DGtal: DGtal::MultiStatistics Class Reference

Aim: This class stores a set of sample values for several variables and can then compute different statistics, like sample mean, sample variance, sample unbiased variance, etc. More...

#include <DGtal/math/MultiStatistics.h>

Public Member Functions
	~MultiStatistics ()

	MultiStatistics (const unsigned int size, const bool storeSamples=false)

unsigned int	nb () const

unsigned int	samples (const unsigned int k) const

double	mean (const unsigned int k) const

double	variance (const unsigned int k) const

double	unbiasedVariance (const unsigned int k) const

double	max (const unsigned int k) const

unsigned int	maxIndice (unsigned int k) const

double	min (const unsigned int k) const

unsigned int	minIndice (const unsigned int k) const

double	value (const unsigned int k, const unsigned int i) const

void	addValue (unsigned int k, double v)

template<class Iter >
void	addValues (const unsigned int k, Iter b, Iter e)

void	terminate ()

void	init (unsigned int size, bool storeSamples)

void	clear ()

void	erase ()

double	covariance (const unsigned int x, const unsigned int y, const unsigned int s=0, unsigned int e=0) const

std::pair< double, double >	linearRegression (const unsigned int x, const unsigned int y) const

double	median (const unsigned int k)

void	selfDisplay (std::ostream &out) const

bool	isValid () const

Static Public Member Functions
static void	read (std::istream &in, MultiStatistics &samples, const std::vector< unsigned int > &indices)

Protected Member Functions
	MultiStatistics ()

Private Member Functions
	MultiStatistics (const MultiStatistics &other)

MultiStatistics &	operator= (const MultiStatistics &other)

Private Attributes
unsigned int	myNb

unsigned int *	mySamples

double *	myExp

double *	myExp2

double *	myVar

double *	myUnbiasedVar

double *	myMax

unsigned int *	myIndiceMax

double *	myMin

unsigned int *	myIndiceMin

bool	myStoreSamples

std::vector< double > *	myValues

bool	myIsTerminate

Detailed Description

Aim: This class stores a set of sample values for several variables and can then compute different statistics, like sample mean, sample variance, sample unbiased variance, etc.

Description of class 'MultiStatistics'

Note: the method terminate() should be called before accessing to the quantities like mean, variance, etc.

The proposed implementation is mainly a backport from ImaGene with some various refactoring.

Definition at line 66 of file MultiStatistics.h.

Constructor & Destructor Documentation

◆ ~MultiStatistics()

DGtal::MultiStatistics::~MultiStatistics ( )

Destructor.

◆ MultiStatistics() [1/3]

DGtal::MultiStatistics::MultiStatistics	(	const unsigned int	size,
		const bool	storeSamples = `false`
	)

Creates an object for computing [size] statistics.

Parameters

[in]	size	the number of statistical variables.
[in]	storeSamples	when 'true', stores each given sample, default is 'false'

◆ MultiStatistics() [2/3]

DGtal::MultiStatistics::MultiStatistics ( )

protected

Constructor. Forbidden by default (protected to avoid g++ warnings).

◆ MultiStatistics() [3/3]

DGtal::MultiStatistics::MultiStatistics ( const MultiStatistics & other )

private

Copy constructor.

Parameters

other the object to clone. Forbidden by default.

Member Function Documentation

◆ addValue()

void DGtal::MultiStatistics::addValue	(	unsigned int	k,
		double	v
	)

Adds a new sample value [v] for the variable [k].

Parameters

[in]	k	the statistical variable.
[in]	v	the new sample value.

Referenced by TEST_CASE().

◆ addValues()

template<class Iter >

void DGtal::MultiStatistics::addValues	(	const unsigned int	k,
		Iter	b,
		Iter	e
	)

Adds a sequence of sample values for the variable [k], scanning a container from iterators [b] to [e].

Exemple:

vector<double> x;
MultiStatistics stats( 1, true );
stats.addValue( x + 4, x + 10 );

Parameters

[in]	k	the statistical variable.
[in]	b	an iterator on the starting point.
[in]	e	an iterator after the last point.

Referenced by TEST_CASE().

◆ clear()

void DGtal::MultiStatistics::clear ( )

Clears the object from all given samples. The object still represents 'nb()' statistical variables.

◆ covariance()

double DGtal::MultiStatistics::covariance	(	const unsigned int	x,
		const unsigned int	y,
		const unsigned int	s = `0`,
		unsigned int	e = `0`
	)		const

Computes the covariance of the [x],[y] variables. The 'MultiStatistics' object should have stored its values and 'terminate' should have been called.

Parameters

[in]	x	the index of the statistics to be used as the x-variable (should be valid)
[in]	y	the index of the statistics to be used as the y-variable (should be valid)
[in]	s	the starting value index (default is 0 )
[in]	e	the after-the-end value index (default is 0, meaning all )

Returns: the covariance of [x],[y] from indices [s] to [e].

◆ erase()

void DGtal::MultiStatistics::erase ( )

Erases the object as if it was just created. The user must call 'init()' before any other method.

See also: init

◆ init()

void DGtal::MultiStatistics::init	(	unsigned int	size,
		bool	storeSamples
	)

Reinitializes the object to contain [size] statistical variables. All preceding sample values and statistics are lost. Calls 'erase()'.

Parameters

[in]	size	the number of statistical variables.
[in]	storeSamples	when 'true', stores each given sample,

See also: erase

◆ isValid()

bool DGtal::MultiStatistics::isValid ( ) const

Checks the validity/consistency of the object.

Returns: 'true' if the object is valid, 'false' otherwise.

◆ linearRegression()

std::pair<double,double> DGtal::MultiStatistics::linearRegression	(	const unsigned int	x,
		const unsigned int	y
	)		const

Computes the linear regression of the ([x],[y]) variables. The 'MultiStatistics' object should have stored its values and 'terminate' should have been called.

Parameters

[in]	x	the index of the x-variable (should be valid )
[in]	y	the index of the y-variable (should be valid )

Returns: the pair (slope, shift at origin )

◆ max()

double DGtal::MultiStatistics::max ( const unsigned int k ) const

inline

Parameters

[in] k the statistical variable.

Returns: the maximal value for this variable.

Precondition: method 'terminate' must have been called.

See also: terminate

Referenced by TEST_CASE().

◆ maxIndice()

unsigned int DGtal::MultiStatistics::maxIndice ( unsigned int k ) const

inline

Parameters

[in] k the statistical variable.

Returns: the indice of the maximal value for this variable.

Precondition: method 'terminate' must have been called.

See also: terminate

◆ mean()

double DGtal::MultiStatistics::mean ( const unsigned int k ) const

inline

Parameters

[in] k the statistical variable.

Returns: the sample mean for this variable.

Precondition: method 'terminate' must have been called.

See also: terminate

Referenced by TEST_CASE().

◆ median()

double DGtal::MultiStatistics::median ( const unsigned int k )

Computes the median value for a variable k. The 'MultiStatistics' object should have stored its values and 'terminate' should have been called.

Parameters

[in] k the statistical variable.

Returns: the median value for the variable k.

Referenced by TEST_CASE().

◆ min()

double DGtal::MultiStatistics::min ( const unsigned int k ) const

inline

Parameters

[in] k the statistical variable.

Returns: the minimal value for this variable.

Precondition: method 'terminate' must have been called.

See also: terminate

Referenced by TEST_CASE().

◆ minIndice()

unsigned int DGtal::MultiStatistics::minIndice ( const unsigned int k ) const

inline

Parameters

[in] k the statistical variable.

Returns: the indice of the minimal value for this variable.

Precondition: method 'terminate' must have been called.

See also: terminate

◆ nb()

unsigned int DGtal::MultiStatistics::nb ( ) const

inline

Returns: the number of statistical variables.

◆ operator=()

MultiStatistics& DGtal::MultiStatistics::operator= ( const MultiStatistics & other )

private

Assignment.

Parameters

other the object to copy.

Returns: a reference on 'this'. Forbidden by default.

◆ read()

static void DGtal::MultiStatistics::read	(	std::istream &	in,
		MultiStatistics &	samples,
		const std::vector< unsigned int > &	indices
	)

static

Reads the input stream [in] line by line, excluding line beginning with '#' and selects some columns according to [indices] to fill the array of samples [samples]. For instance, if indices == { 3, 4, 1 }, then samples( 0 ) will contain the third column, samples( 1 ), the fourth column and samples( 2 ) the first column.

Parameters

[out]	in	(modified) the input stream.
[out]	samples	(updates) stores the data.
[in]	indices	specifies in which columns data are read.

◆ samples()

unsigned int DGtal::MultiStatistics::samples ( const unsigned int k ) const

inline

Parameters

[in] k the statistical variable.

Returns: the number of samples for this variable.

◆ selfDisplay()

void DGtal::MultiStatistics::selfDisplay ( std::ostream & out ) const

Writes/Displays the object on an output stream.

Parameters

[out] out the output stream where the object is written.

◆ terminate()

void DGtal::MultiStatistics::terminate ( )

Once all sample values have been added to this object, computes meaningful statistics like sample mean, variance and unbiased variance.

See also: mean, variance, unbiasedVariance, min, max

Referenced by TEST_CASE().

◆ unbiasedVariance()

double DGtal::MultiStatistics::unbiasedVariance ( const unsigned int k ) const

inline

Parameters

k	the statistical variable.

Returns: the unbiased sample variance for this variable.

Precondition: method 'terminate' must have been called.

See also: terminate

◆ value()

double DGtal::MultiStatistics::value	(	const unsigned int	k,
		const unsigned int	i
	)		const

inline

Returns a stored sample value that was added before. The object should have been initialized with 'store_samples = true'.

Parameters

[in]	k	the statistical variable.
[in]	i	the index of the sample value, '0<=i<samples(k)'.

Returns: the [i]-th value for this variable.

See also: MultiStatistics, init

◆ variance()

double DGtal::MultiStatistics::variance ( const unsigned int k ) const

inline

Parameters

[in] k the statistical variable.

Returns: the sample variance for this variable.

Precondition: method 'terminate' must have been called.

See also: terminate

Field Documentation

◆ myExp

double* DGtal::MultiStatistics::myExp

private

For each variable, stores the sum of sample values for computing sample mean.

Definition at line 354 of file MultiStatistics.h.

◆ myExp2

double* DGtal::MultiStatistics::myExp2

private

For each variable, stores the sum of squared sample values for computing sample variance.

Definition at line 360 of file MultiStatistics.h.

◆ myIndiceMax

unsigned int* DGtal::MultiStatistics::myIndiceMax

private

For each variable, stores the indice of the maximal sample value.

Definition at line 380 of file MultiStatistics.h.

◆ myIndiceMin

unsigned int* DGtal::MultiStatistics::myIndiceMin

private

For each variable, stores the indice of the minimal sample value.

Definition at line 390 of file MultiStatistics.h.

◆ myIsTerminate

bool DGtal::MultiStatistics::myIsTerminate

private

To prevent that terminate() is called before using statistics like mean, variance etc.

Definition at line 407 of file MultiStatistics.h.

◆ myMax

double* DGtal::MultiStatistics::myMax

private

For each variable, stores the maximal sample value.

Definition at line 375 of file MultiStatistics.h.

◆ myMin

double* DGtal::MultiStatistics::myMin

private

For each variable, stores the minimal sample value.

Definition at line 385 of file MultiStatistics.h.

◆ myNb

unsigned int DGtal::MultiStatistics::myNb

private

Number of statistical variables.

Definition at line 343 of file MultiStatistics.h.

◆ mySamples

unsigned int* DGtal::MultiStatistics::mySamples

private

For each variable, number of samples

Definition at line 348 of file MultiStatistics.h.

◆ myStoreSamples

bool DGtal::MultiStatistics::myStoreSamples

private

Tells if values must be stored or not.

Definition at line 395 of file MultiStatistics.h.

◆ myUnbiasedVar

double* DGtal::MultiStatistics::myUnbiasedVar

private

For each variable, stores the unbiased sample variance.

Definition at line 370 of file MultiStatistics.h.

◆ myValues

std::vector<double>* DGtal::MultiStatistics::myValues

private

For each variable, stores the sample values if [myStoreSamples] is 'true'.

Definition at line 401 of file MultiStatistics.h.

◆ myVar

double* DGtal::MultiStatistics::myVar

private

For each variable, stores the sample variance.

Definition at line 365 of file MultiStatistics.h.

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

MultiStatistics.h

Public Member Functions

Static Public Member Functions

Protected Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ ~MultiStatistics()

◆ MultiStatistics() [1/3]

◆ MultiStatistics() [2/3]

◆ MultiStatistics() [3/3]

Member Function Documentation

◆ addValue()

◆ addValues()

◆ clear()

◆ covariance()

◆ erase()

◆ init()

◆ isValid()

◆ linearRegression()

◆ max()

◆ maxIndice()

◆ mean()

◆ median()

◆ min()

◆ minIndice()

◆ nb()

◆ operator=()

◆ read()

◆ samples()

◆ selfDisplay()

◆ terminate()

◆ unbiasedVariance()

◆ value()

◆ variance()

Field Documentation

◆ myExp

◆ myExp2

◆ myIndiceMax

◆ myIndiceMin

◆ myIsTerminate

◆ myMax

◆ myMin

◆ myNb

◆ mySamples

◆ myStoreSamples

◆ myUnbiasedVar

◆ myValues

◆ myVar