title: sed to insert characters in a specific column
body: <p>Can anyone tell me how to insert <code>chr</code> to every character in the first column.</p>
  
  <p><strong>file in</strong></p>
  
  <pre><code>1 34566 34765    
  2 45678 45789
  3 34567 34799
  X 67895 66900
  Y 34567 34890
  </code></pre>
  
  <p><strong>file out</strong></p>
  
  <pre><code>chr1 34566 34765
  chr2 45678 45789
  chr3 34567 34799
  chrX 67895 66900
  chrY 34567 34890
  </code></pre>
  
  <p>I can't figure out how to make <code>sed -i</code> apply to a specific column. I'm not good with the syntax so if you could break down your explanation I would be grateful. Also, would it be better to use awk for this?</p>