Options for HDF and units

[M.Mahakur]

GrADS Users:

I  created a ctl for the HDF (Gridded) data file. But, it shows entire
domain as undefined!! The data is "16 bits signed short integer". What
should I write in the ctl for 'OPTIONS' and 'variable units' for
non-standard binary (as I guess I have to treat like non-standard
binary!!).

The No. of lats and lons are 3275 and 3222. I feel the file size should
be 21104100 bytes (=3275*3222*2). However, the actual file size is
21106990 i.e. 2890 extra bytes. Is this because of some 'HEADER' inside
the HDF data file?

I had mentioned earlier I could NOT open using 'sdfopen'.

Thanks.

With Regards,

M. Mahakur

P.S. : I am using the following as ctl:

DSET ^test.HDF
DTYPE hdfsds
UNDEF -1.0E-33
XDEF  3275  LINEAR 68.1442 0.008928571
YDEF  3222 linear 6.74583 0.008928571
TDEF  1 LINEAR 01apr1998 1dy
ZDEF  1 LINEAR 1 1
VARS 1
npp -1,40,2,-1 0  NPP
ENDVARS