[R] plotmath: paste string and expression [from a vector of expressions]

[Dennis Murphy]

Hi:

This seems to work:

vars2 <- c(quote(alpha), quote(beta))   # returns a list of mode call
plot(0, 0, main = bquote(bold('Foo '~.(vars2[[2]]))))

Expressions are only evaluated once, which means that inner
expressions are not evaluated. You need a call object rather than an
expression inside of bquote().

HTH,
Dennis

On Thu, Jun 2, 2011 at 11:43 AM, Marius Hofert <m_hofert at web.de> wrote:
> Dear all,
>
> I have a vector of expressions and would like to "paste" some string to it before using it in a plot:
>
> vars <- vector("expression", 2)
> vars[1] <- expression(alpha)
> vars[2] <- expression(beta)
> plot(0, 0, main=substitute(bold("Foo" ~~ VAR), list(VAR=vars[2]) ))
>
> Although I tried hard, I just can't figure out how to solve this. The title should be "Foo <theta>", where <theta> is the greek letter. I tried some constructions with bquote but that wasn't successful... I also looked in the mailing list but couldn't find anything helpful [I am sure I overlooked something].
>
> Cheers,
>
> Marius
>
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