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January 22

Is any detailed information about Aaron Swartz's The Info Network available?

Thanks. Apokrif (talk) 03:35, 22 January 2021 (UTC)[reply]

The ArsDigita link from our Aaron Swartz article leads here, which is fairly detailed.--Shantavira|^{feed me} 09:16, 22 January 2021 (UTC)[reply]

Would it be useful to express -why- static variables are useful?

This page is pretty clear in describing what a static variable is, but while I am trying to learn about this, it might be useful to understand -why- they exist; the rationale for them and what benefits they offer - to the compiler, speed of resulting programme etc?

Just a suggestions, I am thankful for the record that exists!

https://en.wikipedia.org/wiki/Static_variable — Preceding unsigned comment added by 92.41.228.205 (talk) 17:06, 22 January 2021 (UTC)[reply]

Before high-level programming languages were developed, the most common situation was that all memory was statically allocated. One way in which functions in a program can communicate with each other is by passing information through parameters. But suppose that in an application there is a centrally important store of information that can be consulted and updated by various functions. In that situation, passing it around through parameters is awkward. The alternative is to use a global variable, which in most languages means it is allocated statically. Depending on the instruction set of the processor, accessing static variables may be faster than accessing dynamic variables; the latter may involve some indirection and pointer arithmetic. --Lambiam 21:15, 22 January 2021 (UTC)[reply]

Static variables will typically have storage reserved at compile-time. This means no memory needs to be allocated for them at run-time, which can be important in constricted environments such as embedded systems with strict memory limitations. This also means a given static variable has a fixed memory address, which can be necessary for low-level stuff like device drivers. --47.152.93.24 (talk) 03:56, 23 January 2021 (UTC)[reply]

Change in key's meaning

I use Google Chrome. Traditionally when I press F6 it takes me to the URL bar where I can edit the URL I'm at. But now when I press F6 it highlights my current tab. Any reason the F6 key's function changed?? Georgia guy (talk) 18:08, 22 January 2021 (UTC)[reply]

Oops, just after I saved my edit, F6's behavior was back to normal. Georgia guy (talk) 18:09, 22 January 2021 (UTC)[reply]

And now it changed again. Georgia guy (talk) 18:10, 22 January 2021 (UTC)[reply]

FWIW, you can also use Alt+D to access the URL bar. Elizium23 (talk) 21:36, 22 January 2021 (UTC)[reply]

Additionally, you can also use Ctrl+L as well. In the current stable release of Chrome, F6 once goes to URL/Search bar - a second time, highlights the Tab bar for keyboard navigation between tabs (instead of the Ctrl+Tab ↹ method). Andyhill7 (talk) 21:00, 26 January 2021 (UTC)[reply]

January 23

Archiving a page?

Could someone help me archive this: https://tniad.mil.id/tni-ad-turut-berduka-cita-atas-meninggalnya-letjen/? This is for an article of mine. Tried five times on web.archive.org but the website keeps saying "Live page is not available". Regards, Jeromi Mikhael 03:34, 23 January 2021 (UTC)[reply]

Although the domain tniad.mil.id is registered, my DNS gives: "cannot resolve tniad.mil.id: Unknown host", so it is no wonder that the Internet Archive does not find a live page. Ping gives timeout on both of the name servers ns1.mabesad.mil.id and ns2.mabesad.mil.id. This nay be a temoporary problem. --Lambiam 09:38, 23 January 2021 (UTC)[reply]

Does this motherboard support booting from pcie (GA-H81M-S1)?

I am thinking of buying this ssd CT1000P1SSD8 (a gen 3 x4 pcie) and then using a pcie adaptor to plug into this motherboard GA-H81M-S1 (pcie 2.0 x1), would the motherboard allow it to boot or it would be able to just be used from ram. The idea of not buying a sata ssd is that this faster pc can be used when I change this 4 years old pc for a better one and it will work (without some speed loss from pcie 3.0 x4 to pcie 2.0 x1).2804:7F2:598:BE0F:3D8D:9C65:28ED:3B91 (talk) 19:56, 23 January 2021 (UTC)[reply]

I do not think so. You need at least series 9 Intel chipset. Ruslik_Zero 20:55, 23 January 2021 (UTC)[reply]

Thanks for the information2804:7F2:598:BE0F:3D8D:9C65:28ED:3B91 (talk) 21:00, 23 January 2021 (UTC)[reply]

Assuming your computer has an unused USB port and can boot from USB (nearly all can), and you're willing to spend $10 or something for a small USB key, or alternatively don't mind a large one permanently sticking out and have one available, you have options. Even if there is no motherboard support for NVMe booting and you're not willing to add NVMe support to tbe EFI yourself, it is fairly trivial to enable NVMe booting by using Clover or similar especially if your motherboard supports EFI booting. The motherboard boots the USB, then the USB boots the NVMe drive. I'm doing it myself on one system, indeed I just changed from an older Clover to Refind with NVMe driver added then to a new Clover then back to Refind with ease although I did have another system available to easily modify the USB when I screwed up. (The reason for changing was unrelated to the NVMe device.) However it's worth considering whether you're actually likely to gain anything from this set-up especially given you're restricting the maximums of the drive and that this sounds like a fairly old system and the benefits of NVMe are often small in a lot of non synthetic workloads. Nil Einne (talk) 15:33, 24 January 2021 (UTC)[reply]

January 24

Taskbar Stops Working

This has happened to me either twice or three times. I am using Windows 10, and Office 365, and Firefox, and Opera. (I know that someone will say that I can use one browser or another. I know. I have my reasons.) I normally switch between applications by mouse-clicking on the program icon in the task bar at the bottom of the screen. What has occasionally happened is that the task bar has stopped working. The mouse no longer will focus on the icons in the task bar. This means that the only way to switch between applications is to click on the window for an application, which of course is only possible if a portion of the window is visible. I may be able to shrink the window that I am in and expose part of another window to click. Also, when the task bar stops working, the clock in the lower right corner stops updating, perhaps because the clock is the extension of the frozen or vanished task bar.

So I have two questions. First, does anyone know what causes this? Is there a a post-mortem way that I can determine what caused this? Second, is there a way to recover from this, to make the task bar come back to life? Each time, I have restarted the computer; but to restart the computer when the task bar is frozen, it is necessary to bring up the security menu with Ctrl-Alt-Del.

What causes this (if it has a known cause)? What can be done to undo this, short of a restart? Robert McClenon (talk) 02:48, 24 January 2021 (UTC)[reply]

Robert McClenon, you know that you can switch by using Alt+Tab ↹ or ⊞ Win+Tab ↹? Elizium23 (talk) 02:56, 24 January 2021 (UTC)[reply]

Does this tutorial on restarting Windows Explorer help your situation? Elizium23 (talk) 02:58, 24 January 2021 (UTC)[reply]

Thank you, User:Elizium23 - You have given me at least two useful items of information. The first is that the problem is caused by the Windows Explorer thingy freezing. We don't need to know what causes that to be able to figure out what to do about it. The second is how to restart the Windows Explorer thingy from the Task Manager. Robert McClenon (talk) 04:10, 24 January 2021 (UTC)[reply]

You can also use Ctrl+⇧ Shift+Esc to start task manager. LongHairedFop (talk) 20:42, 24 January 2021 (UTC)[reply]

Windows Explorer is the part of Windows that generates the Taskbar and other on-screen stuff that makes up "the Windows desktop". Make sure your Windows installation is up-to-date. If it is, and this keeps happening, the easiest thing is to just reinstall Windows. Odds are good it's caused by some messed-up Windows file somewhere. Windows 10 makes it pretty easy to reinstall without nuking your personal stuff, though you should always back up. Do a Web search for "windows reinstall" to get details. --47.152.93.24 (talk) 19:32, 27 January 2021 (UTC)[reply]

@Robert McClenon:, it sounds like your PC has a number of accumulated problems. I would suggest that a local PC repair business with a Microsoft Accreditation would be your best bet. I used to do this for a living, they should be able fix it for around £40-50. My experience was with Windows XP, but some of this should be revelant.

1. You can end Explorer as a process with Task Manager. Highlight it and press the 'Delete' key. You should be able to restart Explorer (or any other process) within TM by clicking File → New Task (run) → enter "Explorer". Your mileage may vary.

2. If you have an antivirus program installed, make sure it is up to date and run a complete scan. You may only have MS Antivirus. In my opinion it's better than nothing, but nothing more. If not, try installing Malwarebytes (free version, ignore prompts to buy subscription) and run a full scan. Delete or quarantine suspect entries. Any problems in attempting to install or run any AV or malware scanner are almost certainly caused by the malware itself. Try rebooting and running in Safe Mode With Network. Usually press F8 after the BIOS check, just before Windows starts up.

3. In the old days I would have run a registry checker such as Registry Recycler, but I read that this is not recommended under Windows 10.

4. Has the problem of Explorer freezing happened recently, or has it been happening for a while? If recently, you may have installed something (deliberately or unwittingly) which has led to Windows' instability. You could try something like Windows button → Run → 'System Restore', and choose a date before the problem manifested itself (NB I don't have W10, so I'm just guessing as to the exact sequence.) In my personal experience, re-installing Windows of whatever version generally leads to further disaster. I'm not sure since I have little experience with W10, but you may well need the original CD/DVD and the Windows licence number, which may or not be be a problem. Best of luck, >MinorProphet (talk) 14:11, 29 January 2021 (UTC)[reply]

January 26

UK English in Word.

I'm in the UK and I'm using Microsoft Word. When I type a word like 'popularise' or 'specialise' it tries to tell me that the spelling is wrong and it suggests the American spelling of 'popularize' or 'specialize'. I've gone into settings and chosen the 'Language' option and then under 'Office Authoring Languages and Proofing' I've selected 'English (United Kingdom) preferred'... but it still keeps telling me that the US spelling is correct and my UK spelling is wrong. Am I missing something? — Preceding unsigned comment added by 95.150.37.129 (talk) 13:53, 26 January 2021 (UTC)[reply]

Select the text in your documetnt and look at the status bar, where it says: "Section 1 Page 1 of 1 ...". The fourth entry is the language. If it's "English (United States)", you need to click on it and select UK English in the dialog box. You can also change the language in the "Normal" style. When you modify a style, in the lower left corner of the Modify Style box select Format > Language. You might have to change the language of the Normal style in your Normal.dot template if you want every new document to start with UK English settings, altho you might also be able to change this in the Language tab under File > Options. 93.136.127.254 (talk) 14:41, 26 January 2021 (UTC)[reply]

The idea that the -ize suffix is an American spelling is a common misperception. See Oxford spelling. I work for a British publisher and we always use the -ize spellings.--Shantavira|^{feed me} 15:28, 26 January 2021 (UTC)[reply]

LibreOffice lets you use a wide variety of Hunspell dictionaries for assorted varieties of English, and as Hunspell dictionaries are open-source, you can customi[s/z]e them. You don't need to know how to program to do this. I do not know if you can use Hunspell with Microsoft Word, because Microsoft didn't give a very clear answer to that question.[1] I'm fairly sure you can also just add 'popularise' and 'specialise' to the dictionary, even in Word. HLHJ (talk) 03:26, 29 January 2021 (UTC)[reply]

Copyright question

Hi! I found an unpublished book online. I can read it as a pdf or on a web page. I want to know if I can print it legally. The link is here. Thank you! Dswitz10734 (talk) 15:23, 26 January 2021 (UTC)[reply]

Also asked at Wikipedia:Reference desk/Entertainment § Copyright question. Please do not crosspost. --Lambiam 17:12, 26 January 2021 (UTC)[reply]

Internet Archive Search Engine

Is there a search engine that looks through internet archives? That would be equivalent to giving the WayBackMachine a good search engine. Charles Juvon (talk) 16:07, 26 January 2021 (UTC)[reply]

What Internet archives are you thinking of, other than that maintained by the Internet Archive? --Lambiam 17:14, 26 January 2021 (UTC)[reply]

@Lambiam: Thank you. The website link through Internet Archive you provided does accept keywords. The way I was accessing did not. Charles Juvon (talk) 17:27, 26 January 2021 (UTC)[reply]

Information about length of power cables on a power supply

Is there any accessible information online about the length of cables that are the output from a PSU? I am putting together a ATX build in a mid-tower and I encountered a problem I've never ran into before. The CPU power cable was not long enough to reach the port. Jdphenix (talk) 18:23, 26 January 2021 (UTC)[reply]

I suppose you can look it up at the site of PSU's manufacturer. Ruslik_Zero 20:18, 26 January 2021 (UTC)[reply]

You may be able to get an extension cable that plugs between the supply cable and the motherboard. Graeme Bartlett (talk) 20:53, 26 January 2021 (UTC)[reply]

An option for sure. I recall molex extensions catching on fire. I was just hoping that someone may have put together a database of detailed information about PSUs that I didn't know about. Oh well. Appreciate the help! Jdphenix (talk) 22:52, 26 January 2021 (UTC)[reply]

Outlook Trashing the Inbox After 2 Weeks

I am using Outlook in Office 365. I discovered on 25 January that all of my incoming email before 11 January had moved to the Trash. I copied all of the email to an archive (and will go through it and decide what to trash). Then today, on 26 January, I see that my incoming email from 11 January is in the Trash. There seems to be an option or switch set that is trashing the mail after two weeks. Where is it set, and how do I unset it? Robert McClenon (talk) 20:31, 26 January 2021 (UTC)[reply]

Robert McClenon It's outlook bug because I too faced same problem, thats why I downloaded all my email data and uploaded to file hosting sites. Rizosome (talk) 12:38, 27 January 2021 (UTC)[reply]

Thank you, User:Rizosome - So it is a new Outlook bug? I didn't have the problem until 11 January 2021. It seems like a misfeature rather than a hemipteran (that's a true bug) because it sounds like something that someone would decide we ought to want. Robert McClenon (talk) 19:14, 27 January 2021 (UTC)[reply]

January 27

Technical name for Video editing effect

In some parts of this Video, there are wavy screen cornering effect is done , is there any technical term for it? Rizosome (talk) 12:00, 27 January 2021 (UTC)[reply]

Could you link - or at least mention - a time frame? A watched a few seconds and clicked around a bit but didn't see anything. Watching en entire 13-minute copyright violated wrestling video is a bit of a large ask. Matt Deres (talk) 18:57, 27 January 2021 (UTC)[reply]

Around @1:16, @1:42, @2:12 of the video, right side of and @2:30 of the left side got deviated. Is there any technical term for this deviation? Rizosome (talk) 13:38, 28 January 2021 (UTC)[reply]

Radiojon Jeremy Butler TomCat4680 Mrschimpf Rizosome (talk) 14:41, 28 January 2021 (UTC)[reply]

I think it is an unintended artifact of digital image stabilization, performed in post-production to reduce the shakiness of the image, apparently taken with a handheld camera. To stabilize the image, the individual frames need to be shifted, which means some border pixels have to be sacrificed. In case of an extreme excursion, there is a choice: allow a bad image shake to remain, sacrifice an extreme number of border pixels in the adjacent frames, or shift without such sacrifice, but then fill in the missing pixels. In this case the software used the third option, but instead of using some combination of interpolating and extrapolating, it used black pixels as fillers. I expect that the digital image stabilization community has names for the most common approaches to this issue, but I don't know what they are. --Lambiam 14:55, 28 January 2021 (UTC)[reply]

January 28

Windows 10: Screen stays displayed all night

This is about Windows 10 on a desktop computer. The screen has stayed displayed all night for the last two nights. That is, if I leave the system alone, the display is still on eight hours later. I have the Power and Sleep options set for when plugged in, turn screen off after 5 minutes, and, when plugged in, PC goes to sleep after 2 hours. But it isn't turning the screen off and it isn't going to sleep. (Well, I am going to sleep, and I could theorize that it does turn the screen off when I am asleep, and then turns it back on when it sees me. But we won't engage in that speculation right now.) Until a few days ago it was behaving as expected. This behavior, staying on all night, is new. What might have happened to cause this? Robert McClenon (talk) 15:00, 28 January 2021 (UTC)[reply]

It depends a lot on the species of screen and also on the cable you use. Check that the screen itself is set to auto-sleep. You should have a menu option to set a specific delay and also to turn the overall function on/off — GhostInTheMachine ^{talk to me} 15:14, 28 January 2021 (UTC)[reply]

Do you have any tasks running that might tend to inhibit sleep? A video player, for example? Updates or a dialog box displayed? Elizium23 (talk) 16:50, 28 January 2021 (UTC)[reply]

Since this is new behaviour, my recommendation is to force it to restart once and see if that corrects the behaviour going forward. Matt Deres (talk) 14:51, 29 January 2021 (UTC)[reply]

Do softwares cause screen flickering?

Lambiam RunningToMars Hohum I Uninstalled cracked IDM software in my laptop few days back. From then laptop runs smoothly without screen flickering. I thought screen flickering related to hardware problem.

Do softwares make screen flickering? Rizosome (talk) 15:59, 28 January 2021 (UTC)[reply]

While running, apps can make your screen do about anything. Since IDM runs in the background, it is theoretically possible. In particular, without mucking with the screen, it might interfere with the smooth display of streamed video if background downloads consume too much capacity of a strained Internet connection, leading to local congestion. Or it interposes itself between the receipt and the displaying of the media. Whether there is indeed a causal connection or the problem vanishing together with the uninstalling is merely a coincidence, is impossible to tell, but I saw a possibly related complaint here. --Lambiam 16:54, 28 January 2021 (UTC)[reply]

January 29

What devices really needed to solve P versus NP ?

I took interest in one of the open question: P versus NP problem. What devices really needed to solve it ? Rizosome (talk) 05:00, 29 January 2021 (UTC)[reply]

A quantum computer. Here is a nice easily understandable article: https://www.quantamagazine.org/finally-a-problem-that-only-quantum-computers-will-ever-be-able-to-solve-20180621/ 41.165.67.114 (talk) 07:24, 29 January 2021 (UTC)[reply]

P = NP is a purely mathematical statement, just like the Mertens conjecture, Fermat's Last Theorem and Goldbach's conjecture. The Mertens conjecture and Fermat's Last Theorem have lost their conjectural status: the former has been settled in the negative (the conjecture is false) and the latter has been solved in the positive (the conjecture is true, and it is indeed a theorem). The status of Goldbach's conjecture is still open; most mathematicians who have looked at, starting with Euler, think it is true, but the question may keep evading the combined ingenuity of all minds and remain unsettled forever. Precisely the same holds for the question whether the two complexity classes P and NP coincide or not. Most theorists think they differ, since no one has found a polynomial-time algorithm for any NP-complete problem, but that does not necessarily mean no such algorithm exists, and no one has found a proof that no such algorithm can exist. To settle the question requires a bright mathematical mind – whether human, an AI, or a hivemind – to come up with a mathematical proof of either the statement P = NP or the statement P ≠ NP. Neither more nor less is required. The devices needed are mathematicians. --Lambiam 09:07, 29 January 2021 (UTC)[reply]

What does "fillers" mean in video editing software?

From here , I want to know "fillers" mean in video editing context? Google didn't help me much. Rizosome (talk) 15:20, 29 January 2021 (UTC)[reply]

It's not a technical term. Sometimes the stabilization software will need to create a portion of the screen where there is no original video (because things have shifted during the stabilization process) and something needs to go there. "Filler" is a generic English term for anything that covers up or over gaps or holes in something, so that's the term that got used. It's the second sense listed here. Matt Deres (talk) 16:43, 29 January 2021 (UTC)[reply]

Specifying a file for both StdIn and StdOut in Java using Windows cmd

I have written the following Java class called Test.java:

import java.util.Scanner;

public class Test {
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		int value = in.nextInt();
		System.out.println(2 * value);
	}
}

I can run the compiled class file from the command line on Windows and have it use an arbitrary file for standard input by using:

java Test < file.txt

and I can do the same for standard output by using:

java Test > file.txt

How do I specify both an input file and an output file? --Puzzledvegetable^{Is it teatime already?} 15:53, 29 January 2021 (UTC)[reply]

Fairly certain that's just going to be this: java Test < input.txt > output.txt. Don't have ready access to a Windows machine, so I can't confirm. Jdphenix (talk) 19:09, 29 January 2021 (UTC)[reply]

SQL question - using MAX of a different field to find something else.

Let's say I have a dataset with customers, stores, products, sale dates, and prices. If I wanted to find the last sale date for an item I could do this:
select product, max(sales_date) from sales group by product
But what if I want to find the last sale price for each product from each store (and not include the sales date in the return)? It seems like I should be able to use a case statement including a MAX function, but that does not parse (as an aggregate; I thought maybe it would work as an analytic function, but it doesn't seem to be what I want. Basically what I want to be able to see is one product per one line and use CASE statements to split up the different stores into columns. Example:
PRODUCT NYC CHI TOR Carrots $15 $14 $18 Bananas $12 $10 $15
That doesn't seem crazy, but I can't seem to figure it out. Any help? Matt Deres (talk) 17:04, 29 January 2021 (UTC)[reply]