title: Select columns of data from .txt to .csv
body: <p>I am quite new to python (well more like I've only been using it for the past week).  My task seems fairly simple, yet I am struggling.  I have several large text files each with many columns of data in them from different regions.  I would like to take the data from one text file and extract only the columns of data that I need and write it into a new .csv file.  Currently they are tab delimitated but I would like the output to be comma delimitated.</p>
  
  <p>I have:</p>
  
  <pre><code>#YY  MM DD hh mm WVHT  SwH  SwP  WWH  WWP SwD WWD   MWD
  #yr  mo dy hr mn    m    m  sec    m  sec  -  degT  degT
  2010 07 16 17 00  0.5  0.5  5.0  0.3  4.0 SSE SSE   163
  2010 07 16 16 00  0.6  0.5  5.9  0.3  3.8 SSE SSE   165
  2010 07 16 15 00  0.5  0.5  6.7  0.3  3.6 SSE  SW   151
  2010 07 16 14 00  0.6  0.5  5.6  0.3  3.8 SSE SSE   153
  </code></pre>
  
  <p>I only want to keep: DD, WVHT, and MWD</p>
  
  <p>Thanks in advance,
  Harper</p>