Re: LAS/Ferret Image Display Issue

[Mark A Ohrenschall <Mark.A.Ohrenschall@xxxxxxxx>]

Hello,

We've found that this problem cropped up between versions 5.22 and 5.40 of Ferret. We've also found that the problem goes away in 5.40 if I make a certain change to the LAS configuration file, namely replacing month names in the time axis with something else, i.e., from

<lc_time type="t" units="months">
        <v>January</v>
        <v>February</v>
        <v>March</v>
        <v>April</v>
        <v>May</v>
        <v>June</v>
        <v>July</v>
        <v>August</v>
        <v>September</v>
        <v>October</v>
        <v>November</v>
        <v>December</v>
</lc_time>
to
<lc_time type="t" units="months">
        <v>Enero</v>
        <v>Febrero</v>
        <v>Marcha</v>
        <v>Abril</v>
        <v>Puede</v>
        <v>Junio</v>
        <v>Julio</v>
        <v>Agosto</v>
        <v>Septiembre</v>
        <v>Octubre</v>
        <v>Noviembre</v>
        <v>Diciembre</v>
</lc_time>
I've found that the three letter month abbreviations also seem to be "reserved"
and do not work.

Is this a bug, or is there a good reason why I'm not supposed to use month names?

There is a higher level issue here as well, but perhaps it is more of a netCDF issue. What is the proper way to describe monthly averages during the period from 1920 - 1980?

Related to this, I'm not sure how to properly describe the units of time. If I define a time dimension with units "hours" -- such as in the example given at http://www.unidata.ucar.edu/packages/netcdf-java/manual.htm#_Toc512937608 -- does this default to hours since some epoch? Or is it similar to my data above, except it's hourly averages, during some unknown period?

Thanks for all your help!

Mark

Jonathan Callahan wrote:

These lines are found in lasxml/server/jnls/draw_2d.tmpl.

        ppl %range 'PPL$ZMIN' 'PPL$ZMAX' 30
        ppl set PPL$RANGE_INC2 'PPL$RANGE_INC' * 2

Ferret uses the PlotPlus package to do graphics.  After a plot is
created in memory by PlotPlus (after a 'PLOT/.../set ...' command to
Ferret), certain parameters are available to the user as "plot plus
symbols".   These can be used to modify or further annotate and decorate
the plot before the graphic is actually generated.

The fact that LAS is complaining about these symbols not being found
means that PlotPlus didn't generate the plot.  There must be something
that happened further up in the output of GenericLAS_debug.txt that
identifies the problem.  The best way to debug is to extract all of the
lines of GenericLAS_debug.txt that begin with 'yes? ' and run Ferret
interactively.

I can't guess what happened to your plot from here.

Mark A Ohrenschall wrote:
>
>   Symbol not found
>   %range 'PPL$ZMIN' 'PPL$ZMAX' 30
>           ^
>   Symbol not found
>   set PPL$RANGE_INC2 'PPL$RANGE_INC' * 2
>
> What do the above messages mean (gotten from
> log/GenericLAS_debug.txt)? This message corresponds to requesting a
> GIF from LAS and seeing only the NOAA/PMEL TMAP Ferret Ver 5.40 logo
> at the top and nothing else (not even a data set or variable title).