Abstract base class for a Nexus data set. More...

#include <NexusClasses.h>

Inheritance diagram for Mantid::NeXus::NXDataSet:

Public Member Functions
int	dim0 () const
	Returns the number of elements along the first dimension. More...

int	dim1 () const
	Returns the number of elements along the second dimension. More...

int	dim2 () const
	Returns the number of elements along the third dimension. More...

int	dim3 () const
	Returns the number of elements along the fourth dimension. More...

int	dims (int i) const
	Returns the number of elements along i-th dimension. More...

virtual void	load (const int blocksize=1, int i=-1, int j=-1, int k=-1, int l=-1)
	Load the data from the file. More...

std::string	name () const
	Returns the name of the data set. More...

std::string	NX_class () const override
	NX class name. Returns "SDS". More...

	NXDataSet (const NXClass &parent, const std::string &name)
	Constructor. More...

void	open ()
	Opens the data set. More...

void	openLocal ()
	Opens datasets faster but the parent group must be already open. More...

int	rank () const
	Returns the rank (number of dimensions) of the data. The maximum is 4. More...

int	type () const
	Returns the Nexus type of the data. The types are defied in napi.h. More...

Public Member Functions inherited from Mantid::NeXus::NXObject
std::string	name () const
	Returns the name of the object. More...

virtual std::string	NX_class () const =0
	Return the NX class name for a class (HDF group) or "SDS" for a data set;. More...

	NXObject (const NXhandle fileID, const NXClass *parent, const std::string &name)
	NXObject constructor. More...

std::string	path () const
	Returns the absolute path to the object. More...

virtual	~NXObject ()=default

Protected Member Functions
void	getData (void *data)
	Wrapper to the NXgetdata. More...

void	getSlab (void *data, int start[], int size[])
	Wrapper to the NXgetslab. More...

Private Attributes
NXInfo	m_info
	Holds the data info. More...

Additional Inherited Members
Public Attributes inherited from Mantid::NeXus::NXObject
NXAttributes	attributes
	Attributes. More...

NXhandle	m_fileID
	Nexus file id. More...

Protected Attributes inherited from Mantid::NeXus::NXObject
bool	m_open
	Set to true if the object has been open. More...

std::string	m_path
	Keeps the absolute path to the object. More...

Detailed Description

Abstract base class for a Nexus data set.

A typical use include:

Creating a dataset object using either the concrete type constructor or specialized methods of NXClass'es
Opening the dataset with open() method. Specialized NXClass creation methods call open() internally (so no need to call it again).
Loading the data using load(...) method. The data can be loaded either in full or by chunks of smaller rank (dimension)

There is no need to free the memory allocated by the NXDataSet as it is done at the destruction.

Definition at line 135 of file NexusClasses.h.

Constructor & Destructor Documentation

◆ NXDataSet()

Mantid::NeXus::NXDataSet::NXDataSet	(	const NXClass &	parent,
		const std::string &	name
	)

Constructor.

Parameters

parent	:: The parent Nexus class. In terms of HDF it is the group containing the dataset.
name	:: The name of the dataset relative to its parent

Definition at line 431 of file NexusClasses.cpp.

References m_info, name(), and Mantid::NeXus::NXInfo::nxname.

Member Function Documentation

◆ dim0()

int Mantid::NeXus::NXDataSet::dim0 ( ) const

Returns the number of elements along the first dimension.

The size of the first dimension of data.

Returns: An integer indicating the size of the dimension.

Exceptions

out_of_range error if requested on an object of rank 0

Definition at line 479 of file NexusClasses.cpp.

References Mantid::NeXus::NXInfo::dims, m_info, and Mantid::NeXus::NXInfo::rank.

◆ dim1()

int Mantid::NeXus::NXDataSet::dim1 ( ) const

Returns the number of elements along the second dimension.

The size of the second dimension of data.

Returns: An integer indicating the size of the dimension

Exceptions

out_of_range error if requested on an object of rank < 2

Definition at line 491 of file NexusClasses.cpp.

References Mantid::NeXus::NXInfo::dims, m_info, and Mantid::NeXus::NXInfo::rank.

◆ dim2()

int Mantid::NeXus::NXDataSet::dim2 ( ) const

Returns the number of elements along the third dimension.

The size of the third dimension of data.

Returns: An integer indicating the size of the dimension

Exceptions

out_of_range error if requested on an object of rank < 3

Definition at line 503 of file NexusClasses.cpp.

References Mantid::NeXus::NXInfo::dims, m_info, and Mantid::NeXus::NXInfo::rank.

◆ dim3()

int Mantid::NeXus::NXDataSet::dim3 ( ) const

Returns the number of elements along the fourth dimension.

The size of the fourth dimension of data.

Returns: An integer indicating the size of the dimension

Exceptions

out_of_range error if requested on an object of rank < 4

Definition at line 515 of file NexusClasses.cpp.

References Mantid::NeXus::NXInfo::dims, m_info, and Mantid::NeXus::NXInfo::rank.

Referenced by Mantid::NeXus::NXDataSetTyped< T >::load().

◆ dims()

int Mantid::NeXus::NXDataSet::dims ( int i ) const

inline

Returns the number of elements along i-th dimension.

Definition at line 149 of file NexusClasses.h.

◆ getData()

void Mantid::NeXus::NXDataSet::getData ( void * data )

protected

Wrapper to the NXgetdata.

Parameters

data	:: The pointer to the buffer accepting the data from the file.

Exceptions

runtime_error if the operation fails.

Definition at line 526 of file NexusClasses.cpp.

References Mantid::NeXus::NXObject::m_fileID, and name().

Referenced by Mantid::NeXus::NXDataSetTyped< T >::load().

◆ getSlab()

void Mantid::NeXus::NXDataSet::getSlab	(	void *	data,
		int	start[],
		int	size[]
	)

protected

Wrapper to the NXgetslab.

Parameters

data	:: The pointer to the buffer accepting the data from the file.
start	:: The array of starting indeces to read in from the file. The size of the array must be equal to the rank of the data.
size	:: The array of numbers of data elements to read along each dimenstion. The number of dimensions (the size of the array) must be equal to the rank of the data.

Exceptions

runtime_error if the operation fails.

Definition at line 544 of file NexusClasses.cpp.

References Mantid::NeXus::NXObject::m_fileID, and name().

Referenced by Mantid::NeXus::NXDataSetTyped< T >::load().

◆ load()

virtual void Mantid::NeXus::NXDataSet::load	(	const int	blocksize = `1`,
		int	i = `-1`,
		int	j = `-1`,
		int	k = `-1`,
		int	l = `-1`
	)

inlinevirtual

Load the data from the file.

Calling this method with all default arguments makes it to read in all the data.

Parameters

blocksize	:: The size of the block of data that should be read. Note that this is only used for rank 2 and 3 datasets currently
i	:: Calling load with non-negative i reads in a chunk of dimension rank()-1 and i is the index of the chunk. The rank of the data must be >= 1
j	:: Non-negative value makes it read a chunk of dimension rank()-2. i and j are its indices. The rank of the data must be >= 2
k	:: Non-negative value makes it read a chunk of dimension rank()-3. i,j and k are its indices. The rank of the data must be >= 3
l	:: Non-negative value makes it read a chunk of dimension rank()-4. i,j,k and l are its indices. The rank of the data must be 4

Reimplemented in Mantid::NeXus::NXDataSetTyped< T >.

Definition at line 180 of file NexusClasses.h.

◆ name()

std::string Mantid::NeXus::NXDataSet::name ( ) const

inline

Returns the name of the data set.

Definition at line 159 of file NexusClasses.h.

Referenced by getData(), getSlab(), NXDataSet(), open(), and openLocal().

◆ NX_class()

std::string Mantid::NeXus::NXDataSet::NX_class ( ) const

inlineoverridevirtual

NX class name. Returns "SDS".

Implements Mantid::NeXus::NXObject.

Definition at line 140 of file NexusClasses.h.

◆ open()

void Mantid::NeXus::NXDataSet::open ( )

Opens the data set.

Does not read in any data. Call load(...) to load the data

Definition at line 443 of file NexusClasses.cpp.

References Mantid::NeXus::NXInfo::dims, Mantid::NeXus::NXObject::getAttributes(), Mantid::NeXus::NXObject::m_fileID, m_info, Mantid::NeXus::NXObject::m_path, name(), Mantid::NeXus::NXInfo::rank, and Mantid::NeXus::NXInfo::type.

Referenced by Mantid::DataHandling::LoadISISNexus2::loadPeriodData(), Mantid::NeXus::NXData::openData(), and Mantid::NeXus::NXClass::openNXDataSet().

◆ openLocal()

void Mantid::NeXus::NXDataSet::openLocal ( )

Opens datasets faster but the parent group must be already open.

Definition at line 463 of file NexusClasses.cpp.

References Mantid::NeXus::NXInfo::dims, Mantid::NeXus::NXObject::getAttributes(), Mantid::NeXus::NXObject::m_fileID, m_info, name(), Mantid::NeXus::NXInfo::rank, and Mantid::NeXus::NXInfo::type.

Referenced by Mantid::NeXus::NXLog::createTimeSeries(), and Mantid::DataHandling::LoadNexusProcessed::doAccelleratedMultiPeriodLoading().

◆ rank()

int Mantid::NeXus::NXDataSet::rank ( ) const

inline

Returns the rank (number of dimensions) of the data. The maximum is 4.

Definition at line 147 of file NexusClasses.h.

Referenced by Mantid::NeXus::NXDataSetTyped< T >::load(), Mantid::DataHandling::LoadMuonNexus2::loadData(), Mantid::DataHandling::LoadNexusProcessed::loadEntry(), and Mantid::DataHandling::LoadNexusProcessed::loadEventEntry().

◆ type()

int Mantid::NeXus::NXDataSet::type ( ) const

inline

Returns the Nexus type of the data. The types are defied in napi.h.

Definition at line 161 of file NexusClasses.h.

Member Data Documentation

◆ m_info

NXInfo Mantid::NeXus::NXDataSet::m_info

private

Holds the data info.

Definition at line 194 of file NexusClasses.h.

Referenced by dim0(), dim1(), dim2(), dim3(), NXDataSet(), open(), and openLocal().

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

Framework/Nexus/inc/MantidNexus/NexusClasses.h
Framework/Nexus/src/NexusClasses.cpp

Public Member Functions

Protected Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ NXDataSet()

Member Function Documentation

◆ dim0()

◆ dim1()

◆ dim2()

◆ dim3()

◆ dims()

◆ getData()

◆ getSlab()

◆ load()

◆ name()

◆ NX_class()

◆ open()

◆ openLocal()

◆ rank()

◆ type()

Member Data Documentation

◆ m_info