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>To: <address@hidden> >From: "Jeremy Cothran" <address@hidden> >Subject: time conventions >Organization: UCAR/Unidata >Keywords: 200212211725.gBLHPHt21606 Hi Jeremy, > I've been looking through the netCDF documentation trying to find if > there is a standard, well-supported way of defining a delta > time(delta_t) for netCDF files so that I don't have to articulate each > regularly spaced time instance. I have seen the attributes init_time > and delta_t used in some of the header files, but when I try to use > this with a utility like ncBrowse, it does not understand the > convention. I'd like to use my netCDF files with DODS servers and > other netCDF utilities(NCO for instance), but I'm unsure which time > conventions are generally supported and which are particular to a given > user/group. Unfortunately, there is no universal delta time convention for netCDF that is supported by DODS servers and netCDF utilities. The closest thing there is to a standard way of representing time in netCDF files is the use of the udunits conventions as described here: http://www.unidata.ucar.edu/staff/russ/netcdf/time/recs.html There are also some links in the FAQ document under the question "What is the best way to handle time using netCDF?": http://www.unidata.ucar.edu/staff/russ/netcdf/faq.html#time But these don't really address the delta_t question, which is discussed, but not settled, in the following postings: http://www.unidata.ucar.edu/staff/russ/netcdf/time/0031.html http://www.unidata.ucar.edu/staff/russ/netcdf/time/0032.html --Russ _____________________________________________________________________ Russ Rew UCAR Unidata Program address@hidden http://www.unidata.ucar.edu