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20000424: McIDAS netCDF image output form for DAY

>From: David Harper <address@hidden>
>Organization: NCAR/RAP
>Keywords: 200003012325.QAA04248 McIDAS-X GINI netCDF

Dave,

>We have been playing with the netCDF files and have run into a
>problem.  How easy is it to manipulate the output through McIdas?  We
>need to change the time into UNIX time.

Right now, there are no controls for the CDL of the output netCDF.
Here is some pertinent verbage from the routine that writes the netCDF:

** Remarks:
**
** This is an ADDE server which can be used to convert McIDAS area
** format data into NetCDF format.  Details about the implementation
** of this server follow.
**
** If the TRACE flag is set to some positive value on the command line,
** the server will write a log file to /tmp.  The file will be named
** by subserver name concatenated with the process id.  So an example
** log file might be called (absolute path) /tmp/ncdfaput25296.  This
** feature is purely for debugging purposes.
**
** As far as naming the output files, the current implementation just
** takes the output ADDE descriptor name, concatenates the position
** number padded to four leading digits, and adds a suffix of ".nc".
** So, for the following copy command:
**   IMGCOPY GOES8S/NH.-1 NCDF/GVAR.3 BAND=4
** the output file name would be GVAR0003.nc.
**
** The exact format of the output NetCDF file is certainly not carved
** in stone.  Which area metadata to include, how to format and store
** data and navigation, are all subject to debate.

>We can try running untilities
>on it to change the fields, but I wanted to try this avenue first.

Sorry, there are no command line flags to change the form of any
of the fields written to the netCDF.  I would have been nice if
the output routine used a user-defined CDL, but it doesn't.

>There may be more, but this was the first thing that killed Zebra.

If the time was a problem, I am suprised that the date was not also.
The format of the output date is currently CCYYDDD, where CC is the
century, YY is the last two digits of the year, and DDD is the Julian
day of the year.

>Thanks,

You could really install McIDAS and then modify the source code for the
netCDF file writer.  This way you could correct the problem at the source.

Tom

>From address@hidden Mon Apr 24 13:18:50 2000
>Subject: Re: 20000424: McIDAS netCDF image output form for DAY

Thanks for the info.  We decided to go with the utilities as it looks like we
only need to make minor changes.  The date can appearantly be read, by the way,
though once I get the rest patched in we'll see if it is in fact reading it
corretly.

Dave