title: Pulling date and time from Excel to Pandas and combining it to a timestamp
body: <p>Final Edit (hopefully):
  Oh my god you solved it! 
  After upgrading to Pandas 0.15.2, this solution seems to work:</p>
  
  <pre><code>trades['OEDatum'] = (trades[['OEDatum', 'OEUhrzeit']].apply
                           (lambda x: dt.datetime.combine
                            (x['OEDatum'].date(), x['OEUhrzeit']), axis=1))
  </code></pre>
  
  <p>Thank you very much @EDChum and @joris </p>
  
  <hr>
  
  <p>I'm trying to pull some data from an Excelsheet via read_excel into a Pandas dataframe:</p>
  
  <pre><code>        Asset    OEDatum OEUhrzeit     ODatum  OUhrzeit L/S  Entrykurs  \
  Trade                                                                    
  1      EURUSD 2014-06-12  12:00:00 2014-06-12  12:23:09   L     1.2456   
  2      USDJPY 2014-11-11  10:15:35 2014-11-11  10:34:50   S   126.6300   
  3      EURJPY 2014-12-23  13:15:24 2014-12-23  13:25:45   L   114.4600   
  4      GBPJPY 2014-12-23  14:27:36 2014-12-23  14:35:56   S   156.6000
  </code></pre>
  
  <p>the values I'm interested in, have the following data types:</p>
  
  <pre><code>OEDatum      datetime64[ns]
  OEUhrzeit            object
  ODatum       datetime64[ns]
  OUhrzeit             object
  </code></pre>
  
  <p>As you can see, Pandas pulled the dates as datetime64 values and the times are an object.</p>
  
  <p>Now I need to combine 'OEDatum' with 'OEUhrzeit' and 'ODatum' with 'OUhrzeit' to timestamps. These timestamps should later be used for searching large tickdata files.</p>
  
  <p>But it's simply not possible for me, to combine the dates with the times...</p>
  
  <p>Among a lot of other tries, I wanted to change the time data to a string and use then "to_datetime":</p>
  
  <pre><code>trades.OEUhrzeit.apply(str)
  pd.to_datetime(trades.OEUhrzeit, utc=False, format='%H%M%S')
  </code></pre>
  
  <p>but then comes this:</p>
  
  <pre><code>    Traceback (most recent call last):
    File "F:\Python Projekte\Test und Funktionsenwicklung\src\Tupel_und_ATR_Updater.py", line 251, in &lt;module&gt;
      trades_ohne_tupel()
    File "F:\Python Projekte\Test und Funktionsenwicklung\src\Tupel_und_ATR_Updater.py", line 173, in trades_ohne_tupel
      **pd.to_datetime(trades.OEUhrzeit, utc=False, format='%H%M%S')
    File "C:\Python34\lib\site-packages\pandas\tseries\tools.py", line 320, in to_datetime
      values = _convert_listlike(arg.values, False, format)**
    File "C:\Python34\lib\site-packages\pandas\tseries\tools.py", line 313, in _convert_listlike
      raise e
    File "C:\Python34\lib\site-packages\pandas\tseries\tools.py", line 287, in _convert_listlike
      arg, format, coerce=coerce
    File "tslib.pyx", line 1579, in pandas.tslib.array_strptime (pandas\tslib.c:25541)
  ValueError: time data datetime.time(12, 0) does not match format '%H%M%S'
  </code></pre>
  
  <p>So I hope someone could show me a solution for this problem.
  Thx in advance.</p>
  
  <p>EDIT: @EDChum you are right I use pandas 0.14.1, numpy 1.8.2 and Python 3.4.2
  - think that means I have to update my pandas....... </p>