Use a variable within a plotmath expression

Question

I\'m trying to place the results of a regression (i.e., R2) in a graph, but can\'t seem to figure out how to call a variable from within an expression (it pastes the variabl

Answer 1

I've managed to put it together using the substitute function.

R2Val <- signif(summary(sMod_pre90)$r.squared[1], 2)
text(92, 4, substitute(R^2 ~ "=" ~ R2Val), adj = 0, cex = 0.85)

All is good.