regridding

[Carol Ladd <cladd@xxxxxxxxxxxxxxxxxxxx>]

Hi. 

I am trying to get a dataset of depth of specified isopycnals from the
levitus monthly climatology.  The depth of the isopycnals is easy to
calculate:

THETA = THETA_FO(SALT,TEMP,Z,0)
SIGMA_TH = RHO_UN(SALT,THETA,0)-1000
DEPTH1 = SIGMA_TH[Z=@LOC:22.5]

Now DEPTH1 is still on the same grid as the levitus data which includes 19
depth levels.  However, DEPTH1 only has one value along the depth axis.
So how do I regrid to a z axis with only one value?

I have tried 

define axis/z=1:1:1 zax   
let d2=depth1[gz=zax] 
contour d2
 **ERROR: invalid command: attempt to regrid on a compressed axis

and numerous variations on this.

I have also tried the new RESHAPE function:

DEPTH1 = SIGMA_TH[Z=@LOC:22.5,l=9]
define axis/z=1:1:1 zax1
define axis/t=1:1:1 tax1
let outgrid=x[g=temp,i=1]+y[g=temp,j=1]+z[gz=zax1,k=1]+t[gt=tax1,l=1]
show grid outgrid
let d1=RESHAPE(depth1,outgrid)
show grid d1
    GRID (G002)
 name       axis              # pts   start                end
 XAX_LEV9421_380 LONGITUDE    360mr   20.5E                19.5E(379.5)
 YAX_LEV94 LATITUDE           180 r   89.5S                89.5N
 ZAX1      Z                    1 r   1                    1
 TAX1      T                    1 r   1                    1

 
However, when I try to contour d1, it tells me it is not a 2D field.
When I ask for a list of a 2D region, it only gives me one value along the
y axis:

 list/x=130e:135e/y=20n:25n d1
             RESHAPE(DEPTH1,OUTGRID)
             Z: 1
             T: 1
             DATA SET: /loon/data/ocean_atlas_monthly.cdf
                 20.5N 
                111
 130.5E / 111:  56.86
 131.5E / 112:  56.84
 132.5E / 113:  57.13
 133.5E / 114:  57.45
 134.5E / 115:  57.60

I can get a list of the 2D field but only if I specify each place along
the y axis separately:

list/i=111:130 d1[j=106],d1[j=107],d1[j=108]

             DATA SET: /loon/data/ocean_atlas_monthly.cdf
             World Ocean Atlas 1994 * 1x1 Degree Monthly Means
             LONGITUDE: 130E to 150E
             Z: 1
             T: 1
 Column  1: D1[Y=15.5N] is RESHAPE(DEPTH1,OUTGRID)
 Column  2: D1[Y=16.5N] is RESHAPE(DEPTH1,OUTGRID)
 Column  3: D1[Y=17.5N] is RESHAPE(DEPTH1,OUTGRID)
                 D1     D1     D1 
130.5E / 111:  89.43  82.21  74.37
131.5E / 112:  89.51  82.32  74.50
132.5E / 113:  89.01  81.98  74.42
133.5E / 114:  88.24  81.39  74.14
134.5E / 115:  87.58  80.78  73.74
135.5E / 116:  87.18  80.29  73.30

Am I missing something?  Is there any other way to do this?

Thanks for any help anyone can give me on this.

************************************************************
Carol Ladd
University of Washington
School of Oceanography
Box 357940                      (206) 543-5214
Seattle, WA  98195-7940         cladd@ocean.washington.edu
************************************************************