[ferret_users] dimension inconsistency?

[Ryo Furue <furue@xxxxxxxxxx>]

Ferret users,

I've noticed two (maybe related and probably minor) issues
about dimensionality of defined variables.

1) "show grid myvariable" shows dimensionanlity different
  from what's saved in a file

 yes? set data levitus_climatology
 yes? let tempmax = temp[x=@max,y=@max,z=@max]

tempmax is a scalar.

 yes? show grid tempmax
     GRID GMS1
  name       axis              # pts   start                end
  XAXLEVITR LONGITUDE          360mr   20.5E                19.5E(379.5)
  YAXLEVITR LATITUDE           180 r   89.5S                89.5N
  ZAXLEVITR DEPTH (m)           20 i-  0                    5000
  normal    T
 yes? save/file=tmp.nc tempmax

The "show grid" command still indicates that tempmax is a 3D variable
but when it's saved, it reduces to a scalar (zero-dimensional var.)
as it should.

2) In computation, the scalar causes a spurious dimension warning:

 yes? set data coads_climatology
 yes? fill/l=1 sst/tempmax[d=1]
  *** NOTE: Ambiguous coordinates on X axis: SST/TEMPMAX[D=1]
 yes? let a = 3
 yes? fill/l=1 sst/a
 !! no warming here.

Regards,
Ryo