[R] tree in tree package - Error: cannot allocate vector of size 2.0 Gb

[Stephen Sefick]

R version 3.0.0 (2013-04-03)
Platform: x86_64-redhat-linux-gnu (64-bit)

locale:
  [1] LC_CTYPE=en_US.utf8       LC_NUMERIC=C
  [3] LC_TIME=en_US.utf8        LC_COLLATE=en_US.utf8
  [5] LC_MONETARY=en_US.utf8    LC_MESSAGES=en_US.utf8
  [7] LC_PAPER=C                LC_NAME=C
  [9] LC_ADDRESS=C              LC_TELEPHONE=C
[11] LC_MEASUREMENT=en_US.utf8 LC_IDENTIFICATION=C

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base


6GB RAM, intel core2 quad, Scientific Linux 6.4

I am using tree in the tree package.  and I get the following error:

Error: cannot allocate vector of size 2.0 Gb

shouldn't I be able to allocate more memory than 2GB?  I am sure that I 
am missing something.  Any help would be greatly appreciated.
kind regards,

-- 
Stephen Sefick
**************************************************
Auburn University
Biological Sciences
331 Funchess Hall
Auburn, Alabama
36849
**************************************************
sas0025 at auburn.edu
http://www.auburn.edu/~sas0025
**************************************************

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us feel like gods.  We are mammals, and have not exhausted the annoying 
little problems of being mammals.

                                 -K. Mullis

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