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rlatexknitrsweave

How to write an if-then statement in LaTeX using the value of an R variable in knitr/Sweave

I am currently using knitr along with R 3.0.2 and RStudio in order to produce a LaTeX report. My report is typed up as a .Rnw file, and compiled using the knit2pdf function.

I would like to use an if-then formulation in LaTeX in order to create a separate section, but have the if-then condition use the value of a variable from R (let's call it CreateOptionalSection).

Is this possible? If so, how can I refer to the R variable in the .tex document?

Solution

  • Add \usepackage{comment} to the preamble of your latex file.

    At the line before the optional section starts, do

    <<startcomment, results='asis', echo=FALSE>>=
if(!CreateOptionalSection){
  cat("\\begin{comment}")
}
@

    At the line after the optional section ends, do

    <<endcomment, results='asis', echo=FALSE>>=
if(!CreateOptionalSection){
  cat("\\end{comment}")
}
@