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20050705: output of TEMP values in AXFORM (cont.)

>From: "Mekonnen Gebremichael" <address@hidden>
>Organization: Pratt School of Engineering, Duke University
>Keywords: 200504201601.j3KG1gv2005753 McIDAS probing image values

Hi Mekonnen,

>I extracted the data in ascii format for one of the GOES-8 files. I did this
>'imgcopy.k IR/AREA MYDATA/IMAGES.300 LATLON=37 94 SIZE=419 1832'. In this
>command, I used the information that I retrieved from 'imglist.k IR/AREA
>FORM=ALL'; that is, I copied the entire data. I plotted it using matlab, and
>I have attached the result (large.jpeg).

The images you sent me look strange to me.  Can you confirm that 
the following images look the same as the ones you have locally:

http://www.unidata.ucar.edu/content/staff/tom/gifs/large.jpg
http://www.unidata.ucar.edu/content/staff/tom/gifs/subset.jpg

The thing that looks most odd to me is the ring-like pattern throughout
the images.

>Using my programs in IDL, I cutout a window bounded by (25 N - 43 N ; 105 W
>- 90 W), and re-gridded it at 0.1degree resolution. I plotted the result
>using matlab (see subset.jpeg). 

subset.jpg looks odd to me in the same way that large.jpg looks odd.

>I am not happy with the image subset.jpeg; it looks something is wrong. Is
>there a way to cut out the image in mcidas that corresponds to my window (25
>N - 43 N ; 105 W - 90 W)?

Yes, when you do the IMGCOPY (imgcopy.k), only copy the sector that you
are interested in.  The location keywords in McIDAS support selecting
by position (Lat,Lon and Station ID) and by image raster location
(Line,Element).  My advice is to create the sector desired from the original
and then use AXFORM (axform.k) to list out the values in the units you
want.

>Or better, is there a way to cut out the image in
>mcidas that corresponds to my window at 0.1degree resolution?

Another thing that might be causing your images to look different from
what you expect is the projection.  You are taking an image in GOES
projection (at least I think that this is the case; aren't you now
using unremapped GOES images instead of the rectilinear composites
you originally were interested in?) and then treating the values
like they were in regularly spaced Lat,Lon coordinates (i.e., rectilinear).

>Thanks a lot,

No worries.

>FYI, the data is
>'/disk/space/mek11/USdata/GOESssec/184/goes8_4_2002_184_1015.area'

I might not get the opportunity to check your results by logging in.
I am working on the next McIDAS release at the moment and then will
be diving into creating a new set of documentation and workshop
materials based on the new release.

Cheers,

Tom
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