How to underline text in a plot title or label? (ggplot2)

Question

Please pardon my ignorance if this is a simple question, but I can\'t seem to figure out how to underline any part of a plot title. I\'m using ggplot2.

Answer 1

Try this:

ggplot(df, aes(x = x, y = y)) + geom_point() +
  ggtitle(expression(paste("Oh how I wish for ", underline(underlining))))

Alternatively, as BondedDust points out in the comments, you can avoid the paste() call entirely, but watch out for the for:

ggplot(df, aes(x = x, y = y)) + geom_point() +
  ggtitle(expression(Oh~how~I~wish~'for'~underline(underlining)))

Or another, even shorter approach suggested by baptiste that doesn't use expression, paste(), or the many tildes:

ggplot(df, aes(x = x, y = y)) + geom_point() +
  ggtitle(~"Oh how I wish for "*underline(underlining))