Is it possible, with Python + netCDF4, to open an existing NetCDF file and change one of the dimensions from fixed size to an unlimited dimension, such that I can append data to it? I found this question/answer, which lists several options for doing this with NCO/xarray, but I'm specifically looking for a method using the netCDF4 package. Below is a minimal example which creates a NetCDF file with a fixed dimension (this part, of course, does not exist in reality, otherwise I could simply create the file with an unlimited dimension...), and then re-opens it in an attempt to modify the time dimension. The netCDF4.Dimension time_dim has a function/method isunlimited() to test whether the dimension is unlimited or not, but nothing like e.g. make_unlimited(), which I was hoping for. import netCDF4 as nc4 import numpy as np # Create dataset for testing nc1 = nc4.Dataset('test.nc', 'w') dim = nc1.createDimension('time', 10) var = nc1.createVariable('time', 'f8', 'time') var[:] = np.arange(10) nc1.close() # Read it back nc2 = nc4.Dataset('test.nc', 'a') time_dim = nc2.dimensions['time'] # ... # (1) Make time_dim unlimited # (2) Append some data # ... nc2.close() Continue reading...
