title: Partial dashed line ggplot
body: <p>I am new to R and have managed to make a multiple line figure in ggplot. Along the x axis I have 5 time points that are discrete measures. I would like the latter half of the lineplot to be dashed (see attached image), could anybody help me edit my current code to achieve this please? Any help would be greatly appreciated. Thank you in advance! </p>
  
  <p><img src="https://i.stack.imgur.com/mkAMF.png" alt="enter image description here"></p>
  
  <pre><code>ggplot(longdata, aes(x = Time, y = Strength, colour = Group)) +
    stat_summary(fun  = mean,
                 geom = "point",)+ 
    stat_summary(fun = mean,
                 geom = "line", 
                 aes(group = Group), size =1,
                 show.legend = FALSE) + 
                 geom = "errorbar",
                 width = .1, alpha = 0.3) +
    xlab("Testing Timepoint") +
    ylab("Isometric Strength (N.m)") +
    bbtheme +
    scale_colour_manual(name = "Group",
                        labels = c("Once-weekly", "Twice-weekly"),
                        values = c("red1", "navyblue")) +
    expand_limits(y = 0)
  </code></pre>