Re: Negative longitudes

[Steve Hankin <hankin@xxxxxxxxxxxxx>]

Hi Mike,

The problem that you report is due to a bug in V5.22.  It has been fixed in
V5.3.

As a work-around for the problem in V5.22 try this:
   yes? def axis/x/units=deg/edges x1={-123,-122}

You can peek into the internals of the bug by noting the erroneous output of
SHOW AXIS/X (see the messed up "BOX_SIZE":

 yes? def axis/x/units=deg/modulo x1={-122.5}
 yes? show axis/x x1
  name       axis       # pts   start                end
  X1        LONGITUDE     1mr   122.5W(-122.5)    122.5W(-122.5)
           I     X                 BOX_SIZE
           1>  122.5W(-122.5)        -61.25

    - steve

-------

P.S. Do you really want "/modulo" for a single point axis? If so, then you
probably would want to make sure the axis span is 360 degrees as in
 yes? def axis/x/units=deg/edg/mod x1={`-122.5-180`,`-122.5+180`}
 yes? show axis/i=1:3 x1
  name       axis      # pts   start            end
  X1        LONGITUDE    1mi   122.5W(-122.5)   122.5W(-122.5)

           I     X                 BOX_SIZE
           1>  122.5W(-122.5)        360
           2>  122.5W                360
           3>  122.5W(597.5)         360

=======================================================

"McCann, Mike" wrote:

> Hi Ferreters,
>
> I'm trying to rename an axis and have encountered a strange thing
> that can be boiled down to this little example:
>
>   def axis/x/units=deg/modulo x1={-122.5}               ! Negative Long
>   let v1=x[gx=x1]
>   def axis/x/units=deg/modulo/name=x2 v1
>
> gives the error:
>
>   **ERROR: illegal limits: V1 is not in the range X=122.5W(-122.5)
>           Axis extremes are X=122.5W(-122.5)
>
> whereas
>
>   def axis/x/units=deg/modulo x1={122.5}                ! Positive Long
>   let v1=x[gx=x1]
>   def axis/x/units=deg/modulo/name=x2 v1
>
> gives no error.
>
> I've read
> http://ferret.wrc.noaa.gov/Ferret/Mail_Archives/fu_97/msg00031.html
> but would prefer not having to add 360 to my longitudes.
>
> Is the above example normal behavior?  Is there a simpler way to
> give an axis a new name?
>
> Thanks in advance,
> Mike
>
> --
> Mike McCann   (mccann@mbari.org)
> Monterey Bay Aquarium Research Institute
> 7700 Sandholdt Road
> Moss Landing, CA 95039-9644
> Voice: (831) 775-1769   Fax: (831) 775-1646 http://www.mbari.org/rd/iag.htm

--

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