Re: Symbols XAXIS_MIN, XAXIS_MAX

[Ansley Manke <Ansley.B.Manke@xxxxxxxx>]

Hi Patrick,
I'll have to look into what Ferret is doing when it defines the symbols
XAXIS_MIN, ($XAXIS_MIN) and so on, for time axes.  Here's
one way to do these overlays which I think is consistent.

yes? plot my_var
yes? let tt = t[gt=my_var]
yes? let t1 = tt[L=1]
yes? let t2 = tt[L=`var1, return=lend1`]
yes? plot/vs/over {`t1`, `t2`}, {($YAXIS_MIN),($YAXIS_MAX)}

Also see the related FAQ, "How can I overlay symbols on a plot
with a time axis? "
http://ferret.pmel.noaa.gov/Ferret/FAQ/custom_plots/time_series_symbol_overlay.html

And, this FAQ indicates that overlays on plots with time axes need to be
done with the overlay on a time axis whose units are hours: "How can I
overlay a time series on a SHADE or FILL plot? "
http://ferret.pmel.noaa.gov/Ferret/FAQ/custom_plots/time_series_overlay.html

Patrick Brockmann wrote:

> Hi all,
>
> Using last 5.51, I am trying to understand
> how to draw lines (dashed) over a plot on a time variable.
>
> A typical example would be:
> yes? plot my_var
> yes? plot/over/vs/line
> {`($XAXIS_MIN)`,`($XAXIS_MAX)`},{($YAXIS_MIN),($YAXIS_MAX)}
>
> I get what I want with
> yes? plot/over/vs/line
> {`(($XAXIS_MIN)+($XAXIS_MIN))`,`(($XAXIS_MAX)+($XAXIS_MIN))`},{($YAXIS_MIN),($YAXIS_MAX)}
>
> Unfortunatelly, this does not work everytime since in another plot,
> I have to use
> yes? plot/over/vs/line
> {`(($XAXIS_MIN)-($XAXIS_MIN))*60*60`,`(($XAXIS_MAX)-($XAXIS_MIN))*60*60`},{($YAXIS_MIN),($YAXIS_MAX)}
>
> Note the tranformations on values (XAXIS_MIN, XAXIS_MAX) from seconds to
> hours.
>
> So my question is: How to generalize this kind of overlay ?
>
> Any help on this point will be greatly appreciated.
> Attached a tar file with 2 examples.
>
> Patrick
>
> --
>
> mailto:Patrick.Brockmann@cea.fr
> 01.69.08.40.09 --> LSCE (Orme des merissiers 706, Bureau 3)
> 01.44.27.21.10 --> IPSL (Jussieu, Tour 26, 4eme)
> http://www.ipsl.jussieu.fr/~brocksce/
>
>   ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
>                        Name: err551_XAXIS.tar
>    err551_XAXIS.tar    Type: Unix Tape Archive (application/x-tar)
>                    Encoding: base64

--
Ansley Manke  Pacific Marine Environmental Laboratory  Seattle WA  (206)526-6246