NetCDF utilities

Classes
struct	dg::file::NC_Error
	Class thrown by the NC_Error_Handle. More...
struct	dg::file::NC_Error_Handle
	Empty utitlity class that handles return values of netcdf functions and throws NC_Error(status) if( status != NC_NOERR) More...

Functions
template<class host_vector >
void	dg::file::put_var_double (int ncid, int varid, const dg::aTopology2d &grid, const host_vector &data, bool parallel=false)
	Convenience wrapper around nc_put_vara_double() More...
template<class host_vector >
void	dg::file::put_vara_double (int ncid, int varid, unsigned slice, const dg::aTopology2d &grid, const host_vector &data, bool parallel=false)
	Convenience wrapper around nc_put_vara_double() More...
template<class host_vector >
void	dg::file::put_var_double (int ncid, int varid, const dg::aTopology3d &grid, const host_vector &data, bool parallel=false)
	Convenience wrapper around nc_put_vara_double() More...
template<class host_vector >
void	dg::file::put_vara_double (int ncid, int varid, unsigned slice, const dg::aTopology3d &grid, const host_vector &data, bool parallel=false)
	Convenience wrapper around nc_put_vara_double() More...
template<class host_vector >
void	dg::file::put_var_double (int ncid, int varid, const dg::aMPITopology2d &grid, const dg::MPI_Vector< host_vector > &data, bool parallel=false)
	Convenience wrapper around nc_put_vara_double() More...
template<class host_vector >
void	dg::file::put_vara_double (int ncid, int varid, unsigned slice, const dg::aMPITopology2d &grid, const dg::MPI_Vector< host_vector > &data, bool parallel=false)
	Convenience wrapper around nc_put_vara_double() More...
template<class host_vector >
void	dg::file::put_var_double (int ncid, int varid, const dg::aMPITopology3d &grid, const dg::MPI_Vector< host_vector > &data, bool parallel=false)
	Convenience wrapper around nc_put_vara_double() More...
template<class host_vector >
void	dg::file::put_vara_double (int ncid, int varid, unsigned slice, const dg::aMPITopology3d &grid, const dg::MPI_Vector< host_vector > &data, bool parallel=false)
	Convenience wrapper around nc_put_vara_double() More...
template<class T >
int	dg::file::define_real_time (int ncid, const char *name, int *dimID, int *tvarID)
	Define an unlimited time dimension and coordinate variable. More...
static int	dg::file::define_time (int ncid, const char *name, int *dimID, int *tvarID)
	Define an unlimited time dimension and coordinate variable. More...
static int	dg::file::define_limited_time (int ncid, const char *name, int size, int *dimID, int *tvarID)
	Define a limited time dimension and coordinate variable. More...
template<class T >
int	dg::file::define_dimension (int ncid, int *dimID, const dg::RealGrid1d< T > &g, std::string name_dim="x", std::string axis="X")
	Define a 1d dimension and associated coordinate variable. More...
template<class T >
int	dg::file::define_dimensions (int ncid, int *dimsIDs, int *tvarID, const dg::RealGrid1d< T > &g, std::array< std::string, 2 > name_dims={"time","x"})
	Define an unlimited time and a dimension together with their coordinate variables. More...
template<class T >
int	dg::file::define_dimensions (int ncid, int *dimsIDs, const dg::aRealTopology2d< T > &g, std::array< std::string, 2 > name_dims={"y", "x"})
	Define 2 dimensions and associated coordiante variables. More...
template<class T >
int	dg::file::define_dimensions (int ncid, int *dimsIDs, int *tvarID, const dg::aRealTopology2d< T > &g, std::array< std::string, 3 > name_dims={"time", "y", "x"})
	Define an unlimited time and 2 dimensions and associated coordinate variables. More...
template<class T >
int	dg::file::define_limtime_xy (int ncid, int *dimsIDs, int size, int *tvarID, const dg::aRealTopology2d< T > &g, std::array< std::string, 3 > name_dims={"time", "y", "x"})
	Define a limited time and 2 dimensions and associated coordinate variables. More...
template<class T >
int	dg::file::define_dimensions (int ncid, int *dimsIDs, const dg::aRealTopology3d< T > &g, std::array< std::string, 3 > name_dims={"z", "y", "x"})
	Define 3 dimensions and associated coordinate variables. More...
template<class T >
int	dg::file::define_dimensions (int ncid, int *dimsIDs, int *tvarID, const dg::aRealTopology3d< T > &g, std::array< std::string, 4 > name_dims={"time", "z", "y", "x"})
	Define an unlimited time and 3 dimensions together with their coordinate varariables. More...
template<class T >
int	dg::file::define_dimensions (int ncid, int *dimsIDs, const dg::aRealMPITopology2d< T > &g, std::array< std::string, 2 > name_dims={"y", "x"})
	Only master process should call this!! Convenience function that just calls the corresponding serial version with the global grid.
template<class T >
int	dg::file::define_dimensions (int ncid, int *dimsIDs, int *tvarID, const dg::aRealMPITopology2d< T > &g, std::array< std::string, 3 > name_dims={"time", "y", "x"})
	Only master process should call this!! Convenience function that just calls the corresponding serial version with the global grid.
template<class T >
int	dg::file::define_dimensions (int ncid, int *dimsIDs, const dg::aRealMPITopology3d< T > &g, std::array< std::string, 3 > name_dims={"z", "y", "x"})
	Only master process should call this!! Convenience function that just calls the corresponding serial version with the global grid.
template<class T >
int	dg::file::define_dimensions (int ncid, int *dimsIDs, int *tvarID, const dg::aRealMPITopology3d< T > &g, std::array< std::string, 4 > name_dims={"time", "z", "y", "x"})
	Only master process should call this!! Convenience function that just calls the corresponding serial version with the global grid.

Detailed Description

#include "dg/file/nc_utilities.h" (link -lnetcdf -lhdf5[_serial] -lhdf5[_serial]_hl)

Function Documentation

define_dimension()

template<class T >

int dg::file::define_dimension ( int  ncid, int *  dimID, const dg::RealGrid1d< T > &  g, std::string  name_dim = "x", std::string  axis = "X"  )

inline

Define a 1d dimension and associated coordinate variable.

Note

By netCDF conventions a variable with the same name as a dimension is called a coordinate variable.

Parameters

ncid	file ID
dimID	dimension ID (output)
g	The 1d DG grid from which data points for coordinate variable are generated using dg::create::abscissas(g)
name_dim	Name of dimension and coordinate variable (input)
axis	The axis attribute (input), ("X", "Y" or "Z")

Template Parameters

T	determines the datatype of the dimension variables

Returns

NetCDF error code if any

define_dimensions() [1/5]

template<class T >

int dg::file::define_dimensions ( int  ncid, int *  dimsIDs, const dg::aRealTopology2d< T > &  g, std::array< std::string, 2 >  name_dims = {"y", "x"}  )

inline

Define 2 dimensions and associated coordiante variables.

Note

By netCDF conventions a variable with the same name as a dimension is called a coordinate variable.

Dimensions have attributes of (Y, X)

Parameters

ncid	file ID
dimsIDs	(write - only) 2D array of dimension IDs (Y,X)
g	The 2d DG grid from which data points for coordinate variable are generated using dg::create::abscissas(g) in each dimension
name_dims	Names for the dimension variables

Template Parameters

T	determines the datatype of the dimension variables

Returns

if anything goes wrong it returns the netCDF code, else SUCCESS

Note

File stays in define mode

define_dimensions() [2/5]

template<class T >

int dg::file::define_dimensions ( int  ncid, int *  dimsIDs, const dg::aRealTopology3d< T > &  g, std::array< std::string, 3 >  name_dims = {"z", "y", "x"}  )

inline

Define 3 dimensions and associated coordinate variables.

Note

By netCDF conventions a variable with the same name as a dimension is called a coordinate variable.

Dimensions have attributes ( Z, Y, X)

Parameters

ncid	file ID
dimsIDs	(write - only) 3D array of dimension IDs (Z,Y,X)
g	The 3d DG grid from which data points for coordinate variable are generated using dg::create::abscissas(g) in each dimension
name_dims	Names for the dimension variables ( Z, Y, X)

Template Parameters

T	determines the datatype of the dimension variables

Returns

if anything goes wrong it returns the netCDF code, else SUCCESS

Note

File stays in define mode

define_dimensions() [3/5]

template<class T >

int dg::file::define_dimensions ( int  ncid, int *  dimsIDs, int *  tvarID, const dg::aRealTopology2d< T > &  g, std::array< std::string, 3 >  name_dims = {"time", "y", "x"}  )

inline

Define an unlimited time and 2 dimensions and associated coordinate variables.

Note

By netCDF conventions a variable with the same name as a dimension is called a coordinate variable.

Semantically equivalent to the following:

define_time( ncid, name_dims[0], &dimsIDs[0], tvarID);
define_dimensions( ncid, &dimsIDs[1], g, {name_dims[1], name_dims[2]});

Dimensions have attributes of (time, Y, X)

Parameters

ncid	file ID
dimsIDs	(write - only) 3D array of dimension IDs (time, Y,X)
tvarID	(write - only) The ID of the time variable ( unlimited)
g	The 2d DG grid from which data points for coordinate variable are generated using dg::create::abscissas(g) in each dimension
name_dims	Names for the dimension variables ( time, Y, X)

Template Parameters

T	determines the datatype of the dimension variables

Returns

if anything goes wrong it returns the netCDF code, else SUCCESS

Note

File stays in define mode

define_dimensions() [4/5]

template<class T >

int dg::file::define_dimensions ( int  ncid, int *  dimsIDs, int *  tvarID, const dg::aRealTopology3d< T > &  g, std::array< std::string, 4 >  name_dims = {"time", "z", "y", "x"}  )

inline

Define an unlimited time and 3 dimensions together with their coordinate varariables.

Note

By netCDF conventions a variable with the same name as a dimension is called a coordinate variable.

Semantically equivalent to the following:

define_time( ncid, name_dims[0], &dimsIDs[0], tvarID);
define_dimensions( ncid, &dimsIDs[1], g, {name_dims[1], name_dims[2], name_dims[3]});

Dimensions have attributes ( time, Z, Y, X)

Parameters

ncid	file ID
dimsIDs	(write - only) 4D array of dimension IDs (time, Z,Y,X)
tvarID	(write - only) The ID of the time variable ( unlimited)
g	The 3d DG grid from which data points for coordinate variable are generated using dg::create::abscissas(g) in each dimension
name_dims	Names for the dimension variables ( time, Z, Y, X)

Template Parameters

T	determines the datatype of the dimension variables

Returns

if anything goes wrong it returns the netCDF code, else SUCCESS

Note

File stays in define mode

define_dimensions() [5/5]

template<class T >

int dg::file::define_dimensions ( int  ncid, int *  dimsIDs, int *  tvarID, const dg::RealGrid1d< T > &  g, std::array< std::string, 2 >  name_dims = {"time","x"}  )

inline

Define an unlimited time and a dimension together with their coordinate variables.

Note

By netCDF conventions a variable with the same name as a dimension is called a coordinate variable.

Semantically equivalent to the following:

define_time( ncid, name_dims[0], &dimsIDs[0], tvarID);
define_dimension( ncid, &dimsIDs[1], g, name_dims[1]);

Dimensions have attribute of (time, X)

Parameters

ncid	file ID
dimsIDs	dimension IDs (time, X)
tvarID	time coordinate variable ID (unlimited)
g	The 1d DG grid from which data points for coordinate variable are generated using dg::create::abscissas(g)
name_dims	Names for the dimension and coordinate variables

Template Parameters

T	determines the datatype of the dimension variables

Returns

NetCDF error code if any

define_limited_time()

static int dg::file::define_limited_time ( int  ncid, const char *  name, int  size, int *  dimID, int *  tvarID  )

inlinestatic

Define a limited time dimension and coordinate variable.

Note

By netCDF conventions a variable with the same name as a dimension is called a coordinate variable. The CF conventions dictate that the units attribute must be defined for a time variable: we give it the value "time since start"

Parameters

ncid	file ID
name	Name of the time variable (usually "time")
size	The number of timesteps
dimID	time-dimension ID
tvarID	time-variable ID (for a time variable of type NC_DOUBLE)

Returns

NetCDF error code if any

define_limtime_xy()

template<class T >

int dg::file::define_limtime_xy ( int  ncid, int *  dimsIDs, int  size, int *  tvarID, const dg::aRealTopology2d< T > &  g, std::array< std::string, 3 >  name_dims = {"time", "y", "x"}  )

inline

Define a limited time and 2 dimensions and associated coordinate variables.

Note

By netCDF conventions a variable with the same name as a dimension is called a coordinate variable.

Semantically equivalent to the following:

define_limited_time( ncid, name_dims[0], size, &dimsIDs[0], tvarID);
define_dimensions( ncid, &dimsIDs[1], g, {name_dims[1], name_dims[2]});

Dimensions have attributes of (time, Y, X)

Parameters

ncid	file ID
dimsIDs	(write - only) 3D array of dimension IDs (time, Y,X)
size	The size of the time variable
tvarID	(write - only) The ID of the time variable (limited)
g	The 2d DG grid from which data points for coordinate variable are generated using dg::create::abscissas(g)
name_dims	Names for the dimension variables (time, Y, X)

Template Parameters

T	determines the datatype of the dimension variables

Returns

if anything goes wrong it returns the netCDF code, else SUCCESS

Note

File stays in define mode

define_real_time()

template<class T >

int dg::file::define_real_time ( int  ncid, const char *  name, int *  dimID, int *  tvarID  )

inline

Define an unlimited time dimension and coordinate variable.

Note

By netCDF conventions a variable with the same name as a dimension is called a coordinate variable. The CF conventions dictate that the units attribute must be defined for a time variable: we give it the value "time since start"

Parameters

ncid	file ID
name	Name of time variable (variable names are not standardized)
dimID	time-dimension ID
tvarID	time-variable ID (for a time variable of type NC_DOUBLE)

Returns

NetCDF error code if any

define_time()

static int dg::file::define_time ( int  ncid, const char *  name, int *  dimID, int *  tvarID  )

inlinestatic

Define an unlimited time dimension and coordinate variable.

Note

By netCDF conventions a variable with the same name as a dimension is called a coordinate variable. The CF conventions dictate that the units attribute must be defined for a time variable: we give it the value "time since start"

Parameters

ncid	file ID
name	Name of time variable (variable names are not standardized)
dimID	time-dimension ID
tvarID	time-variable ID (for a time variable of type NC_DOUBLE)

Returns

NetCDF error code if any

put_var_double() [1/4]

template<class host_vector >

void dg::file::put_var_double	(	int	ncid,
		int	varid,
		const dg::aMPITopology2d &	grid,
		const dg::MPI_Vector< host_vector > &	data,
		bool	parallel = false
	)

Convenience wrapper around nc_put_vara_double()

The purpose of this function is mainly to simplify output in an MPI environment and to provide the same interface also in a shared memory system for uniform programming. This version is for a time-independent variable, i.e. writes a single variable in one go and is actually equivalent to nc_put_var_double. The dimensionality is given by the grid.

Note

This function throws a dg::file::NC_Error if an error occurs

Template Parameters

host_vector

Type with data() member that returns pointer to first element in CPU (host) adress space, meaning it cannot be a GPU vector

Parameters

ncid	Forwarded to nc_put_vara_double
varid	Forwarded to nc_put_vara_double
grid	The grid from which to construct start and count variables to forward to nc_put_vara_double
data	data is forwarded to nc_put_vara_double
parallel	This parameter is ignored in the serial version. In the MPI version this parameter indicates whether each process writes to the file independently in parallel (true) or each process funnels its data through the master rank (false), which involves communication but may be faster than the former method.

Attention

In the MPI version (i) all processes must call this function and (ii) if parallel==true a parallel netcdf and hdf5 must be linked, the file opened with the NC_MPIIO flag from the netcdf_par.h header and the variable be marked with NC_COLLECTIVE access while if parallel==false we need serial netcdf and hdf5 and only the master thread needs to open and access the file. Note that serious performance penalties have been observed on some platforms for parallel netcdf.

put_var_double() [2/4]

template<class host_vector >

void dg::file::put_var_double	(	int	ncid,
		int	varid,
		const dg::aMPITopology3d &	grid,
		const dg::MPI_Vector< host_vector > &	data,
		bool	parallel = false
	)

Convenience wrapper around nc_put_vara_double()

The purpose of this function is mainly to simplify output in an MPI environment and to provide the same interface also in a shared memory system for uniform programming. This version is for a time-independent variable, i.e. writes a single variable in one go and is actually equivalent to nc_put_var_double. The dimensionality is given by the grid.

Note

This function throws a dg::file::NC_Error if an error occurs

Template Parameters

host_vector

Type with data() member that returns pointer to first element in CPU (host) adress space, meaning it cannot be a GPU vector

Parameters

ncid	Forwarded to nc_put_vara_double
varid	Forwarded to nc_put_vara_double
grid	The grid from which to construct start and count variables to forward to nc_put_vara_double
data	data is forwarded to nc_put_vara_double
parallel	This parameter is ignored in the serial version. In the MPI version this parameter indicates whether each process writes to the file independently in parallel (true) or each process funnels its data through the master rank (false), which involves communication but may be faster than the former method.

Attention

In the MPI version (i) all processes must call this function and (ii) if parallel==true a parallel netcdf and hdf5 must be linked, the file opened with the NC_MPIIO flag from the netcdf_par.h header and the variable be marked with NC_COLLECTIVE access while if parallel==false we need serial netcdf and hdf5 and only the master thread needs to open and access the file. Note that serious performance penalties have been observed on some platforms for parallel netcdf.

put_var_double() [3/4]

template<class host_vector >

void dg::file::put_var_double	(	int	ncid,
		int	varid,
		const dg::aTopology2d &	grid,
		const host_vector &	data,
		bool	parallel = false
	)

Convenience wrapper around nc_put_vara_double()

The purpose of this function is mainly to simplify output in an MPI environment and to provide the same interface also in a shared memory system for uniform programming. This version is for a time-independent variable, i.e. writes a single variable in one go and is actually equivalent to nc_put_var_double. The dimensionality is given by the grid.

Note

This function throws a dg::file::NC_Error if an error occurs

Template Parameters

host_vector

Type with data() member that returns pointer to first element in CPU (host) adress space, meaning it cannot be a GPU vector

Parameters

ncid	Forwarded to nc_put_vara_double
varid	Forwarded to nc_put_vara_double
grid	The grid from which to construct start and count variables to forward to nc_put_vara_double
data	data is forwarded to nc_put_vara_double
parallel	This parameter is ignored in the serial version. In the MPI version this parameter indicates whether each process writes to the file independently in parallel (true) or each process funnels its data through the master rank (false), which involves communication but may be faster than the former method.

Attention

In the MPI version (i) all processes must call this function and (ii) if parallel==true a parallel netcdf and hdf5 must be linked, the file opened with the NC_MPIIO flag from the netcdf_par.h header and the variable be marked with NC_COLLECTIVE access while if parallel==false we need serial netcdf and hdf5 and only the master thread needs to open and access the file. Note that serious performance penalties have been observed on some platforms for parallel netcdf.

put_var_double() [4/4]

template<class host_vector >

void dg::file::put_var_double	(	int	ncid,
		int	varid,
		const dg::aTopology3d &	grid,
		const host_vector &	data,
		bool	parallel = false
	)

Convenience wrapper around nc_put_vara_double()

The purpose of this function is mainly to simplify output in an MPI environment and to provide the same interface also in a shared memory system for uniform programming. This version is for a time-independent variable, i.e. writes a single variable in one go and is actually equivalent to nc_put_var_double. The dimensionality is given by the grid.

Note

This function throws a dg::file::NC_Error if an error occurs

Template Parameters

host_vector

Type with data() member that returns pointer to first element in CPU (host) adress space, meaning it cannot be a GPU vector

Parameters

ncid	Forwarded to nc_put_vara_double
varid	Forwarded to nc_put_vara_double
grid	The grid from which to construct start and count variables to forward to nc_put_vara_double
data	data is forwarded to nc_put_vara_double
parallel	This parameter is ignored in the serial version. In the MPI version this parameter indicates whether each process writes to the file independently in parallel (true) or each process funnels its data through the master rank (false), which involves communication but may be faster than the former method.

Attention

In the MPI version (i) all processes must call this function and (ii) if parallel==true a parallel netcdf and hdf5 must be linked, the file opened with the NC_MPIIO flag from the netcdf_par.h header and the variable be marked with NC_COLLECTIVE access while if parallel==false we need serial netcdf and hdf5 and only the master thread needs to open and access the file. Note that serious performance penalties have been observed on some platforms for parallel netcdf.

put_vara_double() [1/4]

template<class host_vector >

void dg::file::put_vara_double	(	int	ncid,
		int	varid,
		unsigned	slice,
		const dg::aMPITopology2d &	grid,
		const dg::MPI_Vector< host_vector > &	data,
		bool	parallel = false
	)

Convenience wrapper around nc_put_vara_double()

The purpose of this function is mainly to simplify output in an MPI environment and to provide the same interface also in a shared memory system for uniform programming. This version is for a time-dependent variable, i.e. writes a single time-slice into the file. The dimensionality is given by the grid.

Note

This function throws a dg::file::NC_Error if an error occurs

Template Parameters

host_vector

Type with data() member that returns pointer to first element in CPU (host) adress space, meaning it cannot be a GPU vector

Parameters

ncid	Forwarded to nc_put_vara_double
varid	Forwarded to nc_put_vara_double
slice	The number of the time-slice to write (first element of the startp array in nc_put_vara_double)
grid	The grid from which to construct start and count variables to forward to nc_put_vara_double
data	data is forwarded to nc_put_vara_double,
parallel	This parameter is ignored in the serial version. In the MPI version this parameter indicates whether each process writes to the file independently in parallel (true) or each process funnels its data through the master rank (false), which involves communication but may be faster than the former method.

Attention

In the MPI version (i) all processes must call this function and (ii) if parallel==true a parallel netcdf and hdf5 must be linked, the file opened with the NC_MPIIO flag from the netcdf_par.h header and the variable be marked with NC_COLLECTIVE access while if parallel==false we need serial netcdf and hdf5 and only the master thread needs to open and access the file. Note that serious performance penalties have been observed on some platforms for parallel netcdf.

put_vara_double() [2/4]

template<class host_vector >

void dg::file::put_vara_double	(	int	ncid,
		int	varid,
		unsigned	slice,
		const dg::aMPITopology3d &	grid,
		const dg::MPI_Vector< host_vector > &	data,
		bool	parallel = false
	)

Convenience wrapper around nc_put_vara_double()

The purpose of this function is mainly to simplify output in an MPI environment and to provide the same interface also in a shared memory system for uniform programming. This version is for a time-dependent variable, i.e. writes a single time-slice into the file. The dimensionality is given by the grid.

Note

This function throws a dg::file::NC_Error if an error occurs

Template Parameters

host_vector

Type with data() member that returns pointer to first element in CPU (host) adress space, meaning it cannot be a GPU vector

Parameters

ncid	Forwarded to nc_put_vara_double
varid	Forwarded to nc_put_vara_double
slice	The number of the time-slice to write (first element of the startp array in nc_put_vara_double)
grid	The grid from which to construct start and count variables to forward to nc_put_vara_double
data	data is forwarded to nc_put_vara_double,
parallel	This parameter is ignored in the serial version. In the MPI version this parameter indicates whether each process writes to the file independently in parallel (true) or each process funnels its data through the master rank (false), which involves communication but may be faster than the former method.

Attention

In the MPI version (i) all processes must call this function and (ii) if parallel==true a parallel netcdf and hdf5 must be linked, the file opened with the NC_MPIIO flag from the netcdf_par.h header and the variable be marked with NC_COLLECTIVE access while if parallel==false we need serial netcdf and hdf5 and only the master thread needs to open and access the file. Note that serious performance penalties have been observed on some platforms for parallel netcdf.

put_vara_double() [3/4]

template<class host_vector >

void dg::file::put_vara_double	(	int	ncid,
		int	varid,
		unsigned	slice,
		const dg::aTopology2d &	grid,
		const host_vector &	data,
		bool	parallel = false
	)

Convenience wrapper around nc_put_vara_double()

The purpose of this function is mainly to simplify output in an MPI environment and to provide the same interface also in a shared memory system for uniform programming. This version is for a time-dependent variable, i.e. writes a single time-slice into the file. The dimensionality is given by the grid.

Note

This function throws a dg::file::NC_Error if an error occurs

Template Parameters

host_vector

Type with data() member that returns pointer to first element in CPU (host) adress space, meaning it cannot be a GPU vector

Parameters

ncid	Forwarded to nc_put_vara_double
varid	Forwarded to nc_put_vara_double
slice	The number of the time-slice to write (first element of the startp array in nc_put_vara_double)
grid	The grid from which to construct start and count variables to forward to nc_put_vara_double
data	data is forwarded to nc_put_vara_double,
parallel	This parameter is ignored in the serial version. In the MPI version this parameter indicates whether each process writes to the file independently in parallel (true) or each process funnels its data through the master rank (false), which involves communication but may be faster than the former method.

Attention

In the MPI version (i) all processes must call this function and (ii) if parallel==true a parallel netcdf and hdf5 must be linked, the file opened with the NC_MPIIO flag from the netcdf_par.h header and the variable be marked with NC_COLLECTIVE access while if parallel==false we need serial netcdf and hdf5 and only the master thread needs to open and access the file. Note that serious performance penalties have been observed on some platforms for parallel netcdf.

put_vara_double() [4/4]

template<class host_vector >

void dg::file::put_vara_double	(	int	ncid,
		int	varid,
		unsigned	slice,
		const dg::aTopology3d &	grid,
		const host_vector &	data,
		bool	parallel = false
	)

Convenience wrapper around nc_put_vara_double()

The purpose of this function is mainly to simplify output in an MPI environment and to provide the same interface also in a shared memory system for uniform programming. This version is for a time-dependent variable, i.e. writes a single time-slice into the file. The dimensionality is given by the grid.

Note

This function throws a dg::file::NC_Error if an error occurs

Template Parameters

host_vector

Type with data() member that returns pointer to first element in CPU (host) adress space, meaning it cannot be a GPU vector

Parameters

ncid	Forwarded to nc_put_vara_double
varid	Forwarded to nc_put_vara_double
slice	The number of the time-slice to write (first element of the startp array in nc_put_vara_double)
grid	The grid from which to construct start and count variables to forward to nc_put_vara_double
data	data is forwarded to nc_put_vara_double,
parallel	This parameter is ignored in the serial version. In the MPI version this parameter indicates whether each process writes to the file independently in parallel (true) or each process funnels its data through the master rank (false), which involves communication but may be faster than the former method.

Attention

In the MPI version (i) all processes must call this function and (ii) if parallel==true a parallel netcdf and hdf5 must be linked, the file opened with the NC_MPIIO flag from the netcdf_par.h header and the variable be marked with NC_COLLECTIVE access while if parallel==false we need serial netcdf and hdf5 and only the master thread needs to open and access the file. Note that serious performance penalties have been observed on some platforms for parallel netcdf.