MathFacts

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Hello, MathFacts, and welcome to Wikipedia! Thank you for your contributions. I hope you like the place and decide to stay. Here are some pages that you might find helpful:

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I hope you enjoy editing here and being a Wikipedian! Please sign your messages on discussion pages using four tildes (~~~~); this will automatically insert your username and the date. If you need help, check out Wikipedia:Questions, ask me on my talk page, or ask your question on this page and then place {{helpme}} before the question. Again, welcome! -- Mentifisto 06:40, 30 March 2009 (UTC)

Indefinite product - references ?

Hi ! I notice you have created a new article List of indefinite products. Do you know of a reliable source that uses the term "indefinite product" in the sense that you have used in on this page ? If you do, perhaps you could add it as a reference to the page - for an example of how to add references to a Wikipedia article, see the references that I have added to List of indefinite sums. One or more references will help to show that this article conforms to our verifiability policy, and is not original research. Gandalf61 (talk) 15:00, 1 April 2009 (UTC)

It seems like a self-explanatory term to me. Michael Hardy (talk) 16:07, 2 April 2009 (UTC)

The Israel-Palestine battlefield

Hi, I notice that you've made your first sortie into editing an article to do with the Middle East conflict. I want to warn you that this is an area of Wikipedia where there is often a lot of conflict between editors with differing political views, some of whom break Wikipedia's behaviour guidelines and end up being suspended from editing. If you intend to devote significant time to this subject area, it is worth checking up on some of the conduct and editing rules linked through the welcome message you received. Wikipedia has stricter standards on how to behave towards other ediors than many places on the web and this can atch ot some newcomers. In general, the talk pages are a good place to raise any point which you think might be controversial, though you don't really have to do so until you get reverted. (See WP:BOLD, revert, discuss cyclefor a discussion of this point.)

It's also a good idea to make sure that you keep contributing to relatively uncontroversial areas, (mathematics being a good example,) even if you do start spending a lot of time in the battlefield areas. This can reduce any frustration that other people's behaviour may cause and also marks you out as someone who is here to help write a general encyclopaedia rather than just push your ownn political views.--Peter cohen (talk) 18:08, 24 April 2009 (UTC)

Faulhaber's formula

There wasn't actually a contradiction between the two articles you commented on. One of them takes B₁ to be −1/2 and the other +1/2, and that explains the difference. Please see my comment at talk:Faulhaber's formula. Michael Hardy (talk) 21:29, 24 April 2009 (UTC)

May 2009

Thank you for your contributions to Wikipedia. In the future, it is recommended that you use the preview button before you save; this helps you find any errors you have made, reduces edit conflicts, and prevents clogging up recent changes and the page history. Also, please use edit summaries, it's actually more important than you may realize. Other than that, you're doing great and your contributions are really helpful. :) Thank you. OlEnglish ^(Talk) 19:14, 15 May 2009 (UTC)

Prostitution in Russia

Prostitution in Rusia in illegal. It is NOT a crime under the Criminal Code (it has been removed from there) but it IS an offense according to the Administrative Code (as you said, like drinnking beer in public). According to the 2008 Human Rights Report: Russia [1] "The organization and operation of a prostitution business is a crime, while selling sexual services is a lesser criminal administrative offense. (see the sectuion Women from the report"). So, yes there is such thing as a "criminal administrative offense", that's how it's called.

The current version of the article says: "Prostitution in Russia is illegal. It is a criminal administrative offence [2] (like for example drinking beer in a public place or walking nude on the street), the maximum punishment is a fine up to 2000 rubles. However, organizing prostitution (eg. operating brothels or other forms of pimping) is punishable by a prison term."

So please stop reverting the article. It starts by saying "Prostitution is illegal in Russia", as it is (it is an administrative offense, so yes it is illegal- all the other sections about each country start by saying wheather prostitution is legal or not there); and then it explains that it is an administrartive offence punishable by a fine. So please stop reverting this article. —Preceding unsigned comment added by 86.121.8.3 (talk) 01:11, 22 May 2009 (UTC)

Of course US State department knows better than Russian law. You know, there is no such thing as 'criminal administrative offence' offence is either criminal or administrative.--MathFacts (talk) 09:42, 22 May 2009 (UTC)

Prostitution in Russia

This version of the aticle explains things in a very clear way:

Prostitution in Russia is illegal. It is an administrative offence (not a criminal offence) [3] (like for example drinking beer in a public place or walking nude on the street), the maximum punishment is a fine up to 2000 rubles. However, organizing prostitution (eg. operating brothels or other forms of pimping) is punishable by a prison term. —Preceding unsigned comment added by 86.121.10.251 (talk) 11:52, 22 May 2009 (UTC)

Even if it is not a criminal offense, it is an administrative offense, punishable by a fine, and this needs to be explained in the article. —Preceding unsigned comment added by 86.121.10.251 (talk) 11:55, 22 May 2009 (UTC)

Yes.--MathFacts (talk) 18:56, 22 May 2009 (UTC)

Prostitution in Russia

I reverted the text to your original edit from the 20th of May, it is better I believe (I explained this on the history page). So let's have it this way. OK?

That is what you wrote then: "Prostitution is an administrative, but not criminal offence in Russia (like for example drinking beer in a public place or walking nude on the street). The maximum punishment is a fine up to 2000 rubles; however, organizing prostitution is punishable by a prison term."

I reverted it to that. —Preceding unsigned comment added by 86.121.11.90 (talk) 20:24, 22 May 2009 (UTC)

Linear operators

Since much of modern mathematics is dedicated to the study of linear operators, I am trying (with others' help) to move as many articles from Category:Linear operators into subcategories as possible. You are invited to participate in the discussion at Category talk:Linear operators. Sławomir Biały (talk) 14:04, 9 June 2009 (UTC)

Now, regarding your query on my talk page, although there are obscure and seldom if ever used generalizations of the derivative that are nonlinear, the vast majority are linear operators. What is really quite telling is you vehement insistence that differintegral be in the Category:Linear operators, while you seem to have no interest at all in adding more standard fare such as Gradient, Curl (mathematics), Divergence, and so forth, to the category. In fact, per your objection, almost everything in Category:Generalizations of the derivative could be added to the parent category. This would be inappropriate I think. Sławomir Biały (talk) 14:46, 9 June 2009 (UTC)

Per my intent, linear operators in calculus is intended for the usual linear operators of the infinitesimal calculus. Thus differentiation (and its variants), integration, and so forth. This category also keeps the main category free of clutter. As for where to put rotation (mathematics), it is already in Category:Unitary operators. I'm not sure I would put it in Category:Linear operators in calculus at the risk of overpopulating that category. Perhaps Category:Linear operators in geometry would be more appropriate. Sławomir Biały (talk) 13:09, 10 June 2009 (UTC)

June 2009

Please do not replace Wikipedia pages with blank content, as you did to Vladimir Orlov. Blank pages are harmful to Wikipedia because they have a tendency to confuse readers. If it is a duplicate article, please redirect it to an appropriate existing page. If the page has been vandalized, please revert it to the last legitimate version. If you feel that the content of a page is inappropriate, please edit the page and replace it with appropriate content. If you believe there is no hope for the page, please see the deletion policy for how to proceed. ZooFari 06:32, 20 June 2009 (UTC)

The redirect in that page is completely irrelevant.--MathFacts (talk) 06:33, 20 June 2009 (UTC)

Derivatives and integrals of elementary functions in alternative calculi

You have created a new article, Derivatives and integrals of elementary functions in alternative calculi, which consists only of a table of mathematical expressions, without any other context. This does not seem to have any encylopedic use in its current form, so I've tentatively marked the article for deletion using the {{prod}} template. Please could you make clear the context of the table, and why it is relevant to the article title, and then remove the template so the article can be kept? -- The Anome (talk) 13:48, 15 August 2009 (UTC)

Thank you for nominating the article for deletion a minute after creation. Great work!--MathFacts (talk) 13:50, 15 August 2009 (UTC)

I tagged it thirty-eight minutes after its creation, and five minutes after your last edit to it; I had assumed you had stopped editing at that point. I'm pleased you are going to expand the article further; could you please add some context to the article, for instance to make clear what alternative calculi are going to be under consideration in the article? -- The Anome (talk) 13:59, 15 August 2009 (UTC)

I cannot make saves after adding each character.--MathFacts (talk) 14:00, 15 August 2009 (UTC)

Can you please write an intro paragraph for this table? At the moment, it is meaningless to those who do not already understand its context: an introductory paragraph would help point them in the direction of the resources they would need to be able to understand its content. -- The Anome (talk) 20:37, 15 August 2009 (UTC)

Orphaned non-free image (File:Rectothermal.jpg)

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File:DPRK JK stamp.jpg listed for deletion

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Recent changes to Interpolation, Lagrange polynomial, Polynomial interpolation

I just undid the changes you made to these articles as in each case they did not make sense. They just seemed to be insertions of formulae which may be correct but without explanation it's unclear what they are meant to represent or how they would be used. More importantly they were inserted in the articles in positions which made the articles much less clear: in Interpolation before even the basic properties of interpolation have been established, and in the other articles in the introduction or just after it. In all cases it's not clear that such complex formulae add to the articles. The only one I can see which they might be relevant to is Lagrange polynomial, but it already has a derivation and explanation of a similar formula, i.e. it's not obvious it needs another.--JohnBlackburne^words_deeds 16:36, 17 February 2010 (UTC)

Regarding your changes. In Interpolation I inserted the formulae just before the examples section. I think general formulae should precede examples. Dont you agree? Regarding what do they add, this is exactly the expression for the interpolation polynomials in the most understandable form. First is Newton interpolation formula, second is Lagrange interpolation formula and third is rational interpolation formula. I found that Newton interpolation formula redirects to finite difference which is not what this expression about so I placed in in polynomial interpolation. I think this article without expolicite expression of the formulae is not complete.--MathFacts (talk) 18:12, 17 February 2010 (UTC)

(copied your reply here - easier to reply in one place) - the problem is they just don't make sense. There's no explanation as to what the different terms represent, how they relate to the rest of the article, or how they would be used. It may be they belong somewhere but without at least a bit of context it's impossible to say. The problem is particularly severe in Interpolation which is written at a less expert level, but even in the other articles they at the moment are out of place and don't belong.--JohnBlackburne^words_deeds 18:53, 17 February 2010 (UTC)

I really do not unerstand what do you want. Maybe you do not understand the formolae because of binomial coefficients designated with un-traditional signs? Please be more specific.--MathFacts (talk) 22:40, 17 February 2010 (UTC)

I can't - they simply are not clear enough to make sense of. With proper explanations of the terms and symbols, appropriately wikilinked, of their use, so it's clear how they relate to the article I might see how they'd fit in, but as it is they seem to bear no relation to the articles you're trying to insert them in.

Do you have any references for them? If you can give a source, online or offline, it might be easier for me and other editors to see where you're getting them from and so see how they fit in.--JohnBlackburne^words_deeds 22:47, 17 February 2010 (UTC)

Rational interpolation formula is from here: [4]. Newton's and Lagrange formulae are rather trivial and common knowledge.--MathFacts (talk) 23:01, 17 February 2010 (UTC)

Can you point out the exact page and line that this change is based on as I can't see it. And it's certainly not 'trivial and common knowledge'.--JohnBlackburne^words_deeds 23:25, 17 February 2010 (UTC)

Cannot find exact citation right now, but take formula from here: [5]: [6]

If x_i = i (equal distance between poles) we can rewrite it using factorials:

$\,\left(\prod _{j=0}^{n}(x-j)\right)\sum _{k=0}^{n}{\frac {f(k)(-1)^{n-k}}{k!(n-k)!(x-k)}}$

$\,{\frac {\Gamma (x+1)}{\Gamma (x-n)}}\sum _{k=0}^{n}{\frac {f(k)(-1)^{n-k}}{k!(n-k)!(x-k)}}$

Further only technical simplifications.--MathFacts (talk) 23:41, 17 February 2010 (UTC)

If the formulae aren't given as you say then it's original research so not allowed.--JohnBlackburne^words_deeds 23:50, 17 February 2010 (UTC)

Oh, these are 6-th grade class transformations. I know very well whatt is allowed in Wikipedia.--MathFacts (talk) 23:52, 17 February 2010 (UTC)

6th grade (at least here) is 11 years old, while the above formula is something I only understand as I've a degree. But as you seem prepared to argue it, perhaps present your steps here. Show the formula you've started with from the source, the intermediate steps and the final result. You say it's trivial to do so it should not take much time.--JohnBlackburne^words_deeds 00:46, 18 February 2010 (UTC)

Starting from this[7]:

$L(x)=\,\left(\prod _{j=0}^{n}(x-x_{j})\right)\sum _{k=0}^{n}{\frac {f(k)}{\prod _{j=0,j\neq k}^{n}(x-x_{k})}}$

Now let $x_{i}=i$ (interpolation over equidistant points $x_{i}=0,1,2,...n$)

$L(x)=\,\left(\prod _{j=0}^{n}(x-j)\right)\sum _{k=0}^{n}{\frac {f(k)(-1)^{n-k}}{k!(n-k)!(x-k)}}$

First part can be rewritten with factorials (actually factorials should be regarded as their generalizations to reals):

$L(x)=\,{\frac {(x+1)!}{(x-n-1)!}}\sum _{k=0}^{n}{\frac {f(k)(-1)^{n-k}}{k!(n-k)!(x-k)}}$

or with binomials:

$L(x)=\,{\binom {x}{n+1}}(n+1)!\sum _{k=0}^{n}{\frac {f(k)(-1)^{n-k}}{k!(n-k)!(x-k)}}$

$L(x)=\,{\binom {x}{n+1}}\sum _{k=0}^{n}{\binom {n}{k}}{\frac {f(k)(-1)^{n-k}(n+1)}{(x-k)}}$

$L(x)=\,{\binom {x}{n}}\sum _{k=0}^{n}{\binom {n}{k}}{\frac {f(k)(-1)^{n-k}(x-n)}{(x-k)}}$

--MathFacts (talk) 01:14, 18 February 2010 (UTC)

I just reviewed the changed in Interpolation and in that case I have to agree with JohnBlackburne's reversions. The formulas that were added used notation that was not introduced in the article and were far too specific for survey-like nature of the article. This by no means an obscure subject and I don't see any reason for not sourcing any new material.--RDBury (talk) 03:35, 18 February 2010 (UTC)

A couple of things seem strange to me about this whole affair. First of all, MathFacts does not seem to have considered the question of why to include this special case of the interpolation formula, where the interpolation occurs at the integer points, when the article already has the general formula. The consensus appears to be that the special case adds nothing of value, even if it were completely rewritten into suitable encyclopedic content. Secondly, there is the issue of using unexplained and nonstandard notation for what are apparently supposed to be binomial coefficients, even when the rest of the article uses the more traditional $\scriptstyle {\binom {n}{k}}$ notation. Thirdly, apart from these issue, all (or nearly all) of the formulas in question also include a limit as "N" tends to infinity: [8], [9], [10]. I don't see these limits in any of the sources mentioned so far, and they smell highly of original research. Anyway they are wrong: these limits do not converge in general, even for analytic inputs, not to mention the fact that they do not belong in articles about polynomial interpolation. Sławomir Biały (talk) 13:16, 18 February 2010 (UTC)

Regarding equidistant formalas - Newton series which already exists in the respective article is anyway equidistant. Regarding other considerations I agree with you, I changed the notation to Western-style appearance and the infinity limit needs either note that it does not always converge(as done in Newton series) or should be substituted with finite number of poles.--MathFacts (talk) 13:29, 18 February 2010 (UTC)

No, what we need is a reference to wash the stink of original research off of this whole affair. A source should be given, along with a page number, that exactly agrees with the formulas that you propose to insert (no kindergarten-level manipulations, please). Sławomir Biały (talk) 13:45, 18 February 2010 (UTC)

Newton series formula already exists in Wikipedia, the two other formulas are the special cases of Lagrange interpolation and Barycentric interpolation formulas respectively when those applied to the equidistant poles. Just take those formulas and insert equidistant poles in them.--MathFacts (talk) 13:49, 18 February 2010 (UTC)

None of this addresses any of my original points. Sławomir Biały (talk) 14:11, 18 February 2010 (UTC)

May I also point to Runge's phenomenon which explains why people aren't particularly interested in exact polynomial interpolation, using equidistant spacing, and certainly not in going to the limit. Dmcq (talk) 15:26, 18 February 2010 (UTC)

This phenomenon is charactertistic of any polynomial interpolation, not only equidistant. The all three formulae in question converge when Newton series converges and the limit of all them is the same as in Newton series.--MathFacts (talk) 15:32, 18 February 2010 (UTC)

Please read Chebyshev nodes. Dmcq (talk) 17:06, 18 February 2010 (UTC)

I myself used barycentric interpolation in my work and it helped much. I experienced no Runge effect in my particular case.--MathFacts (talk) 19:45, 19 February 2010 (UTC)

Warning Wikipedia:Three revert rule

In case you are not aware of it Wikipedia has a policy called the [Wikipedia:Three revert rule|three revert rule]]. -- PBS (talk) 21:42, 21 May 2010 (UTC)

Revision to Sid Meier's Alien Crossfire and Sid Meier's Alpha Centauri articles

I noticed that you have revised either Sid Meier's Alpha Centauri or Sid Meier's Alien Crossfire.

I intend to revise those articles following the Wikipedia:WikiProject Video games/Article guidelines. There are more details on the discussion pages of those articles. I'd be interested in any comments you have. It would be best if your comments were on the discussion pages of the two articles.

Thank you.

Vyeh (talk) 11:32, 8 June 2010 (UTC)

Kalinin

I responded to your inquiry on Kalinin in-re the NKVD at his article's talk page, if you're interested. --Mrdie (talk) 01:25, 8 October 2010 (UTC)

Proto-Indo-European numerals

Hi! Could you clarify what "Meillet MSL XIV" means? Thanks! --ἀνυπόδητος (talk) 14:55, 22 November 2010 (UTC)

All-People's Government

Brezhnev announced the term to the 25th Congress of the Communist Party of the Soviet Union, the term was official. "All-People's Government" was another way of refering to collective leadership. The Soviets used this term however. --TIAYN (talk) 12:59, 14 December 2010 (UTC)