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End netCDF file define mode




netcdf.endDef(ncid) takes a netCDF file out of define mode and into data mode. ncid is a netCDF file identifier returned by netcdf.create or

netcdf.endDef(ncid,h_minfree,v_align,v_minfree,r_align) takes a netCDF file out of define mode, specifying four additional performance tuning parameters. For example, one reason for using the performance parameters is to reserve extra space in the netCDF file header using the h_minfree parameter:

ncid = netcdf.endDef(ncid,20000,4,0,4);

This reserves 20,000 bytes in the header, which can be used later when adding attributes. This can be extremely efficient when working with very large netCDF 3 files. To understand how to use these performance tuning parameters, see the netCDF library documentation.

This function corresponds to the nc_enddef and nc__enddef functions in the netCDF library C API. To use this function, you should be familiar with the netCDF programming paradigm. See netcdf for more information.


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Take File out of Define Mode

When you create a file using netcdf.create, the functions opens the file in define mode. This example uses netcdf.endDef to take the file out of define mode.

Create a netCDF file.

ncid = netcdf.create('foo.c','NC_NOCLOBBER');

Define a dimension.

dimid = netcdf.defDim(ncid,'lat',50);

Leave define mode.


Test if still in define mode.

dimid = netcdf.defDim(ncid,'lon',50);
Error using netcdflib
The NetCDF library encountered an error during execution of 'defDim' function - 'Operation not allowed in data mode

Error in netcdf.defDim (line 25)
dimid = netcdflib('defDim', ncid,dimname,dimlen);

netcdf.defDim errors, as expected.

See Also


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