title: Specify correct dtypes to pandas.read_csv for datetimes and booleans
body: <p>I am loading a csv file into a Pandas DataFrame. For each column, how do I specify what type of data it contains using the <code>dtype</code> argument?</p>
  
  <ul>
  <li>I can do it with <strong>numeric</strong> data (code at bottom)...</li>
  <li>But how do I specify <strong>time</strong> data...</li>
  <li>and <strong>categorical</strong> data such as factors or booleans? I have tried <code>np.bool_</code> and <code>pd.tslib.Timestamp</code> without luck.</li>
  </ul>
  
  <p>Code:</p>
  
  <pre><code>import pandas as pd
  import numpy as np
  df = pd.read_csv(&lt;file-name&gt;, dtype={'A': np.int64, 'B': np.float64})
  </code></pre>