Re: [netcdfgroup] NetCDF4 problem

• To: Charlie Zender <zender@xxxxxxx>, netCDF Mail List <netcdfgroup@xxxxxxxxxxxxxxxx>
• Subject: Re: [netcdfgroup] NetCDF4 problem
• From: Antonio Rodriges <antonio.rrz@xxxxxxxxx>
• Date: Tue, 04 Nov 2014 15:04:14 +0200

Charlie, 

Can you describe what changed in your setup to produce correct chunking? Have 
you also tested Windows NCO?
-- 
Kind regards, 
Antonio Rodriges

 Charlie Zender <zender@xxxxxxx> 
>Group,
>
>Please ignore my warning on 20141029 about unreadable files after
>chunking with NCO, nccopy, and h5repack. Although chunking can create
>unreadable files in some circumstances, the specific problems that I
>reported were false positives, i.e., I incorrectly diagnosed them.
>NCO, nccopy, and h5repack work well for the examples given (below).
>An unlikely coincidence of issues fooled my diagnosis with ncwa.
>I'll try to be more thorough/careful before responding about potential
>problems on this list. Apologies for any inconvenience this caused.
>
>cz
>
>zender@roulee:~$ time ncks -O -4 --cnk_dmn latitude,4 --cnk_dmn 
>longitude,4 --cnk_dmn time,512 ~/2014.nc ~/2014_ch_ncks.nc
>real    2m27.044s
>user    0m39.915s
>sys     1m40.638s
>zender@roulee:~$ time nccopy -c time/512,latitude/4,longitude/4 
>~/2014.nc ~/2014_ch_nccopy.nc
>real    2m27.931s
>user    0m39.730s
>sys     1m42.749s
>zender@roulee:~$ ncks -O -4 ~/2014.nc ~/2014.nc4
>zender@roulee:~$ time h5repack -l u10m:CHUNK=512x4x4 -i ~/2014.nc4 -o 
>~/2014_ch_h5repack.nc
>real    0m2.907s
>user    0m0.479s
>sys     0m0.515s
>zender@roulee:~$ ncwa -O ~/2014_ch_ncks.nc ~/foo.nc
>zender@roulee:~$ ncwa -O ~/2014_ch_nccopy.nc ~/foo.nc
>zender@roulee:~$ ncwa -O ~/2014_ch_h5repack.nc ~/foo.nc
>zender@roulee:~$

• References:
  • Re: [netcdfgroup] NetCDF4 problem
    • From: Charlie Zender