title: Getting only particular columns in every row in a numpy array
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/4455076/numpy-access-an-array-by-column">numpy: access an array by column</a>  </p>
  </blockquote>
  
  
  
  <p>I have a numpy array (numpy is imported as np)</p>
  
  <pre><code>gona = np.array([[ 1,  2,  3],
         [ 4,  5,  6],
         [ 7,  8,  9],
         [10, 11, 12]])
  </code></pre>
  
  <p>I can get the values of entire column of 1th row by gona[1][:]. </p>
  
  <blockquote>
    <p>array([4, 5, 6])</p>
  </blockquote>
  
  <p>But if I try to get all values of a particular column of all rows (say I want values of 1st column in every row) I would try the gona[:][1]. But the result I get from this is same as before.</p>
  
  <p>What can be the reason for this? How do I do such a thing in numpy?</p>