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[IDV #TYB-719779]: Support request

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  • Subject: [IDV #TYB-719779]: Support request
  • Date: Wed, 19 Nov 2008 16:30:32 -0700
Hi Mohit-

> I guess, produced wind vector flow is not in the form of grid. I tried to
> use dirn(Vector) formula using driv jython method. In the formula editor
> used dirn(Vector) for calling the formula. I had impression that the
> formula will convert wind flow vector into wind azimuth (angle) grid. The
> issue is need to assign wind flow vector as an input in the field selector
> window. Unfortunetly, produced wind flow vector is not appearing into the
> field selctor window. I would request you to test the attached data
> (previous mail) for producing the wind azimuth angle grid. I would also
> request you to kindly explain me the steps for the same.

You can create the vector from the u and v using the vecr Jython procedure
or by using the "Grid->Make flow vectors from grid relative u and v data" 
formula.

You can use the Grid->Create Grid Diagnostic formula and in the
dialog, use  dirn(vecr(u,v)).  You will then be prompted for the
u and v variables and can select your u and v grids at that point.
Or you could create a new formula to hold dirn(vecr(u,v)) so you can
call it over and over.

Don Murray
> On Wed, Nov 19, 2008 at 8:10 PM, Mohit Kalra <address@hidden> wrote:
> 
> > Dear Don,
> >
> > Thanks for your quick reply. Though, i'm using IDV but not familiar with
> > all the functions. So, i would be thankful, if you could explain me steps
> > for using dirn or dirv Jython methods in the griddiag.py. Further, i
> > enclosed wind data in netCDF format for your consideration (U and V
> > component at 850mb pressure level with geopotential height). I'm interested
> > in producing the raster grid with the wind angle value from 0 to 360 degree.
> >
> >
> > Waiting for your reply.
> >
> > Thanks and regards,
> >
> > Mohit
> >
> >
> >
> > ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
> >
> >
> >
> >
> > address@hidden> wrote:
> >
> >> Hi Mohit-
> >>
> >> This is Don.
> >>
> >> > Thanks for your reply. I have another question regarding wind vector
> >> flow
> >> > estimation using IDV. I have calculated wind speed and flow vector using
> >> U,
> >> > V and W component of wind. I am wondering if the flow vector could be
> >> use
> >> > for getting the wind azimuth angle from 0 to 360 degree.
> >> >
> >> > Looking forward to hear from you.
> >> >
> >> > Thanks and regards,
> >>
> >> You can calculate the direction using the dirn or dirv Jython
> >> methods in the griddiag.py.  dirn will return the true north
> >> direction, dirv will return the grid relative direction (if
> >> you have a grid relative vector).  You would call this with
> >>
> >> dirn(vector)
> >>
> >> where vector is the flow vector grid.
> >>
> >> Don Murray
> >>
> >> Ticket Details
> >> ===================
> >> Ticket ID: TYB-719779
> >> Department: Support IDV
> >> Priority: High
> >> Status: Open
> >>
> >>
> >
> 
> 


Ticket Details
===================
Ticket ID: TYB-719779
Department: Support IDV
Priority: High
Status: Open