Rpy2 can't find my R libraries on install
Question: R built from source, installed locally. R is at `~/bin/R` (which is in my
PATH) and its libraries are in `~/lib64/R/`. Installing rpy2 should be simple.
It finds the correct R just fine (as it's in the path). Then it can't find the
libraries.

    
    
    $python setup.py build install
    R version 3.2.1 (2015-06-18) -- "World-Famous Astronaut"
    
    ...
    
    setup.py:211: UserWarning: No include specified
      warnings.warn('No include specified')
    setup.py:222: UserWarning: No libraries as -l arguments to the compiler.
      warnings.warn('No libraries as -l arguments to the compiler.')
    
        Compilation parameters for rpy2's C components:
            include_dirs    = []
            library_dirs    = []
            libraries       = []
            extra_link_args = []
    

And then we get a million errors that it can't find functions that are in the
R libraries.

Rpy2's [documentation says](http://rpy.sourceforge.net/rpy2/doc-
dev/html/overview.html) there's a simple option for designating where R or its
libraries are:

    
    
    python setup.py build --r-home ~/lib64/R/lib install
    

But if you do this, then you get:

    
    
    setup.py:222: UserWarning: No libraries as -l arguments to the compiler.
      warnings.warn('No libraries as -l arguments to the compiler.')
    
        Compilation parameters for rpy2's C components:
            include_dirs    = []
            library_dirs    = []
            libraries       = []
            extra_link_args = []
    
    usage: setup.py [global_opts] cmd1 [cmd1_opts] [cmd2 [cmd2_opts] ...]
       or: setup.py --help [cmd1 cmd2 ...]
       or: setup.py --help-commands
       or: setup.py cmd --help
    
    error: option --r-home not recognized
    

It looks like the `--r-home` functionality has been removed. How does one
point rpy2 to the correct libraries?

* * *

Edit:

Have now installed R with:

    
    
    ./configure --prefix=${HOME} --enable-R-shlib
    make
    make install
    

After that, I can install rpy2 with just `pip install rpy2`. But then, we're
still having library problems:

    
    
    import rpy2.robjects as robjects
    ImportError: libRblas.so: cannot open shared object file: No such file or directory
    

So then I needed to add this to my path:

    
    
    export LD_LIBRARY_PATH="~/lib64/R/lib:$LD_LIBRARY_PATH"
    

And then everything works!


Answer: If R is in an unconventional location, the easiest might be help out a bit by
setting environment variables (older versions of the doc is talking about
`--r-home` but this was a less tested corner and it was removed).

Try:

    
    
    export PATH=~/bin/R:${PATH}
    export LD_LIBRARY_PATH=~/lib64/R/lib:${LD_LIBRARY_PATH}
    export PKG_CONFIG_PATH=~/lib64/R/lib/pkgconfig/:${PKG_CONFIG_PATH}
    

