title: GGplot add Data label to points
body: <p>How do I add data labels to points using ggplot?</p>
  
  <p>I have a stacked data frame called "stacked":</p>
  
  <pre><code> &gt; head(stacked)
      time    value variable
   1  100 152.2211       gg
   2  110 146.3304       gg
   3  115 143.5831       gg
   4  120 140.9527       gg
   5  125 138.4297       gg
   6  130 136.0057       gg
  
   &gt; tail(stacked)
        time    value variable
    755 1975 56.02922        t
    756 1980 56.14049        t
    757 1985 56.25148        t
    758 1990 56.36219        t
    759 1995 56.47262        t
    760 2000 56.58277        t
  </code></pre>
  
  <p>Now lets say I want to show data labels displaying the "value" field where the time field is equal to 100.  Here is what I have:</p>
  
  <pre><code>g&lt;- ggplot(stacked, aes( x = time,  y=value, colour=variable, group= variable) )       +   geom_line()  +
   geom_text(data = stacked[stacked$time == 100,], aes(label = stacked$value))
  print(g)
  </code></pre>
  
  <p>I am getting the error:</p>
  
  <pre><code>Error: Aesthetics must either be length one, or the same length as the dataProblems:time, value, variable, variable
  </code></pre>
  
  <p>Any ideas?</p>
  
  <p>Thank you.</p>