Hi Sven, Thanks for your suggestions!! This works fine for \Sexp{whatever$blabla}, but sometimes I want to show the code chunk with $ sign in some case, like a documentation or tutorial that describe function of $, I have to put a # $ as a comment after the line I use $ sign, so if sometimes I set keep.source=TRUE, the comment will show up, and it's not pretty if this workaround s used for publication. ......when I write this question, I just find another workaround, instead of putting a #$ in comment of code chunk, I put a %$ in comment of latex file, this looks wired, but it works. Thanks again!! Tengfei On Mon, Sep 13, 2010 at 1:14 PM, Sven Hartenstein wrote: > Dear Tengfei, > > > In a R code chunk, when I use data frame 's $ accessor to subset it, > > I have to put another $ in the comment, or the latex will treated as > > math mode? > > This has been discussed before. See this thread: > https://stat.ethz.ch/pipermail/ess-help/2009-November/thread.html#5679 > > What I do is thus: > > df[df[["X_STATE"]]==6,'X_STATE'] <- 'CA' > > Best, > > Sven > > ______________________________________________ > ESS-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/ess-help > -- Tengfei Yin MCDB PhD student 1620 Howe Hall, 2274, Iowa State University Ames, IA,50011-2274 Homepage: www.tengfei.name [[alternative HTML version deleted]]