Talk:Koch snowflake
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So... what's the definition?
[edit]There's no formal definition for what the Koch snowflake *is*. I assume that, like most curves, it's defined as a subset of R². Where is the actual definition of that set? I see a definition of a sequence of curves K_1, K_2, K_3, ..., but saying, as the article does, that the Kock snowflake is "the limit" of this sequence doesn't mean anything. Limit in what sense? The set of points x such that any neighborhood of x intersects K_n for all sufficiently large n? Gaiacarra (talk) 23:42, 7 October 2016 (UTC)
- Yes, this article is severely flawed for not including a formal definition. Other discussion further down this talk page [[1]] may help, but it needs to be actually incorporated into the article. Jess_Riedel (talk) 03:04, 24 January 2021 (UTC)
3d koch snowflake
[edit]I notice that there's a mention of a 3d koch snowflake at the bottom of the page, but no link to get a picture. I found a picture here: http://graphics.ucsd.edu/~henrik/images/sflake.jpg but it isn't really a straightforward extension of the planar curve. I'd like to submit the construction on my website at: http://people.reed.edu/~goldena/solid-koch.html for consideration, if we want to have a 3d koch snowflake on this page. I hereby waive my copyright on the images at http://people.reed.edu/~goldena/solid-koch.html. They are in the public domain to be used by anyone for any purpose. 74.93.190.190 02:27, 14 March 2007 (UTC) goldena
This page was vandalised yesterday and i don't know how to change it back
See Wikipedia:How_to_revert_a_page_to_an_earlier_version. —Tobias Bergemann 09:13, 19 November 2005 (UTC)
Should we change references here to the "von Koch snowflake"? Dysprosia 00:12, 17 Nov 2003 (UTC)
I certainly wouldn't mind; however, I think (in general) the von is dropped when not using the first name. "von is German for "of"-- so its Helge of Koch..."of Koch" alone doesn't make as much sense. Lirath Q. Pynnor
- I thought it was common to put the "von" in? As it's part of the name? In any case, if leaving it out is the Right Thing to do, then leave it out :) Dysprosia 00:22, 17 Nov 2003 (UTC)
There isn't a "right thing" to do; if you change it, Im not going to revert it -- both are used. Lirath Q. Pynnor
I've always seen it called the "Koch curve", not "von Koch"--70.245.253.65 02:00, 20 May 2006 (UTC)
the koch snowflake is quite ridiculous as it can have infinite perimeter but finite area
- Congratulations. You just defined what a fractal is. --67.172.99.160 30 June 2005 21:01 (UTC)
- Please sign your posts. Why do you call the Koch snowflake "ridiculous" implying that it has somehow earned your contempt? Its perimeter is not a line but instead a narrow probability distribution that challenges our usual ideas of perimeter or circumference that apply so easily to ordinary 2-D shapes such as circles, ellipses, polygons.Cuddlyable3 13:51, 17 April 2007 (UTC)
Koch curve / Koch snowflake
[edit]I'd consider it odd that Koch snowflake redirects here when the article itself states:
- The better known Koch Snowflake (or Koch Star) is the same as the curve,[...]
How about a move to Koch snowflage (or Koch Star) and, if needed, a slight re-write of the article in order to make it suitable for the new location? Jobjörn 02:06, 25 February 2006 (UTC)
SEPARATE THE CURVE AND THE SNOWFLAKE!
- Yes. Please. ErkDemon (talk) 13:37, 12 August 2019 (UTC)
- They are not separable. The snowflake is just the subjective impression of 3 Koch curves. Cuddlyable3 18:45, 19 February 2007 (UTC)
- Of course they are separable. The Koch Curve is an open shape that doesn't look remotely like a snowflake and only has reflective symmetry, the "Koch Snowflake" or "Koch Island" is a closed shape with reflective and rotational symmetry, and ... due to it's sixfold symmetry (normal snowflakes have sixfold symmetry) ... looks like a snowflake. The Snowflake has area, the curve doesn't. To say that "Koch curve" means "Koch snowflake" is to corrupt the meanings of technical terms - what then happens if a researcher want to refer specifically to the actual curve and not to the snowflake? What happens if WP has told everyone that there's no such thing as a Koch Curve that isn't the snowflake?
- I think this is very, very bad. One might as well say that a cube is simply a shape assembled from squares, that WP's Square page should be deleted and redirect to Cube, and the Cube page should then explain that there's no difference between a square and a cube, and that a tetrahedron, which is related to a cube by being a variation on a different theme (Platonic solids), therefore also ought to be described as a variation on a square (facepalms). It's not just technically wrong ... its actually stupid. ErkDemon (talk) 13:37, 12 August 2019 (UTC)
I agree that the two are not separable, but the article is a bit confusing with alternating talk of curve/snowflake. Someone should clean it up a bit. By the way, Koch defined only the curve and every old math text I've read only references the curve. Other sites (like Wolfram) make the error of thinking Koch dreamed up the snowflake in 1904, but I've read the article and he didn't. Who first came up with the idea of putting 3 curves together to make a "snowflake" and when? --seberle (talk) 20:02, 23 January 2009 (UTC)
- Another excellent reason for separating the two subjects. If we want to explain that Koch invented the curve but not the snowflake, then this is kinda difficult if the page says that Koch Curve means Koch Snowflake. Also, consider the 3D extension of the Koch Curve that I uploaded - it's not a 3D extension of the Koch snowflake, and technically shouldn't be on the snowflake page! The same goes for the other shapes in the "Variants of the Koch curve" section - some of them are examples of open curves and not snowflake-like objects, and ought to be in a separate page. In fact, you could pretty much split the page into two at this point.
- There seems to be a very bad theme developing on WP fractals pages, where people decide to merge a range of different related subjects onto a single page. This is bad because it imposes a single way of sorting the data into groups, which prevents other potential groupings. The appropriate thing to do is to keep the individual entries separate, and for any "editorial overviews" for how they may be grouped to be done on separate category pages. If you put all these different variations onto the same page and delete the originals, it means that we can no longer include Koch Curve under "linear fractals" and Koch Snowflake under "fractals with area". We can no longer apply separate "date discovered" categories, we can't include some shapes under "fractal antennae" and not others, we can't sort by symmetry types, or rotational symmetry class.
- The way things are now, it's like not only saying "Hey, the subject of squares can't be separated from the subject of cubes, so we don't need a separate page on Square", but then going further and saying "... And the construction of a triangle is kindoffa variation on the way of making a square, so we'll delete the page on Triangle and make that a subsection of the Cube page, too." ErkDemon (talk) 13:40, 12 August 2019 (UTC)
What actually is the Koch curve?
[edit]I understand the sequence of curves but don't understand what is meant by saying the Koch curve is the "limit" of these curves. Is the Koch curve a subset of the plane? Is it the set of all points that are eventually always members of the curves in the sequence? Or something else? Is it a mathematical curve, a continuous function from [0,1] to the plane? If someone knows, it would be good if they could add that information to the article. Count Truthstein (talk) 18:16, 14 December 2008 (UTC)
- See Limit (mathematics). --92.37.88.76 (talk) 23:45, 20 December 2008 (UTC)
- Well, it basically means that the "triangles" converge to the Koch curve - they approach it. --92.37.88.76 (talk) 23:47, 20 December 2008 (UTC)
- I am fully aware of the definition of a limit. Each step in the sequence is a subset of the plane R^2 and I don't know of any standard way of defining a metric on P(R^2). Moreover if you did then we'd still have to say what the Koch curve is that it we claim it is tending to.
- I don't think it's very likely that it's done that way. Another way would be to view the steps in the sequence as functions from [0,1] to R^2, where there are sensible choices for metrics. However the limit could depend on the choices of the functions that represent the curves in the sequence. There are multiple ways of choosing these functions, because if f:[0,1]->R^2 is a path (injective continuous function), and g is a strictly increasing continuous bijection [0,1]->[0,1] then the image of (f.g) is the same as the image of f. Count Truthstein (talk) 02:53, 27 December 2008 (UTC) (edited 17:12, 27 December 2008 (UTC))
- Koch (1904) defined his function (after defining the curve) from the initial segment to the final curve by drawing a perpendicular from any point x on the initial segment and seeing where it first intersects any segment from any iteration. If that intersection is part of the final curve, fine; you're done. If not, draw a perpendicular from that second segment and see where it next intersects a segment from another iteration. And so on. Eventually you either hit the curve, or you have a convergent sequence of segments whose limit point is on the final curve. Either way, you have a mapping from x to a point f(x) on the Koch curve. --seberle (talk) 19:57, 23 January 2009 (UTC)
Countable / uncountable
[edit]Does the Koch curve have a countably infinite or an uncountably infinite number of sides? My gut says latter but I can't for the life of me figure it out formally. -pinkgothic (talk) 00:46, 1 April 2009 (UTC)
- Well, things that grow in an exponential manner tend to be uncountable; some version of diagonal method often works well enough to prove it. Here for instance, assume contrarily that you can order all the "sides" in a sequence {A_n}. You can now recursively construct a "side" that, for each i, is contained in a different side of an ith generation curve than A_i is. This freshly constructed one by definition doesn't appear anywhere in the sequence. Contradiction.
- The above is still not quite formal, because I am not sure what exactly do you mean by "sides" in this context. (Note that Koch Curve isn't differentiable anywhere!) But if you can formalise this notion somehow, the proof should work. 89.78.167.95 (talk) 09:11, 15 April 2009 (UTC)
- As said above, there are no "sides" in the Koch curve, which is the limit set of the Koch snowflake iterative process. Each generation in the Koch snowflake process introduces a number of new vertices which are points in the limit curve - the 0th generation introduces the three vertices of the original triangle; the 1st generation introduces the 9 points at the apex and base of each of the smaller triangles; the 2nd generation introduces 36 new points at the apex and base of 12 new triangles etc. The limit curve will contain a countable number of these "rational" points, as each one can be indexed by the generation at which it first appears, and then, say, counting clockwise around from the apex of the original triangle. But the limit curve also contains "irrational" points, which do not appear in any snowflake generation, but are the limit points of a sequence of "rational" points - a diagonal argument can be used to show that there are an uncountable number of these "irrational" points. A similar argument shows that there an uncountable number of points in the Cantor set, even though the end-points of the removed open intervals form a countable set. Gandalf61 (talk) 11:04, 15 April 2009 (UTC)
Convergence ?
[edit]Does the algorithm for construction eventually converge ? Is there a way to test whether a point is "on" the curve ? It seems that all the points keep changing, i.e. the points of the nth iteration curve seem to be potentially different from the (n+10)th iteration curve. I assume there must be convergence, otherwise it would make no sense to speak of "the curve", but a clarification (and ideally an understandable argument) would be good in the article ! —Preceding unsigned comment added by 84.74.106.187 (talk) 19:39, 21 August 2009 (UTC)
- As with other sets created through infinite iteration, the object is the ideal form of the set, the infinitieth iteration. While the lines between points are redefined in each iteration, vertices are not removed, only added, so if a vertex is a member of the set in one iteration, it will also be a member of the infinitieth iteration. Eventually, all the points between two vertices will be removed from the set, except the neighboring points an infinitesimal distance away in the direction of the vertices that it connected to within its own iteration. Of course, testing for set membership with the generating algorithm will not allow you to confirm that a point isn't in the set, only that it is or isn't in the nth iteration of the set, just as with the Mandelbrot set. And of course, you can't determine if an algorithm will run forever or not. If there's a standard algorithm that can give a straight "no" for membership of the Koch curve, I don't know about it. LokiClock (talk) 11:42, 17 February 2010 (UTC)
- Membership in the Koch fractal is decidable: Draw the fractal with line thickness . To ensure that the area covered by the line vanishes, choose . If a point is not in the set, it will be a finite distance away, and will cease to lie on the line after a finite number of iterations. Together with the vertex detection method you can decide for any given point whether it is part of the fractal. Paradoctor (talk) 17:37, 17 February 2010 (UTC)
- I'm having a little bit of trouble understanding the process as you're describing it. Do you have a link to somewhere where I can read about it in-depth? LokiClock (talk) 15:25, 18 February 2010 (UTC)
- Sorry, no link, pulled that one out of what I jokingly call my mind. I'll write something hopefully readable later. Paradoctor (talk) 16:54, 18 February 2010 (UTC)
- Here we go: Stated without proof: The Koch curve is compact. (IIRC, this is an exercise in some textbooks.) This means that every point that is the limit of a series of vertices is a part of the curve. This implies that all and only those points at a finite distance from all posible sequences of vertices are off the curve. Now start drawing the sequence of approximations, but decrease the line thickness by a constant factor for each iteration, 1/2 is enough. Since the line thickness becomes arbitrarily small, any point a finite distance away from the curve will cease to be covered by the line after finite number of iterations, and you'll know that the point is not on the curve.
- Now comes the part where I apologize: Writing this, I realized that the property of being on the curve appears to be undecidable. There should be some argument from Rice's theorem, but I'm brain-drained right now. HTH, Paradoctor (talk) 21:35, 18 February 2010 (UTC)
- Okay, are you saying to decrease the thickness of all the lines in each step, or only the new lines? If it's the former, I understand. And what is the difference exactly between a point being on the curve and a point being part of the fractal? LokiClock (talk) 13:54, 19 February 2010 (UTC)
- I meant all lines, but it shouldn't make much of a difference. Remember that non-vertex points of the segments will be removed in later iterations.
- We're talking about two different fractals. The curve has properties different from curve+interior. AFAIK, curve+interior is not compact, which makes a huge difference. Paradoctor (talk) 14:34, 19 February 2010 (UTC)
- I see. So the compactness in this case determines the decidability? LokiClock (talk) 14:48, 19 February 2010 (UTC)
- Okay, are you saying to decrease the thickness of all the lines in each step, or only the new lines? If it's the former, I understand. And what is the difference exactly between a point being on the curve and a point being part of the fractal? LokiClock (talk) 13:54, 19 February 2010 (UTC)
- There may be a way of proving computability of non-membership without relying on compactness, but that question is beyon my ken. Paradoctor (talk) 15:13, 19 February 2010 (UTC)
Sphereflake
[edit]Besides the shape's idiosyncrasy (being sphere-packing-based), the bit about it is unsourced, claims a specific developer, and until I changed it put its name in bold. Is there any support for its notability or the particular choice of this article for its place of inclusion? LokiClock (talk) 14:46, 16 February 2010 (UTC)
- According to [2]: "Exercise 74: Sphereflake" (p545&566) in Roland E. Larson; Robert P. Hostetler; Bruce H. Edwards (1998). Calculus. Houghton Mifflin. ISBN 9780395869741. Retrieved 16 February 2010., I'll add more later. Paradoctor (talk) 15:08, 16 February 2010 (UTC)
Countable / Uncountable length
[edit]A couple of editors question whether the length is well defined. Surely it is as well defined as any limit of a divergent sequence? Some sources say the snowflake's perimeter has infinite length (e.g. the article's first external link: [3]). So is it countable or uncountable? The article should say one way or another. --Michael C. Price talk 20:22, 20 March 2010 (UTC)
- The source listed by you does not look like an RS to me. The statement looks fishy to me, as per my edit summary. Note that some sets are not measurable. Also, it is not hard to construct a fractal set whose limit is the unit interval. Thich gives us a series of curves whose length goes to infinity, while its limit has a clearly defined finite length. If you can cite a couple of good sources talking about "infinite length", please add them. IMPO, this notion looks like a common misconception. Of course, I'm not a reliable source. ;) Paradoctor (talk) 21:01, 20 March 2010 (UTC)
- I'm puzzled by the link you provided. What's its relevance? The link I posted was from the article; if it isn't reliable (and here's a better source, BTW, that states the Koch curve has infinite length) then what was it doing in the article? If the Koch perimeter is not measurable then I presume the Menger sponge also doesn't have an infinite area, yet it is desribed: The Menger sponge simultaneously exhibits an infinite surface area and encloses zero volume. .--Michael C. Price talk 06:47, 21 March 2010 (UTC)
- The link is the author's homepage. Doesn't really look like an authority to me. ;) His copyright notice is here.
- "what was it doing in the article": Obviously, someone misjudged it's RSness.
- Menger sponge: The statement is cited to an RS, that's what makes the difference. Also note that these are different fractals, I did not say that all fractals are unmeasurable. Please note that the limit of a sequence may have properties not shared with any members of the sequence. A simple example is the series . None of its members is an integer, yet the limit is. If you don't find that remarkable, check out 1 − 2 + 3 − 4 + ···, which can have a sum of , depending on the summation method.
- "better source": I'm afraid not. Skinner's page is part of a student project, and the teacher of the course stated "There were also a few real duds among these. You can decide for yourself which were which.", so we still have nothing solid to go on. Paradoctor (talk) 09:52, 21 March 2010 (UTC)
- The concepts of countable and uncountable only apply to infinite sets. A line is a set of points (and even a line with finite length is an uncountable set of points) but the length of a line is not a set - it is an example of a measure. So it does not make sense to describe the length of a line as being countable or uncountable. The phrase "The Koch curve has an infinite length" is shorthand for saying that the lengths of the iterations that approach the Koch curve do not approach a finite limit. Gandalf61 (talk) 13:06, 21 March 2010 (UTC)
- How many inches in an endless straight line (in Euclidean space)? --Michael C. Price talk 21:05, 21 March 2010 (UTC)
- "as well defined as any limit of a divergent sequence": That one slipped past me. Divergent sequences have no limit, that is precisely what distinguishes them from convergent sequences. You might define a measure which permits infinite values, and then you can say that the sequence of lengths of the Koch curve approximations converges onto the limit value "infinite". But this is a property of the sequence, not necessarily of its limit. The problem is that you need to show that your definition of the measure "length" is applicable to the Koch curve. The Banach-Tarski paradox shows that you may not simply assume that all sets are measurable. That's why I'm asking for a reliable source. Paradoctor (talk) 15:09, 21 March 2010 (UTC)
- From gscholar:
- It follows that the Koch curve has infinite length
- length of the Koch curve becomes infinite
- the length of the limit curve is infinite Full PDF
- extrapolates to give infinite length for the fractal curve
- its border, a scaling fractal of infinite length
- the actual length of a fractal curve between two points a finite distance apart is infinite
- The Koch curve is self-similar at every scale and has, in the limit ... infinite length
- Koch Snowflake(s) ... are of infinite length.
- Any reliable? --Michael C. Price talk 21:28, 21 March 2010 (UTC)
- Let me first compliment you for looking for sources rather than complaining, I get the latter far too often. ;)
- The author is a professor of mathematics. Problem is, this is just a coursenote, nothing peer-reviewed, which is what we're looking for.
- This author is an MD, this one is at least professor of biomathematics. It is not clear, though, that he vetted this particular statement. Also note that this is a physiology journal, not mathematics.
- Mandelbrot in Science would clearly be an authoritative source. I need to see sufficient context to make sure that he didn't make this statement merely to knock it down. Do that, and we're done here. :) Don't get your hopse too high, though: "Geographical curves are so involved in their detail that their lengths are often infinite or, rather, undefinable."
- The author has published some work in poweder physics. He did work on using fractals to describe the behavior of powders, but that doesn't make him an WP:RS for us, especially seeing as this work is now ~30 years old.
- Good old Gardner. Not an RS, though I, like many, like his stuff.
- Another physicist. International Journal of Fracture? ^_^
- Chemical Engineering or geology, take your pick.
- Lawyers? What has become of WP:LEGALTHREAT? ;)
- Let me sum it up. We need either a journal article or a major textbook in mathematics competent on fractals and measures. So far, your best bets are the Mandelbrot article or finding a peer-reviewed paper by the first professor. Happy editing, Paradoctor (talk) 22:57, 21 March 2010 (UTC)
- Full Mandelbrot PDF. The context is fine - he does not knock it down. --Michael C. Price talk 04:51, 22 March 2010 (UTC)
- Let me first compliment you for looking for sources rather than complaining, I get the latter far too often. ;)
- From gscholar:
- If you include the quote "Thus, the length of the limit curve is infinite, even though it is a “line.”" from page 637, you have found yourself a valid citation to an WP:RS. :) Don't use the link to the full PDF, though, it's a copyvio as it violates JSTOR's terms of use.
- As Gandalf61 explained, it doesn't make sense to quantify the infiniteness of length as countable or uncountable, hence my edit. However, I agree with Michael that the curve has infinite length, not just that the lengths of the stages in the construction converges to infinity. Another source for this statement is The Princeton Companion to Mathematics, where it is explicitly stated (p. 184) that the Koch snowflake has infinite length. /Pontus (talk) 07:35, 22 March 2010 (UTC)
- See my response to Gandalf61 for why I do not, yet ay least, accept his statement. Is the length of an infinite straight line itself infinite? Yes, if we measure with respect any unit of measurement. Now form a list of the unit lengths, and every part appears somewhere in the ordered list - therefore the length of a straight line is countable. For a Koch curve such a list is not constructible, therefore its length is uncountable? --Michael C. Price talk 11:07, 22 March 2010 (UTC)
- Perhaps you mean that the 1-dimensional Hausdorff measure on the curve is not σ-finite? /Pontus (talk) 11:44, 22 March 2010 (UTC)
- See my response to Gandalf61 for why I do not, yet ay least, accept his statement. Is the length of an infinite straight line itself infinite? Yes, if we measure with respect any unit of measurement. Now form a list of the unit lengths, and every part appears somewhere in the ordered list - therefore the length of a straight line is countable. For a Koch curve such a list is not constructible, therefore its length is uncountable? --Michael C. Price talk 11:07, 22 March 2010 (UTC)
- Neither a textbook, nor a peer-reviewed publication, even though written by experts. Please note that, IMHO, even the Mandelbrot paper is plain wrong. But it is an RS, and for our purposes far superior to the PCM, so the onus is on me to prove anything to the contrary. Cf. the first hit, which is an article in Chaos, Solitons & Fractals. Paradoctor (talk) 08:19, 22 March 2010 (UTC)
- I would have thought that the PCM is a more reliable source than Mandelbrot. However, since they agree, it is not a problem.--Michael C. Price talk 11:07, 22 March 2010 (UTC)
Mathematics and the imagination
[edit]The Koch snowflake features prominently in chapter 9 of Mathematics and the Imagination. The chapter (pages 299 to 356) is called "Change and Changeability — The Calculus". The figures (#145 to #150) range over pages 345 to 350 showing the first six stages of the construction. On page 345 the authors say "Its pathological character is born out by this incredible feature ... the length of its perimeter is infinite." On page 347 they say, "...it is not possible to tell at any point on the limit curve the direction in which it is going, that is, the tangent line does not exist."
Instead of mounting the triangles on the outside, they may be taken from the interior of the preceding figure. The result is called the "Anti-Snowflake". The first four stages of the process is illustrated with figures #151 to #162 on page 351.
A space-filling curve is then introduced (pages 352,3) with figures #159 to #162.Rgdboer (talk) 19:58, 18 April 2011 (UTC)
Proof of area incomplete
[edit]Is it just me or is the proof of the area of the Koch snowflake missing the most interesting part: why do the little triangles never overlap? (In the similar problem http://www.artofproblemsolving.com/Forum/viewtopic.php?f=41&t=5333 , they do overlap, so that the naive method of calculating the area fails.) -- Darij (talk) 22:28, 29 March 2012 (UTC)
- You are right, the prof is not complete. Prokofiev2 (talk) 08:21, 30 March 2012 (UTC)
My proof may be too long but still worth considering
[edit]I expanded the proof of the area and perimeter of the snowflake but it was undone. I think that the explanation as it was is too short and doesn't really get you from point A to point B in the proof smoothly enough. What do the others think?
Here's my edit: http://en.wiki.x.io/w/index.php?title=Koch_snowflake&oldid=537408182
Mtanti (talk) 11:11, 10 February 2013 (UTC)
Who is it named after?
[edit]I think that discussing origin and creation circumstances would be appropriate for an article like this. At least a brief mention.174.56.55.37 (talk) 17:54, 23 July 2014 (UTC)
Nazi sign?
[edit]![](http://up.wiki.x.io/wikipedia/commons/thumb/2/28/Karperienflake.gif/150px-Karperienflake.gif)
I wonder how long will it take until the US Congress recognise this sign as Neo-Nazi sign? Since they already called the Idea of Nation sign as one (see Azov Battalion). Aleksandr Grigoryev (talk) 22:57, 3 January 2017 (UTC)
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Why do we need 'Not to be confused with Dave Rubin'?
[edit]The Dave Rubin page doesn't contain any reference to Koch snowflakes and the name is not at all alike. The reference was added by 86.44.63.103 yesterday. Albert Pool (talk) 10:24, 30 November 2018 (UTC)
- It is just vandalism. I have already reverted it. --Zupanto (talk) 19:01, 5 December 2018 (UTC)
- The joke is that, since Dave Rubin is conservative/classical liberal/libertarian, "Koch" can be reinterpreted as the conservative/classical liberal/libertarian Koch Brothers and "snowflake" as the insult "snowflake". The reason why there are (presumably) three vandals with completely different IP addresses is that this page has been posted on the leftist sub-Reddit r/ChapoTrapHouse (named after the podcast) (at least) four times ([4] (the original vandal probably comes from here), [5], [6], [7] (the (presumably) two reverters probably come from here)). --Zupanto (talk) 22:51, 5 December 2018 (UTC)
Semi-protected edit request on 24 January 2019
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I would like to remove the completely irrelevant reference to Dave Rubin at the top of the page. DiabolikDownUnder (talk) 09:57, 24 January 2019 (UTC)
Done – Jonesey95 (talk) 11:18, 24 January 2019 (UTC)
File:KochTurtleAnim.gif
[edit]@David Eppstein: The image File:KochTurtleAnim.gif (code: [[File:KochTurtleAnim.gif|thumb|Animation]]) was removed from this article because its inclusion doesn't seem to add, "any understanding or useful information about this topic". However, some readers, especially highly visual learners, may get a deeper understanding through a small illustration or short animation than through a text description however lengthy. I think math content on Wikipedia should be accessible to all people and I assume that the creator of the animation thought that it would add either "understanding," or, "useful information," if not both. Hyacinth (talk) 03:42, 14 September 2019 (UTC)
Minkowski fractal
[edit]See the discussion at Wikipedia talk:WikiProject Mathematics#Minkowski fractal. Hyacinth (talk) 03:53, 14 September 2019 (UTC)
Image: SVG vs PNG
[edit]Which is preferable: File:Koch quadratic island L7 3.png or File:Koch quadratic island L7 3.svg? Hyacinth (talk) 02:13, 3 April 2020 (UTC)
- For display within the article it makes no difference, but if we expect some viewers to click on the article image and look more carefully at it blown up then the svg is better (not least because when I try it in my browser I see the png displayed as a black shape with a transparent background displayed over black, so basically invisible). —David Eppstein (talk) 05:26, 3 April 2020 (UTC)
Area formula
[edit]The area formula could be made much simpler ... With original triangle of area a0, with 3 sides, we get additional area of 3*1/9*a0, and four times as many sides, so the next addition to the area is 3/9*4/9, and so on, to give a0 + a0*1/3*(4/9)^n-1. The second half of this expression is the formula for the nth term in a G.P. with 'a'= 1/3 and 'r'= 4/9. This has a sum given by the usual formula: 1/3 divided by (1 - 4/9), which straight away gives 3/5. Add in the original area and you have 8/5. Jerryfrog (talk) 04:50, 8 November 2023 (UTC)
Number of sides formula incorrect?
[edit]The articles says number of sides after n iterations is given by ...
But on iteration 0 (the initial triangle) there are 3 sides, but the formula with n = 0 would give 3/4 of a side. Axlesoft (talk) 12:10, 21 February 2024 (UTC)
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