Hi,

I just came across this unexpected behaviour when creating

a np.array() from two other np.arrays of different shape.

Have a look at this example:

----

import numpy as np

a = np.zeros(3)

b = np.zeros((2,3))

c = np.zeros((3,2))

ab = np.array([a, b])

print ab.shape, ab.dtype

ac = np.array([a, c], dtype=np.object)

print ac.shape, ac.dtype

ac_no_dtype = np.array([a, c])

print ac_no_dtype.shape, ac_no_dtype.dtype

----

The output, with NumPy v1.6.1 (Ubuntu 12.04) is:

----

(2,) object

(2, 3) object

Traceback (most recent call last):

File "/tmp/numpy_bug.py", line 9, in <module>

ac_no_dtype = np.array([a, c])

ValueError: setting an array element with a sequence.

----

The result for 'ab' is what I expect. The one for 'ac' is

a bit surprising. The one for ac_no_dtype even

is more surprising.

Is this an expected behaviour?

Best,

Emanuele

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