[netCDF #IIL-400949]: Problem in opening large NetCDF

Hello,

The netCDF 4.1.1 release is fairly old and there are known issues with it and 
large file support on Windows.  Your best bet will be to update to a more 
recent release; the current release is 4.3.3.1, and should handle large files 
on Windows without issue.  I'm not familiar with IDL, but they may be able to 
provide guidance for linking against a newer netCDF library.

I hope this helps,

-Ward

> Hello,
> 
> I contact you about an issue in my NetCDF manipulating. Firstly I am
> working under Windows 7 64bits and with IDL 8.3. The NCDF library is the
> 4.1.1.
> I already search in the forum, on the internet, on your website,
> FAQ...but I didn't find any answers to my problem or the question are a
> little bit different.
> 
> I need to store a 432* 2 209 000 array in the NCDF file. It works a
> priori, I mean the file i written on the the disk and it is about 7.37
> or 7.47Go (depending on the format used : /NETCDF3_64bits or
> /NETCDF4_FORMAT. The variable is written in separate time, in a loop
> like that :
> 
> "
> id = ncdf_create(filename,/clobber,/NETCDF4_FORMAT);/NETCDF3_64BIT);)
> dim_cdf_spect = ncdf_dimdef(id, 'Spectral dim',432)
> dim_cdf_sptl = ncdf_dimdef(id, 'Spatial dim', /UNLIMITED)
> IoF_big = ncdf_vardef(id, 'DATA',[dim_cdf_spect,dim_cdf_sptl],/double)
> ncdf_control, id, /ENDEF ; put the file into data mode
> 
> for i... do begin
> 
> ...computing some stuff
> 
> if i eq 0 then begin
> NCDF_VARPUT,id,IoF_big,IoF ; this is for the first iteration
> off = sptl_dim
> endif
> if i ne 0 then begin
> NCDF_VARPUT,id,Iof_big,IoF,offset=[0,off] ; where off is the
> offset, the size of second dimension of the big array
> off = sptl_dim+off
> endif
> 
> NCDF_CLOSE,id
> "
> 
> This syntax works but the problem is to read the file. If it is lower
> than 2Go I can read it and extract the data. But if the size is greater
> than 2Go I can't do anything and when I execute this :
> 
> "
> Result = NCDF_OPEN(File,/nowrite) ; where file is the filepath of the .nc
> "
> 
> IDL returns:
> "
> NCDF_OPEN: Unable to open the file
> "C:\Users\Batiste\Desktop\08-test\IoF_M_big_solo_MTP006_to_MTP0114.nc".
> (NC_ERROR=-51)
> "
> 
> So the error code is -51 corresponding to an non-CDF file...which is I
> don't understand. I try also to read the file with H5 procedures
> (relative to (HDF file)) but I just can OPEN the file and can't go
> further...
> 
> Have you an idea of this problem ?
> 
> Thanks in advance.
> Best regards,
> Batiste Rousseau
> 
> --
> Batiste Rousseau
> 
> PhD Student - Planetary sciences
> LESIA - UMR 8109 - Observatoire de Paris, section de Meudon
> Bât. 17, bureau 34 - +33 (0)1 45 07 76 66
> 5, place Jules Janssen
> 92195 Meudon Cedex
> 
> 
> ---
> L'absence de virus dans ce courrier électronique a été vérifiée par le 
> logiciel antivirus Avast.
> https://www.avast.com/antivirus
> 
> 


Ticket Details
===================
Ticket ID: IIL-400949
Department: Support netCDF
Priority: Normal
Status: Closed