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[McIDAS #SXY-331778]: Unable to add historical wind profiler case study to ADDE server.



Hi Samuel,

re:
> I must apologize, but I'm not certain that the philosophy of posting support 
> e-mails on the web
> is of much benefit.

The webified versions of past end-user and Unidata Support interactions is the 
typical way
that netCDF software users support themselves.  We have had very good feedback 
over the
years from users who have said that they have found the answers to their 
questions using
simple web searches.

> If the command syntax/keywords of a particular operation change, and someone
> is trying to do the same operation X years later, they will try the wrong 
> command/syntax.

You are correct in the case where command syntax changes.  In the case of 
defining ADDE datasets, 
this is not the case, however.  The McIDAS command syntax has been almost 100% 
fixed for the
past decade or more.

> I've spend the past 4 hours looking thru Unidata's e-mail archive, and have 
> had no success finding
> any information on how to display historical METAR data on our ADDE server.

I am sorry that you spent so long looking for help.  Your experience is not the 
norm with users
of the webified email transactions.

One of the challenges you have been facing in your working with McIDAS is the 
fact that you have
not attended a training workshop.  A number of the questions you have asked in 
the various exchange
we have had are covered during the lecture and hands-on portions of the annual 
McIDAS training
workshop.

> I tried to setup a METAR dataset using
> DSSERVE ADD RTWXTEXT/SFCHOUSTO NCDF TYPE=TEXT 
> DIRFILE='/data/snapshot/20080204-07/ldm/mcidas/NetCDF/Surface_METAR*.nc' 
> INFO=/data/snapshot/20080204-07/ldm/mcidas/SAOMETAR.RAP "Real-Time SFC Hourly 
> Text - STO

First an observation and then a question:

- from the directory structure and name of the file in the DIRFILE= keyword for 
DSSERVE, I
  assume that the files to be included in the dataset are in netCDF

- if the observation is correct, then the TYPE= keyword you specify 'TEXT' is 
incorrect.  Only
  select types of grid and point data can be served from netCDF files.  The 
McIDAS HELP
  and Users Guide information for the DSSERVE command are very clear about 
this.  Here
  is the relevant portion of the McIDAS HELP command:

************************  netCDF Dataset Remarks  ************************
   You can access netCDF grid and point files in NCDF-format datasets
   created using DSSERVE with the TYPE, DIRFILE & INFO keywords.
   The TYPE keyword specifies the data type (GRID or POINT) of the netCDF
   files in the dataset. The DIRFILE keyword specifies the directory and
   file masks to locate the netCDF files. The INFO keyword specifies the
   name of the configuration file that maps the netCDF file parameter
   names to McIDAS parameter names. The configuration file must be
   tailored specifically to the netCDF files in the dataset. Two sample
   configuration files, named netcdfgrid.cfg and netcdfpoint.cfg, are
   available in the ~mcidas/data directory. Refer to those files when
   creating configuration files for your netCDF grid and point datasets.

  The McIDAS Users Guide page:

http://www.unidata.ucar.edu/software/mcidas/current/users_guide/DSSERVE.html#35904

  is also quite clear on how to define an ADDE dataset from data stored in 
netCDF files and
  gives a relevant example.

> Unfortunately when I try to execute the command "OBSRPT RTWXTEXT/SFCHOUSTO 
> ID=KPIT", I get the following error:
> OBSRPT: Dataset is not of the kind OBTX
> OBSRPT: Error getting data from server
> OBSRPT: done

Correct.  The type of the data is not TEXT, it is POINT.  The TYPE= keyword 
tells McIDAS
which server to run to get data out of the file(s).  The McIDAS TEXT server has 
no idea of
how to extract data out of a netCDF file.

> What am I doing wrong?

In a previous email, I alluded to the need to rename realtime MD (type POINT) 
files before they
get to be 10 days old.  Even though my comment was in regards to wind profiler 
data, the same
comment applies to decoded METAR data.  If you save off and rename the decoded 
daily MD files
for METAR data (MDXX0001 - MDXX0010), you can easily incorporate them into an 
ADDE dataset.
You would do this in the same way that you did for the decoded wind profiler 
data.

> Is there an easier way to serve NetCDF data thru ADDE?

Your dataset definition for the data was almost correct.  If you change 
TYPE=TEXT to TYPE=POINT
you will be closer to your goal of serving POINT data saved in netCDF format.  
The next
step, however, is the creation of a configuration file that will be used by the 
netCDF ADDE
server to map between variable names in the netCDF and variable names that 
McIDAS can understand.
The McIDAS distribution comes with two ** example ** files, netcdfgrid.cfg and 
netcdfpoint.cfg,
that one can use to create configuration files for GIRD and POINT data, 
respectively.  Please
remember that one should make a copy of the appropriate file AND RENAME THE 
COPY and then
edit the content to create needed name mappings.  I suggest, however, that your 
ultimate
goal should be the saving off of the decoded realtime data into renamed files 
and then
create an ADDE dataset that accesses those files.

> Do I need to run a decoder like nc2metar (the inverse of metar2nc)?

No.  The process of taking raw METARs and creating a dataset of TYPE=TEXT text 
is tricky.  It
requires quite a bit of knowledge of how the McIDAS decoders work and of the 
structure
for the TEXT data files.  I would only recommend this approach for a very 
experienced
McIDAS user.

> Is there a general tutorial on how to setup an ADDE server using different 
> data types?

I strongly recommend that you (re)read the Users Guide page and review the 
online HELP
for the DSSERVE.  Since you have not attended a McIDAS training workshop, it 
would be
most helpful to you to work your way through the online workshop materials:

http://www.unidata.ucar.edu/software/mcidas/current/workshop/toc.html

Cheers,

Tom
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Ticket Details
===================
Ticket ID: SXY-331778
Department: Support McIDAS
Priority: Normal
Status: Closed


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