{Hijacking the thread from from R-help to R-devel -- as I am consciously shifting the focus away from the original question ... }
>>>>> David Winsemius <dwinsem...@comcast.net> >>>>> on Tue, 10 Aug 2010 08:42:12 -0400 writes: > On Aug 9, 2010, at 2:45 PM, Theo Tannen wrote: >> Are integers strictly a signed 32 bit number on R even if >> I am running a 64 bit version of R on a x86_64 bit >> machine? >> >> I ask because I have integers stored in a hdf5 file where >> some of the data is 64 bit integers. When I read that >> into R using the hdf5 library it seems any integer >> greater than 2**31 returns NA. > That's the limit. It's hard coded and not affected by the > memory pointer size. >> >> Any solutions? > I have heard of packages that handle "big numbers". A bit > of searching produces suggestions to look at gmp on CRAN > and Rmpfr on R-Forge. Note that Rmpfr has been on CRAN, too, for a while now. If you only need large integers (and rationals), 'gmp' is enough though. *However* note that the gmp or Rmpfr (or any other arbitray precision) implementation will be considerably slower in usage than if there was native 64-bit integer support. Introducing 64-bit integers natively into "base R" is an "interesting" project, notably if we also allowed using them for indices, and changed the internal structures to use them instead of 32-bit. This would allow to free ourselves from the increasingly relevant maximum-atomic-object-length = 2^31 problem. The latter is something we have planned to address, possibly for R 3.0. However, for that, using 64-bit integers is just one possibility, another being to use "double precision integers". Personally, I'd prefer the "long long" (64-bit) integers quite a bit, but there are other considerations, e.g., one big challenge will be to go there in a way such that not all R packages using compiled code will have to be patched extensively... another aspect is how the BLAS / Lapack team will address the problem. Martin Maechler, ETH Zurich ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel