title: How to adjust the tile height in geom tile?
body: <p>I am trying to do a plot with ggplot2, but I am struggling with the geom tile. As I am using this geom for the first time I looked closely to Hadley's documentation, but still I did not manage to get what I am after. I want to adjust both the tile width and the tile height. I found how to adjust the tile width in the documentation, but I am struggling with the height. Taking the next plot as starting point:</p>
  
  <pre><code>test &lt;- data.frame(
    x = rep(c(1,3,6),2),
    y = rep(c(1,3), each = 3),
    w = rep(c(.5,2,1), 2),
    z = sample(rep(LETTERS[1:6])))
  
  ggplot(test, aes(x=x, y=y, fill = z)) + geom_tile(aes(width = w))
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/idljP.png" alt="enter image description here"></p>
  
  <p>I would now like to adjust the height of the tiles as well. With the bottom tile in the first 'column' (at which x = 1) to run from 0 to 1, and the top tile in the first column running from 1 to 4. In the second column I want to make the bottom tile run from 0 to 3 and the top tile from 3 to 4. For the last column I want the bottom from 0 to 1.5 and the top from 1.5 to 4. I tried many things, e.g. the following:</p>
  
  <pre><code>test2 &lt;- data.frame(
   x = rep(c(1,3,6),2),
   y = c(0, 0, 0, 1, 3, 1.5),
   w = rep(c(.5,2,1), 2),
   z = sample(rep(LETTERS[1:6])),
   h = c(1, 3, 1.5, 3, 1, 2.5))
  
  ggplot(test2, aes(x=x, y=y, fill = z)) + geom_tile(aes(width = w, heigth = h))
  </code></pre>
  
  <p>but none produced the plot I was looking for.</p>
  
  <p>Any help will be greatly appreciated. Thanks in advance!</p>