Re: SCAT2GRIDGAUSS_YZ

[Sophie Cravatte <Sophie.Cravatte@xxxxxxxxxxxxxxxxx>]

Hi Ansley,

The documentation on the web needs indeed to be changed, because it is
written that F may be a function of time (and not of X). It is also
written that the result axes are: X: normal (no axis); Y: inherited from
XAXPTS, Z also and T inherited from F.

Thanks for your help!

SOphie





On Wed, 2005-06-01 at 23:54, Ansley Manke wrote:
> Hi Sophie,
> Billy gives good arguments for why you might not want to use one of
> the scat2grid_yz functions at all.  I just want to add that the way
> you're reading your data is the reason for the result being in i, y,
> and z (and it shows where we need to clarify the documentation.) Your
> data are lists of values on an I axis.  If you look at the function
> details
> 
> yes? show function SCAT2GRIDLAPLACE_YZ
> SCAT2GRIDLAPLACE_YZ(YPTS,ZPTS,F,YAXPTS,ZAXPTS,CAY,NRNG)
>     Use Laplace interpolation to grid scattered data to a YZ grid.
>     YPTS: y-coordinates of scattered input triples
>     ZPTS: z-coordinates of scattered input triples
>     F: F(Y,Z) 3rd component of scattered input triples. May be fcn of
> X and/or T  
>     YAXPTS: Y axis coordinates of a regular output grid
>     ZAXPTS: Z axis coordinates of a regular output grid
>     CAY: Interpolation parameter: CAY
>     NRNG: Interpolation parameter: NRNG
> 
> 
> You will see that the third argument "F(Y,Z) may be fcn of X and/or
> T".  This means that one could use the function to grid a whole set of
> Y-Z slices, at different values of X.  (or, think of a whole set of
> x-y planes at different Z levels with one of the scat2grid*xy
> functions).
> 
> If you do this problem with scat2gridgauss_yz, make the lat, depth,
> temp values be on a Y or Z axis.
> 
> let ylat = YSEQUENCE(lat)
> let ydepth = YSEQUENCE(depth)
> let ysalt = YSEQUENCE(salt)
> let salinite
> =SCAT2GRIDGAUSS_YZ(ylat,ydepth,ysalt,y[gy=yaxs],z[gz=zaxs],2,2,2,2)
> Ansley
> 
> Sophie Cravatte wrote:
> > Dear Ferret users,
> > 
> > I can't figure out how to use the function SCAT2GRIDGAUSS_YZ to grid
> > scattered data to a YZ grid.
> > Here is my script:
> > 
> > define axis/y=20S:5S:1/units=degrees yaxs
> > define axis/z=0:500:1/units=meters/depth zaxs
> > SET DATA/EZ/var="lat,depth,temp,salt,o1,o2,dens" r165e.dat
> > 
> > let salinite
> > =SCAT2GRIDGAUSS_YZ(lat,depth,salt,y[gy=yaxs],z[gz=zaxs],2,2,2,2)
> > 
> > And instead of having a 2-D YZ field for salinite, I got a 3-D i,Y,Z
> > field, and of course with stupid values.
> > What's wrong in my script? What didn't I understand?
> > 
> > Thanks a lot for your help,
> > 
> > Sophie
> > 
> > 
> >   
-- 
Sophie Cravatte
LEGOS--14 av. Ed. Belin--31400 TOULOUSE
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