xal.tools.statistics

Class MutableUnivariateStatistics

java.lang.Object

xal.tools.statistics.UnivariateStatistics

xal.tools.statistics.MutableUnivariateStatistics

public class MutableUnivariateStatistics
extends UnivariateStatistics

MutableUnivariateStatistics calculates statistics of a series of measurements. The statistics can be updated with each additional measurement. Only simple statistics are generated (mean and standard deviation).

Field Summary

Fields inherited from class xal.tools.statistics.UnivariateStatistics

_mean, _meanSquare, _population

Constructor Summary

Constructors

Constructor and Description
MutableUnivariateStatistics() Constructor with no samples.
MutableUnivariateStatistics(int size, double average, double averageSquare) Primary Constructor with a starting set of statistics.
MutableUnivariateStatistics(UnivariateStatistics stats) Copy constructor
MutableUnivariateStatistics(UnivariateStatistics stats, double scale) Constructor which scales the samples from an existing set of statistics.

Method Summary

Modifier and Type	Method and Description
void	addSample(double value) Add a new sample measurement.
void	addSamples(UnivariateStatistics stats) Merge in samples from other statistics.
void	clear() Clear the samples
void	removeSample(double value) Remove a sample from the statistics
void	replaceSample(double oldValue, double newValue) Replace an old sample with a fresh sample.
void	scaleData(double scale) Modify the statistics for data of another scale.

Methods inherited from class xal.tools.statistics.UnivariateStatistics

mean, meanSquare, population, sampleStandardDeviation, sampleStandardDeviationOfMean, sampleVariance, sampleVarianceOfMean, standardDeviation, standardDeviationOfMean, variance, varianceOfMean

Methods inherited from class java.lang.Object

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

Constructor Detail

MutableUnivariateStatistics

public MutableUnivariateStatistics()

Constructor with no samples.

MutableUnivariateStatistics

public MutableUnivariateStatistics(UnivariateStatistics stats)

Copy constructor

Parameters:

stats - the statistics to copy

MutableUnivariateStatistics

public MutableUnivariateStatistics(UnivariateStatistics stats,
                                   double scale)

Constructor which scales the samples from an existing set of statistics.

Parameters:

stats - the statistics against which to scale

scale - factor which is used to scale the copied statistics

MutableUnivariateStatistics

public MutableUnivariateStatistics(int size,
                                   double average,
                                   double averageSquare)

Primary Constructor with a starting set of statistics.

Parameters:

size - the number of samples

average - the mean

averageSquare - the mean square of the samples

Method Detail

clear

public void clear()

Clear the samples

addSample

public void addSample(double value)

Add a new sample measurement.

Parameters:

value - The new sample measurement

addSamples

public void addSamples(UnivariateStatistics stats)

Merge in samples from other statistics.

Parameters:

stats - the statistics which should be merged into these statistics

replaceSample

public void replaceSample(double oldValue,
                          double newValue)

Replace an old sample with a fresh sample. This is useful when updating statistics on circular buffers.

Parameters:

oldValue - the sample measurement to replace

newValue - the new sample measurement

removeSample

public void removeSample(double value)

Remove a sample from the statistics

Parameters:

value - the sample measurement to remove

scaleData

public void scaleData(double scale)

Modify the statistics for data of another scale. For example, if you took data with one set of units but want results in another. This method should be used with caution as it changes the scale of the data and new data should only be added if it uses the new scale.

Parameters:

scale - the amount by which to scale the existing sample measurements