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[IDV #RWC-894290]: IDV v2.9u4: Computing surface temperature advection from NAM analysis

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  • Subject: [IDV #RWC-894290]: IDV v2.9u4: Computing surface temperature advection from NAM analysis
  • Date: Mon, 09 May 2011 10:28:23 -0600
> Full Name: Dave Dempsey
> Email Address: address@hidden
> Organization: San Francisco State University
> Package Version: 2.9u4 build date:2011-03-02 08:14 UTC
> Operating System: Mac OS X
> Hardware: Java: home: 
> /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home version: 
> 1.6.0_24 j3d:1.5.2 fcs (build4)
> Description of problem: Creating display: Omni Control
> visad.SetException: visad.SetException: Gridded3DSet.valueToGrid: 
> ManifoldDimension must be 3
> Gridded3DSet.valueToGrid: ManifoldDimension must be 3
> 
> I'm trying to calculate surface temperature advection from the latest NAM 40 
> km analysis, using the Horizontal Advection formula. I specify temperature @ 
> height above ground as my scalar field and u- and v-components of wind 
> @height above ground as the wind components. (The temperature is probably at 
> 2 meters above ground, while the wind components are 10 meters above ground, 
> probably. I wonder if this poses a problem.)
> 
Hi Dave,
   The problem here is the difference in the height, the advection formula in 
the derived does not work in this case.
You can add a local formula to do this:

def surfaceHorizontalAdvection(aFF, uFF, vFF):
    udtdx=GridMath.multiply(GridMath.ddx(aFF),uFF);
    vdtdy=GridMath.multiply(GridMath.ddy(aFF),vFF);
    advgrid=GridMath.add(udtdx,vdtdy);
    return advgrid.negate();

I tested this in my machine and worked. I will probably make some changes in 
the source code, so you will not need to do this in the future.


Yuan

> When I click on the Create Display button, I get the error message above.
> 
 
 
 


Ticket Details
===================
Ticket ID: RWC-894290
Department: Support IDV
Priority: Normal
Status: Open