Creating views and copies

It is important to know when we are dealing with a shared array view, and when we have a copy of the array data. A slice, for instance, will create a view. This means that if you assign the slice to a variable and then change the underlying array, the value of this variable will change. We will create an array from the famous Lena image, copy the array, create a view, and, at the end, modify the view.

Getting ready

The prerequisites are the same as in the previous recipe.

How to do it...

Let's create a copy and views of the Lena array:

1. Create a copy of the Lena array:

   acopy = lena.copy()

2. Create a view of the array:

   aview = lena.view()

3. Set all the values of the view to 0 with a flat iterator:

   aview.flat = 0

The end result is that only one of the images shows the Playboy model. The other ones get censored completely:

The following is the code of this tutorial showing the behavior of array views and copies:

import scipy.misc
import matplotlib.pyplot

lena = scipy.misc.lena()
acopy...