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[IDV #RCR-783387]: Odd grid data generation behavior...

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  • Subject: [IDV #RCR-783387]: Odd grid data generation behavior...
  • Date: Sat, 24 Jan 2009 14:49:54 -0700
Hi Tom-

> I've discovered something weird with GeoGridDataSource:
> 
> Sometimes the domain of the adapted FlatField is a Linear2DSet,
> sometimes it's a Gridded2DSet.  The data has a projection, in this
> VerticalPerspective, so I'm at a loss to understand why a GriddedSet
> is needed *sometimes*.  In fact, a GriddedSet is only used when
> a stride is applied, and even then, not all of the time.  This is a
> potential performance hit for NetCDF files that have large dimensioned
> grids.

That's all handled down in GeoGridAdapter.  Maybe the striding is
screwing up the determination of linearity?  If you run the 
IDV with -debug, you'll get some printouts from GeoGridAdapter
on what it has determined is needed.  If you can give some examples,
I can look further.  A linear set is used if it can determine that
the coordinate axes are linear and the Z dimension is > 1 (if there
is a Z coordinate).  Single level grids (3D on 2D manifold) have to
be GriddedSets or we get weird displays.

Don

Ticket Details
===================
Ticket ID: RCR-783387
Department: Support IDV
Priority: Normal
Status: Open