title: Subset elements in a list based on a logical condition
body: <p>How can I subset a list based on a condition (TRUE, FALSE) in another list? Please, see my example below:</p>
  
  <pre><code>l &lt;- list(a=c(1,2,3), b=c(4,5,6,5), c=c(3,4,5,6))
  l
  $a
  [1] 1 2 3
  
  $b
  [1] 4 5 6 5
  
  $c
  [1] 3 4 5 6
  
  cond &lt;- lapply(l, function(x) length(x) &gt; 3)
  cond
  $a
  [1] FALSE
  
  $b
  [1] TRUE
  
  $c
  [1] TRUE
  
  &gt; l[cond]
  </code></pre>
  
  <blockquote>
    <p>Error in l[cond] : invalid subscript type 'list'</p>
  </blockquote>