[ferret_users] Re: Vertical Axis Truncated during REPEAT: GO MYSCRIPT

[Alexander Audet <alexander.c.audet@xxxxxxxxx>]

Hello Ferret Users,

                                 I have figured out a solution to my problem was to replace my REPEAT/K=1:8:1  with REPEAT/Range=1:8:1/Name=kk. 

USE ERA5_UV8PLbottom_DJF.nc

let zval = z[gz='U']

REPEAT/Range=1:8:1/Name=kk \

(let NamePL = zval[k=`kk`]; \

Go RawERA5WindSpeed `kk`, `NamePL`, DJF)

I still don't understand the behavior though. I noticed that when I used REPEAT/K=8:1:-1, some of my Go script intermediate files which only had 1 pressure level failed because they did not have 8 z-levels, and REPEAT somehow seemed to impose the rule inside the script that all datasets needed to give data on the current K-iteration z-level (a.k.a. their 8th z-level). 

It also appears that REPEAT/K=1:8:1, created a pseudo variable on an abstract axis with unlimited points, but that after my go-script, the abstract grid of the pseudo variable has been replaced by a non-abstract grid with a set pressure level. 

REPEAT/Range also creates a grid with a single fixed pressure level, but don't seem to have a problem moving to a new grid on the next count. 

I would like to better understand what is going on here. Any ideas? Perhaps I need to refresh my understanding of abstract axes? 

Regards,

Alexander

On Thu, Sep 3, 2020 at 6:15 PM Alexander Audet <alexander.c.audet@xxxxxxxxx> wrote:

Hello All,

               When I perform my REPEAT over a GO MYSCRIPT, it seems to truncate my vertical axis, and I get the following error:

!-> REPEAT: K=2

 **ERROR: illegal limits: "K" does not exist at K=2

          Axis extremes are K=1

USE ERA5_UV8PLbottom_DJF.nc

let zval = z[gz='U']

REPEAT/K=1:8:1 \

(let NamePL = zval; \

Go RawERA5WindSpeed `k`, `NamePL`, DJF; \

USE ERA5_UV8PLbottom_DJF.nc)

Within the Go script, (quite lengthy so I won't include it here just yet), I create new axis, grids, datasets, open them, cancel them multiple times. To try to preserve the state, I put the following sandwiching the beginning and end of my script. 

SET GRID/SAVE

SET DATA/SAVE

DEFINE REGION/DEFAULT save

CANCEL DATA/ALL

CANCEL GRID

CANCEL AXIS/ALL

CANCEL VAR/ALL

SET DATA/RESTORE

SET GRID/RESTORE

DEFINE REGION/DEFAULT save

Simpler REPEAT over the same dataset work just fine:

REPEAT/K=1:8:1 list/I=1:1/J=1:1/L=1:1 'U'

So what am I missing? As a last attempt, I tried to add the last part above USE ERA5_UV8PLbottom_DJF.nc, to the end of my repeat, to no effect.

Many Thanks and Regards, 

Alexander