[R] How to use strings from a data.frame as the argument of an expression() for plot

[MrJ Man]

Thanks for your response; one more thing: Is it
possible to use a data.frame 
for the same effect, as these values are associated
with some others (I could 
of course use them separately, but merging them in a
data.frame should be 
possible in R)?

> Try this:
>
>
> e <- expression(O[3], NO, NO[2])
> opar <- par(mfrow = c(2,2))
> for(i in 1:3) plot(1, 1, type = "b", main =
bquote(.(e[[i]]) ~ Year ~
> 2005)) par(opar)
>
> Also please read the last line to every post to
r-help and particularly
> note the part about reproducible examples.   x and
y.were undefined.
>