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[IDV #XCQ-975623]: plotting a global grib data set

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  • Subject: [IDV #XCQ-975623]: plotting a global grib data set
  • Date: Wed, 11 Nov 2009 14:59:44 -0700
Hi HP-

Sorry for the delay in responding.

> Full Name: HansPeter Roesli
> Email Address: address@hidden
> Organization: EUMETSAT
> Package Version: 2.8a1 build date:@DATE@
> Operating System: Windows Vista
> Hardware: Java: home: C:\Program Files\IDV_2.8a1\jre version: 1.6.0_13 
> j3d:1.5.2 fcs (build4)
> Description of problem: Hi
> 
> There are 2 issues with the attached grib file, a *global* TOZ field by ECMWF.
> 
> 1. The data cannot be spatially subset across the 0? longitude. I remember we 
> have had this issue quite some time ago (and solved it for limited-area 
> data). Probably this was never checked for files containing global data sets.

You are correct that you cannot subset across the projection boundary.  This 
will require a change to the underlying netCDF library.  It has to convert a 
lat/lon box into index space and that would require some work to get the 
indices right.  It's on the list of things to do, but is not an easy task.

> 2. Contour plan view of the global field works fine. However, the 
> colour-filled view remains blank and the colour-shaded view is flat and only 
> shows the filed over the Antarctica.

If you are not displaying in the native projection, you'll need to turn off 
Fast Rendering so the projection seams can be accounted for.  If you display in 
the data projection, things should display correctly.

Don Murray

Ticket Details
===================
Ticket ID: XCQ-975623
Department: Support IDV
Priority: Normal
Status: Open