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Randy, >Date: Mon, 16 Mar 1998 16:25:27 -0500 >From: address@hidden (Randy Zagar) >Organization: . University of Delaware/College of Marine Studies >To: address@hidden >Subject: Re: 980121: NetCDF-3.3.1 and fortran compiler option -U >Keywords: 199803162125.OAA27405 In the above message, you wrote: > 1. A *long* while back, I mentioned that I/we were having problems > compiling a CFD model with NetCDF because its' Makefile insisted > on using a '-U' option to preserve the case of all the symbols... > > The recommended course of action we came up with was to take all > the symbol names in "netcdf.inc" and make them lower-case to > match what was in the library. This has also been done in the latest netCDF release (3.4). > I can confirm that this works and, furthermore, does not seem > to interfere with anything else I've written... The URL for > the "netcdf.inc" I am now using is: > > ftp://newark.cms.udel.edu/pub/users/zagar/netcdf.inc > > > 2. Onto another issue entirely... I recently solved a problem I've > been having with 'packed' variables. I'm writing Perl programs > to convert datafiles to NetCDF, and in some cases it's appropriate > to store the data as 'BYTE' or 'SHORT' and have the 'scale_factor' > and 'add_offset' attributes as 'FLOAT'. > > The documentation says that 'valid_min', 'valid_max', and > 'valid_range' should be the same type as the packed variable, > but I find it convenient to make them the same type as the > 'scale_factor' and 'add_offset' attributes... > > From what you've seen, which way do other NetCDF developers > handle this issue ? I haven't seen very much of the work of other netCDF developers, so I don't feel qualified to comment on this issue. You might try posting this question to the netcdf mailing-list. > Am I begging for trouble if I continue doing it this way ? > > Lastly, the documentation doesn't address the '_FillValue' > attribute in the context of 'packed' variables. It has taken > me two days to discover that '_FillValue' *must* be the same > type as the unscaled variable and *NOT* the same as that for > 'scale_factor' and 'add_offset'. It wouldn't be difficult to > mention this in the docs. > > > 3. Adding a -perl option to 'ncgen' would be *wonderful*... I'll pass that on. > > > Anyway, NetCDF is great stuff. You guys are doing great work and I > just wanted to know that I *really* appreciate your efforts. Thanks. > > > -Randy > > > > p.s. While composing this e-mail, it occurred to me that the whole > concept of a products' learning curve is a lot like Sissiphus > in Greek mythology. By the time you get the rock up the hill, > they've changed the standard on you and you have to do it all > again... Thankfully, NetCDF isn't written by Microsoft. > > === > > Randy Zagar E-Mail: address@hidden > Sr. Scientific Programmer E-Mail: address@hidden > College of Marine Studies Voice: (302) 831-1139 > University of Delaware FAX: (302) 831-6838 > Newark, DE 19716 -------- Steve Emmerson <http://www.unidata.ucar.edu>