comparing numpy arrays containing NaN

Question

For my unittest, I want to check if two arrays are identical. Reduced example:

a = np.array([1, 2, np.NaN])
b = np.array([1, 2, np.NaN])
if np.all(a==b):
          


        

Answer 1

The easiest way is use numpy.allclose() method, which allow to specify the behaviour when having nan values. Then your example will look like the following:

a = np.array([1, 2, np.nan])
b = np.array([1, 2, np.nan])

if np.allclose(a, b, equal_nan=True):
    print 'arrays are equal'

Then arrays are equal will be printed.

You can find here the related documentation