Functions to wrap netCDF-4 functions for PIO. More...

#include <pio.h>
#include <pio_internal.h>

Functions
int	PIOc_def_var_deflate (int ncid, int varid, int shuffle, int deflate, int deflate_level)
	Set deflate (zlib) settings for a variable. More...

int	PIOc_inq_var_deflate (int ncid, int varid, int shufflep, int deflatep, int *deflate_levelp)
	This function only applies to netCDF-4 files. More...

int	PIOc_def_var_chunking (int ncid, int varid, int storage, const PIO_Offset *chunksizesp)
	Set chunksizes for a variable. More...

int	PIOc_inq_var_chunking (int ncid, int varid, int storagep, PIO_Offset chunksizesp)
	Inquire about chunksizes for a variable. More...

int	PIOc_def_var_fill (int ncid, int varid, int no_fill, const void *fill_value)
	Set chunksizes for a variable. More...

int	PIOc_def_var_endian (int ncid, int varid, int endian)
	Set chunksizes for a variable. More...

int	PIOc_inq_var_endian (int ncid, int varid, int *endianp)
	Inquire about chunksizes for a variable. More...

int	PIOc_set_chunk_cache (int iosysid, int iotype, PIO_Offset size, PIO_Offset nelems, float preemption)
	Set chunk cache netCDF files to be opened/created. More...

int	PIOc_get_chunk_cache (int iosysid, int iotype, PIO_Offset sizep, PIO_Offset nelemsp, float *preemptionp)
	Get current file chunk cache settings from HDF5. More...

int	PIOc_set_var_chunk_cache (int ncid, int varid, PIO_Offset size, PIO_Offset nelems, float preemption)
	Set chunksizes for a variable. More...

int	PIOc_get_var_chunk_cache (int ncid, int varid, PIO_Offset sizep, PIO_Offset nelemsp, float *preemptionp)
	Get the variable chunk cache settings. More...

Detailed Description

Functions to wrap netCDF-4 functions for PIO.

Function Documentation

§ PIOc_def_var_chunking()

int PIOc_def_var_chunking	(	int	ncid,
		int	varid,
		int	storage,
		const PIO_Offset *	chunksizesp
	)

Set chunksizes for a variable.

This function only applies to netCDF-4 files. When used with netCDF classic files, the error PIO_ENOTNC4 will be returned.

Chunksizes have important performance repercussions. NetCDF attempts to choose sensible chunk sizes by default, but for best performance check chunking against access patterns.

See the netCDF variable documentation for details about the operation of this function.

Parameters

ncid	the ncid of the open file.
varid	the ID of the variable to set chunksizes for.
storage	NC_CONTIGUOUS or NC_CHUNKED.
chunksizep	an array of chunksizes. Must have a chunksize for every variable dimension.

Returns: PIO_NOERR for success, otherwise an error code.

Pointer to io system information.

Pointer to file information.

Return code from function calls.

Return code from MPI function codes.

§ PIOc_def_var_deflate()

int PIOc_def_var_deflate	(	int	ncid,
		int	varid,
		int	shuffle,
		int	deflate,
		int	deflate_level
	)

Set deflate (zlib) settings for a variable.

This function only applies to netCDF-4 files. When used with netCDF classic files, the error PIO_ENOTNC4 will be returned.

See the netCDF variable documentation for details about the operation of this function.

Parameters

ncid	the ncid of the open file.
varid	the ID of the variable.
shuffle	non-zero to turn on shuffle filter (can be good for integer data).
deflate	non-zero to turn on zlib compression for this variable.
deflate_level	1 to 9, with 1 being faster and 9 being more compressed.

Returns: PIO_NOERR for success, otherwise an error code.

§ PIOc_def_var_endian()

int PIOc_def_var_endian	(	int	ncid,
		int	varid,
		int	endian
	)

Set chunksizes for a variable.

This function only applies to netCDF-4 files. When used with netCDF classic files, the error PIO_ENOTNC4 will be returned.

See the netCDF variable documentation for details about the operation of this function.

Chunksizes have important performance repercussions. NetCDF attempts to choose sensible chunk sizes by default, but for best performance check chunking against access patterns.

Parameters

ncid	the ncid of the open file.
varid	the ID of the variable to set chunksizes for.
storage	NC_CONTIGUOUS or NC_CHUNKED.
chunksizep	an array of chunksizes. Must have a chunksize for every variable dimension.

Returns: PIO_NOERR for success, otherwise an error code.

§ PIOc_def_var_fill()

int PIOc_def_var_fill	(	int	ncid,
		int	varid,
		int	no_fill,
		const void *	fill_value
	)

Set chunksizes for a variable.

This function only applies to netCDF-4 files. When used with netCDF classic files, the error PIO_ENOTNC4 will be returned.

See the netCDF variable documentation for details about the operation of this function.

Chunksizes have important performance repercussions. NetCDF attempts to choose sensible chunk sizes by default, but for best performance check chunking against access patterns.

Parameters

ncid	the ncid of the open file.
varid	the ID of the variable to set chunksizes for.
storage	NC_CONTIGUOUS or NC_CHUNKED.
chunksizep	an array of chunksizes. Must have a chunksize for every variable dimension.

Returns: PIO_NOERR for success, otherwise an error code.

§ PIOc_get_chunk_cache()

int PIOc_get_chunk_cache	(	int	iosysid,
		int	iotype,
		PIO_Offset *	sizep,
		PIO_Offset *	nelemsp,
		float *	preemptionp
	)

Get current file chunk cache settings from HDF5.

This function has no effect on netCDF classic files. Calling this function with iotype of PIO_IOTYPE_PNETCDF or PIO_IOTYPE_NETCDF returns an error.

The file chunk cache for HDF5 can be set, and will apply for any files opened or created until the program ends, or the settings are changed again. The cache settings apply only to the open file. They do not persist with the file, and must be set each time the file is opened, before it is opened, if they are to have effect.

See the netCDF variable documentation for details about the operation of this function.

Chunksizes have important performance repercussions. NetCDF attempts to choose sensible chunk sizes by default, but for best performance check chunking against access patterns.

Parameters

iotype	the iotype of files to be created or opened.
sizep	gets the size of file cache.
nelemsp	gets the number of elements in file cache.
preemptionp	gets the preemption setting for file cache.

Returns: PIO_NOERR for success, otherwise an error code.

§ PIOc_get_var_chunk_cache()

int PIOc_get_var_chunk_cache	(	int	ncid,
		int	varid,
		PIO_Offset *	sizep,
		PIO_Offset *	nelemsp,
		float *	preemptionp
	)

Get the variable chunk cache settings.

This function only applies to netCDF-4 files. When used with netCDF classic files, the error PIO_ENOTNC4 will be returned.

Note that these settings are not part of the data file - they apply only to the open file as long as it is open.

See the netCDF variable documentation for details about the operation of this function.

Parameters

ncid	the ncid of the open file.
varid	the ID of the variable to set chunksizes for.
sizep	will get the size of the cache in bytes.
nelemsp	will get the number of elements in the cache.
preemptionp	will get the cache preemption value.

Returns: PIO_NOERR for success, otherwise an error code.

§ PIOc_inq_var_chunking()

int PIOc_inq_var_chunking	(	int	ncid,
		int	varid,
		int *	storagep,
		PIO_Offset *	chunksizesp
	)

Inquire about chunksizes for a variable.

This function only applies to netCDF-4 files. When used with netCDF classic files, the error PIO_ENOTNC4 will be returned.

See the netCDF variable documentation for details about the operation of this function.

Parameters

ncid	the ncid of the open file.
varid	the ID of the variable to set chunksizes for.
storagep	pointer to int which will be set to either NC_CONTIGUOUS or NC_CHUNKED.
chunksizep	pointer to memory where chunksizes will be set. There are the same number of chunksizes as there are dimensions.

Returns: PIO_NOERR for success, otherwise an error code.

§ PIOc_inq_var_deflate()

int PIOc_inq_var_deflate	(	int	ncid,
		int	varid,
		int *	shufflep,
		int *	deflatep,
		int *	deflate_levelp
	)

This function only applies to netCDF-4 files.

When used with netCDF classic files, the error PIO_ENOTNC4 will be returned.

Inquire about deflate (zlib compression) settings for a variable.

See the netCDF variable documentation for details about the operation of this function.

Parameters

ncid	the ncid of the open file.
varid	the ID of the variable to set chunksizes for.
shufflep	pointer to an int that will get the status of the shuffle filter.
deflatep	pointer to an int that will be set to non-zero if deflation is in use for this variable.
deflate_levelp	pointer to an int that will get the deflation level (from 1-9) if deflation is in use for this variable.

Returns: PIO_NOERR for success, otherwise an error code.

§ PIOc_inq_var_endian()

int PIOc_inq_var_endian	(	int	ncid,
		int	varid,
		int *	endianp
	)

Inquire about chunksizes for a variable.

This function only applies to netCDF-4 files. When used with netCDF classic files, the error PIO_ENOTNC4 will be returned.

See the netCDF variable documentation for details about the operation of this function.

Parameters

ncid	the ncid of the open file.
varid	the ID of the variable to set chunksizes for.
storagep	pointer to int which will be set to either NC_CONTIGUOUS or NC_CHUNKED.
chunksizep	pointer to memory where chunksizes will be set. There are the same number of chunksizes as there are dimensions.

Returns: PIO_NOERR for success, otherwise an error code.

§ PIOc_set_chunk_cache()

int PIOc_set_chunk_cache	(	int	iosysid,
		int	iotype,
		PIO_Offset	size,
		PIO_Offset	nelems,
		float	preemption
	)

Set chunk cache netCDF files to be opened/created.

This function only applies to netCDF-4 files. When used with netCDF classic files, the error PIO_ENOTNC4 will be returned.

The file chunk cache for HDF5 can be set, and will apply for any files opened or created until the program ends, or the settings are changed again. The cache settings apply only to the open file. They do not persist with the file, and must be set each time the file is opened, before it is opened, if they are to have effect.

See the netCDF variable documentation for details about the operation of this function.

Parameters

iotype	the iotype of files to be created or opened.
size	size of file cache.
nelems	number of elements in file cache.
preemption	preemption setting for file cache.

Returns: PIO_NOERR for success, otherwise an error code.

§ PIOc_set_var_chunk_cache()

int PIOc_set_var_chunk_cache	(	int	ncid,
		int	varid,
		PIO_Offset	size,
		PIO_Offset	nelems,
		float	preemption
	)

Set chunksizes for a variable.

This function only applies to netCDF-4 files. When used with netCDF classic files, the error PIO_ENOTNC4 will be returned.

See the netCDF variable documentation for details about the operation of this function.

Chunksizes have important performance repercussions. NetCDF attempts to choose sensible chunk sizes by default, but for best performance check chunking against access patterns.

Parameters

ncid	the ncid of the open file.
varid	the ID of the variable to set chunksizes for.
storage	NC_CONTIGUOUS or NC_CHUNKED.
chunksizep	an array of chunksizes. Must have a chunksize for every variable dimension.

Returns: PIO_NOERR for success, otherwise an error code.