Multi line title in ggplot 2 with multiple italicized words

Question

I am trying to create a plot title manually formatted on two lines which includes two italicized words, I have done some s

Answer 1

As an alternative to inserting line breaks in title, you may use title together with subtitle (available from ggplot 2.2.0). Possibly this makes the plothmathing slightly more straightforward.

p <- ggplot(mtcars, aes(x = wt, y = mpg)) +
  geom_point() +
  labs(title = expression("First line: "*italic("Honorificabilitudinitatibus")),
       subtitle = expression("Second line: "*italic("Honorificabilitudinitatibus praelongus")*" and more"))
p

---

If you wish the font size to be the same on both lines, set the desired size in theme.

p + theme(plot.title = element_text(size = 12),
          plot.subtitle = element_text(size = 12))

Note that both title and subtitle are left-aligned by default in ggplot2 2.2.0. The text can be centered by adding hjust = 0.5 to element_text above.