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Hi Morgan, > I'm a graduate student at MIT and I've just started working with some very > large hurricane model output data. I found your email on the Unidata website > and thought you might be able to help me. > > I have a number of compressed output files that I can convert to netcdf > using a pgf90 (*pgf90 filename.f -o filename -Mbyteswapio -I${INC_NETCDF} > -L${LIB_NETCDF} -lnetcdf*). Each file is a little larger than 2GB, and the > final variable I need is not retained in the subsequent netcdf file. From > what I've just read, it seems as though the 64-bit LFS would let the netcdf > file hold all of the variables. What option should I add to the conversion > (copied above) to switch the format? If you're asking about writing netCDF-3 files that make use of LFS to support 64-bit file offsets, you have to provide a flag to the nf_create() (or nf90_create()) function to indicate your use of that variant of the "netCDF-3 classic" format, e.g. see the answer to this FAQ: How do I create a 64-bit offset netCDF file from C, Fortran-77, Fortran-90, or C++? http://www.unidata.ucar.edu/software/netcdf/docs/faq.html#Large%20File%20Support8 Even with the 64-bit offset netCDF-3 file format, there are some limitations on variable sizes: http://www.unidata.ucar.edu/software/netcdf/docs/faq.html#Large%20File%20Support10 There are other answers in that section of the FAQ http://www.unidata.ucar.edu/software/netcdf/docs/faq.html#Large%20File%20Support that may help if I've misunderstood your question. Otherwise, we'll need more specifics about your converion program. --Russ Russ Rew UCAR Unidata Program address@hidden http://www.unidata.ucar.edu Ticket Details =================== Ticket ID: DON-496465 Department: Support netCDF Priority: Normal Status: Closed