Re: Multiple netCDF datasets

[Joerg <joerg@xxxxxxxxxxxxxxxxxxx>]

Hi Carlos and all other ferreter's,

>Hi all,
>I have a time-series of climate data split in some netCDF files (i.e.
year1.nc
>year2.nc ....), and I would like to treat them as a single file in Ferret.
I've
>read in the Ferret documentation about the MC datasets (that seems to be
what I
>really need), but I heven't found any deep explanation about its usage
>
>Could anybody tell how can I make the MC descriptor of these files? Is there
>any other (easy) solution?
>
>Thanks in advance!
>

I've pasted below a part of the multi-netcdf descriptor file, sib_nc_qp2.des,
I made from an example which comes with ferret and which worked fine for me. 
In this case I use the descriptor file to read data from 12 monthly files.
I most definite used only a very limited set of the options which are 
available.
Check out the readme file README_about_mc_datasets and also there should
be a mc_datasets.tar to look into for examples. There is somewhere an
annotated TMAP descriptor file which explains a lot of options ( grep for 
annotated ).
Note, that the namelist syntax you need for the descriptor file is somewhat
picky and also machine dependent - I believe. I found the one below to
be working on our sun. Note the "1" in the first line. I think you may need
it.
It may not be in all examples which come with the me_datasets file,
persumably because not all machines require it. You may have to experiment a
bit. Or check out a handbook for you fortran compiler or ask a fortran guru
at your place.
Now, I'm certainly a total beginner with the descriptor stuff but this will 
hopefully be a start. 

Finally I would like to thank the ferret folks for this MC stuff. I find this
absolutely great! Really.

Good luck,

Joerg


1 *************************************************************************
*     NOAA/PMEL Tropical Modeling and Analysis Program, Seattle, WA.      *
*                  created by MAKE_DESCRIPT rev. 4.01                     *
*************************************************************************** 
* modified for SiB model output
 $FORMAT_RECORD
  D_TYPE               = '  MC',
  D_FORMAT             = '  1A',
  D_SOURCE_CLASS       = 'MODEL OUTPUT',
 $END
 $BACKGROUND_RECORD
  D_EXPNUM             = '0000',
  D_MODNUM             = '  AA',
  D_TITLE              = 'SiB model output',
  D_T0TIME             = '00-JAN-1981 00:00:00',
  D_TIME_UNIT          = 86400,
  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           = 'hsib_1981.qp2.nc.001',
  S_AUX_SET_NUM        = 0,
  S_START              = 15.5,
  S_END                = 15.5,
  S_DELTA              = 1,
  S_NUM_OF_FILES       = 1,
  S_REGVARFLAG         = ' ',
 $END
 $STEPFILE_RECORD
  s_filename           = 'hsib_1981.qp2.nc.002',
  S_AUX_SET_NUM        = 0,
  S_START              = 45,
  S_END                = 45,
  S_DELTA              = 1,
  S_NUM_OF_FILES       = 1,
  S_REGVARFLAG         = ' ',
 $END

................... more like this - files 03-11 .................

 $STEPFILE_RECORD
  s_filename           = 'hsib_1981.qp2.nc.012',
  S_AUX_SET_NUM        = 0,
  S_START              = 349.5,
  S_END                = 349.5,
  S_DELTA              = 1,
  S_NUM_OF_FILES       = 1,
  S_REGVARFLAG         = ' ',
 $END
**************************************************
 $STEPFILE_RECORD
  s_filename           = '**END OF STEPFILES**'
 $END
**************************************************

--
Jörg Kaduk                           phone:  +1 (650) 325 1521 ext 416
Carnegie Institution of Washington   fax:    +1 (650) 325 6857
Department of Plant Biology
260 Panama Street                    e-mail: joerg@jasper.stanford.edu   
USA - Stanford, CA 94305