Can anyone explain the reason behind the order of adjectives? Why do we say       the small brown antique house   Rather than      the brown small antique house   or      the antique brown small house   I'm familiar with , but I'm looking for some type of reasoning behind this consistency.


Could we allow bold and italics in question titles?

Well, could we? At first thought it seems nice. Has this been discussed before?


I have installed Ubuntu to a 256GB SSD card. My computer has 1TB HDD card. After installing Ubuntu 19.04, the 256GB SSD card is showing but the 1TB HDD card is not showing. Could you help me to fix this problem?


Old Intel Pentium PC: am I an i586? Does Gentoo provide i586 packages? What else am I compatible with?

Greetings Super Users! I've recently commenced revitalizing a very old PC. She's running an Intel Pentium, x86_64. I thought I'd give Gentoo a go because I've found it very appealing and as a Bedrock user I wanted to be able to boot off of Gentoo's init system (initrc, we all know why) as well as bootloader. I've gotten almost halfway through the install ( maybe more like a third :))) ), and now I'm looking for the stage3 files for my PC. I've noticed that though there are builds for i486 and i686. Being genuinely interested in which my PC was, I searched it up and after some light digging found this explanation:   i386 works with any x86 processor (Intel, AMD,etc.), i486 has some performance tun[n]ing. i586 for Pentium and Pentium-MMX i686 for Pentium-Pro, P2,P3, P4, etc.    But in that case Gentoo doesn't support my device?!? Hence, my question: what i version (?) is my Intel Pentium PC? And where are the stage3 files for it? Is it possible to use, say, an i486 for a presumed i586? Thanks in advance, bobbbay EDIT: PC is the ol' .


I have a beamer presentation with a custom style which creates a red bar along the bottom of each slide. When I change the geometry and then revert it with restoregeometry, the red bar is now shifted to the right.  The aim is just to have the picture full width.  \documentclass{beamer}    \mode<presentation>  { \usetheme{myslides}  }  \begin{document}  \begin{frame}[fragile] \frametitle{}  \begin{center} \huge Introduction? \end{center} \end{frame}  \newgeometry{margin=0pt}  \begin{frame}[fragile, plain] \frametitle{} \includegraphics[width=\paperwidth, width=\paperwidth]{picture} \end{frame}  \restoregeometry \begin{frame}[fragile] \frametitle{} \begin{center} \huge Next slide? \end{center} \end{frame} \end{document}   How can I restore back to exactly the state it was in before the newgeometry command?  My question seems related to  as well where there is a similar problem with \restoregeometry in one of the answers.


Algebraic Multiplicity of Eigen Value of Matrix and Its Conjugate

Suppose $A∈M_n(\mathbb{C})$ is a nonsingular matrix and $\bar{A}$ is conjugate of $A$, i.e. entries of $\bar{A}$ is obtained by replace entries of $A$ with their conjugate. Let $\lambda$ be the real negative eigenvalue of $A\bar{A}$. Prove the algebraic multiplicity of $\lambda$ is even.  I've tried it if every entries of $A$ are real, the algebraic multiplicity of $\lambda$ is $0$. But I can't generalize it if some entries of $A$ are not pure real or pure imaginary.


Why does tension not do work in this spool reel problem?

In the solution they are just using the conservation of energy principle, i.e.: $PE_1$ + $KE_1$ = $PE_2 $+$ KE_2$ leaving out any work (smooth surface).  I don't understand how tension doesn't do any work. The rope is attached to the spool and the spool is rotating and sliding.   Is it only because the displacement of tension is 0 because as it unravels, the points of contact change? That's the only logical explanation I can come up with...    EDIT:  "They" are the authors of the textbook. And here's the solution where they use $T_1 + V_1 = T_2 + V_2$, where $T=KE$ and $V=PE$.    EDIT 2:  Full problem statement.


Print small TeX code verbatim and render it

To write some documentation, I would like the ability to define a command such as  \showcase{x^{y}\in\Omega}   which expands to something roughly equivalent to  \verb|x^{y}\in\Omega| & $x^{y}\in\Omega$ \\   so that I can show what the latex code looks like and how does it show on the document.  Now I now that it isn't really possible to use \verb for this because it's really fragile and you can't pass arguments from a macro to it. But, assuming that I'm not trying to write anything crazy in the argument to \showcase (e.g. braces are always balanced, I don't care much if spaces are collapsed, no %'s inside), is there a way to define such a command?  Update  \detokenize does (almost) exactly what I want. Take the following example  \newcommand\showcase[1]{{\ttfamily\detokenize{#1}} & $#1$} \begin{tabular}{cc|cc} \showcase{x^{y}}      & \showcase{\hat{x}, \bar{x}} \\ \showcase{x_{y}}      & \showcase{f\colon X \to Y} \\ \showcase{x'}         & \showcase{\sqrt{x+2}} \\ \showcase{x''_{2}}    & \showcase{2 < x \leq 4} \\ \showcase{A^{1}_{2}}  & \showcase{\frac{a+b}{c+d}} \\ \showcase{3\pi/4}     & \showcase{\int_{0}^{1} x^{2} \,dx} \\ \showcase{x\in\Omega} & \showcase{A \cup B \subseteq C \cap D} \end{tabular}   Which produces the output:    My minor quibbles are that:   The double '' seems to have been collapsed into a " I find mildly annoying the spaces after control sequences. I know why they are there, but could there be a way to remove the space if it is not followed by a letter or number? (Or, conversely, if followed by { or _)


Password request issue when entering sudo

I just installed Ubuntu. I wanted to load a software  to allow me to graphically manage media.   I got a Terminal. I entered the following: sudo apt-get install synaptic The screen prompt demanded a password. I entered my password (not the passphrase) result was   the system did not seem to be allowing keyboard input At least there was no movement of the  cursor and  the system did not recognize my password no matter how many times I entered it.    What am I doing wrong?    Also  I am getting the following when I use the command line   System-Product-Name-Invalid-entry-length-16-Fixed-up-to-11:~$     What's that?   I tried it again using UXterminal from the Dash this time it recognized my password and gave me a Y/n option and I chose Y


Initializing Fields Value in Constructor Versus in Fields Declaration

As we know, in java and some other object-oriented programming languages, fields value can be set in constructor or be initialized in fields declaration statements. I want to know the essential differences between the two ways above. And what conditions I should initialze fields by constructor and what condtions I should't.  Thanks for your help.


How to insert an image with transparent background into PDF?

I set the background of my PDF reader to be light green in order to describe my question. I want to insert an image into the PDF using LaTeX and hope the inserted image become part of the PDF file. Just like this figure:  However, I used the  package and inserted one image (EPS figure) into the PDF. The result looks like this:  How can I insert an image into a PDF file in LaTeX like the first figure? This is not transparency. It is a SVG problem.


Use the Start Screen instead of the Desktop

Before the official release of Windows 10 there seems to have been an option (on the "Taskbar and start menu properties" navigation tab) to uncheck When I sign in or close all apps on a screen, go to the desktop instead of Start in order to use the Start Screen "instead" of the desktop.  Is there any way to do that in Windows 10 today?


HOW TO ACCESS network folders with cmd commands

how do i access my network folders in cmd window. when i'am trying to acces as  cd \ computername. then it flashes an error message as "CMD does not support UNC paths as current directories"


grub rescue>insmod normal error:unknown file system.  grub rescue>  What should Ι do when my laptop shows this error?


Cannot suggest retag-only edit because "edits must be at least 6 characters"

I was trying to suggest a retag of  on Seasoned Advice, but the system won't let me; I get the familiar message     Edits must be at least 6 characters; is there something else to improve in this post?   In general, that's not true for retagging; if you don't change the question body at all, it should work. I suspect the logic checking the edit is thrown off guard because of the title warning:     The question you're asking appears subjective and is likely to be closed       I found , but I cannot find any evidence (in SEDE) for invisible characters being present in the question's source. Also, that's supposed to be .


Different behaviors of 'is' operator when comparing variables with same int values

I'm playing with the 'is' operator in the interactive shell when I encountered an odd behavior with the below code:  It goes as expected at first:  >>> x = 11  >>> y = 11  >>> x is y  True   But when I tried this one:  >>> x = 987456  >>> y = 987456  >>> x is y  False   After further tries using id() function, I noticed that integers >256 points on the same object while others are not. I also noticed that this behavior only occurs in the python interactive shell. What's with this behavior?


I am seeking a proof for the following statement of the Parseval identity:     If $f$ is a holomorphic function defined on the ball $B(0,r)$, with power series $f(z) = \sum_n a_n z^n$, then $$2 \pi \left( \sum_n |a_n|^2 r^{2n} \right) = \int_0^{2\pi}|f(re^{it})|^2dt.$$   I have seen some proofs of other statements of Parseval identity (specifically using Fourier series), but not of this. I guess I'm looking for one of two possible answers:  1) A proof of the quoted result above (or an outline thereof), or  2) A reference to a standard proof of some statement of the Parseval identity, along with some hints as to how to obtain "my" statement of it from the other (having trouble seeing how to transition).  Thanks in advance for any help!


Why does this object periodically turn itself?

See below gif image taken from .    Or see  about 30 sec in.    Is this a real effect?  Why does it seem to turn periodically? Can it be explained by classical mechanics alone? Is there a simple equation that models this behaviour?


Create new tcolorbox environment programmatically

I want to create new numbered tcolorbox environments, so that every group has its own  numbering. I can do this by following code. \usepackage[most]{tcolorbox} \documentclass{article} % group of alerts \newtcolorbox[auto counter, number within=chapter]{alertbox}[1][]{     colback=red!10!white,     title=\textbf{Alert~\thetcbcounter :} {[#1]~}, } % group of notes \newtcolorbox[auto counter, number within=chapter]{notebox}[1][]{     colback=blue!10!white,     title=\textbf{Note~\thetcbcounter :} {[#1]~}, } \begin{document}    \begin{alertbox}[Food] % Alert 1.1: Food         Food is ready    \end{alertbox}    \begin{alertbox}[Drinks] % Alert 1.2: Drinks         Drinks are ready    \end{alertbox}    \begin{notebox}[Food] % Note 1.1: Food         Caution! Food is hot.    \end{notebox}    \begin{notebox}[Drinks] % Note 1.2: Drinks         There is Cola in Drinks!    \end{notebox}  \end{document}  But, this leads to code repetition. I'm trying to avoid this by creating a command that constructs tcolorbox environment. \newcommand{\declarenumberedbox}[3] {    \newtcolorbox[auto counter, number within=chapter]{#1}[1][]{        colback=#2,        title=\textbf{#3~\thetcbcounter :} {[                            ]~},                                           %% custom title must be here   %%                                           %% what should be filled here? %%    } } %% approximately how I want my code to look like  %% (or some equivalent ways to achieve this). \declarenumberedbox{alertbox}{Alert}{red!10!white} \declarenumberedbox{notebox}{Note}{blue!10!white}


How to get value on a single row with XPath?

I have a user table, email table and a relational email table. Some users have more than one email addresses.  When Use  select U.Id,U.Name,E.Name from RelationalEmail AS RE INNER JOIN Email AS E ON E.Id = RE.EmailId INNER JOIN User AS U ON U.Id=RE.userId   Of course, I get the result like this:  UserId    Name     Email 1         Olcay    abc@.com 1         Olcay    acc@.com 2         John     jhn@.com 2         John     hnJ@.com   But I don't want repeat of users,  I try to get a result like:  UserId    Name     Email       1         Olcay    abc@.com, acc@.com 2         John     jhn@.com, hnJ@.com   My Person Table:    UserId    Name           1         Olcay         2         John    My Email Table:  EmailId    Name    7         abc@.com    8         acc@.com    9         jhn@.com    10        hnJ@.com   My RelationalEmail Table:  Id   userId  EmailId   1      1     7   2      1     8   3      2     9   4      2     10   My teacher said I should do that with XPath. But I don't know XPath. I searched that but I couldn't find an answer for my question or I couldn't understand.  Thanks in advance


I am trying to understand use of :. I have below example code. I am not getting what the last line is doing. Please explain. Also please share how or when to use :  listoflists = [] list = [] for i in range(0,10):     list.append(i)     if len(list)>3:         list.remove(list[0])         listoflists.append((list, list[0])) print (listoflists)  print (listoflists[:][0][1])#print y values only for the first batch, : for all batches  print (listoflists[0][1]) print(listoflists[:])


ClassCastException Object cannot be cast to

I don't understand why I get ClassCastException on below code in line:  for(int i = 0; i < k.t.length; i++)   So problem is that in method addElement I make replacing of array elements by objects with type T. In my opinion in array should be objects with type T. And compiler doesn't protest for that.  But in run-time JVM cannot cast despite in array is really objects with type T (in case below String), why JVM cannot use polymorphism?  But when I change the  T[] t; to Object[] t;  and remove cast in constructor it run correctly without any errors, why?  public class MyCollection<T> {      T[] t;      MyCollection( int size){         t = (T[]) new Object[size];     }      boolean addElement(T e, int i){                 if(i < t.length){             t[i] = e;             return true;         }         return false;                 }      public static void main(String[] ss){          MyCollection<String> k = new MyCollection<String>(3);          k.addElement("a",0);         k.addElement("b",1);         k.addElement("c",2);          for(int i = 0; i < k.t.length; i++)             System.out.println(k.t[i]);               //for(String s : (String[])k.t)         //    System.out.println(s);             } }


Proving the function $f(x)=x^n$ is continuous

I want to prove that given $y\in \mathbb R, n\in \mathbb N, \epsilon >0$, there exists $\delta>0$ such that for any $u\in\mathbb R$, $|u-y|<\delta$ implies $|u^n-y^n|<\epsilon$. It is not permitted to use any notion of product rule of limits, continuous function etc. Only a pure epsilon-delta argument has to be used.   So here's my attempt:  We proceed by induction. For $n=1$, clearly $\delta=\epsilon$. Assume the result true for all $k\le n-1$. Now fix $\epsilon>0$ and consider $|u^n-y^n|=|u-y||u^{n-1}+u^{n-2}y+\cdots +y^{n-1}|$. The term $|u^{n-1}+u^{n-2}y+\cdots +y^{n-1}|$ seems to be the issue. I need to bound this quantity in terms of $\epsilon$ by using the induction hypothesis. Now I am thinking of something like $|u^{n-j}|<\frac{\epsilon}{n}+|y^{n-j}|$ but cannot seem to get a coherent argument.


Disk usage on Ubuntu - Find the largest Sized Directory or File

Is there a way to find the which directory or file is taking up the largest space on the Ubuntu Server?   I tried df -h  root@s-production:~# df -h Filesystem      Size  Used Avail Use% Mounted on udev            2.0G  4.0K  2.0G   1% /dev tmpfs           396M  364K  395M   1% /run /dev/vda1        40G  8.1G   30G  22% / none            4.0K     0  4.0K   0% /sys/fs/cgroup none            5.0M     0  5.0M   0% /run/lock none            2.0G     0  2.0G   0% /run/shm none            100M     0  100M   0% /run/user


Safari homepage hijacked and I can't change back

imac 2011 10.10.5  Safari had homepage hijacked and I can't change it back to google.com.  When I go to Safari preferences and try and change, it just immediately goes to www.rack-search.com/....  I tried deleting all the com.apple.safari.plists in library.  Can you help?


In Objective C I know that the asterisk * works as a pointer to creating/defining/initializing a pointer to an object.   But what about when the asterisk is inside a parenthesis?  It is the same   (NSString*) name;  than  NSString *name;  Second question  If I declare in the @ interface the methods without using @property way i do    - (void) setName:(NSString*) newName;   - (NSString*) name;   - (void) setSupervisor:(Employee*) newSupervisor;   - (Employee*) supervisor;   - (void) setSalary:(int) newSalary;   - (int) salary;   But if i use @property I do     @property (nonatomic, readonly) int employeeNumber;    @property (nonatomic, retain) NSString *name;     @property (nonatomic, retain) Employee *supervisor;    @property (nonatomic, assign) int salary;   Why the parenthesis in NSString, int, Employee disappeared? Why the asterisk move from (NSString*) name; to NSString *name  Thank you  CL


I have a button:      	   and jQuery code:  $(function(){   $(".separa_conto").click(function() {     var conto = $(this).data('conto');     var nuovoConto = conto + 1;     alert(conto);     $('#showAddeb_conto_'+ conto).removeClass('hidden').show('slow');     $('#showAddeb_conto_'+ conto).append('
	Sogg	1000
');     $('.rigaconto').append('');      var table = $('

').attr('id','showAddeb_conto_'+ nuovoConto).addClass('table table-hover table-bordered hidden');     var row = $('
	Further account
');     table.append(row);      $('#tabelle_conti').append(table);    }); });   but if I click twice class "NewAccount" doesn't appear second table. What is my mistake?


What, in simplest terms, is gauge invariance?

I am a mathematics student with a hobby interest in physics. This means that I've taken graduate courses in quantum dynamics and general relativity without the bulk of undergraduate physics courses and sheer volume of education into the physical tools and mindset that the other students who took the course had, like Noether's theorem, Lagrangian and Hamiltonian mechanics, statistical methods, and so on.  The courses themselves went well enough. My mathematical experience more or less made up for a lacking physical understanding. However, I still haven't found an elementary explanation of gauge invariance (if there is such a thing). I am aware of some examples, like how the magnetic potential is unique only up to a (time-)constant gradient. I also came across it in linearised general relativity, where there are several different perturbations to the spacetime metric that give the same observable dynamics.  However, to really understand what's going on, I like to have simpler examples. Unfortunately, I haven't been able to find any. I guess, since "gauge invariance" is such a frightening phrase, no one use that word when writing to a high school student.  So, my (very simple) question is: In many high school physics calculations, you measure or calculate time, distance, potential energy, temperature, and other quantities. These calculations very often depend only on the difference between two values, not the concrete values themselves. You are therefore free to choose a zero to your liking. Is this an example of gauge invariance in the same sense as the graduate examples above? Or are these two different concepts?


I'm using php5.6 and something is wrong with the code below      $a = (float)4.2;     $b = (float)1.4*3; // But 2.1*2 works       if ($b === $a) {         die("Equal 1");     }     else if ($b == $a) {         die("Equal 2");     }     else {         die("Not Equal");     }   The result always is "Not Equal"  Many thanks!!!


Why doesn't new in C++ return NULL on failure

Why doesn't new return NULL on failure? Why does it throw an exception only on failure?  As it returns a pointer to the object on successes, why not on failure? Is there any specific reason for this behaviour?


I have to prove that the space of continuous functions on a (I suppose closed) interval $I$ (let's say $[0,1]$) with distance $d(f,g)$ $=$ $\int _I$ $|f-g|$ is not complete.  The Cauchy function to be used is $f_n$ = $n$ in [$0$, $e$ $^-$ $^n$] and $\log(1/x)$ in [$e$ $^-$ $^n$, $1$]  Why is it not complete though? Thanks!


miktex with pdfpages - first page repeated instead of actual pages of original pdf

I have the following problem with the pdfpages package. After the update of my MiKTeX installation, the following command  \includepdf[pages=-,pagecommand={},offset=15pt 15pt,width=175mm]{test.pdf}   does no longer include all pages of the pdf file, but only repeats the first page of that pdf as often as there are pages in the pdf file.  I have had a second computer where I updated the following packages:    Before the update, that second computer included the pdf pages as expected, but after the update, it only included the first page of the pdf file as often as there are pages in the pdf file.  Any help would be greatly appreciated.


Southern Magician feat as prerequisite for arcane/divine casters

I have trouble understanding the details of the full scope of the Southern Magician feat:  Southern Magician [General] Your magical studies in Mulan lands have taught you spellcasting techniques unknown in the north that blur the line between arcane and divine magic. Prerequisite: Mulan human, ability to cast 2nd-level spells. Benefit: Once per day per two spellcaster levels, you can cast a divine spell as an arcane spell, or vice versa. This enables you to bypass arcane spell failure due to armor, or gain additional benefit from spell that functions differently for a divine caster instead of an arcane caster, such as true seeing or magic weapon. Spells changed with this feat are often confusing to whose who haven’t studied Mulan magic. Spellcasters who don’t have this feat suffer a –4 penalty on attempts to counterspell or dispel this spell, and they must succeed at a caster level check (DC 11 + spell level) to detect the spell with detect magic. The actual source of the spell’s power doesn’t change, nor does its means of preparation. You are merely weaving the strands of magic together in an unconventional way that makes the spell behave somewhat differently.  My questions would be:  Does a pure wizard with this feat qualify for Theurge type classes, as he can cast divine spells at the same level  (eg: Geomancer or Mystic Teurge after level 3)? [this question is moved to a separate question]


How to stop beta websites indexing in Google Search?

I want stop my beta.example.com being indexed by search engines, because it can generate duplication issue.


Python class variables scope not as per documentation

As per : "Generally speaking, instance variables are for data unique to each instance and class variables are for attributes and methods shared by all instances of the class"  >>> class Dog: ...   kind='canine' ...    ...   def __init__(self, name): ...     self.name = name ...  >>> d = Dog('Fido') >>> e = Dog('Buddy') >>> d.name 'Fido' >>> e.name 'Buddy' >>> d.kind 'canine' >>> e.kind 'canine' >>> d.kind='cat' # changed supposedly shared variable to cat >>> d.kind # OK here 'cat' >>> e.kind # Not expected output (should be cat as per documentation) 'canine'   Am I missing something?


Accidentally ran chown -R / and now mail queue not being delivered

EDIT:   BTW, everything else including all websites on the server are running fine except that mail queue in whm is not automatically being delivered.   What directory would I need to change permissions on just to fix mail sending again?  So last night I accidentally typed the following command as root via ssh and changed some permissions to account 'userx':  chown -R userx /  That permission change command only ran for about 5 seconds and I quickly realized my error and forced stopped it.  Today the mail queue is not being delivered unless I manualy force deliver all mail in the queue in whm.  I don't know if that was the cause of this issue but a few minutes ago I ran the following command to try fix it and let that run for about 5 seconds then force stopped it.  chown -R root /  However, the problem with the mail queue is still there.    Can you please let me know if in fact that accidental few seconds of changing of permissions in / could be the problem and how can I check which essential directories and files actually got change and need to be set back to root permissions?  Thank you


Proving $\int_0^1\frac{\log (1-x)}{x}\mathrm dx=-\frac{\pi^2}6$

It is a well known fact that $\displaystyle\sum_{k=1}^{\infty}\frac1{k^2}=\frac{\pi^2}6$. I wanted to prove this using elementary techniques. By doing some easy algebra, I found it was sufficient to prove that $$\int_0^1\frac{\log (1-x)}{x}\mathrm dx=-\frac{\pi^2}6.$$ (By defining a function $f(x)=\displaystyle\sum_{k=1}^{\infty}\frac{x^k}{k^2}$ and doing some integration.)  I have been trying to evaluate this integral using secondary school techniques (i.e., substitution or partial integration) but I didn't achieve much.  Some approaches:  1. It's not hard to see that $$\int_0^1\frac{\log (1-x)}{x}\mathrm dx=\int_0^1\frac{\log x}{1-x}\mathrm dx$$ It's not much, but the logarithm looks nicer now.  2. Also, since we want $\pi$ to appear, a trigonometric substitution might be helpful. I tried subsituting $x=\sin^2t$ which gives $$\int_0^{\frac\pi2}4\log(\cos t)\cdot \cot t\;\mathrm dt$$ or, using the second form, $$\int_0^{\frac\pi2}4\log(\sin t)\cdot \tan t\;\mathrm dt$$ Another remark: $\int\tan a=-\log|\cos a|$ might help, because $\log|\cos a|$ appeared in the integral. But I dont's see immediately how to use this. (Absolute values within the logarithm are unnecessary because $\sin t,\cos t\geq0$ in this case.)  3. Setting $x=\cos 2t$ gives $$-2\int_0^{\frac\pi2}(\log2+2\log(\sin t))\tan 2t\;\mathrm dt$$ by using the identity $\frac{1-\cos2a}{2}=\sin^2a$. And since, by symmetry, $$\int_0^{\frac\pi2}\tan 2t\;\mathrm dt=0$$ the integral is just $$-4\int_0^{\frac\pi2}\log(\sin t)\tan 2t\;\mathrm dt$$ which looks quite nice.


How can I use jQuery for a growing #of selectors?

In my webpage, a user can press a button which copies the selection fields to make a sandwich to another line. I managed to change the IDs for each new selection field as so bread1, bread2, bread3 ...  In jQuery how can I refer to all of the selection fields in an event? I've tried this below, but it does not work for the newly created select fields. $("select[id^='bread']").change(function({     ... });  I have also tried adding all new selects as DOM objects into an array and tried to make a jQuery object off that, but jQuery select statements don't read arrays.


I'm looking to create a cursor that's a red circle. I was thinking maybe there's a way I could edit a cursor's background colour and then add a border radius to create a circle.  Is this possible?   Note: I do not want to use something like cursor: url(img.jpg), I want to colour the cursor just by css.


Computing A Multivariable Limit: $\lim_{(x,y) \to (0,0)}\frac{2x^2y}{x^4 + y^2}.$

Please help me in computing the following limit. $$\lim_{(x,y) \to (0,0)}\frac{2x^2y}{x^4 + y^2}.$$ This will be my first attempt in computing a limit involving 2 variables. Is this a part of multivariable calculus as it contains more than one variable? How can I interpret this geometrically?  Thank You


I'm trying to find a proof of this:     The group  $\langle\mathbb{Z}_n,\oplus\rangle$ is cyclic for every $n$, where $1$ is a generator. The generators of the group $\langle\mathbb{Z}_n,\oplus\rangle$ are all $g \in \mathbb{Z}_n $ for which $\gcd(g,n)=1$, as the reader can prove as an exercise.   It is perfectly clear that $1$ generates all $\mathbb{Z}_n$, but I can't get myself to understand the second part or find a way to prove it. Thanks.


I am struggling with increasing my stackoverflow reputation from one.  I coming at this with the assumption that the reputation system has been designed with the intention of making it possible to measure individuals' contributions to the community. I am completely in favour of such a mechanism.  As far as I can tell, at a reputation of one, the only options for my raising reputation is to either ask or answer a question.  Surely, it's not that hard to ask or answer a question? Actually I think it is because, unless I want to duplicate an existing question or answer, or to provide a rushed or incomplete answer, searching stackoverflow for existing content is usually sufficient.  I do want to contribute as I feel the urge to pay back to the community; however I am finding that my low reputation is preventing me from doing this. For instance, whenever I try to vote up an answer, I am told my reputation is too low.  So far I have been resisting asking bogus questions and getting friends to answer them; however, unless I find a legitimate way of increasing my reputation, I suspect that I will eventually fold.  So my question is, how do I raise my reputation in a way that does not abuse the intention behind reputations!  Thanks.  P.S. Ironically, moments after asking this question, a previous answer I had posted was accepted and I was launched to 11 rep. It looks like I am out of the bootstrapping zone and I can start to contribute to the community. Thanks for the answers and comments folks.


How to start UX design? Should I attend a boot-camp or self-teach? If self-teach, what are some good resources out there for me to use?


How can I get around "error 0x80070522" when creating files in the root of the C drive (C:\)?

One of our customers has just found a problem when trying to create a file on the root of the C Drive (C:\), on a Windows 7 Professional PC.  I know they shouldn't be keeping files here, but there is a valid reason in this case, so I've relaxed the security on C:\ by giving the users group users modify permissions.  Before I relaxed the security, the user was receiving access denied, but now they are receiving the message:     An unexpected error is keeping you from creating the file. If you continue to recieve this error, you can use the error code to search for help with this problem. Error 0x80070522: A required priviledge is not held by the client.    for this suggests that it is caused by UAC, but how can I get around this when the user doesn't have admin rights on their PC?


How can I align equation in a big brace?

I want to write the following equation:  For that I wrote a code: \RequirePackage{fix-cm} \documentclass[twocolumn]{svjour3}    % \smartqed  % flush right qed marks, e.g. at end of proof % \usepackage{graphicx} \graphicspath{ {./images/} } \usepackage[caption=false,font=footnotesize]{subfig} \usepackage{mathtools} \usepackage{nccmath} \usepackage{booktabs} \usepackage{float} \usepackage{multirow} \usepackage{makecell} \usepackage[caption=false,font=footnotesize]{subfig} \usepackage{varwidth} \usepackage{placeins} \usepackage{textcomp} \usepackage{natbib} \setcitestyle{aysep={}}  \bibliographystyle{spbasic} \begin{document}  \begin{align*} w_{i} =  \Bigg\{1;\hspace{0.25cm} if\hspace{0.25cm} 0.25N \leq i \leq 0.75N \\                             0.5;\hspace{0.25cm} otherwise\\ \end{align*}  \end{document}  The output:


“Cannot find file” error when running biber (2)

I'm writing my thesis using biblatex and biber for the references. When I compile I get the following error message: ERROR - Cannot find 'C:/Users/dvale/Documentos/3_References/References.bib'!  I had a long conversation with @moewe in the comments of  question, traying to solve this issue. Apparently anything is wrong, but the MWE still not working in my computer. Does anyone else have any information to help me fix this? \documentclass[12pt,a4paper]{article} \usepackage{biblatex} \addbibresource[location=remote]{C:/Users/dvale/Documentos/3_References/References.bib} \begin{document} Example \cite{Ballot2014} \printbibliography \end{document}  Informations: The .bib file was created with JabRef with UTF-8 encoding The .bib file has 362 entries The .bib file size is 185 KB I'm using TeXstudio The default bibliographic tool is biber The default compiler is pdflatex When I put the .bib file into the working directory, the MWE run perfectly #With References.bib into the MWE working directory \documentclass[12pt,a4paper]{article} \usepackage{biblatex} \addbibresource{References.bib} \begin{document} Example \cite{Ballot2014} \printbibliography \end{document}  I already tried to clear the biber cache This problem starts when I change my notebook I really need to use a single bib file for all my documents, instead of having a bib file for each document, since the references are all about the same subject and I already have written documents that lose their references.


About 1/3 of the time that I boot my laptop, I get an error message that says  Error: Malformed file. Press any key to continue...   I press a key, and then my computer boots up and I can't discern any negative effects.  It's kind of disconcerting, and does delay the boot process.  How do I resolve this error and ensure my system is stable?


Let $f$ be a real valued function on $\mathbb{R}$. Consider the functions $$ w_j(x) := \sup\left\{\vert f(u) − f (v)\vert : u,v \in \left[x−\frac{1}{j},x+\frac{1}{j}\right]\right\} $$ where $j$ is a positive integer and $x\in\mathbb{R}$.  Then define $$ A_{j,n}: = \left\{x \in \mathbb{R}: w_j(x)<\frac{1}{n}\right\},\qquad n=1,2,\ldots  $$ and $$ A_n:=\bigcup_{j=1}^\infty A_{j,n}, \qquad n = 1,2,\ldots $$ Now let $C=\{x \in \mathbb{R}:f \text{ is continuous at }x \}$. Express $C$ in terms of the sets $A_n$.  I am totally confused. Please help me.


No account of type com.salesforce.androidsdk found

I'm trying to build an Android test application integrated to the SalesForce platform. I have downloaded the SDK from , and imported it to my workspace. Everything works fine except my test app, even the  they have provided along with the SDK work without problem. As a first step, what I tried was to clone the basic features (just login as of now) from the RestExplorer app. The following are my important files.  public class Home extends Activity {  private PasscodeManager passcodeManager; private RestClient client; private TokenRevocationReceiver tokenRevocationReceiver;  RestClient getClient() {     return client; }  @Override protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);      passcodeManager = SalesforceSDKManager.getInstance().getPasscodeManager();     tokenRevocationReceiver = new TokenRevocationReceiver(this);     setContentView(R.layout.activity_home);  }  @Override  public void onResume() {     super.onResume();     registerReceiver(tokenRevocationReceiver, new IntentFilter(ClientManager.ACCESS_TOKEN_REVOKE_INTENT));           if (passcodeManager.onResume(this)) {   // Bring up passcode screen if needed         String accountType = SalesforceSDKManager.getInstance().getAccountType();   // Login options         new ClientManager(this, accountType, SalesforceSDKManager.getInstance().getLoginOptions(), SalesforceSDKManager.getInstance().shouldLogoutWhenTokenRevoked()).getRestClient(this, new RestClientCallback() {    // Get a rest client             @Override             public void authenticatedRestClient(RestClient client) {                 if (client == null) {                     SalesforceSDKManager.getInstance().logout(Home.this);                     return;                 }                 Home.this.client = client;                           }         });     } }  @Override protected void onPause() {     passcodeManager.onPause(this);     unregisterReceiver(tokenRevocationReceiver);     super.onPause(); } }   I have added the permissions as required  <permission android:name="com.salesforce.samples.restexplorer.C2D_MESSAGE"     android:protectionLevel="signature" />  <uses-permission android:name="com.salesforce.samples.restexplorer.C2D_MESSAGE" /> <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/> <uses-permission android:name="android.permission.GET_ACCOUNTS"/> <uses-permission android:name="android.permission.MANAGE_ACCOUNTS"/> <uses-permission android:name="android.permission.ACCOUNT_MANAGER"/>   And extended the application object to give a call to init();  public class MyApp extends Application { @Override public void onCreate() {     super.onCreate();     SalesforceSDKManager.initNative(getApplicationContext(), new KeyImpl(), Home.class); } }   Now, I'm getting the error in my Android debug log. The log as I see is attached below. It keep the activity restarting till I forcefully kill the application.  11-08 15:56:23.883: I/ClientManager:getRestClient(9334): No account of type com.salesforce.androisdk found 11-08 15:56:23.898: W/AccMgrCallback:run(9334): android.accounts.AuthenticatorException: bind failure 11-08 15:56:23.898: W/AccMgrCallback:run(9334):     at android.accounts.AccountManager.convertErrorToException(AccountManager.java:1726) 11-08 15:56:23.898: W/AccMgrCallback:run(9334):     at android.accounts.AccountManager.access$400(AccountManager.java:144) 11-08 15:56:23.898: W/AccMgrCallback:run(9334):     at android.accounts.AccountManager$AmsTask$Response.onError(AccountManager.java:1572) 11-08 15:56:23.898: W/AccMgrCallback:run(9334):     at android.accounts.IAccountManagerResponse$Stub.onTransact(IAccountManagerResponse.java:69) 11-08 15:56:23.898: W/AccMgrCallback:run(9334):     at android.os.Binder.execTransact(Binder.java:388) 11-08 15:56:23.898: W/AccMgrCallback:run(9334):     at dalvik.system.NativeStart.run(Native Method)   Do anyone have any idea about this isse? It is such a basic app, I was not expecting anything unusual. Did I do anything wrong in my app?


Find a non-negative function on [0,1] such that $t\cdot m(\{x:f(x) \geq t\}) \to 0$ that is not Lebesgue Integrable

Problem:  Find a non-negative function $f$ on $[0,1]$ such that $$\lim_{t\to\infty} t\cdot m(\{x : f(x) \geq t\}) = 0,$$ but $f$ is not integrable, where $m$ is Lebesgue measure.  My Attempt:  Let $f(x) = \frac{\chi_{(0,1]}}{\sqrt{x}}$. Then,  \begin{align*} \lim_{t\to\infty} t\cdot m(\{x \in [0,1]: f(x) \geq t\}) &= \lim_{t\to\infty} t \cdot m(\{x\in (0,1]: 1/\sqrt{x} \geq t\})\\ &=\lim_{t\to\infty} t \cdot m(\{x\in (0,1]: x \leq (1/t^2)\})\\ &= \lim_{t\to\infty} t \cdot m((0, (1/t^2)))\\ &= \lim_{t\to\infty} \frac{t}{t^2} = 0. \end{align*}  However, $f(x)$ is integrable over this interval. I have tried functions looking like $f(x) = 1/x^p$ but I cannot find any that will work here. There is a hint that says there is a monotonic function that fits this description.    Also, does anyone know of a list of non-Lebesgue integrable functions on $[0,1]$? I feel as though I could use this for many counterexamples if one were to exist. Thanks!


Assistant professor vs Associate professor

What's the difference between an associate professor and an assistant professor?  What can one of them do that the other can't? and which is a higher level? can any of them supervise a PhD student?


I recently make a WebView App for my website and i have a few versions of it but i like this the best. On the tutorial guy video, it all works 100% Great but on mine tho, theres tons and tons of errors that i had resoved. Now one left, the app crashes every single time i tried to start it. It will show for 2 seconds and then closed.  Here's the stack trace :  08-21 20:32:52.060 3149-3149/app.gonenjoy.com E/AndroidRuntime: FATAL EXCEPTION: main                   Process: app.gonenjoy.com, PID: 3149                   java.lang.NullPointerException                   at app.gonenjoy.com.MainActivity$MyWebviewClient.onPageFinished(MainActivity.java:160)                   at com.android.webview.chromium.WebViewContentsClientAdapter.onPageFinished(WebViewContentsClientAdapter.java:449)                   at com.android.org.chromium.android_webview.AwContentsClient$AwWebContentsObserver$1.run(AwContentsClient.java:73)                   at android.os.Handler.handleCallback(Handler.java:733)                   at android.os.Handler.dispatchMessage(Handler.java:95)                   at android.os.Looper.loop(Looper.java:146)                   at android.app.ActivityThread.main(ActivityThread.java:5641)                   at java.lang.reflect.Method.invokeNative(Native Method)                   at java.lang.reflect.Method.invoke(Method.java:515)                   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1288)                   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1104)                   at dalvik.system.NativeStart.main(Native Method)   Any help is apriciated.  Tested on Bluestacks & Samsung galaxy young 2 Android Studio v2.3


In the movie Die Hard, John McClane (Bruce Willis) says the line "Yippie Ki Yay".  What does this mean?


jQuery once callback function is not called

I'm struggling with the once function. The once callback function is not called. I'm trying to use like this:  (function ($, Drupal){   Drupal.behaviors.my_module = {     attach: function (context, settings) {       console.log('this runs');        $('.my_selector', document).once('special-mark', function() {         console.log('this never called');       });        console.log('this also called');     }   } })(jQuery, Drupal);   In the library file I use the following:  dependencies:   - core/jquery   - core/jquery.once   - core/drupal   There's no a single error in the console. It's just simply not called the callback... How can I make it work?  Drupal: 8.8.4 jQuery: 3.4.1


Is it possible to move win10 installation?

I have my win10 and various apps installed on my HDD. And I have a new SSD. Is there a way to safely move win10 to the SSD? Or the only way is to install it again?


zsh Interpret/ignore commands beginning with '#' as comments

In bash, if I type a command beginning with a '#', bash ignores it as a comment.  Ie, the following is ignored at the bash prompt:  > # Hi there!   Whereas in zsh:  > # Hi there ! zsh: bad pattern: #   How can I ask zsh to do the same?  This is incredibly useful to "store" commands that you want to run later, or to chat when using a shared tmux/screen session.  I am using ''


Ubuntu 14.04 LTS wired internet extremely slow

My wired internet is running extremely slow after installing Ubuntu 14.04 on my desktop. my normal internet speed (Windows) using speedtest.net is around 25 mbps, Ubuntu is pulling in 0.5 mbps tops.  I've found lots of issues with the 'Realtek RTL8111 Ethernet Interface' I've got, they all say to change the drivers to r8168 (which I've done) or change the IPv6 to ignore (also done) but my internet is still running extremely slow. I've tried everything I've been able to find online and rebooted multiple times along the way but all to no avail. I don't have much experience with Linux, but am eager to learn.   What do I need to do to fix this problem?


Slide two edge loops away from each other

I've been looking for this feature in Blender, either upon the time of creation using Edge Cut and Slide or afterwards, in just editing the mesh. I'd like to know if it's possible to evenly slide two edges away from one another in Blender?  Here's a picture of what I'd like to be able to do:    Thanks upfront!!


Behringer Pro Mixer DX 500 Needs to match new power supply adapter

I'm quite unfamiliar with the electrical side of things, so I'd appreciate it a lot if I can get some basic help. I have a Behringer Pro Mixer DX 500 at home which would be used mostly in Bulgaria - where the voltage is at 220V. It came without a power supply adapter, in the photo (where it's a bit blurry) it says: POWER SORCE: 2 * 19 VAC 30W Here's also the manual for the mixer if it's helpful:   Turned out a power supply adapter is close to impossible to find quickly on the web and in a bit of a rush, I purchased the following from the US:  The model (which is cropped out in the picture) is MXUL2 specifically. Only later I realized it says 2 * 17.5 VAC. So I wanted to ask if that's gonna be in any way a problem and, in case it is, can I somehow compensate by purchasing a precise Down Voltage Transformer (which I need to get anyway for transforming 220 V to 115V)? Even if the 2 * 17.5 VAC discrepancy wouldn't be a problem (I so hope it wouldn't), feel free to suggest a respective Down Voltage Transformer, if you have something in mind that is a good choice on the low price end of things. Thanks a lot!


How to set up a cron job to run every 10 minutes?

I have a python script, and i'd like to make it run every 10 minutes, how can i do this? Thanks in advance.


Including section titles in fancyhf headers

I would like to include the section name of the page's displayed section in my header tags in the fancyhdr package, something like  \fancyhf[HR]{SECTION NAME} \fancyhf[HL]{SUBSECTION NAME}   How can I go about doing this?


Good book for self study of a First Course in Real Analysis

Does anyone have a recommendation for a book to use for the self study of real analysis? Several years ago when I completed about half a semester of Real Analysis I, the instructor used "Introduction to Analysis" by Gaughan.   While it's a good book, I'm not sure it's suited for self study by itself.  I know it's a rigorous subject, but I'd like to try and find something that "dumbs down" the material a bit, then between the two books I might be able to make some headway.


Using the pumping lemma to deduce that the language consisting of palindromes is not regular

Given an alphabet $\Sigma$ (of size at least $2$) let $L$ be the language consisting of words of the form $a^kb^k$ with $k\in \mathbb{N}$ and $a,b\in \Sigma$. Then for any $p\in \mathbb{N}$ pick $a\neq b\in \Sigma$ and we have $a^pb^p\in L$.  If we write $a^pb^p=xyz$ with $|y|\geq 1$ and $|xy|\leq p$ then $y=a^i$ for some $i\geq 1$ and $xy^2z=a^{i+p}b^p\notin L$.  From  we may conclude that $L$ is not regular. Let $L'$ be the language consisting of palindromes: that is strings on $\Sigma$ which are invariant under reversing.  Is there a proof (similar to the one above for $L$) that $L'$ is not regular using the pumping lemma?


Calculate $$\sum_{k=1}^{\infty}\frac{1}{2^{k+1}-1}.$$    I used Wolfram|Alpha to compute it and got it to be approximately equal to $0.6$. How to compute it? Can someone give me a hint or a suggestion to do it?


For example,any "naked" code, i.e.:  IF ($_POST) then....,   runs directly, before any WP action.  for example, this runs later (even with point 1):  add_action('init','my_function',1);   I want to execute my code before any WP action starts. Which hook executes at first?


Should pressing Ctrl+C with nothing selected really clear your clipboard / copy the whole line?

It seems a bit counter-intuitive to me that in many text editors / IDEs, pressing Ctrl+C with nothing selected, clears your clipboard, or replaces it with whatever is on the same line as the caret.  Is there a standard for dealing with this behaviour?


What are the evil posts that the community bot downvotes?

The  mentions:     Own downvotes on spam/evil posts that get permanently deleted   Should the correct wording be "inappropriate" instead of evil? What does an evil post mean? Please, can someone provide an example?


Are we living in a false vacuum? Is there any way to tell?

I was thinking of the noted 1980 paper by Sidney Coleman and Frank de Luccia--"Gravitational effects of and on vacuum decay"-- about metastable vacuum states that could tunnel to a lower energy "true vacuum" with catastrophic results. I suspect the answer is that if our vacuum is a false one, we wouldn't "see" the true one til it hit us.


I've been looking for the right object to query using the API to get the used/total amount per license type, but I'm not quite sure which one holds this information.    PermissionSetLicense seems to contain Used/Total values, but it is related to Permission Sets and returns 0 results when I query it.     UserLicense seems related to License too, but it doesn't contain field related to this.     Am I missing something?


Recurring Events Lightning - Repeat field is not writable. How to use this field in custom lightning page?

I am trying to create a bulk action on recurring events. Isrecurrence2 field is not writable in the controller.  How to create recurring events in custom lightning pages.  The image is from my controller class. I want to set the field false intially.


Improper integral of $\int_0^\infty \frac{e^{-ax} - e^{-bx}}{x}\ dx$

For $a>b>0$, calculate    $$\int_0^\infty \frac{e^{-ax} - e^{-bx}}{x}\ dx$$  My try : By Taylor series, $$\int\ \frac{e^{-ax} - e^{-bx}}{x} \ dx=  \sum_{n=1}^\infty \frac{[\ (-a)^n -(-b)^n\ ]}{n}\frac{x^n}{n!} +C $$  Note that from ratio test, this series converges absolutely for $x\in [0,\infty)$. So give me a hint. Thanks  Seocond Try : Recall $$ \Gamma(t) = \int_0^\infty s^{t-1}e^{-s}\ ds\ (t>0)$$  So $$\Gamma(t) = a^t \int_0^\infty \frac{e^{-as}}{s^{1-t}}\ ds$$  So integral we want to calculate is $$ \lim_{t\rightarrow 0}\ [a^{-t} - b^{-t}]\ \Gamma(t) $$ Right ?  See I found the following article


Why the string match condition always gives false?

I am newbie in Java. Was looking at the below condition. The Type always return String but the condition always returns false. If I do direct "Test" == "Test" then it matches. And output for both the words are Test. Can some one please let me know why it is false? Thanks.  public static void main(String []args){          String word = "Test";          System.out.println((word.substring(0,1).toUpperCase() + word.substring(1)).getClass().getName());     System.out.println(word.substring(0,1).toUpperCase() + word.substring(1));     System.out.println(word.getClass().getName());     System.out.println(word);     if(word.substring(0,1).toUpperCase() + word.substring(1) == word)     {         System.out.println("t");     }     else     {         System.out.println("f");     }       }


I lost my iPhone after I checked it in find my phone it shows that the device is offline.   I want to know it means that the phone is 100% switched off or find my iPhone was not kept on in my iPhone [because I don't remeber correctly it was on or not]   Does find my iPhone works on International Mobile Equipment identity number or Subscriber Identity Module?


python error with gloal and local variable declaration, changing variables value after beeing declared

So I keep getting the error: UnboundLocalError: local variable 'old_result' referenced before assignment and I dont exactly know why. I usually code in javascript, so im new to python but as much as ive figured its because i declare old_result in the function again, but I would like to make it global and just change its value in the function. Anyway I can fix this?  from PIL import Image, ImageGrab import pytesseract import threading import winsound   old_result = 100  def ocrit():     threading.Timer(5.0, ocrit).start()     img = ImageGrab.grab(bbox=(110,70,250,200))     result = pytesseract.image_to_string(img,      lang='eng')     print(result)     new_result = int(result)      if new_result < old_result:         print("play da music")         old_result = new_result   ocrit()


The human body is amazing. But there seems to be some evolutionary changes that appear to not make sense regarding redundancy.   While not necessarily the primary reason for their existence, the human body has a great deal of redundancy.    Two eyes.  Two arms. Two legs Two ears Two nostrils Two lungs Two kidneys Two sets of teeth A very large liver that can work in part. Two brain hemispheres that can (to some degree) do the work of the other. An appendix that is not critical.   But why do we not have two hearts? It would seem like a good idea to have two smaller hearts, together they work above optimally, but survival would be possible with one.


Why does Twitter Bootstrap add ::before and ::after?

I've noticed that when I inspect code made with bootstrap classes, there tends to be lots of ::after and ::before properties in the CSS. An example is below (from w3schools site).  Could someone please explain in broad terms what these extra properties are designed to achieve, and why they seem to appear on almost all elements?   From what I can tell, they are making all excluded elements into table elements and adding an empty space of text. I assume this if for layout purposes, but I'd love to learn more about the reasons it's done.    <!DOCTYPE html>     <title>Bootstrap Example</title>   <meta charset="utf-8">   <meta name="viewport" content="width=device-width, initial-scale=1">   <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">

Grid

This example demonstrates a 50%/50% split on small, medium and large devices. On extra small devices, it will stack (100% width).

Resize the browser window to see the effect.

       Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
       Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

       Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam, eaque ipsa quae ab illo inventore veritatis et quasi architecto.


Is there a difference between a spigot and a faucet (usage in AmE)

What is a domestic tap called commonly in the US ?  -a spigot?   a device that controls the flow of liquid from a large container (MW)   Dictionary meaning aside, I had this understanding that a domestic tap is known as a faucet.


If to love or like something is *phile, and to fear something is *phobia, then what is to hate something?


Opacity problem over white object in Illustrator

I have a problem. I'm working with an object at 50% opacity. When it's over the artboard itself the color looks great, but when I put a white object behind it I get this weird color that doesn't look accurate.  This happens with every object and only in CMYK. I'm pretty sure this never happened to me before so maybe I changed something in the settings or I don't know.  Does anyone have any idea?


Javascript: Changing elements of shallow copy array affects original

can someone explain the reason for the behavior below?  In scenario 1 if I alter an element of the shallow copy of the array, the original array is affected.  In scenario 2 if I alter the shallow copy of the array directly by just assigning an empty array to it, it doesn't affect the original array.  What am I missing here? All I want is scenario1  to NOT alter the original array. Cant' really find an answer on this...      //scenario 1 var peopleOriginal =[   {name: 'alex', age:999 } ] var peopleCopy = peopleOriginal.slice() var updatedPerson = peopleCopy[0]; updatedPerson.name = 'bob';  console.log(peopleOriginal) // {name: 'bob', age:999 }  // scenario 2 var peopleOriginal2 =[   {name: 'alex', age:999 } ] var peopleCopy2 = peopleOriginal2.slice() peopleCopy2 = []  console.log(peopleOriginal2) // {name: 'alex', age:999 }


I have a problem with a virus in windows 7, I don't know what kind of virus is infected my OS, I installed kasersky antivirus, and clear all detected viruses. After that I can't open any antivirus sites, can't ping any antivirus sites. example:  C:\Windows\system32>ping kaspersky.com Pinging kaspersky.com [38.117.98.231] with 32 bytes of data: General failure. General failure. General failure. General failure.  Ping statistics for 38.117.98.231:     Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),   When I ping to other sites, I get reply normally: example woth pinging to google.com  C:\Windows\system32>ping google.com  Pinging google.com [31.7.160.224] with 32 bytes of data: Reply from 31.7.160.224: bytes=32 time=2ms TTL=61 Reply from 31.7.160.224: bytes=32 time=2ms TTL=61 Reply from 31.7.160.224: bytes=32 time=1ms TTL=61 Reply from 31.7.160.224: bytes=32 time=1ms TTL=61  Ping statistics for 31.7.160.224:     Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), Approximate round trip times in milli-seconds:     Minimum = 1ms, Maximum = 2ms, Average = 1ms   I tryed any antispyware/antimalware softwares, but null results.  Anyone else encountered this problem?


I've seen the expression in some company names; for example , .  Is the expression "All things X" a parody of some other popular phrase, or does it have its own meaning? Or is it just a misuse of grammar?


getopts: How to accept arguments that aren't tied to an option in my script?

I'm writing a Bash script that has the following usage:  ci-badge -t|-a [-b branch] [-m] [-d description] [-l [link] ] repo   Examples:  $ ci-badge -t foo/bar $ ci-badge -ab dev foo/bar -m $ ci-badge quux/bar -md 'Hello, world.'   More samples can be found  on GitHub. Anyway, I'm wondering exactly how to implement argument parsing for this script using getopts. After a few hours looking at  basic getopts guide and scouring SO, this is what my code looks so far:  #!/usr/bin/env bash  generate_url=false # set to true if -l is passed with no arg markdown=false # true -> surround the URL with markdown  # Parse options while getopts ':tab:md:l:' opt do     case "$opt" in         a) service=appveyor ;;         b) branch=$OPTARG ;;         d) description=$OPTARG ;;         l) url=$OPTARG ;;         m) markdown=true ;;         t) service=travis ;;         # Colon: runs if no args are passed to         # an option that normally requires parameters.         :) test "$OPTARG" = l && generate_url=true ;;         # ?: Runs if an invalid option is passed.         '?') die ;;     esac done   As you can see, most of the functionality is there, but I'm wondering how to accept repo as an argument to the script. Since getopts stops parsing after it encounters the first non-option argument, I'm wondering, how would I implement this (preferably with minimal complexity)? The  I linked earlier doesn't seem to mention dealing with arguments that aren't associated with an option, so I'm a bit lost.  Thanks for helping!


I believe that the following statement is true, but I couldn't prove it.  Let $u,m,k\in \Bbb Z$. If $\gcd(u,m)=1$ then there exists an integer $k_1\in\Bbb Z$ such that $\gcd(mk_1+u,mk)=1$ Thanks.


document.createElement('p').setAttribute('onclick', 'view()') not working

I am having a slight problem with the .setAttribute command. I am creating an element called view:  var view = document.createElement('p') view.innerHTML = "VIEW" view.style.color = "#e60f0f" view.style.fontFamily = "Montserrat" view.style.fontWeight = "600" view.style.fontSize = "13px" view.style.right = "5px" view.style.position = "absolute" view.style.top = "0px" view.style.marginTop = "5px" view.style.backgroundColor = "transparent" view.style.padding = "10px" view.style.borderRadius = "7px" view.setAttribute('onclick', 'view(name, date, type)') document.getElementById(newId).appendChild(view)   When I run this, everything renders except the .setAttribute() function. I don't have the sligthest idea why. Does anyone know? Thank you SO much!  Here's the view() function in case you need it:  function view(name, date, type) {   window.location = '/flightStatus?name=' + name + '&date=' + date + '&type=' + type }   Just as another note: I am sending this to Node.js... I don't think that matters, the code above is client-side :)


Does this normal distribution plot show a good fit?

I am not well acquainted enough to judge this well. This plot was obtained from normplot in Matlab. There is a good linear fit although the tails are concerning. Does my data follow a normal distribution, judging from this?


Highlight whole TreeViewItem line in WPF

If I set TreeViewItem Background it highlights the header only. How can I highlight the whole line?   I have found a post almost solving a problem   But there are some problems: 1. It does not highlight the whole line 2. The tree has XP style on Vista. I whould like it to looks the same way on Vista as it was, but if user changed the theme to XP - it should be XP way. 3. So many XAML...  Any ideas, what I should look for?


How to download a file using Selenium's WebDriver?

Basically I want to at least check that a download-able file exists / download link works and preferably get stuff like the file size too. Here's an example: link = self.browser.find_element_by_link_text('link text') href = link.get_attribute('href') download = self.browser.get(href) print download  That fourth line prints "None", presumably because I haven't manually clicked the Save button, and even if I had, I doubt WebDriver would be able to "see" the file. Any ideas? I'm using Firefox as my browser-under-test, and I understand that the file handling for downloads is somewhat browser and/or OS-specific.


How to revert a GitHub repo to a certain commit

I've been committing changes inside my GitHub repo. I now want to roll back to a certain commit that I've made sometime ago.  How do I reset my repo so that all the commits I've made, after the one i'd like to go back to, are wiped?  I've found some answers regarding git reset --hard <id> but it's not doing what I want.


How does for(i=0; i<5; x=(i++,a++)) work

I can't understand how this works and why it produces  the following output.  int main() {     int i=0;     int a=5;     int x=0;      for(i=0; i<5; x=(i++,a++))     {         printf("i=%d a=%d x=%d\n",i,a,x);     } }   this give as output:  i=0 a=5 x=0 i=1 a=6 x=5 i=2 a=7 x=6 i=3 a=8 x=7 i=4 a=9 x=8


How can I add non-free network firmware to my Devuan install?

I have a Dell PowerEdge T710 I'm trying to run as a home server. I have successfully installed Devuan, however I failed to set up the network properly. I'm wondering if there's any way to add the non-free network drivers for its Broadcom Limited NetXtreme II BCM5709 Gigabit Ethernet controller. I'm also open to reinstalling, but if I'm gonna do that I'd like some guidance on adding the proper network firmware to the installation image. I'm also open to giving up and using the debian non free net install iso. (I'm using Devuan to play with other init systems eventually but its not super important that I stay with this distribution)


Converting csv to kml/geojson using ogr2ogr or equivalent command line tools?

I've just unsuccessfully tried to use ogr2ogr to convert CSV into KML like so:  ogr2ogr -f "KML" output.kml input.csv   The csv has "latitude" and "longitude" columns.  The attributes are all loaded but if you inspect the KML's text, the Coordinate elements are not being added so its not working.  I feel like this will work if I can inform gdal to interpret certain columns ("latitude", "longitude") as coordinates.   How might I do this?


Why continuum function isn't strictly increasing?

Is there any example that for cardinal numbers $\kappa < \lambda$, we have $2^\kappa = 2^\lambda$?  My guess is that it only depends on whether GCH holds. Is it true?


How could the series below be computed ? $$\sum_{k=0}^{\infty}\frac{1}{2^{k!}}$$ It's not a series from a book, but a series I thought of many times, and I didn't manage to figure out what I should do here. I'm just curious to know if there are some known ways for approaching such a series. Thanks!


Kids movie. Two friends set their wrist watches / alarms to remember to watch a TV show. One goes into the past and uses his watch battery to get help

I been trying to find the title of the movie involving these 2 scenes and the best description from what I can remember. I can’t  think who the 2 kids I think both are male and have a watch alarm set to watch a specific tv show. But I am thinking pretty sure came out in the 90s and had to do with time travel somehow to the past. Only one of the friends goes back not sure how.  So I only remember parts involving a wrist watch. First in the beginning two friends both have a wrist watch alarm set to remind them both to watch the same TV show. Then when one of the friends that goes into the past, his alarm goes off on his watch to remind him to watch the TV show but somehow helps by getting an idea using the watch battery.  The watch didn’t cause the time traveling only that the battery of the watch was used in the past after traveling there.  Both friends that had a alarm that set for both friends to watch a specific tv show  But can’t find those scenes when I think I am close to finding the movie the scenes aren’t there and I kept thinking it’s A Kid in King Arthur’s Court but something like that kind of movie feel.  Yea kind of but it has more a 90s feel. It’s not clockstoppers is slowing down time.


Prove that $\sup \{-x \mid x \in A\} = -\inf\{x\mid x \in A\}$

I need to prove that $\sup \{-x \mid x \in A\} = -\inf\{x \mid x \in A\}$ and am having trouble moving the $-x$ out of the $\sup$ to $\inf$. Another thing is that I don't quite know how to prove $b = \inf$ (see below). Any help would be appreciated! Here my attempt:  Let $a = \sup\{-x \mid x \in A\}$  Then by definition $a \geq -x$ for $x \in A \implies -a\leq x$ for $x \in A$  Thus $-a$ is a lower bound of $A$. Assume $b$ is a lower bound of $A$  Then $b \leq -a \implies  a \geq -b$ and $a = \sup \{−x \mid x\in A\} = -\inf(A)$


I have a list of departments. This list will change over time adding new departments and "deactivating" others (because of structural changes).  I would like to use this list as a look-up for other lists, but I would only want to look-up the active departments (can be detected by a bit field "Deactivated") which should be false, when the department is active.  I'm sure this can be done, but how?


How should I use a possessive apostrophe when a name is between commas?

Is this the correct use of an apostrophe when showing a name and relationship?     When was your father, Robert's, wedding?   Thanks!


I usually catch up with whatever I last did on the Stack Exchange sites, by visiting . However, over the last week or two, that page is often blank, even though the tabs other than "all" ("accepts", "posts", "comments", etc.) are not.  Here's a screenshot:    The corresponding activity pages on individual Stack Exchange sites (Stack Overflow, Math.SE, etc.) are fine.


Save list as template using client object model in SharePoint Online

Is it possible to save list as a template using CSOM?  We need to create a list template every weekend in SharePoint Online. I thought of using task scheduler with a console application but could not find a way to save a list as a template.   For full trust code we have saveListAsTemplate method, but I couldn't find any in CSOM.  What are my options?


Can something be more unique than something else? Can something be very unique?

Family debate - one says that uniqueness is relative, others say something either is or is not unique. Does uniqueness mean that there is only one of a certain thing/person, so that it would mean more unusual than rare?


My Stack Overflow's login email is an email address that no longer exists. While I have changed the email address in my profile, is it possible to change the login email to the new email in my profile?  edit of an edit - I've only now just realised stack exchange logins are openID's and explanation of this rather than just slapping duplicate on it without saying anything might have been clearer...


Short story about a science fiction author whose books were being stolen by a time traveler

In 1988 I read a short story about a science fiction author who wrote a new novel and turned it in to his publisher. His publisher turned it down, saying they could not print plagiarized books. The author is confused, knowing it took him a long time to write it. The publisher tells him this book was written a long time ago by another author, and he goes and checks it out, finding to his astonishment that his book, word for word, already exists.  He starts work on another book and when it is finished, his publisher turns it down, too, telling him to stop passing off another guy's work as his own. They give him the title of the "original" novel and he looks it up to find that this book, too, exists word for word.  Since he is a sci fi author, it occurs to him that a time traveler may be stealing his work, so he writes a new book and pretends to go to sleep, catching a guy who sneaks into his house at night to steal the manuscript.  Turns out, the guy is a time traveler who is going to the future, stealing his books, returning to the past and publishing the manuscripts as his own.  We had to read this in high school for science fiction class and take a test on it, but I haven't been able to remember the title or author.


Why is this question a test in "reopen votes"

So here we have following question:    Which has: - no edit visible in review - no comments indicating that there is any discussion about question value  I understand that it may have been closed for wrong reasons, but that doesn't mean it is suitable for review test!  Yes, it's detailed, yes it's long, but hey - someone voted to close it in the first place? As a reviewer I see no reason why question which was once closed should be reopened just because (and why someone made a test out of it)


Can True Polymorph be used to create magic items?

The True Polymorph spell allows you to turn a creature into an object and if you concentrate on it for 1 hour it becomes permanent. The relevant text follows:     Choose one creature or non-magical object that you can see within   range. You transform [...] the   creature into an object [...].      [...]      Creature into Object. If you turn a creature into an object, it   transforms along with whatever it is wearing and carrying into that   form. The creature's statistics become those of the object...   Can polymorph be used to create magic items by polymorphing creatures into objects? Answers can have DM Fiat, but I would prefer a rules based answer or an answer by Jeremy Crawford or Sage Advice or some other 'official' source.


How can I intentionally include lens flare in my photographs?

I usually try to avoid lens flare, usually by avoiding shooting directly into bright lights (or using  to minimize it). However, sometimes I find a situation where lens flare actually adds to the image.  What can I do to effectively incorporate lens flare into my image? Also, are there any ways to do so while minimizing loss of contrast?


Proper way to manage test/prod connection strings in .NET web.config file

I have the source code of an application that I maintain. In my web.config file, I have connection strings for both my test and production databases as follows:  <add name="conn" connectionString="Data Source=TestDBServer; (etc...)">  <add name="conn" connectionString="Data Source=ProdDBServer; (etc...)">   Whenever I am in test, I just comment out the production connection string and vice-versa. For example, when I finish testing, I comment out the test connection string and uncomment the production connection string and then deploy.  I am very early on in my career as a developer, but it seems to me that there must be a better or more standard way to handle this. What should I do?  Edit  Guilherme Lofrano Corneto linked an identical question that completely answers my own question. I have since marked mine as a duplicate. Here is the link:


Templated class parameters to outside function

Is it possible to pass the template-parameters to a function somewhere else defined? For instance I have the class  Barrier.pp  template<Location L, Knock K> class Barrier {   //...   void checkBarrier( ... )   {     BarrierBest_checkBarrier<L, K>( ... );   }   //... }   Other.cpp  template<Location L, Knock K> BarrierBest_checkBarrier( ... ) {   //Use L and K to do call other function }   As I have it right now the compiler throws a unresolved external symbol for all the possible combinations of the template parameters, that is, BarrierBest_checkBarrier<1,1>, BarrierBest_checkBarrier<1,0>, BarrierBest_checkBarrier<0,1>, BarrierBest_checkBarrier<0,0>  Is there a way to make this work?


I have Long value 1282680754000 where if I check this value in  it gives me Tuesday, August 24, 2010 8:12:34 PM   But if I use new DateTime(1282680754000).toDate() I get Wed Aug 25 01:42:34 IST 2010 (It is adding +5.30 hour)  How to get Tuesday, August 24, 2010 8:12:34 PM  for 1282680754000 in java


How to move a specific trunk revision and its subsequent edits to a branch?

We realized that we would like some work in the trunk to have actually have been in a branch.  We would like several commits to go into a branch, and preferably, we would preserve the history of the commits.  So:   r0 --- r1 --- r2 --- r3   would become             branch --- r2 --- r3          / r0 --- r1 ----- *   Where "*" is where we will start making new commits to the trunk.  I'm nervous that I'll destroy our repository if I do something incorrectly.  Please advise, thank you!


Proof of inequality $2(\sqrt{n+1}-\sqrt{n}) < \frac{1}{\sqrt{n}} < 2(\sqrt{n} - \sqrt{n-1})$ using induction

Prove that $2(\sqrt{n+1}-\sqrt{n}) < \frac{1}{\sqrt{n}} < 2(\sqrt{n} - \sqrt{n-1})$ if $n \ge 1$ using induction.  Can someone help me with this problem please. Base case is easily shown, and for the inductive step I know I have to use the inequality for $n\gt1$ to show that it is true for $n+1$, but I am not quite sure how to.   Thanks.


I want to print a list, perform some operations and print again, flushing the list.  a=[1,2,3,4,5,6,7,8,9]  for i in range (0, 10):     a.append(i)     a=a[-5:]     print(*a, sep='\n')   I expect the list to be cleared from the screen and the new one takes its place, buy I don't know how to to that.


i am developing a code in which a have to read the data form list box and upload an external file, press a button named Start and with this listbox i am getting an error as shown below.     An unhandled exception of type 'System.InvalidOperationException'   occurred in System.Windows.Forms.dll      Additional information: Cross-thread operation not valid: Control   'listBox1' accessed from a thread other than the thread it was created   on.   my code is as follows  private void Start_Click(object sender, EventArgs e) {  Thread ss = new Thread(Automode);    ss.Start();  }    private void Automode()     {         ....        for (int i = 0; i < listBox1.Items.Count; i++)         {             listBox1.SetSelected(i, true);              string pattern = "[gxyzbcmij][-+]?[0-9]*\\.?[0-9]*";             string text = listBox1.Text;             Regex gcode = new Regex(pattern, RegexOptions.IgnoreCase);             MatchCollection code = gcode.Matches(text);         }         .....         }   here at listbox.SetSelected command it is giving an exception as shown above. please suggest the alternate ways to write it.


Proof that the real numbers are countable: Help with why this is wrong

I was just thinking about this recently, and I thought of a possible bijection between the natural numbers and the real numbers.  First, take the numbers between zero and one, exclusive.  The following sequence of real numbers is suggested so that we have bijection.    0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 0.01, 0.02, ... , 0.09, 0.10, 0.11, ... , 0.99, 0.001, 0.002, ... , 0.999, 0.0001, etc.  Obviously, this includes repeats, but this set is countable.  Therefore, the set of all numbers between zero and one is a subset of the above countable set, and is thus countable.  Then we simply extend this to all real numbers and all the whole numbers themselves, and since the real numbers, as demonstrated above, between any two whole numbers is countable, the real numbers are the union of countably many countable sets, and thus the real numbers are countable.    Please help me with this.  I understand the diagonalization argument by Cantor, but I am curious specifically about this proof which I thought of and its strengths and flaws.  Thanks.


whether the recently published Bash/Apache problem posed a threat to operations.  In my Ubundu verion is Ubuntu 10.04.3 LTS if i need anything applying patches.  Regards, Ashok


Converting NSString into asterix(*) format depending on the Length in iOS

I want to convert the NSString into asterix (*) format depending on the length,So how to do it..  if([str1 lenght]) {     str2 = "*"; }   Regards Ranjit


How to create a circle with the Array Modifier

I was trying to create the same as in this tutorial:    But when I do exact the same my objects keep regrowing. So each next object will be even bigger then the one before.  Can someone please tell me what I did wrong here?


How do I access the files in a Samsung Galaxy S II?

I have a Samsung Galaxy S II but my Ubuntu 10.04 laptop, although it recognizes the phone when I connect it with a USB. won't allow me to get into the phone. Do I need special drivers?


Simple script to batch-convert KML to SHP or G

I'm not sure if this is possible given the looseness of KML files, but I have a couple thousand KML files that I would like to convert to SHP files. They are almost exclusively line or point data. I believe it is mostly possible to convert kmls via a GUI functionality in QGIS or ArcGIS but I would hopefully be able to do them all at once via command line.


On my Mac (still running Mojave), I typed by mistake (because caps lock was on) CD  into my Z-shell. Not surprisingly, I did not get to my home directory. However, there was no error message either, so I started to investigate. Here the transscript of my session: % type CD CD is /usr/bin/CD % ls /usr/bin/C* /usr/bin/CpMac % ls -l /usr/bin/CD* zsh: no matches found: /usr/bin/CD* % stat /usr/bin/CD 16777220 12885606796 -rwxr-xr-x 15 root wheel 0 190 "Feb 23 04:02:09 2019" "Feb 23 04:02:09 2019" "Aug 15 19:49:23 2019" "Feb 23 04:02:09 2019" 4096 0 0x80020 /usr/bin/CD % ls /usr/bin|grep -i CD cd ncdestroy % stat /usr/bin/cd  16777220 12885606796 -rwxr-xr-x 15 root wheel 0 190 "Feb 23 04:02:09 2019" "Feb 23 04:02:09 2019" "Aug 15 19:49:23 2019" "Feb 23 04:02:09 2019" 4096 0 0x80020 /usr/bin/cd  So, there is no file named CD in /usr/bin, but an executable file named cd, and zsh decided in an unappreciated attempt of kindness to use the latter. I am aware that zsh is searching for executables case-insensitively. This still leaves the question: What is the purpose of this file /usr/bin/cd? It can't be for changing the working directory, as this can't be done using an executable. What else is it for?


Proof that two spaces that are homotopic have the same de Rham cohomology

I know this is true, but how do I prove it? Specifically, I'm trying to calculate the de Rham cohomology of the 3-sphere by using the Mayer-Vietoris sequence and covering $S^3$ with two hemispherical sets $U, V$, such that $U$ intersects $V$ in a "2-band", an equatorial band homotopic to a 2-sphere.


Real Analysis, Existence of a Limit Boundedly:$|\int_0^b\frac{sin(ax)}{x}dx | \le c$

I need to show that there exists a $c$ such that $|\int_0^b\frac{sin(ax)}{x}dx | \le c$, where $a$ is any real number, and $b$ is any real number greater than 0. Also I need to show that the smallest $c$ possible is $c=\int_0^\pi\frac{sinx}{x}dx$. I know that $\int_0^\infty \frac{sin(ax)}{x}dx = sig(a)\frac{\pi}{2}$ where $sig(a)$ literally just means positive one or negative one, depending on the sign of $a$. I think the fourier tranform of the characteristic function on the interval $(0,a)$ is $\frac{sin(ax)}{x}$. After that, I am unsure about how to proceed. Thanks for your help!


Account said to be suspended network-wide, but it's not

There is a user account that has a suspension message on Mi Yodeya that says they are suspended network-wide until 2025. However, they have several other accounts, and none of them appear to be suspended. The user voted to close a question on Mathematics today, so they are clearly not suspended. Is this suspension message specific to the site? Did the moderators for the site erroneously choose this message, or does it not mean what I think it means? The other possibility is that it is a bug and that they are supposed to be suspended network-wide, but are not. This may not be a duplicate of , since the user is suspended "network-wide" on just one site, not all sites but a few. In that case, the user in question had been manually unsuspended on just one site by a moderator there. While it might be possible that local moderators unsuspended the user on all of their other sites but one, this may not be the case here.


How can i format a SD card that can't be read unless it's locked?

I have a relatively new SD card that was in use for about a year in my camera, then suddenly the camera complained that it couldn't write to it anymore.  When I put it in my PC it shows up as a drive, but cannot be opened as the explorer process hangs until I either kill it or remove the card. I can't even right-click it to get to the format menu as the process will hang there as well. Diskpart won't start either with the card in.  The card was not locked, however when I locked it it was immediately recognized and I could view the pictures still on it. Removed, unlocked, inserted again and the explorer hangs.  I downloaded  after reading about it, but apparently it doesn't work on Windows 10 – when I launch it the process runs but no window appears (tried admin & compatibility mode, no success).  Any ideas what's going on? I'd like to try and format it to see if that solves anything, but I'm out of ideas on how I'll get that done.    Update about the card being readonly or write protected: is a card that crashes the explorer read-only? Cause that is the problem. I cannot use the card at all unless I lock it with the hardware switch, only then can I read the files on it. If that is the expected behavior of a read-only card, please write an answer and I'll accept it. I don't believe that's the case though.


How To Fill The Hollow Parts With Another Material?

I making a simple mesh of two different materials as shown in the figure, the question is how can I differentiate both of them in Blender?


I'm a student majoring in mathematics. I've taken a course in mathematical logic and a course in set theory. My problem is basically that I'm always finding philosophical concepts, for example syntax, semantics, epistemology, denotation, intuitionism, constructivism, idealism, etc., and when I look up their meaning on Wikipedia there are still more and more new concepts. So I wonder that maybe instead I should start studying philosophy in a consistent and organized way instead of learning isolated concepts, but I don't know how to do that.   To be more precise, in mathematics and in every other science mostly the basic concepts are given at the beginning and then everything goes from there. This we can call it "the foundations". For example, in mathematics we can start with logic and set theory. From them every other branch is derived: geometry, analysis, algebra,..., all of mathematics. This makes its study very pleasant and organized. My question is then if there's something similar to study philosophy. Where do I start? Is there an organized way to study philosophy?


What is correct: "I don't wake up as soon as him" or "as soon as he"?

I guess "he", because I can say "as soon as he does", but I feel like "him" should be correct as well.


creating a scene in the beginning was easy because i could zoom in all i wanted in order to do model the mesh, but after i place more objects i reach a point where it is hard to move around in the model space because it would slow down to a stop, also i cant just rotate my view and zoom into an object. I was wondering if i can change this. I've seen that by pressing "." i can zoom into the mesh, yet i would like to know if theirs another way so that i wouldn't  have to do this every time. I've also tried changing the navigation auto depth on and off in preferences. (currently using Blender 2.8)


How to incorporate counter in list label

I want to label my enumeration like SOMETEXT01, SOMETEXT02, ..., SOMETEXT10, etc. I read through a couple of questions and know how to create a counter that adds in leading zeros.  \newcounter{counter} \newcommand*{\getCount}{%   \ifnum\value{counter}<10 0\fi%   \arabic{counter}% } \getCount \setcounter{counter}{10} \getCount   How can I use it with the labeling?  \documentclass[12pt]{article}  \usepackage[T1]{fontenc} \usepackage[latin1]{inputenc} \usepackage{enumitem} \usepackage{ae} \usepackage[pdftex]{graphicx} \usepackage{vmargin} \usepackage{url} \usepackage[absolute,overlay]{textpos} \usepackage[german]{babel}  \newlist{frequirements}{enumerate}{3} \setlist[frequirements, 1]{labelindent=0pt, label*=\textbf{/FR{\arabic*}/},itemindent=0em,leftmargin=*}   \begin{frequirements}     \item \textbf{Do this} \\ You should always be able to do this.     \item \textbf{Validate} \\     After doing this, the user should be able to validate. \end{frequirements}  \end{document}     Output looks like  /FR1/ Do this  You should always be able to do this.  /FR2/ Validate  After doing this, the user should be able to validate.


Prove that 2 numbers a and b are divisors of lcm(a;b)

I got asked to prove this which makes no sense to me “Proof if a and b are two arbitrary numbers then (a,b) are divisors of lcm(a;b)” Isn’t this a part of the definition of lcm? What is there to prove?


Is it possible to get back your deleted Terraria character?

My brother accidentally deleted his character. Is he able to get back his stuff by backing up his whole iPod?


Will using page headings (h1, h2, h3 etc) as internal links encourage Google sitelinks?

I am trying to change my site's page headings to better emphasize the structure of the page's content hierarchy. I am hoping this will encourage Google Sitelinks and list snippets.   Current headings are not optimized: I would like to use the
 heading as an internal link.  Will this encourage Google sitelinks and better content indexing?
text


So this year I'm finishing my masters degree in Security of Information Systems, in a third world country University (best in my country but still) , and I might have a chance at a fully funded scholarship in a way better university abroad, I was thinking of getting a second masters degree in robotics, Artificial intelligence or Cognitive systems.  Is it worth it ? with a bachelor degree in Computer science and a masters in SIS do I fulfil the requirements ?   There is also the matter that I'm going to be fully relying on the scholarship's funding, and of course I still can try to apply for a Ph.D scholarship abroad, but I heard it's more difficult to get it.  Getting a PhD in my country would be fairly easy, but that's not something I'm really interested in for several reasons, First the pace and level of research over here is not really that good. Second, I'm thinking an experience abroad might really help me at many levels. And here comes the point I'm not really sure about, does having 2 masters degrees give me a chance at a better job ? or a better chance at getting accepted for a PhD ?   PS : The graduation project I'm working on right now is a mix of Forensics, Security, massive parallel computing and artificial intelligence.   Thank you  EDIT :  Okay, I am to rephrase my question, I'm a passionate learner, I want to have the experience of studying abroad, I enjoy many fields in computer science, my question is, can this actually hurt my career ? personally I don't mind "postponing" its start, as long as it's harmless and I'm doing something I enjoy.


Proving certain polynomials are irreducible over $\mathbb{Z}$

Show that the polynomial $(x-1)(x-2)...(x-n)-1$ is irreducible over $\mathbb{Z}$. [hint: if the polynomial factors consider the values of the factors at $x = 1,2,3....,n$.  Show that the polynomial $(x-1)(x-2)...(x-n)+1$ is irreducible over $\mathbb{Z}$ $\forall n \geq 1, n \neq 4$.  I've been running around in circles on this one for awhile now and can't seem to get anywhere! Some insights would be greatly appreciated! Thanks yall!


Homeomorphism between $[0,\infty)^n$ with Upper Half-Space $\mathbb{H}^n$

I've been working through an exercise in Lee's Smooth Manifold. The author ask us to show that the space $\bar{\mathbb{R}}_+^n := [0,\infty)^n$ is homeomorphic to upper half-space $\mathbb{H}^n := \mathbb{R}^{n-1}\times[0,\infty)$, both equiped with the usual topology.  I managed to construct a homeomorphism $f : \bar{\mathbb{R}}_+^2 \to \mathbb{H}^2$ defined by restriction of the map $f(z) = z \, e^{i\theta} = r \, e^{i2\theta}$ to $\bar{\mathbb{R}}_+^2=[0,\infty) \times [0,\infty) \subset \mathbb{R}^2 \approx \mathbb{C}$. Alternatively, a more pleasing  the map like $f(z) = z^2$. So we have $$ \mathbb{H}^2\approx \bar{\mathbb{R}}^2_+.  $$ To proceed i tried for $n=3$ case but it's messy. After a while i came up with this induction: Suppose that $\mathbb{H}^n\approx \bar{\mathbb{R}}^n_+$ for all dimension less than or equal to $n$. Clearly this hold for $n=1$. By definition of upper half-space, \begin{align} \bar{\mathbb{R}}^{n+1}_+ = \bar{\mathbb{R}}^{n}_+ \times \bar{\mathbb{R}}_+ &\approx \mathbb{H}^n \times \bar{\mathbb{R}}_+ = \mathbb{R}^{n-1} \times \bar{\mathbb{R}}_+ \times \bar{\mathbb{R}}_+  \\ &\approx \mathbb{R}^{n-1} \times \mathbb{H}^2 = \mathbb{R}^{n-1} \times \mathbb{R} \times  \bar{\mathbb{R}}_+ = \mathbb{R}^n \times \bar{\mathbb{R}}_+ = \mathbb{H}^{n+1}. \end{align} In the argument above i use the following result : if $A \approx B$ then $A \times C \approx B \times C$, which i think can be done by set $f : A \times C \to B \times C$ to be $f(a,c) = (\varphi(a),c)$, where $\varphi$ is a homeomorphism between $A$ and $B$.     Is this proof correct ? Is there any other (correct) proof for this ? I tried to googling it but i found nothing. If possible, can anyone give me references for manifold with corner ? Thank you.


Passing an array by reference in JavaScript and overriding array

In the line I have commented below, does the value of the array that has "element" as a value get overridden by array?   let c = [1, 2]; console.log(`c = ${c}`); add(c, 3); console.log(`c = ${c}`);  function add(array, element) {   array = [element]; // Is this Array that has "element" as a value overridden by array }


complex numbers- how do I prove the following statement?


Check if overflow:hidden div is overflowing jQuery

I just would like to know if there is a way to check if a div with the overflow hidden attribute can be checked to see if it has content overflowing it or not. Jquery


Proving that a sequence converges (boundedness)

I know that this is a cauchy sequence. But I am interested in what I wrote in line 8 to 12. I was wondering if it was correct at all? I am trying to learn the bounded sequences proof We assume that the terms of a sequence ${S_n}$ satisfy this property $\forall n$ $$|a_{n+1}-a_n| \leq \Big| \frac{1}{2^n} \Big| $$ Now I would like to show that $\{a_n\}$ converges. Specifically towards $0$ As $ \ n \longrightarrow \infty \ \text{,  we have }  \dfrac{1}{2^n} \longrightarrow 0$ Also $|a_{n+1}-a_n| \geq 0$ So we have, as $ \  n \longrightarrow \infty$ $$\text{(line 8) }\hspace{1cm} 0 \leq |a_{n+1}-a_n|  \leq 0$$ $$\implies \hspace{1.2cm} \ 0 \leq |a_n - a_{n+1}|  \leq 0$$ by triangle ineq. $$\implies \hspace{1.2cm} 0 \leq |a_n| - |a_{n+1}|  \leq 0 $$ $$\text{(line 12) } \implies \hspace{0.2cm} \ 0 \hspace{.2cm} \leq \hspace{.2cm}|a_n| \hspace{.2cm} \leq \hspace{.2cm}0$$ Can I use this to say that this sequence is bounded and thus converge to $0$ Note: To be honest, I feel this is correct but I am not satisfied with the argument.


least square estimator of regression x onto y

I've been reading linear regression and least square estimator. Suppose we have i.i.d data $(x_1, y_q), (x_2, y_2), ..., (x_n,y_n)$ such that we use a linear regression model $y_i = \beta x_i + \epsilon_i$ and learnt the fact that we often derive least square estimator $\hat{\beta} = \frac{\sum_{i = 1}^{n}x_iy_i}{\sum_{i = 1}^{n}x_i^2}$. However I wonder what would be the effect if we do regression of x onto y. Would we then be able to use the least square estimate for the regression of x onto y to estimate of $\frac{1}{\beta}$? How do we decide whether this is a good estimate in the first place?


Java data structure that order objects according the occurance

Is there a data structure such that I can input all the objects to it and then it will return the objects according to the number of occurrence (e.g. in descending order). All I can think of is using a hash map. The key of the hash map is the object and the value is the occurrence of the object. Every time I input an object, I increment the value of the corresponding key. However, in this way, if I want to output the objects according to the descending order of the occurrence, I need to traverse the hash map once. Is there a more efficient way to implement this in Java?


using ID selector for to addMethod for jQuery validate

I am trying to add a validation rule for jQuery validate  $validator.addMethod('footer-email', function (value) {   if (value == ''){     return true;   } }, '');   Where footer-email is class selector. Is there a way I can use a ID selector instead?


As per the tocloft package documentation, we should be able to use \renewcommand{\cftsecpresnum}{something} to insert some text before the section number in the table of contents (for example, should work for list of tables, list of figures, and a custom list using \newlistof).  However, when I use that command the I want to insert before the section heading entry in the table of contents overlaps with the section heading text. See MWE. Am I missing something here? I did not immediately see an answer to address this, specifically as to whether or not the \cftsecpresnum command from the tocloft works or not. As per below I would have to use \cftsecindent as a work around, but that was not mentioned in the package documentation and not sure if that is the intent.  Thanks in advance!  \documentclass{report}  \usepackage{tocloft} \renewcommand{\cftsecpresnum}{Something }  \begin{document}  \tableofcontents  \section{what}   Bananas  \section{is the deal}   Apples  \end{document}


A group is abelian if and only if the center of the group is all the group

Isn't it the same to say that a group is abelian, and that the center of the group is all the group?   I have an exercise to prove that this is true, and it's exactly one stroke for each direction of the proof, correct me if I wrong:   First direction: The group $G$ is abelian, therefore for each $a,b\in G$: $$ab\:=\:ba$$ Therefore, in other words: $$a\in G\::\:Z(G)=\{ab\:=\:ba\::\:b\in G\}$$ and by definition of center (which here I symbolized as $Z(x)$), the center here is every element of $G$, therefore it is whole $G$ itself.  Second direction:  That is true: $$a\in G\::\:Z\left(G\right)=\left\{ab\:=\:ba\::\:b\in G\right\}$$ and in other words, for each for each $a,b\in G$: $$ab\:=\:ba.$$  What should I add in this proof, does it seems that i missed something? I mean it seemed pretty trivial, both directions.


Hash Sum mismatch when trying to download package

E: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/focal-updates/main/binary-i386/by-hash/SHA256/a94eda4aa2d3ef5591bfc752e3446df9449aeaeef37cddda99c5a5089b9fb665 Hash Sum mismatch    Hashes of expected file:     - Filesize:489712 [weak]     - SHA256:a94eda4aa2d3ef5591bfc752e3446df9449aeaeef37cddda99c5a5089b9fb665     - SHA1:4783af61fdabef822421f227c2a968540608bb34 [weak]     - MD5Sum:1fe09da1647b451c6e918f78310cca31 [weak]    Hashes of received file:     - SHA256:d4811bef2509943ed331570c5039a8b652d13d67fe1561c52f0f8ebb61e4dae0     - SHA1:becffd49c534396f23867c6d7659e83784cb70a1 [weak]     - MD5Sum:2a207edc62799b702bf497cc5464177a [weak]     - Filesize:489712 [weak]    Last modification reported: Tue, 15 Jun 2021 07:37:08 +0000    Release file created at: Tue, 15 Jun 2021 09:11:40 +0000 E: Some index files failed to download. They have been ignored, or old ones used instead.


Why does `losetup` need to associate loop devices with block devices?

man losetup says     losetup is used to associate loop devices with regular files or block devices, to detach loop   devices, and to query the status of a loop device.    says      In Unix-like operating systems, a loop device, vnd (vnode disk), or lofi (loop file interface) is a pseudo-device that makes a file accessible as a block device.   Since a loop file makes a file accessible as a block device, why  does losetup need to associate loop devices with block devices? Isn't that unnecessary? Thanks.


Why POCO objects are created using classes instead of structs in C#, while POCO is intended to carry only public attributes and not any behaviors?  Do we really need to create a class with get and set accessors? I think structs would be much cleaner and simple to carry object's state.


How does the current remain the same in a circuit?

I understand when we say current, we mean charge (protons/electrons) passing past a point per second. And the charges have energy due to the e.m.f. of the power supply.  Now tell me, if a lamp has resistance and you hook it in the circuit, how will the current stay the same? The charges obviously lose energy in the lamp and so become SLOWER, which should mean current decreases, right?  [Edit] All answers explained a bit of everything, so it was hard to choose one. If YOU are looking for an answer, please check the others too, in case the accepted one doesn't answer your question.


If $M$ is finitely generated left module over a left noetherian ring $R$, then $M$ is a noetherian module.  I need to show that an arbitrary ascending chain of submodules of $M$ must satisfy ACC, or equivalently, every submodule of $M$ is finitely generated.   Since $R$ is a left noetherian ring, every left ideal in $R$ is finitely generated. I am trying to find a 1-1 correspondence between left ideals of $R$ and submodules of $M$.  Is it a correct way, or how can I show the assertion by a different way? Thanks.


Which of the following is correct ?  1)  A, B, C and D  2)  A, B, C, and D


attempt to invoke virtual method java lang String split

the code is trying to read a comma delimited text file  this is the code that is giving the error     while((PlaceHold = in.readLine())!=null){             PlaceHold = in.readLine();             String[]Split = PlaceHold.split(Delimit);             db.Restaurant1.setFoodName(Split[0]);             db.Restaurant1.setCarbs(Split[1]);             db.Restaurant1.setServingSize(Split[2]);             db.addRestaurant(new DBLocationHelp.Restaurant(Split[0], Split[1], Split[2]));         }   and this is the error it gives  java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.diabeticdiner/com.example.diabeticdiner.Arby}: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String[] java.lang.String.split(java.lang.String)' on a null object reference