User talk:Jitse Niesen/Archive9

question

Hi Jitse,

Just wondering....in your opinion, do you think that the factorialplex function could compactify the space of zeros of the Riemann-Zeta function?

thanks, trvce

ps - its alright to delete the article if you want.

To be honest, I'm not sure what you mean with "compactify the space of zeros of the Riemann-Zeta function". I guess you're hoping that f(S) is a compact set, where f is the factorialplex function (or perhaps its inverse) and S is the set of zeros of the zeta function? I don't know, it depends exactly how you define the factorialplex of complex numbers (your definition only works for natural numbers). As you probably know, the image of a compact set under a continuous function is again a compact set. I think that the set of zeros is unbounded and hence not compact, so you need a discontinuous function in order to map it to a compact set. -- Jitse Niesen (talk) 05:57, 3 April 2007 (UTC)

Fisher's equation

I have replaced much of Fisher's equation. The previous contents seems to be taken from EqWorld which has nice references but wrong math. Please check original literature (not websites) in case you consider rv. Thanks. Also, maybe it should be merged with reaction-diffusion equations, which looks a bit sad. Jmath666 08:08, 1 April 2007 (UTC)

Thanks for your work. However, was there anything wrong with the previous version? I can't find a mistake (which admittedly doesn't mean much). Or do you mean that it was rather misleading in that it suggested that there is only one travelling wave solution?

As it happens, I did some work on reaction-diffusion equation yesterday. I agree that it looks sad (I hope to work a bit more on it), but I think it looked even sadder before. I'd be very happy with any help in bringing that page in a better state. It certainly needs a description of travelling waves.

Speaking about original literature, I've never read the book by Fisher that you mention. Does this contain the equation? In my experience, the usual reference is a 1937 paper by Fischer in Ann. Eugenics. -- Jitse Niesen (talk) 09:39, 1 April 2007 (UTC)

Yes, there is more than one traveling wave, moreover the formula made no sense - surely the wave speed does not depend on a. For all I known it might have been the correct formula but context messed up by the author from Eqworld; I'll need to look up the references they cite when I have time. Kolmogorov et al have detailed analysis and it is also outlined in Grindrod. Fisher (1930) was cited by Kolmogorov et al but I do not have it. Do you have a copy of Fisher (1937)? Reaction-diffusion equation looks much better now, very nice context. It needs some meat (=math). If you want to move the 2nd half from Fisher's equation there go ahead. I am reading up on reaction-diffusion equations now from Grindrod in a hurry because I put that on someone's exam. I may end up writing some notes on the phase-plane method in LaTeX for my own use that could be wikified automatically. Jmath666 16:02, 1 April 2007 (UTC)

Here we go. From the abstract of the Ablowitz citation:

The travelling waves for Fisher's equation are shown to be of a simple nature for the special wave speeds $c=\pm 5/{\sqrt {(6)}}$.... The general solution for this wave speed is found...

So this was not a general formula by any means but a parenthetical info. To put it back we'd need to get that paper and make sure it is quoted right but is it worth the bother? I have asked Mark for a copy out of curiosity anyway. Jmath666 16:29, 1 April 2007 (UTC)

Yes, I do have Fisher (1937). It does contain the PDE. It shows that any travelling waves have speed c ≥ 2 and that travelling waves do indeed exist for all c ≥ 2. The KPP paper considers more general reaction terms and it also appears to be more rigorous (though I didn't study either paper in sufficient detail to be certain about it).

I agree that reaction-diffusion equation needs more maths. I hope to be able to expand the article some time; the text at Fisher's equation will certainly be useful. The closed-form solution for $c=5/{\sqrt {6}}$ is perhaps not so important. I used it to test some numerical routines that I was writing at the time and that's why I added it to the article. -- Jitse Niesen (talk) 07:18, 3 April 2007 (UTC)

I'll see about adding the closed-form solution back when I get the paper. It is nice to have closed form in a special case. I wonder if there are really multiple waves, one for each C but not enough to test it myself. I have read the KPP paper hoping to learn the technique and I it is indeed a mess. Can you please add the Fisher (1937) citation? Jmath666 17:08, 3 April 2007 (UTC)

I added the Fisher (1937) reference. I left Fisher (1930) in for the moment; I'm not sure what to do with it. -- Jitse Niesen (talk) 13:47, 5 April 2007 (UTC)

Thank you. I'll see if I can put my hands on the Fisher (1930) book to verify the citation. Mark Ablowitz said he was sending me the paper so I should have it soon. Jmath666 18:08, 5 April 2007 (UTC)

Got the paper. Please look again now. Jmath666 23:51, 5 April 2007 (UTC)

Excellent. So there is a family of wave profiles, even when we restrict ourselves to the wave speed c = 5 / √6. I learnt something new today. -- Jitse Niesen (talk) 02:47, 6 April 2007 (UTC)

References for matrix multiplication

Hello Jitse,

I have added some pubs with random algorithms about approximating matrix multiplication. I want in the future to add a section about those algorithms. You can delete them or move them in discussion, until then. (I am working with these algorithms for my diploma thesis, so I think that I could contribute in this article.)Zmoboros 18:24, 3 April 2007 (UTC)

The Top Editor's Award Recipient

		The Top Editor's Award Star Recipient
		To Jitse Niesen, for his long time positive contribution to the Srebrenica massacre article from User Mozart Amadeus Wolfgang . (talk) Congratulations!

Use of dubious

U "hid" the dubious tag on http://en.wikipedia.org/wiki/Wikipedia:Template_messages/Disputes. There is a genuine dispute as to whether the statement is time appropriate. According to http://en.wikipedia.org/wiki/Wikipedia:Template_messages/Disputes this is the appropriate in line tag.

Can u explain to me what u did and why or point me to an article. Tom94022 05:33, 12 April 2007 (UTC)

(This in reaction to this edit of mine at Talk:Binary prefix.)

As Wikipedia:Template messages/Disputes indicates, the dubious tag is for placement in a Wikipedia article. It was placed at a talk page. I don't think we have a tag that statements on talk pages are disputed. It's also not clear, at least to me, what the dubious tag means in this context (what is "time appropriate?"). I think you should just explain in your own words what the problem is. -- Jitse Niesen (talk) 06:05, 12 April 2007 (UTC)

Wavelets

Thanks for putting the citation to my PhD thesis back on the Hilbert-Hermitian wavelet page. I'm trying to add a link to that page from the one about the Morlet wavelet, stating that the Hilbert-Hermitian wavelet has better properties for time-frequency analysis (it supercedes the Morlet wavelet). Sadly, it has been deleted by a trio of anonymous spam fighters. I wonder if you would be so kind as to help out. The content is in the history... Jon Harrop 22:16, 13 April 2007 (UTC)

Hello Jitse Niesen. This situation is a little more complex than Jon Harrop suggests. You might want to take a look at User_talk:Requestion/Archive_1#Jdh30_Warnings and User talk:Jdh30 23:15, 13 April 2007. The Jdh30 talk link is to an old timestamped copy because Jon Harrop has blanked his talk page 3 times so far. (Requestion 23:21, 13 April 2007 (UTC))

I commented on Talk:Hilbert-Hermitian wavelet. I think it's better to wait till the discussion there concludes before we go to the Morlet wavelet article. -- Jitse Niesen (talk) 13:00, 14 April 2007 (UTC)

I agree. This whole Jon Harrop situation has about 15 active threads in different talk pages scattered all over Wikipedia. It is becoming difficult to keep it all coherent. (Requestion 21:46, 14 April 2007 (UTC))

There is only a "Jon Harrop situation" because every time the guy makes a contribution now he is followed by requestion who then brings up the same spam disagreement. Which as far as I can tell has now been resolved by user:Femto. Requestion seems set on removing all material even vaguely assoicated with Jon Harrop because of some misguided belief that Jon is the root of all spam. As far as I can tell Jon Harrop has done some good work. He also provides free tutorials/ demos as well as commercial stuff. I know of at least two separate institutes using the Hilbert-Hermitian wavelet to analyse their work so I think the article should stay. And just in case (Requestion) - this is not Jon Harrop. I say this because I have noticed that each time a user makes a remark concerning any of the above and it doesn't agree with you that you accuse them of being Jon Harrop. Marie Mason 00:02, 15 April 2007 (UTC)

T-Integration Question

Are you OK? Hope you are in good health. Have not heard from you in a while. Mike

Thank you for your inquiry. The T-Integrator has the form

Xn = Xn-1+G*T(L*XDn+(1-L)*XDn-1). When G =1 and L = 3/2 the T-Integrator takes the form Xn = Xn-1+ .5*T(3*XDn-XDn-1). This is the Adams integrator much used for real time simulation for many years.

From the T-Integrator point of view, this integrator works well for explicite real-time applications because a lead of 3/2T accounts for a half sample period delay from integrand reconstruction and a full sample period delay when it is used in feedback loops (most linear real-time applications). If the integrator is use implicitly (some nonlinear real-time applicatioins), further tuning is usually required.

For reference, please read my book entitled "Mathematical Modeling and Digital Simulation for Engineers and Scientists, 2nd Edition"... John Wiley and Sons Pub.:Chapter on T-Integration. 1988.

Also, see http://members.aol.com/jsmith46ws/ni1.htm.

I hope this is helpful. Let me know.

Jon Michael Smith = User:Jonmsmith

Once you convince yourself, will you put the material on Adams method back in my contribution? jonmsmith 15:49, 17 April 2007 (UTC)

I have been unable to locate information about the cited "Journal of Mechanical Engineering Systems". --KSmrq^T 12:56, 16 April 2007 (UTC)

Civility

Please tell me that was some kind of Dutch humour that has not yet reached these shores? Jon Harrop 17:25, 17 April 2007 (UTC)

Right - so it's okay for Requestion to say and do whatever he likes to Jon Harrop but Jon is blasted for finally getting frustrated enough to retaliate. I'd say it was fairly obvious Jon wrote the comment tongue in cheek. I can't say the same for some of the comments Requestion has written about Jon Harrop and other users.Petdoc 11:17, 8 May 2007 (UTC)

Equipartition theorem

Hi Jitse,

I'm wondering whether you might have time to look over equipartition theorem, and maybe leave some comments on its scientific peer review. Any insights you could bring would be very welcome — thanks! Hoping that you're doing well after all this time, Willow 16:51, 20 April 2007 (UTC)

Hello

Hi,

Thanks for the welcome. I have been impressed with the extent and quality of the mathematics articles on Wikipedia. Nice to know there's a community here.

I feel pretty strongly that things like this are important, and that we have a responsibility to give back to it (OK, motherhood statements).

Mike Henderson --Mhender 13:48, 22 April 2007 (UTC)

Help needed

I'm looking for an uninvolved admin to help with dispute resolution. See the discussion near the bottom of my Talk page. Charles Matthews 20:50, 24 April 2007 (UTC)

I'm sorry, but I don't think I have enough time in the coming week to attempt to resolve the matter. -- Jitse Niesen (talk) 02:11, 25 April 2007 (UTC)

Your bot at WP:AfC

The page Wikipedia:Articles for creation/List seems to be getting somewhat long, and I noticed that your bot maintains it. I generally try to avoid messing with bot-scripted pages, so I was wondering if you could condense the April days into one month and, since it ended several months ago, the 2006 months into one year. Thanks. -- kenb215 talk 02:12, 2 May 2007 (UTC)

There's not much that can go wrong, but I understand your reluctance. Anyway, I archived it. -- Jitse Niesen (talk) 04:32, 2 May 2007 (UTC)

Singular value decomposition

I've no idea how this could have happened, but your edit at Singular value decomposition added a plus/minus symbol at the start of the article. No big deal, and I corrected it, but I'm letting you know in case it's a bug. Cheers, Jitse Niesen (talk) 00:24, 5 May 2007 (UTC)

Hi Jitse. I think the problem was probably me accidentally clicking on the ± button in the 'insert symbol' widget while verifying the bot's edit. Thanks for letting me know though. Cheers, CmdrObot 00:43, 5 May 2007 (UTC)

The Number of Contributions

Hi Jitse, How do I find out "the total number" of contributions that I submitted to Wikipedia? I need a total number. This contr section doesn't tell me exact number of contributions submitted. There must be a way to find out exact number. Bosniak 02:22, 5 May 2007 (UTC)

Wannabie Kate. Oleg Alexandrov (talk) 03:12, 5 May 2007 (UTC)

Clenshaw algorithm

I came across the Clenshaw algorithm today and found it really interesting. Would you happen to know of an efficient way to convert a polynomial into its Chebyshev form? --HappyCamper 19:19, 10 May 2007 (UTC)

The straightforward way to convert a polynomial from monomial form to Chebyshev form is via the normal formula for changing a basis. This takes $O(d^{2})$ flops (excluding the computation of the change-of-basis matrix) where d is the degree of the polynomial. I don't know of a more efficient way, but I don't know much about orthogonal polynomials.

I suppose you know of the Horner scheme for evaluating polynomials in their usual form ($\textstyle \sum _{n}a_{n}x^{n}$). That's very similar to the Clenshaw algorithm, and if anything more efficient. -- Jitse Niesen (talk) 00:46, 11 May 2007 (UTC)

OK, this makes sense. Thanks for your reply! --HappyCamper 16:04, 11 May 2007 (UTC)

80.200.73.228

Re [1]: Some explanation may be appropriate here: [2] it's copy-and-pasted wiki-stalking, just ignore. Femto 16:27, 11 May 2007 (UTC)

I'm almost tempted to request that the warning and Jitse's comment be reverted [3] at Talk:Hilbert-Hermitian wavelet. It is inappropriate in relation to the Notability criteria discussion that is going on but I feel it is loosely connected. Here is my logic: it started with User talk:Jdh30's giving me the finger warning [4], his constant calling me a vandal, and his numerous interruptions in unrelated threads. The behavior patterns match perfectly. User talk:Bully-Buster-007 is just mimicking Jon Harrop's actions which have now come full circle. I probably should of archived my talk page sooner but the Jdh30 case is still open. If either of you have any suggestions I'd love to hear them. My plan is to just stay calm and ride this out. It can't go on forever, can it? (Requestion 21:19, 11 May 2007 (UTC))

Weird. Looking at the background, it's clear to me that Femto's removal of the "warning" was the best thing to do. The comments are still available for all to see, but they don't make sense to people who don't know the context. But I'll accept it if you put them back in.

Requestion, I'll echo Femto: try to relax and ignore it. Sometimes it's clear that arguing won't work; then, just stop arguing. Perhaps leave the spam for a few days. It's not that important. -- Jitse Niesen (talk) 00:49, 12 May 2007 (UTC)

I agree, comment removal was the best thing to do. The last workforall.net link spam of User:Bully-Buster-007's I deleted was back on April 30th. Since then I've been trying in futility to explain the WP:RULES. Some people just can't follow rules. (Requestion 16:03, 12 May 2007 (UTC))

re Jeffrey Adams (mathematician)

OK, fair enough. But he should probably go to AfD. It's expected that any normally accomplished is going to write books and lead projects. Herostratus 15:35, 12 May 2007 (UTC)

Of course you are free to put the article on AfD. -- Jitse Niesen (talk) 06:36, 13 May 2007 (UTC)

Numerical algorithms template

Hi Jitse. You may be interested in the discussion I started at Wikipedia talk:WikiProject Mathematics#Template:Numerical algorithms. Thanks. Oleg Alexandrov (talk) 19:58, 12 May 2007 (UTC)

I'll monitor the discussion, but at the moment it's just everybody agreeing with each other. I need to see some good fights before I join in. ;) -- Jitse Niesen (talk) 06:36, 13 May 2007 (UTC)

Jon Harrop

Hey Jitse, I saw your nomination and started looking at Jon's userpage. I was just wondering if there was any chance that we could retain him and resolve the conflict he seems to have been at the center of. I would hate to lose a potential good contributer.--Cronholm144 04:01, 13 May 2007 (UTC)

I agree that Jon would be able to write some good articles. Unfortunately, I don't have time or energy to resolve the conflict. -- Jitse Niesen (talk) 06:36, 13 May 2007 (UTC)

Should I give it a shot? I am rather new but lack neither energy nor time at the present moment.--Cronholm144 07:55, 13 May 2007 (UTC)

That would be great. -- Jitse Niesen (talk) 08:02, 13 May 2007 (UTC)

Done (well not done but I left a nice message)here's hoping--Cronholm144 08:13, 13 May 2007 (UTC)

Sieve of Eratosthenes

Hi Jitse. Could you assist Talk:Sieve_of_Eratosthenes#A_Deterministic_Boolean_Approach. I'm not sure how to proceed, as the arguments are turning into "I think", and "I doubt", without citing or checking the reliable sources provided. I have cited reliable sources, the code works, and theoretically correct based on the logical text of the sources, and is neutral in content. This does not propose anything new, however not conventional. The submission, I believe, is in fact correct, as it meets the requirements based on reliable sources. I have yet to read anything that refutes the runtime complexity of the algorithm presented, as per the lengthy discussion in the "talk" link above. This indicates a lack of fundamental computer science knowledge in time complexity on the part of the arguer, yet is still trying to argue this with me. This is an algorithmic challenge (computer science), not an equation (mathematics). Thanks. --Ausples 06:14, 13 May 2007 (UTC)

I was just writing something in the talk page while you wrote this message. -- Jitse Niesen (talk) 06:27, 13 May 2007 (UTC)

That's really good timing. I've added hard data. --Ausples 13:41, 13 May 2007 (UTC)

Mathematics CotW

Hey Jitse, Its me again..., I am writing you to let you know that the Mathematics Collaboration of the week(soon to "of the month") is getting an overhaul of sorts and I would encourage you to participate in whatever way you can, i.e. nominate an article, contribute to an article, or sign up to be part of the project. Any help would be greatly appreciated, thanks--Cronholm144 22:37, 13 May 2007 (UTC)

Bot: Request to bot function

Hi, I like the work Bot does for AFC and I'd like to put in a request. Seeing as how many submissions get left behind, I want a marker put on pages by default, categorizing the pages into Category:Wikipedia article creation requests needing further review. The templates I'd like to work with are {{afc n}} and {{afc c}}, where n would be put on pages by default, not substituted, and then reviewers can change it to c when they finish a page. It's a bit difficult to describe, but I hope something can be done. ALTON .ıl 23:30, 14 May 2007 (UTC)

Okay. I changed the bot to add Wikipedia:Articles for creation/Archive header at the top of every page it archives. It should start doing it tomorrow (or the day after tomorrow, if I made a mistake). -- Jitse Niesen (talk) 01:50, 15 May 2007 (UTC)

WikiThanks

Thanks! We'll see how it works soon enough. ALTON .ıl 04:36, 15 May 2007 (UTC)

Indian Mathematics

Hi Jitse, I finally have some time to start doing a major revision of the page, which I had originally planned to do much earlier (after the RfC in March, recall your comments there). I hope you'll have some time to drop in every now and then and offer criticism. I have a bunch of books that I had ordered in March. Hope they will prove useful. Regards, Fowler&fowler«Talk» 01:35, 17 May 2007 (UTC)

.

Bon Jovi

Hi, Jitse!

This is no big deal – I'm just curious why this article is on the list of current activity in mathematics. I didn't find the article on Oleg's list, and I can't see a category tag in the rock and roll article that's even remotely close to math. Oh – I checked the page history, and it certainly appears as if your 'bot put this article on the list.

Weird, eh? DavidCBryant 15:20, 18 May 2007 (UTC)

Leila Katami

Can't see myself why being the daughter of someone famous makes her famous, she's clearly not notable for her maths. However, if others disagree, so be it. jimfbleak 05:11, 22 May 2007 (UTC)

Question on divergent series

Hi Jitse!, I have seen that in the last days the article on the divergent serie 1-2+3-4.... does not longer shows its star as a FEATURED article. Do you know what happened?. Best regards, Uruk (Spanish Wikipedia).

Replied on es:Usuario Discusión:Uruk -- Jitse Niesen (talk) 04:56, 27 May 2007 (UTC)

Bot MIA in AFC?

Hi there! Just wanted to let you know that no archive was made of yesterday's AFC yet. Thanks for all the work that your bot does for it!--Xnuala (talk)(Review) 01:27, 1 June 2007 (UTC)

Okay, I fixed it and the bot did its work today. Thanks for taking over for one day. -- Jitse Niesen (talk) 03:35, 2 June 2007 (UTC)

Thank-you! I appreciate your speedy response.--Xnuala (talk)(Review) 18:50, 3 June 2007 (UTC)

JP Holding / Tektonics Review

The recent activity on the Acharya S article brings up something that has bothered me for a while. I don't think an article written by JP Holding belongs in wikipedia, in the links or otherwise. His own WP article was deleted, and he doesn't meet WP:RS, especially considering the standards espoused in WP:BLP. ^^James^^ 09:34, 1 June 2007 (UTC)

I'm not really familiar with the whole situation. The criteria for having an article on Wikipedia or being a reliable source are different from those for external links. Nevertheless, you may well have a point. I habitually revert when IP editors remove material without giving any reasons (unless I can think of a good reason myself). I didn't look into it at all and won't oppose it if you removed the references to Holding.

PS: Sorry for the late reply. -- Jitse Niesen (talk) 23:34, 3 June 2007 (UTC)

Spectral Method

Hi Jitse,

This is Mark, I wanted to contribute to the spectral method page. I couldn't find your comments on the talk on my contribution - under which talk is it? I'm new to this, in case it's not obvious. Under my talk, your comments aren't there - perhaps I'm blind!?!

Thanks,

Mark

Replied on Mark's talk page. -- Jitse Niesen (talk) 23:34, 3 June 2007 (UTC)

COI Templates.

Hi, I'm sending you a message because of your involvement with the Wikipedia:Templates_for_deletion/Log/2007_May_18#Template:COI_and_Template:COI2 discussion. The result of the TfD was no-consensus, but there was a significant expressed consensus for editing the templates to bring them into line with good practice. Unfortunately this has not happened, and the templates have been left pretty much in the state they were before the TfD. Would you like to assist in bringing these templates in line with good practice? --Barberio 16:48, 5 June 2007 (UTC)

Melbourne meetup 6

Hi. This is a reminder to people on the Melbourne meetup participation list that the next meetup has been arranged for 19 June. Could you indicate on the meetup page your likely attendence, or otherwise. Regards. - Cuddy Wifter 23:20, 7 June 2007 (UTC)

Gram-Schmidt process - numerically stable algorithm

Hi Jitse,

I'm just programming the Gram-Schmidt process and I got a bit confused in the section "Numerical stability" of the Gram-Schmidt article. To my mind, the superscripts in the last equation are wrong (I already wrote a comment on that on the "discussion" page before I discovered I could contact you..). Shouldn't it be either u_k^(k-1) on the left-hand side or all superscripts plus one on the right-hand side? Also, I think the projection operators need an additional k subscript: proj_{uk,(k-1)uk,(k-2).Raneko 12:47, 14 June 2007 (UTC)}

Replied on Talk:Gram–Schmidt process. -- Jitse Niesen (talk) 13:28, 14 June 2007 (UTC)

Thank you for nothing

Hi Jitse Niesen, all of you admins are quick to blame me, but when others personaly attack me - all of you are quiet. This behavior constitutes complete lack of objectivity on your "admin" part guys, but it's okay, I am used to it. For your information, here is a personal attack against me that none of you reacted http://en.wikipedia.org/w/index.php?title=Muhamed_Hevaji_Uskufi&action=history . Total lack of objectivity on part of wiki admins. As you can see, this user Jedi Svinje personally attacked me by saying (you're a retard) just because I included fact that Bosnian language dictionary was published 197 years before the first Serbian language dictionary.Bosniak 05:56, 17 June 2007 (UTC)

Bosniak, that diff you cited was just garden variety vandalism by what seems to be a single purpose account. Revert and warn him. If he persists, then you should take it to the admins.

Looking at his contributions, he seems to have a problem with you in particular, perhaps you should work it out with him on his talk page (assuming that he bothers to log on again). Also, is the fact that the Bosnian language dictionary was published before the Serbian dictionary important to the article? Cheers and I hope your opinion of the admins here improves. --Cronholm¹⁴⁴ 06:18, 17 June 2007 (UTC)

I believe Jitse has plenty of objectivity. What he is probably low on -- understandably so -- is adequate time and patience to deal with ranting editors. Fairview360 23:43, 17 June 2007 (UTC)

Deleted Mark Larson

Would you be willing to help me understand why the page was not acceptable?

Thank you,

MNAikidoka 04:01, 20 June 2007 (UTC)

Unit matrix

I saw that you contributed to unit matrix. There is a discussion going on to change it to "matrix of ones". Perhaps you have an opinion on this, see Talk:Unit matrix--P.wormer 08:38, 22 June 2007 (UTC)

As I wrote there, I agree with the proposed change. -- Jitse Niesen (talk) 09:20, 22 June 2007 (UTC)