Regrid2 output grid

[Remi Meynadier]

Hi,

I am using regrid2 function and i am not completly sure how this function works.
I don't really understand how X(I) and Y(J) (see below extract from
regrid2.doc) are computed.
Where can i find this fields and the output grid ? I've looked in
udf.regrid.out but not sure to fully understand.
And i would like to know how the nearest neighbor grid point points are
choosen before bilinear interpolation ?

Thanks in advance,

Remi Meynadier

Extract from regrid2.doc:
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METHODOLOGY:

The first step in the regrid transform is to define a
relationship between the input and output grids within a common
frame of reference or coordinate system.  regrid bases the
inter-grid relationship on "world" coordinates, and the GrADS map
between grid coordinates (i,j) and world coordinates (lon, lat).
As noted above, the world-grid mapping in GrADS is
one-dimensional.  Thus, the world-grid map of an input GrADS grid
takes the form,

   lat(i,j)=f(j) and lon(i,j)=g(i).

By specifying a similar mapping for an output GrADS grid of the
form

   LAT(I,J)=F(J) and LON(I,J)=G(I),

as defined by the input parameters X1, X2 and X3-6, regrid
calculates,

   X(I)=i(G(I)) and Y(J)=j(F(J)),

where i(G(I)) is the location of the output grid with respect to
the input grid dimension i and j(F(J)) for j.

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