title: show range in a log scale
body: <p>I'd like to include the range of possible values for <code>y_val</code> where the upper and lower bands are available. I tried using <code>geom_errorbar</code> which works for the continuous scale but not in log scale. How can I fix this?</p>
  <pre><code>x_val &lt;- c(2, 3, 6, 12, 24)
  y_val&lt;-c(1,3,15,25,30) 
  y_upper&lt;- c(1.2,3.2, 16, 28,40)
  y_lower &lt;-c(0.8,2.9, 12, 22,25)
  
  df &lt;- data.frame(x_val=x_val,y_val=y_val,y_upper=y_upper,
                   y_lower=y_lower)
  
  ggplot(data=df,aes(x=x_val,y=y_val))+
    geom_line()+
    geom_point()+
    geom_errorbar(ymin = y_lower, ymax = y_upper)+
    scale_y_log10()+
    scale_x_log10()
  </code></pre>