title: How to concatenate an empty array with Numpy.concatenate?
body: <p>I need to create an array of a specific size <code>mxn</code> filled with empty values so that when I <code>concatenate</code> to that array the initial values will be overwritten with the added values.</p>
  
  <p>My current code:</p>
  
  <pre><code>a = numpy.empty([2,2])  # Make empty 2x2 matrix
  b = numpy.array([[1,2],[3,4]])    # Make example 2x2 matrix
  myArray = numpy.concatenate((a,b))    # Combine empty and example arrays
  </code></pre>
  
  <p>Unfortunately, I end up making a <code>4x2</code> matrix instead of a <code>2x2</code> matrix with the values of b.</p>
  
  <p>Is there anyway to make an actually empty array of a certain size so when I concatenate to it, the values of it become my added values instead of the default + added values?</p>