Re: newbie, netCDF/isocontour/SpreadSheet ?'s.

• To: visad-list@xxxxxxxxxxxxx
• Subject: Re: newbie, netCDF/isocontour/SpreadSheet ?'s.
• From: "From: Bill Hibbard <hibbard@xxxxxxxxxxxxxxxxx>" <billh@xxxxxxxxxxxxx>
• Date: Tue, 8 Jun 1999 17:10:21 -0500 (CDT)

Hi Roland,
 
> ... I don't see anything displayed in interior of the box.
 
I am taking the week off, and will be at JavaOne next week, so cannot
just load your data file into the SpreadSheet and figure out why you
don't see anything.  Perhaps one of the other VisAD folks can figure
it out.  I'd take a look at the MathType in the SpreadSheet's Edit
Mappings window, and also use Tom Whittaker's
 
  visad.jmet.DumpType ball50.nc
 
to make sure that the Field domain Sets are not trivial.  I'd also try
changing the default mappings in the SpreadSheet, say replacing IsoContour
by RGB.
 
> If I'm guessing correctly, valid range is used for the
> slider that selects the isocontour value.
 
Actually, the range of values for the IsoContour slider is the actual
range of values of the RealType mapped to IsoContour, as computed by
VisAD.  If you write an application, you can override this range by
calling the setRange() method of the ScalarMap to IsoContour.
 
> The second thing I noticed has to do with translation of
> the time coordinate.
 
There has been lots of work lately on VisAD dates and times, which are
represented by double precision seconds since 1970-01-01 00:00:00Z.
I'll leave it to Steve to explain how time Units in netCDF files are
imported into VisAD.
 
One other point.  You always have the option of writing a custom VisAD
data importer for netCDF for packed data.  The JMet package does this
simply for efficiency.  If you can assume a particular file organization
it is much easier than writing a general netCDF importer.
 
Cheers,
Bill
----------------------------------------------------------
Bill Hibbard, SSEC, 1225 W. Dayton St., Madison, WI  53706
hibbard@xxxxxxxxxxxxxxxxx  608-263-4427  fax: 608-263-6738
http://www.ssec.wisc.edu/~billh/vis.html