The BinaryFile template is a helper function for loading simple binary files. More...

#include <BinaryFile.h>

Public Member Functions
	BinaryFile ()
	Empty constructor.

	BinaryFile (std::filesystem::path const &filepath)
	Constructor - open a file.

void	close ()
	Close the file.

size_t	getBufferSize (const size_t num_items) const
	Get a buffer size for loading blocks of data.

size_t	getNumElements () const
	Returns the # of elements in the file (cached result of getFileSize)

size_t	getOffset () const
	Returns the current offset into the file.

std::vector< T >	loadAll ()
	Loads the entire contents of the file into a pointer to a std::vector.

std::vector< T >	loadAllIntoVector ()
	Loads the entire contents of the file into a std::vector.

size_t	loadBlock (T *buffer, size_t block_size)
	Loads a single block from file and returns a pointer to a vector containing it.

size_t	loadBlockAt (T *buffer, size_t newOffset, size_t block_size)
	Loads a single block from file and returns a pointer to a vector containing it.

void	open (std::filesystem::path const &filepath)
	Open a file and keep a handle to the file.

	~BinaryFile ()
	Destructor, close the file if needed.

Private Member Functions
size_t	getFileSize ()
	Get the size of a file as a multiple of a particular data type.

Private Attributes
std::unique_ptr< std::ifstream >	handle
	File stream.

size_t	num_elements
	Number of elements of size T in the file.

size_t	obj_size
	Size of each object.

size_t	offset
	Offset into the file, if loading in blocks.

Detailed Description

template<typename T>
class Mantid::Kernel::BinaryFile< T >

The BinaryFile template is a helper function for loading simple binary files.

The file format must be a simple sequence of objects of type T.
To load, first create an object of type BinaryFile<T>
The file provided when opening is checked so that its size is an even multiple of sizeof(T); an error is thrown otherwise.

NOTE: Data saving and loading is little-endian (on Win, Linux, and Intel Mac). Converting from a byte buffer loaded from disk to the T type is done with a reinterpret_cast<T>.

Definition at line 43 of file BinaryFile.h.

Constructor & Destructor Documentation

◆ BinaryFile() [1/2]

template<typename T >

Mantid::Kernel::BinaryFile< T >::BinaryFile ( )

inline

Empty constructor.

Definition at line 47 of file BinaryFile.h.

◆ BinaryFile() [2/2]

template<typename T >

Mantid::Kernel::BinaryFile< T >::BinaryFile ( std::filesystem::path const & filepath )

inline

Constructor - open a file.

Definition at line 51 of file BinaryFile.h.

◆ ~BinaryFile()

template<typename T >

Mantid::Kernel::BinaryFile< T >::~BinaryFile ( )

inline

Destructor, close the file if needed.

Definition at line 54 of file BinaryFile.h.

Member Function Documentation

◆ close()

template<typename T >

void Mantid::Kernel::BinaryFile< T >::close ( )

inline

Close the file.

Definition at line 79 of file BinaryFile.h.

◆ getBufferSize()

template<typename T >

size_t Mantid::Kernel::BinaryFile< T >::getBufferSize ( const size_t num_items ) const

inline

Get a buffer size for loading blocks of data.

Parameters

num_items

Returns: the buffer size

Definition at line 93 of file BinaryFile.h.

References Mantid::Kernel::DEFAULT_BLOCK_SIZE.

◆ getFileSize()

template<typename T >

size_t Mantid::Kernel::BinaryFile< T >::getFileSize ( )

inlineprivate

Get the size of a file as a multiple of a particular data type.

Returns: the size of the file normalized to the data type

Exceptions

runtime_error	if the file size is not compatible
runtime_error	if the handle is not open.

Definition at line 228 of file BinaryFile.h.

◆ getNumElements()

template<typename T >

size_t Mantid::Kernel::BinaryFile< T >::getNumElements ( ) const

inline

Returns the # of elements in the file (cached result of getFileSize)

Definition at line 83 of file BinaryFile.h.

Referenced by Mantid::DataHandling::DetermineChunking::exec(), Mantid::DataHandling::LoadEventPreNexus2::loadPixelMap(), and Mantid::DataHandling::LoadEventPreNexus2::readPulseidFile().

◆ getOffset()

template<typename T >

size_t Mantid::Kernel::BinaryFile< T >::getOffset ( ) const

inline

Returns the current offset into the file.

Definition at line 86 of file BinaryFile.h.

◆ loadAll()

template<typename T >

std::vector< T > Mantid::Kernel::BinaryFile< T >::loadAll ( )

inline

Loads the entire contents of the file into a pointer to a std::vector.

The file is closed once done.

Returns: file contents in a vector

Definition at line 106 of file BinaryFile.h.

Referenced by Mantid::DataHandling::LoadEventPreNexus2::readPulseidFile().

◆ loadAllIntoVector()

template<typename T >

std::vector< T > Mantid::Kernel::BinaryFile< T >::loadAllIntoVector ( )

inline

Loads the entire contents of the file into a std::vector.

The file is closed once done.

Returns: :: vector with contents of the file

Definition at line 142 of file BinaryFile.h.

Referenced by Mantid::DataHandling::LoadPreNexusMonitors::exec(), and Mantid::DataHandling::LoadEventPreNexus2::loadPixelMap().

◆ loadBlock()

template<typename T >

size_t Mantid::Kernel::BinaryFile< T >::loadBlock	(	T *	buffer,
		size_t	block_size
	)

inline

Loads a single block from file and returns a pointer to a vector containing it.

This can be called repeatedly to load an entire file.

Parameters

block_size	how many elements to load in the block. If there are not enough elements, the vector returned is smaller than block_size
buffer	array of block_size[] of T; must have been allocated before.

Returns: loaded_size, actually how many elements were loaded.

Definition at line 183 of file BinaryFile.h.

◆ loadBlockAt()

template<typename T >

size_t Mantid::Kernel::BinaryFile< T >::loadBlockAt	(	T *	buffer,
		size_t	newOffset,
		size_t	block_size
	)

inline

Loads a single block from file and returns a pointer to a vector containing it.

This can be called repeatedly to load an entire file.

Parameters

buffer	array of block_size[] of T; must have been allocated before.
newOffset	offset (in # of elements) of where to start loading in the file.
block_size	how many elements to load in the block. If there are not enough elements, the vector returned is smaller than block_size

Returns: loaded_size, actually how many elements were loaded.

Definition at line 212 of file BinaryFile.h.

◆ open()

template<typename T >

void Mantid::Kernel::BinaryFile< T >::open ( std::filesystem::path const & filepath )

inline

Open a file and keep a handle to the file.

Parameters

filepath :: full path to open

Exceptions

runtime_error	if the file size is not an even multiple of the type size
invalid_argument	if the file does not exist

Definition at line 63 of file BinaryFile.h.

Member Data Documentation

◆ handle

template<typename T >

std::unique_ptr<std::ifstream> Mantid::Kernel::BinaryFile< T >::handle

private

File stream.

Definition at line 256 of file BinaryFile.h.

◆ num_elements

template<typename T >

size_t Mantid::Kernel::BinaryFile< T >::num_elements

private

Number of elements of size T in the file.

Definition at line 260 of file BinaryFile.h.

◆ obj_size

template<typename T >

size_t Mantid::Kernel::BinaryFile< T >::obj_size

private

Size of each object.

Definition at line 258 of file BinaryFile.h.

◆ offset

template<typename T >

size_t Mantid::Kernel::BinaryFile< T >::offset

private

Offset into the file, if loading in blocks.

Definition at line 262 of file BinaryFile.h.

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

Framework/Kernel/inc/MantidKernel/BinaryFile.h

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ BinaryFile() [1/2]

◆ BinaryFile() [2/2]

◆ ~BinaryFile()

Member Function Documentation

◆ close()

◆ getBufferSize()

◆ getFileSize()

◆ getNumElements()

◆ getOffset()

◆ loadAll()

◆ loadAllIntoVector()

◆ loadBlock()

◆ loadBlockAt()

◆ open()

Member Data Documentation

◆ handle

◆ num_elements

◆ obj_size

◆ offset