[IDV #CLG-761846]: Re: [idvusers] Problem using NARR-A as aggregated GRIB files in IDV

["Unidata IDV Support" <support-idv@xxxxxxxxxxxxxxxx>]

Hi Jay-

> Full Name: Jason Shafer
> Email Address: jason.shafer@xxxxxxxxxxxxxxx
> Organization: Lyndon State College
> Package Version: 2.4 build date:2007-12-20 16:34 UTC
> Operating System: Linux
> Hardware: Java: home: /software/idv/IDV_2.4/jre version: 1.5.0_11 j3d:1.3.1
> Description of problem: Hi,
> 
> I'm having problems aggregating the NARR Reanalysis data. IDV does not seem to be
> capable of loading multiple times and aggregating the files. I noticed your solution in a
> previous post below, but couldn't get the solution to work. I think this might have been
> due to this link being dead: http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2%22

No, that's just an XML namespace pointer.  It can be anything (e.g. http://foo.bar)
and doesn't have to be a valid link.

For the NcML solution I provided Ryan, you need to be running version 2.5 
instead of 2.4.  Try downloading the latest version and use the NcML
solution.

> I was wondering if a solution exists currently, and if not when a solution might exist.

I'm in the process of testing the next version which should handle
this out of the box, but that probably won't be publicly available 
until next month (July).

> Thanks for your time.

Let me know if the NcML doesn't work with version 2.5.

Don Murray

> 
> * To: rboller@xxxxxxxxxxxx
> * Subject: [IDV #CLG-761846]: Re: [idvusers] Problem using NARR-A as aggregated GRIB files in IDV
> * From: "Unidata IDV Support" <support-idv@xxxxxxxxxxxxxxxx>
> * Date: Wed, 05 Mar 2008 09:26:41 -0700
> * Delivered-to: support-idv@xxxxxxxxxxxxxxxx by laraine.unidata.ucar.edu (Postfix) with ESMTP id 89BB7CB189; Wed, 5 Mar 2008 09:26:41 -0700 (MST) id 618DFD5116; Wed, 5 Mar 2008 09:26:41 -0700 (MST)
> 
> Hi Ryan-
> 
> Sorry for the delay in responding.  I've been out for the past few
> weeks.
> 
> > I seem to have come across the same problem as I've found on the message
> > board (see below).  While I could use the "Make a time sequence" formula,
> > this quickly becomes old when 20+ files are involved.  I'm using NCEP model
> > data and have similar time tag issues... i.e.,
> >
> > The "fnl_060913_00_00" file:
> >
> > :_CoordinateModelRunDate = "2006-09-13T00:00:00Z"
> > int time(time=1);
> > :long_name = "forecast time";
> > :units = "hour since 2006-09-13T00:00:00Z";
> > :GRIB_orgReferenceTime = "2006-09-13T00:00:00Z";
> > :GRIB2_significanceOfRTName = "Start of forecast";
> > :_CoordinateAxisType = "Time";
> >
> >
> > The "fnl_060913_06_00" file:
> > :_CoordinateModelRunDate = "2006-09-13T06:00:00Z";
> > int time(time=1);
> > :long_name = "forecast time";
> > :units = "hour since 2006-09-13T06:00:00Z";
> > :GRIB_orgReferenceTime = "2006-09-13T06:00:00Z";
> > :GRIB2_significanceOfRTName = "Start of forecast";
> > :_CoordinateAxisType = "Time";
> >
> >
> > I'm thinking that the easiest workaround would be to write a script to make
> > all of the model run times to be the same while varying the
> > orgReferenceTime.  Is this appropriate?   I'm open to tweaking the IDV code
> > if that makes more sense.
> 
> The issue is down in the netCDF Java code and a fix is being worked on
> for the next version.  But that release is several months away.  However,
> in the mean time, you might be able to use NcML to solve your problem.
> Here's an example that works with the IDV (open it using I'm Feeling Lucky
> or with the Grib files Data Source Type):
> 
> <netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2";;>
> <variable name="time" shape="time" type="int">
> <attribute name="units" value="hour since 2006-09-13T00:00:00Z"/>
> <attribute name="_CoordinateAxisType" value="Time" />
> <values start="0" increment="6" />
> </variable>
> <aggregation type="joinExisting" dimName="time">
> <netcdf location="fnl_060913_00_00"/>
> <netcdf location="fnl_060913_06_00"/>
> <netcdf location="fnl_060913_12_00"/>
> </aggregation>
> </netcdf>
> 
> basically, you define the time variable and it's values, then use
> the aggregation tag to list the files you want to aggregate.
> 
> Save this in a text file with the extension .ncml (eg. ryan.ncml)
> and place it in the same directory as the files.   Alternatively,
> you can specify the full path name to the file like:
> 
> <netcdf location="file:/C:/data/grids/fnl_060913_00_00">
> 
> > Thanks much for any suggestions.
> 
> Let me know if that doesn't work for you.  I tested this with
> version 2.5b1 (nightly build).
> 
> Don
> 
> > -----
> >
> > Hi Tim-
> >
> > Tim Axelrod wrote:
> > > I'd like to be able to use a set of NARR-A grb files as a data source to
> > > IDV and be able to display them as an animation and/or use the data
> > > probe/time series tool. I'm able to do this with NAM grb files by
> > > selecting "aggregated GRIB files" as the data source type. This fails
> > > with the NARR-A grb files, however. Only a single time gets shown in the
> > > field selector/times window - and that time seems to be randomly selected
> > > from the set of files.
> >
> > This is not possible at present but a solution is being worked on
> > in the underlying netCDF-Java layer. But that won't be available
> > for a few months.
> >
> > The NAM works because they all have the same model run time and each
> > file has an offset forecast hour. Each NARR file has a different
> > base ("model run") time with a forecast hour of 0, so the aggregation
> > doesn't know what to use as a "model run" time.
> >
> > > I'm using IDV 2.3, build data 2007-08-15. Any advice?
> >
> > If you are daring, you could run the nightly build which has
> > formula in it for making a time sequence from a set of single time
> > images or grids. What you would do is select all the NARR files you
> > want to "aggregate" and use the I'm Feeling lucky option in the
> > Files Chooser. Then use the "Miscellaneous->Make a time sequence from
> > single time grids/images" formula. That will pop up a dialog that
> > allows you to select the individual grids. This will be time consuming
> > if you have a lot of files. It's a a new feature (multiple parameter
> > selection), so feedback is welcome.
> >
> > The nightly build is available at:
> >
> > http://www.unidata.ucar.edu/software/idv/release/nightly
> >
> > Don Murray
> > *************************************************************
> > Don Murray UCAR Unidata Program
> > dmurray@hidden_host P.O. Box 3000
> > (303) 497-8628 Boulder, CO 80307
> > http://www.unidata.ucar.edu/staff/donm
> > *************************************************************
> >
> >
> 
> 
> Ticket Details
> ===================
> Ticket ID: CLG-761846
> Department: Support IDV
> Priority: Normal
> Status: Open
> 
> 
> 
> 


Ticket Details
===================
Ticket ID: CLG-761846
Department: Support IDV
Priority: Normal
Status: Open