[R] Sweave: Howto write real TeX formula in plot

[Jonas Stein]

Hi,

i use Sweave to put plots in my .tex Documents. (pdflatex)
Is there a nice solution for this:

a) get a real LaTeX formula in the plot area. 
I have only found very complicate solutions. Is there sth. like 
\formula{x^2 = \oint f} 

b) how can i format axis and legend to get exact the same font that is
used in the TeX-document? 

Thank you for any help. 

-- 
Jonas Stein <news at jonasstein.de>