[ferret_users] how to modify axis attributes

[Martin Schmidt <martin.schmidt@xxxxxxxxxxxxxxxxx>]

Hi ferreters,
I am trying to modify the attributes of axes and cannot get it working.

To demonstrate the problem consider the following short script:

____

use monthly_navy_winds.cdf

let t2 =2*UWND
SET ATT/OUTPUT  (`t2,return=xaxis`).point_spacing = "uneven"
save/clobber/file=dummy.nc/l=1 t2

____

The x-axis of uwnd has the attribute
                FNOCX:point_spacing = "even" ;

I would like to have it changed to uneven, whatever the reason is ...
                
After setting the attribute ferret answers 
!-> SET ATT/OUTPUT  (FNOCX).point_spacing = "uneven"

Fine. However, after saving and inspecting the outputfile with ncdump,
one finds
                FNOCX:point_spacing = "even" ;

What happens here?

Another question to the same problem:

How to define a new axis attribute?
DEFINE ATT/OUTPUT  (`t2,return=xaxis`).new_att = "somthing"

produces the answer
 !-> DEFINE ATT/OUTPUT  (FNOCX).new_att = "somthing"
but nothing is in the output?

Greetings,
Martin