ROOT::Internal::TDF::TColumnValue< T > Class Template Reference

template<typename T>
class ROOT::Internal::TDF::TColumnValue< T >

Helper class that updates and returns TTree branches as well as TDataFrame temporary columns.

Template Parameters

T	The type of the column

TDataFrame nodes must access two different types of values during the event loop: values of real branches, for which TTreeReader{Values,Arrays} act as proxies, or temporary columns whose values are generated on the fly. While the type of the value is known at compile time (or just-in-time), it is only at runtime that nodes can check whether a certain value is generated on the fly or not.

TColumnValuePtr abstracts this difference by providing the same interface for both cases and handling the reading or generation of new values transparently. Only one of the two data members fReaderProxy or fValuePtr will be non-null for a given TColumnValue, depending on whether the value comes from a real TTree branch or from a temporary column respectively.

TDataFrame nodes can store tuples of TColumnValues and retrieve an updated value for the column via the Get method.

Definition at line 129 of file TDFNodes.hxx.

Public Member Functions
	TColumnValue ()=default
template<typename U = T, typename std::enable_if< std::is_same< typename TColumnValue< U >::ProxyParam_t, U >::value, int >::type = 0>
T &	Get (Long64_t entry)
template<typename U = T, typename std::enable_if<!std::is_same< ProxyParam_t, U >::value, int >::type = 0>
std::array_view< ProxyParam_t >	Get (Long64_t)
void	MakeProxy (TTreeReader *r, const std::string &bn)
void	Reset ()
void	SetTmpColumn (unsigned int slot, TCustomColumnBase *tmpColumn)

Private Types
using	ProxyParam_t = typename std::conditional< std::is_same< ReaderValueOrArray_t< T >, TTreeReaderValue< T >>::value, T, ExtractType_t< T >>::type

Private Attributes
std::unique_ptr < TTreeReaderArray < ProxyParam_t > >	fReaderArray {nullptr}
	non-temporary columns and T != std::array_view<U> More...
std::unique_ptr < TTreeReaderValue< T > >	fReaderValue {nullptr}
unsigned int	fSlot {0}
TCustomColumnBase *	fTmpColumn {nullptr}
T *	fValuePtr {nullptr}
	non-temporary columsn and T == std::array_view<U>. More...

#include <ROOT/TDFNodes.hxx>

Member Typedef Documentation

template<typename T >

using ROOT::Internal::TDF::TColumnValue< T >::ProxyParam_t = typename std::conditional<std::is_same<ReaderValueOrArray_t<T>, TTreeReaderValue<T>>::value, T, ExtractType_t<T>>::type

private

Definition at line 133 of file TDFNodes.hxx.

Constructor & Destructor Documentation

template<typename T >

ROOT::Internal::TDF::TColumnValue< T >::TColumnValue ( )

default

Member Function Documentation

template<typename T >

template<typename U , typename std::enable_if< std::is_same< typename ROOT::Internal::TDF::TColumnValue< U >::ProxyParam_t, U >::value, int >::type >

T & ROOT::Internal::TDF::TColumnValue< T >::Get

(

Long64_t

entry

)

Definition at line 570 of file TDFNodes.hxx.

template<typename T >

template<typename U = T, typename std::enable_if<!std::is_same< ProxyParam_t, U >::value, int >::type = 0>

std::array_view<ProxyParam_t> ROOT::Internal::TDF::TColumnValue< T >::Get ( Long64_t  )

inline

Definition at line 163 of file TDFNodes.hxx.

template<typename T >

void ROOT::Internal::TDF::TColumnValue< T >::MakeProxy ( TTreeReader *  r, const std::string &  bn  )

inline

Definition at line 148 of file TDFNodes.hxx.

template<typename T >

void ROOT::Internal::TDF::TColumnValue< T >::Reset ( void  )

inline

Definition at line 177 of file TDFNodes.hxx.

template<typename T >

void ROOT::Internal::TDF::TColumnValue< T >::SetTmpColumn	(	unsigned int	slot,
		TCustomColumnBase *	tmpColumn
	)

Definition at line 550 of file TDFNodes.hxx.

Member Data Documentation

template<typename T >

std::unique_ptr<TTreeReaderArray<ProxyParam_t> > ROOT::Internal::TDF::TColumnValue< T >::fReaderArray {nullptr}

private

non-temporary columns and T != std::array_view<U>

Definition at line 136 of file TDFNodes.hxx.

template<typename T >

std::unique_ptr<TTreeReaderValue<T> > ROOT::Internal::TDF::TColumnValue< T >::fReaderValue {nullptr}

private

Definition at line 134 of file TDFNodes.hxx.

template<typename T >

unsigned int ROOT::Internal::TDF::TColumnValue< T >::fSlot {0}

private

Definition at line 141 of file TDFNodes.hxx.

template<typename T >

TCustomColumnBase* ROOT::Internal::TDF::TColumnValue< T >::fTmpColumn {nullptr}

private

Definition at line 140 of file TDFNodes.hxx.

template<typename T >

T* ROOT::Internal::TDF::TColumnValue< T >::fValuePtr {nullptr}

private

non-temporary columsn and T == std::array_view<U>.

Definition at line 139 of file TDFNodes.hxx.

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

• tree/treeplayer/inc/ROOT/TDFNodes.hxx