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Re: netCDF time representation

Steve Emmerson (steve@unidata.ucar.edu)
Wed, 12 Feb 92 07:48:55 -0700

>Here are a few examples of data requiring more than 32 bits of precision:
>
>1. Radio pulsar timing --- 0.1 microseconds over years
>2. Astronomical X-ray data --- 0.01 microseconds over years
>3. Planet Ephemerides --- 1 microseconds over decades
>4. Laser/Atomic Spectroscopy --- 0.1 femtoseconds over milliseconds
>5. Fusion --- 1 nanoseconds over seconds
>6. Neutrino detection --- 1 millisecond over decades
>
>=Fred Knight (INTERNET:knight@ll.mit.edu)

Excellent! Thank you!

I might add that Mitch Baltuch, a Unidata colleague, informed me that
lightening data requires microsecond resolution over years.

Now, does anyone know of any datasets requiring more than 54* bits of
precision? This is approximately equivalent to microsecond resolution
for 600 years.

You'll see why I ask this question in my reply to Daniel Packman's
article about "base arithmetic".

--Steve

* 54 is the number of bits in the mantissa of an IEEE double.

 
 
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