NumPy’s array dimension

To determine dimension of an NumPy (np) array simply check length of its shape

>>> r = np.random.random((4,2,512,2,256))
>>> r.shape
(4, 2, 512, 2, 256)
>>> Dimension = len(r.shape)
>>> Dimension
5
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Pythons ‘if’ conditions

The ‘if’ condition, being frequently used as it is, is not always well understood. Most of the people don’t care about the order of referenced conditions, which is fine. However, wanting to get most of it, one should consider putting the less compute demanding conditions first. Here is an example in Python:

>>> def one():
...   print '1'
...   return True
... 
>>> def two():
...   print '2'
...   return False
... 
>>> one() and two()
1
2
False
>>> two() and one()
2
False

As you can see, having two conditions linked with ‘and’, they are checked one at the time starting from left most. It is not magic. This is exactly what one would expect. If ‘if’ statement is able to make a decision during the evaluation, it will!