How can I make `bquote` replace the greek letter stored in a variable with the symbol?

Question

I want to label the axis on a plot dynamically. The labels come from a data frame and contain greek letters as well as super/sub scription.

In a static case, where I wou

Answer 1

Turn the a and b variable into symbols with rlang::sym.

library("tidyverse")

a <- "alpha"
b <- "beta"

ggplot(data.frame(x = c(1), y = c(1)), aes(x, y)) +
  geom_point() +
  labs(x = bquote(.(sym(a))[.(sym(b))])) +
  labs(y = bquote(alpha[beta]))

^{Created on 2019-11-04 by the reprex package (v0.3.0)}