title: Select rows for a specific month in Pandas
body: <p>I have a dataframe with 12 hourly data for over 10 years. All data are stored in date wise. I would like to extract columns containing the data from a specific month (note that month is not in standard 1, 2, 3, format). The rows of the 'date' column which I have looks like this:</p>
  
  <pre><code>01-May-07
  02-May-07
  .
  .
  .
  31-Oct-17
  </code></pre>
  
  <p>How do I select only columns which contain data only for May, Jun etc.</p>
  
  <p>Initially I thought that I can extract using <code>df[df['DATE'].str.contains('May')]</code>. But it did not work as expected resulting in output as input.</p>
  
  <p>Edit 1</p>
  
  <pre><code>DATE    TIME    MOONPH  SPEED   GUST    CLOUD AMOUNT    DRY WET DEW RH
  01-May-07   230 NM7 6   0   4   27.4    25.4    25.4    86
  01-May-07   330 NM7 4   0   4   27.4    25.4    25.4    86
  01-May-07   430 NM7 3   0   4   27.4    25.4    25.4    86
  01-May-07   530 NM7 2   0   4   27.4    25.4    25.4    89
  01-May-07   630 NM7 3   0   5   27.4    26  25.4    85
  01-May-07   700 NM7 0   0   4   27.8    26  25.4    81
  01-May-07   730 NM7 0   0   4   27.8    26  25.4    81
  01-May-07   800 NM7 2   0   4   27.8    26  25.4    81
  01-May-07   830 NM7 5   0   4   29.2    26  24.6    76
  01-May-07   900 NM7 5   0   4   29.2    26  24.6    76
  01-May-07   930 NM7 5   0   2   29.8    26  24.6    76
  01-May-07   1000    NM7 5   0   4   30.8    26  24.6    76
  01-May-07   1030    NM7 5   0   4   30.8    26  24.6    76
  01-May-07   1100    NM7 6   0   4   31.4    26  24.6    68
  .
  .
  .
  01-May-17   1630    NM7 8   0   5   32.6    27.4    25.6    68
  01-May-17   1930    NM7 8   0   5   32  27.4    25.6    69
  01-May-17   430 NM7 0   0   5   27.2    25  24  83
  01-May-17   30  NM7 0   0   5   29.6    27.2    26.2    82
  01-May-17   530 NM7 0   0   5   26.6    24.4    23.4    83
  01-May-17   130 NM7 0   0   5   28  25.6    24.6    82
  01-May-17   630 NM7 0   0   5   26.8    24.4    23.3    81
  01-May-17   730 NM7 0   0   5   27.2    24.4    23.4    80
  01-May-17   330 NM7 0   0   5   27.2    25  24  83
  01-May-17   1230    NM7 10  0   5   32.8    28.2    25.2    64
  01-May-17   2330    NM7 4   0   4   30  26.4    24.9    75
  01-May-17   2230    NM7 5   0   4   30  26.8    25.5    77
  01-May-17   2130    NM7 4   0   4   30  26.8    25.5    77
  01-May-17   830 NM7 2   0   5   27.2    24.4    23.4    78
  01-May-17   930 NM7 3   0   5   31.2    27.2    25.6    72
  01-May-17   1830    NM7 8   0   5   32  27.4    25.6    69
  01-May-17   1130    NM7 6   0   5   32.8    28.2    25.2    64
  01-May-17   2030    NM7 6   0   4   32  26.8    25.4    76
  01-May-17   1330    NM7 10  0   5   33  27.6    25.4    64
  01-May-17   1430    NM7 10  0   5   33  27.6    25.2    65
  </code></pre>