An artificial field that transforms an RNTuple column that contains the offset of collections into collection sizes.

It is only used for reading, e.g. as projected field or as an artificial field that provides the "number of" RDF columns for collections (e.g. R_rdf_sizeof_jets for a collection named jets). It is used in the templated RField<RNTupleCardinality<SizeT>> form, which represents the collection sizes either as 32bit unsigned int (std::uint32_t) or as 64bit unsigned int (std::uint64_t).

Definition at line 314 of file RField.hxx.

Public Member Functions
	RCardinalityField (RCardinalityField &&other)=default

	~RCardinalityField () override=default

void	AcceptVisitor (Detail::RFieldVisitor &visitor) const final

const RField< RNTupleCardinality< std::uint32_t > > *	As32Bit () const

const RField< RNTupleCardinality< std::uint64_t > > *	As64Bit () const

RCardinalityField &	operator= (RCardinalityField &&other)=default

Public Member Functions inherited from ROOT::Experimental::RFieldBase
	RFieldBase (const RFieldBase &)=delete

	RFieldBase (RFieldBase &&)=default

	RFieldBase (std::string_view name, std::string_view type, ROOT::ENTupleStructure structure, bool isSimple, std::size_t nRepetitions=0)
	The constructor creates the underlying column objects and connects them to either a sink or a source.

virtual	~RFieldBase ()=default

RSchemaIterator	begin ()

RConstSchemaIterator	begin () const

RValue	BindValue (std::shared_ptr< void > objPtr)
	Creates a value from a memory location with an already constructed object.

RConstSchemaIterator	cbegin () const

RConstSchemaIterator	cend () const

std::unique_ptr< RFieldBase >	Clone (std::string_view newName) const
	Copies the field and its sub fields using a possibly new name and a new, unconnected set of columns.

RBulk	CreateBulk ()
	The returned bulk is initially empty; RBulk::ReadBulk will construct the array of values.

template<>
std::unique_ptr< void, typename RFieldBase::RCreateObjectDeleter< void >::deleter >	CreateObject () const

template<typename T >
std::unique_ptr< T, typename RCreateObjectDeleter< T >::deleter >	CreateObject () const
	Generates an object of the field type and allocates new initialized memory according to the type.

template<>
std::unique_ptr< void, typename ROOT::Experimental::RFieldBase::RCreateObjectDeleter< void >::deleter >	CreateObject () const

RValue	CreateValue ()
	Generates an object of the field type and wraps the created object in a shared pointer and returns it an RValue connected to the field.

RSchemaIterator	end ()

RConstSchemaIterator	end () const

virtual size_t	GetAlignment () const =0
	As a rule of thumb, the alignment is equal to the size of the type.

RColumnRepresentations::Selection_t	GetColumnRepresentatives () const
	Returns the fColumnRepresentative pointee or, if unset (always the case for artificial fields), the field's default representative.

const std::string &	GetDescription () const
	Get the field's description.

const std::string &	GetFieldName () const

virtual std::uint32_t	GetFieldVersion () const
	Indicates an evolution of the mapping scheme from C++ type to columns.

std::size_t	GetNRepetitions () const

ROOT::DescriptorId_t	GetOnDiskId () const

std::uint32_t	GetOnDiskTypeChecksum () const
	Return checksum stored in the field descriptor; only valid after a call to `ConnectPageSource()`, if the field stored a type checksum.

std::uint32_t	GetOnDiskTypeVersion () const
	Return the C++ type version stored in the field descriptor; only valid after a call to `ConnectPageSource()`

const RFieldBase *	GetParent () const

std::string	GetQualifiedFieldName () const
	Returns the field name and parent field names separated by dots ("grandparent.parent.child")

EState	GetState () const

ROOT::ENTupleStructure	GetStructure () const

std::vector< RFieldBase * >	GetSubFields ()

std::vector< const RFieldBase * >	GetSubFields () const

std::uint32_t	GetTraits () const

const std::string &	GetTypeAlias () const

virtual std::uint32_t	GetTypeChecksum () const
	Return the current TClass reported checksum of this class. Only valid if kTraitTypeChecksum is set.

const std::string &	GetTypeName () const

virtual std::uint32_t	GetTypeVersion () const
	Indicates an evolution of the C++ type itself.

virtual size_t	GetValueSize () const =0
	The number of bytes taken by a value of the appropriate type.

bool	HasDefaultColumnRepresentative () const
	Whether or not an explicit column representative was set.

bool	HasReadCallbacks () const

bool	IsArtificial () const

bool	IsSimple () const

RFieldBase &	operator= (const RFieldBase &)=delete

RFieldBase &	operator= (RFieldBase &&)=default

void	SetColumnRepresentatives (const RColumnRepresentations::Selection_t &representatives)
	Fixes a column representative.

void	SetDescription (std::string_view description)

void	SetOnDiskId (ROOT::DescriptorId_t id)

virtual std::vector< RValue >	SplitValue (const RValue &value) const
	Creates the list of direct child values given a value for this field.

Protected Member Functions
	RCardinalityField (std::string_view fieldName, std::string_view typeName)

void	GenerateColumns () final
	Implementations in derived classes should create the backing columns corresponsing to the field type for writing.

void	GenerateColumns (const RNTupleDescriptor &) final
	Implementations in derived classes should create the backing columns corresponsing to the field type for reading.

const RColumnRepresentations &	GetColumnRepresentations () const final
	Implementations in derived classes should return a static RColumnRepresentations object.

Protected Member Functions inherited from ROOT::Experimental::RFieldBase
size_t	AddReadCallback (ReadCallback_t func)
	Set a user-defined function to be called after reading a value, giving a chance to inspect and/or modify the value object.

virtual void	AfterConnectPageSource ()
	Called by `ConnectPageSource()` once connected; derived classes may override this as appropriate.

std::size_t	Append (const void *from)
	Write the given value into columns.

virtual std::size_t	AppendImpl (const void *from)
	Operations on values of complex types, e.g.

void	Attach (std::unique_ptr< RFieldBase > child)
	Add a new subfield to the list of nested fields.

void	AutoAdjustColumnTypes (const ROOT::RNTupleWriteOptions &options)
	When connecting a field to a page sink, the field's default column representation is subject to adjustment according to the write options.

virtual void	BeforeConnectPageSource (Internal::RPageSource &)
	Called by `ConnectPageSource()` before connecting; derived classes may override this as appropriate.

virtual std::unique_ptr< RFieldBase >	CloneImpl (std::string_view newName) const =0
	Called by Clone(), which additionally copies the on-disk ID.

virtual void	CommitClusterImpl ()

virtual void	ConstructValue (void *where) const =0
	Constructs value in a given location of size at least GetValueSize(). Called by the base class' CreateValue().

void *	CreateObjectRawPtr () const
	Factory method for the field's type. The caller owns the returned pointer.

const ColumnRepresentation_t &	EnsureCompatibleColumnTypes (const RNTupleDescriptor &desc, std::uint16_t representationIndex) const
	Returns the on-disk column types found in the provided descriptor for fOnDiskId and the given representation index.

template<typename... ColumnCppTs>
void	GenerateColumnsImpl ()
	For writing, use the currently set column representative.

template<std::uint32_t ColumnIndexT, typename HeadT , typename... TailTs>
void	GenerateColumnsImpl (const ColumnRepresentation_t &representation, std::uint16_t representationIndex)
	Helpers for generating columns.

template<typename... ColumnCppTs>
void	GenerateColumnsImpl (const RNTupleDescriptor &desc)
	For reading, use the on-disk column list.

virtual std::unique_ptr< RDeleter >	GetDeleter () const

virtual RExtraTypeInfoDescriptor	GetExtraTypeInfo () const

virtual bool	HasExtraTypeInfo () const

void	Read (RNTupleLocalIndex localIndex, void *to)
	Populate a single value with data from the field.

void	Read (ROOT::NTupleSize_t globalIndex, void *to)
	Populate a single value with data from the field.

std::size_t	ReadBulk (const RBulkSpec &bulkSpec)
	Returns the number of newly available values, that is the number of bools in bulkSpec.fMaskAvail that flipped from false to true.

virtual std::size_t	ReadBulkImpl (const RBulkSpec &bulkSpec)
	General implementation of bulk read.

virtual void	ReadGlobalImpl (ROOT::NTupleSize_t globalIndex, void *to)

virtual void	ReadInClusterImpl (RNTupleLocalIndex localIndex, void *to)

void	RemoveReadCallback (size_t idx)

Private Member Functions
void	GetCollectionInfo (RNTupleLocalIndex localIndex, RNTupleLocalIndex collectionStart, ROOT::NTupleSize_t size)

void	GetCollectionInfo (ROOT::NTupleSize_t globalIndex, RNTupleLocalIndex collectionStart, ROOT::NTupleSize_t size)

Friends
class	RNTupleCollectionView

Additional Inherited Members
Public Types inherited from ROOT::Experimental::RFieldBase
enum	{ kTraitTriviallyConstructible = 0x01 , kTraitTriviallyDestructible = 0x02 , kTraitMappable = 0x04 , kTraitTypeChecksum = 0x08 , kTraitInvalidField = 0x10 , kTraitEmulatedField = 0x20 , kTraitTrivialType = kTraitTriviallyConstructible \| kTraitTriviallyDestructible }

using	ColumnRepresentation_t = std::vector<ROOT::ENTupleColumnType>

enum class	EState { kUnconnected , kConnectedToSink , kConnectedToSource }
	During its lifetime, a field undergoes the following possible state transitions: More...

using	RConstSchemaIterator = RSchemaIteratorTemplate<true>

using	RSchemaIterator = RSchemaIteratorTemplate<false>

Static Public Member Functions inherited from ROOT::Experimental::RFieldBase
static std::vector< RCheckResult >	Check (const std::string &fieldName, const std::string &typeName)
	Checks if the given type is supported by RNTuple.

static RResult< std::unique_ptr< RFieldBase > >	Create (const std::string &fieldName, const std::string &typeName)
	Factory method to create a field from a certain type given as string.

Static Public Attributes inherited from ROOT::Experimental::RFieldBase
static constexpr std::uint32_t	kInvalidTypeVersion = -1U

Static Protected Member Functions inherited from ROOT::Experimental::RFieldBase
static std::size_t	CallAppendOn (RFieldBase &other, const void *from)
	Allow derived classes to call Append and Read on other (sub) fields.

static void	CallConstructValueOn (const RFieldBase &other, void *where)
	Allow derived classes to call ConstructValue(void *) and GetDeleter on other (sub) fields.

static void *	CallCreateObjectRawPtrOn (RFieldBase &other)

static void	CallReadOn (RFieldBase &other, RNTupleLocalIndex localIndex, void *to)

static void	CallReadOn (RFieldBase &other, ROOT::NTupleSize_t globalIndex, void *to)

static RResult< std::unique_ptr< RFieldBase > >	Create (const std::string &fieldName, const std::string &typeName, const ROOT::RCreateFieldOptions &options, const RNTupleDescriptor *desc, ROOT::DescriptorId_t fieldId)
	Factory method to resurrect a field from the stored on-disk type information.

static std::unique_ptr< RDeleter >	GetDeleterOf (const RFieldBase &other)

static Internal::RColumn *	GetPrincipalColumnOf (const RFieldBase &other)
	Fields may need direct access to the principal column of their sub fields, e.g. in RRVecField::ReadBulk.

Protected Attributes inherited from ROOT::Experimental::RFieldBase
Internal::RColumn *	fAuxiliaryColumn = nullptr
	Some fields have a second column in its column representation.

std::vector< std::unique_ptr< Internal::RColumn > >	fAvailableColumns
	The columns are connected either to a sink or to a source (not to both); they are owned by the field.

std::vector< std::reference_wrapper< const ColumnRepresentation_t > >	fColumnRepresentatives
	Pointers into the static vector GetColumnRepresentations().GetSerializationTypes() when SetColumnRepresentatives is called.

std::uint32_t	fOnDiskTypeChecksum = 0
	TClass checksum cached from the descriptor after a call to `ConnectPageSource()`.

std::uint32_t	fOnDiskTypeVersion = kInvalidTypeVersion
	C++ type version cached from the descriptor after a call to `ConnectPageSource()`

RFieldBase *	fParent
	Sub fields point to their mother field.

Internal::RColumn *	fPrincipalColumn = nullptr
	All fields that have columns have a distinct main column.

std::vector< ReadCallback_t >	fReadCallbacks
	List of functions to be called after reading a value.

std::vector< std::unique_ptr< RFieldBase > >	fSubFields
	Collections and classes own sub fields.

std::uint32_t	fTraits = 0
	Properties of the type that allow for optimizations of collections of that type.

std::string	fTypeAlias
	A typedef or using name that was used when creating the field.

#include <ROOT/RField.hxx>

Inheritance diagram for ROOT::Experimental::RCardinalityField:

[legend]

Constructor & Destructor Documentation

◆ RCardinalityField() [1/2]

ROOT::Experimental::RCardinalityField::RCardinalityField	(	std::string_view	fieldName,
		std::string_view	typeName )

inlineprotected

Definition at line 328 of file RField.hxx.

◆ RCardinalityField() [2/2]

ROOT::Experimental::RCardinalityField::RCardinalityField ( RCardinalityField && other )

default

◆ ~RCardinalityField()

ROOT::Experimental::RCardinalityField::~RCardinalityField ( )

overridedefault

Member Function Documentation

◆ AcceptVisitor()

void ROOT::Experimental::RCardinalityField::AcceptVisitor ( Detail::RFieldVisitor & visitor ) const

finalvirtual

Reimplemented from ROOT::Experimental::RFieldBase.

Definition at line 66 of file RField.cxx.

◆ As32Bit()

const ROOT::Experimental::RField< ROOT::RNTupleCardinality< std::uint32_t > > * ROOT::Experimental::RCardinalityField::As32Bit ( ) const

Definition at line 72 of file RField.cxx.

◆ As64Bit()

const ROOT::Experimental::RField< ROOT::RNTupleCardinality< std::uint64_t > > * ROOT::Experimental::RCardinalityField::As64Bit ( ) const

Definition at line 78 of file RField.cxx.

◆ GenerateColumns() [1/2]

void ROOT::Experimental::RCardinalityField::GenerateColumns ( )

inlinefinalprotectedvirtual

Implementations in derived classes should create the backing columns corresponsing to the field type for writing.

The default implementation does not attach any columns to the field.

Reimplemented from ROOT::Experimental::RFieldBase.

Definition at line 335 of file RField.hxx.

◆ GenerateColumns() [2/2]

void ROOT::Experimental::RCardinalityField::GenerateColumns ( const RNTupleDescriptor & )

finalprotectedvirtual

Implementations in derived classes should create the backing columns corresponsing to the field type for reading.

The default implementation does not attach any columns to the field. The method should check, using the page source and fOnDiskId, if the column types match and throw if they don't.

Reimplemented from ROOT::Experimental::RFieldBase.

Definition at line 61 of file RField.cxx.

◆ GetCollectionInfo() [1/2]

void ROOT::Experimental::RCardinalityField::GetCollectionInfo	(	RNTupleLocalIndex	localIndex,
		RNTupleLocalIndex *	collectionStart,
		ROOT::NTupleSize_t *	size )

inlineprivate

Definition at line 322 of file RField.hxx.

◆ GetCollectionInfo() [2/2]

void ROOT::Experimental::RCardinalityField::GetCollectionInfo	(	ROOT::NTupleSize_t	globalIndex,
		RNTupleLocalIndex *	collectionStart,
		ROOT::NTupleSize_t *	size )

inlineprivate

Definition at line 318 of file RField.hxx.

◆ GetColumnRepresentations()

const ROOT::Experimental::RFieldBase::RColumnRepresentations & ROOT::Experimental::RCardinalityField::GetColumnRepresentations ( ) const

finalprotectedvirtual

Implementations in derived classes should return a static RColumnRepresentations object.

The default implementation does not attach any columns to the field.

Reimplemented from ROOT::Experimental::RFieldBase.

Definition at line 51 of file RField.cxx.

◆ operator=()

RCardinalityField & ROOT::Experimental::RCardinalityField::operator= ( RCardinalityField && other )

default

Friends And Related Symbol Documentation

◆ RNTupleCollectionView

friend class RNTupleCollectionView

friend

Definition at line 315 of file RField.hxx.

Libraries for ROOT::Experimental::RCardinalityField:

[legend]

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

tree/ntuple/v7/inc/ROOT/RField.hxx
tree/ntuple/v7/src/RField.cxx

Public Member Functions

Protected Member Functions

Private Member Functions

Friends

Additional Inherited Members

Constructor & Destructor Documentation

◆ RCardinalityField() [1/2]

◆ RCardinalityField() [2/2]

◆ ~RCardinalityField()

Member Function Documentation

◆ AcceptVisitor()

◆ As32Bit()

◆ As64Bit()

◆ GenerateColumns() [1/2]

◆ GenerateColumns() [2/2]

◆ GetCollectionInfo() [1/2]

◆ GetCollectionInfo() [2/2]

◆ GetColumnRepresentations()

◆ operator=()

Friends And Related Symbol Documentation

◆ RNTupleCollectionView