LAS 6.4.1 : trouble adding/displaying DODS/OPeNDAP dataset (fwd)

[Rob Cermak <cermak@xxxxxxxxxxxx>]

Having a spot of trouble... LAS 6.4.1

Currently, I've found a great source for archived and near real time model 
output.   http://nomads.ncdc.noaa.gov/data-access.html

The specific data item (description) I would like to add is:
  
http://nomads.ncdc.noaa.gov:9090/dods/NCDC_NOAAPort_GFS/200501/20050114/gfs-mrf_203_20050114_0000_fff.das

The structure indicates COARDS, although it is not from a pure
OPeNDAP/DODS source, but a hybrid GrADS-DODS server.

Adding the included XML file did not seem to produce any problems.   

addXml.pl --out_inc template.xml NCDC_AVN.xml 
http://nomads.ncdc.noaa.gov:9090/dods/NCDC_NOAAPort_GFS/200501/20050114/gfs-mrf_203_20050114_0000_fff

Produced XML file is here:
  http://penguin.sfos.uaf.edu/NCDC_AVN.xml

The dataset shows up for selection with the variables.   The multilayer 
variables allow for level selection in the contraints area.   After 
defining an area to plot, this output is found:

LAS Error
The following error message was received from LAS:

Adding an acceptable error string: "*** NOTE: ".
 	NOAA/PMEL TMAP
 	FERRET v5.70  
 	Linux(g77) 2.4.20 - 06/28/04
 	18-Jan-05 10:34     

yes? cancel mode verify
yes? cancel mode interp
yes? canc data/all
yes? go std_initialize 
"http://nomads.ncdc.noaa.gov:9090/dods/NCDC_NOAAPort_GFS/200501/20050114/gfs-mrf_203_20050114_0000_fff"; 
"1" "1" "rh"
Program quit unexpectedly.21191:21191 at ../xml/perl/CLC.pm line 359.

Looks like a Ferret crash.  I've not found a way to do further debugging.   
I can start ferret manually and perform the above steps, no problem.  What 
is the next piece of code?   

Ferret seems to open the dataset.  

yes? use 
"http://nomads.ncdc.noaa.gov:9090/dods/NCDC_NOAAPort_GFS/200501/20050114/gfs-mrf_203_20050114_0000_fff";
yes? show data
     currently SET data sets:
    1> 
http://nomads.ncdc.noaa.gov:9090/dods/NCDC_NOAAPort_GFS/200501/20050114/gfs-mrf_203_20050114_0000_fff  
(default)
 name     title                             I         J         K         
L
 RH       relative humidity [%]            1:103     1:33      1:7       
1:21
 NO5WAVE  5-wave geopotential height [gpm  1:103     1:33      ...       
1:21
 P        total precipitation              1:103     1:33      ...       
1:21
 PC       convective precipitation         1:103     1:33      ...       
1:21
 RHB      bottom 30mb relative humidity [  1:103     1:33      ...       
1:21
 RHL2     relative humidity, sigma 0.44 t  1:103     1:33      ...       
1:21
 SLP      sea level pressure [pa]          1:103     1:33      ...       
1:21
 T        temperature [k]                  1:103     1:33      1:7       
1:21
 TB       bottom 30mb temperature [k]      1:103     1:33      ...       
1:21
 U        u winds [m/s]                    1:103     1:33      1:7       
1:21
 UB       bottom 30mb u winds [m/s]        1:103     1:33      ...       
1:21
 V        v winds [m/s]                    1:103     1:33      1:7       
1:21
 VB       bottom 30mb v winds [m/s]        1:103     1:33      ...       
1:21
 VORT     absolute vorticity [/s]          1:103     1:33      1:7       
1:21
 Z        geopotential height [gpm]        1:103     1:33      1:7       
1:21

yes? contour RH[K=7,L=1]

produces:
  http://daved.ims.uaf.edu/~cermak/las/ferret.png

Is there a way to dynamically represet datasets from LAS (able to add 
datasets in real time?)

Handling the time is fairly straightforward, but the DODS filename
changes.   At this point, the XML input into LAS is fairly static.  If we 
have to tweak the filenames, then we have to run genLas.pl again.

If we can get this one item operational, it would complete a demonstration
project showing how a single data source could be accessible by:

LAS and other client programs that talk to LAS and DODS/OPeNDAP.

Client programs viewing the same dataset:

ODC (OpenDAP client) : http://www.opendap.org/ODC/
   http://daved.ims.uaf.edu/~cermak/las/odc.png

IDV (Unidata's OpenDAP client) : 
   http://my.unidata.ucar.edu/content/software/idv/index.html
   http://daved.ims.uaf.edu/~cermak/las/idv.png

ncBrowse (now talks to LAS servers)
   http://www.epic.noaa.gov/java/ncBrowse/
   http://daved.ims.uaf.edu/~cermak/las/ncbrowse.png

Any future heavy duty LAS workshops?  Focused on those entering the
development/deployment aspects of a LAS server for handling near-real time
data?

We are also watching deployment of OGC type servers (MapServers, etc),
examples:  http://www.openioos.org/

LAS has the leg up on these type servers as they mainly provide end user
graphics -- there are also companion WMS map servers.  No real ability yet
to download data they display and lack of a client base.  My hope is that
OGC and OPeNDAP standards kinda work towards interoperability. It looks
like all the parts are out there... just a matter of getting it all to
work.

Looking forward to the future release(s) of LAS this year.

Rob
-- 
Rob Cermak : 907-474-7948/7092 : FAX 907-474-7204 : PGP = 0x75869A6E
Software and Systems Engineer : Information Systems and Data Management
School of Fisheries and Ocean Sciences : University of Alaska Fairbanks
cermak@sfos.uaf.edu : fnjrc1@uaf.edu : ED9U1M7P01@alaska.edu