Re: How long is a hz?

Sean Bruno wrote:
Jason Slagle wrote:
On Mon, 28 Jan 2008, Sean Bruno wrote:

I couldn't quite find the definition for "hz" in sys/ this morning. What is it's value and where is it defined?

From http://en.wikipedia.org/wiki/Hertz

The hertz (symbol: Hz) is the International System of Units (SI) base
unit of frequency. Its base unit is cycle/s or s^-1 (also called
inverse seconds, reciprocal seconds). In English, hertz is used as both
singular and plural. As any SI unit, Hz can be prefixed; commonly used
multiples are kHz (kilohertz, 10^3 Hz), MHz (megahertz, 10^6 Hz), GHz
(gigahertz, 10^9 Hz) and THz (terahertz, 10^12 Hz).

One hertz simply means one cycle per second (typically that which is
being counted is a complete cycle); 100 Hz means one hundred cycles per
second, and so on. The unit may be applied to any periodic event--for
example, a clock might be said to tick at 1 Hz, or a human heart might
be said to beat at 1.2 Hz. The frequencies of aperiodic events, such as
radioactive decay, are expressed in becquerels.


But more importantly, where is "hz" defined in the kernel tree?

Sean
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http://fxr.watson.org/fxr/ident?i=hz
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