Class emulator::EmulatorIO

ClassList > emulator > EmulatorIO

Static class providing parallel I/O using SCORPIO/PIO. More...

• #include <emulator_io.hpp>

Public Static Functions

Type	Name
void	close_file (int ncid) Close an open file.
int	create_file (const std::string & filename) Create a new NetCDF file for writing.
int	define_dim (int ncid, const std::string & dimname, int length) Define a new dimension in a NetCDF file.
int	define_var (int ncid, const std::string & varname, int nctype, const std::vector< int > & dimids) Define a new variable in a NetCDF file.
bool	end_def (int ncid) End define mode and switch to data mode.
void	finalize () Finalize the PIO subsystem.
int	get_dim_size (int ncid, const std::string & dimname) Get the size of a dimension.
bool	has_var (int ncid, const std::string & varname) Check if a variable exists in the file.
void	initialize (MPI_Comm comm, const std::string & comp_name) Initialize the PIO subsystem.
bool	is_initialized () Check if PIO is initialized.
int	open_file (const std::string & filename) Open an existing NetCDF file for reading.
bool	read_var_1d (int ncid, const std::string & varname, double * data, int size) Read a 1D double array from a NetCDF variable.
bool	read_var_1d_int (int ncid, const std::string & varname, int * data, int size) Read a 1D integer array from a NetCDF variable.
bool	read_var_2d (int ncid, const std::string & varname, double * data, int nx, int ny) Read a 2D double array from a NetCDF variable.
bool	read_var_3d_slice (int ncid, const std::string & varname, double * data, int nx, int ny, int time_idx) Read a 2D slice from a 3D variable (time, lat, lon).
void	sync_file (int ncid) Synchronize (flush) file contents to disk.
bool	write_var_1d (int ncid, const std::string & varname, const double * data, int size) Write a 1D double array to a NetCDF variable.
bool	write_var_2d (int ncid, const std::string & varname, const double * data, int nx, int ny) Write a 2D double array to a NetCDF variable.

Detailed Description

Public Static Functions Documentation

function close_file

Close an open file.

static void emulator::EmulatorIO::close_file (
    int ncid
) 

Parameters:

• ncid File ID from open_file() or create_file()

---

function create_file

Create a new NetCDF file for writing.

static int emulator::EmulatorIO::create_file (
    const std::string & filename
) 

Parameters:

• filename Path to the new file

Returns:

NetCDF file ID (ncid), or -1 on failure

---

function define_dim

Define a new dimension in a NetCDF file.

static int emulator::EmulatorIO::define_dim (
    int ncid,
    const std::string & dimname,
    int length
) 

Parameters:

• ncid File ID (must be in define mode)
• dimname Dimension name
• length Dimension length

Returns:

Dimension ID, or -1 on failure

---

function define_var

Define a new variable in a NetCDF file.

static int emulator::EmulatorIO::define_var (
    int ncid,
    const std::string & varname,
    int nctype,
    const std::vector< int > & dimids
) 

Parameters:

• ncid File ID (must be in define mode)
• varname Variable name
• nctype NetCDF type (e.g., NC_DOUBLE)
• dimids Vector of dimension IDs

Returns:

Variable ID, or -1 on failure

---

function end_def

End define mode and switch to data mode.

static bool emulator::EmulatorIO::end_def (
    int ncid
) 

Must be called after defining dimensions and variables, before writing data.

Parameters:

• ncid File ID

Returns:

true on success

---

function finalize

Finalize the PIO subsystem.

static void emulator::EmulatorIO::finalize () 

Should be called before MPI_Finalize to release resources.

---

function get_dim_size

Get the size of a dimension.

static int emulator::EmulatorIO::get_dim_size (
    int ncid,
    const std::string & dimname
) 

Parameters:

• ncid File ID
• dimname Dimension name

Returns:

Dimension length, or -1 if not found

---

function has_var

Check if a variable exists in the file.

static bool emulator::EmulatorIO::has_var (
    int ncid,
    const std::string & varname
) 

Parameters:

• ncid File ID
• varname Variable name

Returns:

true if variable exists

---

function initialize

Initialize the PIO subsystem.

static void emulator::EmulatorIO::initialize (
    MPI_Comm comm,
    const std::string & comp_name
) 

Must be called once before any file operations. Typically called from EmulatorComp::create_instance().

Parameters:

• comm MPI communicator for parallel I/O
• comp_name Component name (for logging)

---

function is_initialized

Check if PIO is initialized.

static inline bool emulator::EmulatorIO::is_initialized () 

Returns:

true if initialize() has been called successfully

---

function open_file

Open an existing NetCDF file for reading.

static int emulator::EmulatorIO::open_file (
    const std::string & filename
) 

Parameters:

• filename Path to the file

Returns:

NetCDF file ID (ncid), or -1 on failure

---

function read_var_1d

Read a 1D double array from a NetCDF variable.

static bool emulator::EmulatorIO::read_var_1d (
    int ncid,
    const std::string & varname,
    double * data,
    int size
) 

Parameters:

• ncid File ID
• varname Variable name
• data Output buffer (must be pre-allocated)
• size Number of elements to read

Returns:

true on success, false if variable not found or read failed

---

function read_var_1d_int

Read a 1D integer array from a NetCDF variable.

static bool emulator::EmulatorIO::read_var_1d_int (
    int ncid,
    const std::string & varname,
    int * data,
    int size
) 

Parameters:

• ncid File ID
• varname Variable name
• data Output buffer
• size Number of elements to read

Returns:

true on success

---

function read_var_2d

Read a 2D double array from a NetCDF variable.

static bool emulator::EmulatorIO::read_var_2d (
    int ncid,
    const std::string & varname,
    double * data,
    int nx,
    int ny
) 

Parameters:

• ncid File ID
• varname Variable name
• data Output buffer (must be pre-allocated, row-major)
• nx Size in x dimension
• ny Size in y dimension

Returns:

true on success

---

function read_var_3d_slice

Read a 2D slice from a 3D variable (time, lat, lon).

static bool emulator::EmulatorIO::read_var_3d_slice (
    int ncid,
    const std::string & varname,
    double * data,
    int nx,
    int ny,
    int time_idx
) 

Parameters:

• ncid File ID
• varname Variable name
• data Output buffer
• nx Size in x dimension
• ny Size in y dimension
• time_idx Time index to read

Returns:

true on success

---

function sync_file

Synchronize (flush) file contents to disk.

static void emulator::EmulatorIO::sync_file (
    int ncid
) 

Parameters:

• ncid File ID

---

function write_var_1d

Write a 1D double array to a NetCDF variable.

static bool emulator::EmulatorIO::write_var_1d (
    int ncid,
    const std::string & varname,
    const double * data,
    int size
) 

Parameters:

• ncid File ID
• varname Variable name (must already exist)
• data Input data buffer
• size Number of elements to write

Returns:

true on success

---

function write_var_2d

Write a 2D double array to a NetCDF variable.

static bool emulator::EmulatorIO::write_var_2d (
    int ncid,
    const std::string & varname,
    const double * data,
    int nx,
    int ny
) 

Parameters:

• ncid File ID
• varname Variable name (must already exist)
• data Input data buffer (row-major)
• nx Size in x dimension
• ny Size in y dimension

Returns:

true on success

---

---

The documentation for this class was generated from the following file components/emulator_comps/common/src/emulator_io.hpp