Why do some close or reopen votes show in a timeline as invalidated instead of completed?

Preface:  This question is, IMO, not a duplicate of "", for these reasons:   Only bullet "1." of my question seems to be partially addressed in the above question, which doesn't talk about reopen voting in any way (only about close voting). The above question does ot explain anything about bullet "2." and "3." of my question. The above question in no way addresses the scenario related to example C, where the real answer to that part of my question is included in the comment quoted near the end of my question.     Assume a question which was put on hold as the result of voting via the Close votes review queue (on any SE site), as shown in : below the link to the actual , it shows the typical (in red) "completed".  Similar for the result of voting via the Reopen votes review queue (on any SE site), as shown in : below the link to the actual , it shows the typical (in red) "completed".  However, there are questions where such "completed" is not shown:   Example A where below the  it says "invalidated" (not "completed"): Example B where below the  it says "invalidated" (not "completed"): Example C where below the  it says "invalidated" (not "completed"):   My questions:   What does such "invalidated" actually mean? What are possible cases where this happens? Who or what actually "invalidates" such reviews of close or reopen votes, and why?   Update 1:  My "impression" is that something happens (gets triggered) by a moderator-like intervention, maybe something like "stop this close/reopen voting" and my (next) guess is that such event then pulls the "invalidated" trigger. I may be wrong (just guessing), but that is what I saw happening in various similar cases over the recent past (and via this question I try to understand if there is such a thing, and if so what it is).  Update 2:  The existing answer to my question here, appears to be an answer for Example A and B. But IMO it does stil not explain Example C. So until an even better answer arrives that also explains Example C, I accept this answer.  Update 3:  Note this comment below the accepted answer:     Sorry, I misread the dates. That one got invalidated because of a bug that existed back then (I believe it got fixed last year). Essentially any reopen vote causes the edit to be ignored, but the system only considered reopen votes at least 15 minutes old for review cases. So if the system updated review within that 15-minute, it would think the task is invalid because the edit doesn't qualify and the only reopen vote isn't old enough. It would kill the task and wouldn't recreate it unless a second reopen vote came in. I forget how it was fixed, I think we started ignoring the reopen vote time.   Only this comment should illustrate what I wrote in my "Preface" above ...


WhatsApp doesn’t show usernames on notifications

Today I updated to version 2.18.52 & I can’t see the names of the people who send me a message. The only thing I see is the WhatsApp logo and the word “message”.    I can’t also see the status my friends posts, they all look black. I uninstalled the app, reset my phone & nothing seems to work so far.


How to geometrically prove the focal property of ellipse?

How to prove geometrically that if we have a tangent of ellipse with focus F and F' in point P, that tangent is bisector of the angle between a line joining focus F to point P and the line F'P outside the ellipse?


Unable to print your web pages from Firefox

It is almost two days that the print of your web pages (faces of solved problems) is not possible.  The problem is that only the first page, for example  comes in "print view window" and the other pages could not be printed ( but this only happens in Firefox).  Why is this and can this be fixed?  (This doesn't happen on Chrome)


How do you retrieve items from a dictionary in the order that they're inserted?

Is it possible to retrieve items from a Python dictionary in the order that they were inserted?


How can i make a command stay active after a restart to the computer?

I used a command i saw here to make my touch pad in lenovo 330 to scroll with 2 fingers and it worked exactly as i wanted but after each reset to the computer I need to retype the commend. Can you please tell me how i can make this command stay after i close my computer?


Visited links within spoilers are not hidden anymore

This  contains spoilers. Once you've clicked any of the links, your browser remembers you've visited them and the stylesheet applies new styles to them, which prevent them from being hidden normally by the spoiler:    It's a similar situation for this :


How can i find the mac address on client side i.e. for web browsers?

I need to manage the login activity for this I need the mac address of devices. Using Angular or Javascript?  I have tried getmac npm module.


Root Android virtual device with Android 7.1.1

I'm using the official Android SDK with the Android Emulator to create a virtual Android 7.1.1 (x86). I need to test a number of things, amongst others, some applications require root access to the device.  Now I know that I can adb root and I have a root shell, but that doesn't allow the apps I install to have root access.  I've researched this topic now for a while and have seen various approaches. Most answer haven been posted rather long ago.  I think it's quite odd that there's no option to toggle root - this is after all an SDK.  How do I root an Android virtual device, running Android 7.1.1, effectively allowing installed apps root access?  edit: I'd rather not resort to paid emulators like Genymotion if possible.  edit2: This is solely for personal use.  edit3: Genymotion appears to be a viable solution, as an alternative emulator. How come Android SDK/Emulator does not offers such a feature?  edit4: The answer by  seems to work perfectly fine, however since Android Studio version 3.1 this doesn't seem to be a permanent rooting. Once the AVD is rebooted, root access is gone.


Hide method taking template parameter reference in cpp file

I would like to hide my function taking a template parameter reference in the corresponding cpp file using C++11. But I always end up in a missing reference linker error. It only obviously works if I copy the definition to a.h file but I want to hide the code. Otherwise using a template object as parameter forces me to put a lot of my project code to the header file. Is there any way to archive this?  Related to: . But here the template is typename not a size.    This is my minimal example showing my problem.   b.h  #ifndef _B_EXAMPLE_H #define _B_EXAMPLE_H #include <cstdint> #include <cstring>  template<std::uint32_t T> class B { private:     char x[T];  public:     void add(const char* str)     {         strncpy(this->x, str, T - 1);     } }; #endif   a.h  #ifndef _A_EXAMPLE_H #define _A_EXAMPLE_H #include "b.h" #include <cstdint> class A { public:     template<std::uint32_t T> void foo(B<T>& t); };  #endif   a.cpp  #include "a.h"  template<std::uint32_t T> void A::foo(B<T>& obj) {     obj.add("Top secret"); }   main.cpp  #include "a.h"  int main() {     B<20> bObj;     A aObj;     aObj.foo(bObj);      return 1; }     Edit  Even If this question has already been closed I would like to share my solution here. In my opinion my question is related but not the same.  b.h  #ifndef _B_EXAMPLE_H #define _B_EXAMPLE_H #include <cstdint> #include <cstring>  class B { private:     char* const x;     const std::uint32_t xLen;  public:     B(char* x, std::uint32_t len) : x(x), xLen(len) {}     virtual ~B() {}     void add(const char* str)     {         strncpy(this->x, str, this->xLen - 1);     } };  template<std::uint32_t T> class GenB : public B {     public:         char myBuf[T];         GenB() : B(myBuf, T) {} }; #endif   a.h  #ifndef _A_EXAMPLE_H #define _A_EXAMPLE_H #include "b.h" #include <cstdint> class A { public:     void foo(B& t); };  #endif   a.cpp  #include "a.h"  void A::foo(B& obj) {     obj.add("Top secret"); }   main.cpp  #include "a.h"  int main() {     GenB<20> bObj;     A aObj;     aObj.foo(bObj);      return 1; }


How do I use Photoshop via wine on Ubuntu 15.04?

If you have any experiences on using Photoshop via Wine then please share with me about your experience.


I have a toilet which has water condensing on the outside of the tank and then dripping down onto the floor.  No, the tank is definitely not leaking.  This is weather related, as this always happens on somewhat warmer days (i.e. > 70 F) and when we have no HVAC running (i.e. < 90 F), so our windows are open and there is some humidity in the air.   Obviously the cold water in the tank is causing the condensation to occur on the outside.  Can anyone recommend a solution to this problem, other than placing buckets behind the toilet?  How do I keep my floor from getting wet every spring and fall?


In order to solve a probability problem I had to prove the following equality:  $$\frac{1}{2^{2n+1}}\sum_{r=0}^{n}\binom{2n-r}{n}2^r=\frac 12$$  I tried to prove it but to no avail. The main problem is that I've never studied combinatorics, and our introduction to the binomial coefficient was very minimal. The only two things I know about them is their symmetry, and the binomial theorem of Newton. However, In order to use one of these properties or both, I need the summation variable $r$ to be on the bottom of the coefficient; rather than on the top of it.  Thanks!


Windows 7/Ubuntu does not boot after installation.

I installed Ubuntu on Windows 7 now neither OS boots up.  How can I recover Windows OS and uninstall Ubuntu?


Is it Possible to Disable Feed and Topics for an Object Completely at Profile Level / Page LayOuts

I need to display Case object(Detail page) in Portal Page for External users, And i need to Hide the Feed(No More "Show feed / Hide feed ") completely. Is it possible to hide feed in case object rather than creating a new page that display Case details in Portal page. i have created a new page layout with Un-checking "Feed based Layout" but i didnt achieved.Please any one clarify me,


How do you access a list in group of 3 in python?

origCodon = ([orig[i: i + groupSize] for i in range(len(orig) + 1 - groupSize)]) patCodon = ([pat[i: i + groupSize] for i in range(len(pat) + 1 - groupSize)]) print (patCodon) origCode = [] patCode = [] for p in patCodon:     for d in dna:          if d == p:               x = dna[p]               print (p)               patCode.append(x)   The code above takes two lists and splits them into groups of three, but when I go to check each individual element, it makes a new list of three, moving along one element each time.  i.e. this is one list made:  ['AAC', 'ACT', 'CTG', 'TGC', 'GCA', 'CAG', 'AGC', 'GCT', 'CTC', 'TCA']   But these are the elements it checks:  AAC ACT CTG TGC GCA CAG AGC GCT CTC TCA   How do I make it so that each group of three is checked and then it moves on to the next?  My list is split into groups of three (becoming items in the list), I want to check each of those items for their corresponding amino acid (in a dictionary), but the  program keeps making new lists, e.g. the user enters AAATTT, then the program checks:  AAA AAT ATT TTT   rather than just AAA and TTT


Error: java.lang.NoClassDefFoundError: kotlin/jvm/internal/Intrinsics [javafx]

My project is not very advanced cause I've just started programming in Java/JavaFX.  Users select country from combobox, then below in text field write a city. After pressing OK button user should receive a weather forecast for one day for the city entered. Actually names are getting correctly from inputs and sets as private fields in Weather class. I'm using weather OWM JAPIs from: . All needed libraries are added to project. (I've read that better way is to use Maven/Gradle frameworks but i'm totally green in using them).  Problem appears when method showCurrentWeather from Weather class is launched. New created object owm in line 19 causes lot of errors f.e:  Caused by: java.lang.NoClassDefFoundError: kotlin/jvm/internal/Intrinsics at net.aksingh.owmjapis.core.OWM.<init>(OWM.kt) at sample.Weather.showCurrentWeather(Weather.java:19) at sample.Controller.searchWeather(Controller.java:30)   Weather class:  public void showCurrentWeather() throws APIException {      OWM owm = new OWM(MyConstants.OWM_API_KEY);     CurrentWeather cwd = owm.currentWeatherByCityName(city);     System.out.println("City: " + cwd.getCityName());     System.out.println("Temperature: " + cwd.getMainData().getTempMax()             + "/" + cwd.getMainData().getTempMin() + "\'K"); }   Controller class  public void searchWeather() throws APIException {      String selectedCountry = comboBox1.getSelectionModel().getSelectedItem().toString();     String selectedCity = textField1.getText();     Weather weather = new Weather(selectedCity,selectedCountry);     weather.showCurrentWeather(); }   Any answer/advice is really appreciated.


Is there any alternative to grep's -A -B -C switches (to print few lines before and after )?

grep -A 2 -B 3    prints 2 lines after the grep string and prints 3 lines before.   grep -C 3   prints 3 Lines before and 3 lines after  Unfortunately, the grep I'm using does not support these options. Are there any alternative commands or script available to simulate this? Using sed/awk/perl/shell scripts?


regex for mongodb url string, javascript

I'm a bit stucked with this regex problem, I need to check if url has at start mongodb:// and at the end of a string - port with numbers :27017 and also if there is no slash / .  For example:  /myRegexForThis/.test('mongodb://testUrl:port') => true /myRegexForThis/.test('mongodb://testUrl:port/') => false /myRegexForThis/.test('mongo://testUrl') => false /myRegexForThis/.test('mongodb://testUrl:port') => false   currently I have only start part: ^(mongodb:\/\/)


Let $A$ ne an $n\times n $ upper triangular matrix with complex enries.I have to check the validity of the statement      If $A\neq I$ and if $a_{ii}=1$ $\forall i, 1\le i\le n$, then $A$ is not diagonalizable.   I wanted to know whether my proof(given below) is correct or not?Please provide the correct proof...


What is the difference between conduction of electric wave in conductor and propagation of electromagnetic wave in dielectric?  Why propagation term is used for dielectric and conduction for conductor?.  Somehow why propagation of electromagnetic wave (is it energy wave) is not possible in conductor, but in dielectrics, and conduction (power signal) not possible in dielectric.


Why the first swap attempt works, but the second doesn't work?

package main;  public class Main {     double radius;     public Main(double newRadius) {         radius = newRadius;     }       public static void main (String [] args) {         Main x = new Main(1);         Main y = new Main(2);         Main temp;         // try to swap first time         temp = x;         x = y;         y = temp;         System.out.println(x.radius + " " +  y.radius);         x = new Main(1);         y = new Main(2);        // try to swap second time         swap(x, y);        System.out.println(x.radius + " " + y.radius);     }     public static void swap(Main x, Main y) {         Main temp = x;         x = y;         y = temp;     }  }   Why the first time worked, but the second time didn't? The first one did the swap, but the second one didn't. I'm passing the reference to the function. Why this doesn't work?


How to keep footers at the bottom of the page?

This is my CSS code  footer {     position: relative;     height: 50px;     width: 100%;     background-color: white; } p.copyright {       position:absolute;     width:100%;     line-height:40px;     color:red;     vertical-align:bottom;     text-align:center;     bottom:0; }   This is my aspx HTML code
   Copyright 2017 Anime Toys
        I'm trying to keep footers at the bottom of all web pages. The problem that I'm facing is that some web pages contains small amount of content, the footer can sometimes sit halfway up the page leaving a blank space underneath.  How do I solve this issue? Can someone fix my code?


When will my device get the Android 4.0 update (Ice Cream Sandwich)?

Android 4.0 (Ice Cream Sandwich) was  on October 19, 2011.  (You can review  or the  at the official Android Developer's site.)  Of course, not all devices will get this update right away and others won't get it at all. Each manufacturer and carrier often choose to add their custom modifications which tend to delay the official release.  When will each device get Android 4.0, either officially or unofficially, if ever?  See also:


Proving $A \cong C$ if $A \cong B$ and $B\cong C$.

Question: Let $A$, $B$, $C$ be groups. Assume that $A \cong B$ and $B\cong C$. Prove that  $A \cong C$.   Proof:   Let $\phi: A \to B$ and $\sigma: B \to C$  Suppose $\sigma \circ \phi: A \to C$  $i). One-to-one:$  Then $\sigma \circ \phi$ is one-to-one. Let $a, b \in A$  Suppose $(\sigma \circ \phi)(a) = (\sigma \circ \phi)(b)$  $\Rightarrow$ $\sigma (\phi(a)) = \sigma (\phi(b))$  (Since $\sigma$ is one-to-one.)  $\Rightarrow$ $(\phi(a)) = (\phi(b))$  (Since $\phi$ is one-to-one.)   $\Rightarrow$ $a = b$  $ii). Onto:$  Then $\sigma \circ \phi$ is onto.   Let $c \in C$. Because $\sigma$ is onto there exists $b \in B$ such that $\sigma(b) = c$. Also since $\phi$ is onto there exists a $a \in A$ such that $\phi(a) = b$.  Then $\sigma(\phi(a)) = \sigma(b) = c$  Then $\sigma \circ \phi$ is onto.  $iii).Opreation  - Perserving:$  Let $x_1, x_2 \in A$.  Then $(\sigma \circ \phi) = \sigma(\phi(x_1, x_2)) = \sigma(\phi(x_1)\phi(x_2))$  Because $\phi(x_1) \in B$ and $\phi(x_2) \in B$,   $\sigma(\phi(x_1)\sigma(\phi(x_2)) = (\sigma \circ \phi)(x_1)(\sigma \circ \phi)(x_2)$  Then $\sigma \circ \phi$ is operation-preserving.   $\therefore A \cong C$  I know it isn't the most elegant proof, but I was wondering if this is totally correct or if I missed something or did something incorrectly. Any help appreciated!


Is was wondering what sequence of steps does the OS take when we trigger the remove device safely option?  Are the steps OS (in)dependent?


Finding the number of elements of order 2 in $D_{n}$

Question:   If d is a positive integer, d $\neq 2$ and d divides n, show that the number of elements of order d in $D_{n}$ is $\phi \left ( d \right )$.   How many elements of order 2 does $D_{n}$ have?      Theorem:   If d is a positive divisor of n, the number of elements of order d in a cyclic group of order n is $\left \langle d \right \rangle$.   $D_{n}$ has order 2n.  d is a positive integer and d divides n so there exists a subgroup, say $\left \langle a \right \rangle$, of order d.   Hints are appreciated. Thanks in advance.


How to sort a DataView in a case-insensitive manner?

I have a DataTable.  I'd like to sort its default view by a column name 'city'.  I'd like the sort to be case-insensitive.    Here is the code I have:  DataTable dt = GetDataFromSource(); dt.DefaultView.Sort = "city asc";  MyReport.DataSource = dt.DefaultView;   Thanks.


There are 50 light bulbs in a room each with its own switch.  Initially all light bulbs are off.  Dick follows the following procedure 50 times:  He randomly selects a light bulb and flips the switch, turning it on if it is off and off if it is on.  What is the expected number of light bulbs on in the room after 50 flips, rounded to the nearest natural number?


Electric field inside the "Dees" of a Cyclotron and why no "Cups"

I read about cyclotron and how does it work. Several references say that the particle to be accelerated is only accelerated when it is between the gaps of the "Dees" or the semicircular disc like metallic containers. These "Dees" are connected to the RF source or the Oscillator.  I don't understand why would there be no electric field inside the "Dees". I know why would any point inside a cavity in a conductor would have zero electric field due to electrostatic shielding. BUT since the "Dees" have an open cavity and not a fully enclosed cavity, shouldn't there should be some E-field inside the "Dees"? Saying that there is no field inside the "Dees" should be like saying that a hemispherical shell can only have electric field on its outer surface, right? Then why is it said so?  Also, can hemispherical shells be used instead of the "Dees" in a cyclotron? Why? or why not?


How can I mute an individual application from command line?

I can see a list of applications currently playing sound:    And I can mute them by clicking the On/Off slider.  How can I do thi from command line? I want to be able to mute google-chrome, so that I can answer my phone.  I can already play/pause spotify, but I can't use that technique for chrome, because Youtube doesn't integrate into the sound control system.


What is the proper 'per code' method for running nonmetallic sheathed cable above a ceiling in the attic?

Can the wiring be run over the top of the ceiling joist, or must it be run through bored holes when running perpendicular to the joists?   This is a non-habitable space, will have an attic entrance only for the purpose of blown-in insulation and is not tall enough to stand in. There will be no junction boxes, lights or any other reason to enter this space.


Why singlular + use instead of plural + use? (Eg. "drug use" instead of "drugs use")

This question is probably asked over and over again, but I cannot come up with keywords that can clearly describe this question to a search engine.  One of my friends has this fill-in-the-blank question on their test:     "Why has student spending become a greater concern over the last few years? Because there is a trend of ____ use."   The correct answer is "credit card use," but my friend got it wrong for using the plural form and writing down "credit cards use," and my friend is curious as to why this is wrong. I cannot remember a quantitative grammar rule that defines this other than that my language intuition tells me it is wrong. Can anyone give a quantitative explanation?


What options exist for changing usernames transparently in Webmail?

Currently, we have a fully working POP/IMAP/Webmail system (using Dovecot and Roundcube) that is a gleaming tower of perfection in its intended design. We have thousands of customers who belong to a "default" domain (I'll call it ourdomain.com), and successfully log in with a username and password. We have a few thousand more who own domains that we host, and they log in successfully with their full e-mail address and password (call it customerdomain.com). It's been this way since the 1990s, with a lot of entrenched customer configuration.  The problem is now that people are used to logging into web forms with a full e-mail address, people who use ourdomain.com have to be reminded to log into webmail using only their username. This is a call our tech support department gets several times a week (and even I am guilty of doing this, I just don't call tech support about it), and probably should be eliminated with some kind of software solution.   So how do we get either Roundcube or Dovecot to recognise "username@ourdomain.com" as "username" instead, without having to change everyone's actual username in our system? But only do that if the domain is "ourdomain.com" and not "customerdomain.com". Keep in mind that any custom coding we do will have to be re-implemented every time we do security upgrades, and we would only consider that option as the last possible choice.  TL;DR:  We need this logic:  if $email contains @ourdomain.com {     remove @ourdomain.com;     submit to roundcube; } else {     submit to roundcube; }


What is the difference between offline and ?  Is it just a matter of learning over the entire dataset (offline) vs. learning incrementally (one instance at a time)?  What are examples of algorithms used in both?


How can I know the classes of a given package

Given a package in java language, I want to know how many classes it contains and their list (list of these classes).  I can access to my package with myClass1.class.getPackage() but after this I don't have some thing like getClasses() or size() or lenght or ClassesCount().  Thank You


Proof verification of a number theory problem involving sequences.

$\textbf{Question:}$Does there exist an infinite sequence of integers $a_1, a_2, . . . $ such that $gcd(a_m, a_n) = 1 $ if and only if $|m - n| = 1$? $\textbf{My solution:}$Suppose we have a $n$ element sequence that satisfies the condition.say $a_1,\cdots,a_n$. Now take $n-1$ distinct primes that divides none of the elements of this sequence.call the primes $p_1,\cdots,p_{n-1}$ Then the sequence $a_1p_1,\cdots,a_{n-1}p_{n-1},a_n$ also satisfies the condition. Now,simply take $a_{n+1}=p_1....p_{n-1}$. Then $a_1p_1,\cdots,a_{n-1}p_{n-1},a_n,a_{n+1}$ satisfies the condition.Hence,we can always increase the size of the sequence. In addition $a,b$ with $(a,b)=1$ is a two element sequence that satisfies the condition.Hence we can form an infinite sequence that satisfies the given conditions. If there is any flaw in my argument do tell me.


How do I change the font locally for one word in Beamer? I want to type the Greek letter Phi in uppercase and lowercase. The uppercase in Beamer show  but I want to have it looks like the varPhi which is  . Is there a way (I am thinking of changing the font type) so that the Phi also looks like a straight up varPhi? Thanks in advance for any help!


Help With Infinite Redirect From .htaccess using MVC with PHP

Let me preface by saying that I'm fairly new to .htaccess authoring and have usually left the nitty gritty up to my hosting provider. I've recently decided to implement a hand rolled MVC framework in php and was using the .htaccess file to redirect using "seo" friendly urls. My MVC implementation uses the variables module, class, event, and parameter. They are specified in the url in that order, e.g. . I want it to work if you chop off any part of the url. This was all working fine until I moved my site up one level and subsequently copied my .htaccess file. Now I'm getting an infinite redirect loop with one of the rules that was working fine before I moved it.  Here is my .htaccess file:  Options +FollowSymLinks  RewriteEngine On   RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-d RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-f RewriteRule ^$ /index.php?module=default&class=home [QSA,L]  RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-d RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-f RewriteRule ^([^/]*)$ /index.php?module=$1 [QSA,L]  RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-d RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-f RewriteRule ^([^/]*)/([^/]*)/([^/]*)$ \     /index.php?module=$1&class=$2&event=$3 [QSA,L]  RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-d RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-f RewriteRule ^([^/]*)/([^/]*)/([^/]*)/([^/]*)$ \     /index.php?module=$1&class=$2&event=$3&parameter=$4 [QSA,L]   Now, if I take out the section that reads:  RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-d RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-f RewriteRule ^([^/]*)$ /index.php?module=$1 [QSA,L]   It works great. The problem is if I leave that out and someone types  I get a 404 (since that directory doesn't exist and none of the rules are matching). So why does that rule now not work and why did it work when index.php (and this .htaccess file) are in a sub-directory?


The question was initially: $$\int{\frac{1}{x^4+1}dx}$$ By trig substitution I reached the below equation and I'm stuck here: $$\int\frac{1}{2}{(\cot x)^{1/2}dx}$$ How can I proceed from here?Any simple methods are appreciated.


Let $A$ be a finely generated Abelian group. Prove that there is a topological space $X$ with a basic point $x_0$ such that $\pi_1(X,x_0)\cong A$.  I'm trying to solve this problem but I do not know where to start, here are several posts similar to this that I do not understand:     Is there an easy way to prove my proposition? Thank you very much


Why can one bend glass fibers without breaking it, whereas glasses one comes across in real life is usually solid?  Is there also a good high-school level explanation of this?


When leasing/renting out an owned property, is there a standard ratio between monthly rent and the mortgage?

I'm leaving the country for work for roughly a year, and would like to sublease my home to a friend of mine living in the area. I have no experience as a landlord, and I've had a tough time figuring out if an appropriate monthly rent can be estimated as some percentage of the monthly mortgage payment.  For ease of computation, let's say my mortgage is $1000/month on a 25 year mortgage. Are there any rules of thumb for what would be an appropriate estimate for monthly rent based on this information?


Can't download apps through the software center

I'm new to ubuntu , I'm using the latest version. I've been trying to download apps from the software center but I keep getting this error notification(below). Can anybody tell me how to fix this please.  installArchives() failed: dpkg: error processing package tzdata (--configure):  package tzdata is not ready for configuration  cannot configure (current status `half-installed') Errors were encountered while processing:  tzdata dpkg: dependency problems prevent configuration of python-tz:  python-tz depends on tzdata; however:  Package tzdata is not installed. dpkg: error processing package python-tz (--configure):  dependency problems - leaving unconfigured dpkg: dependency problems prevent configuration of python-matplotlib:


I can browse the web fine, watch YouTube, listen to music, etc. But when I try to join ANY Minecraft server, as soon as I try to make a connection, I either:  Time out my connection  or:   Sit there waiting for it to load, then disconnect  On Minecraft, it says I have good ping to the server, but then I join it and I lag out as I stated above. I can connect to other servers on other games.. but not Minecraft. I have restarted my PC and my modem, still nothing.  What can I do to solve this issue ?


Redirecting the content of a file to the command "echo"

I have a file named my_file.txt whose content is just the string Hello. How could I redirect its content to the command echo?  I know I have the commands less, cat, more... but I need to do it with echo.  I tried this:   $ cat my_file.txt | echo   and also this:  $ echo < my_file.txt   But in both cases it appears only a blank in the stdout, not the content of my_file.txt.  How could I do that?


What is the term for someone who has a last name that can also be a first name? For example, Brian Stella.


If $(ab)^k = a^k b^k$ for two consecutives integers $k$, is $G$ abelian?

Suppose $G$ is a group such that there exists $k\in\mathbb{Z}$ satisfying $(ab)^k = a^k b^k$ and $(ab)^{k+1} = a^{k+1} b^{k+1}$. Is $G$ abelian?  I've tried to use the same argument in  post, but it doesn't work. Is there a non-abelian group $G$ with this property?


What is the difference between git clone, git fetch and git pull?

Could you explain the difference between git clone, git pull and git fetch? I have read some other answers but none of them state the difference between the three clearly.


Number of roots and degree of polynomial

Let $F$ be a field, and $p \in F[X]$ let be a polynomial of degree $n.$ There exists some field extension where $p$ has $n$ roots. Do you know the proof of following statement?


Very easy question, but I'm kind of unsure, just got into Big O. If that would be just 3 loops, it just would be N^3, but there are constant loops and also a loops to n-1, which confuses a bit. How does complexity change in that case? Algorithm: for i=1 to 10      do for j=1 to n-1         do for k=1 to 8


Prove the existence of $c$ such that $f'(c) = 2c(f(c) - f(0))$

Let $f:\mathbb{R}\to\mathbb{R}$ be a differentiable function s.t. $f'$ is continuous. Suppose $f'\left(\frac{1}{2}\right)=0$, prove that there is $c\in\left(0,\frac{1}{2}\right)$ s.t.  $$f'(c)=2c(f(c)-f(0))$$


Why can't "your communities" be edited on mobile?

Using (the latest) Firefox on Android (6.0.1) there's no "edit" link to the right of "Your Communities" which is present on the full site. This may be by design, although it's not clear why having the ability to search for text and then click "add" and then "save" is deemed to be any more problematic for mobile users than desktop ones.


Can I mount 0.4x, 52mm wide angle lens convertor on Nikon's 18-55mm, Ø55 kit lens?

I want to have an option to capture wide-angle shots. Since the wide-angle lens is expensive, I want to give a try to 0.4x wide-angle converter lenses. I found one such lens here on .  QUESTION: I found that all the lens converters have a specification that they can be mounted on the lens with  filter diameter 52 mm, 58 mm and 67 mm. But I checked that my 18-55mm kit lens has a specification Ø55.      Is it possible for me to use the above mentioned wide-angle lens   converter with my kit lens?   My Camera: Nikon D5600


Postfix on Ubuntu won't send emails "No such file or directory '/etc/postfix/cacert.pem'"

I'm trying to get postfix set-up on Ubuntu 13.04 but no luck so far. I found a few answers here on ServerFault that didn't work. I re-installed a bunch of times, nothing. This is my first time dealing with it, I followed this  and . I tried , nothing. This is what I get from telnet localhost 25 and ehlo localhost:  250-elclanrs.localdomain 250-PIPELINING 250-SIZE 10240000 250-VRFY 250-ETRN 250-ENHANCEDSTATUSCODES 250-8BITMIME 250 DSN   As you can see, no AUTH in there...  This is my main.cf:  smtpd_banner = $myhostname ESMTP $mail_name (Ubuntu) biff = no  append_dot_mydomain = no  readme_directory = no myorigin = /etc/mailname mydestination = $myhostname, localhost.$mydomain, localhost mynetworks = 127.0.0.0/8 192.168.1.0/24 [::1]/128 [fe80::]/64 mailbox_size_limit = 0 recipient_delimiter = + inet_interfaces = all inet_protocols = all  relayhost = [smtp.gmail.com]:587 smtp_sasl_auth_enable = yes smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd smtp_sasl_security_options = noanonymous smtp_tls_CAfile = /etc/postfix/cacert.pem smtp_use_tls = yes   Then I've this in sasl_passwd:  [smtp.gmail.com]:587 elclanrs@gmail.com:mypass   I also configured php.ini:  sendmail_path = "/usr/sbin/sendmail -t -i"   Nothing is working, emails are not being sent from PHP. How to make it work?


What are the current options for getting from SJD airport to Cabo San Lucas and vice versa?

As of 2019, what are the options for getting to/from Cabo San Lucas from ? The options I'm aware of are:   Official taxi Uber is available, but they can't pick up passengers from the airport There are shared shuttles leaving the airport There's apparently a cheap public bus, but I couldn't locate exact details   Bonus points for sharing the easiest way to catch an Uber on the way from the airport. Perhaps one can take one stop on the public bus and then get an Uber from there?


I am playing Minecraft 1.12 but today the in-game textures look much lower quality than usual. I don't have any of the super secret settings turned on, and I'm unsure how to fix this and get the normal textures back.


As the title suggests, How can I become anonymous over the internet, i.e disallow the websites from tracking my public as well as private IP address.  Please help!


I want to install php7.4-soap on my Ubuntu 20.04 machine, so I ran sudo apt-get install php7.4-soap But I get following error: Reading package lists... Done Building dependency tree        Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies:  php7.4-soap : Depends: php7.4-common (= 7.4.3-4ubuntu1) but 7.4.5-1+ubuntu19.10.1+deb.sury.org+1 is to be installed E: Unable to correct problems, you have held broken packages.  How can I deal with this error?


Why we can know what flavor the neutrino is created but not their mass?

All neutrino knows which of the 3 flavours they must be upon their creation, however their mass becomes uncertain... why is that? isn't mass supposed to tie to which ever flavours like for example an electron neutrino has a mass of say x electron volt and tau neutrino y electron volt but clearly this is not the case. So my question is what is it that are oscillating their flavour or mass?


What part of speech is "to" when attached to an infintive?

For example, in "to see", what part of speech is "to"?


Automorphism groups of isomorphic groups are isomorphic

Say $G \cong H$ are isomorphic groups. Show $Aut(G) \cong Aut(H)$  I just made this up so I'm not sure if actually $Aut(G) \cong Aut(H)$ is true but I'm $99.9\%$ sure this should be true   I'm having trouble with the proof :'(  Let $\theta:G \rightarrow H$ be the isomorphism and $\phi\in Aut(G)$  Let $g_1,g_2\in G$ and let $h_1,h_2 \in H \ \ with \ \ h_1 = \theta(g_1) \ \ and \ \ h_2 = \theta(g_2)$  If $\phi(g_1) = g_2$  I want to show that $\exists \alpha\in Aut(H)$ such that  $\alpha(h_1) = h_2$  I tried composing $\theta$ and $\phi$ to get into $H$ but that doesn't get me anywhere. Is there something wrong with this approach?   Thanks ! :D  Wait a minute....  $\theta(\phi(g_1)) = \theta(g_2) = h_2$  $\theta(\phi(g_2)) = \theta(g_1) = h_1$  I think I see something here, $h_1$ and $h_2$ were permuted in the same way $g_1$ and $g_2$ were but $\theta \phi : G\rightarrow H$ so it cant be in $Aut(H)$


How Can I get next 6th date every time using javascript & jquery

function sixthDate() {   var curr = new Date(); // get current date   curr.setDate(curr.getDate() + 6);   return curr; } console.log(sixthDate());     It is just showing me same 6th date every time! But I want the next 6th date everytime I call ( like : 18 june 2020 + 6 = 24 june 2020 , 24 june + 6 = 30 june ).


Show that $rank(A)+rank(B) \leq n$, when $A,B$ are $2$ matrices of size $n \times n$, and $AB=0$

Question from homework in Linear Algebra:  Let $A,B$ be two matrices of size $n \times n$ such that $AB=0$.  Show that: $rank(A) + rank(B)  \le  n$ .  It probably has something to do with the dim of the null space or column space but I can't put things together from what we've learned...  Please help.. Thanks. :)


How to convert CD to mp3 using Windows 7

I have Audio CD that I want to convert to mp3 on my laptop with Windows 7.  I am ultimately trying to load onto my android phone. What is the process?  I am a computer neophyte so not able to find instructions on my laptop.


Do I need to disable Windows Fast Startup if Ubuntu is installed on a separate drive?

I have set up Ubuntu and Windows 10 as dual boots on my computer. I read in many cases that one should disable Windows Fast Startup to prevent data loss due to Windows's hibernation files. But in my case the two OSs are installed on separate hard drives.   Would I still need to disable fast boot?


How to properly convert parameters to const char *?

I got the following errors while compiling, here's the problem part of code. Please help me understand what's wrong?  for (std::vector<std::string>::iterator i = files.begin(), end = files.end(); i != end; ++i)     {        printf("%s%s\n", parm.c_str(), i->c_str());         TiXmlElement *fileElement = new TiXmlElement("File");         fileElement->SetAttribute("name", *i); // error C2664         parentElement->LinkEndChild(fileElement);     }     files.clear();       for (std::vector<std::string>::iterator i = subFolders.begin(), end = subFolders.end(); i != end; ++i)     {        printf("%s%s\n", parm.c_str(), i->c_str());         TiXmlElement *fileElement = new TiXmlElement("Folder");         folderElement->SetAttribute("name", *i); //error C2227         parentElement->LinkEndChild(folderElement);         PrintDir(parm + *i + "\\", folderElement);     }    error C2664: void TiXmlElement::SetAttribute(const char *,const char *): cannot convert parameter 2 from 'std::basic_string<_Elem,_Traits,_Ax>' to 'const char *'; error c2065 folderElement undeclared identifier; error C2227 left of '->SetAttribute' must point to class/struct/union;


how to evaluate this double integral by change the order?

$\int_{0}^\infty \frac{\cos(ax)-\cos(bx)}{x}dx$ I represented the integrand by an integral of $\sin(xy)$ to get an double integral $\int_{0}^{\infty}\int_{b}^{a} \sin(xy)dydx$ Then I want to change the order of this double integral, but I how can I solve $\int_{0}^{\infty}\sin(xy)dx$ first?


I need put log scale in colormap in tikz

I used gnuplot, but decided to use tikz now. When I need put log scale in colorbar in gnuplot  I write logscale cb. What options for tikz?  Thank you for your help.  \documentclass[tikz]{minimal} \usepackage[latin1]{inputenc} \usepackage{pgfplots} \usepackage{tikz} \usepackage{graphicx} \usepackage{graphics} \usepackage{amsmath} \pgfplotsset{compat=newest} \usepackage{tkz-kiviat} \usepackage{luamplib} \usepgfplotslibrary{colormaps} \usetikzlibrary{shapes,arrows} \usepackage{pgfplotstable} \usepackage{tikz-3dplot} \pagestyle{empty}  \begin{document} \input{u10cxz.tikz} \end{document}  \begin{tikzpicture}         \begin{axis}[         xlabel={\footnotesize $x$ [$m$]},ylabel={\footnotesize $z$[$m$]},zlabel={\footnotesize $C$ [$g/m^3$]},         width=10cm,         height=10cm,         view={120}{40},         grid=both,         colormap,         colorbar]         \addplot3 [surf,x domain=0:12,y domain=30:70, z domain=0:0.00006, samples=50] table[x index=0,y index=2,z index=4]{data/u10cxz.dat};         \end{axis}     \end{tikzpicture}


Getting null pointer exception when casting driver.get again selenium webdriver

i am running a test suite, and my test case extends the following base class:  public class BaseTestSuite {     public static final Logger log = LogManager.getLogger(C2630.class.getName());     public WebDriver driver;     public String baseURL;     public LoginPageFactory loginPage;     public DashboardPageFactory dashboardPage;     public MerchantsPageFactory merchantsPage;     public MerchantDashboardPageFactory merchantDashboard;     public PayPagesPageFactory payPage;     public LaunchPageFactory launchPage;     public HubPayPagePageFactory hubPayPage;     public TransactionCompletePageFactory transactionCompletePage;       @BeforeSuite     public void beforeSuite() {         baseURL = "myWebsite.com";         System.setProperty("webdriver.chrome.driver", "D:/Automation/chrome driver/chromedriver.exe");         driver = new ChromeDriver();         // Maximize the browser's window         driver.manage().window().maximize();         driver.manage().timeouts().implicitlyWait(20, TimeUnit.SECONDS);         loginPage = new LoginPageFactory(driver);         dashboardPage = new DashboardPageFactory(driver);         merchantsPage = new MerchantsPageFactory(driver);         merchantDashboard = new MerchantDashboardPageFactory(driver);         payPage = new PayPagesPageFactory(driver);         launchPage = new LaunchPageFactory(driver);         hubPayPage = new HubPayPagePageFactory(driver);         transactionCompletePage = new TransactionCompletePageFactory(driver);     }      @BeforeClass     public void beforeClass() {         driver.get(baseURL);     }  }   The first test case runs fine when going through Before Suite and Before Class, however when the second test case begins, i want to redirect it to the MyWebsite.com so that it begins on the homepage but i get an error when it runs that line and it skips the whole test. any ideas would help, thank you!  here is the exception  java.lang.NullPointerException     at testClasses.C2631.TestCase(C2631.java:12)     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)     at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)     at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)     at java.lang.reflect.Method.invoke(Unknown Source)     at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:108)     at org.testng.internal.Invoker.invokeMethod(Invoker.java:661)     at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:869)     at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:1193)     at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:126)     at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:109)     at org.testng.TestRunner.privateRun(TestRunner.java:744)     at org.testng.TestRunner.run(TestRunner.java:602)     at org.testng.SuiteRunner.runTest(SuiteRunner.java:380)     at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:375)     at org.testng.SuiteRunner.privateRun(SuiteRunner.java:340)     at org.testng.SuiteRunner.run(SuiteRunner.java:289)     at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)     at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:86)     at org.testng.TestNG.runSuitesSequentially(TestNG.java:1301)     at org.testng.TestNG.runSuitesLocally(TestNG.java:1226)     at org.testng.TestNG.runSuites(TestNG.java:1144)     at org.testng.TestNG.run(TestNG.java:1115)     at org.testng.remote.AbstractRemoteTestNG.run(AbstractRemoteTestNG.java:114)     at org.testng.remote.RemoteTestNG.initAndRun(RemoteTestNG.java:251)     at org.testng.remote.RemoteTestNG.main(RemoteTestNG.java:77)


I have an NVidia 1080 ti and would like to add a second.  It looks like the only thing on the NVidia site is the Founder's Edition - and they're unavailable.  So my question is:  Would a 1080 ti made by, say, EVGA give the same results as my current card if they were used together on the same render?  I understand that they'll certainly work with Blender but my concern is for the quality of the render.  I've seen tons of SO questions regarding whether multiple cards will work but I'm curious to know if there are any significant differences under the hood which would yield a poorer render than going with two identical cards.  Using Blender 2.79 + Cycles  Regarding "Marked as duplicate" designation:  This question refers specifically to the results obtained from the use of different cards.  Other questions, such as the one linked in the duplicate notice, simply address the support of multiple cards.


I want to write a C# method that can accept any number.  Something like:  public static T Sum(T a, T b) where T : number {  // (not real code)     return a + b; }   But I don't see a "number" base class in C#, as exists in most other languages I've used.  The numeric value types are IComparable, IFormattable, IConvertible, IComparable, and IEquatable, but nothing that seems to have any arithmetic capabilities.  They're all structs, with no apparent common superclass, apart from object.  (Forgive me if I'm screwing up the meaning here, since I'm not too familiar with C# structs and precisely all the ways they are like or unlike classes.)  Am I missing something, or is it not possible to write a method in C# that does "a + b" without declaring exactly what a and b are in the context of the "+"?


Appended list item not showing in page source

I've appended a list item to my gallery of thumbnail images. The thumbnail shows up on the page and everything looks good. Now I want to click on the thumbnail image and show its image in a modal. But my click event doesn't get called because, when looking at the source, the html doesn't exist. I also need to sort the items and perform certain functions when the sorting is done a certain way. Do I need to refresh or something? It works fine for the other items that already exist in the gallery.  Here is the javascript that appends a list item to the DOM.    var base64 = arrayBufferToBase64(responseText.ImageThumbnail); var thumbSrc = "data:image/gif;base64," + base64; var base64Modal = arrayBufferToBase64(responseText.Image); var imgSrcModal = "data:image/gif;base64," + base64Modal; var imageId = "pop" + responseText.YogaSpaceImageId; var imagesourceId = "imagesource" + responseText.YogaSpaceImageId;   var listItem =   "
" +   "
" +   "×" +   "" +   "" +   "" +   "
" +   "
Thumbnail label
" +   "
...
" +   "
Button Button
" +   "
" +   "
" +   "
";  var $li = $(listItem); $('ul#sortable').append($li);     This never gets called because its not in the source when I view it.    $('a.image').on("click", function () {     var imagesource = $(this).find('img:first').attr('id');     $('#modalPreview').attr('src', $('#' + imagesource).data('imagesrc'));     $('#imageModal').modal('show');  });


If $G$ has inverse of all elements, then $G$ is a group. $($ true / false$) ?$  I know a group satisfies closure property, associativity. It has a unique identity element and inverses for all elements.   I can't find any counter example to prove the statement false. If the statement is true, then how existence of inverses of all elements imply that $G$ is a group?


Force browsers to download latest versions of updated files

We have an issue, which I'm sure is commonplace, whereby after deploying our web application, some users experience problems resulting from not having the latest versions of CSS or Javascript files. As developers, we simply hit CTRL + F5 and the problems go away as our browsers download the latest version of the page and associated scripts and stylesheets. However, it's not really practical to expect our users to do this after every deployment.  I'm aware of the method of forcing browsers to download the latest versions of files by appending a query string to the references to those files, which sounds like it would work perfectly well, but I'm trying to work out how to implement this technique with the smallest overhead for our devs.  Ideally, I think what we need is some sort of automated process which can detect when changes to a .js or .css file are checked in to source control (we're using VSTS) and update any links to that file in the application. We're using  for dependency injection, so perhaps that would make things easier, but I still don't know how to implement this.  At present, the only solution I can think of is to instruct our devs, every time they modify a .js or .css file, to search the code for any references to that file and manually add a version number query string in each place. And then hope that they remember to do this.  Is there a better way?


How can I prove that $\cos(\sin x)>\sin(\cos x)$ when $0\leq x\leq \pi$

I had a midterm a few days ago,.. and my question goes like this. Prove $\cos(\sin x)>\sin(\cos x)$ where $0\leq x\leq \pi$  Also, you can use sinx>x when x>0 without proving it.  How can I prove it strictly?


When Hulk snaps the Infinity Gauntlet in Avengers: Endgame, what exactly does happen?  Do the missing people just return or does the snap set time back to five years prior?  I was confused because if it just returns the missing people, why does no one seem to age? When Peter Parker returns to school, everyone is still the same age as he was but theoretically, they should be 5 years older.  My conclusion is that the new Spider-Man movie has to be set before Avengers: Infinity War, but maybe I'm missing something.


I'm trying to draw several rectangles next to each other, and the last rectangle on the queue without the right border.  \documentclass{article} \usepackage{tikz} \usetikzlibrary{arrows,shapes,positioning} \begin{document} \begin{tikzpicture}     \tikzstyle{t1} = [rectangle, fill=white, draw=black, minimum width=0.7cm, minimum height=0.9cm, inner sep=2pt]   \tikzstyle{t2} = [rectangle, fill=white, draw=black, minimum width=1.4cm, minimum height=0.9cm, inner sep=2pt]   \tikzstyle{arrow} = [->, >=stealth', auto, thick, draw=black]   \node[t1] (q1ax) {AX};   \node[t2] (q1bx) [right=-0.1mm of q1ax] {BX};   \node[t1] (q1cx) [right=-0.1mm of q1bx] {CX};   \node[t1] (q1dx) [right=-0.1mm of q1cx] {DX};   \node[t2] (q1ex) [right=-0.1mm of q1dx] {EX};   \node[t1] (q1dots) [right=-0.1mm of q1ex] {...};   \node[t1] (q2ax) [below right=2cm and 1cm of q1bx] {AX};   \node[t2] (q2bx) [right=-0.1mm of q2ax] {BX};   \node[t1] (q2cx) [right=-0.1mm of q2bx] {CX};   \node[t1] (q2dx) [right=-0.1mm of q2cx] {DX};   \node[t2] (q2ex) [right=-0.1mm of q2dx] {EX};   \node[t1] (q2dots) [right=-0.1mm of q2ex] {..};     \draw[arrow] (q1bx.south) -- (q2cx.north);   \draw[arrow] (q1dx.south) -- (q2ax.north); \end{tikzpicture} \end{document}     Please, how can I hide the border to get this result?


Trying to make a simple deep comparison function and noticed that this block of code was returning false when it should be true. Added the console logs to find the flaw.   for(var prop in obj1){     if(obj1[prop] !== obj2[prop]){        console.log("obj1." + prop + " = " + JSON.stringify(obj1[prop]));        console.log("obj2." + prop + " = " + JSON.stringify(obj2[prop]));        return false;     } }  var obj = {here: {is: "an"}, object: 2}; console.log(deepEqual(obj, {here: 1, object: 2})); // → false console.log(deepEqual(obj, {here: {is: "an"}, object: 2})); // → true   results are   obj1.here = {"is":"an"} obj2.here = 1 false obj1.here = {"is":"an"} obj2.here = {"is":"an"} false   So I can tell the for... in prop method seems to be working because it's comparing 'here' for example. This is good. I think they're equal in the second console.log, so I think the answer is to use a different way of comparing them, because it's still evaluating them by reference possibly?


Will Ubuntu 18.04 work on i5-4210U - 1.7 GHz Dual Core?

I am currently using Ubuntu 14.04 on my laptop. I want to upgrade to 18.04 LTS but I am not quite sure if it will work.  My CPU is dual core 1.7 GHz 4th Generation i5-4210U. I upgraded my RAM from 4 GB to 16 GB. Also I am going to install Ubuntu 18.04 on SSD.  So only sort coming with respect to recommended system requirements is CPU. It was stated to have minimum of 2 GHz Dual Core processor.  My question is will it work? Should I give it a go at least?


Ubuntu 12.04.1amd64bit tls installation problem

When i finish installing Ubuntu 12.04.1amd 64bits TLS alongside with windows 8 on my laptop it was not showing ubuntu at the start-up boot but it just boot to windows 8. how do i get the ubuntu i installed?


How to convert dots to commas in mathmode?

For my study of physics I have to do various lab reports. Normally I just process all my data using python, gnuplot or Mathematica and copy it from there to my TeX document. Unfortunately all these applications use the . (dot) as a decimal seperator. Because I study in Germany the german standard says that I have to use , (comma) as the decimal seperator. In most cases the supervisors of the lab are forgiving, but one of them told me to redo my whole lab report because of this. Now I don't want to search all the 15 pages to replace all dots with commas. I could have used a  but this still implied editing the whole file.


How do people come up with difficult math Olympiad questions?

The problems that appear in difficult math competitions such as the IMO or the Putnam exam are usually very difficult and require some ingenuity to solve. They also usually don't look like they can be solved by simply knowing more advanced theory and the such.  How do people typically come up with these problems? Do they arise naturally from advanced mathematics (the somewhat infamous 'grasshopper problem' from the 2009 IMO comes to mind - to my not exactly knowledgeable mind this problem looks like it popped out of basically nowhere)? What is the perspective that mathematicians take when seemingly "inventing" these problems with no theoretical motivation to them whatsoever?


What's the command to reset a file to a specific commit?

Using git, is there a command which I can reset a file to a specific commit in the commit log?  I know git checkout file can let me reset the file to HEAD, but how to reset to a specific commit version?


How do I install Half-Life 1 and 2 on Ubuntu 12.04 if I already have the game on a Windows installer CD and on Steam. I tried it with Steam, but the game didn't launch. I also tried it on wine with the Windows installer, but it didn't work either.


My online friend is asking for money in order to visit my home country. Is this a legit request or a scam?

On Travel.SE we often see questions about a person (usually a love interest) asking for money to pay for airfare, visas, permits and other expenses. For example        What general advice can be given in such situations to the person asking the question? Is it all a scam or can there be legitimate situations in which an online friend could be asking for money?


Is it energy?  Is it energy per unit volume?  Is it energy per unit time i.e power?  What is it?


How to determine the optimal control law?

Given the differential equation $$\dot x = -2x + u$$ determine the optimal control law $u = - kx$ that minimizes the performance index $$J = \int_0^{\infty} x^2 \, \mathrm d t$$  My approach was to find the state feedback $k$. But since the value of $R$ (positive semidefinite Hermitian) is not given, that means $R=0$. How do I determine the optimal control for this system where $R=0$?


How to add page number on the .docx creating using Apache POI and java

I use some suggestion over this site but I found NullPointerException at this line:  policy.createFooter(XWPFHeaderFooterPolicy.DEFAULT, parsFooter);


I'm looking for a way to convert a route to an Url with contextual filters added. I can do it manually and it works, but I still think there should be a better, "Drupalish" way to do it.  Url::fromRoute('view.view_name.display_name')) converts to the correct base route of the view. However, there doesn't seem to be a proper way to attach filter values to that Url.  Url::fromRoute('view.view_name.display_name', ['value' => $value]) would be nice but, in the case of views, this only adds query values. It would obviously work if the route was declared in routing.yml as a normal route with parameters (if the value passed in the array corresponds to a declared parameter, it will be replaced all right) but this isn't a manually declared route but one belonging to a view page.   As I said, string manipulation on the Url works, of course. But it just doesn't feel right. Although the question is universal enough, if a use case is needed to see why this would be necessary, consider a view that shows the list of some entity and a corresponding archive block that summarizes the entities into links pointing to years or months. The block has to assemble links that point to the view the contextual filter added, eg:  /documents/listing/2020 /documents/listing/202006  where the view page itself resides at /documents/listing.


In a grid based system, where users can build their own walls to create buildings, how do you determine which parts are indoors?

I've looked around for an algorithm to solve this problem, but I can't seem to find anything.  In a game I am working on, data is held in a grid. Certain squares within that grid can be set as walls, so that the user can create buildings.  What I am wondering is how could I write an algorithm to determine which parts of the grid were indoors, that is to say, within a building, and which parts are outdoors. Thank you in advance for any advice.


If $R$ is a finite boolean then $R \cong \mathbb{Z_2} \oplus \dots \oplus \mathbb{Z_2}$

This question wants me to use a previous result, that if $e$ is a central idempotent in $R$ then $R \cong Re \oplus R(1-e)$. I was thinking about maybe some sort of induction would help here but I can't see exactly how I am going to get to the result I want.  I would like to know how to do the problem this way, because this is the way the book recommends. However, I also have heard that this problem can be done another way, by realizing that $R$ is a vector space over $Z_2$ and there has a finite basis, and i am under the impression that the result is not far away knowing this, but I can't quite connect the dots.  If somebody could guide me along these two different routes of solving this problem I would really appreciate it! Thanks!


Issue to Convert Number value To Words in PHP

I am using a function to covert number value in words. that is working fine but have a bug in some values like 33,030. this display as (Thirty Three Thousand Three) But should be (Thirty Three Thousand Thirty). But same function do correct like this value 2,778 this show correct (Two Thousand Seven Hundred Seventy Eight) function is as below.        function convertNumberToWord($num){         $decones = array(          '01' => "One",          '02' => "Two",          '03' => "Three",          '04' => "Four",          '05' => "Five",          '06' => "Six",          '07' => "Seven",          '08' => "Eight",          '09' => "Nine",          10 => "Ten",          11 => "Eleven",          12 => "Twelve",          13 => "Thirteen",          14 => "Fourteen",          15 => "Fifteen",          16 => "Sixteen",          17 => "Seventeen",          18 => "Eighteen",          19 => "Nineteen"          );      $ones = array(          0 => " ",         1 => "One",              2 => "Two",          3 => "Three",          4 => "Four",          5 => "Five",          6 => "Six",          7 => "Seven",          8 => "Eight",          9 => "Nine",          10 => "Ten",          11 => "Eleven",          12 => "Twelve",          13 => "Thirteen",          14 => "Fourteen",          15 => "Fifteen",          16 => "Sixteen",          17 => "Seventeen",          18 => "Eighteen",          19 => "Nineteen"          );      $tens = array(          0 => "",         2 => "Twenty",          3 => "Thirty",          4 => "Forty",          5 => "Fifty",          6 => "Sixty",          7 => "Seventy",          8 => "Eighty",          9 => "Ninety"          );       $hundreds = array(          "Hundred",          "Thousand",          "Million",          "Billion",          "Trillion",          "Quadrillion"          ); //limit t quadrillion       $num = number_format($num,2,".",",");       $num_arr = explode(".",$num);       $wholenum = $num_arr[0];       $decnum = $num_arr[1];       $whole_arr = array_reverse(explode(",",$wholenum));       krsort($whole_arr);       $rettxt = "";     foreach($whole_arr as $key => $i){       if($i < 20){      $rettxt .= $ones[$i];     }   elseif($i < 100){      $rettxt .= $tens[substr($i,0,1)];      $rettxt .= " ".$ones[substr($i,1,1)];    }   else{      $rettxt .= $ones[substr($i,0,1)]." ".$hundreds[0];      $rettxt .= " ".$tens[substr($i,1,1)];      $rettxt .= " ".$ones[substr($i,2,1)];      }    if($key > 0){      $rettxt .= " ".$hundreds[$key]." ";    }     }   $rettxt = $rettxt." (SAR)";   if($decnum > 0){    $rettxt .= " and ";  if($decnum < 20){      $rettxt .= $decones[$decnum];     } elseif($decnum < 100){      $rettxt .= $tens[substr($decnum,0,1)];      $rettxt .= " ".$ones[substr($decnum,1,1)].' Halalal ';   }  $rettxt = $rettxt;     }   return $rettxt; }   Help please


I have a sed command that removes comments in a file as,  sed -i /^#/d /path/to/file   This works but not when the comments are indented/have a preceding space.  like  #this is a good comment           ---- works     #this is an indented comment  ---- doesn't work   How can i change it to remove lines that has # as the first visible character?


Difference between $\triangleq$, $:=$, $=$ and $\equiv$ when defining a function

Which of the following notation is a correct definition of the square function?   $f(x) \triangleq x^2$ $f(x) := x^2$ $f(x) = x^2$ $f(x) \equiv x^2$   While this question is similar to , the aforementioned question and its answers do not address the usage if these symbols in the context of function definition.


Suppose there is an assassin at each end of the train, and they each use their own laser guns to assassinate a passenger $A$ located in the center of the train. At the same time, $A$ will die, otherwise $A$ will survive.  They fired on $A$ at the same time, and Observer $A$ on the train saw himself dead.  However, due to the movement of the train, the observer $B$ on the platform saw that $A$ was not dead because the laser gun did not hit $A$ at the same time.  So is $A$ dead or not?    There are three points on the platform, $A1$, $B$ and $A2$. The distance between $A1$ and $A2$ is $H$, and the distance between $A1$ and $B$ is $H / 2$.  On the train, the distance between assassins is $H$, and the distance between $A$ and any assassin is $H / 2$. The train is moving. When one assassin reaches $A1$, the other assassin reaches $A2$. Two assassins fired at the same time, and $A$ died. On the platform, $B$ saw that two assassins fired at points $A1$ and $A2$, so $B$ thought $A$ would die. But according to Einstein's theory, $A$ won't die because two assassins didn't fire at $A1$ and $A2$ at the same time. So is $A$ dead or not?


Java - Putting an arraylist in a textfile line by line

I am trying to extract specific data from a text file and obtain the first and second line from that second line.  I appended the textfile into an arraylist and I'm trying to find the specific data's index and add +1 to find the values I want.  I then alter those values.   When I try to write the values back into the textfile I keep getting "Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException".   This is my code.  public class AppendsScore extends quiz{     public void AppendsScore() {          String filename = "Data_CS";          FileWriter fw = null;          try {          fw = new FileWriter(filename, true);     }          catch (IOException e1) {         // TODO Auto-generated catch block             e1.printStackTrace();     }         List<String> Score = new ArrayList<String>();         Integer CorrectAnswers = quiz_questions.CorrectAnswers;         {          try (BufferedReader br = new BufferedReader(new FileReader(filename))){             String line=br.readLine();             //System.out.printf(FName + SName);             while (line != null) {                 Score.add(line);                 line=br.readLine();                 System.out.print(Score);             }             int name = Score.indexOf(FName + " " + SName);             int correct = 1 + name;             int NoofQuestions = 2 + name;             Integer CorrectInt = Integer.parseInt(Score.get(correct));             CorrectInt = CorrectInt + CorrectAnswers;             String CorrectStr = Integer.toString(CorrectInt); //To String from Double             Integer NoQuestionsInt = Integer.parseInt(Score.get(NoofQuestions));             NoQuestionsInt = NoQuestionsInt + CorrectAnswers;             String NoQuestionsStr = Integer.toString(NoQuestionsInt);             Score.set(correct , CorrectStr );             Score.set(NoofQuestions , NoQuestionsStr );             for(String str: Score) {                   fw.write(str);                 }             fw.close();         }             catch (FileNotFoundException e) {                 // TODO Auto-generated catch block                 e.printStackTrace();             } catch (IOException e) {                 // TODO Auto-generated catch block                 e.printStackTrace();             }      }    }   }


Where are windows command prompt customized colors stored?

I like to customize each of the 16 colors in my windows command prompt, but setting them up manually is a slow and painful process (due to some bugs in the colors tab of Console Windows Properties). I'd like a way to import these settings quickly when I am setting up a new machine.    My question is - where are these settings actually stored? In the registry somewhere? In a config file?


How to do connect to ubuntu machine (remote desktop) from windows machine remotely?

How to do connect to Ubuntu machine (remote desktop) from windows machine remotely? I need to add an account on my Ubuntu machine. Maybe through ssh?  Thanks


I just came to know that AlertDialog.Builder is a class in Android.BUt according to naming conventions java class cannot have "." operator.So, I was just confused ....can anyone help me out?


Determine average rate of change of function

How to determine the average rate of change of $f(x)= x^5-3x^4$ on the interval $[-2,4]$


Is there a printable version of a reference manual for all TeX primitives?

Everywhere in the TeX community, I see suggestions like \parskip, \obeylines, \parindent, etc. I'd be surprised not to find them even in the most basic LaTeX packages. So I figured they must be deeper down in the TeX core as primitives. Knowing how they work would be very useful.  Googling for tex primitives takes me to . Is there a printable PDF version of such a reference?


Replacing bathroom light fixture, no junction box

First time homeowner and newbie DIY-er here. I'm replacing the light fixture in our bathroom and there's no junction box behind the wall, but I think I'm seeing insulation in there too. There's a stud directly to the left of the circular hole (where the previous fixture had two screws into the stud, and two screws into the drywall). Do I need to put a junction box in there?  It seems unsafe not to.


Random effect equal to 0 in generalized linear mixed model

Sorry if I'm missing something very obvious here but I am new to mixed effect modelling.   I am trying to model a binomial presence/absence response as a function of percentages of habitat within the surrounding area. My fixed effect is the percentage of the habitat and my random effect is the site (I mapped 3 different farm sites).   glmmsetaside <- glmer(treat~setas+(1|farm),        family=binomial,data=territory)   When verbose=TRUE:  0:     101.32427: 0.333333 -0.0485387 0.138083  1:     99.797113: 0.000000 -0.0531503 0.148455   2:     99.797093: 0.000000 -0.0520462 0.148285   3:     99.797079: 0.000000 -0.0522062 0.147179   4:     99.797051: 7.27111e-007 -0.0508770 0.145384   5:     99.797012: 1.45988e-006 -0.0495767 0.141109   6:     99.797006: 0.000000 -0.0481233 0.136883   7:     99.797005: 0.000000 -0.0485380 0.138081   8:     99.797005: 0.000000 -0.0485387 0.138083     My output is this:  Generalized linear mixed model fit by the Laplace approximation  Formula: treat ~ setasidetrans + (1 | farm)   AIC   BIC logLik deviance 105.8 112.6  -49.9     99.8 Random effects:  Groups Name        Variance Std.Dev. farm   (Intercept)  0        0   Number of obs: 72, groups: farm, 3  Fixed effects: Estimate Std. Error z value Pr(>|z|) (Intercept)   -0.04854    0.44848  -0.108    0.914 setasidetrans  0.13800    1.08539   0.127    0.899  Correlation of Fixed Effects:             (Intr) setasidtrns -0.851   I basically do not understand why my random effect is 0? Is it because the random effect only has 3 levels? I don't see why this would be the case. I have tried it with lots of different models and it always comes out as 0.  It cant be because the random effect doesn't explain any of the variation because I know the habitats are different in the different farms.  Here is an example set of data using dput:  list(territory = c(1, 7, 8, 9, 10, 11, 12, 13, 14, 2, 3, 4, 5,  6, 15, 21, 22, 23, 24, 25, 26, 27, 28, 16, 17, 18, 19, 20, 29,  33, 34, 35, 36, 37, 38, 39, 40, 30, 31, 32, 41, 45, 46, 47, 48,  49, 50, 51, 52, 42, 43, 44, 53, 55, 56, 57, 58, 59, 60, 61, 62,  54, 63, 65, 66, 67, 68, 69, 70, 71, 72, 64), treat = c(1, 1,  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0,  0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0,  0, 0, 0, 0, 0, 0, 0), farm = c(1, 1, 1, 1, 1, 1, 1, 1, 1, 1,  1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2,  2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,  3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3),  built = c(5.202332763, 1.445026852, 2.613422283, 2.261705833,  2.168842186, 1.267473928, 0, 0, 0, 9.362387965, 17.55433115,  4.58020626, 4.739300829, 8.638442377, 0, 1.220760647, 7.979990338,  13.30789514, 0, 8.685544976, 3.71617163, 0, 0, 6.802926951,  8.925512803, 8.834006678, 4.687723044, 9.878232478, 8.097800267,  0, 0, 0, 0, 5.639651095, 9.381654651, 8.801754791, 5.692392532,  3.865304919, 4.493438554, 4.826277798, 3.650995554, 8.20818417,  0, 8.169597157, 8.62030666, 8.159474015, 8.608979238, 0,  8.588288678, 7.185700856, 0, 0, 3.089524893, 3.840381223,  31.98103158, 5.735501995, 5.297691011, 5.17141191, 6.007539933,  2.703345394, 4.298077606, 1.469986793, 0, 4.258511595, 0,  21.07029581, 6.737664009, 14.36176373, 3.056631919, 0, 32.49289428,  0)   It goes on with around 10 more columns for different types of habitat (like built, setaside is one of them) with percentages in it.


Evaluate the integral $\int_{-\frac{\pi}{4}}^{\frac{\pi}{4}} (\cos(t)+\sqrt{1+t^2} \cos^3(t)\sin^3(t) )dt$

Found this problem on the most recent GRE practice booklet by ets. I ended up skipping it because it looked like too much work. Going back through, I still don't know how to evaluate it.   To me, this is the obvious first step to make.  $\int_{-\frac{\pi}{4}}^{\frac{\pi}{4}} \cos(t)+\sqrt{1+t^2} \cos^3(t)\sin^3(t) dt \\ =\int_{-\frac{\pi}{4}}^{\frac{\pi}{4}} \cos(t) dt +\int_{-\frac{\pi}{4}}^{\frac{\pi}{4}} \sqrt{1+t^2} \cos^3(t)\sin^3(t) dt \\ =\sqrt{2}+\int_{-\frac{\pi}{4}}^{\frac{\pi}{4}} \sqrt{1+t^2} \cos^3(t)\sin^3(t) dt $  Having taken a few practice test, I have a gut feeling that the integral that remains will vanish, especially since the integral is over $[-\frac{\pi}{4},\frac{\pi}{4}]$, however I'm not sure how to show that this is indeed true. Is there an easy/quick way to reason through this?


Is $a \mapsto [a \cdot id]: A \to H_n(\Delta^n, \partial \Delta^n;A)$ an isomorphism?

I am hoping for a problem I am working on that the function defined above is an isomorphism of groups, but I cannot manage to prove it. Is $[a \cdot \sigma] = [a \cdot id: \Delta^n \to \Delta^n]$ for any $\sigma: \Delta^n \to \Delta^n$?


So my brother and I are connected to the same network, my brother has hosted a LAN world that my dad can connect to but my computer cannot, he has a mac and I have a windows 8 laptop. I have tried disabling windows firewall completely as well as enabling both private and public connections to Java through windows firewall. I have tried using direct connect, both by entering the ipv4:port of LAN as well as just the port. We are all running minecraft 1.9. Help me please because I am dying inside.


i have seen some analogies of spin using playing cards but i am struggling to grasp the concept due to this making no sense in terms of playing cards


How to fix "libpng12.so.0: cannot open shared object file: No such file or directory"?

I'm just starting out with Lubuntu and I've just installed DaVinci Resolve to do my video editing on.  But when I click its icon on the desktop, the loading symbol comes up and stops. When I run it in the console I get this error message:     error while loading shared libraries: libpng12.so.0: cannot open shared object file: No such file or directory   This is a bit beyond me. Any help?


I recently installed MySQL 5 on Windows 2003 and tried configuring an instance. Everything worked fine until I got to "Applying Security settings", at which point it gave me the above error (Can't connect to MySQL server on 'localhost' (10061)).  I do have a port 3306 exception in my firewall for 'MySQL Server'.


Error running Arc Hydro tools function in ArcMap?

I am trying to run a function from  in ArcMap 10.1; Sink evaluation. But before it can finish it returns an error message, that, frankly, I don't understand at all.  It goes System.runtime.interopservices.comexception (0x80004005): error hresult e_fail .  Can anyone help me solve this? I have tried all I can think of. Run the function from the toolbox instead of dropdown menus, shorten paths, restart ArcMap, reinstall AHT, open new map documents, restart my computer, wait till next day and see if it automagically have fixed itself...   After searching this forum I found a , although it's got no answers. Now I'm all out of ideas, can anyone please help me?!    I'm using ArcMap 10.1 SP1 basic license and Windows 7.    I think I have narrowed it down a bit, still not clear what's wrong though. Sink evaluation uses a series of functions in Arcmap, of which one is Zonal statistics as table. That's the one it gets stuck on. The input raster somehow does not exist, path unknown. I guess this is some intermediary raster.       After consulting the Arc Hydro team, I got the advice not to use grids stored in a gdb (which I didn't). I have also tried to change target locations, thanks to @G.Oxsen. Unfortunately neither of those solved the issue. According to the Arc Hydro team, GPL0 that I asked about earlier is an in-memory grid, so probably no problem there.   I am currently pursuing that it is related to the installation of SP1. Anyone out there using AHT with SP1 and got Sink evaluation working?    Uninstalling SP1 did not change anything, unfortunately. Still working on this, but with less intensity. Seems like I'll have to find workarounds...    By reducing the number of sinks in need of processing I managed to get Sink evaluation running. Having the files not stored in a gdb seem to help as well, as mentioned earlier, and using integer grids.  Changing the "Maximum number of unique values to render" in ArcMap Options (Customize menu), tab Raster --> Raster dataset is another tip that I got (from the Arc Hydro Team). Restarting ArcMap after running every one or two functions also helps keeping things stable.


Let $A$ be a $m$ x $n$ matrix where $A^TA$ is non-singular.  Let $C$ = $ {\{Ax|x \in \mathbb{R}^n\}}$  How do we show that the projection of any $ y \in \mathbb{R}^m $  onto $C$ is $Ax^*$ where $x^*$ = $(A^TA)^{-1}A^Ty$


Chinese Tourist Visa was stamped on observation page?

I just picked up my passport today at the Chinese Consulate, and realized my visa was stamped on one of the three observation pages on my passport after I came home. I'm not sure whether I need to get a new passport and ask them to reissue the visa. Has anyone experienced this situation before?


I want to redirect a main domain to a subdomain for example www.abc.com to xyz.test.com. Whenever i type www.abc.com it should be redirect to xyz.test.com. Both domain are hosted on same server.  Subdomain xyz.test.com is not a virtual host of web server (i.e. apache & nginx) it is code generated website and you can directly access it via . I'm using apache and nginx both so whatever best fit i will use. Any help would be appreciated.  Thank You :)


Today while I am driving my car this question came to my mind but I cannot figure it out. Sorry I am not in physics related major that this question is not expressed professionally. When you drive a real car you gets less acceleration while at higher speed. But let's say there an engine that get thrust by pushing small particles to a very high speed (near light speed). This engine should get a constant magnitude of force. (Think it as a person throwing a ball, no matter if the person is stationary of riding a car, the person should receive the same magnitude of force). Since the particles' mass is so small so the engine itself should get a constant acceleration no matter what the speed of the engine is. Say the engine is stationary and use 1 second to accelerate to 10m/s. Then it should use another second to go to 20m/s. But in the second second the engine get's three times more kinetic energy than the first second. This doesn't seem to make sense to me. How can any engine's power rate depend on it's speed? I don't think such photon engine or plasma engine exist right now. But if they come to live one day will it provide a constant thrust?


How can I align the content in the list of figures? When I use \listoffigures, some characters are overlapped.


fontawesome package not working with xelatex

Consider the following minimal example:  % !TEX program = xelatex \documentclass{article}  \usepackage{fontawesome}  \begin{document} \faTwitter{} Some Text \faLinkedin \end{document}   On my MacTeX 2016 basic system (up to date), the icons are missing in the PDF and I get the following error message:  !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! ! /usr/local/texlive/2016basic/texmf-dist/tex/latex/fontawesome/fontawesome.sty:45: fontspec error: "font-not-found" !  ! The font "FontAwesome" cannot be found. !  ! See the fontspec documentation for further information. !  ! For immediate help type H <return>. !...............................................   The example does work when I change the engine to  % !TEX program = latex   or  % !TEX program = luatex   I don't have the font installed on my system because according to the documentation the package should use the font bundled with the package (which obviously works with latex and luatex, but not with xelatex).


I get the below exception in action class when I try to submit a HTML form having file :  java.lang.NoSuchMethodError: org.apache.commons.io.IOUtils.readFully&#40;Ljava/io/InputStream&#59;[B&#41;V     at org.apache.commons.fileupload.disk.DiskFileItem.get(DiskFileItem.java:315)     at org.apache.commons.fileupload.disk.DiskFileItem.getString(DiskFileItem.java:339)     at org.apache.struts2.dispatcher.multipart.JakartaMultiPartRequest.processNormalFormField(JakartaMultiPartRequest.java:177)     at org.apache.struts2.dispatcher.multipart.JakartaMultiPartRequest.processUpload(JakartaMultiPartRequest.java:132)     at org.apache.struts2.dispatcher.multipart.JakartaMultiPartRequest.parse(JakartaMultiPartRequest.java:92)     at org.apache.struts2.dispatcher.multipart.MultiPartRequestWrapper.<init>(MultiPartRequestWrapper.java:84)     at org.apache.struts2.dispatcher.Dispatcher.wrapRequest(Dispatcher.java:838)     at org.apache.struts2.dispatcher.ng.PrepareOperations.wrapRequest(PrepareOperations.java:137)     at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:91)     at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:79)     at org.displaytag.filter.ResponseOverrideFilter.doFilter(ResponseOverrideFilter.java:125)     at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:79)     at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.wrapRun(WebAppServletContext.java:3431)     at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3397)     at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)     at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:120)     at weblogic.servlet.provider.WlsSubjectHandle.run(WlsSubjectHandle.java:57)     at weblogic.servlet.internal.WebAppServletContext.doSecuredExecute(WebAppServletContext.java:2280)     at weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:2196)     at weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:2174)     at weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1621)     at weblogic.servlet.provider.ContainerSupportProviderImpl$WlsRequestExecutor.run(ContainerSupportProviderImpl.java:256)     at weblogic.work.ExecuteThread.execute(ExecuteThread.java:311)     at weblogic.work.ExecuteThread.run(ExecuteThread.java:263)   I am using Struts 2 framework for back end and Weblogic 12c as application server.  The war deployed to server contains commons-io-2.2.jar.  What is causing this issue even when the required jar - commons-io-2.2.jar exists in the war deployed to Web logic 12c server? Is there any jar in Web logic 12c server that is conflicting with commons-io-2.2.jar bundled in the application war?  I am getting this issue after patch - 23744018 was added to Web logic 12c server.


Consider you have been given that     $$\sum_{i = 1}^{\infty}i = -\dfrac{1}{12} $$   How do you solve this sigma notation? I've not seen this kinda sigma notation before.   Regards!


Hello,  There was a question on SO() where the author linked us to his  of SO.  What is going to be done about that,is SO licensed?


I was playing minecraft and noticed that I couldn't break blocks with tools or my fist. I check to make sure I'm in survival mode and that cheats were enabled.


I need to capture screenshots of the terminal where the typed commands visually "stand out" from the rest. Right now I'm using this to make my typed commands "red":  PS1='\[\e[0;31m\]\u\[\e[m\] \[\e[1;34m\]\w\[\e[m\] \[\e[0;34m\]\$ \[\e[m\]\[\e[0;31m\]'   The problem is: everything after the prompt is red, not only my typed text    How can I fix this?  I'm using bash (CentOS 7).


I know about Daily Vote Limit, I thought it was 40 iff your question-upvotes to answer-upvotes ratio is high I've been on MathSE since this morning (I'm in India).  You need to take a look at this image.     Why is my vote count 41 ?


Where can I find a complete list of all Ubuntu releases and life terms?

I am running Lubuntu and it does not have LTS releases, so I want to know if my version is EOL or not and what versions are.   I know of the  on the wiki, but that only covers Ubuntu, not any of the distros of Ubuntu, such as Lubuntu, Xubuntu, Kubuntu, etc. I also know of the ubuntu-release-status command, and that is useful, but could be a bit confusing for new users and isn't easy to understand.  Are there any pages that has a list of all the distros and their life terms, or a page per-distro separate from the Ubuntu wiki page?


Migrating old SO questions to Programmers

I've found a fair number of old questions that obviously now belong on Programmers. However, simply voting to close doesn't seem to be doing the trick. Because they are old, no one is looking, and the vote just expires.  Is there a better way to handle these?


How could spectators watch the Tri-Wizard events?

If you're a contestant, away you go and do your things - good luck. But what could the students of Hogwarts watch? The first task seems ace - dragons and brooms, but task two happens under a lake, and task three is in a maze.  I wonder if somehow the students could see the action on a screen (a magic screen) but then the chapter after the lake we hear that everyone's hassling Harry and trying to find out what went on, because for them it was just an hour of lake.   What do you think? Do they do something in the films to imply what the audience gets to see?


How do I prove that the sum of a rational and irrational number is irrational?

How do I prove that the following proposition is true?  The sum of any rational number and any irrational number is irrational.  I am currently a beginner at discrete math and I am still getting used to the format of writing proofs.


I am working on a paper using the IEEEtran template in LyX.  I have run into a problem: While the contents (in this case, a table) of the figure float are centered, the caption is aligned to the left (see screenshot below). How can I center the caption as well?    This is generated by the following LyX document:    What I've tried:   Center the table (the table is centered) Center all the contents in the float (only the table is centered) Select the caption and center it (no effect)   Technical details:   LyX 2.0.5.1 Mac OS X 10.7.5 (Lion) All centering was performed by Right Click>Paragraph Settings>Align: Center


How does 3G/Mobile phones get allocated an IP address? Does this mess with Google Analytics?

This question is in two parts.  Q1.  How does a mobile phone get an IP address over 3G? Like, would it get the same IP for a shortish period of time (Eg. 1 day, etc)? Because my phone is constantly going in and out of buildings and underground car parks, i'm jumping between cell hotspots/receiver towers, so would I be getting a new IP each and every time? I feel like this is back to the old modem days -> every time i 'ring in/jump onto the interwebs' I get allocated a new number.  Or does it have some mac address and the Telco's mobile phone DHCP server keeps reusing the last IP based on the mac, for a specific perioud of time (eg. TTL for an IP, like a normal DHCP which has an expiry setting for the allocated IP).  Q2.   If the previous answer is that mobile's keep getting different IP's, does this mess with google analytics and the unique visitor's value? So if i'm getting 5 IP's for a day on my mobile, would that mean i'm 5 unique visitor's for the website i'm tracking?


Construct a smallest possible relation on the set {a, b, c, d} that is  irreflexive, symmetric, and transitive. I thought that the relation would be an empty set, R is symmetric because (a,b) can never belong to it and so the conditional statement is always true. R is transitive because (a,b) and (b,c) can never belong to it and so the conditional statement is always true. do you think that there is anything wrong with my assumption?


Countries with no visa requirements on its visitors

Recently I learnt that  has  to its visitors (citizens of any country) and free to enter if they hold a passport or EU national identity card.   Are there any other country(ies) which have similar no visa restrictions for its visitors irrespective of citizenship?   PS: Though Andorra has not restrictions, one needs to have a multiple-entry Schengen visa, as it's a land-locked country and only be accessed via Spain or France.


bash script not running in nohup but working fine as stand alone

I have one shell script which is using a config file. I added the following code to use config file.  source abc.config   When I ran this shell script manually it is working fine. However, when I make this shell script as a background process using no hup, it gives me following error.     line 19: source: abc.config: file not found   I debugged the shell script using   bash -x shell_script.sh   In debugging it is taking config values properly and shell script worked.  This shell script was running fine a few days ago, but suddenly it started to give errors like this. Also the same script is running fine on another environment.  To run this shell script properly we have to give the full path of config file in source statement. But that is not correct way, since config file and shell scripts both are in same folder and for source syntax we have to give config file name only.  How can I fix this issue?  P.S : Currently, I have added path of config file as follows  source ${path}/abc.config   But I want to source a config file without path of it.


In Kim experiment  I take out all the beam splitters, mirrors, and detectors for idler photons. But I leave idler photons travel freely in the universe. I look in D0 after I detect the last signal photon and I detect formless blob. I do not detect interference pattern even though I have no "which path" information just because In Principle "which path" information is incorporated in idler photons that travel and can be obtained any time in the future if one decides to.   So, I look at D0 and definitely I SEE formless blob.  Now, a year later I decide to put in only mirrors and detectors for IDLER photons(no beam splitters) that will provide me with "which path" information for every idler photon. After I detect the last idler photon I decide to look at D0 again. Will I see only two fringes on D0? If yes, does it mean that I have changed the past( the formless blob)? If No, does it mean that just because I looked at D0 a year ago and saw formless blob I will see a formless blob again(I cannot change the past)? What if I have not looked at D0 a year ago...will I see two fringes now?


Specific mixed feature between offset, buffer and intersection

I'm trying to reproduce the steps needed to aim this goal: Given a layer of polygons, I'm want to retrieve for each polygon which is at a distance less than 50m to a 2nd polygonal layer the only 5m band in the polygon facing the items of the second layer. Quite complicated explanations...I know....so, a drawing is a better way to explain myself. I want to build the red parts (the 5m band of the orange layer polygons facing the green ones, when they're at a distance less than 50m)....How would you do that with QGIS?


Chat window scrolls up and down on new messages in Google Chrome Canary

The answers of the, as duplicate, linked questions haven't helped me first. Looking at the linked  The accepted Answer says  The issue is you're using the Screenshot Capture extension by Google. Uninstall it and try an alternative (such as this).  However. I have no such extension installed. In the JavaScript Chatroom, i was   That happens in chrome 30+  Though testing it with different versions (stable, beta, canary), seems to reduce the problem to the canaray version.  I figured it is jQuery.fn.animate which is causing the trouble.  It is being called somewhere in the jQuery.fn.scrollTo function which gets redefined in  function h(a) {     i.animate(l, d, f.easing, a && function() {       a.call(this, c, f)    }) }  So to fix it temporarily it seems to be enough passing 0as duration function h(a) {     i.animate(l, 0, f.easing, a && function() {       a.call(this, c, f)    }) }  Calling the first IIFE of master-chat.js with the workaround, via a bookmarklet javascript:(function(e){function t(e){return"object"==typeof e?e:{top:e,left:e}}var n=e.scrollTo=function(t,n,r){e(window).scrollTo(t,n,r)};n.defaults={axis:"xy",duration:1.3<=parseFloat(e.fn.jquery)?0:1};n.window=function(){return e(window)._scrollable()};e.fn._scrollable=function(){return this.map(function(){if(this.nodeName&&-1==e.inArray(this.nodeName.toLowerCase(),["iframe","#document","html","body"]))return this;var t=(this.contentWindow||this).document||this.ownerDocument||this;return e.browser.safari||"BackCompat"==t.compatMode?t.body:t.documentElement})};e.fn.scrollTo=function(r,i,s){"object"==typeof i&&(s=i,i=0);"function"==typeof s&&(s={onAfter:s});"max"==r&&(r=9e9);s=e.extend({},n.defaults,s);i=i||s.speed||s.duration;s.queue=s.queue&&1<s.axis.length;s.queue&&(i/=2);s.offset=t(s.offset);s.over=t(s.over);return this._scrollable().each(function(){function o(e){l.animate(v,0,s.easing,e&&function(){e.call(this,r,s)})}var u=this,l=e(u),h=r,p,v={},m=l.is("html,body");switch(typeof h){case"number":case"string":if(/^([+-]=)?\d+(\.\d+)?(px|%)?$/.test(h)){h=t(h);break}h=e(h,this);case"object":if(h.is||h.style)p=(h=e(h)).offset()}e.each(s.axis.split(""),function(e,t){var r="x"==t?"Left":"Top",i=r.toLowerCase(),a="scroll"+r,c=u[a],d=n.max(u,t);p?(v[a]=p[i]+(m?0:c-l.offset()[i]),s.margin&&(v[a]-=parseInt(h.css("margin"+r))||0,v[a]-=parseInt(h.css("border"+r+"Width"))||0),v[a]+=s.offset[i]||0,s.over[i]&&(v[a]+=h["x"==t?"width":"height"]()*s.over[i])):(r=h[i],v[a]=r.slice&&"%"==r.slice(-1)?parseFloat(r)/100*d:r);/^\d+$/.test(v[a])&&(v[a]=0>=v[a]?0:Math.min(v[a],d));!e&&s.queue&&(c!=v[a]&&o(s.onAfterFirst),delete v[a])});o(s.onAfter)}).end()};n.max=function(t,n){var r="x"==n?"Width":"Height",i="scroll"+r;if(!e(t).is("html,body"))return t[i]-e(t)[r.toLowerCase()]();var r="client"+r,s=t.ownerDocument.documentElement,o=t.ownerDocument.body;return Math.max(s[i],o[i])-Math.min(s[r],o[r])}})(jQuery)  isn't the optimal way to get around this though. Since the canary version is not supported, this is probably not going to be fixed, so if anyones' using it and experience the problem, you can use the above code, either as bookmarklet or userscript, to temporarily get rid of the problem. It seems the question can be closed then


Programming to an interface. How to decide where its needed?

I understand that programming to interfaces helps with loose coupling. However, is there a guideline that explains when its most effective?  For example, I have a simple web application that collects data on employees, their training plans, expenses and computes their expense for the year etc. This is a fairly simple application and I can of course use an interface but wonder if there would be any use. I will be using it for the sake of using it.  It can always be argued that as the application grows in complexity and I pass around objects it would make more sense to pass the type (interface) than an implementation. So, should I wait for the application to become complex or use it right away? I'm wondering the best practice might turn out to be "this guy is over doing things".


How to Recover Lost Website/ blog data with no backup?

Unfortunately, our hosting provider experienced 100% data loss, so I've lost all content for my hosted blog website:  www.financewalk.com   Yes, I know I should have done complete offsite backups. Unfortunately, all my backups were on the server itself.   Can you please mention any solution/ tools that will help me recover my lost data?  Thanks, Avadhut


How do I redirect subdomains to a different port on the same server?

I have some subdomains I want to redirect to specific ports on the same server. Say I have  dev.mydomain.com    I want dev.mydomain.com to transparently redirect to mydomain.com:8080 and I want to preserve the original sub-domain name the url of the browser.  How do I do this with Apache 2.2? I have Apache 2.2 running on default port 80. I can't figure out the write configuration to get this to happen.  I have already set up dev.mydomain.com to resolve in DNS to mydomain.com.     This is for an intranet development server that has a non-routable ip   address so I am not so concerned about exploits and security that   would compromise a publicly facing server.


I am using a Lenovo Legion Y720 laptop with a discrete GTX 1060 GPU. I can connect to an external monitor but there is no option to chose HDMI as output source for the speakers. Only the internal speakers are listed. I tried with a laptop without a discrete GPU and it worked. As far as I can see bumblebee is a dead project. What is the alternative for Nvidia Optimus now on Ubuntu 18.04? I am using the Nvidia proprietary drivers, version 390, but it has only caused me problems like overheating (90+ celcius), screen tearring and now this HDMI problem.