title: How do I concatenate two one-dimensional arrays in NumPy?
body: <p>I have two arrays <code>A = [a1, ..., an]</code> and <code>B = [b1, ..., bn]</code>.
  I want to get new matrix C that is equal to </p>
  
  <pre><code>[[a1, b1],
   [a2, b2],
   ...
   [an, bn]]
  </code></pre>
  
  <p>How can I do it using <code>numpy.concatenate</code>?</p>