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Hi Brian, > In a recent post about the NC_UNLIM dimension and sub_records, you > mentioned that netCDF 3 is planned. You mentioned packed data types, what > does this mean? It means you will be able to store arrays of n-bit data compactly, and you will be able to request the type of data you want without knowing how it is stored. For example, you will be able to request data from a variable as an array of floating-point numbers without knowing or caring that the data was stored as ints, longs, doubles, or 21-bit packed and scaled integers. Here's some more info, but these are planning documents that are still in draft form (we've already changed the naming convention for the new functions from what's in these documents), so please don't start programming to these interfaces yet! (-: http://www.unidata.ucar.edu/staff/hld/iita/packing.html http://www.unidata.ucar.edu/packages/netcdf/iita/summary-1996-04-30.html http://www.unidata.ucar.edu/packages/netcdf/iita/plans-index.html The last URL is a presentation that reveals some early plans for netCDF 3, 4, and 4+, but we're getting ready to refine these plans and get some feedback on a second iteration at a meeting with some interested users on May 17. After that, things may be ready to post some of these plans to the netcdfgroup mailing list to get other users reactions, but we had to first present this stuff to a group that is helping fund the development. --Russ