title: Minor ticks on log10 scale using ggplot2
body: <p>I have a dataframe of ~108m rows of data, in 7 columns. I use this R script to make a boxplot of it:</p>
  
  <pre><code>ggplot(expanded_results, aes(factor(hour), dynamic_nox)) +
    geom_boxplot(fill="#6699FF", outlier.size = 0.5, lwd=.1) +
    scale_y_log10() +
    stat_summary(fun.y=mean, geom="line", aes(group=1, colour="red")) +
    ylab(expression(Exposure~to~NO[x])) + 
    xlab(expression(Hour~of~the~day)) +
    ggtitle("Hourly exposure to NOx") +
    theme(axis.text=element_text(size=12, colour="black"),
          axis.title=element_text(size=12, colour="black"),
          plot.title=element_text(size=12, colour="black"),
          legend.position="none")
  </code></pre>
  
  <p>The graph looks like this. It's pretty much fine, however it would be better to have a value towards the top of the Y axis. I guess it should be something like 1000 given the Y axis is a log10 scale. I'm not sure how to do this though?</p>
  
  <p><img src="https://i.stack.imgur.com/fl6Qh.png" alt="enter image description here"></p>
  
  <p>Any ideas please?</p>
  
  <p>EDIT: In response to DrDom:
  Try to add <code>scale_y_log10(breaks=c(0,10,100,1000))</code>. The output of doing that, is this:</p>
  
  <p><img src="https://i.stack.imgur.com/9tj44.png" alt="enter image description here"></p>
  
  <p>The output of doing the following:
  <code>scale_y_log10(breaks=c(0,10,100,1000), limits=c(0,1000))</code></p>
  
  <p>Is an error of:</p>
  
  <pre><code>Error in seq.default(dots[[1L]][[1L]], dots[[2L]][[1L]], length = dots[[3L]][[1L]]:
  'from' cannot be NA, NaN or infinite
  </code></pre>
  
  <p>In respnonse to Jaap who suggested the following code:</p>
  
  <pre><code>library(ggplot2)
  library(scales)
  
  ggplot(expanded_results, aes(factor(hour), dynamic_nox)) +
    geom_boxplot(fill="#6699FF", outlier.size = 0.5, lwd=.1) +
    stat_summary(fun.y=mean, geom="line", aes(group=1, colour="red")) +
    scale_y_continuous(breaks=c(0,10,100,1000,3000), trans="log1p") +
    labs(title="Hourly exposure to NOx", x=expression(Hour~of~the~day), y=expression(Exposure~to~NO[x])) +
    theme(axis.text=element_text(size=12, colour="black"), axis.title=element_text(size=12, colour="black"),
          plot.title=element_text(size=12, colour="black"), legend.position="none")
  </code></pre>
  
  <p>It produces this graph. Have I done something wrong? I'm still missing a '1000' tick label? A tick inbetween the 10 and the 100 would also be good given that is where most of the data is?</p>
  
  <p><img src="https://i.stack.imgur.com/qJXPL.png" alt="enter image description here"></p>