ROOT::Experimental::RNTupleView< T > Class Template Reference

template<typename T>
class ROOT::Experimental::RNTupleView< T >

An RNTupleView provides read-only access to a single field of the ntuple.

(NB(jblomer): The ntuple view is very close to TTreeReader. Do we simply want to teach TTreeReader to deal with RNTuple?)

The view owns a field and its underlying columns in order to fill an ntuple value object with data. Data can be accessed by index. For top level fields, the index refers to the entry number. Fields that are part of nested collections have global index numbers that are derived from their parent indexes.

The RNTupleView object is an iterable. That means, all field values in the tree can be sequentially read from begin() to end().

For simple types, template specializations let the reading become a pure mapping into a page buffer.

Definition at line 124 of file RNTupleView.hxx.

Public Member Functions
	RNTupleView (const RNTupleView &other)=delete
	RNTupleView (RNTupleView &&other)=default
	~RNTupleView ()
const T &	operator() (const RClusterIndex &clusterIndex)
const T &	operator() (NTupleSize_t globalIndex)
RNTupleView &	operator= (const RNTupleView &other)=delete
RNTupleView &	operator= (RNTupleView &&other)=default

Protected Member Functions
	RNTupleView (DescriptorId_t fieldId, Detail::RPageSource *pageSource)

Protected Attributes
RField< T >	fField
	fFieldId has fParent always set to null; views access nested fields without looking at the parent More...
Detail::RFieldValue	fValue

Friends
class	RNTupleReader
class	RNTupleViewCollection

#include <ROOT/RNTupleView.hxx>

Constructor & Destructor Documentation

RNTupleView() [1/3]

template<typename T >

ROOT::Experimental::RNTupleView< T >::RNTupleView ( DescriptorId_t  fieldId, Detail::RPageSource *  pageSource  )

inlineprotected

Definition at line 135 of file RNTupleView.hxx.

RNTupleView() [2/3]

template<typename T >

ROOT::Experimental::RNTupleView< T >::RNTupleView ( const RNTupleView< T > &  other )

delete

RNTupleView() [3/3]

template<typename T >

ROOT::Experimental::RNTupleView< T >::RNTupleView ( RNTupleView< T > &&  other )

default

~RNTupleView()

template<typename T >

ROOT::Experimental::RNTupleView< T >::~RNTupleView ( )

inline

Definition at line 153 of file RNTupleView.hxx.

Member Function Documentation

operator()() [1/2]

template<typename T >

const T & ROOT::Experimental::RNTupleView< T >::operator() ( const RClusterIndex &  clusterIndex )

inline

Definition at line 160 of file RNTupleView.hxx.

operator()() [2/2]

template<typename T >

const T & ROOT::Experimental::RNTupleView< T >::operator() ( NTupleSize_t  globalIndex )

inline

Definition at line 155 of file RNTupleView.hxx.

operator=() [1/2]

template<typename T >

RNTupleView & ROOT::Experimental::RNTupleView< T >::operator= ( const RNTupleView< T > &  other )

delete

operator=() [2/2]

template<typename T >

RNTupleView & ROOT::Experimental::RNTupleView< T >::operator= ( RNTupleView< T > &&  other )

default

Friends And Related Function Documentation

RNTupleReader

template<typename T >

friend class RNTupleReader

friend

Definition at line 125 of file RNTupleView.hxx.

RNTupleViewCollection

template<typename T >

friend class RNTupleViewCollection

friend

Definition at line 126 of file RNTupleView.hxx.

Member Data Documentation

fField

template<typename T >

RField<T> ROOT::Experimental::RNTupleView< T >::fField

protected

fFieldId has fParent always set to null; views access nested fields without looking at the parent

Definition at line 132 of file RNTupleView.hxx.

fValue

template<typename T >

Detail::RFieldValue ROOT::Experimental::RNTupleView< T >::fValue

protected

Definition at line 133 of file RNTupleView.hxx.

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

• tree/ntuple/v7/inc/ROOT/RNTupleView.hxx