Wikipedia talk:WikiProject Mathematics/Archive/2010/Feb

Mathematical assumption

The new page titled mathematical assumption is a mess. Michael Hardy (talk) 06:20, 27 January 2010 (UTC)

I've prodded it. --Trovatore (talk) 06:27, 27 January 2010 (UTC)

The prod was contested and they added a justification to the talk page.--RDBury (talk) 17:34, 27 January 2010 (UTC)

It now redirects to axiom, but a hypothesis in the statement of a theorem is a "mathematical assumption" but not generally an axiom. Michael Hardy (talk) 02:11, 29 January 2010 (UTC)

That's true; it isn't a perfect solution. I mused on the talk page that I was not sure whether to redirect to axiom or take it to AfD. Someone else went ahead and redirected, after which I no longer felt strongly enough to bother with it anymore. If someone else wants to, I have no objection. --Trovatore (talk) 02:21, 29 January 2010 (UTC)

I was the one who redirected. I don't feel particularly strongly about this, either; but I thought that the redirect was much better than what was previously on that page. I wouldn't object if someone wants to delete mathematical assumption, nor if someone wants to create a new and better article there. Ozob (talk) 15:10, 30 January 2010 (UTC)

I wouldn't object to deletion, but I have trouble imagining an article under that title that I wouldn't want to delete. It's a bad habit to start writing articles about phrases whose meanings are more or less clear from their component words. --Trovatore (talk) 09:42, 31 January 2010 (UTC)

Red cats

Is there any reason to add categories to redirect articles? I wouldn't care except they're causing these articles, e.g. Subnormal series, so show up in current activity and List of mathematics articles when they shouldn't be there.--RDBury (talk) 17:02, 29 January 2010 (UTC)

They should not be: see WP:RCAT. I've checked and fixed that one. --JohnBlackburne^words_deeds 17:09, 29 January 2010 (UTC)

Thanks, I'll fix any other ones I come across.--RDBury (talk) 18:09, 29 January 2010 (UTC)

There are good and bad reasons to add categories to redirects. If I had added one for a good reason I'd be unhappy if it was just taken off. I can't offhand think of obvious examples in mathematics. Charles Matthews (talk) 23:00, 29 January 2010 (UTC)

Example: Harborth graph, a redirect to Matchstick graph, is in Category:Individual graphs. The Harborth graph is an individual graph that should be mentioned within that category, but is currently described within the matchstick graph article rather than having its own article. Matchstick graphs are a general family of graphs that should not be in that category because the category is for individual graphs rather than graph families. Putting the category on the redirect means that the category entry is displayed with the name that's appropriate for the category listing. —David Eppstein (talk) 23:25, 29 January 2010 (UTC)

The exceptional cases are listed in WP:RCAT.--RDBury (talk) 15:08, 30 January 2010 (UTC)

Right, so this one is a clear case of "Redirects whose target title is incompatible with the category" and contradicts your blanket statement at the start of this thread that categories should not be added to redirects. —David Eppstein (talk) 15:56, 30 January 2010 (UTC)

Actually that wasn't my statement. But the simplistic version is, if the cat works for the target then add it there, if not then add it to the redirect.--RDBury (talk) 16:15, 31 January 2010 (UTC)

Sorry, I meant JohnBlackburne's statement. —David Eppstein (talk) 19:40, 31 January 2010 (UTC)

Yes, sorry, my statement oversimplified it somewhat. WP:RCAT says that in general redirects should not be categorised, with a few exceptions. None I think applied to the redirect that started this discussion, which simply caused the article to be listed twice in the same category. But there are exceptions, in particular where the redirect is to something in the article that should be categorised differently to the article as in the above example.--JohnBlackburne^words_deeds 20:16, 31 January 2010 (UTC)

Edit war at Euclid

In case anyone cares, there is (or was) a rather silly edit war going on at Euclid (talk).--RDBury (talk) 00:19, 1 February 2010 (UTC)

Multiplicity-one theorem

Multiplicity-one theorem is a new article written by someone clearly unfamiliar with Wikipedia usage conventions. It seems to be about group representation theory. Could someone who knows the topic and also knows Wikipedia usages help? Michael Hardy (talk) 04:48, 1 February 2010 (UTC)

I'll fix it up a bit before going to bed, and work on it more tomorrow if need be. RobHar (talk) 05:37, 1 February 2010 (UTC)

Advanced calculus

We have no article titled advanced calculus. We never have. (We admins get to see deleted versions if they exist, and in this case they don't.) Should we? Michael Hardy (talk) 04:26, 31 January 2010 (UTC)

Is there a standard definition? (I doubt it; each textbook seems to have its own.) Septentrionalis PMAnderson 05:00, 31 January 2010 (UTC)

I don't see a need for that article. What would it contain? CRGreathouse (t | c) 06:11, 31 January 2010 (UTC)

I don't see the lack of a standard definition as an objection to the existence of the article. (Is there a standard definition of "justice"?) But it should be mentioned in the article. Michael Hardy (talk) 06:39, 31 January 2010 (UTC)

BTW, the only course I've taught with "advanced calculus" in the title was more off-the-beaten-path than most. Its content was dictated by the instructors of certain fluid dynamics courses for which it was an essential prerequisite. Half of it was differential equations including Sturm–Liouville theory and generalized Fourier series. I kept wondering if one of the engineering graduate students who were the only demographic there would ask how you know there are "enough" eigenfunctions. No one ever did. The other half was complex variables. After I had mentioned that Cauchy was a 19th-century French mathematician and Liouville was a 19th-century French mathematician, and I think there were one or two more of those, I mentioned the residue theorem, and one student was prepared to hear that Residue was a 19th-century French mathematician.

Maybe the lack of a standard definition of the topic could be the article's main point. Michael Hardy (talk) 06:49, 31 January 2010 (UTC)

There are also courses "Advanced set theory" and "Advanced probability" in our university; so what? Should WP have such articles? Boris Tsirelson (talk) 07:35, 31 January 2010 (UTC)

Well, we have articles on some other standard curriculum elements, pre-algebra and such. But I do think those are a bit more standardized. At Caltech, Advanced Calculus was basically a baby real analysis course. At other schools it may be more about specific methods. --Trovatore (talk) 07:55, 31 January 2010 (UTC)

There are plenty of textbooks titled "advanced calculus" [1]. Whether there's any consistent subject that they all cover is a different question that's harder for Google to answer quickly. —David Eppstein (talk) 07:56, 31 January 2010 (UTC)

I've taught advanced calculus. As I recall the curriculum covers multivariable and vector calculus in 2 and 3 dimensions, Green's, Stoke's and similar theorems, Taylor's series in multiple variables, not sure what else (it's been a while). Basically anything a sophomore engineering major ought to know about math, but excluding complex variables. I'm not convinced we need articles based on textbook titles; usually these are based on typical college course titles which depend on how material can be divided up into semester long chunks, not on anything to do with the subject matter.--RDBury (talk) 15:58, 31 January 2010 (UTC)

+1--Kmhkmh (talk) 16:03, 31 January 2010 (UTC)

It seems clear enough that "advanced calculus" is a topic in mathematical pedagogy, rather than in mathematics. Such as pre-algebra, for example. Charles Matthews (talk) 17:03, 31 January 2010 (UTC)

I agree. Michael Hardy (talk) 18:00, 31 January 2010 (UTC)

Kmhkmh: Your list of topics looks to me like that of what I think of as "sophomore (i.e. 2nd-year) calculus", whereas what I think of as "advanced calculus" comes after that. Michael Hardy (talk) 18:01, 31 January 2010 (UTC)

I think you mean RDBury? I didn't list anything at least.--Kmhkmh (talk) 01:15, 1 February 2010 (UTC)

Sorry---that's who I meant. Your terse cryptic comment following his comments confused me. Michael Hardy (talk) 05:58, 2 February 2010 (UTC)

"+1" is common shorthand for I agree (completely)--Kmhkmh (talk) 07:04, 2 February 2010 (UTC)

There are two different meanings to "advanced calculus" that I have seen. The first is what some schools call "calculus 4", which covers about what RDBury listed: Taylor series, the implicit function theorem and its uses, Fourier series, etc. The other is a course that covers Calculus I but with proofs. — Carl (CBM · talk) 18:52, 31 January 2010 (UTC)

Following the usual standard shouldn't 'Advanced calculus' mean it is elementary and 'Elements of' or 'Introduction to' require a university degree to approach them? :) Dmcq (talk) 19:13, 31 January 2010 (UTC)

Yeah..... Basic Algebra I is for graduate students in mathematics; Advanced Algebra is a remedial high-school course for university students who will never learn what "theorems" or "algorithms" are. Michael Hardy (talk) 06:00, 2 February 2010 (UTC)

George Kayatta

The article titled George Kayatta has a bit more of the element of honesty than it did recently, but could still use some work. For example, it reported that he had been recognized as a "Renaisance Man" (two capital letters). When asked who had recognized him thus (Oxford University? The Pope? His sixth-grade teacher?) someone added a source: a magazine article. Did the magazine bestow that recognition? In fact, the magazine reported that he refused to appear on TV unless introduced in that way. Then it linked to a talk by a mathematician saying, allegedly, that his discoveries would revolutionize mathematics. If you look at that talk, it's about crackpots, one of whom says pi is 25/8, another of whom says the sun is made of ice, and what it says about Kayatta is that someone else (identity unspecified!) said Kayatta's work would revolutionize mathematics. The article could use some more work....... Michael Hardy (talk) 03:06, 1 February 2010 (UTC)

Since this post the article was nominated for deletion.--RDBury (talk) 09:55, 1 February 2010 (UTC)

Wolf Prizes

2010 Wolf Prizes in Mathematics for Dennis Sullivan and Shing-Tung Yau, according to a news agency link on the Sullivan page. Articles to watch and improve, therefore. Charles Matthews (talk) 14:22, 2 February 2010 (UTC)

The Yau page is being actively edited, and some effort is going to be needed to ensure NPOV. Charles Matthews (talk) 16:23, 3 February 2010 (UTC)

There have been large-scale additions of material that is not encyclopedic in tone. Please help out. This article is a BLP, and must adhere strictly to Verifiability and Neutrality policies. Charles Matthews (talk) 16:46, 4 February 2010 (UTC)

Table of costs of operations in elliptic curves

Table of costs of operations in elliptic curves has been prodded. It was written by someone pretty much wholly unaware of Wikipedia usage conventions. I suspect it can be cleaned up. Michael Hardy (talk) 07:46, 4 February 2010 (UTC)

Unprodded, anyway. The material is indeed technical, but elliptic curve crypto is out there on websites with your credit card details. Charles Matthews (talk) 08:30, 4 February 2010 (UTC)

One problem with the article as it stands is that without sources it is very difficult to verify the operational time-cost values given for each curve representation. They do not seem to follow in any obvious way from the definitions of the group operations for the respective curve representation. Gandalf61 (talk) 10:18, 4 February 2010 (UTC)

The definition of cost in the table looks screwy. Inversion = 100 multiplications? Maybe that's true for some computer architecture somewhere, but surely that's not true for every computer architecture everywhere. Is this some sort of crypto-community heuristic? If so it deserves an explanation. Ozob (talk) 12:30, 4 February 2010 (UTC)

This was created by the same person mentioned earlier, current research in cryptography. As I said earlier, notability is marginal and in this case the article is unreferenced and possibly OR. There are plenty of articles whose notability is certain and need to be worked on. To me, those have a higher priority. If you're going to work on an article that has no references then the you should add them before doing anything else. Making everything look nice isn't worth anything if you can't verify the information.--RDBury (talk) 15:32, 4 February 2010 (UTC)

Certainly the article should be referenced. I have a little problem with your general attitude, though. I have referenced literally hundreds of articles in 2010. I happened to apply format to this one, while adding {{unreferenced}}. Where, exactly, is your problem with that? If you happen to be an authority on crypto I will of course defer to you on that matter. I think, as a matter of fact, I do not actually share your priorities in developing Wikipedia, since I have set a high store on creating content for the past six and half years rather than carping about it; but on some matters editors can agree to differ. Charles Matthews (talk) 15:53, 4 February 2010 (UTC)

Perhaps my attitude was a bit overly critical. I'm just tired of seeing articles with dozens if not hundreds of edits and yet still no one has bothered to find references. Then, often when you read the article it looks like someone's vague recollections of a calculus class they took ten years ago rather than an encyclopedia article and it's clear that no one did any actual research for it. I would like this project to be something I can take pride in. So when I see a poorly written article with little useful information I tend it take it a bit personally, especially when that article is seen by hundreds of people a day. So fixing articles like that is, for me at least, what people should be spending time on. I've done my share of work on obscure subjects too, but they're ones I'm interested in and everyone needs some fun. As for spending most of my time carping, actually right now I'm spending most of my time of the Curve article which despite having been created eight years ago and being viewed by a couple hundred people a day, can still use a lot of work.--RDBury (talk) 17:16, 4 February 2010 (UTC)

There's a survey of the field from a few years ago at http://eprint.iacr.org/2007/441.pdf. What is posted in the table may be from someone's unpublishable dissertation, or compiled from this and other things on the "Explicit-Formulas Database" at http://www.hyperelliptic.org/EFD/. That is the real issue. I've just left a note at Wikipedia talk:WikiProject Cryptography about it. The "Database" carries no license or copyright information, and one concern should be that some of the related curves articles borrow too much from it. Charles Matthews (talk) 19:13, 4 February 2010 (UTC)

Quintuple

Can any expert check out all the following:

1. The info at Number prefix#References about the words quadruple and quintuple
2. The info at Tuple#Origin of name
3. The discussion at Talk:Tuple that nobody but me and User:Cybercobra has been into

I would like to note the disagreement about the origin of the word quintuple in the 2 articles. Georgia guy (talk) 21:47, 4 February 2010 (UTC)

Fixed, I hope, from the OED and a Latin dictionary. Quintuple is not a mistake, it simply arose in the thirteenth century. Septentrionalis PMAnderson 05:37, 5 February 2010 (UTC)

Mistake in Theorem?

The article theorem says:

Logically many theorems are of the form of an indicative conditional: if A, then B. Such a theorem does not state that B is always true, only that B must be true if A is true. In this case A is called the hypothesis of the theorem (note that "hypothesis" here is something very different from a conjecture) and B the conclusion (A and B can also be denoted the antecedent and consequent). The theorem "If n is an even natural number then n/2 is a natural number" is a typical example in which the hypothesis is that "n is an even natural number" and the conclusion is that "n/2 is also a natural number".

I've the feeling there is subtle a mistake: the typical example is not in the form if A, then B, it's in the form for any x if A(x) then B(x), and this is true for the majority of the theorems. It would be rather strange to find a theorem which says if A, then B where A and B are closed formulas. What do you think?--Pokipsy76 (talk) 17:14, 3 February 2010 (UTC)

This should probably be discussed at Talk:Theorem.

You're right that it's unusual to have a theorem of the form "if A, then B" for sentences A and B -- this would be a conditional theorem. But if you let A be f(x) and B be g(x) where x is free in f and g, then "if A, then B" is a perfectly acceptable form.

CRGreathouse (t | c) 19:44, 3 February 2010 (UTC)

Yes but this happens only because of the convention to consider free variables as universally quantified.--Pokipsy76 (talk) 20:31, 3 February 2010 (UTC)

It's more than convention, really; it's considered an axiom in some formal systems (e.g., it's Metamath's ax-gen). The intuition is that if you can prove f(x) without using x, then it's true regardless of which x you pick and so true for all x. CRGreathouse (t | c) 21:05, 3 February 2010 (UTC)

Ok I think you are right, but don't you think that the text is potentially misleading? I say this because I recently had to do with people who were studying material implication and came to the conclusion that typical theorems of mathematics (of the form "A->B") were comparable to sentences "P->Q" where P and Q are any couple of true independent statements (and the wikipedia page theorem was cited in this context).--Pokipsy76 (talk) 09:08, 5 February 2010 (UTC)

In ZF, one might say that if the axiom of choice holds, then such and such is true. This does not use any common variable "x".

If "Q" is a true sentence and "P" is any meaningful sentence, then "P->Q" is true. It is just not particularly interesting or useful. JRSpriggs (talk) 02:41, 6 February 2010 (UTC)

Sure, so what if we write «Logically many theorems are of the form of an indicative conditional: if A(x), then B(x), where x stands for a generic mathematical object of some kind.»? Too technical?--Pokipsy76 (talk) 09:12, 6 February 2010 (UTC)

I think you have a point, Pokipsy76. But I'm not too keen on your current suggestion and I don't have a better wording. CRGreathouse (t | c) 03:29, 7 February 2010 (UTC)

Project Redirects

If there's no rule against project redirects, I think Wikiproject:Mathematics and Wikiproject:Math should be created as redirects to this project. I doubt there would be any controversy over those names being taken for aliases. LokiClock (talk) 14:07, 5 February 2010 (UTC)

Creating new cross-namespace redirects is generally disapproved of at the moment. Only three wikiprojects have such redirects, so it's not like people are going to expect them and try to use them. We have redirects at WP:WPM, WP:WPMATH and WP:Mathematics, and WP:MATH and WP:Math point to Help:Displaying a formula, which has a hatnote. I think that's enough. Algebraist 16:00, 5 February 2010 (UTC)

Agree. Paul August ☎ 16:29, 5 February 2010 (UTC)

Maybe what the original poster meant was Wikipedia:Wikiproject Mathematics and Wikipedia:Wikiproject Math? Michael Hardy (talk) 23:04, 5 February 2010 (UTC)

No, I meant what I indicated. I misread the group name as Wikiproject:Wikiproject Mathematics, which would of course be a silly name. LokiClock (talk) 17:45, 6 February 2010 (UTC)

Possible improvements of <math>: links

I have some thoughts how to improve rendering of mathematical formulae in Wikipedia.

First, to allow a link from a mathematical symbol inside a formula, something like that

<math>\link{smooth function}{C^\infty}(\link{sphere}{S^2},\link{real numbers}{\mathbb R})</math>

will produce: C^∞(S², ℝ) .
I know, it is extremely difficult for rasterized output, but it would be helpful even if this will work with HTML and MathML output.

It would be also useful if any <math>-formula had internal link to Mathematical notation article by default, unless this formula contains an internal link, the link turned off by special tag parameter or in user preferences. Such link is similar to {{IPA}} for phonetic transcription. The style of the link on (or inside) a formula must be not underlined, bordered or so, indeed. The article “mathematical notation” in this case should contain much more explanations, like a corresponding article in ru.wiki which is currently far from completeness, though.

Incnis Mrsi (talk) 22:00, 6 February 2010 (UTC)

There is another possibility, alternative to linking to “mathematical notation” directly. When clicking to a formula, run a popup (JavaScript or so) trying to grammatically parse the formula and give to a user some DHTML output with necessary links. Incnis Mrsi (talk) 22:22, 6 February 2010 (UTC)

As you've noted it will be difficult to do this with rasterised images, and difficult to know when that's needed as an arcane combination of browser, user settings and the complexity of the math determines what gets rasterised.

But I'd also question how often you want to do it. E.g. in the example the choices over what and where to link to are to some extent arbitrary. Why not link to infinity for example. More generally if you feel the need to explain notation it should be done separately, e.g. "where C^∞ is a smooth function...". The elements of a formula are often small making it difficult to spot links, to see where one ends and another begins, and for some users (e.g. when using a touch-pad or screen) difficult to precisely place the cursor to select them. Unless it's the whole formula I'd say it's a bad idea, and even the whole formula might be better done with e.g. a text link after. --JohnBlackburne^words_deeds 22:36, 6 February 2010 (UTC)

It is already possible to link the whole formula (even though it does not look like a link on the first sight): $C^{\infty }$. — Emil J. 12:13, 8 February 2010 (UTC)

I think it is better to avoid links within formulas, and just explain the symbols in the surrounding text. On one hand, English is very flexible for explaining exactly what is happening in each article. And we have a lot of experience explaining formulas in print, where there are no hyperlinks.

On the other hand, I am afraid of people going around adding "missing" links that are of little value or are even misleading. For example, I might see this in the context of Hindman's theorem:

Color the elements of $2^{<\infty }$ with k colors

It would be tempting, but very wrong, to link that infinity sign to an article on infinity. (What the symbolism means is to color every finite sequence of 0s and 1s). — Carl (CBM · talk) 13:00, 8 February 2010 (UTC)

There's another reason as well to make the link and the description in the surrounding text rather than in the formula: getting changes made to the underlying Wiki code and propagated to Wikipedia can be very difficult, whereas links in surrounding text are available now. —David Eppstein (talk) 15:59, 8 February 2010 (UTC)

Wikipedia:Articles for deletion/George Kayatta

Wikipedia:Articles for deletion/George Kayatta.

I'm not really sure this concerns the mathematics WikiProject. Until recently the article said that this alleged genius has contributed to mathematics (among many other things). Now it says he claims to have contributed to mathematics. Underwood Dudley wrote a book about mathematical crackpots in which he devoted a whole chapter to this guy—hence some asertiosn of notability. The discussion looks as if it may be heading for a "no consensus" outcome, the immediate result of which is that it is kept rather than deleted. (I'm not even sure whether it should be kept, but if it is, I might try to improve it—in particular see if one can document some of the claims.) Michael Hardy (talk) 18:37, 7 February 2010 (UTC)

Nitpick: the book devotes a whole chapter to megalomaniacs, of which Kayatta is only one example out of 3-4. But Kayatta is the only one explicitly named at the end of the book, while the others are referred to by initials only. (In the chapter Kayatta is referred to as G. K. or just K.; at the end his name is called out.)

CRGreathouse (t | c) 21:44, 7 February 2010 (UTC)

Dimensionality again

The names in Template:Polytopes, and the general expansion of higher-dimensionality articles, needs some help. (Is there a WikiProject Geometry? That might be a better place to put that.)

In regard Template:Polytopes, I suggest removing the 1-polytope entry, and writing the rest something like:

2 (Polygon){{.}}3 (Polyhedron){{.}}4 (Polychoron}{{.}}5{{.}}6{{.}}7{{.}}8{{.}}9{{.}}10

My proposal for much of the dimensionality articles:

Most of the articles are now at "en-dimensional space". (For example, when n=5, by "en-dimensional space" I mean five-dimensional space.

1. Split out "enth dimension" for ideas referring to that dimension in common usage; much of fourth dimension really is of that form.
2. Move "en-dimensional space" to "n-dimensional space".
3. Move those parts of "en-dimensional space" about polytopes to "n-polytope", and summarize in the main article.
4. Move much of those parts of "en-dimensional space" which do not depend on the value of n to n-dimensional space there, and possibly summarize.
5. Move those parts of "n-polytope" which do not depend on the value of n to polytope, and possibly summarize.

There may be other "obvious" changes which should be made, but I don't want to revert the prolific editor 4, without some consensus. — Arthur Rubin (talk) 17:23, 8 February 2010 (UTC)

I jumped in, since I added most of the content of the n-polytope articles. I removing the dimensional names from the template above 3, and removing 1-polytope entirely. Most of my work has been related to uniform polytopes, and I've moved content of these for 4,5,6 to separate articles. The dimensional specifies of the uniform polytopes are most apparent by symmetry classes, while other contexts specifics by dimension are not clear to me. Tom Ruen (talk) 03:48, 9 February 2010 (UTC)

Use of Matlab code in articles

This has come up here, but I've noticed it on other pages. Should Matlab code be used in maths articles? Few people have access to the program because of its price, and judging by the sample code in simplex it's of little help to those who don't use Matlab, as the syntax is unlike other programming languages but also unlike symbolic maths. It obviously is used by some people otherwise it would not have been added, but I suspect it's only used by a minority of editors and an even smaller fraction of readers.

Should Matlab code be used at all? Is there anything it can be replaced with, such as a less proprietary language, that more people are familiar with or have access to? I think the answer may be different in different cases, i.e. if Matlab has been used because of it's mathematical strengths it might be difficult to replace. But if as in simplex it is just being used to manipulate numbers and vectors then any modern programming language could be used, or the article could just give a clear explanation which any technically minded reader could implement.--JohnBlackburne^words_deeds 10:35, 2 February 2010 (UTC)

I'm very unkeen on programming language code being stuck in, I'd prefer a longer winded pseudo code myself. It shouldn't be too hard to turn the code into an english description with indenting to group bits. Dmcq (talk) 11:06, 2 February 2010 (UTC)

I think the article in question already has descriptions, so those could be improved and the code removed. I am generally not in favor of adding source code to "pure" articles such as simplex. For example, I would not like to see source code in group (mathematics) even though there are lots of computations one could do for groups. For a few articles on the subject of computability, or for articles on numerical methods, pseudocode can be appropriate, though. — Carl (CBM · talk) 11:23, 2 February 2010 (UTC)

Second that. It's hard to see, useful or not, how actual code isn't either OR or COPYVIO. Pseudocode describes the algorithm and the readers can do their own implementation in whatever language they wish. Plus, no matter how readable a computer language is, if you don't know it then interpreting the code is going to be a matter of guesswork. The only time I can see that code should be used is for example code for an article about the language itself. Btw, if there is any kind of consensus on this issue can we add it to WP:MOSMATH so result won't disappear into the archives? This has appeared before at Wikipedia:Village pump (miscellaneous)/Archive 19#Source code written by editors. --RDBury (talk) 11:42, 2 February 2010 (UTC)

There's no such thing as copyvio of math formulas, regardless of what formal language is used to represent them. that being said, i think the c (programming language) would be more universal. though i understand that, not being an array programming language, some things would be more complex. also its math function library ("math.h") probably isn't as extensive as matlab's. Kevin Baas^talk 16:39, 2 February 2010 (UTC)

I agree, I have no problem with code as OR or COPYVIO. Within reason it's just a way of presenting an example, which is allowed and encouraged to make articles more accessible. The problem is coming up with a language that's suitable. In theory you could do everything in C, but even arrays are a lot of work in C. But any other language is likely to be less familiar and/or less standardised, especially if it uses specialised math or plotting techniques.

I've fixed one of the instances in simplex by rewriting it so the sample is much easier to follow and removing the Matlab code altogether. There's another chunk in there which I've left in as it's in an area I'm less familiar with, though I've added some syntax colouring which at least makes it more readable. The thing to use seems to be:

<syntaxhighlight lang="matlab"> ... </syntaxhighlight>

It would be good to do this to any Matlab (or any other code) samples so they are easier for especially people not familiar with Matlab to follow, if it cannot be removed or replaced straight away. --JohnBlackburne^words_deeds 17:30, 2 February 2010 (UTC)

Code is not the same as a formula. Look at the Tower of Hanoi article for example. It has long sections of code in several languages which are either take directly from a book or magazine (COPYVIO) or an editor wrote the code in which case it can't be verified (OR). Plus, I don't know the languages used so a good chunk of the article is complete gibberish to me; it's hard to argue that it's helping the make the article more understandable. Even if code were a good idea, C is a bad choice because it tends to be terse and unreadable. For example the article I mentioned uses "the mth move is from peg (m&m-1)%3 to peg ((m|m-1)+1)%3". I was a C programmer fo 2 years and I have a hard time understanding it; is a reader who doesn't know C supposed to make any sense at all from it? Encyclopedia articles are supposed be accessible to as wide an audience as possible, yet here we have an article about a children's toy that requires a degree in computer science to understand. If you make the claim that is not COPYVIO or OR then give an example where it isn't and if you think it may make an article easier to understand then give an example where it does.--RDBury (talk) 18:45, 2 February 2010 (UTC)

(ec) The COPYVIO discussion was covered by RDBury above, better than I did in my attempted comment. .

As for Matlab, I agree that, where it doesn't reflect standard mathematical notation, it probably shouldn't be in articles, except on Matlab itself or Matlab packages. (I say this as someone who has used Matlab for over 14 years.) — Arthur Rubin (talk) 18:54, 2 February 2010 (UTC)

I could write a program in any computer language to generate all the possible programs in all known computer languages (or ones that i know at least) that do the tower of hanoi, and i'm sure many of them would be exactly the same as are in a book or magazine. does that mean my computer program should go to jail / pay a fine? Fine, you know what, I'll make up my own formal language and state it there. No difference. exactly my point. and you know what? my first attempt at writting a tower of hanoi program would probably turn out to be exactly the same as in a book somewhere. just like my first attempt at an algorithm to add two numbers would. see the problem there? i'm sure we could go over the differences between algorithms and formulas, but none of them would be relevant. But as mentioned, this topic was covered above and probably ad nasuem elsewhere in wikipedia. so let us not digress. the issue is: what formal language should we write our ironically simultaneously both OR and COPYVIOs in? Kevin Baas^talk 19:05, 2 February 2010 (UTC)

A text to be understood by a man should be written in an informal language. A formal language is for a text intended for a computer. (Among programming languages I prefer Python, but this is irrelevant.) You may object: math formulas are a formal language, but intended for a man. Well, we do use formulas in WP, but only as a rather short insertions (half a line, sometimes several lines, but not more). An algorithm should not be longer in a WP article, I think so; otherwise, its informal idea should be written. Boris Tsirelson (talk) 20:31, 2 February 2010 (UTC)

I think there is occasionally a place for programs. Sometimes they're good for making things unambiguous -- I've used program listings for this a great many times. But I don't generally favor their use, especially not in a proprietary language like Matlab. CRGreathouse (t | c) 04:51, 3 February 2010 (UTC)

Really? Which language do you use? Can we see some examples? Boris Tsirelson (talk) 07:16, 3 February 2010 (UTC)

I also think that sometimes programs make it easier to understand things. Recently I wanted to understand what the Floyd-Warshall algorithm does, and I just looked at Floyd–Warshall_algorithm#Pseudocode for 30 seconds and it was clear to me. Reading the text was too slow. But I also agree that there are many cases where I would prefer some math + English explanation instead of pseudocode, like for Strassen's algorithm. --Robin (talk) 13:48, 3 February 2010 (UTC)

If by "programs" you mean pseudocode then I have no objections. Pseudocode is not worse (nor better) than math formulas. I object to a code, just because it fits computers, not humans. Pseudocode fits humans. Well, not all humans; but the same holds for math formulas. But if a pseudocode is long and complicated, then it is as bad for WP as a long and complicated mathematical proof. Boris Tsirelson (talk) 15:29, 3 February 2010 (UTC)

Pseudocode is subject to the same restrictions as "normal" code - namely, it has to be formally rigorous. Thus, psuedocode can be just as complex as "real" code, and vice-versa converse/inverse what have you. I.e. a compiler / interpretor can be written for any "pseudo-code", thus making it no longer "psuedo-code"; thus, the only real difference between "pseudo-code" and "real code" is whether a compiler / interpreter has been written for it. Either can be as "fitting" or "un-fitting" for humans as you like, subject only to the restriction of formal rigour.

Whether we use pseudocode or real code comes down to a question of whether we invent our own formally rigourous language that no one is familiar with and a compiler hasn't been written for, or we use a pre-established one that many people are familiar with and can be compiled and tested readily. Kevin Baas^talk 15:49, 3 February 2010 (UTC)

If you require pseudocode to be formal then I object to it. But I believe it can be interpreted differently. I do not insist on the word "pseudocode". Boris Tsirelson (talk) 17:44, 3 February 2010 (UTC)

The whole point of it is to be formally rigorous. If that was not the goal, then a paragraph of plain english would work much better. As was pointed out above, a programmer like myself might come to an article, and read "bla bla bla bla", then get fed up and skip to the code/pseudocode and in 30 seconds be like "Oh, i get it." Now if the code wasn't formally rigorous, instead they'd be like "well that doesn't make any sense." or "now that's still rather ambiguous." If you want plain english then just use plain english. If you want to be precise then you better d@mn well be precise, otherwise you're just going to add confusion. Kevin Baas^talk 17:50, 3 February 2010 (UTC)

If we were going to be formally rigorous, we should use a well-established and widely understood formalism: a long-established - and preferably open-source - computer language would be one possibility, but Principia Mathematica would be better. But I don't see why we should; our sources aren't - they are rigorous enough that the details can be left to the reader. Septentrionalis PMAnderson 20:08, 3 February 2010 (UTC)

That's the great thing about pseudocode: It's formal enough to be like a programming language, and yet informal enough that no one has to study its syntax or construction. Just knowing English and any other programming language allows you to understand pseudocode. --Robin (talk) 20:20, 3 February 2010 (UTC)

Yes, this is my idea of pseudocode, different from that of Kevin Baas. Boris Tsirelson (talk) 20:52, 3 February 2010 (UTC)

That is actually the same as my idea. My point is that if "It's formal enough to be like a programming language" then it's formal enough to be compiled/interpreted by a computer program to something that can be processed by a computer. And if it isn't, well, then it's not "formal enough to be like a programming language". Kevin Baas^talk 17:32, 10 February 2010 (UTC)

I am fine with an implementation in a particularly suitable language, for example using a common array programming language where optimal, but only when pseudocode is first given. I am personally greatly in favor of pseudocode algorithms in general. In mathematics, sometimes the abstract terminology keeps you from realizing what those things could be. I didn't understand what a Fourier transform was supposed to be doing until pseudocode made "bins" into quantized data. To restate from the Simplex talk, I feel that using a particular implementation exclusively represents a POV, not to mention, as with the OP, I as a non-MATLAB programmer find MATLAB code incomprehensible. What I do understand I can't rely on, because what I fail to notice or understand is likely to completely change the logical outcome of the program. Using a proprietary language in particular induces an economic factor. Would you write an article that requires the reader to follow along with a textbook? No, because then to use the article they have to buy that textbook. LokiClock (talk) 14:58, 4 February 2010 (UTC)

I've put forward some ideas on this at WT:MSM#Source code and pseudocode to see if we can get something done about it.--JohnBlackburne^words_deeds 15:47, 10 February 2010 (UTC)

Superslow process

Could an interested and knowledgeable editor please take a look at Superslow process and Vladimir Miklyukov? The creator of both is User:SobakaKachalova, who happens to be Miklyukov's daughter.

She doesn't like the tags currently on Miklyukov's article, so she asked for and received a 3rd opinion. She didn't like that either (she said "it did not work since the editors do not have interests in mathematics"). She currently has a {{helpme}} tag on her talk page, and I think she could use a hand.

Just an FYI, and probably irrelevant, but it all smells fishy to me... WorldCat has no records of the cited ISBNs; Miklyukov's last book (self-published in 2008 through Xlibris) is in no libraries (per OCLC 290444522 and OCLC 290444525); and the biographical references are to sources like Marquis Who's Who (which is not a reliable source).

Thanks! Dori ❦ (Talk ❖ Contribs ❖ Review) ❦ 00:16, 9 February 2010 (UTC)

Miklyukov appears, at first blush, to be notable -- though of course negative findings on the books might change my opinion. I have severe doubts as to the notability/appropriateness of Superslow process, though. In any case both have severe format/grammar/cleanup issues.

CRGreathouse (t | c) 21:19, 10 February 2010 (UTC)

Just so it doesn't look as if CRGreathouse is alone: I agree with these concerns. Hans Adler 01:51, 11 February 2010 (UTC)

Definition without meshes

I've just done some editing on Riemann–Stieltjes integral. I've tried to state the definition in a way that does not mention "meshes" of partitions, since I take the Riemann–Stieltjes integral to be a limit of a net. Here's how the "Definition" section now reads:

The Riemann–Stieltjes integral of a real-valued function f of a real variable with respect to a real function g is denoted by

$\int _{a}^{b}f(x)\,dg(x)$

and defined to be the limit, as the partition

$P=\{a=x_{0}<x_{1}<\cdots <x_{n}=b\}$

of the interval [a, b] becomes finer, of the approximating sum

$S(P,f,g)=\sum _{i=0}^{n-1}f(c_{i})(g(x_{i+1})-g(x_{i}))$

where c_i is in the i-th subinterval [x_i, x_i+1]. The two functions f and g are respectively called the integrand and the integrator.

The "limit" A (the value of the Riemann–Stieltjes integral) is a number such that for every ε > 0 there exists a partition P_ε such that for every partition P that refines the partition P_ε (i.e. P_ε ⊆ P), and for every choice of points c_i in [x_i, x_i+1],

$|S(P,f,g)-A|<\varepsilon .\,$

So improve it if you can. Michael Hardy (talk) 17:34, 9 February 2010 (UTC)

Sorry Michael, I reverted your edit. Indeed, the classical definition of the RS integral does use meshes rather than refinements. This is actually not equivalent to the latter generalized definition (a generalization usually attributed to Pollard, but often with Moore and Smith's name attached to it as well because of the connection with nets). McShane has an article that addresses exactly this point about the two different integrals, quite lucidly if I recall. The other references in the article also address this point, especially that by Hildebrant. Sławomir Biały (talk) 18:03, 10 February 2010 (UTC)

Gaussian minus exponential distribution

Gaussian minus exponential distribution needs work. In particular, it's an orphan: other pages should link to it. Michael Hardy (talk) 03:14, 10 February 2010 (UTC)

I turned up no hits in Google books and 7 in Google web, most of which point to the Wikipedia article. My conclusion is the subject isn't notable and the only work that should be done is an AfD.--RDBury (talk) 16:15, 10 February 2010 (UTC)

This article by Carr & Madan from the Journal of Computational Finance, using the term Gauss minus exponential, and appears to be the main source. This item, apparently a master's thesis at Imperial College in London, uses the term Gaussian minus Exponential and cites the paper by Carr & Madan. "Normal plus exponential" appears more frequently and may be mathematically the same thing; apparently it's applied in biochemistry and in psychology. Michael Hardy (talk) 17:19, 10 February 2010 (UTC)

Zeno's paradoxes

See Wikipedia:Arbitration/Requests/Case#Zeno.27s_paradoxes, which is entirely a contents issue as far as I can tell. Pcap ping 16:30, 11 February 2010 (UTC)

Quasipositive function

This article has been proposed for deletion. If you have knowledge of the subject kindly take a look to see if it is worth salvaging. -Arb. (talk) 23:34, 12 February 2010 (UTC)

I speedied it - "definition" didn't define anything. Charles Matthews (talk) 08:51, 13 February 2010 (UTC)

Positive definiteness - disambig?

I had marked Positive definiteness as a disambiguation page, but it was reverted. Could someone else look at that? — Carl (CBM · talk) 19:30, 13 February 2010 (UTC)

I think I see the reverting user's point of view. It might be nice to have a page about the concept of positive definiteness itself, and then link to its usage in mathematics. As far as I understand, the usage of the phrase conveys a similar meaning in all applications. Alternately, the disambiguation page could just explain the idea of positive definiteness in 2 lines, and then link to the various uses in mathematics. --Robin (talk) 20:05, 13 February 2010 (UTC)

The article doesn't really work as anything but a dab page. Generally, though I know someone will think of an exception, adjectives and abstract nouns don't make good subjects for articles.--RDBury (talk) 21:36, 13 February 2010 (UTC)

Movable cellular automaton

As Michael Hardy would say, this article is a mess. But before asking people to get to work on it I would note that notability is marginal. I did not turn up any secondary sources for the subject but I did turn up a plethora of primary sources from a variety of disciplines so maybe the notability criteria could be stretched to include this. The article itself seems to be the brainchild of a something called "MCA lab", presumably pictured at the bottom of the article. There is a huge amount of material in the article but with no references given so impossible to say how much of the material is original research. At the least, there are huge COI issues with the authors writing about their own work. If there is salvageable material here then it should probably be saved and turned to the kernel for a better article, but if a complete rewrite is needed then I'd say it would be better to delete for now and recreate it if/when secondary sources appear.--RDBury (talk) 03:31, 14 February 2010 (UTC)

Note: The article seems to have been developed concurrently in both English and Russian, click the link next to the article to see the Russian version.--RDBury (talk) 03:41, 14 February 2010 (UTC)

Help:Displaying a formula

Help:Displaying a formula seems to have a lot of focus on how WP works technically and doesn't seem to be too clear. These details are probably unecessary ( or could be put in a technical paragraph at the end ) and seem to be a left oer of a design spec rather than a help page. I have no idea how much of the information is relevant or useful, so could do with some pointers on what to do with this page, many thanks --Lee∴V (talk • contribs) 15:32, 10 February 2010 (UTC) (Wikipedia:Help Project)

If you're talking about the TeX vs HTML section then I think it's needed. The current TeX implementation is a bit of a kludge since it sometimes renders a formula as an image and sometimes as html and these can appear very different on a browser. Unfortunately, editors need to know about what's going on to be able to control the appearance of the formulas they type in. Someday, though I don't think it's going to happen soon, the wiki TeX renderer will be smart enough to match the size of a formula to the surrounding text and these technical details won't be necessary, but until then editors will need to know the difference between x and $x\,.$--RDBury (talk) 16:02, 10 February 2010 (UTC)

Hmmm, maybe we should put your words as an intro to the technical bit, they make more sense than the whoe paragraph! keep fingers crossed for advancements - I've seen hints that WYSIWYG editing is getting closer so miracles can happen! --Lee∴V (talk • contribs) 19:26, 10 February 2010 (UTC)

Help:Displaying a formula is very relevant and useful for editors of Wikipedia's mathematics and science articles. It is the essential guide to Wiki's implementation of LaTEX, and a "must read" if you are editing any Wikipedia article containing mathematical expressions. I use it for reference at least once a week. Gandalf61 (talk) 16:14, 10 February 2010 (UTC)

Ah - I understand the page itself is useful, was just wondering about its presentation --Lee∴V (talk • contribs) 19:26, 10 February 2010 (UTC)

I use Help:Displaying a formula frequently when I forget how to generate a particular symbol. I scan it for the symbol and look at the sequence of characters which generate it. Please do not remove any such information from the article. Thank you. JRSpriggs (talk) 09:26, 12 February 2010 (UTC)

Don't worry - I have no plans to remove it, just checking bits of it weren't a leftover from being transfered from Mediawiki help... Lee∴V (talk • contribs) 02:18, 15 February 2010 (UTC)

Polynomially reflexive space

Dear Wikimathematicians, the above article is being considered for deletion. 131.211.113.1 (talk) 22:46, 14 February 2010 (UTC)

Recent changes to Interpolation, Lagrange polynomial, Polynomial interpolation

Can someone please have a look at these articles and the discussion here. I removed some changes which seemed totally out of place but User:MathFacts has just reinstated them with slight adjustments in position. It's not particularly my area of expertise so I don't recognise the formulae he's trying to insert, but they certainly don't belong in those articles in their current forms.--JohnBlackburne^words_deeds 18:58, 17 February 2010 (UTC)

I agree, they should be removed. One wonders why this editor is insistent on plastering the same content over multiple articles. I went ahead and removed them. Sławomir Biały (talk) 19:52, 17 February 2010 (UTC)

Dont you agree that interpolation formulas should be in articles about interpolation? Is it unnatural somewhat? Should not Lagrange interpolation formula be in article about Lagrange interpolation?--MathFacts (talk) 22:43, 17 February 2010 (UTC)

I would want to see a proper citation for those formulae showing people think they are worth writing about rather than just something you thought were useful and you worked out yourself. Dmcq (talk) 22:57, 17 February 2010 (UTC)

Not to mention the fact that there are already more typical formulas in the Lagrange interpolation article. Sławomir Biały (talk) 23:09, 17 February 2010 (UTC)

See my talk page.--MathFacts (talk) 23:57, 17 February 2010 (UTC)

Direct sum - another DAB outreach request

Hi all, I was wondering if we could get some (more) help from this project. I'm working on the Wikipedia:Disambiguation pages with links project, and one of the most-linked dabs is Direct sum. This used to be a redirect to Direct sum of modules, but in December it was converted into a disambig, and now it has over 100 links that need fixing. I'm sure most of these should be pointing to Direct sum of modules, but I don't feel qualified to make that call. Could someone give us some guidance? The list of links can be found here. Thanks! --JaGa^talk 09:30, 17 February 2010 (UTC)

I can take a look at it later today. One problem, though, is that some of these should really target articles that don't yet exist: e.g., the occurrence in Representation of a Lie group should target Direct sum of representations, and the occurrence in Reductive Lie algebra should target Direct sum of Lie algebras. RobHar (talk) 15:02, 17 February 2010 (UTC)

Let's change them to those redlinks, then, and add them to Wikipedia:Requested articles/Mathematics.

CRGreathouse (t | c) 16:43, 17 February 2010 (UTC)

The definition of the direct sum of two Lie algebras is given at direct sum of modules#Direct sum of algebras, which is where I've been linking to in that case. There's no real information there though. Algebraist 17:03, 17 February 2010 (UTC)

I would have preferred linking to Direct sum of Lie algebras, redirecting that to Direct sum of modules#Direct sum of algebras, and marking it with {{R to section}} and {{R with possibilities}}. CRGreathouse (t | c) 19:41, 17 February 2010 (UTC)

Looking at some of the articles that link to Direct sum, it looks to me like "Direct sum" should be an article, not a dab. For example, the first five articles listed here are all referring to general notions of the direct sum, not any specific direct sum (e.g. the article Limit (category theory) mentions that colimits generalize constructions such as coproducts and direct sums). I'd suggest turning "Direct sum" back into an article (there would of course still be many links to change). Thoughts? RobHar (talk) 17:54, 17 February 2010 (UTC)

The fact that the first few are all references to direct sum in a general sense is an artefact of my fixing effort: I retargetted the others, and I was working from the top. I think most of the incoming links are specifically about the case of vector spaces/modules/algebras. Still, I think there's probably enough material in the general concept for an article, which could also briefly cover any specific uses that don't yet have articles. Algebraist 18:59, 17 February 2010 (UTC)

I'm going to turn "direct sum" into an article, approximately following the template of Direct product, and go through the links. RobHar (talk)

I also think "direct sum" needs its own article. Direct sums are coproducts in abelian (or additive or preadditive) categories and this is a framework into which specific examples fit. Geometry guy 20:57, 17 February 2010 (UTC)

Alright, I got through all the links and disambiguated them. The article direct sum still needs some work though. RobHar (talk) 04:06, 18 February 2010 (UTC)

Thanks so much for the help, everyone. It is greatly appreciated. --JaGa^talk 09:05, 18 February 2010 (UTC)

\mathrm is not the same as \text (nor is \mbox)

In Baker's map, I found this:

$S_{\mathrm {baker-folded} }(x,y)={\begin{cases}(2x,y/2)&{\mbox{for }}0\leq x<{\frac {1}{2}}\\(2-2x,1-y/2)&{\mbox{for }}{\frac {1}{2}}\leq x<1\end{cases}}$

I changed it to this:

$S_{\text{baker-folded}}(x,y)={\begin{cases}(2x,y/2)&{\text{for }}0\leq x<{\frac {1}{2}}\\(2-2x,1-y/2)&{\text{for }}{\frac {1}{2}}\leq x<1\end{cases}}$

The first uses \mathrm{baker-folded}; the second uses \text{baker-folded}. When \mathrm is used, the hyphen becomes a minus sign; when \text is used, it remains a hyphen. The first uses \mbox{for }; the second uses \text{for }. In some contexts, those look much more different from each other than in the example above. For example, contrast \min_\mbox{abcd} with \min_\text{abcd}:

${\begin{aligned}\min _{\mbox{abcd}}\\[8pt]\min _{\text{abcd}}\end{aligned}}$

The purpose of \mbox is to prevent line-breaks when TeX is used in the usual way as opposed to the way it's used within Wikipedia. It shouldn't be used as a substitute for \text. Michael Hardy (talk) 15:57, 18 February 2010 (UTC)

Indeed. I guess the problem is that \text comes from AMSLaTeX (amsmath) rather than base LaTeX, therefore some people are not familiar with it.—Emil J. 16:03, 18 February 2010 (UTC)

I don't think \text was always supported by Wikipedia's implementation of TeX (correct me if I'm wrong). So there might be some legacy \mathrms lying around. Sławomir Biały (talk) 00:08, 19 February 2010 (UTC)

I seem to remember it that way too. But I'm not sure all of them are from the time when we didn't have \text. Maybe when we got \text, some people never found out. Michael Hardy (talk) 02:35, 19 February 2010 (UTC)

ANI notice... about this whole WikiProject

Some sort of group sanctions are requested. See Wikipedia:ANI#Harassment. Pcap ping 01:37, 17 February 2010 (UTC)

Despite the request for action against this WikiProject (!), we're really not a party to this discussion. The exception is User:Hans Adler who seems to be accused of sockpuppetry and harassment; I will notify him on his Talk page. CRGreathouse (t | c) 01:57, 17 February 2010 (UTC)

Well, ANI etiquette requires a notification. Since he asked for a 24hr block of all members of this project, it seemed appropriate to post here. The request was dismissed as silly, so this should probably just be moved to archives to lower the drama. Pcap ping 04:04, 17 February 2010 (UTC)

I was about to post a similar note asking if anyone had some constructive suggestions on ways to move things forward. -- Banjeboi 10:30, 17 February 2010 (UTC)

Last time this was discussed here, there was an agreement to do something, but we couldn't agree what exactly. There was split opinion between a RfC/U, formal mediation, or more informal mediation by User:Charles Matthews. Eventually, nothing happened. Pcap ping 23:40, 17 February 2010 (UTC)

An ANI notice on the whole project! I guess it shows some imagination. Can I suggest also he use WP:BLP to stop references to his previous excursions being brought up, and WP:COI and WP:POV be used to prevent anyone with a maths degree editing any maths articles ;-) Dmcq (talk) 23:53, 17 February 2010 (UTC)

As long as we understand that it is not POV when people from different academic disciples contribute to articles. I am wrongly accused by members of this project of POV all the time --for legitimate subject matter. So I am glad to see that you agree with me that interdisciplinary coverage is not POV. Now lets see if the members respect that.Greg Bard (talk) 19:13, 18 February 2010 (UTC)

Absolutely everyone agrees that well informed interdisciplinary coverage is a good thing. But it is impossible to see as serious the suggestion that each of the members of this project be blocked! It simply looks like disruption and grandstanding. Paul August ☎ 13:38, 19 February 2010 (UTC)

Ordinarily I would agree with you. I am pretty well known by my friends as very anti-corporatism in general. This is to say that I am against holding groups to have rights or privileges beyond individuals. I am against corporate personhood, in favor of abolishing the US Senate, I Decline to state, rather than support a political party, etcetera, etcetera, etcetera. Only this group, and the behavior of its members has risen to a level to where I would scrap a good principle, in order to deal with the pragmatic reality. I think if there were consequences for the high drama it would end. In any case, the members shouldn't concern themselves with the possibility of sanctions, but rather that they are being brought up. It reflects on the group. I don't know if anyone has a sense of this at all. But as a matter of civility, decency, leadership, etcetera, you should. Greg Bard (talk) 23:56, 20 February 2010 (UTC)

Well, at least you know your principles and stick to them, unless something this important comes up. CRGreathouse (t | c) 00:30, 21 February 2010 (UTC)

Absolutely! At some point you may have to spank the child, and not be held hostage by the abusers. I do, in fact, believe that collaborating civilly is very important, more so than your groups' play time.Greg Bard (talk) 01:59, 21 February 2010 (UTC)

Because you are the parent and WikiProject Mathematics is your misbehaving child? And it needs to be punished for the action of an IP user not apparently related in any way to this project?

Seriously, Greg... drop the stick and back slowly away from the horse carcass.

CRGreathouse (t | c) 02:30, 21 February 2010 (UTC)

WP:BEANS. Pcap ping 18:56, 18 February 2010 (UTC)

It's been archived to Wikipedia:Administrators' noticeboard/IncidentArchive597#Harassment. I think we can let the matter drop now. CRGreathouse (t | c) 15:43, 19 February 2010 (UTC)

If you've been following it you might like this video of cat herding. Shows it's possible :) Dmcq (talk) 17:17, 19 February 2010 (UTC)

Could someone check my changes to Homogeneous differential equation, please?

I've presented the whole intro to the homogeneous differential equation article using a more general formulation that makes the link to homogeneous functions clearer, rather than just taking the special case of f(x,y) = F(y/x), which only covers the case of homogeneous differential equations of degree 0.

I hope that this is both more elegant and more general than the previous text, and provides a better lead-in to the second example lower down the article; in particular it makes clear in advance what "degree" means in this context, which is otherwise just thrown in without explanation.

However, my maths education was a very long time ago: can people here please check my changes? -- The Anome (talk) 03:52, 17 February 2010 (UTC)

The original definition seems be more in line with that given in MathWorld which, sad to say, seems to be the only valid reference. Do you have a reference for the definition you added?--RDBury (talk) 01:22, 18 February 2010 (UTC)

No, just vivid memories of long-past math tutorials. A quick Googling finds this Cliff's Notes page, which appears compatible with the new treatment, albeit phrased in termos of differentials. -- The Anome (talk) 02:20, 19 February 2010 (UTC)

Actually, that reference is more compatible with the old treatment. (For them, M and N must have the same degree, so F=M/N must have degree zero.) But, at any rate, I have added Olver as a reference to the article which supports the new treatment. While I trust that he knows his business quite well, it would be better to have a more authoritative source on differential equations as such. Sławomir Biały (talk) 02:31, 19 February 2010 (UTC)

This is puzzling. There seem to be two different definitions in play; the first being the more general one, and the second the special case where degree=0. Most references discuss the second case, and only a few discuss the first, generally in the context of showing the standard method of solution by change of variables. However, since the degree=0 case is a subset of the general case, references supporting the special case don't invalidate the general case. I'll havbe to do some more searching in the print literature. -- The Anome (talk) 13:47, 20 February 2010 (UTC)

In the meantime, I've wound the definition back to the previous, more restrictive case, and removed the whole second half of the article, which implicitly used the second, more general definition. -- The Anome (talk) 14:21, 20 February 2010 (UTC)

That seems like overkill to me: I'm happy with either version (see my comment at the very end of this thread). But I agree with RDBury's original sentiment that more solid references are needed either way it goes. Sławomir Biały (talk) 14:41, 20 February 2010 (UTC)

I think the new definition is wrong (well, at any rate, not what I would call a homogeneous differential equation): dx and dy should also carry weight one, in which case the old definition is correct, the right-hand side must have homogeneity zero. It's probably more intuitive to think of it in differential form as $f(x,y)dx+g(x,y)dy=0$ with f, g homogeneous functions. Sławomir Biały (talk) 01:54, 18 February 2010 (UTC)

I just looked this up, and apparently I stand corrected. The more general definition is actually classically known as homogeneous. I don't have a very authoritative source, but Olver's Equivalence, Invariants, and Symmetry does have a discussion of homogeneous equations from this point of view. I will add it to the article. Sławomir Biały (talk) 13:40, 18 February 2010 (UTC)

List of Italian mathematicians

Hi. Plenty of missing articles to start! See Italian wikipedia biography equivalent... ‡ Himalayan ‡ ^ΨMonastery 18:04, 18 February 2010 (UTC)

Could you replace "(matematico)"? Charles Matthews (talk) 13:58, 20 February 2010 (UTC)

Naperian logarithm article

Is Napierian logarithm accurate? Is it a joke? Based on the current content, I would believe either one. — Carl (CBM · talk) 04:12, 19 February 2010 (UTC)

I added some references. It appears to check out. —David Eppstein (talk) 05:02, 19 February 2010 (UTC)

The DNB article on Napier explains the history, namely that Henry Briggs of Gresham College saw the advantage of the change to a more standard linear function of the Napierian logarithm not long after the first publication. The two articles complement each other. Charles Matthews (talk) 07:51, 19 February 2010 (UTC)

Thanks. My concern was with the 10^7 stuff, which seems arcane even for historical mathematics, and I didn't see a reference for that right away. I'm glad the article was not actually a joke. — Carl (CBM · talk) 11:47, 19 February 2010 (UTC)

FWIW, the base 10 log is sometimes called Briggsian logarithm for contrast. Pcap ping 08:40, 19 February 2010 (UTC)

If you have a look at Prosthaphaeresis you'll wonder why someone didn't try inventing Napierian logs earlier. Or for something even wierder wikt:logarithmancy which used Napierian logarithms for divination though no-one now know knows how. Dmcq (talk) 13:33, 19 February 2010 (UTC)

My thinking is this should really be part of an article called Mirifici Logarithmorum Canonis Constructio.--RDBury (talk) 18:22, 19 February 2010 (UTC)

I'm not totally sure that's what I would type into a search box to try and find it! Dmcq (talk) 20:21, 19 February 2010 (UTC)

That's why we have redirects. But if the subject is really about logs as they appeared in their original work then the article should be about the original work, especially since we don't already have an article and the subject is certainly notable.--RDBury (talk) 18:10, 20 February 2010 (UTC)

I would leave it here. The modern development, sometimes called Napierian, has a perfectly good home under natural logarithm, leaving this title free. On the other hand, an article on the book should be focused on the book itself and the secondary scholarship directly on it. No, it's not a joke - somewhere there should be an explanation that Napier multiplied through by 10^7 because the modern system of decimal places was not yet established. Septentrionalis PMAnderson 20:06, 21 February 2010 (UTC)

Mathematosis... again

In its present form, it is very difficult to see how Wikipedia:WikiProject Countering systemic bias/Mathematosis is constructive. It is substantially a recreation of the deleted essay Wikipedia:Mathematosis. Sławomir Biały (talk) 12:28, 20 February 2010 (UTC)

Could, indeed should be copyedited to bring it into line with Quine's view of "systemic bias" effects. It ought to be the case that increased coverage of philosophical logic does not diminish what is written here in mathematics and mathematical logic. Charles Matthews (talk) 12:48, 20 February 2010 (UTC)

It looks like he might have started with something which would have been fairly reasonable about countering too much of a mathematical bias in logic and philosophy articles but has recently been renamed and gone to all out attack on mathematicians. If the page was renamed back to something more appropriate and the contents reverted to more reflect the original concerns it could serve some useful function I guess. At the moment it is becoming more nasty silliness like all the other stuff on this that had to be removed earlier. Dmcq (talk) 13:16, 20 February 2010 (UTC)

It's an essay, not a page in userspace. I signed up with the systemic bias WikiProject ages ago, and I'm going to treat this as {{sofixit}}. Given the question posed (does mathematical logic as addressed by mathematicians imply a systemic bias in the treatment of logic, a subject that existed for two millennia before the 1930s?), there is a reasonable discussion in there trying to get out. Charles Matthews (talk) 13:54, 20 February 2010 (UTC)

I would rewrite the lead to remove the strange emphasis on "mathematosis". At least as the term is described there, it refers to a (real or imagined) chauvinism of certain editors of mathematics, rather than a systemic bias issue. I would also change the title of the article back to the more obvious choice Wikipedia:WikiProject Countering systemic bias/Mathematics. Other than that, the essay is already looking much improved. Thanks! Sławomir Biały (talk) 15:01, 20 February 2010 (UTC)

If this is improved then how bad was it before? Maybe I'm showing my bias but it seems like most of the issues brought up in the essay are just silly. Is it our fault that WP Math gets more traffic than WP Philosophy? Are we supposed to merge Field (mathematics) with Field (agriculture)? It seems to me that the previous deletion discussion applies just as well to this version.--RDBury (talk) 18:37, 20 February 2010 (UTC)

I agree that the page is still horrible and doesn't belong in project space in this form. It contains some reasonable ideas: E.g. a lot of people would be interested in the philosophical side of certain concepts, but we only present the mathematical side. I guess this is due in part to the relative weight of mathematicians in this project, and in part to a pro-mathematical bias not just among mathematicians but also among those philosophers who deal with logic. Let's not forget that many great early logicians who we now see as mathematical logicians started as philosophers.

But there is still too much Gregbard idiosyncracy and nonsense on this page, in particular the underlying assumption that just because mathematicians use a word that has also been used by a philosopher who Gregbard has been reading recently, that philosopher's definition of the word must have more than a marginal connection to the mathematical term of the same name. And of course the silly reference to "mathematosis". Of course, if we assume that mathematicians talking about "classes" in set theory really mean some philosophical concept, whose philosophically relevant aspects they choose to ignore, preferring instead to make some silly superficial games that entirely miss the point, then the accusation of "mathematosis" makes some sense. (Other example: [2].) But in my opinion it is this kind of assumption that misses the point. The fact that Gregbard's arguments only make sense as arguments from ignorance probably explains why he is not getting much support from philosophers in his quixotic struggle. Hans Adler 19:49, 20 February 2010 (UTC)

As I say, the page should be fixed up: it's a good exercise in writing for the opponent. Charles Matthews (talk) 08:01, 21 February 2010 (UTC)

I don't see how this makes sense. I doubt there are many here who see interdisciplinarity as an opponent. And writing from the POV of a conspiracy theory is also not an example of writing for the opponent. Hans Adler 20:07, 21 February 2010 (UTC)

Mischief

A newly created account User:Basemaze has been engaged in vandalizing displayed math equations with mischievous edit summaries ("fixed an error", etc). Arcfrk (talk) 18:54, 20 February 2010 (UTC)

Reverted and warned. (It's not just math articles.) The appropriate venue is probably WP:AIV, rather than here. If he continues, report it there. — Arthur Rubin (talk) 19:24, 20 February 2010 (UTC)

I warned, because the edits were in a half hour period over 4 hours ago. If the edits were still occurring, I would have blocked. — Arthur Rubin (talk) 19:53, 20 February 2010 (UTC)

It appears that I should have just blocked. He's now reported he has no interest in improving Wikipedia. Oh, well, we still don't block on request. — Arthur Rubin (talk) 08:33, 21 February 2010 (UTC)

AfD of possible interest

It has been suggested to inform this WikiProject of Wikipedia:Articles for deletion/Texvc. I am the nominator for that AfD, by the way. Pcap ping 16:10, 21 February 2010 (UTC)

Thread of possible interest

See WP:ANI#User:Likebox deceptively sourced infraparticle. It's about some physics articles but raises issues for math as well and some of the concerned parties have also edited math articles. As near as I can tell the short story is: someone tagged [citation needed] on some physics articles, Likebox (talk · contribs) and Count Iblis (talk · contribs) felt that the tag was unwarranted as the facts in question were simple calculations, and in response these two users went on a spree of replacing fact tags by deliberately fake references and boasted about it on Jimbo's talk page. But there's a lot of chatter in the thread so it's hard to tell for sure whether that's an accurate description of both sides of the story, it's not clear whether "deliberately fake" means that it doesn't source the calculation at all or merely that it is off-topic for the primary subject of the article in question, and I have not formulated an opinion over whether the citation needed tags really were appropriate.

Anyway, the reason I'm bringing this to the project's attention is that a lot of our articles contain things that really are simple calculations that should not need a source according to WP:OR#Routine calculations and WP:Scientific citation guidelines#Examples, derivations and restatements. It would be a shame if someone's misbehavior led to an overreaction in the other direction. —David Eppstein (talk) 02:25, 22 February 2010 (UTC)

It seems that the issue at the infraparticle article was a mathematically-inclined explanation for which some editors wanted citations for individual steps. Likebox added some citations for steps, but complained that these didn't really address the point of the article, just the individual steps. Unfortunately, I haven't seen anyone actually analyze whether Likebox's edits were accurate, and so it is hard to tell what's really going on.

However, there are two deeper issues with the infraparticle article that make me think it isn't reflective of the problems we encounter with math articles.

1. Apparently the topic is not discussed in textbooks, only in journal articles. Most mathematics topics here are discussed in textbooks or in a significant number of journal articles.
2. Mathematics texts and journals are very likely to have complete proofs for facts they claim, or give references to complete proofs. This makes it easy for us to give citations for proofs and for explanations. Research articles in other fields do not always include proofs for derivations, or only include sketches. This can make it more difficult for them to clearly source things in wikipedia articles, since the literature is not particularly helpful.

— Carl (CBM · talk) 02:43, 22 February 2010 (UTC)

Methods of contour integration

As a side note: the discussion about infraparticles somehow led to Methods of contour integration being tagged as POV. Probably more people should watch that article for a little while. — Carl (CBM · talk) 02:50, 22 February 2010 (UTC)

Looks like Headbomb needs a little defusing. Pcap ping 12:41, 22 February 2010 (UTC)

Source code discussion

Continuing from the earlier, archived discussion, the thread Wikipedia talk:Manual of Style (mathematics)#Source code and pseudocode has been discussed, and a consensus needs to be reached. LokiClock (talk) 00:02, 23 February 2010 (UTC)

Paravector

Not to disparage the original author, but I've just come across this article which in my most humble opinion, is a little suspicious. I am nowhere near competent enough in pure mathematics to be able to tell whether or not it's a load of hooey or otherwise lacking in rigor, but something stands out about it. One thing that drew my attention but which I'm trying not to be prejudiced by is the personal promotion in the introduction. At the very least, it's quite hard to follow. Could this be checked out by an expert? Sojourner001 (talk) 18:24, 23 February 2010 (UTC)

I'm not claiming to be an expert, but the subject does seem to be notable.--RDBury (talk) 19:40, 23 February 2010 (UTC)

Clifford algebras are notable; but this seems to be somebody's private nomenclature. Septentrionalis PMAnderson 19:51, 23 February 2010 (UTC)

I wasn't questioning its notability, more its truthfulness. Citing sources and demonstrating its utility in deriving a proof surely makes it notable if the proof is correct and the sources verified. Sojourner001 (talk) 21:29, 23 February 2010 (UTC)

Geometric algebra always seems to me like a little bit a walled garden. But it is fervently defended by its adherents—who are able to produce sources that are apparently considered reliable within that community. Sławomir Biały (talk) 20:23, 23 February 2010 (UTC)

FWIW, the references cited at paravector are all Physics, not Math books. Pcap ping 21:22, 23 February 2010 (UTC)

Movable cellular automaton followup

The Movable cellular automaton article I brought up previously was PRODed. The article has issues as I mentioned above but I didn't think they were clear cut enough for the article to be deleted without a discussion, so I changed the Prod to an AfD. The deletion discussion is at Wikipedia:Articles for deletion/Movable cellular automaton.--RDBury (talk) 05:17, 24 February 2010 (UTC)

A logical prison

Bocardo Prison suffers from poor notation, caused by a traditional example being put together with an existing Venn diagram. Help would be appreciated. Charles Matthews (talk) 12:50, 20 February 2010 (UTC)

It looks like as it stands there is more in the article about the syllogism than the prison. Having Venn diagrams for the classical syllogisms seems appropriate but they would go in the Syllogism article rather than this one.--RDBury (talk) 18:52, 20 February 2010 (UTC)

Carp on - I created the article yesterday. And asked for help here. Why are you such a bloody negative misery to have around? There is plenty more history that could be added. And it is in fact perfectly reasonable to exemplify the syllogism, considering that it was proverbial for difficulty. Charles Matthews (talk) 07:56, 21 February 2010 (UTC)

I think you misunderstood me. All I'm saying is if you want to add material about the syllogism then add it to syllogism article, or create a new article on Bocardo (syllogism). It's good to tell people what Bocardo is and have a link to it, but detailed examples and Venn diagrams belong somewhere where people who are interested will be more likely to find it. As for being a negative misery, you're right, sometimes I am one; so sue me. But I don't make comments here to be liked. I made what I think is a legitimate criticism of the article, with which you can either agree or disagree. And your right in that if I couldn't find anything negative to say then I probably wouldn't say anything. But the point of this forum is to improve math articles, not praise each other's work.--RDBury (talk) 18:46, 21 February 2010 (UTC)

Well, water off a duck's back to me, but if you want to review articles, try FA candidates, not stubs that have been on the site for only a few hours that are brought here for help. If I were a newbie, would you have been so negative? Apparently so. And your evaluation of the project's aims seems to leave out human factors, which is a blunder. As well as the irony of being told that the logic has to be segregated in logic articles, with no scope for outreach, just below the thread above. Show me something else where a social science topic gets named after a logic topic - you underestimate our readers with your people who are interested, when the idea would be to get people interested in one valid pattern reasoning out of 15, not to require them to browse the other 14. Charles Matthews (talk) 12:34, 22 February 2010 (UTC)

I'm not sure how to respond without making this argument worse than it already is. I didn't say take the logic part out entirely or you can't include anything about logic in a non-logic article, but the beauty of having links is you can point out a connection to another subject and the reader can get more information with a single click. But again, if you disagree then just ignore me. As for rest, this thread seems to have turned into a personal critique of me and my comments, and as much as I would like go on being the subject of the conversation I'm sure everyone else in this forum has had enough by now.--RDBury (talk) 23:00, 22 February 2010 (UTC)

Have to agree with RDBury here. The appropriate way to present this unrelated material would be to simply state "the prison was named after a term used in the philosophy of logic..." and link to a further explanation in the relevant article. I can't see how this has become an argument. It's certainly easier to intercept articles as they're created and make sure they prosper, than let them go unnoticed.Sojourner001 (talk) 21:05, 24 February 2010 (UTC)

C-class?

Sorry if this has been discussed earlier, but should WikipRoject Math perhaps introduce a C-class article rating for math articles? Quite a few other projects seem to have introduces a C-class rating. It does seem that there is a fairly substantial difference between start and B classes, so having something in between might not be a bad thing. Nsk92 (talk) 14:02, 23 February 2010 (UTC)

Actually it has been raised before but don't feel bad because it probably needed to be raised again. The other issue is we've got this weird B+ rating that no one else uses. The problem is that everyone seems to be split about evenly between about four ways of dealing with the situation, including the camp that thinks everything is fine as is. Really it should be discussed at Wikipedia talk:WikiProject Mathematics/Wikipedia 1.0 since the WP 1.0 page is where the ratings are defined.--RDBury (talk) 17:59, 23 February 2010 (UTC)

I remember a while ago there was a vote on Wikipedia:Version_1.0_Editorial_Team or some related project page on whether to introduce a new class and if so, where and what to call it. The consensus was to introduce the "C" class, as you can see by the chart. Though if i recall correctly it was up to the individual projects to adopt this class. In any case, while I see how the B+ class can be helpful, the "C" class fills a much larger gap. (and is actually recognized by the 1.0 project, whereas B+ is not)Kevin Baas^talk 18:09, 23 February 2010 (UTC)

I too think that it is better for us to be in line with most other wikiprojects, which by and large seem to have adapted a C rating. I also think that the gap between start and B classes is pretty big (considerably bigger than between B and B+) and I personally think that class B rating should be assigned rather conservatively. Another consideration here is that many people from other wikiprojects already assume (sort of by default) that we have a C class rating. I noticed this recently when one of the math articles I created was tagged as C-class[3] (I have since change the math rating there to "start"). This sort of thing is likely to happen more often as time progresses. Nsk92 (talk) 18:38, 23 February 2010 (UTC)

I added a proposal at at Wikipedia talk:WikiProject Mathematics/Wikipedia 1.0 with links to and a summary of previous discussions. I really think it's better to keep the discussion on a single page because it's a lot of work to track down various threads from 50+ archive pages. There is no sense in rehashing old arguments just because they're buried somewhere.--RDBury (talk) 19:10, 23 February 2010 (UTC)

Wikipedia 1.0 is a foolish idea. The one thing Wikipedia has never been able to do is rate articles consistently and on zubstantive merit; it's very hard to do it, and a bunch of ad hoc committees will not be cosistent - even if they had fewer cranks than any WikiProcess accumulates. Any change of practice done to assist it should be opposed. Septentrionalis PMAnderson 06:00, 24 February 2010 (UTC)

To me Wikipedia 1.0 is just a label. The maths rating tags are a means by which people in this project can keep track of the progress of work on math articles and are for our own benefit. If some other project wants to use them too I'm not going to stop them.--RDBury (talk) 16:44, 24 February 2010 (UTC)

Then do we, looking only at our own progress, need a C tag? That's a sensible question, but I'm not sure of the answer. Septentrionalis PMAnderson 21:21, 24 February 2010 (UTC)

AfD of interest

Wikipedia:Articles for deletion/List of numerical analysis software. Pcap ping 22:30, 24 February 2010 (UTC)

Featured picture candidates

There are currently two math related pictures being discussed for featured pictures: File:Pythagoras-2a.gif and File:Penrose Tiling (Rhombi).svg. See Wikipedia:Featured picture candidates/File:Penrose Tiling (Rhombi).svg and Wikipedia:Featured picture candidates/File:Pythagoras-2a.gif for discussions.--RDBury (talk) 08:22, 26 February 2010 (UTC)

More possible hoaxes

Zbacnik conjecture was prodded as a hoax by someone else and I just prodded the related article Luce number. There seems to be a bump in the number of questionable new articles recently so perhaps some extra eyes on Wikipedia:WikiProject Mathematics/Current activity would be helpful.--RDBury (talk) 06:37, 27 February 2010 (UTC)