title: Plot large scatterplot
body: <p>my dataset has millions of points and it is not a good idea to plot all of them. </p>
  
  <pre><code>runif(10000)-&gt;t1
  runif(10000)-&gt;t3
  as.data.frame(cbind(t1,t3))-&gt;t4
  plot(t4[,1],t4[2])
  </code></pre>
  
  <p>how can I just plot a sample of the points? I know i could sample from both col but then the problem is that the first col is the x value so I would need to get the same x and y through sampling  - or say the same indices. Not sample(t4[,1] and then sample t4[,2]</p>
  
  <p>Is there an easy way to get the 95% ranges of the values plotted into the figure as well? 
  I think a solution with predict would not work too well for me just because the dataset is large and it takes quite long to get through it. It would literally just need to be in a window of 0.1 or something the 95% value plotted on th ebottom and the top</p>