Re: regridding problem (sub-global to global lat-long grid)

[Ansley Manke <ansley@xxxxxxxxxxxxx>]

Hi Lev,
You should be able to do this kind of thing. I wonder if the trouble
has something to do with the regions you use for the data or some
such thing.  I was able to do this:

1) Create a dataset on part of the globe, like your first set:

> yes? def axis/x=163w:8w:1/units=degrees xlonb
> yes? def axis/y=36.75n:84.75n:0.25/units=degrees ylatb
> yes? def grid/x=xlonb/y=ylatb gdk1
> yes? let hd3a = x[g=gdk1]/10. + y[g=gdk1]/10.
> yes? save/file=nonmod.nc hd3a
2) New Ferret session, use this data along with some gridded modulo data
> use nonmod.nc
> use levitus_climatology
> show data
> shade  hd3a[d=1,g=glevitr]
> shade temp[d=2,k=1] - hd3a[d=1,g=glevitr]
Are you setting any regions?  What kind of things are you doing
when you go to use the data?

Ansley Manke

Lev Tarasoff wrote:

I'm trying to blend two data sets. One (variable hd3a) defined on
    GRID GDK1
 name       axis              # pts   start                end
 XLONB     LONGITUDE          156 r   163.5W               8.5W
 YLATB     LATITUDE            97 r   36.75N               84.75N
The netcdf file was created in ferret.
I want to blend this data into data from another netcdf file (not
created in ferret) which has the global grid:
    GRID GBA1
 name       axis              # pts   start                end
 LON       LONGITUDE          360mr   179.5W(-179.5)       179.5E
 LAT       LATITUDE           180 r   89.5S                89.5N

however, when I try to regrid from GDK1 to GBA1, I get all data flagged
as bad data when using
hd3b=hd3a[g=GBA1]

If I try
hd3b=hd3a[g=GBA1@mod]
I get the following error:
 **ERROR: regridding: @MOD regridding to a non-modulo axis: HD3A

Regridding variables from the 2nd data set to GRID GDK1 does work
however (non-modulo regridding).

help

thanks

Lev

Lev Tarasoff -  Dept of Physics, University of Toronto,
                60 St. George St., Toronto, Ontario, CANADA, M5S 1A7
                Tel (519)-821-3555  Fax (416)-978-8905
                email: lev@atmosp.physics.utoronto.ca

--
Ansley Manke  Pacific Marine Environmental Laboratory  Seattle
WA  (206)526-6246