DGtal::Statistic< TQuantity > Class Template Reference

Aim: This class processes a set of sample values for one variable and can then compute different statistics, like sample mean, sample variance, sample unbiased variance, etc. It is minimalistic for space efficiency. For multiple variables, sample storage and others, see Statistics class. More...

#include <DGtal/math/Statistic.h>

Public Types
typedef TQuantity	Quantity
typedef std::vector< Quantity >	Container
typedef Container::const_iterator	ConstIterator

Public Member Functions
	BOOST_CONCEPT_ASSERT ((concepts::CCommutativeRing< Quantity >))
	~Statistic ()
	Statistic (bool storeSample=false)
	Statistic (const Statistic &other)
Statistic &	operator= (const Statistic &other)
Statistic &	operator+= (const Statistic &other)
Statistic	operator+ (const Statistic &other) const
ConstIterator	begin () const
ConstIterator	end () const
unsigned int	samples () const
unsigned int	size () const
double	mean () const
double	variance () const
double	unbiasedVariance () const
Quantity	max () const
Quantity	min () const
Quantity	median ()
Quantity	operator[] (unsigned int i) const
void	addValue (Quantity v)
template<class Iter >
void	addValues (Iter b, Iter e)
void	clear ()
void	terminate ()
void	selfDisplay (std::ostream &that_stream) const
bool	OK () const

Private Attributes
unsigned int	mySamples
Quantity	myExp
Quantity	myExp2
Quantity	myMax
Quantity	myMin
Quantity	myMedian
Container	myValues
bool	myStoreSamples
bool	myIsTerminated

Detailed Description

template<typename TQuantity>
class DGtal::Statistic< TQuantity >

Aim: This class processes a set of sample values for one variable and can then compute different statistics, like sample mean, sample variance, sample unbiased variance, etc. It is minimalistic for space efficiency. For multiple variables, sample storage and others, see Statistics class.

Description of class 'Statistic'

Backported from ImaGene. [74]

See also

testStatistics.cpp

Template Parameters

TQuantity

any model of CCommutativeRing.

Definition at line 69 of file Statistic.h.

Member Typedef Documentation

ConstIterator

template<typename TQuantity >

typedef Container::const_iterator DGtal::Statistic< TQuantity >::ConstIterator

Definition at line 77 of file Statistic.h.

Container

template<typename TQuantity >

typedef std::vector< Quantity > DGtal::Statistic< TQuantity >::Container

Definition at line 76 of file Statistic.h.

Quantity

template<typename TQuantity >

typedef TQuantity DGtal::Statistic< TQuantity >::Quantity

Definition at line 74 of file Statistic.h.

Constructor & Destructor Documentation

~Statistic()

template<typename TQuantity >

DGtal::Statistic< TQuantity >::~Statistic

(

)

Destructor.

Statistic() [1/2]

template<typename TQuantity >

DGtal::Statistic< TQuantity >::Statistic

(

bool

storeSample = false

)

Constructor.

Statistic() [2/2]

template<typename TQuantity >

DGtal::Statistic< TQuantity >::Statistic

(

const Statistic< TQuantity > &

other

)

Copy constructor.

Parameters

other

the object to clone.

Member Function Documentation

addValue()

template<typename TQuantity >

void DGtal::Statistic< TQuantity >::addValue

(

Quantity

v

)

Adds a new sample value [v].

Parameters

v	the new sample value.

Referenced by checkGenericPlane(), checkPlane(), DGtal::CompareLocalEstimators< TFirstEsimator, TSecondEstimator >::compare(), DGtal::CompareLocalEstimators< TFirstEsimator, TSecondEstimator >::compareVectors(), testHistogramGaussian(), testHistogramGaussian2(), testHistogramUniform(), testStatistics(), and testStatisticsSaving().

addValues()

template<typename TQuantity >

template<class Iter >

void DGtal::Statistic< TQuantity >::addValues	(	Iter	b,
		Iter	e
	)

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

Exemple:

vector<Quantity> x;
Statistic stats;
stats.addValue( x + 4, x + 10 );

Parameters

b	an iterator on the starting point.
e	an iterator after the last point.

Referenced by DGtal::ShortcutsGeometry< TKSpace >::getStatistic().

begin()

template<typename TQuantity >

ConstIterator DGtal::Statistic< TQuantity >::begin

(

)

const

Returns

an iterator on the first stored value (if storeSample was set).

Referenced by testHistogramGaussian(), testHistogramGaussian2(), and testHistogramUniform().

BOOST_CONCEPT_ASSERT()

template<typename TQuantity >

DGtal::Statistic< TQuantity >::BOOST_CONCEPT_ASSERT

(

(concepts::CCommutativeRing< Quantity >)

)

clear()

template<typename TQuantity >

void DGtal::Statistic< TQuantity >::clear

(

)

Clears the object. As if it has just been created.

end()

template<typename TQuantity >

ConstIterator DGtal::Statistic< TQuantity >::end

(

)

const

Returns

an iterator after the last stored value (if storeSample was set).

Referenced by testHistogramGaussian(), testHistogramGaussian2(), and testHistogramUniform().

max()

template<typename TQuantity >

Quantity DGtal::Statistic< TQuantity >::max

(

)

const

Returns

the maximal value.

Referenced by testStatistics(), and testStatisticsSaving().

mean()

template<typename TQuantity >

double DGtal::Statistic< TQuantity >::mean

(

)

const

Returns

the sample mean (given as double).

Referenced by main(), testStatistics(), and testStatisticsSaving().

median()

template<typename TQuantity >

Quantity DGtal::Statistic< TQuantity >::median

(

)

Return the median value of the Statistic values. It can be given in two possible cases:

• if the the values are stored in the 'Statistic' objects (not always a good solution). (complexity: linear on average)
• if the values were first stored and computed by the function terminate().

  Returns

  the median value.

  See also

  terminate, Statistic

Referenced by testStatisticsSaving().

min()

template<typename TQuantity >

Quantity DGtal::Statistic< TQuantity >::min

(

)

const

Returns

the minimal value.

Referenced by testStatistics(), and testStatisticsSaving().

OK()

template<typename TQuantity >

bool DGtal::Statistic< TQuantity >::OK

(

)

const

Checks the validity/consistency of the object.

Returns

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

operator+()

template<typename TQuantity >

Statistic DGtal::Statistic< TQuantity >::operator+

(

const Statistic< TQuantity > &

other

)

const

Adds two set of statistics (should be of the same variable).

Parameters

other

the object to add.

Returns

a new object that is the union of these statistics.

operator+=()

template<typename TQuantity >

Statistic & DGtal::Statistic< TQuantity >::operator+=

(

const Statistic< TQuantity > &

other

)

Adds to self another set of statistics (should be of the same variable).

Parameters

other

the object to add.

Returns

a reference on 'this'.

operator=()

template<typename TQuantity >

Statistic & DGtal::Statistic< TQuantity >::operator=

(

const Statistic< TQuantity > &

other

)

Assignment.

Parameters

other

the object to copy.

Returns

a reference on 'this'.

operator[]()

template<typename TQuantity >

Quantity DGtal::Statistic< TQuantity >::operator[]

(

unsigned int

i

)

const

Parameters

[in]

i

a valid index

Returns

the corresponding value (if stored).

samples()

template<typename TQuantity >

unsigned int DGtal::Statistic< TQuantity >::samples

(

)

const

Returns

the number of samples.

Referenced by main().

selfDisplay()

template<typename TQuantity >

void DGtal::Statistic< TQuantity >::selfDisplay

(

std::ostream &

that_stream

)

const

Writes/Displays the object on an output stream.

Parameters

that_stream

the output stream where the object is written.

size()

template<typename TQuantity >

unsigned int DGtal::Statistic< TQuantity >::size

(

)

const

Returns

the number of samples.

terminate()

template<typename TQuantity >

void DGtal::Statistic< TQuantity >::terminate

(

)

Computes the median value of the statistics and switch to mode which does not save the statistics samples (myStoreSamples = false). Usefull only if the values are stored (specified in the the constructor) else it doest nothing.

See also

median, Statistic, myStoreSamples

Referenced by DGtal::CompareLocalEstimators< TFirstEsimator, TSecondEstimator >::compare(), DGtal::CompareLocalEstimators< TFirstEsimator, TSecondEstimator >::compareVectors(), DGtal::ShortcutsGeometry< TKSpace >::getStatistic(), main(), testHistogramGaussian(), testHistogramGaussian2(), testHistogramUniform(), testStatistics(), and testStatisticsSaving().

unbiasedVariance()

template<typename TQuantity >

double DGtal::Statistic< TQuantity >::unbiasedVariance

(

)

const

Returns

the unbiased sample variance (given as double).

variance()

template<typename TQuantity >

double DGtal::Statistic< TQuantity >::variance

(

)

const

Returns

the sample variance (given as double).

Referenced by main(), testStatistics(), and testStatisticsSaving().

Field Documentation

myExp

template<typename TQuantity >

Quantity DGtal::Statistic< TQuantity >::myExp

private

stores the sum of sample values for computing sample mean.

Definition at line 258 of file Statistic.h.

myExp2

template<typename TQuantity >

Quantity DGtal::Statistic< TQuantity >::myExp2

private

stores the sum of squared sample values for computing sample variance.

Definition at line 264 of file Statistic.h.

myIsTerminated

template<typename TQuantity >

bool DGtal::Statistic< TQuantity >::myIsTerminated

private

Tells if terminate was called. Usefull to return median value even if the m_values are no more stored (possible after serialisation which doest store the values.).

Definition at line 302 of file Statistic.h.

myMax

template<typename TQuantity >

Quantity DGtal::Statistic< TQuantity >::myMax

private

stores the maximal sample value.

Definition at line 269 of file Statistic.h.

myMedian

template<typename TQuantity >

Quantity DGtal::Statistic< TQuantity >::myMedian

private

stores the median sample value.

Definition at line 280 of file Statistic.h.

myMin

template<typename TQuantity >

Quantity DGtal::Statistic< TQuantity >::myMin

private

stores the minimal sample value.

Definition at line 274 of file Statistic.h.

mySamples

template<typename TQuantity >

unsigned int DGtal::Statistic< TQuantity >::mySamples

private

number of samples

Definition at line 253 of file Statistic.h.

myStoreSamples

template<typename TQuantity >

bool DGtal::Statistic< TQuantity >::myStoreSamples

private

Tells if values must be stored or not.

Definition at line 293 of file Statistic.h.

myValues

template<typename TQuantity >

Container DGtal::Statistic< TQuantity >::myValues

private

stores the sample to determine the median value

Definition at line 287 of file Statistic.h.

---

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

• Statistic.h