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John, > Hi all, > > I'm trying to document for our users what units should be used with CF > netCDF files. > > CF declares that only those units supported by CF are acceptable. They > helpfully point to this page to determine what those units are: > > http://www.unidata.ucar.edu/software/udunits/udunits-2-units.html > > My first observation is that this page has 5 links, that currently are > broken. So that's the thing that needs fixing ASAP. This is a common problem with on-line documentation: links to highly specific information often break when the documentation is restructured (which it was). The relevant on-line links are now (in order from most robust but general to most fragile but specific): http://www.unidata.ucar.edu/software/udunits http://www.unidata.ucar.edu/software/udunits/udunits-current/doc/udunits http://www.unidata.ucar.edu/software/udunits/udunits-current/doc/udunits/udunits2.html http://www.unidata.ucar.edu/software/udunits/udunits-current/doc/udunits/udunits2.html#Database > As I recall, though, once that is fixed, the users don't actually see a > list of acceptable units. They will see XML files, which are hard for > many to parse to even get a clue. To my knowledge, there is no page that > lists the values in each of those 5 XML tables, perhaps in user-readable > HTML tables. In the past, I've had to build that myself. That's a good idea that, unfortunately, has a lower priority than some other ideas (we're a small shop; UDUNITS has much less than one person working on it). It might be possible to accomplish this via XSLT. I'll have a talk with an expert. > And once the terms from those 5 pages are in visible form, it is still > hard to tell what legal units look like. Data in particular can have a > few different forms, as I recall. There does not appear to be > information that summarizes all of this in one place. The section on unit syntax <https://www.unidata.ucar.edu/software/udunits/udunits-current/doc/udunits/udunits2lib.html#Syntax> is insufficient? What, specifically, would you like to see? > Is there any chance Unidata could find some resources to pull together > user-facing documentation that makes 'unit-hunting' trivial for the > non-technical user? We're peddling as fast as we can. :-) Your email should help. > john > > ------------------------------------ > John Graybeal > Sr. Data Manager, Metadata & Semantics > > M +1 408 675-5445 > skype: graybealski > Marinexplore > 920 Stewart Drive > Sunnyvale 94085 > California, USA > www.marinexplore.com Regards, Steve Emmerson Ticket Details =================== Ticket ID: CEJ-221616 Department: Support UDUNITS Priority: Normal Status: Closed