[udunits] Understanding and/or editing the UDUNITS2 xml data files

• To: "udunits@xxxxxxxxxxxxxxxx" <udunits@xxxxxxxxxxxxxxxx>
• Subject: [udunits] Understanding and/or editing the UDUNITS2 xml data files
• From: "EVANS, Colin (NHS DIGITAL)" <colin.evans@xxxxxxx>
• Date: Fri, 1 Mar 2019 00:19:54 +0000

I am new to udunits2 and trying to get to grips with how the system works.
The udunits2 documentation seems to provide very little information on how the 
XML files that define the units database are built. In order to understand this 
better I have been attempting to process these files through XLST into a flat 
delimited format. This has raised quite a few questions.
There are several things in these files I don't understand, from units that 
have multiple symbols assigned that are NOT defined as synonyms of a single 
canonical symbol, to other units that have no defined symbol or name at all, 
but exist only as a bundle of synonyms (?!)
I have tried to search the mailing list archive, but unfortunately the search 
page<https://www.unidata.ucar.edu/search.jsp?hq=site%3Awww.unidata.ucar.edu%2Fmailing_lists%2Farchives%2Fudunits&locationName=udunits+mailing+list+archives&cx=008424664622949020059%3Aafj38jxaljc&cof=FORID%3A9&ie=UTF-8&q=database&sa=search>
 on the UCAR web site seems to be searching the whole site, not just this 
mailing list (despite choosing that option) so any useful hits are buried in 
non-relevant results. The alternative of reading through the 10 years of 
archives one thread at a time is going to take a very long time...

I'm hoping this is a subject that has been discussed before, and someone might 
be able to point me to some guidelines on how to understand, and potentially 
extend, the units database.

Any hints or pointers will be very welcome.


Regards-

Colin Evans
Senior Business Analyst
Digital Diagnostics
NHS Digital
colin.evans@xxxxxxx<mailto:colin.evans@xxxxxxx>
07766 496929
www.digital.nhs.uk<http://www.digital.nhs.uk/>
@NHSDigital<https://twitter.com/nhsdigital>
General enquiries:0300 303 5678
enquiries@xxxxxxxxxxxxxxxxx<mailto:enquiries@xxxxxxxxxxxxxxxxx>



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