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[UDUNITS #OYS-245485]: Udunits and UCUM

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  • Subject: [UDUNITS #OYS-245485]: Udunits and UCUM
  • Date: Wed, 30 Jul 2008 15:15:30 -0600
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