#include <Stats_T.h>

Inheritance diagram for OpenDDS::DCPS::Stats< DataType >:

Collaboration diagram for OpenDDS::DCPS::Stats< DataType >:

Public Member Functions
	Stats (unsigned int amount=0, typename DataCollector< DataType >::OnFull type=DataCollector< DataType >::KeepOldest)
	Default constructor. More...

	Stats (const Stats &)

Stats &	operator= (const Stats &rhs)
	Default bitwise copy is sufficient. More...

void	reset ()
	Reset statistics to nil. More...

void	add (DataType value)

long double	mean () const
	Calculate the average value. More...

long double	var () const
	Calculate the variance value. More...

DataType	minimum () const
	Access the minimum value. More...

DataType	maximum () const
	Access the maximum value. More...

unsigned long	n () const
	Access the number of values accumulated. More...

Public Member Functions inherited from OpenDDS::DCPS::DataCollector< DataType >
	DataCollector (unsigned int bound=0, OnFull onFull=KeepOldest)

virtual	~DataCollector ()
	Allow the class to be extended. More...

void	collect (const DataType &datum)
	Implement data collection. More...

unsigned int	size () const
	Amount of data actually stored. More...

DataCollector< DataType > &	operator<< (DataType datum)

std::ostream &	insert (std::ostream &str) const
	Implement insertion of collected data onto an ostream. More...

Private Attributes
unsigned long	n_

DataType	minimum_

DataType	maximum_

long double	an_

long double	bn_

long double	cn_

long double	variance_

Additional Inherited Members
Public Types inherited from OpenDDS::DCPS::DataCollector< DataType >
enum	OnFull
	Selectors for behavior when buffer fills. More...

Detailed Description

template<typename DataType>
class OpenDDS::DCPS::Stats< DataType >

Definition at line 28 of file Stats_T.h.

Constructor & Destructor Documentation

◆ Stats() [1/2]

template<typename DataType>

OpenDDS::DCPS::Stats< DataType >::Stats	(	unsigned int	amount = `0`,
		typename DataCollector< DataType >::OnFull	type = `DataCollector<DataType>::KeepOldest`
	)

inline

Default constructor.

Definition at line 81 of file Stats_T.h.

                                                : DataCollector<DataType>(amount, type)
 {
   this->reset();
 }

◆ Stats() [2/2]

template<typename DataType>

OpenDDS::DCPS::Stats< DataType >::Stats ( const Stats< DataType > & )

Member Function Documentation

◆ add()

template<typename DataType>

void OpenDDS::DCPS::Stats< DataType >::add ( DataType value )

inline

Accumulate a new value.

Parameters

value the new value to be accumulated.

Definition at line 133 of file Stats_T.h.

Referenced by OpenDDS::DCPS::WriterStats::add_stat().

 {
   // Save the raw value if configured to.
   this->collect(value);
 
   // Slide rule style calculations.
   long double term;
 
   //
   // V(N+1) = V(N) * N^2 / (N+1)^2
   //        + A(N)
   //        - B(N) * X(N+1)
   //        + C(N) * X(N+1)^2
   //
   this->variance_ /= (this->n_ + 1);
   this->variance_ *=  this->n_;
   this->variance_ /= (this->n_ + 1);
   this->variance_ *=  this->n_;
 
   term = static_cast<long double>(value);
   this->variance_ +=  this->an_;
   this->variance_ -=  this->bn_ * term;
   this->variance_ +=  this->cn_ * term * term;
 
   // The internal variable updates _must_ follow the variance update.
 
   //
   // A(N+1) = (A(N) * (N+1)^2 / (N+2)^2) + (X(N+1) / (N+2)^2)
   //
   this->an_ /= (this->n_ + 2);
   this->an_ *= (this->n_ + 1);
   this->an_ /= (this->n_ + 2);
   this->an_ *= (this->n_ + 1);
 
   // term = static_cast<long double>( value);
   term *= term;
   term /= (this->n_ + 2);
   term /= (this->n_ + 2);
   this->an_ += term;
 
   //
   // B(N+1) = (B(N) * (N+1)^2 / (N+2)^2) + (2 * X(N+1) / (N+2)^2)
   //
   this->bn_ /= (this->n_ + 2);
   this->bn_ *= (this->n_ + 1);
   this->bn_ /= (this->n_ + 2);
   this->bn_ *= (this->n_ + 1);
 
   term = static_cast<long double>(value * 2);
   term /= (this->n_ + 2);
   term /= (this->n_ + 2);
   this->bn_ += term;
 
   //
   // C(N+1) = (N+1) / (N+2)^2
   //
   this->cn_  =  this->n_ + 1;
   this->cn_ /= (this->n_ + 2);
   this->cn_ /= (this->n_ + 2);
 
   if ((this->n_ == 0) || (value < this->minimum_)) {
     this->minimum_ = value;
   }
 
   if ((this->n_ == 0) || (value > this->maximum_)) {
     this->maximum_ = value;
   }
 
   this->n_ += 1; // Must follow internal variable updates.
 }

◆ maximum()

template<typename DataType >

DataType OpenDDS::DCPS::Stats< DataType >::maximum ( ) const

inline

Access the maximum value.

: return qNaN with no data.

Definition at line 248 of file Stats_T.h.

Referenced by OpenDDS::DCPS::WriterStats::get_stats().

 {
   /// @TODO: return qNaN with no data.
   return (this->n_ == 0)? 0: this->maximum_;
 }

◆ mean()

template<typename DataType >

long double OpenDDS::DCPS::Stats< DataType >::mean ( ) const

inline

Calculate the average value.

: return qNaN with no data.

Definition at line 207 of file Stats_T.h.

Referenced by OpenDDS::DCPS::WriterStats::get_stats().

 {
   if (this->n_ == 0) {
     /// @TODO: return qNaN with no data.
     return 0.0;
   }
 
   // Slide rule style calculations.
 
   //
   // MEAN = B(N) * (N+1)^2 / (2 * N)
   //
   long double average = this->bn_ / 2.0 ;
 
   average *= (this->n_ + 1) ;
   average /=  this->n_ ;
   average *= (this->n_ + 1) ;
 
   return average ;
 }

◆ minimum()

template<typename DataType >

DataType OpenDDS::DCPS::Stats< DataType >::minimum ( ) const

inline

Access the minimum value.

: return qNaN with no data.

Definition at line 239 of file Stats_T.h.

Referenced by OpenDDS::DCPS::WriterStats::get_stats().

 {
   /// @TODO: return qNaN with no data.
   return (this->n_ == 0)? 0: this->minimum_;
 }

◆ n()

template<typename DataType >

unsigned long OpenDDS::DCPS::Stats< DataType >::n ( ) const

inline

Access the number of values accumulated.

Definition at line 257 of file Stats_T.h.

Referenced by OpenDDS::DCPS::WriterStats::get_stats(), and OpenDDS::DCPS::WriterStats::raw_data().

 {
   return this->n_;
 }

◆ operator=()

template<typename DataType >

Stats< DataType > & OpenDDS::DCPS::Stats< DataType >::operator= ( const Stats< DataType > & rhs )

inline

Default bitwise copy is sufficient.

Assignment operator

Definition at line 104 of file Stats_T.h.

 {
   this->n_        = rhs.n_;
   this->minimum_  = rhs.minimum_;
   this->maximum_  = rhs.maximum_;
   this->an_       = rhs.an_ ;
   this->bn_       = rhs.bn_ ;
   this->cn_       = rhs.cn_ ;
   this->variance_ = rhs.variance_ ;
   return *this;
 }

◆ reset()

template<typename DataType >

void OpenDDS::DCPS::Stats< DataType >::reset ( void )

inline

Reset statistics to nil.

Definition at line 119 of file Stats_T.h.

Referenced by OpenDDS::DCPS::WriterStats::reset_stats().

 {
   this->n_        = 0;
   this->minimum_  = static_cast<DataType>(0);
   this->maximum_  = static_cast<DataType>(0);
   this->an_       = 0.0;
   this->bn_       = 0.0;
   this->cn_       = 0.0;
   this->variance_ = 0.0;
 }

◆ var()

template<typename DataType >

long double OpenDDS::DCPS::Stats< DataType >::var ( ) const

inline

Calculate the variance value.

Definition at line 231 of file Stats_T.h.

Referenced by OpenDDS::DCPS::WriterStats::get_stats().

 {
   return this->variance_ ;
 }

Referenced by OpenDDS::DCPS::Stats< double >::operator=().

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

Stats_T.h

Public Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

template<typename DataType> class OpenDDS::DCPS::Stats< DataType >

Constructor & Destructor Documentation

◆ Stats() [1/2]

◆ Stats() [2/2]

Member Function Documentation

◆ add()

◆ maximum()

◆ mean()

◆ minimum()

◆ n()

◆ operator=()

◆ reset()

◆ var()

Member Data Documentation

◆ an_

◆ bn_

◆ cn_

◆ maximum_

◆ minimum_

◆ n_

◆ variance_

template<typename DataType>
class OpenDDS::DCPS::Stats< DataType >