time axis in multi-netCDF

[Jörg Kaduk <joerg@xxxxxxxxxxxxxxxxxxx>]

Hi,

I have the following problem:

I have a couple of files which contain half hourly data for each month.
Since the data are from observations they start at some arbitrary time.
So my Feb. file starts on Feb. 3 at 15:30
The files for the remaining months of the year have data for each half
hour.
I would like to treat all files as a multi netCDF file. To test the
setup
I started with only the Feb file:
That's my descriptor:

1 ****************************************************************
* NOAA/PMEL Tropical Modeling and Analysis Program, Seattle, WA. *
*           created by MAKE_DESCRIPT rev. 4.01                   *
******************************************************************
 $FORMAT_RECORD
  D_TYPE               = '  MC',
  D_FORMAT             = '  1A',
  D_SOURCE_CLASS       = 'WRCCRF data',
 $END
 $BACKGROUND_RECORD
  D_EXPNUM             = '0000',
  D_MODNUM             = '  AA',
  D_TITLE              = 'WRCCRF observational data',
  D_T0TIME             = '03-FEB-1998 15:30:00',
  D_TIME_UNIT          =  1800,
  D_TIME_MODULO        = .FALSE.,
 $END
 $MESSAGE_RECORD
  D_MESSAGE            = ' ',
  D_ALERT_ON_OPEN      = F,
  D_ALERT_ON_OUTPUT    = F,
 $END
*************************************************
 $EXTRA_RECORD
 $END
  $STEPFILE_RECORD
   s_filename           = 'sta02_1998.001',
   S_AUX_SET_NUM        = 0,
   S_START              = 33.6458,
   S_END                = 58.9792,
   S_DELTA              = 0.0208333333333,
   S_NUM_OF_FILES       = 1,
   S_REGVARFLAG         = ' ',
  $END
**************************************************
 $STEPFILE_RECORD
  s_filename           = '**END OF STEPFILES**'
 $END
**************************************************


Now, the time units in the netCDF file are "days since 01-JAN-1998
00:00:00"
ferret reads the file fine and complains:
 WARNING - NON-INTEGER NUMBER OF STEPS PER STEPFILE
 INDICATED IN DESCRIPTOR - TRYING TO CONTINUE ANYWAY
But I think, that's ok, since the division (S_END-S_START)/S_DELTA
does not give an integer result. Ferret sets the correct number
of data records.
If I plot a variable, ferret plots all values fine, but the time 
axis runs only from 8 am on Feb 4 to 9 pm on Feb 4.

Did I set a value in the descriptor file incorrect? Which one?
I tried a couple of things, but it would not get me the correct
labeling of the time axis.
Any help greatly appreciated!

Thanks!
Joerg





--
Jörg Kaduk                            Tel.: 1 650 325 1521 x 416
Carnegie Institution of Washington    FAX: 1 650 325 6857
Dept. of Plant Biology
260 Panama Street                     joerg@jasper.stanford.edu
Stanford, CA 94305-1297               http://Jasper.Stanford.EDU/joerg/