Re: [ferret_users] scat2gridgauss not functioning properly

[jaison@xxxxxxxxxxxxxx]

Hi Steve,
           According to documentation (and from experience), the first two
input arguments to SCAT2GRIDGAUSS function should be defined on either X
(and ZT) or Y (and ZT) axis, but NOT on both X and Y at the same time.
(see  Ch3 Sec2.3.37.  SCAT2GRIDGAUSS_XY). In your script add the following
lines

   let xx1D = XSEQUENCE(xx)
   let yy1D = XSEQUENCE(yy)

then use these variables in SCAT2GRIDGAUSS function as

   let sgrid = scat2gridgauss_xy(xx1D, yy1D, .........)

Ok. The last argument (9th one) is not used in newer versions of Ferret.
The 3 arguments before that, XSCALE, YSCALE and CUTOFF need to be chosen
to match your destination grid. Read the documentation carefully for
CUTOFF. You can try few different values to choose between high-data loss
(smaller SCALE and CUTOFF) and high-smoothing (higher SCALE and CUTOFF),
with respect to the destination grid. For example, if CUTOFF is 2, then
XSCALE can be dx (of destination grid) and YSCALE can be dy.

Also note that, it is always a good habit to add proper units while
defining axis, and use proper names (xlon, ylat or xkm, ykm etc).

Please let me  know if you have any questions.

Thanks and Regards,

Jaison

> Hello Ferreters,
>
> I am trying to put scattered data onto a regular grid and tried with the scat2gridgauss
> function.
>
> Here is my code:
>
> ! the scattered data axes...
> def axis/x=1:960:1 x;def axis/y=1:367:1 y;def grid/x=x/y=y g
> file/format=stream/grid=g/var="xx,yy,zz,dbz" output.dat
> ! the regular grid axes...
> def axis/x=-240:240:0.5 nx;def axis/y=-240:240:0.5 ny
> let sgrid = scat2gridgauss_xy(xx, yy, dbz, x[gx=nx], y[gy=ny], 2.,2.,2.,0)
>
> The result does not work (toying with the last few parameters makes no difference),
> although it does have the grid I expect.  I'm assuming the same will be true for the
> scat2gridlaplace functions as well.
>
> Any ideas?
>
> Thanks,
> Steve
>
>
> =======================================================
> Stephen R. Guimond
> Graduate Research Assistant
> Florida State University
> Center for Ocean-Atmospheric Prediction Studies (COAPS)
> =======================================================
>