Portal talk:Mathematics/Archive2013

{{talkarchive}}

"Show new selections" + "Did you know"

Does anyone know why the "Did you know" logic uses only the current day-of-the-week and the current week-of-the-year? This means that clicking the "Show new selections" button doesn't reveal any new DYKs; to see new ones you have to wait until tomorrow. How about using {{CURRENTTIMESTAMP}} instead? -- John of Reading (talk) 22:01, 27 March 2013 (UTC)

:It's been like that since before I started editing the portal. {{CURRENTTIMESTAMP}} sounds like a good idea to me ―JuPitEer (talk) 10:14, 30 March 2013 (UTC)

::I rather like the scheme used at Portal:Archaeology/Did you know, which randomly picks one of the first 5, one from the second 5, and so on. So the reader sees a very different mix of facts each time. -- John of Reading (talk) 10:22, 30 March 2013 (UTC)

Self-affinity

Can someone competent provide some pictures for this article?Lbertolotti (talk) 00:22, 3 July 2013 (UTC)

:Which article do you need a picture for? --JustBerry (talk) 04:15, 4 July 2013 (UTC)

http://en.wikipedia.org/wiki/Self-affinity

General Questions

1. Is there an official WikiProjects Mathematics userbox for user pages?

2. How does one "maintain" the Wikipedia Mathematics Portal? --JustBerry (talk) 04:17, 4 July 2013 (UTC)

: I don't know if it's official but there's a userbox on my user page which I got from somewhere: feel free to copy it. As for your second question: the same as any other page is maintained. If you see a problem or think it can be improved go ahead and edit it, or one of the subpages.--JohnBlackburnewordsdeeds 05:36, 4 July 2013 (UTC)

Selected picture

Given that my suggestion to maintain a "queue" of upcoming featured pictures has not prevented "redlinks" from showing up under "Picture of the Month" on the portal page (as can be seen there as I type this), I now suggest converting that feature to a "Selected picture" format (either by week number, or by being randomly chosen). I see that the "Selected article" feature used to be chronologically based, but was converted to a random portal component back in 2007. We should probably do the same with the pictures. Provided no one objects, I'll do this myself at some point... unless someone else beats me to it. - dcljr (talk) 22:59, 2 September 2012 (UTC)

: Sounds like a good idea. I've done a few in the past but neither I nor anyone else seems able to keep on doing it. And there are several years of PotM so many will be ones that readers haven't seen before, unless they've browsed the PotM archives.--JohnBlackburnewordsdeeds 01:16, 3 September 2012 (UTC)

:: Since it seems like we'll have to move or copy the existing "featured picture" subpages to different titles to be able to use the "random" approach, maybe we should first discuss whether any of the images that have been used in the past should not be used again (maybe a better version exists, or the corresponding topic has too many images for it, etc.). Here's a table summarizing the featured images up to this point (76 by my count, including one image [from May 2006] that was never added to the "official" archive). Obviously, if you want to look through the images themselves and their corresponding text, go to Portal:Mathematics/Featured picture archive instead. I put this here mainly for what can be gleaned by sorting the columns (e.g., how many times certain topics have appeared, how many times different file types have appeared). I'll add my comments/suggestions a little bit later (maybe tomorrow?). In the meantime, if any corrections or additions are necessary, feel free to edit the table... - dcljr (talk) 05:49, 4 September 2012 (UTC)

:: Note: The table is initially sorted in reverse chronological order by month pics were most recently featured; re-sort the column to get it by month they were first featured. - dcljr (talk) 23:59, 11 September 2012 (UTC)

class="sortable collapsible collapsed wikitable"

! File !! Format !! Animated? !! Month(s) !! Article !! Credit !! Notes

:File:Hexaflexagon-construction-and-use.jpgJPEGstatic2012-10FlexagonOKexpand description
:File:Torus cycles.pngPNGstatic2012-09TorusOK (minor bot modification)merge torus description with 2006-05; expand description to explain "homology cycles"; see also 2009-08 and 2011-11; image has been rotated 270° by a bot from its original orientation
:File:Economics_Gini_coefficient2.svgSVGstatic2012-08Lorenz curvelook into (minor modification by other user, but major modification by credited user)
:File:Tetrahedral_group_2.svgSVGstatic2012-07Symmetry groupOK (trivial modification by other user)
:File:Adobe_Flex_BubbleChart.pngPNGstatic2012-06Bubble chartprobably [//uk.wikipedia.org/wiki/%D0%A1%D0%BF%D0%B5%D1%86%D1%96%D0%B0%D0%BB%D1%8C%D0%BD%D0%B0:%D0%92%D0%BD%D0%B5%D1%81%D0%BE%D0%BA/%D0%9C%D0%B0%D0%BA%D1%81_%D0%A0%D0%BE%D0%B7%D0%B4%D0%BE%D0%B1%D1%83%D0%B4%D1%8C%D0%BA%D0%BE Макс Роздобудько]
:File:Knight's_tour_anim_2.gifGIFanimated2012-05Knight's tourOK
:File:Jahnke_gamma_function.pngPNGstatic2012-04Gamma functionlook into (uploaded by credited user, but originally uploaded to Citizendium by a user there))
:File:Hairy_ball.pngPNGstatic2012-03Hairy ball theoremOK (although credited user doesn't seem to exist)
:File:Trunc-icosa.jpgJPEGstatic2012-02Truncated icosahedronOK
:File:HypotrochoidOutThreeFifths.gifGIFanimated2012-01HypotrochoidOK (minor modifications by other users)
:File:LogisticMap_BifurcationDiagram.pngPNGstatic2011-12Bifurcation diagramOK
:File:Mug_and_Torus_morph.gifGIFanimated2007-05, 2011-11HomeomorphismOKmerge the two descriptions; see also 2009-08 and 2012-09
:File:Pythag_anim.gifGIFanimated2011-10Pythagorean theoremOK? (modified by another user, but minor?)2010-09 static image illustrates essentially the same geometrical proof
:File:Konigsberg_bridges.pngPNGstatic2011-09Seven Bridges of KönigsbergOKexpand description a bit (add mathematical significance)
:File:Circle-trig6.svgSVGstatic2011-08Trigonometrylook into (modified by other users, but minor or major?)also used in a selected article; expand description a bit
:File:Petersen1_tiny.svgSVGstatic2011-07Petersen graphOK (minor modification by other user)be more specific in description?
:File:Evolution5glyph.pngPNGstatic2011-065 (number)wrong (uploader credited instead of original creator)expand description a bit (intermediate writing systems? approximate dates?)
:File:Pi-unrolled-720.gifGIFanimated2009-04, 2011-05PiOKmerge the two descriptions (if necessary)
:File:Paradoxical_decomposition_F2.svgSVGstatic2011-04Banach–Tarski paradoxOK (SVG conversion by later user)see also very different image (2008-09) for same topic; merge descriptions?
:File:Knot_table.svgSVGstatic2011-03Knot theoryOK
:File:QuaternionJuliaWP.pngPNGstatic2008-01, 2011-02Julia setOKsame description for both
:File:Steiner_chain_animation_ellipse.gifGIFanimated2011-01Steiner chainOK
:File:Desargues_theorem_alt.svgSVGstatic2010-12Desargues' theoremmerge this and 2008-07 description; choose one of the images
:File:Hadwiger-Nelson.svgSVGstatic2010-11Hadwiger–Nelson problem
:File:Tricoloring.pngPNGstatic2010-10Trefoil knot
:File:Pythagorean_proof.svgSVGstatic2010-09Pythagorean theoremessentially the same geometrical proof as 2011-10, but different arrangement of regions in final picture and not animated
:File:Order-3_heptakis_heptagonal_tiling.pngPNGstatic2010-08Uniform tilings in hyperbolic planerewrite description to explain "(p q r)" notation and mention connection to artist M. C. Escher; 2009-05 and 2006-10 are a different kind of tiling
:File:Mandelbulb078a.JPGJPEGstatic2010-062010-07Mandelbulbexpand description to explain "power 9"
:File:P._Oxy._I_29.jpgJPEGstatic2010-042010-05Euclid's Elementsmerge first and second sentences in description?
:File:Missing_Square_Animation.gifGIFanimated2010-03Missing square puzzleslight rewrite to say "area of gap"
:File:Menger-Schwamm.pngPNGstatic2010-02Menger spongeclarify self-similarity aspect (i.e., whole to red portion); see also similar 2008-06 (Sierpiński pyramid)
:File:Ortho_solid_011-uniform_polychoron_53p-t0.pngPNGstatic2010-01Great grand 120-cellcan we include some statement about the "significance" or "meaning" of the figure?
:File:Bezier_4_big.gifGIFanimated2009-112009-12Bézier curve
:File:GalaxyOfGalaxies.jpgJPEGstatic2009-10Mandelbrot setone of 5 pics of the Mandelbrot set, along with 2007-07, 2007-06, 2005-07, and 2005-01 — do we really need all of them?
:File:Villarceau_circles.gifGIFanimated2009-082009-09Villarceau circlessee also 2011-11 and 2012-09
:File:Conways_game_of_life_breeder_animation.gifGIFanimated (large)2009-07Conway's Game of Life
:File:Fractal_Broccoli.jpgJPEGstatic2009-06Fractaldescription needs light copy editing
:File:Penrose_Tiling_(Rhombi).svgSVGstatic2009-05Penrose tilingmerge this description with 2006-10 and pick one (this one); 2010-08 is a different kind of tiling
:File:Sieve_of_Eratosthenes_animation.gifGIFanimated (large)2009-03Sieve of Eratosthenesexpand description a bit
:File:SterlingFractal-GeneratedImage.jpgJPEGstatic2009-02Fractalexpand description to emphasize use of fractals in art
:File:Euclidian_and_non_euclidian_geometry.pngPNGstatic2009-01Parallel postulateperhaps condense original description a bit so that more historical context can be added?
:File:Fractal_tree_(Plate_b_-_2).jpgJPEGstatic2008-12Pythagoras treehow "squares" and "triangles" relate to the image needs some clarifying, I think
:File:Lorentz.PNGPNGstatic2008-11Lorenz attractorI think there may be better Lorentz attractor images now; maybe merge this and 2006-02 description
:File:PascalTriangleAnimated2.gifGIFanimated2008-10Pascal's triangleadd some applications to description?
:File:Banach-Tarski_Paradox.svgSVGstatic2008-09Banach–Tarski paradoxalso used in a selected article; see also the very different image (2011-04) for same topic; while this image clearly illustrates the paradox, is it really one of our finest images?
:File:Exponential_Function_(Real_Part).pngPNGstatic2008-08Exponential functionneed to rewrite description since image only shows real part
:File:Teorema_de_desargues.svgSVGstatic2008-07Desargues' theoremmerge this and 2010-12 description; choose one of the images
:File:Sierpinski_pyramid.jpgJPEGstatic2008-06Sierpiński trianglesee also similar 2010-02 (Menger sponge)
:File:Zeta_polar.svgSVGstatic2008-05Riemann zeta function
:File:IQ_curve.svgSVGstatic2008-04Normal distributionI'm not sure I like this image; there are many more interesting/informative illustrations of the normal distribution out there...
:File:Triangles_(spherical_geometry).jpgJPEGstatic2008-03Spherical geometrymaybe expand description a bit to reference specific triangles in image
:File:Moebiusband wikipedia animation.ogvOGGanimated (video)2008-02Möbius stripmaybe expand description a bit, including applications
:File:Borromean.jpgJPEGstatic2007-12Borromean ringsexpand description a bit
:File:Joconde.gifGIFstatic2007-11Golden ratiounfortunately, according to the Golden ratio article, the suggestion in the description is "not supported by anything in Leonardo's own writings"; see also 2006-09 (golden rectangle)
:File:Atractor_Poisson_Saturne.jpgJPEGstatic2007-10Attractoris it possible to explain this particular attractor?
:File:End_of_universe.jpgJPEGstatic2007-09Trianglethis image doesn't appear to be rendered accurately: the base of the triangle on the sphere, for example, wouldn't be (parallel to) a line of latitude, as shown in the figure, but instead would lie on a great circle of the sphere, which would make it appear to "bow outward" toward the "south pole"; the triangle on the hyperbolic surface doesn't look right either: the sides need to "bow inward" more; someone should create an accurate rendering of this; also, not sure Triangle is the best target article for this image
:File:Bisection_construction.gifGIFanimated2007-08Compass and straightedge constructionsprobably should expand description a bit to suggest the significance of straightedge-and-compass constructions in the history of mathematics; 2006-09 is also a compass-and-straightedge construction
:File:Mandel_zoom_07_satellite.jpgJPEGstatic2007-07Mandelbrot setone of 5 pics of the Mandelbrot set, along with 2009-10, 2007-06, 2005-07, and 2005-01 — do we really need all of them?
:File:Mandelbrot_Animation1.gifGIFanimated2007-06Mandelbrot setone of 5 pics of the Mandelbrot set, along with 2009-10, 2007-07, 2005-07, and 2005-01 — do we really need all of them?
:File:CollatzFractal.pngPNGstatic2007-04Collatz conjecturealso used in a selected article; expand description to explain a little about the conjecture and what the image has to do with it
:File:Tesseract.gifGIFanimated2007-03Tesseractmerge description with 2006-06 and pick one of the images?
:File:Icosahedron-wireframe.jpgJPEGstatic2007-02Icosahedronperhaps mention some applications and/or appearances in nature
:File:MorinSurfaceFromTheTop.PNGPNGstatic2007-01Morin surfacedoes this have any applications? and are there any images showing what the surface looks like in the process of turning into the Morin surface ("step 2" in the description of the eversion in the article)?
:File:Circle_map_poincare_recurrence.jpegJPEGstatic2006-12Circle mapperhaps try to explain what a circle map is, if possible, and include at least one application mentioned in the article; note that Circle map currently redirects to Arnold tongue
:File:KleinBottle-01.pngPNGstatic2006-11Klein bottleexpand description to explain more about what a Klein bottle is, its connection to the more familiar Mobius strip (see 2008-02), and the differences between the 4-D surface and its 3-D "real-world" equivalent
:File:Pen0305c.gifGIFstatic2006-10Penrose tilingmerge this description with 2009-05 and pick one (the other one); 2010-08 is a different kind of tiling
:File:Construction_of_Golden_rectangle.svgSVGstatic2006-09Golden rectangleprobably should explain how the construction is accomplished; include some discussion of significance of golden rectangle/ratio in mathematics and art; 2007-08 is also a compass-and-straightedge construction; see also 2007-11 (golden ratio)
:File:Dodecahedron.jpgJPEGstatic2006-08Dodecahedronalso used in two selected articles; maybe expand description a bit; see also 2005-12
:File:Hypercube.svgSVGstatic2006-06–2006-07Tesseractmerge description with 2007-03 and pick one of the images?
:File:Torus.jpgJPEGstatic2006-05[//en.wikipedia.org/w/index.php?title=Portal:Mathematics/Featured_picture&diff=50004105&oldid=47510211][//en.wikipedia.org/w/index.php?title=Portal:Mathematics/Featured_picture&diff=next&oldid=53674275] (not in archive)Torusmerge torus description with 2012-09 and expand a bit; see also 2009-08 and 2011-11
:File:ConnectedDynkinDiagrams.pngPNGstatic2006-04Dynkin diagramcan we explain this a bit more?
:File:Lorenz_system_r28_s10_b2-6666.pngPNGstatic2006-02–2006-03Lorenz attractormaybe use an SVG version instead? this image is more "iconic", I think, than the similar 2008-11 image
:File:NautilusCutawayLogarithmicSpiral.jpgJPEGstatic2006-01Logarithmic spiralexpand description to explain what characterizes a logarithmic spiral and mention some other examples
:File:Cuboctahedron.jpgJPEGstatic2005-12Cuboctahedronsee also 2006-08
:File:Mandelpart3.jpgJPEGstatic2005-07–2005-11Mandelbrot setone of 5 pics of the Mandelbrot set, along with 2009-10, 2007-07, 2007-06, and 2005-01 — do we really need all of them?
:File:Conic_sections_3.pngPNGstatic2005-03–2005-06Conic sectionexpand and copy edit description a bit; mention some history and/or applications
:File:Buddhabrot-deep.jpgJPEGstatic2005-02Buddhabrotexpand description to explain briefly the difference between the usual rendering of the Mandelbrot set and this one
:File:Mandelpart2.jpgJPEGstatic2005-01Mandelbrot setone of 5 pics of the Mandelbrot set, along with 2009-10, 2007-07, 2007-06, and 2005-07 — do we really need all of them?

Some general comments: Too many fractal pics. Only need one Mandelbrot pic (maybe a mosaic showing a "zoom sequence", as shown in the article?). Other duplicate topics should only have one pic for each. The GIFs for Conway's Life (2009-07) and the Sieve of Eratosthenes (2009-03) don't animate when resized. - dcljr (talk) 23:59, 11 September 2012 (UTC)

: I wouldn't say there are too many fractal pics. The reason there are so many is because editors have chosen them in the past, and those are the pictures they've found to be most attractive. In maths we are even more limited because the vast majority of maths articles, even good and featured ones, are not good sources of images. Even those that in theory could supply good pictures often lack them as they can't just be photographs or reproductions but need creating by hand with dedicated tools. We end up with the images that editors choose to make and make well, which are disproportionately fractals. More can be seen here Wikipedia:Featured_pictures/Sciences/Mathematics, one of which is today's featured picture.--JohnBlackburnewordsdeeds 00:20, 13 September 2012 (UTC)

:: I agree that fractals are pretty pictures that are easy to make, but having almost 15% of the images (11 of 76) being related directly to fractals overemphasizes that small area of mathematics, IMHO. I hope you would agree that we don't need five different images just for the Mandelbrot set...? - dcljr (talk) 04:02, 13 September 2012 (UTC) [Actually, one could say there are up to 14 fractal related images, if you want to be more "liberal" in your counting. - dcljr (talk) 20:31, 13 September 2012 (UTC)]

::: BTW, in case there's any misunderstanding, I'm not saying above that we should have 1 Mandelbrot pic as the only fractal pic... - dcljr (talk) 22:57, 18 September 2012 (UTC)

: Oh, and another general comment: we need to go through the "credits" and make sure each one credits the actual creator of the image and/or the uploader (when relevant — see 2012-04, for example), not the user who chose the image. Also, some of the images might have had new versions uploaded over the originals, and a different user might need to be credited because of this. (I don't know if any of the credits are actually wrong, but it's a good idea to check.) - dcljr (talk) 19:11, 2 October 2012 (UTC)

:: Ugh. Getting the credits "right" is turning out to be harder than I initially thought. I figured it would be easy to tell whom should get the credit for any given image, although it's not necessarily the last uploader. If someone makes a minor change to an image, it should still be credited to the original creator. But if someone makes a "significant" change to an image, then it seems like it should be credited to the latter user. But at what point does a modification become "significant" enough to warrant changing the credit? It's annoying.... - dcljr (talk) 22:50, 15 October 2012 (UTC)

: I've made it show a random previous month's picture instead of a red link if there is no picture yet for a month ―JuPitEer (talk) 15:58, 2 November 2012 (UTC)

::: OK, after a year of inactivity, I'm going to start creating the infrastructure for a random "Selected picture" component based on the standard {{tl|Random portal component}} template (not sure why we needed a "custom version" -- maybe I'll find out as I'm doing this). As with the switch from "Featured article" to "Selected article", I'm leaving the current "Featured picture" infrastructure the way it is. Not sure how long this will take before it's ready to go live... - dcljr (talk) 20:17, 7 November 2013 (UTC)

In other Wikimedia projects

I've been bold and added another component to this portal page, "In other Wikimedia projects". I hope no one's deeply offended by this. I've also [//en.wikipedia.org/w/index.php?title=Portal:Mathematics&diff=583453539&oldid=583451245 simplified the formatting] a bit. Not sure why "Topics in mathematics" was floated right when it takes the full page width, anyway. The 'div' element wasn't closed, so I removed it. If this broke anything for anyone, just restore the 'div' tag. - dcljr (talk) 23:07, 26 November 2013 (UTC)