title: Difference mapply and .mapply
body: <p>I was trying to find out info about .mapply but did not find any good explanation. So could anyone explain the difference between mapply and .mapply? </p>
  
  <p>Example:
  Why does 
  <code>.mapply(cbind,mylist,NULL)</code> 
  works but not:</p>
  
  <pre><code>mapply(cbind,mylist,NULL)
  </code></pre>
  
  <p>?</p>
  
  <pre><code>    mylist=list(list(data.frame(a=3,b=2,c=4),data.frame(d=5,e=6,h=8),data.frame(k=2,e=3,b=5,m=5)),
                    list(data.frame(a=32,b=22,c=42),data.frame(d=5,e=63,h=82),data.frame(k=2,e=33,b=5,m=5)),
                    list(data.frame(a=33,b=21,k=41,c=41),data.frame(d=5,e=61,h=80),data.frame(k=22,e=3,b=5,m=5)))
  
  ?
  </code></pre>