title: Strange missing value message from geom_point
body: <p>I have a really strange missing values message which is not reproducible and I also can't find the problem. Once I get the warning, once not, and by counting NAs, I don't find it.</p>
  
  <pre><code>&gt; ggplot(jnk, aes(x=Experiment, y=Log2Intensity)) + 
  +     geom_boxplot(outlier.shape = NA) +
  +     geom_point(aes(color=imputed), 
  +                position=position_jitter(width=.4), 
  +                alpha=.5) + #scatter dots, fill if imputed
  +     scale_color_manual('Imputed', values = c(`TRUE`='blue', `FALSE`='orange')) +
  +     scale_y_continuous(limits=range_intensities) +
  +     facet_wrap(~ my_label, ncol = 10, nrow=5)
  &gt; ggplot(jnk, aes(x=Experiment, y=Log2Intensity)) + 
  +     geom_boxplot(outlier.shape = NA) +
  +     geom_point(aes(color=imputed), 
  +                position=position_jitter(width=.4), 
  +                alpha=.5) + #scatter dots, fill if imputed
  +     scale_color_manual('Imputed', values = c(`TRUE`='blue', `FALSE`='orange')) +
  +     scale_y_continuous(limits=range_intensities) +
  +     facet_wrap(~ my_label, ncol = 10, nrow=5)
  Warning message:
  Removed 1 rows containing missing values (geom_point). 
  &gt; apply(jnk, 2, function(x) sum(is.na(x)))
       my_label   Protein.IDs    Experiment     replicate       imputed Log2Intensity          page 
              0             0             0             0             0             0             0 
  </code></pre>
  
  <h2>Edit</h2>
  
  <p>As I said, it isn't reproducible. Thanks to comments from markus I figured out, that my <code>range_intensities</code> hits exactly the maximum value of <code>jnk$Log2intensity</code> and this somehow produces this error, but not always. 
  I have no idea what the problem with the arithmetic here is.</p>
  
  <p>So just to demonstrate this was not a nonsense question:</p>
  
  <pre><code>&gt; range_intensities[2] &gt;= max(jnk$Log2Intensity)
  [1] TRUE
  &gt; range_intensities[1] &lt;= max(jnk$Log2Intensity)
  [1] TRUE
  &gt; range_intensities[2] == max(jnk$Log2Intensity)
  [1] TRUE
  </code></pre>
  
  <p>I wouldn't expect any warning.</p>