How Can I Stop TNT From Blowing Up?

Question: I have a Minecraft server, and I want to know how to the ban TNT so it doesn't do exploding damage. I have tried Essentials Protect and BanITEM, and did all the config correct multiple times. I tried all the banning items, but when you place TNT it blows up right when you place it.
Answer: To disable mob griefing (basically stop any mob from causing damage to the ground, which includes creepers, the wither, and the ender dragon) type this command in chat:
/gamerule mobGriefing false
For stopping TNT from exploding, it's a little more involved. Basically, you create a hopper loop clock, place any item in one of the hoppers and it should automatically start. Make sure you put a command block on the output (image for the clock is posted here:)

And the last step is to input this command into the command block:
/kill @e[type=PrimedTnt]
And Voila! No more TNT explosions! This command will delete the TNT the second it gets lit, removing it from the game before it gets the chance to explode!
Comment: In recent versions of Minecraft: `/kill @e[type=minecraft:tnt]`

How Can I Stop TNT From Blowing Up?


Was Blaster in Mad Max Beyond Thunderdome supposed to be the big farmhand in the original Mad Max movie?

Question: In the movie "Mad Max", there was a large farmhand character. In the "Mad Max Beyond Thunderdome" movie, Max fights a masked giant in the dome. I have always imagined it was the same character (big farmboy) from "Mad Max" that had managed to survive the apocolypse by way of his brawn (as "Blaster"). When Max unmasks him, Blaster smiles a "No hard feelings" smile at Max. Is Blaster in "Mad Max Beyond Thunderdome" supposed to be the same character as the farmhand in "Mad Max"?
Comment: [Also posted on Movies & TV](http://movies.stackexchange.com/questions/1230/was-blaster-from-mad-max-beyond-thunderdome-the-same-character-as-the-big-farm)
Comment: Here is a link referencing this question, but not exactly answering it: madmaxmovies.com/flubs/othertrivia.html The farmboy actor was Max Fairchild, and was also featured in The Road Warrior.
Comment: I agree. It wouldve been cool to see fifi as Humongous. While fifi was a big guy, the character Humongous seems to have been played by a professional bodybuilder.
Comment: I watched just today (more than 8 years after this question) a sort of documentary about mad max 2 which pointed out that the same extras appear in multiple scenes giving their characters some added depth and this being the same person in both movies would be consistent with that approach. I never thought of this before both reading your question and seeing the video today -- I just assumed that Max took mercy on a mentally-handicapped person. But there is much more to the franchise than meets the eye, that's for sure.
Comment: Dickens used to do stuff like that, at least in David Copperfield.
Answer: Having grown up with the Mad Max series, I firmly believe that "Blaster" was indeed the simpleton that lived with "Aunt May" on the farm in the first movie.
That is why Max spared his life when the helmet came off.  He realized who it was.
Answer: I haven't seen Thunderdome for ages, but my recollection is that the giant is a congenital idiot, and the smile is just an idiot grin. I don't think any special significance was meant by it.
Answer: I never thought about this until I watched Mad Max last night.  I believe it is the same character, not only because they seem to recognize each other in Beyond Thunderdome, but there was some indicative dialogue as well.  Both the Old Lady in Mad Max and Master in Beyond Thunderdome say something to the effect of, "he's only a baby."
Answer: There seem to be a few repeated characters in the Mad Max movies Road Warrior and Beyond Thunderdome only (I don't know of any characters other than Max continue on from the first movie). The pilot played by Bruce Spense is the most notable. Blaster could possibly be the giant that the Biker Gang uses in Road Warrior. They are not played by the same actor though and there seems to be no continuation planned between the two. Blaster and the Biker Gang giant who is listed as Humungus in the script are very similar. I always believed that the injury Humungus received caused the brain damage that led to him becoming Blaster, but there seems to be no documented connection.
Comment: @Gusdor Actually, no. Bruce Spence plays two different (albeit very similar) characters in the two films - The Gyro-Captain in *Mad Max 2: The Road Warrior* and Jebediah in *Mad Max 3: Beyond Thunderdome".
Comment: The large childlike character from the 1st Mad Max movie lived with the older couple that befriended Maxs family near the end of the film. Indeed, the guy in the third movie was called Blaster. I'm pretty sure Humungus died in Mad Max 2.
Comment: *The Road Warrior* was the second "Mad Max" movie, not the original (which was simply called *Mad Max*).  Although I don't recall the large childlike character the OP mentions from *Mad Max*, so I couldn't say for certain you've got the wrong movie.
Comment: I don't believe there are any characters from Mad Max that are continued into the other movies. I'll edit and clarify that there are three movies. Also I don't believe they show Humungus as dead. I think he's just left for dead.
Comment: Humungus was not shown explicitly as dying but he had such a massive car accident whilst in a very exposed vehicle that it would not be credible if he did not.  It would also break the slightly deeper meaning because as good and evil fight over the future (Wez and Max tugging the feral kid back and forth), good wins and evil destroys itself (Humungus kills Wez(?) and himself in the crash).
Comment: @KevinHowell the title character and the aviator are definitely repeated.
Answer: I agree, it seems likely that the only reason Max would have stopped is the sudden pull back to before the apocalypse back to the moments before the death of his family and it pulled that bit of emotion out. I do recall reading about how Goose was originally going to be the Humungus (the burns he got when he was attacked by Toe Cutter and Humungus obvious burns) but one that always got me was in Thunderdome when Max is Underworld talking to Pig Killer. Was the other slave/guy who looked briefly at Max, Charlie from the first one who gets his thoat cut and looses his voice?
Comment: Welcome to SFF.SE. If you have a new question please use the "Ask Question" button in the upper right to post a question. This space is reserved for answers only.
Answer: I have seen all three movies and I firmly believe that not only is
Blaster ("Thunderdome") the large farmhand character
from the first movie, but Humongous could possibly be Fifi, from "Mad
Max." Why not? After Mad Max ended, we didn't see
the other characters again (except for Max).


How to translate "city distance signs"

Question: How to translate in German:

There aren't many of these city distance signs around.

Example:

London 10000km
  Singapore 2000km
Answer: I don't think there's a fixed term for them.
So instead of using a bureaucratic word like Distanzanzeiger or some clumsy noun creation, I'd choose a description.

Es gibt in dieser Gegend nicht viele von diesen Schildern, die die Entfernung zu internationalen Großstädten anzeigen.
Answer: The shortest German term i know for this is

Schilder, die die Entfernung zu Weltstädten zeigen

or for the entire pole with many such sings:

Schilderbaum, der die Entfernung zu Weltstädten zeigt

I cannot deny that this is a relative clause and that therefore some people may struggle with accepting this as a word. (Although when we start into debating word boundaries I might even win that debate.)
Now, for the sake of experimenting, we could try to create one-word-solutions:

Weltstadtentfernungsschild

This would be a working solution, not too long, and unambiguously intelligible.
More beautiful, but perhaps not that practical as not fully self-explanatory would be:

Weltstadtweiser

This impresses through compendiousness and an inner alliteration.
It could be used for the single sign as well as for the entire contraption (pole and multiple signs).
The problem with both of them is that probably the first place where these words have ever been published is... here.
Later thoughts...
I am developing the feeling that perhaps

Entfernungstafeln

might be in use somehow, although it is clearly totally unspecific and could mean a plethora of other things, too.
Comment: How about *Überallhinweiser*?
Comment: Also, *Südpolweiser* does match, because it's the only sort of *Wegweiser* that has the south pole on it.
Comment: "Weltstadtentfernungsschild: This would be (...) unambiguously intelligible." - okay, aber rein vom Begriff her ist mir jetzt noch nicht klar, ob so ein Schild schon im Voraus aufgestellt wird oder erst, während an der Stelle gerade eine Weltstadt entfernt wird ;)

How to translate "city distance signs"


Accidentally deleted page.xml. How do I get it back?

Question: I have accidentally deleted the file app/design/frontend/base/default/layout/page.xml from my directory.
My understanding is that this is the 'default' page.xml file that comes with Magento. How can I get this file back?
Answer: Another way is to just go over to www.magentocommerce.com/download, select the release archive tab, grab the .zip archive for the version you are working with and unzip it into a temp folder. You then have all the files that make up Magento right there stored in the exact same directory tree as exists on your website, very easy to retrieve.
Personally, I keep the archives on hand for the current version, previous version and next version in my upgrade path. That way I always have an easy reference if some code oddity comes up in my custom templates and modules.
Answer: You can get the file from:
http://svn.magentocommerce.com/source/branches/1.7/app/design/frontend/base/default/layout/page.xml
If you have an other version of Magento, you might want to tweak with the version in the URL.
You could also redownload Magento and search for the file in the package if this won't work out.


Installed Apricity OS, but only has barebone GNOME desktop after restart

Question: I installed Apricity OS as guest in my VMware, and installed it successfully.
During installation, the desktop was as Apricity customized. (Fonts, themes, icons, shell, etc.) But when I restarted it after installation, I was greeted with plain GNOME desktop, as attached. Any help would be appreciated.
Answer: When you login choose 'Gnome on Xorg' instead of 'Gnome'.
The issue is that when you choose 'Gnome' it's gnome on wayland (that's still a bit buggy), while 'Gnome on Xorg' uses xorg (that's an old and more stable software).


Can an Apple expert reset or delete my firmware password on 2017 iMac running Monterey remotely or must I go to Genius Bar at store? I have receipt

Question: I can't get to an Apple store. Is there another way to do this. I have my receipt on line for proof of purchase.
Comment: And you wouldn't call Apple because... reasons?  Pick up the phone.
Comment: Hi and welcome to Apple SE! If you'd shorten your title to a briefer description of the problem and lengthen your question with details on what you've tried, specifications, and what you would like an answer about, that would be great and help people to answer your questions in a timely and helpful manner.
Comment: I had a shorter title but my question was closed, said someone else had same question, but it was too basic and answer was n/a…I had serious spinal surgery and haven't been cleared for driving yet so I thought Apple could do this remotely. I want to thank y'all for your help, much appreciated. I've got what I need. This site is awesome. I still have my first Apple SE 30 from the 80s!!
Answer: For sure open a remote support case with Apple. They will review the details and let you know if they can accommodate your request remotely.
I have never had to do this, but my understanding is that you can start the process over the phone with Apple Support, so long as you have proof of ownership.
From Mr.Macintosh:
"How to remove the firmware password with Apple Support.
If you have proof of ownership, Apple can remove the firmware password and retain your data for Mac Devices from 2011-2020. They will walk you through a process (Shift-Control-Option-Command-S) that will show you a code that you can give the Apple support agent. The agent will use that code to send you a file so you can create a USB boot disk that will remove the firmware password."
Do read the whole article.
For a detailed description of how this works Apple EFI firmware passwords and the SCBO myth.
For more recent Macs with the T2 chip, you can do it without Apple Support assistance. Again, read the Mr.Macintosh article.
Comment: Thanks for the technical link.  Fantastic reading!
Comment: It's worth noting that in Apple's view, "proof of ownership" means the original proof of purchase issued when the Mac was first sold by Apple or by an Apple store or by an Apple-approved dealer.


How close does tile need to be to toilet flange?

Question: I'm doing my first attempt at tiling a bathroom floor.  I'm using 2 inch mosaic tiles. I'm trying to minimize cutting.  My question is, how close to the toilet flange do I need to lay the tile?  Could I just use a square outline around the flange so I don't have to cut?  That would mean tile would be no more than 2 inches away from the flange at any point.  Will that work?
Comment: If the problem with cutting tile is the tile saw, look into "tile nippers".
Answer: You want to cut as close to the flange as possible.  Just remember that the cuts won't be seen, so they don't have to be perfectly aligned.
Most toilets have a good 1 to 2 inches from the flange to the outer edge of the toilet bowl.  You want to be closer than that.
Don't forget to get a new toilet seal appropriate for the height of the new floor.
There are many Youtube videos showing the process. Just search on the site for "how to tile a bathroom floor"
Answer: Make the tiles close to the flange. The toilet base has to extend past the tiles. It's a good practice to use a 12" level when adding these tiles to make sure they are level with each other because the toilet will sit on these and you don't want to try and level the toilet afterwards if it wobbles.
Answer: People have (and always will) argue about this but, typically the tile will go down and the flange itself will go on top of it so that the flange sits on the finished floor, but a lot of times the tiles will stop before the flange and be just fine. Especially in older homes that have had their bathrooms remodeled a few times. This is extra handy to avoid drilling through tile and backer board to attach the flange ring to the floor.
The biggest things to avoid are having the "gap" stick out and be visible under the base of the toilet and having a bad seal around the toilet drain that allows water to get at the sub-floor and under the tile, etc. Both are very bad.
A gap between the tile and flange will be OK if you use a taller wax ring that makes up for the difference in height. To ensure a good seal and fill any gap between the flange and the tiles, You need roughly the thickness of a standard ring plus the thickness of the tile floor to make up the difference of the flange being even with the floor surface. They make "extra tall" wax rings especially for this. You don't want a crazy amount of wax in there, but enough to make a good seal. Too much wax could plug the toilet.

How are you cutting your tiles? There's no need to use a tile saw or hole saw for this cut. You can score and break the tiles or use tile nippers to quickly break the tiles on angles quickly and easily. Think hexagon-shaped instead of needing to be a perfect circle. Neatness counts, but there's not a lot of precision cutting going on here.
These older questions may be helpful:

Shoud my toilet flange sit on top of the backer board or the tile of the floor? - There's a nice picture here with a cut-away toilet that shows how the wax ring fits to ensure the seal
What can I do about a toilet flange that is 1/4" below the finished floor?
Securing a toilet flange on top of ceramic tile


What was the Early Church's view of sexual immorality and sex outside of marriage?

Question: What was the early church's perspective of sexual immorality and sex outside of marriage? I know the biblical perspective, but I am incredibly interested in how the early church fathers viewed this issue and would greatly appreciate an answer.
Answer: There is no reason to distinguish between the early church's view and the Biblical view. Acts 15 discusses the Jerusalem counsel, where the Apostle James says:

19 Therefore my judgment is that we should not trouble those of the
Gentiles who turn to God, 20 but should write to them to abstain from
the things polluted by idols, and from sexual immorality, and from
what has been strangled, and from blood. 21 For from ancient
generations Moses has had in every city those who proclaim him, for he
is read every Sabbath in the synagogues."

Later in that chapter, James' words are adopted and given to Paul and Barnabas to disseminate, and Judas and Silas to authenticate:

25 it has seemed good to us, having come to one accord, to choose men
and send them to you with our beloved Barnabas and Paul, 26 men who
have risked their lives for the name of our Lord Jesus Christ. 27 We
have therefore sent Judas and Silas, who themselves will tell you the
same things by word of mouth. 28 For it has seemed good to the Holy
Spirit and to us to lay on you no greater burden than these
requirements: 29 that you abstain from what has been sacrificed to
idols, and from blood, and from what has been strangled, and from
sexual immorality. If you keep yourselves from these, you will do
well. Farewell."

Later in Acts, this is repeated:

25 But as for the Gentiles who have believed, we have sent a letter
with our judgment that they should abstain from what has been
sacrificed to idols, and from blood, and from what has been
strangled, and from sexual immorality." (Acts 21:25)

This would mean that the Jewish definitions and rules for sexual immorality would apply to Gentile believers.
This article comments on the progression of these ideas:
https://www.thegospelcoalition.org/blogs/kevin-deyoung/first-sexual-revolution-triumph-christian-morality-roman-empire/
The article states:

The Christian sexual revolution became codified in law under the reign
of Justinian (527-565).

One earlier source cited is Chrysostom.
Comment: Evidence using quotations from early church fathers, preferably the apostolic fathers, seem necessary to answer this question.  Maybe *Didache* have it?


Does filling your reputation bar with paragon prevent you from filling it with renegade?

Question: If I have played through the game and done a good job of responding to all the opportunities to gain reputation and paragon points then my bar will probably be fairly full and I might have 2 or 3 tick mark levels of Paragon points.
Let's assume that when I play through again in new game+ I want to try the renegade path.  My reputation is transferred from the last play through, does this mean I will still have a full Paragon bar?  If so, will I be restricted from filling my renegade bar somehow or will I encounter more "+reputation" opportunities to that I could have both the P&R bars full simultaneously?
Comment: +1, this is the aspect of the new 'shared bar' that has had me confused.
Answer: Yes your bar will update accordingly.
It's because even though it's hidden, you actually have points (like 100 paragon points etc.) and the bar is just the ratio of Paragon:Renegade:Neutral (the neutral part doesn't appear on the bar, just increases its size).
So you might end a game with 1000 paragon points and 100 renegade points.
Starting a new game plus will keep those scores. If you then finish the game gaining 1000 renegade and 100 paragon, you'll have 1100 of each and be split perfectly.
Answer: You only have 1 reputation bar, and it is used for both paragon and renegade checks. Some of it will be red and some of it will be blue, the ratio will be different depending on which type of reputation you acquire more. If your bar is maxed out, only the ratio will change when you gain paragon/renegade points.
You will have more success while charming/intimidating with a full reputation bar, regardless of whether you're predominantly paragon or renegade. Some interrupts, however, are determined by which (paragon/renegade) reputation is higher, so your Shepard me be more of a pacifict than you'd like if your second playthrough is renegade, but your first was paragon.
Answer: You can change the ratio of Renegade to Paragon. I maxed my bar as 99% Paragon in a first playthrough and I've been playing a New Game + as Renegade, my bar is now at 20% Renegade and I've just reached Tuchanka.
You do keep your full rep bar, and the + neural rep opportunities maintain your rep bar's current ratio, but Paragon/Renegade points will change the balance. Just do every Renegade Interrupt (they still appear even if you're pure paragon) and every Renegade dialog option and you should see your Renegade bar rise.


Referencing Android, using the word 'Android' in a paper

Question: I want/need to use the word 'Android' referring to the Android-System/Software in a paper/thesis. I found these guidelines. Do I have to use both, the TM-symbol AND a footnote? Like AndroidTM - It looks strange...
Comment: You are not required, legally, to use the TM symbol.
There is no need to conform to these guidelines. Many people argue that you shouldn't use these symbols in academic publications: see for instance the answers to [this question](https://academia.stackexchange.com/questions/21521/is-it-mandatory-to-include-the-registered-trademark-symbol-next-to-the-name-of).
Comment: @lighthousekeeper (Also, note that the accepted answer to that question is by far not the most upvoted one.)
Comment: @lighthousekeeper It's tricky to provide a citation for "there is no obligation to do X" -- should I quote the entire laws to prove that there is nothing about X? In any case, here is a citation from an interview to an IP lawyer, speaking about the US law: https://www.forbes.com/sites/work-in-progress/2014/03/12/when-and-how-do-i-have-to-use-trademark-symbols/#cc99963c0afc
Comment: @FedericoPoloni "You are not required, legally, to use the TM symbol." [citation needed] - In fact, the accepted answer to the question you mentioned says that you formally have to use the TM symbol, but in common usage, you rather follow the guidelines of where the paper/thesis is submitted.
Comment: So neither a footnote, nor the TM symbol nor a citation... even if a non-commercial tool is published with the thesis? If I write sth like 'A tool for Android'?
Answer: Your thesis or paper is in this respect similar to a newspaper article about the product ("Independent coverage"). Do newspapers use the "TM" symbol if they write about products? No. (At least no newspapers or magazine I know does.)
It is used by people who have an agreement, are cooperating with the proprietor of the brand name in question, to show exactly that.
These "guidelines" (same as e.g. Microsofts EULAs etc.) are not even a binding contract in many legislations, because they try to force them on you after you have already paid for the product.
Comment: @astronat  They're not, but this is not an academic, but a legal question, isn't it?
Comment: While I think what you say is true, I would be wary of explicitly following the example of newspapers (they are not known for their academic rigour, after all).
Comment: it will not even be publicized.. but i want to be sure doing it right.. i don't think that anyone will care at all.. thank you
Answer: I would advise you to be as conservative as possible and err on the side of adhering to the wishes of the trademark's owner. It won't do you any harm, whereas breaking a rule/convention might wind up giving you grief.
The rights of owners should be respected, especially when the cost is essentially zero. You will want them to respect your IP in future as well.
It is easy to Do the Right Thing when it costs you nothing.
I would guess, however, that mentioning the trademark and its owner once in the paper is sufficient.
And note that you do this, not because of a legal threat but because you respect the people that built the system. This is especially true if their prior work has enabled your own.
Comment: -1 Spinelessness has a tendency to spread ... why would I bow to someone who walks around town with a crown on his head? Because it doesn't cost me much? Because he threatens me? 2x NO.
Comment: @Karl, sorry, your comparison is extremely weak. Not because he threatens me, but because I respect him. Even more because his work has enabled mine.
Comment: These "guideline" imply an legal threat which is completely unfounded unless you are using the name "Android" to advertise a product. Technically, that's imo attempted coercion.


What are Insurance Reserves on The Balance Sheet

Question: Are insurance reserves JUST the amount the company expects (the max) amount it may have to pay in the future for claims.
Or  (B) is it the cash or cash equivalent the company set aside for possible insurance claims?
If (B) why is it under Current Liabilites if the company set aside the money.(Since this "set aside cash" is not under cash and cash equivalents as opposed to debt, where the cash is under "cash and cash equivalents " AND then the debt is under "current liabilites" Though by investment reserves it was never counted as current cash as it is set aside, so why should it be conted as a liability)
P.S the company I am looking at is Lyft
Answer: You'll find the answer in the S-1

Insurance Reserves

We utilize both a wholly-owned insurance subsidiary and third-party insurance, which may include deductibles and self-insured retentions, to insure or reinsure costs, including auto liability, uninsured and underinsured motorist, auto physical damage and general business liabilities up to certain limits. The recorded liabilities reflect the estimated ultimate cost for claims incurred but not paid and claims that have been incurred but not yet reported and any estimable administrative run-out expenses related to the processing of these outstanding claim payments. Liabilities are evaluated for appropriateness with claims reserve valuations provided by an independent third-party actuary. To limit exposure to some risks, we maintain additional insurance coverage with varying limits and retentions. We cannot predict whether this insurance will be adequate to cover all potential hazards incidental to our business.

Liability insurance claims may take several years to completely settle, and we have limited historical loss experience. Because of the limited operational history, we make certain assumptions based on currently available information and industry statistics and utilize actuarial models and techniques to estimate the reserves. A number of factors can affect the actual cost of a claim, including the length of time the claim remains open, economic and healthcare cost trends and the results of related litigation. Furthermore, claims may emerge in future years for events that occurred in a prior year at a rate that differs from previous actuarial projections. Accordingly, actual losses may vary significantly from the estimated amounts reported in the consolidated financial statements. Reserves are continually reviewed and adjusted as necessary as experience develops or new information becomes known. However, ultimate results may differ from our estimates, which could result in losses over our reserved amounts. Such adjustments are recorded in cost of revenue or general and administrative expenses depending on the nature of the reserves.


passing login credentials via iframe

Question: I have two different domains/sites, one http and one https. The http site requires login and then users are shown a non-secure page with an iframe that shows content from the https site.
I would like to seamlessly pass login credentials from the http site to the iframe'd https site. I do not want to use jquery. Is it possible to have the iframe use a POST request instead of GET? I would like to encrypt the login info from the http site and POST the encrypted bundle to the https site.
I'm working with php and apache, if it makes a difference.
I found this article on iframe/POST but wasn't sure how to get the form auto-submitted when the http page loads. Maybe that's a line of javascript? Also, while the login page on the http site has a login form, the post-login page that has the iframe on it does not (currently) have a form. Maybe I could make an invisible form to create this POST request?
Thanks!
Answer: You can use Javascript like this:
<code>document.getElementById('someId').submit();
</code>

passing login credentials via iframe


Is their real difference between photoelectric and thermo ionic current?

Question: All books say only a single photon can remove an electron at a time.
But we see that during thermal emissions electrons are removed by heat waves which are actually infrared rays.
These infrared rays or photons increase the work potential of matter by increasing its temperature, so that even an infrared photon can release electron.
Then must not we say that multiple photons can remove electron?
Answer:
All books say only a single photon can remove an electron at a time

That's probably a misstatement. A single photon can remove an electron, but that's not the only way that an electron can escape. The word "only" is the problem.
There are two different phenomena going on here.
When an object gets warm, the electrons in the material also heat up. You can think of the electrons in a metal as the atoms in a gas - they bump into each other, and all have different velocities as given by the Boltzmann distribution. When the material gets hot enough, some electrons will have so much energy that they can escape. That's a "bulk" property - not a direct result of radiation impinging on the material, but a result of the material heating up. You might say that many millions of photons contribute to the emission, because they contributed to the heating of the target. But that's not what we call the photoelectric effect.
In the photoelectric effect, a single photon can interact with a single electron and give it sufficient energy to escape. You can think of this as "heating up" a single electron to a very high apparent temperature - and it escapes before it has shared that energy with other electrons.
The effect is definitely real - you will see photo-emission for photons with sufficient energy (short enough wavelength, corresponding to the energy needed for electrons to escape) and it will exist regardless of the intensity of the radiation - in other words, it doesn't require you to heat up the cathode in order to see the emission. Einstein got his Nobel prize for figuring this out.
Answer: Thermal emission is really a different process, driven by phonons not photons.  Phonons are the vibrations of the crystal lattice itself.  But more specifically, an intense coherent infrared light source like a laser can be used to eject electrons.  See for example: http://www-ssrl.slac.stanford.edu/spear3/documents/schmerge_multiphoton_emission.pdf
Comment: Good point about multi-photon interaction. I didn't think that's what the question was about - but you may be right.
Comment: But even phoyons require photon as energy source.
In photo electric effect a photon is given with such phoyon energy that electron escapes out vibrating.


Is there any online server to upload recommendation letters and share the link with the universities

Question: Usually we need a few recommendation letters when we apply for a job or academic positions. Im wondering if there is any online server to make it easier on my referees so that they only write once their letters and later I only share the link with the companies or who asks for a recommendation.
Any suggestion is welcome.
Comment: How can your referees be sure that you won't be able to see the recommendation letters?
Comment: that is the open point. is it so critical that I dont see? I must not be able to edit though
Comment: @Srteve Many referees will expect confidentiality, since a reference is supposed to be an honest evaluation of you. If you are able to read the reference, your referee may feel pressured for social or legal reasons to omit negatives from it, and the recipient of the reference may suspect such a thing has happened even if it hasn't!
Answer: In mathematics there is, and it is used by most research-oriented departments for hiring: MathJobs. Hiring departments pay (i.e., not candidates) and candidates indeed cannot view the recommendation letters.
It is extremely efficient, and in my opinion this system deserves to be more widely imitated. Note however that this is used at the option of the hiring department, and not the job candidate. So in particular you can't use this system, except for positions advertised via this site.
In your situation you might be able to use Interfolio, but I'd check with prospective employers (or your advisor) before using this.
Answer: Yes, it's called:
 https://www.interfolio.com/
And you can't see the letter, as they validate any request. Works quite good.
It's not free though.
Answer: Authentication is an important aspect of references and letters of recommendation. If the letters were uploaded to a third party site what assurances would the recipient have that they were genuine? If they just had to click on a link on some site there is a great deal of potential for fraud. Anyone could upload anything purporting to be written by anyone.
People will just start writing and uploading their own letters.
Most reputable employers and universities would expect a letter to come direct from the writer or to be uploaded to their own systems using authentication supplied to the author.
Comment: Then how to deal with asking the referees to send multiple recoms to different email addresses? I feel rather embarrassed.
Comment: @Srteve You shouldn't feel embarrassed. Writing and sending references is part of a senior academic's job, and it is expected that you will ask them to do it.
Comment: Not necessarily. As I wrote in my answer, there are good solutions for the authentication problem.
Answer: That is a good idea, however, such letters won't be specifically addressed to (for instance) University X or Prof. Y. They would be generic letters. Most institutions prefer letters addressed to them (hence, they are using the current system).
Comment: I think it is still ok if the letter starts with "Dear Sir/ Madam"
Comment: I never said it was not ok, but rather "most institutions prefer it to be addressed to them" :)
Comment: I'm not sure it makes a difference. People now have to send dozens of letters, and so they can't expect the references to address each and every school specifically.
Answer:
Im wondering if there is any online server to make it easier on my referees so that they only write once their letters and later I only share the link with the companies or who asks for a recommendation.

I was recently in a position of asking multiple professors for letters of recommendation for applying to grad school. I had about ~8 applications, so ~8 letters from each professor. All of them were happy to send them through the standard protocol (through the application website). I think the case for applying for a job or any other academic position should be similar in this respect; your referees will understand that you are applying to multiple places and will not be bothered by the request for multiple letters.
To be on the safer side, you should explicitly tell them roughly how many places you will be applying to, in case they would like to slightly tailor the letter for each application.
Lastly, follow the relevant tips in the answer to "How do I effectively solicit a strong letter of recommendation from a professor?".

From your comments:

that is the open point. is it so critical that I dont see? I must not be able to edit though

This depends on the referee. Some might want to keep the letter confidential while others wouldn't mind freely sharing the letter with you. Here is one case where the student's professor did not write a letter since the right to view the letter was not waived.

Then how to deal with asking the referees to send multiple recoms to different email addresses? I feel rather embarrassed.

Don't feel embarrassed. Just ask.

As has been pointed out in another answer, the authenticity of the letter partially (if not fully) rests on the email address it came from. The letter is of little use to the university/company that you are applying if they cannot be confident of its authenticity.


how to change a file in user mode and not in root mode in RHEL6?

Question: There is a common file which is accessed by both root and user.i want to change that file from user mode and that should not effect root and viceversa. how to do this in RHEL6?
Comment: Have you tried setting and ACL on the file? `setfacl -m u::rw` replacing `` with the user you're targeting.
Comment: @JoelDavis No that i didn't try. i have two desktops like gnome.desktop and custom.desktop, now i want to allow gnome.desktop only in root mode and not in user mode. similarly i want to allow custom.desktop in user mode and not in root mode.when i am changing custom.desktop or gnome.desktop it gets affected in both modes. that is the problem i am facing.
Comment: Unless you do something with `pam_cap` to lock root out of CAP_DAC_OVERRIDE (which wouldn't be advisable), root can (by design) do whatever it wants. root is the failsafe account you're supposed to use to back yourself out of any precarious position you accidentally put yourself in.
Answer: sudo does the job for me .
Just prefix sudo before the command .For example to change access type
<code>     sudo chmod +x filename
</code>
Answer: It sounds like you want different users to see different contents for the same file. This is not possible.
(It is possible to let different sets of processes see different contents for the same file. But this takes a lot of effort to set up.)
Many applications look for a configuration file in the user's home directory. This is the usual way to obtain different behavior for different users. Failing that, you might use environment variables or command line options.
If you're having trouble doing something, ask how to do it. Don't rush into some oddball solution and ask for help implementing it. You're suffering from the XY problem. Ask about your ultimate goal, not about a dubious intermediate step.


Add the same multiplier to one object

Question: I'm sort new to blender, just discovering and set off to modelling something of my own, best way to learn a software for me rather than just following tutorials. While working on this part I was wondering whether there is a way to automate adding the same multiplier to one object multiple times. In this case I'm making a bracket and for the screw holes I'm using Boolean. However since there are many holes its kind of cumbersome going 1 by one and its taking a silly amount of time. I am more used with CAD and parametric software (such as grasshopper on Rhinoceros) so I'm wondering if there is a better way to do this bracket.
Comment: if i may give you a hint: you should definetely not try to find out everything on your own with Blender, because it doesn't work intuitive at all. You should watch tutorials because your learning curve will be multiple times steeper. Blender is neither always logic nor working in the same way (just it works on one way with that modifier doesn't mean it works on the other e.g.) so...if you don't want to get frustrated you should watch tutorials. Blender is really an amazing great software but...i think it needs tutorials to learn it.
Answer: You can put the objects that you are going to cut with into a single collection and use that collection as the operand type for the boolean modifier.

(Remember to use Shade (Auto Smooth) after using the boolean or else it will give you some wierd shading artifacts)
Comment: Thank you for your answer! I'll try it and seems like a more efficient way than what I did! ^^

Add the same multiplier to one object


Can't boot Ubuntu from CD/DVD or Flash Drive

Question: I have a Dell Dimension 4500 with Windows XP on it.  I wanted to boot Ubuntu from a CD/DVD or my flash drive, but I can't boot it from the CD/DVD I created or the flash drive.  The CD/DVD will not boot from the DVD drive (you can only view DVDs with this drive) or the CD drive (because it is a DVD). The computer does not recognize my flash drive as a removable drive.  What other options do I have? Can I install directly over Windows XP, or try to request an installation CD from Ubuntu?
Comment: What version of ubuntu did you download, is it some 64bit Ubuntu? Do you run WinXP 32bit? I am asking because I know you cannot install 64bit Ubuntu on your machine or 64bit WINXP for that matter. I have a Dell Optiplex machine, not very different from yours, and i'am doing ok as long as I keep using Ubuntu 32bit, any version of it.
Comment: Try the install on a different computer if you have one. If that doesn't work request or buy a installation cd from Ubuntu. When I installed Ubuntu all I did was boot up the computer and delete the ubuntu rom and it brought me to the installer. You can't install over Windows.
Answer: you need to enter the bios and select the deviceto boot. you can enter the bios on most computers by pressing f2 at the post screen.
The post screen is the screen displayed when you turn the computer on, it displays the manufaturer name, computer model, and in most cases the key used to enter the bios...
for my asus k55a the process for booting a cd is as follows

press f2 at post to enter the bios
navigate to the boot menu
set the cd/dvd drive as the first boot option (at least before the internal hard drive)
navigate to the menu that includes the option "save changes"
reboot

if all worked out, then the pc should automatically boot the device you put at the top of the list. if no device is found to be bootable there, it will move to the next in the list. keep in mind that to boot from the hard drive, you must change this setting once you no longer need it configured as such, or you must remove any bootable media that is placed in the list before your hard drive
you may also press f12 on most PCs to get a menu of available devices and select what to boot from. this will override the settings in the bios and boot from the selected device.
Here is a youtube video demonstrating how to do so...
https://www.youtube.com/watch?v=k0Hkr2sNZ8k
keep in mind that your PC may have a different key that must be pressed to enter the boot menu / BIOS... This is USUALLY displayed at post but you can try the following keys if f2 and f12 dont work (f1, f2, f11, f12, del)
if it still doesnt work find a manual for your model of PC... the manual will tell you which key to press
if it STILL doesnt work, you most likley have not prepared your bootable media properly. please follow the steps provided by the ubuntu website exactly:
http://www.ubuntu.com/download/desktop/create-a-usb-stick-on-windows
Notice
Ubuntu IS NOT WINDOWS... windows programs such as Word, Photoshop, and internet explorer will not work with ubuntu. Alternatives are provided and some programs such as firefox are compatible, but bear in mind that you WILL need to re-learn nearly everything you think you know about computers before Ubuntu can be an effective alternative to windows


Slow folder opening due to folder scan in XFCE

Question: Is there a way to turn off background folder scan when opening a "Home" icon on XFCE desktop?
This takes time due to a lot of files in home folder (source repos, why not).
Answer: I do following steps and it works for me:

Open /usr/share/gvfs/mounts/network.mount this file using an editor: sudo nano /usr/share/gvfs/mounts/network.mount
change AutoMount=true to AutoMount=false.
Save file and login again.

This will stop Thunar stating the Network every time you run it.
Have a nice time.
Answer: For starters, if your computer is up to date you can already speed up the first start up of Thunar by adding it to your startup applications.
In Session/Startup you can add a new app, call it Thunar maybe ;) and in the command field you can put /usr/bin/thunar --daemonso it will start in the background and be faster when you call a window.
Be careful not to "Save Session" on shutdown with this enabled, this will start a thunar for every-time you shutdown this way and will cause problems.
Answer: It might be the thubmnail generator, tumbler. what-is-tumblerd
I removed it from my install because it was causing folders I open to task the CPU, and delay because it is making thumbnails for every file.
How to remove:
With Synaptic Package Manager:
Search for tumbler click on the check box for it and select "Mark for Removal"

With Terminal:
sudo apt-get remove tumbler

Note: Removing tumbler will ask you to remove xubuntu-desktop this is ok since it is a "meta-package" and will not remove xubuntu, https://help.ubuntu.com/community/MetaPackages
Comment: How did you remove it? If I try to apt-get remove it, it tries to remove xubuntu-desktop package too. :|
Comment: yes, that is ok, xubuntu-desktop is a meta-package, http://askubuntu.com/questions/66257/what-is-the-difference-between-a-meta-package-and-a-package , you can remove it. "removing a meta package does NOT remove the packages it installed" , https://help.ubuntu.com/community/MetaPackages


Wordpress Custom Fields and Images that don't exist

Question: I have a page (http://schroeder.s482.sureserver.com/york-family-farm/) that is a photo gallery generated from uploaded photos using the Advanced Custom Fields plugin.  There is only one photo in this particular page, but other pages could have up to 21 photos.  Is there a way to have it only show images that are actually there?
Here is the code that I'm using to display it:
    <a href="<?php the_field('featuredimage'); ?>" target="_blank">
    <img src="<?php the_field('featuredimage'); ?>" width="290px" height="217px" id="ffs-pic">

Thanks so much!  Love learning from you guys!
Answer: I'm guessing 'featuredimage' is a field you created yourself using the Advanced Custom Fields plugin.
Assuming that's the case, you have a few choices.

Still using the free version, you can create 20 more image fields and name them 'image2', 'image3', 'image4', etc... Then insert them into your template the same way you are displaying 'featuredimage'. This has the obvious downside that you have to manually create everything, rather than looping through your images and generating the HTML programmatically.
Buy one of his add-ons like Gallery or Repeater. They are meant for this sort of thing, and will save you a lot of work.

Let me know if any of that didn't make sense.


What are the chances my visa will get accepted

Question: I'm a 15 year old syrian travelling to Greece with my mother and 2 sisters who are younger than me, we have booked in Athens  for one month and also flight tickets prior to applying, we're arriving there with 30,000€, we've submitted the employment details and travel insurance, what are the odds we'll get rejected? , we traveled to Europe under a schengen visa in 2016 before
Comment: Are you planning to carry €30,000 in cash? If so you must declare it on arrival in Greece (and possibly on departure from Syria). Expect to be questioned on the provenance of such a large sum.
Comment: We can't predict the odds, but having previously had a visa counts in your favour unless your family's circumstances have changed significantly since 2016.
Answer: We cannot tell you the odds. But some things would appear alarming to a visa official unless your explanation was unclear.

Bringing €30000 for one month would be rather unusual. Few tourists spend that much. Having that much money at home and bringing only a small part is better.
A stable job with income in excess of expenses is much more important than the money at hand.
Comment: I think carrying that amount of cash, even if planning to spend less, would itself be a red flag for a visa officer.
Comment: @David, edited.


How to replace the System's Download folder with one in an external drive?

Question: When you open finder, there is a download folder with a unique icon. I'd like to move that folder to an external one and force the system to recognise that new location.
Comment: There's no global setting for the Downloads folder. Each app that saves to it does so because the app's preferences are set to it and can be changed to any location within the app's preferences.
Comment: @user3439894 But any normal folder would not have the down arrow icon.
Comment: I have a downloads folder on most of my external drives and they have the same icon as the Downloads folder in my Home folder because I assigned that same icon to them. You can do the same, this has been covered on the Internet enough you shouldn't have any problems finding directions. Then put an alias to the external Downloads folder into the Downloads Folder in your Home folder. Set the download location in your Browser(s) to the external location if you want. Personally I don't because my external drives are not always connected.
Comment: As to the icons in the Sidebar of Finder, even if you changed a generic to a custom one, the info will be short-lived because, it's overwritten when Finder updates is settings, which is done often. IIRC it was with Mac OS X Lion that Apple essentially said the User is no longer allowed to mess with Finders appearance beyond what we program it to be. I'd talk to Apple about it, but I do not believe Apple is going to change from the direction they gone! They don't want Users messing around with the core elements of the UI, beyond how they define them to be
Comment: @user3439894 Can I link the current downloads folder to the one in external? In this way i can retain the icon as well as functionality.
Comment: If that could be done, while keeping the custom icon in the Sidebar, I would have already mentioned it.
Comment: Airdrop is broken for me after symlinking to a folder on an external drive. I see user Josh Hibschman's suggestion: How do I add the "chmod -h 700" to an existing symlinked Downloads folder on an external drive? Do I just enter "chmod -h 700 ~/Downloads" into Terminal — or no I need to reference the symlinked location on the external drive? Thanks!
Answer: This is possible via symbolic link.

Move your existing data in ~/Downloads to the location you want, let's say /ExternalDrive/Downloads

Open Terminal and run:
This will remove the Downloads folder and you'll need to type in your password to do that (you won't see *** when entering, just hit enter after you finish).
sudo rm -rf ~/Downloads

Create a symbolic link to your desired location:
ln -s "/ExternalDrive/Downloads" ~/Downloads

And voila! Dowloads folder moved.
A more detailed version of this process can be found here.

It's also possible to create a link to the iCloud Download folder. Using this command:
ln -s /Users/yourusernamehere/Library/Mobile\ Documents/com\~apple\~CloudDocs/Downloads  ~/Downloads

The main caveat of this solution is that macOS will not recognize the symbolic link as the official macOS Downloads folder, so the icon used in the favorites sidebar will not be the usual download icon () but rather the normal folder icon ().
Comment: should add a `chmod -h 700 ~/Downloads` to make the symlink's permissions equal to the old Downloads folder (fixes issues with shortcuts, system services, airdrop)
Answer: Your question doesn't specify whether you're just interested in changing the default Downloads folder location for your web browsers, but since web browsers are the most common way that users download files from the internet, below are instructions on changing this location within Safari, Firefox and Chrome.
Safari
For Safari:

Go to Safari > Preferences (or just press command,)
Make sure you have the General icon (top left) selected
Find the File download location drop-down menu and select Other... from your list of choices
Navigate to and select your preferred Downloads folder location
Exit Preferences

Firefox
Very similar to Safari, in Firefox:

Go to Firefox > Preferences (or just press command,)
Make sure you have the General icon (top left) selected
Under the Downloads heading you'll see a radio button labelled as Save files to with a field next to it. Click on the Choose... button
Navigate to and select your preferred Downloads folder location
Exit Preferences

Chrome
Finally to Chrome:

Go to Chrome > Preferences (or just press command,)
Scroll to the bottom of the window and click on Advanced
Now scroll down further until you see the Downloads heading
Click on Change
Navigate to and select your preferred Downloads folder location
Exit Preferences

NOTE:
Similarly, others browsers and 3rd party downloaders also provide a setting in their preferences from which you can choose your Downloads folder location.
Comment: How can I change the icon in Finder to the down arrow as well?
Comment: Within the Finder follow these 4 steps: (1) Select the macOS default Download folder and go to File > Get Info. (2) At top left of the Info window, click the icon and then go to Edit > Copy. (3) Select the other folder you've set up to be your Downloads folder and then go to File > Get Info. (4) Click the icon at top left and then go to Edit > Paste.


How to establish homebrew server connection

Question: HOST
First, my host is dreamhost. I have root access. The system is a linux system.
SERVER
**UPDATE: It looks like the server uses modsecurity (modsecurity.org). I'll look into it more now, but if anyone has any tips or knows how to work with it, that's where I'm stuck now. **
Second, I wrote a java server that binds to port #### and the listens for connections. I can run this local & connect, but I'm trying to put it up on my server and connect from anywhere. That is the idea behind a server.
<code>    private int port;
    private ServerSocketChannel ssc;
    private Selector selector;

    public Server(int port) {
        this.port = port;
    }

    public void run() {
        try {
            ssc = ServerSocketChannel.open();
            selector = Selector.open();
            ssc.socket().bind((new InetSocketAddress(port)));

            new Thread(new ReadLoop(selector)).start();
            new Thread(new AcceptingLoop(ssc, selector)).start();

            System.out.println("Bound to port " + port + " and awake:");
        } catch (IOException e) {
            System.out.println("Server could not start.");
            e.printStackTrace();
        }
    }
</code>
I launched this on the server. The program says it successfully bound to the port.
CLIENT
The client is flash, AS3. Here's the code i use to attempt the connect:
<code>var mySocket:XMLSocket = new XMLSocket();
mySocket.connect("http://mydomain.net", ####);
</code>
I'm well aware of the sandbox policies. This is something else. I receive this error:
IOERROR [IOErrorEvent type="ioError" bubbles=false cancelable=false eventPhase=2 text="Error #2031: Socket Error. URL: http:--mydomain.net"] (replace -- with //, stackoverflow was reading it as a link)
This error apparently means that Flash never found a server. I would have gotten a security error if it had been the sandbox.
Anyway, how do I tell if ports are open correctly, if they are blocked, etc?
I'm also wondering if this has something to do with it:
http://wiki.dreamhost.com/Mod_security
I unfortunately don't understand a lot of this stuff, but I'm trying to learn.
Comment: can you connect from the command line of the client machine ? If the client machine is windows you should open a command prompt and run telnet mydomain.net #### (your port). This will try to open an connection to your server. If this works then something is broken with the flash setup. If not then you need to look at the network setup  on the server side.
Comment: I cannot connect that way. Recieved:

Could not open connection to the host, on port ####: Connect failed
Answer: Try and run your server program on a port that is unlikely to be blocked (e.g. 80, 443). Of course, make sure that nothing else is using the port that you choose.


Is there a directory of precise dosages of fertilizers for indoor/outdoor plants?

Question: For example, I have a lot of plants inside (African violet, geranium, coleus, etc.) and outside (dolichos, petunia, pansy, asters, etc.) my home. Also, I have a lot of chemicals (such as ammonium nitrate, magnesium sulfate, ammonium molybdate, etc.) that can be used to compounding or correction of fertilizers. But I found only individual science research for geranium or petunia (for example). Is there a directory of precise dosages of fertilizers for indoor/outdoor plants?
Answer: No, I'm afraid not. Because plants vary in their requirements in terms of fertilising, it's more usual to start with the plant you want to feed and check what it requires in case it's anything particular (orchids, for instance, have specialist feeds available). At a very simplistic level, feeding also differs depending on the results you want - for instance, you mention Coleus, which is usually grown for its decorative leaves and not for its flowers, which would mean a fertiliser with a higher N level than K is more appropriate, whereas a plant grown for its flowers might do flower better with a different formulation. I'm not sure how you'd source the full readout of NPK plus trace elements required for every plant, nor do I believe any such resource exists for all flora.
Because it's quite a complicated area, proprietary brands of different feeds are available, ready mixed, with or without trace elements, because unless you're a chemist as well as a horticulturalist, working out precisely which chemicals to mix for different plants would be extremely difficult. I imagine its possible you have some sort of chemistry background though, if you already have the chemicals you mention available.
Comment: @AleksandrVishnyakov - well hopefully I understood your question - the real question, though, is did you understand my answer? Oh dear, your comment has now disappeared, rendering this response irrelevant...
Comment: I apologize for my English.
Of course, plants has a different requirements in different places, growing habitat and result. But any plant has a specific requirements and optimal values. For example, streptocarpus need ammonium nitrogen, instead of nitrates like many other plants. Coleus (here you're wrong) need a high dose of K, if you want to get colorful leaves (I use NPK 2:1:4) and less P to prevent flowering (but it need high N and P at start). I just think, that scientists, who grows plants for experiments/in vitro, has a something like databse with optimal values for macro/micronutrients
Comment: I just press Enter too early ;)
Comment: @AleksandrVishnyakov - I meant less K in relation to N re Coleus, but never mind. There may be resources for some plants (you've found some already) but it won't be for all flora. If you find that kind of 'bible' I'd be interested to hear about it.


How Do DB Version Control Systems Lack in Script Semantics When Modeled on Source/Target Difference Comparisons

Question: There are several database version control solutions out there to assist with controlling not only the versioning of a database, but also deploying and synchronizing databases. These systems are typically based-off either a "source/target difference synchronization" model, or a "direct application of migration scripts" model. My question is around the source/target difference synchronization model.
In this model, you essentially take a snapshot of a source database (your basis of record) and run a comparison of this snapshot against a target database. The tool ideally will create the necessary scripts to synchronize the target database to have the same structure (and reference data) as the source database. One of the disadvantages of this model is that the tool might not be smart enough to capture the exact semantics of the database changes that were made, and will create "bad" scripts.
Are there any good examples of what a "bad" script is? I am failing to see why this is a disadvantage. For example, if I drop a column on a reference data table and then re-add it, I end up with a table with the same structure, but would have null (or default values) in the the re-added column. A synch tool might generate something like:
UPDATE table SET re_added_column = null where pk_column = <val_1>;
...
UPDATE table SET re_added_column = null where pk_column = <val_n>;

While the following might be more efficient (and represents exactly what happened):
ALTER table DROP COLUMN re_added_column;
ALTER table ADD COLUMN re_added_column;

In the example, however, I fail to see why this difference would be an actual cause of concern. Is it just that the former is "dirtier?" Are there any examples where there would be an ACTUAL problem with this behavior?
Answer: Dropping the column would remove all values from all rows of the table.  If the change applies to all rows that could be in the database this might be acceptable.  If the model tables are for a base set of records, it is possible the DROP COLUMN would drop data from other records.
The DDL (Data Definition Language):
ALTER table DROP COLUMN re_added_column;
ALTER table ADD COLUMN re_added_column;

Is somewhat equivalent to the the DML (Data Manipulation Language):
UPDATE table SET re_added_column = null;

However the DDL solution will move the column to the end of the row.  This column position may be sub-optimal.  The DDL solution may also require removal and recreation of Indices and Constraints.


How can I have search results fill the page?

Question: I created my own search function on our website. It uses a simple php script that searches through our database to find what the users are looking for. The search results page doesn't fill the width of the page and the results are displayed vertically, one by one.
The code that displays the results.
        $count = 0;
        while($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
            $t = $count%3;

            echo ($t == 2) ? "
" : "
";
            echo "
";
            echo "";
            echo "
";
            echo "
".$row['title'] ."
".$row['isbn']."
";
            echo "
";
            echo "
";
            echo "Start Reading";
            echo "
";
            echo "
";
            echo "
";
            echo "
";
            echo "
";

            $count++;

How can I get the results to fill the width of the page?
Comment: Any reason you can't use tables?
Comment: No reason, I'm new to web dev and didn't know about tables. I'll be looking into it, thanks for the advice.
Answer: It seems you are using Bootstrap CSS framework. If you want to keep using that, you might want to understand how the grid works by reading this page: https://getbootstrap.com/docs/4.5/layout/grid/
I didn't test your code, but the fact that you are using the class col-md-4 is probably why it's not taking the whole width of the page (the result depends on the parent container of the code you are generating, which you didn't show).
So go ahead and remove the class col-md-4 to see what happens.
Comment: Thank you for your advice, I was able to solve it. There was no row class surrounding the while loop that was printing the results, and once I included that it worked the way I was intending.
Answer: I think that you have a few experiece working with the front-end or client side (html, css, javascript).
I see that you only uses div containers, i recomend you see the diferences between inline and block html's elemtens.
The div is an block element that always starts on a new line and takes up the full width available.
An inline element does not start on a new line and only takes up as much width as necessary. An example is the span tag.
You should read these articles:
https://www.w3schools.com/html/html_blocks.asp
https://developer.mozilla.org/en-US/docs/Web/HTML/Inline_elements
Also i recomend you to learn how to use the navigator console that show you the with and height of all of your html tags and more util information.
Comment: Thank you for your advice, I was able to solve it. There was no row class surrounding the while loop that was printing the results, and once I included that it worked the way I was intending.


What directory does homebrew use to build programs?

Question: I would like to change the directory that homebrew uses when it builds programs
Is that possible? I didn't find such option in brew command
Answer: When you install a Homebrew package, if it needs to compile it from source, it will extract the files to /tmp/package-XXXXXX and compile them there before installing to /usr/local/Cellar/package.
You can specify a different temp folder by setting an environment variable...
export HOMEBREW_TEMP=/Users/USERNAME/Desktop/temp

Answer: The manpage of Homebrew version 0.9.9 suggest something different:
the default folder Hombrew uses to do its things (including compiling) is ~/Library/Caches/Homebrew, and you can change it by setting HOMEBREW_CACHE environmental variable. The environmental variable can be set by editing the hidden file .bash_profile in the user folder, e.g.:
nano ~/.bash_profile

then add
export HOMEBREW_CACHE=/path/to/folder

Remember to do a source ~/.bash_profile to load the new environmental variable in already opened terminal sessions.
Brew manpage about HOMEBREW_TEMP:
HOMEBREW_TEMP

    If set, instructs Homebrew to use HOMEBREW_TEMP as the temporary directory
    for building  packages.
    This  may be needed if your system temp directory and Homebrew Prefix are
    on different volumes, as OS X has trouble moving symlinks across volumes
    when the target does not yet exist.

    This issue typically occurs when using FileVault or custom SSD configurations.

Unless this fits your settings, you should avoid setting HOMEBREW_TEMP.


Type with $X\rightarrow X\cong X + 1$

Question: In the article Voevodsky's Univalence Axiom in Homotopy Type Theory, an example is given of how types are not like sets: the existence of a nontrivial (nonzero) type $X$ such that  $X\rightarrow X\cong X + 1$. However, I am unable to find this counterexample in the references in the article. Does anyone know this example? Is it a special case of some more general universal property, like maybe a type $X$ with $Y\rightarrow X \cong Y +1$ for all $Y$?
Comment: The following should morally be an example, but I don't know how to make it precise (I read some things about it once but the details were way more complicated than I expected). Find a topos, something like a topos of computable functions, where $\mathbb{N}^{\mathbb{N}}$ consists of the computable functions $\mathbb{N} \to \mathbb{N}$. These can be computably enumerated, so $\mathbb{N}^{\mathbb{N}}$ should be computably in bijection with $\mathbb{N} + 1$.
Comment: (I think the reason the details were more complicated than I expected is the following. The above line of reasoning suggests that $\mathbb{N}^{\mathbb{N}}$ should even be computably in bijection with $\mathbb{N}$. But if this is the case then the Lawvere fixed point theorem implies that every computable function $\mathbb{N} \to \mathbb{N}$ has a fixed point, which is clearly false. I think some fiddling around with partial functions is necessary to fix this. Probably Andrej Bauer knows the real story here.)
Answer: I'm not ready to venture into homotopy type theory yet, but there is an example in topos theory, which might be transportable into the context you want.  In the object-classifier topos, the generic object $U$ satisfies $U^U\cong U+1$.  This is Example 1 in an old paper of mine, "Functions on universal algebras" [J. Pure Appl. Alg. 42 (1986) 25-28].
Comment: As I understand it, homotopy type theory is supposed to be the syntax of e.g. $(\infty, 1)$-topoi and so in particular should be interpretable in any ordinary topos.

Type with $X\rightarrow X\cong X + 1$


How can get a quassel-client and quassel-core irc setup and running?

Question: I want to use quassel to access my irc channels from multiple laptops, and want to know how to get it set up. I have a server I will install the core on and several laptops that will run the client. How can I get the perfect quassel irc setup?
Comment: Appologies, I don't have the reputation to comment on the previous answer, but the link is dead. Here is a link to the cashed version: http://webcache.googleusercontent.com/search?q=cache:v4T5AaLDhUIJ:www.ubuntu-tennessee.org/2009/tutorials/using-quassel-in-a-client-core-setup/+&cd=2&hl=en&ct=clnk≷=uk
Answer: On system with quassle-core installed, I ran the setup via GUI (found this out when started CLI setup)

Start client (not stand-alone) and configure core setup
Create admin account
Configure IRC servers

On other client, I did the following:

Install Quassel client
Configure to connect to Quassel core

Here are older directions that do not use the GUI: http://www.ubuntu-tennessee.org/2009/tutorials/using-quassel-in-a-client-core-setup/


How to connect a 4x4 keypad without a microcontroller

Question: I have the RS 331-304 4x4 keypad, and I need to connect it so that I can determine which key has been pressed without using a microcontroller. Is there a way I can connect it using logic gates? The final aim of connecting it is to determine which number has been pressed, decoding this value into BCD and storing it in an array of D Flip Flops. I can't see how to go about connecting it, and would greatly appreciate your help.
Answer: You could just emulate what a micro would do, using logic gates. For example use a 2 bit counter/decoder and clock to select a column (1 of 4) and read the 4 rows in parallel.
If only one key will ever be pressed at once (or at least only keys from a single column at once) then this will work without a diode per key.  A micro has the same limitations.
It's better to use open drain drivers (and pull-up or pull-down resistors on the inputs) or at least add resistors to the driven lines so that push-pull outputs are not shorted together if multiple keys are pressed at once.
Comment: or you could use a 74c922 which basically does the same thing in a single chip https://www.fairchildsemi.com/datasheets/MM/MM74C922.pdf
Comment: @JImDearden That looks like exactly the thing I'm looking for


Do Black Arrow Multistrikes Proc Lock & Load?

Question: I know that Multistrike is the highest priority stat when playing as a Survival hunter. However what I want to know is whether or not multistrikes from Black Arrow can trigger Lock and Load for your explosive shot.
Answer: No it does not.
I am unable to find the blue source for this but once upon a time it did.
In Beta LnL was procced by Multistrike but in Blizzards Eyes it made the Spec to reliant on it so they changed it back again.


When is Gaussian mixture model more effective than Single Gaussian?

Question: From my experiment, given training samples of around 600 each having vector length of 30, the single gaussian component performed much better unexpectedly. Having said that, I want to know how or when it is better to use mixture of Gaussian (any rule of thumb or whatever)
Answer: In your case a single kernel model has $D+D(D-1)/2 = 465$ degrees of freedom, $30$ from the mean, and $435$ from the elements of the covariance matrix.  Thus you only have less than 2 samples per degree of freedom, and a two kernel model would have less than one data sample per degree of freedom.  A rule of thumb would be to require at least 3-5, and prefer $>10$, samples per degree of freedom for model estimation.
Your specific case is probably one of overfitting: the mixture model has more degrees of freedom, and thus can better fit the training data, including statistical fluctuations in it.  Sometimes this is referred to as "fitting the noise" or just "overfitting".  The lower number of degrees of freedom in the single kernel model
provided better generalization.
More generally, this is problem in model selection.
Globally, it's better to use a mixture of Gaussians when that kind of distribution can more accurately reflect the true distribution of your data.  Of course, you don't actually know the true distribution of the data.
In some cases you can identify whether a single kernel, or a mixture of kernels are required by qualitative data analysis.  Usually features like the Bayesian Information Criterion (BIC) or Akaike Information Criterion are used to formalize the idea of balancing the goodness of fit to your limited data sample against the degrees of freedom that your model provides.
Comment: Alas, AIC, BIC or DIC are not very reliable when used on mixtures, because there is not clear definition of the effective number of parameters....
Comment: @Xi'an Do you have a reference on the problems of using  with BIC (in particular) or the others?  I'm unaware of any problems with how to define the no. of parameters for a Gaussian mixture model.


Problems after upgrading to 16.04LTS: GUI not Properly working

Question: I've just upgraded to 16.04LTS. During installation everything froze. After an hour "frozen" I restarted the Laptop. I would get caught in an endless loop of turning on and off the screen. I went into recovery mode, connected manually to WiFi, ran the dpkg repair command, apt update and Upgrade -f. After that I was able to properly boot. After logging into my Account, though, only the background changes and except for the mouse pointer and desktop background (it's the correct background and even correctly changing) I have no GUI.
Service lightdm restart only brings me back to the login-screen.
Any suggestions?
Answer: apt-get dist-upgrade --fix-broken
Did the trick for me.


Is it possible to make the font size static for the Google Ad sence in all the pages?

Question: Is it possible to make the font size static for the Google Ad sence in all the pages?
Answer: You would have to configure that in the Google Adsense Ad Setup page, as it is the only way you can configure a Google Adsense Ad without breaking the terms of service.
In short, you just need to create a palette and use it on all ads you create.


Evaporation of water at room temperature

Question: Could anybody refer me to some literature (textbooks or research, although preferably textbooks!) dedicated to explaining quantitatively the phenomenon of evaporation of fluids? I understand that it's related to the temperature of the fluid (and thus the kinetic energy that some molecules may have at the surface), as well as the intermolecular forces involved; I would just like to get a more detailed look at this whole subject (more specifically, I'd like to get into the evaporation of water at different temperatures, surrounded by air at room temperature). Any help on the matter would be highly appreciated.
Answer: What makes water boil/evaporate is the thermodynamic concept derived from the first and second law of thermodynamics.
You can read this article to find out the derivation from entropy to the Clapyeron equation.
http://en.wikipedia.org/wiki/Clausius%E2%80%93Clapeyron_relation#Derivation_from_state_postulate
$$\frac{\mathrm{d} P}{\mathrm{d} T} = \frac {\Delta{H_{vap}}}{T \Delta v}.$$
And the integral form is:
$$\ln P = -\frac{\Delta{H_{vap}}}{R}\left(\frac{1}{T}\right)+C.$$
where $P$ is the vapor pressure at that particular temperature.
http://en.wikipedia.org/wiki/Vapor_pressure
For example, at room temperature (20C), the vapor pressure of water is about 2.3kPa. This means that water will evaporate until it reaches a partial pressure of 2.3kPa and then the water will attain 100% relative humidity (which means no more water can evaporate).
The driving force of this evaporation is thermodynamic related. Evaporation occurs in order for the system to reach thermodynamic equilibrium.
Below is a phase diagram - the water-water vapor phase boundary is simply the plot of vapor pressure against temperature.
Comment: "too scale"? This from WP? Probably should fix...but the "scale drawing" is also fairly useless w/o a scale.


Nvidia Series 10XX on Mac OS

Question: Does anybody use any Nvidia card (1050, 1060, 1070, 1080)on a MacPro 5,1 or else version of Mac?
I did not find any benchmark on Nvidia cards on Mac, the "sheet" of Blender developpers using cards, shows very different results according to the platform and the OS used.
Is it worth having two cards (like 2x1060-6GO)?
I've heard Blender will not add or manage 2x6GO like it would manage 12GO on a single card?
Thanks for answers
Comment: When using multiple cards, vRAM is not added to a common pool: each GPU card works with its own memory. If you use multiple cards with different amounts of vRAM, then the amount of memory available for rendering will be limited to the card that has the least. Even in cards that have multiple GPUs built in, the memory available for each one is not shared.
Comment: What's your hardware situation? Do you own a Mac already or are you looking to buy one? If you don't have one yet you might consider the recently updated Mac Pro with an external GPU connected by Thunderbolt 2 (or 3 with an adapter). You can do this with a [Bizon Box](https://bizon-tech.com).
Comment: I've one macPro late 2006 32GO
Comment: But my videocard died...So I decided to buy a Westmere 2010
Comment: Mac Pro 5,1
Quad-Core Intel Xeon
2,8 GHz
Cache de niveau 2 (par cœur) : 256 Ko
Cache de niveau 3 : 8 Mo
Mémoire : 32 Go
Vitesse d'interconnexion du processeur : 4,8 GT/s
Comment: What I'd like to do is to take the ATI Radeon HD 5770 from my new MacPro and install it in the old MacPro 1,1.
Comment: In the future I'd like to upgrade with 2x3,46 Ghz 12 cores, 32GO more ram and SSD card
Comment: Thank you for your answers, I did not know it was possible to connect an external GPU with thunderbolt. I'm gonna study this interesting way.
Answer: The GTX 10XX cards were not supported under OS X until just this past week. So benchmark data will be hard to find. For now.
Also, if you haven't already, study up on using newer Nvidia cards in the classic "cheesegrater" Mac Pro's, there are some caveats, especially if the card has not be reflashed. (off the shelf PC cards will work, but you won't have a startup splash and you may need to switch the monitor to a Mac card or use SSH to update the driver after installing OS updates)
Cycles can render across multiple cards, however the scene must copied in its entirety to each card, so you don't get to "add" the VRAM amounts. See: Does Blender support dual-GPU rendering if the two GPUs aren't the same?
Comment: My idea was to put 2x1070 or 1060. But I don't really understand how Blender manages cycle with 2x6GO (especially for volumetric, dynamics, particles...). So if each card has the entire scene, how do they share the render or bake? I think I make a misunderstanding between the CUDA for the calcul and the Vram what for?
Comment: @tontonlolo Each card works independently on a separate region of the render. Because Cycles is a global illumination render, each card needs the entire scene even though each is only working on a different portion of it.
Answer: I know I'm a bit late to the party, but thought I'd post some GTX1060 6GB results:

Render time is about 63 seconds.
That's the blenchmark scene rendered by hitting F12 (blenchmark addon throws errors when I hit the benchmark button)
Might also be worth noting that I'm running High Sierra, and on a Hackintosh.
Lastly, CPU+GPU rendering also works, causing render time to cut in exactly half.

Nvidia Series 10XX on Mac OS


What is the purpose of a JMS session?

Question: What is the purpose of a JMS session?  Why isn't a connection alone sufficient to exchange JMS messages between senders and receivers?
Answer: I had the same question and that's what lead me here. Quoting the Doc is not very helpful in this case, as I'm sure OP's question is not about how to use sessions, or what do they do, but why do they really exist, why not combine their capability with Connection. IMHO, this is a meta question.
Loosely speaking Sessions are essentially a thread's view into a Connection, Here is what the JMS spec has to say about the relation between a thread and a Session while accessing the later.

There are no restrictions on the number of threads that can use a session or any objects it creates. The restriction is that the resources of a session should not be used concurrently by multiple threads. It is up to the user to ensure that this concurrency restriction is met. The simplest way to do this is to use one thread. In the case of asynchronous delivery, use one thread for setup in stopped mode and then start asynchronous delivery. In more complex cases the user must provide explicit synchronization.

From the messaging point of view, they hold a logical unit of work. That's why the Transactions got coupled with the Sessions as well.
Having said that, quite often there will be 1:1 mapping between a connection and a Session. That's why I think JMSContext got introduced in 2.0. to simplify things.
Looking at the date of OP's post I think I am almost a decade late. :D
Comment: Just over seven years late, but better late than never. :)
Comment: What are the "resources of a session"?
Comment: To put thing simply its members, e.g. the ActiveMQSession has lots of members that cannot be accessed concurrently.
Answer: See java.sun.com
A Session object is a single-threaded context for producing and consuming messages. Although it may allocate provider resources outside the Java virtual machine (JVM), it is considered a lightweight JMS object.
A session serves several purposes:

It is a factory for its message producers and consumers.
It supplies provider-optimized message factories.
It supports a single series of transactions that combine work spanning its producers and consumers into atomic units.
It defines a serial order for the messages it consumes and the messages it produces.
It retains messages it consumes until they have been acknowledged.
It serializes execution of message listeners registered with its message consumers.

A session can create and service multiple message producers and consumers.
One typical use is to have a thread block on a synchronous MessageConsumer until a message arrives. The thread may then use one or more of the Session's MessageProducers.
Comment: Really? Copy paste from the Java API... http://docs.oracle.com/javaee/7/api/javax/jms/Session.html
Comment: The threading is a key point.  Session on down (producers, consumers, messages) are not thread-safe.  For this stuff, you must either protect from concurrent access or create multiple so multiple threads don't share.
Comment: In "single-threaded context", what is context, It is used in Spring framework, apache camel etc. Context is generally used to resolve confusion. Like wanting an apple in context of fruit or gadget.

What is the purpose of a JMS session?


How can I track UI events on Instruments

Question: I am developing an iPhone app, and I would like to see the events that are fired inside of it, for example when a tap on the screen was made, I would like to see the event fired inside instruments and learn how the objects are communicating with each other.
I tried to use Instruments to catch events using the cocoa events and it yielded nothing. The process was my app. I am not sure which profiling tool can show me what I need.
Any ideas ?
Answer: If you want to tap into the event system, you can create a custom subclass of UIWindow and override the sendEvent: method. Then you can use the Xcode debugger to examine the event object. I've used this in the past to log things like touch events.
It's not possible to do this kind of thing using the Instruments tool.


Security Management

Question: I have/am selected/considering PeerGuardian as my open-source system management application and I am trying to look into SECURITY MANAGEMENT ASPECTS of PeerGuardian. I'm looking into the research areas of reliability & relevant sources of information. Could someone help me out here as this will help in the decision making of securing my hosting services. Any recommendations ?
Comment: isn't it better to look directly at netfilter/iptables firewall rather than something that was used to protect p2p users against sting operations?
Comment: what are you trying to achieve?
Comment: I am setting up data hosting for web services and I want to ensure the services are secure so I doing a comparison of an open-source management application (PeerGuardian) against commercial products, but  I have yet to found anything(security aspects) on PeerGuardian, do you have any recommendations ?
Comment: so you're looking for a firewall application? if so for what operating system?
Comment: Erm, I am looking rather into the pros & cons, the efficiency of the PeerGuardian in particular. OS will be Linux.
Answer: PeerGuardian (by default) is for "protecting" p2p users against RIAA/MPAA/etc sting operations, so I am not sure how it will help you in your "system management" needs.
You could use it for loading up generic blacklists of IPs, though there are better apps out there for doing that sort of thing.

Security Management


Why can't the local teamcity build agent access the server

Question: I'm having trouble with the local build agent on teamcity - it can't register with the server. Remote agents are registering successfully. Here's the agent log, the server logs say nothing about it.
[2013-09-23 12:20:43,739]   INFO - buildServer.AGENT.registration - Registering on server http://localhost, AgentDetails{Name='name', AgentId=null, BuildId=null, AgentOwnAddress='null', AlternativeAddresses=[192.168.56.1, 10.55.72.133], Port=9090, Version='27540', PluginsVersion='27540-md5-2b35d17be053845ad7c8e61930f772f0', AvailableRunners=[Ant, dotnet-tools-dupfinder, dotnet-tools-inspectcode, Duplicator, FxCop, gradle-runner, Inspection, Ipr, jb.nuget.installer, jb.nuget.pack, jb.nuget.publish, jetbrains.dotNetGenericRunner, jetbrains.mspec, jetbrains_powershell, JPS, Maven2, MSBuild, MSTest, NAnt, NUnit, rake-runner, simpleRunner, sln2003, VS.Solution], AvailableVcs=[perforce, mercurial, jetbrains.git, tfs, svn, cvs], AuthorizationToken=''}
[2013-09-23 12:20:47,796]   WARN - buildServer.AGENT.registration - Call http://localhost/RPC2 buildServer.registerAgent3: java.net.SocketException: Connection reset
[2013-09-23 12:20:47,797]   WARN - buildServer.AGENT.registration - Connection to TeamCity server is probably lost. Will be trying to restore it. Take a look at logs/teamcity-agent.log for details (unless you're using custom logging).

There are no relevant entries in the Event Viewer logs.
The teamcity agent is using the same version of Java as the server.
Comment: Try to looks at the Agent log, not Server log.
Comment: @AlexanderDoroshenko This is the agent log.
Answer: Could be something with your host file if its trying to use localhost.
Try adjusting the Local Agent to connect to the same IP / Port that the remote agents are using and to set the Local Agent's IP to be that of the Machine.


Interrupt Handlers in Operating System

Question: What is the reason behind writing at least a part of interrupt handlers in assembly language?
Answer: The interrupt handler always start executing in a very low level envrionment. Programming languages but assembly always needs system libraries and something called "runtime".
For example, it is not easy to manipulate the stack pointer register outside assembly languages.
In addition, the ABI also a barrier. The Application Binary Interface is too complex in the interrupt handling, especially for the context saving and restoring.
Answer: Usually you have to write at least some part of an interrupt routine in assembly.  That's because in a lot of cases, an interrupt simply causes the processor to vector to some specific memory location and start executing code from that point.
Since your processor probably doesn't obey the calling convention of whatever higher-level lanugage you're using, you need to write some assembly code to fix that up, call some higher-level interrupt handling code, and then some more assembly code to clear the interrupt and return the system to normal execution.  On an Intel chip, for example, you need to make the processor execute an iret instruction to return from the interrupt.  There's no way to do that in any standard way in any high-level language.

Interrupt Handlers in Operating System


Saying |ameen" when is it appropriate to respond with the word "Ameen"

Question: I see many people responding with this word on social networks for a simple postings such as Hadith, or a parable, or just a greeting for Eid or Ramadan etc,
should it be pronounced on a network, as it is not a live gathering.
eg:  I posted "Ramadan Kareem on Facebook, and 20 responses appeared in the comments!
I am confused, because this is not a Duaa in live gathering!
Comment: Salam and welcome to Islam SE the Q&A site about Islam. Please consider taking your time to take our [tour], check our [help] and [meta] to learn more about this site.
Answer: Ameen or aameen آمِين means اللهم استجب May Allah accept or answer (our dua' اللهم استجب دعاءنا).
Saying/posting ameen is only allowed in two situations according to this Article of Sheikh Shanqeety which comments this hadith of Jami' at-Tirmidhi and includes fatwas on the purpose of that hadith:

in the prayer for example: when finishing the recitation of al-fatiha.
and as a kind of response or reaction if one hears/reads an allowed dua', so once you hear/read somebody making dua' you are allowed (asked) to say ameen, but not for any dua' as an example: If somebody is making dua' asking Allah to cause pain to a Muslim or asking Allah for something which is not allowed, one shouldn't say ameen.

These are the only two reasons or situations saying ameen is allowed or legislated.
So if anybody posted ameen in such a situation as described in your post you should explain to him, that this isn't allowed or at least unlawful and he/she should rather use thanks/JazakaALlah khayran etc. instead of ameen.
And Allah knows best!


SFDX Force Redeploy

Question: Is there a way to force SFDX to deploy all assets again even if they've already been deployed? I thought -f overwrite might do it but it doesn't seem to override what it thinks is already deployed. It also doesn't appear to be smart enough to know that we're trying to deploy to a different org
Answer: I used sfdx force:source:deploy instead of sfdx force:source:push which worked. I don't know if it'll mess up the tracking but I'm hoping not.
Comment: Some time ago I was removing orgs folder inside .sfdx in project root to achieve same scenario, especially when deployment was partially done, and there were no help from -f option

SFDX Force Redeploy


Can't push to git via Android studio?

Question: I cloned a Repository from Github via Android Studio. I made some changes to the code, then committed & pushed without a problem. Today, I made some changes to the code. I committed them but when I tried to push them it says

Can't push, because no remotes are defined

Thanks for your help..
Comment: I have the same issue. The remote has clearly been set up and I can push with Git extensions without any problem, but I see this screen in Android studio.
Answer: Apparently there's no way to do it from the IDE, some bug must have deleted your remote.  If you open up the config file in your .git directory within your project folder, goto the bottom and insert:
[remote "origin"]
url = https://github.com/YOURPROFILE/YOURREPO.git

Answer: Maybe, it is late to answer, but I got related problem yesterday in IDEA.
I have separate repository for each module and when I initially checkout them into local repository all remotes were called origin. Yesterday I changed remotes for some modules but not by replacing - by adding new_remote and removing origin. So I got smth like that:
module_1 -> {new_remote/master}
module_2 -> {origin/master}
module_3 -> {origin/master}
...
module_n -> {new_remote/master}

From that moment I received error Can't push, because no remotes are defined every time I tried to push. In git bash all worked fine, but not in IDEA. I spent whole day and at evening I tried last solution and it worked - I changed all local repositories to have identically named remotes. In my case, I renamed origin for modules to new_remote.
As I understant you can have smth like this:
module_1 -> {origin->[master, test], staging->[master]}
module_2 -> {origin->[master], staging->[master]}
module_3 -> {origin->[master, test]}

But from Intellij native plugins in this case you will be able to push only to {origin->[master]}, because only this remote/branch pair is common to all registered in this project repositories.
ALso, it seems that this limitation wil  be fixed in later versions. - https://youtrack.jetbrains.com/issue/IDEA-81620

Can't push to git via Android studio?


How to force mathematica to take derivatives in a specific way?

Question: I am attempting to take some derivatives of some Lagrange planetary equations. In this I have two types of anomaly which have derivatives that are found geometrically. I'm trying to force mathematica to use the results of these derivatives. I realize that to do this I have defined the derivatives. To get Mathematica to be happy I unprotect D before doing so. Heres my code for that:
Unprotect[D];

D[f, e] := (a/r + (\[Mu]*a)/((\[Mu]*a)^(1/2)*(1 - e^2)^(1/2))^2)*Sin[f]

Unprotect[D];

D[f, M] := (1 + e*Cos[f])^2/(1 - e^2)^(3/2)

Okay so this is all well.  When I evaluate D[f,M] or D[f,e] it seems to work correctly; however when I take the derivatives of other functions derivatives don't follow those rules I set above. For example, I made up a simple function to check this:
In[58]:= abc [a, e, i, f, c] := e*f*Sin[f]

In[59]:= D[abc[a, e, i, f, c], e]

Out[59]= f Sin[f]

Uh oh. So my question is how do I get mathematica to match the derivatives I want?
Thanks for all your help
Comment: Why unprotect `D`?  What happens if you simply use the standard derivative?
Comment: `D[f_,e]:=` ,  `D[f_,M]:=`
Comment: ah wuyudi that worked perfectly!!!
Answer: From Wuyudi, the answer is:
D[f_, e] := ...
D[f_, M] := ...


Why did Luffy react to Nami's body, but not to Hancock's?

Question:
When Luffy saw Nami's naked body thanks to Mr. 2 and later in chapter 213 due to her happiness punch, he reacted and got excited. But on the other hand, when Luffy saw Boa Hancock naked it did not affect him in any way. Why was Luffy affected by Nami's body, but not by Hancock's body?
Answer: A different reader had the same question and according to Oda, it was all because of Usopp's bad influence. Luffy and Usopp are of the same age, so  when they are together it would be like kids going on a school trip: their bad side comes out!
From SBS of Volume 54, chapter 523:

Reader: Hey, Oda. In volume 53, chapter 518, Hancock's "Mero Mero Mellow" had no effect on Luffy at all, but in volume 23, chapter 213, it looked like he had a reaction to Nami's "Happiness Punch". Why did he respond to Nami's naked body but no to Hancock's? Is Nami's body just that amazing? -Kazu
Oda: Wow, I got a lot of questions about this. Is this what you guys are paying attention to? Don't just read manga all day, go study some more!! Okay? Well, I say that, but I do nothing but draw manga. I noticed this when we were drawing it, but if Luffy had a nosebleed when he saw Hancock's body, I think you would all be like "Ehh!?". That's not the Luffy we know. I believe that Luffy reacted to Nami's naked body twice, in volumes 18 and 23, and both times it happened, Usopp was with him! He's the suspicious one! In other words, when Luffy is alone, his reaction is what it was with Hancock. He's interested, but he's not entranced by her. But when he's with Usopp, who's the same age, it's like a kid on a school trip: his bad side comes out!! Yeah, both sides of Luffy feel right to me, so the culprit is definitely Usopp!!
Comment: Yea your answer seems right i guess since it was straight from Oda himself
Answer: I think it's because Oda is a fan of Nami himself and somewhere else made mention that Nami is his favorite. (Hell he even Married a Nami from one of the live action Shows in Japan). So I think since Luffy is the main character he reacts to his own Nakama/Friends naked as more of a shock. Where as we know Sanji will just gawk at about any woman, even if they were wearing 90 layers of Parkas and had only one EYE visable LOL.
Boa is the one obsessed with Luffy, and Luffy can't be bothered by her. It'd be much like having a stalker, who is so entranced with you that if they stripped naked in front of you to get your attention, you still would "NOT care". Also with my theory why Nami affected him, think of if you saw your own friend of the opposite gender naked, you'd probably react with shock too. I know I would.
Answer: Notice how in the image provided, Luffy and Usopp have the exact same expression on their faces. I'd say it a combination of

Amazement at #2s power,
Shock at seeing his friend in such a way, and
He's just straight up mimicking Usopp in an attempt at a "proper reaction" to the situation.

After all, Luffy tends to be almost sociopathic in reaction when it comes to these kinds of situations. Fighting, food, treasure, and related topics he is all excited over, but girls he is oblivious to...
Answer: The reason it is like that is because Boa took it off to show the celestial dragon mark and just tried to kill Luffy, and it would be disrespectful to stare at Boa like that.
On the other hand, Luffy might actually just be impressed with Mr. 2's abilities, and Luffy has been friends with Nami for months and knows her personality.