How do I append new data to an existing variable in a NETCDF file ?

I need to append some data to an existing variable in a netcdf file (.nc file). Say, if I have created a netcdf file as follows,

% Create a 50 element vector for a variable.

   my_vardata = linspace(0,50,50);

   % Open netCDF file.

   ncid = netcdf.create('foo.nc','NC_WRITE')

   % Define the dimensions of the variable.

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

   % Define a new variable in the file.

   my_varID = netcdf.defVar(ncid,'my_var','double',dimid)

   % Leave define mode and enter data mode to write data.

   netcdf.endDef(ncid)

   % Write data to variable.

   netcdf.putVar(ncid,my_varID,my_vardata);

Now I want to open the file and append the some new data, say new_data=(51:100) to my_vardata in the file. How can I achieve this?

Answer 1

[MathWorks Support Team]

It is possible to append new data to an existing variable in a netcdf file. To make this possible, the dimension of the variable must be defined as NC_UNLIMITED. This is demonstrated using the attached MATLAB file "appendnewdata.m".