[R] LaTeX in R

[Roy, Supratik]

I tried to include LaTeX expressions in the header of a plot in R.
(1) Using PlotMath, LaTeX type expressions, e.g., R^x is possible, however,
dist<-"...." (some string)
....main=expression(R^x,dist)....
does not substitute the value of dist, as well do the proper superscripting.
Also within an expression, substitute does not work, (apparently), so that 
explicit substituting of "dist" does not take place. Pasting separately,
like
 ....main=paste(expression(R^x),dist)... does not work either.
Is there any way out? Even if it is "trivial" please indicate any source of
help.

(2) Problem in (1) is stated for a general graphics device and PlotMath has
limited 
capabilities. I am aware that the "TeX" option for the graphics device is a
way out, but when converted to eps or ps, and included in a LaTeX document,
and compiled to produce pdf/ps files,
the headers are not converted into meaningful symbols. Has anyone tried
anything on this?

Many journals now have online submission procedures, which compile pdf files
on site
after the LaTeX file , and the figures, mostly required to be eps, are
uploaded. I expect
others to have come across similar problems.

Regards
Supratik.