title: Adding a column to data.frame and fill that column with a particular string using R
body: <p>The data frame looks like </p>
  
  <pre><code>y1 x2 x3 x4 x5
  2  3  5   2  5
  11 13 34  4  4
  21 3  45  55 89
  </code></pre>
  
  <p>The study requires to add another column named x1 to this data.frame named x2 and fill all the observations with a particular string z. The output should look like :</p>
  
  <pre><code>y1 x1 x2 x3 x4 x5
  2  z  3  5   2  5
  11 z 13 34  4  4
  21 z 3  45  55 89
  </code></pre>
  
  <p>Kindly help as I tried searching it on this forum but unable to find it.</p>