Main Content


Copy attribute to new location




netcdf.copyAtt(ncid_in,varid_in,attname,ncid_out,varid_out) copies an attribute from one variable to another, possibly across files. ncid_in and ncid_out are netCDF file identifiers returned by netcdf.create or varid_in identifies the variable with an attribute that you want to copy. varid_out identifies the variable to which you want to associate a copy of the attribute.

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


This example makes a copy of the attribute associated with the first variable in the netCDF example file,, in a new file. To run this example, you must have write permission in your current directory.

% Open example file.
ncid ='','NC_NOWRITE');

% Get identifier for a variable in the file.
varid = netcdf.inqVarID(ncid,'avagadros_number');

% Create new netCDF file.
ncid2 = netcdf.create('','NC_NOCLOBBER');

% Define a dimension in the new file.
dimid2 = netcdf.defDim(ncid2,'x',50);

% Define a variable in the new file.
varid2 = netcdf.defVar(ncid2,'myvar','double',dimid2);

% Copy the attribute named 'description' into the new file,
% associating the attribute with the new variable.
% Check the name of the attribute in new file.
attname = netcdf.inqAttName(ncid2,varid2,0)

attname =