor Detail

StatUtils

public StatUtils()

Method Detail

computeStandardErrorOfMean

public static double computeStandardErrorOfMean(double standardDeviation,
                                                int numOfSamples)

This method computes the standard error of the mean based on the standard deviation and the num of samples in the original sample. The standard error is the ratio of the standard deviation to the square root of the number of samples.

computeMean

public static double computeMean(long[] values,
                                 int numOfValues,
                                 int maxReject)

computeStandardDeviation

public static double computeStandardDeviation(long[] values,
                                              int numOfValues,
                                              int maxReject)

computeJitter

public static double computeJitter(double jitter,
                                   double delayD,
                                   double delayDplusOne)

Computes the jitter based on previous jitter, and current inter-packet arrival times.

computeStandardDeviationWithoutOutliers

public static double computeStandardDeviationWithoutOutliers(long[] values,
                                                             int numOfValues)

This method computes the standard deviation within a sample of values by first removing the outliers.

computeMeanWithoutOutliers

public static double computeMeanWithoutOutliers(long[] values,
                                                int numOfValues)

This method computes the mean of a sample of values by first removing the outliers.

getValuesWithoutOutliers

public static long[] getValuesWithoutOutliers(long[] values,
                                              int numOfValues)

This method removes outliers from a sample of values. The samples returned are the ones that do not contain the outliers. The size of the returned array MAY or MAY NOT be less than the original array.

main

public static void main(String[] args)