title: Read file into two dimensional list
body: <p>I would like to read a file of (say 5 rows and 3 columns) into a two dimensional list.
  So, here is my code so far:</p>
  
  <p>Say my data file is:</p>
  
  <pre><code> 1.0 2.1 3.4
   1.1 2.5 3.0
   2.1 2.4 2.8
   2.6 2.5 5.6
   1.8 8.3 5.4
  
  
  
  fil = open('data.dat','r')
  
  
  data = [[]]         # initialize two-dim. list
  
  for rows in fil:
       cols = rows.split()
       data.append(cols[i] for i in cols)
  
  print(data[:][1])
  </code></pre>
  
  <p>so I expect the command <code>print(data[:][1])</code> to print all rows for column 2. That is, the output should be:</p>
  
  <pre><code>2.1
  2.5
  2.4
  2.5
  8.3
  </code></pre>
  
  <p>Any ideas and help will be highly appreciated!</p>