HDF5 C++ API Reference Manual

 

 

 

H5::DSetCreatPropList Class Reference

#include <H5DcreatProp.h>

Inheritance diagram for H5::DSetCreatPropList:

List of all members.

Public Member Functions
	DSetCreatPropList ()
	Default constructor: creates a stub dataset creation property list.
bool	allFiltersAvail () const
	Queries whether all the filters set in this property list are available currently.
H5D_alloc_time_t	getAllocTime () const
	Get space allocation time for this property.
void	setAllocTime (H5D_alloc_time_t alloc_time) const
	Sets space allocation time for dataset during creation.
int	getChunk (int max_ndims, hsize_t *dim) const
	Retrieves the size of the chunks used to store a chunked layout dataset.
void	setChunk (int ndims, const hsize_t *dim) const
	Sets the size of the chunks used to store a chunked layout dataset.
void	getExternal (unsigned idx, size_t name_size, char *name, off_t &offset, hsize_t &size) const
	Returns information about an external file.
int	getExternalCount () const
	Returns the number of external files for a dataset.
H5D_fill_time_t	getFillTime () const
	Gets fill value writing time.
void	setFillTime (H5D_fill_time_t fill_time) const
	Sets fill value writing time for dataset.
void	getFillValue (const DataType &fvalue_type, void *value) const
	Retrieves a dataset fill value.
void	setFillValue (const DataType &fvalue_type, const void *value) const
	Sets a dataset fill value.
H5Z_filter_t	getFilter (int filter_number, unsigned int &flags, size_t &cd_nelmts, unsigned int *cd_values, size_t namelen, char name[]) const
	Returns information about a filter in a pipeline.
void	getFilterById (H5Z_filter_t filter_id, unsigned int &flags, size_t &cd_nelmts, unsigned int *cd_values, size_t namelen, char name[]) const
	Returns information about a filter in a pipeline given the filter id.
H5D_layout_t	getLayout () const
	Retrieves the layout type of this property list.
void	setLayout (H5D_layout_t layout) const
	Sets the type of storage used store the raw data for a dataset.
int	getNfilters () const
	Returns the number of filters in the pipeline.
H5D_fill_value_t	isFillValueDefined () const
	Check if fill value has been defined for this property.
void	modifyFilter (H5Z_filter_t filter_id, unsigned int flags, size_t cd_nelmts, const unsigned int cd_values[]) const
	Modifies the specified filter.
void	removeFilter (H5Z_filter_t filter_id) const
	Removes one or more filters.
void	setDeflate (int level) const
	Sets compression method and compression level.
void	setExternal (const char *name, off_t offset, hsize_t size) const
	Adds an external file to the list of external files.
void	setFilter (H5Z_filter_t filter, unsigned int flags=0, size_t cd_nelmts=0, const unsigned int cd_values[]=NULL) const
	Adds a filter to the filter pipeline.
void	setFletcher32 () const
	Sets Fletcher32 checksum of EDC for this property list.
void	setShuffle () const
	Sets method of the shuffle filter.
void	setSzip (unsigned int options_mask, unsigned int pixels_per_block) const
	Sets up for the use of the SZIP compression filter.
virtual H5std_string	fromClass () const
	DSetCreatPropList (const DSetCreatPropList &orig)
	Copy constructor: makes a copy of the original DSetCreatPropList object.
	DSetCreatPropList (const hid_t plist_id)
	Creates a DSetCreatPropList object using the id of an existing dataset creation property list.
virtual	~DSetCreatPropList ()
	Noop destructor.
Static Public Attributes
static const DSetCreatPropList	DEFAULT
	Constant for dataset creation default property.

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Detailed Description

Examples:

chunks.cpp, extend_ds.cpp, and h5group.cpp.

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Constructor & Destructor Documentation

H5::DSetCreatPropList::DSetCreatPropList

(

)

Default constructor: creates a stub dataset creation property list.

H5::DSetCreatPropList::DSetCreatPropList

(

const DSetCreatPropList &

orig

)

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

H5::DSetCreatPropList::DSetCreatPropList

(

const hid_t

plist_id

)

Creates a DSetCreatPropList object using the id of an existing dataset creation property list.

H5::DSetCreatPropList::~DSetCreatPropList

(

)

[virtual]

Noop destructor.

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Member Function Documentation

bool H5::DSetCreatPropList::allFiltersAvail

(

)

const

Queries whether all the filters set in this property list are available currently.

Returns:

true if all filters available, and false if one or more filters not currently available

Exceptions:

H5::PropListIException

H5D_alloc_time_t H5::DSetCreatPropList::getAllocTime

(

)

const

Get space allocation time for this property.

Returns:

Space allocation time.

Exceptions:

H5::PropListIException

Description

The values of space allocation time can be one of the followings:

• H5D_ALLOC_TIME_DEFAULT
• H5D_ALLOC_TIME_EARLY
• H5D_ALLOC_TIME_LATE
• H5D_ALLOC_TIME_INCR

void H5::DSetCreatPropList::setAllocTime

(

H5D_alloc_time_t

alloc_time

)

const

Sets space allocation time for dataset during creation.

Parameters:

alloc_time

- IN: Allocation time

Exceptions:

H5::PropListIException

Description

Valid values for space allocation time include:

• H5D_ALLOC_TIME_DEFAULT
• H5D_ALLOC_TIME_EARLY
• H5D_ALLOC_TIME_LATE
• H5D_ALLOC_TIME_INCR

int H5::DSetCreatPropList::getChunk	(	int	max_ndims,
		hsize_t *	dim
	)			const

Retrieves the size of the chunks used to store a chunked layout dataset.

Parameters:

	max_ndims	- IN: Size of dim array
	dim	- OUT: Array to store the chunk dimensions

Exceptions:

H5::PropListIException

Examples:

chunks.cpp.

void H5::DSetCreatPropList::setChunk	(	int	ndims,
		const hsize_t *	dim
	)			const

Sets the size of the chunks used to store a chunked layout dataset.

Parameters:

	ndims	- IN: Number of dimensions of each chunk
	dim	- IN: Array containing the size of each chunk

Exceptions:

H5::PropListIException

Description

The ndims parameter currently must have the same value as the rank of the dataset. The values of the dim array define the size of the chunks to store the dataset's raw data. As a side-effect, the layout of the dataset will be changed to H5D_CHUNKED, if it is not so already.

Examples:

extend_ds.cpp, and h5group.cpp.

void H5::DSetCreatPropList::getExternal	(	unsigned	idx,
		size_t	name_size,
		char *	name,
		off_t &	offset,
		hsize_t &	size
	)			const

Returns information about an external file.

Parameters:

	idx	- IN: Index of the external file, ranges [0-(N-1)] and returned by getExternalCount()
	name_size	- IN: Maximum length of name
	name	- IN: Name of the external file
	offset	- IN: Location to return an offset value
	size	- OUT: Location to return the size of the external file data

Exceptions:

H5::PropListIException

Description

The parameter idx ranges [0..N-1] where N is returned by getExternalCount(). At most name_size characters are copied into the name array. If the external file name is longer than name_size with the null terminator, the return value is not null terminated (similar to strncpy()). If name_size is zero or name is a null pointer, the external file name will not be returned. If offset or size are null pointers then the corresponding information will not be returned.

int H5::DSetCreatPropList::getExternalCount

(

)

const

Returns the number of external files for a dataset.

Returns:

Number of external files

Exceptions:

H5::PropListIException

H5D_fill_time_t H5::DSetCreatPropList::getFillTime

(

)

const

Gets fill value writing time.

Returns:

Fill value writing time

Exceptions:

H5::PropListIException

Description

Valid values for fill value writing time include

• H5D_FILL_TIME_NEVER
• H5D_FILL_TIME_ALLOC.

void H5::DSetCreatPropList::setFillTime

(

H5D_fill_time_t

fill_time

)

const

Sets fill value writing time for dataset.

Returns:

Fill value writing time

Exceptions:

H5::PropListIException

Description

Valid values for fill value writing time include

• H5D_FILL_TIME_NEVER
• H5D_FILL_TIME_ALLOC.

void H5::DSetCreatPropList::getFillValue	(	const DataType &	fvalue_type,
		void *	value
	)			const

Retrieves a dataset fill value.

Parameters:

	fvalue_type	- IN: Data type for the value passed via value
	value	- OUT: Pointer to buffer to hold the retrieved fill value

Exceptions:

H5::PropListIException

Description

The fill value is returned through value pointer and the memory is allocated by the caller. The fill value will be converted from its current data type to the specified by fvalue_type.

void H5::DSetCreatPropList::setFillValue	(	const DataType &	fvalue_type,
		const void *	value
	)			const

Sets a dataset fill value.

Parameters:

	fvalue_type	- IN: Data type for the value passed via value
	value	- IN: Pointer to buffer containing the fill value

Exceptions:

H5::PropListIException

Description

The datatype may differ from that of the dataset, but it must be one that the HDF5 library is able to convert value to the dataset datatype when the dataset is created. The default fill value is 0 (zero,) which is interpreted according to the actual dataset datatype.

For information on setting fill value, please refer to the C layer Reference Manual at: ../RM_H5P.html::Property-SetFillValue

Examples:

extend_ds.cpp.

H5Z_filter_t H5::DSetCreatPropList::getFilter	(	int	filter_number,
		unsigned int &	flags,
		size_t &	cd_nelmts,
		unsigned int *	cd_values,
		size_t	namelen,
		char	name[]
	)			const

Returns information about a filter in a pipeline.

Parameters:

	filter_number	- IN: Filter to get, range [0..N-1], where N is returned by H5Pget_nfilters()
	flags	- OUT: General properties of the filter
	cd_nelmts	- IN/OUT: Number of elements in cd_values /Number of values defined by the filter
	cd_values	- OUT: Array to hold the data; allocated by the user
	namelen	- OUT: Length of name
	name	- OUT: Name of the filter

Returns:

Filter id

Exceptions:

H5::PropListIException

Description

Failure occurs when filter_number is out of range.

void H5::DSetCreatPropList::getFilterById	(	H5Z_filter_t	filter_id,
		unsigned int &	flags,
		size_t &	cd_nelmts,
		unsigned int *	cd_values,
		size_t	namelen,
		char	name[]
	)			const

Returns information about a filter in a pipeline given the filter id.

Parameters:

	filter_id	- IN: Filter to get
	flags	- OUT: General properties of the filter
	cd_nelmts	- IN/OUT: Number of elements in cd_values /Number of values defined by the filter
	cd_values	- OUT: Array to hold the data; allocated by the user
	namelen	- IN: Length of name
	name	- OUT: Name of the filter

Exceptions:

H5::PropListIException

H5D_layout_t H5::DSetCreatPropList::getLayout

(

)

const

Retrieves the layout type of this property list.

Returns:

Layout type, which can be:

• H5D_COMPACT - raw data is stored in the object header in the file.
• H5D_CONTIGUOUS - raw data is stored separately from the object header in one contiguous chunk in the file.
• H5D_CHUNKED - raw data is stored separately from the object header in chunks in separate locations in the file.

Exceptions:

H5::PropListIException

Description

Examples:

chunks.cpp.

void H5::DSetCreatPropList::setLayout

(

H5D_layout_t

layout

)

const

Sets the type of storage used store the raw data for a dataset.

Parameters:

layout

- IN: Type of storage layout for raw data

Exceptions:

H5::PropListIException

Description

For information on setting layout type, please refer to ../RM_H5P.html::Property-SetLayout

int H5::DSetCreatPropList::getNfilters

(

)

const

Returns the number of filters in the pipeline.

Returns:

Number of filters

Exceptions:

H5::PropListIException

H5D_fill_value_t H5::DSetCreatPropList::isFillValueDefined

(

)

const

Check if fill value has been defined for this property.

Returns:

• H5D_FILL_VALUE_UNDEFINED =0,
• H5D_FILL_VALUE_DEFAULT =1,
• H5D_FILL_VALUE_USER_DEFINED =2

Exceptions:

H5::PropListIException

void H5::DSetCreatPropList::modifyFilter	(	H5Z_filter_t	filter_id,
		unsigned int	flags,
		size_t	cd_nelmts,
		const unsigned int	cd_values[]
	)			const

Modifies the specified filter.

Parameters:

	filter_id	- IN: Filter to get
	flags	- OUT: General properties of the filter
	cd_nelmts	- IN: Number of elements in cd_values OUT: Number of values defined by the filter
	cd_values	- OUT: Array to hold the data; allocated by the user

Exceptions:

H5::PropListIException

Description

The flags argument is a bit vector of the field: H5Z_FLAG_OPTIONAL(0x0001)

If this bit is set then the filter is optional. If the filter fails during a DataSet::write() operation then the filter is just excluded from the pipeline for the chunk for which it failed; the filter will not participate in the pipeline during a DataSet::read() of the chunk. If this bit is clear and the filter fails then the entire I/O operation fails.

void H5::DSetCreatPropList::removeFilter

(

H5Z_filter_t

filter_id

)

const

Removes one or more filters.

Parameters:

filter_id

- IN: Filter to remove

Exceptions:

H5::PropListIException

Description

Deletes a filter from the dataset creation property list; deletes all filters if filter_id is H5Z_FILTER_NONE.

void H5::DSetCreatPropList::setDeflate

(

int

level

)

const

Sets compression method and compression level.

Parameters:

level

- IN: Compression level, should [0..9], inclusive

Exceptions:

H5::PropListIException

Description

The function sets the compression method for this property list to H5D_COMPRESS_DEFLATE and the compression level to level. Lower compression levels are faster but result in less compression.

Examples:

h5group.cpp.

void H5::DSetCreatPropList::setExternal	(	const char *	name,
		off_t	offset,
		hsize_t	size
	)			const

Adds an external file to the list of external files.

Parameters:

	name	- IN: Name of the external file
	offset	- IN: Location where the data starts in the file
	size	- IN: Number of bytes reserved in the file for the data

Exceptions:

H5::PropListIException

Description

If a dataset is splitted across multiple files then the files should be defined in order. The total size of the dataset is the sum of the size arguments for all the external files. If the total size is larger than the size of a dataset then the dataset can be extended (provided the data space also allows the extending).

void H5::DSetCreatPropList::setFilter	(	H5Z_filter_t	filter_id,
		unsigned int	flags = 0,
		size_t	cd_nelmts = 0,
		const unsigned int	cd_values[] = NULL
	)			const

Adds a filter to the filter pipeline.

Parameters:

	filter_id	- IN: Filter to add
	flags	- IN: Specifies general properties of the filter
	cd_nelmts	- IN: Number of elements in cd_values
	cd_values	- IN: Auxiliary data for the filter

Exceptions:

H5::PropListIException

Description

The flags argument is a bit vector of the field: H5Z_FLAG_OPTIONAL(0x0001)

If this bit is set then the filter is optional. If the filter fails during a DataSet::write() operation then the filter is just excluded from the pipeline for the chunk for which it failed; the filter will not participate in the pipeline during a DataSet::read() of the chunk. If this bit is clear and the filter fails then the entire I/O operation fails.

void H5::DSetCreatPropList::setFletcher32

(

)

const

Sets Fletcher32 checksum of EDC for this property list.

Exceptions:

H5::PropListIException

void H5::DSetCreatPropList::setShuffle

(

)

const

Sets method of the shuffle filter.

Exceptions:

H5::PropListIException

Description

Please refer to the Reference Manual of H5Pset_shuffle for details. ../RM_H5P.html::Property-SetShuffle

void H5::DSetCreatPropList::setSzip	(	unsigned int	options_mask,
		unsigned int	pixels_per_block
	)			const

Sets up for the use of the SZIP compression filter.

Parameters:

	options_mask	- IN: A bit-mask conveying the desired SZIP options. Valid values are H5_SZIP_EC_OPTION_MASK and H5_SZIP_NN_OPTION_MASK.
	pixels_per_block	- IN: Number of pixels or data elements in each data block.

Exceptions:

H5::PropListIException

Description

The associate C function sets an SZIP compression filter, H5Z_FILTER_SZIP, for a dataset. For more information about SZIP and usage, please refer to the C layer Reference Manual at: ../RM_H5P.html::Property-SetSzip

virtual H5std_string H5::DSetCreatPropList::fromClass

(

)

const [inline, virtual]

Reimplemented from H5::PropList.

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Member Data Documentation

const DSetCreatPropList H5::DSetCreatPropList::DEFAULT [static]

Constant for dataset creation default property.

Reimplemented from H5::PropList.

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