Hi John,
Thanks for your advice.
For a single vertical profile and single valued time, lat, long.
it seems there are two acceptable ways i.e 1 element vector or single valued
scalar.
Quoting from 'section 2.4 Dimensions' of CF standard:
1 element vector:
"Dimensions may be of any size, including unity. When a single value of some
coordinate applies to all the values in a variable, the recommended means of
attaching this information to the variable is by use of a dimension of size
unity with a one-element coordinate variable.
and in the next sentence a scalar:
"It is also acceptable to use a scalar coordinate variable which eliminates the
need for an associated size one dimension in the data variable."
1) ***Vector co-ordinate variables*******
Dimensions:
time=1
pressure=56
lat=1
lon=1
Variables:
time(time)
lat(lat)
lon(lon)
temperature(pressure)
2) **Scalar co-ordinate varaibles****
Dimensions:
pressure =56
Variables:
time
lat
lon
temperature(pressure)
The scalar approach you suggest as in section "H.3.3. Single profile" of the CF
v1.6 standard
is simpler than the vector approach so we will take your advice.
Regards,
Andrew
----- Original Message -----
From: "John Caron" <caron at unidata.ucar.edu>
To: "andrew walsh" <awalsh at metoc.gov.au>
Cc: <cf-metadata at cgd.ucar.edu>; "Luke Callcut" <luke at metoc.gov.au>;
<greg at metoc.gov.au>
Sent: Thursday, April 26, 2012 10:48 AM
Subject: Re: [CF-metadata] Ocean CTD data following CF Conventions v1.6
> Hi andrew:
>
> The file you sent (20110818T001140Z_M_HI504BEN.nc) appears to be a single
> profile. Assuming that, you would use the following template:
>
> http://cf-pcmdi.llnl.gov/documents/cf-conventions/1.6/cf-conventions.html#idp8363696
>
> note that lat, lon and time coordinates all have to be scalars.
>
> John
>
> On 4/18/2012 8:24 PM, andrew walsh wrote:
>> Hi John,
>>
>> We have now constructed a real netCDF file for you to check. QC flag
>> variables have been added in. The QC flagging method is based on the
>> proposed IODE scheme in (1) below.
>>
>> Attached are the sample .nc file, text (ncdump) of same and a document
>> specifying the CDL.
>>
>> Thanks and Regards,
>>
>> Andrew Walsh
>>
>>
>> Ref.
>>
>> (1) Konovalov et. al (March 2012), Proposal to adopt a quality flag scheme
>> standard
>> for oceanographic and marine meteorological data, Version 1.2.
>>
>> ----- Original Message ----- From: "John Caron" <caron at unidata.ucar.edu>
>> To: "andrew walsh" <awalsh at metoc.gov.au>
>> Sent: Thursday, April 05, 2012 10:44 AM
>> Subject: Re: [CF-metadata] Ocean CTD data following CF Conventions v1.6
>>
>>
>>> ok
>>>
>>> On 4/4/2012 6:42 PM, andrew walsh wrote:
>>>> Hi John,
>>>>
>>>> Thank for your offer to check a sample netCDF CTD data file. At moment we
>>>> don't have
>>>> some real .nc file but when we do I can send you a file for checking.
>>>>
>>>> Andrew
>>>>
>>>> ----- Original Message ----- From: John Caron
>>>> To: cf-metadata at cgd.ucar.edu
>>>> Sent: Wednesday, April 04, 2012 5:55 AM
>>>> Subject: Re: [CF-metadata] Ocean CTD data following CF Conventions v1.6
>>>>
>>>>
>>>> Hi all:
>>>>
>>>> Lets see, I havent followed the entire conversation, but:
>>>>
>>>> 1) Andrew if you can send me a sample file (not just the CDL) I can check
>>>> if it works in the CDM with the new 1.6 conventions, and maybe give you
>>>> some advice from my POV.
>>>>
>>>> 2) Aggregation in the CDM comes in 2 flavors. 1) The original
>>>> implementation simply appends multidimensional arrays together, eg "joinNew
>>>> " and "joinExisting" NCML aggregation. I call it "syntactic aggregation"
>>>> because it doesnt know what its aggregating, and the homogeneity
>>>> requirements are strict. 2) "Feature Type collections" (aka "semantic
>>>> aggregation") are the more recent development. These understand the
>>>> coordinate information of the data, and so can handle variations in the
>>>> representation, eg ragged arrays, scalar coordinates, etc. In this case,
>>>> the CDM understands a dataset as a collection of "features objects", which
>>>> can be stored in a collection of files. The interfaces to these
>>>> collections is still under development. Most current and future work in the
>>>> CDM is in this category.
>>>>
>>>> John
>>>>
>>>> snip ....
>>>> _______________________________________________
>>>> CF-metadata mailing list
>>>> CF-metadata at cgd.ucar.edu
>>>> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
>>>
>>>
>
>
Received on Fri Apr 27 2012 - 00:03:28 BST
