[R] Sub- or superscript in factorial variable - possible?

mcg
Sun, 16 Sep 2012 02:15:03 -0000

Hello R-users,

I would like to use subscript in chemical formulas for the different
treatments in a boxplot.
Fot title, xlab and ylab sub- and superscript is no problem, but for the
different treatments of the following example I cannot get subscript.

Example:
weight <-  c(6,5,7,2,7,3,9,4,2,7,8,9,2,3,4,5)
treatments <- as.factor(rep(c('Control',
'P2O5','K2SO4','CaSO4'),4))
data <- data.frame(treatments,weight)
boxplot(data$weight~data$treatments)

If I apply expression(P[2]...) I get  "unimplemented type
'expression'
in 'HashTableSetup' ".
If there is a solution for this in base graphics or ggplot please let me
know.

Thanks in advance,
Michael