Visiting the UK as a tourist and later returning to UK

I'm from Argentina wanting to joining my girlfriend who will be studying for one year in Edinburgh. As an Argentine I don't need any particular permit to go to UK as a tourist. The permit of stay is for a maximum of 6 months.    But what if after the 6 months I go to e.g. Spain for one month and then return to the UK - does the tourist 6 month permit start running again?   Is there a minimum period of time for which you have to be out of the UK so as the tourist permit starts running again?  I'm only considering the option of leaving to somewhere in Europe.


Why has the speed of light in a gravitational field always the same value $c$ when measured locally?   More precise: When you are far away from any masses, that means when the spacetime is flat, and you measure the speed of a light ray that passes you, you will always get the same value $c$. Now suppose you are in a static gravitational field at a fixed position, and do the same. Why do you also measure the same value $c$? (Please note: You are not in a free falling system where gravity vanishes)


How use a preset WINE prefix during the installation on POL?

I'm trying to run a game which need to be run under a 32-bit prefix (due to component needed).  I succeeded in creating the folder; the problem is as I'm setting up the program POL installed it as default in a automatically-generated wine prefix (64-bit due to my config).  How can I install my game in a pre-existing prefix? Or Maybe did I miss a step and you can choose it during the installation but I did not find it?  I can choose either the 32 or 64 before the installation using POL but then when I try to add components to it I get something like unable to set it in a 64-bit virtual drive.


Clear input value on dynamically add/remove inputs

I have input element that can clear value when click the button.  Also this input can be dynamically adding or remove input element.  But I am stuck with when after add input element, the clear button is not working.   This is what I tried so far here     // ADD , Remove input var counter = 1,   custom = $('#custom'); $(function() {   $('#add_field').click(function() {     counter += 1;     var newRow = $('
<input id="exception_' + counter + '" name="" type="text"><button class="btn_clear">clear</button><button class="remove-text-box">Remove</button>
');     custom.append(newRow);     (function(index) {       newRow.find('.remove-text-box').click(function() {         custom.find('.row' + index).remove();       });     })(counter);   }); });   // clear input value  $('.wrap_input').each(function() {  var $inp = $(this).find("input"),       $cle = $(this).find(".btn_clear");  $inp.on("input", function(){    $cle.toggle(!!this.value);   });  $cle.on("touchstart click", function(e) {    e.preventDefault();     $inp.val("").trigger("input").focus();     $inp.change();   }); }); .btn_clear { display: none; }  <button id="add_field" href="#">add input</button>
           <input type="text" value="">     <button class="btn_clear">clear</button>
     The first input is working well, but after adding input element clear button is not appeared.   Please help.


Why is my USB drive showing corrupted data when plugged as an internal SATA drive?

I have a 3TB Seagate Backup Plus Desktop USB 3.0 drive, which works fine when in its enclosure, but when I get it off its enclosure and directly plug it as an internal SATA drive, it's just not properly recognized (it works again when used in the enclosure). My systems’s motherboard is an , which has two SATA 6.0 Gb/s and four SATA 3.0 Gb/s ports.  When used as an internal SATA drive Windows 7 asks if I want to format the drive, as if it didn’t have a proper filesystem, and if I use the DISKMGMT.MSC tool (typing that in the start menu) I get completely wrong information about the drive.  It says the drive has 3 partitions (349,31GB of RAW data and two unassigned partitions of 1698,68GB and 746,52GB). This information is plain wrong, since the drive, when used in the USB enclosure, works as a single NTFS partition (2794,52GB). How come it’s shown as 3 partitions without filesystem when connected through SATA?!  Is Seagate using some proprietary way of storing the data when using the drive in its provided USB 3.0 enclosure? I didn’t use any kind of encryption. I just plugged the drive with USB 3.0 and started using it straight away, since it apparently came pre-formatted with an NTFS filesystem.


One central observation is that the vast majority of Robo-Advisors base their investment approach on ETFs. About 70% of the examined providers even operate on an “ETF-only” approach, to maximize cost-efficiency for highly diversified yet small portfolios. ()  To me this seems like a really good deal for the company offering the robo advisor and a really bad deal for the customer. After all, choosing a handful of index based funds in various geographic regions is not a complicated operation and will reflect the overall market performance quite well while maintaining a good diversity. Is there any good reason to pay a fee of typically 0.5-1% for a robo advisor?


What is the scientific reason for the inclination of earth's rotation axis?

This titled position of the earths axis is known as inclination of the earths axis. The earth's rotation axis makes an angle of about 66.5 degrees with the plane of its orbit around the sun, or about 23.5 degrees from the perpendicular to the ecliptic plane  what is the scientific reason for the inclination of earth's rotation axis?   and what will happen if the inclination angel changed?


Series rearrangement and Riemann's theorem

I think understand that when I have a conditionally convergent series, it consists of series of positive and negative values which are divergent and thus one can find such permutation of indices $\phi : \mathbb{N}\rightarrow\mathbb{N}$ so the rearranged series sums up to an arbitrary value, diverges or oscillates.   This is how I understand what Riemann's rearrangement theorem says, but how do I use it practically? For example, when I have the conditionally convergent series:  $$\sum_{n=1}^{\infty}\frac{(-1)^n}{\sqrt{n}}$$  and I want to rearrange it to be divergent or to sum up to certain value M? How do I define such bijections $\phi$ ?  I appreciate all help.


Every prime divisor ($p \neq 5$) of $n^2+n-1$ is of the form $10k+9$

Now, what I have done so far is the following:  Let $p$ be a prime such that $p | n^2+n-1$, then $n^2+n-1 \equiv 0 \pmod p$  This congruence has a solution if and only if $x^2 \equiv \Delta \pmod p$ has a solution, where $\Delta = b^2 - 4ac = 1^2 - 4\cdot1\cdot(-1) = 5$.  Since $\Delta = 5$, this has a solution iff $(\frac{5}{p}) = 1$ (the Legendre symbol).  And this Legendre symbol is $1$ iff $p \equiv 1, 4 \pmod 5$   Which, in turn, means $p \equiv 1, 4, 6, 9 \pmod {10}$. But $p$ cannot be congruent to $4$ or $6$ modulo $10$, for otherwise it would not be a prime.  Therefore, $p \equiv 1, 9 \pmod {10}$.  How do I get rid of the $p \equiv 1 \pmod {10}$ solution and prove that it can only be congruent to $9$, i.e. be of the form $10k + 9$, for some k?  Is this proof valid for all choices of $p\neq 5$? If so, mayhap my teacher forgot about the $p$ of the form $10k+1$?


I am looking for a list of all the strings the render special in LaTeX, for example \latex and \python, I believe are both special. Are there others? Is there a list somewhere?


Is there a way to edit or delete and reenter comments once they're posted?

I just posted a comment to someone's answer on SO and accidentally left off the very first backtick, resulting in a really messed up looking comment. Of course I couldn't see the result of that omission until I posted it and by then it was too late to fix it. Is there anything I can do to fix it?


There are plenty of situations where the use of a * is virtually inevitable - e.g. rm -rf * in a folder that holds thousands of subfolders and files.  But what if you want to exclude just one or two files or folders from the rm command? I've googled my way around and only found quite complicated solutions like find . -depth -not \( -name 'one' -o -name 'two' \ -o -name 'three' \) -exec rm {} \; as stated .  Is there a possibility to do this in an easier way - without that detour to find? E.g. rm -rf --exclude='one' --exclude='two' --exclude='three' * like in rsync or just rm -rf -e 'one','two','three' *?  Maybe even a general possibility to exclude things from * (so other commands like cp, mv, ... don't have to implement their own)? Something like *{'one','two','three'} or so?


How to print window without footer in php?

I am trying to print the window without header and footer but if i print printContents as  then css are not attached and if i print originalContents then footer are seen as   . Thanks in Advance <script>    function printTicket(printable) {       var printContents = document.getElementById(printable).innerHTML;       var originalContents = document.body.innerHTML;       document.body.innerHTML = printContents;       window.print();       document.body.innerHTML = originalContents;    } </script>  This is button of print   <button type = "button" class = "btn btn-outline-secondary btn-preview" id="printable" onclick = "printTicket('printable')">Print</button>


Can we change permissions on a symbolic link?

on a course exercice they ask me to change permissions on a symbolic link , but i try chmod but they didn't work , and after i search on internet but i didn't see a request for my questions.  Do you have suggestions ?  (Sorry for my english)


How do I block this (carrier) advertisement dialog?

I receive this kind of messages almost every day, and I'm tired of them.   Screenshot (click image for larger variant)  I want to block them, but I have no idea how are they called.  I'm looking for a way to block this messages, either via an app (doesn't matter if it needs root) or programatically (if I can detect these messages, perhaps I would be able to create an app to block them).  EDIT: The message icon is the same as the SIM Toolkit. Could this be related? As far as I know, Cell Broadcasts don't show with "OK" and "Cancel" buttons as this message.


Given two square matrix matrices ($A$ and $B$ both have the same order) such that $AB = I$ is it true that $BA=I$?

my try:  $AB = I$  $BAB = B$  $BAB = B$  $BAB - B= 0$  $(BA - I)B= 0$  I wanted to be able to multply by A and appear AB somewhere up there...  $AB = I$  $ABA = A$  $A(BA - I) = 0$  mmm.... can someone gimme a hint at least ? I know we can't say that because $B$ is not null (although this is true) then $BA-I$ must be null


What diary-style book has a family flee destruction of earth by exploding sun and try to survive on a new planet?

I’m looking for a book I remember. A girl her father and brother (?) leave earth on an ark ship headed to another planet. After several years (?) they arrive on the new planet, but it is much harder to survive than anyone thought.  I specifically remember crops not growing the way everyone thought they would and their animals dying. Wheat is crystalline and practically inedible, etc.  There were also some kind of moth people.  The kids end up helping everybody because they are more adventurous than the timid adults and try new foods etc.  They get through the first year and realize they should be recording their history in some way.  They find out the girl had been keeping a diary and begin reading it aloud. The first sentences are the first ones of the book.


How to generate n different colors for any natural number n?

Say n = 100; How do I generate 100 visually distinct colors? Is this mathematically possible?


Do continuous linear functions between Banach spaces extend?

Just wondering... Let $E$, $G$ be Banach spaces, let $U\subset E$ be a subset of $E$, and let $f:U\rightarrow G$ be a continuous linear function. Can $f$ be extended to a continuous linear function on $E$, $F:E\rightarrow G$? For which cases does this happen?


What happens to matter in a standard model with zero Higgs VEV?

Suppose you reset the parameters of the standard model so that the Higgs field average value is zero in the vacuum, what would happen to standard matter?  If the fundamental fermions go from a finite to a zero rest mass, I'm pretty sure that the electrons would fly away from nuclei at the speed of light, leaving positively charged nuclei trying to get away from each other.  Looking at the solution for the Hydrogen atom, I don't see how it would be possible to have atoms with zero rest mass electrons.  What happens to protons and neutrons?  Since only a very small part of the mass of protons and neutrons is the rest mass of the quarks, and since they're flying around in there at relativistic speeds already, and since the nuclear force is so much stronger than the electrical force with an incredible aversion to naked color, would protons and neutrons remain bound assemblages of quarks and virtual gluons?  Would they get a little larger?  A little less massive?  What would happen to nuclei?  Would they stay together?  If the protons and neutrons hold together and their properties change only some, then I might expect the same of nuclei.  Different stable isotopes, different sizes, and different masses, but I would expect there would still be nuclei.  Also the W and Z particles go to zero rest mass.  What does that do to the electroweak interactions?  Does that affect normal stable matter (outside of nuclear decay modes)?  Is the weak force no longer weak?  What happens to the forces overall?


What is the difference between the two following arrows $\mapsto$ and $\to$?

Can someone please define the meaning of the two following arrows and tell me what the difference is between them? When would you use one or the other?  $\mapsto$ and $\to$  Thank you so much!


Evaluating a limit using Squeeze Theorem.

Consider a function $f (x)$ defined on $\mathbb{R}$ satisfying:  $$ \left|f(x) - \frac{7^2 + 5x|x|+2}{x^2+16}\right| \leq \frac{1}{x^2} $$  for all $x\neq0$. Calculate: $\displaystyle \lim_{x \to \infty} f(x)$ and $\displaystyle \lim_{x \to −\infty} f(x) $.  Considerations:     If $x \to \infty$ then we can consider $|x| = x$      If $x \to -\infty$ then we can consider $|x| = -x$.


Traffic jams driving on the D1 from Praha to Brno

We will leave tomorrow morning to Brno. Are there are any road works that might cause jams? I saw that just before Brno there is a long part of workings, it's possible to Block the cars flow.  Any alternative routes?


How might I enable Quantum GIS to read ECW imagery?  At the moment I'm mostly concerned about this on Ubuntu 10.4 amd64, but I also use WinXP & Win7.


Question About A Problem About Rational Numbers

I'm a bit confused about what I am supposed to prove in this step of the problem. Am I supposed to prove that for any positive integer $T$, no matter it's size, I can always find positive integers $b<c<d<etc.....$ that are greater than $T$, and such that $a = 1/b + 1/c + 1/d...etc $?  Also, could you avoid giving me any hints on how to solve this problem, or information about rational numbers, when answering the question? I still want to try and figure out how to solve this question.   Thanks in advance.


How to create multiple rows combining data sets

I have three tables and i need an out put which has data from two tables, i would like to create the same using macro.  Table A  A B C D   Table B  Apple Orange Pears   Table C  Americas Asia Europe   The Output i need is  A Apple Americas A Apple Asia A Apple Europe A Orange Americas A Orange Asia A Orange Europe   So i guess for each letter from Table A, there would be 12 additional rows created. The above is the sample data and I have around 5000 rows in Table A.


Thread is throwing null pointer after x amount of times

Edit: It's not something as simple as a nullpointerexception being thrown. The thread is working severable times before throwing the nullpointerexception meaning that it suddenly decides to stop working and I can't figure out why  Hello I have the following thread  private class IsCreditAdded implements Runnable{     ActionEvent evt;      public IsCreditAdded(ActionEvent evt){         this.evt = evt;     }      @Override     public void run(){         while (AddMinutes.creditChosen != true){         }         creditAdded(evt, AddMinutes.getEvt());      } }   It waits for a boolean to change from a GUI class with options to select a value, and then when the boolean changes it executes a method called creditAdded with values evt(passed in from constructor), and a static getMethod which contains the ActionEvent which was selected  public void creditAdded(ActionEvent evt, ActionEvent duration){     System.out.println(evt.getActionCommand() + " " + duration.getActionCommand());     switch (evt.getActionCommand()){         case ("voipCredit"):             switch (duration.getActionCommand()){                 case ("cancel"):                     System.out.println("CANCEL");                     disableButtons(evt, duration);                     break;             }     addMinutes.dispose();     AddMinutes.reset();     sessionStorage.printTransActions(); }   Here is where the thread is created:  private void creditButtonActionPerformed(java.awt.event.ActionEvent evt) {                                                   switch (evt.getActionCommand()){         case ("voipCredit"):             addMinutes = new AddMinutes();             addMinutes.setService("VOIP");             addMinutes.setVisible(true);             addMinutes.setDefaultCloseOperation(DO_NOTHING_ON_CLOSE);             addMinutes.setPrices(nf.format(SessionPrices.getVOIP_10_MINS()), nf.format(SessionPrices.getVOIP_30_MINS()),                      nf.format(SessionPrices.getVOIP_1_HOUR()), nf.format(SessionPrices.getVOIP_ALL_DAY()));             threadVar = new Thread(new IsCreditAdded(evt));             threadVar.start();               disableAllButtons();             break;     } }   Now the problem Im having is whenever I select the button which gives the getActionCommand 'cancel' it works two times, sometimes three, but then if I try it again I get a nullpointerexception. The actual error message I get is:     Exception in thread "Thread-6" java.lang.NullPointerException        at com.aidanmoore.InternetCafeGUI.creditAdded(InternetCafeGUI.java:416)        at     com.aidanmoore.InternetCafeGUI$IsCreditAdded.run(InternetCafeGUI.java:411)        at java.lang.Thread.run(Thread.java:745)        BUILD STOPPED (total time: 9 seconds)"   I can't figure out why it is throwing this exception after hours of searching for similar problems others have had and since the thread works x amount of times before throwing the exception I Cant work out why it suddenly breaks


Securely wiping RAM with sdmem at shutdown

I've already looked at "", but that's not what I'm looking for exactly.   I'd like to have it so when I shut down my machine, it executes the "" program, securely wiping my RAM. I've looked around at some other tutorials online related to this topic, yet none of them are really definitive of what needs to be done for this to execute successfully.  The program needs to be run as root, and I'm running Debian jessie if that really matters.


Show that $\lim_{n\to\infty} \sqrt[n]{a^{n} + b^{n}} = \max(a, b)$

Prove that:  $$\lim_{n\to\infty} \sqrt[n]{a^{n} + b^{n}} = \max(a, b)$$  I don't have a clue even how to start the proof here. Any hint is appreciated!


python script that reads text file containing coordinates and creates a path/curve for object to follow

I am a highschool student working at a college's engineering department for the summer. I just began working in blender and have intermediate knowledge of python. Could anyone share a script they've made that can:  1) Read a text file of xyz coordinates into python.  2) Turn these points into some type of curve or path that an object can then follow to model the path the coordinates map out.   Like i said i don't have a great understanding of blender but if someone could write or give me a script that is able to do this it would help. Please explain in simple terms also.. Again I am not an expert.   The file has three points on each line, separated by commmas, and is pretty large. All the coordinates would need to be floats on account that they are decimals.     -4.934860e-06 , -1.380798e-06 , -1.504166e-05 ,  -1.359547e-05 , -4.301138e-06 , -4.403530e-05 ,  -3.727631e-05 , -1.307421e-05 , -1.287422e-04 ,  -7.177810e-05 , -2.724715e-05 , -2.643154e-04 ,    here are some of the data points when in the text file  now with the .csv they were put into an excel file   when copied and pasted they look like this:  -4.93E-06   -1.38E-06   -1.50E-05


This seems to be rather hit & miss, but often a link posted on SE leading to support.apple.com/kb/[reference code] seems to just give a blank page, as though it neither loads nor times out.  Sometimes a refresh will load it correctly, sometimes not.  Is there any workaround to this issue?  Edit: I've tried the Remove all website data suggestion, which worked for about 2 days, so I'm back to the manual 'cut the kb number, paste it into the main page' method.


Proving Lie algebra isomorphism to $\mathfrak{sl}(2, \mathbb{C})$

The question: Let $L$ be a three dimensional simple Lie algebra over $\mathbb{C}$. Say that $x \in L$, $x \neq 0$, and that $ad_x$ has an eigenvalue $\lambda \neq 0$. Show that $L \cong \mathfrak{sl}(2, \mathbb{C})$.  Things I've tried: We can say $[h,e] = 2e$, $[h,f] = -2f$, and $[e,f] = h$. If I say $ad_x(y) = [x,y] = \lambda y$ then maybe I can have a basis $\{x,y,z\}$. I tried to just create a map $\phi(\frac{2}{\lambda}x)=h$, $\phi(y)=e$, and $\phi(z)=f$. Then I think $x$ and $y$ work but I'm not sure how to ensure $z$ works the way I want.


I have a question, which may seem strange. I checkout some source code from SVN. However, for some reason I do not want this source code to be controlled by SVN. Are there methods to make it look like independent code without being controlled by any source control software. By the way, I am using Tortoise SVN in windows.


We flip a fair coin (independently) three times. Define the following two events:  A = "the number of tails is odd"  B = "the first coin comes up heads"  Are the events A and B independent?  I believe this is not independent.  My though process as follows with math.  The sample space for three flips is $2^3 = 8$  $S = \{ HTT,HHT,HHH,THT,TTH,HTH,TTT,THH \}$  Event A = $\{ THH,HTH,TTT,HHT \}$  Event B = $\{ HTT,HHT,HHH,HTH \}$  We need to prove $P(A \cap B) = P(A)\cdot P(B)$  $P(A\cap B) = \frac{2}{8} = \frac{1}{4}$  $P(A)\cdot P(B) = \frac{4}{8} \cdot \frac{4}{8} = \frac{1}{4}$  Since $P(A \cap B) = P(A)\cdot P(B)$ then events A and B are independent.


When is the best time to validate an Input Field in a form?

I have a form with a few fields in them. I wish to validate all of them before I could submit the details entered. For example, First Name should have atleast 1 character. Email should match the Email-format. Password should be atleast 6 characters and so on...  Based on the validation, I have to put a green-right-tick or a red-cross symbol at the end of the field.  I'm working on an android app, but I think a similar problem could occur in a web app too.  Now, my question is when should I validate the fields? By validating, I mean either I put the right-tick or, the wrong-cross with Error Message. Here are the options that I'm considering right now:   I validate them with every keystroke. I validate a particular field when focus from that field goes away. That's when the user is done typing into that field. I start validating when a user pauses typing for sometime, say 0.5 seconds.   I know the question might be opinion-based, but from the perspective of an End user, what would be the best experience? Please add more options as well, if we can have something better than the above 3 options.


Proof by Induction involving Inequality and Factorials as denominators

Have had a lot of trouble with this question. Cannot seem to use the components from the induction hypothesis properly.   Prove by induction:  P(n): $1+\frac{1}{1!}+\frac{1}{2!}+...+\frac{1}{n!} \leq 3 - \frac{1}{n}$ for all $n \in \Bbb N$  So i'm able to prove the base case:  P(1): $1+\frac{1}{(1)!} \leq  3 - \frac{1}{1} = 2 \leq 2$ is true.  Induction: Assume that   P(k): $1+\frac{1}{1!}+\frac{1}{2!}+...+\frac{1}{k!} \leq 3 - \frac{1}{k}$  is true for some $k \in \mathbb N$  Have to show that  P(k+1): $1+\frac{1}{1!}+\frac{1}{2!}+...+\frac{1}{k!}+\frac{1}{(k+1)!} \leq 3 - \frac{1}{(k+1)}$  So I get up to this step but don't know how to proceed after it: $1+\frac{1}{1!}+\frac{1}{2!}+...+\frac{1}{k!}+\frac{1}{(k+1)!} \leq 3 - \frac{1}{k}+\frac{1}{(k+1)!}$  (using the $3-\frac{1}{k}$ from the induction hypothesis (P(k)) but I have no idea how to start working with with these factorials to arrive at a conclusion that matches the RHS of P(k+1). I'm thinking there's something to do with that $(k+1)! = (k+1)k!$ but can't connect it all.   Any help would be appreciated - I checked everywhere on here and closest question I found that was similar was  question but it involves equality vs inequality. Thanks hopefully can help. I think this is question is unique enough that it shouldn't be a duplicate.


How can I Simulate string_agg function in old Version of SQL Server

I want to group by a table by some columns and show values of other column.in SQL v.2017 I can do that with string_agg function. but my SQL version is 2012.How can I do that...  create table dbo.TaskPeriods (  [id] [int] NULL,  [startDate] [datetime] NULL,  [endDate] [datetime] NULL  )  ------------------------------- insert into test.dbo.TaskPeriods values(1,'2018-07-24 00:00:00.000','2018-07-24 10:00:00.000') insert into test.dbo.TaskPeriods values(2,'2018-07-24 00:00:00.000','2018-07-24 10:00:00.000') insert into test.dbo.TaskPeriods values(3,'2018-07-24 08:00:00.000','2018-07-24 12:00:00.000')  -------------------------------------------------------- select id,startDate,endDate from  test.dbo.TaskPeriods  -------------------------------------------------------- select  min (startDate) ,max (endDate) --,string_agg(id,',')  //How to Do this Without string_agg Function FROM test.dbo.TaskPeriods group by startDate,endDate


How to create an OSX Application to wrap a call to a shell script?

My goal is to include in a zip file what amounts to a shortcut, instead of telling my customer(s) to open up Terminal and run a shell script.  My deployable essentially looks like this:  $ unzip Deliverable.zip  $ cd Deliverable; ls app.jar run.sh   Script in run.sh:  #!/bin/sh java -jar app.jar   There's a lot more in the directory; suffice to say I need to run the script from the directory Deliverable since I need to access paths relative to it.  However, I can't guarantee where a customer is going to open Deliverable.zip (could be home directory, could be right in the Downloads directory, etc.)  I found  that describes how to create a new workflow in Automator, then save it as an application to launch a shell script.  I tried to do that to wrap run.sh but it says it can't find run.sh.  Somebody suggested I use applescript and also sent me a link to how to use applescript to switch into the current directory; there's an applescript "action" in automator; so I made a new workflow with that, and saved it as an application.  This is what that looks like:    The code:  on run {input, parameters}     tell application "Finder"         set current_path to container of (path to me) as alias     end tell      do shell script "java -jar app.jar"       return input end run   And this is the error I get when I run it:    C'mon, this should be pretty simple.  What I am doing wrong here?


For EC2 and RackSpace Cloud: Is there a Windows equivalent of Unix 'CPU steal time'?

has a great write up relevant for hyper-V. But it is very hyper-V specific. It does not address how to measure cpu steal on Win servers in EC2 and RS Cloud environments (I have tried the steps there, and they do not apply -- the counters are not available,and I have not spotted similar counters with diff names)  Question is: How do I measure it on win2008 and win2012 servers hosted on EC2 and Rackspace clouds?  I understand there may be no explicit answer to this question (e.g. a performance counter or such may not be available on Xen). So then interpret the question in a more meta manner: "How do I measure CPU Steal?" As there appears to be no explicit way to measure it, what is an effective implicit way?  Additional: Like on other cloud platforms, you can spin up 5 instances on rackspace cloud, and see wildly different performance on each. Because.... noisy neighbors.... so how to directly measure this, from a CPU and networking perspective?


I have a very simple MySQL table where I save highscores. It looks like that:  Id     Name     Score   So far so good. The question is: How do I get what's a users rank? For example, I have a users Name or Id and want to get his rank, where all rows are ordinal ordered descending for the Score.  An Example  Id  Name    Score 1   Ida     100 2   Boo     58 3   Lala    88 4   Bash    102 5   Assem   99   In this very case, Assem's rank would be 3, because he got the 3rd highest score.  The query should return one row, which contains (only) the required Rank.


How to show that every nonempty $X \subset \mathbb N$ has an $\in$-minimal element

I am trying to prove the following:     Every nonempty $X \subset \mathbb N$ has an $\in$-minimal element.   Proof: Take some $n \in X$. Then $\min \{ n \cap X \} = \min \{ X \}$.  Is this ok or should it be more detailed?


Is there an efficient way (algorihtm) to compute the solutions of the congruence $x^n\equiv a \pmod p$?   $n\in \mathbb{N}$ $a\in\mathbb{Z}_p$ $p$ is a large prime number   Note that:   By efficient I mean computationally efficient even when the given prime $p$ is appropriate for use in cryptographic protocols (hard to find discrete logarithm in $\mathbb{Z}_p$) We do not know the prime factors of $p-1$.   It’s easy to find one solution when $\gcd(n,p-1)=1$.  I think this should be as hard as finding a Discrete Logarithm or as Factoring. Any ideas ? Thank you for your time.


Why are useful questions on StackOverflow being closed as non-constructive?

Useful threads are being closed as "not constructive:"     This question is not a good fit to our Q&A format. We expect answers to generally involve facts, references, or specific expertise; this question will likely solicit opinion, debate, arguments, polling, or extended discussion. See the .   For example,  was very useful for me since I am new to obfuscation and the question gave me a start. Also that question has lots of votes and bookmarks - these alone are the  markers of usefulness. The question is closed anyway. No idea why.  Same happened to my question, , which received one bookmark immediately.  I was waiting for an answer with the two products downloaded and installed.  I desired that experienced people would share their thoughts and point me to the better one. No. Closed. I.e. I must go to some other forum and ask there or I must search on Google and write down the pros and cons of each myself. I am not asking questions just because I have tons of time and want to chat; I need an answer, that's why I am asking. I am asking because I think that SO has the most professional people to answer and because I didn't find a good answer in Google.  I saw other questions closed which I myself found to be useful and I bookmarked some of the closed questions.  UPDATE  If I want people who have an experience which I do not have with some software products and I want to see which product is better in the terms of usability and reliability, not just better in terms of the price or has a better official website or better described on the official website, how do I ask this question? Or is this a question which I cannot ask on SO? I.e. this sort of information is not available on SO?  Is this one breaking the rules as well:  ?


How to schedule python job to run every hour accurately with the schedule package

I am using the schedule python package and would like to run a job every hour at the :00 mark.  Is this possible?  This is the code I have right now:  def schedule_jobs(self, loop):     logging.info('Starting scheduler...')      schedule.every(1).hours.do(self._pldown_runner.run_pldown_job, loop)      while True:         schedule.run_pending()         time.sleep(1)   The problem with this is that it runs the job every hour starting from the minute it was actually executed.


PHP: Using interfaces for dependency management

Currently I am investigating several ways of handling dependencies in PHP – stuff like Dependency Injection, the Service Locator pattern and the different implementations of these.    One common thing that is also the point of this question is the use of interfaces. Let's say I wrote a class the stores & retrieves some data from somewhere (doesn't matter for that example):  class DataStuff {     public function store($data)     {         // Do stuff     }      public function retrieve($id)     {         // Do other stuff     } }   When I want to make this class available for other developers to use or for use in other projects, I've read it's recommended to use an interface, which is then implemented by my actual class:  interface DataStuffInterface {     public function store($data);     public function retrieve($id); }  class DaDataStuff implements DataStuffInterface {     // Same as above }   Why is it recommended to use an interface like this?  I know that is has something to do with type hints/Dependency Injection, because stuff like this can be done with it, but I don't really get the point of it:  public function __construct(DataStuffInterface $dataStuffInterface) {     // Do something here }   Where would I place code like this – does is have something to do with factories? Why shouldn't I just do it like this:  public function __construct(DataStuff $dataStuff) {     // Do something here }


I'm having trouble understanding the ROC curve.  Is there any advantage / improvement in area under the ROC curve if I build different models from each unique subset of the training set and use it to produce a probability? For example, if $y$ has values of $\{a, a, a, a, b, b, b, b\}$, and I build model $A$ by using $a$ from 1st-4th values of $y$ and 8th-9th values of $y$ and build model $B$ by using remained train data. Finally, generate probability. Any thoughts / comments will be much appreciated.   Here is r code for better explanation for my question:  Y    = factor(0,0,0,0,1,1,1,1) X    = matirx(rnorm(16,8,2)) ind  = c(1,4,8,9) ind2 = -ind  mod_A    = rpart(Y[ind]~X[ind,]) mod_B    = rpart(Y[-ind]~X[-ind,]) mod_full = rpart(Y~X)  pred = numeric(8) pred_combine[ind]  = predict(mod_A,type='prob') pred_combine[-ind] = predict(mod_B,type='prob') pred_full          = predict(mod_full, type='prob')   So my question is, area under ROC curve of pred_combine vs pred_full.


For example I need to specify a term x subscript a subscript b.  For a x subscript a, I can write it as x_{a}. However, x_{a}_{b} is not supported. How do I do that?


My program runs fine under eclipse. If I open it with the textPad and compile it, I get this message:     Note: C:\Users\Aezur\Desktop\Project2\SummerQ1.java uses unchecked or   unsafe operations. Note: Recompile with -Xlint:unchecked for details.   It says that has compiled successfully, but it doesn't run.  Any ideas?


Identify this insect, found in Central Vietnam, with long antennae, black wings, and red body

Last year this insect landed on my hand when visiting the My Son city ruins in Central Vietnam. I've been trying to identify the insect, but until now without result.  Can you help me? Or do you know who could?


How we show that $Z := \{(x, y, z) ∈ R^3 | x^2 + y^2 − z^2 = 0\}$ is not a manifold (even it is not a topology manifold)

can anyone help me to prove that $Z := \{(x, y, z) ∈ R^3 | x^2 + y^2 − z^2 = 0\}$ is not a manifold (even it is not a topology manifold)?


What are the alternatives to Ubuntu One?

Since canonical is  Ubuntu One, what are the possible alternatives?  I currently use Ubuntu One as a backup service for my Documents folder and various other folders I deem important. Of course I have backups on an external hard drive as well, but nevertheless, I find Ubuntu One to be very useful. What I'm especially looking for is a cloud service that does not need a special folder (such as a dropbox or google drive folder); something that is able to integrate into my own file system and syncs just any folder I want to.   I am aware that this question is rather subjective, but I do guess many people who have used Ubuntu One are now in the dark.


Cokernel of injective endomorphisms of a finitely generated free abelian group

By $\text{GL}^+(n,\mathbb{Z})$ we mean the set of $n×n$ invertible matrices with positive determinant and entries from $\mathbb{Z}$.  For given $A \in \text{GL}^+(n,\mathbb{Z})$ let  $F_A=\mathbb{Z}^n/A\mathbb{Z}^n$ denote the cokernel of $A$.  I would like to compute $|F_A|$. How does one do this?


Are there any other uses for a Pokeball besides capturing and storing Pokemon?

Can a Pokeball be used for things other than storing pokemon?   Like a "" from Dragon Ball or even to imprison humans?


If $K \subset L$ are number fields and $I$ and $J$ are ideals of $\mathcal{O}_K$, then I'm trying to prove the statement  $$I\mathcal{O}_L | J\mathcal{O}_L \implies I|J,$$  where the first division occurs in the ring $\mathcal{O}_L,$ while the second division occurs in the ring $\mathcal{O}_K$.   My initial thought was to try and factor $I = P_1^{a_1}\cdots P_n^{a_n}$ as a product of prime ideals. Then each of these primes will potentially split in the ideal $I\mathcal{O}_L$ to give the factorization   $$I\mathcal{O}_L = (Q_{11}^{e_11}Q_{12}^{e_{12}} \cdots Q_{1m}^{e_{1m}})^{a_1} \cdots (Q_{n1}^{e_{n1}}\cdots Q_{nr}^{e_{nr}})^{a_n}  $$ where the $Q_{ij}$'s denote the splitting of the $P_i's$. Now since $I\mathcal{O}_L | J\mathcal{O}_L$, all of the $Q_{ij}'s$ must appear in the factorization of $J \mathcal{O}_L$. Since each $Q_{ij}$ lies above a unique prime $P_i$, is this enough to imply that each $P_i^{a_i}$ must divide $J$ and hence $I|J$?   If this isn't correct, is there any hint that could be given to send me on the right track to completing this proof?


An exercise I was given read: "Let A be any (possible infinite) set. Argue by contradiction to show that there is no surjection from A to $\{0,1\}^A$. "  Am I right to think this means that the set A is countable and that the exercise is showing that $\{0,1\}^A$ is un-countable or have I missed something?


How addEventListener('mousemove') recognize ctx object?

var d = document.getElementById('draw'); d.addEventListener('mousedown', function(e) {    ctx = d.getContext("2d");    var flag = true;    ctx.beginPath();    ctx.lineWidth = "10"    ctx.strokeStyle = "green";    ctx.moveTo(e.clientX, e.clientY);     d.addEventListener('mousemove', function(e) {        if (flag == true) {            ctx.lineTo(e.clientX, e.clientY);            ctx.stroke();        }        d.addEventListener('mouseup', function(e) {            flag = false;        });    }); });  I'm doing 30 days javascript challenge and have a problem with respect to the above code. The addEventListener function('mousemove') can recognize ctx object. I thought the function cannot recognize ctx since no arguments have been passed to the function. If I take the function out of the outer function(mousedown) and then an error occurs. Any help would be appreciated. Thanks


Which Stack Exchange should I use for cyber security questions or in other words, is there a Stack Exchange like Stack Overflow, but for ethical hackers? In my case, I'm starting into the cybersec world and as a beginner I get to tons of difficulties and mostly errors with the linux ecosystem (Kali Linux) and more over with software that's related to cybersec. EXAMPLE:  Having problems installing certain packages for "Kali Linux", like wifite2 or hashcat.  Getting errors no one in the tutorials is getting when installing a certain package which doesn't come with the OS...  Want to learn how a certain software is properly used "hashcat" for example.  Having difficulties understanding the way a certain software works..


Title says it all, I just want to know how to factor $(x+y)^4+x^4+y^4$. I only know that it's possible to factor, but got no idea how to do it. If it were a single-variable polynomial I could try to find rational roots or something, but I'm lost with this one.


I'm trying to make a 1.9 map where it gives a player a sunflower (double_plant) with a yellow colored name "Quest Token", and a lore saying "Use this to trade with Quest Villagers". How would I do that? My original commands were:  /give @a double_plant 1 0 {display:{Name:"§r§eQuest Token,Lore:"Use this to trade with Quest Villagers"}} /give @a double_plant 1 0 {display:{Name:"&r&eQuest Token,Lore:"Use this to trade with Quest Villagers"}}


What’s the right inflection for the bracketed verb in “He asked what time the train [was/will/be] leaving”?

I was conducting a language assessment test when I was asked to fill out a clause:    He asked what time the train [ was / will / be] leaving.   I would have chosen be to form a subjunctive clause, had the sentence been in the present tense. But now that it is in the past form, I had a hard time deciding. Can be be used, too, here? Or does one have to use was, which would have been my hasty answer in the first place, but forfeiting the possibility to distinguish a subjunctive?  Looking forward to a informative discussion!


Snape was literally Voldemort's right-hand man. He ends as somewhat of a hero in the series. Despite having a desire to respect him, I always remember he must be quite the killer to supplant Bellatrix, Malfoy, and other Death Eaters. Did Snape kill a lot of people?


Are two objects equivalent in a category when their hom sets are isomorphic?

For instance, if, for all $a$ in a category $C$, $\hom(a, b)$ is equal to $\hom(a, c)$ when all instances of $c$ are replaced by $b$ in the latter, does this imply equivalence of $b$ and $c$ in $C$? If so, is this a necessary condition for equivalence of objects in $C$?


TWRP createTarFork() error 255 when backing up data

I have installed FreedomOS on my OnePlus 5. I'm not sure if this is related to FreedomOS, but when I try to make a backup in TWRP with data, system, and boot, it has an error with createTarFork() shortly after it gets to backing up data. It also says 'read only filesystem' when I try to open Terminal from Advanced and run 'cd /data/media/0/TWRP/BACKUPS/bad7d639 && rm -rf backup-name'. What can I do to fix this and why is this happening?


Asking if it would be better to install Ubuntu and through virtualbox handle Windows 10 instead of dual booting my pc

I recently found out the ability to use virtual machines instead of dual installation Ubuntu and Windows. Thinking of installing just Ubuntu, and through virtualbox have a Windows installation. What are the pros of cons of this? Thank you for any insight!


How to create a bootable USB with multiple ISO images in it

What I want is to create a bootable pen drive that shows GRUB menu and I can select any of the several bootable systems from there to install/run. I have several ISO images that I want to install in the USB like Ubuntu, Fedora, System Rescue CD, Windows XP and Windows 7 (The windows versions are optional, mostly am looking for a multi installer for Linux distros, specially Ubuntu version)  The default Startup Disk Creator only works with Linux Images and only 1 at a time (At least for the mean time. If it allows more systems and multiple ISOs it would be awesome)  What method exists that I can use step by step to create a bootable USB Drive with multiple images than can be booted from the USB and selected from GRUB. It must support Windows Images and Linux Images.  Alternatively, is there also a way to have multiple versions of the Ubuntu installation ISO on same USB Drive, such as, when booting from it, I get to choose what Ubuntu version and architecture to install, for example:     BOOT MENU   Ubuntu 12.04 32 Bit   Ubuntu 12.04 64 Bit   Ubuntu 12.10 32 Bit   Ubuntu 12.10 64 Bit   UPDATE: Wanted to add that the English version for the post mentioned by daithib8 is here:


Jquery not firing li click which ul list is dynamically filled

The problem is that jQuery doesn't fire when ul li is clicked. When I fill ul as static there is no problem with firing. But if I fill ul list dynamically from the database with getJSON function li click not firing.List was filled but li click not firing. I need your help to understand what is the problem.   HTML:

Çukurova

  <input type='checkbox' id='chkSemt61'  class='big-checkbox'>Mahfesığmaz

  <input type='checkbox' id='chkMahalle161'  class='big-checkbox'>Belediyeevleri Mah.

  <input type='checkbox' id='chkMahalle162'  class='big-checkbox'>Beyazevler Mah.

  <input type='checkbox' id='chkMahalle163'  class='big-checkbox'>Esentepe Mah.

   jQuery:  $('#ulListMahalle').on('click', 'li', function () {     console.log("li clicked"); });   I fill ul list dynamically with getJSON like that :    $.getJSON("../Ilanlar/GetSemtMahalle", { ilceIDs: ilceIDs }, function (data) {              var ilceName = ""; var semtName = "";              for (var i = 0; i < data.length; i++) {                 if (data[i].Ilce != ilceName) {                      if (i != 0) {                         htmlText += "

";                      }                      htmlText += "

" + data[i].Ilce+"
";                      htmlText += "
";                 }                 if (data[i].Semt != semtName)                 {                     if (data[i].Ilce == ilceName) {                         htmlText += "

";                      }                     // htmlText += "
" + data[i].Semt;                     htmlText += "

  <input type='checkbox' id='chkSemt" + data[i].SemtId + "'  class='big-checkbox'>" + data[i].Semt + "
  ";                     semtName = data[i].Semt;                    htmlText += "
";                 }               //   htmlText += "
" + data[i].Mahalle + "
";                 htmlText += "

  <input type='checkbox' id='chkMahalle" + data[i].MahalleId + "'  class='big-checkbox'>" + data[i].Mahalle + "

  ";                  ilceName = data[i].Ilce;                  if (i != data.length - 1) {                     if (ilceName != data[i + 1].Ilce)                         htmlText += "

";                 }             }              mainDiv.html(htmlText);            // console.log(htmlText);         });


Is there an easy way to work out the Big O value for time and space complexity?

I have been learning about sorting algorithms and understand the idea of time and space complexity. I was wondering if there was a fairly quick and easy way of working out the complexities given the algorithm (one that may even be quick enough to do in an exam) as opposed to learning all of the complexities for the algorithms.  If this isn't an option, is there an easy way to remember or learn them for some of the more basic sortings algorithms such as merge sort and quicksort.


Do the Faceless Men take more than just a face?

Up until "Dragonstone" (Game of Thrones, S07E01) we have only seen faceless men change faces, but when Arya takes on the 'Face' of Walder Frey she assumes more than just his face. She takes on his voice, mannerisms, stature, and posture. Certainly, some of that can be mimicry (changing one's voice, etc), but when Arya (as Walder) stands to make a toast she is like him in more than just 'face', we get an especially good view of the hands and his height.   So, how* does the 'magic' of the House of Black & White/The Many Faced Gods work in respect to this? Does putting on the face of another grant one more than just a face?  Note: other questions bring into question how or whether Arya still has access to that magic. For the purpose of this question let us assume that she does.  *Edit: By "how" what I mean is 'to what extent' or 'how far does it go'. (not by what 'magically principal' (ie is it a transmutation or a glamour). The reference that points out that memories even come with it. The names "The Faceless Men" and "The Many-faced God" focus our attention on the 'facial' aspect but the 'magic' really appears to cover allow the 'wearer' access to the identity, in both mind and body.


How to make a full Ubuntu install with a LiveCD-like bootloader?

Interestingly, on my Surface Pro 3 a LiveCD installation of Ubuntu (15.10) would boot without any issues.  However, a full install on a USB3 SSD, (either in UEFI or non-UEFI mode) with or without Secure Boot would fail to load. I made the installations by installing them through Virtual Box and having the SSD exposed to the Guest OS (Ubuntu Installer Disk).  Does anyone know what the difference in the boot chain is for LiveCDs and full install? Can I get a full install with a LiveCD-like boot chain so that it would boot on my Surface Pro?


ReactJS post increment does not work in setState

While working with ReactJS setState method to update state I observed that post increment operator was not working(did not get any error as well) so I had to use + 1 instead for the same. Any idea why this behaviour as I am new to React and got shocked to learn this.  Here is my code: This did not work:  this.setState((prevState) => ({       left: prevState.left++ }));   This worked:  this.setState((prevState) => ({       left: prevState.left + 1 }));


Determine the density function for coefficients of equation

Both roots $x_1$ and $x_2$ of a square equation $x^2+ax+b=0$ can take any value from $-1$ to $1$  with equal probability . Determine the probability densities for coefficients $a$ and $b$.   I think I should use the properties of Vieta's theorem then $x_1+x_2=-a$ and $x_1\cdot x_2=b$.  And I don't know how to solve it further


In the Die Hard series, John Mcclane often uses this phrase before delivering the punch-blow that exterminates whatever he's aiming to blow up. But Mcclane ain't from Texas or anywhere in the Mid-West, but from New York. Sure the word after this phase (MoFo) is too common for a New York detective, but what is "Yippee-ki-yay" ?


Levi Civita and Kronecker Delta identity

One of the popular Kronecker delta and Levi-Civita identities reads $$\epsilon_{ijk}\epsilon_{ilm}=\delta_{jl}\delta_{km}-\delta_{kl}\delta_{jm}.$$ Now, is there an intuition or mnemonic that you use, that can help one learn these or similar mathematical identities more easily? Also, what is the motivation for expressing Levi-Civita symbol in terms of Kronecker Delta in the first place?


Can I have a public APEX REST API e.g. APEX REST api that is accessible without authentication?


How Could Hogwarts Have Realistically Accommodated the Basilisk 800 - 1000+ Years Ago?

This is the first of a three-part question on the basilisk plot in Harry Potter and the Chamber of Secrets.  Out of all the Harry Potter books, Chamber of Secrets is the most problematic for me as far as continuity and plot goes. I have issues with the whole basilisk plot. I have a set of three questions regarding Chamber of Secrets that I'm looking for CANON COMPLIANT explanations for. By "canon compliant", I mean within the spirit of canon, answers directly from the book(s), or quotes from J.K. Rowling.¹    In Chamber of Secrets the basilisk moves about the castle through the plumbing. However, if Hogwarts was built 1000+ years ago, that would precede indoor plumbing. How can this be explained, that the castle has original indoor plumbing? How could the Founders have anticipated this innovation? The basilisk is described as very large: "as thick as an oak trunk" (CoS - page 318 - US Hardcover) and "able to grow up to fifty feet long" (FBAWTFT - page 3 - Scholastic) Would a snake this large be able to feasibly fit through standard-sized pipes used for indoor plumbing, even pipes sized to accommodate Hogwarts? At the point indoor plumbing was installed in Hogwarts, how is it that the entrance to the Chamber of Secrets wasn't obvious and easily discovered by those installing the indoor plumbing? How could sinks be installed above the entrance, complete with a faucet marked with a serpent, indicating the entrance, without anyone knowing the significance of the serpent on the faucet?    How could Hogwarts have feasibly accommodated a basilisk 800-1000+ years ago, presumably without indoor plumbing?  ¹ I find the Harry Potter Wiki to be inconsistent and oftentimes incorrect. I am not looking for any answer(s) sourced from the HP Wiki unless Wiki itself backs that precise fact with explicit canon quote. Just an FYI.


I need the word "Chapter" in the picture below to stop at bottom and top of the black square. The size of the letters in "Chapter" needs to be the same size as it is now, but I would like there to be eactra white space between each letter in the word.  \documentclass[oneside,10pt,oldfontcommands,standalone]{memoir}    \usepackage[T1]{fontenc} \usepackage{amsmath} \usepackage{fix-cm}       \makeatletter \newcommand\HUGEr{\@setfontsize\Huge{50}{60}}  \makeatother    \usepackage{tikz} \makechapterstyle{box}{     \renewcommand*{\printchaptername}{}     \renewcommand*{\chapnumfont}{\normalfont\sffamily\HUGEr\bfseries}     \renewcommand*{\printchapternum}{         \flushright         \begin{tikzpicture}         \draw[fill,color=black] (0,0) rectangle (2cm,2cm) node[color=white]  (test) {};         \draw[color=white] (1cm,1cm) node { \chapnumfont\thechapter };         \draw[color=white] (-0.5,0) rectangle (-0.1,2) node[midway,rotate = 90,color=black] () {Chapter};         \end{tikzpicture}     }     \renewcommand*{\chaptitlefont}{\normalfont\sffamily\HUGE\bfseries}     \renewcommand*{\printchaptertitle}[1]{\flushright\chaptitlefont##1} } \chapterstyle{box}  \begin{document} \chapter{Introduction}   \end{document}


If I have a string like this:  var str = "play the Ukulele in Lebanon. play the Guitar in Lebanon.";   I want to get the strings between each of the substrings "play" and "in", so basically an array with "the Ukelele" and "the Guitar".  Right now I'm doing:  var test = str.match("play(.*)in");   But that's returning the string between the first "play" and last "in", so I get "the Ukulele in Lebanon. Play the Guitar" instead of 2 separate strings. Does anyone know how to globally search a string for all occurrences of a substring between a starting and ending string?


How can I change the arrow color in beamer? by default they're blue triangles  I tried  \setbeamertemplate{itemize items}[triangle, red]   and  \setbeamertemplate{itemize items}[triangle]{\color{red}}   I want to make this for all slides in my presentation.  (Note to self: 20 years coding experience and nothing in Latex is where I expect it to be).


Apollonius circle, its radius and center

I've got the following set: $\{|z-a|=k|z-b|\}$, where z is a complex number, a an b are fixed, and $k>0$,$k \ne 1$. I need to prove that this is a circle (called Apollonius circle). I also have to prove that this circle's radius is equal to $k|a-b||1-k^2|^{-1}$ and it's centre is $(a-k^2b)(1-k^2)^{-1}$. I don't know what to do, I've tried to work with analytic circle equation ($|z-c|^2=r^2$), substituting given radius and center, but it didn't work. I also tried to square both sides of the first given equation ($|z-a|=k|z-b|$), which usually works with complex number, but also didn't get any result... Can somebody show m how to solve this problem? I will be very grateful.


What is the source of this clause, often used to mark the completion of something?

Seems everybody knows  by ear, even its rhythm is very suggestive.  I wrote down a version in C Major, it look like this:    The Lilypond source is  \relative g' { \key c \major \time 2/4 c g8 g as4 g r b c }   I tried a web search with the note names and a Google image search with the above image, both resulted in nothing useful. From getting the source of this snippet, I hope to also get the information if this sequence is somehow copyrighted. Thanks for you help!


I recently reinstalled iTunes and I noticed something peculiar. The "original" version of iTunes has a user in the permissions known as "wheel" that is set to "Read Only". I dragged this version of iTunes to the trash and installed a new copy, and when I look at the properties for iTunes it no longer says wheel, but rather just admin.  Here is a screenshot with the new version (left) and the old version (right):    What is the "wheel" user"? How is it set (I can't seem to set it in the GUI)? Why would the permissions be different now? It's not a problem, I'm just terribly curious.


What is a good grade for an MS student expecting to apply for a PhD in a top-tier school?

Although I understand that getting an admission into a PhD program depends on many factors, for example--BS and MS GPA, number of journal papers and their quality, number of conference papers and their quality, GRE, Statement of Objective, job experience, profile of other applicants, funding situation etc-- what should be the GPA of an MS student in the US, who is expecting to do a PhD in Mechanical Engineering in any of the top 30 grad schools?  Thanks in advance!


Typesetting long division with tabular and overlining repeating part

I used some of the solution proposed in this post:    and my code is as follows:  \documentclass{standalone} \begin{document}  \begin{tabular}{c*{11}{@{\,}c}}       2&:&7&=&0&,&$\overline{2}$&$\overline{8}$&$\overline{5}$&$\overline{7}$& $\overline{1}$&$\overline{4}$       \\       {\color{red} 2} &{\color{red} 0 } & &&&&&&&&& \\       1 & 4 &&&&&&&&&&  \\  \cline{1-2}        & 6& 0 &&&&&&&&&  \\        & 5 & 6 &&&&&&&&  \\   \cline{2-3}        &  & 4 & 0 &&&&&&&  \\        &  & 3 & 5 &&&&&&&  \\  \cline{3-4}        &  &      & 5 & 0 &&&&&& \\        &  &      & 4 & 9 &&&&&&  \\  \cline{4-5}        &  &      &   & 1 & 0 &&&&& \\        &  &      &   &   & 7 &&&&& \\ \cline{5-6}        &  &      &   &   & 3 & 0 &&&& \\        &  &      &   &   & 2 & 8 &&&& \\  \cline{6-7}        &  &      &   &   &   & { \color{red} 2} &{\color{red} 0} &&&     \end{tabular} \end{document}   The goal is to show the repeating decimal part with overline over the repeating decimals. The code does that, but each decimal is overlined in isolation, but I want a continuous overline!  But that does seem to infer with the mechanics of tabular ...


University learning over online learning

What are some advantages of learning on-campus that one does not get from learning online?


Is there an easy way to mass download SRTM data?  The data is published for download , but it's sliced into thousands of small files, and I don't see an FTP option for more efficient downloading...  Another issue is that the server seems to die (or run out of bandwidth) when I use a download manager like the "DownThemAll" Firefox extension to get them.  Is there a better resource for getting this data?


What's up with the operating voltages 5 V, 3.3 V, 2.5 V, 1.8 V, etc.?

Integrated circuits seem to have standard voltages of 5 V, 3.3 V, 2.5 V, 1.8 V, etc.  Who decides these voltages? Why do smaller devices require lower voltages?


Let $T$ be an invertible linear operator on a finite-dimensional   vector space $V$. Prove that the eigenspace of $T$ corresponding to   $\lambda$ is the same as the eigenspace of $T^{-1}$ corresponding to   $\lambda^{-1}$.   Let $T$ be a linear operator on a finite-dimensional vector space $V$. Let $E_\lambda(T)$ denote the eigenspace of T. How can we conclude $E_\lambda(T)=E_{\lambda^{-1}}(T^{-1})$?


Efficient algorithms to split and join lines?

Referring to the Figure below:     How to efficiently join segments into lines?   How to efficiently break lines into segments?     The above will be applied million times.


List the hardware info and status in my computer

I was wondering how to list all the hardware info in my computer?   Both terminal and GUI solutions please. Is there a single utility to monitor most hardware's working status? Just like some software in Windows?   Thanks and regards!


Why do some websites show the company name next to the URL?

Some websites show the company name next to the URL (in Chrome) and some don't.  How do I set this up for my website? Is there a reason why or why I wouldn't want to do this?


Community user instantly rejected suggested edit?

No, this isn't another user improving the edit. Sorry to those who thought they could get easy rep :)  Over on Physics.SE, I made a suggested edit - . I admit that it wasn't the best edit (I made a mistake in the formatting), but the Community user just came along and casted a binding reject vote. Now, I know that the Community user does this when I am reviewing edits on sites where I'm 2k (here and SO), and I click the Improve button and deselect the 'this edit is helpful' checkbox. When this happens, however, the Community user rejects the edit, then another entry for the user that chose the improve option is also show above the binding reject vote. That's not what happened here - I suggested the edit at 20:45, and the CU rejected it at... 20:45. No entry for someone clicking the Improve button. Did the bot gain intelligence and is stalking me? Should I be worried? Does someone at SE need to taze the server that is Community?


The other day, my soldering iron tip accidentally touched a plastic cable, so I quickly tried  to remove the plastic stuck to my tip using a tester lying nearby. I Soon discovered that the tip was live as the bulb in the tester glowed. I then disconnected the power supply and then check the connectivity of each of the plug to the tip, there was no short between the plug and the tip. I tried to touch the tip when it was on and I couldn't feel anything. I tried hooking up a multi-meter as well which showed about 9V between the tip and ground. Should I be worried about using my soldering iron? Is it safe to use it?


Recover SanDisk SSD PLUS 480GB Internal SSD - SATA III 6 Gb/s, 2.5"/7mm - SDSSDA-480G-G26

Accidentally formatted lost data my SanDisk SSD PLUS 480GB Internal SSD - SATA III 6 Gb/s, 2.5"/7mm - SDSSDA-480G-G26  so I need to recover los data my SanDisk SSD PLUS 480GB. any suggesion?


Convergence of terms in Cauchy product by taking average

Problem. Let $(a_n)_{n=0}^\infty$ and $(b_n)_{n=0}^\infty$ be sequences of real numbers such that $\displaystyle\lim_{n\to\infty}{a_n}=a$ and $\displaystyle\lim_{n\to\infty}{b_n}=b$. Show that $$\lim_{n\to\infty}\frac{1}{n+1}\sum_{k=0}^{n}{a_kb_{n-k}}=ab.$$   My Attempt. It is trivial that $\displaystyle\lim_{n\to\infty}{a_nb_n}=ab$. I was considering to show this in the following fashion:  $$\frac{1}{n+1}\sum_{k=0}^{n}{a_kb_{n-k}}-ab=\frac{1}{n+1}\sum_{k=0}^{n}{(a_kb_{n-k}-ab)}=:c_n.$$ Then it suffices to show $c_n\to 0$ as $n\to\infty$. However, this is a bit difficult as we have $a_kb_{n-k}$ instead of $a_kb_k$, which prohibits us from applying the product limit $ab$. That is the place where I get stuck. Hope anyone have good ideas on this.


Does $\sum_{n=1}^{\infty} \frac{1}{n\sqrt[n]{n}}$ converges?  I said that:  $ \frac{1}{n\sqrt[n]{n}}$ = $ \frac{1}{n^{1+\frac{1}{n}}}$ = $ \frac{1}{n}$ and this is harmonic series which does not converge.  Question is: Is there another way with equation sum series? I thought about dividing it by $1/n$, what do you guys think?  edit: I just noticed that $n^{1+\frac{1}{n}}$ is bigger than one. Which means the series converging. and I was all wrong. is that right?  edit2: $\sum_{n=1}^{\infty} \frac{1}{n\sqrt[n]{n}}$ = Limit of $\frac{1}{n} + 1$. which means it does not converge because the sum of $\frac{1}{n}$ does not converge?


Is there any characteristics difference indicated by this two symbols ?

During study , I am encountered with this two Inverter symbols .  Sometimes this two symbols are usedn in same logic circuit. Though they are working as inverter, I'm guessing there must be some charecteristic differences indicated by this two symbols.Or there is no logic to use two different symbols in same circuit.  Is this symbols indicated different kind of inverters or some different physical properties  ?


I have maybe a simple question. Here two code-snippets to show what I mean:  Example 1:  public interface SomeInterface{   public void someMethod(...); }   Example 2:  public interface AnotherInterface{   void anotherMethod(...); }   So, Example 1 is completely clear to me but Example 2 isnt.    In fact, is there any difference between those two examples expect the public-modifier?     On one hand I found that methods from Interfaces are implicitly public but on the other hand I have found that methods declared in an Interface are "package-public" (I dont now if thats the correct description) - saying these are visible to all classes in the same package as the Interface. For now I am completely confused.. So could someone please explain me whats right?  Thanks anyways.


I am writing an IOS application in Swift (XCode 6) for iPhones and I need to get the telephone number assigned to the telephone running the app.  Searches have not found an answer. Any thoughts?


Let $X_1,...,X_n$ be i.i.d. with common density $$f(x)=\theta x^{\theta -1}I\{x \in [0,1]\}$$ where $\theta >0$. e) Determine whether the MLE is unbiased for $\theta$.  If not unbiased, could you redefine it to make it unbiased?  I found the MLE in a previous part of the problem to be $\frac{n}{-\sum_{i=1}^n \ln(x_i)}$ (I hope I'm correct on this; please inform me if I'm not).  I know for an estimator to be unbiased, $E(\theta)=\theta$, but taking the expectation of the MLE is proving challenging.  Any help?  Or did I just find the MLE completely incorrectly?


Suppose you take a large arbitrary positive electric charge $Q$. Then, given a distance $r$, we can calculate the escape velocity $v$ necessary for an electron to escape the positive charge (just like a rocket trying to escape Earth's gravity).   Could this escape velocity be equal or greater to $c$? Would this create a space from which no negative charge can escape? A sort of "black hole" for negatively charged particles? Does this mean no positively charged particle could enter this space? Is this a sort of "white hole" for positively charged particles? Suppose that you "free" one of the positive charges inside. The electric force would obviously repel it incredibly strongly. I seem to remember something about that the speed of particles falling into a black hole approaches the speed of light. Would a positive particle escaping from our "white hole" appear to be moving at the speed of light, at the event horizon?   I tried to make some back-of-the-envelope calculations, but without taking relativity into consideration I don't really trust the results.


ArcGIS 10 Add-In Does not Work on Other computers

I developed a user form that allows user to edit feature attributes in visual basic 2008. vb.net. The add-in's that I built work great on my computer, but when I tried it on another, it crashes ArcMap.  is this because the DeveloperKit is not installed on the other computer?    I manually add-in the tool (i.e., Customize, Add from file, etc) and it looks like it installs. ArcMap crashes when I click on the button though.  On my computer it work correctly using the same method.   I have uploaded the file to here:


Can the main HNQ page be made more mobile aware?

The mobile aware functionality of Stack Exchange has steadily improved over the years and it’s mainly a joy to use. However, when my fat thumbs stumble onto the main HNQ landing page (stackexchange.com), I’m presented with the desktop version of the site which forces me to squint and pinch my way through the navigation path to find something useable on my phone. Is there a plan to make HNQ more mobile-friendly (or at least easier to get out of)?


I just started with a fresh machine (W10 Pro), and I just ******* it up. I created a user for this computer and it got admin rights. Also, from the users and groups menu, I have seen that there is another "administrator" account there. What I need to do is to have any account with admin rights. I don't have access to a recovery DVD/USB.  So, I've decided to remove admin rights from the user account, but, after doing that, I've realised that the administrator account is blocked, so, I can't change anything, neither create or give admin rights to any account.  I've tried several things from google, like:  Net user administrator /active:yes  which says that I don't have admin rights (yes, windows, I know that). Also, I've tried to use lusrmgr.msc and, again, no admin rights.  I've found also, that I can use shift while rebooting to access some system options, the problem is, whatever I choose, the computer seems to hang and keeps there for a while, doing nothing (no leds blinking) and I need to kill the computer using the power button.  Tried to go to uefi settings using F5, F7, F10 and F11. No luck.  EDIT:  System get stuck while trying to boot from USB/DVD or into UEFI/BOOT options using F9 (as suggested per HP support).  EDIT2: I was able to fix this issue. First, I downloaded a recovery tool from the manufacturer, that boots before the OS and allowed me to disable fastboot "feature". By having the fastboot feature disabled, I was able to use manufactured recovery tool to restore the factory image from the recovery tool.  Thanks everyone for the help.


How to mount problematic internal hard disk using ubuntu 13.10

I have a laptop with windows 7. One day i cannot access windows. So I'M trying to use Ubuntu 13.10 live USB ("try only" version) to retrieve important files in the internal hard disk.  when I try to open the internal hard disk it says that:  Unable to access "86Gb Volume"  Error mounting /dev/sda2 at /media/ubuntu/34BC6628BC65E538: Command-line `mount -t "ntfs" -o "uhelper=udisks2,nodev,nosuid,uid=999,gid=999,dmask=0077,fmask=0177" "/dev/sda2" "/media/ubuntu/34BC6628BC65E538"' exited with non-zero exit status 13: ntfs_attr_pread_i: ntfs_pread failed: Input/output error Failed to read NTFS $Bitmap: Input/output error NTFS is either inconsistent, or there is a hardware fault, or it's a SoftRAID/FakeRAID hardware. In the first case run chkdsk /f on Windows then reboot into Windows twice. The usage of the /f parameter is very important! If the device is a SoftRAID/FakeRAID then first activate it and mount a different device under the /dev/mapper/ directory, (e.g. /dev/mapper/nvidia_eahaabcc1). Please see the 'dmraid' documentation for more details.   Help me, please


I am using the SimpleLightbox plugin () on a test site: .  If you click on one of the pictures, SimpleLightbox opens a larger version in a Lightbox. You'll notice that to close the Lightbox you need to click the white "X" in the upper-right hand corner, but that is directly over the page menu (where the three lines are).  So, I added some code that would remove the navigation bar from the page when the Lightbox loads, which looks like:  $(document).ready(function(){     $(".simplelightbox").click(function(){         $(".burger").hide();     }) });   This works because the code gets executed when someone clicks on one of the Lightbox images with the class "simplelightbox"  The problem I'm having is making the nav bar re-appear.  I have tried:  $(document).ready(function(){     $(".simple-lightbox").click(function(){         $(".burger").show();     }) });   but that doesn't work - the nav bar doesn't re-appear. That one uses class .simple-lightbox (because that is the main class when the Lightbox is showing) - there is also sl-overlay, sl-wrapper, sl-image, and sl-close but none of those worked either.  Anyone have any ideas?  Thanks, Josh


Is there a limit to how early one can apply for a Visa in the United States?

As per  you cannot apply for the F-1 Visa 120 days before the expected starting date on the I-20.  Is there some similar condition for the H1B Visa or the B1/B2 Visa as well?


Pokémon Go. Username, Password, Screen name and player ID

My Pokémon Go account has locked me out and I can’t enter. This has happened very recently. Unfortunately, if I sign up as a returning player, I need my username and password, which I forgot. I would be able to get back my username if I entered the player ID and screen name, but I have no clue on what these two words mean! I really need someone’s help!


I'm a beginning latex user. I have some programming code in my document which I format using the lstlisting environment from the package listings.  However this still allows the code segments to be split into two pieces when placed near the end of a page.  To fix this I also use a figure environment for code. This causes an often recurring pattern:  \begin{figure}[H] \begin{lstlisting} ..code.. \end{lstlisting} \end{figure}   How can I define a new environment for this pattern? I tried:  \newenvironment{mylisting} { \begin{figure}[H] \begin{lstlisting} } { \end{lstlisting} \end{figure} }   However using this environment gave errors all over.


I have been trying to parallelize the following script, specifically each of the three FOR loop instances, using GNU Parallel but haven't been able to. The 4 commands contained within the FOR loop run in series, each loop taking around 10 minutes.   #!/bin/bash  kar='KAR5' runList='run2 run3 run4' mkdir normFunc for run in $runList do    fsl5.0-flirt -in $kar"deformed.nii.gz" -ref normtemp.nii.gz -omat $run".norm1.mat" -bins 256 -cost corratio -searchrx -90 90 -searchry -90 90 -searchrz -90 90 -dof 12    fsl5.0-flirt -in $run".poststats.nii.gz" -ref $kar"deformed.nii.gz" -omat $run".norm2.mat" -bins 256 -cost corratio -searchrx -90 90 -searchry -90 90 -searchrz -90 90 -dof 12    fsl5.0-convert_xfm -concat $run".norm1.mat" -omat $run".norm.mat" $run".norm2.mat"   fsl5.0-flirt -in $run".poststats.nii.gz" -ref normtemp.nii.gz -out $PWD/normFunc/$run".norm.nii.gz" -applyxfm -init $run".norm.mat" -interp trilinear    rm -f *.mat done


Garbled entries on list of figures using subfloat

MWE:  \documentclass[english]{scrbook} \usepackage{graphicx} \usepackage{subfig} \usepackage{babel}  \begin{document} \listoffigures  \begin{figure} \subfloat[Figure A.]{\includegraphics[width=5cm]{test1}} \subfloat[Figure B.]{\includegraphics[width=5cm]{test2}} \caption{Figures A and B.} \end{figure}  \end{document}   Output:   This overlapping only occurs if I use subfloats. Both lualatex and pdflatex give the same result.  I am a LyX user, so I would like to stick to what it offers (subfloats, in the case). Some simple fix in the preamble would be best.


My MacBook Air is giving me static when touching

I know that is because maybe the plug I'm plugin it is not grounded, I have the 3 pin power adapter, I live in Argentina where voltage is 220v from the power plug, is there any way to ground my MacBook in order to not feel that static sensation, because I feel like its gonna broke something on the MacBook.  Is there any wrong on using my MacBook with this static sensation when rubbing it ?


Sed error replacing partial string with variable

I have 3 text files. I want to search file3 for a string in file2 and replace it with a string in file1 in found. I need to append a custom tag from file1 to the end of the string in file3, replacing the partial string found from file2.  file3  aws ec2 create-tags --region us-east-1 --resourcesi-XXXXX --tags Key=Developer Name,Value=XXXXX Key=Resource Group,Value=arn:aws:iam::XXXXX:root aws ec2 create-tags --region us-east-1 --resourcesi-XXXX --tags Key=Developer Name,Value=XXXXX Key=Resource Group,Value=arn:aws:iam::XXXXX:user/user   file2  arn:aws:iam::XXXXX:root  arn:aws:iam::XXXXX:user/user   file1  my_custom_tag_1 my_custom_tag_2   Desired output:  aws ec2 create-tags --region us-east-1 --resourcesi-XXXXX --tags Key=Developer Name,Value=XXXXX Key=Resource Group,Value=my_custom_tag_1 aws ec2 create-tags --region us-east-1 --resourcesi-XXXX --tags Key=Developer Name,Value=XXXXX Key=Resource Group,Value=my_custom_tag_2   I've tried loading the lines from the file into an array and including the index in a sed replace.  sed "s|${file2array[0]}|${file1array[0]}|g" file3.txt   But this returns a "no previous regular expression" error. I've also tried writing the array indexes to unique variables with a for loop and using the same approach above with the variables  sed "s|$var2|$var1|g" file3.txt   This also fails  Interestingly,   sed "s|${file2array[0]}|customtext}|g" file3.txt   fails but  sed "s|customtext|${file1array[0]}|g" file3.txt   succeeds.  Any help is greatly appreciated. Been working on this for dozens of hours now.


Was Air Canada flight AC1074 for April 14, 2020 cancelled?

Was Air Canada flight AC 1074 depart Denver to Montreal cancelled?


Optical physics and principle of reversibility

I know that if a ray is incident at the medium boundary at critical angle, the ray after refraction moves towards the medium boundary. So, is it possible that if a ray is passed through the medium boundary, it will deviate towards the denser medium? if not then can it be called an exception of principle of reversibility of light rays. Please help me through this paradox.


Why "would" instead of "will" in this sentence?

The goal for these negotiations is to reach a mutually-agreed long-term comprehensive solution that would ensure Iranˈs nuclear program will be exclusively peaceful.    what does would imply here? If it implies future, why will has not been used?  A good link teaching would thoroughly would be really appreciated. Specially, distinguishing between the senses of would is not always easy.


Spread operator updates unwanted elements while adding new elements in array(ReactJs)

I am building a matrix calculator as a react app. I have implemented a method that shows the history of every single mathematical operation that the user used, like addition, substraction etc. The problem is that every time a new operation is called and the current matrices change than the previous ones, the history updates its content with the new values.  You can test the app on:   The matrix itself is a class, where is defined a 2d array and its size      this.matrice = [];      for(let i=0;i<arraySize;i++){         this.matrice[i]= [];         for(let j=0;j<arraySize;j++){             this.matrice[i][j]=0;         }     }      this.size = arraySize;   Then to introduce the data to the matrix I use a form:  <input   type='text'                  placeholder='0'   onChange={this.handleChange.bind(this, i, j)}   key={j}               />   The function:  handleChange = (i,j, event)=> {     event.preventDefault();     let x = event.target.value;     this.state.matriceA.setValue(i, j, value); }   By using this function, I insert the value to the matrix.  Now, every time an operation is requested, the matrices used, the operator and the matrix where the result is calculated are stored in an array. This is the function that does that:  var list = [         {             matrixA: matriceA,             operator: semn,             matrixB: matriceB,             matrixC: matriceC //result         }     ]      this.setState({         results: [...list, ...this.state.results]     })   So, the values are now stored in this.state.results and at the end I map through the entire array and display elements:  {this.props.rezultate.map((item, index) => {  ///useless stuff  })}   But the elements shown are not expected to be there, here is an example:    To see, what i am talking about, look to the bottom of the page  As you can see, the last operation, also updated the previous operations, even though it should not have done that.  I do not know what i am doing wrong at this stage, so i am looking forward to hearing from you a solution. Thanks!


Why is Date Time formatting in batch file gives different results?

I have a batch file which creates a backup of some source code folders when run. For back file name it creates a string consisting of current date time.   To get date time string following snippet is used.  SET isodt=%date:~-4%_%date:~3,2%_%date:~0,2%__%time:~0,2%_%time:~3,2%_%time:~6,2% echo %isodt% pause   It gives following output when run on my laptop:  2019_09_12__14_25_01   Recently I ran it on a virtual machine and it gave me following output for same code.  2019_ 0_Th__14_18_18   Why is output not the same? Both are run on Windows 10 64 bit machines.


Moving app data from galaxy phone to tablet

I want to transfer a game with my progress form my phone to my tablet. The game is in my Google play account but it does not show my progress when I open the game. Please help!


Apche2 multiple ssl configuration not working

I have set up two ssl certificates on apache2 but when i enter with domain the first certificate works and when i enter with server ipadress it shows me the same certificate which i have on domain.  I have disabled default and default-ssl vhosts.  Here are my virtual hosts:  <VirtualHost *:443>     ServerAdmin mail@example.com     ServerName example.com:443     ServerAlias www.example.com:443     DocumentRoot /var/www/example.com/public_html     ErrorLog /var/log/apache2/error-log.log     CustomLog /var/log/apache2/custom-log.log common     DirectoryIndex index.html index.php index.xhtml index.htm     #Allow phpmyadmin /usr/share/phpmyadmin     <Directory /usr/share/phpmyadmin>         Options -Indexes FollowSymLinks         AllowOverride None         Order deny,allow         allow from all     </Directory>     <Directory />         Options -Indexes FollowSymLinks         AllowOverride None         Order deny,allow         Deny from all     </Directory>     <Directory /var/www/>         Options FollowSymLinks MultiViews -Includes -ExecCGI -Indexes         AllowOverride All         Order allow,deny         allow from all         LimitRequestBody 104857600     </Directory>      ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/     <Directory "/usr/lib/cgi-bin">         AllowOverride None         Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch         Order allow,deny         Allow from all     </Directory>      ErrorLog ${APACHE_LOG_DIR}/error.log     LogLevel warn     CustomLog ${APACHE_LOG_DIR}/access.log combined      Alias /doc/ "/usr/share/doc/"     <Directory "/usr/share/doc/">         Options Indexes MultiViews FollowSymLinks         AllowOverride None         Order deny,allow         Deny from all         Allow from 127.0.0.0/255.0.0.0 ::1/128     </Directory>      SSLEngine on     SSLOptions +FakeBasicAuth +ExportCertData +StrictRequire     SSLCertificateFile /etc/apache2/ssl/first-ssl.crt     SSLCertificateKeyFile /etc/apache2/ssl/first-ssl.key     SSLCertificateChainFile /etc/apache2/ssl/first-ssl.crt </VirtualHost>   <VirtualHost *:443>     ServerAdmin example@example.com     ServerName 188.226.208.247     DocumentRoot /var/www/     SSLEngine on     SSLOptions +FakeBasicAuth +ExportCertData +StrictRequire     SSLCertificateFile /etc/apache2/ssl/second-ssl.crt     SSLCertificateKeyFile /etc/apache2/ssl/second-ssl.key </VirtualHost>


How to simplify this combinatorial formula and solve the cardinality of the intersection?

Define two sets: $\Sigma_1$ and $\Sigma_2$ where we have that $a$ is  odd (i.e. $a=2n+1$ for some $n\in \mathbb{N}$)  and $b\in \mathbb{N}$, $\Sigma_1 = \Big\{ \frac{2}{a},\frac{2}{a-2},\frac{2}{a-4},...,\frac{2}{a-(a-1)},$ $\frac{2+4}{a+2},\frac{2+4}{a},\frac{2+4}{a-2},...,\frac{2+4}{a-(a-1)},$ $\frac{2+8}{a+4},...,\frac{2+8}{a-2},...,\frac{2+8}{a-(a-1)},$ $\vdots$ $\frac{2+4\lfloor\frac{b}{2}\rfloor}{a+\lfloor\frac{b}{2}\rfloor},\frac{2+4\lfloor\frac{b}{2}\rfloor}{a+\lfloor\frac{b}{2}\rfloor-2},...,\frac{2+4\lfloor\frac{b}{2}\rfloor}{a-(a-1)},$ $\frac{2+4(\lfloor\frac{b}{2}\rfloor+1)}{a+\lfloor\frac{b}{2}\rfloor},\frac{2+4(\lfloor\frac{b}{2}\rfloor+1)}{a+\lfloor\frac{b}{2}\rfloor-2},...,\frac{2+4(\lfloor\frac{b}{2}\rfloor+1)}{a-(a-1),}$ $\frac{2+4(\lfloor\frac{b}{2}\rfloor+2)}{a+\lfloor\frac{b}{2}\rfloor-2},\frac{2+4(\lfloor\frac{b}{2}\rfloor+2)}{a+\lfloor\frac{b}{2}\rfloor-4},...,\frac{2+4(\lfloor\frac{b}{2}\rfloor+2)}{a-(a-1)}$ $\vdots$ $\frac{2+4b}{a},\frac{2+4b}{a-2},...,\frac{2+4b}{a-(a-1)} \Big\}$ and $\Sigma_2 = \Big\{ \frac{2}{\lceil\frac{a}{2}\rceil}, \frac{2}{\lceil\frac{a}{2}\rceil-1},\frac{2}{\lceil\frac{a}{2}\rceil-2},...,\frac{2}{1}$ $\frac{2+2}{\lceil\frac{a}{2}\rceil+1},\frac{2+2}{\lceil\frac{a}{2}\rceil},\frac{2+2}{\lceil\frac{a}{2}\rceil-1},...,\frac{2+2}{1},$ $\vdots$ $\frac{2+2(\lfloor\frac{b}{2}\rfloor-1)}{\lceil\frac{a}{2}\rceil+(\lfloor\frac{b}{2}\rfloor-1)},\frac{2+2(\lfloor\frac{b}{2}\rfloor-1)}{\lceil\frac{a}{2}\rceil+(\lfloor\frac{b}{2}\rfloor-2)},...,\frac{2+2(\lfloor\frac{b}{2}\rfloor-1)}{1}$ $\frac{2+2\lfloor\frac{b}{2}\rfloor}{\lceil\frac{a}{2}\rceil+\lfloor\frac{b}{2}\rfloor},...,\frac{2+2\lfloor\frac{b}{2}\rfloor}{1},$ $\frac{2+2(\lfloor\frac{b}{2}\rfloor+1)}{\lceil\frac{a}{2}\rceil+\lfloor\frac{b}{2}\rfloor-1},...,\frac{2+2(\lfloor\frac{b}{2}\rfloor+1)}{1},$ $\frac{2+(\lfloor\frac{b}{2}\rfloor+2)}{\lceil\frac{a}{2}\rceil+\lfloor\frac{b}{2}\rfloor-2},...,\frac{2+(\lfloor\frac{b}{2}\rfloor+2)}{1}$ $\vdots$ $\frac{2+2b}{\lceil\frac{a}{2}\rceil-1},...,\frac{2+2b}{1} \Big\}$ The question is, how do I determine the cardinality of the intersection of these two sets i.e. how would I compute the value $|\Sigma_1 \cap \Sigma_2|$? Note that duplicates may appear within both sets such as $\frac{1}{2}=\frac{2}{4}=\frac{4}{8}$ etc. Therefore we must make sure that for each fraction $\frac{n}{m}$ we have $\text{gcd}(n,m)=1$. I am aware of the existence of , which really might help here. Unfortunately I struggle simplifying the formulas of $\Sigma_i$'s to simpler forms. My question is if these expressions may be simplified in any way or there is a way of finding the cardinality of $|\Sigma_1 \cap \Sigma_2|$?


Some kinda voodoo, indeed.  Bought a new boot drive, and it's time to use the old drive for data. I thought I'd save some time by just wiping the unneeded system folders, instead of backing up, formatting, and restoring. Wups!  I have a single Adobe file that absolutely will not be deleted. G:\Windows\SysWOW64\Macromed\Flash\flash9.ocx - though it may have started with a different file name. I'm able to rename it, oddly enough.  To be clear, the drive is currently plugged in externally. So I can boot the computer, plug this drive in afterward, and immediately attempt to delete. "File in use" box reads "the action can't be completed because the file is open in another program".  I'd format at this point, but it's my white whale, and I have to know if Adobe has inserted some nasty little registry hack - or whatever it is - making this impossible.  Since I'm sure it'll come up, I've taken ownership of the file - and this was the trick preventing me from deleting anything else on the drive - full rights on the file permissions, you name it, I've fiddled with the file itself.   I'm about to try uninstalling flash from the system drive, in case that aligns the planets properly. Sometimes I wish I were less stubborn, and could just format already.


How can I escape white space in a bash loop list?

I have a bash shell script that loops through all child directories (but not files) of a certain directory.  The problem is that some of the directory names contain spaces.    Here are the contents of my test directory:  $ls -F test Baltimore/  Cherry Hill/  Edison/  New York City/  Philadelphia/  cities.txt   And the code that loops through the directories:  for f in `find test/* -type d`; do   echo $f done   Here's the output:   test/Baltimore test/Cherry Hill test/Edison  test/New York City test/Philadelphia   Cherry Hill and New York City are treated as 2 or 3 separate entries.  I tried quoting the filenames, like so:  for f in `find test/* -type d | sed -e 's/^/\"/' | sed -e 's/$/\"/'`; do   echo $f done   but to no avail.  There's got to be a simple way to do this.    The answers below are great.  But to make this more complicated - I don't always want to use the directories listed in my test directory.  Sometimes I want to pass in the directory names as command-line parameters instead.  I took Charles' suggestion of setting the IFS and came up with the following:  dirlist="${@}" (   [[ -z "$dirlist" ]] && dirlist=`find test -mindepth 1 -type d` && IFS=$'\n'   for d in $dirlist; do     echo $d   done )   and this works just fine unless there are spaces in the command line arguments (even if those arguments are quoted).  For example, calling the script like this: test.sh "Cherry Hill" "New York City" produces the following output:   Cherry Hill New York City


What does “pull sb. out of the hat” mean?

I found the phrase, “pull her out of the hat” in the following sentence of the quote from Frank Bailey, the most relied-upon former aide of Ms.Sarah Palin, whose memoir, “Blind Allegiance to Sarah Palin: A Memoir of Our Tumultuous Years” is due out on Tuesday this week.  “I doubt if there's anything new in this book, just more detailed views of the gruesome story of her rise and fall. What would really be interesting is an account of who made the decisions in the GOP to pull her out of the hat. It certainly wasn't McCain.”  I don’t find the idiom, “pull one out of the hat” in any dictionaries at hand. Does it mean to “pick up” (Sarah Palinfor (vice) presidential candidate) or “remove her from (the candidate seat)? Can somebody teach me the meaning of this phrase?


QGIS-3 Controlling PDF Export Image Quality and Compression

Is there a way of controlling what image compression or quality is used when exporting a PDF in layout composer?  ArcGIS users will be familiar with the options available under the "Format" tab in the ArcMap "Export Map" menu.  Is there a similar level of control available in QGIS 3.10? I found a similar question but it seems dead:


Regex for validate words also with accents

My regex validates words (also containing numbers), but words that have accents are not validating correctly.  /^[a-zA-Z0-9_]*$/i.test(word)   For example:  car => true  plantas => true  avião => false (but this should be also true)   What should I change in my regex to also work with accents?


I am trying to create a short code with a form I have the form displaying ok but I need to be able to pull the price information from sql table as well and show it in a label.  How can i do that using the following code.  <?php /* * Plugin Name: WordPress ShortCode * Description: Fules Plugin. * Version: 1.0  */  // Example 1 : WP Shortcode to display form on any page or post. function form_creation(){     global $wpdb; ?> <form>  Liters:<select> <?php      $sql = 'SELECT liters FROM wp_tfp';      $liters = $wpdb->get_col($sql);  if( $liters ) {    foreach( $liters as $liter ) {          echo '<option value="' . $liter . '">' . $liter . '</option>';   } } ?>  </select> Price: <input type="text" name="price"><br>  </form> <?php } add_shortcode('test', 'form_creation'); ?>


I am writing on a document where I often have the situation that a table is at the end of a page, but then Latex puts the table on the next page. Now the problem is: The text that is supposed to be AFTER(!) the table appears on the preceding page, as there is apparently not enough space for the table. This is of course an awful situation.   Therefore, I either want to have this space on the preceding page left blank and continue with my table on the next page or I want to split my table into pieces (but not manually, as I would then have to adjust this too frquently then)  Does anybody have an idea how I could solve this problem?


I get stuck to differentiate between some common and material noun.  Can material noun be countable?   Are  egg, earth, nail, sun and moon material nouns?  when can I use article in front of a material noun?   I am not a native speaker.   Thanks in advance.


How to determine if two points lie on a vector, given a unit vector

If you have two points, $A$ and $B$, at $(1,1,1)$ and $(1,1,7)$ respectively, and a unit vector $C (0,0,1)$. What's a way to find if unit vector C, will cross B if C extends forever. (Unit vector C has a starting point at A)  Basically, imagine point A is a person, point B is an object. C is a unit vector. Is person A looking directly at object B given A's unit vector?  Since  $A\cdot B = ||A||\;||B||\cos\theta$ could I say, if the dot product of A and B is equal to $||A|| \; ||B||$, then it would mean $\cos θ = 1$, therefore $θ = 0$ and the line crosses B.


Make Windows 10 stop installing driver software automatically

I've upgraded my PC from Windows 7 Ultimate to Windows 10 Pro; overall it seems to be working fine, with small bugs here and there. One thing that I find really annoying is that Windows seems to think it is OK to install drivers and vendor-specific control panels for me.  I've always installed drivers manually to get around having all the bloatware (i.e., Realtek's audio management panels and other vendor-specific tweaking tools).  How do I stop Windows from automatically installing bloat on my custom PC, so that I can use the drivers I've exported from packages and binaries to get around bloats?  If I uninstall everything Windows automatically installed, it seems as if a reboot persists them and installs again.  Preferably I'd like to perform a clean install and have Windows skip installing any drivers automatically. Is this possible?


What happened to the "You're Just Lazy" close vote reason?

...not literally, of course.  But what happened to the previous menu of close-vote options?  I find the current set unsatisfactory. Take  for example.  Obviously, the question is worthless, because it's an exception that even a n00b programmer should be able to debug on his own. There is nothing special about this bug, and it will help no one in the future.  What could I possibly select as a close reason?   duplicate of... - Maybe. There's the classic  which has been linked to . While the debugging techniques are the same, that's for .NET.  Besides, there are any number of other common exceptions / simple development bugs that wouldn't apply. off-topic because...   ... This question was caused by a problem that can't be reproduced or a simple typographical error. While similar questions may be on-topic here, this one was resolved in a manner unlikely to help future readers. This can often be avoided by identifying and closely inspecting  before posting.Notes below....  unclear what you're asking - No, it's clear that the programmer just needs to debug his code. too broad - No, it's quite specific. primarily opinion-based - Nope.   When it was introduced, I was happy to see a "typo" reason, to rid out all the stupid indentation or bracket questions. But... we no longer have a "lacks minimal understanding" reason, which I think is incredibly important. After all, Stack Overflow is here to solve problems that  encounter... not teach users how to code or debug.  So.... what do I pick?  Can we have another revision on the close vote reasons?  I did a cursory search, but couldn't find a Meta post to the intent behind this latest set of reasons. Edit: I believe this is it:     Edit 1/20  Ah, how could I forget about the classic copy & paste homework assignment?      Right or wrong, my close vote was cast with      off-topic because it shows zero desire to actually understand the problem.      we see a moderator closing a question about an incorrect number of function parameters as lacks sufficient information to diagnose the problem. Of course, there probably is sufficient information, and the wording should really be changed to You're too lazy to RTFM.


Calculating area of newly added polygons on same layer?

I have a layer where I had 6 polygons. I then used the field calculator so I could get a column with the area of each of these polygons and I thought this would be applied to any other polygons I made after that, which was not the case since every new polygon appears as "NULL" in the area column. How do I make so the area is calculated automatically for all the rows?


As the question implies, I am talking about the name of this website. It has evidently been formed from 'Stack' & 'Exchange'. But what does it mean and why was this name chosen  ?


Suppose I download a .deb package from a website and install it. (I assume that when I double click the .deb file, the package is installed through a GUI that interfaces with dpkg right?)  How can I uninstall it?


how to vertically top align a slide in beamer?

The following beamer slide (and all other slides) have the text vertically centered. How do I get it to appear at the top of the slide?        \documentclass[sansserif,mathserif]{beamer}        \begin{document}        \begin{frame}{centered frame}       centered text, how to get it to top?       \end{frame}        \end{document}


How to Check the location of a deleted file in CentOS Linux distribution?

I have deleted a file and now I want it on the same place from where I have deleted? How I can check that deleted file in my system from CLI?  I tried find command but end up nothing.


Attempting to remove recent files from Nautilus does not work. At times the monitor goes gray and internal Nautilus error is received.  Is there command line option ? It seems it is a GUI problem.


Does the sentence "I am surprised" have the pattern (S+V+C)?

I am confused about this sentence pattern (S+V+C):   I am surprised [ to see you ].  I am surprised [ at how many have never heard of it ].  I am surprised [ by his response ].  I am surprised [ that some people study the past ].    I think that the sentence "I am surprised" has the sentence pattern "Subject + Verb + Complement". So the phrases following the complement should be adverb phrases, because they modify the complement (surprised), right? But the sentence "that some people study the past" is a nominal clause. It should be unable to modify the complement (surprised). So why are these following phrases able to modify the complement?  to see you at how many have never heard of it by his response that some people study the past


Using ArcMap 10.0  Trying to export a photo that has been taken with a device which is stored inside of a Feature class table. I have tried to export the data using "Right Click>Data>Export Data" This only exports the other data inside the table, such as the date taken and another attribute.  I am trying to export this layer into QGIS so that the raster layer is still available. So you can see the point, click on it and the photo will show, all in QGIS. Unsure on what needs to be done or if this is even possible.  The raster column is removed when exporting it to .dbf or .shp file extension. Something I am missing here?


Why is the prefix "Trans" shortened to "X"?

In technical literature as well as aircraft user interfaces where there is not enough space to write the whole word, the prefix "trans" is shortened to "x".  Transmit -> Xmit  Transfer -> Xfer  I am interested to know what is the origin of this. I am curious because "Ex" and "Trans" do not have a similar sound.