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[IDV #JNF-919753]: IDV and windspeed and direction grids

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  • Subject: [IDV #JNF-919753]: IDV and windspeed and direction grids
  • Date: Tue, 30 Jul 2013 16:49:55 -0600
> OK Yuan,
> 
> I'm blundering through.  The terms all seem illogical for what you say to
> do, but it is giving results.  Now I find that the meteorological grid from
> the Hurricane Center uses "direction from which" for DIR.  Are there any
> functions or options in IDV to conver this to "direction toward which" the
> ocean convention?
> 
> Murray
> 

IDV is using a alias table to tell if the variable is the wind speed. The 
system default table contains most commonly used variable names for wind speed 
and wind direction. But, in your case, the variable name of speed and direction 
are different and not recognized. This is why you can not get the derived wind 
vector. Hope this explanation make sense.


Yuan
> 
> 
> ----- Original Message -----
> From: "Unidata IDV Support" <address@hidden>
> To: <address@hidden>
> Cc: <address@hidden>
> Sent: Tuesday, July 30, 2013 1:08 PM
> Subject: [IDV #JNF-919753]: IDV and windspeed and direction grids
> 
> 
> >> Hi Yuan,
> >>
> >> No, I really only have SPEED (a scalar) and DIRECTION (a unit vector),
> >> not
> >> special namings of U and V.
> >>
> >> Murray
> >
> > Same procedure, in Cannonical name 2 or 3 should have alias for speed and
> > direction.
> >
> >
> > Yuan
> >>
> >>
> >> ----- Original Message -----
> >> From: "Unidata IDV Support" <address@hidden>
> >> To: <address@hidden>
> >> Cc: <address@hidden>
> >> Sent: Tuesday, July 30, 2013 12:51 PM
> >> Subject: [IDV #JNF-919753]: IDV and windspeed and direction grids
> >>
> >>
> >> >> Yuan,
> >> >>
> >> >> I'm really surprised this morning not to find any wind vector display
> >> >> method
> >> >> for speed and direction grids, only U and V component grids.  Am I
> >> >> missing
> >> >> something, or is there a special addon to do that?
> >> >>
> >> >> Murray
> >> >>
> >> >>
> >> > Murray,
> >> >     It is likely the U and V component in your grids are using some
> >> > special namings and the IDV doesn't recognize them. To make the derived
> >> > wind vector work, you can added the U and V component to the alias
> >> > table.
> >> > In the Field Selector panel, select the variable, right click on the
> >> > selected U(or V), a drop down menu will popup, "add XXX as alias for" >
> >> > Cannonical name 3 > U - U component wind, and the same to the V. After
> >> > that, reload the dataset, and you should see the derived wind vector.
> >> >
> >> >
> >> > Yuan
> >> >
> >> > Ticket Details
> >> > ===================
> >> > Ticket ID: JNF-919753
> >> > Department: Support IDV
> >> > Priority: Normal
> >> > Status: Closed
> >> >
> >>
> >>
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: JNF-919753
> > Department: Support IDV
> > Priority: Normal
> > Status: Closed
> >
> 
> 


Ticket Details
===================
Ticket ID: JNF-919753
Department: Support IDV
Priority: Normal
Status: Closed