title: Converting a dictionary to numpy matrix in python
body: <p>I am a python beginner. I have a dictionary like the following:</p>
  
  <pre><code>{'Clinton': [{'ideology': -0.5, 'vote':80}, {'ideology': -0.75, 'vote':90},
   {'ideology': -0.89, 'vote': 99}, 
  {'ideology': -0.5, 'vote':80, 'review': "She is a presidential candidate"}],
   'Alexander': [{'ideology': -0.1, 'vote':50}, {'ideology': -0.95, 'vote':20}, 
  {'ideology': -0.19, 'vote': 19}, {'ideology': -0.2, 'vote':30, 'review': "Good"}] 
  ... }
  </code></pre>
  
  <p>I want to convert this dictionary to a numpy matrix like that creating the name as one column, like:</p>
  
  <pre><code>   Name  ideology vote review
    Clinton  -0.5    80
    Clinton  -0.75   90
    Clinton  -0.89   99
    Clinton  -0.5    80   "She is a presidential candidate"
   Alexander -0.1    50
   Alexander -0.95   20
   Alexander -0.19   19
   Alexander -0.2    30   "Good"
  </code></pre>
  
  <p>How can I convert this dictionary as a numpy matrix?</p>
  
  <p>One of the problem I have is that the data has more than million observations. So looping over it will take time forever. I want to use the dictionary as a feature vector for a ridge regression.</p>