Talk:Toroid

Topology and... Patents?!

Why is it that there are two US patent links in a topology article?--189.101.47.206 (talk) 03:52, 12 April 2009 (UTC)[reply]

I see no reason to have them here. I don't see how they relate to the topic. --Ronz (talk) 16:50, 22 October 2009 (UTC)[reply]

Idea for expansion

Perhaps someone could write in about how to calculate the volume of a toroid? - i.e. Using the formula for a solid of revolution? http://en.wikipedia.org/wiki/Solid_of_revolution — Preceding unsigned comment added by Tomthecool (talk • contribs) 20:49, 5 April 2011 (UTC)[reply]

Conflicting definition?

This article says that a toroid is like a torus except that it is created by rotating any shape around an axis, while a torus is a special case where the rotated shape is a circle. The Torus page, as well as the Toroid_(disambiguation) page, both state that a toroid is the solid bounded by a torus (ie that a torus is the surface of a toroid). From looking around on the internet I can't tell for sure whether there are two different meanings of the word or just a lot of incorrect assumptions. Is one of these definitions incorrect or are there two accepted meanings for Toroid? MichaelBoon (talk) 21:29, 16 January 2012 (UTC)[reply]

Propose redirecting to surface of revolution

Does this article really stand up? There is a disambig page for the adjective Toroidal, with circular linking between it and Toroid (disambiguation). Outside of Stewart's toroidal polyhedra, which Stewart calls toroids, any higher-genus manifold is described by mathematicians as a torus and I can find no suggestion that a toroid is anything other than a particular class of a surface of revolution.

I do not think there can ever be enough material to sustain this page as a standalone article. It needs to be merged into its primary article and redirected. The obvious first choice might be torus, but I think that surface of revolution is more accurate. Does anybody have any objections? — Cheers, Steelpillow (Talk) 13:02, 22 November 2015 (UTC)[reply]

Sounds good to me, unless other sources can be found. The MathWorld article says surface of revolution. Tom Ruen (talk) 02:36, 23 November 2015 (UTC)[reply]
I notice the rings of polyhedra in 4D polytopes are called tori despite being discrete, although I guess the vertices exist on a flat torus "surface". I can see a class of 4D toroids would have a polygonal cross section, and continuous screw axis rotation along with the revolution, basically a double rotation with object offset from one axis. Tom Ruen (talk) 02:42, 23 November 2015 (UTC)[reply]

surface of revolution is very unspecific compared to toroid. A toroid is a body, I would not search for it under any surface. Ra-raisch (talk) 15:05, 23 September 2017 (UTC)[reply]

Bad writing

The second paragraph of the article is as follows:

"'The term toroid is also used to describe a toroidal polyhedron. In this context a toroid need not be circular and may have any number of holes. A g-holed toroid can be seen as approximating the surface of a torus having a topological genus, g, of 1 or greater. The Euler characteristic χ of a g holed toroid is 2(1-g)."

It is unfortunate that the word "toroid" is defined in this case in terms that use the word "toroidal" in them. Nobody knows what a "toroidal polyhedron" is.

Also, nobody has the vaguest idea what kinds of holes are referred to in the statement:

"In this context a toroid need not be circular and may have any number of holes."

It is also completely unclear what the word "approximating" means in the next sentence:

"A g-holed toroid can be seen as approximating the surface of a torus having a topological genus, g, of 1 or greater."

Also, the word "torus" in this last sentence is used erroneously.

In short, the writing is so bad that nobody reading this will have any idea of what it means. 2601:200:C000:1A0:A102:CA1D:93C6:F190 (talk) 21:21, 15 January 2022 (UTC)[reply]