Can not fix wrong answer to protected question

Question: I have discovered an answered question with a wrong answer. I've found it initially googling by myself to an answer to it, and I've fixed it. Also I've tried to do what an answer suggests - and it is NOT working. I've posted my working answer as a comment - how can I add my correct answer, so other googling people won't be misguided by wrong answer accepted?
Answer: You have an account with 101 rep on the main site.  The "protected" banner says:

This question is protected to prevent "thanks!", "me too!", or spam answers by new users. To answer it, you must have earned at least 10 reputation on this site.

However, there is a subtlety here in the wording, "earned".  The 100 bonus you receive for being a member elsewhere on Stack Exchange doesn't count in this instance:

Who can answer a protected question?
Users with 10 or more reputation can answer a protected question. However, the +100 account association bonus is ignored for this check, so you must have earned 10 or more reputation on that specific site to answer a protected question.

Since you don't have that, the "protected" restriction applies to you.  You then have a couple of options:

Be satisfied with the comment you left; in my opinion in this case that's sufficient.  The comment is clear and at the top (except for one brief thing above it). Anyone who reads the answer will see it.  The person who wrote the answer is not active here anymore, but s/he is active on S.O. so would have received notification of your comment by now.

Post your own question and provide your own answer -- if you do this, be sure to differentiate it somehow from this one.  E.g., you've implied that the documentation itself in this configuration file is wrong. Is it still the same on Jessie? I could not find this file in that location on a current Jessie lite image, so I can't say, but it seems something has changed.  I checked on another site where I have the same 101 rep and there is the "Answer your own question" tickbox at the bottom of the "Ask Question" page, these are encouraged (presuming you make good use of the mechanism).

Since this is a gray area cross-over topic with Unix & Linux, which has a much larger user base and available expertise on this kind of issue, you could ask about it there.  Hopefully, the issue would then be definitively settled, and you could add another comment with a link to that question, which would be more likely to attract the OP's attention and that of the general reader (particularly someone who's looking for a solution to a problem).

Note that you cannot edit other people's posts arbitrarily without approval until you have 2000 rep.  However, editing a wrong answer to say "EDIT: This is wrong", or (worse) to substantially change the content because you think it is wrong is absolutely inappropriate regardless of reputation.  You use comments or you add your own answer, in which you are free to reference other existing answers you believe are wrong.
You can also use flags if you believe something deserves moderator attention, and in extreme cases, feel free to access the chat, where currently there is pretty much always one mod or another lurking around whom you can ping for attention.
Comment: thanks, I've already downvoted it, actually it does not give me to downvote(it changes for a second from 7 to 6 but turns back), I've posted the right solution as a comment from the very beginning, now I've flagged it, I hope it helps
Comment: Keep in mind there's a canned response we can/should use, something like "Flags are not to be used for altogether wrong answers".  That's not how the site works.  Rightness and wrongness are not dictated by moderator fiat.  All you can do is leave your opinion and cross your fingers, it is up to the author. BTW I believe the problem w/ that answer may have to do with a change that was made with Raspbian jessie, notice that answer is 2013.
Comment: actually, I've checked it - it's completely DHCPD-dependent, so under FreeBSD it works the same way, checked it too. A part of it's grounds is [at the official Git source](https://source.isc.org/cgi-bin/gitweb.cgi?p=dhcp.git;a=blob;f=server/dhcpd.conf.example;h=5eab9516d4fe7700ce57b6a832af96a1704d4d28;hb=HEAD) : "# No service will be given on this subnet, but declaring it helps the
  25 # DHCP server to understand the network topology.
  26
  27 subnet 10.152.187.0 netmask 255.255.255.0 {
  28 }"
Comment: I always disable it and just use `dhclient`, so I am ignorant regarding this particular labyrinth.
Comment: it's a server, so if you need to *obtain* IP address from a router - you're correct in disabling it. I'm using it to give IP addresses to my hostapd-based Wi-Fi network. And this time it was a problem with config file. It took me a while to investigate it to it's source, and it is just about NOT comparing networks, but defining them ALL in `dhcpd.conf` : every network must have it's own corresponding subnet clause
Comment: Sounds like you should post an answer...
Comment: but the question is "write-protected" =( That's why I've started this question on Meta
Comment: Scroll to the bottom of the page.  There is an answer box.  Write your answer.  Click "Post Your Answer" when you are satisfied.  If that's really not there, let me know and I'll investigate.
Comment: Not there : "protected by Jivings Apr 30 '14 at 14:43

Thank you for your interest in this question. Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site.

Would you like to answer one of these unanswered questions instead?"
Comment: But you have 101 rep :\ Are you logged in properly?  (Sorry if that's patronizing, I have to ask of course.). If so something is wrong.  I can ask around, but I won't really have time until tomorrow.  If you get it to work out, lemme know, otherwise I'll try and have more for you within 24 hours. It shouldn't be like this.
Comment: Yes I'm logged in properly, site works just fine. But the question seems to be an answer-protected, so I can't post a correct answer. And it's not a quest for correctness : the DHCP server is quite a frequent task people need, and it's an important element of server/router, and the answer selected there is not working. So I don't want other people get in trouble
Comment: Okay, [here's the reason](http://meta.stackexchange.com/questions/52764/what-is-a-protected-question):  "Users with 10 or more reputation can answer a protected question. However, the +100 account association bonus is ignored for this check, *so you must have earned 10 or more reputation on that specific site*".  I've edited that in (and some options), sorry for having wasted both our time here (really it is ambiguous in the banner, "earned on this site", but "we gave you 100 and it doesn't count").
Comment: Earning 10 rep isn't that hard, although this site in particular is very stingy E.g., I notice you've been a member here 6 months but only voted twice, presumably one of them the down on that answer :(  Not saying that's karma but...to be trite, sometimes the consequences of our own actions only becomes clear when we suffer them ourselves.
Comment: Thanks for clarifying the situation! It should be explicitly said in a help center, I think - to avoid such kind of situations. I'll do my best to earn 10 rep, and after posting an answer - I'll post here to let you know is it OK.
Comment: Added an answer with full details, worked OK =) Thanks again for your help!


How do you know if the shutter button is misfunctioning?

Question: I have a Panasonic GH3. It is very difficult to partially press the shutter button to focus as it often takes a picture at the slightest pressure. I thought this was my inexperience, but a couple of other people tried it recently and commented that it was overly sensitive. I don't suppose there is a setting in software to lesson the sensitivity is there? How can you tell if the shutter button needs adjusting?
Answer: To find out if this is normal, your best bet is to try another GH3, say in a store. Without trying it out, I cannot tell if it is normal but it could be. In my review of the Panasonic GH3, I described it this way:

This is a standard two-stage release with moderate travel to the soft halfway-point.

Indeed, the halfway-point is soft. If you push a little too hard you can easily miss it. This is why it is important to at least read about a camera's ergonomics if you cannot try it yourself.


Claiming EC261 compensation in another member state

Question: I had a delayed connecting flight Poland-Germany-Switzerland, for which I'd like to claim compensation based on ec261. I contacted the airline (eurowings) to no avail. I'd like to push the claim through the civil aviation organization.
But, different countries have different expiry time for the claim- it already expired in Poland.
Are there any guidelines regarding in which member state I can claim the compensation? Could I claim it, e.g. in UK that has a 6 year claim expiry time?
Answer: In the case of Rehder v Air Baltic, heard by the European Court of Justice, 9th July 2009 (Case C-204/08), the ECJ ruled that the jurisdiction in these cases is:

in respect of a contract for air transport services from one member state to another member state which is made with one sole airline as the operating carrier, the court having jurisdiction to deal with a claim for compensation founded on that air transport contract and on the Passenger Rights Regulation is the court having jurisdiction over the place of departure, or over the place of arrival of the aircraft.

http://www.mondaq.com/x/89712/Marine+Shipping/Jurisdiction+For+Claims+Under+The+Passenger+Rights+Regulation
So no, you cannot claim in the UK for something that happened in either Poland or Germany.
Comment: To complete this answer, sygi can therefore make his claim at the place of arrival in Switzerland, provided the local laws permit claims to be brought this late. Whether the Swiss civil aviation regulator would wish to get involved is another matter.
Comment: And do you think I can claim it in Germany? The delay was caused by the first leg late arrival (and subsequent flight missing and rerouting).
Comment: @sygi yes, the ECJ ruling is clear on that - jurisdiction exists at both ends of the flight.  And as Calchas suggests, it would be almost certain that that jurisdiction extends all the way to Switzerland, however as Switzerland is not a member of the EU, I have no idea whether the courts there would support any claim made under an EU regulation.


Can I use the spare donut again if needed after it has been filled with Fix a Flat?

Question: I recently had to use a spare donut since I got a flat tire.  I was stranded on the road and my spare donut did not have much air.  Someone helped me and changed the flat tire with the donut and filled it with 'fix a flat' can.  Now, I have replaced the donut with a new tire.  However, I am not sure if I can use the donut in the future (if ever needed) since it was inflated using fix a flat??  Someone mentioned, once you use fix-a flat, you cannot re-use the same tire.
Comment: "I have replaced the donut with a new tire" your question is a bit confusing. If you replaced the old donut tire that was inflated with faf, then you are good to go.
Comment: @Moab - The question is about the donut and reusing it as a spare with F-A-F in it, versus getting a new donut. The OP still wants a viable spare ... still usable or replace it?
Comment: Yes ..as Pᴀᴜʟsᴛᴇʀ2 mentioned...I want to ensure that my spare tire is still usable if I ever have to use it in future
Answer: You absolutely can use it again. The places that change tires try to discourage people from using fix-a-flat because it makes a mess when they go to remove a tire, but it doesn't take away from the integrity of the tire.
That being said, it's probably a good call to keep another can of fix-a-flat in the trunk. In my experience, fix-a-flat doesn't do a great job at fixing flat tires, though what it does do a good job of is inflating tires that have slow leaks. Since your spare was flat, it probably has a slow leak, and when you go to use it again, it might be flat. If that happens, you can just use the extra can of fix-a-flat to inflate it again.
Best of luck!


Is salt related to smell?

Question:
Can the salt content affect the fragrance of the dish?
If so, how does it happen?
Does salt have a fragrance of its own?
Answer: Salt itself doesn't really have a perceptible odour.
However, salt added to other ingredients will usually react with some of them, which will indeed cause a change in the dish's overall smell.
There are several different reactions involved:

Salt will draw fluids from most fruit, vegetables and meats. The fluids have an odour that was previously trapped within the food's structure and is now available to your nose.
Salt makes a fluid more acidic, which causes all sorts of changes. For instance, the difference in smell (and other properties) between a fresh cucumber and a pickled cucumber is mostly due to the brine, which is water with a high salt content.
Salt may facilitate other chemical reactions in the organic molecules of the dish. Obviously, different molecules have a different smell.

Each of these reactions may occur separately or together, depending on the specific ingredients used and a host of other factors, of course, but salt can definitely cause a change in the smell of a dish.
Comment: item 2: the difference in smell between a fresh cucumber and a pickled one?... I'm no chemist, but the odor contribution of the salt has got to be minor compared with the vinegar, dill, & whatever else was used to pickle the cucumber.
Comment: @Lorel C.: Of course, a lot of the change is in the other ingredients, but there is a change just from the brine itself. Try pickling cucumbers in brine with nothing else added and see what they smell like. They won't be good, but they;ll be different to fresh cucumbers.
Answer: First of a couple of assumptions:
1: Salt may react with other ingredients in ways that I can not oversee
2: Your question is purely about the way a dish smells off the plate, not indirectly when chewing.
The answer in principle is no. This topic has been discussed elsewhere on Stack Exchange, so you can read some of the theoretical background there.
Comment: Yes, my question is about smell not taste.

Is salt related to smell?


What is an easy way to update the addresses of hooked functions in an exe

Question: I have hooked into some functions in an exe. I was wondering if there were any simple ways to detect the memory addresses of these functions after the exe has a new build (not my exe). Is the best way to just scan the exe for the bytes of the function and compare to the previous result? Can this be achieved fast enough to add it to my injection code?
Comment: Just to be clear - you are trying to automatically find the addresses of functions in a new exe, based on the addresses in the old one, right?
Comment: Yeah, I need the new address of the function.  I tried scanning memory and comparing bytes, but that didn't work out so well. Do you have any suggestions?
Answer: It really depends on the functions you're hooking. If they're not likely to be changed, then scanning for the bytes would be the naive solution. It should be relatively fast and work perfectly fine.
If it's likely that the functions will have changed (patches, removal, different compiler/build env, etc) then you could try to find a bytestring 'signature' for those functions. Ideally that signature would be unique (only in that function), but also as small as possible (to reduce the likelihood that those bytes were patched in the new binary). This is going to be fairly hack-y.
Just a note: if it was a DLL, you could walk the PE export table fairly trivially to find the new offsets.
There's also Bindiff, which is now free: https://security.googleblog.com/2016/03/bindiff-now-available-for-free.html
Bindiff is an IDA plugin that would probably solve your problem as well.
I would say try scanning for the bytes, and see how many you're successful in locating. The easy solution is the best solution! :)


Are extended chords assumed to have each extended interval below it and a 7th?

Question: For instance, is a 13th chord assumed to have an 11th, 9th, 7th, 5th and 3rd along with it unless otherwise noted? And a 9th is assumed to have a 7th along with the triad, an 11th is assumed to have a 9th, 7th, etc.?
Comment: When you say "does it have" - do you mean 'conceptually', or 'as actually arranged/played'? Or both?
Comment: Both I suppose, but I mostly mean conceptually. On its own, does it usually imply the addition of the lower extended intervals.
Comment: @topomorto - The problematic part is that I'd answer both questions the exact same way. I was adding a comment to one of the answers here when I realized I had a niggling feeling that I'd answered the same question before, so I found it.
Comment: @Dekkadeci I think the "how do you voice..." question relates to how the chords are *arranged/played'* - which according to OP's previous comment isn't the essence of this question.
Comment: @Dekkadeci Do any of the answers on the linked question contain an answer as to whether the conceptual 'definition' of the extended chord *does* contain all the notes? According to my reading of this question, that's the answer that the OP wants.
Comment: voting to close, the existing answer covers this question completely.
Comment: @topomorto - While I read through all the answers of the linked question and none of them strictly and unambiguously answer whether the conceptual  'definition' of the extended chord does contain all the notes, I think I can copy and paste the accepted answer of the linked question verbatim to this question and there would be no accusations that the answer would be inappropriate or lacking (i.e. I can interpret the accepted answer as fitting this question, too, including the conceptual parts).
Answer: Technically, yes.
Extended chords are created by a process of stacking thirds, where you continue to add notes from the scale, proceeding in intervals of a third (of whatever flavour) to the highest note. A 13th chord, therefore, is a seven-note chord that theoretically contains all notes of the diatonic scale.
In practice, however, most often used voicings will not contain all the notes that make up the chord. This can be done due to voice limitations (for example: four part vocal harmonies; only six strings on a guitar, etc.) or in order to clean up the sound - as we might expect, playing all notes of the major scale, say, at the same time can get a bit of a mess.
A typical voicing will include just the main tones - the ones needed to bring the character of the chord accross. For four-part voicings this will usually be the root, the third, the seventh and the upper extension (9th, 11th or 13th). The fifth is usually first in line for omission, but may be included if it is diminished, or if it is necessary for the inversion.
Why these particular tones? The root is fairly obvious, especially when the chord is not inverted. The upper extension, likewise (otherwise we wouldn't know we had an extended chord or what kind). The seventh is a bit less obvious, but it allows us to differentiate between an extended chord and an altered triad - C6 v. C13, for example. The third determines the mode of the chord, so we can tell the difference between, say, C9 and Cm9.
Also worth mentioning, as noted in the comments, is that in certain cases we may wish to omit/include different tones because of clashes, e.g. we would omit the third in a dominant 11th chord (which forms a minor 2nd/minor 9th interval with the 11th).
Other than that, any important alterations - like the aforementioned diminished 5th - should also be included, possibly at the cost of dropping a note we consider less important to the sound of the chord (for example, the root when playing an inversion).
You will notice that such simplified voicings may sometimes appear to spell out different chords than what we're supposedly aiming for. That's ok. One person's C6 (C,E,G,A) is another person's Am7 (A,C,E,G). When it comes to harmonies, context is everything.
Comment: In 11th chords, the most commonly omitted notes are actually the 3rd and the 9th (at least for dominant 11th chords). For those chords, the 11th and 3rd correspond to notes a semitone apart, while in classical music, I don't recall an extended chord where notes strictly in between the 7th and what the chord is named after (e.g. the 9th in an 11th chord) were kept.
Comment: And note that while YOU may have a very firm idea of what notes are correctly in 'G11', there are other opinions!   A complete  'pile of 3rds'?   F/G?  G7sus4, G9sus4?   You'll find all of these (and probably others) labelled 'G11'.
Comment: I'm a bit confused on why we would omit the 3rd for a Dominant 11th chord.
Comment: Also, this question is a bit off-topic, but how come you can have a dominant 7th, 9th, 11th, and 13th but not a dominant 6th? Is it because it has to include a 7th to be a dominant? Also, why can't you have a diminished 6th chord? What if you had a chord like C, Eb, Gb, Abb? What would you call that? Cdim (+5)?
Answer: As a really simplified state, the last number note needs to be there. And, since it's above 7, that needs to be there as well. So a 9th will have 7 and 9; an 11th will have 7 and 11, and a 13th will have 7 and 13. Those last three could also be regarded as 7 and 2, 7 and 4 and 7 and 6 - all happily adding to the appropriate numbers!
Of couse, there's the primary triad to consider as well. 1, 3 and 5. So now, there could be a 5 note chord - easily playable on guitar - and obviously piano. As the P5 is heard to an extent in a harmonic of the root, that's the first to be let go. The root needs to be there - otherwise we don't really know what the chord will be called. However - if it's played on another instrument - bass/guitar, Sousaphone, trombone, for example, it needn't be in our cluster of notes.
The 3rd is left in - without it, the chord is neither major nor minor. Back to the 7th itself. There is usually a choice between major and minor here too, so it's important to use the appropriate one. Major 9 isn't the same chord as minor 9. Maj9 will have 1, 3, 5, maj7 and 9, whereas m9 will have 1, m3, 5, m7 and 9.
If we played every note in a 13th chord, it'd be all the diatonics. Often a mess, with clashes certainly between 3rd and 11th, so it's prudent - and necessary on guitar - to leave some notes out. To an extent, it's down to the player, the instrument, and what voicings get used. But, as earlier, simplicity works.
All that, and, the 5s and 9s get altered a lot - especially in jazz. Could be &flat5 or ♯5, so those don't get left out, because they're important to the sound of the chord. Same fate awaits 9ths, so something like C7♭5♭9 will need all the notes,if possible, and on guitar could end up being played on the bottom 5 strings as C E B♭ D♭ and G♭ on top.
So, bottom line. Yes, they could all be played. No, they're not all usually played. Use ears (as ever!) and judicious voicing, and put whatever you feel is best. But at least use my opening gambit as a start point.
Answer: Sort of.   We're all familiar with the 'pile of thirds' textbook examples.  And a 13th MAY include the 3rd, 5th, 7th, 9th - but almost certainly not the 11th, unless it's sharpened.
But see this quote from Piston.   Particularly note his comment that a 13th may often usefully be seen as a suspension (whether resolved or not).   And, if tempted to describe his second example as 'quartal harmony' consider whether it's merely a quartal voicing of triadic harmony.


Can I set up domain filtering on an Airport Extreme?

Question: I'm wondering if it is possible to set up domain filtering on an Airport Extreme based home network. Specifically, I'd like to block just rad.msn.com, and I need to do that at the network level.
Answer: Easiest way I know is to use a service like OpenDNS. You set up the Airport to send all DNS requests to OpenDNS and use their filtering (which can be quite sophisticated) to do the job of blocking or whitelisting web addresses. Of course you need to be able to protect the DNS settings on the Airport, but this is doable.
I have it set up for general filtering and monitoring on my home network which has more than 5 computers and more than a dozen wireless handhelds all served from an Airport Extreme.
Check it out at http://www.opendns.com/
Comment: I really don't like OpenDNS. Its really slow.
Comment: @CyberSkull It may or may not be slow for DNS queries, but they don't amount to a big proportion of the time it takes to do something on the internet. And the filtering benefits are large.
Comment: It seems OpenDNS is a paid service now. Is there anything free that would allow custom domain filtering/mapping?
Answer: Airport hardware doesn't have this sort of feature but you could easily accomplish this by running your own DNS on a computer or outsourcing the issue to a provider.
I believe you could also rely on an inexpensive router that did have this feature (or one where open source software was readily available) to run your DNS and let the AirPort handle the rest of the tasks on the network.


Good free m2ts to mp4 converter?

Question: I'd like to convert some AVCHD footage (.m2ts) to mp4 files. Can anybody here recommend a good converter (preferably free) that'll do a good job?
Answer: FFmpeg should be able to do this - assuming you don't mind getting down with the command line (there may be some GUI options out there too possibly).
My Olympus E-P3 produces .MTS files - I assume they're similar (AVC/AC3 in a Blu-Ray Video wrapper).
I ran the following command:
    ffmpeg -i 00001.MTS -vcodec copy -acodec copy -f mp4 00001.mp4
That just tells FFmpeg to copy the video and audio streams but put them in a new mp4 format (the -f option).
The resultant mp4 still has the same AVC/AC3 combination but now in a MP4 wrapper.
I played both source and output in VLC and they looked the same - obviously you should satisfy yourself that quality has been maintained.
I'll wager that most GUI tools to do this task use FFmpeg under the hood.
Answer: For Mac, there is a very simple and efficient solution that results in no loss of quality whatsoever, however it does require you to install some software.

Install the clipgrap app. This contains the necessary codecs required for step 2. You don't have to use the app again, and I just left it in the 'Utilities' folder in 'Applications.'
Download the 'Rewrap2M4V' file from this page. Put it on your desktop.
Now drag and drop your M2TS file onto the Automator icon of the file you just downloaded. An MP4 file will be created in the directory of the M2TS file.

Basically, the automator script changes the wrapper on the file from the awkward Panasonic one to a more friendly MP4. You can now edit or do whatever you wish with it.
The advantage of this solution is that it does not hinder quality through conversion as many converters do. It does not affect the actual file content itself. It is also very quick.
Comment: Alistair - thanks for that. Unfortunately I'm on Windows - any comparable solution?
Answer: I believe Media Converter can do this using one of the Re-Wrap AVCHD for Quicktime presets. Not sure what format you want your audio in, but one of them is PCM uncompressed. I've just modified the preset to AAC for my own purposes though.

Good free m2ts to mp4 converter?


Why Cookies must be Allowed for "Not Script" Extension to work in Chrome?

Question: I've been using "Not Scripts" v0.9.6 extension in Chromium browswer (currently v30.0.1599.101) from the last one month and found the extension extremely useful. However, after reading some tracking issues related to cookies, I decided to clean off all the cookies since the beginning and switched it to option "Block all cookies including third party as well". With no exception, I found that when this option is selected for cookies, the "Not Script" virtually get bypassed on every website rendering the extension useless for its purpose. I tried to post this question on their mailing list but someone already asked the same and received no answer.
May I know why exactly this problem is arising as I don't what cookies in my browser unless for Gmail and Facebook [only for sessions] ? Similar situation in Firefox with "NOSCRIPT" addon doesn't create any mess.
Answer: Not technically an answer to your question. But the Not Script extension for Chrome has not seen any development since 2010. I would recommend trying the Script Safe extension as a replacement. It uses a new script blocking API which was released after Not Script ceased development. A quick test on my computer seems to indicate it will work perfectly fine with cookies completely disabled.


Trackpad does not work in Ubuntu 11.10

Question: I just installed Ubuntu 11.10 on my Inspiron 1525. Now the trackpad no longer works and I have to use a USB mouse. Would changing the Desktop environment from Unity back to GNOME help or is there anything else I can do?
Answer: Problem solved. My first guess was correct and it was Unity. Installed GNOME3 and everything works fine. Looks great too.

Trackpad does not work in Ubuntu 11.10


Manually align images for time lapse

Question: I've been taking a picture of myself everyday for a few months now. I haven't used a tripod, so the images are not aligned at all. I'm looking for some type of software that will allow me to manually resize, rotate, and crop these images to I line up in all of them. I'm hoping for something where I can have one reference image that is a bit transparent and then I can edit every other image to match that one. Does any software like this exist?
Answer: With Gimp there is a script for this: ofn-layer-aligner. You create two pairs of points, one on the reference layer and one on the target layer, and it rotates/scales/moves the target layer so that the two points marked on it are above the two points on the reference. In your case I would:

Open the first picture, create the first two points (in the center of the pupils)
Then for each of the other pictures

File>Open as layers to add it as a new layer in the current image
Add (or move) the two target points over the pupils (you don't even need to see the reference image as long as you don't move the reference points)
Call the script

Crop the image when you are done (this crops all layers to the same size)
If needed export all layers as individual images (manually but there are also scripts for this), but you can also play it as an animation (Filters>Animation>Playback)

Manually align images for time lapse


Erroneous sensor reading while connecting extra load

Question: I'm making a speedometer using arduino. I've made use of the interrupt pins to achieve the same. My problem is with the power source. I'm using a 12 V battery supply to power the arduino and I'm also using the same battery to use a horn. But, whenever I push the button to sound the horn, the IR sensor connected to the arduino is getting activated and I'm getting an erroneous reading. The only common thing between the arduino and the horn is the battery supply.
Answer: If the horn has a speaker coil or other magnetic actuator in it, then it will present an inductive load that may cause a voltage spike when you turn it off.  Or, if it's a buzzer, it may generate voltage spikes all during its operation.  Voltage spikes or other electrical noise are the most likely cause of the problem.
It also is possible that the horn draws enough current to drop your battery voltage so low that the Arduino or the sensors don't function reliably.
To find out which is the problem, take voltage readings with and without the horn in operation.  If you have an oscilloscope, look for spikes on system power.
Try isolating and/or buffering the Arduino's power.  If power glitches are the problem, that should fix the problem.  If the problem is electromagnetically radiated electrical noise, further isolation (eg shielding) may be needed.
To isolate the Arduino's power, either operate it from another battery (which is something you can do anyway, while diagnosing the problem) or add one diode into the Arduino's power lead and another into the horn's.  Connect an electrolytic capacitor, eg 100 to 1000 μF, from the Arduino's +V input to ground.  If necessary add ferrite beads around the power leads.
A capacitor across 12 V from the battery will buffer the power, but for more isolation and buffering you can add a buck converter which can manufacture eg +7V from a +12V input while remaining relatively impervious to spikes on the +12V.  Put the large electrolytic across the +7V if you use a buck converter.
Comment: Thank you for your answer, but the thing is the arduino itself is not resetting or switching off during the horn operation, it's perfectly driving the GUI display and other stuff it's used for. Only the values are changing. And yes, the voltage is dropping very much across the battery( low CCA, I suppose) but not directly affecting the arduino's operation.


Finding cubic polynomial equation for 3 joints

Question: My professor gave us an assignment in which we have to find the cubic equation for a 3-DOF manipulator. The end effector is resting at A(1.5,1.5,1) and moves and stops at B(1,1,2) in 10 seconds. How would I go about this? Would I use the Jacobian matrix or would I use path planning and the coefficient matrix to solve my problem. I'm assuming coefficient matrix but I am not given the original position in angle form. I was only taught how to use path planing when the original angles are given.
Comment: I would use inverse kinematics to determine the motions of each joint (start and end positions).  Then use path planning to set the desired motion profiles for each axis over those ten seconds.
Comment: Does it have to be in joint space?
Comment: Good comment @50k4.  You could plan the trajectory in Cartesian space, and then use inverse kinematics repeatedly throughout the 10 sec to stay on that path.   The nice thing about that approach is you can keep the end effector on a linear path during the trajectory.  However, it requires repeated inverse kinematics in the motion loop, which the earlier approach does not need.
Comment: Well, it depends on the exercise, I mean if it is a theoretical exercise about trajectory planning, solving the inverse kinematics seems to be an unneeded overhead...Cartesian curves might be enough for the exercise...
Comment: Welcome to *robotics* Jimenemex. On stack exchange, questions asking for homework help must include a summary of the work you've done so far to solve the problem, and a description of the difficulty you are having solving it. Please edit your question to add this information.
Answer: I guess you want to find a cubic polynomial for the end effector. You have 3 coordinates for your points A and B, from your question is not clear if they are $x,y,z$ or $x,y,\theta$. Anyway, I'll show here the procedure for $x$, and you can repeat it for the other two coordinates.
Given the cubic parametric form $x = a_0+a_1 t + a_2 t^2 + a_3 t^3$ ($*$), you want to find the parameters $a_i$.
At $t=0$ you know that $x = 1.5$, so from ($*$) $a_0 = 1.5$.
At $t=10$ you know that $x = 1$, so from ($*$) $a_0+10a_1 + 100a_2 + 1000a_3 = 1$.
Let's differentiate the polynomial: $\dot{x} = a_1 + 2a_2 t + 3a_3 t^2$ ($**$).
At $t=0$ you know that $\dot{x} = 0$ (rest condition), so from ($**$) $a_1 = 0$.
At $t=10$ you know that $\dot{x} = 0$ (stop condition), so from ($**$) $a_1 + 20a_2 + 300a_3 = 0$.
So you have:
$a_0 = 1.5$
$a_1 = 0$
$a_0+10a_1 + 100a_2 + 1000a_3 = 1 \Rightarrow 1.5 + 100a_2 + 1000a_3 = 1$
$a_1 + 20a_2 + 300a_3 = 0 \Rightarrow 20a_2 + 300a_3 = 0$
From the last equation you get $a_2 = -15a_3$, substituting in the second last you get $a_3 = 0.001$, and substituting $a_3$ back you get $a_2 = -0.015$.
So you have all the $a_i$ coefficients to replace in $(*)$ and you can get the solution $x(t) = 1.5 - 0.015t^2 + 0.001t^3$. You can do the same for the other 2 coordinates changing the initial and final conditions.
Comment: Can you explain how you got to the final equation for x from using the previous two?
Comment: I edited the question adding more details. Basically, you have a system of four equations and four unknowns.


Can a CA decrypt HTTPS traffic?

Question: My state has made a statement that in case my country will be disconnected from the world's CAs, it is necessary to install its own state certificates. In many forums, information has flashed that in this case, having its own certificate, the state will be able to decrypt all HTTPS traffic. Is it true or not?
Comment: As a bit of a bonus: Exactly this was attempted in 2015 by Kazakh authorities for exactly this reason: https://en.wikipedia.org/wiki/Kazakhstan_man-in-the-middle_attack
Comment: "disconnected from the world's CAs" What does this mean? That internet communication with the world's CAs will be blocked? That it will no longer be lawful for local entities to be able to obtain certificates from the world's CAs?
Comment: @ReinstateMonica I'm not exactly sure what this means, you can read the news in the attached link
Comment: Not an answer but start looking into https://tails.boum.org/, if it can help.
Comment: You can't meaningfully "disconnect from the world's CAs".  Non-Russian CAs might refuse to issue certificates for Russian businesses, but anyone who can get a copy of the root certificate for a CA can validate any certificates issued by that CA.
Comment: Note that the two links are to `.ru` domains. In light of all the sanctions against Russia for their actions in the Ukraine, my guess is that the government is preparing for any and everything. Whether they would or could cut off access to CAs outside Russia is a debate for a whole different forum.
Comment: @Mark: Moreover, I would expect Let's Encrypy to continue attempting to provide ACME service to the best of their capability (which might be limited by blocking, but hard to block fully).
Answer: Yes, this could enable your state to spy on HTTPS traffic. That's not just an imaginary threat, it happened in the past in a private company and it was attempted by a state.
CAs are a centerpiece of a trust system. Once your browser trusts a CA, in this case a state controlled CA, it trusts all the certificates signed by it. Now, your state-controlled ISP could use fake but trusted certificates to intercept traffic to any website, like the BBC or Bellingcat for example, and your browser would not stop it because it would look legitimate. HTTPS is meant to prevent such attacks. Trusting a rogue CA completely breaks HTTPS. This more recent answer by jcaron details this process.
Note that technically, it's not the rogue CA that decrypts the traffic. It provides the means for interception by other networks actors to remain undetected by the browsers.
Comment: It's worth pointing out that a rogue CA that can hand out illegitimate certificates to bad actors (which appears to be what the OP is alleging to) only enables MITM attacks using those illegitimate certificates. In absence of a MITM attack, a HTTPS connection set up using a genuine certificate would still be safe; illegitimate certificates (or their keys) can't be used to decrypt traffic encrypted with another certificate. So the answer to the exact question asked ("decrypt _all_ HTTPS traffic") would be _no_, strictly speaking. It might be worth addressing that in your answer.
Comment: @marcelm Since HTTPS is negotiated in the clear, and this communication happens over the state-owned ISP, the state would be able to MITM *all* HTTPS traffic if they so wish.
Comment: You shouldn't say "Trusting a rogue CA completely breaks HTTPS" because that implies that you lose all your security and might as well use HTTP. HTTPS with a malicious trusted CA still protects you from passive eavesdropping and from active attacks by anyone not colluding with the CA. Moreover, it just takes a few people checking certificates (e.g. via pinning) to publicly expose the rogue CA. So either the attacks will be narrowly targeted (probably at someone other than you) or they won't last long.
Comment: @benrg Thank you. This is one of my pet peeves. People like to say things like "the main purpose of HTTPS is to prove who you're talking to is who they claim to be." That is important, but I would argue that the main purpose of HTTPS is to encrypt traffic.
Comment: @benrg: True, but that doesn't really help a lot here. We already know Russia went rogue. There's nothing left to expose.
Comment: Thanks @Hobbamok, I added your link into my answer.
Comment: A good friend of Russia tried EXACTLY this a bit back: https://en.wikipedia.org/wiki/Kazakhstan_man-in-the-middle_attack
Answer: To illustrate in more detail what A. Hersean explains:

In normal usage, when you visit https://security.stackexchange.com, the security.stackexchange.com server presents a certificate which is signed by a CA your browser trusts (ISRG Root X1 in this case).

security.stackexchange.com is (normally) the only one having the private key
security.stackexchange.com is the only site which can decrypt the traffic you exchange with it.
You know you are talking with the real security.stackexchange.com.

If someone manages to intercept the (encrypted) traffic between you and security.stackexchange.com (by placing a device somewhere on the route between you and the server, or by manipulating DNS so your computer sends the traffic to a different server), as long as you don't trust rogue CAs, either:

they just access the encrypted traffic and they can't do anything with it
or they pretend they are security.stackexchange.com, so they need a certificate for security.stackexchange.com, and they normally can't get one signed by a CA your browser trusts. If they generate a certificate signed by somebody else (or a certificate signed by a CA you trust, but for a different site), you get a big error message in your browser.

If you trust a "rogue" CA like the one they tell you to, then suddenly that CA can start generating certificates for any site without checking ownership, and they will be trusted by your browser (no error).

The people who intercept your traffic to security.stackexchange.com (as above) get a certificate for security.stackexchange.com from that CA even though they are not security.stackexchange.com
This allows them to act as a proxy (they receive the traffic to security.stackexchange.com, decrypt it, maybe filter or analyse it, and then connect to security.stackexchange.com as if they were a regular client).
Or they can present you something completely different. Your browser thinks it's talking to security.stackexchange.com, so you think you are visiting that site, but they serve you a page talking about denazification instead.

So it's not the CA which decrypts the traffic, but they can enable others to do so by giving them certificates you trust even though they shouldn't (because they are not really security.stackexchange.com).
This is the way most countries trying to control everything which is exchanged act. They just ask you (or force you) to trust their CA, which allows them to eavesdrop, filter, censor, block or modify anything they want.
This is also the way many corporate proxies/firewalls work.
If you have a choice, do not trust that CA. If it were trustworthy they would follow the standard procedure to be approved by the OS/browser vendors, following the rules of the CA/Browser forum. If they are not approved, that most likely means they are not trustworthy.
Comment: @bobuhito, no, your browser doesn't know or care about of the existence of any other certificates. The only certificates involved in validating a cert are: the end entity cert provided over the connection; and the cert(s) that signed it. The signing cert must be one in your browser's Trusted Root CA store.
Comment: Relevant mitigation: https://en.wikipedia.org/wiki/Certificate_Transparency
Comment: If you trust the wrong CA you are pretty much hosed until you stop trusting that bad CA.
That's one of the biggest flaws in the whole SSL setup, who to trust?. Unfortunately, this is one of the *really* hard problems with afaik no good technical solutions.

Arguably it's not a technical problem, so we shouldn't expect to get a technical solution
Comment: And an actual attack is much easier if a state controls your CA, and the same state controls your ISP. (Because your CA must create a fake security.stackexchange.com certificate, and your ISP is in the best position to redirect you to a fake security.stackexchange.com website).
Comment: In your third case (the dangerous case where I "trust a rogue CA"), shouldn't the browser tell/warn me that there are two different trusted security.stackexchange.com certificates available (the rogue one and the correct one)?  I am using Google Chrome, so let us suppose that Google makes just the mistake of including a government-issued rogue CA in their trusted list in the next Chrome release.  Of course, if I mistype "security.tackexchange.com", I won't get this warning and am therefore in greater danger.
Comment: @bobuhito The certificate used for a connection is (almost always) provided by the server when you connect. IOW, you get what you get, and have no way to know that other certificates exist. You could in theory compare to a previous certificate, but warning about a mismatch there s generally not done because certificates get renewed all the time, and while it's uncommon it's not unusual for a site to change which CA is issuing it's certificates.
Comment: This is perhaps a different question, but what can OP do in this case? Are they doomed?
Comment: @throx Too bad that CT is typically ignored for manually installed trust anchors. (It simply has to be as otherwise various "internal company CAs" would be entirely useless as there's no way to get certificates from them into the CT logs.)
Comment: @TooTea: Doesn't have to be. If it resolves to a public IP address, lookup the host on all in-box certificates. If you get a match, you know somebody's hijacking. If you can't get through to too many transparency servers you know shenanigans are afoot. Also, publish the cert to some sensor server; if the cert's being abused it can be hardbanned.
Comment: One point about: "If it were trustworthy" line: Some western CAs are revoking already existing Russian certificates, which leads to fears, that the Russian CAs would automatically be excluded from the "standard procedure" of OS/Browser vendors, which would leave the end-users of Russian websites with no trusted party which would vouch for the proper functioning of Russian CAs. Quite an unfortunate situation.
Answer: There are two ways for decrypting HTTPS traffic:

By getting access to the private key
By generating a new key pair and issuing a new certificate for a specific domain you want to get access to the HTTPS traffic. However that requires an active man-in-the-middle attack and users may be able to detect such an attack assuming that the CA does not have access to the private keys of all the generated certificates. In such a case they have to generate a new key pair which can be detected by the client if you know the real public key of a certain domain.

For the first case if the CA works as designed issuing a new certificate then no, they can not decrypt your HTTPS traffic.
The designed work flow is that the you generate a private key and a certificate signing request, send that to the CA and get back the CA signed certificate. As the private key is only known to you the HTTPS traffic is safe.
However a number of CA provide a "service" where you just say "I want a certificate" and they generate the private key for you, generate and sign the certificate and send everything to you. In such a case the CA might get access to your HTTPS traffic (depends on the used TLS version and cipher suite if for doing so a passive attack is sufficient or an active attack is required).
For example if the HTTPS connection uses a cipher that has the Perfect Forward Secrecy property even someone in possession of your private key can not decrypt the traffic if only a passive attack (network sniffing) is performed.
Comment: The question is about adding a potentially-untrusted CA as a trust anchor. Once that happens, said CA can issue a `*.com` certificate or something similar to facilitate MITM attacks against third party servers. It has nothing to do with private key escrow.
Answer: There are 3 threat models that are relevant here. Keep in mind that when I say "the state" I am including groups the state can force to obey them.

The state is just a CA and can't see or modify your internet traffic: You are totally safe (in this scenario even plain HTTP is safe)
The state can see but not modify your internet traffic: You are safe as long as the website keeps their private key private OR you are using a protocol with at least weak forward secrecy (ex: TLS 1.3)
The state can intercept and modify your internet traffic: If the website keeps its private key private AND you are using a browser that requires certificate transparency AND your browser doesn't make exceptions for the state owned CA (see Chrome's policy about not enforcing certificate transparency for manually added CAs) then depending on the attack strategy the state chooses, EITHER your browser will warn you of the attempt to intercept traffic (net::ERR_CERTIFICATE_TRANSPARENCY_REQUIRED) OR the fraudulent certificate will be publicly logged and the website owner will be alerted after the fact (if they have a CT-log monitoring tool/service configured).
Comment: You forgot to include the case where a browser not using certificate transparency is used.
Answer: This is routinely done by commercial antimalware filters, mainly in the big corporate networks:

The anti-malware software instantiates its own CA.

The root CA certificate of the software in question is distributed over the internal network.

The network traffic is routed through the anti-malware software.

the software plays "man-in-the-middle" attack for every connection.
It represents a created on-the-fly certificates signed by its own CA to the clients. Clients track these certificates to the software's own CA (installed in their trust stores) and trust them.
The traffic is decrypted on the anti-malware scanner and then reencrypted when sent to the server or to the client.
Other things, like content-scanning, activity logging or changing the content on the fly can also be performed.

In the better case, you get less ads in the pages you browse (and, hopefully, less viruses).
In some cases, your friendly sysadmin looks at your social network activities.
In worse cases, they report your personal mail password to your boss.
The government, in general, can do all of the above. You only need to have their root CA installed.
What is distinct from your corporate network is that you will not have the option to use your personal computer/smartphone for your private communications and there is no legal limits on how the government can abuse these abilities.
Well, there probably will be legal limits, they will just not be enforceable.

p.s. the real solution is to either emigrate or fix your government.
... or wait until the world fixes your government for you, just like Germans did until 1945.
Answer: The short answer to your question is No, or Yes, or Maybe. But I think you need to understand what's happening.
Let's say A wants to communicate with B securely, using https. Maybe A is my iPhone, and B is Amazon.
Each side has a private/public keypair, and the start negotiating. They exchange data, derived from their keys and from what the other side sends, except they don't exchange the private keys.
They use a very clever algorithm that lets you decrypt B's messages if you have all the data exchanged during the negotiation plus A's private key, and to decrypt A's messages if you have all the data exchanged plus B's private key. But if you have all the data exchanged without one of the private keys, you have absolutely nothing. To decrypt anything, you must be part of the key exchange.
So to decrypt, a hacker (or your ISP) must redirect your key negotiation from Amazon to someone else. But there's a problem: My iPhone will insist that the other side (which is supposed to be Amazon) provides a genuine Amazon certificate. A normal hacker or your ISP don't have that certificate.
Your CA also has no chance to get Amazon's certificate. But anyone can create a certificate that claims to be Amazon's certificate, except nobody will be tricked into believing it's genuine. Here's where the CA comes in: If the CA signs the certificate, and my iPhone believes the CA is genuine, then the certificate will be accepted.
So if you have a CA that signs fake Amazon certificates, and an ISP willing to redirect my Amazon traffic, AND my iPhone believes the CA is genuine, then they can read all my Amazon-related traffic.
Now this wouldn't last long because Apple (and Google, and Microsoft, and everyone else) would figure that out and the next software update would remove that CA. None of the certificates they ever signed would work. So a rogue CA together wit a rogue ISP could do this for a very short time, then the CA will be effectively shut down.
Here is where the power of the state comes in: If Russian police can stop you in the street, and demand you let them install their CAs root certificate or your phone gets destroyed (or you go to jail), yes, then they can read all your internet traffic. Apple will protect you from some hacker doing this, but they can't protect you if armed police force you.
Answer: CA's do not receive the encrypted traffic sent between third parties, and would not be able to decrypt it, even if they did.
But, if the State can force you to accept their State CA certificates for web sites you may be accessing and they have the private keys for those certificates (and they would since that's why they would do it), the State would be able to decrypt your traffic through a Proxy somewhere in the traffic flow between you and your web site.
This is known as a 'man in the middle' attack on the privacy of your communication.
Comment: This just seems to repeat the top voted answer. Were you hoping to add something new?

Can a CA decrypt HTTPS traffic?


Criteria for excluding an Asset Class from a Strategic Asset Allocation

Question: While historically the return, volatility and correlation characteristics justified the inclusion of Sovereign Bonds (US Treasuries, European Central Bank Debt, etc) in Strategic Asset Allocation decisions of real money investors (such as Pension Funds), are they justified in today's investing environment?
With Sovereign Bonds offering zero or even negative expected returns, and offering very little diversification benefits (recently Sovereign Bonds offered almost no protection to Equity drawdowns) do they belong in a Strategic Asset Allocation?  Yes, I never anticipated negative rates and I suppose they can get even lower and offer some potential for capital appreciation, I have a hard time believing there is much capital appreciation left.  At the same time, they offer a negative yield and pose a high potential for capital depreciation should rates rise.  Do these investment characteristics justify their inclusion in any Strategic Asset Allocation?  What criteria should be used to include or exclude asset classes in such Strategic Asset Allocations?
Answer: This discussion might be of use: Asset Allocation with near zero rates.
I have heard (at conferences) large, institutional investors say they are reconsidering their allocation to govys and/or IG because of ZIRP and NIRP. I don't know what criteria they use to make their strategic asset allocation decisions or whether they've implemented any changes.


Salesforce Flows by default selects a picklist value

Question: I have a flow in which there are two dropdown fields. By default Salesforce makes these fields mandatory (No complaints) but it is defaulting the first choice value. I want that not to happen. I want the flow to provide a default option like "--Select One--". In reality, I can create a separate option called "--Select One--" but then to enforce the validation I will need to add couple more screens and assignments to validate the inputs. It will not be scalable if in the future I add more and more dropdown fields.
Answer: I know from working with VF and other sources that if there is no "none" option that usually means that the field is marked as required in the field definition. This is evidenced by the fact that they are marked as mandatory in your flow.
You can remove the required flag on the field and update all the page layouts to show that field as required. This will make sure end users have to enter a value but allows you more flexibility in your automations.
Record Types
I believe it's also possible to add a "none" option to the picklist in the record type definition if you are using record types for your object. From my experience this is only enforced if the record already has a record type (if you're editing an existing record or if you create a new record and explicitly set the record type before showing the fields to your user). This is something I've done in Visualforce, I'm not sure how well it'd work in a flow but it could be worth a try.
Comment: Thank you for the response. In the flow I am not using the picklist field on the Object. I am creating a picklist inside the flow itself.
Comment: In that case I think you only have the 2 options, create the entry and deal with validating it or do not create the entry. I'd personally just not create the entry and set the default to what ever you think is the most likely response.
Comment: Thank you. Option#2 is not an option and Option#1 I was trying to avoid. Looks like it is what I need to do for now.


How to monitor calls to an external library function?

Question: I have an application which is executing oci statements using OCIStmtExecute(). I need to know which sql statement is being passed to OCIStmtPrepare on what action. Tried using API Monitor but there weren't OCI.dll functions. Also placing a breakpoint doesn't help since it's executing a notify statement almost every half a second.
Comment: If you use WinDbg, you can set a breakpoint, have it dump out the parameter, then continue execution.
Answer:
Tried using API Monitor but there weren't OCI.dll functions.

OCI.dll most certainly does export functions, including OCIStmtExecute() and OCIStmtPrepare():

If you're not seeing them in API Monitor, it's because you've not told API Monitor to log them correctly, or because they're not really being called by the target process.
Comment: How do i tell API Monitor to log them ? I'm certain that the application is using those functions.
Comment: You need to use its _External DLL Filter_ functionality.
Comment: I'm checking boxes next to functions but it doesnt help. Do i need to set another filter for them from somewhere ?
Comment: You may want to post your question on API Monitor's web forum: http://www.rohitab.com/discuss/forum/1-api-monitor/
Comment: API Monitor worked perfectly. Apparently i wasn't selecting application module while applying filter. Thanks.


Why is there a separate Stack Exchange website for Wordpress?

Question: Why does https://wordpress.stackexchange.com/ have its own site? I'm not saying it's pointless; the stuff over there's invaluable. I'm just curious as to why it couldn't just go on the WordPress tag on StackOverflow, which has significantly more traffic.
Comment: Thank god there is a different site for it, if you know what I mean
Comment: It can usually go on either site.  Presumably wordpress.se also allows some not-so-programming related questions about wordpress that would be borderline off-topic on SO.  See [their  on-topic page](https://wordpress.stackexchange.com/help/on-topic)
Comment: The same question could be raised for most of the other sites in the network (or at least, the technically oriented ones, anyway). There are similar sites for Joomla and Drupal (ie the biggest direct competitors for Wordpress) and a number of others.
Comment: Can you share statistics on "has significantly more traffic"?
Comment: @Nemo - Purely anecdotal. If I cross post a question on SO and WP.SE, the SO version will always get more views.
Comment: Ah ok. Let's see, I took your top Wordpress.SE question and a  [wordpress] SO question with same upvotes and the views/month are comparable. http://wordpress.stackexchange.com/questions/168981/how-do-i-go-straight-to-edit-more-details-when-clicking-on-an-item-in-the-medi http://stackoverflow.com/questions/32496120/wp-enqueue-scripts-not-firing-in-wordpress Definitely worth investigating (assuming we're able to  compare questions which are equally in scope for the respective site).
Comment: The other site is not a trap! We did not create wordpress.se to tag, to alienate or isolate your kind. All we just want to help! There is no danger.. You can trust me!
Answer: My reading of it goes like this:
StackOverflow is very specifically for programming questions.
A lot of Wordpress issues are not programming problems, but down to configuration, or choosing the right plugins, or how to work with themes, etc etc.
Those sorts of questions are explicitly off-topic for Stack Overflow, because it's a site for programming problems. But they are on-topic for Wordpress.stackexchange, because it's a separate site with its own rules about what is on-topic or not.
So the bottom line is that if you have a question that about problem with some code you've written for Wordpress, then it is probably on-topic for either site. But if your Wordpress question doesn't involve code that you've written, then it probably belongs on wordpress.stackexchange.
Comment: That makes sense - I think because I only tend to go to the WordPress site for programming questions, I was seeing more of a crossover than there necessarily is.
Answer: Stack Overflow is more popular as a whole because it's more of a generalized site. It's a "catch-all" for development questions so people from all languages visit it daily. WordPress Stack Exchange is a very centralized exchange dealing specifically in WordPress development practices. The [wordpress] tag on Stack Overflow can exist in conjunction with WordPress Stack Exchange because what may be on-topic on Stack Overflow would be considered off-topic on WordPress Stack Exchange.
WordPress Stack Exchanges purpose is to help people understand how WordPress works, how it's core functions work, and how they can use those functions in their theme development or plugin development. Here you'll get the best references and quality answers from people who work with WordPress daily.
WordPress Stack Exchange is not a place for general PHP questions or questions about 3rd party plugins whose functionality lies outside the of WordPress core. Questions where you need to understand woocommerce_content(), which is not part of WordPress but instead part of the 3rd Party WooCommerce plugin, would be off-topic.
Stack Overflow is a place that allows all development questions which include asking to understand 3rd party code such as WooCommerce which is why the two sites can live in conjunction. I would also like to point out that having a site specifically to a CMS such as WordPress lessens the noise of other questions you may not care about on Stack Overflow, like an overall filter of questions specific to WordPress. Finally, you're more likely to get an answer to your WordPress questions on the site specific WordPress Stack Exchange than Stack Overflow as it seems the answer-rate for WordPress tags are below ~50%.


Keeping a dog inside the house

Question: Assalamou ailekom
I would like to know if my prayers are accepted or not if I have a dog in the my house. My brother adopted it without permission from us but we had to keep it since we got emotionally attached to it. I know that angels don't enter the houses of people who keep their dogs in their houses and that's dogs are just permissible if they are guard dogs. We see it as a pet but it can serve as a guard dog too maybe because when guests or strangers are comming to our house the dog goes to window so we know that someone is coming. So I'm a little confused if it's a sin or not in our case to keep the dog. Thank you in advance.
Answer: From what I know, which isn't a lot, having a dog inside your house is not permissible, if you want to keep it as a guard dog you can keep it outside your house, however in cases of cold the dog can not come inside the house. You can feed it by placing it food in a bowl or something, but make sure to avoid it licking you. In general, your interaction with this dog should be minimized. I think a cat would be a beautiful option for a pet, also I am not sure how religious your family is but there should be no such thing as a child disobeying their parents if not asked something haram or beyond their capability. It is your responsibility to advise your brother too, May Allah grant you peace and guidance. Salam
Answer: It is permitted by the Hanafis to buy and sell dogs for a lawful purpose, e.g., hunting, guarding, guiding the blind and so on. Imam Malik permitted it regardless however the other schools of thought prohibit such buying and selling.
All, however, allow a price to be given for relinquishing control of a dog - which differs from a sale in that the one relinquishing control does not carry the usual responsibilities associated with a sale such as quality, fitness for purpose, delivery etc.
The Prophet (saw) said:
"Whoever keeps a dog, two Qirats (a huge portion) of the reward of his good deeds is deducted daily unless the dog is used for guarding a cattle or for hunting." (Bukhari and Muslim])
So if the dog is used for guarding and other permitted matters by the Shariah, then there is no problem.
This article gave a detailed explanation with dissected evidences
Answer: I think it's about keeping dogs as servants, to prevent people from keeping them for eating.
"Keeping" - is the same thing no matter inside a house or outside.
Comment: what's your source?
Comment: Same as already quoted here. I just disagree with interpretation.
I believe that Islam is also about thinking with your own head and conscience instead of blindly relying on scholars' opinions.

Keeping a dog inside the house


What was the point of the Babylonian captivity?

Question: What was the point of the Babylonian captivity?
I could understand if a few royalty or nobility were taken hostage, but why tens of thousands? I see no suggestion that they were taken into slavery. What was the advantage to the Babylonians?
Comment: My suggestion is to treat all the large numbers reported by any sources in antiquity with a huge grain of salt (numbers of participants in battles, casualties, captives, etc.).
Comment: Point was pacification, method was exile of those most likely to cause rebellion. As Moishe pointed out, numbers should be taken with the grain of salt.
Comment: I think this might be a case to discuss on [meta]. Based on formalities, I'd agree that the question would benefit from improvements and should receive an [edit], ideally before re-opening. — But the now stated close reason seems also obviously 'just wrong'. Since this seems to be a rather common problem here, with apparently some users taking the default position of "anything touching 'the bible'" would be per se ahistorical/religious matters (?) we would benefit from prospecting the dividing lines and definitions of site scope on these topics?
Comment: The answer by LаngLаngС , with facts and citations,  is what I was looking for. I don't see how I could have been more specific without already knowing the answer.
Comment: This belongs under religion, not history.
Comment: @jamesqf Well, this is one where everyone, in a sense, points to the Bible; believers say it happened taking the Bible as the authority on the matter, while sceptics say it happened taking the Bible as the product of their stay and cultural borrowing.
Comment: Why do you suppose they were not slaves (meaning involuntary workers, bought and sold, kept against their will)? The big point of invading other countries in those days was to bring home valuables, and prisoners had a huge value.
Comment: @Luke Sawczak: But how, without more than the trifles of actual evidence that seem to exist, do you separate whatever grains of history there may be from the religious chaff?
Comment: @RedSonja I think that's a good basis for an answer that challenges the frame of the question (and FWIW, I think you are correct)
Comment: @RedSonja That is what I was asking. They always seem to say "captivity"  in Babylon vs. "enslavement" in Egypt. But now I am not sure this is even history, I have been conned by Wikipedia's bible-stories=history policy.
Answer: Just like the better researchable Assyrians the Neo-Babylonians employed this as a proven tool to assert their control of the conquered lands and the remaining people there.
Once the head of the snake is removed, it is no longer needed to crush that head?
The Assyrian policy of deportation is analyzed as

punishment for rebellious behaviour;
liquidation of competing powers and weakening of potential centres of resistance;
formation of a layer of loyal subjects;
production of a homogeneous "Assyrian" territory;
acquisition of labour;
expansion of cultivated areas.

— Markus Philip Zehnder: "Umgang Mit Fremden in Israel Und Assyrien: Ein Beitrag Zur Anthropologie Des 'fremden' Im Licht Antiker Quellen" (Beitrage Zur Wissenschaft Vom Alten Und Neuen Testament), Kohlhammer: Stuttgart, 2005. (p121–123)

And the main point for the Babylonians remained:

As a political policy, the exile of leaders to distant locations was designed to weaken resistance in the colonies.
— PCB, p71.

That the Neo-Babylonians were less radical in using this method compared to the Assyrians is self-evident: Israel disappeared into ten lost tribes, but Judah remained somewhat more 'unbroken' in terms of (material) culture and the majority of people living there.
For comparison, Sargon boasted in his records that he had deported 27280 Samarians and destroyed the entire House of Omri. (Attested in this number range multiple times, eg (TUAT I/4, 378, 382, 383, 384, 385, 386, 387))
Whereas the bible itself says about the Babylonian deportation toll:

14 He carried all Jerusalem into exile: all the officers and fighting men, and all the skilled workers and artisans—a total of ten thousand. Only the poorest people of the land were left. (2 Kings 24:14, NIV)

Of course, compare that with the number given in  Jer 52,28:

This is the number of the people whom Nebuchadnezzar carried away captive: in the seventh year, 3,023 Judeans; 29 in the eighteenth year of Nebuchadnezzar he carried away captive from Jerusalem 832 persons; 30 in the twenty-third year of Nebuchadnezzar, Nebuzaradan the captain of the guard carried away captive of the Judeans 745 persons; all the persons were 4,600.
— Jeremiah 52 ESV

The exact numbers may be up for speculation. "Tens of thousand" may be an estimate too high. But archaeology confirms that after Nebuchadnezzar went through, Jerusalem itself was for a time uninhabited, with Mizpah taking over the functions of capital for the new province.
To put the biblical account into more perspective, this time to get at the given numbers' reliability from looking at the 'historical and archaeological reconstruction' of the end of the exilic period:

Biblical account Ezra 1–6
Reconstruction

Cyrus issued a personal decree on behalf of the Jews, commanding the return and the rebuilding of the temple
Cyrus issued a general decree, which the Jews could take advantage of

Temple rebuilding was a Jewish initiative

Sheshbazzar brought back temple vessels
Sheshbazzar was probably the first governor of Judah

A large group of 40,000+ returned under Zerubbabel and Joshua
The numbers returning were small, probably a trickle of individuals or small groups

— Lester L. Grabbe: "The Reality of the Return: The Biblical Picture Versus Historical Reconstruction", (p292–308) in: Jonathan Stökl & Caroline Waerzeggers (eds): "Exile and Return. The Babylonian Context", Beihefte zur Zeitschrift für die alttestamentliche Wissenschaft, Volume 478, de Gruyter: Berlin, 2015. Table as excerpt. doi)
That the Neo-Babylonians ended up deporting 'quite a lot' of Judahites in the end was the result of continuous resistance, rebellion and uprisings in the land, often in cahoots with other local powers, like the Egyptians. Something any strategic thinker would have wanted to minimize. So each time there was a rebellion put down, more people were removed from the troubled region. Better safe than sorry? This occurred in 597, 587 and 582 BCE.
— "Judah under the Neo-Babylonian Empire." in: Israel and Empire: A Postcolonial History of Israel and Early Judaism. Leo G. Perdue, Warren Carter and Coleman A. Baker, (eds [PCB]). London: Bloomsbury T&T Clark, 2015. p69–106. doi
— Hans M. Barstad: "Way in the Wilderness. The Babylonian Captivity of the Book of Isaiah The Myth of the Empty Land. History and the Hebrew Bible", Dissertation, The University of Edinburgh, 2010. (PDF)
Comment: @KeithMcClary Well, I'd tend to agree that the Q might be improved to expected standards on H:SE ('documented prior research' etc). But if the first comment now below Q is any indication: then the close vote is based on the voters' false belief that 'the bible' 'has always zero historical value' *and/or* the Q inquires about matters of faith. If that's the case, it simply was closed incorrectlyunjustified. (Add 'what you didn't find', 'where you looked' with an edit to refine the Q, and coupled with a seemingly incorrect CV->  I'd vote RO in an instant.)
Comment: The "ten lost tribes" thing is a bit of sleight of hand in changing their name from "Israel" to "Samaria", don't you think?  It's a bit like people who say that the Roman Empire fell in 476 by referring to it by a different mane for the next 977 years...
Comment: Thanks, I don't understand the close-voters' problem.
Comment: @CMonsour Perhaps I misread your comment, but no, not really. Assyrians took more effort to engineer the region (Sam) where the 10T were. Deporting more and dispersing them more and bringing in a lot more people from outside (influx into Judea was tiny). The initial policy mixed up more ad there was no such cultural dominance asserted by a radicalised 'return-group' (like from Babylon). That region was treated quite differently than in the South, although they also kept some of the religion in place (being then called eg Cuthites, Samaritans). The sleight here is just to demo a greater change.
Answer: I'm going to guess you're coming at this with the idea in your head that every living soul in the country was exiled. That's incorrect.
In fact, while the Bible itself isn't consistent on the subject (and its our only real source), most likely what happened was something much closer to your "I could understand" option. We know the exiled included the King and his court, and quite a few others. We know there were in fact at least 2 deportations (reportedly 5 years apart). We also know it wasn't everyone, because when the exiles came back (after release by Cyrus), they were greeted by resident Jews.
Here's Moore and Kelle had to say on the difficulty of getting an exact number:

Overall, the difficulty in calculation arises because the biblical texts provide varying numbers for the different deportations. The HB/OT's conflicting figures for the dates, number and victims of the Babylonian deportations become even more of a problem for historical reconstruction because, other than the brief reference to the first capture of Jerusalem (597) in the Babylonian Chronicle, historians have only the biblical sources with which to work.

Megan Bishop Moore and Brad Kelle, Biblical History and Israel's Past: The Changing Study of the Bible and History
One thing is does look like we can say is that it looks like the Babylonians took the lion's share of the literate Jews with them. We know this because most of the rest of the Hebrew scriptures written from this point forward were written either in exile in Babylon, or by descendants of those who were. Which explains why it is today so easy to miss the detail that not everyone was taken.
The Book of Ezra does report there were about 42,000 people who returned from the exile in one wave, and about 5,000 in a subsequent wave. However, not all of those people were Jews, and this was 2-3 generations after the exile started, so we don't really know that a similar number were taken. And of course as historians we aren't allowed to take numbers from any one source as ... er ... Gospel, so we have to provide for the possibility that those numbers were inflated (or even deflated).
Comment: I think it's also important to point out that not all Jews took up on Cyrus's offer to return to their homeland in Judea/Israel.  This is significant because Nebuchadnezzar's actions are considered by Historians to be the starting events for the Jewish Diaspora, about 597 BC.  Many Jews erroneously believe that the Diaspora was the result of the Roman's destruction of Israel in 70 AD.  In fact, there were Jews in the Diaspora in Europe even before the start of the Roman Empire.
Comment: @ttonon - In fact I found looking into this that they didn't all go back at once either. This was touched on in the answer. It looks like there were at least 3 waves of remigration.
Answer: In the Bible the word used for thousands - eleph - is also used for small discrete groupings of tribes. So in the passage recounting the demands made by King Nahash at 1Samuel 11.1, it states of the armed force which came to rescue Jabesh-Gilead from the siege of the Ammonite king and possibly friend or ally of David (!); 'the children of Israel were three hundred thousand, and the men of Judah thirty thousand' (1 Samuel 11.8).
As mentioned by others, these numbers are not realistic; the largest empires/ armies of the era such as the Egyptian / Hittite Battle of Kadesh in c.1270Bce were at most 40,000 each side. Furthermore with regard to the Israelite number, there have been no archeological discoveries of any battle-site with such high numbers indicated. It is more likely that a/ the numbers given are symbolic ie hold metaphoric/numerical significance. The proportion of 10:1 making 11 in total is thus of interest. And b/ the term 'eleph' may be interpreted to mean small units of a tribe. Thus Israel had 300 units of around 50 men each representing an area or settlement, and Judah had 30 units of 50 or so men. This brings it to around one-twentieth of the translated value, making a total of around 16,500 men; a much more likely figure.
Re the Babylonian Captivity, the Old Testament makes clear the intention was to prevent further 'rebellion' - thus were all warriors, and metalsmiths in particular removed to Babylon (2Kings 24.14). Some commentators have proposed that Nebuchhadnezzar accumulated philosophers from all his conquered territories in order to force them to provide a way to 'transmute' metal into gold, for his enrichment. Quite a curious possibility. What the Hebrew priesthood and philosophers gained from their time in Babylon, learning the Sumerian /Akkadian and Babylonian cosmologies is another question entirely...


Is there a way to kill weeds in a brick patio without killing the Moss

Question: Does anyone know how to kill the weeds in my brick patio without killing the Moss. I love the Moss that has started growing in the cracks but it is not mature enough to fight off the weeds yet.
Comment: You may find that the moss is actually contributing to the weed problem: they create an environment in which seeds can germinate and over time will lead to the formation of soil in the gaps.
Answer: Most weedkillers intended for use on paths and paving will also kill the moss. However, if your patio receives a lot of shade in winter, but very little in summer, chances are the moss will die out during summer anyway - moss usually starts growing and thriving in cracks when it's mostly shady and damp.
Assuming it won't be in full sun all summer, then you could try using one of these Garden Hand Weeder taking care to avoid the moss:


Are Calculated columns dynamic?

Question: I have got two columns and one is calculating by using the other. But i want to catch TODAY's date and make them calculate with this data. But whenever i change the date , the columns is not changing. How can i do this?
Answer: calculated columns are updated only when you update/edit item.
If you want to have column that calculates exp. Today-2 (two days ago) and to have it everyday fresh, one way to do it is to create task scheduler. Task scheduler will call at some time (you will decide when will it be) powershell script. PS script will go through list and refresh all items but will not update your items, so version of items will not be changed nor will be changed items columns modified by and modified.
I had similar task, here is explanation of solution I implemented, if you want to do it this way.
<code>$web = Get-SPWeb http://Server/ListLocation
$list = $web.Lists["ListA"]

foreach ($item in $list.Items)
{
  $item.UpdateOverwriteVersion();
}
</code>

Are Calculated columns dynamic?


Is it possible to have a full house and straight flush in same hand with only two players?

Question: In Texas Holdem, Is it possible to have a full house and straight flush in same hand with only two players?
Comment: The number of players is irrelevant, unless you're playing by yourself.
Comment: Why would number of players matter, each player has 2 cards added to the 5 community cards. The only way number of players could matter is if there were more community cards based on number of players, or you were asking to make more combinations than the number of players (one player with a straight flush and full house)
Answer: Certainly.
Player 1 : 5♥ 6♥
Player 2 : 8♣ 9♣
Community cards: 7♥ 8♥ 9♥ 8♦ 9♦
Player one has 5♥ 6♥ 7♥ 8♥ 9♥
Player two has 8♣ 8♥ 9♣ 9♥ 9♦
Comment: You can also have Royal Flush and Quad Aces...  https://www.youtube.com/watch?v=XunAlp2azhA
Answer: Yes. I've done it for real at the casino. Made a big score!

The final straight flush: K,Q,J,T,9, all one suit.
I had an Ace Ten off, the Ten made the straight flush.
Another player held pocket pair of Kings to make a K,K,K,J,J full house.

Board ends up K,J,J,Q,9 where 4 cards matched the suit of my 10.


How to execute a command relative to an entity

Question: I was wondering how to execute a command relative to an entity in Minecraft using commands for a map I was working on. I am somewhat familiar with the use of the /execute command, but wanted to use the /summon to make a grenade using item drops or arrows, then have TNT summoned to the area that the item is in.
Answer: The <code>/execute</code> command is used to execute another command relative to something, the syntax you'll need is:
<code>/execute <entity> <x> <y> <z> <command>
</code>
You should use target selectors with selector arguments to select to entity you want to execute from.
To summon TNT from an item drop, you could do:
<code>/execute @e[type=Item] ~ ~ ~ /summon PrimedTnt
</code>
(Be careful with this command, as all item drops will act as a grenade)
Comment: How would I do it for an item with a certain name, such as a snowball with the name "Grenade"?
Comment: @Bookmaster_VP Create a dummy objective (I'll call mine "IsGrenade" as an example), run `/scoreboard players set @e[type=Item] IsGrenade 1 {Item:{id:"minecraft:snowball",tag:{display:{Name:"Grenade"}}}}`, then you can target the snowball items with `@e[score_IsGrenade_min=1]`


Can I damage my camera by shooting directly at a lightbulb in the ceiling?

Question: I got my first dSLR, a Nikon D3500, a few weeks ago. Today I was trying out manual mode and for some reason I thought it would be cool to shoot pointing directly at the lamp/lightbulb in the ceiling while moving the camera. Now I am scared that I might have damaged my camera because I've seen posts about how light can damage your camera. I am sorry if this is a dumb question but I just thought I would ask or else I would keep wondering whether or not I somehow damaged it by doing that.
Comment: Have you tried using the camera since?
Comment: @Mick I have tried using it but I am not sure what a sign of a possible damage would be hence the question
Answer: The direct view intensity of an indoor electric lamp is generally lower than that of a specular reflection (say, from a car window or chrome hubcap) of the sun when outdoors -- but we don't see loud cautions from camera or sensor manufacturers warning against exposing images that might include reflections of the sun.
In practice, there is only one kind of artificial light source that poses a significant risk to your camera sensor: a laser.  Just as you shouldn't look into a laser beam (or even expose your eyes to a specular reflection from a laser above the very lowest power class), you shouldn't take a photo that will have either the direct beam striking the lens in field of view, or a specular reflection of a more powerful laser in view -- I've seen on YouTube where short term exposure to reflections of lasers that can be sold direct to the public has etched permanent color spots (hot pixels) or black spots (dead pixels) on a video camera sensor.
So, don't shoot directly into lasers, or near powerful lasers, or directly at the sun (especially with a fast lens), but don't worry about including a common indoor light bulb in your image frame -- even a 500W halogen won't harm the sensor in a common fractional second exposure, probably not even in a time exposure shorter than a few minutes on a tripod.
Based on comments, to be sure you don't have damage: a damaged sensor would show permanent changes to the values of some pixels.  Most commonly you'd have black or colored pixels in the same location in every following frame, but depending on the damage, it's also just possible you could have something like a faint imprint of the light source visible in a sufficiently low-contrast solid color area in the same part of the frame the light occupied.  I'm confident you won't see this in your described situation.
Comment: Still not a problem.  You'd know if you had a damaged sensor pretty quickly anyway; you'd have permanent black or white (or colored, due to the Bayer array) spots on any subsequent images.  All you did was overexpose enough that all the information from that one frame was overflowed (i.e. every channel of every pixel was all 1, not a zero in sight).
Comment: And the lasers don't have to be visible: https://arstechnica.com/cars/2019/01/man-says-ces-lidars-laser-was-so-powerful-it-wrecked-his-1998-camera/
Comment: Some lasers powerful enough to damage sensors (and eyes!) are installed in outdoor devices like those ones that project a spray of colored spots on a wall around Christmas or Halloween.
Comment: Thanks for the answer. It was more like directing the camera straight up at the lamp in the ceiling rather than just including it in my frame that's why I was worried. Also the photograph turned out just a complete total white canvas and the aperture was f3.8, don't know if that should worry me or if it changes something in your answer
Answer: No, your camera is fine.   You would need to do a long exposure for it to overload the receptors.  You are right though.   Avoid pointing directly into the sun.  It will damage your camera much faster than a light bulb.  If you do damage your receptors you will know it.


Nikon D7000 - image playback always has info bar?

Question: When I first got my D7000 I'm sure that the image playback showed pictures in pure form without information as the default. Now, i always have a rather annoying info bar at the bottom plus the image number in the top right. The display options menu offers no way to remove this so I'm completely stumped. Any advice?
Answer: The playback modes for your camera are summarized on page 165 of the manual:

After taking a picture, the automatic image playback will always show some sort of information, depending on the last Photo Information mode used/selected.
If you want to see the image without any information overlay, press the Zoom In button, and it will show the image only. But that will never be the default view.
Comment: Thank you. It's a bit distracting to be forced to view extraneous information - especially the image number sequence! - but if that's the way it is, there is nothing that can be done.
Comment: Hmm… only having a D5500 I was about to say just press the up button until you find the version with image only… but they really did leave it out on the D7000. Mine has a 7th option, 'none'.


Can a website still detect my real MAC address even if I use different virtual machine each time I visit the website?

Question: Suppose I use a proxy and a different virtual machine each time I visit a particular website, will a website still be able to detect my MAC address and/or uniquely identify me?
Assume that the website owner does privacy violations like inserting cookies etc.
Comment: Unless the website is running some application on your machine (Java applet, Flash, plugin, addon..) it cannot find out your MAC address anyway. Proxied or not, TORed or not, Virtual Machine or not. There are tons of other ways to get close to uniquely identifying you (IP, User Agent, Browser fingerprint, sticky coockies, ..)
Comment: @Adnan why did you edit back the MAC address thing?
Comment: @heinrich5991 Check my comment under Xander's answer.
Answer: The question in the original title of your post ("Can a website still detect my real MAC address even if I use different virtual machine each time I visit the website?") is different than the question in the body of your post.
To the question in the original title:  No, a website should never be able to "detect" your MAC address, under any circumstances.  The MAC address only identifies your NIC on the local network segment, it isn't passed upstream to a website that you're accessing via intermediate routers.
To the question in the post body:  The website many be able to uniquely identify you, and it may not.  There are certainly ways to try and fingerprint a repeat user (cookies, flash cookies, browser profiling, IP address logging, etc.)  that allow for various levels of confidence.  As Rory mentioned, using the same base VM potentially leaves you vulnerable to browser fingerprinting, but eliminates the threat from cookies.
However, To be relatively confident in your privacy, I don't know that I'd bother with the "new VM every visit" and focus on more traditional privacy-protecting measures such as turning off your browser plugins, using your chosen browser's private browsing mode, and most importantly, using Tor.
Comment: @schroeder If it were possible to downvote an edit, I'd have downvoted yours. Instead of removing the OP's misconception form the title, you should have reflected it in the body of the question. This way the OP or any other person having the same misconception would learn from answers like this one.
Comment: I edited the title, which will require an edit of your post.
Comment: @Adnan I was working under the impression that the MAC address was not the main thrust of the question, but rather the ability to uniquely identify. All responses were pouncing on the MAC, and not a deeper discussion of anonymity options. I wasn't removing a misconception, I was clarifying the question to the community.
Answer: MAC addresses are not usually available outside of your local network so that won't be an issue.
If you use a different VM it could be possible to fingerprint you if you're just cloning the same base machine repeatedly (e.g. panopticlick), however if you use different base machines, then the only likely way to identify you (assuming you don't authenticate as the same user of course!) would be source IP addrress, which is an unreliable mechanism as many users may come through the same proxy server.
Answer: Using a different VM means you're using a different computer, so theoretically you're a different person. If they DO identify you as the same individual, they are potentially doing so incorrectly -- or at least would be incorrectly assuming OTHER unique users are actually the same person.
The way they would almost certainly be doing such grouping is by IP address. Multiple VMs probably share the same public IP address, much the same as multiple independent computers on your same private network share the same publicly visible IP address.
Site owners may assume that all visitors from a single IP are actually the same user; they'd do so incorrectly, but in your case they would correctly coalesce your multiple identities into a single user.
And while users sharing a single IP may be unique, they are also typically related in some way, which is why many site owners will link such users anyway. For example, if you get banned from posting new questions on Stack Overflow, that ban applies to all users who share your same IP.
Note that while you said you are using a proxy, if you're using the same proxy every time, you're still the same person. Also, proxies can be detected.
Answer: I believe that a website could identify your mac address by using STUN/TURN protocol via webRTC, see: "Christian Frichot - Hooked Browser Meshed-Networks with WebRTC and BeEF - DEF CON 23 Conference." The video is available on the defcon website or youtube, and eludes to some scary security implications in webRTC


Stress vs Strain for mild steel

Question:
After Yield point on stress strain diagram the under curve occurs what does it mean what will happen for the mild steel at that particular time and again why the curve goes to up and reaches ultimate point  i am not getting that WHY that under curve comes
Answer: I think you're getting confused between stress and engineering stress. As a material has more and more strain, it starts to thin (called necking), and the engineering stress declines. However, measured relative to cross sectional area, the stress continues to increase.
Answer: The physics here get quite tricky. At point E the material has not changed in its molecular structure then there's a small transition gap to point Y. You can compare this gap to the ice to liquid water transition. I make this analogy because from point Y on the material will act like elastic seamy liquid. The other thing that happens is the molecular alignment changes and the material actually gets harder in layman's terms we call it "Forging". This is why the material is getting thinner "necking" yet it takes more force until it gets to the U point. At point U the material is at its hardest and past this the molecular cohesion starts to brake down. After U we apply more force to break it "doted line" in actuality the material takes less force to failure R.

Stress vs Strain for mild steel


Thermocouple keep burning out, is it our gas valve?

Question: Thermocouple keeps burning out. Looking at 1 or 2  within 2 week period ! Tried different brands, the pilot will only stay lit for 3 minutes then automatically shuts down.
Answer: This is not necessarily a thermocouple or a gas valve problem, but possibly just a matter of cleaning or adjustment.  Thermocouples generate an extremely weak current which can just barely hold the gas valve open under normal circumstances.  If you recently replaced your thermocouple, odds are good there is a tiny bit of contamination between the new thermocouple contact and the port on the gas valve where it makes an electrical connection.  The contact between these two needs to be very clean to work reliably.
To burn out a new thermocouple in 1-2 weeks, the gas to your pilot would have to be set much too high and/or the position of the thermocouple would need to be very wrong, and even then I doubt it would fail so quickly.  If you have doubts about what is wrong, your best bet may be to call a professional.


When will the Sword Coast Adventurer's Guide content be allowed on Adventurer's League?

Question: If at all—is there a way to know when the player options in SCAG will be available in AL? According to the latest AL Guide I found, only PHB and few other minor resources are allowed.
Comment: Hmm, I don't know much about AL, so, my question is aiming for something like a timetable/calendar (if it exists) of when released content is "rolled into" official play (which I think is how it worked with Pathfinder Society, not sure how it works here).
Comment: I think you've already answered your own question with that link.
Answer: The Sword Coast Adventurer's Guide is, in fact, already allowed material for Adventurer's League. It does not appear in the current AL Guide because it was published after the current AL Guide. However, AL put out an announcement about it. You should read the link, but:

Everyone, regardless of story origin (season) has the possibility of using the options presented in the Sword Coast Adventurer's Guide. Add the allowed portions of the Sword Coast Adventurer's Guide to the list of allowed rules for every story origin (see below).

Also, note that:

The D&D Adventurers League Player's Guide will be updated with this information next season.

In other words, they're not going to bother with a revised Player's Guide this season, but from next season onwards the Player's Guide will include SCAG as an allowed option.
Comment: To clarify, SCAG won't be listed in the guide as legal material until next season, but is allowed in the current season thanks to the referenced announcement?
Comment: @ObliviousSage Yep. Its omission in the guide is solely due to the guide not being updated to match the current state of AL.