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Put open netCDF file into define mode




netcdf.reDef(ncid) puts an open netCDF file into define mode so that dimensions, variables, and attributes can be added or renamed. Attributes can also be deleted in define mode. ncid is a valid NetCDF file ID, returned from a previous call to or netcdf.create.

This function corresponds to the nc_redef function in the netCDF library C API. To use this function, you should be familiar with the netCDF programming paradigm.


This example opens a local copy of the example netCDF file included with MATLAB®,

% Open a netCDF file.
ncid ='','NC_WRITE')

% Try to define a dimension. 
dimid = netcdf.defdim(ncid, 'lat', 50); % should fail.
??? Error using ==> netcdflib
NetCDF: Operation not allowed in data mode

Error in ==> defDim at 22
dimid = netcdflib('def_dim', ncid,dimname,dimlen);
% Put file in define mode.

% Try to define a dimension again. Should succeed.
dimid = netcdf.defDim(ncid, 'lat', 50);