[ferret_users] How to grab z axis info?

[Szymon Roziewski <szymon.roziewski@xxxxxxxxx>]

Hello Ferreters,
I do an interpolation and as a result I get a variable without time axis and z axis information. 
So I need to fill these gaps. With time axis I have no problem.

let tmp_t = temperature[k=10, l=1]
define axis/t="`t[g=tmp_t,l=1],return=tend`":"`t[g=tmp_t,l=1],return=tend`":1 time
let timestamp = 0* t[gt=time]

This above works.

The problem starts when I proceed to z axis info.
I have a problem with getting this info from origin variable.

I've been trying to get there by that

list "`Z[g=tmp_t,k=10],return=tend`"

but with failure.
 **ERROR: command syntax: *
          * may not start an _expression_
list "*"

When I renamed z variable into e.g. zs using ncrename I didn't help me.

Could you give me please any suggestions?
I also attach the picture in order to see what I want to get (red line).

I need to add that my netCDF has a following structure (ncdump):

dimensions:
        time = UNLIMITED ; // (86 currently)
        z = 10 ;
        y = 145 ;
        x = 132 ;
variables:
        float temperature(time, z, y, x) ;
                temperature:long_name = "potential temperature" ;
                temperature:units = "C" ;
                temperature:coordinates = "east_e north_e zz" ;
        float east_e(y, x) ;
                east_e:long_name = "easting of elevation points" ;
                east_e:units = "metre" ;
        float north_e(y, x) ;
                north_e:long_name = "northing of elevation points" ;
                north_e:units = "metre" ;
        float zz(z) ;
                zz:long_name = "sigma of cell centre" ;
                zz:units = "sigma_level" ;
                zz:standard_name = "ocean_sigma_coordinate" ;
                zz:formula_terms = "sigma: zz eta: elb depth: h" ;
        float z(z) ;
                z:long_name = "sigma of cell face" ;
                z:units = "sigma_level" ;
                z:standard_name = "ocean_sigma_coordinate" ;
                z:formula_terms = "sigma: z eta: elb depth: h" ;

and in ferret (show data/att)

(time)                 FLOAT     long_name       CHAR        4    T       time
                                 orig_file_axnameCHAR        4    F       time
  
(z)                    FLOAT     long_name       CHAR        18   T       sigma of cell face
                                 units           CHAR        11   T       sigma_level
                                 standard_name   CHAR        22   F       ocean_sigma_coordinate
                                 formula_terms   CHAR        26   F       sigma: z eta: elb depth: h
                                 orig_file_axnameCHAR        1    F       z
 temperature           FLOAT     long_name       CHAR        21   T       potential temperature
                                 units           CHAR        1    T       C
                                 coordinates     CHAR        17   F       east_e north_e zz



-- 
Z wyrazami szacunku,
Szymon Roziewski

Attachment: temp.gif
Description: GIF image