title: Convert month year to a date in r
body: <p>I need to convert following types of strings to a date format.</p>
  
  <pre><code>Convert "Feb 2009" to 2009-02-01
  Convert "Jan 2010" to 2010-01-01
  Convert "Mar 2011" to 2011-03-01
  </code></pre>
  
  <p>I can achieve this from the following code using <code>zoo</code> package. </p>
  
  <pre><code>as.Date(as.yearmon("Feb 2009"))
  </code></pre>
  
  <p>But due to some constraints I do not want to use this way of converting. So I want to know if there is any other way in R of achieving this task?</p>