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20000720: vertical interpolation and map projections

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  • Subject: 20000720: vertical interpolation and map projections
  • Date: Thu, 20 Jul 2000 15:22:44 -0600

Brian,

I provided the gdbiint program to interpolate from one grid projection
to another.

You can use gdvint to interpolate...with GVCORD   = pres/pres
to interpolate to the same output coordinate.

Attatched is the README I provided in Patch 6 for gdbiint. This program
is in the current patched distribution under teh $NAWIPS/unidata/programs
directory.

Steve Chiswell
Unidata User Support


On Thu, 20 Jul 2000, Darrell Bryan Ensley wrote:

> 
> Hi, Gembudders,
> 
> I have ECMWF gridded data in a CED (Cylindrical Equidistant)
> map projection, with standard pressure levels (1000,925,850,
> etc). I need these grids in STR (polar stereographic) with 
> grids every 50 mb, from say 1000 mb to 50 mb).
> 
> 1) Does GEMPAK have the capability to transform map projections 
>    (ie, CED to STR)? 
> 2) Can GEMPAK vertically interpolate data using the same GVCORD?
>    
> Thanks in advance!
> 
> Darrell
> 
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Darrell Bryan Ensley         <address@hidden>      
> Mesoscale Dynamics Lab          5703 Windlestraw Dr.
> Rm 135, Research III            Apartment 37
> North Carolina State Univ.      Durham, NC 27713
> W: (919) 515-1437               H: (919) 361-1346  
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> 
> 



To install this program, download the tar file and place in your
$NAWIPS directory then extract the contents with:
zcat gdbiint.tar.Z | tar xvf -

To build the program:
cd $NAWIPS/unidata/programs/gdbiint
make clean
make all
make install
make clean


To use the program, first create the output file with the
desired projection using GDCFIL. Then run GDBIINT with GDFILE 
as your input grid file, and GDOUTF the grid file created in GDCFIL.

The program will first generate an interpolation array for
the location of the output grid points within the input
grid domain. This step can take a while depending on
how big the grid sizes are (but it is only done once-
so be patient while this is done). Then, for each
grid in the input grid file, the grid points are
interpolated to the output grid and written out to
the GDOUTF.