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June 6

youtube-disputes+3ncfuutagcay804

I'm currently in a dispute with YouTube and the email confirmation of receipt of my complaint came from outlandish youtube-disputes+3ncfuutagcay804(at)google.com (naturally not mentioned anywhere). I suspect it to be automated, but 1) it isn't marked as such; 2) there's no notice advising against replying and 3) my reply to that email was not rejected. So is this address a thing worth of waiting for? Brandmeister^talk 20:03, 6 June 2018 (UTC)[reply]

My guess is that "+3ncfuutagcay804" is a way for whoever is monitoring that address to track your case. Gmail will ignore the plus sign and everything after it and deliver the email as if it weren't there, which allows the user to filter emails based on the additional string [1]. I would assume Google's in-house email system works similarly. clpo13_(talk) 20:20, 6 June 2018 (UTC)[reply]

The trick with the plus sign and the label is actually broader than gmail, it's a standard defined by RFC5233, see Email_address#Subaddressing for more details. Jahoe (talk) 09:49, 8 June 2018 (UTC)[reply]

June 8

Bluetooth Issue and Voice on GPS

I am using a Samsung Galaxy J7, with the Android version 10 operating system, using Google Maps for GPS. (I know that there may be better apps for navigation. That is not this question.) What I seem to have observed is that if I have Bluetooth turned on on the smartphone, and turned off on the Chevy, there are no voice commands from navigation, only map instructions. I don’t want to turn Bluetooth on on the car, because that will use Bluetooth in place of AM/FM/satellite radio. Is the phone just sending the voice commands to the car and having them fall into a bit bucket? Is this just the way it is, or can I do something? Robert McClenon (talk) 17:01, 8 June 2018 (UTC)[reply]

List_of_most_popular_websites

Hi,

The article should include the meaning for the green and red triangles in the list. I have no clue what they mean. Thanks a lot! Ericdec85 (talk) 17:12, 8 June 2018 (UTC)[reply]

It does explain with mouseover text that green up arrow is an increase from previous ranking and red down arrow is a decrease from previous ranking. 209.149.113.5 (talk) 18:56, 8 June 2018 (UTC)[reply]

No, actually, it just says "Increase" and "Decrease" (and "Steady" for the blue dash). It doesn't say what the number means. It doesn't say if "Increase" means a change to a higher ranking or a higher-numbered (i.e. lower) ranking, and it doesn't say what the number means. I can guess but I shouldn't have to guess. As it stands, the table is using a shorthand notation appropriate for people already familiar with it, but that is not all readers. It needs an explanation in words (or a link to some other article where such notation is explained), probably at the top of the table where it talks about changes in ranking. Similarly the column headings should mention that they are showing a ranking and change. I'd do something myself but the article is semi-protected. --76.69.118.94 (talk) 22:55, 8 June 2018 (UTC)[reply]

Your question has been answered. The convention is very common, but if you wish to discuss the template or make a suggestion, you are welcome to do so at Template talk:Increase etc.--Shantavira|^{feed me} 07:00, 9 June 2018 (UTC)[reply]

Wasn't my question, but thanks. --76.69.118.94 (talk) 07:30, 9 June 2018 (UTC)[reply]

June 9

Semantic hierarchy principle?

Is there a name for the following principle in programming language design?

Each node in the abstract syntax tree should correspond to a substring of the program text, with each node's substring being disjoint from its siblings' and contained by its parent's.
The node's semantic meaning should be determined principally (if not entirely) by its substring and lookup of any names therein.

An example discouraged by this principle is the compound comparison in Inform 6: x > 3 or y means $x>\max(3,y)$ , whereas x == 3 or y means $x\in \{3,y\}$ . This makes it difficult to assign any meaningful semantics to the 3 or y AST node: it is treated as an instruction to generate code to repeatedly apply the nearby operator. (One can salvage the situation by deeming it to represent a lazy sequence over which comparisons are mapped, but having such an entity appear in place of an expression is strange since it cannot appear in any other context where an expression is allowed.) In Haskell, by contrast, one could create a saturating monad from (x >) or (x ==) and apply it to each element of a list [3,y] but that list has a fixed set of semantics independent of the tests performed on its members.

The second point is related to the idea of using context-free grammars for programming languages, but differs in two ways:

The concern is with the (human-centric) semantics of a construct, not its initial parsing.
A CFG says that what may mean some fixed thing (what may be reduced to a given non-terminal) does not depend on context, whereas #2 says that what some fixed thing means (to what a substring may be reduced) does not depend on context.

I think I've seen something written about it, maybe even on Wikipedia, but my searching has been unsuccessful. Thanks for any pointers. --Tardis (talk) 04:03, 9 June 2018 (UTC)[reply]

Is a computer whose clock drifts by about 2 seconds a day usual?

I noticed my computer's time gets about 2 seconds behind per 24 hours. I'm running Windows 7 but I assume that has more to do with the hardware. Is that usual in your experience? Could it have anything to do with the stability of the frequency of the electric grid? Thanks. Basemetal 17:14, 9 June 2018 (UTC)[reply]

This is not unusual but modern computers can synchronize their clocks via internet. It your case the synchronization does not work. Ruslik_Zero 17:45, 9 June 2018 (UTC)[reply]

It does work. It does automatically synchronize every 7 days with time.windows.com. What I meant was, it drifts between synchronizations. That was what my question was about. When I see it's drifted like that I do manually have it synchronize with the Internet time server. But is there a way to set things up so that it automatically synchronizes with the time server not every 7 days but once a day? Basemetal 18:06, 9 June 2018 (UTC)[reply]

It doesn't have to do with the timed frequency of the electric grid, but probably with the inherent frequency of a quartz crystal. In the 1960s and 1970s, in North America, time was kept using electric clocks with synchronous motors that spun at the frequency of the 60-hertz line current. This meant that it was important for the electric utility to provide line current that alternated 60 times a second, not 59 or 61 times a second, and so the utility would slow down or speed up their alternating current as needed to stay on track, presumably compared to an atomic clock maintained by the utility or to the WWV master clock. More recently quartz crystals, which have an inherent frequency, are the usual means of keeping time, in digital clocks, and in computational devices. Cell phones synchronize their clocks to the cell carrier. This enables them to reset the time automatically on crossing a time zone boundary (or on being turned back on when the airplane lands). As Ruslik notes, it appears that you, User:Basemetal, have two annoying problems. First, the quartz crystal in your computer is slow by about 2/86,400. Second, your computer is only setting itself to the Internet once a week. Robert McClenon (talk) 18:15, 9 June 2018 (UTC)[reply]

While you are correct about the basic operation of the different clocks, strict control of the electric network frequency is inherent in the way the network operates. Classical generators naturally produce AC at a frequency directly proportional to their speed of rotation. This is used to coordinate supply and demand across the grid. All generators are operating in sync. If demand exceeds supply, the frequency on the whole grid drops slightly. On the one hand, this is buffered by the rotating masses of the generators (i.e. some of the kinetic energy of the generators is temporarily tapped to make up for the lack of production), on the other hand this signal is used in a control loop to increase (or decrease, in the opposite case) production. --Stephan Schulz (talk) 18:47, 9 June 2018 (UTC)[reply]

Thank you both for these interesting facts. Basemetal 20:11, 9 June 2018 (UTC)[reply]

@Basemetal: You can configure the system to synchronize the clock more often. I have asked Google How to change the clock synchronization interval in Windows 7 and got several useful answers on the first page of hits. I'm not going to write them here, because it involves editing registry settings and any error in transcribing might render the answer useless or even harmful. Please read what Google returns, and don't hesitate to ask further questions if anything seems obscure. HTH. --CiaPan (talk) 18:29, 9 June 2018 (UTC)[reply]

Thank you CiaPan. It worked and it wasn't that difficult after all. I followed the instructions at the first Google result namely wikihow which I found the most clear and convenient. Basemetal 20:11, 9 June 2018 (UTC)[reply]

I don't know anything about Windows, but NTP-based solutions have been able to correct for a systematic clock drift since approximately the late stone age. --Stephan Schulz (talk) 18:33, 9 June 2018 (UTC)[reply]

Robert says "Cell phones synchronize their clocks to the cell carrier". What is "the cell carrier"? Is it the radio wave which connects the cellphone to the base station? If it is, how does it control the cellphone clock? 2A02:C7F:BE08:2100:D8E2:5130:CE1:BD4B (talk) 16:44, 10 June 2018 (UTC)[reply]

Carrier is another term for Mobile phone operator, the company that provides service for a phone. Cell phones regularly send and receive small signals to nearby cell phone towers, to assign the phone to the most readily available tower. SMS messages originally used that signal (which is why it was restricted to something like 140 characters) instead of the usual message. Ian.thomson (talk) 17:03, 10 June 2018 (UTC)[reply]

A personal computer usually is not late. Since NTP, the clock is synchronized. Former PCs used an dedicated clock generator which is now part of the chipset or integrated into CPU, least if the PC is a SoC. In the generation of dedicated clock generators, another 32.768 kHz quartz (crystal oscillator) was the time base of the CMOS real-time clock. This frequency can be digitally divided exact to one second. Today, You may find this small cylinder shaped plain metal quartz device (see picture, 1st item on the left). 14.x MHz is the base of the PC clock generator, 25. MHz ist the ethernet controller time base. Increasing the capacity by a soldering dot and restoring the ceramic capacitors capacity next to the 32.768 kHz quartz by heating up exceeding 120°C, also achieved by soldering during computer is turned off can slow down the PCs time base. --Hans Haase (有问题吗) 15:39, 11 June 2018 (UTC)[reply]

Steady clock drift from the xtal timebase being slightly inaccurate is easily compensated in software (hwclock command in linux, and there must be something like that in windows). You shouldn't have to use a soldering iron. There will still be some inherent variability but it should be much better than 2 sec/day. The other cause of drift is the OS sometimes not noticing timer ticks. I don't know why that happens but is a thing. 173.228.123.166 (talk) 18:36, 11 June 2018 (UTC)[reply]

Hans Haase mentions the clock part of CMOS, but I don't see mention of the battery. When the CMOS battery begins to fail, the CMOS clock will commonly run slower. When the battery completely fails, the clock will reset to Jan 1, 1970 (or an equivalent Epoch) when the computer is shut down and restarted. I feel that most people don't use old computers. I have had to replace the CMOS battery in multiple computers because I use them for so long that the batteries do fail. 209.149.113.5 (talk) 19:45, 11 June 2018 (UTC)[reply]

Our article real-time clock says:

Computers used as local time servers occasionally use GPS or ultra-low frequency digital radio transmissions broadcast by a national standards organization (i.e. a radio clock).

However "radio clock" says that the only signals used are transmitted by either shortwave or longwave radio transmitters. This is because the buffering used in digital transmission delays the signal unpredictably. The National Institute of Science and Technology says the low frequency transmissions are analogue [2]. This is confirmed in the Application Note put out by Hewlett Packard [3] (at p. 72). Is there an error in one of the articles? 86.131.233.241 (talk) 19:23, 12 June 2018 (UTC)[reply]

How do I make a file extension unrecognized again in Windows?

I had some files with an extension unknown to Windows so it asked me what program to open it with. I picked Notepad just to see what was in there. Now obviously Windows always opens files with that extension with Notepad. But I want to change that back to how it was before: I want to make that extension unrecognized back again the way it was, not change it so that it opens by default with some other installed program. Is there a way to do that? Basemetal 22:34, 9 June 2018 (UTC)[reply]

A search for "windows remove file association" yielded "7 Ways To to Remove a File Extension Association in Windows" as the top hit. The first four methods require add-ins, but the remaining ones do not. -- Tom N talk/contrib 04:30, 10 June 2018 (UTC)[reply]

Thanks but for some reason it didn't work. Even though in the Command Prompt "assoc" says file extension .foo is now associated with no program ("File association not found for extension .foo") Windows still opens it with Notepad or Wordpad or whatever program I change it too. I also opened the registry with "regedit". The file extension ".foo" was still there. I deleted it. I hope this won't cause any problem. (I'll find out I guess). And Windows still does the same thing. I'm gonna try to use the third method, namely associating it with a program I subsequently delete. We'll see if that will work. Basemetal 05:45, 10 June 2018 (UTC) It isn't necessary to delete extension ".foo" from the registry. It is enough to associate with no string and "assoc" will still say "File association not found for extension .foo". So I recreated the key and associated with no string which gives exactly the same result as before: .foo files still open with Notepad etc.[reply]

The 3rd method, namely associating file extension .foo with a program that you then delete does work. Interesting. Basemetal 06:32, 10 June 2018 (UTC)[reply]

Is there a way to play my MIDI sound module from Python in Windows?

The Python library has a module for accessing MIDI devices, namely ossaudiodev but that apparently only exists for Linux. On the other hand the Windows specific module winsound from what I can tell only deals with raw audio, not MIDI. Does the standard Windows version of Python have a module for accessing MIDI devices? If not do you know of modules developped by third parties that allow you to do that? Thanks. Basemetal 22:57, 9 June 2018 (UTC)[reply]

June 10

4K or HD?

File:4K or HD Bell Fibe TV.jpeg

Monitor info box showing standard HD resolution.

File:4K or HD Bell Fibe TV.jpeg 2.jpeg

Channel is 4K channel.

Dear Wikipedians:

I have a 4K monitor and a (supposedly) 4K cable IPTV box. I have tuned the IPTV box to a 4K channel. However, when I look at the "info" section of my monitor's menu, it still says the resolution is at standard HD 1920×1090. So I am a bit confused: is the channel I'm looking at actually playing at 4K or has it been downgraded to standard HD? I have attached two screenshots here.

Any insights would be much appreciated!

L33th4x0r (talk) 12:40, 10 June 2018 (UTC)[reply]

There are a lot of compatibility issues. The monitor may only accept 4K on a particular port. The monitory may need a special configuration setting to allow the 4K to work, and it may do so by sacrificing something else, say frame rate. The standard that the monitor uses may not be the same as what your box is putting out. Perhaps the bandwidth to the box is not actually enough to support 4K and it down-grades. WiFi often cannot provide the bandwidth, so an actual copper Ethernet connection ma be in order. Graeme Bartlett (talk) 23:49, 10 June 2018 (UTC)[reply]

June 12

Virtual "RAID 1" in flash memory by splitting into equal sections?

I would like to store a small amount of important data on some USB flash drives or microSD cards. Since parts of memory can sometimes fail and lead to loss of data, I was wondering whether there is some kind of software that makes a sort of virtual RAID 1 on a single drive by splitting it in half or even in thirds and then have two or three copies of the same data in the different sections so that if the memory should fail in one section there would be others. Of course I could just copy everthing two or three times but that's a lot more manual effort to maintain. — Preceding unsigned comment added by 185.230.100.66 (talk) 19:28, 12 June 2018 (UTC)[reply]

Christmas coming early?

If your bank receives through the post a cheque made payable to you it will ensure your name appears on it before taking the money from the sender's account. If it receives the money electronically it does not check that your name appears on the payment instruction before taking the money from the sender's account. This means that if the payee is named, for example, as "Santa Claus" you still get the money provided the sort code and account number are yours. When the payer queries the payment ("Did you credit Santa Claus as I directed?") it refuses to say whose account was credited. The payment is subject to the bank's terms and conditions. What do these terms have to say about this? 86.131.233.241 (talk) 19:38, 12 June 2018 (UTC)[reply]

Do you mind this Internet cookie? How about this one? And this one? And this one?

I'm fed up to the back teeth of websites asking my permission to put cookie on my PC. My idea to comply with the stupid cookie regulations is that there should be a browser setting whereby a user can automatically tell websites that they're fine with cookies just like they were for a decade before these rules were implemented. The website then checks this setting before asking with another intrusive message or banner. To whom do I suggest this? The World Wide Web Consortium? It requires co-operation by web designers and web browser developers. I'd preferably like it implemented about three years ago... --185.230.100.66 (talk) 22:16, 12 June 2018 (UTC)[reply]

That sounds similar to Do Not Track. W3C would probably be your best bet, since they have a hand in supporting DNT, though I don't know if there'd be much support for opting in to tracking as opposed to opting out. Advertisers would probably like it more than DNT, though. clpo13_(talk) 22:31, 12 June 2018 (UTC)[reply]

There's a bit mentioned at HTTP cookie#EU cookie directive that sounds similar to what you're suggesting; P3P would have sent privacy policy information to the browser via an HTTP header and set cookies according to the browser settings. It looks like it was never very widely supported, though. clpo13_(talk) 22:41, 12 June 2018 (UTC)[reply]

June 13

Websites detecting my mouse movements

For some time various websites have been programmed to detect when the mouse makes a quick movement to the top of the page which is assumed to be the user reaching for the tab to close it so the website responds with some obnoxious request to join their stupid newsletter or some other crap no-one in the history of the Internet has ever been in the least bit interested in. Often I'm not even trying to leave the website but I browse with many tabs open and multi-task. How do I suppress this bull**** so I never get pestered in this way again? Also can we please make it crime? --185.230.100.66 (talk) 04:39, 13 June 2018 (UTC)[reply]