title: Get dict from Mongo and convert to ndarray using Numpy
body: <p>I have an aggregate query in Mongo that returns data like:</p>
  
  <pre><code>{a: 1, b: 2, c: 3}
  {a: 4, b: 5, c: 6}
  {a: 7, b: 8, c: 9}
  </code></pre>
  
  <p>I would like to do an FFT for a, b and c and I need to put the data in 3 numpy arrays like this:</p>
  
  <pre><code>a = np.array([1, 4, 7])
  b = np.array([2, 5, 8])
  c = np.array([3, 6, 9])
  </code></pre>
  
  <p>What is the best option to do this using numpy as for now I am doing a for loop and it takes ages.</p>
  
  <p><strong>UPDATE:</strong></p>
  
  <p>The result from mongo is a Cursor which is iterable
  The way that I am doing it now is like this:</p>
  
  <pre><code>a = []
  b = []
  c = []
  for item in aggregation_list:
      a.append(item['a'])
      b.append(item['b'])
      c.append(item['c'])
  </code></pre>