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Reference Guide
ROOT::RDF::RTrivialDS Class Referencefinal

Definition at line 21 of file RTrivialDS.hxx.

Public Member Functions

 RTrivialDS (ULong64_t size, bool skipEvenEntries=false)
 
 ~RTrivialDS ()
 
const std::vector< std::string > & GetColumnNames () const
 Returns a reference to the collection of the dataset's column names. More...
 
std::vector< std::pair< ULong64_t, ULong64_t > > GetEntryRanges ()
 Return ranges of entries to distribute to tasks. More...
 
std::string GetLabel ()
 Return a string representation of the datasource type. More...
 
std::string GetTypeName (std::string_view) const
 Type of a column as a string, e.g. More...
 
bool HasColumn (std::string_view colName) const
 Checks if the dataset has a certain column. More...
 
void Initialise ()
 Convenience method called before starting an event-loop. More...
 
bool SetEntry (unsigned int slot, ULong64_t entry)
 Advance the "cursors" returned by GetColumnReaders to the selected entry for a particular slot. More...
 
void SetNSlots (unsigned int nSlots)
 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 void InitSlot (unsigned int, ULong64_t)
 Convenience method called at the start of the data processing associated to a slot. More...
 

Protected Member Functions

std::string AsString ()
 

Private Member Functions

std::vector< void * > GetColumnReadersImpl (std::string_view name, const std::type_info &)
 type-erased vector of pointers to pointers to column values - one per slot More...
 

Private Attributes

std::vector< std::string > fColNames {"col0"}
 
std::vector< ULong64_tfCounter
 
std::vector< ULong64_t * > fCounterAddr
 
std::vector< std::pair< ULong64_t, ULong64_t > > fEntryRanges
 
unsigned int fNSlots = 0U
 
ULong64_t fSize = 0ULL
 
bool fSkipEvenEntries = false
 

Additional Inherited Members

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

#include <ROOT/RTrivialDS.hxx>

Inheritance diagram for ROOT::RDF::RTrivialDS:
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Constructor & Destructor Documentation

◆ RTrivialDS()

ROOT::RDF::RTrivialDS::RTrivialDS ( ULong64_t  size,
bool  skipEvenEntries = false 
)

Definition at line 25 of file RTrivialDS.cxx.

◆ ~RTrivialDS()

ROOT::RDF::RTrivialDS::~RTrivialDS ( )

Definition at line 29 of file RTrivialDS.cxx.

Member Function Documentation

◆ AsString()

std::string ROOT::RDF::RTrivialDS::AsString ( )
inlineprotectedvirtual

Reimplemented from ROOT::RDF::RDataSource.

Definition at line 33 of file RTrivialDS.hxx.

◆ GetColumnNames()

const std::vector< std::string > & ROOT::RDF::RTrivialDS::GetColumnNames ( ) const
virtual

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

Implements ROOT::RDF::RDataSource.

Definition at line 33 of file RTrivialDS.cxx.

◆ GetColumnReadersImpl()

std::vector< void * > ROOT::RDF::RTrivialDS::GetColumnReadersImpl ( std::string_view  name,
const std::type_info &   
)
privatevirtual

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

Implements ROOT::RDF::RDataSource.

Definition at line 11 of file RTrivialDS.cxx.

◆ GetEntryRanges()

std::vector< std::pair< ULong64_t, ULong64_t > > ROOT::RDF::RTrivialDS::GetEntryRanges ( )
virtual

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 48 of file RTrivialDS.cxx.

◆ GetLabel()

std::string ROOT::RDF::RTrivialDS::GetLabel ( )
virtual

Return a string representation of the datasource type.

The returned string will be used by ROOT::RDF::SaveGraph() to represent the datasource in the visualization of the computation graph. Concrete datasources can override the default implementation.

Reimplemented from ROOT::RDF::RDataSource.

Definition at line 87 of file RTrivialDS.cxx.

◆ GetTypeName()

std::string ROOT::RDF::RTrivialDS::GetTypeName ( std::string_view  ) const
virtual

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 43 of file RTrivialDS.cxx.

◆ HasColumn()

bool ROOT::RDF::RTrivialDS::HasColumn ( std::string_view  ) const
virtual

Checks if the dataset has a certain column.

Parameters
[in]columnNameThe name of the column

Implements ROOT::RDF::RDataSource.

Definition at line 38 of file RTrivialDS.cxx.

◆ Initialise()

void ROOT::RDF::RTrivialDS::Initialise ( )
virtual

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 72 of file RTrivialDS.cxx.

◆ SetEntry()

bool ROOT::RDF::RTrivialDS::SetEntry ( unsigned int  slot,
ULong64_t  entry 
)
virtual

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 54 of file RTrivialDS.cxx.

◆ SetNSlots()

void ROOT::RDF::RTrivialDS::SetNSlots ( unsigned int  nSlots)
virtual

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 63 of file RTrivialDS.cxx.

Member Data Documentation

◆ fColNames

std::vector<std::string> ROOT::RDF::RTrivialDS::fColNames {"col0"}
private

Definition at line 27 of file RTrivialDS.hxx.

◆ fCounter

std::vector<ULong64_t> ROOT::RDF::RTrivialDS::fCounter
private

Definition at line 28 of file RTrivialDS.hxx.

◆ fCounterAddr

std::vector<ULong64_t *> ROOT::RDF::RTrivialDS::fCounterAddr
private

Definition at line 29 of file RTrivialDS.hxx.

◆ fEntryRanges

std::vector<std::pair<ULong64_t, ULong64_t> > ROOT::RDF::RTrivialDS::fEntryRanges
private

Definition at line 26 of file RTrivialDS.hxx.

◆ fNSlots

unsigned int ROOT::RDF::RTrivialDS::fNSlots = 0U
private

Definition at line 23 of file RTrivialDS.hxx.

◆ fSize

ULong64_t ROOT::RDF::RTrivialDS::fSize = 0ULL
private

Definition at line 24 of file RTrivialDS.hxx.

◆ fSkipEvenEntries

bool ROOT::RDF::RTrivialDS::fSkipEvenEntries = false
private

Definition at line 25 of file RTrivialDS.hxx.

Libraries for ROOT::RDF::RTrivialDS:
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The documentation for this class was generated from the following files: