title: ggplot: coordinate axes are unordered when using geom_point()
body: <p>I want to create a scatter plot, but the scale of the axes is messed up. I want it to have an increasing order, but in the plot y = 7 lies between y = 8.8 and y = 11.8.</p>
  
  <p>It is a bit difficult to explain, so I uploaded a picture of the plot to </p>
  
  <p><img src="https://i.stack.imgur.com/Lu6D0.png" alt="enter image description here"></p>
  
  <pre><code>splot &lt;- ggplot(df, aes(x_val, y_val)) + geom_point() + ggtitle(title) + xlab(label) + ylab(label)
  
  df looks like that
  
               x_val            y_val            x_min            x_max            y_min            y_max series
  1        8.2640626        7.1605616 7.43370308695577 9.09442211304423 5.62731954407747 8.69380365592253   1IWG
  2       10.0321728        8.8790822 8.43774194466477 11.6266036553352 6.97682936735609 10.7813350326439   1J4N
  3 13.4994332665331 11.8238683366733 12.4200921869666 14.5787743460995 9.99549351881522 13.6522431545315   1KPL
  </code></pre>
  
  <p>Thanks for any help.</p>