Talk:Parametrization (geometry)

I more or less wrote this new version from scratch. Please feel free to improve it. There are plenty of avenues left to explore. Mike 22:48, 2 December 2007 (UTC)

proposed move

I plan to move this to parameterization. The content of the article predominantly uses this spelling, and a move would improve consistency.

If I hear no objections in 2 days, I'll go ahead and move it. —Preceding unsigned comment added by Shentino (talk • contribs) 02:23, 27 February 2008 (UTC)

It's been more than two days. I agree. Oxford English Dictionary, and Merriam Webster agree. For some reason my Linux spell checker doesn't like it, but too bad. I vote to move. Rkedge (talk) 18:43, 6 August 2018 (UTC)

Ten years is clearly more than two days :-) D.Lazard (talk) 20:37, 8 August 2018 (UTC)

Dubious claim

It's nonsense to claim that '-ise' endings are 'British English'. Oxford recommends '-ize' endings for all verbs not derived directly from the French - the latter having suffixes like '-cise' (exercise), -prise (comprise), -mise (compromise), etc. I'm deleting this all-too-common mistake. 82.46.70.132 (talk) 21:27, 18 March 2013 (UTC)

links on parametrization techniques

feynman and schwinger parametrization are not "parametrizations" in the sense discussed in the article. they are methods for solving integrals. --Nomadbl (talk) 15:14, 6 January 2014 (UTC)

I agree. In fact none of the techniques or examples (other than Boy's surface) is using the word parametrization to refer to the parametrization of a curve or surface.

From Examples:

McCullagh's parametrization of the Cauchy distribution is a parametrized family of distributions i.e. the parameters are not the argument of the function.

Parametrization (climate), Singular isothermal sphere profile, and (I assume) the Lambda-CDM model are using parametrization in this general sense, and not the geometric sense (as a local coordinate on some geometric object).

Boy's surface is referring to the parametrization of a surface, but it's unclear why this example was selected. There is no shortage of parametrized curves and surfaces to give as examples, and picking one that is more at the level of a vector calculus course (and not requiring knowledge of immersions and the real projective plane) would be more clear to non-mathematicians.

From Techniques:

As Nomadbl said, the Feynman and Schwinger parametrizations are not techniques for parametrizing curves or surfaces. As in the examples above, the solid modeling article refers to parameters in the more general sense (not in the sense of local coordinates). Dependency injection doesn't seem to be related at all.

For the examples section, I suggest a table identifying a few very basic curves and surfaces by name, each with a parametrization and a figure.

The technique section should probably just be removed completely. Nolan.King90 (talk) 02:10, 18 May 2024 (UTC)

recent edit

I added a few more details. But this page needs a lot more input. The physics / mathematics aspect would benefit from some concrete examples, with formulae and some nice figures. And where are the engineers? They have their own interpretation of parameterization which is quite different from that of physics. This is such an important topic, that deserves a more thorough treatment. Historians of science will no doubt have something interesting to say also. — Preceding unsigned comment added by Ibison (talk • contribs) 05:39, 17 June 2014 (UTC)

Parametrization: Why???

What is the reason for this proces? — Preceding unsigned comment added by Koitus~nlwiki (talk • contribs) 16:33, 30 May 2018 (UTC)

It is simply that explicit functions are much easier to manipulate than implicit functions. However I agree that this should be said in the lead. D.Lazard (talk) 17:57, 30 May 2018 (UTC)

curve

hello friends, i encountered → a second revert today after having modified the animation and replaced it by a much leaner GIF sequence with thicker curves. the reason for the revert was a) the edge at the bottom left and b) the left curve being "not parametrizised". well, i'm used to the terminology of my 3D animation program Autodesk Maya where a motion along a curve either respects the distribution of the NURBS CVs or not. left cube, and that's the reason for the corner i created, moves at the same speed from beginning to end and around that corner. the right cube respects the CVs: it moves much slower when the density of those "Control Vertices" is strong. best, Maximilian (talk) 13:22, 19 December 2018 (UTC)

On my browser, the image displays as two grey right angles on a black background, with 8 red points similarly placed on each right angle. When the animation starts, a solid square move on each right angle, at a constant speed on the left, and at a variable speed on the right. Nothing else. No indication on what is parametrized. No indication on how this is related to the content of the article. Above comment does not clarify anything. Apparently, the only relationship between this article and the animation is that "parametrization" seems a term of Maya's jargon. As Wikipedia is an encyclopedia, such a specialized jargon has not its place outsides articles devoted to Maya. For making this animation acceptable in Wikipedia, you must 1/ provide a understandable explanation that it illustrates the content of the article 2/ provide a WP:reliable source for this explanation 3/ convince other editors that the animation is useful for the article. D.Lazard (talk) 17:58, 19 December 2018 (UTC)

thanks, and no worries. i won't put more effort into this. parametrizsation is a common term all over computer graphics, not only in Maya. the parametrizsation of NURBS surfaces and curves is so central to CGI that the distribution of curves on a surface (such as the fender of a car) are called "isoparms". i studied maths, so i know about hermetics. the discussion page of the german article about mathematical parameters is full of complaints by students and teachers that it is too abstract. btw: strange that you don't see the thick grey lines. i rendered the scene with motion blur and subtile shadows. displays nicely here in firefox. Maximilian (talk) 22:45, 19 December 2018 (UTC)

To editor Maximilian Schönherr: I have moved Parametrization to Parametrization (geometry), and Parametrization is now a disambiguation page. So, there is now a natural place for creating articles such as Parametrization (computer graphics). When created, such an article must clearly be linked in Parametrization. D.Lazard (talk) 11:50, 20 December 2018 (UTC)