Dead John and Steve,
Yes, I suppose it is not a dimensional quantity. I am not sure what is
meant by this concept, I just assumed it was a variable with dimensions
(not a scalar). But I suppose it means something that can refer to a
physical property of the four-dimensional space-time.
However, when I send a file to the CF-checker, using the profile
variable as is shown in the example, I get a warning:
WARNING (3.1): units attribute should be present
I have tried both checkers, but none of them are ready for CF 1.6
checking yet. I got the above warning for CF 1.4 and CF 1.5 respectively.
Maybe the warning will disappear when checking against 1.6 is ready.
But this type of array (with some type of identifiers) will often appear
outside the context of Discrete Sampling Geometries. Surely the warning
about units for such variables is not appropriate.
For my test file, I also got this error:
ERROR (5): co-ordinate variable 'profile' not monotonic
I would think that monotonicity for such arrays is not important, but
this is maybe another discussion.
Best regards,
Egil
> My first thought is that its not a dimensional quantity. Why do you
> think it is?
>
> John
>
> Units of physical quantities are only meaningful for physical quantities (yes, I know that's a tautology :-). Is the "profile_id" a physical quantity? I wouldn't think so from its name. If it isn't, then a unit attribute would be meaningless and possibly misleading.
>
> Regards,
> Steve Emmerson
> On 2/16/2012 8:00 AM, Egil St?ren wrote:
>> From the CF 1.6 Convention, chapter 3.1 Units:
>>
>> "The units attribute is required for all variables that represent
>> dimensional quantities (except for boundary variables defined in
>> Section 7.1, ?Cell Boundaries? and climatology variables defined in
>> Section 7.4, ?Climatological Statistics?)."
>>
>> In the same document, in appendix H.3.4. Contiguous ragged array
>> representation of profiles, the following example appears:
>>
>> int profile(profile) ;
>> profile:cf_role = "profile_id";
>>
>> This array obviously contains identification numbers. It is also a
>> dimensional quantity and accordinly the units attribute is mandatory
>> (none of the listed exceptions apply). Are there any unit acceptable
>> by udunits that can be used in this case? The best I have found is
>> "count" which I think is misleading.
>>
>> Or should this and similar variables also be included in the list of
>> exceptions above?
>>
>> Best regards,
>>
>> Egil St?ren
>> met.no
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Received on Fri Feb 17 2012 - 04:10:20 GMT
