R help - Feb 2007 - Help with interfacing C & R

Hi all,

I was trying to set up an interface for using C functions in R. For this, my R
file hello2.r is:

---------------------------------------------------------------------------------

hello2 <- function(n) {
.C("hello", as.integer(n))
}

hello2(3)
--------------------------------------------------------------------------------

and my hello.c file is:

------------------------------------------------------------------------------
#include <R.h>
void hello(int *n)
{
    int i;
    for(i=0; i < *n; i++) {
    Rprintf("Hello, world!\n");
    }
}
---------------------------------------------------------------------------
>From my windows command line, I execute:
> R CMD SHLIB hello.c
but I get the error message:
Error: syntax error in "R CMD". I am trying to look up information on
the web page at: 
http://cran.r-project.org/doc/manuals/R-exts.html#dyn_002eload-and-dyn_002eunload

As I understand it, I need to load some files, but I don't understand which
commands I need to execute to compile & execute my 'hello world'
code.

I am running R 2.4.0 on Windows XP machine.

Any help would be highly appreciated.

thanks!

 
---------------------------------
Food fight? Enjoy some healthy debate

	[[alternative HTML version deleted]]

On Windows you need:
  - download and install Cygwin (cygwin.com) with default options,
    supposedly you install into c:\cygwin. Add path to
    c:\cygwin\bin;c:\cygwin\lib to your system PATH
  - download and unpack Rtools
    (http://www.murdoch-sutherland.com/Rtools/tools.zip)
    Assuming you have them in C:\Rtools, add c:\RTools\bin
    to your PATH _in front of_ cygwin
  - download and install MinGW, you will want to get MinGW-5.1.3.exe,
    which will download and install the rest. You will want to select
    at least gcc and make. Add the path to c:\MinGW\bin to your system
    PATH, right in front of Rtools
    (http://sourceforge.net/projects/mingw/)
  - download and install ActivePerl from (activestate.com), ensure path
    is added to your PATH

For help files:
  - get MS hhc, comes as part of htmlhelp.exe from here:
http://www.microsoft.com/downloads/details.aspx?FamilyID=00535334-c8a6-452f-9aa0-d597d16580cc&DisplayLang=en
    this is Microsoft HTML Help Compiler, add path to it to your PATH
  - you might want to consider MikTex, dowload, install, add to path if
    you have a package and a help system a should be built

Be sure that when installing R you included sources for compilation! You 
might need to reinstall R. When this done, you can try executing R CMD 
SHLIB or R CMD build --binary if you have a package.

Please refer to "Writing R Extensions" (CRAN) for complete reference
and
to this guide for step-by-step description:

http://www.ebi.ac.uk/~osklyar/kb/CtoRinterfacingPrimer.pdf

Regards,
Oleg

--
Dr Oleg Sklyar | EBI-EMBL, Cambridge CB10 1SD, UK | +44-1223-494466


Tim Smith wrote:
> Hi all,
> 
> I was trying to set up an interface for using C functions in R. For this,
my R file hello2.r is:
> 
>
---------------------------------------------------------------------------------
> 
> hello2 <- function(n) {
> .C("hello", as.integer(n))
> }
> 
> hello2(3)
>
--------------------------------------------------------------------------------
> 
> and my hello.c file is:
> 
>
------------------------------------------------------------------------------
> #include <R.h>
> void hello(int *n)
> {
>     int i;
>     for(i=0; i < *n; i++) {
>     Rprintf("Hello, world!\n");
>     }
> }
> ---------------------------------------------------------------------------
> 
>>From my windows command line, I execute:
> 
>> R CMD SHLIB hello.c
> 
> but I get the error message:
> Error: syntax error in "R CMD". I am trying to look up
information on the web page at: 
http://cran.r-project.org/doc/manuals/R-exts.html#dyn_002eload-and-dyn_002eunload
> 
> As I understand it, I need to load some files, but I don't understand
which commands I need to execute to compile & execute my 'hello
world' code.
> 
> I am running R 2.4.0 on Windows XP machine.
> 
> Any help would be highly appreciated.
> 
> thanks!
> 
>  
> ---------------------------------
> Food fight? Enjoy some healthy debate
> 
> 	[[alternative HTML version deleted]]
> 
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