Having trouble with pgfSweave and tikzDevice

Question

On Ben Bolker's advice I started using pgfSweave and tikzDevice. I'm struggling with getting R graphs into LaTeX.

This is my code for pgfSweave Rnw file:

\documentclass{article}
\usepackage{tikz}
\usepackage{Sweave}
\usepackage[margin=1in]{geometry}

\title{Minimal pgfSweave Example}
\author{Cameron Bracken}

\begin{document}

<<setup,echo=F>>=
setCacheDir("cache")
options(keep.space=TRUE)
@


\maketitle
This example is identical to that in the Sweave manual and is intended to
introduce pgfSweave and highlight the basic differences. Please refer to
the pgfSweave vignette for more usage instructions.
We embed parts of the examples from the \texttt{kruskal.test} help page
into a \LaTeX{} document:

<<data,cache=T,tidy=T>>=
# hey, a comment
data(airquality)
print(kruskal.test(Ozone ~ Month, data = airquality )) # and another
@

\noindent which shows that the location parameter of the Ozone distribution varies
significantly from month to month. Finally we include a boxplot of the data:

\begin{figure}[!ht]
  \centering
  %notice the new options
  {\pgfkeys{/pgf/images/include external/.code=
    {\includegraphics[width=3in]{#1}}}

    <<boxplot, echo=T, fig=T, width=3, height=3, tikz=T, external=T, highlight=T>>=
      boxplot(Ozone ~ Month, data = airquality,
        main='Ozone distribution',xlab='Month',ylab='Concentration')
     @
   }% this brace ends the effect of `include external'
  \caption{This is from pgfSweave. Text is typset by \LaTeX\ and so matches the
           font of the document.}
\end{figure}

\end{document}

which produces

and the tikzDevice Rnw code is

\documentclass{article}
\usepackage{tikz}
\usepackage[nogin]{Sweave}

\begin{document}

<<echo=FALSE>>=
library(tikzDevice)
@

\begin{figure}[ht]
  \centering

  <<inline, echo=FALSE, results=tex>>=
  tikz(console=TRUE, width=5, height=5)
  x <- rnorm (100)
  plot(x)
  dummy <- dev.off()
  @

  \caption{caption}
  \label{fig:inline}
\end{figure}

\end{document}

which produces

My question is: What am I missing? Both Rnw codes do not produce R graphs in pdf to include in a LaTeX document. Any help will be highly appreciated.

Answer 1

In both cases, the Sweave chunks should not be indented.

When the Sweave driver (a part of R) parses the input file, it recognizes as chunks of R code blocks that begin with a << at the start of a line, and end with a @. Because your << is not at the start of a line, those blocks are never run as R code, and no plots are produced.