title: Python pandas insert long integer
body: <p>I'm trying to insert long integers in a Pandas Dataframe </p>
  
  <pre><code>import numpy as np
  from pandas import DataFrame
  
  data_scores = [(6311132704823138710, 273), (2685045978526272070, 23), (8921811264899370420, 45), (17019687244989530680L, 270), (9930107427299601010L, 273)]
  dtype = [('uid', 'u8'), ('score', 'u8')]
  data = np.zeros((len(data_scores),),dtype=dtype)
  data[:] = data_scores
  df_crawls = DataFrame(data)
  print df_crawls.head()
  </code></pre>
  
  <p>But when I look in the dataframe, last values which are long are now negative :</p>
  
  <pre>
                         uid  score
  0  6311132704823138710    273
  1  2685045978526272070     23
  2  8921811264899370420     45
  3 -1427056828720020936    270
  4 -8516636646409950606    273
  </pre>
  
  <p>uids are 64 bits unsigned int, so 'u8' should be the correct dtype ? Any ideas ?</p>