Re: [netCDFJava #UUN-799950]: "Unable to find center point variables" problem

Rich-

This falls into the general category of the problems of how the
IDV handles the dimensionless vertical coordinate.  I have no
solution for this problem that would allow accurate interpretation
of the data.  If we ignore the non-griddedness of the data, then
any resampling or interpolation of the data is apt to be faulty.

Sorry.

Don

Rich Signell wrote:
> John,
>
> Sheesh!   Yes, adding "CF-1.0" attribute got rid of that problem, and
> now when I try an isosurface of temperature on
>
> http://stellwagen.er.usgs.gov/models/test/ecom_test.ncml
>
> I have the old "samples do not form a valid grid" again.   But at
> least that makes sense, as this NCML version should function the same
> was as the NetCDF file that I modified.   You guys are still trying to
> figure this one out, right?
>
> Visad.SetException: Gridded3DSet: samples do not form a valid grid (66,0,0)
>         at visad.Gridded3DSet.<init>(Gridded3DSet.java:327)
>         at visad.GriddedSet.create(GriddedSet.java:218)
>         at visad.GriddedSet.create(GriddedSet.java:130)
>         at 
> visad.EmpiricalCoordinateSystem.ensureNoCoordinateSystem(EmpiricalCoordinateSystem.java:108)
>         at 
> visad.EmpiricalCoordinateSystem.<init>(EmpiricalCoordinateSystem.java:81)
>         at 
> ucar.unidata.data.grid.GeoGridAdapter.makeDomainWithVerticalTransform(GeoGridAdapter.java:940)
>         at 
> ucar.unidata.data.grid.GeoGridAdapter.getSpatialDomainSet(GeoGridAdapter.java:419)
>         at 
> ucar.unidata.data.grid.GeoGridAdapter.getFlatField(GeoGridAdapter.java:1054)
>         at 
> ucar.unidata.data.grid.GeoGridAdapter.makeSequence(GeoGridAdapter.java:1211)
>         at 
> ucar.unidata.data.grid.GeoGridAdapter.getSequence(GeoGridAdapter.java:997)
>         at 
> ucar.unidata.data.grid.GeoGridDataSource.makeFieldImpl(GeoGridDataSource.java:1418)
>         at 
> ucar.unidata.data.grid.GeoGridDataSource.getDataInner(GeoGridDataSource.java:1134)
>         at ucar.unidata.data.DataSourceImpl.getData(DataSourceImpl.java:2043)
>         at ucar.unidata.data.DirectDataChoice.getData(DirectDataChoice.java:333)
>         at ucar.unidata.data.DataChoice.getData(DataChoice.java:618)
>         at ucar.unidata.data.DataInstance.getData(DataInstance.java:239)
>         at ucar.unidata.data.DataInstance.getData(DataInstance.java:203)
>         at 
> ucar.unidata.data.grid.GridDataInstance.init(GridDataInstance.java:204)
>         at 
> ucar.unidata.data.grid.GridDataInstance.<init>(GridDataInstance.java:161)
>         at 
> ucar.unidata.data.grid.GridDataInstance.<init>(GridDataInstance.java:142)
>         at 
> ucar.unidata.idv.control.GridDisplayControl.doMakeDataInstance(GridDisplayControl.java:241)
>         at 
> ucar.unidata.idv.control.DisplayControlImpl.initializeDataInstance(DisplayControlImpl.java:2875)
>         at 
> ucar.unidata.idv.control.DisplayControlImpl.setData(DisplayControlImpl.java:2857)
>         at 
> ucar.unidata.idv.control.ThreeDSurfaceControl.setData(ThreeDSurfaceControl.java:250)
>         at 
> ucar.unidata.idv.control.ThreeDSurfaceControl.init(ThreeDSurfaceControl.java:156)
>         at 
> ucar.unidata.idv.control.DisplayControlImpl.init(DisplayControlImpl.java:1229)
>         at 
> ucar.unidata.idv.control.DisplayControlImpl.init(DisplayControlImpl.java:967)
>         at 
> ucar.unidata.idv.ControlDescriptor.initControl(ControlDescriptor.java:948)
>         at ucar.unidata.idv.ControlDescriptor$1.run(ControlDescriptor.java:875)
>         at ucar.unidata.util.Misc$3.run(Misc.java:1011)
>
> Thanks,
> -Rich
>
> On Jan 8, 2008 7:02 PM, Unidata netCDF Java Support
> <address@hidden> wrote:
> > > John,
> > >
> > > I think Don Murray passed this along, but the e-mail trail was quite
> > > confusing, so here's the original question again, which still stands:
> > >
> > > I have a NCML file that attempts to "CF-ize" a non-conforming NetCDF file:
> > >
> > > http://stellwagen.er.usgs.gov/models/test/ecom_test.ncml
> > >
> > > If I open this file in IDV 2.4, I can view the 2D fields like
> > > "heat_flux" just fine, but when I try an isosurface of a 3D field like
> > > "temp", I get the Error:
> > >
> > > "Couldn't get data
> > > Unable to find center point variables"
> > >
> > > I haven't seen this error before.   Any ideas?
> > >
> > > Thanks,
> > > Rich
> > >
> > > --
> > > Dr. Richard P. Signell   (508) 457-2229
> > > USGS, 384 Woods Hole Rd.
> > > Woods Hole, MA 02543-1598
> > try adding the conventions attribute:
> >
> > <netcdf xmlns="http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2";>
> >   <aggregation type="union">
> >     <netcdf location="./ecom_lonlat.nc" />
> >     <netcdf location="./ecom_test.cdf">
> >       <variable name="temp">
> >         <attribute name="coordinates" type="String" value="lon lat sigma" />
> >       </variable>
> >       <variable name="sigma">
> >         <attribute name="standard_name" type="String" 
> > value="ocean_sigma_coordinate" />
> >         <attribute name="formula_terms" type="String" value="sigma: sigma eta: elev 
> > depth: depth" />
> >         <attribute name="positive" type="String" value="up" />
> >         <attribute name="units" type="String" value="1" />
> >       </variable>
> >       <attribute name="Conventions" value="CF-1.0"/>
> >     </netcdf>
> >   </aggregation>
> > </netcdf>
> >
> > Ticket Details
> > ===================
> > Ticket ID: UUN-799950
> > Department: Support netCDF Java
> > Priority: Normal
> > Status: Closed

--
*************************************************************
Don Murray                               UCAR Unidata Program
address@hidden                        P.O. Box 3000
(303) 497-8628                              Boulder, CO 80307
http://www.unidata.ucar.edu/staff/donm
*************************************************************