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May 31

Opening laptop for cleaning and warranty

One of my fans started to do some noise when the comp is idle, it's possibly dust since I once had to service the machine for such an issue in the past. I was planning to bring it to a local computer shop, however isn't this against the warranty not having ASUS specifically repair the machine? It's an Asus Zephyrus 701. Don't really feel not having the machine for three weeks if I go the RMA route... Thank you for your input! Yes I know a layman could open and dust, but I'd rather have someone qualified. Me and manual labor... :o Raskssinger (talk) 01:19, 31 May 2020 (UTC)[reply]

Without having access to the warranty documentation that came with your specific laptop, we really couldn't say definitively. This global warranty card for most of their machines suggests that the warranty is only good for up to a year but maybe yours is different. The warranty doesn't provide an allowance for third-party repair and specifically says they won't fix any trouble caused by third-parties. "This Warranty does not include failure caused by improper installation, operation, cleaning or maintenance, accident, damage, misuse, abuse, non-ASUS modifications to the product, any third party software programs, normal wear and tear or any other event, act, default or omission outside ASUS’ control."

This owner's manual (do you have the GX701? Because that's what I'm finding results for) includes directions on how to clean it. Do NOT vacuum it. Ian.thomson (talk) 01:45, 31 May 2020 (UTC)[reply]

In the US, the Magnuson–Moss Warranty Act specifies that they cannot void your warranty for opening your case, but that anything you break is on you. Manufacturers often add "warranty void if removed" strikers on items, but that doesn't change the law. (BTW, does anyone know whether there are similar laws for the UK, EU, and/or AU/NZ)? --Guy Macon (talk) 06:17, 31 May 2020 (UTC)[reply]

To be clear none of this is legal advice.

But there isn't any requirement that manufacturers can't void your warranty in silly ways in NZ AFAIK. However the Consumer Guarantees Act provides rights for purchases of goods in a number of circumstances (e.g. pretty much any good purchased from a company in NZ except for commercial products) that cannot be contracted out of or excluded except in certain cases for transactions between businesses. This includes the requirement that goods be of "acceptable quality" and "fit for purpose". [1] [2] [3]

The general interpretation of the CGA is it covers pretty much any situation where a standard warranty applies, and more. Therefore even if your warranty is technically "void" because of some modification or whatever, your are still entitled to the same or actually greater, protections than you were offered by the warranty. Of course this doesn't stop companies trying, and many feel enforcement action against retailers is often weak [4] [5] [6] [7] [8] [9]

It's my understanding that the Australian Consumer Law was partly modeled on the law in NZ and other jurisdictions with similar laws and therefore has similar protections. [10] [11] So at a minimum, the situation there is similar i.e. even if your warranty is "void" you are likely still entitled to the same protections.

Nil Einne (talk) 14:23, 31 May 2020 (UTC)[reply]

It had better not be legal advice, as the header on this page states: Do not edit others' comments and do not give any medical or legal advice.

I live in AU, which has similar protections. I was thinking of writing about them, but the issue here (dust) doesn’t sound like it would be covered. Unless it turns out it’s not dust? Brianjd (talk) 14:28, 31 May 2020 (UTC)[reply]

I'm aware of that, I'm a strong advocate against providing legal advice on Wikipedia and have removed responses for violation the guidelines. But this and other history has shown a large number of people do not read it. Therefore I always make personal disclaimers to try and prevent misinterpretation by any readers.

I don't think anyone is suggesting that an accumulation of dust will generally be something that a manufacturer has to repair. (In some circumstances it's possible they may need to, but this wasn't the point of the discussion as I understood it.) The question is whether manufacturer can void your warranty if you open the device or bring it to a third party to clean the dust for you. Based on reading a lot on this in various sources in the past, like those I linked, my understanding is that in NZ maybe they can void your warranty in such circumstances. However they will still have to offer you pretty much the same protections even without you warranty.

Therefore if you device later develops a fault, they cannot claim that because you opened it, or got a third party to clean the dust or whatever, they don't have to repair or replace it; unless they can pinpoint how you or the third party damaged the device when doing so causing it to develop this fault. (I believe the situation in Australia is similar although this is mostly based on some very minor reading in the past, combined with the fact it's my understanding that it's similar to the CGA.)

It may not even be "later developed". If your fan is making noise, or your device is overheating, cleaning the dust yourself to try and fix the issue may very well be a reasonable first step. If it turns out this doesn't fix the problem, it may very well be an issue the manufacturer or retailer is required to remedy. If they're going to turn around and claim they don't have to because you opened it even though you didn't contribute to the problem, this is likely to be very annoying to say the least.

Nil Einne (talk) 15:13, 31 May 2020 (UTC)[reply]

Because, once again, someone posted "It had better not be legal advice, as the header on this page states: Do not give any medical or legal advice", I am, once again. posting medical and legal advice. Please note that I did not bring up the topic, but that I am allowed to respond when someone posts incorrect information to the refdesks.

There are some who believe that Wikipedia has a policy against giving medical, legal, and business advice, but no such policy or guideline exists. (If you are about to cite the reference desk guidelines, or anything in an infobox at the top of a page, please read WP:LOCALCON and then show me where the Wikipedia community approved them).

Here is some medical advice: Don't do crystal meth. It will screw up your health. Don't bother asking a doctor if crystal meth is good for you. It isn't. (medical disclaimer.)

Here is some legal advice: Don't do crystal meth. It is likely to get you arrested. Don't bother asking a lawyer if crystal meth is illegal. It is.(legal disclaimer.)

Here is some professional advice: Don't do crystal meth. It will use up all of your money and is likely to get you fired. Don't bother asking a certified financial planner if becoming a meth addict is good for your finances. It isn't. (general disclaimer.)

There. I just provided medical, legal, and professional advice, and while I did make a point, I did so without being disruptive.

Feel free to report my behavior at WP:ANI if you believe that I have violated any Wikipedia policy or guideline.

The actual rule is that context matters. If you are about to advise someone to drink bleach, that is medical advice that isn't allowed on Wikipedia. If you want to tell people not to drink bleach or to say that crystal meth is bad for your health, that is medical advice that is allowed on Wikipedia.

BTW, here is some more free advice: In my opinion food poisoning, terminal cancer and AIDS are even more effective methods of weight loss than doing crystal meth, so if you really want to shed those pounds why not try all four at the same time?^{(In case anyone missed it, that was a joke.)} More advice: don't get your medical advice from an electronics engineer. --Guy Macon (talk) 16:25, 31 May 2020 (UTC)[reply]

There is really nothing much to "dusting out" a computer. Get some gas duster (often inaccurately called "canned air") and blow it around inside. Free tip: wear gloves or wrap a towel around the can, as it will get cold due to the expanding gas. You don't want to use a vacuum, feather duster, etc., because this can cause static electricity build-up, which can damage components. If the noise persists, it's probably just the fan bearing wearing out. The fan may be user-replaceable, depending on what kind of fan it is. You will need to refer to the manual for that. (It's probably available on the ASUS website.) --47.146.63.87 (talk) 22:49, 31 May 2020 (UTC)[reply]

Oh, a tip to possibly avoid wasted time: if you haven't, assuming you're on Windows, when the noise is present, open Resource Monitor and ensure the system is actually idle (nothing churning CPU cycles in the background). Make sure you're viewing processes from all users, which requires administrator access. You could also install system monitoring software to view the internal temperatures. It's a good idea to double-check that it's not actually the system running hot before going off on a wild goose chase about fans. You should still dust out your computer periodically in any case. --47.146.63.87 (talk) 10:10, 2 June 2020 (UTC)[reply]

Perl array variable loop index

In Perl, is it possible to use an array element as the index of a for loop? NOT Can I use a variable to index an array.

Having created @ary, I have tried

for ${ary[2]} ( 1..5 ) {
   ...
}

but it won't compile.

What I actually want is

for ${ary[$ix]} ( 1..5 ) {
   ...
}

Can it be done? — Preceding unsigned comment added by SGBailey (talk • contribs) 10:42, 31 May 2020 (UTC)[reply]

I’m not familiar with Perl, but I just had a quick look at some documentation, and it looks like the answer is no. In fact, as far as I can remember, no language that I have used (C, BASIC, MATLAB, Pascal, JavaScript, Bash) allows you to do this. Brianjd (talk) 11:56, 31 May 2020 (UTC)[reply]
- My brain is obviously not working properly today. Brianjd (talk) 13:19, 31 May 2020 (UTC)[reply]
  - Of course you can use the for (initialiser; test; increment) form for C and JavaScript, at least, but that’s different to the Perl example above. So let’s look at the for...in form in JavaScript. I don’t ever remember ever seeing a loop like:
```
var x = []; var i = 0; var some_array; function do_something(){} for (x[i] in some_array) do_something(x[i]);
```
  I really expected it to fail. And the visual editor I used to type this reply didn’t like it. But it ran fine in my browser console. So perhaps it is possible in Perl too. We’ll need to investigate further. Maybe it’s time for someone else to take over. Brianjd (talk) 13:39, 31 May 2020 (UTC)[reply]
Just had a quick play with Perl and it looks like OP is right: you can’t do that. But you can use a so-called “C-style” loop:
```
for ($ary[$ix] = 1; $ary[$ix] <= 5; ++$ary[$ix]) { ... }
```

Brianjd (talk) 13:58, 31 May 2020 (UTC)[reply]

Alternatively, you can use another variable:

for my $temp ( 1..5 ) {
   /* The curly braces are unnecessary, but you included them in your example. */
   ${ary[$ix]} = $temp;
   ...
}

@SGBailey: Hopefully that answers your question. Brianjd (talk) 14:02, 31 May 2020 (UTC)[reply]

I put the curly braces in because

 for $ary[2] ( 1..5 ) {

failed and It was a wild stab to see if I could persuade perl to use an array element as the index. -- SGBailey (talk)

Thanks - I'll probably go with the extra my variable. -- SGBailey (talk) 15:09, 31 May 2020 (UTC)[reply]

As always we should keep the XY problem in mind. What are you trying to accomplish? Typically in Perl you just loop through an array directly:

for my $element (@array) { print $element, "\n"; }

If you want a subset of the array elements, the phrase people usually refer to this by is "array slice" or "slicing an array". For instance, to grab the zeroth through fourth elements (remember, numbering starts at zero):

for my $element (@array[0..4]) { print $element, "\n"; }

.. is the range operator. C-style loops with an index variable are possible but usually not necessary. If you're doing more complicated things, you can manually hack up a bunch of fancy stuff using arrayrefs and all that, but typically you just want to use a CPAN module that does what you want. Not knowing your level of Perl experience, I'll remind you to always use strict; use warnings;. If you're new to Perl this is a great tutorial. --47.146.63.87 (talk) 23:20, 31 May 2020 (UTC)[reply]

@SGBailey: You’ll probably want to check this reply too; it sounds like it was written by someone who actually knows Perl. Brianjd (talk) 01:41, 1 June 2020 (UTC)[reply]

This IS NOT what I was trying to do. THIS indexes through an array. I want to use an array element to index through something ELSE. Thanks anyway. -- SGBailey (talk) 09:18, 1 June 2020 (UTC)[reply]

@SGBailey: Everyone understands this already. That’s exactly the point. You are trying to do something weird, and we want to know why. Perhaps you don’t need to use an array element to index through another array to begin with. Brianjd (talk) 11:55, 1 June 2020 (UTC)[reply]

Yeah, I'm scratching my head as to why you'd want to do this. Why do you need to index into an array to begin with, and why is the index inside another array? I mean, in a sense it's not wrong as long as it works, but I suspect there's a better way to do what you want to do. What's in these arrays? One guess I have is you're trying to duct-tape together a more complex data structure, like a multidimensional array. If you can show code context, we can probably give better suggestions. I'm not sure I'd quite call myself a Perl expert, but I have some experience. --47.146.63.87 (talk) 15:04, 1 June 2020 (UTC)[reply]

XY problem question aside, I'd love to hear from a perl guru about the precise mechanics which prevent an array element from being used as the variable of a foreach loop. My hunch is that it is due to scoping issues. See https://perldoc.perl.org/perlsyn.html#Foreach-Loops :

If the variable is preceded with the keyword my, then it is lexically scoped, and is therefore visible only within the loop. Otherwise, the variable is implicitly local to the loop and regains its former value upon exiting the loop.

I suspect either scoping mechanism breaks (at least as it is applied in a foreach loop) when applied to a specific array element, much as how my @a = (5); works, but my $a[0] = 5; generates a syntax error. Arguing against this is that the explicitly local local $a[0] = 5; does work, hence my parenthetical. -- ToE 20:13, 1 June 2020 (UTC)[reply]

It's because it's a syntax error. In for VAR EXPR, VAR has to be a scalar variable. It says that somewhere on that page but I don't blame you for not seeing it; the official Perl docs are a bit of a hot mess. In $array[0], array is an array variable even though you're telling Perl to evaluate it in scalar context; if you use that as an l-value (which is what's done in for VAR) it assigns to the zeroth element of array. This is why my @array = (0..2); my $array = 'foo'; print $array[0], $array; is legal. Scalar and array variables "live separately" and don't collide, and the scalarness/arrayness of a variable is permanent. (That's why you have to specify that with $/@ when declaring.) --47.146.63.87 (talk) 22:21, 1 June 2020 (UTC)[reply]

Oh also, want to know why local $a[0] = 5; in your example works? Unless you're familiar with Perl I guarantee it's not doing what you think. Deep breath: it declares a new global array a and assigns 5 to the zeroth element. Yes, global. Look at the doc for the local function. local takes any expression as argument. It evaluates to just $a[0] = 5;. This is a syntax error under strict, which is why you want to always use it for "serious" code unless you're insane. (Add use strict; and see. It will give a compile error.) Compare this (no strict): $a = 'foo'; { local $a = 5; print $a;} print $a;. Within the block, a new a is declared with local scope, which shadows the global a. my $a[0] = 5; is illegal because my has different syntax: my (TYPE) VARLIST (: ATTRS) where stuff in () is optional. So it tries to declare a scalar a but then assign to it as an array, which is illegal. --47.146.63.87 (talk) 01:43, 2 June 2020 (UTC)[reply]

Self-correction on re-reading: local $a[0] = 5; actually doesn't declare. It just assigns. Without strict, variables are auto-instantiated when first referred to if they haven't been instantiated. That's why it works; Perl goes to assign to a[0], sees that the array a doesn't exist, creates it silently, and then assigns to the zeroth element. A VARLIST only allows assignment-on-instantiation, which is why it errors. Sorry, that would have confused you if you closely followed my wording. --47.146.63.87 (talk) 04:18, 2 June 2020 (UTC)[reply]

While on wording, I'd nitpick your earlier "array ... in scalar context", as that is not the proper terminology to describe an array element, but is instead used to describe exactly what it says. An array in a scalar context returns the number of elements in the array whether the scalar context is forced, as in print scalar @a;, or natural, as in while(@a){print pop @a;}.

Yes, the my $a[0] = 5; syntax error is largely a red herring. Thanks.

And yes, as perldoc local says, You really probably want to be using my instead, because local isn't what most people think of as "local". Though I am confused as to why local's syntax is local EXPR an not local VARLIST in parallel with my, but I don't recall ever needing to use local in the limited Perl I've coded.

And I do agree that the simplest answer to SGB's question is: No, it is not permitted because it violates the syntax which calls for:

LABEL for VAR (LIST) BLOCK

where VAR is a scalar variable.

But more can be said about why the foreach syntax requires a scalar variable instead of also permitting scalar l-values such as array and hash elements. That wouldn't be a particularly useful feature, but it isn't as if the perl compiler was written to exclude the possibility of doing things in unusual and sometimes bizarre ways. And I think a clue lies in the scoping of VAR. This:

$a = 7;
for $a (1..3) { "RANDOM CODE HERE" }
print $a;

prints 7, and no amount of expressed scoping via braces or my or local is going to get it to print 3. The foreach VAR is always local to the foreach itself, so if somehow an array element could be used for that purpose, it would have no relation to an identically named array instantiated outside the foreach, and the foreach's block couldn't access that earlier array. My suspicion is that the foreach VAR may not even be instantiated in the stanadard way a scalar variable is, but I've never looked under the hood. -- ToE 15:25, 2 June 2020 (UTC)[reply]

You're correct; I worded that wrong. The Perl tutorial I linked earlier explains it well: the value stored in the array element is a scalar. my was added in Perl 5. I suspect that's why the syntax differs, since I believe my was added to facilitate more sane and structured programming. (There are a lot of horrors in circa-'90s Perl code from before "always use strict" became widely accepted in the Perl community.) One common neat little trick is using something like local $/; in a block to temporarily change the input field separator, which lets you easily do things like slurp a whole file into a variable. See perlvar for examples. I think you're probably right about how the interpreter handles loop variables. My guess is it's simpler and more efficient to just decree that only scalars are allowed. That means Perl can just verify that at compile time and the interpreter code for loop constructs can just assume it's assigning to a scalar. --47.146.63.87 (talk) 03:22, 3 June 2020 (UTC)[reply]

Thanks, and thanks for your above linking of "Learn Perl in about 2 hours 30 minutes". -- ToE 10:19, 3 June 2020 (UTC)[reply]

No problem. #perl on Freenode is a good place for Perl beginners. The qntm tutorial is one linked from their associated list of tutorials. --47.146.63.87 (talk) 23:58, 3 June 2020 (UTC)[reply]

Video editing

Hi! What software can be used to make a video with moving pictures like this: https://www.youtube.com/watch?v=305OOQGc2yY. Thanks! 1.55.250.61 (talk) 19:33, 31 May 2020 (UTC)[reply]

Note: I have repaired the broken link. You could not post it here because of our "shortener blacklist" which denies the youtu.be domain name. youtube.com works fine. Elizium23 (talk) 23:02, 31 May 2020 (UTC)[reply]

June 1

Acrobat Reader DC problem, again

I asked this about six weeks ago. I am trying to use Adobe Acrobat Reader DC to read and print PDF files. As is often the case here, someone told me that I was conflating Adobe Acrobat with Adobe Acrobat Reader, and that I needed to specify what I was trying to do with them so that they would know what to lecture me about. Another editor, properly, lectured them back for not having seen that I had already answered that I was trying to use the most current version of the Reader to view and print PDF files. Here, again, is the problem. I have installed Adobe Acrobat Reader DC from the Adobe web site. After a while, something happens so that when I launch a PDF, or when I click on the icon for Adobe Acrobat Reader DC on the desktop, Adobe Acrobat Reader opens as a Background Process. That is, the Task Manager thing lists it as a Background Process. This means that I can't do anything with it. I know an answer, which is that I can uninstall it, and re-install it from the Adobe web site, and then it runs as an App in foreground, for a while. Then it gets into being a background process again. So the question is what should I do, other than re-install it maybe once a week.

My first thought was to call Adobe technical support. Unless I have misread something, they won't take technical support calls for something that I didn't pay for.

I could install Adobe Acrobat full-up on a trial basis, but I know that when the trial period is over, I don't want to pay for it.

Is there either an alternate freeware program or a low-cost program that I can install as an alternative to Adobe Acrobat Reader DC?

Does someone have a suggestion as to what may be causing this to happen and what to do about it?

Robert McClenon (talk) 02:48, 1 June 2020 (UTC)[reply]

What OS are you running and what sort of machine? There's plenty of alternatives for Linux boxes and there seem to be a fair few for Android phones. If you're stuck with Windows pre-10 I can't help, but fully updated Win10 has the ability to run native Linux images. So far I've only run a few tests using BASH but it is looking good. You can either start BASH directly, or else load up an Ubuntu window. Don't know how full the provision is, but it's worth a coffee break fiddling. Martin of Sheffield (talk) 08:35, 1 June 2020 (UTC)[reply]

I suggest you take a look at List of PDF software. FWIW I use Sumatra PDF.--Shantavira|^{feed me} 10:15, 1 June 2020 (UTC)[reply]

+1 for SumatraPDF. If it doesn't suit your needs you can try Foxit Reader but I'd suggest Sumatra first since it's very lightweight and won't have this kind of problem. 93.136.103.94 (talk) 10:57, 1 June 2020 (UTC)[reply]

This sounds like some kind of odd problem with your machine and not Acrobat Reader specifically. I have never had this occur on any Windows 10 machine I've used Acrobat Reader on. Does this happen with any other programs that you've noticed?

Mozilla Firefox, Google Chrome, and probably some other web browsers now can open PDFs themselves and have been able to for several years. This includes PDFs saved on your machine. To open one, just open the file in the browser; do a Web search for, for instance, "firefox open file" if you're not sure how. If you want, you can make your preferred browser the default for opening PDFs, which means it will be used for things like opening them when double-clicked in File Explorer. For this, Web search "windows 10 default." --47.146.63.87 (talk) 15:17, 1 June 2020 (UTC)[reply]

Microsoft Edge can also open PDF files. Brianjd (talk) 15:21, 1 June 2020 (UTC)[reply]

Oh, one thing to note is that once in a while the browser PDF readers will have trouble with a PDF, and they also don't support the fancy extra features that Acrobat has, such as filling in form fields. Acrobat is basically the only thing that fully supports every single feature of PDF in all of the format's terrifyingly gory detail. The browser PDF readers are intended as "good enough" basic readers. --47.146.63.87 (talk) 15:51, 1 June 2020 (UTC)[reply]

We know from an earlier question that the OP is using Windows 10. If you run Windows 10, expect odd problems with your machine becuase of those updates Microsoft keeps forcing on everyone. (By the way, if you already have an odd problem with your machine, trying to back up the whole machine now might be a bad idea.) Brianjd (talk) 15:24, 1 June 2020 (UTC)[reply]

+1 to that too (regrettably, as a 20+ years Windows ex-user). If you really need Windows 10, you should try getting your hands on an Entreprise edition if you can, I heard they're more stable. 93.136.103.94 (talk) 19:21, 1 June 2020 (UTC)[reply]

In my personal experience I've had no real issues with Windows 10 Home/Business. One thing I do is always wait a bit before installing Windows updates rather than install them immediately (usually on Patch Tuesday) which generally means any problematic updates get reverted or fixed beforehand. Fortunately this is easy now in recent Windows 10 versions as you can temporarily pause Windows updates. In general this is good practice for any software unless you're fine with being a quasi-beta tester, unless it's software that gets well-tested before official release. (For example, stable Firefox releases are usually fine, because testing is done beforehand in the unstable and nightly branches.) --47.146.63.87 (talk) 02:27, 5 June 2020 (UTC)[reply]

Restarting Windows

My problem, or perhaps symptom, was that Acrobat was loading as a background process, and then it can't be switched to in foreground, and so doesn't view and print. That's a problem. So I restarted Windows. Then I restarted Acrobat Reader DC by launching a PDF. The PDF launches fine and prints. This provides a constraint on what the problem has been. There wasn't anything wrong with the way Acrobat was installed. So there was something wrong with the way Windows and Acrobat were interacting. My guess is that there was some sort of a leftover of Acrobat, similar to having a zombie process in Unix. I might still look for an alternate PDF viewer, but the problem isn't with Acrobat as such, but with Windows getting a dislike to Acrobat. Robert McClenon (talk) 19:14, 1 June 2020 (UTC)[reply]

Is your Acrobat Reader a Windows Store app? That sort of thing is known to cause problems in Windows 10. Alternatively, Acrobat Reader depends on some kind of background process (supposedly used for quicker startup) which starts with your computer and idles in the background even after you close the Reader (tho you can safely kill it in Task Manager), this could be contributing to the problem. In addition, SumatraPDF has a simpler PDF renderer (MuPDF) so it isn't as prone to bugs and security holes as Acrobat (it doesn't do forms and JavaScript), might be worth installing simply on that basis. However you're correct in what you wrote here. 93.136.103.94 (talk) 19:21, 1 June 2020 (UTC)[reply]

I found [12] [13] which suggest this has been a long standing problem with Adobe Reader for some people. Windows updates have fixed it (rather than created it) for some. However there's no clear resolution. You can try using Adobe's cleaner tools and reinstalling but it doesn't sound like that works for everyone. It seems for most or all people who have reported this problem, running Adobe Reader in a different user account appears to resolve it suggesting whatever the problem is, there's some interaction with something in the user account.

But I also found this [14] which is interesting. I'm guessing your not running Total Commander? But are you running anything with admin privileges which you are using to open PDFs? I do hope you're not running any browser with admin privileges but maybe if you are or something else e.g. PowerShell, Cmd, some file manager, some phone transfer utility, some backup tool, and using it to open Adobe Reader probably via trying to open a PDF, that's likely the cause of your problems. Note that if you install something and then run it from the install option, this sometimes results with the program running with admin privileges (until you quit it). Likewise, I'd avoid trying to open PDFs from any installer just in case.

Also, although as mentioned by one of the forum posters, disabling the protected mode in Adobe Reader [15] [16] may resolve the problem, I strongly recommend against it. As some of the earlier answers have attested to, modern PDFs can be very complicated beasts with scripting and other such stuff which means a lot of complicated code in the reader and so a lot of attack surfaces. The protected mode in Adobe Reader is there for a reason.

If this doesn't help, while not a solution per se, some of the forum threads mentioned something I think you missed. Unless you're running with extremely restricted privileges with no possibility of elevation, or maybe some weird thing like Windows S, AFAIK it's not true you cannot do anything to background processes. You should still still be able to end task/kill them. I suspect, especially given you've now confirmed restarting fixes it, you'll find that killing all Adobe Reader processes or if that fails, all Adobe processes will resolve the problem without requiring a restart.

Nil Einne (talk) 18:11, 3 June 2020 (UTC)[reply]

AMOLED for PCs

For some years now we've had AMOLED screens on cell phones, which have true blacks since pixel brightness can be apparently continuously toned down to zero - unlike usual LCD screens which still emit glow even at full black with darkest possible settings. Why don't we have AMOLEDs for computer screens? If we do what are they called / why am I only finding cellphones? Thx 93.136.103.94 (talk) 10:55, 1 June 2020 (UTC)[reply]

What about just OLED? I don't believe the active-matrix part is necessary for the "blacker blacks" feature you want. I found a $3,999 OLED monitor on Newegg. Elizium23 (talk) 11:00, 1 June 2020 (UTC)[reply]

As mentioned, AMOLED is OLED. The AM part refers to the layer that charges the pixels, not the light producing diodes. AMOLED is popular in handheld devices because it can use less power under common handheld circumstances (the colors don't change a lot) and the backplane tends to be more flexible than a standard OLED. So, are you asking about OLED (and AMOLED) monitors or are you specifically looking for an AMOLED backplane on a monitor? Both exist. They aren't the chep monitors, so they won't turn up in the first few pages of a monitor list if you sort by price. Some places won't even sell them because they only deal in cheap equipment. There is a catch though. From the television world, it was discovered that AMOLED is more prone to burn-in than OLED. The "store-n-charge" backplane is the issue, not the light emitting diodes. Computer usage will make burn-in events more frequent. The technology to fight burn-in is not cheap. So, to jump from OLED to AMOLED in a computer display is going to be more expensive. Some gamers want it. They are using AMOLED televisions as gaming monitors. The market is there, but it is very tiny. That is why you will find very few offerings in AMOLED that are strictly computer monitors. But, they do exist. Now, I need caffeine. I've forgotten the question three separate times in attempting to write this response. 97.82.165.112 (talk) 11:34, 1 June 2020 (UTC)[reply]

Screensavers are coming back, baby! (Though typically you can just have the display "sleep" automatically which is better to save power.) --47.146.63.87 (talk) 15:41, 1 June 2020 (UTC)[reply]

Well I just want a screen where pixel brightness goes down to zero so it can be comfortably used in a pitch dark room without eye irritation. Is OLED enough for this? While power consumption (and refresh rate, etc.) doesn't matter to me, $4k sounds like far too much for my budget. Is there something non-Dell in the several hundo range? ;) 93.136.103.94 (talk) 19:12, 1 June 2020 (UTC)[reply]

The Panasonic Toughbook 55 laptop[17] can set the screen brightness low enough to be just barely readable in total darkness, even lower so that it is completely dark unless you are wearing night vision goggles, or bright enough to be easily readable in direct sunlight. So it can be done, but the Panasonic Toughbook 55 is a specialized piece of equipment designed for use on the battlefield or in police cars, and thus is quite expensive. I know of no regular monitor that can do that. You could try a layer or two of this: [ https://www.amazon.com/dp/B07W7LB5XC/ ]. --Guy Macon (talk) 22:10, 1 June 2020 (UTC)[reply]

There is not much difference these days between "televisions" and "monitors" since fundamentally they're the same thing. (I have noticed the term "display" seems to be becoming more popular as a catch-all term, probably for this reason.) The difference is mostly features and the housing, as "televisions" are often mounted on a wall or mount. DVI, HDMI, and DisplayPort are all interchangeable with the appropriate cables/adapters. Even a VGA connector can be hooked into any of those, though it may require an analog-to-digital converter if the computer's graphics controller can't be configured to put digital output on the VGA connector rather than analog. (Some "televisions" have a VGA input though these are becoming rarer so I'm not sure too many AMOLED TVs will have them.) --47.146.63.87 (talk) 15:41, 1 June 2020 (UTC)[reply]

I don't know about VGA but my TVs have SCART. They're several years old tho. 93.136.103.94 (talk) 19:12, 1 June 2020 (UTC)[reply]

SCART is unheard-of this side of the pond. Here TVs use RCA connectors for analog non-tuner input, or the mini-DIN for S-Video. Until the 2000s PCs near-universally used the VGA connector for video output which means fancier TVs often had a VGA input, as did things like projectors. Some still do but it's becoming less common as PCs have mostly phased-out VGA. --47.146.63.87 (talk) 09:53, 2 June 2020 (UTC)[reply]

While the overall packages are becoming very similar, televisions are designed for quick changes while monitors are designed for crisp definition. It is possible to see the difference if you know what you are looking for. If I watch a movie on a computer monitor and it pans left or right, I can see the stutter on my computer monitor. Similarly, if I display a presentation on my television, I can see the fuzz around the edges if the letters. For almost all purposes though, you can display HDMI out to nearly all modern monitors and televisions and it will be satisfactory. 97.82.165.112 (talk) 22:39, 1 June 2020 (UTC)[reply]

Right, I didn't want to get into the weeds. They tend to be optimized for different things, but I think a lot of users don't care much. Those who care are gamers, cinephiles, etc. who pay close attention to things like refresh rate. --47.146.63.87 (talk) 09:53, 2 June 2020 (UTC)[reply]

June 4

Challenge

Challenge: can anyone make the following image smaller than 724 bytes and still be a valid PNG file?
(Used on User:Example#Example image.)

How small can you make it using JPG, GIF, or any other format?
--Guy Macon (talk) 04:52, 4 June 2020 (UTC)[reply]

"Any other format" opened up for me the fun puzzle of "describe these color bars as tersely as possible." Is there a file format, somehow solely in love with rectangles, whose only data is (x1, y1), (x2, y2) (color)? --jpgordon^{𝄢𝄆 𝄐𝄇} 06:53, 4 June 2020 (UTC)[reply]

Jpgordon, there should be no reason you couldn't SVG this and make it very tiny. I don't know what that format's overhead is, but yeah, its contents would basically be what you describe. Elizium23 (talk) 07:20, 4 June 2020 (UTC)[reply]

It has 22 rectangles, and you have 32 bytes to define each one. (33 would make it 2 bytes bigger than the existing PNG.)

You can define an X/Y inside of 500X500 image with 18 bits. I would be happy with 256x256, 512x512, or any other size if the byte count was lower, so lets assume each rectangle gets 1 byte to define the X and one byte to define the Y of one corner and 2 bytes for the opposite corner. 4 bytes x 22 rectangles = 88 bytes to define the rectangles. (176 bytes if the format makes you define 4 corners instead of 2).

If you use 2 bytes for each of the RGB colors that's 6 x 22 = 132 bytes. Or would 1 byte per color be enough? those blacks are pretty close to each other...

132 + 88 bytes = 220 bytes, so in theory you could define a 256x256 version using 70% fewer bytes than the 724 bytes I used for the PNG.

Note: by law every online computation must have at least one stupid math error and two typos, so check those numbers yourself. --Guy Macon (talk) 08:15, 4 June 2020 (UTC)[reply]

Here is an example svg rectangle from [ https://www.w3schools.com/graphics/svg_rect.asp ]:

 <svg width="400" height="110">
   <rect width="300" height="100" style="fill:rgb(0,0,255);stroke-width:3;stroke:rgb(0,0,0)" />
 </svg>

Here is an example svg rectangle from [ http://tutorials.jenkov.com/svg/rect-element.html ]:

 <svg xmlns="http://www.w3.org/2000/svg"
      xmlns:xlink="http://www.w3.org/1999/xlink">
 
     <rect x="10" y="10" height="100" width="100"
         style="stroke:#006600; fill: #00cc00"/>
 
 </svg>

So that answers my color depth question: 1 byte per color, not 2.

Alas, that looks like it will never meet the 32 byte minimum.

--Guy Macon (talk) 08:32, 4 June 2020 (UTC)[reply]

Here it is in EPS format (713 bytes):

%!PS-Adobe-3.0 EPSF-3.0
%%BoundingBox 0 0 12 12
/q{def}def/a{bind q}bind q/b{3{255 div 3 1 roll}repeat setrgbcolor}a/c{19 19 19 
b}a/d{r r r b}a/e{r r 0 b}a/f{0 r r b}a/g{0 r 0 b}a/h{r 0 r b}a/i{r 0 0 b}a/j{0 
0 r b}a/k{0 33 78 b}a/l{1 setgray}a/m{50 0 106 b}a/n{9 9 9 b}a/o{21 21 21 b}a/p 
12 7 div q/r 192 q/s 15 7 div q/t 12 21 div q/A{moveto}a/B{lineto}a/G{p 
D}q/F{translate}q/C{B closepath fill}a/D{0 F}a/E{grestore 0 exch F gsave}a/w{0 
0 A p 0 B p 8 B 0 8 C}a/x{0 0 A p 0 B p 1 B 0 1 C}a/y{0 0 A s 0 B s 3 B 0 3 
C}a/z{0 0 A t 0 B t 3 B 0 3 C} a c 0 0 A 12 0 B 12 12 B 0 12 C
gsave k y s D l y s D m y s D s D n z t D t D o z
3 E i x G G h x G G f x G G d x 
1 E d w G e w G f w G g w G h w G i w G j w 
showpage

I made it 12 by 12 points, as EPS doesn't use pixels anyway. PiusImpavidus (talk) 11:02, 4 June 2020 (UTC)[reply]

It's a little bit of a cheat - but ... I mean, it's not really a cheat - there's a lot of really well-known theory behind self-compressibility, and a lot of quibbling about whether or not the size of the required interpreter has to count against the size of the compressed data stream,...

...but because you've asked for a very standard image, it can be compressed into a simple command to the display- or camera- hardware that generates the image.

For example, most OmniVision Image Sensors contain logic to produce this image using only a few bytes. The magic bytes, 0x70 0x80 yield the colorbar output, at least on the OVT7670. (Other models have other magic-byte sequences).

So - we can encode the SMTPE color bars in just two bytes - as long as we have the right hardware to read those bytes!

And if you're unsatisfied with the amount of compression, all we have to do is compare the size of the digital-logic-device that can run the executable program that decompresses the SVG or PNG or JPG file, and contrast the size of the digital-logic-device on the image-sensor die that is capable of interpreting the two bytes of image sensor control registers... one is, of course, a general-purpose scheme, and the other is a special-case - but that kind of generality wasn't a criteria in our OP's original statement, which specifically used the phrase "any other format" !

I'd be remiss if we didn't direct our readers to our general articles on the mathematics of lossless compression and its limitations...

Nimur (talk) 17:18, 4 June 2020 (UTC)[reply]

Yorkshireman #1:[18] Two bytes? I WISH we had two bytes! When I was a child we used a one bit configuration file to tell the generator whether to generate the image.

Yorkshireman #2: One bit? You were lucky! We had to autostart the image generator, look for a configuration file, and run it if it was zero bytes long.

Yorkshireman #3: Our autorunning image generator would exit if the configuration file existed and would generate it only if it was missing. But we were happy.

Yorkshireman #4: (Pauses) Right then. We had to go back in time look to see if the configuration file ever existed, and if it didn't, generate an image with a size of negative 765 bytes in negative 4.3 seconds using only a system with negative RAM and a negative clock speed. But try to tell the younger generation that. They won't believe you!

Enough silliness. I want an image, of any size but 500x500 or 512x512 preferred, that can be uploaded to commons and then displayed on a Wikipedia page using a normal browser. --Guy Macon (talk) 05:21, 6 June 2020 (UTC)[reply]

Ayup what's this? Four southerners being quoted by a colonist? Martin of Sheffield (talk) 08:59, 6 June 2020 (UTC)[reply]

A Dumb C# Question

Hi!

I'm here asking how do method names work? I'm using Unity with C#, and I'm relatively new. I have only used things like "Public Void Awake" or something like that, but I have seen people using things like "Public Inventory" for their method names. I'm not really asking for any answer but really just more reading material on the subject.

Thanks! JazzClam (talk) 12:22, 4 June 2020 (UTC)[reply]

It is access-type return-type method-name(param-type-1 param-name-1 [, param-type-2 param-name-2…])

so 'Inventory' is a class declared somewhere. LongHairedFop (talk) 17:04, 5 June 2020 (UTC)[reply]

Yeah, that method is returning an object of type Inventory. Inventory will be a class declared somewhere. Given it's something using Unity, it's presumably a class that implements a character's inventory. This is basic object-oriented programming stuff. Sounds like you're new to it, which is great! If you want to learn C#, you will likely find it worthwhile to invest in a good book. Unfortunately I don't really have C# experience so I'm afraid I can't recommend any off the top of my head. Perhaps some others can chime in. I do have a good deal of C++ experience, which is a similar-but-not-identical language. --47.146.63.87 (talk) 21:11, 5 June 2020 (UTC)[reply]

June 6

change current keyboard layout via a .bat file

Hi, I got a windows 10 with 2 keyboard layout. I would like to switch progrmatically the current used keyboard via a bat file. Does anyone know what command does it?--Exx8 (talk) 10:02, 6 June 2020 (UTC)[reply]

Exx8, let me Google that for you... Does this help? Elizium23 (talk) 13:05, 6 June 2020 (UTC)[reply]

That's PowerShell, which is not the traditional batch file. Now with that said, PowerShell is what you want to use because I don't think you can switch keyboard layout from Command Prompt. In a nut-power-shell (*snort*) PowerShell is the modern "replacement" for the antiquated, deprecated Command Prompt; it's intended to provide a powerful command line environment for Windows similar to Unix shells. So yeah. For extra fun, combine with AutoHotkey. Then you can bind that PowerShell script to a key combo of your choice and switch layouts by just inputting the combo. --47.146.63.87 (talk) 17:20, 6 June 2020 (UTC)[reply]

Images greyed out on iPad Mini

After years reading and editing articles on my iPad Mini, just in last several days article images became grey boxes the size of the article images with instructions at the top, and inside, of each box to tap to see the image. Tiresome and takes away from reading to continually tap to see images. Have cleared browser just in case and checked all my settings but, as I wrote, have never had this problem before. Have always used Safari w/ Google as search engine in Private mode (which I have used for years, also). Noticed on other Wikipedia forums just recently the same problem has been written about w/o an answer. Could this be a Wikipedia programming change/problem? Any thoughts/answer? Thanks Quaerens-veritatem (talk) 16:56, 6 June 2020 (UTC)[reply]

Quaerens-veritatem, are you talking about WIkipedia? Do you use the Desktop or Mobile view? Elizium23 (talk) 17:07, 6 June 2020 (UTC)[reply]

Hi Elizium23 Yes, Wikipedia. Using the Mobile view (usually use it unless adding citations). On Desktop all is well, but in Mobile have the problem, which have never had for years using Mobile.Quaerens-veritatem (talk) 17:22, 6 June 2020 (UTC)[reply]

Elizium23 I just turned off Javascript and the images came back; however, this is weird because I’ve always had Javascript enabled. I wonder if this is a change in format by Wikipedia. I don’t want to disable Javascript for the usual reasons. Any thoughts?Quaerens-veritatem (talk) 17:56, 6 June 2020 (UTC)[reply]

I don't know. Can you provide links to where this has previously been discussed? Why did you choose to post here on the Reference Desk, rather than a Wikipedia-internal page like WP:VPT? Elizium23 (talk) 17:58, 6 June 2020 (UTC)[reply]

I don’t remember, just that the same issue was posted without anyone responding. I hit the desk as I was searching around and noticed a computer reference so thought that would be a source. I’ll try WP:VPT.Quaerens-veritatem (talk) 18:46, 6 June 2020 (UTC)[reply]

Icon-to-English dictionary?

Is there an icon-to-English dictionary for those of us who are not digital natives? For example, apparently people are expected to "just know" that the five-pointed star symbol means "bookmark this Web page", that is, add it to a list of URL's which a Web browser will "remember" for you. What I am looking for is a page which allows you to look up an icon -- in the case of my example, a five-pointed star -- and get the English meaning -- in this case, add to a list of "bookmarked" Web pages. — Preceding unsigned comment added by 2602:252:D14:F900:AD98:48A0:5E0A:9FEE (talk) 18:48, 6 June 2020 (UTC)[reply]

Oh, is that what that one means? Thanks. --76.71.5.208 (talk) 19:47, 6 June 2020 (UTC)[reply]

rsync question

I often back my Fedora Linux file system up with rsync. This question came to my mind:

I have three different picture files, let's call them img1.jpg, img2.jpg and img3.jpg. Of these three, the time stamp of img3.jpg is the oldest.

I make changes to img1.jpg and img2.jpg, and after this find out that the pictures have become small enough to fit on a single picture. So I combine them to img1.jpg and delete img2.jpg as redundant. To have the numbering remain consecutive, I then move img3.jpg to img2.jpg.

After I have finished making changes, I run rsync with the --delete option.

Is the following then what happens?

rsync quite nicely updates img1.jpg on the destination. However, it finds out that the time stamp of img2.jpg is newer on the destination, so it doesn't update that file. Finally, it blissfully deletes img3.jpg from the destination as it doesn't exist on the source any more. The contents of img3.jpg have now disappeared from the destination entirely.

Would it really work like that or is rsync somehow smart enough to avoid this or go around it? JIP | Talk 20:30, 6 June 2020 (UTC)[reply]

rsync § Algorithm: The article happens to describe this, so conveniently I didn't even have to go to the docs. If the new img2.jpg has a different size (which is very likely) it will get synced. For extra safety use --checksum, which is slower but essentially guarantees every changed file is updated by generating and comparing checksums. --47.146.63.87 (talk) 20:49, 6 June 2020 (UTC)[reply]

So it is smart enough. Thanks! JIP | Talk 20:55, 6 June 2020 (UTC)[reply]

June 7

Windows 10 don't have proper shut down?

Windows 10 don't have proper shut down? I installed this OS on my computer Ram nareshji (talk) 06:15, 7 June 2020 (UTC)[reply]