title: How to copy data from a numpy array to another
body: <p>What is the fastest way to copy data from array b to array a, without modifying the address of array a. I need this because an external library (PyFFTW) uses a pointer to my array that cannot change.</p>
  
  <p>For example:</p>
  
  <pre><code>a = numpy.empty(n, dtype=complex)
  for i in xrange(a.size):
    a[i] = b[i]
  </code></pre>
  
  <p>It is possible to do it without a loop?</p>