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Harsh, > To: address@hidden > cc: address@hidden, > cc: address@hidden > From: Harsh Anand <address@hidden> > Subject: netCDF and NC_MAX_VARS=2000 limitation > Organization: Lawrence berkeley National Laboratory > Keywords: 200103270213.f2R2DwL14596 The above message contained the following: > Some of the netCDF library users at NERSC are finding it hard to > work within the maximum number of variables limit (NC_MAX_VARS=2000) > imposed in current version of NetCDF. Is it possible to raise > the NC_MAX_VARS limit in the future releases of NetCDF library? > > > I realize that we could locally build a version of NetCDF with a raised > > NC_MAX_VARS, here at PPPL, but we would risk losing the binary portability > > of our files, which is the whole motivation for using NetCDF in the first > > place. (We pass these files, which contain close to 2000 variables and > > are of order 50Mbytes large, amongst collaborators, many of whom have > > their own NetCDF installations not controlled by us). Or, we could break > > up our files or consolidate multiple variables into a singly named multi- > > dimensional glob of numbers, but these types of solutions would impose > > lasting inconvenience on our users. > > > > We think the cleanest solution (for us, at any rate) would be if NetCDF > > would allow a higher limit on the total number of variables per file. > > > > At the level we are using it (aside from this NC_MAX_VARS limit which > > has tripped us only once, recently), we find the robustness, portability, > > and performance aspects of NetCDF all to be excellent. But we expect, > > with the development of our code, for NC_MAX_VARS=2000 to become an > > intolerable limitation at some point in the not too distant future. > > Thanks. > > Harsh Anand > > Harsh Anand ---------------------------------- address@hidden -| > NERSC User Services phone: (510) 486-5575 | > Lawrence Berkeley Lab Fax: (510) 486-7202 | > Univ. of California, Berkeley ------------------------------------ We'll have to discuss it. I think we could do it tomorrow if not for the Fortran-77 interface. I believe the problem is that that interface allocates static storage based on NF_MAX_VARS (the Fortran equivalent to NC_MAX_VARS). Raising it might put an unreasonable and unnecessary burder on some programs. I'll discuss it with Russ when he returns from vacation. Regards, Steve Emmerson <http://www.unidata.ucar.edu>