Re: writing netcdf file along unlimited dimension

• To: Ethan Davis <edavis@xxxxxxxxxxxxxxxx>
• Subject: Re: writing netcdf file along unlimited dimension
• From: John Caron <caron@xxxxxxxxxxxxxxxx>
• Date: Mon, 27 Feb 2006 11:05:37 -0700

The NetcdfFileWriteable.write() signature says:

 /** Write data to the named variable. Must not be in define mode.
  * @param varName name of variable. IllegalArgumentException if variable name 
does not exist.
  * @param origin offset within the variable to start writing.
  * @param values write this array; must be same type and rank as Variable
  * @throws IOException
  */
 public void write(String varName, int [] origin, Array values) throws 
java.io.IOException, InvalidRangeException.

So the problem is it expects that the values array has same rank as variable. 
If it doesnt, i dont think its possible (in general, not in the scalar case) to 
figure out how to write the data. so i will leave it.




Ethan Davis wrote:

I just answered a netcdf-java question about not having to read all data before writing netcdf. I put together some sample code to send them. My first stab was using Arrays with rank 0 but got some out of bounds problems. It does fine if I use an Array of rank 1. Looks like with a rank 0 array the NetcdfFileWriteable.write() calls the N3iosp.writeData() with a sectionList that is empty which then does a get(0) on an empty list.

Probably a pretty quick fix but I haven't thought about it enough to take a stab at it.

Here's my code:

 public void testOne()
 {

   String fileName = "testWriteAlongUnlimited.nc";

NetcdfFileWriteable ncfile = NetcdfFileWriteable.createNew( fileName, true ); Dimension timeDim = new Dimension( "time", Dimension.UNLIMITED.getLength(), true, true, false );

   ncfile.addDimension( null, timeDim );
   Dimension [] dims = { timeDim};
   ncfile.addVariable( "time", DataType.INT, dims );
   ncfile.addVariable( "temp", DataType.FLOAT, dims );
   ncfile.addVariable( "pres", DataType.FLOAT, dims );

   try
   {
     ncfile.create();
   }
   catch ( IOException e )
   {

assertTrue( "Failed to create file <" + fileName + ">: " + e.getMessage(),

                 false);
   }

   ArrayInt.D0 timeArray = new ArrayInt.D0();
   ArrayFloat.D0 tempArray = new ArrayFloat.D0();
   ArrayFloat.D0 presArray = new ArrayFloat.D0();
   for ( int i = 0; i < 10; i++ )
   {
     int[] origin = { i+1};
     timeArray.set( i);
     tempArray.set( i);
     presArray.set( i);
     try
     {
       ncfile.write( "time", origin, timeArray);
       ncfile.write( "temp", origin, tempArray);
       ncfile.write( "pres", origin, presArray);
     }
     catch ( IOException e )
     {

assertTrue( "Failed to write file <" + fileName + "> at index= " + i + ": " + e.getMessage(),

                   false );
     }
     catch ( InvalidRangeException e )
     {

assertTrue( "Bad range writing file <" + fileName + "> at index= " + i + ": " + e.getMessage(),

                   false );
     }
   }
   try
   {
     ncfile.flush();
     ncfile.close();
   }
   catch ( IOException e )
   {

assertTrue( "Failed to flush/close file <" + fileName + ">: " + e.getMessage(),

                 false );
   }
 }