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> Full Name: Stefan Cecelski > Email Address: address@hidden > Organization: University of Maryland > Package Version: 3.0b2 build date:2011-07-20 07:08 UTC > Operating System: Mac OS X > Hardware: Java: home: > /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home version: > 1.6.0_26 j3d:1.5.2 fcs (build4) > Description of problem: There was an error loading the data: > Error creating data source:file.grads with: > /Volumes/WD/data/ERA/sfc/ERA_surface.ctl > Grid data source failed making data set: > /Volumes/WD/data/ERA/sfc/ERA_surface.ctl > Cant read /Volumes/WD/data/ERA/sfc/ERA_surface.ctl: not a valid CDM file. > > I have used gribmap/ungrib/ect. in GrADS to make a .ctl/.idx pair for loading > up all of my ERA-Interim grib data files so I don't have to open them one a > time since they are separated into 6 hour time steps. Basically, the .ctl > file points to the .idx file which holds the information to make the separate > data files seem as one large data file. When I try to load the .ctl file in > grads, this is the error I get. > > If there is a simpler way to 'merge' the data using IDV(and not the forumula > for merging time steps) so I can easily access all the timesteps as they were > one single file, I would be willing to go that route as well. Thanks in > advance. > > V/R, > > Stefan Hi Stefan, Sorry for the delay response since I don't have much knowledge of GrADS data. I think if individual file can be loaded into the IDV as grid data type, you can try to use the Aggregate data source type instead of doing the merging in the .ctl file. Please let us know if this doesn't help. Yuan > > ****************** > Stack trace: > java.io.IOException: Cant read /Volumes/WD/data/ERA/sfc/ERA_surface.ctl: not > a valid CDM file. > at ucar.nc2.NetcdfFile.open(NetcdfFile.java:744) > at ucar.nc2.NetcdfFile.open(NetcdfFile.java:394) > at ucar.nc2.dataset.NetcdfDataset.openOrAcquireFile(NetcdfDataset.java:687) > at ucar.nc2.dataset.NetcdfDataset.openDataset(NetcdfDataset.java:424) > at ucar.nc2.dataset.NetcdfDataset.acquireDataset(NetcdfDataset.java:520) > at ucar.nc2.dt.grid.GridDataset.open(GridDataset.java:103) > at ucar.nc2.dt.grid.GridDataset.open(GridDataset.java:89) > at > ucar.unidata.data.grid.GeoGridDataSource.doMakeDataSet(GeoGridDataSource.java:1094) > at > ucar.unidata.data.grid.GeoGridDataSource.getDataset(GeoGridDataSource.java:1116) > at > ucar.unidata.data.grid.GeoGridDataSource.initAfterCreation(GeoGridDataSource.java:478) > at ucar.unidata.data.DataManager.createDataSource(DataManager.java:1553) > at > ucar.unidata.idv.IntegratedDataViewer.createDataSource(IntegratedDataViewer.java:1998) > at > ucar.unidata.idv.IntegratedDataViewer.makeDataSource(IntegratedDataViewer.java:1915) > at > ucar.unidata.idv.IntegratedDataViewer.makeDataSource(IntegratedDataViewer.java:1849) > at > ucar.unidata.idv.IntegratedDataViewer.makeDataSource(IntegratedDataViewer.java:1822) > at ucar.unidata.idv.chooser.IdvChooser.makeDataSource(IdvChooser.java:943) > at ucar.unidata.idv.chooser.FileChooser.selectFilesInner(FileChooser.java:656) > at ucar.unidata.idv.chooser.FileChooser.selectFiles(FileChooser.java:525) > at ucar.unidata.idv.chooser.FileChooser.doLoadInThread(FileChooser.java:547) > at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) > at > sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) > at > sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) > at java.lang.reflect.Method.invoke(Method.java:597) > at ucar.unidata.util.Misc$2.run(Misc.java:1063) > at ucar.unidata.util.Misc$3.run(Misc.java:1091) > > > Ticket Details =================== Ticket ID: XYY-917880 Department: Support IDV Priority: Normal Status: Closed