Misplaced Pages

talk:WikiProject Mathematics - Misplaced Pages

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.

This is an old revision of this page, as edited by Incnis Mrsi (talk | contribs) at 17:24, 27 August 2019 (Draft:Genus of a group: whoops). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Revision as of 17:24, 27 August 2019 by Incnis Mrsi (talk | contribs) (Draft:Genus of a group: whoops)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff)
This is a discussion page for
WikiProject Mathematics
This page is devoted to discussions of issues relating to mathematics articles on Misplaced Pages. Related discussion pages include:
Please add new topics at the bottom of the page and sign your posts.
? view · edit Frequently asked questions

To view an explanation to the answer, click on the link to the right of the question.

Are Misplaced Pages's mathematics articles targeted at professional mathematicians? No, we target our articles at an appropriate audience. Usually this is an interested layman. However, this is not always possible. Some advanced topics require substantial mathematical background to understand. This is no different from other specialized fields such as law and medical science. If you believe that an article is too advanced, please leave a detailed comment on the article's talk page. If you understand the article and believe you can make it simpler, you are also welcome to improve it, in the framework of the BOLD, revert, discuss cycle. Why is it so difficult to learn mathematics from Misplaced Pages articles? Misplaced Pages is an encyclopedia, not a textbook. Misplaced Pages articles are not supposed to be pedagogic treatments of their topics. Readers who are interested in learning a subject should consult a textbook listed in the article's references. If the article does not have references, ask for some on the article's talk page or at Misplaced Pages:Reference desk/Mathematics. Misplaced Pages's sister projects Wikibooks which hosts textbooks, and Wikiversity which hosts collaborative learning projects, may be additional resources to consider.
See also: Using Misplaced Pages for mathematics self-study Why are Misplaced Pages mathematics articles so abstract? Abstraction is a fundamental part of mathematics. Even the concept of a number is an abstraction. Comprehensive articles may be forced to use abstract language because that language is the only language available to give a correct and thorough description of their topic. Because of this, some parts of some articles may not be accessible to readers without a lot of mathematical background. If you believe that an article is overly abstract, then please leave a detailed comment on the talk page. If you can provide a more down-to-earth exposition, then you are welcome to add that to the article. Why don't Misplaced Pages's mathematics articles define or link all of the terms they use? Sometimes editors leave out definitions or links that they believe will distract the reader. If you believe that a mathematics article would be more clear with an additional definition or link, please add to the article. If you are not able to do so yourself, ask for assistance on the article's talk page. Why don't many mathematics articles start with a definition? We try to make mathematics articles as accessible to the largest likely audience as possible. In order to achieve this, often an intuitive explanation of something precedes a rigorous definition. The first few paragraphs of an article (called the lead) are supposed to provide an accessible summary of the article appropriate to the target audience. Depending on the target audience, it may or may not be appropriate to include any formal details in the lead, and these are often put into a dedicated section of the article. If you believe that the article would benefit from having more formal details in the lead, please add them or discuss the matter on the article's talk page. Why don't mathematics articles include lists of prerequisites? A well-written article should establish its context well enough that it does not need a separate list of prerequisites. Furthermore, directly addressing the reader breaks Misplaced Pages's encyclopedic tone. If you are unable to determine an article's context and prerequisites, please ask for help on the talk page. Why are Misplaced Pages's mathematics articles so hard to read? We strive to make our articles comprehensive, technically correct and easy to read. Sometimes it is difficult to achieve all three. If you have trouble understanding an article, please post a specific question on the article's talk page. Why don't math pages rely more on helpful YouTube videos and media coverage of mathematical issues? Mathematical content of YouTube videos is often unreliable (though some may be useful for pedagogical purposes rather than as references). Media reports are typically sensationalistic. This is why they are generally avoided.

This is the talk page for discussing WikiProject Mathematics and anything related to its purposes and tasks.
Archives: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73Auto-archiving period: 15 days 

Misplaced Pages:Misplaced Pages Signpost/WikiProject used Template:Misplaced Pages ad exists


WikiProject Mathematics archives ()
Earlier years


This page has archives. Sections older than 15 days may be automatically archived by Lowercase sigmabot III.
Edit this box

Strange editor

Please look at these edits: Special:Contributions/Hanumantw; not vandalism, but... something strange? Boris Tsirelson (talk) 16:07, 11 August 2019 (UTC)

It may not be deliberate destruction motivated by hatred of the good, but damaging things as a result of carelessness or ignorance can be just as harmful. JRSpriggs (talk) 01:21, 12 August 2019 (UTC)
Now blocked indefinitely. Boris Tsirelson (talk) 08:15, 17 August 2019 (UTC)

Australian IP edit-wars in Quaternion

Insists that knows the only correct notation and the rest of the world the preceding version is “wrong”. Look at https://en.wikipedia.org/search/?title=Quaternion&action=history&offset=2019081216&limit=9 and talk:Quaternion‎‎ #Exponential, logarithm, and power functions, please. Incnis Mrsi (talk) 15:42, 12 August 2019 (UTC)

Very depressing bug in the editor

I was editing Talk:Axiom of union#Independence of the axiom of union. I had planned out what I wanted to say in my head and was rushing to get it committed to writing before I forgot it. As usual, there were times when I needed to look at another article to get the correct spelling or latex symbol. This time, I went to the Axiom of powerset to get the symbol for the powerset. I had to enter the editor to see the source of that article to get "\mathcal (P)". When I tried to back out of that edit and return to my original edit, it would not allow me to do so. Ultimately, I had to "resend" to escape and as a result I lost most of what I had already written. I cannot say in words just how discouraging this is. For several minutes I sat stunned, enervated, unable to do anything. Eventually, I forced myself to re-enter an approximation to what I had written before.

This is not the first time this has happened. It has happened several times before. But it is infrequent enough that I forget to take precautions against it. Is there some way to get this bug fixed? JRSpriggs (talk) 01:20, 13 August 2019 (UTC)

Which editor(s) are you using? It may make a difference. I haven't had problems except when my browser exceeded available memory on my machine and locked up.... 01:36, 13 August 2019 (UTC)
(edit conflict × how ironic) Not quite sure I'm following your steps exactly. Do you mean that from the edit window, you went directly to another article (maybe via the search bar), and then hit the back button on your browser only to find that it hadn't saved the state of what you were doing? If so, then that's not really a bug; there's no guarantee that a browser will keep the current state of what you're doing cached if you move forward to another page. Ideally it will try to, especially for simple stuff, but that's not something you can rely on. On the other hand, if you go browsing in another tab or window, then all should be fine, but if not, it's likely browser-related, not a Mediawiki issue. Or have I misunderstood what the problem is? –Deacon Vorbis (carbon • videos) 01:42, 13 August 2019 (UTC)
To Arthur Rubin: I was just using the normal editor provided by Misplaced Pages, the old one, not the visual editor.
To Deacon Vorbis: Yes, I think you got it right. My browser is Firefox. I was thinking that there are three things I might do to work around this: (1) copy the source of my edit into a file on my disk before going on such expeditions, just in case this happens; (2) do the search and cutting (before pasting) in another copy of Firefox; or (3) save my edit before I am really done and then edit again after I have done the search. What do you recommend? JRSpriggs (talk) 06:13, 13 August 2019 (UTC)
This depends on the browser, and even on the browser version. With Safari, non-saved edits are sometime lost, sometime not lost when one come back to a page with the back button. If one has left the page after clicking "show preview", edits are sometimes kept, but with the most recent versions they are kept only if one does almost nothing (no search in the page, no diff, no look to the source, ...) with the visited page(s). Therefore, I have now the habit to use another tab for navigation during an editing process, and, when searching or following a link from the edit window, to to it with the right button and "open the link in another tab". D.Lazard (talk) 07:51, 13 August 2019 (UTC)
That's more or less my habit as well. XOR'easter (talk) 15:22, 13 August 2019 (UTC)
To Lazard: Thanks for the suggestion. I will try the right-click on a link to get a separate tab method. JRSpriggs (talk) 01:29, 14 August 2019 (UTC)
I’m late but I can confirm I had the same type of (very disheartening) experiences before on multiple occasions; they may have been in Misplaced Pages or some other website. Since I couldn’t figure out the behavior (how unsubmitted text is handled), my habit has been to copy large text into the clipboard before hitting submit (if edits are small, I don’t bother). —- Taku (talk) 22:54, 17 August 2019 (UTC)

Factorial and double exponential

See recent history of factorial. An editor there insists that the constant function f(x)=1 is an example of a double exponential function and on using that example to change the statement that the factorial grows "slower than double exponential functions" to the overly-pedantic "slower than many double exponential functions e.g. (example)". I don't think this is an improvement, but additional opinions might be more helpful than my repeated reversion of these edits. —David Eppstein (talk) 22:46, 17 August 2019 (UTC)

Puzzled by watchlist

This WPM talk page is on my watchlist, in the sense that I do see the corresponding blue star between "View history" and "More". And nevertheless it does not appear on my watchlist. This is a new phenomenon (the last week or two). Mostly, my watchlist looks as before; but some items are missing, I do not know why. If I click the blue star ("remove this page from your watchlist") and then click the (no more blue) start again (making it blue again), it helps; the page returns to my watchlist. But afterward it disappears again. Why so? Boris Tsirelson (talk) 06:51, 19 August 2019 (UTC)

Or maybe not quite so. I just tried to click twice the star on Talk:Normal distribution (edited by me yesterday, and by a bot today); it did not help. Boris Tsirelson (talk) 06:57, 19 August 2019 (UTC)

Empty square root

The empty square root {\displaystyle {\sqrt {\;}}} generated as <math>\sqrt{\;}</math> is very badly aligned (I have found this in nth root). The reason seems that the alignment is done on the center of the argument and that the space character is viewed as a zero-height character placed at the bottom of the line. For having a normal alignment such as       , {\displaystyle {\sqrt {{~^{~}}^{~}\!\!}},} I have used <math>\sqrt{{~^~}^~\!\!}</math>. Do someone know a less weird method for a similar result? D.Lazard (talk) 07:42, 19 August 2019 (UTC)

P.S. A similar result ( x {\displaystyle {\sqrt {\color {white}{x}}}} ) is obtained with <math>\sqrt{\color{white}{x}}</math>, but it is also semantically doubtful. D.Lazard (talk) 07:54, 19 August 2019 (UTC)
Try <math>\surd</math>, giving {\displaystyle \surd } . No horizontal bar, but it does better align it with the text. If WP handled real TeX, \sqrt{\phantom{x}} or \sqrt{\hspace{1em}} would be reasonable ways to create an empty square root.--{{u|Mark viking}} {Talk} 08:14, 19 August 2019 (UTC)

Convex hull lower bound

Please see Talk:Convex_hull_algorithms#Lower_bound_on_computational_complexity --GunterS (talk) 08:43, 21 August 2019 (UTC)

Already answered there. D.Lazard (talk) 09:21, 21 August 2019 (UTC)

Cocycle of a group action

It is a pity that cocycle of a group action is not treated; neither in "Cocycle", nor in "Group action (mathematics)". See Talk:Cocycle#Cocycle of a group action. Boris Tsirelson (talk) 08:22, 24 August 2019 (UTC)

Pollard algorithms

Are Pollard's rho algorithm for logarithms and Pollard's kangaroo algorithm about the same thing? Bubba73 15:35, 24 August 2019 (UTC)

I am not acquainted with these; but in "Pollard's kangaroo algorithm" I read: "Pollard's kangaroo algorithm ... introduced ... in the same paper as his better-known Pollard's rho algorithm"; if so, then they are two different algorithms "for solving the same problem". Boris Tsirelson (talk) 17:21, 24 August 2019 (UTC)
The way it seems to me is that Pollard's rho algorithm is for factoring numbers and the other two use a similar method for finding discrete logarithms. Bubba73 18:09, 24 August 2019 (UTC)

Draft:Genus of a group

Is this a topic that deserves a separate article? Genus (mathematics)#Graph theory already covers the topic but a quick Google search shows the topic is of independent interest. (I admit I’m not a specialist on this area so the others might know better.) — Taku (talk) 22:52, 26 August 2019 (UTC)

No separate IMHO, but definitely as little as redirect to Cayley graph, especially because the article already mentions the genus of it (albeit without a wiki link). Incnis Mrsi (talk) 16:21, 27 August 2019 (UTC)
Where in Cayley graph is the genus of a Cayley graph discussed? --JBL (talk) 17:09, 27 August 2019 (UTC)
In fact, nowhere the genus of the graph (I suffered a glitch). Anyway the concept is defined via Cayley graphs and may deserve a section there. Incnis Mrsi (talk) 17:24, 27 August 2019 (UTC)