title: How to add items into a numpy array
body: <p>I need to accomplish the following task:</p>
  
  <p>from:</p>
  
  <pre><code>a = array([[1,3,4],[1,2,3]...[1,2,1]])
  </code></pre>
  
  <p>(add one element to each row) to:</p>
  
  <pre><code>a = array([[1,3,4,x],[1,2,3,x]...[1,2,1,x]])
  </code></pre>
  
  <p>I have tried doing stuff like a[n] = array([1,3,4,x])</p>
  
  <p>but numpy complained of shape mismatch. I tried iterating through <code>a</code> and appending element x to each item, but the changes are not reflected.</p>
  
  <p>Any ideas on how I can accomplish this?</p>