ROOT::RFieldDescriptor Class Reference

Metadata stored for every field of an ntuple.

Definition at line 78 of file RNTupleDescriptor.hxx.

Public Member Functions
	RFieldDescriptor ()=default
	RFieldDescriptor (const RFieldDescriptor &other)=delete
	RFieldDescriptor (RFieldDescriptor &&other)=default
RFieldDescriptor	Clone () const
	Get a copy of the descriptor.
std::unique_ptr< ROOT::RFieldBase >	CreateField (const RNTupleDescriptor &ntplDesc, const ROOT::RCreateFieldOptions &options={}) const
	In general, we create a field simply from the C++ type name.
std::uint32_t	GetColumnCardinality () const
const std::string &	GetFieldDescription () const
const std::string &	GetFieldName () const
std::uint32_t	GetFieldVersion () const
ROOT::DescriptorId_t	GetId () const
const std::vector< ROOT::DescriptorId_t > &	GetLinkIds () const
const std::vector< ROOT::DescriptorId_t > &	GetLogicalColumnIds () const
std::uint64_t	GetNRepetitions () const
ROOT::DescriptorId_t	GetParentId () const
ROOT::DescriptorId_t	GetProjectionSourceId () const
ROOT::ENTupleStructure	GetStructure () const
const std::string &	GetTypeAlias () const
std::optional< std::uint32_t >	GetTypeChecksum () const
const std::string &	GetTypeName () const
std::uint32_t	GetTypeVersion () const
bool	IsCustomClass () const
	Tells if the field describes a user-defined class rather than a fundamental type, a collection, or one of the natively supported stdlib classes.
bool	IsProjectedField () const
RFieldDescriptor &	operator= (const RFieldDescriptor &other)=delete
RFieldDescriptor &	operator= (RFieldDescriptor &&other)=default
bool	operator== (const RFieldDescriptor &other) const

Private Attributes
std::uint32_t	fColumnCardinality = 0
	The number of columns in the column representations of the field.
std::string	fFieldDescription
	Free text set by the user.
ROOT::DescriptorId_t	fFieldId = ROOT::kInvalidDescriptorId
std::string	fFieldName
	The leaf name, not including parent fields.
std::uint32_t	fFieldVersion = 0
	The version of the C++-type-to-column translation mechanics.
std::vector< ROOT::DescriptorId_t >	fLinkIds
	The pointers in the other direction from parent to children.
std::vector< ROOT::DescriptorId_t >	fLogicalColumnIds
	The ordered list of columns attached to this field: first by representation index then by column index.
std::uint64_t	fNRepetitions = 0
	The number of elements per entry for fixed-size arrays.
ROOT::DescriptorId_t	fParentId = ROOT::kInvalidDescriptorId
	Establishes sub field relationships, such as classes and collections.
ROOT::DescriptorId_t	fProjectionSourceId = ROOT::kInvalidDescriptorId
	For projected fields, the source field ID.
ROOT::ENTupleStructure	fStructure = ROOT::ENTupleStructure::kInvalid
	The structural information carried by this field in the data model tree.
std::string	fTypeAlias
	A typedef or using directive that resolved to the type name during field creation.
std::optional< std::uint32_t >	fTypeChecksum
	For custom classes, we store the ROOT TClass reported checksum to facilitate the use of I/O rules that identify types by their checksum.
std::string	fTypeName
	The C++ type that was used when writing the field.
std::uint32_t	fTypeVersion = 0
	The version of the C++ type itself.

Friends
class	Internal::RFieldDescriptorBuilder
class	Internal::RNTupleDescriptorBuilder

#include <ROOT/RNTupleDescriptor.hxx>

Constructor & Destructor Documentation

RFieldDescriptor() [1/3]

ROOT::RFieldDescriptor::RFieldDescriptor ( )

default

RFieldDescriptor() [2/3]

ROOT::RFieldDescriptor::RFieldDescriptor ( const RFieldDescriptor & other )

delete

RFieldDescriptor() [3/3]

ROOT::RFieldDescriptor::RFieldDescriptor ( RFieldDescriptor && other )

default

Member Function Documentation

Clone()

ROOT::RFieldDescriptor ROOT::RFieldDescriptor::Clone

(

)

const

Get a copy of the descriptor.

Definition at line 50 of file RNTupleDescriptor.cxx.

CreateField()

std::unique_ptr< ROOT::RFieldBase > ROOT::RFieldDescriptor::CreateField	(	const RNTupleDescriptor &	ntplDesc,
		const ROOT::RCreateFieldOptions &	options = {} ) const

In general, we create a field simply from the C++ type name.

For untyped fields, however, we potentially need access to sub fields, which is provided by the ntuple descriptor argument.

Definition at line 72 of file RNTupleDescriptor.cxx.

GetColumnCardinality()

std::uint32_t ROOT::RFieldDescriptor::GetColumnCardinality ( ) const

inline

Definition at line 146 of file RNTupleDescriptor.hxx.

GetFieldDescription()

const std::string & ROOT::RFieldDescriptor::GetFieldDescription ( ) const

inline

Definition at line 137 of file RNTupleDescriptor.hxx.

GetFieldName()

const std::string & ROOT::RFieldDescriptor::GetFieldName ( ) const

inline

Definition at line 136 of file RNTupleDescriptor.hxx.

GetFieldVersion()

std::uint32_t ROOT::RFieldDescriptor::GetFieldVersion ( ) const

inline

Definition at line 134 of file RNTupleDescriptor.hxx.

GetId()

ROOT::DescriptorId_t ROOT::RFieldDescriptor::GetId ( ) const

inline

Definition at line 133 of file RNTupleDescriptor.hxx.

GetLinkIds()

const std::vector< ROOT::DescriptorId_t > & ROOT::RFieldDescriptor::GetLinkIds ( ) const

inline

Definition at line 144 of file RNTupleDescriptor.hxx.

GetLogicalColumnIds()

const std::vector< ROOT::DescriptorId_t > & ROOT::RFieldDescriptor::GetLogicalColumnIds ( ) const

inline

Definition at line 145 of file RNTupleDescriptor.hxx.

GetNRepetitions()

std::uint64_t ROOT::RFieldDescriptor::GetNRepetitions ( ) const

inline

Definition at line 140 of file RNTupleDescriptor.hxx.

GetParentId()

ROOT::DescriptorId_t ROOT::RFieldDescriptor::GetParentId ( ) const

inline

Definition at line 142 of file RNTupleDescriptor.hxx.

GetProjectionSourceId()

ROOT::DescriptorId_t ROOT::RFieldDescriptor::GetProjectionSourceId ( ) const

inline

Definition at line 143 of file RNTupleDescriptor.hxx.

GetStructure()

ROOT::ENTupleStructure ROOT::RFieldDescriptor::GetStructure ( ) const

inline

Definition at line 141 of file RNTupleDescriptor.hxx.

GetTypeAlias()

const std::string & ROOT::RFieldDescriptor::GetTypeAlias ( ) const

inline

Definition at line 139 of file RNTupleDescriptor.hxx.

GetTypeChecksum()

std::optional< std::uint32_t > ROOT::RFieldDescriptor::GetTypeChecksum ( ) const

inline

Definition at line 147 of file RNTupleDescriptor.hxx.

GetTypeName()

const std::string & ROOT::RFieldDescriptor::GetTypeName ( ) const

inline

Definition at line 138 of file RNTupleDescriptor.hxx.

GetTypeVersion()

std::uint32_t ROOT::RFieldDescriptor::GetTypeVersion ( ) const

inline

Definition at line 135 of file RNTupleDescriptor.hxx.

IsCustomClass()

bool ROOT::RFieldDescriptor::IsCustomClass

(

)

const

Tells if the field describes a user-defined class rather than a fundamental type, a collection, or one of the natively supported stdlib classes.

The dictionary does not need to be available for this method.

Definition at line 153 of file RNTupleDescriptor.cxx.

IsProjectedField()

bool ROOT::RFieldDescriptor::IsProjectedField ( ) const

inline

Definition at line 148 of file RNTupleDescriptor.hxx.

operator=() [1/2]

RFieldDescriptor & ROOT::RFieldDescriptor::operator= ( const RFieldDescriptor & other )

delete

operator=() [2/2]

RFieldDescriptor & ROOT::RFieldDescriptor::operator= ( RFieldDescriptor && other )

default

operator==()

bool ROOT::RFieldDescriptor::operator==

(

const RFieldDescriptor &

other

)

const

Definition at line 40 of file RNTupleDescriptor.cxx.

Friends And Related Symbol Documentation

Internal::RFieldDescriptorBuilder

friend class Internal::RFieldDescriptorBuilder

friend

Definition at line 80 of file RNTupleDescriptor.hxx.

Internal::RNTupleDescriptorBuilder

friend class Internal::RNTupleDescriptorBuilder

friend

Definition at line 79 of file RNTupleDescriptor.hxx.

Member Data Documentation

fColumnCardinality

std::uint32_t ROOT::RFieldDescriptor::fColumnCardinality = 0

private

The number of columns in the column representations of the field.

The column cardinality helps to navigate the list of logical column ids. For example, the second column of the third column representation is fLogicalColumnIds[2 * fColumnCardinality + 1]

Definition at line 110 of file RNTupleDescriptor.hxx.

fFieldDescription

std::string ROOT::RFieldDescriptor::fFieldDescription

private

Free text set by the user.

Definition at line 91 of file RNTupleDescriptor.hxx.

fFieldId

ROOT::DescriptorId_t ROOT::RFieldDescriptor::fFieldId = ROOT::kInvalidDescriptorId

private

Definition at line 83 of file RNTupleDescriptor.hxx.

fFieldName

std::string ROOT::RFieldDescriptor::fFieldName

private

The leaf name, not including parent fields.

Definition at line 89 of file RNTupleDescriptor.hxx.

fFieldVersion

std::uint32_t ROOT::RFieldDescriptor::fFieldVersion = 0

private

The version of the C++-type-to-column translation mechanics.

Definition at line 85 of file RNTupleDescriptor.hxx.

fLinkIds

std::vector<ROOT::DescriptorId_t> ROOT::RFieldDescriptor::fLinkIds

private

The pointers in the other direction from parent to children.

They are serialized, too, to keep the order of sub fields.

Definition at line 106 of file RNTupleDescriptor.hxx.

fLogicalColumnIds

std::vector<ROOT::DescriptorId_t> ROOT::RFieldDescriptor::fLogicalColumnIds

private

The ordered list of columns attached to this field: first by representation index then by column index.

Definition at line 112 of file RNTupleDescriptor.hxx.

fNRepetitions

std::uint64_t ROOT::RFieldDescriptor::fNRepetitions = 0

private

The number of elements per entry for fixed-size arrays.

Definition at line 97 of file RNTupleDescriptor.hxx.

fParentId

ROOT::DescriptorId_t ROOT::RFieldDescriptor::fParentId = ROOT::kInvalidDescriptorId

private

Establishes sub field relationships, such as classes and collections.

Definition at line 101 of file RNTupleDescriptor.hxx.

fProjectionSourceId

ROOT::DescriptorId_t ROOT::RFieldDescriptor::fProjectionSourceId = ROOT::kInvalidDescriptorId

private

For projected fields, the source field ID.

Definition at line 103 of file RNTupleDescriptor.hxx.

fStructure

ROOT::ENTupleStructure ROOT::RFieldDescriptor::fStructure = ROOT::ENTupleStructure::kInvalid

private

The structural information carried by this field in the data model tree.

Definition at line 99 of file RNTupleDescriptor.hxx.

fTypeAlias

std::string ROOT::RFieldDescriptor::fTypeAlias

private

A typedef or using directive that resolved to the type name during field creation.

Definition at line 95 of file RNTupleDescriptor.hxx.

fTypeChecksum

std::optional<std::uint32_t> ROOT::RFieldDescriptor::fTypeChecksum

private

For custom classes, we store the ROOT TClass reported checksum to facilitate the use of I/O rules that identify types by their checksum.

Definition at line 115 of file RNTupleDescriptor.hxx.

fTypeName

std::string ROOT::RFieldDescriptor::fTypeName

private

The C++ type that was used when writing the field.

Definition at line 93 of file RNTupleDescriptor.hxx.

fTypeVersion

std::uint32_t ROOT::RFieldDescriptor::fTypeVersion = 0

private

The version of the C++ type itself.

Definition at line 87 of file RNTupleDescriptor.hxx.

Libraries for ROOT::RFieldDescriptor:

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

• tree/ntuple/v7/inc/ROOT/RNTupleDescriptor.hxx
• tree/ntuple/v7/src/RNTupleDescriptor.cxx