Specialization of RMergeableValue for the StdDev action.

This class also stores information about the number of entries and the average used to compute the standard deviation.

Definition at line 426 of file RMergeableValue.hxx.

Public Member Functions
	RMergeableStdDev ()=default
	Default constructor.

	RMergeableStdDev (const RMergeableStdDev &)=delete

	RMergeableStdDev (Double_t value, ULong64_t counts, Double_t mean)
	Constructor that initializes data members.

	RMergeableStdDev (RMergeableStdDev &&)=default

Public Member Functions inherited from ROOT::Detail::RDF::RMergeableValue< Double_t >
	RMergeableValue ()=default
	Default constructor.

	RMergeableValue (const Double_t &value)
	Constructor taking the action result by const reference.

const Double_t &	GetValue () const
	Retrieve the result wrapped by this mergeable.

Public Member Functions inherited from ROOT::Detail::RDF::RMergeableValueBase
	RMergeableValueBase ()=default
	Default constructor.

virtual	~RMergeableValueBase ()=default

Private Member Functions
void	Merge (const RMergeableValue< Double_t > &other) final
	Aggregate the information contained in another RMergeableValue into this.

Private Attributes
ULong64_t	fCounts
	Number of entries of the set.

Double_t	fMean
	Average of the set.

Additional Inherited Members
Protected Attributes inherited from ROOT::Detail::RDF::RMergeableValue< Double_t >
Double_t	fValue

#include <ROOT/RDF/RMergeableValue.hxx>

Inheritance diagram for ROOT::Detail::RDF::RMergeableStdDev:

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Constructor & Destructor Documentation

◆ RMergeableStdDev() [1/4]

ROOT::Detail::RDF::RMergeableStdDev::RMergeableStdDev	(	Double_t	value,
		ULong64_t	counts,
		Double_t	mean
	)

inline

Constructor that initializes data members.

Parameters

[in]	value	The action result.
[in]	counts	The number of entries of the set.
[in]	mean	The average of the set.

Definition at line 485 of file RMergeableValue.hxx.

◆ RMergeableStdDev() [2/4]

ROOT::Detail::RDF::RMergeableStdDev::RMergeableStdDev ( )

default

Default constructor.

Needed to allow serialization of ROOT objects. See [TBufferFile::WriteObjectClass] (classTBufferFile.html::a209078a4cb58373b627390790bf0c9c1)

◆ RMergeableStdDev() [3/4]

ROOT::Detail::RDF::RMergeableStdDev::RMergeableStdDev ( RMergeableStdDev && )

default

◆ RMergeableStdDev() [4/4]

ROOT::Detail::RDF::RMergeableStdDev::RMergeableStdDev ( const RMergeableStdDev & )

delete

Member Function Documentation

◆ Merge()

void ROOT::Detail::RDF::RMergeableStdDev::Merge ( const RMergeableValue< Double_t > & other )

inlinefinalprivatevirtual

Aggregate the information contained in another RMergeableValue into this.

Parameters

[in] other Another RMergeableValue object.

Exceptions

std::invalid_argument If the cast of the other object to the same type as this one fails.

The other RMergeableValue object is cast to the same type as this object. This is needed to make sure that only results of the same type of action are merged together. The function then computes the aggregated standard deviation of the two samples using an algorithm by [Chan et al. (1979)] (http://i.stanford.edu/pub/cstr/reports/cs/tr/79/773/CS-TR-79-773.pdf)

Note: All the Merge methods in the RMergeableValue family are private. To merge multiple RMergeableValue objects please use [MergeValues] (namespaceROOT_1_1Detail_1_1RDF.html::af16fefbe2d120983123ddf8a1e137277).

Implements ROOT::Detail::RDF::RMergeableValue< Double_t >.

Definition at line 447 of file RMergeableValue.hxx.

Member Data Documentation

◆ fCounts

ULong64_t ROOT::Detail::RDF::RMergeableStdDev::fCounts

private

Number of entries of the set.

Definition at line 427 of file RMergeableValue.hxx.

◆ fMean

Double_t ROOT::Detail::RDF::RMergeableStdDev::fMean

private

Average of the set.

Definition at line 428 of file RMergeableValue.hxx.

Libraries for ROOT::Detail::RDF::RMergeableStdDev:

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

tree/dataframe/inc/ROOT/RDF/RMergeableValue.hxx

Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members