Unpacking tuples/arrays/lists as indices for Numpy Arrays

Question

I would love to be able to do

>>> A = numpy.array(((1,2),(3,4)))
>>> idx = (0,0)
>>> A[*idx]

and get

<         


        

Answer 1

Indexing an object calls:

object.__getitem__(index)

When you do A[1, 2], it's the equivalent of:

A.__getitem__((1, 2))

So when you do:

b = (1, 2)

A[1, 2] == A[b]
A[1, 2] == A[(1, 2)]

Both statements will evaluate to True.

If you happen to index with a list, it might not index the same, as [1, 2] != (1, 2)