netCDF 4.2.1.1
|
The ncgen3 tool is the new name for the older, original ncgen utility.
The ncgen3 tool generates a netCDF file or a C or FORTRAN program that creates a netCDF dataset. If no options are specified in invoking ncgen3, the program merely checks the syntax of the CDL input, producing error messages for any violations of CDL syntax.
The ncgen3 utility can only generate classic-model netCDF-4 files or programs.
UNIX syntax for invoking ncgen3:
ncgen3 [-b] [-o netcdf-file] [-c] [-f] [-v2|-v3] [-x] [input-file]
where:
-b Create a (binary) netCDF file. If the '-o' option is absent, a default file name will be constructed from the netCDF name (specified after the netcdf keyword in the input) by appending the '.nc' extension. Warning: if a file already exists with the specified name it will be overwritten.
-o netcdf-file Name for the netCDF file created. If this option is specified, it implies the '-b' option. (This option is necessary because netCDF files are direct-access files created with seek calls, and hence cannot be written to standard output.)
-c Generate C source code that will create a netCDF dataset matching the netCDF specification. The C source code is written to standard output. This is only useful for relatively small CDL files, since all the data is included in variable initializations in the generated program.
-f Generate FORTRAN source code that will create a netCDF dataset matching the netCDF specification. The FORTRAN source code is written to standard output. This is only useful for relatively small CDL files, since all the data is included in variable initializations in the generated program.
-v2 The generated netCDF file or program will use the version of the format with 64-bit offsets, to allow for the creation of very large files. These files are not as portable as classic format netCDF files, because they require version 3.6.0 or later of the netCDF library.
-v3 The generated netCDF file will be in netCDF-4/HDF5 format. These files are not as portable as classic format netCDF files, because they require version 4.0 or later of the netCDF library.
-x Use “no fill” mode, omitting the initialization of variable values with fill values. This can make the creation of large files much faster, but it will also eliminate the possibility of detecting the inadvertent reading of values that haven't been written.