title: GGplot Barplot does not accept Y value?
body: <p>I have a dataframe:</p>
  
  <pre><code>&gt;picard
  count    reads
   1    20681318
   2     3206677
   3      674351
   4      319173
   5      139411
   6      117706
  </code></pre>
  
  <p>How do I plot  log10(count) vs log10(reads)  on a ggplot (barplot)?</p>
  
  <p>I tried: </p>
  
  <pre><code>ggplot(picard) + geom_bar(aes(x=log10(count),y=log10(reads)))
  </code></pre>
  
  <p>But it is not accepting y=log10(reads). How do I plot my y values?</p>