Re: Outlining grid boxes

[Ansley Manke <ansley.b.manke@xxxxxxxx>]

Hi Everyone,
I've fixed up the script mask_outline.jnl which I pointed to in my last 
message.
The new vewsion is linked it to the FAQ on outlining a region of grid 
boxes.
http://www.ferret.noaa.gov/Ferret/FAQ/custom_plots/outline_a_mask.html
Now it uses using the pseudo-variables XBOXLO, XBOXHI, etc. which did
not exist when the script was first written.  Mask_outline is now a bit 
more flexible,
working well whether we've defined a region or used an expression to set 
the variable.
It also works with irregular grids.

I also have the script show the alias for the command OVMO that it defines;
that way it's easier to see what the command does, and perhaps customize it.
I also added a second argument,  [color] to optionally set the color of 
the outline

yes? use etopo20
yes? let aust = rose[x=90:180,y=-45:0]
yes? shade/pal=greyscale aust
yes? let mask =  if aust gt 0 then 1 else 0
yes? go mask_outline mask  red
  Alias       Command
  -----       -------
  OVMO        cont/over/lev=(0.5,0.5,1,-3)/nolab/color=red rose_mo
*** Use the command alias "ovmo" to overlay the mask outline ***
yes? ovmo

Ansley Manke wrote:

> Hi John,
> Take a look at the FAQ,
> http://www.ferret.noaa.gov/Ferret/FAQ/custom_plots/outline_a_mask.html
>
> which shows a method of defining areas and outlining them using a script
> called mask_outline.jnl which is included in the Ferret distribution; I
> imagine you could modify this to outline individual grid boxes.
>
> I see that the script needs some updating; it creates variables for the
> upper and lower edges of grid boxes rather than using the 
> pseudo-variables
> XBOXLO, XBOXHI, etc.  I'll let you know when this is updated; right
> now it looks like it's only good for regularly-spaced grids.
>
> Ansley Manke
>
> John Krasting wrote:
>
> > I am using GFDL climate model output and I am trying to outline 
> > individual
> > grid boxes and areas of grid boxes.
> >
> > The GO BOX script uses latitude and longitude as its inputs.  Is 
> > there an
> > easier way to outline individual grid boxes without having to manually
> > compute the coordinates of the box corners?
> >
> >
> > ---------------------------------------------------------------
> > John Krasting
> >
> > Center for Environmental Prediction
> > Rutgers University
> > 14 College Farm Road
> > New Brunswick, NJ  USA 08901-8551
> > Phone:  +1-732-932-3890
> > Fax:  +1-732-932-8644
> > Email:  krasting@cep.rutgers.edu
> > ---------------------------------------------------------------
> >
> >
> >
> >
> >
> >