title: from list of strings into list of floats
body: <p>I have a text file (data.txt) delimited by tab as follows:</p>
  
  <pre><code>name    height  weight
  A   15.5    55.7
  B   18.9    51.6
  C   17.4    67.3
  D   11.4    34.5
  E   23.4    92.1
  </code></pre>
  
  <p>The program below gives the result as the list of strings.</p>
  
  <pre><code>with open('data.txt', 'r') as f:
      col1 = [line.split()[0] for line in f]
      data1 = col1 [1:]
      print (data1)
  with open('data.txt', 'r') as f:
      col2 = [line.split()[1] for line in f]
      data2 = col2 [1:]
      print (data2)
  with open('data.txt', 'r') as f: 
      col3 = [line.split()[2] for line in f]
      data3 = col3 [1:]
      print (data3)
  </code></pre>
  
  <p>The results are as follows:</p>
  
  <pre><code>['A', 'B', 'C', 'D', 'E']
  ['15.5', '18.9', '17.4', '11.4', '23.4']
  ['55.7', '51.6', '67.3', '34.5', '92.1']
  </code></pre>
  
  <p>But, I want to get data2 and data3 as the list of floats.
  How can I correct above program?
  Any help, please.</p>