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Aaron, > Yes, I took a brief look at both versions of UDUNITS. Both UCUM and > UDUNITS take similar approaches to life by defining a language in which > to define units in relation to one another and by using this language to > define a baseline set. UCUM has one "central" XML file on their web > site and UDUNITS seems to have 5 or so as part of the library, but it is > much the same idea. Both have library support, but the primary language > in which they are implemented is different (C/C++ vs Java). > > The issue that comes to mind is that we will be using UDUNITS > (implicitly) with our gridded NetCDF (CF) files, but UCUM comes as a > best practice recommendation with GML data. We can make mappings > between the two if need be or use UDUNITS for both, but it would solve a > number of problems if they were reconciled in some way. There are > probably subtle distinctions in using UCUM vs UDUNITS that I am not yet > aware of, but right now it looks as if UDUNITS has more languages > supported in the library, heavy met/oceano (CF) use, and some associated > units not yet defined in UCUM, and UCUM has acceptance in the GML > community, a deep formal specification and reconciliation of a number of > ISO and ICAO specs. Some of the discussion hangs on whether UDUNITS is > aimed more towards a being standard/specification or more towards being > a library. I recommend using the full name for units and prefixes and staying away from abbreviations. That should minimize ambiguity. > I would be very interested in anything that comes up related to this > topic. We will be doing some further research in the near future that I > could send along or discuss if it is of interest. Feel free. Regards, Steve Emmerson Ticket Details =================== Ticket ID: OYS-245485 Department: Support UDUNITS Priority: Normal Status: Closed