Re: [ferret_users] shade + plot/vs and curvilinear grid

[Luiz Alexandre de Araujo Guerra <guerra@xxxxxxxxxxxxxxxxxx>]

Hi Ansley,

Thank you very much! It worked fine.

Best regards,

Alex
--
Luiz Alexandre Guerra
Aluno de Doutorado / Graduate Student

Universidade Federal do Rio de Janeiro / Rio de Janeiro Federal University
COPPE/PEnO / Ocean Engineering Program

---------- Original Message -----------
From: Ansley Manke <ansley.b.manke@xxxxxxxx>
To: Luiz Alexandre de Araujo Guerra <guerra@xxxxxxxxxxxxxxxxxx>
Cc: oar.pmel.ferret_users@xxxxxxxx
Sent: Thu, 17 Jan 2008 10:28:44 -0800
Subject: Re: [ferret_users] shade + plot/vs and curvilinear grid

> Hi Luiz,
> The values need to be numbers, without any W or S designation. I'm 
> guessing that this will work:
> 
>   shade var,lon,lat
>   plot/vs/ov {350,350},{-35,-25}
> 
> After you draw the plot with the curvilinear SHADE or FILL command,
>  look at the symbols that describe the longitude and latitude range 
> of the plot axes.
> 
> SHOW SYMBOL PPL$XMIN, PPL$XMAX
> SHOW SYMBOL PPL$YMIN, PPL$YMAX
> 
> Your list of points need to lie within these ranges for them to show 
> up on the plot. That is, PLOT/VS does not automatically add or 
> subtract 360 from the longitudes to match the modulo X axis of the 
> plot (this is true even if we're not in curvilinear coordinates).
> 
> If the points are in variables, say xpts and ypts, there's no reason 
> to check them by hand; you could do something like this:
> 
>   shade var,lon,lat
>   plot/vs/over xpts,ypts
>   let xmin = xpts[x=@min]
>   let xmax = xpts[x=@max]
>   IF `xmin lt ($ppl$xmin)` THEN plot/vs/over/nolab xpts+360,ypts
>   IF `xmax gt ($ppl$xmin)` THEN plot/vs/over/nolab xpts-360,ypts
> 
> Luiz Alexandre de Araujo Guerra wrote:
> > Dear coleagues,
> >
> > I am trying to make a figure using shade and plot/vs to draw a line but I have
> > a problem. My data file is a model output with curvilinear grid. So, I use
> > shade with three parameters: "shade var,lon,lat". I want to draw a meridional
> > line. I have been tried: "plot/vs/ov {10W,10W},{35S,25S}" or "plot/vs/ov
> > {-10,-10},{-35,-25}" and both result an error message. I have already tried:
> > "plot/vs/ov {3574,3574},{1037,1182}" (grid model indexes) and nothing
happened.
> >
> > I have read some group messages about the use of @itp transform to draw lines
> > in time series figures. I had success with that method and I expected to adapt
> > it to my problem... but it didn´t work too.
> >
> > I was wondering if the Ferret group could help.
> >
> > Thanks for your attention.
> >
> > Best regards,
> >
> > --
> > Luiz Alexandre Guerra
> > Aluno de Doutorado / Graduate Student
> >
> > Universidade Federal do Rio de Janeiro / Rio de Janeiro Federal University
> > COPPE/PEnO / Ocean Engineering Program
> >
> >
------- End of Original Message -------