R devel - Sep 2007 - Call C code from R

Hello, All!
  
I'm new for R-devel list. And I'd like to ask some questions, 
maybe they will be stuped for the most part of members of the 
list.
I need to call function which is written in C++ from R.
My questions are:
1. How should I include libraries (for example, iomanip, 
sstream, iostream)?
2. Can I use namespace?
  
Thanks All :)
Olga

maybe try this page,

http://www.math.ncu.edu.tw/~chenwc/R_note/index.php?item=R_call

i'm not alrigth with this but i try

Christophe
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On Mon, 17 Sep 2007, ????? ?. ???????  wrote:
> Hello, All!
>
> I'm new for R-devel list. And I'd like to ask some questions,
> maybe they will be stuped for the most part of members of the
> list.
> I need to call function which is written in C++ from R.
Your subject line says C ....
> My questions are:
> 1. How should I include libraries (for example, iomanip,
> sstream, iostream)?
> 2. Can I use namespace?
What you link into R is a shared object aka DLL.  If you use the 
documented ways (e.g. R CMD CHLIB) to make this, it will be linked against 
the platform's standard C++ libraries.  There are lots of examples of C++ 
code in CRAN packages doing this.

The use of iostream is discussed in 'Writing R Extensions'.

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595

1) You include libraries just like you would always do. Here is the
example from my package that uses external libraries of ImageMagick and
GTK, standard libraries (stdio, pthread) and R libraries:

#include <R.h>
#include <Rdefines.h>
#include <R_ext/Rdynload.h>
#include <R_ext/Error.h>
#include <R_ext/Memory.h>

#include <magick/ImageMagick.h>

#include <stdio.h>

#ifndef WIN32
#   include <pthread.h>
#endif

/* These are to use GTK */
#ifdef USE_GTK
#   include <gtk/gtk.h>
#   ifdef WIN32
        typedef unsigned long ulong;
#       include <sys/types.h>
#   else
#       include <gdk/gdkx.h>
#   endif
#endif

2) The above is C code and no namespaces are used, however the piece
below is C++ code using namespaces and STL. With C++ you only need to
make sure that you export your function as C: extern "C" {}:

#include <R.h>
#include <Rdefines.h>
#include <R_ext/Rdynload.h>
#include <R_ext/Error.h>
#include <R_ext/Memory.h>

#include <magick/ImageMagick.h>

/* list of STL, C++ */
#include <list>

#define BG 0.0

struct TheSeed {
    int index, seed;
};

typedef std::list<int>     IntList;
typedef std::list<TheSeed> SeedList;


Oleg

On Mon, 2007-09-17 at 09:14 +0700, ????? ?. ???????
wrote:
> Hello, All!
>   
> I'm new for R-devel list. And I'd like to ask some questions, 
> maybe they will be stuped for the most part of members of the 
> list.
> I need to call function which is written in C++ from R.
> My questions are:
> 1. How should I include libraries (for example, iomanip, 
> sstream, iostream)?
> 2. Can I use namespace?
>   
> Thanks All :)
> Olga
> 
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
-- 
Dr Oleg Sklyar * EBI-EMBL, Cambridge CB10 1SD, UK * +44-1223-494466