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Using Processing and R together (in OS X)

I wanted to develop a small experiment with a front end using the Processing language and the backend calculations in R; the reason why will be another post. This post explained the steps assuming that one already has R and Processing installed:

  1. Install the Rserve package. This has to be done from source (e.g. using R CMD INSTALL packagename).
  2. Download Rserve jar files and include them in the Processing sketch.
  3. Run your code

For example, this generates 100 normal distributed random numbers in R and then sorts them (code copy and pasted from second link):

import org.rosuda.REngine.Rserve.*;
import org.rosuda.REngine.*;

double[] data;

void setup() {
size(300, 300);

try {
RConnection c = new RConnection();
// generate 100 normal distributed random numbers and then sort them
data= c.eval("sort(rnorm(100))").asDoubles();

} catch ( REXPMismatchException rme ) {
rme.printStackTrace();

} catch ( REngineException ree ) {
ree.printStackTrace();
}
}

void draw() {
background(255);
for( int i = 0; i < data.length; i++) {
line( i * 3.0, height/2, i* 3.0, height/2 - (float)data[i] * 50 );
}
}

The problem is that this didn't work, because my OS X (I use macs) R installation didn't have shared libraries. My not-so-quick solution was to compile R from source, which involved:

  1. Downloading R source. I went for the latest stable version, but I could have gone for the development one.
  2. Setting up the latest version of C and Fortran compilers. I did have an outdated version of Xcode in my macbook air, but decided to delete it because i- uses many GB of room in a small drive and ii- it's a monster download. Instead I went for Apple's Command Line Tools, which is a small fraction of size and do the job.
  3. In the case of gfortran, there are many sites pointing to this page that hosts a fairly outdated version, which was giving me all sorts of problems (e.g. "checking for Fortran 77 name-mangling scheme") because the versions between the C and Fortran compilers were out of whack. Instead, I downloaded the latest version from the GNU site.
  4. Changing the config.site file in a few places, ensuring that I had:
  5. CC="gcc -arch x86_64 -std=gnu99"
    CXX="g++ -arch x86_64"
    F77="gfortran -arch x86_64"
    FC="gfortran -arch x86_64"
    

Then compiled using (didn't want X11 and enabling shared library):

./configure --without-x --enable-R-shlib
make
make check
make pdf # This produces a lot of rubbish on screen and it isn't really needed
make info

And finally installed using:

sudo make prefix=/luis/compiled install

This used a prefix because I didn't want to replace my fully functioning R installation, but just having another one with shared libraries. If one types R in terminal then it is still calling the old version; the new one is called via /luis/compiled/R.framework/Versions/Current/Resources/bin/R. I then installed Rserve in the new version and was able to call R from processing so I could obtain.

A 'hello world' of the calling R from Processing world.
A 'hello world' of the calling R from Processing world.

Now I can move to what I really wanted to do. File under stuff-that-I-may-need-to-remember-one-day.

5 replies on “Using Processing and R together (in OS X)”

Hi Luis,
I manage my installation of R on my mac using homebrew. Because homebrew builds R from source anyway, it was easy to just add the –enable-R-shlib option to the standard build script by using the “brew edit r” command. Thanks for the interesting post!

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