Question

What is the most efficient way of saving a numpy masked array? Unfortunately numpy.save doesn’t work:

import numpy as np
a = np.ma.zeros((500, 500))
np.save('test', a)

This gives a:

NotImplementedError: Not implemented yet, sorry...

One way seems to be using pickle, but that unfortunately is not very efficient (huge file sizes), and not platform-independent. Also, netcdf4 seems to work, but it has a large overhead just to save a simple array.

Anyone has had this problem before? I’m tempted just to do numpy.save of array.data and another for the mask.

Answer 1

import numpy as np
a = np.ma.zeros((500, 500))
a.dump('test')

then read it with

a = np.load('test')