The where function in numpy

[saund1pe]

Hello,

This isn't necessarily a homework problem or even about a class that I'm taking. I'm trying to teach myself python for graduate level work and I'm using a book to try and teach myself. I came across code in the book and I'm a little confused about. The code is as follows:

import Numpy as N
a = N.reshape(N.arange(8), (2,2,2) )
condition = N.logical_and(a>3, a<6)
answer_indices = N.where(condition)
answer = (a*2)[answer_indices]

Now, what I'm confused about is when you print answer_indices it comes out as:

Output:
(array([1, 1]), array([0, 0]), array([0,1]))

and I'm not entirely sure why that is. I may be a little confused with 3-D arrays in general so could somebody explain to me why this comes out this way?

Thanks.