Isis::Statistics Class Reference

This class is used to accumulate statistics on double arrays. More...

#include <Statistics.h>

Inherited by Isis::GaussianDistribution, Isis::GaussianStretch, and Isis::Histogram.

List of all members.

Public Member Functions
	Statistics ()
	Constructs an IsisStats object with accumulators and counters set to zero.
virtual	~Statistics ()
	Destroys the IsisStats object.
void	Reset ()
	Reset all accumulators and counters to zero.
void	AddData (const double *data, const unsigned int count)
	Add an array of doubles to the accumulators and counters.
void	AddData (const double data)
	Add a double to the accumulators and counters.
void	RemoveData (const double *data, const unsigned int count)
	Remove an array of doubles from the accumulators and counters.
void	RemoveData (const double data)
virtual void	SetValidRange (const double minimum=Isis::ValidMinimum, const double maximum=Isis::ValidMaximum)
double	ValidMinimum () const
double	ValidMaximum () const
bool	InRange (const double value)
bool	AboveRange (const double value)
bool	BelowRange (const double value)
double	Average () const
	Computes and returns the average.
double	StandardDeviation () const
	Computes and returns the standard deviation.
double	Variance () const
	Computes and returns the variance.
double	Rms () const
	Computes and returns the rms.
double	Minimum () const
	Returns the absolute minimum double found in all data passed through the AddData method.
double	Maximum () const
	Returns the absolute maximum double found in all data passed through the AddData method.
double	ChebyshevMinimum (const double percent=99.5) const
	This method returns a minimum such that X percent of the data will fall with K standard deviations of the average (Chebyshev's Theorem).
double	ChebyshevMaximum (const double percent=99.5) const
	This method returns a maximum such that X percent of the data will fall with K standard deviations of the average (Chebyshev's Theorem).
double	BestMinimum (const double percent=99.5) const
	This method returns the better of the absolute minimum or the Chebyshev minimum.
double	BestMaximum (const double percent=99.5) const
	This method returns the better of the absolute maximum or the Chebyshev maximum.
double	ZScore (const double value) const
	This method returns the better of the z-score of the given value.
BigInt	TotalPixels () const
	Returns the total number of pixels processed (valid and invalid).
BigInt	ValidPixels () const
	Returns the total number of valid pixels processed.
BigInt	OverRangePixels () const
	Returns the total number of pixels over the valid range encountered.
BigInt	UnderRangePixels () const
	Returns the total number of pixels under the valid range encountered.
BigInt	NullPixels () const
	Returns the total number of NULL pixels encountered.
BigInt	LisPixels () const
	Returns the total number of low instrument saturation (LIS) pixels encountered.
BigInt	LrsPixels () const
	Returns the total number of low representation saturation (LRS) pixels encountered.
BigInt	HisPixels () const
	Returns the total number of high instrument saturation (HIS) pixels encountered.
BigInt	HrsPixels () const
	Returns the total number of high representation saturation (HRS) pixels encountered.
BigInt	OutOfRangePixels () const
	Returns the total number of pixels outside of the valid range encountered.
double	Sum () const
	Returns the sum of all the data.
double	SumSquare () const
	Returns the sum of all the squared data.

---

Detailed Description

This class is used to accumulate statistics on double arrays.

This class is used to accumulate statistics on double arrays. In particular, it is highly useful for obtaining statistics on cube data. Parameters which can be computed are 1) average, 2) standard deviation, 3) variance, 4) minimum, 5) maximum and 6) various counts of valid and/or special pixels.

The following example shows a simple set up and usage of the Statistics class to calculate the average of a set of values:

   Statistics myStats ;
   double myData [] = { 1.0, 3.0, 2.4, 7.5 } ;

   myStats.AddData (myData, 4) ;
   double myAverage = myStats.Average () ;
   cout << "The average of the data is " << myAverage << endl ;

For an example of how the Statistics object is used in Isis, see the Histogram object (inherits from Statistics) and the stats application, stats.cpp (uses the Statistics child class Histogram).

Author:

2002-05-06 Jeff Anderson

---

Constructor & Destructor Documentation

Isis::Statistics::Statistics

(

)

Constructs an IsisStats object with accumulators and counters set to zero.

Isis::Statistics::~Statistics

(

)

[virtual]

Destroys the IsisStats object.

---

Member Function Documentation

bool Isis::Statistics::AboveRange

(

const double

value

)

[inline]

Referenced by AddData().

void Isis::Statistics::AddData	(	const double *	data,
		const unsigned int	count
	)

Add an array of doubles to the accumulators and counters.

This method can be invoked multiple times (for example: once for each line in a cube) before obtaining statistics.

Parameters:

data	The data to be added to the data set used for statistical calculations.
count	The number of elements in the incoming data to be added.

Reimplemented in Isis::Histogram.

Referenced by Isis::MultivariateStatistics::AddData(), Isis::CameraStatistics::addStats(), Isis::HiEqualization::HiCalculateFunctor::addStats(), Isis::Process::CalculateStatistics(), Isis::IndependentCubeViewport::cubeDataChanged(), Isis::ControlPoint::GetLineResidualRms(), Isis::ControlPoint::GetResidualRms(), Isis::ControlPoint::GetSampleResidualRms(), Isis::ControlPoint::GetStatistic(), Isis::StandardDeviationOperator::Interest(), Isis::ControlPointGraphicsItem::paint(), Isis::AutoReg::Reduce(), Isis::ReseauDistortionMap::SetFocalPlane(), Isis::VisualDisplay::setPixelData(), Isis::ReseauDistortionMap::SetUndistortedFocalPlane(), Isis::Chip::Statistics(), Isis::Cube::statistics(), and Isis::StretchTool::statsFromCube().

void Isis::Statistics::AddData

(

const double

data

)

[inline]

Add a double to the accumulators and counters.

This method can be invoked multiple times (for example: once for each pixel in a cube) before obtaining statistics.

Parameters:

data	The data to be added to the data set used for statistical calculations.

Reimplemented in Isis::Histogram.

References AboveRange(), InRange(), Isis::IsHisPixel(), Isis::IsHrsPixel(), Isis::IsLisPixel(), Isis::IsLrsPixel(), Isis::IsNullPixel(), and Isis::IsValidPixel().

double Isis::Statistics::Average

(

)

const

Computes and returns the average.

If there are no valid pixels, then NULL8 is returned.

Returns:

The Average

References Isis::NULL8.

Referenced by Isis::OverlapNormalization::AddOverlap(), Isis::ControlNet::AverageResidual(), Isis::MultivariateStatistics::Covariance(), Isis::ControlPointGraphicsItem::paint(), Isis::VisualDisplay::paintPixmap(), Isis::AutoReg::Reduce(), Isis::HistogramTool::refreshPlot(), and Isis::CameraStatistics::toPvl().

bool Isis::Statistics::BelowRange

(

const double

value

)

[inline]

double Isis::Statistics::BestMaximum

(

const double

percent = 99.5

)

const

This method returns the better of the absolute maximum or the Chebyshev maximum.

The better value is considered the value closest to the mean.

Parameters:

percent

The probability that the maximum is within K standard deviations of the mean (Used to compute the Chebyshev maximum). Default value = 99.5.

Returns:

Best of absolute and Chebyshev maximums

See also:

Statistics::Maximum Statistics::ChebyshevMaximum

References Isis::NULL8.

Referenced by Isis::IndependentCubeViewport::cubeDataChanged(), Isis::StretchTool::histFromBuffer(), Isis::VisualDisplay::setPixelData(), Isis::LinearStretchType::setStretch(), Isis::StretchTool::stretchBand(), and Isis::StretchTool::stretchBuffer().

double Isis::Statistics::BestMinimum

(

const double

percent = 99.5

)

const

This method returns the better of the absolute minimum or the Chebyshev minimum.

The better value is considered the value closest to the mean.

Parameters:

percent

The probability that the minimum is within K standard deviations of the mean (Used to compute the Chebyshev minimum). Default value = 99.5.

Returns:

Best of absolute and Chebyshev minimums

See also:

Statistics::Minimum Statistics::ChebyshevMinimum

References min(), and Isis::NULL8.

Referenced by Isis::IndependentCubeViewport::cubeDataChanged(), Isis::StretchTool::histFromBuffer(), Isis::VisualDisplay::setPixelData(), Isis::LinearStretchType::setStretch(), Isis::StretchTool::stretchBand(), and Isis::StretchTool::stretchBuffer().

double Isis::Statistics::ChebyshevMaximum

(

const double

percent = 99.5

)

const

This method returns a maximum such that X percent of the data will fall with K standard deviations of the average (Chebyshev's Theorem).

It can be used to obtain a minimum that does not include statistical outliers.

Parameters:

percent

The probability that the maximum is within K standard deviations of the mean. Default value = 99.5.

Returns:

maximum value excluding statistical outliers

Exceptions:

Isis::IException::Message

References _FILEINFO_, and Isis::NULL8.

double Isis::Statistics::ChebyshevMinimum

(

const double

percent = 99.5

)

const

This method returns a minimum such that X percent of the data will fall with K standard deviations of the average (Chebyshev's Theorem).

It can be used to obtain a minimum that does not include statistical outliers.

Parameters:

percent

The probability that the minimum is within K standard deviations of the mean. Default value = 99.5.

Returns:

Minimum value (excluding statistical outliers)

Exceptions:

Isis::IException::Message

References _FILEINFO_, and Isis::NULL8.

BigInt Isis::Statistics::HisPixels

(

)

const

Returns the total number of high instrument saturation (HIS) pixels encountered.

Returns:

The number of HIS pixels (data) processed

BigInt Isis::Statistics::HrsPixels

(

)

const

Returns the total number of high representation saturation (HRS) pixels encountered.

Returns:

The number of HRS pixels (data) processed

bool Isis::Statistics::InRange

(

const double

value

)

[inline]

Referenced by AddData().

BigInt Isis::Statistics::LisPixels

(

)

const

Returns the total number of low instrument saturation (LIS) pixels encountered.

Returns:

The number of LIS pixels (data) processed

BigInt Isis::Statistics::LrsPixels

(

)

const

Returns the total number of low representation saturation (LRS) pixels encountered.

Returns:

The number of LRS pixels (data) processed

double Isis::Statistics::Maximum

(

)

const

Returns the absolute maximum double found in all data passed through the AddData method.

If there are no valid pixels, then NULL8 is returned.

Returns:

Current maximum value in data set

Exceptions:

Isis::IException::Message

The data set is blank, so the maximum is invalid.

References _FILEINFO_, and Isis::NULL8.

Referenced by Isis::IndependentCubeViewport::cubeDataChanged(), Isis::QnetPointJigsawErrorFilter::filter(), Isis::QnetPointRegistrationErrorFilter::filter(), Isis::GaussianStretch::GaussianStretch(), Isis::ControlNet::GetMaximumResidual(), Isis::ControlPointGraphicsItem::paint(), Isis::VisualDisplay::paintPixmap(), Isis::HistogramTool::refreshPlot(), Isis::SawtoothStretchType::SawtoothStretchType(), Isis::ScatterPlotData::ScatterPlotData(), Isis::HistogramWidget::setHistogram(), Isis::BinaryStretchType::setStretch(), Isis::StretchTool::stretchBuffer(), and Isis::CameraStatistics::toPvl().

double Isis::Statistics::Minimum

(

)

const

Returns the absolute minimum double found in all data passed through the AddData method.

If there are no valid pixels, then NULL8 is returned.

Returns:

Current minimum value in data set.

Exceptions:

Isis::IException::Message

The data set is blank, so the minimum is invalid.

References _FILEINFO_, and Isis::NULL8.

Referenced by Isis::IndependentCubeViewport::cubeDataChanged(), Isis::GaussianStretch::GaussianStretch(), Isis::VisualDisplay::paintPixmap(), Isis::HistogramTool::refreshPlot(), Isis::SawtoothStretchType::SawtoothStretchType(), Isis::ScatterPlotData::ScatterPlotData(), Isis::HistogramWidget::setHistogram(), Isis::BinaryStretchType::setStretch(), Isis::StretchTool::stretchBuffer(), and Isis::CameraStatistics::toPvl().

BigInt Isis::Statistics::NullPixels

(

)

const

Returns the total number of NULL pixels encountered.

Returns:

The number of NULL pixels (data) processed

BigInt Isis::Statistics::OutOfRangePixels

(

)

const

Returns the total number of pixels outside of the valid range encountered.

Returns:

The number of Out of Range pixels (data) processed

BigInt Isis::Statistics::OverRangePixels

(

)

const

Returns the total number of pixels over the valid range encountered.

Returns:

The number of pixels less than the ValidMaximum() processed

void Isis::Statistics::RemoveData	(	const double *	data,
		const unsigned int	count
	)

Remove an array of doubles from the accumulators and counters.

Note that is invalidates the absolute minimum and maximum. They will no longer be usable.

Parameters:

data	The data to be removed from data set used for statistical calculations.
count	The number of elements in the data to be removed.

Exceptions:

Isis::IException::Message

RemoveData is trying to remove data that doesn't exist.

Reimplemented in Isis::Histogram.

References _FILEINFO_, Isis::IsHisPixel(), Isis::IsHrsPixel(), Isis::IsLisPixel(), Isis::IsLrsPixel(), Isis::IsNullPixel(), and Isis::IsValidPixel().

Referenced by Isis::MultivariateStatistics::RemoveData().

void Isis::Statistics::RemoveData

(

const double

data

)

void Isis::Statistics::Reset

(

)

Reset all accumulators and counters to zero.

Reimplemented in Isis::Histogram.

Referenced by Isis::AutoReg::Reduce(), Isis::MultivariateStatistics::Reset(), Isis::VisualDisplay::setLines(), Isis::VisualDisplay::setPixelData(), and Isis::VisualDisplay::setSamples().

double Isis::Statistics::Rms

(

)

const

Computes and returns the rms.

If there are no valid pixels, then NULL8 is returned.

Returns:

The rms (root mean square)

References Isis::NULL8.

Referenced by Isis::ControlPoint::GetLineResidualRms(), Isis::ControlPoint::GetResidualRms(), and Isis::ControlPoint::GetSampleResidualRms().

void Isis::Statistics::SetValidRange	(	const double	minimum = Isis::ValidMinimum,
		const double	maximum = Isis::ValidMaximum
	)		[virtual]

Reimplemented in Isis::Histogram.

References _FILEINFO_.

Referenced by Isis::StandardDeviationOperator::Interest(), Isis::Histogram::SetValidRange(), Isis::Chip::Statistics(), and Isis::Cube::statistics().

double Isis::Statistics::StandardDeviation

(

)

const

Computes and returns the standard deviation.

If there are no valid pixels, then NULL8 is returned.

Returns:

The standard deviation

Reimplemented in Isis::GaussianDistribution.

References Isis::NULL8.

Referenced by Isis::MultivariateStatistics::Correlation(), Isis::StandardDeviationOperator::Interest(), Isis::VisualDisplay::paintPixmap(), Isis::HistogramTool::refreshPlot(), Isis::ReseauDistortionMap::SetFocalPlane(), Isis::ReseauDistortionMap::SetUndistortedFocalPlane(), and Isis::CameraStatistics::toPvl().

double Isis::Statistics::Sum

(

)

const [inline]

Returns the sum of all the data.

Returns:

The sum of the data

Referenced by Isis::MultivariateStatistics::Covariance(), and Isis::MultivariateStatistics::LinearRegression().

double Isis::Statistics::SumSquare

(

)

const [inline]

Returns the sum of all the squared data.

Returns:

The sum of the squared data

Referenced by Isis::MultivariateStatistics::LinearRegression().

BigInt Isis::Statistics::TotalPixels

(

)

const

Returns the total number of pixels processed (valid and invalid).

Returns:

The number of pixels (data) processed

Referenced by Isis::VisualDisplay::paintPixmap().

BigInt Isis::Statistics::UnderRangePixels

(

)

const

Returns the total number of pixels under the valid range encountered.

Returns:

The number of pixels less than the ValidMinimum() processed

double Isis::Statistics::ValidMaximum

(

)

const [inline]

double Isis::Statistics::ValidMinimum

(

)

const [inline]

BigInt Isis::Statistics::ValidPixels

(

)

const

Returns the total number of valid pixels processed.

Only valid pixels are utilized when computing the average, standard deviation, variance, minimum and maximum.

Returns:

The number of valid pixels (data) processed

Referenced by Isis::OverlapNormalization::AddOverlap(), Isis::IndependentCubeViewport::cubeDataChanged(), Isis::QHistogram::Load(), Isis::HistogramTool::refreshPlot(), Isis::StretchTool::stretchBuffer(), and Isis::StretchTool::updateHistograms().

double Isis::Statistics::Variance

(

)

const

Computes and returns the variance.

If there are no valid pixels, then NULL8 is returned.

Returns:

The variance

References Isis::NULL8.

Referenced by Isis::HistogramTool::refreshPlot().

double Isis::Statistics::ZScore

(

const double

value

)

const

This method returns the better of the z-score of the given value.

The z-score is the number of standard deviations the value lies above or below the average.

Parameters:

value

The value to calculate the z-score of.

Returns:

z-score

References _FILEINFO_.

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The documentation for this class was generated from the following files:

• src/base/objs/Statistics/Statistics.h
• src/base/objs/Statistics/Statistics.cpp