title: R Interactively identify points from same dataset between multiple plots
body: <p>I have an R dataframe and some scatterplots and barplots created from them.</p>
  
  <pre><code>df &lt;- data.frame(var1 = c(2,3,8,2,5,6,2,7,4,4),var2 = runif(n = 10),var3 = runif(n=10,min = 10,max=50),var4 = c(rep("A",5),rep("B",5)))
  plot(df$var1,df$var2)
  plot(df$var2,df$var3)
  barplot(df$var3,names.arg=df$var4)
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/cePSy.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/cePSy.jpg" alt="enter image description here"></a></p>
  
  <p>If I am interested in a point on the first plot, I would like to identify that point on the second, third or multiple other plots. I would like to be able to do this interactively (for example using mouse-over hover effects) in a shareable rmarkdown document.</p>
  
  <p>How can one go about doing this in R either using base graphics, ggplot or even something like shiny/rCharts? Any examples/links would be appreciated. Thanks.</p>