Re: [ferret_users] vertical cross section along a ship track

[Jaison Kurian <jaison@xxxxxxxxxxxxxxxxxx>]

Hi Aleksi,
             Still some basic details are missing and hence it is 
difficult to give a neat answer to your question. If you have 
provided the results of "show data" and "show grid V" commands, it
must have been much more easier to suggest a solution. Here are some
points (based on your first mail), which will help you :

1. What is the data format ? If it is ASCII, how did you load/read
       the data in Ferret? Have you used any GRID (like FILE/GRID=)?

2. What are the dimensions/grid of the variable "V"? (output of 
       "show data" and "show grid V" commands; output of "ncdump -c"
        is also usefull, if the data is in NetCDF format). 

3. The result of slantV=SAMPLEXY(V,xtrack,ytrack), will have a 
        X-axis and T/Z depending on its initial/original grid.
        Assume that it does have only Z-axis. Now the X-axis of
        "slantV" will not have a proper definition as it is abstract,
        resulting from the SAMPLEXY function. So define a new X-axis
        and assign it using "@ASN" regridding. Here the number of 
        points should be equal to number of "xtrack" (="ytrack");
        let it be 50 :

           define axis/x=1:50:1 xpoints

           let V_track = slantV[gx=xpoints@ASN]

           FILL/levels=...../vlim=.... V_track

       You can also use the RESHAPE command to this effect.

If you have any questions on above explanation, please mail back to
the list with answers to points 1 and 2 above.

Regards,

Jaison



On Mon, 28 May 2007 aleksi.nummelin@xxxxxxxxxxxxxxx wrote:

> HI
> 
> Here is some more info about my problem (see my previous 
> message on the bottom):
> 
> whole error message:
> 
> **ERROR: dimensions improperly specified: 9999999 words 
> were requested.
>   *** NOTE: Check for unspecified limits on an ABSTRACT 
> axis
>   *** NOTE: Use the SHOW GRID command to see the axes
> 
> I tried to specify abstract axis but obviously it didn't 
> work .  I can also plot the ship track,
> so I guess the problem is not  track itself.
> 
> One of the tracks I tried to use:
> 
> yes? LET/QUIET xlon1 = 22
> yes? LET/QUIET xlon2 = 24
> yes? LET/QUIET xlon3 = 28
> yes? LET/QUIET ylat1 = 59.5
> yes? LET/QUIET ylat2 = 59.7
> yes? LET/QUIET ylat3 = 60.2
> yes? LET/QUIET XLEG1 = xlon1 + (L-1)*(xlon2-xlon1)
> yes? LET/QUIET XLEG2 = xlon2 + (L-1)*(xlon3-xlon2)/3
> yes? LET/QUIET YLEG1 = ylat1 + (L-1)*(xlon2-xlon1)
> yes? LET/QUIET YLEG1 = ylat1 + (L-1)*(ylat2-ylat1)
> yes? LET/QUIET YLEG2 = ylat2 + (L-1)*(ylat3-ylat2)/3
> yes? LET/QUIET XTRACK = IF L LE 2 THEN XLEG1 ELSE XLEG2
> yes? LET/QUIET YTRACK = IF L LE 2 THEN YLEG1 ELSE YLEG2
> 
> I thought the problem might be the variable L so I tried I 
> and J and even A (wich was my own variable),
> but none of them worked.
> 
> My PREVIOUS MESSAGE:
> 
> Hi!
> 
> I have tried to make a vertical profile along a ship 
> track, but I get just this:
> 
> ERROR: dimensions improperly specified: 9999999 words were 
> requested.
> 
> I have used script
> 
> LET slantV = samplexy(V,xtrack,ytrack)
> FILL/LEVELS=(-1,1,0.1)/VLIMITS=0:100 slantV
> 
> V is variable (meridional velocity). According to users 
> guide this should work,
> and it does when I make a profile along a simple line,
> so do you have any ideas what I'm doing wrong when trying 
> to plot along a ship track?
> 
> Thanks (for previous answers too)!
> 
>   - ALEKSI NUMMELIN -
> 
>