Hi,
sorry that I have not been clearer, but my main complaint is that
> NetCDF: Invalid argument
> Location: file nccopy.c; line 637
isn't a useful feedback to a user trying to chunk some dimensions.
I think it is caused by nccopy using 0 (NC_UNLIMITED) as default for
unlimited dimension which doesn't work for chunking. 1 or anything else
would be much, much better than 0.
In my world of operational meteorology, file-formats change very slowly
- a default of 1 is very similar to what netcdf-3 has been doing with
unlimited dimensions and it won't surprise users as a default.
Best regards,
Heiko
On 2014-10-23 16:22, Ed Hartnett wrote:
This gives very poor performance when the number of timesteps in the
file is large.
On Thu, Oct 23, 2014 at 5:25 AM, Heiko Klein <Heiko.Klein@xxxxxx
<mailto:Heiko.Klein@xxxxxx>> wrote:
Hi,
when chunking files with unlimited dimension, the unlimited
dimension must be given explicitly in nccopy, and will usually be
set to one.
In a file with time as unlimited dimension, and X and Y as
dimensions, it is currently required to use
$ nccopy -k 4 -c "time/1,X/100,Y/100" in.nc <http://in.nc> out.nc
<http://out.nc>
When running without time, it does not work:
$ nccopy -k 4 -c "X/100,Y/100" in.nc <http://in.nc> out.nc
<http://out.nc>
NetCDF: Invalid argument
Location: file nccopy.c; line 637
Only for unlimited dimensions, one needs to give the dimension
explicitly, for all other dimensions a useful default (full
dim-size) is used. I think a useful default for unlimited dimensions
is 1.
Heiko
--
Dr. Heiko Klein Tel. + 47 22 96 32 58
<tel:%2B%2047%2022%2096%2032%2058>
Development Section / IT Department Fax. + 47 22 69 63 55
<tel:%2B%2047%2022%2069%2063%2055>
Norwegian Meteorological Institute http://www.met.no
P.O. Box 43 Blindern 0313 Oslo NORWAY
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--
Dr. Heiko Klein Tel. + 47 22 96 32 58
Development Section / IT Department Fax. + 47 22 69 63 55
Norwegian Meteorological Institute http://www.met.no
P.O. Box 43 Blindern 0313 Oslo NORWAY
