Re: [ferret_users] Overplot track data

["William S. Kessler" <William.S.Kessler@xxxxxxxx>]

Hi Charlotte -

You need to use PLOT/VS:

plot/VS/line/over/color=red lon,lat

Without VS, the command simply tries to plot the 2 variable  
separately (try a separate plot with your command omitting vs).

You also might want to make a dot for the individual stations:

plot/vs/sym=27/line=red/over lon,lat

Billy K

On Feb 6, 2007, at 8:59 AM, Charlotte Girard wrote:

> Hello,
> I would like to overplot a track on a current velocity field. I  
> managed to plot the current velocity field alone, and also the  
> track alone but I can't find a way to plot both of them!
>
> My track data (longitude, latitude) are stored in an ascii file  
> "track.res", with 2 columns. For instance:
>
> -83.0	25.0
> -84.0	28.0
> -85.0	26.0
>
> My programme looks like:
>
> ----beginning-------
>
> use "my_file.nc"	!file containing zonal (U) and meridional (V) speed
>
> set region/x=-90:-80/y=20:35/z=0/t=10-Aug-2006
> go mp_mercator
> set grid U
>
> !Plot the velocity field
> vector/lenght=1/XSKIP=3/YSKIP+3/overlay U,V
>
> !Plot the track
> file/format=delim/var="lon,lat" track.res
> list lon,lat
> plot/line/over/color=red lon,lat
>
> go fland 1
> frame/file=toto.gif
>
> -----end------------
>
> Ferret is not happy with the instruction "list lon,lat" and returns :
>
> **ERROR: illegal limits: "LON" is not in the range X=-90:-80
> 	Axis extremes are X=0.5:20480.5
> list lon,lat
> Command file, commande group, or REPEAT execution aborted
>
> Any suggestion?
> Thanks for you help !
>
> charlotte