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Hi Ken, > I just got the new version of IDL (3.6), which includes netCDF support on > the DEC Alpha OSF1 machines. There is a bug when reading LONG arrays into > IDL, i.e., > > Correct version (AIX) > > IDL> id=NCDF_OPEN(myfile) > IDL> NCDF_VARGET, id, 'ip', iparams > IDL> help, iparams > IPARAMS LONG = Array(18) > IDL> print, iparams > 1980 1 1 1 458 1980 > 1 31 31 488 0 12 > 12 32 32 128 128 16384 > > > Incorrect version (OSF1) > > IDL> id=NCDF_OPEN(myfile) > IDL> NCDF_VARGET, id, 'ip', iparams > IDL> help, iparams > IPARAMS LONG = Array(18) > IDL> print, iparams > 1980 0 1 0 1 0 > 1 0 458 0 1980 0 > 1 0 31 0 31 0 > > > As you can see, the correct values are interspersed with zeros, suggesting > some kind of 32/64-bit conversion error. Yes, apparently IDL is mapping netCDF `long's to C `int's rather than to the type `nclong' (which is currently a C `long' on the Alpha but which will eventually be changed to a C `int'). If they code such that the internal type `nclong' is used to hold values of external type NC_LONG, then this problem should disappear. In an earlier note I sent to RSI, I recommended this. >>Unfortunately we have JUST released a new version (3.6.1). Your bug report >>has been submitted to the development team and they will work on a fix >>for the next release. However if the source of the problem is >>with the developers of the NETCDF code, as we have seen many times, this >>takes some of the control out of our hands. I've looked through our support archives and found exactly one netCDF bug reported from RSI, and that was something we had already fixed and released in netCDF 2.3.2. RSI was apparently still using a much older version, more than a year after the release of netCDF 2.3.2. > Do you know of any such problems in the Alpha/OSF1 version of netCDF? Our currently released version netCDF 2.3.2pl2 passes the stringent testing in the nctest program on Alpha/OSF1. We know of no outstanding problems. -- Russ Rew UCAR Unidata Program address@hidden P.O. Box 3000 http://www.unidata.ucar.edu/ Boulder, CO 80307-3000