OpenMS
BasicStatistics< RealT > Class Template Reference

Calculates some basic statistical parameters of a distribution: sum, mean, variance, and provides the normal approximation. More...

#include <OpenMS/MATH/STATISTICS/BasicStatistics.h>

Inheritance diagram for BasicStatistics< RealT >:
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Collaboration diagram for BasicStatistics< RealT >:
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Public Types

typedef RealT RealType
 The real type specified as template argument. More...
 
typedef std::vector< RealTypeprobability_container
 
typedef std::vector< RealTypecoordinate_container
 

Public Member Functions

 BasicStatistics ()
 Default constructor. More...
 
 BasicStatistics (BasicStatistics const &arg)
 Copy constructor. More...
 
BasicStatisticsoperator= (BasicStatistics const &arg)
 Assignment. More...
 
void clear ()
 Set sum, mean, and variance to zero. More...
 
template<typename ProbabilityIterator >
void update (ProbabilityIterator probability_begin, ProbabilityIterator const probability_end)
 This does the actual calculation. More...
 
template<typename ProbabilityIterator , typename CoordinateIterator >
void update (ProbabilityIterator const probability_begin, ProbabilityIterator const probability_end, CoordinateIterator const coordinate_begin)
 This does the actual calculation. More...
 
RealType mean () const
 Returns the mean. More...
 
void setMean (RealType const &mean)
 
RealType variance () const
 Returns the variance. More...
 
void setVariance (RealType const &variance)
 
RealType sum () const
 Returns the sum. More...
 
void setSum (RealType const &sum)
 
RealType normalDensity_sqrt2pi (RealType coordinate) const
 Returns the density of the normal approximation at point, multiplied by sqrt( 2 * pi ). This saves a division operation compared to normalDensity() More...
 
RealType normalDensity (RealType const coordinate) const
 See normalDensity_sqrt2pi(). Returns the density of the normal distribution at point. More...
 
void normalApproximation (probability_container &probability)
 The argument probability is filled with values according to the normal approximation. Its size() is not changed. The approximation takes place at coordinate positions 0, 1, ..., size()-1. More...
 
void normalApproximation (probability_container &probability, typename probability_container::size_type const size)
 
void normalApproximation (probability_container &probability, coordinate_container const &coordinate)
 The argument probability is filled with values according to the normal approximation. The second argument coordinate contains the positions where the approximation takes place. probability.size() is set to coordinate.size(). More...
 

Static Public Member Functions

static RealType sqrt2pi ()
 Returns sqrt( 2 * pi ), which is useful to normalize the result of normalDensity_sqrt2pi(). More...
 

Protected Attributes

Protected Members
RealType mean_
 
RealType variance_
 
RealType sum_
 

Private Member Functions

Private Methods
void normalApproximationHelper_ (probability_container &probability, typename probability_container::size_type const size)
 
void normalApproximationHelper_ (probability_container &probability, coordinate_container const &coordinate)
 

Related Functions

(Note that these are not member functions.)

std::ostream & operator<< (std::ostream &os, BasicStatistics &arg)
 A convenient overload for debugging purposes. More...
 

Detailed Description

template<typename RealT = double>
class OpenMS::Math::BasicStatistics< RealT >

Calculates some basic statistical parameters of a distribution: sum, mean, variance, and provides the normal approximation.

The intended usage is as follows:

  • create an instance
  • set the basic statistical parameters by either
    • calling one of the update() member functions, or
    • using the set... methods
  • do something with the basic statistical parameters, e.g.
    • using the get... methods, or
    • obtain samples from a normal approximation with these parameters
    • whatever member function you might want to add to this class ;-)

Member Typedef Documentation

◆ coordinate_container

typedef std::vector<RealType> coordinate_container

◆ probability_container

typedef std::vector<RealType> probability_container

◆ RealType

typedef RealT RealType

The real type specified as template argument.

Constructor & Destructor Documentation

◆ BasicStatistics() [1/2]

BasicStatistics ( )
inline

Default constructor.

◆ BasicStatistics() [2/2]

BasicStatistics ( BasicStatistics< RealT > const &  arg)
inline

Copy constructor.

Member Function Documentation

◆ clear()

void clear ( )
inline

Set sum, mean, and variance to zero.

◆ mean()

RealType mean ( ) const
inline

Returns the mean.

◆ normalApproximation() [1/3]

void normalApproximation ( probability_container probability)
inline

The argument probability is filled with values according to the normal approximation. Its size() is not changed. The approximation takes place at coordinate positions 0, 1, ..., size()-1.

◆ normalApproximation() [2/3]

void normalApproximation ( probability_container probability,
coordinate_container const &  coordinate 
)
inline

The argument probability is filled with values according to the normal approximation. The second argument coordinate contains the positions where the approximation takes place. probability.size() is set to coordinate.size().

◆ normalApproximation() [3/3]

void normalApproximation ( probability_container probability,
typename probability_container::size_type const  size 
)
inline

The argument probability is filled with values according to the normal approximation. Its size() is set to size. The approximation takes place at coordinate positions 0, 1, ..., size-1.

◆ normalApproximationHelper_() [1/2]

void normalApproximationHelper_ ( probability_container probability,
coordinate_container const &  coordinate 
)
inlineprivate

References OpenMS::Math::sum().

◆ normalApproximationHelper_() [2/2]

void normalApproximationHelper_ ( probability_container probability,
typename probability_container::size_type const  size 
)
inlineprivate

References OpenMS::Math::sum().

◆ normalDensity()

RealType normalDensity ( RealType const  coordinate) const
inline

See normalDensity_sqrt2pi(). Returns the density of the normal distribution at point.

◆ normalDensity_sqrt2pi()

RealType normalDensity_sqrt2pi ( RealType  coordinate) const
inline

Returns the density of the normal approximation at point, multiplied by sqrt( 2 * pi ). This saves a division operation compared to normalDensity()

References OpenMS::Math::mean(), and OpenMS::Math::variance().

◆ operator=()

◆ setMean()

void setMean ( RealType const &  mean)
inline

References OpenMS::Math::mean().

◆ setSum()

void setSum ( RealType const &  sum)
inline

References OpenMS::Math::sum().

◆ setVariance()

void setVariance ( RealType const &  variance)
inline

◆ sqrt2pi()

static RealType sqrt2pi ( )
inlinestatic

Returns sqrt( 2 * pi ), which is useful to normalize the result of normalDensity_sqrt2pi().

◆ sum()

RealType sum ( ) const
inline

Returns the sum.

◆ update() [1/2]

void update ( ProbabilityIterator const  probability_begin,
ProbabilityIterator const  probability_end,
CoordinateIterator const  coordinate_begin 
)
inline

This does the actual calculation.

You can call this as often as you like, using different input vectors.

◆ update() [2/2]

void update ( ProbabilityIterator  probability_begin,
ProbabilityIterator const  probability_end 
)
inline

This does the actual calculation.

You can call this as often as you like, using different input vectors.

◆ variance()

RealType variance ( ) const
inline

Returns the variance.

Friends And Related Function Documentation

◆ operator<<

std::ostream& operator<< ( std::ostream &  os,
BasicStatistics< RealT > &  arg 
)
friend

A convenient overload for debugging purposes.

Member Data Documentation

◆ mean_

RealType mean_
protected

◆ sum_

RealType sum_
protected

◆ variance_

RealType variance_
protected