Creating 3D grid from scattered data

["McCann, Mike" <mccann@xxxxxxxxx>]

Hi,

I have a set of scattered ocean observations that I'd like
to grid into a 3D volume.  The strategy I'm considering is

1. Create horizontal sections and grid to a level with
   scatter2gridlaplace_xy()

2. Assemble these sections into a 3D volume following the
   multiple-slab example:

yes? DEF AXIS/x=1:360:1  xaxis
yes? DEF AXIS/y=1:180:1  yaxis
yes? DEF AXIS/Z=0:100:25/DEPTH  zaxis
yes? DEF GRID/X=xaxis/Y=yaxis/Z=zaxis uv_grid
yes? DEF AXIS/Z=0:0:1  zaxis1
yes? DEF GRID/LIKE=uv_grid/Z=zaxis1  uv_grid1
yes? FILE/GRID=uv_grid1/BAD=-999/VAR="u,v"  uv.data1
yes? LET/TITLE="My U data"  u1 = u[G=uv_grid]
yes? LET/TITLE="My V data"  v1 = v[G=uv_grid]
yes? SAVE/FILE=uv1_5z.cdf/KLIMITS=1:5  u1, v1
yes? CANCEL DATA uv.data1
yes? DEF AXIS/Z=25:25:1  zaxis1
yes? FILE/GRID=uv_grid1/BAD=-999/VAR="u,v"  uv.data2
yes? SAVE/FILE=uv1_5z.cdf/APPEND  u1,v1
. . . 

My problem is that I need to get the output of scatter2gridlaplace_xy()
onto a 3D grid where the Z axis is a single value.  How can I do this?

I tried 
SET VAR/GRID=newgrid <variable_from scatter2gridlaplace_xy()>
but I get an error.

I think I can list the level out to an ascii file, then read it back
in onto the 3D grid, but I'd rather not have to do this.  Is there
a more efficient way?

Thanks in advance,
Mike

--
Mike McCann   (mccann@mbari.org)
Group Leader, Information Applications Group
Monterey Bay Aquarium Research Institute
7700 Sandholdt Road
Moss Landing, CA 95039-9644
Voice: (831) 775-1769   Fax: (831) 775-1646 http://www.mbari.org/rd/iag.htm