title: Mean and Standard Deviation in a CSV file
body: <p>I have different csv file in a folder and I want to calculate the mean and the standard deviation of H2S and CO2 values (the thrid and fourth columns). Here's my example file:</p>
  
  <p>Time SO2 H2S CO2 Rh Tair Pressure VBatt</p>
  
  <pre><code>27/03/17 02:02 -0.06295014 124.748.880.993.867 5.278.368 8.715.702 1.570.249 862.8 1.382.667
  27/03/17 02:02 -0.07086754 12.474.390.019.852 4.843.832 8.717.385 15.703 862.8 137.486
  27/03/17 02:02 -0.07969666 12.473.647.121.563 4.773.366 8.718.224 1.570.264 862.8 1.376.822 ...
  </code></pre>
  
  <p>I've tried to write this script but I can't go ahead:</p>
  
  <pre><code>for csvfile in glob('/Users/silviamassaro/concentrazioni_gas/CS/*.csv'):
      #print(csvfile)
      with open(csvfile, 'r') as f: 
          r = csv.reader(f)
          for row_index, row in enumerate(r): 
              for col_index, data in enumerate(row):
                  print(row_index, col_index, data)
  </code></pre>
  
  <p>Could you help me?</p>