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[netCDFJava #HIP-291542]: Question on NcML aggregation

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  • Subject: [netCDFJava #HIP-291542]: Question on NcML aggregation
  • Date: Fri, 29 Mar 2013 14:37:22 -0600
Matt,

If you send me a few of the files, I can set up the aggregation and see if 
there are any pitfalls in the data.  It's not always straightforward.

-Lansing

> Lansing,
> 
> The times "should be" unified, but I should look into that. Probably, to
> avoid complications a JoinNew would suffice in this case.
> 
> Matt
> 
> 
> address@hidden> wrote:
> 
> > Li,
> >
> > Are the times in the data sets unified (i.e., all the same), or are they
> > interlaced?  In other words, if you were to set up a single time axis for
> > all of the buoys, would the data line up on the axis, or would it be
> > scattered around?  If the times are all the same, then you should be able
> > to do a simple Union as described here:
> >
> > http://www.unidata.ucar.edu/software/netcdf/ncml/v2.2/Aggregation.html
> >
> > Otherwise, you will need to to a JoinNew, wherein you declare a new
> > dimension as the aggregation dimension.  This is described on the same page.
> >
> > -Lansing
> >
> > > Hi Lansing,
> > >
> > > I think there are group of buoys that are reporting data simultaneously.
> > > The data sets should be overlapping in space.
> > > I included Matt, who is the data officer for this data set, in our
> > > conversation.
> > >
> > > Hi Matt,
> > > Please correct me if the description about the data is not right.
> > >
> > > Thanks a lot,
> > > Li
> > >
> > >
> > > address@hidden> wrote:
> > >
> > > > Li,
> > > >
> > > > Are the data sets from the buoys overlapping in time, space, or both?
> > > >  That is, do you have many buoys that are reporting data
> > simultaneously, or
> > > > are the individual data set series generated by each buoy temporally
> > > > distinct?
> > > >
> > > > Also, are the nc files generated by the buoys, or have they been
> > generated
> > > > through some post-processing from a raw data set?
> > > >
> > > > If the files are not too large, feel free to send me a few
> > representative
> > > > files to work with locally, and I will try to set up an aggregation.
> > > >
> > > > Regards,
> > > >   Lansing Madry
> > > >   Unidata
> > > >   Boulder, Colorado
> > > >
> > > > > Dear Sir,
> > > > >
> > > > > I am trying to reach the experts about NcML aggregation.
> > > > >
> > > > > I have a group of time series buoy nc files. I tried to aggregate
> > them
> > > > > by time, but failed since each of them holds a time series itself.
> > > > >
> > > > > It would be great if anyone could advise me on how should I aggregate
> > > > > these data.
> > > > >
> > > > > Thanks and Regards,
> > > > > Li
> > > > >
> > > > >
> > > >
> > > >
> > > > Ticket Details
> > > > ===================
> > > > Ticket ID: HIP-291542
> > > > Department: Support netCDF Java
> > > > Priority: Normal
> > > > Status: Open
> > > >
> > > >
> > >
> > >
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: HIP-291542
> > Department: Support netCDF Java
> > Priority: Normal
> > Status: Open
> >
> >
> 
> 
> --
> Mathew Biddle, Oceanographer
> NOAA/NODC UMD/ESSIC/CICS E/OC1
> 1315 East-West Hwy
> Silver Spring, MD 20910-3282
> Phone: (301) 713-3272 X163
> Email: address@hidden
> http://www.nodc.noaa.gov/
> http://www.facebook.com/noaa.nodc
> 
> 


Ticket Details
===================
Ticket ID: HIP-291542
Department: Support netCDF Java
Priority: Normal
Status: Open