I have a PlayStation 4 controller and I paired it to my Chromebook but now it won't connect to my PlayStation 4. I have reset it but it still doesn't work.  What should I do?
I was playing my PS4 two days ago and then packed it up with two controllers that were both connected to this PS4.   I got to where I was going, set everything up and now the controllers won't connect. They show pulsing orange when they plug in, but when I hit the PS Button to connect, it blinks white 1-2 times and goes back to orange.   I have tried resetting them both.  Can anyone help?
Local timezones on servers considered harmful? I'm curious as to what other administrators' experiences with timezones, in the context of remotely administered servers, are. In my career I've come across several conventions;   Always, always, always use UTC.   Always, always, always use the timezone of wherever base HQ is. Use the local time of the people who happen to be administering.  Use the local time of the server location.    In some places, I've come across multiple and conflicting conventions. My own preference has been to use UTC, always - with no daylight savings. But for one reason or another, it seems that most people prefer to use some concept of local time, with daylight savings. Although it seems like a straightforward technical matter, discussions around changing conventions always seem to trend towards religious schisms.  What are you using? What do you consider to be the advantages and disadvantages of each approach? Algorithm to return all combinations of k elements from n I want to write a function that takes an array of letters as an argument and a number of those letters to select.   Say you provide an array of 8 letters and want to select 3 letters from that. Then you should get:  8! / ((8 - 3)! * 3!) = 56   Arrays (or words) in return consisting of 3 letters each. Is there any easy LINQ expression to concatenate my entire List&lt;string&gt; collection items to a single string with a delimiter character?  What if the collection is of custom objects instead of string? Imagine I need to concatenate on object.Name. $\mathbb Z[i]/ \langle 1+2i \rangle \cong \mathbb Z_5$ I am trying to prove that $\mathbb Z[i]/ \langle 1+2i \rangle$ is isomorphic to  $\mathbb  Z_5$.   The only thing that came to my mind was trying to apply the first isomorphism theorem using an appropiate function. If I consider the euclidean function $N: Z[i] \setminus \{0 \}  \to  \mathbb N$ defined as $N(a+bi)=a^2+b^2$, then I can express any element $z$ in $\mathbb Z[i]$ as $z=(1+2i)q+r$ with $N(r)=1,2,3,4$ or $r=0$.   If I define $f:\mathbb Z[i] \to \mathbb  Z_5$ as $f(x=(1+2i)q_x+r_x)=\overline{r_x}$, then it is clear that $f(x)=0$ if and only if $x \in  \langle 1+2i \rangle$. The problem with this function is that it doesn't satisfy $f(x+y)=f(x)+f(y)$ and it is not surjective for if $r_x=f(x)=3 (5)$, then if $r_x=a+bi$, we have $a^2+b^2=3$, which is absurd.  I don't know what else to do, any suggestions would be appreciated. Given a Java InputStream, how can I determine the current offset in the stream? Take a look on a website with specified viewport size, that is bigger than physical size? How does Azkaban's management work? I was under the impression that only Dementors are guarding the prison of Azkaban and are only there to keep the inmates on their cells, though after reading again the following passage it put me into thoughts:     'One night, when (the Dementors) opened my door to bring food, I   slipped past them as a dog. It's so much harder for them to sense   animal emotions that they were confused ... I was thin enough to slip   through the bars. I swam as a dog back to the mainland. I journeyed   north and slipped into the Hogwarts grounds as a dog. I've been living   in the Forest ever since.'       Prisoner of Azkaban; chapter 'The Servant of Lord Voldemort'   So Sirius says that he escaped from his cell when the Dementors brought him food.... I say what??? Dementors dont obey anyone, not even the commands of the Ministry of Magic.  So the actual question is, How is the Azkaban prison managed? e.g. who cooks the food? the inmates have blankets, who is washing these blankets etc etc Random Forest mtry Spit-to-Split Variable Sampling Procedure I would like to clarify something that I don't think is clear in   The first automatic delete rule kicks in at 9 days for closed questions:     If the question was closed more than 9 days ago, and ...         was not closed as a duplicate   has a score of 0 or less   has no answers with a score > 0   some other criteria that don't matter right now...      Then, at 30 days, there's:     If the question is more than 30 days old, and ...         has −1 or lower score   has no answers   is not locked      This rule applies to both open and closed questions, but it doesn't mention the same exemption for duplicates.  I'm pretty sure that I've seen old, downvoted duplicates disappear on ServerFault (and that fits what the rule says), but I'm also sure I've seen lots of comments along the lines of  "duplicates aren't deleted."  So what I'm after is a clear statement from a power-that-be or a clear reference that says "duplicate questions fall under the same 30-day automatic deletion rule as any other question."  (or that they don't)  (Note: I realize this doesn't apply the stub left behind when a question is merged into another.  Those "stubs" are locked and are never deleted.) How to make a div 100% height of the browser window I work sometimes till 4 am and my friends and the rest of the world obviously don't know in advance that I don't want to be called at 8 am.  Is there an app or setting that can allow me to have an emergency override list of people I need to be woken up for if a possible emergency arises but ignore all other calls until I wake up?    I'm familiar with the Do Not Disturb option, but it has limitations that it blocks all calls. What if there is an emergency at night?  What if I want to allow certain callers during the Do not Disturb time? Is there a way to have an emergency list that allows calls during silent? Is there a convergent, alternating series that fails the AST? The alternating series test (AST) says, briefly, that if   $a_k&gt;0$ $a_k \geq a_{k+1}$, and $a_k \to 0$ as $k \to \infty$   then $\sum_k (-1)^k a_k$ converges.  This seems to be a one-way test (that is, if an alternating series fails the test, we don't know that it diverges).   document says so explicitly. It then gives an example of an alternating series which fails the AST. That doesn't prove the series is divergent (but it turns out to be divergent, anyway, by $n$th term test).  Is there a convergent, alternating series that fails the AST?  Of course, if the series fails condition 3, then it also fails the $n$th term test, and must diverge. And if it fails the first condition, then it's not strictly alternating, anyway.  So it must be a series that is not getting smaller (condition 2), but still converges. Is it possible to set an SSLProtocol in Apache for a single VirtualHost (poodle)? I'm trying to test a patch for the  that involves disabling SSLv3 on my web server. In order to test this on a non-production environment first, I'm setting the SSLProtocol on a VirtualHost for a different test server. My config looks something like this:  &lt;VirtualHost *:443&gt;     SSLEngine On     SSLProtocol All -SSLv2 -SSLv3     ServerName test.mysite.com     # bunch of other stuff omitted &lt;/VirtualHost&gt;   However even after restarting apache my test site is still claimed to be vulnerable. Is this expected to work? I'm wondering if I have to set it in the global ssl config or whether there's something else subtle that's causing the setting not to take and/or work. Marking plural of code words In my blog (which is about programming) I often use reserved words from different programming languages.  Like this:     When column is nullable in both tables, this query won't return a match of two NULLs for the reasons described above: no NULLs are equal.   Here, NULL is a programming language keyword.  For numerous reasons, I mark them with &lt;code&gt; tag so they are rendered with a fixed width font, not translated into the foreign languages by Google Translate, can easily be seen on the page etc.  In the example above, which would be the best way to mark the plural?   NULLs NULL s NULL's NULLs NULLS   Option 1 looks ugly on the page (the word and the plural marker are rendered in different colors and fonts)  Option 2 adds a space between the word and the plural marker  Option 3 looks nicest but is not correct  Options 4 and 5 may leave the reader under impression that NULLS is a reserved word (which is not true) and this may be confusing. Also, Google Translate would leave the word as is which would be definitely wrong in other languages.  What would be the least of 5 evils? A PC in our group was off on his own following a recurring villain of our groups. He was paralyzed where he could move, and the vampire bit his neck. The vampire said "now you get to remain 19 (years old) forever" before he left the cave. This was all done in RP.  We found him later, and healed up his bite marks. Our characters know of vampires, specifically only the one that bit him (recurring villain), but don't really know how vampirism works, because it isn't a super common thing in this world yet.   My question as the player is:  How does RAW vampirism work in 5e?  Is it a disease that develops over time? Is it something where they have to die and be brought back as a vampire? "The following packages have been kept back:" Why and how do I solve it? I just added a PPA repository for the development version of the GIMP, but I get this error:  $ apt-get update &amp;&amp; apt-get upgrade ... The following packages have been kept back:   gimp gimp-data libgegl-0.0-0 libgimp2.0   Why and how can I solve it so that I can use the latest version instead of the one I have now? Cylindrical vs azimuthal symmetry I can't crack this one.      Prove: If $\gcd(a,b,c)=1$ then there exists $z$ such that $\gcd(az+b,c) = 1$ (the only constraint is that  $a,b,c,z \in \mathbb{Z}$ and $c\neq 0)$ Shell command for outputting absolute path of binary Is there a shell command for outputing absolute path for specified program? I'd like to know where executable binary file is. Force JSF to process, validate and update readonly/disabled input components anyway