Backstory: I've been developing a game with LibGDX for the past two years, and I've seen it refactored more times than I remember.  I jumped on the iOS iKVM port as soon as it was released. But I've been struggling with it ever since in regards to cross platform networking.  Kryonet will not port over to iOS unfortunately. So it's either I ditch Kryonet, or lose a large chunk of my target audience (iOS Users)  My question for you is:  I noticed LibGDX has cross platform classes ready for sockets and HTTP Requests, but no documentation exists for these sockets at all.  Has anyone used these sockets at all in the past, and does anyone know how they work?


Protect email addresses in the user description from bots

I've noticed that emails are not protected in the user description. For example  entered his email and when viewing the source code of the page it is plain text that malicious bots could harvest and exploit to spam. It would be nice if email addresses were automatically encoded to prevent this.


SQL query (Change csv id's to csv name's)

I have a query like this.  select pid,deptid from table1;  in which deptid is varchar and value like (1,3,4)  Now I have another table as department(deptid(int,PK), DeptName)  I want instead of get deptid from select I can get deptNames in csv.like  pid | deptname  1   | dept1,dept4,dept7  2   | dept4,dept9   What should be approach for this.


Use of "on" vs "in" when referring to one's place of employment

When should I write in or at while writing on a work place?  For example, should I write     Meet John, he is a data engineer in a gaming company.   or      Meet John, he is a data engineer at a gaming company.


How to interpret the notation $f(x) \equiv g(x) \hspace{2mm} (\text{mod} \hspace{2mm} h(x), \hspace{1mm} n)$?

I was told by my tutor to interpret the notation  $$ f(x) \equiv g(x) \hspace{2mm} (\text{mod} \hspace{2mm} h(x), \hspace{1mm} n) $$ as meaning that "$f(x)$ is equivalent to $g(x)$ in the polynomial quotient ring $\mathbb{Z}_n [x] / h(x)$".  Assuming that this is a correct definition of this notation, I am wondering how exactly to interpret this. Am I correct in thinking that this means that $$ f(x) \in \left\{ \hspace{1mm} g(x) \cdot h(x)^k \hspace{2mm} | \hspace{2mm} k \in \mathbb{N} \hspace{1mm} \right\} $$  For example, would $$ f(x) \equiv (x^2 + 1) \hspace{2mm} (\text{mod} \hspace{2mm} (x^4 + 1), \hspace{1mm} 2) $$ mean that $$ f(x) \in \left\{ (x^2 + 1), \hspace{1mm} (x^2 + 1)(x^4 + 1), \hspace{1mm} (x^2 + 1)(x^4 + 1)^2, \hspace{1mm} (x^2 + 1)(x^4 + 1)^3, \dots \hspace{1mm} \right\} $$


If the derivative tends to $0$ at infinity, then so does the function divided by $x$

Suppose that $$f\colon (a,\infty) \to \mathbb{R}$$ is differentiable, and that $$\lim_{x\to\infty} f'(x) =0. $$ Show that $$\lim_{x\to\infty} \frac{f(x)}{x} = 0.$$ This can be done easily with L'Hôpital's rule, but it appears as a textbook exercise, in a chapter discussing Rolle's theorem, Mean Value Theorem, etc., before L'Hôpital's rule is introduced.


my girlfriend's location history show her places on different days that she swears she had not been to. I s this info accurate


I want to print some posters but don't know where to look for Images which are not Copyrighted?

I started a new website for selling posters of Movies, Celebrities and Sports. Problem is most of the images that I got from Internet are now claimed by some people that they have copyrights of the images. I am trying to find the right Images but its very difficult for me. I looked in many free stock images website but was unable to get Images which are worth printing.


Injective functions between an interval and a square

A task given to us is about proving that the interval $X=[0,1]$ and the square $Y=[0,1] × [0,1]$ are equipotent.   Part 1 asks to find an injective function $f : X \rightarrow Y$  Part 2 asks to find an injective function $g : Y \rightarrow X$  I can't seem to find the answer to these two and I imagine they are more obvious than what it seems. I know that the Cantor-Bernstein-Schröder theorem has to be used eventually. Any help would be greatly appreciated.


I'm trying to match a pattern and then print out two lines after it. I'm successfully able to do it with the following code.  awk '/'202404'/{c=3}c&&c--' consolelog.log > testing.txt   I'm trying to replace the 202404 with something I can enter in the terminal. So far I have tried   echo "Enter peak value" read peak awk '/${peak}/{c=3}c&&c--' consolelog.log > testing.txt   But it does not work.   I don't necessarily need to use awk, grep or sed or anything will do. I just need to match a user inputted pattern and print 2 lines after it.   ***UPDATE***** I was playing around with it and I got it to work. It was something I totally missed. Here's what I did.  awk 'c&&!--c;/'$peak'/{c=2}' consolelog.log > testing.txt


I am wondering if there are any functions $f(x)$ such that it cannot be expressed as a power series of $x$? This might turn out to be a silly question, but I can't think of one at the moment.   Thanks!


One.java  public class One {      private void run() {         System.out.println("one");     }      public void start() {         this.run();     } }   Two.java  public class Two extends One {     public void run() {         System.out.println("two");     } }   Main.java  public class Main {     public static void main(String[] args) {         Two t = new Two();         t.start();     } }   Output: one  But if I declare the run method public in the One class I get "two" as output.  It is pretty unpredictable, how does this work?


Is it possible to add a hyperlink to an object or a layer within Illustrator CS6 for a later SVG export?  I know about the possibility to manually edit the exported file and wrap elements with an <a> tag. But this complicates subsequent changes. It would be better to have solution that is integrated in Illustrator.


Modifying existing code to sort a list of abbreviations

I have currently the Latex code written in the .cls file to display a list of abbreviations as follows:  \newcommand\listnomenclature{Abbreviations} \usepackage{longtable}  \newcommand\listofnomenclature[2]{ \btypeout{\listnomenclature} \addtotoc{\listnomenclature}     \chapter*{\listnomenclature       \@mkboth{           \MakeUppercase\listnomenclature}{\MakeUppercase\listnomenclature}} \begin{longtable}[c]{#1}#2\end{longtable}\par     \cleardoublepage }   It is used in the following way:  \listofnomenclature{ll}{ GHG     &   GreenHouse Gasses \\ CoMP    &   Cooperative Multi-Point \\ ITU     &   International Telecommunication Union \\ }   Is it possible to modify the codes in the .cls file so that the output is sorted alphanumerically without drastically changing the way it is used?


Understanding covariance matrix used in gaussian mixture model

Using python's "elliptic envelope" for gaussian mixture clustering (gmm), what does it mean by "spherical, diagonal, etc."? I can imagine that "diagonal" refers to a diagonal covariance matrix where only the diagonal elements are non-zero, but what do "tied, spherical and full" mean?


Is it possible to enumerate which types that is "available" in a generic constraint?  T MyMethod<t>() where T : int, double, string   Why I want to do this is that I have a small evaluator engine and would like to write code like this:  bool expression.Evaluate<bool>();   or  int expression.Evaluate<int>();   but i want to prohibit   MyCustomClass expression.Evalaute<MyCustomClass>();


Is there any technical difference between these methods?

I have been trying to learn OO JS. I was playing with different patterns, wrote following example.  var obj = function() {      this.a= function() {         return 'a';     }  }  obj.prototype.b = function() {     return 'b'; }    var instance = new obj();  console.log(instance.a()); console.log(instance.b());    Is there any difference here in function a and b?


How can I exclude the lines which matche the range patterns in sed?

I am writing sed expression which tries to print the text within a range of patterns:  apt-cache showpkg gdm | sed -n '/Reverse Depends:/,/Dependencies:/ p'   This basically works, current output is:  Reverse Depends:    libgdm1:i386,gdm 3.8.3-3~   ...   ...   gnome-control-center-data,gdm 3.0 Dependencies:    But I don't want the lines containing the patterns themselves, I want:    libgdm1:i386,gdm 3.8.3-3~   ...   ...   gnome-control-center-data,gdm 3.0   I know I can just just pipe the output to grep with -v option:  grep -v "Reverse Depends:"   But I hope sed has an option for it. I have tried  $ apt-cache showpkg gdm | sed -n '/Reverse Depends:/-1,/Dependencies:/-1 p'   But it doesn't work:  sed: -e expression #1, char 19: unknown command: `-'


Find all polynomials $p(x)$ such that $p(x^2)={p(x)}^2$

The question is      Find all polynomials $p(x)$ such that $p(x^2)=[p(x)]^2$.   First of all i saw that  $p(x)=0$ and $p(x)=1$ are two polynomials satisfying the condition. Next I tried putting some values and observed that  Since $p\big((-a)^2\big)=[p(-a)]^2$. Also, $p\big((a)^2\big)=[p(a)]^2$ Hence we can conclude - $p(-x)=p(x)$  Now my doubt is what to do next to find all possible polynomials or whether my approach is right or not .Any help would be appreciated.Thanks in advance.


Where are MLE equations such as $\sum_{i=1}^n \bigg(y_i - \frac{e^{x_i^T \beta}}{1+e^{x_i^T \beta}} \bigg)x_{ij}=0$ derived?

Where are MLE equations such as $$\sum_{i=1}^n \bigg(y_i - \frac{e^{x_i^T \beta}}{1+e^{x_i^T \beta}} \bigg)x_{ij}=0$$ for $Y_i \text{~} Bin(1, \pi_i)$ derived?


When I searched on the Internet for the reason of formation of , I got many explanations like  one & . All the explanations consider only one spherical water droplet (like ).  Why don't the refracted waves coming from the adjacent droplets interfere with each other? For example, why doesn't a red ray coincide with a violet ray coming from another droplet at a suitable position?   How are we able to see rainbows with distinct colors? Since there are thousands of raindrops in the sky when it is raining, shouldn't it be a mess due to overlapping of different wavelengths?  Please explain.


Does the set of all finite sets exist according to ZFC?

I know that there is no set of all sets in ZFC. Is there a way to manipulate the axioms and define a set of all finite sets? I am asking because if you think about it, the cardinality looks a lot like a function. You give me a finite set and I can tell you a number, which is its cardinality. Input-Output. However, in order for this to be a function, it needs to have a domain. So, can this domain be defined? Or do we have to say that there cannot be a function that given a set can return its cardinality?


Homeomorphism $(\mathbb{CP}^1)^m/S_m \overset{\sim}{\to} \mathbb{CP}^m$?

For each $m \ge 1$, how do I construct a homeomorphism $(\mathbb{CP}^1)^m/S_m \overset{\sim}{\to} \mathbb{CP}^m$?  My thoughts so far: I probably want to identify $\mathbb{C}^{m+1}$ with the vector space $\mathbb{C}^m[z, w]$ of degree $m$ homogeneous polynomials in two variables and use that a polynomial in one variable is determined by its roots up to a nonzero constant factor somehow... but from here, I'm kinda of stuck. Could someone help?  EDIT: Progress so far. After reading Eric Wofsey's response, I have the following. Since a projective variety is determined by its homogeneous coordinate ring, it suffices to determine the homogeneous coordinate ring of $(\mathbb{CP}^1)^m/S_m$.  For $(\mathbb{CP}^1)^m$, the coordinate ring is the graded ring $\mathcal{S}$ whose $d$th degree part is the $m$-fold tensor product (over $\mathbb{C}$) of $\mathbb{C}[s, t]_{d}$. That is, $S_d$ consists of polynomials in $s^1, t^1, s^2, t^2, \dots, s^m, t^m$ of multidegree ($d, d, \dots, d$). And $S_m$ acts in the obvious way, i.e. if $\sigma(i) = j$, then $\sigma$ sends $s^i$ to $s^j$ and $t^i$ to $t^j$. The homogeneous coordinate ring of $(\mathbb{CP}^1)^m/S_m$ is just the ring of invariants of the $S_m$ action on $\mathcal{S}$. But I still have two questions.   Which polynomials are invariant under this action? I still don't see how to conclude that Eric Wofsey's map is a homeomorphism. How do I see that Eric Wofsey's map is a homeomorphism?


Can the taxonomist badge be awarded more than once?   I would think so, but there are only 874 badges awarded and over 1500 tags that have been used 50+ times.  The definition states "Created a tag used by 50 questions"


Problem with Toshiba satellite c55t-c5300

I started working few months ago with Linux and decided to go all-in and switch from windows to linux. I installed ubuntu 16.04 and the wifi isn't working at all, tried lots of guides online with no luck about my specifications (no worries- after failing the first time I reinstalled it).  it will probably help to solve it quicker:  lspci -vnn | grep Network   gave me:   Network controller [0280]: Broadcom Corporation BCM43142 802.11b/g/n [14e4:4365] (rev 01)    Since I don't know much yet about this system a full guide will be more than appreciated.  Thank you, Danor


In the same way that \min and \max work, is there a version for "ave" meaning the average?  Thanks.


Is there any downside to transferring 401k to a rollover IRA?

I have a 401k retirement savings account from a previous employer. I am considering transferring it to a rollover IRA, where it seems I would have access to a larger range of investment options. However, I understand doing that would not be reversible, so I want to be 100% sure I am doing the right thing. Are there any downsides I should be aware of to transferring a 401k from a previous employer to a rollover IRA?


Do CSS class names have any effect on SEO?

I have seen some of our competitors using keyword-rich CSS class names. As an example, if I were in the pet grooming business, I would name my #menu as:   #menu.pet.grooming.moreKeywords.etc { ... }   Does this have any effect on SEO? If so, what is the best practice?


Can I map a 360° panorama as equirectangular image to a sphere, so that it resembles the original panorama inside out?


M1 BigSur keybind to swap "Option + ArrowKey" to "Control + ArrowKey"?

Is there anyway to change "option + arrow keys" to "control + arrow keys"? Essentially I want to be able to bind it just like windows. Move from word to word, delete by the word etc I was able to swap around the control/option/command key within the Keyboard settings but that's not necessarily what I'm looking for. I'm trying to get the actual functionality of "moving from word to word" by using the control + arrowKey.


"Destructor already defined" with a specialized destructor

I am experimenting with specialized destructors. This code is perfectly valid and compiles just fine:  #include <iostream>  using namespace std;  template <typename T> class Cat { public:     ~Cat(); };  template <typename T> Cat<T>::~Cat() {     std::cout << "T" << std::endl; }  template <> Cat<int>::~Cat() {     std::cout << "int" << std::endl; }   int main() {     Cat<int> c1;     Cat<float> c2;     return 0; }   However if I put the class and the destructors in a separate file "Cat.h" and do #include "Cat.h" in Main.cpp, I'm getting a linker error: LNK2005   "public: __thiscall Cat<int>::~Cat<int>(void)" (??1?$Cat@H@@QAE@XZ) already defined in Cat.obj. Why?


Give the "about" and "help" pages a more prominent location for anonymous users

It seems to me that two of the most helpful pages for introducing new visitors to the StackExchange network and methodology are the respective  and  pages of any StackExchange site.    However, if I go to  (where I have not registered), these two links are nowhere to be found!    No about or help here.  Oh, wait, here they are, relegated to the footer along with the privacy policy and advertising info links.    And we all know how often people look at a website's footer.  I mean, when was the last time you saw that footer?  If users had more of an opportunity to see the well-organized and important information on those pages before they were prompted to register for an account, we would see an improvement in the quality of posts and participation by new users.  I propose that these links be made more visible to new visitors who don't yet have a profile so they can get a better understanding of the website before being prompted to register for it.  Personally, I think that placing them next to "sign up" and "login" would be great, but increasing their visibility at all would be an improvement.


How to Extract a struct from byte array in C#?

I have a struct in C in my Embedded MCU, it's something like this  struct setting_registers { uint16_t CNT; char name[32]; float calibrate[4][16]; int some_setting; ... about 1000 elements! };   I have transferred the Struct into my C# app with serial port, now I have a byte array that contains my Struct from the MCU, something like this  int bytes = serialPort.BytesToRead; byte[] buffer = new byte[bytes]; serialPort.Read(buffer, 0, bytes);   Now I want to have a similar Struct or class in C# and extract every info from this received byte array, I wanted to do a brute force casting like this,   int CNT = 0; CNT = buffer[0]*256 + buffer[1] ;   But it will take ages! and if I change the struct in my MCU then I should do all sort of things by hand in C# code too! I wanted to know if there is a more clever way of doing it?  I have done the Struct serialization in the C inside the MCU like this  uint8_t objectPointer = (uint8_t)setting_registers;  //Send Object  for(uint16_t i=0;i<size_of_obj;i++) {       uart0_putChar(objectPointer[i]);  }   I mean I can cast the whole struct to a pointer and send it serialy. So if I just copy and past my big struct with 1000 elemnts to C# is there a way to do something like a for loop to copy the elemnts in the recived buffer into the Struct?


How to find the last two digits of $$(3^{1997})$$ ......  I tried to do $$(3^{1997})$$ (mod 100) . I reached on that $$3^{20}$$ is congruent to 1 (mod 100) .  But the calculation was getting very long after that . If anyone could correct me (or shorten) my method . Actually i have got the answer as 63 by this long process


Hyphenation of adjectives composed of three words

Hyphenating an adjective composed of two words is, from what I understand, fairly straightforward: if the adjective is before the noun, it must be hyphenated      The three-eyed raven   Customer-centric organizations     (with some exceptions such as not hyphenating after adverbs ending in -ly)     A highly efficient team   But how would one apply this to create an adjective from a composed word or expression and an adjective or past participle ? The example that comes to my mind is the following sentence:     Your product is based on big data     Which of these two options, if any, should I use, and why?     A big-data-based product   A big data-based product    Reading this, I think the second option does not mean what I want it to mean (it means that the product is big and based on data, not based on big data). The first option seems to make more sense, but is it correct?


What would be an example of a convex set in one dimension?

How can such a set exist in one dimension? What would this look like geometrically? I recently started learning about convex sets and I don't know how to visualise one in 1-dimension. Any help is appreciated. Thanks.


Why is 'that' sometimes optional before dependent clauses?

Sometimes, the word 'that' to introduce a dependent clause is optional.  For example, these sentences both make sense with or without 'that':  Long books [that] religious people like tend to be Bibles. Water tanks [that] fish need are spacious.  ... whereas in these sentences, 'that' is mandatory and the sentence is ungrammatical without it:  Those that are rotten must be thrown away. Cars that break down endanger pedestrians.  I can't quite put my finger on the rule which determines when 'that' must be used.  What is it?


Why are the ads shown on StackExchange of StackExchange websites and apps only?

Why are the ads shown on SE about SE websites and its android app only? I don't think that'll earn SE something. I'd says that almost every time, the ad is about SE network website and only a few times about other websites like:ProofWiki, MIT OpenCourseWare, etc. So why is it so?


My wife has a Nikon D3100 that I've been using to film, but the battery typically won't last through long shoots.  I've gathered from searching around that I can't charge the camera with USB, but I wondered if there's ANY way to do that. It seems at least possible that an adapter could exist that would fill in for the battery and plug into the wall, but I haven't been able to find such a thing.  Is there such a product or technique? It would be nice to not buy a second battery, I'm really hoping for a "set it and forget it" solution.


Here is my controller  public with sharing class Search  {      public String strTag {get;set;}     public String strlocation {get;set;}     public String result {get;set;}     public ResultSet data {get;set;}      public PageReference find() {               HttpRequest req = new HttpRequest();     HttpResponse res = new HttpResponse();     Http http = new Http();      req.setEndpoint('http://test.3spire.net/index.php?ins='+strTag+'&loc='+strlocation);     req.setMethod('GET');      //these parts of the POST you may want to customize     req.setCompressed(false);     req.setBody('key1=value1&key2=value2');     req.setHeader('Content-Type', 'application/x-www-form-urlencoded');        try {         res = http.send(req);            } catch(System.CalloutException e) {         system.debug('Callout error: '+ e);         result = ''+e;     }      data= JSON.deserialize(res.getBody(),ResultSet.class);  //    result = res.getBody();             return null;     }      public class ResultSet{                public Map<String, Result> resultSet;     }      public class Result     {         public String ins;         public String loc;     } }   And this is my visulforce page   <apex:pageBlock >     <apex:pageBlockTable value="" var="var" id="table">      <apex:column value="" />      <apex:column value="" />     </apex:pageBlockTable>  </apex:pageBlock>   Now how can i bind the data with the interface  Thanks in advance


How to convert between Cycles and Blender renderer?

I have set up a model in Blender and started refining material properties, lighting etc. around some imported geometry. It is looking good, but I would like a surface to represent the light scattering of woven carbon fibre.  I have found an  of a very good approximation, though I haven't yet fully figured out how it works. It works using Cycles renderer. When I switch to Blender's renderer in this project essentially nothing gets drawn (uniform grey).  However when I switch my model to Cycles renderer nothing (still uniform grey) also gets drawn. It seems like there is a fundamental difference in modelling strategy bewteen the two renderers.   How can I move from one technology to the other?  How can I know whether a technology I am trying to use is meant for one renderer or the other? Would it make more sense if there were two versions of Blender built around each renderer and only exposing the features that work with each? Perhaps the differences aren't as large as I'm suggesting.   Edit: I think the bigger question here is how I can know whether some tool I'm using is or is not compatible with the chosen renderer. As per the comments it seems that the internal renderer is being deprecated and Cycles or eevee is going to become king, how can I know I'm using the technologies compatible with it, without trial-and-error, use it, change it, render, see what happens?


Why does my Nikon D3100 give the error "Lens not attached" with a Vivitar 200 telephoto lens?

I have a Nikon D3100 camera, and am trying to use an "Automatic Fixed Mount Vivitar 200mm lens" with it. When I attach the lens, I get the message "Lens not attached". and nothing works. HELP!  I can't easily take it to a camera shop, as I live in the Mojave Desert, about 200 miles away from any camera shop. This is a new lens, and a new camera.


How can I achieve this effect where photos have a "bluish" theme with highly dramatic colors?

Just wanted to see how this effect can be achieve in the images in .  If you notice closely there is a 'bluish' theme in the pics yet colours are standing out and there is more drama in the pics.  I understand this is definitely something to do with post processing and perhaps something to do with curve.  I have client who has requested similar colour tone in pics and I have no idea how to do these properly. No matter what I try, I am not getting similar results.


By the dupe, the table implies $\,(14441,3565) = (3565,189) = \ldots = (28,21) = (21,7) = (7,0) = 7\ \ $ I understand that Euclid's algorithm on GCD is based on doing division via subtraction $x = qy + r$. I also understand that the process is keep expressing the quotient in terms of the remainder. Example to find GCD of $14441$, $3563$:     x    = q * y +  r     14441 4 3565 189   3565 18 189 161   189 1 161 28   161 5 28 21   28 1 21 7   21 3 7 0     So the GCD is $7$. So basically we try to divide the $2$ original numbers and then try to see if the remainder can express evenly $y$ and keep doing that recursively i.e. try to find the smallest number that divides the remainder. But I am not sure I understand the intuition behind the idea. Why would that process lead to the smallest number that divides the original $x$? I also read that a core idea is that $gcd(x,y) = gcd(y,r)$ but I didn't really get that part too. Could someone please help?


If a UA Artificer infuses a weapon and uses it as a spellcasting focus, can it be used for the somatic component of a spell too?

The new  for 5e can infuse magic into weapons or shields, and use the infused item as a spell focus for material components. However, can you wave your focus for the somatic part of a spell as well?  Basically, I am curious whether an artificer can have a one-handed crossbow in one hand, and an infused shield in the other and still cast V, S, M spells.


Why there isn't a feature that lets any user on SO to request other user to answer their question?

When I browse through other questions to find my answer, sometimes I'll find answers similar to what I'm looking for, and though they don't exactly answer my question, the author might be able to do so. Could we have a feature on SO that will let me request that another user answer my question, in case I find someone who could potentially answer my question?


Finding the electric field of a NON uniform slab?

If we have an infinite slab that is not uniformly charged and is not a conductor, how can we find an expression for the electric field everywhere? Here's a picture  Things we know about the slab:   The width is $2b$ It is lying on the $yz$ plane (centered at the origin) the charge density varies as $\rho = \rho_0(x/b)^2$   where $\rho_{0}$ is constant.  I know that I have to use Gauss's law with a right Gaussian cylinder. This is what I have so far:  The closed integral  $$\int EdA = \frac{q_\text{enclosed}} {\epsilon_{0}} \, .$$  To solve for $q_\text{enclosed}$, I believe it would be $\int ρdV$.  From here, I can plug in $ρ_0(x/b)^2$ for $ρ$ and $dV$ is just the area of the circle (I'll call that $A$) multiplied by $dx$.  So the integral becomes (by pulling out all the constants) $ρ_0(1/b^2)A\int x^2dx$ and I am integrating from $-b$ to $b$. Evaluating these bounds in this integral gives me a final answer of $q$ enclosed of $\frac{2ρ_0Ab}{3}$.


Use Insert Key to toggle insert/overwrite mode in Bash Terminal

After years of annoyance I finally setup Insert/Overwrite mode in Bash Terminal by creating this file:    $ cat ~/.inputrc  # ~/.inputrc - complements /etc/inputrc - global inputrc for libreadline # April 15, 2019 # See readline(3readline) and `info rluserman' for more information.  $include /etc/inputrc  Control-o: overwrite-mode   See:   I could always recall previous command with the ⭡ (Up Arrow) key and reposition the cursor for editing. I was always annoyed having to erase characters and insert new ones rather than replacing.  Now I can type Ctrl+O to turn off Insert Mode and type over existing characters. Then type Ctrl+O again to restore Insert Mode.  But how can I assign the Insert key instead of Ctrl+O to toggle overwrite-mode on and off?


How do I pass a function pointer from a class into another function in C++

I am having some trouble with passing a function that is a member of the class 'F' to a function that is the member of class 'X'.I get the error 'error: no match function for call to X::call()' Sorry if the solution is really simple, I'm still fairly new to C++ My code: #include <iostream>  using namespace std;  class X{ public:     void call (void (*func)()){         func();     } };  class F{ public:     void Function(){         cout<<"hello";     } };  int main() {     X x;     F f;      x.call(f.Function);      return 0; }  basically I'm just trying to pass the function from class F into class X call function. Thanks in advance for your help.


Is there a way to view the "newest questions" section with excluded tags? E.g.  Show all C#-tagged questions but not those which are also tagged with WPF


How to restore/add previous user account

I've recently  by reinstalling Ubuntu with a new username, and thankfully my old account survived (yay). Now I'd like to add my old account back to Ubuntu. Note that I'm not necessarily trying to overwrite the new user account. I just want to restore the old account and have it be the default when I boot up Ubuntu.  Edit I can create a new account under the old name but I'm worried that that will destroy the old account data.  Update  I've replaced the my new home folder with my old home folder but that didn't work.


Is "give an exam" grammatical for "writing the answers to exam"?

Amongst North Indian Students, the phrase "give an exam" is very popular. These students use the phrase to describe the act of writing the answers to examination questions.  The reason being, in Hindi, it's known as "exam dhena" which translates literally to "to give an exam".  In South India, however, a majority of people use the phrase "to take up an exam".  Which of these usages is more common/appropriate/grammatical? (As a prof I have developed a strange aversion toward the "give an exam" phrase; I find it wrong and ugly.)


Make all footnotes numbered subsequently, but one with a symbol

I was wandering if there's a way to make only one footnote appear with a symbol (*) instead of the number.  Thanks!!!


There is no group whose quotient by the center is isomorphic to the quaternion group

I have to prove that there is no group $G$ such that $G/Z(G)$ is isomorphic to $Q_8$.  Anytone can give me an idea to begin? thanks


Bounty, someone elses question and can't comment?

Ok so I recently posted a bounty on this , which is not my own. This has taken me from 90 reps to 40 reps. This leaves me in a situation where I can't comment on the question or answers, which subsequently means I can't e.g. ask for more information, that I think is necessary to (properly) award the bounty.   I know I should have thought about this before placing it, but is there any way around this situation?  Edit  The linked  although on the same lines as this one, was posted 2 years ago, with most comments saying it is a very rare event. The answers given thus relate to the situation 2 years ago and not now. Has the situation changed at all since then, or not?


I am working on blender using a friend's computer, and I cannot find the materials tab. I circled the red area where it is usually located for me.


How to test if certain assemblies have been loaded into memory?

I have some code that uses the Crystal Reports runtime libraries to generate and discard a small dummy report, in order to ensure that the libraries are loaded into memory in good time before the user creates a genuine report. (It's a 'perceived performance' issue.) The performance has been notably improved when the user generates a report, so that clearly all works.  Now I need to write a unit test that proves that the Crystal libraries have indeed been loaded into memory when expected - however my attempts to test what is there using Assembly.GetExecutingAssembly().GetModules() does not help. (GetCallingAssembly().GetModules() is no better either.)  How can I check from within my unit test to see if these assemblies have been loaded?  TIA


I have a Dell Dimension E510, with nothing on the disk but 14.04. However, it is running very slow. I don't know why, 11.10 and 12.04 ran fine.  How should I proceed?


Eldritch Knight/Warlock multiclass spellcasting

If a Fighter 3 (Eldritch Knight) levels up as a Warlock for the rest of the way to 20, making him an 18th level caster according to the multiclass spell slot table provided, would he in turn be able to learn 9th level spell? Meeting only the requirements listed for Warlock upon leveling, being 1 spell on it's list for which it has spell slots available for.  (Note: I would put up quotes and annotations providing source material but I'm running on limited time and my question sounds convoluted and simple to solve to the point where it's just me being dumb.)


Is it possible to track the event when a user manually locked the station (by pressing Windows + L) in event viewer or in the registry?   I am using Windows 7 Home Premium 64 bit.


Is there a way to not put the { next to the declaration on a dict variable in python?

Is putting the { next to the variable declaration required by syntax (for a dict variable) or is there a way to put it on the next line because if I do it like this I have to go through each item and check them until I find the item I want to change: var = {thingy1: 1, thingy2: 2, thingy3: 3, thingy4: 4, thingy5: 5}  I would like to do it like this: var = {     thingy1: 1,     thingy2: 2 }  I have seen some people doing it like this but I just want to know if putting the { next to the variable declaration is required by syntax or not: var = {     thingy1: 1,     thingy2: 2 }  (sorry if its a stupid question im a bad programmer and ive just started learning python lol)


Creating areas with different levels of resolution in the same model?

How can more resolution be added to certain parts of a model? For example, on this piece of popcorn the green areas need more detail. How can the whole model stay low poly and only quads while adding the extra detail?


Will I be allowed to go to Mexico without a visa if I hold a British and a Schengen visa?

I am currently living in the UK on a Tier 2 visa and have a multiple entry Schengen visa valid until 2022. Do I need a Mexican visa? The Mexican embassy in India told me I do not. However, VisaHQ in the UK told me I do. Will I need to apply for a visa? And if I don't, will I be allowed to board the flight?


Regular Expression creation for phone number

I'm trying to write a single regular expression to validate phone numbers. Below numbers should be   1111111111 or 111-111-1111 or 111.111.1111 - should fail and at the same time 767-789-9876 or 7677899876 should pass  I have come up with ^(?!([0-9])\1{2}[^d]\1{3}[^d]\1{4}$), but it only helps validate repetitive digits, alphanumeric characters and all succeed. Can anyone help me improve my regex?


I have the following string "Dec".  How can I convert this string to the month number 12?  I tried this:  DateTime.ParseExact("Dec", "MMMM", null).Month   This doesn't work.


How to HIDE everything in PUBLISH metabox except Move to Trash & PUBLISH button

I have a custom post type (called contacts). Since this post type is not working like a post, I don't want to show SAVE DRAFT, PREVIEW, Status, Visibility or Publish Date.  The only options I want to show are PUBLISH & Move to Trash buttons.   Is there a way to hide these other options? If not, how do I create a new PUBLISH & Move to Trash that I can add to a new metabox?


By starting with the double six, a full set of dominoes are used by a person to lay a line of dominoes in one direction only until the supply is is finished or you cannot carry on. What will the number at the end of the last domino and why?  I know the answer: it is 6 but I don't know how to prove it (since I actually tried to lay dominoes in one direction). Can anyone help me? The second part of the question says that the same method is used but on both directions of the double six. The person discovers that he can use all the dominoes that he has available, but someone says that he had hid one before he started. Can the person identify immediately (without checking the hole set) which domino has been hidden?


Method 1   public static synchronized Database getInstance(){    if(INSTANCE == null){      INSTANCE = new Database();    }    return INSTANCE; }   Method 2  private static final Database INSTANCE = new Database();     public static Database getInstance(){         return INSTANCE;     }   Which is the better choice ?


Show that $d_2$ defined by $d_2(x,y)=\frac{|x-y|}{1+|x-y|}$ is a metric

I am pretty sure that this is such a stupid, stupid question, but how do you prove that $d_2(x,y)={|x-y|\over {1+|x-y|}}$ satisfying the third condition to be a metric, which is the triangle inequality.   I know that I should really be able to do this, but I just can't, I keep seeing a contradiction. Please help me.


Nontrivial chain rule diagrams, how to write chain rule for them and is there implications or constraints in f that arises in the process?

(This is a short version of the question intended to post, because the original is just TOO LONG)  From  and various others (including 2 links deleted by the system as part of the clean up process, unfortunately...) we learnt how to manipulate partial derivatives rigorously.  We have learnt in undergraduate on how to write chain rules of multivariable functions using chain rule diagrams such as this one (variables that are kept constant are shown explicitly because the function is written in full)    $$\frac{\partial f(A(B,C),D(B,C)) )}{\partial B}=\frac{\partial f(A(B,C),D(B,C))}{\partial A(B,C)}\frac{\partial A(B,C)}{\partial B}+\frac{\partial f(A(B,C),D(B,C))}{\partial D(B,C)}\frac{\partial D(B,C)}{\partial B}$$  Or using another notation according to the link  $$\left.\frac{\partial f}{\partial B}\right|_C=\left.\frac{\partial f}{\partial A}\right|_D\left.\frac{\partial A}{\partial B}\right|_C+\left.\frac{\partial f}{\partial D}\right|_A\left.\frac{\partial D}{\partial B}\right|_C$$  Things looks fine. However when you have a function that look something like this     Attempt to write a chain rule gives a bizarre result for at least one of the variables  $$\left.\frac{\partial f}{\partial A}\right|_D$$ $$\color{red}{\left.\frac{\partial f}{\partial D}\right|_{A?}}=\left.\frac{\partial f}{\partial A}\right|_{D?}\frac{dA}{dD}+\color{red}{\left.\frac{\partial f}{\partial D}\right|_{A?}} \hspace{12 mm} [*]$$  If we consider the red terms identical, then we get $$0=\left.\frac{\partial f}{\partial A}\right|_{D?}\frac{dA}{dD}$$     Why the bizarre result? How to interpret or explain it (both geometrically and mathematically?)


I have a a file containing about 20 million sentences, how can I extract 2 million sentences out from it?  I thought about using the split command like this "split -l 2000000 sub2016", but then it will create a series of texts, while I just need one.  So how can I specify it? Thank you!


Rendered image is only a transparent screen

I was doing a roblox gfx, but when I rendered it, all I was seeing was a transparent screen, here is a screenshot:


Is it touch(1) from coreutils-8.4-37.el6.x86_64 or my brain which is broken?  $ touch abc $ LANG=C stat abc   File: `abc'   Size: 0               Blocks: 0          IO Block: 4096   regular empty file Device: fd04h/64772d    Inode: 10485773    Links: 1 Access: (0664/-rw-rw-r--)  Uid: (3060399/ nodakai)   Gid: (  418/   quant) Access: 2016-10-14 18:42:06.189751847 +0800 Modify: 2016-10-14 18:42:06.189751847 +0800 Change: 2016-10-14 18:42:06.189751847 +0800 $ touch -a abc $ LANG=C stat abc   File: `abc'   Size: 0               Blocks: 0          IO Block: 4096   regular empty file Device: fd04h/64772d    Inode: 10485773    Links: 1 Access: (0664/-rw-rw-r--)  Uid: (3060399/ nodakai)   Gid: (  418/   quant) Access: 2016-10-14 18:42:17.374235446 +0800 Modify: 2016-10-14 18:42:06.189751847 +0800 Change: 2016-10-14 18:42:17.374235446 +0800 $ touch --help | grep 'access time'   -a                     change only the access time   As you see, it was not only atime but also ctime which was updated by touch -a !?!?  The filesystem is ext4 over LVM if that makes any differences.


I'm writing C++ code on a mac. Why do I get this error when compiling?:     Undefined symbols for architecture i386:   "Log::theString",   referenced from:         Log::method(std::string) in libTest.a(Log.o) ld: symbol(s) not found for architecture i386 clang: error: linker command failed with   exit code 1 (use -v to see invocation)   Not sure if my code is wrong or I have to add additional flags to Xcode. My current XCode configurations are the default ones for a 'static library' project.  My code:    Log.h------------  #include <iostream> #include <string>  using namespace std;  class Log{ public:     static void method(string arg); private:     static string theString ; };   Log.cpp ----  #include "Log.h" #include <ostream>  void Log::method(string arg){     theString = "hola";     cout   << theString << endl;  }   I'm calling the 'method' from a test code, in this way: 'Log::method("asd"):'  thanks for your help.


Prove that the following statements are equivalent.  1-) The Cartesian product of a non-empty family of non-empty sets is also non-empty, i.e, $\{A_i: i \in I\}, I\neq \emptyset, A_i \neq \emptyset \Rightarrow \Pi _{i \in I} A_i \neq \emptyset$  2-) all non-empty collection of non-empty sets admits function choice, i.e, $\tau \neq \emptyset , \forall A \in \tau , A \neq \emptyset  \Rightarrow \exists f:\tau \to \bigcup \{A: A \in \tau\}$ where $A \to f(A) \in A$  I can not get started


Looking for the title of a movie I saw years ago. There was personal ports on hand

Everyone has his own port on his hand. Ports was kind of living thing, soft and reshapable. I have only a view in my memory. The idea was awesome. I would like to see the full movie.


Prove that $A \subset B$ if and only if $A \setminus B = \emptyset$.  What is the correct and mathematically strict way to prove the above? (slightly different than  )


Attempt to invoke virtual method 'java.lang.String com.marsad.earningapp.model.RegisterModel.getName()' on a null object reference

(sorry for my bad English) I'm trying to load data from Firebase database.  The app works fine and also load data form Firebase Database.  But then the app starts crashing. I don't know how to solve this.  Here is the MainActivity.this  public class MainActivity extends AppCompatActivity {       CircleImageView profileImage;      FirebaseAuth mAuth;     FirebaseAuth.AuthStateListener listener;     FirebaseDatabase userDatabase;     DatabaseReference reference;     FirebaseUser user;     String firebaseid;      private String email, name, phone, password, image;      @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main);          getSupportActionBar().hide();          profileImage = findViewById(R.id.profile_image);         username = findViewById(R.id.userName);          userDatabase = FirebaseDatabase.getInstance();         reference = userDatabase.getReference();         mAuth = FirebaseAuth.getInstance();         user = mAuth.getCurrentUser();          assert user != null;         firebaseid = user.getUid();          reference.addValueEventListener(new ValueEventListener() {             @Override             public void onDataChange(@NonNull DataSnapshot dataSnapshot) {                  for (DataSnapshot ds : dataSnapshot.getChildren()){                     information.setName(ds.child(firebaseid).getValue(RegisterModel.class).getName());                     information.setPoints(ds.child(firebaseid).getValue(RegisterModel.class).getPoints());                     information.setImage(ds.child(firebaseid).getValue(RegisterModel.class).getImage());                      username.setText(information.getName());                     totalPoints.setText(Integer.toString(information.getPoints()));                     String image = information.getImage();                      try {                         Picasso.get().load(image).into(profileImage);                     } catch (Exception e){                         Picasso.get().load(R.drawable.user).into(profileImage);                     }                  }              }              @Override             public void onCancelled(@NonNull DatabaseError databaseError) {                  Toasty.error(MainActivity.this, "Error: "+ databaseError.getMessage(),                         Toasty.LENGTH_SHORT, true).show();             }         });      }   }    Here is the Logcat  java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String com.marsad.app.model.RegisterModel.getName()' on a null object reference         at com.marsad.app.MainActivity$13.onDataChange(MainActivity.java:290)         at com.google.firebase.database.core.ValueEventRegistration.fireEvent(com.google.firebase:firebase-database@@19.2.1:75)         at com.google.firebase.database.core.view.DataEvent.fire(com.google.firebase:firebase-database@@19.2.1:63)         at com.google.firebase.database.core.view.EventRaiser$1.run(com.google.firebase:firebase-database@@19.2.1:55)         at android.os.Handler.handleCallback(Handler.java:790)         at android.os.Handler.dispatchMessage(Handler.java:99)         at android.os.Looper.loop(Looper.java:192)         at android.app.ActivityThread.main(ActivityThread.java:6711)         at java.lang.reflect.Method.invoke(Native Method)         at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:549)         at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:826)    Here is the Firebase Database structure (JSON)  {   "Users" : {     "nftLFXoEzPNyTt4OnZByVGClWJM2" : {       "email" : "test@gmail.com",       "image" : "https://firebasestorage.googleapis.com/v0/b/earning-app-27780.appspot.com/o/UsersProfileImages%2F1581504377418.jpg?alt=media&token=14484015-3b3c-4ff4-aa1c-7b5f3ffbe695",       "name" : "Marsad",       "password" : "123456",       "phone" : "03012345678"     }   } }   I don't know how to solve this.  Anyone please tell me how to solve this error


I have page where users can upload a photo to the browser with jQuery but I am now trying to figure how to actually save the photo by sending it to a php script. I understand the php side but don't know how with Jquery to send the photo to php. Do I need to put the input within a form?  jQuery  $(document).ready(function() {     var readURL = function(input) {         if (input.files && input.files[0]) {             var reader = new FileReader();              reader.onload = function (e) {                 $('.profile-pic').attr('src', e.target.result);             }              reader.readAsDataURL(input.files[0]);         }     }      $(".file-upload").on('change', function(){         readURL(this);     });      $(".upload-button").on('click', function() {         $(".file-upload").click();     }); });   HTML

 Upload Profile Image

                                  <form>                     <input class="file-upload" id="userImage" type="file" accept="image/*"/>                 </form>


how do I output multiple files with a heading for each one but without needing to page through them?

I am running a file search command with ag -g foo and I'd like to see the contents of the files I find. If I do ag -g foo | xargs more then the more command makes me press the spacebar to advance between each file, even though they are small enough that I could see more than one at a time in my terminal window. If I do ag -g foo | xargs cat then I see everything at once, but the files are mushed together so it's hard to see where a new file starts. Is there a way to see the files all in one scroll, but with a heading for each one?


Are Generation 1 Pokémon still able to hatch from eggs if they have a Generation 2 preevolution?

Within a Pokémon evolution family, only the first Pokémon is available from an egg.  For example, in the Bulbasaur family - Bulbasaur, Ivysaur, and Venusaur - only Bulbasaur can be hatched from an egg.  But now as generation 2 Pokémon have been introduced, some of those evolve into the generation 1 Pokémon, which are also available from eggs.  For instance, Cleffa evolves into Clefairy. Clefairy was able to be hatched before the update, but I don't know now as Clefairy is generation 1 whilst Cleffa is generation 2.  So are those generation 1 species still able to hatch from eggs?


Switch from Intel GPU to Radeon on Lubuntu?

I just installed Lubuntu on an old HP Envy 17 with Radeon 6850M The machine boots up using the integrated Intel GPU. How do I switch to the Radeon GPU? I haven't manually configured X since the XFree86 days :)


Continuity of a function $f:X \longrightarrow Y$ Where $X,Y$ metric space

I know most of the result regarding Continuity, Completeness. But I got stuck into a question which I found in a question paper. Let $f:X \longrightarrow Y$ Where $X,Y$ metric space.Then show that for any Cauchy sequence $\{x_n\}$ in $X$ if $\{f(x_n)\}$ is Cauchy in $Y$, then $f$ is continuous. Please help me. Thanks in advance.


sequence of positive numbers satisfying $a_{n+1}=\frac{2}{a_n+a_{n-1}}$, prove it converges

Assume that $(a_n)$ is a sequence of positive real numbers satisfying $a_{n+1}=\frac{2}{a_n+a_{n-1}}$ for $n=2,3,\dots$.  Prove that $(a_n)$ is convergent and find the limit.    I have no idea how to prove convergence. I tried to prove that $(a_n)$ is bounded and monotone, but both trials failed.  If convergence is proven, the limit is easy: if $g=\lim a_n$, then $g\ge 0$ because all $a_n$'s are positive, the equivalent relation $a_{n+1}(a_n+a_{n-1})=2$ gives $g(g+g)=2$, so finally $g=1$.


'pagesize' attribute ignored in hot network list

Steps to reproduce:   Open  in Guest/Incognito mode or with cookies disabled. This will have 30 questions per page by default. Click the  link and as expected, you'll see questions 1-50 with page size of 50. Go the the  and see the bug: you're in the second page of 30 items per page, i.e. you'll see questions 31-60 instead 51-100 as expected.     It is very annoying. Please fix it.  My user-agent is: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:70.0) Gecko/20100101 Firefox/70.0  There are no plugins installed affecting the site. It happens both when logged in or not.  The mechanism used to work before, but some weeks/months ago it stopped, enough to bother me to post here :)  Here are all modified "privacy" settings from about:support page:  privacy.clearOnShutdown.offlineApps true privacy.clearOnShutdown.openWindows true privacy.clearOnShutdown.siteSettings    true privacy.cpd.offlineApps true privacy.cpd.openWindows true privacy.cpd.passwords   true privacy.cpd.siteSettings    true privacy.donottrackheader.enabled    true privacy.history.custom  true privacy.item.cookies    true privacy.sanitize.migrateClearSavedPwdsOnExit    true privacy.sanitize.migrateFx3Prefs    true privacy.sanitize.pending    [{"id":"shutdown","itemsToClear":["cache","cookies","offlineApps","history","formdata","downloads","sessions","siteSetti privacy.sanitize.sanitizeInProgress ["cache","cookies","offlineApps","history","formdata","downloads","sessions","siteSettings","openWindows"] privacy.sanitize.sanitizeOnShutdown true privacy.sanitize.timeSpan   0 privacy.trackingprotection.enabled  true privacy.trackingprotection.introCount   20


Ordering in the right size, and making sure it fits

I'm fairly tall (6'4" or 195cm), and the bike I'm looking for is fairly specialised these days (a tourer, presumably steel, possibly with a sideline as a gravel bike/off-road tourer but no need for full-on CX specs and I need heel clearance).  I ride a hybrid.  My total road bike miles add up to about the same as a decent ride on my hybrid (42 miles) and those were on a too-small bike. So I'm not familiar with road bike fit.  I do know that if I can get the saddle high enough I'll be OK for easily an hour in the saddle of anything.  Nowhere stocks a range of tourers in my size. Even finding one single tourer in stock in my size is rare (tourers don't sell fast).  Of course many places can get one in, try to fit it, fail, send it back, try again...  But how do I maximise my chances of getting it right first time?  I don't see that a rough fit on a typical road bike or even a CX bike would be very informative, as I'm after the long wheelbase, relaxed geometry of a tourer.  It feels like I could extrapolate as well from flat bars. I'd almost be glad if these assumptions were wrong, but I might take a little convincing.  The next step of course is testing it to make sure it fits -- with everything set nominally right it will feel a bit odd as I'm used to flat bars.  How can I tell whether this is bad-odd or OK-odd in a short test ride?  Part of my concern is that I'm looking at the , and I'm at the top end of the largest size -- by some shops' size guides I should be OK, but not according to others (including the one I may buy it from)


AamazonAWS malware in my ubuntu 12.04 LTS

I need your help. Today I found (using wireshark) many requests are being thrown from my system to some other system and vice-versa. When I did the reverse DNS then I found it is AMAZONAWS malware.  Can any one please give me solution on how to tackle it.  Need Help Thanks


Does having an extended validation SSL certificate increase your Google search ranking?

I am assisting an retailer obtain and install an extended validation (EV) SSL certificate for their online shop. After a week of back and forth paperwork with the CA, I wonder whether it's worth the time and expense of getting one.   CAs, of course, claim it makes your site more trustworthy. There are numerous articles, however, arguing users can't tell the difference and don't care. Moreover, most modern browsers no longer make a visual distinction between EV and standard certificates.  Clearly, EV certificates lost the clout it once had, but I wonder if Google's ranking algorithm still gives it a higher weight. I suspect it's at least a small factor for smaller online retailers, but less, or none at all, for those that have been "prevalidated" by the virtue of buying Google Ads.


Unpaired t-test: large samples, unequal variances, unequal sample sizes

I a have two independent samples one with more than 700 observations and the second with more than 500 observations. I firstly use Cramér-von Mises test to test normality just to check how non-normal the distribution of the datasets is. It returned me p-value equal to 0. Thus, I have to rely on CLT (hope that I have enough observations - or should I rather somehow "test" that?). I then used Conover test to test equality of variances and it again returned me p-value equal to almost zero. Therefore, I want to compute the unequal variance t-test (Welch test), but I am wondering whether it was better to used standard Student's t-test because as I understand that due to the Lindenberg CLT, we can disregard the unequality of variances. So, generally, which test should I use? And was the above-mentioned testing of data reasonable?


Last night I was working on installing vsftpd on my Ubuntu 12.10 server. I shutdown last night and when I booted up this morning I seemed to have lost the abilities to sudo anything. It just says, "** is not in the sudoers file. This incident will be reported." Now I wasn't messing with any sudo files, just /etc/vsftpd.confg and /etc/shells. So how did I seemingly lose sudo ability? I'm rather new to Linux in general, but I'm picking it up quick.


Editing the "Your communities" list does not reflect changes after clicking "Save"

When adding/removing sites from "Your communities", the changes appear while editing, and are still present when clicking "edit" again, but are not visible after clicking "save". It takes a page reload to update the dropdown.


Proving Every open set in $\Bbb R$ is a countable union of open intervals.

This question is from William R. Wade's Introduction to Analysis book:  Prove that every open set in $\Bbb R$ is a countable union of open intervals.   I have no ideas honestly. Thank you.


What is the moment generating function of the generalized (multivariate) chi-square distribution?

To be specific, suppose we have $(n,1)$ random vector $x \sim N(\mu, \Sigma)$ where $\mu$ is $(n,1)$ and $\Sigma$ is $(n,n)$. Define: \begin{align*} Y & = x'Ax + b'x + c \end{align*}  Then what is the following (for $t \in \mathbb{R}$)?  \begin{align*} E(e^{tY}) \end{align*}


this is my first day with blender. Wow steep learning curve.  I keep losing my palettes. I'm down to two on screen and they haven't got little triangles in the corner so I can't drag to make more.   I don't seem to have collapse menus ticked. All I have on the Rhs is a a thing with transform which seems to be part of the 3d view window which is open. I can collapse and restore it with + but Previously I had palettes with a object tree and all sorts.  If I reload the app all is restored but as soon as I load the file I'm working on they go again. I suppose I could make a new doc and import but I'd like to know what I'm doing wrong.  Opening user preferences gave me a window with triangles and I was able to rebuild the UI in that but if I ever close the original window the app shuts down. Confused... Is there any way to make the new window 'primary' or to stop the UI being loaded with the file?  Thanks  Update: Hurray!!! I finally figured this out.  it happens if you go into the file open dialog and then instead of pressing OPEN or CANCEL, you use the window chooser to go back to 3D view. it leaves you with no drag handles.  The way to get out of it is to use the window chooser to go back into the  file open dialog and OPEN or CANCEL.


Prove that if G is hamiltonian then Line graph of G is hamiltonian too I know that we have a closed path with all vertices included then because every edge in this path is connected to two other edges then there will be a hamiltonian cycle in L(G) too and if we add the edges which are not in hamiltonian cycle L(G) is still hamiltonian


I'm using winforms with xna. Everything's working so far except for the drawing because invalidate won't refresh the screen unless repeated. This is the initial code I had:           protected override void Draw()         {             GraphicsDevice.Clear(Color.CornflowerBlue);             spriteBatch.Begin();             tileSheet.Draw(spriteBatch);             foreach (Image img in selector)                 img.Draw(spriteBatch);             spriteBatch.End();         }   I placed a breakpoint and it is calling the draw method but nothing is changing on the screen but when I do this:   protected override void Draw()     {         GraphicsDevice.Clear(Color.CornflowerBlue);         spriteBatch.Begin();         tileSheet.Draw(spriteBatch);         foreach (Image img in selector)             img.Draw(spriteBatch);         spriteBatch.End();          Invalidate();     }   It works! but the problem is that everything gets frozen and it seems to get caught up in an Invalidate loop. But why does the latter work but not to former? I've been working at this for hours now and I can't understand what's going wrong :/.   I feel like it's something simple but I can't wrap my head around it.   ps. I've also tried Update and Refresh and they don't work either.


Is it safe to use the hash of the data as the key to encrypt them?  That is, if I give one some encrypted data and tell them that the key that was used to encrypt them was the hash digest of the data before encrypting, will it be easier for them to decrypt them?  Edit as I can not reply to comments: The recipient will have the keys, that is no problem.


I have written this regex to validate an email address. The rules I have to follow are:  The recipient name may be a maximum of 64 characters long and consist of:   Uppercase and lowercase letters in English (A-Z, a-z) Digits from 0 to 9 Special characters A special character cannot appear as the first or last character in an email address or appear consecutively two or more times   [a-zA-z0-9]{1}?![a-zA-z0-9]?[a-zA-z0-9]{1,63}@[a-zA-z0-9]+\.[a-zA-z0-9]+  I am obviously new to Regex. What I meant by this line was, the first character has to be one of the [a-zA-z0-9] then, it is optional to use any special character by negating the [a-zA-z0-9] and then again use [a-zA-z0-9] before @.  Please help me to fulfil the above expectations.   Tnx


Propose a privilege to sit in the 500 reputation mark

As , the retag privilege serves a lot more confusion and a lot less of its benefit due to the suggested edit system. It must be done away with. It will be done away with. ♪  In light of this decided course of action, we're going to need a new snack for the road between "Create Tags" at 300 reputation and "Established User" at 1000 reputation. We'd like your help in thinking about some ideas on what would be a nice privilege to sit at this level. Since we're... a bit dry on our end.  The primary guideline in deciding what kind of privilege to put here is acknowledging its position in the overall hierarchy of privileges. 500 reputation is an early-intermediate user, one who has started to really get the hang of the site and its function. It can be something that provides convenience in how they currently can act on the site, or it could be some new functionality that fits as an early ability (especially considering there's no new abilities until 2000 reputation's "Edit Everywhat" ability).  I look forward to hearing what creative ideas y'all can provide.


Problem : Given $f(x) = x + |x|$ for what values of $x$ is $f$ differentiable?   For the sake of generality, let's assume that it is unknown to us that $|x|$ is not differentiable at $x = 0$  Attempted Solution :  Using the definition of differentiability, a function is differentiable over an interval $I$ $\text{iff}$  $$f'(x) = \lim_{h \to 0} \frac{f(x+h)-f(x)}{h}, \ \ \forall x\in I$$  Now implicitly this definition of differentiability requires $$\lim_{h\to 0^+} \frac{f(x+h)-f(x)}{h} = \lim_{h\to 0^-} \frac{f(x+h)-f(x)}{h}$$  Therefore $f$ will be differentiable only when  $$\lim_{h\to 0^+} \frac{(x + h + |x+h|)-(x + |x|)}{h} = \lim_{h\to 0^-} \frac{(x - h + |x-h|)-(x + |x|)}{h}$$  But it is unclear what to do next as $x$ is just arbitrary $$ \begin{equation} \begin{aligned} |x+h| &= \begin{cases}x+h & \text{if} & x \geq -h\\ -x-h & \text{if} & x < -h \end{cases} \\ &= \begin{cases}x+h & \text{if} & x \geq 0\\ -x-h & \text{if} & x < 0 \end{cases} \end{aligned} \end{equation}$$    A Wrong Solution :  We could take the derivative of $f$, (and evaluate the domain of the derivative $f'(x)$ to values for which it is defined), using the rules of differentiation, but we would get a wrong answer.  $$f'(x) = \frac{|x| + x}{|x|}$$ $$\implies f'(x) = \begin{cases} 2 & \text{if} & x \geq 0 \\ 0 & \text{if} & x < 0 \end{cases}$$  This implies the derivative $f'(0)$ exists, when it does not as per the definition of differentiability. Why is that so?    Questions:   How can a solution be found using the definition of differentiablity? Why does taking the derivative of $f$, $f'(x)$ and evaluating it's domain, not give the correct values of $x$ for which $f$ is differentiable?


What is the algorithm for computing quantiles?


Named destinations by hyperref broken for XeTeX 3.14159265-2.6-0.99992 (TeX Live 2015/dev/Debian)

We have this testcase which works fine with pdflatex  \documentclass[en]{article} \usepackage[  pdfauthor={Silly testcase maker},  pdftitle=,  pdfsubject=,  ]{hyperref}  \newcommand{\pdfLabel}[1]{\hyperdef{marker}{#1}{}}  \begin{document}  Hello folks \newpage haha this is funny \newpage lets do another page \newpage now we have a working testcase for real huh \newpage but rly this is the label \pdfLabel{hahalulz} that was the label \newpage but does it jump \newpage that is the question folks  \end{document}   The purpose is to define a named destination within the PDF document called marker.hahalulz. This used to work with xetex when using debian squeeze, but now with debian Jessy it fails with xelatex (but still works with pdflatex) and we have no idea what the reason might be.   The failure-symptoms are that we are unable to jump to the named destination, for example with the command  $ evince -n "marker.hahalulz" testcase.pdf   Output of xelatex  This is XeTeX, Version 3.14159265-2.6-0.99992 (TeX Live 2015/dev/Debian) (preloaded format=xelatex)  restricted \write18 enabled. entering extended mode (./testcase.tex LaTeX2e <2014/05/01> Babel <3.9l> and hyphenation patterns for 79 languages loaded. (/usr/share/texlive/texmf-dist/tex/latex/base/minimal.cls Document Class: minimal 2001/05/25 Standard LaTeX minimal class ) (/usr/share/texlive/texmf-dist/tex/latex/hyperref/hyperref.sty (/usr/share/texlive/texmf-dist/tex/generic/oberdiek/hobsub-hyperref.sty (/usr/share/texlive/texmf-dist/tex/generic/oberdiek/hobsub-generic.sty)) (/usr/share/texlive/texmf-dist/tex/latex/graphics/keyval.sty) (/usr/share/texlive/texmf-dist/tex/generic/ifxetex/ifxetex.sty) (/usr/share/texlive/texmf-dist/tex/latex/oberdiek/auxhook.sty) (/usr/share/texlive/texmf-dist/tex/latex/oberdiek/kvoptions.sty) (/usr/share/texlive/texmf-dist/tex/latex/hyperref/pd1enc.def) (/usr/share/texlive/texmf-dist/tex/latex/latexconfig/hyperref.cfg)  Package hyperref Warning: XeTeX driver only supports unicode. (hyperref)                Enabling option `unicode'.  (/usr/share/texlive/texmf-dist/tex/latex/hyperref/puenc.def) (/usr/share/texlive/texmf-dist/tex/latex/url/url.sty))  Package hyperref Message: Driver (autodetected): hxetex.  (/usr/share/texlive/texmf-dist/tex/latex/hyperref/hxetex.def (/usr/share/texlive/texmf-dist/tex/generic/oberdiek/stringenc.sty) (/usr/share/texlive/texmf-dist/tex/latex/oberdiek/rerunfilecheck.sty)) (./testcase.aux)  Package hyperref Warning: Height of page (\paperheight) is invalid (0.0pt), (hyperref)                using 11in.  (/usr/share/texlive/texmf-dist/tex/latex/hyperref/nameref.sty (/usr/share/texlive/texmf-dist/tex/generic/oberdiek/gettitlestring.sty)) (./testcase.out) (./testcase.out) [1] [2] [3] [4] [5] [6] [7] (./testcase.aux)  ) Output written on testcase.pdf (7 pages). Transcript written on testcase.log.


How to change the text Bibliography to References in scrreprt

\documentclass{scrreprt}  . . .  \addcontentsline{toc}{chapter}{References} \begin{thebibliography}{ZZ}   \end{thebibliography}   What should I add to these lines?


I read on the :     Focal-length determines the angle-of-view seen through a lens for a   given sensor-size. With a full-frame sensor a lens gives the same   angle-of-view as it would on a 35mm film camera. With a smaller   sensor, the angle-of-view becomes smaller. The crop-factor, also   called FLM, is the ratio representing the difference in equivalent   focal-lengths. So a 150mm on a full-frame DSLR such as the Nikon D700   gives the same angle-of-view as a 100mm on a D7000 since its FLM is   1.5X.      Short focal-lengths show a greater angle-of-view compared to longer   ones. [...]   In layman's terms, what is angle-of-view? Is it the same as focal length? If not, how is it different? How is it used? Why do I need to know about it?


While reading a datasheet for an IC I came across the pin voltages being presented as 3V3 or 1V8. What does this representation stand for?


Let $R$ be a ring with $1$ and $M$ a left $R-$module. The module $M$ is said to be uniserial if the poset of submodules of $M$ is a chain. Let $M$ be a  uniserial module and $\alpha,\beta\in End_R(M)$.      Why we have:  $\alpha\beta$ is injective if and only if both $\alpha$ and $\beta$ are injective.   Thanks in advance


Devuan - how to install non-free contrib?

I'm on transition from Mac OS-X to Devuan. Trying to make the learning curve not as steep, I need to install some non-free software. Reading through forums, I understand there is a command that will allow me to install Dropbox, skype, bluetooth audio outputs, etc. etc.on my system. I know this is highly discouraged, but I need these apps so as to let go of my Mac completeley, and then slowly do the complete migration into free software.


How exactly does lighting affect combat?

I understand that there are different types of lighting (dim, bright, complete darkness), but I haven't been able to find anywhere in the DMH or PHB that specifically describes how these different types of light sources affect combat.   What impact does complete darkness have on players being able to see the locations of the monsters in the room? What impact does complete darkness have on combat rolls against monsters? Could anyone point me to a book/page that contains some more detailed information on this?   Thanks!


How to set multiple camera views in one scene?

Is it possible to have several different views of one scene and set them as named "presets"?


$a, b$ are relatively prime and $a > b$.  Prove that $\text{gcd}(a-b,a+b) = 1 \,\,\text{or}\,\, 2$.   Attempt: Since $a, b$ are relatively prime, I know that $\text{gcd}(a,b) = 1$.  Also, know that $ax + by = 1 \,\,\text{for some}\,\, x,y \in \mathbb{Z}$.  Not sure where to go from there.  I suppose a proof by contradiction with the assumption that $\gcd(a-b,a+b) \neq 1 \,\,\text{or}\,\, 2$.  Thanks.


Backing up file groups with restore to earlier backup

I have a task: I have created a database with a filegroup lamb that has a few tables.  I need to extract a csv into a table in a filegroup named lamb and back up that filegroup.  Then extract another csv file again and back up again.  But I need to be able to restore the first backup.  What is the backup and restore method? Is it possible to restore only the lamb filegroup?


How to generate a SecureRandom number with a specific bit range

I have maximum number of bits that is not bit aligned E.g. 35 and required to generate unique random number from 1 - 68719476734 (max number for 35 bits). Could use SecureRandom but will have to extract 5 bytes out of it and convert to Long maybe, but chances of collision seem to a concern. What are some options to generate a random for this range. Could i seed this random with nanoTime maybe if there is a collision and regenerate in this range.


Does the Disciplined badge not show up in achievements?

I had occasion to delete a score = 3 answer yesterday (legitimate reasons - I'd misinterpreted the question). I got the Disciplined badge, but the achievements list doesn't show it. It does show the grep tag bronze badge I got on U&L today, and a Good Answer badge from Meta AU three days ago.  Is this by design?


Is it possible for MinecraftLauncher console to stay?

The Minecraft console disappears and the Minecraft Java game loads after the game output is loaded. Is it possible for it to stay? I would like to see the game output.


Microsoft Defender Antivirus is disabled, but back to normal after reboot. How to disable it permanently?

I have Windows 10 ver 2004. Since Windows Defender changed to Microsoft Defender Antivirus I'm unable to turn it off. In Local Group Policy (gpedit.msc) under Computer Configuration/Administrative Templates/Windows Components/Microsoft Defender Antivirus there is a key "Turn off Microsoft Defender Antivirus". Every time I check "enable" and log out or reboot the key is back to "Not configured". How to keep it disabled permanently, and therefore turn off Microsoft Defender Antivirus essentially?  (source: )


Double-clicking a vote button on a proposed question for a site already in beta creates an unclosable notification box

If you go to the definition page for a site already in beta (e.g. ) and double-click on the voting button, a notification box shows up that cannot be closed by clicking the "cancel" button.    The box still goes away (and is replaced by another box at the appropriate location) if you click on a different voting button, though.   My browser is Chrome 34 on Windows 7. I don't see any errors in the JS console.


Compact subspace in the union of closed embeddings

Let $f_i:A_i\rightarrow A_{i+1}$ be a sequence of closed embeddings of topological spaces. Denote $A:=\text{colim}_iA_i$ which is basically a union of all $A_i$ and we say that $U\subset A$ is open (closed) iff $U\cap A_i$ is open (closed) for all $i$. Let $K\subset A$ be a compact subspace. Then there is $i$ such that $K\subset A_i$.   I tried to prove it by contradiction: suppose there is a sequence $x_i\in K$ such that $x_i\notin A_i$. Since $K$ is compact there must be a subsequence $x_{i_n}$ converging to $x\in K\cap A_N$. Funny, but I cannot proceed because open sets seem too large and I can't catch all but finite of $x_i$ in a single $A_i$. I must be missing something simple.


If a sequence converges to some L, then the limit of the nth partial sum divided by n is also L.

Suppose $x_n \to L$, prove that $\frac{x_1 + \dots + x_n}{n} \to L$.  So far I've got that because $x_n \to L$, then for any $\epsilon>0$, there exists some $N \in \mathbb{N}$ such that $|x_n-L|< \epsilon$ whenever $n \geq \mathbb{N}$.  From this it's not hard to show that $|x_{N}+\dots + x_m - (m-N)L| < \epsilon$, but I don't know how to deal with the beginning of the series $x_1 + \dots + x_{N-1}$, which I need to ultimately show  $ |\frac{x_1+\dots+x_{N-1}}{n} + \frac{x_N + \dots + x_n}{n} - L|<\epsilon $ whenever $n \geq K$.


How do I travel with musical instruments?

How can I travel to another country (by plane) and take my instruments with me?  I live in Greece and I want to go to the USA with my double and electric bass.  I found  question, but it is limited to traveling in the states.


I'm trying to connect 32 I²C "root of trust"  devices.    I'm thinking about a good way that does that, I mean what kind of communication should I use? A digital multiplexer that selects a device? but based on what? switching on the VDD source? but that needs reinitialization of the device and that takes time.


How to set the Internet Explorer Home Page via GPO?

I need to set the default home page for the entire domain via GPO. Where is the IE Home Page Policy located?


How is javascript able to retain variable from a Promise?

I have a Javascript/Typescript code that looks like this:  for (let item of itemList) {   this.myService.myMethodReturningPromise(item.id).then(success => {     item.value = success;   }); }   By the time my Promise resolves, I have already exited the loop and I no longer have reference to item.  Why is it able to correctly set the value of each item in itemList?


Brightness is reset to maximum on every restart

The brightness of my laptop is reset to max on every restart. I tried the solution provided at  but had no luck.   This command   cat /sys/class/backlight/acpi_video0/max_brightness   Returns   cat: /sys/class/backlight/acpi_video0/max_brightness: No such file or directory   Then I found that I don't have a folder named acpi_video0, but a folder called intel_backlight:    Every time I increase or decrease the brightness using the brightness control keys, the values in brightness and actual_brightness get updated.  Is there any method I could follow to set the brightness to a fixed value on every boot and vary it as and when I need it using the brightness control keys?


The question is from Ahlfors Complex Analysis text.     Show that $\big|\frac{a-b}{1-\overline{a}b}\big|=1$, when either $|a|=1$ or $|b|=1$.   A solution I'm reading lets $|a|=1$ and $|b|\neq 1$.  then they show that $|a-b|=|1-\overline{a}b|$, by first squaring $|a-b|$ which gives $a\overline{a}+b\overline{b}-a\overline{b}-b\overline{a}=a\overline{a}+b\overline{b}-2Re(\overline{a}b)$.  My Question  I'm unsure of why $a\overline{b}+b\overline{a}=2Re(\overline{a}b)$?  They did write that this is because $b\overline{a}=\overline{\overline{a}b}$ but this didn't clear things up for me. Thanks


I just have a little question. Is there a possible way to write two chapters on the same page? Thank you for your help! : )  \documentclass[a4paper, 12pt, oneside, titlepage]{scrbook}  \begin{document}  \addcontentsline{toc}{chapter}{Abbildungsverzeichnis} \listoffigures\vfill \pagebreak \addcontentsline{toc}{chapter}{Tabellenverzeichnis} \listoftables\vfill  \end{document}


How is R used with ArcGIS for Desktop?   I have seen posts talking about combining rasters while using R.   I have not had much experience with R so not 100% certain of its capabilities.   I had thought that R was a scripting language for data analysis with tabulated data and data bases, but its seems much more than that.   Are there particular R libraries to incorporate it with ArcGIS for Desktop?


Am using the Funnelweb literate programming tool, producing Tex output.  In some code I have, I need to insert ASCII code 25 in the C source code.  This works fine as far as producing the C code, but when I run Latex on the .tex file, I get:  ! Text line contains an invalid character. l.1573 ... ^^Y   The relevant piece of the .tex file is:  \fwbtx[ ... ^Y ... ]   (in Emacs; the ^Y is one character, not two)  and the "fwbtx" macro is defined as:  \def\fwbtx[{% \begingroup% \def\par{\leavevmode\endgraf}% \catcode`\`=\active% \obeylines% \def\do##1{\catcode`##1=12 }\dospecials% \obeyspaces \parskip=0pt% \tt% \fwverbatimgobble}  \def\fwverbatimgobble#1]fwetx={#1\endgroup}   which, I believe, is supposed to escape all non-ASCII characters, so that Tex does not complain.  Can anybody explain what goes wrong?  Is there some simple work-around? Replace the "fwbtx" macro with something?  Any help appreciated.


Save *.deb files from var/cache/apt/archives folder for future installation

How can I store away the *.deb files from var/cache/apt/archives directory for future installation in case I need to reinstall the OS in ubuntu 11.10. I tried copying and saving  away but after OS reinstallation I tried reinstalling those deb files using "apt-get install file" but so many files were missed thought I copied everything. What am I missing, Please reply


Why does Apple allow factory reset if passcode is forgotten?

I just came across the instructions to factory reset Apple device if one does not remember the device passcode:   I am very new to Apple and I don't understand how come Apple allows such a thing. What if someone stole my device and wants to clean the device before selling it? Should the iTunes on the connected computer be logged in with the same Apple ID as the locked device? Is that what would prevent a thief from cleaning a stolen device? Would the above instructions work if the iCloud account on the device is locked as well?


Java pattern first letter should not be hyphens (-), apostrophes (‘), and spaces ( )

I am using this pattern to check   public static final Pattern VALID_FIRST_CHARACTERS = Pattern.compile("^[\\ \\'\\-]");  public boolean isValidFirstChar(String name) {     if (VALID_FIRST_CHARACTERS.matcher(name).matches()) {         return true;     }     return false; }   no luck, can somebody help me please ?


I need to convert a value which is in a DateTime variable into a varchar variable formatted as yyyy-mm-dd format (without time part). How do I do that?


Is "more quickly" grammatically correct?

Can you use "more quickly" in the following context?     I can move more quickly than she can.


I know this might be far fetched. In normal everyday life, we have huge amounts of data traveling through the air in the form of electromagnetic radiation. But what if instead of transmitter data through this channel we instead transmit low energy power. Where by at the receiver side we use the antenna or a custom built transducer that will be able to convert this transmitted power into a clean 5V DC voltage. Is this even feasible?


Integrating $ \int_0^1 \frac{x-1}{\ln x}\,dx. $

I need to compute $$ \int_0^1 \frac{x-1}{\ln x}\,dx. $$ Using the fact that $\frac{d(x^y)}{dy} = (\ln x)x^y$,   I can't get any clue.   Can someone give me a tip on how to better approach solving these kinds of problems?


I have these two SQL Server 2008 R2 queries:  SELECT COUNT(*) FROM OIS_NOA_Buffers WHERE geog.STIntersects(geography::Point(35.25934, -120.64432, 4326))=1; SELECT COUNT(*) FROM OIS_NOA_Buffers WHERE geom.STIntersects(geometry::Point(35.25934, -120.64432, 4326))=1;   The first returns a 1 and the second a 0. Both geog and geom are SRID 4326.  Geog geometry was derived from Set geog = Geom.STAsText()  Why wouldn't they both return 1?  (The point is under the polygons.)


Keyword location in URL permalink structure effect on SEO

I am in the process of a large rebuild and redesign of my real estate website. Through this process, I am expanding my content and number of internal pages which are structured as Wordpress custom post types with category archives. I am at a decision point with permalink structure for my site and can choose two different directions to go, not sure which is best or if there is any impact on SEO for the two options. Most of it comes down to location of keyword search terms being placed in the permalink structures.   Is there any difference in SEO power for the following keywords whether they are placed all at the end of the permalink, versus being distributed more throughout the entire link address depth when there is a hierarchy and some keywords are in the domain name, partly in the category name, sub category name, and partly in the post slug of the link?    Since I have one of the keywords in my main domain, is it redundant and not necessary to have it in the post slug ending as well?  Either way in terms of number of clicks or depth to get to the targeted page, it would be the same regardless of how the permalink is structured.  Which of these would be better for SEO? Keywords: grayhawk, scottsdale, arizona   Option 1 (category-subcategory-post slug):  dwellarizona.com/luxury/scottsdale/grayhawk Option 2 : dwellarizona.com/luxury/grayhawk-scottsdale-arizona


Can't assign script that takes control of mouse to shortcut

Background I have a small script that uses  to pick a color from the screen and paste it to the clipboard (). #!/bin/sh  color=$(xcolor) echo "$color" | xclip -sel clip notify-send "$color copied to the clipboard"  Problem The script works when invoked from the terminal. However, I have not been able to make it work as a keybinding. After setting a keybinding to the script (Settings > Devices > Keyboard), pressing it does not change the cursor to a color-picker as in the CLI command; it just finish automatically, sending the notification with $color as an empty variable. Technical details Ubuntu 18.04.4, GNOME 3.28.4, Kernel 5.3. Edit I set the Keybinding via GUI of Ubuntu Settings (in GNOME), Settings > Devices > Keyboard:  The script has execute permission; using bash /home/jorge/usrc/color-clip or dash /home/jorge/usrc/color-clip as Command produces the same wrong behavior.


Automatically refreshing a browser when a particular file in a directory changes?

Are there any add-ons that will cause a browser to automatically refresh a page when a particular file changes on disk?


Is it possible for a research article to be informative and ground breaking without referencing any other work?

This is a hypothetical question, but I am assuming that if there is a research field out there that has not been discovered, it will, in theory, be possible for an article to be written without containing any references.  The reason I ask this question is because I see that a good number of published articles seem to cite other works just to cite them and less often is it the case that the cited works add anything to the paper.


Why do credit card companies keep advertising balance transfers to those who don't carry a balance?

Given that credit card companies have access to your credit information, why do they keep advertising balance-transfer options to people who have great credit and never carry a balance?  What balance are these people supposed to transfer exactly? Why should they?


For any positive integer $n$, show that $x\gg 1 \rightarrow \log{x} < \sqrt[n]{x}$  I approached this problem by showing that $\lim_{x \to \infty} \frac{\log{x}}{\sqrt[n]{x}}= 0$  I tried to show that the limit converges to zero by showing that the integral test, $$\int_{1}^{\infty}{\log{x}\over\sqrt[n]{x}} dx $$ converges, which would in turn mean that the limit converges to zero (due to the $n^{\text{th}}$-term test)  But I can't get how to solve this improper integral, and also don't know whether my approach is right in the first place.


I want to make Beamer Template  similar to this . I have tried something like this. Now I need to customize the theme color ( I don't know which RGB combination will create something similar to the sample. Besides I need to remove one footer line (from my coding). Please suggest me some suggestion. Thank you  PS: the sample is a snapshot of a presentation. Please don't get confused with the alphabets.   \documentclass[11pt,a4paper]{beamer} \mode<presentation> \usepackage[utf8]{inputenc} \usepackage{default} \usepackage{hyperref} \usepackage{lmodern} \usepackage[english]{babel} \usepackage{amsmath} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{multimedia} \usepackage{epstopdf}  \usetheme{Berlin} \usecolortheme[rgb={0.0,0.0,0.4}]{structure} \useoutertheme{smoothbars} \useinnertheme{circles}


Eevee is broken (Don't know how to describe it)

Does anyone know what the heck is that? Eevee is just broken and I have no idea how to google that


The administrator has banned my IP address. What is problem

I am not a very experienced Ubuntu user, so I have to look up some information on the internet. Most of the links lead to . But each time I try to open a page on this site, it says "Sorry. The administrator has banned your IP address. To contact the administrator click here". That seems strange, because it is the first time I have ever been on ubuntuforums.org.  The worst thing is: when I click on the word "here" to contact the administrator, it says "The administrator may have required you to register before you can view this page." I tried logging in with SSO as it says, but when I open the login page, the message about my ban appears again.  I tried to contact the ForumCouncil from their page, but it gives me the same error => I can't open it  Is there any way to find out the reason why my IP was banned? Thank you.


What ratio of PhD graduates in STEM fields ultimately end up as (tenured) professors?

I recently saw this infogram circling around various social networks:    It appeared in  with the following claim:     Got a PhD? Your chance of becoming a Professor is 0.45%. Good luck.   Being a bit sceptical of the claim and of shiny info-grams in general, I traced the image back through  to  by the Royal Society (see page 14), featuring various reputable academics in the introduction. The report cites a number of other reports from UK organisations as its source (I did not dig deeper). The infogram seemingly pertains to graduates of PhDs in the UK in STEM fields.  I find the figures literally incredible. I cannot believe them. Fewer than 1-in-200 PhD graduates become professors? This would imply, for example, that STEM professors in the UK would need to graduate 200 PhD students just to "repopulate" themselves.  I would like to compare these estimates with figures sourced elsewhere. And so my question is:   Are any other studies or sources of data for estimating the number of PhD graduates who end up with professorships? (... preferably within the STEM areas and not restricted to the UK)    There is a related question specifically for the maths field and referring to tenure-track positions but none of the answers really address this question:   EDIT: Pointer to a follow-up question asked by @gerrit:


Why does Stack Overflow limits the number links per message to 2?

I like SO/SE, since I often find very good answers that are nowhere else. So, from time to time, when I encounter unanswered questions, I take the time to log-in and write a correct answer, in order to take my turn in helping those that do not know things that I know.  Today, I discovered that I cannot post more than 2 links in my answer, because my reputation is 0 (yes, I do not have time to help so often and people probably don't take the time to +1 my answers). However, the person was asking for some tools that can help solve his task and I had 3 tools to propose with 4 links to describe them. That's not what I call spamming... And that was the way to respond correctly to the question.  I don't have so much time to waste in logging-in and writing a correct answer... I overcome my dislikes and do so because I like to retaliate and help others when they help me. I'm sorry to say that, but if this limit stays, I'm off.  So my questions are: why this limit? Why so low?


Nominate for Reopening Shows Duplicate Message Boxes

When reviewing a question in the Reopen Votes queue, there are two main options: Leave Closed and Nominate for Reopening.  If I click Nominate for Reopening, a message box appears asking me if I am sure I want to vote to reopen:    If I click cancel, a second message box appears with the same question.   If I click cancel on the second message box is dismissed the message box, but nothing else happens.  If I click okay, a second message box appears with the same question.   If I click okay on the second message box is dismissed the message box, and a vote to reopen is cast. If I click cancel on the second message box is dismissed the message box, and a vote to reopen is cast.    I haven't yet exhausted all possible ways of interacting with these message boxes, but there is definitely at least one bug here.    A similar, and possibly related issue exists with the Leave Closed option. If I click Leave Closed, a message box appears asking me if I am sure I want to vote to reopen:    If I click cancel, the message box is dismissed, and my vote to leave closed is cast.  If I instead click okay the message box is dismissed, and my vote to leave closed is cast, but I occasionally see the error, "An error occurred when reviewing this item. Please try again."    Using Google Chrome Version 27.0.1453.116 m


Salutation for two doctors (not married)

Does use of the salutation     Dear Drs. Apple and Banana,   imply that Dr. Apple is married to Dr. Banana?  That is, would it be better form to use:     Dear Dr. Apple and Dr. Banana,   when Dr. Apple and Dr. Banana are unrelated, but happen to both be addressed in the same letter?


What happens to half of the energy in a circuit with a capacitor?

For a simple circuit with a battery supplying a voltage $V$ to a capacitor, let us assume that the charge on the capacitor is $Q$. Now, the work done by the battery or the energy supplied is given by the relation:  $$W=QV$$  But the energy stored in the capacitor is given by:  $$U = \tfrac12 QV$$  The value of $Q$ as well as that of $V$ should be the same in both the equations.  Now my question is, where is the other half of the energy that the battery supplied?


Can the boy escape the teacher for a regular $n$-gon?

This is related to   Suppose there is a boy in the center of a regular $n$-gon. The teacher is on the edge of the $n$-gon (but cannot leave the edge) and wants to capture the boy. At the beginning he is on a vertex. The teacher is $v(n)$ times faster than the boy. Which is the maximum $v(n)$ such that the boy can escape? (By escaping means he reaches the edge of the $n$-gon and the teacher is not there)  From the linked question we know $3 \le v(4) < 6$, and for $n= \infty$ (a circle) then I know a strategy such that $v(\infty) = \pi + 1$ suffice; I don't know if this is optimal. I also put convergence in the tags because my wild hypothesis is that the maximum $v(n)$ will converge to some value and it would be interesting to know which one!  Any cool way to solve this?


Let  f: Q → R be a uniformly continuous function. Show that there exists a uniformly continuous function g: R → R such that f (x) = g(x) for all x ∈ Q. My interpretation on this problem is that because Q is a subset of R, I need to construct from the original function f(x) a new function g(x) that is uniformly continuous and still maps x ∈ Q exactly like f(x). How do I go about this?


Let $f: [0,1] \rightarrow \mathbb{R} $ be continuous with $f(0) = f(1)$ *note, there is a part b*

(a) Show that there must exist $x,y \in [0,1] $ satisfying $|x-y| = \frac{1} {2}$ and $f(x) = f(y)$  I can start by defining a function $g(x) = f(x + \frac{1} {2}) - f(x)$ to guarantee an $x,y$ so that $|x-y| = \frac{1} {2}$ But how do I show that $f(x) = f(y)$?  (b) Show that for each $n \in \mathbb{N}$ $\exists x_n ,y_n \in [0,1]$ with $|x_n - y_n| = \frac{1} {n}$, and $f(x_n) = f(y_n)$  Actually I'm not sure where to start here. Any help is greatly appreciated. Thanks!


Where can I find the kernel configuration on each Linux distribution?

I'm pretty sure that all Red Hat and Debian based distributions follow the convention of shipping the kernel configuration in /boot/config-*, but what of other distributions?  Or, if this convention is extremely common, which distributions don't follow it?


Pros and cons of logistic regression with binary dependent and binary independent variables

What are the advantages and disadvantages of using logistic regression to represent the probability of a binary dependent variable Y, given that the independent variables x1, x2, ..., xn are also binary?


For all $n$, there are integers $x$, $y$, $z$ such that $x^2 + y^2 = z^n$

Prove that $\forall n \in \mathbb{N},$ there exist integers $x,y,z$ such that $x^2+y^2=z^n$.   I know that this is an induction proof, and I am assuming this needs to be broken up into cases where n is even and where n is odd.  But how do I even start doing this?


Infinitely number of primes in the form $4n+1$ proof

Question: Are there infinitely many primes of the form $4n+3$ and $4n+1$?  My attempt: Suppose the contrary that there exist finitely many primes of the form $4n+3$, say $k+1$ of them: $3,p_1,p_2,....,p_k$  Consider $N = 4p_1p_2p_3...p_k+3$, $N$ cannot be a prime of this form. So suppose that $N$=$q_1...q_r$, where $q_i∈P$  Claim: At least one of the $q_i$'s is of the form $4n+3$:  Proof for my claim: $N$ is odd $\Rightarrow q_1,...,q_r$ are odd $\Rightarrow q_i \equiv 1\ (\text{mod }4)$ or $q_i ≡ 3\ (\text{mod }4)$  If all $q_1,...q_r$ are of the form $4n+1$, then $(4n+1)(4m+1)=16nm+4n+4m+1 = 4(\cdots) +1$  Therefore, $N=q_1...q_r = 4m+1$. But $N=4p_1..p_k+3$, i.e. $N≡3\ (\text{mod }4)$, $N$ is congruent to $1\ \text{mod }4$ which is a contradiction.  Therefore, at least one of $q_i \equiv 3\ (\text{mod }4)$. Suppose $q_j\equiv 3\ (\text{mod }4)$  $\Rightarrow$ $q_j=p_i$ for some $1\leq i \leq k$ or $q_j =3$  If $q_j=p_i≠3$ then $q_j$ | $N = 4p_1...p_k + 3 \Rightarrow q_j=3$ Contradiction!  If $q_j=3$ ($\neq p_i$, $1\leq i \leq k$) then $q_j | N = 4 p_1...p_k + 3 \Rightarrow q_j=p_t$ for some $1 \leq i \leq k$ Contradiction!  In fact, there must be also infinitely many primes of the form $4n+1$ (according to my search), but the above method does not work for its proof. I could not understand why it does not work. Could you please show me?  Regards


Given a problem, how does one know whether to use quantum mechanics or classical mechanics?   Take for example electron scattering from a nucleus. The electrons are given a wavefunction in this case. Why not use the classical approach?


Object went missing when I press space (play animation)

There was little desk under those candles, and everytime I press play it dissapear. Same is with every object I copy, it just deletes. I tried unhidding everything but it doesn't appear. On the other hand, if I make new mesh, for example cube and play it doesn't delete. Also if I move something to other location and press play, it returns to the last location.


Is it safe to reuse unrefrigerated canola oil for deep frying?

Last night I deep fried some frozen chicken wings. After letting the oil cool, I filtered it through a cheese cloth and put it in a bottle. But I didn't refrigerate it. How long will it keep like this? Does it have to be refrigerated or frozen to be safe?


I want to make the origin in edit mode at a vertex, but it keeps setting it to the last clicked-on face :( So now in edit mode the pivot is on the last clicked-on face ;(


It would be great to create polls on Stack Exchange. For example:  What is your favorite programming language?  C C++ Java PHP ...   I think many people would use this.


How to salt PBKDF2, when generating both an AES key and a HMAC key for Encrypt then MAC?

When using Encrypt-then-MAC with AES and HMAC by password, and given 128 bits of payload with the ciphertext to store a random salt, which would be more secure:   Using PBKDF2 with then entire 128 bit random salt and generating 512 bits of derived data to split into a 256 bit AES Key and a 256 bit HMAC key.   or   Using PBKDF2 separately for each key using two 64 bits salts to generate a 256 bit AES Key and a 256 bit HMAC key.    or    Better option?


How do I connect to an SMB share requiring a user name and password?

I have a samba share on my LAN that requires a username and password to obtain write access (otherwise it defaults to read-only).  I can't figure out where in the Unity desktop I can connect to the share and be prompted for my login credentials.  I can mount the drive, of course, but then I'm browsing as a guest (read-only).  What gives?


Is there an in-game recipe book of all the recipes I have learned/discovered? Or do I need to write them all down?  I understand that there is no real structure to creating recipes (the only difference is status effects; or creating elixirs) but I was just wondering if there was any record that I can refer to in-game, because I would prefer it to just random concoctions each time.


I need to copy 50Gb info from 64Gb broken flash card. Sometimes I need to ask Windows 10 system to retry copy the same file for several times. How to achieve that?


Prove: If a linear map, $φ: U→V$  is bijective, then $φ(x)=0$ has only the solution $x=0$.  Either a proof or explanation will be appreciated.


Field name does not start with underscore - sonar issue

We are following Hungarian notation to declare private variables as below.  private IRepository<Request> _requestRepo;  public RequestService(IRepository<Request> requestRepo) {     _requestRepo = requestRepo; }   The above code shows a sonar issue like Field name does not start with underscore. Please tell me how to declare the private variables to satisfy coding standards?