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[netCDFJava #YHY-505756]: variable aggregation within a single dataset

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  • Subject: [netCDFJava #YHY-505756]: variable aggregation within a single dataset
  • Date: Wed, 14 Aug 2013 10:41:36 -0600
Ghansham,

In theory, your suggestion should work.  In practice, we will see how 
well the CDM handles a non-georeferencing coordinate axis.  We will be 
pleased to have a sample file when you have it assembled.

Regards,
   Lansing Madry
   Unidata
   Boulder, Colorado

On 8/13/2013 8:17 PM, ghansham sangar wrote:
> New Client Reply: variable aggregation within a single dataset
>
> Ok fine... let me give a try. It will be a great one if it works.
> Getting into more details, we have a geostationary sounder with radiance
> coming from as many as 18 IR channels.
> So I want to stack them with in a single file with radiance central
> wavelength as the dimension (where I will try to use
> the discrete axis concept.) Lets see if it works.
> If I use that then it should work with NetCDF-Java. (I mean does NCJ  has
> support for discrete axis built in?)
>
> Ghansham
>
>
> address@hidden> wrote:
>
>> Ghansham,
>>
>> I do not have a sample dataset with a discrete axis that I can think of
>> offhand.  If you were to create a new dimension (axis) for aggregation
>> using NcML, you would do it as described here:
>>
>>
>> http://www.unidata.ucar.edu/software/netcdf/ncml/v2.2/Aggregation.html#joinNew
>>
>> Note that you would not be able to do this inside of a single dataset, per
>> your original question.
>>
>> Regards,
>>    Lansing
>>
>>> Can you attach a sample datset or how discrete axis looks in ncml or
>>   cdl?
>>> Ghansham
>>>
>>> address@hidden> wrote:
>>>> Ghansham,
>>>>
>>>> As near as I might suggest, your wave number axis would probably fall
>>> under the description of a "discrete axis."  There is a discussion in the
>>> most recent CF document here:
>>>>
>> http://cf-pcmdi.llnl.gov/documents/cf-conventions/1.6/cf-conventions.html#discrete-axis
>>>> Regards,
>>>>    Lansing
>>>>
>>>>> Actually I dont want to go away from CF conventions. AFAIK wavenumber
>> has
>>>>> not been yet accepted as a standard dimension. If I am wrong in
>> stating
>>>>> that just let me know and I will go ahead to do that. I am more than
>>> happy
>>>>> doing that. It reduces the number of variable  in my file.
>>>>>
>>>>> regards
>>>>> Ghansham
>>>>>
>>>>>
>>>>> address@hidden> wrote:
>>>>>
>>>>>> Ghansham,
>>>>>>
>>>>>> I'm afraid that you will not be able to aggregate your variables as
>> you
>>>>>> are describing using NcML or any of our aggregation tools.  Your
>> best
>>>>>> solution is probably to rewrite the files with the wavenumber
>> dimension
>>>>>> included from the start.
>>>>>>
>>>>>> Regards,
>>>>>>    Lansing Madry
>>>>>>    Unidata
>>>>>>    Boulder, Colorado
>>>>>>
>>>>>>> R/Sir
>>>>>>>
>>>>>>> I have mulitple variables (3-d namely time, lat, lon) within a
>> single
>>>>>>> dataset, and I want to join them on fourth dimension wavenumber
>> (to
>>> be
>>>>>>> created in the dataset). Is it  possible using NcML or any other
>>> solution
>>>>>>>
>>>>>>> Ghansham
>>>>>>>
>>>>>>>
>>>>>>
>>>>>> Ticket Details
>>>>>> ===================
>>>>>> Ticket ID: YHY-505756
>>>>>> Department: Support netCDF Java
>>>>>> Priority: Critical
>>>>>> Status: Open
>>>>>>
>>>>>>
>>>>>
>>>>
>>>> Ticket Details
>>>> ===================
>>>> Ticket ID: YHY-505756
>>>> Department: Support netCDF Java
>>>> Priority: Critical
>>>> Status: Open
>>>>
>>>>
>>>
>>
>> Ticket Details
>> ===================
>> Ticket ID: YHY-505756
>> Department: Support netCDF Java
>> Priority: Critical
>> Status: Open
>>
>>
>
>
> Ticket Details
> ===================
> Ticket ID: YHY-505756
> Department: Support netCDF Java
> Priority: Critical
> Status: Open
> Link:  
> https://www.unidata.ucar.edu/esupport/staff/index.php?_m=tickets&_a=viewticket&ticketid=22278



Ticket Details
===================
Ticket ID: YHY-505756
Department: Support netCDF Java
Priority: Critical
Status: Open