Hi, On Mon, Feb 08, J-L Boers wrote:
/ PPS: Want some challenge? Find the formula that gives you a torus ;-)
It's pretty neat.The flat torus formula:
[u,v] -> [cos(u + v), sin(u + v), cos(u - v), sin(u - v)]/sqrt(2)
where u and v both run from zero to 2 pi. The sum of the squares of these four coordinates is 1 so the object is completely contained in the hypersphere of radius 1 centered at the origin in four-space.
Cute ;) But that's too easy. The question was meant to be: Find an equation f(x,y,z)=0 so that all solutions of the equation form the surface of a torus. To be honest: I don't know the solution. I even don't know if this equation exists ;) -o) Hubert Mantel Goodbye, dots... /\\ _\_v - To get out of this list, please send email to majordomo@suse.com with this text in its body: unsubscribe suse-linux-e Check out the SuSE-FAQ at <A HREF="http://www.suse.com/Support/Doku/FAQ/"><A HREF="http://www.suse.com/Support/Doku/FAQ/</A">http://www.suse.com/Support/Doku/FAQ/</A</A>> and the archiv at <A HREF="http://www.suse.com/Mailinglists/suse-linux-e/index.html"><A HREF="http://www.suse.com/Mailinglists/suse-linux-e/index.html</A">http://www.suse.com/Mailinglists/suse-linux-e/index.html</A</A>>