how to slice a subset of numpy arrays
<p>Given this array:</p>

<pre><code>&gt;&gt;&gt; a
array([[ 0,  1,  2],
       [ 3,  4,  5],
       [ 6,  7,  8],
       [ 9, 10, 11]])
</code></pre>

<p>How can I select <code>[[4,5], [7,8]]</code>? <code>a[0::2, 1:;2]</code> doesn't work</p>