Sweave (or other custom weave function)
  texi2dvi, and/or Stangle 
  (or other custom tangle function) on one vignette.  This is the workhorse of R CMD Sweave.
buildVignette(file, dir = ".", weave = TRUE, latex = TRUE, tangle = TRUE,  quiet = TRUE, clean = TRUE, keep = character(), engine = NULL, buildPkg = NULL, encoding, ...)NULL or character; name of vignette engine to
    use.  Overrides any \VignetteEngine{} markup in the vignette.NULL or character; an optional package in which to find
    the vignette engine.utils::Sweave), then weaves and/or tangles the vignette using
  that engine.  Finally, if clean is TRUE, newly created
  intermediate files (non targets, where these depend on the engine,
  etc, and not any in keep) will be deleted.  If clean is
  NA, and weave is true, newly created intermediate output
  files (e.g., .tex) will not be deleted even if a .pdf
  file has been produced from them.    If buildPkg is specified, it will be loaded before the vignette
  is processed, and will be used as the default package in the search
  for a vignette engine, but an explicitly specified package in the
  vignette source (e.g., using \VignetteEngine{utils::Sweave}
  to specify the Sweave engine in the utils package) will
  override it.  In contrast, if the engine argument is given, it
  will override the vignette source.
buildVignettes for building all vignettes in a package.