[R] How Can I Tell if the R Running is 64 bit or 32 bit?

[Prof Brian Ripley]

On Fri, 8 Aug 2008, Peter Dalgaard wrote:

> Marc Schwartz wrote:
>> Try:
>> 
>> > 8*4
>> [1] 32
>> 
>> As per the help page for .Machine:
>>
>>   sizeof.pointer     the number of *bytes* in a C SEXP type.
>> So:
>>
>>   8 bits per byte * 4 bytes = 32 bits
>> 
> Also (outside of R) type "uname -a". This should give something like
>
> Linux viggo 2.6.18.8-0.10-default #1 SMP Wed Jun 4 15:46:34 UTC 2008 x86_64 
> x86_64 x86_64 GNU/Linux
>
> on a 64-bit system (SUSE in this case)

Note though that you can run 32-bit R on a 64-bit system, and telling the 
pointer size from uname -a is trickier on other OSes.  E.g. a Solaris box 
says

blackhawk% uname -a
SunOS blackhawk 5.10 Generic_137112-04 i86pc i386 i86pc

Or on Mac OS

blacklark% uname -a
Darwin blacklark.stats.ox.ac.uk 9.4.0 Darwin Kernel Version 9.4.0: Mon Jun 
9 19:30:53 PDT 2008; root:xnu-1228.5.20~1/RELEASE_I386 i386

and I run both 32- and 64-bit R on both those systems.  Thus you do need 
to ask the R binary.

>
> but
>
> Linux turmalin 2.6.22.18-0.2-default #1 SMP 2008-06-09 13:53:20 +0200 i686 
> i686 i386 GNU/Linux
>
> on 32-bitters
>> 
>> :-)
>> 
>> HTH,
>> 
>> Marc Schwartz
>> 
>> 
>> on 08/08/2008 03:58 PM milton ruser wrote:
>>> Dear Prof. B.Ripley,
>>> 
>>> If :
>>>> .Machine$sizeof.pointer
>>> [1] 4
>>>> 2*2*2*2
>>> [1] 16
>>> 
>>> So I am running with 16 bits?
>>> 
>>> How can I know the number of bits supported on my machine?
>>> 
>>> Kindly,
>>> 
>>> miltinho astronauta
>>> brazil
>>> 
>>> On 8/8/08, Prof Brian Ripley <ripley at stats.ox.ac.uk> wrote:
>>>> Look at .Machine$sizeof.pointer (in bytes).
>>>> 
>>>> On Fri, 8 Aug 2008, Tom La Bone wrote:
>>>> 
>>>> 
>>>>> I think I installed 64-bit Ubuntu 8.04 and 64-bit R on my computer. I
>>>>> can't
>>>>> seem to find anything that says "this is 64-bit Ubuntu" or "this is 
>>>>> 64-bit
>>>>> R". How do I tell what version of R I am running?
>>>>> 
>>>>> Tom
>> 
>> ______________________________________________
>> R-help at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide 
>> http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>
>
> --
>  O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
> c/ /'_ --- Dept. of Biostatistics     PO Box 2099, 1014 Cph. K
> (*) \(*) -- University of Copenhagen   Denmark      Ph:  (+45) 35327918
> ~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)              FAX: (+45) 35327907
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595