r - Putting mathematical symbols and subscripts mixed with regular letters

Question

This question already has answers here: question from:https://stackoverflow.com/questions/65851159/long-mathematical-unit-on-y-axis-ggplt2

Answer 1

Something like this :

g <- ggplot(data=data.frame(x=0,y=0))+geom_point(aes(x=x,y=y))
g+ xlab( expression(paste("Value is ", sigma,",", R^{2},'=0.6')))

EDIT

Another option is to use annotate with parse=T:

g+ annotate('text', x = 0, y = 0, 
        label = "Value~is~sigma~R^{2}==0.6 ",parse = TRUE,size=20) 

EDIT

The paste solution may be useful if the constant 0.6 is computed during plotting.

r2.value <- 0.90
g+ xlab( expression(paste("Value is ", sigma,",", R^{2},'=',r2.value)))