\name{weaver}
\alias{weaver}
\alias{weaverLatexSetup}
\title{A modified R/LaTeX Driver for Sweave}
\description{
  A modified driver for \code{\link{Sweave}} that translates R code
  chunks in LaTeX files.  Presently, the primary modification is that
  this version provides chunk caching.  In the chunk options, you can
  specify \code{cache=TRUE} and the results of that chunk will be
  cached.
}
\usage{
weaver()

weaverLatexSetup(file, syntax, output = NULL, quiet = FALSE, debug = FALSE, echo = TRUE, eval = TRUE, keep.source = FALSE, split = FALSE, stylepath = TRUE, pdf = TRUE, eps = TRUE, use.cache = TRUE)
}
\arguments{
  \item{file}{Name of Sweave source file.}
  \item{syntax}{An object of class \code{SweaveSyntax}.}
  \item{output}{Name of output file, default is to remove extension
    \file{.nw}, \file{.Rnw} or \file{.Snw} and to add extension
    \file{.tex}. Any 
    directory names in \code{file} are also removed such that the output
    is created in the current working directory.}
  \item{quiet}{If \code{TRUE} all progress messages are suppressed.}
  \item{debug}{If \code{TRUE}, input and output of all code
    chunks is copied to the console.}
  \item{stylepath}{If \code{TRUE}, a hard path to the file \file{Sweave.sty}
    installed with this package is set, if \code{FALSE}, only
    \code{\\usepackage\{Sweave\}} is written. The hard path makes the
    TeX file less
    portable, but avoids the problem of installing the current
    version of \file{Sweave.sty} to some place in your TeX input path.
    The argument is ignored if a \code{\\usepackage\{Sweave\}} is
    already present in the Sweave source file.
  }
  \item{echo}{set default for option \code{echo}, see details below.}
  \item{eval}{set default for option \code{eval}, see details below.}
  \item{keep.source}{set default for option 'keep.source', see details below.}
  \item{split}{set default for option \code{split}, see details below.}
  \item{pdf}{set default for option \code{pdf}, see details below.}
  \item{eps}{set default for option \code{eps}, see details below.}
  \item{use.cache}{a logical indicating whether or not to use the
    caching system.  If \code{FALSE}, no caching is performed and all
    code chunks are recomputed.}
}
\section{Supported Options}{
  \code{weaver} supports the following options for code chunks (the values
  in parentheses show the default values):
  \describe{
    \item{echo:}{logical (\code{TRUE}). Include S code in the
      output file?}
    \item{eval:}{logical (\code{TRUE}). If \code{FALSE}, the code chunk is not
      evaluated, and hence no text or graphical output produced.}

    \item{keep.source:}{logical (\code{FALSE}).  When echoing, if \code{keep.source ==
          TRUE} the original source is copied to the file.  Otherwise,
          deparsed source is echoed.}

    \item{results:}{character string (\code{verbatim}).
      If \code{verbatim}, the output of S commands is
      included in the verbatim-like Soutput environment. If
      \code{tex}, the output is taken to be already proper latex markup
      and included as is. If \code{hide} then all output is
      completely suppressed (but the code executed during the weave).}
    \item{print:}{logical (\code{FALSE})
      If \code{TRUE}, each expression in the
      code chunk is wrapped into a \code{print()} statement before evaluation,
      such that the values of all expressions become visible.}
    \item{term:}{logical (\code{TRUE}). If \code{TRUE}, visibility of values
      emulates an interactive R session: values of assignments are not
      printed, values of single objects are printed. If \code{FALSE},
      output comes only from explicit \code{\link{print}} or
      \code{\link{cat}} statements.}
    \item{split:}{logical (\code{FALSE}). If \code{TRUE}, text output is
      written to separate files 
      for each code chunk.}
    \item{strip.white:}{character string (\code{false}). If \code{true}, blank
      lines at the beginning and end of output are removed. If
      \code{all}, then all blank lines are removed from the output.}
    \item{prefix:}{logical (\code{TRUE}). If \code{TRUE} generated filenames of
      figures and output have a common prefix.}
    \item{prefix.string:}{a character string, default is the name of the
      \file{.Snw} source file.}
    \item{include:}{logical (\code{TRUE}), indicating whether input
      statements for text output and includegraphics statements
      for figures should be auto-generated. Use \code{include = FALSE} if
      the output should appear in a different place than the code chunk
      (by placing the input line manually).}
    \item{fig:}{logical (\code{FALSE}), indicating whether the code
      chunk produces 
      graphical output. Note that only one figure per code chunk can be
      processed this way.}
    \item{eps:}{logical (\code{TRUE}), indicating whether EPS figures shall be
      generated. Ignored if \code{fig = FALSE}.} 
    \item{pdf:}{logical (\code{TRUE}), indicating whether PDF figures shall be
      generated. Ignored if \code{fig = FALSE}.}
    \item{width:}{numeric (6), width of figures in inch.}
    \item{height:}{numeric (6), height of figures in inch.}
    \item{cache}{If \code{TRUE} and \code{weave} was called with
      \code{use.cache=TRUE}, then the caclulations in the code chunk
      will be cached.  Subsequent invocations will restore from the
      cache if the code chunk has not changed.  Side effects are not
      captured.  Do not use for chunks defining S4 classes or methods.}
  }
}
\author{Seth Falcon (borrowing heavily from code by Friedrich Leisch)}
\references{
  Friedrich Leisch: Sweave User Manual, 2002\cr
  \url{http://www.ci.tuwien.ac.at/~leisch/Sweave}
}
\seealso{\code{\link{Sweave}}, \code{\link{Rtangle}}}

\examples{
\dontrun{
  Sweave("yourfile.Rnw", driver=weaver())
}
}

\keyword{utilities}