title: laply to access a single value
body: <p>I have a list of data.frames and would like to construct a new data.frame from the list like so:</p>
  
  <pre><code> u=runif(2, 0, 1)
   u.obs=list(data.frame(site='dl',  
                         swe.obs=runif(4, 0, 1),
                         model.type='r'),
              data.frame(site='nt', 
                         swe.obs=runif(5, 0, 1),
                         model.type='lm'),
              data.frame(site='nt',
                         swe.obs=runif(3,0,1),
                         model.type='lm'),
              data.frame(site='nt',
                         swe.obs=runif(3,0,1),
                         model.type='r'))
  </code></pre>
  
  <p>EDIT: @dickoa gave an answer that worked for my example but not for real so I am adding to u.obs to make it more real.</p>
  
  <p>EDIT2: Just kidding. it looked different, but is the same from what I can tell.</p>
  
  <pre><code>summ.df=data.frame(model=u,
                     obs.min=laply(u.obs$swe.obs, min), 
                     obs.max=laply(u.obs$swe.obs, max), 
                     obs.mean=laply(u.obs$swe.obs, mean),
                     site=laply(u.obs$site, '[', 1),
                     model.type=laply(u.obs$model.type, '[', 1), 
                     date=laply(u.obs$date, '[', 1))
  </code></pre>
  
  <p>but I can't extrct <code>site</code> and <code>model.type</code> even though <code>u.obs[[1]]$site[1]</code> works fine. Can someone assist me?
  Thanks</p>