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

template<typename T, bool UserProvidedAddress>
class ROOT::Experimental::RNTupleView< T, UserProvidedAddress >

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

Template Parameters

T	The type of the object that will be read by the view
UserProvidedAddress	Whether the user provided an external memory location to read data into

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.

Fields of simple types with a Map() method will use that and thus expose zero-copy access.

Definition at line 144 of file RNTupleView.hxx.

Public Member Functions
	RNTupleView (const RNTupleView &other)=delete
	RNTupleView (RNTupleView &&other)=default
	~RNTupleView ()=default
void	Bind (std::shared_ptr< T > objPtr)
void	BindRawPtr (T *rawPtr)
void	EmplaceNew ()
const FieldT &	GetField () const
RNTupleGlobalRange	GetFieldRange () const
template<typename C = T, std::enable_if_t< Internal::isMappable< FieldT >, C * > = nullptr>
const C *	MapV (NTupleSize_t globalIndex, NTupleSize_t &nItems)
template<typename C = T, std::enable_if_t< Internal::isMappable< FieldT >, C * > = nullptr>
const C *	MapV (RClusterIndex clusterIndex, NTupleSize_t &nItems)
const T &	operator() (NTupleSize_t globalIndex)
const T &	operator() (RClusterIndex clusterIndex)
RNTupleView &	operator= (const RNTupleView &other)=delete
RNTupleView &	operator= (RNTupleView &&other)=default

Private Types
using	FieldT = RField< T >

Private Member Functions
	RNTupleView (DescriptorId_t fieldId, Internal::RPageSource *pageSource)
	RNTupleView (DescriptorId_t fieldId, Internal::RPageSource *pageSource, std::shared_ptr< T > objPtr)
	RNTupleView (DescriptorId_t fieldId, Internal::RPageSource *pageSource, T *rawPtr)
void	SetupField (DescriptorId_t fieldId, Internal::RPageSource *pageSource)

Private Attributes
FieldT	fField
	fFieldId has fParent always set to null; views access nested fields without looking at the parent
RFieldBase::RValue	fValue
	Used as a Read() destination for fields that are not mappable.

Friends
class	RNTupleCollectionView
class	RNTupleReader

#include <ROOT/RNTupleView.hxx>

Member Typedef Documentation

FieldT

template<typename T , bool UserProvidedAddress>

using ROOT::Experimental::RNTupleView< T, UserProvidedAddress >::FieldT = RField<T>

private

Definition at line 148 of file RNTupleView.hxx.

Constructor & Destructor Documentation

RNTupleView() [1/5]

template<typename T , bool UserProvidedAddress>

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

inlineprivate

Definition at line 166 of file RNTupleView.hxx.

RNTupleView() [2/5]

template<typename T , bool UserProvidedAddress>

ROOT::Experimental::RNTupleView< T, UserProvidedAddress >::RNTupleView ( DescriptorId_t  fieldId, Internal::RPageSource *  pageSource, std::shared_ptr< T >  objPtr  )

inlineprivate

Definition at line 173 of file RNTupleView.hxx.

RNTupleView() [3/5]

template<typename T , bool UserProvidedAddress>

ROOT::Experimental::RNTupleView< T, UserProvidedAddress >::RNTupleView ( DescriptorId_t  fieldId, Internal::RPageSource *  pageSource, T *  rawPtr  )

inlineprivate

Definition at line 180 of file RNTupleView.hxx.

RNTupleView() [4/5]

template<typename T , bool UserProvidedAddress>

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

delete

RNTupleView() [5/5]

template<typename T , bool UserProvidedAddress>

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

default

~RNTupleView()

template<typename T , bool UserProvidedAddress>

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

default

Member Function Documentation

Bind()

template<typename T , bool UserProvidedAddress>

void ROOT::Experimental::RNTupleView< T, UserProvidedAddress >::Bind ( std::shared_ptr< T >  objPtr )

inline

Definition at line 231 of file RNTupleView.hxx.

BindRawPtr()

template<typename T , bool UserProvidedAddress>

void ROOT::Experimental::RNTupleView< T, UserProvidedAddress >::BindRawPtr ( T *  rawPtr )

inline

Definition at line 240 of file RNTupleView.hxx.

EmplaceNew()

template<typename T , bool UserProvidedAddress>

void ROOT::Experimental::RNTupleView< T, UserProvidedAddress >::EmplaceNew ( )

inline

Definition at line 249 of file RNTupleView.hxx.

GetField()

template<typename T , bool UserProvidedAddress>

const FieldT & ROOT::Experimental::RNTupleView< T, UserProvidedAddress >::GetField ( ) const

inline

Definition at line 194 of file RNTupleView.hxx.

GetFieldRange()

template<typename T , bool UserProvidedAddress>

RNTupleGlobalRange ROOT::Experimental::RNTupleView< T, UserProvidedAddress >::GetFieldRange ( ) const

inline

Definition at line 195 of file RNTupleView.hxx.

MapV() [1/2]

template<typename T , bool UserProvidedAddress>

template<typename C = T, std::enable_if_t< Internal::isMappable< FieldT >, C * > = nullptr>

const C * ROOT::Experimental::RNTupleView< T, UserProvidedAddress >::MapV ( NTupleSize_t  globalIndex, NTupleSize_t &  nItems  )

inline

Definition at line 219 of file RNTupleView.hxx.

MapV() [2/2]

template<typename T , bool UserProvidedAddress>

template<typename C = T, std::enable_if_t< Internal::isMappable< FieldT >, C * > = nullptr>

const C * ROOT::Experimental::RNTupleView< T, UserProvidedAddress >::MapV ( RClusterIndex  clusterIndex, NTupleSize_t &  nItems  )

inline

Definition at line 226 of file RNTupleView.hxx.

operator()() [1/2]

template<typename T , bool UserProvidedAddress>

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

inline

Definition at line 197 of file RNTupleView.hxx.

operator()() [2/2]

template<typename T , bool UserProvidedAddress>

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

inline

Definition at line 207 of file RNTupleView.hxx.

operator=() [1/2]

template<typename T , bool UserProvidedAddress>

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

delete

operator=() [2/2]

template<typename T , bool UserProvidedAddress>

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

default

SetupField()

template<typename T , bool UserProvidedAddress>

void ROOT::Experimental::RNTupleView< T, UserProvidedAddress >::SetupField ( DescriptorId_t  fieldId, Internal::RPageSource *  pageSource  )

inlineprivate

Definition at line 156 of file RNTupleView.hxx.

Friends And Related Symbol Documentation

RNTupleCollectionView

template<typename T , bool UserProvidedAddress>

friend class RNTupleCollectionView

friend

Definition at line 146 of file RNTupleView.hxx.

RNTupleReader

template<typename T , bool UserProvidedAddress>

friend class RNTupleReader

friend

Definition at line 145 of file RNTupleView.hxx.

Member Data Documentation

fField

template<typename T , bool UserProvidedAddress>

FieldT ROOT::Experimental::RNTupleView< T, UserProvidedAddress >::fField

private

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

Definition at line 152 of file RNTupleView.hxx.

fValue

template<typename T , bool UserProvidedAddress>

RFieldBase::RValue ROOT::Experimental::RNTupleView< T, UserProvidedAddress >::fValue

private

Used as a Read() destination for fields that are not mappable.

Definition at line 154 of file RNTupleView.hxx.