20030617: Defining and accessing point data

>From: "Kwan-yin Kong" <address@hidden>
>Organization: CCNY
>Keywords: 200306171633.h5HGXmLd000512 McIDAS DSSERVE v2002

H Kwan-yin,

>      How are you?

Pretty well, thank you.  And you?

>Last time I contacted you about the 
>ADDE problem we had here at CCNY was on Mar 14, just 
>before the big snow storm that hit your area.  (I heard 
>the total snowfall total was 5 to 6 feet in the mountains. 
> Is that right?)

A small town just to the west of my house got 7 feet of snow.
I got 3.5 feet at my house, and it took me 2.5 days to dig
out from the storm.

>      In the past few days, I have been downloading McIDAS 
>images and MD files via the unidata2 neartime McIDAS 
>archives.  The files that I downloaded were *.goes12ir and 
>*.mdr.  I had no trouble defining, accessing, and 
>displaying the McIDAS images.

Good.

>But I am still having 
>trouble reading the *.mdr files, which I assume contains 
>the METAR, or point source data.

No, they contain Manually Digitized Radar (.mdr) imges.

>The way I define these *.mdr files was as follows.
>
>DSSERVE ADD SSEC/MD MD DIR='SSEC/*.mdr'
>
>The command executed without error messages, and when I 
>ran DSSERVE, it gave
>
>Group/Descriptor         Type  Format & Range     RT 
>Comment
>------------------------ ----- ------------------ -- 
>--------------------
>SSEC/MD                  POINT MD
>                                DIRFILE=SSEC/*.mdr
>
>But then when I ran the following command:
>
>PTLIST SSEC/MD.ALL
>
>The command was sent.  But it "hanged" (I waited a few 
>minutes and still saw nothing happened).  I am basically 
>stuck here, and have no other ideas what to do.

Two things:

1) the SSEC realtime archive no longer contains decoded POINT data

2) the unfortunate fact of life is that McIDAS v2002 and before do not
   support the access of MD file data in files named arbitrarily.  This
   means that you can could not define the dataset like you want:

DSSERVE ADD SSEC/MD MD DIR='SSEC/*.mdr'

Instead, you would need to either rename the files to conform to McIDAS
MD file naming conventions, or make links to the files to names that
follow those conventions.

The good news is that McIDAS v2003 (which should be released in mid-July)
does have the ability to define datasets in the way you like.

Tom