Logo ROOT   6.21/01
Reference Guide
ROOT::Experimental::RNTupleDS Class Referencefinal

Definition at line 35 of file RNTupleDS.hxx.

Public Member Functions

 RNTupleDS (std::unique_ptr< ROOT::Experimental::RNTupleReader > ntuple)
 
 ~RNTupleDS ()=default
 
const std::vector< std::string > & GetColumnNames () const final
 Returns a reference to the collection of the dataset's column names. More...
 
std::vector< std::pair< ULong64_t, ULong64_t > > GetEntryRanges () final
 Return ranges of entries to distribute to tasks. More...
 
std::string GetTypeName (std::string_view colName) const final
 Type of a column as a string, e.g. More...
 
bool HasColumn (std::string_view colName) const final
 Checks if the dataset has a certain column. More...
 
void Initialise () final
 Convenience method called before starting an event-loop. More...
 
bool SetEntry (unsigned int slot, ULong64_t entry) final
 Advance the "cursors" returned by GetColumnReaders to the selected entry for a particular slot. More...
 
void SetNSlots (unsigned int nSlots) final
 Inform RDataSource of the number of processing slots (i.e. More...
 
- Public Member Functions inherited from ROOT::RDF::RDataSource
virtual ~RDataSource ()=default
 
virtual void Finalise ()
 Convenience method called after concluding an event-loop. More...
 
virtual void FinaliseSlot (unsigned int)
 Convenience method called at the end of the data processing associated to a slot. More...
 
template<typename T >
std::vector< T ** > GetColumnReaders (std::string_view columnName)
 Called at most once per column by RDF. More...
 
virtual std::string GetLabel ()
 Return a string representation of the datasource type. More...
 
virtual void InitSlot (unsigned int, ULong64_t)
 Convenience method called at the start of the data processing associated to a slot. More...
 

Protected Member Functions

Record_t GetColumnReadersImpl (std::string_view name, const std::type_info &) final
 type-erased vector of pointers to pointers to column values - one per slot More...
 
- Protected Member Functions inherited from ROOT::RDF::RDataSource
virtual std::string AsString ()
 

Private Attributes

std::vector< std::string > fColumnNames
 
std::vector< std::string > fColumnTypes
 
std::vector< std::unique_ptr< ROOT::Experimental::REntry > > fEntries
 
bool fHasSeenAllRanges = false
 
unsigned fNSlots = 0
 
std::vector< std::unique_ptr< ROOT::Experimental::RNTupleReader > > fReaders
 Clones of the first reader, one for each slot. More...
 
std::vector< std::vector< void * > > fValuePtrs
 The raw pointers wrapped by the RValue items of fEntries. More...
 

Additional Inherited Members

- Protected Types inherited from ROOT::RDF::RDataSource
using Record_t = std::vector< void * >
 

#include <ROOT/RNTupleDS.hxx>

Inheritance diagram for ROOT::Experimental::RNTupleDS:
[legend]

Constructor & Destructor Documentation

◆ RNTupleDS()

ROOT::Experimental::RNTupleDS::RNTupleDS ( std::unique_ptr< ROOT::Experimental::RNTupleReader ntuple)
explicit

Definition at line 30 of file RNTupleDS.cxx.

◆ ~RNTupleDS()

ROOT::Experimental::RNTupleDS::~RNTupleDS ( )
default

Member Function Documentation

◆ GetColumnNames()

const std::vector< std::string > & ROOT::Experimental::RNTupleDS::GetColumnNames ( ) const
finalvirtual

Returns a reference to the collection of the dataset's column names.

Implements ROOT::RDF::RDataSource.

Definition at line 42 of file RNTupleDS.cxx.

◆ GetColumnReadersImpl()

RDF::RDataSource::Record_t ROOT::Experimental::RNTupleDS::GetColumnReadersImpl ( std::string_view  name,
const std::type_info &   
)
finalprotectedvirtual

type-erased vector of pointers to pointers to column values - one per slot

Implements ROOT::RDF::RDataSource.

Definition at line 48 of file RNTupleDS.cxx.

◆ GetEntryRanges()

std::vector< std::pair< ULong64_t, ULong64_t > > ROOT::Experimental::RNTupleDS::GetEntryRanges ( )
finalvirtual

Return ranges of entries to distribute to tasks.

They are required to be contiguous intervals with no entries skipped. Supposing a dataset with nEntries, the intervals must start at 0 and end at nEntries, e.g. [0-5],[5-10] for 10 entries. This function will be invoked repeatedly by RDataFrame as it needs additional entries to process. The same entry range should not be returned more than once. Returning an empty collection of ranges signals to RDataFrame that the processing can stop.

Implements ROOT::RDF::RDataSource.

Definition at line 68 of file RNTupleDS.cxx.

◆ GetTypeName()

std::string ROOT::Experimental::RNTupleDS::GetTypeName ( std::string_view  ) const
finalvirtual

Type of a column as a string, e.g.

GetTypeName("x") == "double". Required for jitting e.g. df.Filter("x>0").

Parameters
[in]columnNameThe name of the column

Implements ROOT::RDF::RDataSource.

Definition at line 91 of file RNTupleDS.cxx.

◆ HasColumn()

bool ROOT::Experimental::RNTupleDS::HasColumn ( std::string_view  ) const
finalvirtual

Checks if the dataset has a certain column.

Parameters
[in]columnNameThe name of the column

Implements ROOT::RDF::RDataSource.

Definition at line 99 of file RNTupleDS.cxx.

◆ Initialise()

void ROOT::Experimental::RNTupleDS::Initialise ( )
finalvirtual

Convenience method called before starting an event-loop.

This method might be called multiple times over the lifetime of a RDataSource, since users can run multiple event-loops with the same RDataFrame. Ideally, Initialise should set the state of the RDataSource so that multiple identical event-loops will produce identical results.

Reimplemented from ROOT::RDF::RDataSource.

Definition at line 106 of file RNTupleDS.cxx.

◆ SetEntry()

bool ROOT::Experimental::RNTupleDS::SetEntry ( unsigned int  slot,
ULong64_t  entry 
)
finalvirtual

Advance the "cursors" returned by GetColumnReaders to the selected entry for a particular slot.

Parameters
[in]slotThe data processing slot that needs to be considered
[in]entryThe entry which needs to be pointed to by the reader pointers Slots are adopted to accommodate parallel data processing. Different workers will loop over different ranges and will be labelled by different "slot" values. Returns true if the entry has to be processed, false otherwise.

Implements ROOT::RDF::RDataSource.

Definition at line 62 of file RNTupleDS.cxx.

◆ SetNSlots()

void ROOT::Experimental::RNTupleDS::SetNSlots ( unsigned int  nSlots)
finalvirtual

Inform RDataSource of the number of processing slots (i.e.

worker threads) used by the associated RDataFrame. Slots numbers are used to simplify parallel execution: RDataFrame guarantees that different threads will always pass different slot values when calling methods concurrently.

Implements ROOT::RDF::RDataSource.

Definition at line 112 of file RNTupleDS.cxx.

Member Data Documentation

◆ fColumnNames

std::vector<std::string> ROOT::Experimental::RNTupleDS::fColumnNames
private

Definition at line 43 of file RNTupleDS.hxx.

◆ fColumnTypes

std::vector<std::string> ROOT::Experimental::RNTupleDS::fColumnTypes
private

Definition at line 44 of file RNTupleDS.hxx.

◆ fEntries

std::vector<std::unique_ptr<ROOT::Experimental::REntry> > ROOT::Experimental::RNTupleDS::fEntries
private

Definition at line 38 of file RNTupleDS.hxx.

◆ fHasSeenAllRanges

bool ROOT::Experimental::RNTupleDS::fHasSeenAllRanges = false
private

Definition at line 42 of file RNTupleDS.hxx.

◆ fNSlots

unsigned ROOT::Experimental::RNTupleDS::fNSlots = 0
private

Definition at line 41 of file RNTupleDS.hxx.

◆ fReaders

std::vector<std::unique_ptr<ROOT::Experimental::RNTupleReader> > ROOT::Experimental::RNTupleDS::fReaders
private

Clones of the first reader, one for each slot.

Definition at line 37 of file RNTupleDS.hxx.

◆ fValuePtrs

std::vector<std::vector<void*> > ROOT::Experimental::RNTupleDS::fValuePtrs
private

The raw pointers wrapped by the RValue items of fEntries.

Definition at line 40 of file RNTupleDS.hxx.


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