pythonnumpynetcdfnetcdf4

Export NumPy array as NetCDF4 file

I'm trying to export a simple 2D NumPy array as a .nc (NetCDF) file. I'm trying to follow this example without exit.

import numpy as np
import netCDF4 as nc

# Array example
x = np.random.random((16,16))

# Create NetCDF4 dataset
with nc.Dataset('data/2d_array.nc', 'w', 'NETCDF4') as ncfile:
    ncfile.createDimension('rows', x.shape[0])
    ncfile.createDimension('cols', x.shape[1])
    data_var = ncfile.createVariable('data', 'int32', ('rows', 'cols'))
    data_var = x

However, where I import the array again is all zero:

# Read file
with nc.Dataset('data/2d_array.nc', 'r') as ncfile:
    array = ncfile.variables['data'][:]

What I'm doing wrong?

Solution

  • You're rebinding the data_var to refer to the numpy array rather than setting the data of the variable you created. Try:

    data_var[:] = x

    instead.