HDF5 C++ API Reference Manual

 

 

H5::DataSet Class Reference

#include <H5DataSet.h>

Inheritance diagram for H5::DataSet:

List of all members.

Public Member Functions
virtual void	close ()
	Closes this dataset.
void	extend (const hsize_t *size) const
	Extends a dataset with unlimited dimension.
void	fillMemBuf (const void *fill, DataType &fill_type, void *buf, DataType &buf_type, DataSpace &space)
	Fills a selection in memory with a value.
void	fillMemBuf (void *buf, DataType &buf_type, DataSpace &space)
	This is an overloaded member function, provided for convenience. It differs from the above function in that it only takes the the last three arguments.
DSetCreatPropList	getCreatePlist () const
	Gets the dataset creation property list.
haddr_t	getOffset () const
	Returns the address of this dataset in the file.
virtual DataSpace	getSpace () const
	Gets a copy of the dataspace of this dataset.
void	getSpaceStatus (H5D_space_status_t &status) const
	Determines whether space has been allocated for a dataset.
virtual hsize_t	getStorageSize () const
	Returns the amount of storage required for a dataset.
virtual size_t	getInMemDataSize () const
	Gets the size in memory of the dataset's data.
hsize_t	getVlenBufSize (DataType &type, DataSpace &space) const
	Returns the number of bytes required to store VL data.
void	read (void *buf, const DataType &mem_type, const DataSpace &mem_space=DataSpace::ALL, const DataSpace &file_space=DataSpace::ALL, const DSetMemXferPropList &xfer_plist=DSetMemXferPropList::DEFAULT) const
	Reads raw data from the specified dataset.
void	read (H5std_string &buf, const DataType &mem_type, const DataSpace &mem_space=DataSpace::ALL, const DataSpace &file_space=DataSpace::ALL, const DSetMemXferPropList &xfer_plist=DSetMemXferPropList::DEFAULT) const
	This is an overloaded member function, provided for convenience. It takes a reference to a H5std_string for the buffer.
void	write (const void *buf, const DataType &mem_type, const DataSpace &mem_space=DataSpace::ALL, const DataSpace &file_space=DataSpace::ALL, const DSetMemXferPropList &xfer_plist=DSetMemXferPropList::DEFAULT) const
	Writes raw data from an application buffer to a dataset.
void	write (const H5std_string &buf, const DataType &mem_type, const DataSpace &mem_space=DataSpace::ALL, const DataSpace &file_space=DataSpace::ALL, const DSetMemXferPropList &xfer_plist=DSetMemXferPropList::DEFAULT) const
	This is an overloaded member function, provided for convenience. It takes a reference to a H5std_string for the buffer.
int	iterateElems (void *buf, const DataType &type, const DataSpace &space, H5D_operator_t op, void *op_data=NULL)
	Iterates over all selected elements in a dataspace.
H5G_obj_t	getObjType (void *ref, H5R_type_t ref_type=H5R_OBJECT) const
	Retrieves the type of object that an object reference points to.
DataSpace	getRegion (void *ref, H5R_type_t ref_type=H5R_DATASET_REGION) const
	Retrieves a dataspace with the region pointed to selected.
virtual H5std_string	fromClass () const
	Returns this class name.
	DataSet (H5Object &obj, const void *ref, H5R_type_t ref_type=H5R_OBJECT)
	Given a reference, ref, to an hdf5 dataset, creates a DataSet object.
	DataSet (H5File &h5file, const void *ref, H5R_type_t ref_type=H5R_OBJECT)
	Given a reference, ref, to an hdf5 dataset, creates a DataSet object.
	DataSet (Attribute &attr, const void *ref, H5R_type_t ref_type=H5R_OBJECT)
	Given a reference, ref, to an hdf5 dataset, creates a DataSet object.
	DataSet ()
	Default constructor: creates a stub DataSet.
	DataSet (const DataSet &original)
	Copy constructor: makes a copy of the original DataSet object.
	DataSet (const hid_t existing_id)
	Creates an DataSet object using the id of an existing dataset.
virtual hid_t	getId () const
	Get the id of this dataset.
virtual	~DataSet ()
	Properly terminates access to this dataset.
Static Public Member Functions
static void	vlenReclaim (const DataType &type, const DataSpace &space, const DSetMemXferPropList &xfer_plist, void *buf)
	Reclaims VL datatype memory buffers.
static void	vlenReclaim (void *buf, const DataType &type, const DataSpace &space=DataSpace::ALL, const DSetMemXferPropList &xfer_plist=DSetMemXferPropList::DEFAULT)
	Reclaims VL datatype memory buffers.

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Detailed Description

Examples:

chunks.cpp, compound.cpp, create.cpp, extend_ds.cpp, h5group.cpp, readdata.cpp, and writedata.cpp.

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Constructor & Destructor Documentation

H5::DataSet::DataSet	(	H5Object &	obj,
		const void *	ref,
		H5R_type_t	ref_type = H5R_OBJECT
	)

Given a reference, ref, to an hdf5 dataset, creates a DataSet object.

Parameters:

	obj	- IN: Dataset reference object is in or location of object that the dataset is located within.
	ref	- IN: Reference pointer
	ref_type	- IN: Reference type - default to H5R_OBJECT

Exceptions:

H5::DataSetIException

Description

obj can be DataSet, Group, H5File, or named DataType, that is a datatype that has been named by DataType::commit.

H5::DataSet::DataSet	(	H5File &	h5file,
		const void *	ref,
		H5R_type_t	ref_type = H5R_OBJECT
	)

Given a reference, ref, to an hdf5 dataset, creates a DataSet object.

Parameters:

	h5file	- IN: Location referenced object is in
	ref	- IN: Reference pointer
	ref_type	- IN: Reference type - default to H5R_OBJECT

Exceptions:

H5::DataSetIException

H5::DataSet::DataSet	(	Attribute &	attr,
		const void *	ref,
		H5R_type_t	ref_type = H5R_OBJECT
	)

Given a reference, ref, to an hdf5 dataset, creates a DataSet object.

Parameters:

	attr	- IN: Specifying location where the referenced object is in
	ref	- IN: Reference pointer
	ref_type	- IN: Reference type - default to H5R_OBJECT

Exceptions:

H5::ReferenceException

H5::DataSet::DataSet

(

)

Default constructor: creates a stub DataSet.

H5::DataSet::DataSet

(

const DataSet &

original

)

Copy constructor: makes a copy of the original DataSet object.

Parameters:

original

- IN: DataSet instance to copy

H5::DataSet::DataSet

(

const hid_t

existing_id

)

Creates an DataSet object using the id of an existing dataset.

Parameters:

existing_id

- IN: Id of an existing dataset

H5::DataSet::~DataSet

(

)

[virtual]

Properly terminates access to this dataset.

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Member Function Documentation

void H5::DataSet::close

(

)

[virtual]

Closes this dataset.

Exceptions:

H5::DataSetIException

void H5::DataSet::extend

(

const hsize_t *

size

)

const

Extends a dataset with unlimited dimension.

Parameters:

size

- IN: Array containing the new magnitude of each dimension

Exceptions:

H5::DataSetIException

Description

For more information, please see the Description section in C layer Reference Manual at:

http://www.hdfgroup.org/HDF5/doc/RM/RM_H5D.html#Dataset-Extend

Examples:

extend_ds.cpp.

void H5::DataSet::fillMemBuf	(	const void *	fill,
		DataType &	fill_type,
		void *	buf,
		DataType &	buf_type,
		DataSpace &	space
	)

Fills a selection in memory with a value.

Parameters:

	fill	- IN: Pointer to fill value to use - default NULL
	fill_type	- IN: Datatype of the fill value
	buf	- IN/OUT: Memory buffer to fill selection within
	buf_type	- IN: Datatype of the elements in buffer
	space	- IN: Dataspace describing memory buffer & containing selection to use

Exceptions:

H5::DataSetIException

void H5::DataSet::fillMemBuf	(	void *	buf,
		DataType &	buf_type,
		DataSpace &	space
	)

This is an overloaded member function, provided for convenience. It differs from the above function in that it only takes the the last three arguments.

Parameters:

	buf	- IN/OUT: Memory buffer to fill selection within
	buf_type	- IN: Datatype of the elements in buffer
	space	- IN: Dataspace describing memory buffer & containing selection to use

Exceptions:

H5::DataSetIException

DSetCreatPropList H5::DataSet::getCreatePlist

(

)

const

Gets the dataset creation property list.

Returns:

DSetCreatPropList instance

Exceptions:

H5::DataSetIException

Examples:

chunks.cpp.

haddr_t H5::DataSet::getOffset

(

)

const

Returns the address of this dataset in the file.

Returns:

Address of dataset

Exceptions:

H5::DataSetIException

DataSpace H5::DataSet::getSpace

(

)

const [virtual]

Gets a copy of the dataspace of this dataset.

Returns:

DataSpace instance

Exceptions:

H5::DataSetIException

Implements H5::AbstractDs.

Examples:

chunks.cpp, extend_ds.cpp, readdata.cpp, and writedata.cpp.

void H5::DataSet::getSpaceStatus

(

H5D_space_status_t &

status

)

const

Determines whether space has been allocated for a dataset.

Parameters:

status

- OUT: Space allocation status

Exceptions:

H5::DataSetIException

hsize_t H5::DataSet::getStorageSize

(

)

const [virtual]

Returns the amount of storage required for a dataset.

Returns:

Size of the storage or 0, for no data

Exceptions:

H5::DataSetIException

Implements H5::AbstractDs.

size_t H5::DataSet::getInMemDataSize

(

)

const [virtual]

Gets the size in memory of the dataset's data.

Returns:

Size of data (in memory)

Exceptions:

H5::DataSetIException

Implements H5::AbstractDs.

hsize_t H5::DataSet::getVlenBufSize	(	DataType &	type,
		DataSpace &	space
	)			const

Returns the number of bytes required to store VL data.

Returns:

Amount of storage

Exceptions:

H5::DataSetIException

void H5::DataSet::vlenReclaim	(	const DataType &	type,
		const DataSpace &	space,
		const DSetMemXferPropList &	xfer_plist,
		void *	buf
	)			[static]

Reclaims VL datatype memory buffers.

Parameters:

	type	- IN: Datatype, which is the datatype stored in the buffer
	space	- IN: Selection for the memory buffer to free the VL datatypes within
	xfer_plist	- IN: Property list used to create the buffer
	buf	- IN: Pointer to the buffer to be reclaimed

Exceptions:

H5::DataSetIException

void H5::DataSet::vlenReclaim	(	void *	buf,
		const DataType &	type,
		const DataSpace &	space = DataSpace::ALL,
		const DSetMemXferPropList &	xfer_plist = DSetMemXferPropList::DEFAULT
	)			[static]

Reclaims VL datatype memory buffers.

Parameters:

	type	- IN: Datatype, which is the datatype stored in the buffer
	space	- IN: Selection for the memory buffer to free the VL datatypes within
	xfer_plist	- IN: Property list used to create the buffer
	buf	- IN: Pointer to the buffer to be reclaimed

Exceptions:

H5::DataSetIException

void H5::DataSet::read	(	void *	buf,
		const DataType &	mem_type,
		const DataSpace &	mem_space = DataSpace::ALL,
		const DataSpace &	file_space = DataSpace::ALL,
		const DSetMemXferPropList &	xfer_plist = DSetMemXferPropList::DEFAULT
	)			const

Reads raw data from the specified dataset.

Parameters:

	buf	- IN: Buffer for read data
	mem_type	- IN: Memory datatype
	mem_space	- IN: Memory dataspace
	file_space	- IN: Dataset's dataspace in the file
	xfer_plist	- IN: Transfer property list for this I/O operation

Exceptions:

H5::DataSetIException

Description

This function reads raw data from this dataset into the buffer buf, converting from file datatype and dataspace to memory datatype mem_type and dataspace mem_space.

Examples:

chunks.cpp, compound.cpp, extend_ds.cpp, readdata.cpp, and writedata.cpp.

void H5::DataSet::read	(	H5std_string &	strg,
		const DataType &	mem_type,
		const DataSpace &	mem_space = DataSpace::ALL,
		const DataSpace &	file_space = DataSpace::ALL,
		const DSetMemXferPropList &	xfer_plist = DSetMemXferPropList::DEFAULT
	)			const

This is an overloaded member function, provided for convenience. It takes a reference to a H5std_string for the buffer.

Parameters:

	buf	- IN: Buffer for read data
	mem_type	- IN: Memory datatype
	mem_space	- IN: Memory dataspace
	file_space	- IN: Dataset's dataspace in the file
	xfer_plist	- IN: Transfer property list for this I/O operation

Exceptions:

H5::DataSetIException

void H5::DataSet::write	(	const void *	buf,
		const DataType &	mem_type,
		const DataSpace &	mem_space = DataSpace::ALL,
		const DataSpace &	file_space = DataSpace::ALL,
		const DSetMemXferPropList &	xfer_plist = DSetMemXferPropList::DEFAULT
	)			const

Writes raw data from an application buffer to a dataset.

Parameters:

	buf	- IN: Buffer containing data to be written
	mem_type	- IN: Memory datatype
	mem_space	- IN: Memory dataspace
	file_space	- IN: Dataset's dataspace in the file
	xfer_plist	- IN: Transfer property list for this I/O operation

Exceptions:

H5::DataSetIException

Description

This function writes raw data from an application buffer buf to a dataset, converting from memory datatype mem_type and dataspace mem_space to file datatype and dataspace.

Examples:

compound.cpp, create.cpp, extend_ds.cpp, and writedata.cpp.

void H5::DataSet::write	(	const H5std_string &	buf,
		const DataType &	mem_type,
		const DataSpace &	mem_space = DataSpace::ALL,
		const DataSpace &	file_space = DataSpace::ALL,
		const DSetMemXferPropList &	xfer_plist = DSetMemXferPropList::DEFAULT
	)			const

This is an overloaded member function, provided for convenience. It takes a reference to a H5std_string for the buffer.

int H5::DataSet::iterateElems	(	void *	buf,
		const DataType &	type,
		const DataSpace &	space,
		H5D_operator_t	op,
		void *	op_data = NULL
	)

Iterates over all selected elements in a dataspace.

Parameters:

	buf	- IN/OUT: Pointer to the buffer in memory containing the elements to iterate over
	type	- IN: Datatype for the elements stored in buf
	space	- IN: Dataspace for buf. Also contains the selection to iterate over.
	op	- IN: Function pointer to the routine to be called for each element in buf iterated over
	op_data	- IN/OUT: Pointer to any user-defined data associated with the operation

Exceptions:

H5::DataSetIException

Note:

This function may not work correctly yet - it's still under development.

H5G_obj_t H5::DataSet::getObjType	(	void *	ref,
		H5R_type_t	ref_type = H5R_OBJECT
	)			const

Retrieves the type of object that an object reference points to.

Parameters:

	ref_type	- IN: Type of reference to query, valid values are: H5R_OBJECT - Reference is an object reference. H5R_DATASET_REGION - Reference is a dataset region reference.
	ref	- IN: Reference to query

Returns:

An object type, which can be one of the following:

• H5G_LINK (0) - Object is a symbolic link.
• H5G_GROUP (1) - Object is a group.
• H5G_DATASET (2) - Object is a dataset.
• H5G_TYPE (3) - Object is a named datatype

Exceptions:

H5::DataSetIException

DataSpace H5::DataSet::getRegion	(	void *	ref,
		H5R_type_t	ref_type = H5R_DATASET_REGION
	)			const

Retrieves a dataspace with the region pointed to selected.

Parameters:

	ref	- IN: Reference to get region of
	ref_type	- IN: Type of reference to get region of - default to H5R_DATASET_REGION

Returns:

DataSpace instance

Exceptions:

H5::DataSetIException

virtual H5std_string H5::DataSet::fromClass

(

)

const [inline, virtual]

Returns this class name.

Implements H5::AbstractDs.

hid_t H5::DataSet::getId

(

)

const [virtual]

Get the id of this dataset.

Implements H5::IdComponent.

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