Description

Generic histogram class, capable of representing both unweighted and weighted distributions. Histogram data are stored as n+1 bin edges and n bin values, both being double-precision floating point values. Upper and lower outliers (as well as positive and negative infinities) are kept as counts (for unweighted statistics) or as sum of weights (for weighted statistics).

cHistogram is able to generate random numbers from the stored distribution, and also supports save/load of the histogram data in a file.

Bins can be set up directly using methods such as setBinEdges() or createUniformBins(), but it is often more practical to automate it by letting a histogram strategy do it. Histogram strategies are objects that encapsulate the job of setting up and managing histogram bins. For example, histogram strategies may employ a precollection phase to get an estimate of the distribution for laying out the bins. Strategies are also capable of extending the histogram range later by adding new bins as needed, or merging adjacent bins to reduce their count. Strategies that create non-uniform (e.g. equi-probable) bins are also possible to implement. Histogram strategies subclass from cIHistogramStrategy.

The default constructor of cHistogram installs a default histogram strategy which was designed to provide a good quality histogram for arbitrary distributions, without manual configuration. It employs precollection and also auto-extends the histogram at runtime, merging neighbouring groups of bins if there would be too many of them after extension.

Custom behavior can be achieved by setting up and installing an appropriate strategy class, such as cFixedRangeHistogramStrategy or cAutoRangeHistogramStrategy. There are also convenience methods such as setRange() and setNumBins() that internally use cAutoRangeHistogramStrategy.

Examples:

Automatic mode:

cHistogram histogram("histogram");

Setting up a 50-bin histogram on the range [0,100):

cAutoRangeHistogramStrategy *strategy = new cAutoRangeHistogramStrategy();
strategy->setRange(0, 100);
strategy->setNumBins(50);
strategy->setMode(cHistogram::MODE_INTEGERS);
cHistogram histogram("histogram", strategy);

The same effect using convenience methods:

cHistogram histogram("histogram");
histogram.setRange(0, 100);
histogram.setNumBins(50);
histogram.setMode(cHistogram::MODE_INTEGERS);

Inheritance diagram for cHistogram:

[legend]

Public Types
enum	Mode

Public Member Functions
Constructors, destructor, assignment.
	cHistogram (const char *name=nullptr, bool weighted=false)

	cHistogram (const char *name, int numBinsHint, bool weighted=false)

	cHistogram (const char name, cIHistogramStrategy strategy, bool weighted=false)

	cHistogram (const cHistogram &other)

cHistogram &	operator= (const cHistogram &other)

virtual	~cHistogram ()

Redefined cObject member functions.
virtual cHistogram *	dup () const override

virtual void	parsimPack (cCommBuffer *buffer) const override

virtual void	parsimUnpack (cCommBuffer *buffer) override

Redefined member functions from cStatistic and its subclasses.
virtual void	collect (double value) override

virtual void	collectWeighted (double value, double weight) override

virtual void	clear () override

virtual void	saveToFile (FILE *f) const override

virtual void	loadFromFile (FILE *f) override

virtual void	merge (const cStatistic *other) override

Configuring and querying the histogram.
void	setStrategy (cIHistogramStrategy *strategy)

cIHistogramStrategy *	getStrategy () const

virtual bool	binsAlreadySetUp () const override

virtual void	setUpBins () override

virtual void	setBinEdges (const std::vector< double > &edges)

virtual void	createUniformBins (double lo, double hi, double step)

virtual void	prependBins (const std::vector< double > &edges)

virtual void	appendBins (const std::vector< double > &edges)

virtual void	extendBinsTo (double value, double step, int maxNumBins=INT_MAX)

virtual void	mergeBins (int groupSize)

virtual std::vector< double >	getBinEdges () const override

virtual std::vector< double >	getBinValues () const override

virtual int	getNumBins () const override

virtual double	getBinEdge (int k) const override

virtual double	getBinValue (int k) const override

virtual double	getUnderflowSumWeights () const override

virtual double	getOverflowSumWeights () const override

virtual int64_t	getNumUnderflows () const override

virtual int64_t	getNumOverflows () const override

virtual int64_t	getNumNegInfs () const override

virtual int64_t	getNumPosInfs () const override

virtual double	getNegInfSumWeights () const override

virtual double	getPosInfSumWeights () const override

cAutoRangeHistogramStrategy-based convenience API.
virtual void	setMode (Mode mode)

virtual void	setRange (double lower, double upper)

virtual void	setNumPrecollectedValues (int numPrecollect)

virtual void	setRangeExtensionFactor (double rangeExtensionFactor)

virtual void	setAutoExtend (bool autoExtend)

virtual void	setNumBinsHint (int numCells)

virtual void	setBinSizeHint (double d)

Public Member Functions inherited from cAbstractHistogram
	cAbstractHistogram (const cAbstractHistogram &other)=default

	cAbstractHistogram (const char *name=nullptr, bool weighted=false)

virtual	~cAbstractHistogram ()

cAbstractHistogram &	operator= (const cAbstractHistogram &res)

virtual double	getBinPDF (int k) const

virtual Bin	getBinInfo (int k) const

virtual double	getPDF (double x) const

virtual double	getCDF (double x) const

virtual double	draw () const override

Public Member Functions inherited from cStdDev
	cStdDev (const cStdDev &r)

	cStdDev (const char *name=nullptr, bool weighted=false)

virtual	~cStdDev ()

cStdDev &	operator= (const cStdDev &res)

virtual std::string	str () const override

virtual bool	isWeighted () const override

virtual int64_t	getCount () const override

virtual double	getSum () const override

virtual double	getSqrSum () const override

virtual double	getMin () const override

virtual double	getMax () const override

virtual double	getMean () const override

virtual double	getStddev () const override

virtual double	getVariance () const override

virtual double	getSumWeights () const override

virtual double	getWeightedSum () const override

virtual double	getSqrSumWeights () const override

virtual double	getWeightedSqrSum () const override

virtual void	collect (double value)=0

virtual void	collect (SimTime value)

virtual void	collectWeighted (double value, double weight)

virtual void	collectWeighted (SimTime value, double weight)

virtual void	collectWeighted (double value, SimTime weight)

virtual void	collectWeighted (SimTime value, SimTime weight)

Public Member Functions inherited from cStatistic
	cStatistic (const cStatistic &r)

	cStatistic (const char *name=nullptr)

virtual	~cStatistic ()

cStatistic &	operator= (const cStatistic &res)

virtual void	collect (SimTime value)

virtual void	collectWeighted (SimTime value, double weight)

virtual void	collectWeighted (double value, SimTime weight)

virtual void	collectWeighted (SimTime value, SimTime weight)

virtual void	record ()

virtual void	recordWithUnit (const char *unit)

virtual void	recordAs (const char name, const char unit=nullptr)

Public Member Functions inherited from cRandom
	cRandom (cRNG *rng)

	cRandom (const char name=nullptr, cRNG rng=nullptr)

virtual	~cRandom ()

virtual void	setRNG (cRNG *rng)

cRNG *	getRNG () const

Public Member Functions inherited from cOwnedObject
	cOwnedObject ()

	cOwnedObject (const char *name, bool namepooling=true)

	cOwnedObject (const cOwnedObject &obj)

virtual	~cOwnedObject ()

cOwnedObject &	operator= (const cOwnedObject &o)

virtual cObject *	getOwner () const override

virtual bool	isOwnedObject () const override

Public Member Functions inherited from cNamedObject
	cNamedObject ()

	cNamedObject (const char *name, bool namepooling=true)

	cNamedObject (const cNamedObject &obj)

virtual	~cNamedObject ()

cNamedObject &	operator= (const cNamedObject &o)

virtual void	setName (const char *s)

virtual const char *	getName () const override

virtual void	setNamePooling (bool b)

virtual bool	getNamePooling ()

Public Member Functions inherited from cObject
	cObject ()

	cObject (const cObject &other)=default

virtual	~cObject ()

virtual const char *	getClassName () const

bool	isName (const char *s) const

virtual const char *	getFullName () const

virtual std::string	getFullPath () const

virtual std::string	getClassAndFullName () const

virtual std::string	getClassAndFullPath () const

const cObject *	getThisPtr () const

virtual std::ostream &	printOn (std::ostream &os) const

virtual bool	isSoftOwner () const

virtual void	forEachChild (cVisitor *v)

cObject *	findObject (const char *name, bool deep=true)

virtual cClassDescriptor *	getDescriptor () const

void	copyNotSupported () const

Additional Inherited Members
Static Public Member Functions inherited from cOwnedObject
static long	getTotalObjectCount ()

static long	getLiveObjectCount ()

static void	resetObjectCounters ()

static cSoftOwner *	getOwningContext ()

Protected Member Functions inherited from cObject
virtual void	take (cOwnedObject *obj)

virtual void	drop (cOwnedObject *obj)

void	dropAndDelete (cOwnedObject *obj)

Member Enumeration Documentation

◆ Mode

enum Mode

Histogram mode. In INTEGERS mode, bin edges are whole numbers; in REALS mode they can be real numbers.

Constructor & Destructor Documentation

◆ cHistogram() [1/4]

cHistogram	(	const char *	name = `nullptr`,
		bool	weighted = `false`
	)

explicit

This constructor installs a cDefaultHistogramStrategy on the histogram. To create a histogram without a strategy object, use the constructor that takes a 'strategy' parameter and pass nullptr for it.

◆ cHistogram() [2/4]

cHistogram	(	const char *	name,
		int	numBinsHint,
		bool	weighted = `false`
	)

explicit

This convenience constructor installs a cDefaultHistogramStrategy with the desired number of bins on the histogram.

◆ cHistogram() [3/4]

cHistogram	(	const char *	name,
		cIHistogramStrategy *	strategy,
		bool	weighted = `false`
	)

explicit

Constructor that allows one to install a histogram strategy on the histogram. It is also legal to pass nullptr as strategy.

◆ cHistogram() [4/4]

cHistogram ( const cHistogram & other )

inline

Copy constructor.

◆ ~cHistogram()

virtual ~cHistogram ( )

virtual

Destructor.

Member Function Documentation

◆ operator=()

cHistogram& operator= ( const cHistogram & other )

Assignment operator. The name member is not copied; see cNamedObject::operator=() for details.

◆ dup()

virtual cHistogram* dup ( ) const

inlineoverridevirtual

Creates and returns an exact copy of this object. See cObject for more details.

Reimplemented from cAbstractHistogram.

◆ parsimPack()

virtual void parsimPack ( cCommBuffer * buffer ) const

overridevirtual

Serializes the object into an MPI send buffer. Used by the simulation kernel for parallel execution. See cObject for more details.

Reimplemented from cStdDev.

◆ parsimUnpack()

virtual void parsimUnpack ( cCommBuffer * buffer )

overridevirtual

Deserializes the object from an MPI receive buffer Used by the simulation kernel for parallel execution. See cObject for more details.

Reimplemented from cStdDev.

◆ collect()

virtual void collect ( double value )

overridevirtual

Collects one observation. Delegates to the strategy object if there is one installed.

Reimplemented from cStdDev.

◆ collectWeighted()

virtual void collectWeighted	(	double	value,
		double	weight
	)

overridevirtual

Collects one observation with a given weight. The weight must not be negative. (Zero-weight observations are allowed, but will not affect mean and stddev, nor the bin values.) This methods delegates to the strategy object if there is one installed.

Reimplemented from cStdDev.

◆ clear()

virtual void clear ( )

overridevirtual

Clears the results collected so far.

Reimplemented from cStdDev.

◆ saveToFile()

virtual void saveToFile ( FILE * f ) const

overridevirtual

Writes the contents of the object into a text file.

Reimplemented from cStdDev.

◆ loadFromFile()

virtual void loadFromFile ( FILE * f )

overridevirtual

Reads the object data from a file, in the format written out by saveToFile().

Reimplemented from cStdDev.

◆ merge()

virtual void merge ( const cStatistic * other )

overridevirtual

Merge another statistics object into this one.

Reimplemented from cStdDev.

◆ setStrategy()

void setStrategy ( cIHistogramStrategy * strategy )

Installs a new histogram strategy, replacing the current one, taking ownership of 'setupStrategy'. Can only be called while the histogram is empty.

◆ getStrategy()

cIHistogramStrategy* getStrategy ( ) const

inline

Returns a pointer to the currently used histogram strategy.

◆ binsAlreadySetUp()

virtual bool binsAlreadySetUp ( ) const

overridevirtual

Returns true if histogram bins are already available. (Bins are not yet available in the precollection phase.) See setUpBins().

Implements cAbstractHistogram.

◆ setUpBins()

virtual void setUpBins ( )

overridevirtual

Sets up histogram bins using the installed strategy (see cIHistogramStrategy). The histogram strategy class may use precollection to gather information for laying out the bins.

Implements cAbstractHistogram.

◆ setBinEdges()

virtual void setBinEdges ( const std::vector< double > & edges )

virtual

Configures a histogram with bins defined by 'edges'. Can only be called once, and only when there are no bins defined. 'edges' must contain at least two values, and it must be strictly increasing.

◆ createUniformBins()

virtual void createUniformBins	(	double	lo,
		double	hi,
		double	step
	)

virtual

Sets the histogram up to have bins covering the range from 'lo' to 'hi', each bin being 'step' wide. Can only be called on a histogram without bins. 'lo' will always be added as an edge, all bins will be 'step' wide, and the last bin edge will be at or above 'hi'.

◆ prependBins()

virtual void prependBins ( const std::vector< double > & edges )

virtual

Extends the histogram to the left with some bins, as delimited by 'edges'. This can only be used if there is at least one bin already, and there are no underflows. 'edges' must not be empty, it must be strictly increasing, and its last value must be less than the first already existing bin edge.

◆ appendBins()

virtual void appendBins ( const std::vector< double > & edges )

virtual

Extends the histogram to the right with some bins, as delimited by 'edges'. This can only be used if there is at least one bin already, and there are no overflows. 'edges' must not be empty, it must be strictly increasing, and its first value must be greater than the last already existing bin edge.

◆ extendBinsTo()

virtual void extendBinsTo	(	double	value,
		double	step,
		int	maxNumBins = `INT_MAX`
	)

virtual

Makes sure that 'value' will fall in the range covered by the bins, by potentially extending the histogram with some bins of width 'step'. Creation of new bins stops when either the total number of bins reaches 'maxNumBins', or 'value' is covered by the histogram. If 'value' is already in the range of the existing bins, the function does nothing. This method may only be called when there are no over- or underflows. 'step' must be positive.

◆ mergeBins()

virtual void mergeBins ( int groupSize )

virtual

Reduces the number of bins by merging each 'groupSize' consecutive bins into one. The number of bins must be a multiple of 'groupSize'. If that is not the case, extendBinsTo() or similar methods may be used to create extra empty bins before calling this function.

◆ getBinEdges()

virtual std::vector<double> getBinEdges ( ) const

inlineoverridevirtual

Returns the bin edges of the histogram. There is always one more edge than bin, except when the histogram has not been set up yet, in which case both are zero.

Reimplemented from cAbstractHistogram.

◆ getBinValues()

virtual std::vector<double> getBinValues ( ) const

inlineoverridevirtual

Returns the bin values of the histogram. There is always one less bin than edge, except when the histogram has not been set up yet, in which case both are zero.

Reimplemented from cAbstractHistogram.

◆ getNumBins()

virtual int getNumBins ( ) const

inlineoverridevirtual

Returns the number of bins in the histogram.

Implements cAbstractHistogram.

◆ getBinEdge()

virtual double getBinEdge ( int k ) const

inlineoverridevirtual

Returns the k'th bin edge of the histogram. The k'th bin is delimited by the edge k and k+1.

Implements cAbstractHistogram.

◆ getBinValue()

virtual double getBinValue ( int k ) const

inlineoverridevirtual

Returns the total weight of the observations in the k'th bin of the histogram. (In the unweighted case, every observation is regarded as having the weight 1.0.)

Implements cAbstractHistogram.

◆ getUnderflowSumWeights()

virtual double getUnderflowSumWeights ( ) const

inlineoverridevirtual

Returns the total weight of the observations that were under the histogram range.

Implements cAbstractHistogram.

◆ getOverflowSumWeights()

virtual double getOverflowSumWeights ( ) const

inlineoverridevirtual

Returns the total weight of the observations that were above the histogram range.

Implements cAbstractHistogram.

◆ getNumUnderflows()

virtual int64_t getNumUnderflows ( ) const

overridevirtual

Returns the number of observations that were under the histogram range. This value is only collected for unweighted statistics, i.e. it is an error to call this method on a weighted histogram.

Implements cAbstractHistogram.

◆ getNumOverflows()

virtual int64_t getNumOverflows ( ) const

overridevirtual

Returns the number of observations that were under the histogram range. This value is only collected for unweighted statistics, i.e. it is an error to call this method on a weighted histogram.

Implements cAbstractHistogram.

◆ getNumNegInfs()

virtual int64_t getNumNegInfs ( ) const

overridevirtual

Returns number of observations that were negative infinity, independent of their weights. This value is only collected for unweighted statistics, i.e. it is an error to call this method on a weighted histogram.

Implements cAbstractHistogram.

◆ getNumPosInfs()

virtual int64_t getNumPosInfs ( ) const

overridevirtual

Returns number of observations that were positive infinity, independent of their weights. This value is only collected for unweighted statistics, i.e. it is an error to call this method on a weighted histogram.

Implements cAbstractHistogram.

◆ getNegInfSumWeights()

virtual double getNegInfSumWeights ( ) const

inlineoverridevirtual

Returns the total weight of the observations that were negative infinity.

Implements cAbstractHistogram.

◆ getPosInfSumWeights()

virtual double getPosInfSumWeights ( ) const

inlineoverridevirtual

Returns the total weight of the observations that were above the histogram range.

Implements cAbstractHistogram.

◆ setMode()

virtual void setMode ( Mode mode )

virtual

Sets the histogram mode: MODE_AUTO, MODE_INTEGERS or MODE_DOUBLES. Cannot be called when the bins have been set up already. This method internally installs (or uses an already installed) cAutoRangeHistogramStrategy on the histogram, and configures it accordingly.

◆ setRange()

virtual void setRange	(	double	lower,
		double	upper
	)

virtual

Sets the histogram range explicitly to [lower, upper). Use NAN to leave either or both values unspecified. This method internally installs (or uses an already installed) cAutoRangeHistogramStrategy on the histogram, and configures it accordingly.

◆ setNumPrecollectedValues()

virtual void setNumPrecollectedValues ( int numPrecollect )

virtual

Sets the number of observations to collect before setting up histogram bins. This method internally installs (or uses an already installed) cAutoRangeHistogramStrategy on the histogram, and configures it accordingly.

◆ setRangeExtensionFactor()

virtual void setRangeExtensionFactor ( double rangeExtensionFactor )

virtual

Sets the factor by which the range of the precollected observations is multiplied for determining the range of the histogram bins. This method internally installs (or uses an already installed) cAutoRangeHistogramStrategy on the histogram, and configures it accordingly.

◆ setAutoExtend()

virtual void setAutoExtend ( bool autoExtend )

virtual

When set to true, observations that fall outside of the histogram range will cause the histogram to be extended with new bins, instead of being collected as outliers. This method internally installs (or uses an already installed) cAutoRangeHistogramStrategy on the histogram, and configures it accordingly.

◆ setNumBinsHint()

virtual void setNumBinsHint ( int numCells )

virtual

Sets the preferred number of bins. Cannot be called when the bins have been set up already. This method internally installs (or uses an already installed) cAutoRangeHistogramStrategy on the histogram, and configures it accordingly.

◆ setBinSizeHint()

virtual void setBinSizeHint ( double d )

virtual

Sets the preferred bin size. Cannot be called when the bins have been set up already. This method internally installs (or uses an already installed) cAutoRangeHistogramStrategy on the histogram, and configures it accordingly.

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

chistogram.h

	OMNeT++ API 6.1 Discrete Event Simulation Library

Description

Public Types

Public Member Functions

Additional Inherited Members

Member Enumeration Documentation

◆ Mode

Constructor & Destructor Documentation

◆ cHistogram() [1/4]

◆ cHistogram() [2/4]

◆ cHistogram() [3/4]

◆ cHistogram() [4/4]

◆ ~cHistogram()

Member Function Documentation

◆ operator=()

◆ dup()

◆ parsimPack()

◆ parsimUnpack()

◆ collect()

◆ collectWeighted()

◆ clear()

◆ saveToFile()

◆ loadFromFile()

◆ merge()

◆ setStrategy()

◆ getStrategy()

◆ binsAlreadySetUp()

◆ setUpBins()

◆ setBinEdges()

◆ createUniformBins()

◆ prependBins()

◆ appendBins()

◆ extendBinsTo()

◆ mergeBins()

◆ getBinEdges()

◆ getBinValues()

◆ getNumBins()

◆ getBinEdge()

◆ getBinValue()

◆ getUnderflowSumWeights()

◆ getOverflowSumWeights()

◆ getNumUnderflows()

◆ getNumOverflows()

◆ getNumNegInfs()

◆ getNumPosInfs()

◆ getNegInfSumWeights()

◆ getPosInfSumWeights()

◆ setMode()

◆ setRange()

◆ setNumPrecollectedValues()

◆ setRangeExtensionFactor()

◆ setAutoExtend()

◆ setNumBinsHint()

◆ setBinSizeHint()