How can I add a subtitle and change the font size of ggplot plots in R?

Question

I tried adding a subtitle using +opts(subtitle="text") but nothing showed up. The main title does work (+opts(title="text")).

I would also like to use a larger font for the axis (labels and coordinates), but I can't tell how to do that.

Answer 1

theme_get() will show you the "hidden" options that you can use in opts()

Specifically:

opts(axis.text.x=theme_text(size=X)
opts(axis.text.y=theme_text(size=X)

Change size, to your desired size.

wrt the title, you can use "\n" to move the remaining text to a new line:

opts(title="text \n more text") 

ggplot2 doesn't have "subtitle" functionality. But you can use the \n term in any of the labels to drop down a line.