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Re: NetCDF java lib

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  • Subject: Re: NetCDF java lib
  • Date: Wed, 02 Nov 2005 09:47:03 -0700
James Harle wrote:


Dear John,
I've been trying to use your NetCDF Java Library to read and sub- sample netcdf files and netcdf datasets into the latest version of Matlab, which I had success at. I've also been trying to read in HDF5 files, but to no avail. When I try and open the file I get the following: 

 nc = NetcdfFile.open(filename);
??? Java exception occurred:
java.lang.NoClassDefFoundError
        at ucar.nc2.H5header.addSystemAttributes(H5header.java:2000)
        at ucar.nc2.H5header.makeVariable(H5header.java:1985)
        at ucar.nc2.H5header.makeNetcdfGroup(H5header.java:1774)
        at ucar.nc2.H5header.readSuperBlock(H5header.java:200)
        at ucar.nc2.H5header.read(H5header.java:120)
        at ucar.nc2.H5iosp.open(H5iosp.java:76)
        at ucar.nc2.NetcdfFile.<init>(NetcdfFile.java:754)
        at ucar.nc2.NetcdfFile.open(NetcdfFile.java:334)
        at ucar.nc2.NetcdfFile.open(NetcdfFile.java:219)
        at ucar.nc2.NetcdfFile.open(NetcdfFile.java:165)
        at ucar.nc2.NetcdfFile.open(NetcdfFile.java:149).
when I import ucar.nc2.H5header and look at the methods available I only have the follow: 

Methods for class ucar.nc2.H5header:
close getClass notify setDebugOutputStream wait equals hashCode notifyAll toString
I am using toolsUI-2.2.10.jar, I no pretty much nothing about Java - apart from it's taking a while for my head to get a handle on this object oriented stuff. Could you tell me whether I am doing the right thing (if you can from the limited info I have provided), or am I using the wrong *.jar, or may be some HDF5 files just can't be read?
1. im guessing a classpath problem, perhaps some classes or jars that are interfering? do you have other jars or classes in your classpath?
2. Look in toolsUI-2.2.10.jar and make sure that ucar.nc2.units.DateUnit is in the jar. 

3. Download a new copy of toolsUI-2.2.10.jar in case it got damaged.
4. otherwise, see if you can create a small program that recreates the problem and send it to me.