title: Different y-limits on ggplot facet grid bar graph?
body: <p>My data:</p>
  
  <pre><code>    day variable      value
  1  Fri     avg1 446.521127
  2  Mon     avg1 461.676056
  3  Sat     avg1 393.366197
  4  Sun     avg1 435.985714
  5  Thu     avg1 445.571429
  6  Tue     avg1 441.549296
  7  Wed     avg1 462.042254
  8  Fri     avg2   7.442113
  9  Mon     avg2   7.694648
  10 Sat     avg2   6.556056
  11 Sun     avg2   7.266571
  12 Thu     avg2   7.426286
  13 Tue     avg2   7.359577
  14 Wed     avg2   7.700282
  </code></pre>
  
  <p>My issue is I want to create a bar graph using <code>facet_grid</code> displaying each set of avg data by day, but the observations are similar enough that I've found it helpful to specify the y-limits using <code>scale_y_continuous</code>. </p>
  
  <p>So, if I assign my ggplot to <code>g &lt;- ggplot(df, aes(x=day, y=value))</code>, I can get half of what I want by each of:</p>
  
  <pre><code>g + geom_bar(stat="identity") + facet_grid(variable~., scales="free")
  </code></pre>
  
  <p>AND</p>
  
  <pre><code>g + geom_bar(stat="identity") + scale_y_continuous(limits=c(300,500), oob=rescale_none)
  </code></pre>
  
  <p>However, I don't know how to use facet grid and then specify a scale_y_cont that will limit the size of separate y-axes. Is there a solution?</p>