title: How can we Sum the data of .csv file columnwise using d3.js
body: <p>Given this .csv file:</p>
  
  <pre><code>date,jan,feb,march
  1-1-2011,1,2,3  
  1-2-2011,2,3,4  
  1-3-2011,1,4,5
  </code></pre>
  
  <p>and I want an array that contains value like: [4,9,12].</p>