Adding greek character to axis title

Question

I want to add a greek character to the y-axis of my barplot in R.
The problem is that I need this character to be integrated in the title. I want to write:

Answer 1

And if you want to substitute variables in the text, use bquote. For instance, if you have a variable mu and want to show it in the title, then use the following idiom:

mu <- 2.8
plot(1:3, main=bquote(mu == .(mu)))

The part enclosed in .() will be substituted, so that the value of mu will be printed and not the greek "mu" character. Consult the R help on bquote for details.