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May 15

Python pre and post for loop terminology

I'm having trouble finding a reference for the proper terminology of two kinds of for loops in Python. The first one is the normal: for x in a: x+4 (I know this doesn't do anything, it is for this example) The second one is kind of backwards: x+4 for x in a What is the name of the for loop when the calculation comes before the "for" keyword? 75.136.148.8 (talk) 14:15, 15 May 2024 (UTC)

The second one is a list comprehension, not a for loop: https://docs.python.org/3/tutorial/datastructures.html#tut-listcomps Variouspotatoes (talk) 17:24, 15 May 2024 (UTC)

Thanks. I didn't think to jump to the data structures section of the documentation to look for it. 75.136.148.8 (talk) 18:21, 15 May 2024 (UTC)

It is only a list comprehension when enclosed between square brackets. Enclosed in curly braces, it becomes a set comprehension.  --Lambiam 14:08, 16 May 2024 (UTC)

And in round parentheses a generator expression. --Wrongfilter (talk) 15:12, 16 May 2024 (UTC)

May 16

payment aggregators and payment gateways

Is it accurate to categorize payment aggregators and payment gateways as payment infrastructure providers or payment system providers? What distinction would be more precise in describing their role in the payment ecosystem? Grotesquetruth (talk) 05:14, 16 May 2024 (UTC)

May 17

I can't pass "Fundamentals of Data Structures" (FDS) and "Advanced Data Structures and Algorithm Analysis" (ADS) no matter how hard I try

I am having a very serious issue with the two aforementioned courses in university (for context, note that I am in university in China, and I am Canadian). I can't understand the content at all, especially when it mentions anything mathematical or mentions a complex algorithm or data structure with names that I can't even remember. (It has nothing to do with the language, since the course content of these two courses are in English, which is my native language.) FDS started out fine, with the basic lists, stacks and queues, which I am more than familiar with and can confidently answer any questions about, but when it got to various kinds of trees, I can't remember them or any of the required algorithms that are to be used on them. I already failed the FDS exam twice. On the previous attempt, I fell short of the passing grade by just ONE multiple choice question, which made me very frustrated. ADS is even harder, with mathematical formulas relating to the algorithms that I don't understand at all. What makes it worse is that although there are two opportunities to attempt the FDS exam every year (in the fall and spring semester), there is only one opportunity to attempt the ADS exam every year (in the spring semester only). I didn't have any issues with any other courses such as C, C++, web programming, computer networking, information security, large-scale databases, etc., but these two courses are giving me stress. What's worse is that there is a 6-year limit (including taking a year off), so I can't take a break from university and come back to this any time I want, and my dad, who funds my studies, is threatening to stop doing so, since he said to me (in Chinese), "If you can't pass this required course, then your entire program has no point for you, since you can't graduate without it. You'd be better off going to a [community] college back in Canada, where the content is easier, and I can stop paying rent every month and being so far away from my family, and you can be closer to your friends back in Canada [with sarcasm]." What should I do to learn the data structures and algorithms that are completely obscure to me and pass the course? This is the only course that is stopping me from studying normally, because it seems that when I even try to rewatch the course content, I still am unable to understand it.

As a little aside that is completely unrelated to the academic problems, it seems that my dad has a drinking problem. He keeps buying large packs of beer despite my requests for him to stop, using excuses like "it's on sale" (Taobao perpetually displays it as on sale) or "it's nostalgic" (since the beer is Harbin beer, the city where he grew up), and I often see large quantities of empty beer cans piling up, and because of this, he has become very short-tempered, which negatively affects my mental health. What can I do about this issue? Félix An (talk) 03:45, 17 May 2024 (UTC)

Your second question is not related to computing. Intervening in someone's addiction when they are in denial is generally almost impossible. I am not familiar with Chinese culture, but I know filial piety, showing the utmost respect to one's parents, is a corner stone of traditional Chinese culture, making any potential steps even more problematic than they are in modern Western society. About the only thing I can think of is discussing your concerns with other older relatives in the hope that they can help.

Your first question is perhaps also not directly about computing and more about learning. You wrote you had no problem with C and C++; does this mean you can write programs in these languages (or in Java or Python)? In that case, I suggest that you write code for implementing various kinds of trees, such as AVL trees, red–black trees and 2–3 trees, or whichever kinds are treated in the FDS course. It will help to make the theory come to life. Even if you ultimately fail this course, the exercise will improve your skills and thereby your chances in your future life.

Do you use a textbook for the ADS course? You write that you do not understand the mathematical formulas. Do you mean you do not understand the meaning of a formula such as $O(n\log n),$ or merely fail to see how it relates to a given algorithm? Does the course material just present the formulas, or does it show how they are derived? If not, you can probably find the derivations or proofs online, sometimes here on Wikipedia. Studying the derivations until you could present them yourself to a fellow student will definitely help to understand and remember the formulas.  --Lambiam 10:12, 18 May 2024 (UTC)

For one thing, I think you should take FDS and do well in it before taking ADS. Bubba73 ^{You talkin' to me?} 01:22, 19 May 2024 (UTC)

May 18

What happened??

Formerly, when I did a Google News search clicking on "Tools" allowed me to sort the articles by relevance or date. Now, however, this is gone; clicking on "Tools" just doesn't do anything. What happened?? Georgia guy (talk) 16:01, 18 May 2024 (UTC)

@Georgia guy Are you on mobile or web? You haven't given enough information. Also, note that some things you see on Google these days are more experimental, sometimes, they won't be there for long. thetechie@enwiki: ~/talk/ $ 18:13, 19 May 2024 (UTC)

The web. Georgia guy (talk) 18:18, 19 May 2024 (UTC)

May 19

GNOME issue with gestures

Hello, I recently installed both Vanilla GNOME and Ubuntu GNOME on my Linux Mint machine lately to try out the gestures, but they don't seem to work on my computer's touchpad. I tried the three and four finger swipes, but they don't work. I tried disabling tap to click. Still nothing. The model is HP Pavilion dv6t-6c00, with Beats Audio, 8 GB RAM, no AMD Graphics, and came with Windows 7 Home Premium preinstalled. (Also, GNOME just doesn't look like how modern GNOME screenshots look, the top right menu looks very different.) Any help would be appreciated. If you reply here, please ping me. thetechie@enwiki: ~/talk/ $ 17:59, 19 May 2024 (UTC)

More info: I am using Wayland and a Synaptics touchpad, which should meet the requirements. GDM3 is also set as the default display manager on my computer. thetechie@enwiki: ~/talk/ $ 21:01, 19 May 2024 (UTC)

Never mind, I figured it out. My touchpad doesn't support gestures. *oh well*

Resolved

thetechie@enwiki: ~/talk/ $ 02:55, 20 May 2024 (UTC)

*sighs* thetechie@enwiki: ~/talk/ $ 02:55, 20 May 2024 (UTC)

May 21

Unicode strikethrough

I've been trying to do strikethrough with Unicode. I'm finding that the composed characters are to the right of where they "should" be, and somewhat too low, see the examples on our article, and in the combining character article, these are not in the correct position to be a traditional strikethrough. In fact the tools I've used work best if the struck through text is preceded with a "space strikethrough" (and no strikethrough at the end?). Is there a better solution in Unicode? All the best: Rich Farmbrough 21:00, 21 May 2024 (UTC).

Implementations of combining characters tend to be plagued by bugs. The precise appearance, including positioning and kerning, is not regulated by Unicode but by the rendering engine of the browser, using its font tables for the specific font. Here are examples of plain and struck-through vertical bars in a few typefaces, using U+0335.

Times New Roman:

||||||||||

|̵|̵|̵|̵|̵|̵|̵|̵|̵|̵

Courier:

||||||||||

|̵|̵|̵|̵|̵|̵|̵|̵|̵|̵

Courier New:

||||||||||

|̵|̵|̵|̵|̵|̵|̵|̵|̵|̵

Comic Sans MS:

||||||||||

|̵|̵|̵|̵|̵|̵|̵|̵|̵|̵

For me, using Firefox on macOS, the effects are quite varied across these fonts. Using Safari, the effects are also varied, but markedly different. The widths of ⟨|⟩ and ⟨|̵⟩ differ for each typeface on Safari. The struck-through bars are narrower for Comic Sans MS. Not only are they 226% (!) wider than the vanilla bars in Times New Roman, but they are even 33% taller, which I find quite bizarre.  --Lambiam 10:40, 22 May 2024 (UTC)

May 23

Organizing text and data

I'm working on a project that would go lot more smoothly if I could get myself organized. What I've got is pieces of text that I need to be able to classify in various ways and apply attribute tags to (e.g. this text has the tags applied for "Religion" and "Finances" while this other one has only "Animals", etc.). I would normally use Excel for something of this scale, but the text pieces aren't really appropriate for stuffing into a cell (and some have particular formatting I'd like to preserve, which again doesn't work great with Excel). At this point, my plan is to indeed do it in Excel, but hyperlink the text pieces, which is clunky at best. Any other options that spring to mind? There will be hundreds of records, which is large enough to need organization, but not zillions and zillions and it's a personal project, so I'm not looking to spend a lot. Any programs spring to mind as appropriate? Matt Deres (talk) 14:58, 23 May 2024 (UTC)

You could run a local copy of MediaWiki (the operation of which you are already very familiar), using categories for the classification. It's an issue if you want to produce automated reports (e.g. "list all the text that is in category X"), but a small php script should be able to do that. -- Finlay McWalter··–·Talk 21:44, 23 May 2024 (UTC)

I would personally use MediaWiki. It is easy to install and use. But, you are describing a common use-case for NoSQL databases. 75.136.148.8 (talk) 11:19, 24 May 2024 (UTC)

Are these pieces of text each in separate files, or in one large file, or are they divided across several files, some of which contain several classifiable items? Almost all approaches require that you already have, or create, a unique identifier for each item you want to classify. Suppose you are done with the job of classifying. Presumably you want to make some use of the fruits of your labour. What kind of searches/queries/other uses do you envisage? The best approaches may depend on the answers. There is a risk of us trying to solve an XY problem.  --Lambiam 11:55, 24 May 2024 (UTC)

Fair questions. The use case is for organizing folklore snippets in such a way that I can 1) keep them organized, 2) apply different kinds of tags to them (source location, source date, topics, etc.) for ease of grouping them in various ways, and 3) ideally find ways to connect related bits (e.g. this piece and that piece are likely variations on the same theme). Some of the snippets are literally on scraps of paper, others are from printed sources, still others are from online sources (documents, web sites), and some are audio files I'll need to transcribe. My earlier point about formatting being important is because, especially for the transcriptions of the audio stuff, I'd like to be able to show stresses, pauses, emphasized words or phrases, that kind of thing. Nothing crazy (italics and bolding, mostly), but Excel's ability to word process within a cell is extremely rudimentary; it's just not meant for that work. Matt Deres (talk) 17:13, 24 May 2024 (UTC)

It appears to me that the lion's share of the effort will be in labeling (with unique identifiers) and archiving the snippets in a way that allows you to retrieve them by their labels. If you scan or transcribe the items, you can store them as files with the labels as file names. The system for associating attribute tags with the item labels can then be purely (vanilla ASCII) text-based, whether an Excel work sheet or a database. TerminusDB, a free document-oriented database, should be eminently suitable for your purpose. While perhaps overkill for the immediate future, investing effort in becoming acquainted with its use may pay off in the end as your collection grows and your investigations become more sophisticated.  --Lambiam 07:01, 25 May 2024 (UTC)

You might consider Obsidian (software), which supports tags [1]. But see also the various links and lists under "see also" on that page, and the categories. Personal wiki software, note taking software, there's a lot available.  Card Zero  (talk) 07:20, 25 May 2024 (UTC)

May 25

What's the name for the blown up texts so common in social media?

In social media, many simple texts go viral which have nothing special other than they are blown up to a picture. People may forward them because (a) it's dead easy and (b) they find them funny or they want to proselytize the expressed opinion to others. What are they called? You might consider them a subgroup of internet memes. However, they don't fit the definition “Two central attributes of Internet memes are creative reproduction and intertextuality.”, nor do they contain any other noteworthy creativity. Their only purpose seems to be that they're bigger than normal text so that they gather more importance. Even “eye candy” would be too flattering, so I'd rather call them "rectangular attention sinks". Maybe I'd better turn to a sociologist with this question.

Related tech question: Do any social media offer a way to simply filter and ignore these attention sinks? ◅ Sebastian Helm 🗨 09:41, 25 May 2024 (UTC)

Can you provide any examples of "blown up texts"? Do you mean texts as in a form of online messaging between two people, such as SMS? ―Panamitsu (talk) 10:06, 25 May 2024 (UTC)

For example an image that contains nothing but the text
Why's it always “nyc smells like pee” and never “my pee smells like the greatest city in the world”
(In this particular case, the image actually contains some user name who may have originally posted this, along with their picture, contrary to what I described above. But I picked this because I found it somewhat witty. And the user name and picture are not important here.) ◅ Sebastian Helm 🗨 14:28, 25 May 2024 (UTC)

In magazines and newspapers, they are called pull quotes. 75.136.148.8 (talk) 22:06, 25 May 2024 (UTC)

Interesting; I wasn't aware of that term. But that's not the same thing. If you want to transfer the term onto social media, it would have to be some text taken from a longer discussion, rather like people use bold face and capitalization in such discussions as here. The blown up texts of my question do not pull a reader to any source. Even in the case of the “nyc” example which happens to contain something that looks like an author alias and picture, there is no way to jump to the original discussion. So, they're neither “pull” nor “quotes”. ◅ Sebastian Helm 🗨 08:21, 26 May 2024 (UTC)

For clarification: pull quotes are pulled from the text, though I guess they are designed to pull you in as well. --142.112.143.8 (talk) 21:24, 26 May 2024 (UTC)

Hmm, that seems redundant. Or what would be a non-pull quote, then? ◅ Sebastian Helm 🗨 05:08, 27 May 2024 (UTC)

Pull quotes (in the original sense of the term) coinhabit the space with the text from which they were pulled, so in a print magazine the quoted passage would typically appear twice on a page: once in the running text, and once standing out on ts own in a blown-up font size. Normal quotes typically appear merely once and usually have the same font size as the surrounding text, or when displayed as a block sometimes a slightly smaller font size.  --Lambiam 10:23, 27 May 2024 (UTC)

Thanks for the explanation. So their name seems to be a misnomer: The non-pull quotes even have more pulling to do, since they have to pull the text from farther away. But that was only a detour from my original questions. Can we turn back to them, please? ◅ Sebastian Helm 🗨 15:22, 28 May 2024 (UTC)

Diffs

English Wikipedia is almost at 1,225,620,000 diffs, increasing at about 1000 every ten minutes or so I'm guessing. Is there a limit to this number in MediaWiki or the underlying software – cognate with the Y2K problem and the like?

(This is a throwaway question that just occurred to me, not a complaint or anything to take seriously or anything that I'm worrying about!) 46.69.215.187 (talk) 17:18, 25 May 2024 (UTC)

MediaWiki stores complete revisions (previous versions stored backwards deltas as diffs, but later versions store the whole revision and computes the diffs) in the REVISION table. The primary key for that is "int unsigned", which in MySql is a 32 bit integer. That's a max of 4,294,967,295; so that would put en.wikipedia at about 1/4 of the way to the limit. I don't know what provision the developers have for the (surely inevitable) case where that becomes an issue.-- Finlay McWalter··–·Talk 18:27, 25 May 2024 (UTC)

Ah, that answers my question and provides useful extra reading! Thank you @Finlay McWalter: I'm very grateful for your time and expertise. 46.69.215.187 (talk) 18:34, 25 May 2024 (UTC)

The reference document also states that there is a 64-bit integer data type, which is one possible solution. Robert McClenon (talk) 01:12, 26 May 2024 (UTC)

May 26

Word Autorecovery

I am using Windows 11, and Word for Microsoft 365. My question has to do with the feature to Save Autorecovery information, which saves a copy of each Word document that is open and has been modified within the past 10 (or other user-settable time) minutes. These Autorecovery files are saved in Appdata \ Roaming \ Microsoft \ Word. However, if I look at them as I am editing various Word documents, sometimes I notice that some of them have sizes of 0 KB. I am attaching a screen shot showing a view of the Word folder with four documents having sizes of 0 KB. These files are in fact null files; that is, the 0 KB is correct. The files that I was editing were not null files.

What causes Word to stop creating good Autorecovery files? What I have found I can do is to stop Word (after saving the documents in question to their disk locations), and restart Word. If there is an unexpected stop or unexpected loss of Word functionality, updates to the documents being edited are lost.

Is there technical documentation of the Autorecovery feature? Does anyone know what causes these failures, or how to minimize their occurrence? Robert McClenon (talk) 03:36, 26 May 2024 (UTC)

What follows is a hunch, although based on Microsoft sources. Buried deep in the menus of office is a way to change the autosave location. [2] Perhaps this will solve the problem. I base that on hints in this otherwise irrelevant page [3]. It has the phrase "the roaming profile has reached its maximum storage limit". What is the Roaming directory? It seems to be to do with making user data accessible across a network. Maybe avoiding the "roaming" will also avoid the zero bytes file issue.  Card Zero  (talk) 08:24, 26 May 2024 (UTC)

Thank you, User:Card Zero. The sources that you have provided are very old, which I think you knew, but they do provide information for an educated guess, which is what you were trying to do. You ask: What is the Roaming directory? That is displayed in the screen shot that occupies too much space just above this discussion. It is a subdirectory of my User directory, and, as you imply, it has something to do with network access, but appears to be an old version of network access. I have changed the directory in which the Autosave is being done,and will see if that accomplishes anything. I think that we are both inferring that what was happening was that the Word subdirectory within the Roaming subdirectory had exceeded some size limit, which would be why the Autorecovery files were being zeroed. You provided some useful information to guess at what to do. Robert McClenon (talk) 16:38, 28 May 2024 (UTC)

Yes. A couple of other completely different wild guesses, which I have no time right now to investigate, is that they are lock files (to do with exclusive access to a file in use) or placeholders (when there is no need for an autosave but it is somehow convenient to Word if it can find the appropriate autosave file anyway). Also I really ought to dig the previous similar discussion out of the archives, I forget how it concluded.  Card Zero  (talk) 20:23, 28 May 2024 (UTC)

"dracut"?

Where does the name of dracut (software) come from? --142.112.143.8 (talk) 04:38, 26 May 2024 (UTC)

Never mind, I found a Reddit thread with the answer. It's named after Dracut. I once read a novel where the "no resemblance to actual people" disclaimer said that "the characters are placenamed"; apparently some software developers had the same idea. --142.112.143.8 (talk) 05:10, 26 May 2024 (UTC)

Resolved

May 27

Ringtones for different known callers

Ringtone doesn't seem to mention that this is possible but I think it is. I tried finding sources but found nothing that Wikipedia would accept, and even then, nothing seemed to make it clear the concept even existed.— Vchimpanzee • talk • contributions • 22:36, 27 May 2024 (UTC)

Seems like that is part of the functionality of the software of the phone (iOS/Android), not part of the ringtone itself. Polygnotus (talk) 04:11, 28 May 2024 (UTC)

The best place to propose an improvement to any article is the talk page of that article. Shantavira|^{feed me} 08:13, 28 May 2024 (UTC)

As mentioned, it is the phone's software, not the concept of a ringtone. On my phone, I can go into my contact list, select a contact, and set both an image and a ringtone for that contact. Then, when I receive a call from that number, the image I set shows up and the ringtone I set plays. If I haven't set either one, the default image and ringtone are used. So, it is possible to have a ringtone for a specific contact on a phone if the software allows it. It is also possible to have a different ringtone on different phones. It is possible to have a ringtone that plays when you purchase the phone, but then a person changes it later to a different one. It is possible to play a ringtone on a piano without a phone at all. It is possible that a frog may learn to vocalize sounds that mimic a ringtone. A lack of references should indicate that concept of "possible" and "ringtone" is not in itself notable (but I would like to see that frog). 12.116.29.106 (talk) 11:20, 28 May 2024 (UTC)

I can't really propose an improvement where I don't have the reliable sources that would support it. That was my purpose in asking here.— Vchimpanzee • talk • contributions • 14:30, 28 May 2024 (UTC)

May 28

How to search for fake references (in SparQL or with other methods)

In SparQL, how can I search for stuff like this. So it would start with an opening square bracket, then a number of up to 3 digits, then a closing square bracket.

Is there a way to do this via the normal search box? Is there another, better way? Thanks! Polygnotus (talk) 04:07, 28 May 2024 (UTC)

I'm not familiar with SparQL, but a regular expression that will serve for a search in most query pattern syntaxes is:

\[[0-9]+\]

Thus will also match "[2024]". If 3 is a hard limit on number of digits, this might work:

\[([1-9]|[1-9][0-9]|[1-9][0-9][0-9])\]

 --Lambiam 10:13, 28 May 2024 (UTC)

Thank you. I think that the problem is that the article content itself is not on Wikidata, which means I have to try a different approach. It seems like the search function also does not like regex. So I may have to download a dump and use regex. Polygnotus (talk) 11:24, 28 May 2024 (UTC)