Re: [ferret_users] scat2gridgauss not functioning properly

[Stephen Guimond <sguimond@xxxxxxx>]

Hi Jaison,

Thank you for your response, using a 1-D axis for x and y input values worked.  I suppose the "objective_analysis_demo" script should be fixed because it shows 2-D axes for x and y input.

Another thing I found was that using "scat2gridlaplace" causes a crash of FERRET.  I used similar input as I did with "scat2gridgauss", but with cay and nrng both equal to 5.  I am using FERRET v6.1  for 32-bit Linux.  Have you found anything similar?

Thanks,
Steve


----- Original Message -----
From: jaison@xxxxxxxxxxxxxx
Date: Wednesday, August 20, 2008 9:51 pm
Subject: Re: [ferret_users] scat2gridgauss not functioning properly
To: guimond@xxxxxxxxxxxxx
Cc: ferret_users@xxxxxxxx

> 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 
> followinglines
> 
>   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)
> > =======================================================
> >
> 
> 
> 
> 

=======================================================
Stephen R. Guimond
Graduate Research Assistant
Florida State University
Center for Ocean-Atmospheric Prediction Studies (COAPS)
=======================================================