Re: udev and devfs - The final word

Vojtech Pavlik
2004-01-05T17:28:42Z

On Mon, Jan 05, 2004 at 08:13:26AM -0800, Linus Torvalds wrote:

> But the thing is, some things you simply _cannot_ number. For example, a
> two-dimensional space is innumerable - you need more than one integer
> number to look things up. So is the set of real numbers (but not the set
> of fractions), etc etc.

Two dimensional discrete space (*) is enumerable. Just start at [0,0]
and assign numbers going around the center in a growing spiral (**).
That way you assign a number to every point in that space. This is very
similar to the trick used to demonstrate fractions are enumerable.

(*) The one where you can use two integers to look things up.
(**) Assuming the coordinates can be negative. For non-negative
it's even easier.

--
Vojtech Pavlik
SuSE Labs, SuSE CR