How do I access the ith column of a NumPy multidimensional array?

by

To access column 0:

>>> test[:, 0]
array([1, 3, 5])

To access row 0:

>>> test[0, :]
array([1, 2])

This is covered in Section 1.4 (Indexing) of the NumPy reference. This is quick, at least in my experience. It’s certainly much quicker than accessing each element in a loop.

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