title: R's strptime of a time datetime at midnight (00:00:00) gives NA
body: <p>R's base <code>strptime</code> function is giving me output I do not expect.</p>
  
  <p>This works as expected:</p>
  
  <pre><code>strptime(20130203235959, "%Y%m%d%H%M%S")
  # yields "2013-02-03 23:59:59"
  </code></pre>
  
  <p>This too:</p>
  
  <pre><code>strptime(20130202240000, "%Y%m%d%H%M%S")
  # yields "2013-02-03"
  </code></pre>
  
  <p><strong>...but this does not. Why?</strong></p>
  
  <pre><code>strptime(20130203000000, "%Y%m%d%H%M%S")
  # yields NA
  </code></pre>
  
  <p><strong>UPDATE</strong></p>
  
  <p>The value <code>20130204000000</code> showed up in a log I generated on a Mac 10.7.5 system using the command:</p>
  
  <pre class="lang-bsh prettyprint-override"><code>➜  ~  echo `date +"%Y%m%d%H%M%S"`
  20130204000000
  </code></pre>
  
  <p><strong>UPDATE 2</strong></p>
  
  <p>I even tried <a href="http://cran.r-project.org/web/packages/lubridate/" rel="nofollow">lubridate</a>, which seem to be the recommendation:</p>
  
  <pre><code>&gt; parse_date_time(c(20130205000001), c("%Y%m%d%H%M%S"))
   1 parsed with %Y%m%d%H%M%S
  [1] "2013-02-05 00:00:01 UTC"
  &gt; parse_date_time(c(20130205000000), c("%Y%m%d%H%M%S"))
  1 failed to parse.
  [1] NA
  </code></pre>
  
  <p>...and then funnily enough, it printed out "00:00:00" when I added enough seconds to <code>now()</code> to reach midnight:</p>
  
  <pre><code>&gt; now() + new_duration(13000)
  [1] "2013-02-10 00:00:00 GMT"
  </code></pre>