This message came from the CF Trac system. Do not reply. Instead, enter your comments in the CF Trac system at https://cf-pcmdi.llnl.gov/trac/.
#101: Correct error in introductory text of Section 4.4 -- definition of 'year' -----------------------------+---------------------------------------------- Reporter: stevehankin | Owner: [email protected] Type: defect | Status: new Priority: medium | Milestone: Component: cf-conventions | Version: Resolution: | Keywords: -----------------------------+---------------------------------------------- Comment (by jonathan): Dear Steve Sorry to be awkward, but I don't think we can do that. CF adopted udunits as the arbiter of how units should be interpreted, and redefining the unit of `year` would therefore be a backward-incompatible change. It would affect existing files if it was interpreted as applying retrospectively, even if that was not the intention. In CF section 4.4 we currently recommend that caution is necessary with the units of `year` and `month`, because of the definition, which catches people out. I'd like to suggest that we change this recommendation to a '''prohibition''' of the units of `year` and `month` in the next version of CF. The CF checker could detect that, and we could remove these units from a CF version of the udunits database. For uses where `year` and `month` are to be interpreted in a calendar- dependent way, we could introduce an alternative syntax for units of time, not related to udunits. John Caron suggested one a while ago, and has implemented it in Java I think, but it's not been put forward as a CF convention. This involves some extra rules e.g. to decide what is meant by 31 Jan 2013 plus 1 calendar month, or 29 Feb 2012 plus 1 calendar year. Neither of the above could be done as a defect ticket, because they change the convention. If you or others think we should proceed with this, we could change the status of this ticket to make a new proposal, or start a new ticket. Cheers Jonathan -- Ticket URL: <https://cf-pcmdi.llnl.gov/trac/ticket/101#comment:5> CF Metadata <http://cf-pcmdi.llnl.gov/> CF Metadata This message came from the CF Trac system. To unsubscribe, without unsubscribing to the regular cf-metadata list, send a message to "[email protected]" with "unsubscribe cf-metadata" in the body of your message.
