In c++ why we can overload `operator ->` and can't overload `operator .`

In c++, why we can overload operator -> and can't overload operator .? Similarly, why we can overload operator ->* and can't overload operator .*? I will be appreciated if you can help me!


OK, I got it. There has been plenty of  asking dumb good practice questions. And yes, most of the good practice questions lead to opinion-based answers.  But then, good practices a essential for learning and mastering programming languages. And good practice question may even be .  StackExchange's format is great to gather opinions from experienced users. So if I still have good practice or a opinion-based questions (e.g. I hesitate between two ways of programming/structuring my code and I would like experienced users to argument over one or another), where can I ask them?  Couldn't there be a sub-site of StackExchange dedicated to such kind of questions?  I know my question is pretty opinion-oriented. But Meta is the one place where opinion-oriented questions are asked. Why not somewhere else?


No access to desktop after upgrade to 18.04 LTS

I can't access the desktop when I restart my PC after upgrading from 17.10 to 18.04 LTS. It just keeps taking me to a command terminal. I will appreciate any form of assistance and help.


Can Jon be released from his vow to the Knights Watch?

Jon Snow took the vow to join the Knight's Watch for the rest of his life...but he has died so that would release him. Since he came back to life he has not retaken the vow.


I know that this sequence converges because it is increasing and bounded (well, this is the usual way to prove it). In some books, the number $e$ is defined to be this limit.  But in other books the number $e$ is defined this way: $$e=\sum_{n=0}^\infty\frac1{n!}$$ and the exponential function $$e^x=\sum_{n=0}^\infty\frac x{n!}$$  But my problem is to prove that both definitions are consistent. Assumig the second definition of $e$ and $e^x$, I have done this:  I define $f_n(x)=\left(1+\frac xn\right)^n$. Then I take any compact interval $[a,b]$ and I show that the numeric sequence $$\left\{\left(1+\frac xn\right)^n\right\}_{n=1}^\infty$$ is monotonic and bounded for every $x\in[a,b]$. So the sequence of functions $f_n$ converges -pointwisely at least- in that interval. Let be $f$ the limit.  Now $$f'_n(x)=\frac1nn\left(1+\frac xn\right)^{n-1}$$ and we see that $\lim f'_n=f$; therefore, $f'=f$.  Since $f(0)=1$, we deduce that $f(x)=e^x$.  This is not an exercise or anything like that, but I'd like to ensure if vevery step in my proof is correct.  I am specially dubious with the derivative of the sequence. Do I need uniform convergence to do that? How could I show it in this case?


Why doesn't GRUB2 menu appear? (Windows 10 and Ubuntu 16.04 dual-boot)

I have been struggling with the following issue for a while: I have installed Ubuntu 16.04 in dual-boot with Windows 10 (x64 version) on my HP laptop equipped with a UEFI instead of a good-old BIOS, and I can't seem to access the GRUB2 menu from which I can launch either Ubuntu or Windows 10. The boot process is always hijacked by the Windows Boot Manager. I've tried many solutions after reading so many similar questions on different forums and in different tutorials. 1- I turned off Windows 10's fast-startup feature. 2- I changed the boot order using an elevated command line in Windows 10:  While keeping secure boot enabled : bcedit /set {bootmgr} path \EFI\ubuntu\shimx64.efi  While disabling secure boot from the UEFI settings : bcedit /set {bootmgr} path \EFI\ubuntu\grubx64.efi   3- I've tried accessing Ubuntu in LiveCD mode from a bootable USB and used the utility "boot-repair" to repair the boot-order and ended up with having an error:  an error occurred during the repair. Please write on a paper the following URL:  In case you still experience boot problem, indicate this URL to: boot.repair@gmail.com You can now reboot your computer. Please do not forget to make your BIOS boot on sdb (1000 GB) disk! If your computer reboots directly into Windows, try to change the boot order in your BIOS. If your BIOS does not allow to change the boot order, change the default boot entry of the Windows bootloader. For example you can boot into Windows, then type the following command in an admin command prompt: bcdedit /set {bootmgr} path \EFI\ubuntu\shimx64.efi  Thank you very much ahead for your help and effort!!


Smallest template for a LaTeX Ph.D. thesis?

I am looking for a most minimum template/example for a LaTeX Ph.D. thesis.  I am going to write a dissertation/Ph.D. thesis.  I use Ubuntu with pdflatex (minimum installation of TeX Live). The goal is to keep it smallest as possible for a Ph.D. Thesis, using pdflatex.  The use of no packages (usepackage) would be ideal, if it may be possible.   thank you


Actually , I am not believing that $\frac {1}{∞} = \frac{0}{1}$ because simply $0 ≠ 1$ (we get this if we multiple numerator by denominator) , In the other hand it is very very very small , So I am confused


I have a small command-line hold'em hand generator:  hole_cards = deck.draw(2) h1, h2 = hole_cards print(f'Your Hole Cards: {h1} | {h2}\n')  flop_cards = deck.draw(3) f1, f2, f3 = flop_cards print(f'Flop: {f1} | {f2} | {f3}\n')  turn_card = deck.draw(1)  t = turn_card[0] print(f'Turn: {f1} | {f2} | {f3} | {t}\n')  river_card = deck.draw(1) r = river_card[0] print(f'River: {f1} | {f2} | {f3} | {t} | {r}\n')   Which outputs like this:  Your Hole Cards: ♦Four♦ | ♣Five♣  Flop: ♣Two♣ | ♣Ace♣ | ♦Two♦  Turn: ♣Two♣ | ♣Ace♣ | ♦Two♦ | ♠Seven♠  River: ♣Two♣ | ♣Ace♣ | ♦Two♦ | ♠Seven♠ | ♠Ace♠   Is there any way I could, instead of printing the turn and river after the flop, replace the word flop with turn and then river? I know that I can print the new cards on the same line, but I don't know how to replace the already-printed word "flop" or "turn"


Correct term for stacked / super-justified / variable height text

Meaning like this, where there's a fixed width, and every line is scaled maintaining its aspect ratio to meet the width - including scaling the height (unlike regular justified text).   There might be tweaks to the tracking and kerning, but they're not the core feature of the style, which is the changing text size:      Woah! While finding examples I just noticed we have an almost-identical question already:       But those answers don't give a name for this style, they're just typographic terms, some of which may be used in creating this style, but none of which are this style.   Is there a name for this style, where the size (width and height) is adjusted to make each line equal in width and to bring out certain words?  It's not "justifying", because that doesn't involve changing the size of text, that only changes the letter spacing or occasionally width. It never changes the height. It's not "", which is setting type. 99% of the work of typesetters is not in this style.


Basic operation of a bipolar junction transistor

I've tried really hard to understand the basic operational principle of a transistor. I've referred to many books and been to forums but have never got a convincing answer.  Here are the things I want to understand:   A transistor is similar to a reverse biased diode unless a voltage is applied to the Base.  Since the Emitter-Base junction is forward-biased, there will be conduction of - say - electrons (npn). What happens then? Is it true that these electrons from the Base break the barrier of the Collector-Base junction and then the combined current passes to the Emitter? (IB + IC = IE)  And why is that we are getting more current? Where is amplification? It can't be like creating something out of nothing. I know I'm missing some crucial point here. Can somebody explain me clearly in simple terms?  It has been a week I'm tryin to understand this. :(


How to get a date from string using regex?

In the below code I am able to get open, high, low, close and volume with regex but unable to get day_date.  day_values = "('2019-05-10', {'1. open': '197.4190', '2. high': '198.8500', '3. low': '192.7700', '4. close': '197.1800', '5. volume': '38764368'})" day_date = re.search('(\'(.+?)\'', day_values).group(1) day_open = re.search('1. open\': \'(.+?)\'', day_values).group(1) day_high = re.search('2. high\': \'(.+?)\'', day_values).group(1) day_low = re.search('3. low\': \'(.+?)\'', day_values).group(1)             day_close = re.search('4. close\': \'(.+?)\'', day_values).group(1) day_volume = re.search('5. volume\': \'(.+?)\'', day_values).group(1)   How do I solve this problem?


Prove that $\frac{(n-2)s^2}{\sigma^2}\sim \chi^{2}_{n-2}$

Consider the following simple linear regression model involving the $\epsilon_i$ error term,  $$y_i = \alpha + \beta x_i + \epsilon_i$$  such that,  $$\epsilon_i \sim \mathcal N(0,\sigma^2)$$  we know that if $Z_1, Z_2, ..., Z_n$ are independent, standard normal random variables,   $$Z_i \sim \mathcal N(0,1)$$  then the sum of their squares is distributed according to the chi-square distribution with $n$ degrees of freedom,  $$\sum _{i=1}^{n} Z_{i}^{2} \sim \chi^{2}_{n}$$  Now let's prove that $\frac{(n-2)s^2}{\sigma^2}\sim \chi^{2}_{n-2}$ such that,  $$s^2 = \frac{\sum _{i=1}^{n} \hat{\epsilon}_i^2}{n-2}$$  Proof:  $\require{cancel}$  $$\epsilon_i \sim \mathcal N(0,\sigma^2)$$  $$\frac{\epsilon_i - \cancelto{0}{\overline{\epsilon}}}{\sigma} \sim \mathcal N(0, 1)$$  $$\sum _{i=1}^{n} \left(\frac{\epsilon_i}{\sigma}\right)^2 \sim \chi^{2}_{n}$$  $$\sum _{i=1}^{n} \frac{\epsilon_i^2}{\sigma^2} \sim \chi^{2}_{n}$$  How do I now move from this expression $\sum _{i=1}^{n} \frac{\epsilon_i^2}{\sigma^2}$ which uses the error term $\epsilon_i$ to this expression $\sum _{i=1}^{n} \frac{\hat{\epsilon}_i^2}{\sigma^2}$ which uses the residual term $\hat{\epsilon}_i$?  Note:  I came across this  but I got lost in the second part of the demonstration and I wanted to know if there is a simpler method that would lead to the same answer.


Why conjugate when switching order of inner product?

There is an axiom of inner product spaces that states:   $\overline{\langle x,y\rangle } = \langle y,x\rangle$   Basically (without any conceptual understanding) it seems like all you have to do when you swap the order of the arguments in an inner product space is take their conjugate.   How does this make any sense? I know if we are dealing with an inner product space over $\mathbb{R}$ then the conjugate of a real number is just the real number itself so there is no change. But how does this make sense over the field $\mathbb{C}$?


Why does this for() (Java) statement not work?

So, I try to automate this script for . I don't understand why in this version the automation won't work, in the last piece of code.      BigInteger b = new BigInteger("1");     BigInteger Arr [][] = new BigInteger [20][20];     //add 1 to 20.     for(int i=1; i<=20;i++) {         String I = Integer.toString(i);         b = new BigInteger(I);         Arr[1][i-1] = b;     }   The following piece of code works. So i try automated it, which does not work. Help me find out why.      Arr[2][1] = Arr[1][2];     for(int i = 2; i<20; i++) {         Arr[2][i] = Arr[2][i-1].add(Arr[1][i]);         System.out.println(Arr[2][i]);     }     Arr[3][2] = Arr[2][3];     for(int i = 3; i<20; i++) {         Arr[3][i] = Arr[3][i-1].add(Arr[2][i]);         System.out.println(Arr[3][i]);     }     Arr[4][3] = Arr[3][4];     for(int i = 4; i<20; i++) {         Arr[4][i] = Arr[4][i-1].add(Arr[3][i]);         System.out.println(Arr[4][i]);      }   Here I tried to automate the code. but it gives me an:     Exception in thread "main" java.lang.NullPointerException           at Problem15.main(Problem15.java:45)   for(int c=2; c<20; c++) {     Arr[c][c-1] = Arr[c-1][c];      for(int i = c; i<20; c++) {         System.out.println(Arr[c][i-1]);         Arr[c][i] = Arr[c][i-1].add(Arr[c-1][i]);         System.out.println(Arr[c][i]);     }     System.out.println("hi"); }


Food safety of low temperatures like sous vide and slow cooking

While I really like low temperature cooked dishes, I ask myself whether all microorganisms are killed with these methods. I'm worried that not all parasites and bacteria are killed at 60-70°C.  Is there a table with meat cooking temperatures and the corresponding surviving species that might remain in the products?


Determinant of $\left(\begin{smallmatrix} -bc & b^2+bc & c^2+bc \\ a^2+ac & -ac & c^2+ac \\ a^2+ab & b^2+ab & -ab \end{smallmatrix}\right)$

I started by adding $C_1$ goes to $C_1 + C_2 + C_3$.   After that well nothing seemed good to continue I have tried other steps too but it keeps getting more complex.


Word to describe the way cattle and buffalo consume fodder?

How do you describe the the way cattle buffalo chew ("re-chewing", specifically) their food? There is a specific aspect of their food eating habit which is often related to how people work.


WARNING: SLIGHT NSFW    Uhh...guys, mathematically speaking, how accurate is this comic. From what I remember in High School  $$a^b= \underbrace{\,a\cdot a\cdot  \ldots \cdot a \,}_{b\ \text{ times}} $$ So does that mean that  $$i^i= \underbrace{\,i\cdot i\cdot  \ldots \cdot i \,}_{i\ \text{ times}} $$  How can you multiply a number by itself an imaginary number of times?


How Middle Align a vertical oriented text in Tables

This picture is a part of a table i am using, the terms subcases are vertically written but i cant center them vertically also in the next column terms like A, B are also not vertically centered. I made this table using tabulary package and i am also using this command   \begin{tabulary}{1\linewidth}{J J J J J J J J J J J J J}   to wrap my text in cells of table


I want to write a bash script which takes different arguments. It should be used like normal linux console programs:  my_bash_script -p 2 -l 5 -t 20   So the value 2 should be saved in a variable called pages and the parameter l should be saved in a variable called length and the value 20 should be saved in a variable time.  What is the best way to do this?


This year the LIGO experiments have found evidence of Gravitational waves. In their experiments two black holes merge and give rise to huge ripples in spacetime. Now after the discovery, every scientific seminar I attended on the subject says that this opened up a new era of Gravitational wave astronomy. My question:   Astronomy is usually referred to the observational study of universe, galaxies and stars. Given the gravitational waves we detect are anyway very feeble, I was wondering how is it possible to infer anything related to the structures of universe from these waves?


How do I use "Use" correctly in this sentence?

"I'm not use to this city life" OR "I'm not used to this city life" ?


How to keep playing online videos when screen is locked?

I want to listen to online videos with my mobile phone in my pocket, but there is always something to touch the screen and interrupt the stream.  The only solution I know is to download and save the broadcast or video on my phone before listening to it with a video player app which can be screen locked.  The issue is that I don't want to download any YouTube video before listening to it, so I'd like to find a way that can keep screen locked while playing a video.


Why did Obi-Wan not know about Kamino and Kaminoans?

If you watch Episode 2, you know Obi-Wan is asking his friend from the inn about the dart, and got told it's from Kamino. Then he acts like he knows nothing about Kamino or Kaminoans.  But how can he not know anything about them when there is a Kaminoan Jedi in Episode 1 in the council?    How can there be a Kaminoan council member if no one really knows anything about Kamino?


Hom of finitely generated modules over a noetherian ring

This is an exercise from Rotman, An Introduction to Homological Algebra, which I've been thinking now and then for a few days and I haven't solved it yet. I've decided to ask here because it is bugging me and I don't have any friends also studying this subject (in case it is of any use, I'm an undergraduate).     Let $R$ be a commutative noetherian ring. If $A$, $B$ are finitely generated $R$-modules, then $\operatorname{Hom}_R(A,B)$ is a finitely generated $R$-module.   Here's what I've thought as of yet (maybe the problem is that I haven't been trying to apply the useful theorems...):  First of all, since $R$ is noetherian, it suffices to inject $\operatorname{Hom}_R(A,B)$ into some finitely generated module (in noetherian rings, submodules of f.g. are f.g.).  Now, since $R$ is commutative (or since $R$ is noetherian), a finitely generated $R$-module is a quotient of $R^n$ for some $n$. Then let us write $A\simeq \frac{R^n}{I}$ and $B\simeq \frac{R^m}{J}$. Now we've got:  $\operatorname{Hom}_R(A,B)\simeq \operatorname{Hom}_R\left(\frac{R^n}{I},\frac{R^m}{J}\right)$.  If I had $\operatorname{Hom}_R\left(\frac{R^n}{I},\frac{R^m}{J}\right) \hookrightarrow \operatorname{Hom}_R(R^n, R^m)$ (this is what I tend to think is the wrong direction, but a interesting question-rising path nevertheless) then it would be over since $\operatorname{Hom}_R(R^n, R^m)\simeq R^{nm}$ which is finitely generated.  So I ask myself: can I see $\frac{R^n}{I}$ as a submodule of $R^n$? Because if I could, then doing the same thing for $R^m$ and passing it to the hom, then it would be over. Now, this would be true if the sequence $$0\to I\hookrightarrow R^n\to \frac{R^n}{I} \to 0$$ split. But this (of course) doesn't always happen. But if I somehow had the third module to be projective, or the first one to be injective, then it would happen.  But why would, for example, be $\frac{R^n}{I}$ be projective?  And this is where I got stuck. I'm sorry if this is overly detailed, but I remember reading that it is always good, when asking about a textbook question, to add what you've thought up to that moment. Also, even if my thoughts don't lead to the solution, I would like to know if they are correct!


Is it possible to install an earlier version of Skype on Windows 8?

Windows 8 skype is terrible.  They've removed many buttons, most of the preferences, and have in general made it impossibly oversimplified and difficult to use.  Old Skype was fine when I had windows 7.  Is there any way to get it back on Windows 8?


Why is the 'question record' not shown in the profile?

There are multiple users out there who don't understand why they haven't been awarded with the "curious" Badge.   who had to recieve an explaination of how the index is calculated.  However, what I don't understand is why the index is not calculated by the system and available for the users without the need to be calculated by hand.  It would be much easier and more transparent for the users to know where they stand. There are so many situations in which you can't tell for certain  what your current question record index is and seeing a direct impact would make people a lot more careful to ask badly formatted questions (question ban) or work for a better record in order to earn the curious badge. I think you should have an index of how well you're doing at any time. Same goes for answers and comments.


Why did George Lucas (or whoever else) decide to call Order 66... well, Order 66?  I'm specifically looking for an out-of-universe answer. I already know that the in-universe answer is, "It came after Order 65, and before Order 67."


$(f_n)_n$ a sequence of functions uniformly equicontinuous that puntually converge to a function $f: X\rightarrow Y$, so that convergence is uniformly

Let $X$ a compact metric space and $(f_n)_n$ a sequence of functions from $X$ to $Y$ uniformly equicontinuous that puntually converge to a function $f: X\rightarrow Y$, so that convergence is uniformly.  My question is: to prove that, shall I use the fact that every sequence in X has a subsequence that converge?is it useful for demostrate that?


Can't see text that I'm editing in a chat room

I went to edit my text in a chat room, but I was not able to see the text while trying to edit it. I am only able to see it while I highlight it.   Using Windows 7 Using Google Chrome Using "Grammarly" Google Chrome Add-on (I don't know if it can affect it.)    Examples:


YA book about a young powerful female caster attending a school that trains in magical arts and duels

I read a young adult novel around the turn of the century. This story features a young female protagonist that is very naturally gifted in magic. She is attending a  to learn mastery and control over her gifts.  A lot of her school revolves around magic dueling. The participants are taught to extend their inner aura like a second magical skin, possibly referred to as creating a shield, or . The user can increase the strength of the shield by focusing harder on it, but doing so means you have less ability to be offensive. The amount of energy needed to create a shield was half the energy a foe would need to focus at you to break it.  Ex: Mage A and B are equally matched. Mage A focuses half his power into a shield. Mage B would then need to focus 100% of his power to break A’s shield.  Another aspect I remember is that when dueling, a school master would extend a personal shield on to one of the combatants as a sort of secondary shield that goes underneath the combatants. When one mage broke the others mages personal shield, the school masters shield protects the losers life from harm, and the breaker of the shield is declared the winner.  I distinctly remember one match in which the protagonist is having a duel with another strong student. She creates a wind storm around herself that picks up the sand from the arena floor and makes her impossible to see and thus makes it hard for her opponent to focus on her shield to break it. She then lashes out at her opponent with incredibly powerful strikes with the final strike being so hard it shatters the opponents shield and then breaks the school masters shield as well and stops just shy of killing her dueling partner.  Any assistance on this one? I think my daughter would love to read it.


Windows 10 won't accept Firefox as the default browser

I have recently upgraded my Windows 7 Pro to Windows 10 and basically everything seems to be working fine. Except for the fact that Win10 won't get Firefox as the default browser in the system... It started when I noticed that nothing happens when I click on links in email messages on Outlook. After I checked a few things, I also got to change the defualt browser to Chrome and the links worked. That's when I realized that the issue is with the definition of the default browser on Win10. I should mention that I have used all possible ways to set FF as the default browser in the system - from FF itself of couse, from the settings of the system, from file associations, program association and so on. Nothing changed when I did it for FF. Once I do it for Chrome (in ANY of the mentioned ways), it works exactly like it should. Is it a Win10 issue? Is it an FF issue? What can I do more about this?  UPDATE: I have tried everything that has to do with settings Firefox as the default browser in the system, including going through the Settings of Windows, going from the Settings of Firefox, setting default files and protocols, but nothing helps except for re-installing Firefox. If doing that would have closed the issue once and for all, I would have settled for that, but that's the "solution" after every reboot of the OS! This is very frustrating and I don't know what more I can do about it.


I have a need to collect some duplicate files and want to avoid name collisions. The problem is that this collection of files might be added to by another execution of my script before the files are cleaned out and just want to continue to increment the number.  I decided on a simple until loop to increment the number like so.  until [[ ! -f ${PWD}/DUPES/${num}-$1 ]]; do num=$((num +1)) done mv --no-clobber $1 ${PWD}/DUPES/${num}-$1   I can't imagine ever exceeding 1k files in an extreme example, so my questions are...  Is this a terribly inefficient way to achieve this? Should I be parsing the existing files to get the highest leading number to start incrementing from there, or is this ok for the extreme example I put forth?  Or is there a better way all together?


Writing output of a For Loop to .txt file

#!/bin/bash  for i in $(cat containers2.txt); do     swift list -A http://sslabapi/auth/v1.0 -U auto02 -K    FfiBftkjgS8hnQn79Arj7PiHfvtsgn $i > js.txt done     for a in $(cat js.txt); do             swift stat -A http://sslabapi/auth/v1.0 -U auto02 -K FfiBftkjgS8hnQn79Arj7PiHfvtsgn $i $a | xargs | awk '{if ($12 > 10000) print $2, $4, $6, $12, $15, $16, $17, $18}' done   Above is a script I am working on. I apologize for how ugly it is, for I am not an expert with Bash Scripting. Ultimately I need to complete a loop where the containers.txt file has a list of containers like this:  5f7f720f-7563-031b-a002-9059f5c000b2 64366a18-e590-44cf-b99c-13b7587b34b5 6785038a-fd74-43c0-afcb-ddf25f251363 6952e11a-69a2-4988-81ff-10910a274d69 69f7d0f9-9a63-4d29-8e84-1c06b5fe892f 6a9480b8-84c8-4ab5-a82e-5576ceb1df7f 6bb37f24-1605-2aac-2ba2-c1e0d49f4ec7 874600f4-a8b2-4bf7-bca8-c75dac676f03   Each container has a list of objects as listed below:   ffd5eef3-2b75-4d4f-b30c-b9836b32a34c.FR.02  ffd5eef3-2b75-4d4f-b30c-b9836b32a34c.FS.02   Some containers have more objects then others. But in this script I am only getting the output of the final container written to the js.txt file. Also I am only getting the final output of the last objects in the final container. I am guessing the js.txt file is being overwritten each time the loop runs, so only the last container is present in it. Which makes sense to why the final output is only the objects from the final container.   Is there a way to output each object into js.txt one line at a time? Or am I going about this the wrong way?  Thanks


How the operator (is) works with tuples and lists

Why when I compare two equal tuples through the operator (is) I get a different result than when I compare two equal lists? (one is True an the other is False)  Nothing really... i am starting with python and i do not want to leave my doubts :)  a=(1,2,3) b=(1,2,3) c=[1,2,3] d=[1,2,3] print(a is b) #True print(c is d) #false   I expected that both were False :(


I have a data file which looks like this:  1   256 2   197 3   190 4   188 5   219 6   169 7   179 8   181 9   182 10  178   where the first column are timesteps and the second column contains the number of iterations an algorithm needed in the corresponding timestep.  I plot this with the first column as the x axis and the second column is the graph. Now I want to add the average amount of iterations over all timesteps and plot it as well.  Is there a way to calculate the mean of a column within pgfplots and use this value in the same plot like this:  \addplot[samples=2] {\meanValue};


Can a single player world be opened to people that aren't on my network?

is there a way to make my single player world open to others? I know that there's LAN, but I'm talking about other people from farther away. For example, if I'm playing in Chicago and I want someone in Nebraska to be able to play my single player world, is there a way that I can make that work?


Why would turning off a sink faucet stop the shower?

We observed a really weird behavior this morning.   While showering, if any sink faucet is turned on anywhere in the house, the shower continues without any problem. However, when that sink is turned off, water flow in the shower drops by over 90% to a trickle. Turning off the shower and back on restores water flow to normal.   We've never had this problem with the shower before. (The shower plumbing was all completely replaced 6 months ago as a part of a remodel)  Is there any explanation for this?


Determine the convergence of $\sum_{n=2}^{\infty} \frac{(-1)^n}{(-1)^n+n}$

I've been really stuck on this infinite series.  $\sum_{n=2}^{\infty} \frac{(-1)^n}{(-1)^n+n}$  Trying to determine if it converges or diverges.  As far as I've got is seperating it into two partial sums (odds and evens) but even this doesn't help me.  Any ideas?  Thanks


Setting error bar line width using \pgfplotsset

In the following MWE, the lines and vertical error bars have the correct width, but not the horizontal bars. How do I set them to 'very thick'? Also, is there a way to control their length? Finally, is there a way to set the error bars to solid, while having the line being dashed?  \documentclass{article} \usepackage{pgfplots} \pgfplotsset{compat=newest} \pgfplotsset{/pgfplots/error bars/error bar style={very thick}} \pgfplotsset{   every axis plot/.append style={very thick, black}, }  \begin{document} \begin{tikzpicture}   \begin{axis}     \addplot [dashed, mark=asterisk, error bars/.cd, y dir=both, y explicit]     table [x=x, y=y, y error=y-err]{%       x y y-err       0 0 0.5       1 1 0.5       2 2 0.5       3 3 0.5       4 4 0.5     };   \end{axis} \end{tikzpicture} \end{document}


Limit mouse movement to 2 montiors? (4 monitors all together)

I have 4 monitors, two of which are kiosks and are just playing looped powerpoints but the other two I need to have interactive. How can I limit my cursor movement to just monitors 1 an 2 an not allow any interaction with 3 and 4?


I'm over the MAGI limit for 2018 for the Roth IRA I already contributed to. Now what?

At the beginning of last year, I contributed the maximum amount to my Roth IRA, as I typically do.  Late in the year, I received a very unexpected and very large bonus.  I realized when I got my 1040 this week that the bonus will put me over the MAGI limit for Roth IRA contributions.  What do I do now?  I'm single and do not currently have a traditional IRA or 401K, if any of that is relevant.


appending into middle of a string using sed

I am completely new to sed script. I want to make a script so that it asks user to enter value to be inserted in file. I am not able to find the correct code  so the line I have in the text file looks like this  path =   I want to input path from user so the line looks like:  path = /dev   Through trial and error I only have:  read -p "Enter path name: " PT echo "$( sed -i '/path/ s/.*/& $PT/' textfile )"   which gives  path = $PT   can you help me with correct code


Show that there does not exist any non-zero homomorphism f : S3 → Z3.

I am not the best at group theory, a lot of concepts are still a little fuzzy for me so I'd really appreciate explanations that are in detail.  Currently trying to prove this using the first isomorphism theorem, I know that the kernel has to be non-trivial because f cannot be one to one.


Are these sentences correct? And what's the difference?     1- The last few days were a nightmare for me. I don't want to think about those days.      2- The last few days have been a nightmare for me. I don't want to think about those days.   Note that the bad days are gone.


Second parameter of e (event interface) in onChange = (type) => (e) => How is this being passes from the OnChange (is it by default)

const onChange = (type) => (e) => {      const [value, setValue] = useState({         StartDate : new Date("2021-03-24T23:59:59"),         EndDate : new Date("2021-03-24T23:59:59"),         Seperate : false         });       if (type == "StartDate" || type == "EndDate") {       console.clear();       setValue({         ...value,         [type]: new Date(e),       });     } else {       setValue({         ...value,         [type]: e.target.value == "on" ? !value[type] : e.target.value,       });     }   };       <Form.Control as="select" onChange={onChange("Consolidation")}>     <DateTimePicker onChange={onChange("StartDate")}     onChange={onChange("StartDate")}  Attempting to understand %100 the above.  And I am confused by one item in the above.  What is the purpose of the second (e) in the above function?  I know this is the event handler, yet how is this passed to the onChange function from the form controls, being it is only defined with the type parameter. I guess the additional => (e) is confusing me.  Thanks for your time.


Prove there exist 135 consecutive integers that each have a perfect cube $>1$ that divides it.

As of 22:13, the answer below does not satisfy the constraints of my question, so I'm still accepting answers.    Prove there exist 135 consecutive integers, $x_1, x_2, ... , x_{135}$, such that for each of these integers, $x_i$, there exists a number $k_i$ such that $k_i>1$ is a perfect cube where $k_i | x_i$.    I was told that I could use GCRT to help with this. I got stuck after rewriting the given statement as a system of linear congruences.


Is the following correct:     There's a sofa, two armchairs, a TV and a big cage for our parrots.   Or should we change it to:     There's a sofa, there are two armchairs, there's a TV and a big cage   for our parrots.


How can I change the perspective of an image with nodes?

I'm making a class scene, and I've made a simple projector that displays an image on a whiteboard, everything works just fine, but the image has the perspective that is normally cancelled to look squared in real life projectors. So is there a way to cancel out that warping with nodes? I'd prefer not to manually correct the images somewhere else.  If it wasn't clear, I'm trying to scale the top part up horizontally.  This is the node setup is very simple, just an image connected to the emission color with some mapping stuff to remove the pincushion effect.


The fractional parts of the powers of the golden ratio are not equidistributed in [0,1]

Let $$a_n=\left(\frac{1+\sqrt{5}}{2}\right)^n.$$ For a real number $r$, denote by $\langle r\rangle$ the fractional part of $r$.   Why is the sequence $$\langle a_n\rangle$$ not equidistributed in $[0,1]$?


How to escape curly brace in a dynamic string variable, which is used in String.Format?

How to escape curly braces in a dynamic string variable, which is used in String.Format?   Edit 1  I am aware of how this can be handled when the value of the string is known. for e.g.  string someStringVar = "This is a random string {0}. Blah {{ Blah {{ Blah }}"   But how to handle it when I am not aware of the strings value. for e.g.  string someStringVar = GetValueFromXmlFile();   In the above code, GetValueFromXmlFile method could return a string with a valid placeholder like {0} but could also contain characters like { or } which are not placeholders? In such a case should one escape { or } without escaping valid placeholder like {0}?


Display text starting at a specified line

I'd like to check /etc/passwd      $ cat -n /etc/passwd          1  ##          2  # User Database          3  #           4  # Note that this file is consulted directly only when the system is running          5  # in single-user mode.  At other times this information is provided by          6  # Open Directory.          7  #          8  # See the opendirectoryd(8) man page for additional information about          9  # Open Directory.         10  ##         11  nobody:*:-2:-2:Unprivileged User:/var/empty:/usr/bin/false   As we see, the firt 10 lines are commented, the result I desire some command like      $ cat -n [11:] /etc/passwd      nobody:*:-2:-2:Unprivileged User:/var/empty:/usr/bin/false           root:*:0:0:System Administrator:/var/root:/bin/sh      daemon:*:1:1:System Services:/var/root:/usr/bin/false      _uucp:*:4:4:Unix to Unix Copy Protocol:/var/spool/uucp:/usr/sbin/uucico   How to accomplish it?


iPhone 4S speaker not working for apps but works for ringer

I have an iPhone 4S and the speakers are not working for applications. The speaker works when doing voice calls on speaker phone, adjusting the ringer, and other default things.  However, when trying to have audio for YouTube and other applications it does not work.  It wasn't working for IOS 6.1.3 and I have now upgraded it to 7.0.4 with no luck. I then restored again with no luck.  I believe the fact that it works for the speaker phone and ringtone would suggest it is not a hardware problem but a software problem.  Any suggestions?


Let $f(z) = f(z^2)$, for all $z\in\mathbb{D}$ with $f(1) = 1$, then which of the following is incorrect?

Let $f(z)$ be analytic on $\mathbb{D}$ = {${z\in\mathbb{C}:|z-1|<1}$} such that $f(1) = 1$, if $f(z) = f(z^2)$ for all $z\in\mathbb{D}$, then which of the following statements is NOT correct?   1) $f(z) = [f(z)]^2$  2) $f(\frac{z}{2}) = \frac{1}{2}f(z)$  3) $f(z^3) = [f(z)]^3$  4) $f'(1) = 0$  This question is also in  .  If we will assume $f(z)=1$ for all $z\in\mathbb{D}$ then this function clearly satisfies all the hypothesis so (2) is incorrect. I strongly believe that the only function which satisfy the above hypothesis is $f(z)=1$. But how will I prove this?


I find it distracting, so I decided to try get rid of it by doing 20 reviews, but it kept coming back. It should be enough that review is visible on every page right?    It says there are 6 reviews pending in the image above.


I have a 9 speed specialized sport comp road bike.  my chainrings are 50 x 34t and i wanted to possibly change them to a 53 x 39t to increase my speed. it has shimano cassette/components and a truvativ iso flow crank arm. my question is would most 53x39t chainrings match up with my crank? or would it be better just to get a whole new crankset?


How can I ensure my exit from the US by land is recorded?

Seeing as the US does not perform border control on exit (save for occasional spot checks, usually when traffic is moving slowly at the border), how do I make sure my exit by land is recorded so that I'm not incorrectly flagged as an overstayer?  When exiting the US by air or sea, this is not a problem, as airlines and shipping companies send passenger records to US authorities. What about exiting by land though?


Giving numbers to each grid cell by rows in ArcMap?

I want to assign cell numbers to each grid cell (only having a point in the middle) beginning with 1 at the upper left corner, numbering consecutively by rows. The cells that I want to number are shown below.  Could you help me do that?


What would happen if something were insured twice?

This is purely hypothetical and I'm not sure how it would work.  Let's say that I own a house and I insured the building and its contents. Then I  contacted another insurance company and I insured the building and contents AGAIN.  I now own two policies, both of which guarantee to replace the contents and the value of property if a set of conditions are met. A common example would be an accidental fire.   Oops, the house burns down. Does this mean I could then claim on both policies and I'd end up with both the money to repair/replace property AND that amount of money again?    My 'common sense radar' tells me that this is ridiculous and clearly wouldn't work but I can't prove that logically.  So here's the question.  What would happen if the conditions were met on two insurance policies on the same thing?


If $f_n \to f$ and $g_n \to g$ in measure and $\mu$ is finite, then $f_n g_n \to fg$ in measure

This is Problem 3.1.5 in Cohn's Measure Theory, 2nd edition.  Let $\mu$ be a measure on $(X, \mathcal A)$, and let $f, f_1,f_2, \ldots$ and $g,g_1,g_2,\ldots$ be real-valued $\mathcal A$-measureable functions on $X$. (a) Show that if $\mu$ is finite, if $f_n \to f$ in measure, and $g_n \to g$ in measure, then $f_n g_n \to fg$ in measure.  With some effort, I was able to work out a direct proof, similar to the one outlined in . After re-reading the section, I came up with an alternative argument similar to the one used by Cohn to prove another theorem. It results in a much quicker proof, and almost seems like a magic trick. I want to make sure that my argument is correct. I use the following results, proved by Cohn in this section, for real-valued measurable functions:  Proposition 3.1.3: If $f_n \to f$ in measure, then there is a subsequence such that $f_{n_k} \to f$ almost everywhere. Proposition 3.1.2: If $\mu$ is finite and $f_n \to f$ almost everywhere, then $f_n \to f$ in measure.  Here is my proof: Let $\{n_k\}$ be any subsequence of $\mathbb N$. Then $f_{n_k} \to f$ and $g_{n_k} \to g$ in measure, so by Proposition 3.1.3 there is a subsequence $\{n_{k_j}\}\subset \{n_k\}$ such that $f_{n_{k_j}} \to f$ and $g_{n_{k_j}} \to g$ almost everywhere. (To see this, take a subsequence of $\{n_k\}$ that works for $f$. Then that subsequence has a subsequence which works for both $f$ and $g$.) Therefore $f_{n_{k_j}} g_{n_{k_j}} \to fg$ almost everywhere. As $\mu$ is finite, Proposition 3.1.2 implies that $f_{n_{k_j}} g_{n_{k_j}} \to fg$ in measure. Now here is the magic part: Suppose that $f_n g_n$ does not converge to $fg$ in measure. Then there is some $\epsilon > 0$ such that $\mu\{|f_n g_n - fg| > \epsilon\}$ does not converge to zero. Thus there is some $\delta > 0$ such that $\mu\{|f_n g_n - fg| > \epsilon\} > \delta$ for infinitely many $n$. In other words, there is a subsequence $\{n_k\} \subset \mathbb N$ such that $\mu\{|f_{n_k} g_{n_k} - fg| > \epsilon\} > \delta$ for all $n_k$. Clearly this subsequence cannot have any further subsequence $\{n_{k_j}\}$ for which $f_{n_{k_j}} g_{n_{k_j}} \to fg$ in measure, but this contradicts what we showed above. Consequently, $f_n g_n$ must converge to $fg$ in measure.  Is this argument legitimate? It almost seems too easy.


Can I use Openlayers Plugin with a different Datum/Projection?

There is probably already a post for my problem, but after long searching, I could not find a solution for my issue.  I am working with QGIS und I am using the following projection/datum: MGI / Austria GK East (EPSG:31256) (+proj=tmerc +lat_0=0 +lon_0=16.33333333333333 +k=1 +x_0=0 +y_0=-5000000 +ellps=bessel +towgs84=577.326,90.129,463.919,5.137,1.474,5.297,2.4232 +units=m +no_defs)   I just want to add a layer form the openlayers plugin. For example Google satelite. the Google satelite uses the following projection/Datum:  WGS 84 / Pseudo Mercator (EPSG:3857) (+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext  +no_defs).  The Problem that I am facing with, is that I can not get the Google layer in the same projection with my other layers (EPSG:31256)! They are not overlapping correct!  Is there a way to do this?


Broken layout for flagging for moderation attention textbox

The layout of textbox for the in need of moderator intervention flags is broken, in that its content overflows it's outer <div id="popup-flag-post"> container. My browser is Firefox 31.7.0 (technically Iceweasel 31.7.0) on Debian 7.8 Wheezy.   I tried this on both a random Stack Overflow question:    as well as a Travel SE answer:


Why simple string comparison giving FALSE result?

I cast an object into a JSONObject then get the string and compare it with "play_audio." The IF statement gives a false result even though my log is giving me correct string - what is going on?                  JSONObject data = (JSONObject)args[0];                 String command = null;                 try {                     command = data.getString("command");                 } catch (JSONException e) {                     e.printStackTrace();                 }                 Log.i(TAG, "<<<<---- RECEIVING COMMAND ----->>> " + command);                 if (command == "ping_audio") { //WHY IS THIS FALSE?                     Log.i(TAG, "<<<<---- PLAYING AUDIO ----->>> ");                 }   logcat  <<<<---- RECEIVING COMMAND ----->>> ping_audio


What am I doing wrong here with cron on boot?  Example:  To launch manually: screen -S example ./script.sh To recover manually: screen -x example  now, I just try to do the same thing (well, the launch part) using cron on boot  @reboot cd /home/administrator/script && screen -S example ./script.sh  I think it works without screen. For example:  @reboot cd /home/administrator/script && ./script.sh  but I also need this to run in the background, independent of the terminal. I have tried other options such as init, init.d, but there seems to be a lot of confusion out there on how it all works on which versions of linux. If you can fix my error above or show me a better solution, that would be great.  I am using Ubuntu 12.04.2 LTS  Thanks  * UPDATE *  So in response to Jan Wikholm, I have tried the absolute path and that completely fails.  Example  If I test this in the console:  screen -S example /home/administrator/script/script.sh  The script does not execute. Am I missing something conceptual here?  I get the screen error message [screen is terminating] immediately  * SOLUTION *  Finally figured it out. The issue with screen was the path to the executable.  Here is the final crontab entry that works like a charm  @reboot cd /home/administrator/script && /usr/bin/screen -dmS example ./script.sh  Thanks for the help Jan


I am inserting face on a rectangle. I want to create a picture frame and I want equal thikness for all "the outer faces" (not like my print screen)[![enter image description here]


A particular disease affects 0.1% of the population.   The test is 95% accurate.   You test positive.   What is the chance that you have the disease?  How I approached the problem: Since I already tested positive, and the question clearly states that the test is 95% accurate, there should be a 95% probability that I have the disease. But, a YouTube  says that the chance I have the disease is 2%. How is my reasoning wrong?


Using the name of a table contained in a column of another table?

I have a table called MyTable with varchar columns named SourceID and ReferenceID, where SourceID contains a table name and ReferenceID contains a key value for the source table. Is it possible in a query to refer to the source table's row assuming I know the name of the key column that matches the value in RefrenceID? Sample: SELECT     * FROM     MyTable as MT INNER JOIN MT.SourceID as Src ON MT.ReferenceID = Src.InstanceID  This doesn't work, obviously.  But is there a way to do this as opposed to dynamically building the SQL statement using the values of SourceID and ReferenceID and then executing the query?  More specifically, is there a way to make MyTable.SourceID in the example above be usable within the JOIN? Further considerations I found , and it has a trick like follows: select   E.EmployeeName, coalesce(s.store,o.office) as Location from   Employees E left outer join    Stores S on ... left outer join   Offices O on ... where   O.Office is not null OR S.Store is not null  The WHERE clause simply helps the outer joins behave like INNER JOINs.  This would work well enough if there were a limited number of table options and they all had UNIQUE constraints.  This gets me part of the way there but but I really want is to have the table names in the JOINs to be based on a column in Employees. I haven't given up yet. Any and all help is greatly appreciated.


Loss in energy by light after reflections

Energy of light is proportional to its frequency.So if light loses energy on reflecting off a surface then why doesn't it change its colour?


The expected behaviour for this is to print 2949 is the magic number! when it hits 2949, yet the loop doesn't. The loop seems to start at 19, then jump to 513920 - why is this?  magicNumber = 2949  for x in range(0, 100000000):     if (x is magicNumber):         print(x, "is the magic number!")


I purchase a blue and red toad house in Mario Run. What is the point of purchasing those houses? Does it give you more toads or anything?


I have recently updated my PHP version to 5.4 and my mysql version to 5.5      [root@**** ~]# php -v PHP 5.4.31 (cli) (built: Jul 25 2014 07:41:53) Copyright (c) 1997-2014 The PHP Group Zend Engine v2.4.0, Copyright (c) 1998-2014 Zend Technologies   When i enter my PHPMyAdmin i get the following warning:  Centos Your PHP MySQL library version 1.5.73 differs from your MySQL server version 5.5.39.   What can i do to get rid of this warning?  As you can see my mysql version is correct:      [root@***** ~]# mysql -u root -p -e 'SELECT VERSION();' Enter password: +-----------+ | VERSION() | +-----------+ | 5.5.39    | +-----------+   Update  i have tried the following:      [root@*****~]# yum update php-mysql Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile  * base: mirror.fysik.dtu.dk  * extras: mirror.fysik.dtu.dk  * updates: mirror.fysik.dtu.dk  * webtatic: nl.repo.webtatic.com Setting up Update Process Package(s) php-mysql available, but not installed. No Packages marked for Update


How to upgrade MySQL database schema in respective to sprint releases?

let say we have a Qt/qml based desktop application, this is using mysql as local db .   Note: We will be releasing the new build every 2 weeks.  Here the Problem is, There is a chance of changes in local db like new column added, removal of some fields, new table added, deleted. So due to this changes all the time we are updating entire DB. we can say deleting the entire database and updating with new schema. so every time we are losing old records, because we are not updating only having changes in schema level.  Direct straight forward answer: We can compare two schema with (old_release.sql - new_release.sql) their changes, based on the changes result we can create one alter query instead of entire table changes.This can be possible for current build to immediate next build( n to n+1 ) or current build immediate lower version build ( n to n-1 ). But not possible for [n to n+3] or [n to n-5]  But here the problem is, Let say one client is using version_1.0 build, we wants to upgrade him to version_1.1 means no problem every direct release we have alter query file.We can use this to solve. But if the client is using version_1.0 and we wants to upgrade him to version_2.5 means we does not have any alter query compatibility between version_1.0 - version_2.5 we only having version version_2.4 - version_2.5. That means we can have, n to n+1 n to n-1  not for, n to n+2.  Note: some point there is chance of revert also e.g - version_2.5 to version_1.0  So Question is, Is there any way to understand differences between two schema's ? Any tool ? Any algorithm ?


Could you explain for me what is "likelihood principle (from R.A. Fisher)" without using any (or too serious) mathematical language? What will be the difference between "it is likely" and "it is probable" if we follow this principle?


Can we map a complete metric space to $\mathbb{Q}$?

The question I am trying to answer is this: Given a complete metric space $(X,d)$, in which all of the points are accumulation points. Find if there is a one-to-one and onto map $f: X \rightarrow \mathbb{Q}$. My initial thoughts are: Given that $(X,d)$ is complete, we know that all Cauchy sequences in $X$ have a limit also in $X$. We can easily prove that $\mathbb{Q}$ is not complete, since we can easily find a sequence in $\mathbb{Q}$ which has a limit in $\mathbb{R}\setminus\mathbb{Q}$. So my thought is that there is no such map $f$. But how do I formally prove it?


For which values $r, s \in \mathbb R$ is the set $\{u, v, w\}$ linearly independent?

$$u = (r,1,1), \ v = (1,s,2s), \ w = (1,2,2)$$  I know to assume the set will be linearly dependent, equate them to the $0$ vector and find the values not equal to what $r$ and $s$ is. But I can't seem to reduce the matrix to echelon form.  I've gotten to the point of:  $$     \begin{pmatrix}     r & 1 & 1 \\     1 & s & 2 \\     1 & 2s & 2 \\     \end{pmatrix} $$  $R_2 = R_2 - R_3$ $$     \begin{pmatrix}     r & 1 & 1 \\     1 & -s & 0 \\     1 & 2s & 2 \\     \end{pmatrix} $$ $R_3 = R_3 +2R_2$  $$     \begin{pmatrix}     r & 1& 1 \\     0 & -s & 0 \\     1 & 0 & 2 \\     \end{pmatrix} $$  EDIT: Thank you @LordSharktheUnknown  $R_3 = r \times R_3 - R_1$  $$     \begin{pmatrix}     r & 1 & 1 \\     0 & -s & 0 \\     0 & -1 & 2r-1 \\     \end{pmatrix} $$  And I'm stuck. I know $s ≠ 0$ for it to be linearly independent but I have no idea how to reduce the rows any further to get to $r$ by itself.  Any help is appreciated.  Thank you.


Windows explorer slows down during startup, how to trouble shoot?

Lenovo laptop running Windows 7 Home Premium.  My windows explorer runs VERY slowly.  e.g. a RMB on anything in the right hand pane or on the desktop takes 10 seconds, even selecting objects (files or folders) takes 10 seconds.  However, selecting folders in the left pane of the explorer (the tree) or in the top (where the "url" would be) has instantaneous response.  This is with respect to files local to my hard drive, the CPU utilization is low to zero (though the explorer process jumps up to 25% utilization during the selection - on a 4 CPU system).  Interacting with icons in the taskbar is also slow (10 seconds per operation).  When I rebooted this morning, I caught the taskbar while the log in process was still happening, and it responded immediately, I opened an explorer - no delay in interacting.  Then all of a sudden the 10 second lag happened again.  So it appears that something I've installed and have running is causing this.  What is a good way to track this down?  Other than re-imaging my computer, or just blindly uninstalling everything one-by-one?  My startup folder has only one item in it (Dropbox), so there must be some other place where other programs are launched.  Edited to add: The problem in this case happened to be MS Office's Grooveex.dll, which was disabled by configuring MS Office 2010 and disabling the sharepoint (I think, I disabled a few things).   from the duplicated question really helped, specifically the autoruns - which let me look at what specific things were autorun that specifically affected Explorer.  That was perfect.


I have a xml file as below  <?xml version="1.0" encoding="UTF-8"?> <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">  <url>   <loc>https://ezinearticles.com/</loc>   <changefreq>hourly</changefreq>   <priority>1.0</priority>  </url>  <url>   <loc>https://ezinearticles.com/submit/</loc>   <changefreq>weekly</changefreq>   <priority>0.3</priority>  </url>  ...................   I want to use xpathin lxml module to get URL from all  tag. I implemented it as below code but it didn't work. The result is empty list  from lxml import etree parser = etree.XMLParser(ns_clean=True) xmlfile = "sitemap1.xml" xmlobj = etree.parse(xmlfile, parser)  loc = xmlobj.xpath('//loc[text()]')  print(loc)   Can anyone help me fix my script ?


I installed MySQL using sudo apt-get. Now I need to remove it from my system.  How can I do that?


I am struggling to install my iBurst USB modem so I can access the internet.


This actually triggered me in my mind from . After some playing around I notice that the relation $a^{\log_b x} = x^{\log_b a}$ is true for any valid value of $a,b$ and $x$. I am very inquisitive to see how this holds ?


SP2013 & Responsive Design - How to do it right?

I'm a SharePoint developer and also skilled in web design. My current task is to implement a responsive design along with a branding in SharePoint 2013 environment  Now I am in the situation to choose which one I would use to implement a responsive design in SP2013 and so I collected pro's and con's for each technology.  What do you think? Are there important aspects I'm missing? Are there other solutions which are better suited for realizing this?


Vertical alignment is wrong for rep in new top bar hamburger menu

The site names and rep are not lined up correctly on the new top bar hamburger drop down:    Windows 7 Home Premium 64 bit, Firefox 56.0


fmod() returning the same value in my simple C++ bank program

I decided to try learning to code again for the upteenth time and I'm currently trying to refresh my memory by creating a banking program where a user can withdraw and deposit money. I'm trying to create a function that checks if a user input is a number that goes beyond the cent value and then prompts them to re-enter if so. Unfortunately, when I run the program it will always tell me that there is an invalid entry. #include <iostream> #include <cmath>  using namespace std;  // The following is the function spoken of. double yagoof(double c) {     double cent = .01;     double rem = fmod(c, cent);     cout << rem << endl;      while (rem != 0) {         cout << "Invalid entry. Please enter a number rounded to the nearest cent.\n\n";         cin >> c;         rem = fmod(c, cent);         cout << rem << endl;     }     return c; }  int main(){ ... }  I added the "cout << rem..."s after getting frustrated and wanting to see if I can figure something out. It will always tell me that rem is '.01'. I guess I'm curious as to what I did wrong here. I've reviewed it in my head a few times and I'm not getting anywhere. I can post the whole code if needed, I just didn't do it now because it has a bunch of notes.


How to prove $\det \begin{bmatrix}A & B \\ C & D \end{bmatrix} =\det(AD-BC)$, where $A, B, C,$ and $D$ are $n\times n$ and commuting.

I can solve for the cases in which $C=0$ or $B=0$. But I cannot find any idea for the case in which both $B$ and $C$ are nonzero matrices.


Lagrange Multiplier In Proving AM-GM inequality

I am dealing with a question in Stewart Calculus Book which states the following: Using Lagrange multiplier, find the maximum of the function $$f(x_1,x_2,...,x_n)=(x_1x_2...x_n)^{1/n}$$subject to the constraint$$\sum_{i=1}^{n} x_i=c$$,where $x_i$'s are all positive, and use this to prove the AM-GM inequality. Actually in AM-GM inequality, it holds for all nonnegative numbers, but I think the author wants to get rid of the case where $x_i$'s are all zero, where Lagrange multiplier can no longer be applied. And the result I obtained is: $f$ will have its maximum/minimum (the arithmetic mean), or even saddle point at $(\frac{c}{n},\frac{c}{n},...,\frac{c}{n})$, since Lagrange method gives no definiteness on the behaviour of the critical points found (whether max, min, or saddle). And my question is: In this case, how do we show that the point I found gives the maximum value of the function? My teacher gave me an argument that said "the minimum value would be some place very near to $0$, so the arithmetic mean will not be the minimum value". But I think the argument is not persuasive enough to explain why the arithmetic mean is the maximum value. So, I hope that there will someone who are willing to give their opinions on this. Thanks.


It's been like this for me since my first day on SE.  While typing text into bounty comment text field, when the text stops fitting, the text field (or the whole pop-up window even) scrolls to the right a bit to maintain visibility of the last few characters, shortly after that it forcefully word-wraps while leaving the scroll position slightly to the right, and creates the following visual artifact:    I'm using Firefox Aurora and this has been my experience for a long time.


I am trying to prepare a few of my images for printing purpose. I have never printed images before, so this is my first time.  Most of my pictures are taken by a drone. The resolution says 3000x4000, with 300 ppi. I have edited  it in photoshop, added a layer for high pass filter and exported it as a jpeg with 100% quality.  However, when I open the exported jpeg file, and go to its properties, it says horizontal resolution 96 dpi and vertical resolution 96 dpi. I don't know why this is happening and I am confused. Can someone please help?


How to rename multiple files in a way that each name would be img_NNNNNN format?

I have thousands of images. Their names is as follows:  img_1 img_2 img_3 ... img_36000   I would like to covert them into that (respectively):  img_010251 img_010252 img_010253 ... img_046250   Is there a quick solution for that in Ubuntu 18.04?  Note: The length of the numbering part must be 6! (NNNNNN)


Scope of parameter in a function that contains promise calls

Does a fixed parameter, one that does not change once it is passed to a function, stay in scope for promise calls within the function.  For example, can I trust x in the function below?  someFunc(1); someFunc(2);  function someFunc(x){     somePrmsFunc.then(function(){         somePrmsFunc.then(function(){             if (x == 1)                 alert(x);         });     }); }


I have 4 GB ram.. what should be the perfect swap partition size?

I heard that swap memory partition should be double the size of ram.. is it true? so I have to keep 8 GB swap space? I'm gonna install Ubuntu gnome 13.04.


How to do SEO for database driven web? Asp.net

Hi to everyone and thanks in advance for your time reading this question.  Im kinda new on this SEO stuff and there is something that I can't figure out how it works despite all the readings that I did.  I've developed a new website which allows users to add recommendations for every kind of bussiness, places, professionals, etc, so other people can see if travel to X place is worth it for example.  From what I've read so far (and from what I've understood, which are actually two different things haha) its important to make user and search engines friendly URLs and have proper keywords, title and h1 tags.  (I've read this post  and a few more)  That's not a problem because I can do that on server-side code, but what I actually don't understand is how Google shows pages that collect info from databases on his search results.  Lets put an example just to detail this a little bit more.  If we go to Google and search for "abercruz paginas amarillas" google show us a link that send us to a page from "paginasamarillas.com" which has all the details about that store.  Instead if we go to Google and type, "abercruz yousug" (which is my page) nothing shows up. I know that it could take a few days to Google to index my page but I don't understand HOW could Google "search" into my database (or page, or whatever) to end with the correct URL which shows the details of that Commerce   If someone could explain me that or help me a little bit understanding how to rank content that is generated from a database I will very grateful.  Thanks again!


Using 'her' vs. 'its' to refer to a country

I am currently reading Liddell Hart's "History of the Second World War", and I'm wondering why he sometimes uses her/she when talking about Japan. In my understanding of English, it should be its or their (if you want to refer to the Japanese people).  For instance:     From 1931 onward the Japanese were aggressively engaged in expanding their footholds on the Asiatic mainland at the expense of the Chinese, ...   makes sense to me, but:     It is remarkable that she deferred striking for more than four month, while trying to negotiate a lifting of the oil embargo   or     Until early in 1941 Japan's plan in case of war against the United States was to use her main fleet in the southern Pacific in conjunction with an attack on the Philippine Islands, ...   does not.  Can somebody explain why Japan is female, and are there more countries for which her should be used?


How regression trees split, when all the Features and target have only continuous values

Can anyone please explain how splitting is performed in regression trees when we only have continuous features. I have referred to different papers, but all I could find is formulas or theorems.   Can someone please explain, with an example, how we can build a regression tree from scratch?  That would be a great help.


Can any number of the form $2p$, for $p>3$ a prime, be written as the sum of two distinct primes?

I think Goldbach's conjecture is quite well-know at this point, but there is no problem restating it: any even integer greater than $2$ can be written as the sum of two prime numbers.  But what about distinct prime numbers? For every even integer $n$ that does not equal $2p$, for $p$ a prime, Goldbach's conjecture obviously implies that $n$ can be written as the sum of two distinct prime numbers, but the question in the title remains: what if $n=2p$? (Ignore $p=3$, which clearly fails...)  I tested all prime numbers up to 10.000.000 and found no exceptions.


Showing that a one-to-one linear transformation maps a linearly independent set onto a linearly independent set

Problem 4.3.32 in Linear Algebra, Lay:  Let $V$ and $W$ be vector spaces, let $T:V\to W$ be a linear transformation, and let $\{\mathbf{v}_1, \dots , \mathbf{v}_p \}$ be a subset of $V$. Suppose that $T$ is a one-to-one transformation [...]. Show that if the set of images $\{T(\mathbf{v}_1), \dots ,T(\mathbf{v}_p)\}$ is linearly dependent, then $\{\mathbf{v}_1, \dots , \mathbf{v}_p \}$ is linearly dependent. This fact shows that a one-to-one linear transformation maps a linearly independent set onto a linearly independent set.  All I can think of doing: If $\{T(\mathbf{v}_1), \dots ,T(\mathbf{v}_p)\}$ is linearly dependent, then there exist weights $c_1, \dots, c_p$, not all zero, so that $$c_1 T(\mathbf{v}_1) + \cdots + c_p T(\mathbf{v}_p) = \mathbf{0}$$ Since $T$ is linear: $$c_1 T(\mathbf{v}_1) + \cdots + c_p T(\mathbf{v}_p) = T(c_1\mathbf{v}_1) + \cdots + T(c_p \mathbf{v}_p)=T(c_1 \mathbf{v}_1 +\cdots + c_p \mathbf{v}_p)=\mathbf{0}$$ So the set $\{\mathbf{v}_1, \dots , \mathbf{v}_p \}$ must be linearly dependent. Am I missing something? And why must $T$ be on-to-one for this to be true? An example showing that it is not true if $T$ is not one-to-one would be great!


I'm writing my master thesis. I need to quote a cited quote from another paper. So the scenario is that I'm reading a paper and this paper has a quote which is cited from another paper. Now I want to quote this quote, how should I cite this?  Is it correct to just write the text of the quote and then cite the paper I'm reading? Or should I cite the original paper? The thing is that if I cite the original paper then I will be considered that I read that paper, however i don't want to read that paper. So what is the correct thing to do here?


Infinitely many $n$ such that $2^n-n$ is divisible by a prime

I found the following question and can't make much headway with it.  Show that there exist infinitely many positive integers $n$ such that $2^n \equiv n \mod p$ where $p$ is a odd prime...  I started by writing the number as $n=(p-1)k+c$ which implies $$2^c \equiv c-k \mod p$$ where I used Fermat's Little theorem. Now if $k$ is of the form $pm$ for some integer $m$ we get $n=(p-1)(p)m+c$   $$2^c \equiv c \mod p$$ and we have reduced $n$ to some smaller integer $c$ but I can't figure out how to find the smallest number $c$ which would then generate infinitely many $n$.  Any help in finding a possible approach to this would be highly appreciated.


Avengers, Fantastic Four and Guardians of the Galaxy Timeline

Are '', '' and '' movies set in the same timeline?


I want to build a health bar which show's the energy of the player.I have two buttons "PLAY" and "IDLE" to show the animation.when I click on the "PLAY" button the character start running along with that the health bar should decreases it's energy.Here is the code written for the two button clicks  void OnGUI() {             if (GUI.Button (new Rect (100, 200, 50, 50), "PlAY")) {                     animation.Play ("run");             }     if (GUI.Button (new Rect (100, 500, 50, 50), "IDLE")) {         animation.Play ("idle");     }     }   Now I need to create a health bar to show the decreasing of energy when the player starts its animation.Could you please help me in coding out creating energy bar.    Done the code for creating the progress bar,but the bar is not getting decremented.Here is the code  private float loadBarProgress = 0.0f; private const float loadBarSpeed = 0.25f; public Texture loadBarTexture = null; void OnGUI() {     //Draw loading bar with offset texture coordinates     GUI.DrawTextureWithTexCoords(new Rect(Screen.width * 0.4f, Screen.height * 0.4f, Screen.width * 0.2f, Screen.height * 0.1f), loadBarTexture, new Rect(loadBarProgress, 0.0f, 1.0f, 1.0f), false); } // Use this for initialization void Start () {  }  // Update is called once per frame void Update () {     //Move the bar along; keep it's position between zero and one for best float point precision     loadBarProgress += Time.deltaTime * loadBarSpeed;     if (loadBarProgress >= 1.0f) loadBarProgress -= 1.0f; }


Why does my spellcheck disallow themself, but not themselves?

When I type "themself" my computer browser spellchecker underlines it in red. It's an error.  When I right click the word I'm offered 3 alternatives "them self", "them-self", and "themselves".  Why is "themselves" correct but "themself" wrong?


Why must $A(V)$ be an open subset of $A$'s range?

Suppose $A$ is a linear transformation from $\Bbb R^n$ to $\Bbb R^m$ with $\text{rank}A=r>0$, $V$ is an open subset of $\Bbb R^n$, then is $A(V)$ an open (relative to $\text{Im}(A)$) subset of $\text{Im} (A)$?  I don't know how to prove this. I cannot construct a diffeomorphism from $V$ to $A(V)$ because there is a dimension shrinkage.   Can you help me with this? Thanks a lot!


What does | symbol near end of a command do?

I came across someone using the command zcat [filename].gz | less to open a file. What does | generally do when it's using in this manner? I've tried googling the question but haven't found the answer yet.  EDIT: actually the answer is here:


Series involving Intergalactic performance art

This is a series of books about an interstellar human civilization. After losing a few colonies to unknown reasons, Humanity comes across these rogue asteroids traveling through space. They are made up of two parts traveling at slightly different speeds. In time when they catch up to each other, there is a huge explosion. By third or fourth book the protagonist figures out this is just some kind of fireworks display setup by aliens.   I remember it having a 70s/80s feel when I read it.


Can't trigger 5V,10A relay using the output from a ESP8266 node MCU?

I'm currently working on a project where I turn off the ac appliances when the input signals of the relay get high. I'm using a 5V 10A relay and ESP8266 node MCU. But the problem is controller is unable to switch the relay. What should I do? Please help.


I have a model, with a node setup that includes a texture. The problem is that the texture isn't showing. How it should look (the little spot distortions are visible):  How it looks:  My node setup Node Setup  The file can be downloaded here:


Will university admissions google the academics who write my references?

I'm applying for masters. Will those reading my applications actually bother looking up the people that wrote my references?   I'm considering whether I should ask prestigious academics (who don't know me well) write my references vs not-so-prestigious ones (who know me). Obviously if they wont google the names, I should go with the latter.


Moto g 2 Battery is draining within 3 hours

My motog 2 is draining the battery drastically as fast as it can. Please help me. I couldn't carry a charger all the tym. I have consulted the customer care service they provided me two links to reboot and reset the settings. But it doesn't works. Help me thank you.


How to take command arguments from a file, one per line?

Say I have a file of filenames like this: requests.log responses.log resources used.log  and I want to view all of those files. I'd be tempted to do: $ vi `cat /tmp/list`  but that winds up opening the files "requests.log", "responses.log", "resources", and "used.log" which is not what I want. I tried $ cat /tmp/list | xargs -L 99 vi  but that results in the error message "Warning: input not from a terminal" I've tried editing the file and quoting each of the individual lines, but that was no help either. Is there a way to do this short of writing some sort of front-end script?


How does orienting a cube-shaped spell work in three-dimensional space?

Can the caster orient the cube any way they like? Can the point of origin effectively be a corner, with the opposite corner pointing any way the caster chooses?  This question was tagged as a duplicate; however, the linked question and its answers presuppose that the cube has a face parallel to the ground. In that question, the "cube" is effectively a square on the ground, plus L feet of airspace above the square (where L is the length of a side of the square).  This question challenges that assumption. I read the rules, and I took them to mean that a cube-shaped spell was an invitation for creative use of three-dimensional geometry.   I get that some groups will ignore or fail to notice this invitation (not every group will enjoy geeking out over geometry). My question, though, is whether this creativity is actually prohibited by the rules. Is there a rules-based argument to prevent, for example,a cube-shaped spell from hitting a target R + L*sqrt(3) feet away, where R is the spell's listed range and L is the listed length of the cube's side?  The description of a cubic area of effect is given as follows (PHB. 204, or here in the )     CUBE       You select a cube's point of origin, which lies anywhere on a   face of the cubic effect. The cube's size is expressed as the length   of each side.      A cube's point of origin is not included in the cube's area of effect,   unless you decide otherwise.   Can the cube's point of origin be at the corner or edge of the cube-- or at least arbitrarily close to the corner or edge of the cube? Even if we parse "face" as "not including edges or corners," surely the caster can declare that the point of origin is a picometer from the edge or corner?  Can the caster orient the cube at funny angles? I don't see any rule saying the cube can or can't have whatever orientation the caster likes.  Take  (PHB p. 282) as an example:     A wave of thunderous force sweeps out from you. Each creature in a   15-foot cube originating from you must make a Constitution saving   throw. On a failed save, [things happen].   How close does a caster have to get to a single target to hit them with thunderwave? The way I figure it, a caster can set one corner of the cube as the point of origin, then orient the opposite corner in the direction of the intended target.   If I did the math right, the distance across the diagonal of a cube is L*sqrt(3), where L is the length of a side of the cube. Hence, thunderwave could hit a creature as far as 25.98 ft from the caster (because 15ft * sqrt(3) is approximately 25.98 ft).   This would cause part of the spell's Area of Effect (actually, it's a volume) to be blocked by the ground.


One vs someone, can be used interchangeably?

I've been searching about the ability to use "one" and "someone" interchangeably but found almost nothing. So what's the difference between them and can they be used interchangeably, for example, in these sentences:   There are numerous things (one, someone) could notice There is a hidden place (one, someone) might find  If (one, someone) comes up to you and asks....


Break one line of "if else" statement into multiple lines

I want to break this code:  ex = func(object) if not self.is_object() else foo()   to multiple lines (pep 8). What is the best way to do it? I thought about this:  ex = func(object) \     if not self.is_object() \     else foo()   But this seems a bit ugly and not very neat. Is there another way?  Edit: This is different from just breaking a line into multiple lines, because this is a special "expression if stmnt else stmnt" and not just breaking any python code.


Automatic text for labeling lemmas, examples etc

If I label an equation I use   \label{bla} \eqref{bla}   since then it automaticalls copies the number of the equation e.g. 1.1 and with \eqref{bla} I get (1.1) with the link to the equation - perfect... However, I defined many other things like "Lemma", "Remark", "Example", Theorem" etc. Now is there something like eqref that automatically checks the title, e.g. Lemma 1.2 and then writes "Lemma 1.2" with the link to it similar to eqref?  Or do I need to define it? If yes- how could I do it?


Fantasy novel with female protagonist and mages who can be drained of power by a cut?

I believe it was a standalone, but possibly 2 books. The main character was a female. The mages in the story exploded when they died unless they were completely drained of power first.  They could be drained by making a small cut and then the other mage touching the cut and draining them (to the extent it would kill them). A large portion of the book was main character's training to use magic at a school where thy would basically put up magical shields and duel each other. I believe I read it in late 90's to early 2000.


Custom ArrayAdapter NPE: Attempt to invoke TextView on a null object

So, I'm writing this nifty custom adapter for a listView that should display profile info. Everything works well - I successfully pull out info from database, put it into ArrayList and achieve something like this in the MainActivity:  ProfileListAdapter adapter = new ProfileListAdapter(activity, R.layout.existing_profile_menu, profiles); listView.setAdapter(adapter);   For ProfileListAdapter I use:  public class ProfileListAdapter extends ArrayAdapter<ArrayList<String>> {     private Context context;     private ArrayList<ArrayList<String>> values;     private int layoutId;      public ProfileListAdapter(Context context, int resource, ArrayList<ArrayList<String>> values)     {         super(context, R.layout.existing_profile_menu, values);         this.context = context;         this.layoutId = resource;         this.values = values;     }      @Override     public View getView(int position,View convertView,ViewGroup parent)     {         LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);         View rowView = inflater.inflate(R.layout.existing_profile_menu, parent, false);          TextView mainTitle = (TextView)rowView.findViewById(R.id.mainLine);         TextView subTitle = (TextView)rowView.findViewById(R.id.subLine);          mainTitle.setText(values.get(position).get(1) + " " + values.get(position).get(2));         subTitle.setText(values.get(position).get(6) + " " + values.get(position).get(3));          return rowView;     }  }   What I get as an error is:  java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference  And I'm pretty sure that it's somewhere at this section:  LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);         View rowView = inflater.inflate(R.layout.existing_profile_menu, parent, false);   I looked around similar sounding questions here, but couldn't find anything that would budge my case.  [UPDATE]  Issue resolved. Make sure that views are located in the layout you're using for the adapter. Or that you didn't mess up with layout naming.


Minor clerical error- tier 5 mobility visa

I just finished my application, and thought I checked it over pretty well  submitted, and printed.   I just did another check to realize I entered my mother's year of birth wrong. It's certainly not 2017. Lol   How shall I proceed? Is it advisable to correct neatly with pen, straight line through? Perhaps include a cover letter just stating my clerical mistake? Do I just mention this to the ECO?   My appointment is in three days... Help!


the number of ways in which $5$ men and $7$ women can stand in a queue such that exactly 6 women stand consecutively

Let $n$ be the number of ways in which $5$ men and $7$ women can stand in a queue such that all the  women stand consecutively. Let $m$ be the number of ways in which the same 12 persons can stand in a queue such that exactly 6 women stand consecutively. Then the value of $\frac mn$ is (A) 5 (B) 7 (C) $\frac 57$ (D) $\frac 75$ Try Considering the $7$ women as a unit the $5$ men and the unit can be arranged in $6!$ ways. In each arrangement the $7$ women can arrange themselves in $7!$ ways. So total arrangements $n=7!\times 6!$. But I'm stucked in the second part. Please help to understand the underlying counting technique. Thanks in advance.


I have just (painfully) upgraded to Ubuntu 18.04 LTS.  Since it appears I have no choice but to use the GNOME desktop, I am trying to make adjustments so that I can use it more like the Unity desktop I used in 14.04 and 16.40.  But I find I can make no changes to the size and position of the Dock.  When I go to Settings and click on Dock, the only thing visible in the large right-hand panel is a very faint slider bar, with no slider.  Positioning the cursor over this bar has no impact.  In short, on my system the Dock is completely unadjustable.  What I was expecting was something like this:  . I.e., the ability to adjust the size, position and auto-hiding capability of the Dock.  What do I have to do to make the Dock adjustable?    $ apt-cache policy gnome-shell-extension-ubuntu-dock gnome-shell-extension-ubuntu-dock:  Installed: (none)  Candidate: 0.9.1ubuntu18.04.1  Version table:    0.9.1ubuntu18.04.1 990      990 http://us.archive.ubuntu.com/ubuntu bionic-updates/main amd64 Packages      990 http://us.archive.ubuntu.com/ubuntu bionic-updates/main i386 Packages     0.9.1 990      990 http://us.archive.ubuntu.com/ubuntu bionic/main amd64 Packages      990 http://us.archive.ubuntu.com/ubuntu bionic/main i386 Packages


I was able to solve this equation using graphical methods, but cannot figure out a mathematical solution to the equation.  What approach should be taken to solve it?


I am into finding a convincing formula, or at least a rule of thumb, about when to use "to" and when to use "for" after adjectives - such as easy, difficult, important, interesting, and useful - and before personal pronouns and nouns.  I have gone through numerous and different advice by English-speaking people on the "to vs. for" problem for non-English speakers.  There were some cases in which they seemed interchangeable while there were others where they did not. Many people said the issue could be more about a preference or tendency than a rule, thus leaving English learners no choice but to learn them case by case. I came across some advisers who came up with a few rules, some of which I found very helpful while others seemed to contradict one another.   In the following examples, "to" and "for" seem to be interchangeable, and yet slightly different in meaning.   I reason that a marked difference between "to me" and "for me" would be found in whether "me", the narrator, has experienced it, the subject of the sentence, or not.   (A) English is not easy "to me".   This implies that English is not easy "in my view (in the view of the narrator)".  (B) English is not easy "for me".   This implies that English is not easy "in my experience (in the experience of the narrator)".  How does my reasoning sound to you? Any comments will be greatly appreciated.


Is the Universe being dragged into a singularity rather than expanding?

Recently I've read that  as proposed by Hubble. Therefore is it possible that instead of space expanding in all directions all matter is falling toward some distant barycentre? Galaxies already closer to it than our own would be accelerating faster and thus we'd observe them redshift. At the same time, our galaxy would be accelerating faster than galaxies which are farther away than us from the "universal centre of mass" which should also result in observing them move away from us. Assuming we have only seen a small part of Universe and in particular only space on one side of the supposed centre so far, all galaxies except the ones on the same sphere around the distant centre as ours would look redshifted to us. For example when looking at  one can see a big purple arc which could be due to galaxies having the same distance as we do from the centre.


I want to add class to some div's when I hit the same button second time

I am removing the btn class after I hit it for the first time and adding new class to it. When I hit second time with btn1 class it's not adding any class.  <script type="text/javascript"> $('.btn').click(function(){     $('.fC').addClass('fCr');     $('.sC').addClass('sCr');     $('.btn').addClass('btn1').removeClass('btn'); }); $('.btn1').click(function(){     $('.tC').addClass('tCr');     $('.sC').addClass('fCr'); }); </script>


How to stop Google Chrome taking over Internet Explorer?

I have been using Google Chrome for years.  Loved it, up until recently.      I had Adblock installed but ads were coming through and disrupting my work.      Then Adblock just disappeared from the extensions list.    I couldn't print emails, it just locked up.    I went to use Internet Explorer to get some work done and it loaded as Google Chrome.   I eventually recovered my computer back to a previous date, uninstalled Google Chrome, and went to use IE.  After a few minutes of being in IE, it shut down on it's own.    I clicked on the IE icon and it came up as Google Chrome.    I went back in and uninstalled GC and now I don't have IE.   I ran the malware program but says it can't find anything.    Now I have Firefox and hope it doesn't have the same thing happen.    What could have gone wrong and how can i get google chrome, IE working agian? Thank-you for any help


Why is it better to use "#!/usr/bin/env NAME" instead of "#!/path/to/NAME" as my shebang?

I notice that some scripts which I have acquired from others have the shebang #!/path/to/NAME while others (using the same tool, NAME) have the shebang #!/usr/bin/env NAME.  Both seem to work properly.  In tutorials (on Python, for example), there seems to be a suggestion that the latter shebang is better.  But, I don't quite understand why this is so.  I realize that, in order to use the latter shebang, NAME must be in the PATH whereas the first shebang does not have this restriction.  Also, it appears (to me) that the first would be the better shebang, since it specifies precisely where NAME is located.  So, in this case, if there are multiple versions of NAME (e.g., /usr/bin/NAME, /usr/local/bin/NAME), the first case specifies which to use.  My question is why is the first shebang preferred to the second one?


Choosing finite field size in Shamir's Secret Sharing Scheme

The Wikipedia article on Shamir's Secret Sharing says to that to have information theoretical security the splitting algorithm should be evaluated using finite field arithmetic on the field $\rm{GF}(p)$ such that $p>n,p>S$ where $n$ is the number of shares and $S$ is the information to be shared. It suggests that on the one hand $p$ should be large because an attacker knows that $S\in\mathbb{Z}/p\mathbb{Z}$. It also suggests that $p$ should not be too large because an attacker knows that as $p\uparrow$ $\rm{p}\{f(x)\bmod p = f(x)\}\uparrow$. How should one choose the best value of $p$ and be confident about choice?   implementation splits $S$ into $i$ pieces such that $\forall \,i,\,S_i\in\rm{GF}(257)$. I do not understand a specific reason to use $p=257$ over any other prime number. For instance the elements $S_i$ could be stored in in an 8 bit value if $p=251$ was chosen.


Given $ax^2+by^2+cxy > 0$, what can I deduce about $a$, $b$, and $c$?

I know that for any nonzero $x,y\in\mathbf{R}$,  $$ax^2+by^2+cxy > 0,$$  where $a,b,c\in\mathbf{R}$. What can I deduce about $a$, $b$, and $c$?    For example, letting $x=1$ and $y=0$, I know that $\boxed{a>0}$. Letting $x=0$ and $y=1$, I know that $\boxed{b>0}$. Letting $x=y=1$, I know that $\boxed{c>-(a+b)}$.  What else can I deduce about $a$, $b$, and $c$? How will I know when it's time to stop looking? (Is that last question even answerable?)


Intersection of normal subgroups is normal

Can someone tell me if this proof is sufficient given the assumption.  Let H,K be normal subgroups of G. Assumption: g(H∩K)= (gH)∩(gK)  Proof: g(H∩K)        =(gH)∩(gK)        =(Hg)∩(Kg)        =(H∩K)g  Can someone tell me if I am missing something? I haven't seen this solution before and it seems simple.


What is the name for the grammatical device of putting "not" after a verb to negate it?

Here's a passage (more or less taken randomly) from the  of the Bible from 1901:      (ASV)   14 But even if ye should suffer for righteousness' sake, blessed are ye: and fear not their fear, neither be troubled;   The bolded words are the grammatical form I'm asking about.  It's extremely common in the older translations of the Bible, which make them difficult to read.  These days, I think most people would say "do not fear their fear" of "don't be afraid of their fear" instead.  In fact, a  reads:      (NASB)   14 But even if you should suffer for the sake of righteousness, you are blessed. And do not fear their intimidation, and do not be troubled,   (There's a footnote on"intimidation" saying "Lit fear", so my first update matches exactly.)  Reading up on  I haven't been able to discover a name for this word ordering or any history about the change.  Can y'all give me some pointers?    I'm not sure if this part of the question is on-topic, but when I find this form would I be safe in mechanically changing it from:     verb not   to      do not verb   Are there instances that will break the meaning by doing this?


SLDS icon not appearing in visualforce page

Script 1: Does not Work  <apex:page >     <apex:stylesheet value="{!URLFOR($Resource.slds221, 'assets/styles/salesforce-lightning-design-system.min.css')}"/>     <svg aria-hidden="true" class="slds-icon slds-icon--x-small slds-icon-text-default slds-is-sortable__icon">         <use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="{!URLFOR($Resource.slds221, 'assets/icons/utility-sprite/svg/symbols.svg#email')}"></use>     </svg> </apex:page>   I can't see any icon on my page. However when I remove stylesheet reference it renders fine. What am I missing  Script 2: This Works (Removed slds-static reference)  <apex:page >     <svg aria-hidden="true" class="slds-icon slds-icon--x-small slds-icon-text-default slds-is-sortable__icon">         <use xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="{!URLFOR($Resource.slds221, 'assets/icons/utility-sprite/svg/symbols.svg#email')}"></use>     </svg> </apex:page>


I am building a Human Gunslinger character who uses the Racial Heritage feat to get access to the Goblin Gunslinger feat so he can use a large double hack-but without penalty. Problem is, the the table for converting the damage for weapons sized for medium creatures to damage for weapons sized for large creatures stops at 2d10 and the medium double hack-but does 2d12. What damage would a large double hack-but do?


How do I make a normal/displacement map when all I have is a photo?

In order to make a rendering look more realistic some additional maps are useful.  The  lists: diffuse,specular displacement-maps .  I watched a video  which uses a commercial tool.   Are there any alternatives to calculate normal and displacement maps from an image texture, or can this also be achieved by some build-in transformations?  NOTE: As requested, this is related to image-textures that have been downloaded from a site like  which are image-only and lack of normal- and displacement-maps.


Have a web-part display only sub-folders?

I am new to SharePoint 2013. I was curious how to put a WebPart for a Document Library on a page with SharePoint 2013, not 2010.   This WebPart would then show the content of a specific library folder and not start at the root of the folder. So say I have a library with multiple folders like "Marketing", "Finance" etc,   I want to be able to create a web part that would only show the contents within the “Marketing subfolder and all of it contents. Is this possible?


Prove the non-existence of any triplet satisfying $\frac{x}{y}+\frac{y}{z}+\frac{z}{x}=1$

Prove that there do not exist any positive integers $x,y$ and $z$ that satisfy $\frac{x}{y}+\frac{y}{z}+\frac{z}{x}=1$   My attempt:-     Since $x,y $ and $z$ are positive integers, we can assume without loss of generality that $x\le y\le z$  . Hence we have  $\frac{z}{y}$ and $\frac{y}{x} \ge 1$. This implies, $$\frac{x}{y}+\frac{y}{z}+\frac{z}{x}\gt 2$$. Therefore, there do not exist any integers $x,y $ and $z$ satisfying the above equation. Does this look good? Can this be solved using divisibility or any other technique ?


I'm trying to write the prime factorisation of 60 in latex. Using underline and vertical bar, I was able to create something similar to what I intended. Is there a better way to do so? $5| \underline{60}$         $3| \underline{12}$               $2| \underline{4}$                                               $\color{white}{--}2$


Cutting hole in raster using polygon in ArcGIS Desktop?

I have two layers: a layer with a raster and a layer with a polygon, I need to cut a polygon from a layer with a raster, how to do it?  It is necessary to make a straight hole, and not to create a new layer not true:    just like this:


I am using apex data table in apex outputpanel. I want to make the header fixed on scrolling. But I am not able to get the result. Here is my code :  <apex:outputPanel styleClass="dataTable" id="tbid">
CA&amp;S Sales Support Proposals

  <apex:datatable value="{!usspt1}" var="Opp" html-cid="accountsTable" id="contacttable" styleclass="display" columnsWidth="1%,1%,4%,3%,3%,4%,2%,2%,2%,2%,2%,2%,2%,2%,2%,3%,3%,28%,19%,3%" >                      <apex:column headerValue="STS Lead" >                <apex:outputfield value="{!Opp.STS_Lead__r.Name}" />              </apex:column>             <apex:column headerValue="High Level Summary" >                    <apex:outputText value="{!left(Opp.High_Level_Summary__c,500)}"   />             </apex:column>                  <apex:column headerValue="Critical Next Step" >                 <apex:outputText value="{!left(Opp.Critical_Next_Step__c,500)}"   />            </apex:column>                    <apex:column headerValue="Key Dates" >                <apex:outputfield value="{!Opp.Key_Dates__c}" />              </apex:column>         Here is my CSS which using for table header.  .dataTable  th{ background: #305492; border-top: solid 1px #E0E3E5; border-right: solid 1px #E0E3E5; color: #fff; font-size: 1.15em; font-weight: normal; padding: 11px 2px 10px 5px; white-space: normal; }


How do I destroy the "red blocks" in dungeons in Terraria

I use the app version and this "red block" (I don't know why it's called that) but it's in the dungeons with the Blood Crawlers and Hearts, and it won't break.  How can I break the "red block?"


Is the subset $\mathbb{Q}[\sqrt2]:=\{x+\sqrt{2}y\mid x,y\in\mathbb{Q}\}$ of $\mathbb{R}$ a field?

Consider the subset $\mathbb{Q}[\sqrt2]:=\{x+\sqrt{2}y\mid x,y\in\mathbb{Q}\}$ of $\mathbb{R}$, together with the addition and multiplication usual/common in $\mathbb{R}$      (Does this mean that the operations $(+)$ and $(\cdot)$ are from $\mathbb{R}$ ?).   Is $\mathbb{Q}$ a field? Prove your testimony.  If you want to find a neutral element $e$ for multiplication, such that $e\circ x=x$, you will get stuck:  \begin{align} e\circ x&=x\\ (x+y\sqrt2)\cdot(z+w\sqrt2)&=z+w\sqrt2\\ e=(x+y\sqrt2)&=1\qquad\qquad \forall x\neq0 \end{align}  If you want to find an inverse element for multiplication $a^{-1}$ such that $a\circ a^{-1}=e$, you will get stuck: \begin{align} (a+\sqrt2b)\cdot a^{-1}&=1\\ a^{-1}&=\frac{1}{a+b\sqrt2} \qquad\qquad\forall a\neq0 \end{align} Is this the point where I can say, that $\mathbb{Q}[\sqrt2]$ is not a field, because you can't find a neutral and inverse element for all elements in $\mathbb{Q}$?


True or False: there is a space $X$ such that $S^1$ is homeomorphic to $X\times X$

I had an exam this morning, one of the questions asked about the truth of the statement      There is a space $X$ such that $S^1$ is homeomorphic to $X\times X$.   I said that this was false and this was my reasoning... was I correct? (Note, an earlier part of the question asked me to prove $\pi_1(Y\times Z)=\pi_1(Y)\times\pi_1(Z)$, I took this as a hint.)  Suppose for the sake of contradiction that such an $X$ exists. Then $\Bbb{Z}\cong G\times G$ where $G\cong\pi_1(X)$. Let $\Phi$ be the isomorphism.  Let $\Phi(1)=(g_1,g_2)\in G\times G$. Then at least one of $g_1,g_2$ is nonzero, since $\Phi(0)=(0,0)$ (the identity on $G\times G$, and $\Phi$ is injective). Without loss of generality $g_1\ne 0$. Then which element $n\in\Bbb{Z}$ has $\Phi(n)=(kg_1,0)$? Since $$kg_1=\underbrace{g_1+\dots +g_1}_k\in G,$$ and $\Phi$ is surjective, such an $n$ should exist. But this is not possible since $\Phi(n)=(kg_1,0)$ implies (since $\Phi$ is a homomorphism) that $kg_1=ng_1$ and $ng_2=0$, and since $k$ was arbitrary and this need not hold if $k\ne 0$.


I installed TrueCrypt from their website (.tar.gz file) extracted through the archive manager to /usr/share/truecrypt. I no longer need the app but I cannot uninstall it through  sudo apt-get remove   I get an error message:  'virtual packages like truecrypt cannot be removed'.    All of the sub-directories and files in /usr/share/truecrypt have a padlock symbol on them.  I don't know how to remove unwanted apps beyond these basics, I'm hoping you can help. I have a small(memory),  elderly Toshiba Satelite laptop so it doesn't need to carry any baggage.  Thanks,  David


In website have many AUTHENTICATED USER. I want to how many times spent of each user on site.  I use login history module, it show only every login time of all user.   I use time spent module, but not track all time of every page.  Please suggest how to calculate time spent of each user on every login.


Are you supposed to stir sauerkraut while it is fermenting?

I am making sauerkraut I have the cabbage and salt in the crock. I mixed it together really well as I did this.  I know it takes several days to be ready to can. Do I stir it some more while it is fermenting?


How do you determine native american ancestry?

How would you determine how much cherokee indian in your heritage is your great great grandmother was 1/2 cherokee indian?


Doesn't light have to be a wave since it has a wave length? (In contrast to the wave–particle duality)

We learned in school that photons behave partly like a wave and partly like a particle, so they can be both at the same time. We also learned that light consists of alternating electric and magnetic fields that travel through empty space as seen in the picture below. So if you can always name the specific wave length of a quantum object, doesn't that necessarily imply that this object must be a wave?


travel insurance only for missed or canceled flights

I am traveling to Indonesia the next month and I am told that flights are often delayed or canceled. Therefore one can easily miss a connection or miss the first (already paid) night in some hotel.  I already have a medical insurance for when traveling and I am even insured for lost luggage. The only thing I am missing is an insurance that covers flights issues. Is there such an insurance? Can you recommend any?