Trying to load into R, via rPython (http://rpython.r-forge.r-project.org/), a Python module that depends on rpy2, fails because rpy2 unconditionally tries to initialize R when this has already been done:
$ R -q > library('rPython'); python.exec('import rpy2.robjects') R is already initialized
I don't know how easy it would be to add a check for an already initialized R process and reuse it.
Funnily enough, doing this the other way round works, because Py_Initialize (called by rPython) can be called multiple times.
$ python Python 3.4.3 (default, Mar 25 2015, 17:13:50) [GCC 4.9.2 20150304 (prerelease)] on linux Type "help", "copyright", "credits" or "license" for more information. >>> from rpy2.robjects.packages import importr >>> rPy = importr("rPython") >>> rPy.python_exec("print(rPy)") rpy2.robjecs.packages.Package as a <module 'rPython'> rpy2.rinterface.NULL