[R] running R UNIX in a mac computer

[Jari Oksanen]

On Fri, 2004-06-11 at 03:49, Tiago R Magalhaes wrote:
> Hi to you all
> 
> My question is:
> 
> there is a package written in UNIX for which there is no Mac version.
> 
> I would like to know if it's possible to install the R UNIX version on the
> MacOSX and run that UNIX package on my Mac (through this UNIX R Vresion on
> a Mac)
> 
> I have seen a porfile for r version 1.8.1 on darwin:
> http://r.darwinports.com/
> is that it?
> 
> aother question related to that
> if it's possible to use UNIX R in Mac, does anyone know how fast or how
> slow that is?

Tiago,

If it is a CRAN package *without* MacOS version, there obviously is a
reason for this handicap, and you cannot run the package. If it is a
stray package, its developer probably just doesn't have opportunity or
will to build a Mac binary, but you can build it yourself if you're
lucky. Check the FAQ and ReadMe files with your R/Aqua version to see
what you need. With little trouble you can easily use source packages
with your Mac R. Many tools are already installed in your OS (perl at
least). If the package has only R files, you may be able to install a
source package directly. If it has C source code, you should first
install MacOS X Developer tools (XCode): it comes with your OS
installation CD/DVD, but it is not installed by default. If the package
has Fortran source code, you got to find external Fortran compiler:
MacOS X ships with C compiler, but without Fortran compiler. See the Mac
R FAQ for the best alternatives to find the compiler (this FAQ is
installed with your R).

Installing a Darwin R orobably won't help you. It needs and uses exactly
the same tools to build the packages as R/Aqua. If you can't install a
source package in R/Aqua, you cannot install it in R/Darwin, and vice
versa. The toolset is the decisive part, not the R shell. I assume that
both versions of R are just as fast (or slow). R/Aqua uses highly
optimized BLAS for numeric functions, and if R/Darwin uses the same
library, it is just as fast. If it doesn't use optimized BLAS, it will
be clearly slower. 

I have installed Linux in Mac, but I found out that R was clearly (20%)
slower in Linux than in MacOS in the very same piece of hardware. The
main reason seemed to be that Linux R didn't have optimized BLAS because
the largest differences were in functions calling svd and qr (I used
YellowDog Linux) -- the Linux version took 150%(!) longer to run the
same svd-heavy test code. Another reason seemed to be that the Fortran
compiler produces much slower code in Linux than in MacOS X (difference
about 20%).

cheers, jari oksanen
-- 
Jari Oksanen <jarioksa at sun3.oulu.fi>