[R] Sweave: Changing the background color, adding a border

[Romain Francois]

Christophe Genolini wrote:
> Hi all,
>
> I am using Sweave to produce a document. Unfortunately, I have to 
> print several copies and I can't print them in color. So I would like 
> to change the way of printing the code. I would like to print the code 
> in a box with a black borderline and a grey background (quite 
> classic). Is it possible to do it by changing some Schunk options?
>
> Christophe
>
Hi Christophe,

This is not a trivial task, \Sinput and \Soutput environments are 
basically verbatim environments. You might want to have a look at the 
highlight package (not on CRAN yet) 
http://r-forge.r-project.org/R/?group_id=384 which ships a sweave driver 
that does some syntax highlighting of the code and does not rely on semi 
verbatim environments:

require( grid )
require( highlight, lib = "~/.R/library" )
v <- vignette( "grid", package = "grid" )
file.copy( v$file, "grid.Snw" )
Sweave( "grid.Snw", driver = HighlightWeaveLatex( ) )

See the result here: addictedtor.free.fr/misc/grid.pdf

The driver writes Hinput and Houtput environments instead of Sinput and 
Soutput, and they are defined as this in the preamble:

\newenvironment{Hinput}%
{}%
{}%
\newenvironment{Houtput}%
{}%
{}%

So you might imagine to redefine them using some combination of 
fcolorbox and minipage.

What happens with the box if the code spans more than one page ?

Romain

-- 
Romain Francois
Independent R Consultant
+33(0) 6 28 91 30 30
http://romainfrancois.blog.free.fr