I've requested the removal of one of my accounts on SE.  I've received the mail "your accout has been scheduled for removal (...) your accout will be automatically deleted within 24 hours".  However, 3 days has passed, and that account is still on my account list.  Have I done or understood anything wrong?

I have 3 accounts that I am deleting - however, several hours after the 24 hour (+ grace period - end about 4-5 hours ago), the countdown completed, but disappeared and the accounts are still there.   I would rather not go through another 24 hours, and would like to have these accounts deleted (and yes, I have thought about it and this decision is not up for discussion).  Currently, the accounts are still there.  Could this please be seen to?


I have used aluminum foil when I grill salmon because it keeps the oil from running onto the heating element and smoking the fish.  Can anyone suggest a substitute for aluminum foil?

Is there a replacement that can be used for aluminum foil in the oven?    I don't want to foil in my kitchen. Is there an alternative which can be used in the same way as aluminum foil, but has no risk of transferring aluminum to the food?   For example, what can I use to cover a meatloaf when baking it in the oven? Or in a slow cooker?


About an hour ago I received a series of upvotes. All on different, unrelated questions and answers, all within a few minutes window. This obviously raised a red flag.  Should I do anything with this or just wait for Community user to sort it out?

I just noticed that I lost a bunch of points from my reputation score, and I used the "reputation" tab on my user profile page to try and track down the cause.  During my investigation, I noticed there was an unusual event of type "reversal". In the normal place of a question title, it says "voting corrected".     What does this mean, and what caused it?  Did I do something wrong? Why did I lose all of that reputation? Is the system punishing me for leaving too many good answers?  Is there any way to earn it back?


According to Euclidean lemma it is defined that if $p$ is prime then $$p|ab\Rightarrow p|a\lor p|b$$ How to prove by descending induction that if $$p|a^n \Rightarrow p|a $$  knowing that $a^n = a \times a^{n-1}$  If there is an easier solution don't hesitate to post

I have this exercise in my worksheet in the discrete mathematics course.I don't understand the part that deals with prime numbers in .     "Show that for a prime number $p$, if a $p\mid a^n$ then $p\mid a$"    Can somebody show how ?


I would be grateful for any comments regarding two variations of Schrödinger's Cat experiment I’ve been pondering.  In the first, wishing no harm to the animal, I remove the cat and replace it with a very simple clock.  The clock could be mechanical, chemical or atomic in nature, and is just the simplest way to measure time after an event occurs.  It is totally enclosed within the box and will start when the radioactive decay event is detected.  Sometime after the experiment begin I look into the box.  Sometimes I would expect to see the clock had not been activated but other times it has.  In those cases, what will the clock show?  Common sense (AKA classical phyiscs) would say it would show an apparent random value but, if I repeated the experiment enough time, I would see it was related to the probability the radioactive substance has decayed.  What I would not expect is the clock to consistently showing that it started only when I looked inside the box.  If the quantum state only collapses when I look, how come the clock might say it started minutes ago?  EDIT: I am particularly interested in the apparent paradox of an event triggering an event in the past. How, in quantum terms, would this be explained?  Variation 2 is also simple but a bit more dramatic.  Here the cat is replaced with a (very small) explosive device – just enough to blow the box part.  If I never look inside the box and hence the quantum state is never observed, does the box never explode?  If it does explode before I look inside, why?  And if, after a long time, the box has not explored and I then look inside, does this mean it’s very like the box will exploded at that moment and I get my hair singed!  Your thoughts please. Bryan.

In the Schrödinger's cat experiment 'there is a tiny bit of radioactive substance, so small that perhaps in the course of the hour, one of the atoms decays'. The rest of the experiment magnifies this into a macroscopic superposition, but I want to know more about the claim that the radioactive decay produces a superposition.  Firstly, has this been experimentally tested? Something along the lines of accelerating radioactive ions so there is a chance that they will decay while in flight (and so change trajectory), and then combining the decayed and undecayed parts to look for interference.  Secondly, the tiny bit of radioactive substance will still contain large numbers of atoms.  Won't this cause problems?  If the atoms were in a Bose-Einstein condensate, then I would expect that there could be a superposition of 'one (unspecified) atom decayed' and 'no atoms decayed', but they're not, so a specific atom will decay.  Won't that mess things up?


I've tried SharpKey, but it doesn't recognize, and KeyMapper, but it seems to have no effect at all; not sure why. How can I make Caps Lock behave like Alt GR?

Does anyone know how to remap Caps Lock to AltGr/Alt+Ctrl on Windows 7?  Closest I've come to solving it is using SharkKeys, but if I try to map anything with AltGr it says SharpKeys doesn't know about the key.  Here's the old bug report about it:   I've been searching a lot, but all the registry hacks are how to map it to Shift or Ctrl, nothing about AltGr.


Is there any difference in effects from time dilation of that due to gravity vs. that due to velocity?

There are two kinds of time dilation:   One because the other clock moves fast relative to me (special relativity). Another one because the other clock is in a stronger gravitational field (general relativity), or accelerating rapidly (equivalence principle).   So are these two effects are totally independent? Is it possible to derive the general relativity case from the special relativity case?


I can't seem to be able to type in a password so that I may acquire access to #apt-get. I'm looking to update my system via terminal, but typing out my password does no good to get me into su, as the spaces stay blank, and what I know is the password won't go through. Has anyone else had this issue?

When I'm about to install a program in the terminal it wants the password:  [sudo] password for xxx:   But when I start to type my password nothing happens. What should I do?


Show that $f(x,y) = \frac{xy^2}{x^2+y^2}$ (where $(x,y) \neq0$, and $f(0,0) = 0$) is continuous but not differentiable at $(0,0)$.   I have shown continuity but am stuck on differentiability. I cannot seem to find a way in my text to show that the above is not differentiable.  Thanks

Show that $f(x,y)=\dfrac{xy^2}{x^2+y^2}$ (with $(x,y)\not=(0,0)$ and $f(0,0)=0$) is continuous but not differentiable at $(0,0)$.  I tried to show continuity with an $\epsilon -\delta$ argument but I don't know how to factorize the expression so that I can have something useful.   For differentiability I think I should show that the partials are not continuous at $(0,0)$. But finding the partials is also painful.


Though this is a small question to ask, wanted to understand this strange behavior! Following is the code and the behavior of the code that's in discussion (through the console output).  public class EmptyBracesWithinClass {     public static void main(String[] args) {         EmptyBraces eb = new EmptyBraces();         System.out.println("SYSO within main() method");     } }  class EmptyBraces {     {         System.out.println("SYSO within empty braces");     }      public EmptyBraces() {         System.out.println("SYSO within constructor() method");     } }   Console output:  SYSO within empty braces SYSO within constructor() method SYSO within main() method   The question here is, why would the piece of code within the empty braces get executed first during the object instance creation of EmptyBraces class (though it is never declared as STATIC explicitly)?

My question is about one particular usage of static keyword. It is possible to use static keyword to cover a code block within a class which does not belong to any function. For example following code compiles:  public class Test {     private static final int a;         static {         a = 5;         doSomething(a);     }     private static int doSomething(int x) {         return (x+5);     } }   If you remove the static keyword it complains because the variable a is final. However it is possible to remove both final and static keywords and make it compile.   It is confusing for me in both ways. How am I supposed to have a code section that does not belong to any method? How is it possible to invoke it? In general, what is the purpose of this usage? Or better, where can I find documentation about this?


I am a beginner in these stack-like communities. I have posted my  on Stack Security, and people marked it as "on hold," for being "unclear what you're asking."  I have seen the error and fixed it. But, I have a big question: Is "on hold" the same as being blocked question? Can somebody answer the question now? The moderator has not removed the on-hold tag.  I have edited it. I think that it is right, now. But the on-hold tag still there.  Can I delete it and post a new question? Must I wait for a moderator reply?

Questions can be closed or marked as duplicates.  What does it mean for a question to be "closed"? What does it mean for a question to be marked as a "duplicate"? Who can close a question? What are the reasons for closing a question ? Is closure the end of the road for a question? When are closed questions eligible for deletion?   Related        For more information, see "" in the .


obj.get(childFieldAPIName).addError('Required');   Error:      Method does not exist or incorrect signature: void get(String) from the type Object   I am trying to add the error on the fields which are in String format "childFieldAPIName" but it is not allowing.  Something like this          genericObj.get('fieldname').addError('myString');

Is there a way to add an error on a dynamically referenced field? Let's take this simple example:  opp.get('Name').addError('Invalid name');   This is not working, I'm looking for a similar minded way.  Thanks


I have a sentence below:     You ain't gotta believe me.   In this sentence, If i'm not wrong, Does ain't mean have not? and Does gotta mean got to?  So, it means You have not got to believe me. I'm I correct?

As far as I understand, "ain't" can mean either "isn't" (ain't no sunshine) or "hasn't" (you ain't seen nothing yet).  Are there any rules when "ain't" is used? Does it have a different meaning than "isn't" or "hasn't"?  Edit: Maybe asking for rules was not the best idea. A better question would have been: when do you use "ain't" instead of "isn't"/"hasn't"?


If $h: \mathbb{C} \rightarrow \mathbb{C}$ is a one-to-one holomorphic map, then $h(z)=az+b$,  where $a,b\in\mathbb{C}$.  How to prove this argument?

Can we prove that every entire one-to-one function is linear?


a cyclist travels 30 km in one hour  1) Demonstrate that there is an interval of 10 minutes such that the cyclist has traveled 5 Km  2) Is there always a time interval of 40 minutes during which he will have traveled 20 Km?  for the first question, that's what I did : Note f the function that represents the distance traveled by the cyclist as a function of time (expressed in minutes). $f$ is a continuous function, $f (0) = 0$ and $f (60) = 30$. We want to prove that there is a time interval of 10 minutes such that the cyclist has traveled 5 km. In other words, we want to find $x \in [0,50]$ such that $f (x + 10) -f (x) = 5$.  Suppose that such an  $x$ does not exist. By the intermediate value theorem, we know that: or else,   $\forall x∈ [0,50]$, we have $f(x + 10) -f (x)> 5$.  or, $\forall x∈ [0,50]$, we have $f (x + 10) -f (x) <5$.  In the first case, we have $f (60) =  f (60) -f (50) + f (50) -f (40) + f (40) -f (30) + f (30) -f (20) + f (20 ) -f (10) + f (10)-f(0) > 6 × 5=30$. which is a contradiction. In the second case, we would find $f (60) <30$, which is also a contradiction. The hypothesis formulated is therefore false: there exists $x∈ [0,50]$ such that $f (x + 10) -f (x) = 5$.  For the second question,I Think that the answer in No but i don't know how to prove it .  Do you have any suggestions ?

Let $f \in C[0,1]$ and $f(0)=f(1)$.   How do we prove $\exists a \in [0,1/2]$ such that $f(a)=f(a+1/2)$?  In fact, for every positive integer $n$, there is some $a$, such that $f(a) = f(a+\frac{1}{n})$.  For any other non-zero real $r$ (i.e not of the form $\frac{1}{n}$), there is a continuous function $f \in C[0,1]$, such that $f(0) = f(1)$ and $f(a) \neq f(a+r)$ for any $a$.  This is called the Universal Chord Theorem and is due to Paul Levy.  Note: the accepted answer answers only the first question, so please read the other answers too, and also this answer by Arturo to a different question:     This is being repurposed in an effort to cut down on duplicates, see here: .  and here: .


so I need to use a template class as a container, so I need to create a new associative container that's derived from STL set, so far this is what I have (Code Snippets from relevant parts).  In UpdatableSet.h  #include <set>  template <class T> class UpdatableSet : public std::set<T> { public:     UpdatableSet(){};     ~UpdatableSet(){};     bool add(T); private:     std::set<T> set; };   add(T), this method is supposed to add the T to the set and if it was successful, return true, or return false, not sure if this is correct or not, because I don't fully understand the concepts.  template <class T> bool UpdatableSet<T>::add(T update) {      if(set.insert(update).good())     {         return true;     }     else          return false;  }   in main  UpdatableSet<CDAlbum> updatableAlbumSet; //Want this to be a set of objects of the CDAlbum kind updatableAlbumSet.add(theCDAlbum); //how do I use this to add to the set?   Ultimately I'm getting this compilation error  symbol                             in file bool UpdatableSet::add(CDAlbum) task2Main.o ld: fatal: symbol referencing errors. No output written to a.out  EDIT: So you guys were right, I've figured out that I've needed to create the methods myself instead of deriving it from set.  here's how it looks now  in UpdatableSet.h  template <class T> class UpdatableSet {        public:     UpdatableSet(){};     ~UpdatableSet(){};     bool add(T);     int size();     int begin();     int end();     typedef typename set<T>::iterator iterator;      private:     std::set<T> set;  };  template <class T> bool UpdatableSet<T>::add(T update) {     return set.insert(update).second; }  template <class T> int UpdatableSet<T>::size() {     return set.size(); }  template <class T> int UpdatableSet<T>::begin() {     return set.begin(); }  template <class T> int UpdatableSet<T>::end() {     return set.end(); }   However I'm getting this error now "task2Main.cpp", line 67: Error: Cannot use int to initialize __rwstd::__rb_tree, std::less, std::allocator>::const_iterator.  "task2Main.cpp", line 67: Error: The operation "__rwstd::__rb_tree, std::less, std::allocator>::const_iterator != int" is illegal.

Quote from :     The only portable way of using templates at the moment is to implement them in header files by using inline functions.   Why is this?  (Clarification: header files are not the only portable solution. But they are the most convenient portable solution.)


Show that $\binom{p^a-1}{k}\equiv(-1)^k\pmod{p}$ for $0\le k\le p^{a}-1$.   Solution: $\binom{p^a-1}{k}=\frac{(p^a-1)(p^a-2)\cdots(p^a-k)}{k!}$.       Idea: Then power of $p$ in $k!$ must be less than the power of $p$ in Numerator.          ----(**)  Then i can directly write  $p^a-1\equiv-1\pmod{p}$,$p^a-2\equiv-2\pmod{p}\cdots$ and $p^a-k\equiv-k\pmod{p}$.  Then, we have: $\binom{p^a-1}{k}\equiv(-1)^k\pmod{p}$.  Is my idea correct? If yes, how should I proceed to prove (**) statement.   Thanks in advance.

Proof that if $p$ is a prime odd and $k$ is a integer such that $1≤k≤p-1$ , then the binomial coefficient  $$\displaystyle \binom{p-1}{k}\equiv (-1)^k \mod p$$  This exercise was on a test and I could not do!!


I submitted my article to a SAGE journal roughly six weeks ago. The status of the submission was "awaiting reviewer scores" for four weeks and few days ago it changed to "submitted". Any idea what this means? Does it mean that the article is with the editor who goes through the reviewer comments? Or does it mean that the article has been sent for new reviewers? I have also checked the typical workflow of the journal, but was not able to find similar situation.

What steps does a manuscript typically go through from submission to publication (or rejection) in a typical journal? How are these steps referred to, in particular by editorial systems, and how long do they each typically take?  Note that this question is about the typical situation and hence not about:   Journals with an atypical workflow, e.g. those that allow for an instantaneous reviewer–author interaction. Exceptional steps or rare occurrences such as withdrawal or .   This is a canonical question on this topic as per . Due to its nature, it is rather broad and not exemplary for a regular question on this site. Please feel free to improve this question.


My current setup is nginx as a load balancer, in front of a bunch of upstream servers.  I want to be able to deploy with no change in user experience. This means no 502s and no increase page times.  My understanding is that when nginx -s reload is issued, nginx will gracefully spawn new threads to handle new connections for the new configuration, but will still finish handling requests that were in-flight at the time of reload. Moreover, I have read somewhere that marking an upstream as down in the upstream block, and reloading, will take that upstream from the rotation, but will still finish any in-flight connections to it.  Is any/all of this correct?  The current plan is to have a small process in the nginx host, that will basically mutate nginx configuration and issue these graceful reloads when asked to do so through an internal REST API.  My deployment tool will then connect that process and add/remove my upstreams from nginx config in sequence, after graceful shutdown and boot up/warm-up for each upstream is complete.  Does this make sense? How are other people doing this? Are there any already available tools for this?  I haven't had a lot of luck searching for info on this...

Apache has a graceful option which can scan for modification in http.conf without restarting Apache. What about nginx?


When an answer consisting solely of a link to elsewhere in the Stack Exchange universe is posted, it should be converted to a comment prefixed with "See: ".  Perhaps this could be widened to cover any single-link answer.  Some sort of rubric, perhaps     Your answer consists solely of a   hyperlink, and will be posted as a   comment unless you add further   details.   could appear when the answer is being composed.

I posted an answer (pointing to another question already asked) but when I hit submit, I saw my answer appear as a comment to the question instead.   I tried it a couple of times and still the same result. The answer gets eaten up and is transformed into a comment.   Is this a bug?


I want to dual boot Win10 and Ubuntu 16.04. I'm using a Dell Inspiron 5565 AMD (not Intel) laptop with touchscreen Radeon graphics 4GB. Preinstalled OS is Windows 10 home.  I've created unallocated space and fixed fast boot settings. I tried thumb drives and DVD with a fresh Ubuntu iso each time.   The installation process is freezing on the splash screen.   Does this message give any useful clues?  CPU: 0 PID:33 Comm: kworker/0:1 Tainted G D L 4.10.0-28 ...

I am trying to boot Ubuntu on my computer.  When I boot Ubuntu, it boots to a black screen.  How can I fix this? Table of Contents:


I have an EOS 60D that has had intermittent focusing issues since a purchased it. I primarily use the Canon 28-135mm f/3.5-5.6 IS kit lens.  I also have a new Canon 70-300mm f/4-5.6 IS USM and a Tamron 70-300mm f/4-5.6 Tele-Macro.    I can no longer use any of these lenses as the focus is completely soft.  I tried all modes of auto focus on each lens as well as both extremes of aperture and mid range aperture settings.  I used manual focus and live view mode.  I tried the range of focal length zooms and all to no avail.    This is the second Canon camera that started doing the same thing, the other is an EOS 40D.  Both cameras worked perfectly when purchased, and slowly failed over time.    I just talked to customer service at Canon and he told me three things.      Canon MAY stop supporting the 60D on June 30, 2019.  which means that  will no longer be able to get my camera repaired by Canon. He said that when I use a third party lens on my Canon camera it can cause something in the camera itself to go out of adjustment or fail requiring repair of the camera. There is a flat labor rate at Canon of $200.  Parts, tax and shipping are extra.  I feel that this repair will cost in the neighborhood of $300.  But this is a one time shot if they are going to stop supporting this camera at the end of June.    So my question is does anyone else have experience with a 60D specifically or any camera with auto focus failing like this, and does what I was told about the lens damaging the camera make any sense?  Also, is it time to buy a new Canon?  Or should I sell all of my gear and switch to Nikon?

Probably a novice question, but how do I correctly diagnose from a photo for what reason that camera wasn't able to focus properly?  It can be any 1 of the following   Unsteady hand Lens issue Metering Re-Calibration required in camera or ...   Is there a set of unsaid protocols that needs to be followed by a photographer?  Goal is to get a sharp and crisp image prior to editing.  [PS: I own a Nikon D5200.]


I would think pressure cooking chicken breasts in the instant pot for longer, and by that I mean 12 minutes or a little more, they would come out super tender. Am I wrong? Would the opposite happen? I may try it as an experiment.

Just cooked some chicken breasts today. All day in the crockpot and when done the meat was horribly dry.  I put chopped onions, carrots, spices, and coconut milk and 1/2 cup water and 4 chicken breasts.  There was plenty of fluid there when it was done, but the cooked chicken meat was really dry.  This seems to happen with beef roast as well.  Is there some trick to getting meat to be tender when cooking in the crockpot?


I have a doubt what is 4'd0 meaning in this program? // Johnson Counter  module johnson_counter( out,reset,clk); input clk,reset; output [3:0] out;  reg [3:0] q;   always @(posedge clk) begin     if(reset)        q=4'd0;     else     begin          q[3]<=q[2];         q[2]<=q[1];         q[1]<=q[0];         q[0]<=(~q[3]);     end end  endmodule

I see syntax quit similar to this very frequently:  4'd0  Sometimes it is associated with an assign statement:  assign S0 = 2'b00;  I tried searching online however I could not find any sources.


As shown at diagram, how can I execute sample function in the x application?

Basically, I have an iframe embedded in a page and the iframe has some  routines I need to invoke from the parent page.  Now the opposite is quite simple as you only need to call parent.functionName(), but unfortunately, I need exactly the opposite of that.  Please note that my problem is not changing the source  of the iframe, but invoking a function defined in the iframe.


So I have been using Ubuntu for a few months now, and have come across a very noob terminal question.  I want to go from home -> Documents -> My Programs  I am able to get into my documents folder by doing  cd ./Documents   But when I want to go into "My Programs", I am unable to do so because of the space between "My" and "Programs". Is there a different syntax I must use to access this folder via terminal?

I want to enter the following folder in the terminal:  Milano, Torino (Jan)-Compressed   How should I write the command cd to enter this directory?  Spaces and several other special characters like \, *, ), ( and ? cause problems when I try to use them in the command line or scripts, e.g.:    $ cd space dir bash: cd: space: No such file or directory  $ cat space file cat: space: No such file or directory cat: file: No such file or directory  $ cat ( bash: syntax error near unexpected token `newline'  $ echo content >\ > ^C  $ ls ? (  )  *  ?  \   How do I enter file or directory names that contain special characters in the terminal in general?


I'm trying to add sample code to my document. It seems that the listing is left aligned with the margin, and the numbers go outside it. How should I align the number, instead of the code? Here is my latex code:  \documentclass[a4paper,10pt]{article} \usepackage[utf8x]{inputenc} \usepackage{listings}  %opening \title{} \author{}  \begin{document} Some dummy text. Some dummy text. Some dummy text. Some dummy text. \begin{figure} \begin{minipage}[b]{0.4\linewidth} \begin{lstlisting}[language=C, %frame=single, basicstyle=\footnotesize\ttfamily, numbers=left,stepnumber=1, morekeywords={assert} ] void test(int x, int y){   if(x > 5){     x++;     if (x < 3)        x--;     else        y = x;   }   assert (x < 10 ); } \end{lstlisting} \caption{A simple example} \end{minipage}  %another minipage goes here  \end{figure}  \end{document}   Thank you.

I use the listings package for code listings and I turned the line numbers on. But they appear left of the paragraph. I want them inside the paragraph. In the documentation it looks just right. Here is my code:  \documentclass[12pt,a4paper]{scrartcl} \usepackage{listings} \lstset{numbers=left} \begin{document} \section{Test} Test \begin{lstlisting}     test() \end{lstlisting} \end{document}


I've had a look on the website but nothing seems to answer the particular question I have.   (i) Let F be a finite set. Show that any injective (that is, one-to-one) map ψ : F → F is surjective (that is, onto).  (ii) (Paradox of Galileo) Give an example of an injective map ϕ : N → N that is not surjective.  (iii) Now let T be a countably infinite set. Deduce that T can be put in one-to-one correspondence with some proper subset of itself; so that there exists an injective map φ : T → T that is not surjective.  (iv) Let S be an infinite set. Show that there exists a countably infinite subset T of S.  (v) Deduce from (i), (iii) and (iv) the Dedekind-Pierce Theorem: A set S is infinite, if and only if S can be put into one-to-one correspondence with some proper subset of itself.  All the other parts of the question are fine, but i don't understand how to do part V. How do I use the other parts of the question to derive this fact.   Help is much appreciated always.   Thanks

Maxwell Rosenlicht claims in "Introduction to analysis" that a set is infinite if and only if it may be placed into one-to-one correspondence with a proper subset of itself.  He says this is self-evident because a finite set cannot be placed into a one-to-one correspondence with a proper subset of itself (because it has fewer elements), and whilst this is reasonable - I cannot follow Rosenlicht in that "the above therefore follows obviously". Why must a set be infinite just because of some property of finite sets?


I just obtained a small computer from ASUS with Ubuntu pre-installed. The scrolling, video, and animations are sluggish and choppy, though. The Details from All Settings states that the driver in use is "Gallium 0.4 on llvmpipe (LLVM 0x300)". However, the Additional Drivers claims that the driver in use is "drm driver for the Intel GMA500". I think that the computer is using the wrong driver, which could account for the choppiness in the scrolling and video. How can I correct this?  Computer Specs: 2GB RAM, 4x1.86GHz Intel Atom Processor, Intel GMA 3650 GPU

I am looking for instructions on how to install cedarview graphics drivers on Ubuntu 13.04 32bit.  My graphics hardware is a GMA3600 aka Power VR SGX545.  EDIT: It seems that they are not in Raring yet, but only Precise:   EDIT2: they seem to be closed source.


I co ordinates stored as an object and have duplicated the data so i have a copy before the co ordinates change. But the problem is, when I change the co ordinates both copies change to the new version and I lose the original.  So i create it like this:  myObj          = {}; myObj.position = {'x':12,'y':24}; myObj.startPos = myObj.position;   So if i change myObj.position, I don't want myObj.startPos to change. What is the simplest way to prevent this from occurring?

What is the most efficient way to clone a JavaScript object? I've seen obj = eval(uneval(o)); being used, but . I've done things like obj = JSON.parse(JSON.stringify(o)); but question the efficiency.  I've also seen recursive copying functions with various flaws.  I'm surprised no canonical solution exists.


I read this sci-fi book back around 1987 that my father had finished.  My memory of the book is sadly very limited, but the emotion of enjoying it string prompting me to try and remember it.  My clear memories are it is set in a spaceship, there is a crew (or team) that might have been space pirates or thieves of some sort. The encounter an alien of some type that I believe was described as spider-like with ultrathin (practically invisible to the human eye) legs that could slice through the members of the crew.

I recall reading a book where the nondescript quirky captain of an independent starship was hired to take a group to a possible lost starship. The ship was a giant ecological repository and contained tech which had since been lost. Everyone tried to board, running afoul of various creatures and defenses. The independent captain (thought least likely to survive) wound up somehow managing to become recognized by the ecological ship as its new captain-owner, and spent the rest of the book providing its services, on his terms.  Part of this story also appears as a short story in an Analog magazine.  I probably read this in the late 80s, early 90s.


I downloaded Eclipse Juno package, and extracted it to /opt directory. For installing it, I followed the steps given in this site -  under the User Installation section. I created the opt_eclipse.desktop file in /usr/share/applications/ directory. Here is the content of my desktop file:  [Desktop Entry] Type=Application Name=Eclipse Comment=Eclipse Integrated Development Environment Icon=eclipse Exec=eclipse42 Terminal=false Categories=Development;IDE;Java; StartupWMClass=Eclipse X-Desktop-File-Install-Version=0.20   Then I installed the desktop file on Unity using the following command, as given in :  sudo desktop-file-install /usr/share/applications/opt_eclipse.desktop   Then I created the symbolic link using the below command:  sudo ln -s /opt/eclipse/eclipse /usr/local/bin/eclipse42   I also moved the icon to the pixmaps folder using the below command:  cp opt/eclipse/icon.xpm /usr/share/pixmaps/eclipse.xpm   Now, when I go to Unity, I can find the Eclipse Icon. But, when I click it, nothing happens. It doesn't get started. I'm completely new to Ubuntu. Did I miss something out there?

How can I pin eclipse indigo 3.7 I have 'installed' at /opt/ to the taskbar?  I have tried launching eclipse and right-clicking to choose the 'keep in launcher' option. But when I click that icon, after closing eclipse, it doesn't start eclipse.  I have already looked at  but no answer worked for me. (Mod note: The answers from this thread are now merged into this one)


I want to proove that 2 and 3 divide $x^3 - x, x \in \mathbb{N}$ and I'm stuck at the inductive step, here's where I'm at: For all $x \in \mathbb{N}$, let $P(x)$ be the  proposition: 2 and 3 divide $x^3 - x$ Basic step: the first term in $\mathbb{N}$ is $0$, then: $\frac{0^3 - 0}{2} = 0$ et $\frac{0^3 - 0}{3} = 0$, thus $P(0)$ is true. Inductive step: For the inductive hypothesis, we assume that $P(k)$ is true for an arbitrary nonnegative integer k bigger than 0. That is, we assume that 2 and 3 divide $k^3 - k$ To carry out the inductive step using this assumption, we must show that when we assume that $P(k)$ is true, then $P(k + 1)$ is also true. That is, we must show that 2 and 3 divide $(k+1)^3 - (k+1)$ Is the next step here is that we need to prove that $\frac{(k+1)^3-(k+1)}{2}$ and $\frac{(k+1)^3-(k+1)}{3}$ are integers? thus 2 and 3 divide $(k+1)^3 - (k+1)$?

As homework, I have to prove that     $\forall n \in \mathbb{N}: n^3-n$ is divisible by 6   I used induction  1) basis: $A(0): 0^3-0 = 6x$ , $x \in \mathbb{N}_0$ // the 6x states that the result is a multiple of 6, right?  2) requirement: $A(n):n^3-n=6x$  3) statement: $A(n+1): (n+1)^3-(n+1)=6x$  4) step: $n^3-n+(n+1)^3-n=6x+(n+1)^3-n$  So when I resolve that I do get the equation: $n^3-n=6x$ so the statement is true for $\forall n \in \mathbb{N}$  Did I do something wrong or is it that simple?


I am trying to fetch one file from two different paths.I used below command, seems execution fine but there is no output.  find . \( -path "/usr/local" -o -path "/user/local/archive" \) -name "xyz.csv"   Could you please help me on this?

I am trying to list all the files from dir1, dir2, dir3 and dir4 which might be anywhere in as a sub directory of my cwd using the find command. I tried the following with no success:  find . -type f -regextype posix-egrep -regex 'dir1/.+|dir2/.+|dir3/.+|dir4/.+'   I tried posix-extended as well. How can I list these files?


I'm using blender as a video editor, everything is setup correctly for what I normally do.  I capture game footage with Open Broadcasting Software and upload the odd video here and there.  Blender seems awesome in almost every way but I recently switched to using Nvidia ShadowPlay to record my gameplay footage as the quality is fantastic at high bitrates with almost no penalty to performance.  The problem I have is that when I try to edit a video in Blender the audio and video tracks are out of sync.  When I view the video information in VNC while playing the raw recording the frame rate is never the same.  Each video has a slightly different frame rate.  I have the frame rate set to 60fps.  However the actual videos come out as 59.8842fps or 59.245fps.  I think this is what is causing the audio and video to be out of sync in Blender maybe?  I can input a custom frame rate but it looks like it only allows certain increments such as 59 or 59.4, or 60.  Is there any way to get these tracks to sync up so I can simple cut out the parts I don't want?  Any help would be greatly appreciated.

I'm using Blender 2.77.  When I import footage into the VSE with the correct frame rate (23.98fps) every single audio strip is 2 frames longer than the corresponding video clip.  I think the problem is that my recordings are actually 23.97fps.  The issue with that is that when using the custom fps setting there are not enough decimal places to input a value that will result in a frame rate of 23.97 (i.e. 1.0015).  I'm not positive this will fix it but I think it should.  Does anyone else have any ideas or experience with this issue?


Swarf is a word for metal particles or debris produced in polishing metal with abrasive tools. For example, swarf can be produced when polishing teppanyaki grill or sharpening knives.  I often see Kebab sellers who don't wipe their knives after sharpening and cut cooked meat.  Teppanyaki grills are often polished but without washing them thoroughly. Without any doubt many people still consume such contaminated food as if it is safe.  Is it safe to eat food contaminated with swarf? Is there any scientific article that support the conclusion?

I've been wondering about this for a while, since getting interested in knife sharpening.  When using a knife, it will get duller. One (the primary) reason being that you "bend" the edge. You fix this using a honing steel.  After a while though, you need to sharpen the knife again.  Another setting: If you have a brittle knife and/or mistreat your knife you will chip it.   As far as I can tell, this should mean that small pieces of metal (dust, shavings, etc.) come lose, and then likely get in the food.  Is this correct? Are there no health considerations when digesting small pieces of very sharp metal?


I have watched and read a lot on the topic of General Relativity and the geometry behind it. I am confident that I can derive an approximation of the the stress-energy-momentum tensor with just the metric tensor, but if I was given the stress-energy-momentum tensor I'm not sure how I would go back to find the metric. How can I use  to find the metric tensor? Would I have to expand all of the notation? Or is there some equation I can plug into my computer to get it? Or is there some other way?

I have have set my self a challenge to learn all the maths behind the Einstein field equation (EFE), and from reading it seems that the Metric tensor is the thing we are trying to find (from the 10 equations that forms the EFE). but since nearly all the terms in it are functions of this metric tensor, this seems very hard. What type of maths do we use to do this? (I have copied and pasted the EFE just for reference):  $$R_{\mu \nu}-\frac{1}{2}g_{\mu \nu}R+g_{\mu\nu}\Lambda=\frac{8 \pi G}{c^4}T_{\mu \nu}$$  Edit: Thanks for your comments. Just as I have no one else to ask, is this the equation that we try to solve:  $$\left(\frac{\partial}{\partial x^{\lambda}}\Gamma^{\lambda}_{\mu \nu}- \frac{\partial}{\partial x^{\nu}}\Gamma^{\lambda}_{\lambda \mu}+\Gamma^{\lambda}_{\lambda \rho}\Gamma^{\rho}_{\nu \mu}-\Gamma^{\lambda}_{\nu \rho}\Gamma^{\rho}_{\lambda \mu}\right)-\frac{1}{2}g_{\mu \nu}g^{ab}\left(\Gamma^c_{\enspace ab,c}-\Gamma^c_{\enspace ac,b}+\Gamma^d_{\enspace ab}\Gamma^c_{\enspace cd}-\Gamma^d_{\enspace ac}\Gamma^c_{\enspace bd} \right)+g_{\mu \nu}\Lambda=\frac{8 \pi G}{c^4}T_{\mu \nu}$$  with the $R_{μν}$ and $R$ terms expanded and where $g_{μν}$ and $T_{μν}$ are the μν th components from the related tensors? (a yes or no answer will be fine, thanks).


Are electrons created from a battery and then 'injected' into the copper wire? If no, does that mean the battery loses power because the copper wire has run out of free electrons?

Where do the electrons come from when an electric generator is making electricity?  Is from the air?  Would a generator work in a vacuum?  Electrons have mass so where would they be pulled from if there is nothing?


It is well known that the following three definitions of a normal subgroup are equivalent:  $gNg^{-1}\supseteq N$ for all $g\in G$  $gNg^{-1}\subseteq N$ for all $g\in G$  $gNg^{-1} =N$ for all $g\in G$  However this equality comes from the fact both $g$ and $g^{-1}$ satisfy the requirements.  Can we have a subgroup $H$ such that $gHg^{-1}\subsetneq H$? clearly such a subgroup must be both of finite order and non-normal, which is one of the reasons I can't find a counterexample.  It can also be proven without much difficulty if such a $G,H, g$ existed then $g^{-1}$ would satisfy $g^{-1}Hg\supsetneq H$  Thank you kindly  Regards.

Let $G$ be a group, $H<G$ a subgroup and $g$ an element of $G$. Let $\lambda_g$ denote the inner automorphism which maps $x$ to $gxg^{-1}$. I wonder if $H$ can be mapped to a proper subgroup of itself, i.e.  $\lambda_g(H)\subset H$.  I tried to approach this problem topologically. Since every group is the fundamental group of a connected CW-complex of dimension 2, let $(X,x_0)$ be such a space for $G$. Since $X$ is (locally) path-connected and semi-locally simply-connected, there exists a (locally) path-connected covering space $(\widetilde X,\widetilde x_0)$, such that $p_*(\pi_1(\widetilde X,\widetilde x_0))=H$. The element $g$ corresponds to $[\gamma]\in\pi_1(X,x_0))$, and its lift at $\widetilde x_0$ is a path ending at $\widetilde x_1$. By hypothesis, $H\subseteq g^{-1}Hg$, which leads to the existence of a unique lift $f:\pi_1(\widetilde X,\widetilde x_0)\to\pi_1(\widetilde X,\widetilde x_1)$ such that $p=p\circ f$. This lift turns out to be a surjective covering map itself, and it is a homeomorphism iff $H=g^{-1}Hg$.  I was unsuccessful in showing the injectivity. If $x_1$ and $x_2$ have the same image under $f$, then $x_1$, $x_2$, and $f(x_1)=f(x_2)$ are all in the same fiber. I took $\lambda$ to be a path from $x_1$ to $x_2$. I have been playing around with $\lambda$, $p\lambda$, and $f\lambda$, but got nowhere.  Of course, there could also be a direct algebraic proof. On the other hand, if the statement is not true then someone maybe knows of a counterexample.


I want to find all instances where   wx.data.xxx  but not  wx.data.update OR wx.data.get  I tried (wx.data.)[^update][^get] but it doesn't work.

I know it's possible to match a word and then reverse the matches using other tools (e.g. grep -v). However, is it possible to match lines that do not contain a specific word, e.g. hede, using a regular expression?   Input:  hoho hihi haha hede   Code:  grep "<Regex for 'doesn't contain hede'>" input   Desired output:  hoho hihi haha


I'm sorry if this is a silly question. I've done quite a bit of searching and have not found any definition or name for this symbol/usage, despite immense popularity and convenience. The sources I've checked barely allude to the existence of such a thing, or give vague explanations. It has many varieties and from what I understand can be traced back to early usage of infinitesimals.  I'm talking about, the bar, bracket, or other vertical symbol used to denote a difference of a function between two points, as: $$\int_{a}^{b}{f(x)}=\biggl[ F(x) \biggr]_{a}^{b}=F(x) \Bigg|_{a}^{b}=F(x)\bigg]_{a}^{b}$$ I have seen other usages of such notation (e.g. in the context of partial derivatives, for example, where it can mean 'taken at this point') being defined, but not this usage. Some authors use it, some do not. I see it more often than not in elementary mathematics courses or introductory material, but it appears everywhere.  It does not seem to have an appropriate unicode character, in stark contrast to the dozens of types of spaces, dashes, periods, and other explicitly named vertical bars.  I haven't found anything but cursory mention of it on wikipedia, even in articles talking about the very symbols used to represent it, and despite it appearing on many images and formulas there. At some point I thought I misremembered its popularity, or may have confused it with something else.  Word cannot typeset it, and it doesn't have an exclusive macro in standard latex (as far as I know), although it is often used there as (depending on taste) a large bracket, bar, divider, etc.  What is the name of this notation? Does it have a definition? Is it used, in this specific meaning, anywhere else besides integration? Is there a 'correct' way to typeset it? (e.g. lar or medium square brackets, bar, single square bracket, etc)  I would be thankful if anyone has a source on it.

I've always wanted to know what the name of the vertical bar in these examples was:  $f(x)=(x^2+1)\vert_{x = 4}$ (I know this means evaluate $x$ at $4$) $\int_0^4 (x^2+1) \,dx = \left.\left(\frac{x^3}{3}+x+c\right) \right\vert_0^4$ (and I know this means that you would then evaluate at $x=0$ and $x=4$, then subtract $F(4)-F(0)$ if finding the net signed area)  I know it seems trivial, but it's something I can't really seem to find when I go googling and the question came up in my calc class last night and no one seemed to know. Also, for bonus internets; What is the name of the horizontal bar in $\frac{x^3}{3}$? Is that called an obelus?


I have the following enum  public enum Outcome {    DontKnow = 0,    Good = 1,    Bad = 2,    NotBad = 3 }   In my Results class, I have a property with this enum:  public class Result {    public int Id { get; set; }    public string Name { get; set; }    public Outcome FinalOutcome { get; set; } }   As I read data from the database -- using SqlDataReader -- how do I assign its value?  while(reader.Read()) {    Id = Convert.IsDbNull(reader[0]) ? Convert.ToInt32(0) : Convert.ToInt32(reader[0]);    Name = Convert.IsDbNull(reader[1]) ? string.Empty : reader[1].ToString();    FinalOutcome = Convert.IsDbNull(reader[2]) ? WhatGoesHere? : WhatGoesHere?; }

How can an int be cast to an enum in C#?


$$\frac{d^2x}{{\rm dt}^2}=-GM\frac{x}{{(x^2+y^2)}^\frac{3}{2}}$$ $$\frac{d^2y}{{\rm dt}^2}=-GM\frac{y}{{(x^2+y^2)}^\frac{3}{2}}$$ How can I solve those equations, I tried using wolfram alpha but it didn't work.

I have the following problem that I don't know how to solve:  Let $\textbf{r}(t)$ be a curve and let $r(t):= |\textbf{r}(t)|$. Let the curve $\textbf{r}(t)$ be defined by: $$\textbf{a}(t)=\frac{GM}{(r(t))^3}\textbf{r}(t)$$ Where $\textbf{a}(t) = \textbf{r}''(t)$ is the acceleration of the particle and $G,M \in \mathbb{R}$. Suppose that $\textbf{r}(t)$ and $\textbf{r}'(t)$ are not parallel. The objective is to determine the trajectory $\textbf{r}(t)$ in polar coordinates.  So basically we have the following equation: $$\textbf{r}''(t)=\frac{GM}{(r(t))^3}\textbf{r}(t)$$ The thing is that I don't know how I should proceed from now on. If we'd have just normal scalar function this would be a differential equation and I think I would be able to solve it, but like this I have no idea how to approach the problem. How can I solve this?  Edit: If $$\textbf{r}(t):=(x(t),y(t))$$ then the equation turns into the following system of equations: $$x''=\frac{GM}{(\sqrt{x^2 + y^2})^3}x$$ $$y''=\frac{GM}{(\sqrt{x^2 + y^2})^3}y$$ I don't know if this helps but I think that this turns thing easier perhaps.


I'm trying to solve :  For a stochastic process to be a Weiner Process it must have these properties:   $W(0) = 0$ so $W^2(0) = 0$ $E(W(t)) = 0$ but $E(W^2(t)) = t$ I think this is enough to prove that $W^2(t)$ is not a Weiner process   But I also want to prove the following:   $W^2(u) - W^2(t)$ is indepedent from $W^2(s) - W^2(r)$ given $u > t > s > r > 0$    In a Winer process the increments are normally distributed so to prove independence, I need to prove their covariance is $0$. But I don't know how to find if the increments for $W^2(t)$ are normally distributed or if there's another way to prove independence.

I'm trying to prove that the squared Brownian motion $(W_t^2)$ doesn't have independent increments, I tried using the covariance and it doesn't quite work, can anybody give me any pointer to how to prove this?


I am trying to figure out how I can prove that there exits $a\in R$ such that $a^3=2$ using the completeness axiom ?  I know that the completeness axiom for the real numbers states that for every non empty set $S$ which is bounded above, then the supremum of $S$ exists.So in the above example, would the supremum be equal to $2$ ?  How do I go about proving the above using the completeness axiom ? Could someone provide a proof for this problem ?

I am trying to prove the existence of the square root of $2$.  I have some steps with a very vague explanation and I would like to clarify.  The proof: Let  $$S=\{x\in\mathbb R\mid x\geqslant 0 \text{ and } x^2<2\}.$$  I understand the proof of LUB, ∝   and so I am at the step where $\alpha^2=2$.  I know that we are to prove by contradiction so we state let $\alpha^2 <2$ and $\alpha^2 >2$.  Now my instructor wants us to use the Archimedean Axiom $1/n = \varepsilon$.    $(\alpha^2 + 1/n)^2$  then what.....


Is it correct to say:  The city is difficult to turn into an economic center.  OR it must be:  It is difficult to turn the city into an economic center.  Thank you.

This question is relatively simple. I don't understand why we never use passive form of to infinitive after the adjective unless the subject is "it".  For example:     He is difficult to please.   People consider the example above a correct sentence. But:     He is difficult to be pleased.    People, for example, my teacher, said it sounds wrong and told me not to write this type of sentence. Is it grammatically flawed, or is it just a stylistic choice?


Suppose someone was born to a US-national parent in a foreign country and is thus a United States dual citizen. If that person (resident in their other country of citizenship) were to visit the USA for a few weeks, would it be legal for them to drive on their foreign drivers license since they wouldn't have an American one?

Question is pretty much in the title. I have a French drivers' license, and will be driving in the USA in a couple weeks. Is it accepted as-is, or must I get a translation? What preparation do I need to do?


I have the following data in a table:  ORDERID, PRODUCT,  QUANTITY 1,       potatoes, 10 1,       oranges,  20 2,       apples,   10 2,       oranges,  15 3,       pears,    20 3,       peaches,  12   I would like to query the table to filter out repeated products (e.g. oranges), taking only the latest (higher ORDERID) value. This should then result in:  ORDERID, PRODUCT,  QUANTITY 1,       potatoes, 10 2,       apples,   10 2,       oranges,  15 3,       pears,    20 3,       peaches,  12

Table:   UserId, Value, Date.   I want to get the UserId, Value for the max(Date) for each UserId. That is, the Value for each UserId that has the latest date. Is there a way to do this simply in SQL? (Preferably Oracle)  Update: Apologies for any ambiguity: I need to get ALL the UserIds. But for each UserId, only that row where that user has the latest date.


To be honest, I really don't understand this at all.  If we take cardboard for example, obviously gamma rays can penetrate cardboard because the light has such a high energy, and obviously radio waves can penetrate cardboard because a cell phone will work even when entirely enclosed in cardboard.  So high and low energy photons will pass through cardboard, but I cannot see through it, so it seems that all (or nearly all) visible light will be absorbed in the cardboard. I suppose that my hypothesis for this would be that the sun emits a large amount of light in the visible spectrum, so our eyes have evolved to detect it, and plants have evolved to absorb this same spectrum of light for photosynthesis (both plants and humans thus evolving to best utilize the EM radiation given off by the sun).  Since cardboard is made from plant material, it is thus specifically good at absorbing visible light, while allowing other wavelengths to pass through.  I have no idea if that is true, but even if it is, it only answers my question for plant-based material... I still have no idea why glass can hold in heat, yet visible light and radio waves may still pass through.

I think that something is invisible if it's isolated particles are smaller than the wavelength of visible light. Is this correct?  Why is air invisible? What about other gases and fumes which are visible?


the following is the code. but it doesn't work. what's wrong with it? thank you.        <head>    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />      <title>no title</title>    <script type="text/javascript">       function copyToClipBoard(content){  var clipBoardContent = '';  clipBoardContent = content;  window.clipboardData.setData("Text",clipBoardContent);  alert('have copied to the clipboard'); }            <body> <textarea rows="4" cols="60" id="url">www.example.com</textarea>      <input type="button" value="click me" onclick="copyToClibBoard (document.getElementById   ('url').value);" />  </body>

What is the best way to copy text to the clipboard (multi-browser)? I have tried: function copyToClipboard(text) {     if (window.clipboardData) { // Internet Explorer         window.clipboardData.setData("Text", text);     } else {         unsafeWindow.netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect");         const clipboardHelper = Components.classes["@mozilla.org/widget/clipboardhelper;1"].getService(Components.interfaces.nsIClipboardHelper);         clipboardHelper.copyString(text);     } }  But in Internet Explorer it gives a syntax error. In Firefox, it says unsafeWindow is not defined. A nice trick without using :


I have an elementary question. In this video(), Sal explains why swapping the limits of integration changes the sign of the result; In his video, he reasons that "dx"s in the reverse direction must have opposite sign too (because (a-b)/n must become (b-a)/n), however, that's something I don't remember I saw anywhere when I learned Riemann integral, to indicate that there's a relation between "dx"s and the order(higher/lower) of integral limits.  I have no problem with the result of definite integrals becoming negative since, well..., that's what happens when your ceiling is at the bottom of your basement! :D HOWEVER, I think it makes sense only when f changes to -f... but about the order of limits, I think it mustn't be so. Series are just algebraic sums, so I can still divide from b to a to divisions of (a-b)/n and then instead, sum all of them FROM RIGHT TO LEFT... So for example, d1.f + d2.f + d3.f + d4.f + d5.f becomes d5.f + d4.f + d3.f + d2.f + d1.f which has a similar sign and also because it's an algebraic sum, they must have the same values as well(To not confuse anyone, by "di" I mean division number i, and let's say "di" with less "i", refers to a "dx" at a position more towards the left). So I know integrals are very old and I'm definitely wrong :D But where am I making a mistake? Thanks.

So I'm refreshing on integration and venture across a property of definite integrals I've been taking for granted for quite some time:  \begin{equation}\int_{a}^{b} f(x) \mathrm{d}x =-\int_{b}^{a} f(x) \mathrm{d}x \end{equation}  Stewart's Calculus claims this property is owed to $\Delta x= \dfrac{b-a}{n}$, where $\Delta x$ becomes negative when you flip $a$ and $b$. If this is true, then it would be true for the (I know it's not the exact) definition of a definite integral:  $$\int_{a}^{b} f(x) \mathrm{d}x =\lim_{n \to \infty} \sum_{i=1}^{n}f(x_i^*)\Delta x$$  So I just did a quick verification of a simple definite integral of $x^2$ from $0$ to $1$. Using the Riemann sum definition I got $1/3$ and switching the limits of integration I got $-1/3$ as expected. However, I noticed that if you take $\Delta x$ to always be positive, in the sense that it's a width of a rectangle and couldn't possibly be negative, then the answer either way would be $1/3$. Which, in conclusion, brings me back to my question: wouldn't it be simpler to take $\Delta x$ as a distance or width (always positive) and eliminate this property of integrals? Leaving us with:  $$\int_{a}^{b} f(x) \mathrm{d}x =\int_{b}^{a} f(x) \mathrm{d}x$$  To me this makes more sense, because the area under a curve should be maintained when calculated from any direction.


I've read tutorials on getting 1 mesh to conform to the shape of another via a combination of mesh deforming to a flat plane (with a solidify mod setup but not applied), parenting the object to the flat plane, and then applying a shrinkwrap on the flat plane (above solidify in the stack).    As you can see below, this works, but also deforms my original mesh badly.  Setup:    and the result:    Altering the shrinkwrap mode doesn't resolve this, any help is appreciated!!

I have a basic sphere and with freehand addon i have created and arc and bevel that with the circle. To the arc its been bevel like a tube shape.   Tube shape   Adding shrinkwrap modifier the tube shape became flat  Tube flat   Whats wrong why the tube gone flat after adding shrinkwrap modifier. Any suggestion or help thanks.


I would like to extract a portion of an equirectangular 360x180 panorama taken with a Theta S and convert it to what I think is a rectilinear image (a picture where straight lines are shown as such regardless of the lines' direction). Could you please advise on how to do it? Thanks in advance!

I'm not sure how to ask my question in generic terms, but here's what I want to do.  I have a 360°x180° panorama photo. I took the photo with an app (Google PhotoSphere).  Unfortunately my app doesn't save the individual photos I took, only the auto stitched panorama, with the "center" of the photo of its choosing.  I'd like to recenter, crop, reproject, etc. the photo, just as I would as if I had stitched individual photos into a panorama with a panostitching application like Hugin.  How can I bring a full panorama photo into Hugin (or similar software) so that I can manipulate the photo to my choosing?   My goal would be to export a new panorama photo (and not necessarily a 360x180).  Currently my only option is to view the photo in panorama viewing software, and take screenshots. However, this of course limits my resolution to my monitor, and only in the projection they're presenting it in.


I am looking for complex test cases that will challenge my WebDriver Java skills.  Does anyone have such an example? Links? Own test cases that has put your automation skills to the test?

Where can I find sample or real Selenium projects. All the material I can find on github and on internet are basic, and never intermediate or advanced.  How does a real Selenium project look in real life? How can I find sample code?


can I use----As per mine and John's understanding we concluded that...

I just stumbled upon a :     My wife and I's seafood collaboration dinner. How does it look?   Sure enough, the top comment immediately points out that it should be "my wife's and my". However, a cross-post to the Grammar subreddit produced :     It's fine as it is written. "my wife and I" is a noun phrase, functioning as a subjective pronoun in the singular and made possessive with the apostrophe. It is exactly the same as "our".      It seems weird because you would never use "I's" on its own but it is not on its own here - it is part of a noun phrase.   That's a rather intriguing argument. Does it hold any water?


My laptop has 4 gigs of DDR2 RAM and I am currently using a 32bit windows 7 OS. Will I notice any performance difference if I upgrade to 64bit or does all the benefits of X64 start at 5GB of RAM?

I've recently purchased Windows 7 Ultimate.  I have an AMD Athlon64 X2 5000+ with 2GB DDR2 RAM.  I know RAM has gotten much cheaper, I know, I know, but I am not going to be able to upgrade my RAM for about a year.  My question is obviously this; will I get any benefit from installing 64-bit Windows over 32-bit if I'm only using 2GB of RAM?    As I understand, the minimum requirement is 2GB & max is 192GB so if the minimum for 64-bit is 2GB & the minimum for 32-bit is 1GB will I lose performance if I chose to install 64-bit at it's minimum requirement over 32-bit whose minimum is half the amount?  I would like to install the 64-bit edition if only because it's the future.  192GB of RAM! that's incredible! Plus I've heard it simply performs better.  But that is with a larger amount of RAM.  I've tried to make this question as easy to decipher as possible.  Any advice would be greatly appreciated.


'''' What are the numbers after '='? Is it a file name like .php or .html file or its a media file like .mp4?

I am new to PHP. In the path of learning PHP language, I notice that, some website would this kind of URL:  www.website.com/profile.php?user=roa3&...  My questions:   What is the "?" symbol used for?  If I were develop a php website, must I use it in my URL? For example, after a user(roa3) successful logged in, I will redirect to "www.website.com/profile.php?user=roa3" instead of "www.website.com/profile.php" What are the advantages and disadvantages of using it?


How do you center a div or anything else horizontally, so that on both sides the empty spaces are equal? And the div is exactly in the middle? No matter the size of the objects.  Take for example: the Stackoverflow site itself.  Except for the black header on the top of this site, everything is in the middle and the empty spaces on both sides are equal to each other.  I've searched for a long time, but I only encountered the wrong answers or vague answers.  Please help and thank you!

How can I horizontally center a
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Foo foo


Now that Tyrion is no longer a fugitive of the Crown and as the most senior successor to be ruler of Casterly Rock, can he be head of House Lannister as well as being Hand of the King?

I am re-watching Game of Thrones and I came across this question.  Tywin Lannister is the Lord of Casterly Rock - But since his death, who is now the Lord of Casterly Rock?    Tyrion can't be the Lord as he is a fugitive. Jaime Lannister cannot be the Lord either as he's in the order of the Kingsguards. There is no indication that it's Cersei.   Has this ever been mentioned? I imagine that since Tywin's death, there would be a lot of enemies who will see this as a weakness and try to take this land?


I looked for this before but I couldn't find it exactly, so let me know if it's a duplicate. My question is, should categorical variables be one hot encoded to run Random forests? Or just transforming them to nominal is fine? Take into account that there are some continuous variables in my model as well, if that makes any difference. Also, I'm using Python's sklearn. I did search this but anywhere I looked there was a different answer. I read  article as well which is quite informative, but I wanted to know if there's any consensus of some kind, or if any trustworthy reference can be found? Edit: Decided to quickly try the one hot encoding implementation and the first thing I notice is that it is taking considerably longer to run.

I understand that when label encoding is used ,the numeric number can be interpreted to have an order and a model could assume a linear relationship. However shouldn't this be a problem when there are in-fact many levels in a categorical variable e.g. country.  How about the case of binary variables which for e.g. instead of gender.male ( 1,0) what if I just used Gender ( 1,0) where gender = 0 is female and 1 is male for instance. This shouldn't impact the model as much as a label encoding to a feature with multiple levels? How would this be for a case where I have a feature three levels ( -1,0,1) where -1 means not applicable, 0 means 'No' and 1 means 'Yes', so instead of having 2 columns feature.not_applicable(1,0) and feature.No(1,0) - mathematically how would models be impacted - models here would be GLMS,  boosting models, Random forests etc. Is label encoding recommended when feature has say <=3 to 4 levels and above that is recommended to do one hot encoding or $n-1$ dummy variables?


I was reading "Serial Rings" by Gennadi Puninski. There it is written that , "Since every module is a homomorphic image of a free module, every projective module is a direct summand of free module".(ie. if $P$ is a  projective module, there exists a free module F such that, $ F=P \oplus T$ for some module $T$.) But I can't understand how "Every module is a homomorphic image of a free module" implies that "Every projective module is a direct summand of free module". (I have found a proof for "Every projective module is a direct summand of free module" but the first part of the above mentioned sentence wasn't used there.)

$P$ is projective . Show that $P$ is a direct summand of a  free $R-$ module  I am using the definition of a projective module as $P$ is projective if every exact sequence $M\rightarrow P\rightarrow 0$ splits   How to proceed?


I have made some research how to install Jupiter on Ubuntu 14.04:  In therory:   download the program (noarch.rpm) from  convert .rpm into .deb, by using alien program; add missing jupiter group to Ubuntu; install recently converted deb package;   In practic:  sudo apt-get install alien sudo groupadd jupiter cd ~/Downloads sudo alien -k jupiter-0.1.11-1.noarch.rpm --scripts sudo dpkg -i jupiter_0.1.11-1_all.deb   ...in general, it works (it appears in ps aux | grep jupiter list), but there is still missing jupiter indicator. Someone knows how to get this done to work properly?

I'm trying to install the Jupiter power settings app but, I read it is no longer compatible with the new kernel. Is there a similar program or a way to manage the power settings on 13.04?


This is an exercise from Conway that I am stuck at. I think the function $φ$ is clearly continuous for points $(z, w)$ such that $z$ and $w$ are not equal. However I can't show that $φ$ converges to the derivative of $f$ at z as $(z, w)$ goes to points where $z$ and $w$ are equal...  Also it is clear that for each fixed $w$, $f$ is analytic for points $z$ not equal to $w$. But how can I show that $f$ is analytic at $z=w$? Could anyone please help me with this problem?

For the first proof of Cauchy's integral formula, Conway in his book "Functions of One Complex Variable" (Chapter IV, section 5.4) uses the following claim:     Let $G$ be an open subset of $\mathbb C$ and $f : G \to \mathbb C$ an analytic function. Then define $\varphi : G \times G \to \mathbb C$ as   $$ \varphi(z,w) = \begin{cases} \dfrac{f(z)-f(w)}{z-w}, && z\neq w \\   f'(z) && z=w \end{cases}. $$   Then $\varphi$ is continuous on $G \times G$.   Unfortunately, he does not give a proof, leaving it as an exercise (Exercise 1).  I tried to make a direct proof by taking $|z-z_0| + |w-w_0| < \delta$ as a neighbourhood of $(z_0,w_0)$, but it lead to nowhere. I understand, that $z \mapsto \varphi(z,w)$ and $w \mapsto \varphi(z,w)$ are both holomorphic and continuous, but I do not see how one could use it.  I also saw this claim in several lecture notes but it goes unproven there either.  I would appreciate a hint, we have this problem as a homework.


The objects look fine in rendered view, but once I render out the frames these seams appear. Super subtle but want to get rid of them. Any ideas?

I'm a beginner in blender. Trying to texture a 3d furniture model which was downloaded from the manufacturer site. Geometry is made of stretched triangles. This causes problems of stretched texture which is visible on render.  I unwrapped the model with "smart uv project" but the geometry is still stretched Is there any solution to texture it properly or I need to remodel it to make it quads?  What if I need to use dozens of real furniture models like this?  Should I model everything from scratch in blender?  some pictures to explain:enter image description here


I have a matrix whose columns are highly correlated, hence using this matrix in compressed sensing algorithms is not giving satisfactory results. So is there any way in which we can reduce the linear dependency between the columns of the matrix?  Snapshots of measurement vector 'y', sensing matrix'A' and required solution vector'x' are attached

In today's pattern recognition class my professor talked about PCA, eigenvectors and eigenvalues.   I understood the mathematics of it. If I'm asked to find eigenvalues etc. I'll do it correctly like a machine. But I didn't understand it. I didn't get the purpose of it. I didn't get the feel of it.        I strongly believe in the following quote:     You do not really understand something unless you can explain it to your grandmother. -- Albert Einstein   Well, I can't explain these concepts to a layman or grandma.   Why PCA, eigenvectors & eigenvalues? What was the need for these concepts? How would you explain these to a layman?


"times" is the preposition equivalent to "multiplied by". what is the preposition equivalent to "divided by"?

Given the following expression:     5 (+-×÷%) 4   You would say "5 plus 4," "5 minus 4," "5 times 4," "5 divided by 4," and "5 mod(ulo) 4" respectively.  As far as I know, "divided by" does not have any shorthand form in the same way the above examples do.


The company I'm working for has a HUGE class (Globals.m) that is a singleton. It stores mostly a bunch of BOOLs that should go into NSUserDefaults, but there are also pointers to things like videoplayers that belong to various viewcontrollers. I am fairly new to iOS development (and I'm a lowly intern), but I know in my gut that the code smells to high heaven. How can I explain why using a singleton to store all the variables is bad?  Edit: I don't mean singletons are bad, I just mean in this case. Essentially every significant variable in the app is stored in this one instance.

The  is a fully paid up member of the 's , but it lately seems rather orphaned by the developer world. I still use quite a lot of singletons, especially for , and while you have to be a bit careful about multithreading issues (like any class actually), I fail to see why they are so awful.  Stack Overflow especially seems to assume that everyone agrees that Singletons are evil. Why?  Please support your answers with "facts, references, or specific expertise"


I was told to switch to nginx or at least to mpm_worker. But really, how can I estimate if my server is not really overloaded even with mpm_prefork?  My system is:   GCP 1 CPU + 3,75GB Debian 8 Apache 2.4 with mpm_prefork Varnish cache, Memcache   Some php.ini settings  max_execution_time = 30 max_input_time = 60 memory_limit = 1536M   Some other various standard apache modules, without fastcgi and without php-fpm.  <IfModule mpm_prefork_module>     StartServers             5     MinSpareServers       5     MaxSpareServers      10     MaxRequestWorkers     250     MaxConnectionsPerChild   0 </IfModule>  KeepAlive Off   And I have about 20 small wordpress blogs on it.  So how many concurrent users can I take all together on all sites? I don't need exact numbers. I want to understand if it's 10s 100s or 1000s? Probably not 10000s. But if it's something like 250 same time online - I think It's still good for now.  Also, should I set the memory limit to 3GB? OR let the left 2GB to be used by varnish is a good idea?  Completed 1000 requests Finished 1000 requests Server Software:        Apache/2.4.10 Server Hostname:        sochi.asp.sale Server Port:            443 SSL/TLS Protocol:       TLSv1.2,ECDHE-RSA-AES256-GCM-SHA384,2048,256 Document Path:          / Document Length:        199165 bytes Concurrency Level:      100 Time taken for tests:   12.041 seconds Complete requests:      1000 Failed requests:        0 Total transferred:      199546499 bytes HTML transferred:       199165000 bytes Requests per second:    83.05 [#/sec] (mean) Time per request:       1204.067 [ms] (mean) Time per request:       12.041 [ms] (mean, across all concurrent requests) Transfer rate:          16184.28 [Kbytes/sec] received Connection Times (ms)               min  mean[+/-sd] median   max Connect:       12  711 1471.9    307    6868 Processing:    23  492 960.2    253    7588 Waiting:        2  302 957.0     76    7043 Total:         35 1203 2005.6    524    7629 Percentage of the requests served within a certain time (ms)   50%    524   66%    534   75%    608   80%    644   90%   7164   95%   7186   98%   7188   99%   7189  100%   7629 (longest request)

This is a  about  Related:      I have a question regarding capacity planning. Can the Server Fault community please help with the following:   What kind of server do I need to handle some number of users? How many users can a server with some specifications handle? Will some server configuration be fast enough for my use case? I'm building a social networking site: what kind of hardware do I need? How much bandwidth do I need for some project? How much bandwidth will some number of users use in some application?


I am currently working on this problem that asked me to calculate the ACF of  $Y_{t}=x_{t}x_{t-1}, x \sim IID{\left\lbrace0, \sigma^{2}\right\rbrace}$  what I've done so far is, I have proved that $E[y_{t}]=0$, so I'll take it as given in the following calculation.  here I am calculating the ACF of $y_{t}$: $$ \begin{aligned} COV(y_{t+h}, y_{t}) &= E[(y_{t+h} - E[y_{t+h}])(y_{t} - E[y_{t})]\\ &= E[y_{t+h}y_{t}]\\ &= E[x_{t+h}x_{t+h-1}x_{t}x_{t-1}]\\ \end{aligned} $$  given $x \sim IID{\left\lbrace0, \sigma^{2}\right\rbrace}$, therefore we can separate the expectation above into: $$ E[x_{t+h}x_{t+h-1}x_{t}x_{t-1}] = E[x_{t+h}]E[x_{t+h-1}]E[x_{t}]E[x_{t-1}] \qquad(1) $$  if $h \neq 0$, then $(1)=0$ because we have $E[x_{t}]=0$  if $h = 0$, then (1) is  $$ E[x_{t}]E[x_{t-1}]E[x_{t}]E[x_{t-1}] = 0 $$   which we could then conclude that ACF of $y_{t}$ is 0.  it all looks correct me but the solution gives different answer when $h =0$, could anyone spot what I've done wrong?  thanks!   EDIT:  given the comments, there's one thing I've done wrong above; when $h = 0$,  the independence cannot be applied because two or more indices are the same. this implies dependence (I think)  I therefore did,   $$ \begin{aligned} E[x_{t+h}x_{t+h-1}x_{t}x_{t-1}] &= E[x_{t}x_{t-1}x_{t}x_{t-1}]\\ &= E[x_{t}^{2}x_{t-1}^{2}] \qquad (2) \end{aligned} $$   I am stuck again because I don't know how to prove  $$ (2) = E[x_{t}^{2}]E[x_{t-1}^{2}]\qquad (3) $$   one more hint, I could solve it!

Is the claim that functions of independent random variables are themselves independent, true?   I have seen that result often used implicitly in some proofs, for example in the proof of independence between the sample mean and the sample variance of a normal distribution, but I have not been able to find justification for it. It seems that some authors take it as given but I am not certain that this is always the case.


why the Vitali set has size $2^{\aleph_0}$ and therefore there is a bijection between $\mathbb R$ and the Vitali set? thanks

I am a bit confused about the cardinality of the Vitali sets.  Just a quick background on what I gather about their construction so far:  We divide the real interval $[0,1]$ into an uncountable number of disjoint classes in such a way that two numbers $x$ and $y$ are in the same class if their difference x-y is a rational number. Therefore the equivalence relation on the real numbers would be: $x\sim y\iff x-y\in\mathbb Q$.   The cardinality of our classes is equivalent to the cardinality of $\mathbb Q$, so the classes have countably infinite elements.  How many of these classes are there? As each only has countably infinite elements, but each element of $[0,1]$ lies in one class, there are uncountably infinite classes.  Now, using the axiom of choice, we take one element out of each class and put it in the set V. This is a Vitali set.  Hopefully this is all good at this point.  So each Vitali set should have uncountably many elements (because we have uncountably many classes), but there should be countably many Vitali sets (because each class has countably many elements) correct?  But then why does  state that "There are uncountably many Vitali sets..."?


How can I break the table cell data automatically to adjust the page width when data in both columns are exceeding? Below is an example of the problem.     \begin{center}     \begin{tabular}{|l|l|}     \hline     \textbf{Scrum}  & \textbf{Large Scale Scrum (LeSS)}\\     \hline     Comprises of one team and one product & \begin{tabular}{@{}ll@{}} Comprises of up to 8 teams\\      All Teams are in a common Sprint to deliver a common product\\     \end{tabular} \\     \hline     \end{tabular}     \captionof{table}{Comparison between Scrum and Large Scale Scrum }\label{LeSStable}     \end{center}  P.S: I am on a very beginners level

I'm making a tabular and I'd like to automatically do a like break rather than going beyond the page.   This is my tabular code:  \begin{table}[h] \begin{tabular}{|l|l|l|} Use Case Navn:          & \multicolumn{2}{l}{Opret Server} \\ Scenarie:               & \multicolumn{2}{l}{At oprette en server med bestemte regler som tillader folk at spille sammen. More Text more text More Text} \\ \end{tabular} \end{table}   This is my preamble:  \documentclass[danish,a4paper,twoside,11pt]{report} \usepackage{babel} \usepackage[utf8x]{inputenc} \usepackage{natbib} \usepackage{graphicx} \usepackage{epstopdf} \usepackage{titling} \usepackage{color} \usepackage{xcolor} \usepackage{nag} \usepackage{tabularx}  \newcommand{\myparagraph}[1]{\paragraph{#1}\mbox{}\\}   This is how it looks right now:


What axioms of set theory are needed for Cantor's diagonalization argument to work and why?  What happens if we do away with some of these axioms (for instance Axiom of Choice)?

Math people:  It is my understanding that set theorists/logicians compare cardinalities of sets using injections rather than surjections.  Wikipedia defines countable sets in terms of injections.  Cantor's diagonal proof that the real numbers are uncountable involves showing that there is no surjection from $\mathbb{N}$ to $(0,1)$.  So do I need the Axiom of Choice to accept Cantor's Diagonal Proof?  I browsed the Similar Questions and I could not find an answer.  I apologize if this is a duplicate.  StEFAN (Stack Exchange FAN)


I was reading  to understand the inner workings of bash when I saw this:  You should never have . in your PATH as it poses a security risk, among other problems.  and couldn't figure out why this is a security risk and the answer didn't elaborate.

On UNIX-like systems over the years (most relevantly to me, Linux), I've noticed that . (current dir) is never in the $PATH by default.  Why is this?  I recall reading years ago that it was a security problem, but the article I read didn't explain what exactly the problem was.  Is it because someone could leave a malicious version of ls or cp in a directory, and I'd end up running it without realizing it was there?


I am just a little unclear about what I am supposed to do here.  Let $\phi: G $ to $J$ be a homomorphism onto all of $J$. Let $H$ be a normal subgroup of $G$ and let $K=\phi(H)$ be the image of $H$ under the homomorphism.  I have showed that K is normal to J. I now need to provide an example that K could not be normal to G if $\phi$ is not onto.  Do I need to find a G,J,K, and H such that it there is a homomorphism but it is not onto? Is this the right path? Because if it is then I have thought and thought and I am stuck.

I want to find an example of a homomorphism $f:G\to H$ such that $A$ is a normal subgroup of $G,$ but $f(A)$ is not so in $H.$  I know that if $f$ was onto $f(A )$ must be normal , but otherwise i want to find an example!


Many other languages posses the ability to suppress diagnostic messages on specific sections of their source code, while still reporting these messages in other sections.  For example, in C++ with gcc one can use #pragma GCC diagnostic commands to turn compiler messages on and off, and Java has the @SuppressWarnings annotation.  Does LaTeX posses a similar feature or another way to disable diagnostic messages in a specific section of code?    As a specific example, I have some code that triggers these warnings:  paper.tex:8: LaTeX Font Warning: Font shape `U/fontawesometwo/m/it' undefined(Font)     using `U/fontawesometwo/m/n' instead on input line 8. paper.tex:20: LaTeX Font Warning: Font shape `U/fontawesometwo/b/n' undefined(Font)     using `U/fontawesometwo/m/n' instead on input line 20.   How can I turn off this warning, but only for those two specific lines of that specific file?  Note that I am not looking for the 'correct' way to fix warnings, I am only looking for a general method to suppress warnings.

I have to use a format that uses catoptions package; when I use it in conjunction with tikzcircuit I have a (mostly harmless, I think, but annoying in IDEs) warning ---  \documentclass[border=10pt, 12pt]{standalone}% adequate for simple figures \usepackage{catoptions}  %% the above packages is loaded in the class format --- suppose I can edit only  %% below here (or use some class option, obviously). Baically, I have  %% \documentclass{mycompanyclass}  %% ...and the package catoptions is loaded before I can load any other package  \usepackage[siunitx]{circuitikz}% Loading circuitikz with siunitx option \usetikzlibrary{arrows} \begin{document} \null \end{document}   which outputs (excerpt):   ... (/usr/share/texmf/tex/generic/pgf/libraries/pgflibraryarrows.code.tex)  Package catoptions Warning: Option 'europeanvoltages' multiply defined (catoptions)                in family 'circuitikz.sty' (catoptions)                (in package 'circuitikz').   Package catoptions Warning: Option 'europeanvoltage' multiply defined (catoptions)                in family 'circuitikz.sty' (catoptions)                (in package 'circuitikz').   Package catoptions Warning: Option 'europeanport' multiply defined (catoptions)                in family 'circuitikz.sty' (catoptions)                (in package 'circuitikz').  (/usr/share/texlive/texmf-dist/tex/latex/circuitikz/circuitikz.code.tex ...   Is it possible to get rid of the warning?


So I have my PC hooked up to my receiver via HDMI to display my screen on my TV. But anytime the receiver is turned on all my screens go plank for a period of time is there a way to prevent this?  I have an Nvidia GTX 980Ti and Two Monitors the TV is set to mirror the main screen.   The HDMI cable for the TV is run to a Denon avr-x3200w receiver. Then from the receiver to the TV.  My PC fully recognizes the Denon avr-x3200w in the Nvidia settings.  It just when the receiver is turned on everything goes black and same for when its turning off. Its like its causing the graphics to reset.

Configuration  I have my desktop connected to two monitors, of which one is the primary monitor (best quality). I have a server as well, and its video output is connected to the alternate input of my primary monitor. That way, I can switch my monitor to display the output of my server, so I can quickly perform some actions on it.   Problem  However, when I switch my primary monitor to its alternate input, windows 10 on my desktop PC detects that my primary monitor 'disconnected'. Windows 10 then proceeds to make my secondary monitor my primary monitor, and moves every single window to that screen. When I`m done with my server (usually just a couple of seconds to make some quick changes) I press the button on my primary monitor to use its main input again. Windows then detects that it is connected again and makes it my primary monitor again, but leaves all windows on my secondary monitor!  This behaviour is maddening, I have to drag every single window back to where it was before to just be able to continue my work. This takes a lot longer than the actions I performed on my server.  Question  How do I prevent windows 10 from detecting monitor changes?   Or alternatively how do I get it to put back the windows to their original place when it changes primary monitor a second time?  Similar posts  I have found a similar  for display port, but I use HDMI. I have also found a similar  for windows 7, but I use windows 10 which does not have the TMM variable in the registry. I have not been able to find a post with exactly my problem, or found a setting for this in windows 10.


There should be one login for every site on Stack Exchange. I have to login each time I go to a different site, for instance from  to  (ELL).  For example, on Google's websites if a user logs in on one site, say Gmail, then if he goes to Google+ or YouTube, he does not need to enter his credentials again to log in.  But here we have to give credentials each time on a different site.  I request a similar feature, for the ease of users.  I get the cookie thing that if you have already logged in then you don't need to log in again when you come back to the site.  But what I want is that on each site where the user is registered, say Stack Overflow, Meta Stack Overflow and English Language & Usage, he should be able to use them all in flow once he is logged in anyone of them.

Why do I have to log in to each site individually?  If I were to clear my cookies, the first time I visit each SE site, I need to login to each site.  This can be a little annoying.  Example:  First, I go to SO, I have to log in there.  Not a big deal.  I want to check what's going in Meta.  I go to perform some action and I realize I'm not logged in.  I think, well this is kind of annoying, but it is only a few clicks.  Now I go to my network profile and click accounts because I want to review my accounts on other SE sites.  SE obviously knows all of these accounts are linked because it shows them to me.  So I open each one I want to view in a new tab.  I go to each of these tabs, expecting to be able to use the site, but I need to log in again, for each one.  Why?  They are linked, the system know this, and I am already logged in.


I have few questions on the meta analysis.  First, the data is longitudinal and according to the CMA (comprehensive meta analysis) guidebook "Working with more than two outcomes per study The formulas presented for a difference based on two outcomes can be extended to accommodate any number of outcomes using contrasts." My concern is how to choose proper contrast. The data shape is in a way that intervention shows better results for earlier time but both intervention and control have bouncing back effect and eventually get to similar results over time. So my first trial for the contrast was using same weight. For example, contrast 1 = T0-0.5T1-0.5T2 conrast 2 = T0-1/3T1-1/3T2-1/3T3 and so on. (Different studies have different time points). In this way I noticed that the equal weight contrast results in not significant differences. Would it be valid if I put more weight into earlier time points (T1,T2) and less weights to later time points (T3 and on)?

I have question on the methods of performing meta analysis. I have data that consists of multiple Randomized Control Trials (RCT) with different dose levels and observational studies with different dose level as well.  The responses are brain pressure measured as continuous random variable.  So my understanding is that I have to perform meta analysis on the studies that share same level of treatment (same dose) and I can include both RCT and observational studies in that treatment level analysis.  Is there any thing I can do as a whole study? What kind of answer should I provide to my client?


Let $x \sim y$ be defined as meaning that the ordered tuple $(x, y)$ is in some set $S$. If this is the case, an equivalence relation on the set $S$ is defined as a subset of $S \times S$ with the following properties:   For all $x$ in $S$, $x \sim x$. If $x \sim y$, then $y \sim x$. If $x \sim y$ and $y \sim z$, then $x \sim z$.   I think this is an over-determined definition, because (1) is a consequence of (2) and (3), as long as it contains anything in addition to the empty set:  Assume that the equivalence relation contains at least point, $x \sim y$. By (2), it contains $y \sim x$. By (3), since $x \sim y$ and $y \sim x$, we also have $x \sim x$. Since we put no constraints on $x$ except that it be a part of the relation, this implies that for any point $x \sim y$, we have $x \sim x$. (We also have $y \sim y$, since $x \sim y$ implies $y \sim x$.) So why do we need to specify (1)?

An equivalence relation is defined by three properties: reflexivity, symmetry and transitivity.  Doesn't symmetry and transitivity implies reflexivity? Consider the following argument.  For any $a$ and $b$, $a R b$ implies $b R a$ by symmetry. Using transitivity, we have $a R a$.  Source: Exercise 8.46, P195 of Mathematical Proofs, 2nd (not 3rd) ed. by Chartrand et al


Why there is no output? Why doesn’t an ambiguity error occur?   #include <iostream> using namespace std; class A{ public:     A(){         cout << "Class A";     }     A(int a = 0){         cout << "A";     } };  int main() {     A a();     return 0; }   So when we create an object “a” of type “A”  A a();, compiler calls a constructor without parameters, doesn’t he?     In C++, We can have more than one constructor in a class with same name, as long as each has a different list of arguments. A constructor is called depending upon the number and type of arguments passed.   While creating the object, arguments must be passed to let compiler know, which constructor needs to be called.

Is there any good reason that an empty set of round brackets (parentheses) isn't valid for calling the default constructor in C++?  MyObject  object;  // ok - default ctor MyObject  object(blah); // ok  MyObject  object();  // error   I seem to type "()" automatically everytime. Is there a good reason this isn't allowed?


Im trying to get an ai chat into a gui sp i can chat with it there instead of just in the console. But when i have the 2 packages and try to run them i get error in my code, but i dont see any problems in the code itself   since i theres no clear error in my code, im not sure what code to post here. so heres a image of line 34-35

I am getting a NoClassDefFoundError when I run my Java application.  What is typically the cause of this?


I am trying to remove a meteor in my game for when it his a bullet but there seems to be an error, and I do not now another method to remove the object.  for (int i = 0; i < numA; i++) {     if (meteor[i].isVisible())       meteor[i].move();     else meteor[i].remove(i);     }

Given an array of n Objects, let's say it is an array of strings, and it has the following values:  foo[0] = "a"; foo[1] = "cc"; foo[2] = "a"; foo[3] = "dd";   What do I have to do to delete/remove all the strings/objects equal to "a" in the array?


When I execute   echo `man ls` > tem.txt   I get unformatted output in the text file, I mean output without any new lines, just continues sentences. How do I get formatted output ? For example, unformatted output looks like:  LS(1) User Commands LS(1) NAME ls - list directory contents SYNOPSIS ls [OPTION]... [FILE]... DESCRIPTION List information about the FILEs (the current directory by default). Sort entries alphabetically if none of - cftuvSUX nor --sort is speci‐ fied. Mandatory arguments to long options are mandatory for short options too. -a.................

Or, an introductory guide to robust filename handling and other string passing in shell scripts.  I wrote a shell script which works well most of the time. But it chokes on some inputs (e.g. on some file names).  I encountered a problem such as the following:   I have a file name containing a space hello world, and it was treated as two separate files hello and world. I have an input line with two consecutive spaces and they shrank to one in the input. Leading and trailing whitespace disappears from input lines. Sometimes, when the input contains one of the characters \[*?, they are replaced by some text which is is actually the name of files. There is an apostrophe ' (or a double quote ") in the input and things got weird after that point. There is a backslash in the input (or: I am using Cygwin and some of my file names have Windows-style \ separators).   What is going on and how do I fix it?


I've seen some discussions about the command of "fire" before gunpowder was invented. That may be "shoot", "loose", "throw" etc. But what was the command of "fire at will"?  Are there any clues?  Update:   "Fire at will" is a tactic which has long existed in history. After the invention of gunpowder, we call it "fire at will". Before gunpowder, what did we call this tactic? Was there a common used phrase or not?

Did the verb “fire a weapon” exist before the actual introduction of firearms on battlefields?  More specifically, does it make sense for a creative work to have archers (or whatever ranged weaponry) be told to “fire!”, when the world they live in has not yet seen firearms?  It seems some kind of an anachronism to me, since before firearms, “fire” would never propel any projectile...  I've seen several movies do it; I can't remember them all, but for instance I verified it in The Lord of the Rings trilogy (left), Kingdom of Heaven (top right), and more recently Frozen (bottom right):    The first two do it several times (with Kingdom of Heaven also using it on ballistae, and The Return of the King even having Aragorn ask Legolas to ), whereas firearms never appear on the battlefields they feature (Kingdom of Heaven is set in the 12th century; as for The Lord of the Rings, apart from one occurrence of a witchcraft-ish bomb, it's archery and medieval siege engines all the way).  Frozen may be debatable, happening probably somewhere in the 18th or 19th century, but since we only see swords, spears and the like, it made me flinch to hear crossbowmen use “fire!”.  I've also noticed other movies avoiding this, using “loose!” instead, such as Troy (left) and Gladiator (right):    This makes me think it would be the right thing to say instead... although I'm still wondering why not use “shoot”, which seems simpler to me.


I am having a custom field in which I'm storing text and emojis but when I am querying the record its giving unicode character for ex: &#127885; instead of 🎍.  I have already used EncodingUtil.URLENCODE(str,'UTF-8') and EncodingUtil.URLDECODE(str,'UTF-8') but of no use. Please help me with this

I've set up the following test page: Visualforce Page: <apex:page controller="Emojis" action="{!Emojis}" >  <apex:form >     <apex:actionPoller interval="5" reRender="emoji"/>      <apex:outputText id="emoji" value="{!emojiCase.Subject}"/>  </apex:form>  </apex:page>  Apex Controller: public class Emojis {      public Case emojiCase {get;set;}      public void Emojis() {         // This is a case which has Emojis in the Subject         emojiCase = [SELECT Id, Subject FROM CASE WHERE CaseNumber = '00034143'];     }  }  When the page first loads, the page action fires and retrieves the case with emojis, and it looks like this:  However when the actionPoller rerenders the output text, it changes to this:  I can't figure out why it does this, does the encoding change upon refresh?


I want to drive this Piezo Transducer () directly from a pin on my STM32F0 microcontroller. I don't want to use a BJT transistor because the max current consumption of the transducer is so low (5mA). Right now I have the following schematic.          – Schematic created using   The pin on the STM32F0 can source a max of 3.3V (peak-to-peak). Since the max current consumption of the transducer is 5mA, I want to limit the current going into it to 2.5mA to be on the safe side. Using Ohm's Law, I get a resistance value of R = \$\frac{V}{I}\$ = \$\frac{3.3V}{0.0025A}\$ = 1320\$\Omega\$  Is this circuit correct or am I missing something fundamentally?

I want to drive this piezo transducer () at 3V and 4kHz with STM32F0 microcontroller. This is a follow-up to my previous question (). Since then, I've made some progress and come up with this circuit:         – Schematic created using   R1 is to limit the amount of current the microcontroller pin draws and R2 is to discharge the speaker when there is no output to the speaker (since it acts like a capacitor). The MCU can draw a max of 25mA of current, but the speaker only uses a max of 5mA when driven at 3V and 4kHz. So I will limit the current draw from the MCU to 10mA. This gives i_c a value of 10mA and R1 a value of \$330\Omega\$.  (R1 = \$\frac{3.3V}{10mA}\$). Since the speaker draws a max of 5mA, i_s = 5mA and i_b = 5mA. The schematic with the values plugged in is:          To determine R2, I know I want 3V to be applied to the speaker, so the voltage drop over R2 will be 3V. Using Ohm's Law, \$R2 = \frac{3V}{5mA} = 600\Omega\$.  My two main questions are:   Is this circuit fundamentally correct to drive the transducer? Do the values for resistors R1 and R2 make sense or am I overlooking something?


I am applying for a standard visitors UK visa this week. I have a good monthly income and stable employment. I had my brother in-law transfer a sum of money through my bank account to my mother (almost double my monthly income) two months ago, which I forwarded same day to her account and it's all reflected in my bank statement. I want to know if I need to explain this to the consular since the sum is not consistent with my monthly income. Thanks

I read somewhere that 'funds parking' in your bank account during last minute is considered as  'mild deception' by consular officers which may lead to a denial.  Please explain why 'funds parking' in your bank account is considered a mild deception?. I see no reason why there is something wrong with this. People are free to do whatever they want with their bank account (e.g could even borrow funds from family) for travel.  I believe visa officers are always looking for several reasons to just deny you a visa.


I mistakenly clicked "Don't trust this website" on a website which has a certificate issue. This is a local website, and the admins are too lazy to fix this issue, but I need to access it anyways.  Now I keep getting an "Secure Connection Failed" error in Firefox.  How can I fix this?

Since installing Firefox 33 a "Secure Connection Failed" error is no longer  using the "I Understand the Risks" button - it's gone!  Is it still somehow possible to ignore certificate errors? (e.g. for lazy use in local environments) Error code: sec_error_invalid_key


I am an Iranian national travelling with British Airways from Tehran, Iran via Heathrow Airport, London to Shanghai, China. I will arrive at LHR on 28th at 11:55am and depart at 14:10pm without changing terminals.  If I need a transit visa, can I obtain one at Heathrow Airport?   I am scared that British Airways have stopped a few people from boarding flights.  Also, do I need a transit visa to enter the UK?  I want to do some sightseeing.  What are the chances of getting past officials using transit without visa concession?

Is there a website or some other way to find out if I need a transit visa for a short stop in the UK on my way somewhere else? Ideally this should give me the answer for all nationalities, and take into account any other visas I may have.


I am running Ubuntu 13.10 and I want to make Caps Lock another Control key. I found that the easiest way was using setxkbmap. But the strange thing is that it resets itself to the default after 1 minute or so, could somebody help me?

I want to change the key bindings on some of the keys on my keyboard.  I want some to run commands and others to activate different keys.  What applications can I use to do this?      Index:       (from within System Settings)             I'm still looking for answers using dconf and any other method.


I'm struggling to find a definition of the Harish Chandra function (usually denoted $\Xi$) online. Could you tell me what it is? There is a definition on wikipedia that I asked about in this post, but I don't understand the notation used there.

Wikipedia defines the Harish Chandra function on a semisimple Lie group to be $$g\mapsto \int_Ka(kg)^\rho dk$$ where $K$ is a maximal compact subgroup, $a(g)$ is the $A$ factor in the Iwasawa decomposition of $g$ and $\rho$ is the Weyl vector (half the sum of the positive roots).  What does it mean to put that vector in the superscript?