def test_scharr_zeros():
 result = filters.scharr(np.zeros((10, 10)), np.ones((10, 10), bool))
 assert np.all((result < 1e-16))

def test_scharr_zeros ( ) : result = filters . scharr ( np . zeros ( ( 10 , 10 ) ) , np . ones ( ( 10 , 10 ) , bool ) ) assert np . all ( ( result < 1e-16 ) )
scharr on an array of all zeros .