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[GEMPAK #UQC-142063]: gridded data lat/lon

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  • Subject: [GEMPAK #UQC-142063]: gridded data lat/lon
  • Date: Thu, 25 Oct 2012 13:25:52 -0600
Hi Evi,

Reading latitude and longitude can be easily done with GFUNC special parameters 
LATR and LONR, in radians, which can be converted to degrees with:

GFUNC = mul(latr,RTD) for latitude listed for row/column number
GFUNC = mul(lonr,RTD) for longitude

Hope this is what you need to make it work.

Michael
Unidata



> 
> Dear Sir/Madam
> 
> I need to get text data of my interpolated field with Barnes algorithm
> at each point. In addition, I need to have (confirm) the latitude and
> longitude of each grid point. I am using mercator projection.
> 
> So far, the first problem is solved using GDLIST which shows me ROWS
> and COLUMNS of the interpolated variable in my grid and then I save it
> to file.
> 
> The second problem is a bit more difficult since GEMPAK does not seem to
> have a function to extract the latitude and longitude of a particular
> grid point. Say if I wanted to know the LAT LON of point (10,3) GEMPAK
> can only give me data values and the time stamp but not LON and LAT.
> 
> If the projection is mercator can I assume that increments in longitude
> and latitude are constant when I created the grid with OAGRID? In my
> case, when I constructed the grid I used DELTAX=0.03 and DELTAY=0.03
> and specified the LON and LAT values of the lower left and upper right
> corners. If the above assumption about the projection is correct then
> there is no need to ask GEMPAK.
> 
> Thank you very much for your time enad help
> 
> Sincerely,
> 
> Evi Becerra
> 
> 
> 

Ticket Details
===================
Ticket ID: UQC-142063
Department: Support GEMPAK
Priority: Normal
Status: Open