File talk:Pi-unrolled-720.gif

Pause/Stop
This is an excellent animation. BirdValiant 18:36, 8 October 2006 (UTC)

Would it be possible to have the wheel pause after completing one whole turn, so that it emphasises the fact that the marker on the rim touches the ground at zero and pi? Maelin (Talk | Contribs) 10:14, 30 October 2006 (UTC)

I think that's what the line going around the wheel is for. BirdValiant 03:27, 3 November 2006 (UTC)


 * Yes, but it happens too quickly to see that the line is unravelling. If the wheel paused for a moment after completing the whole turn, it would be more obvious what had happened. Maelin (Talk | Contribs) 05:53, 7 November 2006 (UTC)
 * My opinion is that by making the wheel stop, the fluidity of the animation is ruined. Maybe the line could be thicker, or somehow have more contrast than it already has. Or, the blue marker on the rim of the wheel could be remain in place at the instant it reaches pi, while still retaining the marker on the wheel itself.  This extra blue mark might further emphasize that the marker touches at both 0 and pi, not that this isn't already obvious with the yellow and purple markers below.  BirdValiant 02:50, 8 November 2006 (UTC)


 * I made an altered version here. I've asked around a few friends and everyone seems to think the pause makes it clearer what the illustration is trying to show. Fluidity isn't really what's important, it's clarity. Maelin (Talk | Contribs) 07:31, 8 November 2006 (UTC)


 * Well, it's rather too late to discuss, but I think the pause is more helpful. This animation moves too fast. Otherwise, it's a great animation. --Fbv65 e del / ☑t / ☛c || 05:38, 20 January 2007 (UTC)


 * I just came here to comment that the animation is too fast, and have now seen Maelin's altered version. The pause is definitely a big improvement. Maelin, you should be bold and replace the existing image. I don't think anyone will have a good reason to complain. &mdash; Hex    (❝  ?!  ❞)   11:00, 1 April 2007 (UTC)


 * I second your comment, two years later. My immediate reaction to the original image was that it's brilliant, but much too fast. It would be much easier to follow if it were perhaps 30% slower. At either speed, though, the pause is a huge improvement. Since the article still has the original one, would anyone mind if I swapped in Maelin's improved version, or is this an area of controversy? (I don't mean controversy over whether it could be made even better, just whether this version is better than that one.) Michael Geary (talk) 02:08, 18 April 2009 (UTC)

Hey, I agree, this a brilliant animation. It explains pi perfectly even for a dummy like me that can't do maths. ^_^--62.31.12.18 01:55, 20 January 2007 (UTC)

Good illustration! However, I would have the wheel and the animation just stop after one complete revolution. That would be the clearest in my opinion. ●DanMS 05:56, 20 January 2007 (UTC)


 * Briliant! :) ---J.S (T/C/WRE) 06:49, 20 January 2007 (UTC)

Way too cool but
Bravo! However, is the diagram accurate? It seems to suggest that pi = perimeter. __earth (Talk) 11:20, 20 January 2007 (UTC)
 * actually, i take that back. __earth (Talk) 11:46, 20 January 2007 (UTC)

I agree with OP, this is a confusing diagram
For example 1 degree of a circle = pi/180 radians, and 1 radian = 180/pi degrees which goes to say that the circumference of a circle is theoretically 2pi, unless you are planning to completely alienate trigonometry from this topic.

Correct me if I am wrong.

Thanks — Preceding unsigned comment added by Aneeshpanoli (talk • contribs) 22:46, 22 March 2012 (UTC)

can I?
Can I use this on my userpage? —The preceding unsigned comment was added by Ootmc (talk • contribs) 21:12, 3 April 2007 (UTC).
 * Yes! You can use any image that is not licensed under "fair-use" on your userpage. This image is licensed under the GFDL, which basically means that you can use it in any way you want as long as any copies or things you make from it are licensed under the GFDL also. The copyright of the image is indicated under the "licensing" section of the image description page. You can read more about image copyrights on Wikipedia at Copyrights and Image copyright tags. You can read more about what you can do with your userpage at User page. -- BlastOButter42 See Hear  Speak 04:13, 6 May 2007 (UTC)

The diameter/circumference relation should be emphasized more clearly in the animation, like the fact that the diameter of the circle is 1. There is nothing in the animation that points to this relation which is, of course, the whole meaning of pi. —The preceding unsigned comment was added by Special:Contributions/ (talk)

I disagree completely with the above comment (that it is unclear that the diameter of the circle is 1) - the "intro" of the animation quite clearly shows, that the circle "fits" between the 0 and the 1 on the axis. This shows that the diameter is indeed 1. 212.242.167.26 (talk) 11:55, 25 March 2008 (UTC)
 * Actually, I just noticed that the first four whel=els are slightly shorter that the rolling wheel. A little error like that can throw the whole thing off. &mdash; Coasterge ekperson 04 ' s talk @May/07/08 13:22

SVG?
Why should this image be converted to SVG? I know SVG can be animated via Javascript but that needs a browser/rendering engine that can cope with that. I doubt the library WP uses to convert SVG to PNG actually is able to convert the animation into an animated GIF viewable for most people. So basically we'd lose the animation which is actually the defining part of this image. --Johannes Rössel (talk) 21:34, 18 June 2008 (UTC)


 * Because SVG is awesome. SVG animation does not require javascript, so it should be possible to easily convert an animated SVG to an animated GIF: http://www.w3.org/TR/SVG11/animate.html#AnimateElement  Excellent question. --Darxus (talk) 13:58, 20 August 2009 (UTC)


 * "It should be possible" is pure theory, what we need is actual working software. Here's a project for you: find (or write) a replacement for the rsvg library that supports SMIL and GIF, persuade MediaWiki developers to use it instead of rsvg, and then it might make sense to reimplement this image in SVG. — Emil J. 14:49, 20 August 2009 (UTC)


 * Most browsers support SVG animation nowadays. IE9 supports javascript animations (not standard animations though). — Preceding unsigned comment added by 161.116.12.130 (talk) 20:57, 2 November 2011 (UTC)

Amazing
The best animation I've ever seen. After 25 years, I finally understand what Pi is!! Now someone explain what e, and natural logs are. :) =Nichalp   «Talk»=  12:58, 15 August 2008 (UTC)

Radians
This would lend itself better to people's understanding of radians if they set the radius to one and unrolled it to be 2π.--Douggard (talk) 16:41, 11 June 2009 (UTC)


 * Agreed. Radius is more fundamental than diameter. (See for a rather lengthy discussion of this topic). However, I don't know much about editing animated GIFs, so the question is whether anyone who does have those skills agrees enough to make a version with radius 1 which unrolls to 2π. Kingdon (talk) 17:59, 17 April 2011 (UTC)


 * At least in the pi article, I would prefer keeping the diameter one, since &pi; is usually defined as the ratio of the circumference to the diameter. One could just as well define it using the radius instead, but at the cost of a slightly more complicated definition.  So I think it best to keep the image diameter-centric rather than radius-centric from the point of view of illustrating this definition.  That doesn't exclude the possibility of producing a different image with radius 1, but that would be illustrating something different and less relevant to the text of the &pi; article (for instance, in an article about radians, maybe such an image would be better).   Sławomir Biały  (talk) 01:47, 23 April 2011 (UTC)


 * Yeah, keeping the diameter-1 version around probably works better for pi. But a radius-1 variant could be used in Turn (geometry) and Radian. I'd probably also use the radius-1 one at Perimeter and Circumference. Kingdon (talk) 02:12, 23 April 2011 (UTC)


 * The new image is at File:2pi-unrolled.gif (thanks, illustration workshop and I've added it to Turn (geometry) and Radian. I'll probably do Perimeter and Circumference too although probably not for another day or more. Kingdon (talk) 02:04, 13 June 2011 (UTC)

Height of blue lines
I think this would be clearer if the height of the blue lines were 1. The first time I saw this animation cut from the diagram of the 4 circles showing the positioning of these vertical lines, to the wheel positioned to begin rolling, I thought "hey that one's bigger than the other four". Which was because the vertical blue lines don't have a height of 1. This is a problem of perception, not of inaccuracy of the (excellent) image. --Darxus (talk) 13:54, 20 August 2009 (UTC)

Optimization causes artifacts
The March 6th, 2010 optimization of the image reduced the file size. It looks identical to original, if displayed at original size. However, it also degraded the quality of the resized version of this image (the one used on the Pi page). This may be more of an issue with the GIF resizer having quality problems with 'optimized' GIF images. I am wondering if we should revert the image to the pre-March 6 version of the image. Mdrejhon (talk) 19:53, 14 March 2010 (UTC)