title: What is the equivalent of += (plus equals) in R
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/5738831/r-and-equivalent-from-c-c-java-etc">R:  += and ++ equivalent from c++/c#/java, etc.?</a>  </p>
  </blockquote>
  
  
  
  <p>Does R (specifically a <code>data.frame</code>) have a version of the += operator? I would like to say:</p>
  
  <pre><code>my.df[foo &gt; 50,"foo"] -= 10
  </code></pre>
  
  <p>But the best I can come up with so far is:</p>
  
  <pre><code>my.df[foo &gt; 50,"foo"] &lt;- my.df[foo &gt; 50,"foo"] - 10
  </code></pre>
  
  <p>Any help appreciated.</p>