Re: netCDF time representation

Steve Emmerson (steve@unidata.ucar.edu)
Wed, 12 Feb 92 10:21:10 -0700

>Here are a few examples of data requiring more than 32 bits of precision and
>the measurement time to reach the IEEE 64-bit double precision:

(Fascinating table omitted)

Remember, however, that we're talking about accessing such datasets via
a computer. A netCDF object that contained over 2^53 observations
would require quit a bit of storage (by my estimation, at least 10
petabytes (10^15 bytes)). Since the largest, extant mass storage
systems are only in the single terabyte range (10^12 bytes) and since
planned storage systems (e.g. the Sequoia 2000 project) are only in the
100 terabyte range, I think we can safely rule-out (for the moment
anyway) a requirement for representing more than 2^53 observations.

>I am a new user of netCDF. I was attracted to it because it had no inherent
>properties dedicated to a particular discipline, like FITS, for example.
>I hope the developers keep this discipline-free attribute ranked high as they
>decide how to improve a useful system.

"Discipline-freedom" is one of our goals; ease and convenience are two
others. User-feedback is still another. Please let us know if you feel
we have overlooked anything.

Steve Emmerson <steve@unidata.ucar.edu>