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20020219: Image query

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  • Subject: 20020219: Image query
  • Date: Tue, 19 Feb 2002 15:03:54 -0700
>From: Anthony James Wimmers <address@hidden>
>Organization: UVa
>Keywords: 200202192053.g1JKrYx27851 McIDAS-X AXFORM

Tony,

>Sorry to give you double duty, Tom, but I have a totally
>different kind of question for you too. I want to get the image
>data out of a piece of the image, with lat/lon coordinates
>(at like 1000 points at a time).

OK.

>Right now there's the IMGPROBE command, which gives
>brightness values for a given (line,element) or (lat,lon)
>domain, and there's the E command, which gives (lat,lon)
>for a (line,element) input.

Right, but IMGPROBE can be used to list out more than BRIT values.

>But I don't see any way to
>combine the two. Is there some way to get what I want
>besides by messing with the code?

You could use the AXFORM command, but that will create three different
files for output: data values in one, latitudes in another, and longitudes
in yet a third.

>The kind of output I'm looking for would look like this:
>
>lat    lon     brightness
>-------------------------
>44:30  105:21    201
>44:51  105:40    199 etc...
>
>or better yet,
>
>lat    lon     brightness temperature
>-------------------------------------
>44.50  105.35    190
>44.83  105.67    193 etc...

Since there is no routine that will do the exact listing you want, you
would be better off using AXFORM and then writing a little script to
read values from each of the three files I mention above to create the
listing you want.

A kind of more convoluted way to get what you want is to use IMGGRD
to turn the image portion you want into a grid in a GRID file, and
then use GRDINFO to list out the grid value(s).  I add this since
a GRDINFO listing can look like:

DATALOC ADD RTGRIDS WINDFALL.EVSC.VIRGINIA.EDU
 
GRDLIST RTGRIDS/AVN FORM=FILE ALL
DATASET NAME: RTGRIDS/AVN
 Dataset Position  Creation Date Max Grids         Directory Title
 ----------------  ------------- --------- -------------------------------
        9             2002049       5000   ALL  00Z AVN 0  HR<=VT<=24 HR
       10             2002050       5000   ALL  00Z AVN 0  HR<=VT<=24 HR
       39             2002049       5000   ALL  12Z AVN 0  HR<=VT<=24 HR
       40             2002050       5000   ALL  12Z AVN 0  HR<=VT<=24 HR
GRDLIST - done
 
GRDINFO RTGRIDS/AVN.40 LIST GRID=1 ROW=1 COL=1 5
Listing data from Z    Grid at 1000MB   from AVN  at 120000 UTC on 2002050
                          from dataset: RTGRIDS/AVN
    Row    Col    Latitude    Longitude    Value         Units  Level  Param
     1       1      35.494    -170.356   0.1020000E+03    GPM  1000 MB   Z
     1       2      36.949    -170.528   0.6740000E+02    GPM  1000 MB   Z
     1       3      38.421    -170.711   0.3490000E+02    GPM  1000 MB   Z
     1       4      39.912    -170.906   0.1040000E+02    GPM  1000 MB   Z
     1       5      41.420    -171.115   0.2900000E+01    GPM  1000 MB   Z
GRDINFO Done, Number of grids listed=1
GRDINFO - done

This is exactly the kind of listing you seem to be after, so the real
overhead is in running IMGGRD (a non-ADDE routine) to create the grid
that you can list the information from.

Tom

>From address@hidden Tue Feb 19 15:46:05 2002
>Subject: Re: 20020219: Image query 

re: You could use the AXFORM command, but that will create three different
files for output: data values in one, latitudes in another, and longitudes
in yet a third.

No problem. That's perfect. Thanks!

Tony