User talk:Anghel

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--Your friendly ProofWiki WelcomeBot 19:30, 29 October 2012 (UTC)

Proofread category

I noticed your adding of the Proofread category on pages you are creating (this may or may not be conscious). To make such references easier to understand, it is preferable to invoke them only through the associated templates (the same holds for Stubs and other maintenance categories), in this case Template:Proofread. --Lord_Farin (talk) 22:56, 5 December 2012 (UTC)

My extension of Schur's Theorem (Ramsey Theory)

You have removed it. I don't see a trace of it, nothing (I even didn't know that one can do such a thing on a wiki). Please, give me back my copy promptly. And next time don't be so callous and such a vandal about someone else's work. True, I am not going to contribute to this wiki anymore, be glad. But I want my copy anyway, I am serious about it, I insist Wlod (talk) 21:23, 25 December 2012 (UTC)

Your work can be found in the history of this page. I'm sorry I made you angry, but please understand: because you edited a Template, your edits showed up in every other page that used this template, including pages such as Carathéodory's Theorem (Analysis) and Definition:Cauchy Sequence. You will admit that it would be confusing for the readers to find notes about Schur's Theorem when they thought they should read about Cauchy and Carathéodory, right?
Please, don't leave the wiki because of me; I'm a plain editor like you, and have no modly powers. Give it a couple of days and think about it before you leave completely? --Anghel (talk) 21:38, 25 December 2012 (UTC)
Wlod: It's in the wrong place anyway, and no attempt has been made to put it into house style. Please learn to use how this wiki works before posting. Others can do it, surely a clever and authoritative leader like you can too.
Accusing fellow editors of being callous vandals, btw, you may find that you don't have a choice over whether you contribute to this wiki any more. Please be more polite. In return I will try to unset your bozo bit. --prime mover (talk) 00:11, 26 December 2012 (UTC)

Sources and the prev/next construct

Brave work on maintaining the flow of 1965: Seth Warner: Modern Algebra on the addition of the Equivalent Matrices may not be Similar page. It's worth bearing in mind:

a) Unless you actually have the work, or can access the particular section (for example) on line, it is usually not a good idea to "guess" the position of the page you are entering. In the course of the flow of the actual work, it may not even exist, or if it does, not in the place in the work you'd "expect" it to exist. (In this case, though, its logical position was as it is indeed placed.) Of course, if you do have access to it, then this advice does not apply.
b) Don't forget to adjust the "previous" link of the page that the new page links to. That is, if you insert page C between A and B, not only do you change the "next" of A to point to C, you also change the "prev" of B to point to C, while making A the "prev" of C and B the "next" of C. (In this case it was Definition:Rank/Matrix which still pointed to Similar Matrices are Equivalent.) Otherwise, going back through the book you will miss the new page you added. (It's easy to miss - I've got this wrong a few times myself - it's only by having gone back to some of these pages to review them that I have found some discrepancies.)

As I say, it appears that this is a particularly trivial point to make a fuss about, but there is someone out there (not me!) working on a master's thesis whose content includes an investigation into the use of the presentational style as defined by ProofWiki compared with the (necessarily) linear style of presentation as you find in a book. The idea was to superimpose on the ProofWiki database the various linear orderings imposed by the works in question. As such it may be the case that this prev/next implementation is crucial. --prime mover (talk) 23:50, 12 January 2013 (UTC)

I do not know if you make bots prime.mover but it may be worth it. Considering how regularly structured the site is I believe a decent first project would be to create a loop alert in the sources checker (please bear in mind, I have no concept of the difficulty of such a task). The content pages are essentially just text files aren't they? Is there anyway I can get a hold of those? I would be doing so purely in my own interests. I believe I could create a program to convert the database into relevant GML script for visualization. --Jshflynn (talk) 00:36, 13 January 2013 (UTC)
Whoosh. (That was the sound of what you said sailing right over my head. :-) --prime mover (talk) 00:49, 13 January 2013 (UTC)
As in what I was saying was rude? I apologise if it appears that way as the last thing I want to be is rude (what's the point?). I was trying to make a suggestion that would cut down the tremendous amount of work you already do.
Or as in it was a flawed idea? In which case I would really appreciate constructive feedback. Thanks. --Jshflynn (talk) 01:15, 13 January 2013 (UTC)
English idiom: something goes over one's head if one does not understand its meaning at all. --Dfeuer (talk) 01:22, 13 January 2013 (UTC)
In that case I will try to explain myself better.
I believe that the content pages of ProofWiki are just a bunch of text files and that it's possible for me to have a folder on my desktop containing a bunch of files like Definition:Topology.txt the contents of which is exactly what's in the textbox of when you edit the page Definition:Topology.
Then I would use create a Macro in Microsoft Excel to go through those files and analyse their structure for all sorts of interesting things.
In particular I would use it to create a GML (Graph Modelling Language) script which basically is a language used to create graphs.
I would then open that script in Cytoscape (a great piece of freeware for visualizing graphs). And then Viola! I would have a graph about proofwiki.
What kind of graph exactly? My first project would be to create a graph of all the definitions of proofwiki because they're a little bit more regularly structured than theorems. Showing which depends on which.
I think it would be very cool to know which words are pendant vertices so to speak. Which have really high degree and so on. As Joe (and possibly prime.mover I'm not sure) has access to the wiki's database I would really appreciate having the text files so I could do this. --Jshflynn (talk) 01:38, 13 January 2013 (UTC)
It would be cool idea to check for loops in the graph to avoid circular proofs. Something like Theorem A is used to prove theorem B, which is then used to prove theorem A. If you're serious about this project, you should ask for a database dump of the wiki - I know it's been done before. --Anghel (talk) 12:47, 13 January 2013 (UTC)
There's a database dump done every day and stored here. I think it would be worthwhile to have some sort of interactive graph that woudl allow you search "zoom" in/out on particular concepts/definitions/theorems to see where they come from and what they lead to. --Joe (talk) 18:50, 13 January 2013 (UTC)

(To prime.mover): Thanks for the advice, and the correction - sorry I missed the linking on page B. As you figured out, I was a little too bold in my refactoring - but I wanted to try if I could figure it out. In the list of most read theorems on ProofWiki, there are quite a few that needs to be refactored simply because the proofs are too long. Eventually, I would like to help you with removing these refactors. --Anghel (talk) 12:47, 13 January 2013 (UTC)

Certainly - such help is welcome. But as I say, when doing the refactoring, all you need to do as regards the prev/next links is to place the { {WIP|Review links} } or something of the sort in the "Sources" section - unless you have the work in question and can directly follow the flow. --prime mover (talk) 13:38, 13 January 2013 (UTC)
I will try that at the first given opportunity. --Anghel (talk) 13:50, 13 January 2013 (UTC)

More refactoring instructions

When you refactor pages with sources on the bottom with prev/next links, please do not feel you need to remove the "prev/next" from the new sources on the subpages to which you do the refactoring. It is convenient, once it has been determined which specific page the source applies, to click on those links to get to the adjacent pages without having to go back to the master page and transfer those links over.

Sorry about all these instructions - when I initially conceived of the concept of refactoring the pages into the current format, I had taken it for granted that this was an exercise which would be undertaken by experienced editors who knew their way around this site in considerable detail. Therefore it was not considered a priority to assemble a list of instructions as to how it should be done. --prime mover (talk) 19:35, 21 January 2013 (UTC)

Point taken. --Anghel (talk) 21:14, 21 January 2013 (UTC)
Another suggestion: Suppose you have page A, for example, which contains a source reference with a prev/next pair. (Take for example Radius of Convergence from Limit of Sequence.)
Suppose you want to add a second section (in this case a Complex case). You then copy the (existing) real case into the subpage, and add the complex case as a second subpage.
Now: the existing citation was relevant to the existing page. So it makes sense to transfer that citation complete (aw, no, please don't remove the prev/next links, that's a real arsepain), as this citation fairly obviously is only relevant to the real case.
This saves a lot of work, and saves me missing the fact that these source references need to be moved.
As I say, I did not originally consider these instructions necessary because (a) I believed that it was only people who are seriously knowledgeable about this site and its contents who would be doing this work, and (b) I foolishly believed that the intention of these prev/next links was sufficiently intuitively obvious that they didn't need explaining. Apologies. --prime mover (talk) 22:54, 24 January 2013 (UTC)
So as to comfort your mind: I intend to rework Help:Editing and in the process, seriously amend it. It will (hopefully, in due time) feature a detailed manual of how to construct and maintain each of the standard sections we have come to use. --Lord_Farin (talk) 22:58, 24 January 2013 (UTC)
The prev/next links are obvious enough; I just find it hard to decide whether they're still relevant, since some theorems have almost similar real/complex cases. I am happy to leave such decisions to the seriously knowledgeable around here.
By the way, I've just finished refactoring the Definition:Primitive (Calculus) definition after adding a complex case. Here, I decided to leave the source links, since most of the material there also have relevance for the real case. --Anghel (talk) 23:16, 24 January 2013 (UTC)
The default position is that such pages are categorically still relevant. Generally speaking, if a book has prev/next links, then it exists in more-or-less entirety. If there is no reference to (for example) the complex case in a page being amended in such a manner, then it's a fair bet to assume that the book doesn't cover complex analysis. --prime mover (talk) 06:22, 25 January 2013 (UTC)


Please don't feel you have to be ultra-zealous in refactoring. It's a worthy aim to work towards, but if it is not obvious what the best form of that refactoring is, DON'T DO IT.. Please.

I am gradually working my way through the work on this site, bit by bit, and putting things in the form that I have envisaged as I go. While I appreciate that someone else doing it saves me the pain of doing it, it is often the case that if it is not in the shape that I imagine it, I have to re-do it. --prime mover (talk) 23:08, 24 January 2013 (UTC)

All-caps advice promptly taken. The reason I refactored Definition:Primitive (Calculus), which I wasn't entirely sure about, was that I needed to add a complex case, so I thought I might as well refactor the entire page - generally, the pages that I refactor are of two kinds: 1) They are definitions where I have to add a Complex Case, and 2) they are on the 200 most viewed list of pages, which (I think) make them a priority to refactor. --Anghel (talk) 23:16, 24 January 2013 (UTC)
Good work, by the way - I think it is still probably worth separating out Integration into its own page, but whether to transclude or Also see still needs to be decided. --prime mover (talk) 06:39, 25 January 2013 (UTC)

so far

Just want to say that the work you've been doing on complex analysis is really good. --prime mover (talk) 22:42, 27 January 2013 (UTC)

Awesome work on the well-definition of "interior of polygon". The number of lines required to prove that is... scary - much longer than I remember. Similar to proving things rigorously in homotopy theory; those "intuitive" homotopies are often nauseatingly evil when explicitly written down in formulae. --Lord_Farin (talk) 13:00, 9 February 2013 (UTC)
The number of lines needed is inversely proportional to the amount of handwaving. In fact, I've glossed over a few details myself, but I've also drawn an illustration which will be uploaded once the proof goes public on the main wiki. --Anghel (talk) 22:58, 9 February 2013 (UTC)

Welcome back

I feared you'd vanished. --Dfeuer (talk) 16:47, 4 March 2013 (UTC)

Welcome back again

Good to see you contributing again. --prime mover (talk) 06:30, 14 August 2022 (UTC)

Thanks, and nice to see you are working just as tirelessly as you were nine years ago. Anghel (talk) 17:35, 14 August 2022 (UTC)
Given you "trusted" status, and I believe you may now move pages (again). The site was upgraded some while back and the privilege to move and delete pages now needs to be specifically granted. Let me know if you cannot see the tools for moving / deleting. --prime mover (talk) 21:44, 14 August 2022 (UTC)

Bounded Metric Spaces

Quick question: where do the definitions 3 and 4 for bounded metric space come from? While they do indeed form valid definitions, we implemented a policy some time back that we would not introduce arbitrary extra definitions of an already-well-defined concept purely on the existence of an equivalence proof -- we prefer that all definitions actually come from a source. Otherwise we could potentially have arbitrarily long lists of definitions which may have dubious practical usefulness as a definition. --prime mover (talk) 22:42, 15 January 2023 (UTC)

Added a source to Definition:Bounded Metric Space/Definition 4.
As for Definition:Bounded Metric Space/Definition 3, it is based on your request on Boundedness of Metric Space by Open Ball that it should be added as an alternative definition. --Anghel (talk) 23:12, 15 January 2023 (UTC)
Essential information to have. Please can you put a {{|TL|NoSources}} template on it and a mergeto from and to that page so that I don't forget to tidy that up? My bad, I was too lazy to do it myself. --prime mover (talk) 23:21, 15 January 2023 (UTC)