Hi Hein:
The short answer is that you need to use CF Conventions, see Section 9
and Appendix H:
http://cf-pcmdi.llnl.gov/documents/cf-conventions/1.6/cf-conventions.html
John
On 3/5/2014 4:05 AM, Hein Zelle wrote:
Dear IDV users,
I have a problematic observation file which I can't open with
IDV. It is of the type "point" feature, and has a record axis
with independent observations. Each record has separate longitude,
latitude, time and data values.
The original file which _does_ work is here:
http://freja.argoss.nl/file-exchange/Surface_Synoptic_latest.nc
I have tried to compress the file by doing the following:
1) remove large variables
2) change record axis to a fixed axis
3) scale floats and ints to short
4) add netcdf4 format and compression
The resulting file is here:
http://freja.argoss.nl/file-exchange/test_packed_surface.nc
The result (< 1mb) is indeed much smaller than the original (23mb) and
contains identical thata for those variables I have kept. However:
Step 1 is fine, IDV reads the file.
Step 2 makes the file unreadable for IDV, although I don't see why it should.
Step 3 doesn't achieve compression without step 2
(netcdf pads variable records to 4 bytes)
Step 4 doesn't achieve compression without step 2
(variable records to small for compression algorithm)
Could anyone help me in making this file work in IDV?
I've tried to track down the source code in the java-netcdf source
code that reads point data files, but so far I didn't succeed. A
pointer to the right source file would be great, so I can try to
make it work.
Kind regards,
Hein Zelle
