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Re: NCML aggregation and variableAgg

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  • Subject: Re: NCML aggregation and variableAgg
  • Date: Wed, 04 Oct 2006 12:56:03 -0600
Its hard to do this in a general way, many files do not use the coordinate 
variable convention (variable name same as the dimension name). Can you give me 
some use cases about what exactly would work for your situation, perhaps with 
some example files?

Jon Blower wrote:

Hi John,

I see your point about coordinate variables.  However it would be nice
to be able to say "aggregate over all non-coordinate variable".
Unless there's something I'm missing, I would have thought that this
was a very common case.

Thanks, Jon

On 03/10/06, John Caron <address@hidden> wrote:


Hi Jon:

How do you distinguish between variables that should be aggregated and
those that shouldnt? for example, often adding a time dimension to the
coordinate variables screws things up for some software.

address@hidden wrote:

>Hi all,
>
>I'm creating aggregations of NetCDF files by aggregating on a new time
>dimension, whose values come from the names of the files. My .ncml file looks 
>like this:
>
><netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2";>
>  <aggregation dimName="time" type="joinNew">
>    <variableAgg name="ICEC"/>
>    <variableAgg name="ICETK"/>
>    <variableAgg name="M"/>
>    <variableAgg name="...etc"/>
>    <scan location="C:/data/FOAM_one/" suffix=".nc"
>dateFormatMark="FOAM_#yyyyMMdd.HH" />
>  </aggregation>
></netcdf>
>
>It's a bit tedious to have to specify explicitly all the variables I want to >aggregate. I want to aggregate all variables so I would like to be able to 
>have:
>
><netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2";>
>  <aggregation dimName="time" type="joinNew">
>    <variableAgg name="*"/>
>    <scan location="C:/data/FOAM_one/" suffix=".nc"
>dateFormatMark="FOAM_#yyyyMMdd.HH" />
>  </aggregation>
></netcdf>
>
>or something like that. Is this possible? If I try that, no variables get 
>aggregated (when I open a GridDataset, there is no time dimension).
>
>Thanks in advance,
>Jon
>