title: Would POSIXct or Lubridate work on this?
body: <p>I got a date from <code>searchTwitter</code> function from TwitteR package, and I have a very hard time of converting it to MM/DD/YYYY. I have tried <code>POSIXct</code> and <code>lubridate</code> but none is working. I would like to seek your help to show me what I did wrong.</p>
  
  <p>The date that I receive from Twitter  as follow :</p>
  
  <pre><code>[1] 1408642144 1408642135 1408642110 1408642091 1408642038 1408642036 1408642035
  </code></pre>
  
  <p>I've tried the <code>POSIXct</code> function as :</p>
  
  <pre><code>r_stats_created &lt;- sapply(r_stats,function (x) as.POSIXct(x$getCreated(),origin="1970-01-01"))
  </code></pre>
  
  <p>But nothing work, it gave me the same result as I had before :</p>
  
  <pre><code>head(r_stats_created)
  [1] 1408642144 1408642135 1408642110 1408642091 1408642038 1408642036 1408642035
  </code></pre>
  
  <p>It did not convert to MM/DD/YYYY as I wish. So please help me to show me what I did wrong.</p>