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[IDV #ECG-920998]: get wind direction from grid sources

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  • Subject: [IDV #ECG-920998]: get wind direction from grid sources
  • Date: Mon, 30 Nov 2009 10:31:37 -0700
Hi-

> Full Name: Nguyen Duc Ha
> Email Address: address@hidden
> Organization: ITC
> Package Version: 2.8a1 build date:2009-11-29 08:08 UTC
> 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!
> I am trying to get wind direction at location and time from grid sources by 
> this way:
> 
> u = sampletoReal ( u_component grid of wind, EarthLocation, animationValue)
> v = sampletoReal ( v_component grid of wind, EarthLocation, animationValue)
> 
> and then I do :
> direction = dirr(vecr(u,v))
> however I got this error: "1st arg can't be coerced to visad.FieldImpl"
> 
> Could you tell me what should I do here?

The dirr only works with grids, not single points.  Your best bet would be to
create the dirr grid and then sample that. 

Don Murray

Ticket Details
===================
Ticket ID: ECG-920998
Department: Support IDV
Priority: Normal
Status: Open