title: reading columns of a tabdelimited file into variables
body: <p>Given a tab delimited file in the following format, I need to perform operations  on column-wise manner.  The easiest solution that I know is to use pandas package, however my file being couple of gigs, I am having difficulty reading it. So I decided to use normal streaming method. </p>
  
  <p>Here, I want to generate column variables dynamically (the number of columns are ~ 500), each of which will store all the values in that particular column including blanks. For ex:
  variable <code>a</code> will be a list <code>[11,22,31,,42,555]</code>.</p>
  
  <pre><code>a   b   c   d   e   f
  11      9   9   1   6
  22  8   0   8   2   
  31  7       7   3   5
      6   1   6       4
  42  6   2   5   2   3
  555     3   4   1   2
  </code></pre>
  
  <p>How can I generate these variables by reading the entire file just once?</p>