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Lat/Lon to Polar: Revisited

Greetings,
With all these great examples of dynamic map projections, it reminded me of something I tried a couple of years ago. I have several netCDF terrain files that are read into VisAD as ((Longitude, Latitude) -> Altitude). I have an EarthLocationTuple (radar site) that is located in the (lat/lon) center of each terrain file. 
I can use Radar"X"DCoordinateSystem to get an az/ran for each lat/lon 
gridpoint of my terrain file.  I would like to create a corresponding 
set of ((Range, Azimuth)->Altitude) netCDF files for each of the 
original terrain files.  Doing this would hopefully speed up many 
calculations - or at least simplfy my code by eliminating the lat/lon -> 
az/ran conversion.

My problem is that I don't know how to construct the data set so that 
VisAD can read/plot the az/ran data.  I am unsure whether to try to 
create the domain [either (Range, Azimuth) or (Azimuth, Range)] as a 
Gridded2DSet, Irregular2DSet, or what.  I have tried both.  The 
Gridded2DSet fails saying that I do not have a valid grid (apparently 
when azimuth goes from 359  -> 0 degrees).  The Irregular2DSet takes way 
to long and runs out of heap space (even when I set it to 512 Mb).  So I 
guess my main question is how do I construct my domain set to be a valid 
grid composed of radar-centric polar coordinates - if it is even possible?

Also, I assume that I would set my ScalarMaps to Display.Radius (Range) 
and Display.Longitude (Azimuth), but do I set my RealTypes (Range and 
Azimuth) to RealType.Radius and RealType.Longitude also?

Thanks so much for any insight anyone can provide!

-kevin.

--
+------------------------------------------------------------+
Kevin L. Manross        [KD5MYD] <><          (405)-366-0557
CIMMS Research Associate               kevin.manross@xxxxxxxx
[NSSL-WRDD/SWATN]           http://www.cimms.ou.edu/~kmanross

"My opinions are my own and not representative of CIMMS, NSSL,
NOAA or any affiliates"
+------------------------------------------------------------+







   
  
   






   
 
   

    
    
     
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