title: Understanding about the numpy.where
body: <p>I am reading the <code>numpy.where(condition[, x, y])</code> <a href="http://docs.scipy.org/doc/numpy/reference/generated/numpy.where.html" rel="nofollow">documentation</a>, but I can not understand the small example: </p>
  
  <pre><code>&gt;&gt;&gt; x = np.arange(9.).reshape(3, 3)
  &gt;&gt;&gt; np.where( x &gt; 5 )
  Out: (array([2, 2, 2]), array([0, 1, 2]))
  </code></pre>
  
  <p>Can some one explain how the result comes?</p>