title: numpy structured array from arbitrary-level nested dictionary
body: <p>I have an arbitrary-level nested dictionary that contains field names as keys, and 1-D numpy arrays of the same size as values, e.g.:</p>
  
  <pre><code>d = {'a' : arr1, 'b' : {'b1' : arr2, 'b2' : {'c' : arr3}}}
  </code></pre>
  
  <p>Is there a simple way to build a numpy structured array from it that reflects the original hierarchy? Also, would be good to preserve field name ordering if <code>OrderedDict</code> is given. The usual <code>np.array</code>, <code>np.asarray</code>, <code>np.rec.array</code> functions do not seem to help.</p>