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/.
#104: Clarify the interpretation of scalar coordinate variables -----------------------------+---------------------------------------------- Reporter: jonathan | Owner: [email protected] Type: defect | Status: new Priority: medium | Milestone: Component: cf-conventions | Version: Resolution: | Keywords: -----------------------------+---------------------------------------------- Comment (by davidhassell): Replying to [comment:13 markh]: Dear Mark, Thank you for posting an example, especially one which also describes the position that Jonathan and I are stating. > This interpretation does not adequately reflect the data and metadata. It defines a set of independent coordinates which were not intended to be independent by the data creator. Interesting that you should say this. If the creator had intended for some of these size one coordinates to be dependent, I rather think that they should have indicated this when they created the dataset, by giving them a shared dimension. How else can we know what the creator intended? A human can try to infer (correctly?), but a computer can't. For example, I might presume from their names that you mean `a`, `p0` and `b` to be related height coordinates (but as the data variable varible is surface pressure, I'm not 100% sure ...). If so, then these should have been written as something like the size 1, 1-d coordinates `a(height)`, `p0(height)`, `b(height)` and don't need to be listed in the `coordinates` attribute. > If the data creators had been shown an 11 dimensional data set when they created it, they would have very likely raised questions about the output, but the scalar coordinate variable has not been interpreted in this way. The first encoding appeared to people to be a logical and sensible representation of their data. ... and perhaps wished that they had clearly encoded the relationships between dependent variables when they created the file in the first place. You seem to ackowledge that the creator meant to indicate that some coordinates are related, but has neglected to encode this in the file. Given that we have a mechanism for linking dependent size 1 coordinates (via a shared dimension), if no link is specified then I prefer the only unambiguous interpretation: the exact opposite - i.e. they are independent. I would rather not change the convention just to attach credibility to some datasets which were unintentionally created without all of the relevent information. All the best, David -- Ticket URL: <https://cf-pcmdi.llnl.gov/trac/ticket/104#comment:14> 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.
