WelfordRunner Class Reference

Implements the Welford Online one-pass algorithm. More...

#include <subtotal.hxx>

Public Member Functions
	WelfordRunner ()
void	update (double fVal)
sal_uInt64	getCount () const
double	getVarianceSample () const
double	getVariancePopulation () const

Private Attributes
double	mfMean
double	mfM2
sal_uInt64	mnCount

Friends
class	ScFunctionData

Detailed Description

Implements the Welford Online one-pass algorithm.

See https://en.wikipedia.org/wiki/Algorithms_for_calculating_variance#Welford's_Online_algorithm and Donald E. Knuth, TAoCP vol.2, 3rd edn., p. 232

Definition at line 38 of file subtotal.hxx.

Constructor & Destructor Documentation

WelfordRunner()

WelfordRunner::WelfordRunner ( )

inline

Definition at line 41 of file subtotal.hxx.

Member Function Documentation

getCount()

sal_uInt64 WelfordRunner::getCount ( ) const

inline

Definition at line 43 of file subtotal.hxx.

References mnCount.

Referenced by ScDPAggData::Calculate(), and ScFunctionData::getResult().

getVariancePopulation()

double WelfordRunner::getVariancePopulation ( ) const

inline

Definition at line 45 of file subtotal.hxx.

References mfM2, and mnCount.

Referenced by ScDPAggData::Calculate(), and ScFunctionData::getResult().

getVarianceSample()

double WelfordRunner::getVarianceSample ( ) const

inline

Definition at line 44 of file subtotal.hxx.

References mfM2, and mnCount.

Referenced by ScDPAggData::Calculate(), and ScFunctionData::getResult().

update()

void WelfordRunner::update

(

double

fVal

)

Definition at line 196 of file subtotal.cxx.

References mfM2, mfMean, and mnCount.

Referenced by ScDPAggData::Update(), and ScFunctionData::update().

Friends And Related Function Documentation

ScFunctionData

friend class ScFunctionData

friend

Definition at line 52 of file subtotal.hxx.

Member Data Documentation

mfM2

double WelfordRunner::mfM2

private

Definition at line 55 of file subtotal.hxx.

Referenced by getVariancePopulation(), getVarianceSample(), and update().

mfMean

double WelfordRunner::mfMean

private

Definition at line 54 of file subtotal.hxx.

Referenced by ScFunctionData::getValueRef(), and update().

mnCount

sal_uInt64 WelfordRunner::mnCount

private

Definition at line 56 of file subtotal.hxx.

Referenced by getCount(), ScFunctionData::getCountRef(), getVariancePopulation(), getVarianceSample(), and update().

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

• subtotal.hxx
• subtotal.cxx