Learn About a Variable

Learn variable name, dimensions, and type in C. More...

Functions
int	PIOc_inq_var (int ncid, int varid, char *name, nc_type *xtypep, int *ndimsp, int *dimidsp, int *nattsp)
	The PIO-C interface for the NetCDF function nc_inq_var. More...
int	PIOc_inq_varname (int ncid, int varid, char *name)
	Get the name of a variable. More...
int	PIOc_inq_vartype (int ncid, int varid, nc_type *xtypep)
	Find the type of a variable. More...
int	PIOc_inq_varndims (int ncid, int varid, int *ndimsp)
	Find the number of dimensions of a variable. More...
int	PIOc_inq_vardimid (int ncid, int varid, int *dimidsp)
	Find the dimension IDs associated with a variable. More...
int	PIOc_inq_varnatts (int ncid, int varid, int *nattsp)
	Find the number of attributes associated with a variable. More...
int	PIOc_inq_varid (int ncid, const char *name, int *varidp)
	The PIO-C interface for the NetCDF function nc_inq_varid. More...
int	PIOc_inq_var_fill (int ncid, int varid, int *no_fill, void *fill_valuep)
	The PIO-C interface for the NetCDF function nc_inq_var_fill. 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_inq_var_chunking (int ncid, int varid, int *storagep, PIO_Offset *chunksizesp)
	Inquire about 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_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

Learn variable name, dimensions, and type in C.

Function Documentation

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. Ignored if NULL.
nelemsp	will get the number of elements in the cache. Ignored if NULL.
preemptionp	will get the cache preemption value. Ignored if NULL.

Returns

PIO_NOERR for success, otherwise an error code.

Author

Ed Hartnett

PIOc_inq_var()

int PIOc_inq_var	(	int	ncid,
		int	varid,
		char *	name,
		nc_type *	xtypep,
		int *	ndimsp,
		int *	dimidsp,
		int *	nattsp
	)

The PIO-C interface for the NetCDF function nc_inq_var.

This routine is called collectively by all tasks in the communicator ios.union_comm. For more information on the underlying NetCDF commmand please read about this function in the NetCDF documentation at: http://www.unidata.ucar.edu/software/netcdf/docs/group__variables.html

Parameters

ncid	the ncid of the open file, obtained from PIOc_openfile() or PIOc_createfile().
varid	the variable ID.
name	a pointer that gets the name of the dimension. Igorned if NULL. Name will be PIO_MAX_NAME chars or fewer.
xtypep	a pointer that will get the type of the attribute. Ignored if NULL.
ndimsp	a pointer that will get the number of dimensions. Ignored if NULL.
dimidsp	a pointer that will get an array of dimids. Ignored if NULL.
nattsp	a pointer that will get the number of attributes. Ignored if NULL.

Returns

PIO_NOERR for success, error code otherwise.

Author

Jim Edwards, Ed Hartnett

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.
chunksizesp	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.

Author

Ed Hartnett

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. Ignored if NULL.
deflatep	pointer to an int that will be set to non-zero if deflation is in use for this variable. Ignored if NULL.
deflate_levelp	pointer to an int that will get the deflation level (from 1-9) if deflation is in use for this variable. Ignored if NULL.

Returns

PIO_NOERR for success, otherwise an error code.

Author

Ed Hartnett

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.
endianp	pointer to int which will be set to endianness. Ignored if NULL.

Returns

PIO_NOERR for success, otherwise an error code.

Author

Ed Hartnett

PIOc_inq_var_fill()

int PIOc_inq_var_fill	(	int	ncid,
		int	varid,
		int *	no_fill,
		void *	fill_valuep
	)

The PIO-C interface for the NetCDF function nc_inq_var_fill.

This routine is called collectively by all tasks in the communicator ios.union_comm. For more information on the underlying NetCDF commmand please read about this function in the NetCDF documentation at: http://www.unidata.ucar.edu/software/netcdf/docs/group__variables.html

Parameters

ncid	the ncid of the open file, obtained from PIOc_openfile() or PIOc_createfile().
varid	the variable ID.
no_fill	a pointer to int that will get the fill mode. Ignored if NULL (except with pnetcdf, which seg-faults with NULL.)
fill_valuep	pointer to space that gets the fill value for this variable. Ignored if NULL.

Returns

PIO_NOERR for success, error code otherwise.

Author

Jim Edwards, Ed Hartnett

PIOc_inq_vardimid()

int PIOc_inq_vardimid	(	int	ncid,
		int	varid,
		int *	dimidsp
	)

Find the dimension IDs associated with a variable.

Parameters

ncid	the ncid of the open file.
varid	the variable ID.
dimidsp	a pointer that will get an array of dimids. Ignored if NULL.

Returns

PIO_NOERR for success, error code otherwise.

Author

Jim Edwards, Ed Hartnett

PIOc_inq_varid()

int PIOc_inq_varid	(	int	ncid,
		const char *	name,
		int *	varidp
	)

The PIO-C interface for the NetCDF function nc_inq_varid.

This routine is called collectively by all tasks in the communicator ios.union_comm. For more information on the underlying NetCDF commmand please read about this function in the NetCDF documentation at: http://www.unidata.ucar.edu/software/netcdf/docs/group__variables.html

Parameters

ncid	the ncid of the open file, obtained from PIOc_openfile() or PIOc_createfile().
name	the variable name.
varidp	a pointer that will get the variable id

Returns

PIO_NOERR for success, error code otherwise. See PIOc_Set_File_Error_Handling

Author

Jim Edwards, Ed Hartnett

PIOc_inq_varname()

int PIOc_inq_varname	(	int	ncid,
		int	varid,
		char *	name
	)

Get the name of a variable.

Parameters

ncid	the ncid of the open file.
varid	the variable ID.
name	a pointer that will get the variable name.

Returns

PIO_NOERR for success, error code otherwise.

Author

Jim Edwards, Ed Hartnett

PIOc_inq_varnatts()

int PIOc_inq_varnatts	(	int	ncid,
		int	varid,
		int *	nattsp
	)

Find the number of attributes associated with a variable.

Parameters

ncid	the ncid of the open file.
varid	the variable ID.
nattsp	a pointer that will get the number of attriburtes. Ignored if NULL.

Returns

PIO_NOERR for success, error code otherwise.

Author

Jim Edwards, Ed Hartnett

PIOc_inq_varndims()

int PIOc_inq_varndims	(	int	ncid,
		int	varid,
		int *	ndimsp
	)

Find the number of dimensions of a variable.

Parameters

ncid	the ncid of the open file.
varid	the variable ID.
ndimsp	a pointer that will get the number of dimensions. Ignored if NULL.

Returns

PIO_NOERR for success, error code otherwise.

Author

Jim Edwards, Ed Hartnett

PIOc_inq_vartype()

int PIOc_inq_vartype	(	int	ncid,
		int	varid,
		nc_type *	xtypep
	)

Find the type of a variable.

Parameters

ncid	the ncid of the open file.
varid	the variable ID.
xtypep	a pointer that will get the type of the attribute. Ignored if NULL.

Returns

PIO_NOERR for success, error code otherwise.

Author

Jim Edwards, Ed Hartnett