What are the differences between numpy arrays and matrices? Which one should I use?

Question

What are the advantages and disadvantages of each?

From what I\'ve seen, either one can work as a replacement for the other if need be, so should I bother using both

Answer 1

As others have mentioned, perhaps the main advantage of matrix was that it provided a convenient notation for matrix multiplication.

However, in Python 3.5 there is finally a dedicated infix operator for matrix multiplication: @.

With recent NumPy versions, it can be used with ndarrays:

A = numpy.ones((1, 3))
B = numpy.ones((3, 3))
A @ B

So nowadays, even more, when in doubt, you should stick to ndarray.