Namespaces
namespace	Experimental

namespace	Internal

Classes
class	RArrowDS
	RDataFrame data source class to interface with Apache Arrow. More...

class	RCsvDS
	RDataFrame data source class for reading CSV files. More...

class	RCutFlowReport

class	RDataSource
	RDataSource defines an API that RDataFrame can use to read arbitrary data formats. More...

class	RDFDescription
	A DFDescription contains useful information about a given RDataFrame computation graph. More...

class	RDFTypeNameGetter
	Helper to get the contents of a given column. More...

class	RDisplay
	This class is the textual representation of the content of a columnar dataset. More...

class	RInterface
	The public interface to the RDataFrame federation of classes. More...

class	RInterfaceBase

class	RLazyDS
	A RDataSource implementation which is built on top of result proxies. More...

class	RResultHandle
	A type-erased version of RResultPtr and RResultMap. More...

class	RResultPtr
	Smart pointer for the return type of actions. More...

class	RSampleInfo
	This type represents a sample identifier, to be used in conjunction with RDataFrame features such as DefinePerSample() and per-sample callbacks. More...

struct	RSnapshotOptions
	A collection of options to steer the creation of the dataset on file. More...

class	RSqliteDS
	RSqliteDS is an RDF data source implementation for SQL result sets from sqlite3 files. More...

class	RTrivialDS
	A simple data-source implementation, for demo purposes. More...

class	RVariationsDescription
	A descriptor for the systematic variations known to a given RDataFrame node. More...

class	TCutInfo

class	TH1DModel
	A struct which stores the parameters of a TH1D. More...

class	TH2DModel
	A struct which stores the parameters of a TH2D. More...

class	TH3DModel
	A struct which stores the parameters of a TH3D. More...

class	THnDModel
	A struct which stores the parameters of a THnD. More...

class	TProfile1DModel
	A struct which stores the parameters of a TProfile. More...

class	TProfile2DModel
	A struct which stores the parameters of a TProfile2D. More...

class	VerifyValidColumnType
	Helper to determine if a given Column is a supported type. More...

Typedefs
using	ColumnNames_t = std::vector< std::string >

using	RNode = RInterface<::ROOT::Detail::RDF::RNodeBase, void >

using	SampleCallback_t = std::function< void(unsigned int, const ROOT::RDF::RSampleInfo &)>
	The type of a data-block callback, registered with an RDataFrame computation graph via e.g.

template<typename T >
using	TResultProxy = RResultPtr< T >

Functions
template<typename NodeType >
RNode	AsRNode (NodeType node)
	Cast a RDataFrame node to the common type ROOT::RDF::RNode.

RDataFrame	FromArrow (std::shared_ptr< arrow::Table > table, std::vector< std::string > const &columnNames)
	Factory method to create a Apache Arrow RDataFrame.

RDataFrame	FromCSV (std::string_view fileName, bool readHeaders=true, char delimiter=',', Long64_t linesChunkSize=-1LL, std::unordered_map< std::string, char > &&colTypes={})
	Factory method to create a CSV RDataFrame.

RDataFrame	FromSqlite (std::string_view fileName, std::string_view query)
	Factory method to create a SQlite RDataFrame.

template<typename T >
std::shared_ptr< arrow::ChunkedArray >	getData (T p)

int	getNRecords (std::shared_ptr< arrow::Table > &table, std::vector< std::string > &columnNames)

template<typename... ColumnTypes>
RDataFrame	MakeLazyDataFrame (std::pair< std::string, RResultPtr< std::vector< ColumnTypes > > > &&... colNameProxyPairs)
	Factory method to create a Lazy RDataFrame.

RInterface< RDFDetail::RLoopManager >	MakeTrivialDataFrame ()
	Make a RDF wrapping a RTrivialDS with infinite entries, for demo purposes.

RInterface< RDFDetail::RLoopManager >	MakeTrivialDataFrame (ULong64_t size, bool skipEvenEntries=false)
	Make a RDF wrapping a RTrivialDS with the specified amount of entries.

template<typename F , typename Args = typename ROOT::TypeTraits::CallableTraits<std::decay_t<F>>::arg_types_nodecay, typename Ret = typename ROOT::TypeTraits::CallableTraits<std::decay_t<F>>::ret_type>
auto	Not (F &&f) -> decltype(RDFInternal::NotHelper(Args(), std::forward< F >(f)))
	Given a callable with signature bool(T1, T2, ...) return a callable with same signature that returns the negated result.

template<class T1 , class T2 >
bool	operator!= (const RResultPtr< T1 > &lhs, const RResultPtr< T2 > &rhs)

template<class T1 >
bool	operator!= (const RResultPtr< T1 > &lhs, std::nullptr_t rhs)

template<class T1 >
bool	operator!= (std::nullptr_t lhs, const RResultPtr< T1 > &rhs)

std::ostream &	operator<< (std::ostream &os, const RDFDescription &description)

template<class T1 , class T2 >
bool	operator== (const RResultPtr< T1 > &lhs, const RResultPtr< T2 > &rhs)

template<class T1 >
bool	operator== (const RResultPtr< T1 > &lhs, std::nullptr_t rhs)

template<class T1 >
bool	operator== (std::nullptr_t lhs, const RResultPtr< T1 > &rhs)

template<std::size_t N, typename T , typename F >
auto	PassAsVec (F &&f) -> RDFInternal::PassAsVecHelper< std::make_index_sequence< N >, T, F >
	PassAsVec is a callable generator that allows passing N variables of type T to a function as a single collection.

unsigned int	RunGraphs (std::vector< RResultHandle > handles)
	Trigger the event loop of multiple RDataFrames concurrently.

template<typename NodeType >
std::string	SaveGraph (NodeType node)
	Create a graphviz representation of the dataframe computation graph, return it as a string.

template<typename NodeType >
void	SaveGraph (NodeType node, const std::string &outputFile)
	Create a graphviz representation of the dataframe computation graph, write it to the specified file.

void	splitInEqualRanges (std::vector< std::pair< ULong64_t, ULong64_t > > &ranges, int nRecords, unsigned int nSlots)

Typedef Documentation

◆ ColumnNames_t

typedef std::vector< std::string > ROOT::RDF::ColumnNames_t

Definition at line 35 of file RInterfaceBase.hxx.

◆ RNode

typedef RInterface<::ROOT::Detail::RDF::RNodeBase, void > ROOT::RDF::RNode

Definition at line 57 of file InterfaceUtils.hxx.

◆ SampleCallback_t

using ROOT::RDF::SampleCallback_t = typedef std::function<void(unsigned int, const ROOT::RDF::RSampleInfo &)>

The type of a data-block callback, registered with an RDataFrame computation graph via e.g.

DefinePerSample() or by certain actions (e.g. Snapshot()).

Definition at line 134 of file RSampleInfo.hxx.

◆ TResultProxy

template<typename T >

using ROOT::RDF::TResultProxy = typedef RResultPtr<T>

Definition at line 18 of file TResultProxy.hxx.

Function Documentation

◆ AsRNode()

template<typename NodeType >

RNode ROOT::RDF::AsRNode ( NodeType node )

Cast a RDataFrame node to the common type ROOT::RDF::RNode.

Parameters

[in] node Any node of a RDataFrame graph

Definition at line 158 of file RDFHelpers.hxx.

◆ FromArrow()

RDataFrame ROOT::RDF::FromArrow	(	std::shared_ptr< arrow::Table >	table,
		std::vector< std::string > const &	columnNames
	)

Factory method to create a Apache Arrow RDataFrame.

Creates a RDataFrame using an arrow::Table as input.

Parameters

[in]	table	an apache::arrow table to use as a source / to observe.
[in]	columnNames	the name of the columns to use In case columnNames is empty, we use all the columns found in the table

Definition at line 606 of file RArrowDS.cxx.

◆ FromCSV()

RDataFrame ROOT::RDF::FromCSV	(	std::string_view	fileName,
		bool	readHeaders = `true`,
		char	delimiter = `','`,
		Long64_t	linesChunkSize = `-1LL`,
		std::unordered_map< std::string, char > &&	colTypes = `{}`
	)

Factory method to create a CSV RDataFrame.

Parameters

[in]	fileName	Path of the CSV file.
[in]	readHeaders	`true` if the CSV file contains headers as first row, `false` otherwise (default `true`).
[in]	delimiter	Delimiter character (default ',').
[in]	linesChunkSize	bunch of lines to read, use -1 to read all
[in]	colTypes	Allow user to specify custom column types, accepts an unordered map with keys being column type, values being type alias ('O' for boolean, 'D' for double, 'L' for Long64_t, 'T' for std::string)

Definition at line 558 of file RCsvDS.cxx.

◆ FromSqlite()

RDataFrame ROOT::RDF::FromSqlite	(	std::string_view	fileName,
		std::string_view	query
	)

Factory method to create a SQlite RDataFrame.

Parameters

[in]	fileName	Path of the sqlite file.
[in]	query	SQL query that defines the data set.

Definition at line 543 of file RSqliteDS.cxx.

◆ getData()

template<typename T >

std::shared_ptr< arrow::ChunkedArray > ROOT::RDF::getData ( T p )

Definition at line 542 of file RArrowDS.cxx.

◆ getNRecords()

int ROOT::RDF::getNRecords	(	std::shared_ptr< arrow::Table > &	table,
		std::vector< std::string > &	columnNames
	)

Definition at line 535 of file RArrowDS.cxx.

◆ MakeLazyDataFrame()

template<typename... ColumnTypes>

RDataFrame ROOT::RDF::MakeLazyDataFrame ( std::pair< std::string, RResultPtr< std::vector< ColumnTypes > > > &&... colNameProxyPairs )

Factory method to create a Lazy RDataFrame.

Parameters

[in] colNameProxyPairs the series of pairs to describe the columns of the data source, first element of the pair is the name of the column and the second is the RResultPtr to the column in the parent data frame.

Definition at line 29 of file RLazyDS.hxx.

◆ MakeTrivialDataFrame() [1/2]

RInterface< RDFDetail::RLoopManager > ROOT::RDF::MakeTrivialDataFrame ( )

Make a RDF wrapping a RTrivialDS with infinite entries, for demo purposes.

Definition at line 130 of file RTrivialDS.cxx.

◆ MakeTrivialDataFrame() [2/2]

RInterface< RDFDetail::RLoopManager > ROOT::RDF::MakeTrivialDataFrame	(	ULong64_t	size,
		bool	skipEvenEntries = `false`
	)

Make a RDF wrapping a RTrivialDS with the specified amount of entries.

Constructing an RDataFrame as RDataFrame(nEntries) is a superior alternative. If size is std::numeric_limits<ULong64_t>::max(), this acts as an infinite data-source: it returns entries from GetEntryRanges forever or until a Range stops the event loop (for test purposes).

Definition at line 123 of file RTrivialDS.cxx.

◆ Not()

template<typename F , typename Args = typename ROOT::TypeTraits::CallableTraits<std::decay_t<F>>::arg_types_nodecay, typename Ret = typename ROOT::TypeTraits::CallableTraits<std::decay_t<F>>::ret_type>

auto ROOT::RDF::Not ( F && f ) -> decltype(RDFInternal::NotHelper(Args(), std::forward<F>(f)))

Given a callable with signature bool(T1, T2, ...) return a callable with same signature that returns the negated result.

The callable must have one single non-template definition of operator(). This is a limitation with respect to std::not_fn, required for interoperability with RDataFrame.

Definition at line 83 of file RDFHelpers.hxx.

◆ operator!=() [1/3]

template<class T1 , class T2 >

bool ROOT::RDF::operator!=	(	const RResultPtr< T1 > &	lhs,
		const RResultPtr< T2 > &	rhs
	)

Definition at line 407 of file RResultPtr.hxx.

◆ operator!=() [2/3]

template<class T1 >

bool ROOT::RDF::operator!=	(	const RResultPtr< T1 > &	lhs,
		std::nullptr_t	rhs
	)

Definition at line 425 of file RResultPtr.hxx.

◆ operator!=() [3/3]

template<class T1 >

bool ROOT::RDF::operator!=	(	std::nullptr_t	lhs,
		const RResultPtr< T1 > &	rhs
	)

Definition at line 431 of file RResultPtr.hxx.

◆ operator<<()

std::ostream & ROOT::RDF::operator<<	(	std::ostream &	os,
		const RDFDescription &	description
	)

Definition at line 37 of file RDFDescription.cxx.

◆ operator==() [1/3]

template<class T1 , class T2 >

bool ROOT::RDF::operator==	(	const RResultPtr< T1 > &	lhs,
		const RResultPtr< T2 > &	rhs
	)

Definition at line 401 of file RResultPtr.hxx.

◆ operator==() [2/3]

template<class T1 >

bool ROOT::RDF::operator==	(	const RResultPtr< T1 > &	lhs,
		std::nullptr_t	rhs
	)

Definition at line 413 of file RResultPtr.hxx.

◆ operator==() [3/3]

template<class T1 >

bool ROOT::RDF::operator==	(	std::nullptr_t	lhs,
		const RResultPtr< T1 > &	rhs
	)

Definition at line 419 of file RResultPtr.hxx.

◆ PassAsVec()

template<std::size_t N, typename T , typename F >

auto ROOT::RDF::PassAsVec ( F && f ) -> RDFInternal::PassAsVecHelper<std::make_index_sequence<N>, T, F>

PassAsVec is a callable generator that allows passing N variables of type T to a function as a single collection.

PassAsVec<N, T>(func) returns a callable that takes N arguments of type T, passes them down to function func as an initializer list {t1, t2, t3,..., tN} and returns whatever f({t1, t2, t3, ..., tN}) returns.

Note that for this to work with RDataFrame the type of all columns that the callable is applied to must be exactly T. Example usage together with RDataFrame ("varX" columns must all be float variables):

bool myVecFunc(std::vector<float> args);

df.Filter(PassAsVec<3, float>(myVecFunc), {"var1", "var2", "var3"});

Definition at line 103 of file RDFHelpers.hxx.

◆ RunGraphs()

unsigned int ROOT::RDF::RunGraphs ( std::vector< RResultHandle > handles )

Trigger the event loop of multiple RDataFrames concurrently.

Parameters

[in] handles A vector of RResultHandles

Returns: The number of distinct computation graphs that have been processed

This function triggers the event loop of all computation graphs which relate to the given RResultHandles. The advantage compared to running the event loop implicitly by accessing the RResultPtr is that the event loops will run concurrently. Therefore, the overall computation of all results is generally more efficient. It should be noted that user-defined operations (e.g., Filters and Defines) of the different RDataFrame graphs are assumed to be safe to call concurrently.

ROOT::RDataFrame df1("tree1", "file1.root");
auto r1 = df1.Histo1D("var1");
 
ROOT::RDataFrame df2("tree2", "file2.root");
auto r2 = df2.Sum("var2");
 
// RResultPtr -> RResultHandle conversion is automatic
ROOT::RDF::RunGraphs({r1, r2});

Definition at line 66 of file RDFHelpers.cxx.

◆ SaveGraph() [1/2]

template<typename NodeType >

std::string ROOT::RDF::SaveGraph ( NodeType node )

Create a graphviz representation of the dataframe computation graph, return it as a string.

Parameters

[in] node any node of the graph. Called on the head (first) node, it prints the entire graph. Otherwise, only the branch the node belongs to.

The output can be displayed with a command akin to dot -Tpng output.dot > output.png && open output.png.

Note that "hanging" Defines, i.e. Defines without downstream nodes, will not be displayed by SaveGraph as they are effectively optimized away from the computation graph.

Note that SaveGraph is not thread-safe and must not be called concurrently from different threads.

Definition at line 120 of file RDFHelpers.hxx.

◆ SaveGraph() [2/2]

template<typename NodeType >

void ROOT::RDF::SaveGraph	(	NodeType	node,
		const std::string &	outputFile
	)

Create a graphviz representation of the dataframe computation graph, write it to the specified file.

Parameters

[in]	node	any node of the graph. Called on the head (first) node, it prints the entire graph. Otherwise, only the branch the node belongs to.
[in]	outputFile	file where to save the representation.

The output can be displayed with a command akin to dot -Tpng output.dot > output.png && open output.png.

Note that "hanging" Defines, i.e. Defines without downstream nodes, will not be displayed by SaveGraph as they are effectively optimized away from the computation graph.

Note that SaveGraph is not thread-safe and must not be called concurrently from different threads.

Definition at line 139 of file RDFHelpers.hxx.

◆ splitInEqualRanges()

void ROOT::RDF::splitInEqualRanges	(	std::vector< std::pair< ULong64_t, ULong64_t > > &	ranges,
		int	nRecords,
		unsigned int	nSlots
	)

Definition at line 519 of file RArrowDS.cxx.

Namespaces

Classes

Typedefs

Functions

Typedef Documentation

◆ ColumnNames_t

◆ RNode

◆ SampleCallback_t

◆ TResultProxy

Function Documentation

◆ AsRNode()

◆ FromArrow()

◆ FromCSV()

◆ FromSqlite()

◆ getData()

◆ getNRecords()

◆ MakeLazyDataFrame()

◆ MakeTrivialDataFrame() [1/2]

◆ MakeTrivialDataFrame() [2/2]

◆ Not()

◆ operator!=() [1/3]

◆ operator!=() [2/3]

◆ operator!=() [3/3]

◆ operator<<()

◆ operator==() [1/3]

◆ operator==() [2/3]

◆ operator==() [3/3]

◆ PassAsVec()

◆ RunGraphs()

◆ SaveGraph() [1/2]

◆ SaveGraph() [2/2]

◆ splitInEqualRanges()