Find a function that makes this differential form exact

We have $\Omega=\mathbb{R^3}\backslash \left\{ (0,0,z):z\in \mathbb{R}\right\}$ and $\omega$ the differential form: $$\omega :=\left(\frac{4x^2+2zx}{x^2+y^2}+2A(x,y)\right)dx+\left(\frac{2y}{x^2+y^2}(2x+z)\right)dy+A(x,y)\,dz,$$ where $A\in C^1(\mathbb{R^2}\backslash(0,0); \mathbb{R})$  Find a function $A$ that makes the differential form exact.  My teacher advised to use the homotopy of the curves of which I make the integral. Namely find two curves on which the integral is $0$, one that surrounds the origin and the other doesn't, and hence obtaining all the other curves through continuous deformation. For the curves that don't include the $z$-axis I can just take a ball that contains the curve, and since the ball is convex, I know that a closed differential form in a open convex set is exact (I'm pretty sure it is closed). I'm stuck on the curves that surround the $z$-axis, any ideas?


I am trying to create points (new layer) at specific distance along the road (existing layer) in QGIS.   gives solution for ArcGIS. How to achieve this in QGIS?  explains how to create points but does not do anything about the distance.     (I applied the proposed solutions with different measures of lengths for I did not know the conversion) @Nathans's solution worked to some extent, I got...  . Here, the projection of these equidistant points is different from the original line.  With @underdark's suggestion, I got   where the points does not seem to be equidistant. I guess there is some projection issue with both of these which I am not understanding.


Box plot for Likert scale 1 to 5: How is maximum equal to upper quartile?

I need to know how to interpret each of the graphics.


Site-Recommendation for "What is the longest-running endless loop?"

Which site does this question belong on?  It is my contention that any and every endless loop is going to end rather sooner than later. Just for curiosity: "What is currently the longest-running known implementation of an endless loop?"  I'm in search for a technical device with an active program running an endless loop. It needs to be a known technical implementation within this universe, not some hypothetical machine / idea or abstract concept.


Create small package combining SO answers?

I'd like to combine 2-3 existing SO answers (and add an icon and .desktop etc.) to create a small, but useful open-source (Debian) package. I can license everything under "CC-by-SA 3.0", which is the Stackexchange standard license for contributions AFAICT. However how do I go about copyright attribution? Do I have to track down the authors of the answers?  Is this possible or are stackoverflow answers essentially un-reusable in public-facing code? I suppose I could rewrite the code in question, but I don't feel this would be a productive use of anyone's time.


What is the expectation of copula function?

Let's say $X=(X_1,X_2)'$, where $X\in \mathbb{R}^2$. What is the expectation of the copula function $C(F_{X_1}(x_1),F_{X_2}(x_2))$ - i.e. $\mathbb{E}_X\left[C(F_{X_1}(x_1),F_{X_2}(x_2))\right]$?


Simple addition exposes Javascript engine floating point error

While working on , the joys of TDD helped me stumble upon a really strange (at least as i occurs to me) behaviour exposed in the javascript engines.  No matter if entered into the console or performed inside a script, this is what happens:  -1 + 0.85     --> -0.85               ✓   -1 + 1        --> 0                   ✓    -1 + 1 + -.15 --> 0.15                ✓ -1 + 1.15     --> 0.1499999999999999  ?!?   This is tested and reproduced exactly under following Browsers / OS's:   FF 24.0 (Debian 3.10)  Chrome 30.0.1599.114 (Debian 3.10)  Chrome 30.0.1599.101m (Win7SP1) Internet Explorer 10.0.9200.16721 (Win7SP1)   As this is consistent throughout different vendors, i assume there must be a specific reason for this, so:   What is the reason for this? What is the best practice to circumvent this behaviour, as it poses a problem for exact calculations with JS     Update: Best lay-comprehensible explanation incl. answers and workarounds for multiple programming languages so far found at   (thanx @RocketHazmat)


How can I trigger a command when a player is hit by a Snowball?

I am trying to make a snowball that triggers a command when it hits a player in 1.15, but I don't know how to do that. When I do execute at @e[type=snowball] run gamemode spectator @a[distance=..2] it only runs the command if it goes right next to them.


I've started to write a brainfuck compiler in bash. The 'compiler' translates the code in assambly to compile it using gcc. The problem is, when I try to run it, it prints this error:  $ ./compiler test.bf ./compiler: Zeile 111: src: {0..45}: Syntax Fehler: Operator erwartet. (Fehlerverursachendes Zeichen ist \"{0..45}\").   (In english:  $ ./compiler test.bf ./compiler: Line 111: src: {0..45}: Syntax Error: Operator excepted. (Causal Error Char is \"{0..45}\").   )  As I might understand, It says that there is a fault in line 111:  ... for i in {0..${#src}}        # line 109 do                           # line 110     case ${src:$i:1} in      # line 111 ...   (Here is the full )  But I don't see any.  If the error is cause of the for loop, can you tell me how to make a for loop like in python:  for i in range(15):     ...   Thanks in advance


Problem on the number of generators of some ideals in $k[x,y,z]$

I have got stuck with two generator problems:        The ideal $(zx,xy,yz)$ can't be generated by $2$ elements.    The ideal $(xz-y^2,yz-x^3,z^2-xy)$ can't be generated by $2$ elements.      Here the ring is $k[x,y,z]$.  Thanks in advance for any help.


Should there be a comma before a person's name midsentence when you're addressing them?

Take the following sentence I found myself typing in an email today:     Thanks for the update, Mark, good to hear.   That first comma had me hesitating for an embarrassing length of time. Consider the alternative:     Thanks for the update Mark, good to hear.   Honestly both look strange to me now that I'm overthinking it. Is there a rule I can defer to so I can make this easy and stop thinking about it?


This is a basic notation question. With trig functions like $\sin{x}$ and $\cos{x}$, if they are raised to a power, let's say $a$, then we write it, in the case of $\sin{x}$, as $\sin^a{x}$. However, with regards to logarithms, I've been wondering if the notation is the same; is $(\ln{x})^a$ written as $\ln^a{x}$? That'd simplify and clarify some working significantly. Thank you for your help in this trivial matter.


Inserting a string 'india's' into a sql database

I have a table xyz(name varchar(200)) i wanted to insert names such as 1.ramu's 2.shyam's when i try to insert using insert as it is throwing an error   quoted string not properly terminated   insert into  xyz values('ramu's');


Is it acceptable to write the nonce to the encrypted file during AES-256 GCM?

I've used AES-128 in CTR mode in the past and using the same key but different IVs for each file, I wrote the IV to the first 16 bytes. Is it safe to do so with the nonces used in AES-256 GCM? I'm using the word nonce here because that's what is declared in the Sodium library.  Are the uses for IVs and nonces exactly the same?  Also, is there any use in providing additional authenticated data? Should I keep it NULL?


Will a can filled with vacuum move when we let in air?

This picture is from L.C.Epstein's book Thinking Physics. The upper can is filled with compressed air, and, when an opening is made on the right, the air comes out and the can shoots left. The question is what happens to the lower can, filled with vacuum, when we similarly make an opening. Does it move left - right - not at all?  Epstein says that the lower can doesn't move at all, "except for a momentarily slight oscillation about the center of mass". I'm not sure I understand this. The explanation is that the air incoming into the bottle provides force on the left inner wall to compensate for the lack of force on the opening, and this balances the force on the left outer wall from the outer air. Which seems convincing, but opens a path to more questions:   Shouldn't the can still start moving from the moment we make the opening and until the air pressure inside the can is equalized with the outside air? If that in fact happens, why would it stop and return ("a momentary slight oscillation about the center of mass") and not simply continue moving right with the constant velocity it's acquired?


writing to file gives me NullPointerException

I'm programming a code that writes an array of integers to a file. However, it keeps giving me a NullPointerException. Which I think is in one of two methods that I have, I know it's somewhere in there, but I can't spot it. Here's the code.  public static void WriteToFile (int[] n)throws IOException{     try{         BufferedWriter bw=new BufferedWriter(new FileWriter("C:\\sortfile2.txt"));         for(int i=0;i<=25;i++){             bw.write(sortArray(n)+" ");         }         bw.flush();         bw.close();     }     catch(IOException e){         System.out.println("Could not write to file");     } }   This is the first method that the error could be located in. The second is here:  public static int sortArray(int[] a){     int sort=0;     for(int i=0;i<a.length;i++){         int max=IndexOfMaxInRange(a,i,a.length-1);         sort=SwapElement(a,max,max++);         a[i]=sort;     }     return sort; }   Where IndexOfMaxInRange is a method that finds the highest integer of an array, and where SwapElement is a method that implements IndexOfMaxInRange, and swaps the highest number in the array, with the lowest.


How do you get a timestamp in JavaScript?

Something similar to Unix's timestamp, that is a single number that represents the current time and date. Either as a number or a string.


Why does my sizeof(arr) / sizeof(arr[0]) = 1?

typedef struct {   double *x;   int points; } Polygon;    polygon[cc].points = readobject(polygon[cc].file); //lets say equals 15 polygon[cc].x = (double *) malloc(polygon[cc].points * sizeof(double));  printf("%d\n", sizeof(polygon[cc].x) / sizeof(polygon[cc].x[0])); //This prints out on 1   I've test initializing x as x[100] and it works then, but shouldn't the malloc() call set the struct's array at x[15]? Is it just measuring the bytes of two doubles?


I have a tablet that runs Android Ice Cream Sandwich and would like to convert it to run Ubuntu as the Operating System. How easy is it to re install a tablet with Ubuntu?  The tablet is an Model N900   CPU Allwinner A13  FSB 1.5GHz  OS Android 4.0 ICS  Memory 512MB DDR3  Nandflash 8GB  Extended TF card; U disk, support TF card up to 32GB max  LCD Display 9 inch capacitive screen, 800*480  Internet Built-in Ethernet, support WIFI (802.11 a/b/g/n)  3G support external 3G module  Camera Front camera 0.3MP  I/O ports USB port, Headphone Jack, TF card slot  Touch Screen 5-point capacitive touch screen


If $cos(A-B)+cos(B-C)+cos(C-A)=\frac {-3}{2}$, prove that $cosA+cosB+cosC=sinA+sinB+sinC=0$

If $$cos(A-B)+cos(B-C)+cos(C-A)=\frac {-3}{2}$$ prove that $$cosA+cosB+cosC=sinA+sinB+sinC=0$$  My Attempt:  $$cos(A-B)+cos(B-C)+cos(C-A)=\frac {-3}{2}$$ $$cosA \cdot cosB+sinA \cdot sinB+cosB \cdot cosC+sinB  \cdot sinC+cosC \cdot cosA+sinC \cdot sinA=\frac {-3}{2}$$.  How should I go further? Please help me with a simple method.


Force periods in "Ph.D. thesis" in biblatex

Using biblatex and Biber, I want my bibliography to say "Ph.D. thesis" (with periods) rather than "PhD thesis" (without). MWE:  \documentclass{article} \usepackage{biblatex} \addbibresource{refs.bib} \begin{document} Hello \cite{testphd} \printbibliography \end{document}   and refs.bib:  @thesis{testphd,   title       = {Thesis Title},   author      = {Surname, Firstname},   date        = {2010},   institution = {Faculty of X, University of Y},   type        = {phdthesis},   location    = {Somewhere}, }   Output:    What's the easiest way to do this? I don't want to change the .bib file ideally.


Are there infinitely many primes such that...

Are there infinitely many primes $p$, such that,  $p-1=n^2$ where $n\in \mathbb{N}$.  As $p$ must be $odd$, we can say that $p$ must be of the form $4k+1$. But I do not know how to proceed.


What is the difference between "into" and "in" when cutting something

How can I explain the logical meaning of the difference between into and in when cutting something.  For example, 'Cut the peach into 3 pieces' vs 'Cut the peach in half'  Thank you!


How good are journal papers which ask you to pay x00$ to get published

I am looking to this journal -International Journal of Information and Education Technology and it seems they need 700$ to get my work included ,once it is approved.But is it a scammy journal .Has anybody heard of this practice before FYI ,here is the link


I read single variable calculus this semester, and the course is using Thomas Calculus as the textbook. But this book is just too huge, a single chapter contains 100 exercise questions! Now I'm looking for a concise and complete textbook. I'm not interested in routine, computational exercises, but rather some challenging problem sets.  I have quite a strong basic knowledge of calculus from high school, but I still have difficulties in solving a few questions from past exam papers. So I'm looking for more challenging exercises. In fact, I'm looking forward to solving Putnam level questions.  Please suggest some textbooks with these features. Thanks in advance.


Why is rm allowed to delete a file under ownership of a different user?

From the post  I understand that rm just needs write permission on directory to remove the file. But I find it hard to digest the behaviour where we can easily delete a file who owner and group different.  I tried the following  mtk : my username abc : created a new user  $ ls -l file -rw-rw-r-- 1 mtk mtk       0 Aug 31 15:40 file $ sudo chown abc file $ sudo chgrp abc file $ ls -l file -rw-rw-r-- 1 abc abc       0 Aug 31 15:40 file $ rm file $ ls -l file <deleted>   I was thinking this shouldn't have been allowed. A user should be able to delete only files under his ownership? Can someone shed light on why this is permitted? and what is the way to avoid this? I can think only restricting the write permission of the parent directory to dis-allow surprised deletes of file.


Proving $(x+y)^n = \sum\limits_{k=0}^n \binom{n}{k} x^k y^{n-k}$

I'm reading Serge Lang's 'Analysis I', and there's a problem I cannot figure out how to prove:     Problem: Prove by induction that $$(x+y)^n = \sum_{k=0}^n \begin{pmatrix} n \\ k \end{pmatrix} x^k y^{n-k} . $$   Attempt at proof : I established the base case, which is easily verified. Now I want to prove the inductive step. So assume the assertion holds for $n \geq 1$, and we want to show it also holds for $n + 1$. So we have to proof that: $$(x+y)^{n+1} = \sum_{k=0}^{n+1} \begin{pmatrix} n+1 \\ k \end{pmatrix} x^k y^{n+1-k} . $$ I started with the the LHS and applied the induction hypothesis: \begin{align*} (x+y)^{n+1} &= (x+y)^n (x+y) \\ & = \sum_{k=0}^n \begin{pmatrix} n \\ k \end{pmatrix} x^k y^{n-k} (x+y) \\ &= \sum_{k=0}^n \begin{pmatrix} n \\ k \end{pmatrix} x^{k+1} y^{n-k} + \sum_{k=0}^n  \begin{pmatrix} n \\ k \end{pmatrix} x^k y^{n-k+1} \\ &= \sum_{k=0}^n \begin{pmatrix} n \\ k \end{pmatrix} \bigg[ x^{k+1} y^{n-k} + x^k y^{n-k+1} \bigg] \end{align*} Now I don't know how to proceed. Any help would be appreciated!


Which musical piece is this from Code Geass?

This tune is from R2 episode 23, near 19:20 mark in the version I have, though it is played many times in the series.   The tune plays at 7:15 in this .  Does anyone know which musical piece this is?


How to dive into the PostgreSQL's optimizer and trace each step it takes to optimize the query?

Just like the MEMO structure in SQL Server which is kind of a "paper trail" of steps the optimizer takes in optimizing the query. Does PostgreSQL have the similar structure which records steps the optimizer takes?


I'm currently running a Windows 7 computer, but it says I have a 64-bit OS, and I'm confused as to whether or not I need to download the 32-bit version of Ubuntu, or the 64-bit, since it says to download the 64-bit version if I have a Windows 8 logo.


troubles proving $ \bigcup_{n\in\mathbb N}A_n = \bigcup_{n\in\mathbb N}\bigl(A_n\setminus\bigcup_{k=1}^{n-1} A_k\bigr)$ for sets $A_i$.

How can we show $$ \bigcup_{n\in\mathbb N}A_n = \bigcup_{n\in\mathbb N}\bigl(A_n\setminus\bigcup_{k=1}^{n-1} A_k\bigr)$$ for any family of sets?  So let $x\in \bigcup_{n\in\mathbb N}\bigl(A_n\setminus\bigcup_{k=1}^{n-1} A_k\bigr)=\bigcup_{n\in\mathbb N}\bigl(A_n\cap\bigcap_{k=1}^{n-1} A_k^c\bigr)$. So $\exists n: x\in A_n\cap\bigcap_{k=1}^{n-1} A_k^c $ and therefore $x\in A_n \wedge x\in A_1^c\wedge\dots\wedge x\in A_{n-1}^c   $. So we get $x\in \bigcup_{n\in\mathbb N}A_n.$   What happens if $A_i$ isn't pairwise disjoint? And how do you get the other way?


0% of the site has been indexed. There are 400 items left to index

Drupal core search doesn't re-index the site and it always shows this message.  0% of the site has been indexed. There are 453 items left to index.  What settings do I need to change to make Drupal re-index the site properly?


How can I add a directory to PATH in a script so that it affects the calling shell and the rest of the session?

I am new to Ubuntu.   I wrote a script to add a dir to the PATH environment. When I run the script it runs fine and the dir is added to the PATH. But it seems that the change only lasts until the script exits instead of lasting for the length of the session. When I look at the PATH after the script is ran the dir is no longer there. Any suggestions?


FilenameUtils.getExtension comparison returns false

I am very confused by this comparison with FilenameUtils.getExtension.  I have a file chooser fc that I want to ensure that the extension is .csv.   JFileChooser fc = new JFileChooser(); if (fc.showOpenDialog(null) == JFileChooser.APPROVE_OPTION &&     fc.getSelectedFile().isFile() &&     FilenameUtils.getExtension(fc.getSelectedFile().getName()) == "csv") {     // Do stuff }   After some debugging, I found that the last statement was responsible for not having the if statement executed.  FilenameUtils.getExtension(fc.getSelectedFile().getName()) == "csv"   However I did many System.out.println()s and got that  System.out.println(FilenameUtils.getExtension(fc.getSelectedFile().getName()));   Prints csv. But still returns false when I enter:  System.out.println(FilenameUtils.getExtension(fc.getSelectedFile().getName()) == "csv");


How is it possible to post an empty answer?

This  seems to be complete empty:      Is this a bug, or did somebody find a way to circumvent the character limit.


composer global update      Changed current directory to /home/ckosloff/.composer Loading composer   repositories with package information Updating dependencies (including   require-dev) Your requirements could not be resolved to an installable   set of packages.      Problem 1       - drush/drush dev-master requires codegyre/robo ~1.0.0-beta1 -> satisfiable by codegyre/robo[1.0.0-beta1] but these conflict with your   requirements or minimum-stability.       - drush/drush dev-master requires codegyre/robo ~1.0.0-beta1 -> satisfiable by codegyre/robo[1.0.0-beta1] but these conflict with your   requirements or minimum-stability.       - Installation request for drush/drush dev-master -> satisfiable by drush/drush[dev-master].   The above is what I get when running composer global update.    Steps taken:   I updated composer to latest build via self-update   I added the line minimum stability:"dev" to composer.json      Drush is not getting updated to the latest version. How can I solve this?


What's the difference between multicore proc and multiproc system?

I wonder what's the difference between a dual core computer and a computer with 2 processors on the mother board.. I think it's something related with the threads but a I don't understand it very well..


I want explode to return an empty array if the delimiter is not found.  Currently, I do something like this to get the explode behavior I want:              if (strpos($line, ' ') === false) {                 $entries = [];             } else {                 $entries = explode(' ', $line);             }   There must be a more concise way of getting this behavior without having to use preg_split. preg_split has its own behavior that is also undesirable, such as including the delimiter in the resultant array entries.


Input languages mixed up after user switch

Running the latest version of Windows 10 (but same thing in 1903 as well) I often stumble into a particularly annoying bug. I have two user accounts with different input language pairs (eng/rus and eng/ukr) and when switching user accounts I get my input languages broken (i.e. instead of eng/rus it would show eng/ukr or eng/rus/rus) and my typing experience is terrible.  I contacted MS support a number of times and it was awful. They tried all workarounds they could think of (including clean Windows install) but nothing helps. Ultimately they asked me to post a Windows Feedback post but of course it just hangs there with no comment or work done.  How do I get the reported Windows bug to get actually fixed?  I understand I can switch to Linux but I'm afraid of other bugs I can encounter there too.  The screenshot above demonstrates how another language option is added for no reason.    EDIT  Attached registry screenshots per comments


Should I be worried that whenever I start my computer a tab opens and on this tab it is a blue screen with a little white flashing line as if I were going to type something and it says at the top,"C:\WINDOWS\System32\WindowsPowerShell\v1.0\powershell.exe" This started yesterday and I don't know what to do because I am bad with computers and have never seen this before.


I'm using a simple bibliography like this  ... \nocite{*} \bibliographystyle{acm} \bibliography{refs} ...   and I would like to either replace the numbers ([1], [2], ...) in front of each reference with some other symbol (e.g. dots) or just remove them altogether.  Any ideas?  Edit: I am using the article class.


Check if n*m area can be filled with a*b sized tiles and find the remainder

How can I mathematically check if $n\times m$ area can be filled with pieces with $a \times b$ area and find the remainder?  For example, can $6\times 6$ area be filled with $1 \times4$ tiles? My made up notation and answer is as follows:    6*6 = 6*(1*4) + 6*2   6*2 = 2*(4*1) + 2*2   6*6 mod 1*4 = 2*2 hence it can't be filled with 1*4 tiles.   This one is just written to fit the answer I've found mechanically and not valid notation. Is there a valid rigorous way to do this for any $n\times m$ sized area and $1 \times4$ sized tiles?   How to find the area of the reminder?


custom reject edits should be shown in popup

Why is the actual custom message not shown?  I may agree with the custom message that the other person used...


Execute remote commands, completely detaching from the ssh connection

I have 2 computers, localpc and remoteserver.   I need localpc to execute some commands on remoteserver. One of the things it needs to do is start a backup script that runs for a number of hours. I would like the command on localpc to “fire” and then be running totally independent on remoteserver, like localpc was never there in the first place.   This is what I have done so far:  remoteserver contains has the script:  /root/backup.sh   localpc is scheduled to run this:  ssh root@remoteserver 'nohup /root/backup.sh' &   Am I doing this the right way? Is there a better way to do this? Will I run into any trouble doing it this way?


How do the rules handle dropping an extremely heavy object from far up to create an explosive effect?

The situation is as follows:  Boris is a 13th level Illusion Wizard. Boris and his party have proximity to BBEG's hideout city and want to do as much damage as possible to both the city (buildings & infrastructure) and its inhabitants. They have a plan:  They have a method for reaching a height of up to 1km above ground level (whether it be an airship or repeated casts of the Fly spell), and Boris has a plan for eviscerating the BBEG's evil city. He flies up 1km above the city, and begins casting Creation at 7th level to create a 25ft long pointed Tungsten rod in mid air over the city. Tungsten, as per (somewhat rough) 5e rules, should be classed as a non-precious metal - so the rod lasts for a total of 12 hours.  Immediately after being cast, it should begin falling towards the city, and quickly reach terminal velocity. Moments before it hits ground, Boris will use his 6th level feature Malleable Illusions to change the form of the Rod to a 3375 ft3 cube of pure tungsten. The cube has a mass of ~ 1844.5 Metric tonnes (1,844,488.46 kg or 4,066,400.99 lbs for reference), and impacts directly in the centre of the city.  In the real world, if an object such as that had enough mass & velocity, it could generate explosive force equivalent to an atomic explosion.  Assuming any direct reference to how this would function in real life, some form of explosion (AOE damage) would be caused.  According to the rules what happens if I do this? What effects does it cause?  What rules exist that would relate to this scenario - specifically - to the idea that simply dropping an extremely heavy object would displace (with explosive force) a large area of mass at its impact?


What should I do about `javac` command not running?

$ file /etc/alternatives/java /etc/alternatives/javac /etc/alternatives/java:  symbolic link to /usr/lib/jvm/java-11-openjdk-amd64/bin/java /etc/alternatives/javac: broken symbolic link to /usr/lib/jvm/java-11-openjdk-amd64/bin/javac


Ubuntu - One process running - Tons of memory used

I've installed Ubuntu using the Microsoft Windows Installer, and it's running pretty slow. I've got 3.8 GB ram on my computer, and by running free -m I'm getting the following results :               total       used       free     shared    buffers     cached Mem:          3920       3440        479          0       1174       1457 -/+ buffers/cache:        809       3110 Swap:          255          0        255   Only 479 out of 3440 MB is free, while to only process running at the moment if Firefox. I've changed the swappiness to 10, but still no change is seen. I'd like to know  why so much memory is used and how could I fix it and possibly make my computer run faster. Any solution would be grateful , thanks in advance !


Converting string with month that is not integer to datetime

I have strings in the format      Mar 25 2013 6:30PM   and I want to convert them to datetime objects in the format      2013-03-25 18:30:00   how would I go about doing this?


My gained reputation for today is not showing up on the Achievements dropdown

I've made 30 points on  today.   But this reputation is not showing up in the Achievements dropdown: accessible by clicking the icon to the right of the Inbox button.  My reputation counter is OK though.  Following the +2 on this question, I can see the +10 reputation for meta, but not the points for SO.


I have been cracking my fingers for 2-3 years and on the first year I was told that I'm going to get arthritis because of it.  I've been researching this since the first year and I've never gotten an answer. Most people say either Yes, No or I don't know.  Arthritis is mainly cause by bones rubbing together and cracking fingers is just air sockets poping.  I've asked my biology teacher and he said that he's not sure. He then explained to me that the cracking sound from people cracking their fingers is just air sockets poping.  So can finger cracking cause arthritus?


Does the Stormbreaker follow the same worthy rules as Mjolnir

In Avengers: Endgame, there was a moment when Thor summons the Stormbreaker and Thanos catches it in between and uses it to beat Thor.  Just thinking if anyone can pick up Stormbreaker or if it is the same as with Mjolnir.


How to extract array from dataset string?

I'm scraping a webpage and need to use dataset to get the information I need. The dataset that I can't handle is formated like <... data-info='["a","b","c"]'>. I can extract the dataset and get an array containing eg. info: "["a","b","c"]" but I can't make it an array to get the data from it.  From what I understand dataset always returns strings and in this case the string is formatted as an array. I've tried using the split() function but can't seem to make it work the way I want to.  // myElements is an array of the elements i want by // const myElements = [...querySelectorAll('myQuery')] const myObj = myElements.map(a => ({ name: a.textContent, info: a.dataset.info }))   This gives me an array of objects {name: "Some name", info: "["a","b","c"]"}. Since info is a string I can't use it the way I want to, so I tried:  const myNewObj = myObj.map(a => ({     name: a.name,      info: a.info.split(/(?:\[")|(?:",")|(?:"\])/g) }))   This comes close to what I want with {name: "Some name", info: ["","a","b","c",""]}  The problem is that the first and last entry is empty.  I could add .filter(a => a ? true : false) which works, so by writing this question I've solved my problem. But I find the resulting code messy and would love your input on better ways to solve it!    Solution (see linked question):  const myObj = myElements.map(a => ({ name: a.textContent, info: JSON.parse(a.dataset.info) }));


macOS windows requiring an explicit click to make active, before UI elements inside can be clicked

I'm a new Mac user, having been issued with a MacBook Pro when I started a new job three months ago.  A Windows and Linux user before, I'm now getting quite used to the differences with using Apple's desktop environment.  One thing that is still slowing me down a little is the requirement to explicitly click in an application window to make it active, before the UI elements inside that window can be interacted with.  For example, if I have two browser windows open side by side with the left one active, it takes two clicks to follow a link in the right hand window: one to make the window active, one to click the link.  This is in contrast to Windows or Linux, where you can click on a UI element in a inactive window and that single click will both activate the window and the element in it.  A similar issue is trying to copy and paste text between windows.  I can select and copy text in an active terminal or editor, then paste it into another with 'right-click, Paste' but that doesn't activate the window.  I still need to left-click the window to activate it before I can type into it.  In Windows and Linux, the right-click to paste would also activate the window.  If I was pasting a command into a terminal, I could then just hit Enter to run it, whereas an extra mouse click is required on my Mac.  This feels a little cumbersome.  Can this behaviour be adjusted to resemble Windows and Linux?


I'm creating a module in Drupal 8 and I need to define a relative path to mymodule to pass it on a JavaScript file like this.  $scope.getPlatformIcon = function (_platform) {      var modulePath = "/modules/mymodule"      switch (_platform) {          case "youtube":          case "twitter":          case "instagram":          case "facebook":              return modulePath+"/img/"+_platform+".png";      }      return false; };   In Drupal 7 I could use the following.  var modulePath = Drupal.settings.mymodule.basePath;   For the Drupal 8 root directory, I could use the following.  drupalSettings.path.baseUrl   I didn't find how to get the module path.  How can I do it with Drupal 8?


How can I write a Comparator comparing multiple arguments?

Im trying to write a Comparator which compares two objects of the class Coordinate. The Coordinate class is Pretty simple:   public class Coordinate {      private int x, y;      public Coordinate(int x, int y) {         this.x = x;         this.y = y;     }      public int getX() {         return x;     }      public void setX(int x) {         this.x = x;     }      public int getY() {         return y;     }      public void setY(int y) {         this.y = y;     }  }   Now I want the Comparator to compare the x and the y value for two instances of the class Coordinate. Here is an example: I have a Coordinate c1 which has x = 42 and y = 23. My second Coordinate c2 has x = 23 and y = 54. Now i put them both in an ArrayList an want to sort the List. I wanted to be sorted like the following: The Coordinate with the lowest y value goes Always first, when you have two Coordinates having the same y value the Coordinate goes first which has a lower x value. Example:    c1 (y = 4, x = 5 ) < c2 (y = 4, x = 6) < c3 (y = 5, x = 2)     So how can I write a Comparator for this Purpose? Thank you very much!


i am confused about using the "ch" as there are three sound starting with "ch" as-/k/sound, and like these. is there some important rules to find out word formation?.someone please help me.


Is the density of X always less than or equal to the spread of X? If not, can someone help me find a counter example?  $s(X) = sup ( \vert A \vert : A \textrm { is a discrete subset of } X ) $  $d(X) = \min ({ \vert D\vert : \overline{D} = X})$


Prove that $|x|<1$ implies that $\lim_{n \to \infty} x^n=0$

Show that $|x|<1$ implies that $\lim_{n \to \infty}x^n$ = 0.   Can anyone help me define my $N$ (as used in the formal definition of a limit) in terms of $\varepsilon$? I define $x$ as $\dfrac{1}{1+p}$ where $p>0$ but I am not sure how also to define $N$ since both $P$ and $\varepsilon$ are variable.


Regex multiline match from specific word until the first match of an end character

I have the following string:  foo  1  2  3  bar ! !  2  3  bar !   And I would like to match:  foo  1  2  3  bar !   My current regex is (?s)foo.*! , but that matched everything  Here is my regex example:


All the permutations that commute with (1 2)(3 4 5) in $S_5$

Determine all the permutations $\sigma \in S_5$ that commute with the permutation $\alpha = (1 \space 2)(3 \space 4 \space 5).$


my App Store is broken for Mac High Sierra 10.13.5 please help

I will click featured or something else and it automatically redirects me to updates it is making me mad someone please help me out thanks I appreciate it


Rounding Floating Point Number To two Decimal Places in C++

After Rounding to two decimal places, i alwayse get the same value float TestT =round(t*100)/100;   i would like to round it and fix it to two decimal places: 0.009999 -> 0.01


Why does arr.map(parseInt) not work in JavaScript?

I feel like I'm doing some noobish overlooking of things. Can anyone help me understand why the following doesn't work  ["1.1", "2.2", "3.3"].map(parseInt); //=> [1, NaN, NaN]   This works though ???  ["1.1", "2.2", "3.3"].map(function(num) {   return parseInt(num); }); //=> [1, 2, 3]   This seems to work too  ["1.1", "2.2", "3.3"].map(Number); //=> [1.1, 2.2, 3.3]


Functional equation $f(xy)=f(x)+f(y)$ and continuity

Prove that if $f:(0,\infty)→\mathbb{R}$ satisfying $f(xy)=f(x)+f(y)$, and if $f$ is continuous at $x=1$, then $f$ is continuous for $x>0$.   I let $x=1$ and I find that $f(x)=f(x)+f(1)$ which implies that $f(1)=0$. So, $\lim_{x\to1}f(x)=0$, but how can I use this to prove continuity of $f$ for every $x \in \mathbb R$?   Any help would appreciated. Thanks


Is there any point to posting app bug reports?

I've discovered some bugs regarding the SE iOS app but recently learned that there are no active personnel on the development team for the apps. If this is the case, is there any reason to post bug reports for these apps as a sort of backlog if development does start again in the future? Or are there really no plans to do so making bug reports a waste of time?


How do I prove that 15462227 and 15462229 relatively prime?

Are 15,462,227 and 15,462,229 relatively prime?   How do I construct a proof for this.   I know that for n and n+2 to be relatively prime it is the case that n has to be odd. Is this the only requirement for these numbers to be relatively prime?


If each box of cereal contains 2 different prizes at random and there are 7 prizes total, how many boxes would you expect to open in order to collect all 7 prizes?  The standard version of this problem has 1 prize per box.    Can this be generalized for n total prizes and k different prizes per box?


My iPhone does not have that much space left, so I went into storage and it seems this Other is taking up a lot of space and I’m wondering how I can minimise this. I know there is another question exactly like this, but from what I can tell it doesn’t seem relevant to iOS 11 (which is what I’m on).


When do you use the plural of "medicine"?

Or in other words, I am asking: How do you "count" medicine? Is the word "medicine" like "gas" where a collection of gas is still called gas:     The air was filled with nitrogen gas.   Instead of:      The air was filled with nitrogen gases.   And only in terms of types of gases do you use the plural:     There are many types of gases in the atmosphere.   So, in the following example:     He gave him some medicines.   Does that mean he gave him different types of medicine, or different amounts?


what is a good adjusted R square value for any multiple regression model or it depends? If it depends then what are the conditions?


Speed of object towards a point not in the object's trajectory?

Trying to study for my mid-term, but I'm having slight difficulties understanding what I'm supposed to do in this one problem:  A batter starts running towards first base at a constant speed of 6 m/s. The distance between each adjacent plate is 27.5 m. After running for 20 m, how fast is he approaching second base? At the same moment, how fast is he running away from third base? (see image below)    This is what I have so far:   Let $d$ be the distance the batter has run thus far The distance between the batter and first base is 7.5 m The distance between the batter and second base is $\sqrt {27.5^2 + (27.5-d)^2}\ $, or approx. 28.5044 m when $d = 20$ The distance between the batter and third base is $\sqrt {27.5^2 + d^2}\ $, or approx. 34.0037 m when $d = 20$   No need to hand feed me the answer, I'd just like a bit of insight on how to solve the problem.


dpkg: error processing linux-generic unmet dependency error

dpkg: error processing linux-generic, un met dependency error when sudo apt-get install -f  Setting up linux-image-generic (3.2.0.60.71) ... dpkg: dependency problems prevent configuration of linux-generic:  linux-generic depends on linux-image-generic (= 3.2.0.58.69); however:   Version of linux-image-generic on system is 3.2.0.60.71.  linux-generic depends on linux-headers-generic (= 3.2.0.58.69); however:   Version of linux-headers-generic on system is 3.2.0.60.71. dpkg: error processing linux-generic (--configure):  dependency problems - leaving unconfigured No apport report written because MaxReports is reached already                                                               Errors were encountered while processing:  linux-generic E: Sub-process /usr/bin/dpkg returned an error code (1)


How does LaTeX implement the differences between the dashes?  -, --, and --- all print different dashes, but - is not an active character: it has catcode 12, the same as digits like 2.


Good book for an introduction to differential equations

I've looked at differential equations, but nothing past what you would learn in Calculus I and II (slope fields, separation of variables, etc.). Is there a good book out there which provides a comprehensive introduction while not being too superficial? I checked out some other questions like this one and found Differential Equations With Applications and Historical Notes, which looks very cool, but I just want to make sure it is the best one to get before I get it. Thanks!!


I was wondering why using foo.bar@gmail.com works but not foo.bar@outlook.com.  In Gmail, foo.bar@gmail.com and foobar@gmail.com (and any combination of periods in the username) is equivalent.  Is this a hidden feature in Gmail?


How to find the running network services and the port and user

I want to find a list of all network services running on my system, including details of the port and services and the users. I know that I need to use netstat, ps and fuser. but I don't know how to write the command. Do I need to write a shell script to find all of them? or I can use in a line of commands? Thanks for your help.


Analyzing limits problem Calculus (tell me where I'm wrong).

I came accross: $$\lim_{x \to\ 0}\frac{x\cos x - \log (1 + x)}{x^{2}}$$  I tried the following please tell me where I 'm wrong:  $$\lim_{x \to\ 0}\frac{x\cos x - \log (1 + x)}{x^{2}} $$  $$\text{(Dividing by }x)$$   $$=\displaystyle\lim_{x \to\ 0}\dfrac{ \cos x - \dfrac{\log (1 + x)}{x}}{x} $$  $$=\lim_{x \to\ 0}\frac{\cos x - 1}{x} $$  $$=\lim_{x \to\ 0}\frac{-2\sin^{2} \dfrac{x}{2}}{x} $$  $$=\lim_{x \to\ 0}\frac{-2x\sin^{2}\dfrac{x}{2}}{(\dfrac{x}{2})^{2}\times 4} $$ $$\lim_{x \to\ 0}\dfrac{-x}{2}=0$$ But Answer given is $\dfrac{1}{2}$  Please Help.


Remove and delete certain local accounts

How can I delete a user from the command line?     I am just starting working at a college and I'm inheriting a unintelligible mismash of local and domain accounts across a span of computers ranging from XP to Windows 8.  with upwards of two thousand computers that need to be gone through and remove anywhere between no and 5 local users accounts (so that people will start actually using their domain counterparts)   I've seen people saying  which apparently misses possibly some stuff in the registry and doesn't remove the folder for C:\users\username either  I've seen people recommending  which seems like it would get the job done, and has some filters, but has no way for me to specify which accounts to leave or delete other than direct interaction or filtering based on time (which won't work because I am changing the account they should be using)  Also, I would prefer to stay away from downloading and running a file on all of the computers and stick to regular commnands/vbscript/powershell/stuff  Most of the computers have either one or two local accounts that I would want to remove. The rest I would want to spit out to a file for my manual review (some of them have been embedded in systems and would need undoing by hand) but I can worry about that part in the script I'll be writing.   I am looking for a command line way or a set of steps to delete a given user. If doing net user username /del and then deleting the relevant registry keys is that, then please give some sources.


Strict equality works on variables but not on objects

I have a variable defined as:  var o = new String("0");   In console when i write:  o === o   it returns true but when i write:  new String("0") === new String("0")   it returns false  I don't understand why is it working on variable references but not on objects?  I tried it as:  (new String("0")) === (new String("0"))   because the problem may arise due to operator precedence, but it still returns false


How can I install the BoolTool?  The  lead me to  but don't tell me whether to use "BoolTool 0.1.rar - BoolTool 0.2 release" or "BoolTool 0.2 rar - BoolTool 0.2" (and those names are confusing). The instructions are also unclear in other ways. For example, "5. Save in somewhere as "BoolTool.py" if it's not"—does that mean manually change the extension to ".py"?  A step-by-step list with no assumption that I know Github or ".rar" or "Raw" or ".zip" or ".py" would be very helpful. Thanks!


I had to keep using 19.04 for a while after it was discontinued for a variety of reasons. I would now like to move up in the world to 20.04. I have tried following a number of paths, for example the sequence of steps which is described here:  In brief, this means, eg: sudo sed -i 's/disco/focal/g' /etc/apt/sources.list sudo apt update && sudo apt full-upgrade  The error message I get, which seems to be reproduced across the internet, is as follows: E: The repository 'http://ppa.launchpad.net/deadsnakes/ppa/ubuntu disco Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. N: Skipping acquire of configured file 'universe/binary-i386/Packages' as repository 'http://miktex.org/download/ubuntu xenial InRelease' doesn't support architecture 'i386' E: The repository 'http://ppa.launchpad.net/maarten-baert/simplescreenrecorder/ubuntu disco Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.  I guess it's been long enough now though that somebody somewhere must have found a fix to this, no? Does anybody know what to do? Thanks!


How to prove that $f$ is differentiable at every point beside $x=-1$?

Consider $f(x) = |x+1|$. I want to show that for every $x_0\neq-1$ , $\lim_{h \rightarrow 0}\frac{f(x_0+h)-f(x_0)}{h}$ is exist. So far i just wrote the definition, and looked on 2 options:When $x>-1$ and $x<-1$. But, i got stuck when i go the definiton of differentiabily in those points, because what the meaning of $\lim_{h \rightarrow 0}\frac{|x_0+h+1|- |x_0+1|}{h}$? tnx!


Proving the second root of a quadratic equation

If $\alpha$ is a root of the equation $4x^2+2x-1=0$, then prove that $4\alpha^3-3\alpha$ is the other root. How do I proceed? The sum of the roots, the product of the roots lead me nowhere. Should I find the roots of the equation and substitute in the given two expressions of $\alpha$ and check whether manipulating the first root gives me the second root (which seems much complicated), or is there any other way?


In my campus, some people they are using netcut in Windows and they are blocking us not to use Internet.  Since I am a Ubuntu user, I can't install  neither nutcut nor netcut-defender to protect and even I tried TuxCut. It's is also not working properly.  Can any one give me the right solution for this?


Removing extra string from text column in Attribute Table to make numeric column from number part using ArcGIS Field Calculator?

I received a shapefile about invasive species. I am using ArcGIS 10.2 for desktop. In Attribute Table, there is column called "Infested_Area" and its got number mix with text, for instance "9100 sq feet". Since I can not run statistic on string I was wondering if it's possible to create a new filed and somehow get rid of the text portion of it and only have number!


bash: how do you return file extensions?

I want to write a script to return just the extension of the input file name. For example, textfile.txt should return txt.  I'm new to Linux and bash, and I'm trying to learn how to write basic scripts. Thanks!


Why squared residuals instead of absolute residuals in OLS estimation?

Why are we using the squared residuals instead of the absolute residuals in OLS estimation?  My idea was that we use the square of the error values, so that residuals below the fitted line (which are then negative), would still have to be able to be added up to the positive errors. Otherwise, we could have an error of 0 simply because a huge positive error could cancel with a huge negative error.  So why do we square it, instead of just taking the absolute value? Is that because of the extra penalty for higher errors (instead of 2 being 2 times the error of 1, it is 4 times the error of 1 when we square it).


My requirement is to replace the html tags in the string.   I have tried using Jsoup and other parsers . I tried with regular expressions .   But the problem is they are removing content which is not html also.  Example:
hi Hello
Second Hi Hello If BB &amp; this is true After body in message body normal text.   Expected output:  hi Hello Second Hi Hello If BB  this is true After body in message body normal text   Actual output:  hi Hello Second Hi Hello If BB  this is true After body in message body normal text   Could someone let me know the possible approaches?


How do I make defuse kits purchasable without making it competitive?

I want to play on de_lake or any of the other wingman maps with competitive mode on but everytime I try play them and use game_type 1 it changes it to arms race. Is there any way to either do the commands for competititve (free armour, friendly fire and defuse kits purchasable) or make it competitive?


I have 8/3 Romex wire and shop is 60 ft. From my house. Heard to many of different ways to do it, but I want it to be down safe and the right way. I need to know what size of subpanel and what breakers can I use? Wanting 3 outlets, 1 for lights and stereo, 1 for tools 15amp on tools nothing bigger than that and 1 for misc. Main panel in the house is 150amp cutler-hammer with 6 spaces still open.


When i try to install KNotes by command "sudo apt-get install KNotes"   It shows following  Reading package lists... Done Building dependency tree        Reading state information... Done E: Unable to locate package KNotes


Can we be notified if a question of ours is being discussed on meta?

Instead of , would notification be valuable?  It might engender a more hostile debate, such as happened . I'm not sure if notification is the exact mechanism I'm asking for... at the same time, it might also lead to the opposite–a greater opportunity for all involved to have a voice.  I realize that it would be just as easy for whoever asked the question to link to the meta discussion, but I wonder if (a) everyone would always remember, or think, to do so, and (b) if the risk of retaliatory behavior would be increased if there was either (automatic or manual) indication of the meta talk.  Thoughts? (I tagged this as a feature request even though I'm not 100% sure I'm asking for anything, or if I am, what precisely it is–apologies. I'm mostly wondering about the pros, cons, and alternatives.)


I'm trying to find a book I remember reading, one I'd like to re-read.  I saw it  probably decades ago.   Basic premise is that earth has been stuck in a zone that somehow suppresses intelligence.   When it leaves, everyday people go genius.      I remember a throw away line early in the book with a scene about a kid who was toying with high mathematics and saying later that day he had reinvented calculus.    I remember it causing chaos on Earth -- and I remember them doing some sort of space journey later in the book to test the theory that there was a zone of IQ suppression.   I think I remember reading it as a small paperback. There might have been something about some animals becoming sentient as well, unless I'm confusing still another story.  I don't remember the title or author.   I'm thinking it had a cover possibly with a chimp riding an elephant into a farm or low-urban area or something  -- unless my memory is mixing books.  This was long before Vernor Vinge's books.


On python, how can i print up to a certain amount of random numbers from a list of generated numbers?

I have it set so the user enters a max input and then the program figures out which numbers are prime and then prints it all to a file. But at the moment it only prints the closest prime number to the upper input. I need it to print 20 random numbers and put them on a file. Also with print (num) 20 times it can print 20 different outputs, but if I add print (num) 20 times it prints the same number 20 times  import random #Always start at 2 lower = 2 #Take input from the user upper = int(input("Enter maximum size for prime number to be: ")) for num in range(lower,upper + 1):   if num > 1:     #Prime numbers are greater than 1     for i in range(2,num):         if (num % i) == 0:             break         #End program if number is 0         #Print results     else:         randomprimes =(num)         primes =(random.choice(randomprimes))         import sys         former, sys.stdout = sys.stdout, open('Prime Number Generator Output.txt', 'w')         print (primes)         results, sys.stdout = sys.stdout, former         results.close()


How to unmask and start a dhcpd service?

I was about to start my dhcpd service but couldn't do it since it was masked. I tried systemctl unmask dhcpd.service but it does not work. Any suggestion?


Display lines in last 10 minutes with specific pattern in logs

I need to display lines with Error occurred in last 10 minutes of a log file.   Aug 26 10:50:42 Normal line. Aug 26 10:51:23 Normal line. Aug 26 10:55:33 Error line. Aug 26 10:56:45 Normal line. Aug 26 10:58:12 Error line. Aug 26 11:02:31 Normal line. Aug 26 11:03:32 Normal line. Aug 26 11:04:11 Normal line.   Suppose above sample of log file. I want to display only following two lines  Aug 26 10:55:33 Error line. Aug 26 10:58:12 Error line.   I am using AIX.


Java: How to set Precision for double value?

I was working with numbers recently and I had a situation where I want to set the precision of a double value say to 6 digits or 4 digits, depending on the value stored in the database.  For example, If in the database the precision is set as 4 digits then the output must look as,  10.0000.   I tried with DecimalFormat and using the string ##.####, but it is annoying to use symbols everytime.   Is there any better approach, say something like below:  Double value = 10.0; value.setPrecision(4);


Evaluate $\sum_{k=0}^{n} {3n \choose 3k}$. It's not hard to evaluate by putting roots of unity.  Therefore, I would like to see some solutions using elementary mathematical stuffs but not roots of unity.  And the answer is $\frac{1}{3}(2^{3n}+2(-1)^n)$


My OSM country roads network is not routable

I need a routable shapefile in order to execute pgrouting algorithms. I download a national zip from  and import the roads shapefile in my PostgreSQL/PostGIS database through QGIS. Then I execute the following SQL commands (following the workshop instructions):  ALTER TABLE roads ADD COLUMN length integer; UPDATE roads SET length = st_length(st_transform(geom,2100)); ALTER TABLE roads ADD COLUMN reverse_cost double precision; UPDATE roads SET reverse_cost = length; ALTER TABLE roads ADD COLUMN "source" integer; ALTER TABLE roads ADD COLUMN "target" integer; SELECT pgr_createTopology('roads', 0.0005, 'geom', 'id'); SELECT seq, id1 AS node, id2 AS edge, cost FROM pgr_dijkstra('             SELECT id AS id,                      source::integer,                      target::integer,                      length::double precision AS cost                     FROM roads',             number1, number2, false, false);   where number1 and number 2 are values I define manually. All commands are executed with success but the last one. The query does not work in most cases, although there is an apparent road link, because, as I zoom in the layer, I can see breaks in the network.  I searched similar problems in the forum and I found suggestions that I should fix my shapefile in order to make it routable. I tried the GRASS commands split and clean but I met problems. With split I had no result since it said it found too many errors. With clean I had a cleaned shapefile but a non-routable one again.  Is there another way to make my dataset routable?


I started my Ubuntu 15.10 and am unable to open the software updater app. I keep getting the following error  SystemError: E:Malformed line 55 in source list /etc/apt/sources.list (dist parse)   I tried purging the app and reinstalling, but still get the same error. Any suggestions?


What do you call the connector type which is soldered on PCB and it holds cables by pressing on them by screws?

Here is a picture of two of them:    I searched for these connectors in  and  for an hour, but couldn't find anything similar. Can you please name these connectors for me and/or give a link to their subcategory in one of these part seller websites?


I have been reading some Boku no Hero Academia and in some chapters (only very few) there have been panels, which looked like sketches and not like the rest of the manga. Since it were only single panels, I didn't think much of it. But while reading chapter 182, there have been whole pages like that (s. picture below).   Did the artists run out of time and so, they weren't able to complete all pages? Or is there a different reason for this?      )


backshifting of tenses (optional back shifting)

Let's first talk about simple present tense. John : "I have a fever." John said that he has a fever. Here no change in tense because John still has a fever.  Now take an example of present perfect tense. John : "I have lost my keys." John said that he has lost his key. Here no change in tense because the effect of losing key (he can't get into his home) can still be seen, heard at the time of reporting.  First tell me is this 'has lost' correct in indirect speech under the condition that effect of loosing key can still be seen at the time of reporting ?  Now my question is something which is not an example of reported speech. 1) "I noticed that the clock has stopped." And 2) "The president learned that the earthquake has caused havoc all across the country.  Are these two sentences grammatically correct under the condition that clock has recently stopped and its effect can still be seen ? And under the condition that earthquake has recently come and its effect such as havoc all across the country can still be seen ?  You see my take on it is, if the simple present tense is not back shifted under the condition that words are still true at the time of reporting then present perfect tense can also be left unchanged under the condition that situation is still relevant at the time of reporting even if the main verb is in the past tense.   And I also feel that grammar rule is quite logical and correct but if the situation is still relevant then I believe that back shifting of present perfect tenses become optional. So what do you think about this. Did I get it right?


Is Foreign Direct Investments per capita a count variable?

I was doing a multiple linear regression in which the dependent variable was the FDI per capita. However, it turned out that the data has a negative binomial distribution. That is why I tried to use the negative binomial regression, which works properly.   However, I have a fundamental question is it possible to consider FDI per capita as a count variable. Since negative binomial regression work with count data.   By definition count variable is number of accidents, number of suicides.  So theoretically FDI per capita is also considered to be a count variable, since it is a number of FDI per capita. My data is integer and non-negative.   Correct me if I am wrong.


How would I prove that if $f: \mathbb R^2 \to \mathbb R$ is a function such that  $$\lim_{(x,y)\to(a,b)} f(x,y) = L$$  and for every $y_0 \in \mathbb R$   $$ \lim_{x\to a} f(x,y_0) = L'_{y_0}$$  and for every $x_0 \in \mathbb R$   $$ \lim_{y\to b} f(x_0,y) = L''_{x_0}$$  then  $$ \lim_{x\to a}\left(\lim_{y\to b} f(x,y)\right)  = \lim_{y\to b}\left(\lim_{x\to a} f(x,y)\right) = L$$


Remove files from directory that do not have corresponding pair in another directory based on file prefix?

I have two directories, dir1 and dir2 and I want to remove files in dir2 that do not have a corresponding pair in dir1.  The pair is defined by the first three fields of the filename prefix separated by an underscore.  For example:  dir1 contains:  U006_S2_pr_hrrre_1760-1790_fil.csv U006_S2_ta_hrrre_1760-1790_fil.csv   dir2 contains:  U006_S2_ep_prc4_1660-1790_fil.csv U006_S2_ep_prc8_1760-1899_fil.csv U006_S2_pr_prc8_1260-1090_fil.csv U006_S2_ta_prc4_1860-2790_fil.csv   I would want to get rid of   U006_S2_ep_prc4_1660-1790_fil.csv  U006_S2_ep_prc8_1760-1899_fil.csv   but keep the remaining files. There are thousands of files in each directory.  All files in dir1 have a corresponding pair in dir2, but dir2 has many extra files without corresponding pairs in dir1.


Drawing perpendicular lines at start and end of lines using ArcGIS Desktop?

I have some lines. I want to draw perpendicular lines at the start and end of the lines, on both sides of the lines.  Can somebody help me in Python?  I am using ArcGIS.


Just installed Ubuntu 16.10, and now I am in the login loop. I can use ctrl alt f3 to open the console, but dunno what kind of command would fix this. Can you please help me?


A regular expression for splitting where the delimited is contained in angle brackets

Consider  <_2017-05-15 type="Double">-1.920992100000000E+05</_2017-05-15>   How can I treat <...> as a delimiter when attempting to split this string (in order that I can pull out the number -1.920992100000000E+05?  I tried <.*> (and even \\<.*\\>) but that is a match for the whole string.  For what it's worth, I'm using Java.


How do I install the cs_CZ.ISO8859-2 locale on Ubuntu 12.04

I need the cs_CZ.ISO8859-2 locale to exist on Ubuntu 12.04 so a specific unit test can pass. The test makes the following call:  std::locale("cs_CZ.ISO8859-2")   On my OS X Lion install, this locale does exist, so the call to std::locale should work:  $ locale -a | grep cs cs_CZ cs_CZ.ISO8859-2 cs_CZ.UTF-8 $   However, on my Ubuntu 12.04 install, there is only a UTF8 variant, and no ISO8859-2 version of the cs_CZ locale, despite having installed language-pack-cs:  $ dpkg -l | grep language-pack-cs ii  language-pack-cs                       1:12.04+20120417                        translation updates for language Czech ii  language-pack-cs-base                  1:12.04+20120417                        translations for language Czech $ locale -a | grep cs_ cs_CZ.utf8 $   The unit test fails on this machine. Running the unit test under strace shows that it really is looking for the ISO8859-2 variant and not finding it anywhere:  open("/usr/lib/locale/cs_CZ.ISO8859-2/LC_CTYPE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) open("/usr/lib/locale/cs_CZ.iso88592/LC_CTYPE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) open("/usr/lib/locale/cs_CZ/LC_CTYPE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) open("/usr/lib/locale/cs.ISO8859-2/LC_CTYPE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) open("/usr/lib/locale/cs.iso88592/LC_CTYPE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) open("/usr/lib/locale/cs/LC_CTYPE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) open("/usr/share/locale-langpack/cs_CZ.ISO8859-2/LC_CTYPE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) open("/usr/share/locale-langpack/cs_CZ.iso88592/LC_CTYPE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) open("/usr/share/locale-langpack/cs_CZ/LC_CTYPE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) open("/usr/share/locale-langpack/cs.ISO8859-2/LC_CTYPE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) open("/usr/share/locale-langpack/cs.iso88592/LC_CTYPE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory) open("/usr/share/locale-langpack/cs/LC_CTYPE", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)   I know absolutely nothing about locales, i18n, etc. However, I would like to get this test passing, and changing the test is not an option. If anyone can offer any insight into how to make this locale exist on Ubuntu 12.04 I would appreciate it greatly.


What is the expected result for the number of heads obtained in this coin/dice flipping example?

Suppose you roll one fair six-sided die and then flip as many coins as the number showing on the die. (For example, if the die shows 4, then you flip four coins.) Let Y be the number of heads obtained. Compute $E(Y)$.  So, $E(Y)=\Sigma_{y=1}^{y=6}yP_{y}(y)$  We will define $X$ as the number on the die. Therefore:  $$E(Y)=\sum_{y=1}^{y=6}yP_{y}(y)=\sum_{y=0}^{y=6}\sum_{x=1}^{x=6}(y)P(X=x,Y=y)=\sum_{y=0}^{y=6}y\sum_{x=1}^{x=6}(1/6)\binom{x}{y}(1/2)^x$$  This inner equation is valid: $(1/6)\binom{x}{y}(1/2)^x$  Basically, it says that if I roll a 3, and I get 1 head only, what is the probability of that occurring = $(1/6)\text{[for the roll]}\binom{3}{1}\text{[from 3 rolls, we choose one head]}(1/2)^3=1/16$  Now, I need to simplify the above double sum, but I am not sure how to do it. The answer in my textbook is $7/4$, but it does not show steps. I think I am right until now, I just need help doing this summation.


How does Google Chrome manage to freeze my entire PC?

Google Chrome is the only program on my computer that can freeze my mouse.  When loading multiple tabs at once, the mouse pointer will become unresponsive, and nothing is moving on my screen.  I've never seen any other program do this.  My PC usually emits a little beep when it's done thinking.  This happens on Windows 7 on every single computer that I own.  I don't own expensive hardware, but I have Core i3's and i5's with plentiful RAM.  I know that Chrome runs as multiple processes (one for each tab I believe.)  Could this cause the issue?  Are the processes running at a higher priority than, say, the mouse drivers?  This isn't a huge problem, but I am curious about the technical reasons that cause this phenomenon.  Thanks!


dictionary with values only evaluated when selected

I have a function main that, given a string, should select one of many other functions, call it with some specific args and kwargs, and return its result. The most straightforward implementation of this is    def main(string):     if string == "a1":         return a(1)     elif string == "a2":         return a(2)     elif string == "b":         return b("foo", symbol=True)     # ...     elif string == "y":         return y()      assert string == "z", "Illegal string '{}'.".format(string)     return z("bar", 25)   but I don't like this unsightly huge conditional. More readable is perhaps    def main(string):     d = {         "a1": a(1),         "a2": a(2),         "b": b("foo", symbol=True),         # ...         "z": z("bar", 25),         }     return d[string]   This also eliminates possible typos where a key is elif'd twice – nice. Unfortunately, this initializes every entry in the dictionary just to throw away almost all of them right away. Defining d outside of main isn't a big improvement either in my case since main is only executed a few times. Adding some lambdas works    def main(string):     d = {         "a1": lambda: a(1),         "a2": lambda: a(2),         "b": lambda: b("foo", symbol=True),         # ...         "z": lambda: z("bar", 25),         }     return d[string]()  main("a")   but again, this makes the code less readable.  I'm wondering whether it's possible to define something like a dictionary iterator: With all key-value pairs specified, but the value only evaluated when picked. Perhaps there's a better idea.  Hints?


My question is quiet simple:  I have a custom object which his key field is auto-generate. It has this format: {YYYY}{0000}.  So it will be something like this: 20150150, 20150151, ... , 20150199  1th January 2016 when i will create a new item, how will it be?  20160200 or 20160001.  If it is 20160200... How can i get that 20160001?  Thanks all!


Could someone explain the main differences between Key Policy Attribute Based Encryption (KP-ABE) and Ciphertext Policy Attribute Based Encryption using an example?   I know that KP-ABE depends on the private keys associated with the person trying to decrypt the message while the CP-ABE depends more on the attributes used in encryption. I would like to see an example that explains this part more to get a better idea.


Why is the sun brighter in Australia compared to parts of Asia?

Background:  I've lived in Philippines for several years, and visited other parts of Asia occasionally (Singapore, Indonesia, Hongkong).  I just moved to Western Australia a few months ago and I realized that the sun is brighter here, in the sense that every after sunrise and every nearing sunset, the sun shines too bright that it is blinding. This happens almost everyday, so this isn't just some one off thing.  In Asia, this never occurred to me. The sun was always bearable to the eyes.  Why is this so?


Is it true that $R^n\simeq R^m$ as rings implies $m=n$?

Let $R$ be a commutative ring. We know that if $R^n\simeq R^m$ as $R$-modules for some positive integers $n,m$ then $n=m$. But is it still true when they are isomorphic as rings? Thanks!


Is a finite group uniquely determined by the orders of its elements?

Suppose we are given a finite group $G$, and suppose we know the order of $G$ as well as the orders of each of its elements.  Does this information alone uniquely determine the group up to isomorphism?  What if we add extra hypotheses about $G$ (solvable, simple, etc)?  If not, can we at least extract some useful information regarding its structure?    For example, if $|G| = 8$ and $G$ contains three elements of order $2$ and four elements of order $4$, then I know $G \cong \mathbb{Z}_4\times\mathbb{Z}_2$.


I have ubuntu 18.04 LTS installed. I want to completely update my ubuntu copy to kubuntu using cd image


After installation of Ubuntu 18.04 on a laptop computer " My name " should read "Erik Andersen",but it reaads "eRIK aNDERSEN".and of course my lock on codeword is also " inverted " ! Is there an easy way back, without a re-install! Any help will be appreciated!


Python Script to apply the Northing and Easting of a photo center .shp file to a tiff.

I have a group of tiffs I want to georeference. I have the photo centers for each of the tiffs but they are not linked. After looking at the comments I believe there would be a way to take the attribute of the .shp, Northing and Easting, and apply it to the tiff? The frame number for the photo is in the attribute table of the points. I assume you could use this to look into the folder and pull out the correct photo and reference it to said location. I hope this explains what I am looking for in a better light.


MAMP for Mac version 3.4 mysql general query log not working

This is not a duplicate of another question. I really like MAMP as it simplifies development and am just trying to figure out how to enable general query log.  I am trying to enable the general query log in MAMP 3.4 for mac  What I have tried   create file /Applications/MAMP/logs/mysql_sql.log chmod 777 /Applications/MAMP/logs/mysql_sql.log add the following by editing template my.cnf to the mysql section  general_log = 1 log = /Applications/MAMP/logs/mysql_sql.log Restart mysql   When I run queries I do not get anything written to that file.  Am I missing a step? My other changes such as mode take affect; just not this log.


Let $V$ be a finite-dimensional vector space. If $\Delta = \{(\textbf{v},\textbf{v})| \textbf{v} \in V\}$ is the diagonal subspace of $V\times V$, show that dim$\Delta$ = dim$V$.   I know this following theorem: Let $W$ be a subspace of a finite-dimensional vector space $V$. Then dim$W$ = dim $V$ if and only if $W=V$.   Then according to this theorem, doesn't it necessarily follow that if I can assume that dim$\Delta$ = dim$V$ is true, then $\Delta = V$ is true since it can be shown that $\Delta$ is a subspace of $V$ (or is that not true?)? But how can $\Delta = V$ if $\Delta$ is made up of tuples of vectors in $V$? For example, if vector $\textbf{v} = (1,1) \in V$, then $(\textbf{v},\textbf{v}) = ( (1,1), (1,1) ) \in \Delta$, but $( (1,1), (1,1) ) \notin V$. Can someone clarify this for me?


The no. of subgroups which are not normal

Let $G$ be a group. Let $t$ be the no. of subgroups of $G$ which are not normal. Prove that $t\neq 1$.  My Work:  Case 1: $G$ is abelian. Then all subgroups are normal. Hence, $t=0$  Case 2: $G$ is non abelian. Assume $t=1$. Then there is a subgroup $H$ which is not normal in $G$. Then if there is another subgroup $K$ such that $K\neq H,G,\{0\}$ then $K\triangleleft G$. Then I was going to get a contradiction using 2nd isomorphism theorem. But how can I prove the existence of such $K$? I am stuck now. Can anyone please help me?


extend virtual machine across physical machines

Is it possible for two or more physical machines to be "grouped" into one virtual machine such that the CPU cores are shared?


Share Wireless connection with Wired Ethernet Port

That's pretty much it. If I connect to the Internet on wlan0, how can I share this connection with a device plugged into my wired Ethernet port eth0?


Undesired spacing before \sqrt[n]{x}, proper way to fix?

This code  \documentclass{article} \usepackage{amsmath} \begin{document}     \[ J(\sqrt[n]{x}) \] \end{document}   compiles into this:    The spacing after the opening parentheses is ugly. What's the proper way to fix this?


Replying from Gmail with custom POP3 settings and auto selecting the associated custom SMTP settings

I set up Gmail to add a POP3 and SMTP server for sending mail. Whenever I get mail to that new address though, and I press on reply it still tries to reply by default by using my @gmail.com address.    Is there a way that when I get mail to that new POP3 account, that it will auto select the associated SMTP account?


Can I apply MacBuntu themes and icons on Xubuntu 16.04?

is supposed to be compatible with XFCE. Fonts and cursors work, but when I apply the themes and icons on Xubuntu 16.04, nothing happens.  How can I apply these icons and themes (or something similar) on Xubuntu 16.04?


Is there a built-in product() in Python?

I've been looking through a tutorial and book but I can find no mention of a built in product function i.e. of the same type as sum(), but I could not find anything such as prod().  Is the only way I could find the product of items in a list by importing the mul() operator?


Null object reference while invoking virtual method when seaching a list that is in another activity

I have kept a listview in the activity_main_one and the list is filled by an array. Now i have kept a searchview in activity_main_page to search that list. But instead i am getting an error :   Attempt to invoke virtual method 'void com.example.abc.hotelomania.MainActivity1.initList()' on a null object reference  The code of activity_main_one is in MainActivity1.class  MainActivity1.class  public class MainActivity1 extends ActionBarActivity {  String[] items; ArrayList<String> listItems; ArrayAdapter<String> adapter; ListView listView; EditText editText;  protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.activity_main_one);     initList();     items=new String[]{"Canada","China","Japan","USA"};         listItems=new ArrayList<>(Arrays.asList(items)); }  public void initList(){     adapter=new ArrayAdapter<String>(this,             R.layout.list_item, R.id.txtitem, listItems);     listView.setAdapter(adapter); } }   MainPage.class     public class MainPage extends Activity {    MainActivity1 mn;    String[] items;    ArrayList<String> listItems;    ArrayAdapter<String> adapter;    ListView listView;    EditText editText;     @Override    protected void onCreate(Bundle savedInstanceState) {       super.onCreate(savedInstanceState);       setContentView(R.layout.activity_main_page);       items=new String[]{"Canada","China","Japan","USA"};        listItems=new ArrayList<>(Arrays.asList(items));       listView=(ListView)findViewById(R.id.listview);     editText=(EditText)findViewById(R.id.txtsearch);     mn.initList();     editText.addTextChangedListener(new TextWatcher() {     @Override     public void beforeTextChanged(CharSequence s, int start, int count, int after) {     }      @Override     public void onTextChanged(CharSequence s, int start, int before, int count) {        if(s.toString().equals("")){                 // reset listview                 mn.initList();        }        else {                 // perform search                 searchItem(s.toString());        }      }      @Override      public void afterTextChanged(Editable s) {      }   }); }   public void searchItem(String textToSearch){     for(String item:items){         if(!item.contains(textToSearch)){             listItems.remove(item);         }     }     adapter.notifyDataSetChanged();     }


I'm building a druid character for an upcoming E6 game, and I'm wondering if I can get myself rage along with 6 levels of shapeshift variant druid.  Unfortunately, shapeshift is obligatory, which means no druidic avenger. Are there any feats/races/templates/whatever which could grant rage? In case it is important, flaws are allowed, splatbooks are generally allowed and we are starting on 2nd level.  For those not knowing what E6 is, here is a . TLDR version: as dnd up to 6th level, one feat every 5kxp thereafter, level adjusted races get lesser point buy but no level adjustment.


What should I ask my potential Ph.D advisor in advance, before actually signing a contract?

I'm currently applying for a Ph.D in Germany. Next week I'm sitting down with my potential Ph.D advisor to have a talk about the program.    Currently I'm collecting questions about things like   teaching duties included? working hours   what's the salary? vacation? budget for conferences?   I think I'm missing some important stuff.  My real question is: What should I ask my potential Ph.D advisor in advance, before actually signing a contract / starting?  (The question  is related, but I feel it doesn't fit my situation)


Why is power reflected when there is an impedance mismatch?

I understand that when there is an impedance mismatch between an output stage, for example from an amplifier, and an input stage, for example, a transducer; power is reflected. I would like to know why this occurs, and what happens to that reflected power?


What is the difference between network/link Speed and Bandwidth?

I did some research and some say they are same and interchangeable but some says they are different. What I understand is that Bandwidth is the amount of data carried while the Speed is the data carried at a certain rate. So, when we get Internet plan from our ISPs and they say that the speed would be, for example, 50Mbps. Is that Bandwidth or Speed? I am a little confused. Can anyone shed some light on it and make it clear? Thank you in advance


How to split string using split() using jquery

I want to split the 1&90 into 1 and 90 and assign in different variable.  $(document).on("click", "a[name='delete_user_journal']", function (event, element) {      var el = $(element);     event.preventDefault();     var j_id = $(this).attr("href");     alert(j_id); // 1&90 }


What's wrong with Arnold's scaling argument on jumping height?

The following question was put on hold:   It reminded me of an exercise (24a) on that exact topic in Arnold's "Mathematical Methods of Classical Mechanics". The solution he gives goes like that:     For a jump of height h one needs energy proportional to $L^3h$, and the work accomplished by muscular strength $F$ is proportional to $FL$. The force $F$ is proportional to $L^2$ (since the strength of the bones is proportional to their section). Therefore, $L^3h$~$L^2L$, i.e. the height of a jump does not depend on the size of the animal. In fact, a jerboa and a kangaroo can jump to approximately the same height.   The comments of the above question tended to dismiss that argument. What's wrong with it?  Addendum: It seems obvious that not all animals jump exactly to the same height, given their different physiologies/shapes. Some of them can't jump at all.  The question is to be understood in the following spirit: if we plotted jumping height vs animal size for a lot of different species, would there be a correlation? I don't mean there is no spread; I totally expect a big spread due to the other factors involved.  Second addendum: Some interesting points have been raised in comments and answers. I will accept an answer that incorporates: the domain of validity of Arnold's argument (or explain why it is never valid), the effect of air drag on very small jumpers and the impossibility of very large animals.   Bonus points for documenting the yet elusive jumping elephant and plotting jumping height vs size for different species ;)


I rescued Dexion and he immediately began attacking me.  Serana beat him down and we got out of the cave, but he was outside with us and began attacking again.  Serana beat him down again and I was able to fast travel to the Dawnguard hold.  He was inside and was attacking everyone.    I've tried:   changing his faction setting his hostility to 0 teleporting him outside the hold   One of the above console commands did something to him because now he's just standing still, but he's "busy", so I cannot interact with him.  I no longer have the auto save from before I rescued him, so I am going to need some console magic to fix this.


If $a \equiv b\pmod{m^2}$, then prove $ a \equiv b\pmod{m}$

How would I go about proving $$ a \equiv b\pmod{m}$$ given $$  a \equiv b\pmod{m^2}  $$ I suspected this was false, so I tried to find a counterexample using a , and there does not appear to be a counterexample for $m$ in (2, 16). What I have tried so far: $$  a \equiv b\pmod{m^2}  $$ $$ a = b + m^2k $$ $$ a - b = m^2k $$ $$ \sqrt{a - b} = \sqrt{m^2k} $$ Which would imply that $\sqrt{a-b} \equiv 0\pmod{m}$ assuming that $k$ is a perfect square. It feels like I'm barking up the wrong tree, however, and I'm not sure where to go from here.


Sum of an infinite series $(1 - \frac 12) + (\frac 12 - \frac 13) + \cdots$ - not geometric series?

I'm a bit confused as to this problem:  Consider the infinite series:  $$\left(1 - \frac 12\right) + \left(\frac 12 - \frac 13\right) + \left(\frac 13 - \frac 14\right) \cdots$$  a) Find the sum $S_n$ of the first $n$ terms.  b) Find the sum of this infinite series.  I can't get past part a) - or rather I should say I'm not sure how to do it anymore.  Because the problem asks for a sum of the infinite series, I'm assuming the series must be Geometric, so I tried to find the common ratio based on the formula  $$r = S_n / S_{n-1} = \frac{\frac 12 - \frac 13}{1 - \frac 12} = \frac 13$$  Which is fine, but when I check the ratio of the 3rd and the 2nd terms:  $$r = \frac{\frac 13 - \frac 14}{\frac 12 - \frac 13} =\frac 12$$  So the ratio isn't constant... I tried finding a common difference instead, but the difference between 2 consecutive terms wasn't constant either.  I feel like I must be doing something wrong or otherwise missing something, because looking at the problem, I notice that the terms given have a pattern:  $$\left(1 - \frac 12\right) + \left(\frac 12 - \frac 13\right) + \left(\frac 13 - \frac 14\right) + \cdots + \left(\frac 1n - \frac{1}{n+1}\right)$$  Which is reminiscent of the textbook's proof of the equation that yields the sum of the first $n$ terms of a geometric sequence, where every term besides $a_1$ and $a_n$ cancel out and yield  $$a_1 \times \frac{1 - r^n}{1 - r}.$$  But I don't know really know how to proceed at this point, since I can't find a common ratio or difference.


How to use prepared statements with Android sqlite?

so I am trying to understand how prepared statements are handled exactly? I have this code but I am unsure if it is using prepared statement or how to add prepared statements to it.  Code:  /*      * Creating a word      */     public long createword(DatabaseWords word) {         SQLiteDatabase db = this.getWritableDatabase();          ContentValues values = new ContentValues();         values.put(KEY_DICTIONARYID, word.get_dictionaryId());         values.put(KEY_WORD1, word.get_word1());         values.put(KEY_WORD2, word.get_word2());         values.put(KEY_WORD3, word.get_word3());         values.put(KEY_WORD4, word.get_word4());          // insert row         long word_id = db.insert(TABLE_WORDS, null, values);          return word_id;      }   How do I include prepared statements to A. make it go quicker, B. prevent attacks to the db


Show that, there are no integers $(m, n)$ such that, $m^2 + (m + 1)^2 = n^4 + (n + 1)^4$ . I really don't know how to approach this one i tried factorizing but it didn't seem to help , any hint would be appreciated .


c# compare two strings for a matching word (case insensitive)

I have a keyword Person. I have a list that has elements inside such as Person A,Apple, Person B,Pear , Person C ,Banana  I am trying to get the elements in the list that contains the keyword .  for(int i =0; i < list.items.count; i++){    if (keyword == list[i])       Console.WriteLine("Person") }   Im trying the code above and it does not seem to work. Can anyone help?


Find the singular points and the corresponding tangent lines of $X^4+Y^4-X^2Y^2$.    I get that the singular points are those of the form $(a,a)$ and $(a,-a)$. The corresponding tangent lines are $X=-a, Y=-a$ and $X=-a, Y=a$ respectively. Is this correct? Thanks.


auto-capitalise the output of a newcommand

How can I create a newcommand that automictically capitalises the first letter, when the command is used after a full stop (or question mark, exclamation mark, etc.)?  \newcommand{\tinycommand}{tiny command}   The desired input:  This is some text and a \tinycommand. This is some text. \tinycommand.   The desired result:  This is some text and a tiny command. This is some text. Tiny command.


Is there travel insurance for missed flights?

Our family will be going to Rome this November.  As in , I am worried about missing my return flight home.  Is there travel insurance that will help us find a return ticket home if that happens?  I'm talking about us missing a flight with no fault of the airline.  Like if the train breaks down or we get stuck in traffic.  This policy would need to buy us return tickets home and since there might not be a ticket available, I imagine it would have to be able to do some clever negotiating with the airline and hotels.  Does that exist?


I used to play this game on my PC ,but after a complete reboot of PC it won't launch the game anymore. When it is supposed to launch it, it sends me a crash report. I have no idea how to post it over here, so here you go, the whole copy of it:  ---- Minecraft Crash Report ---- // Sorry :(  Time: 29.10.16. 16.37 Description: Initializing game  org.lwjgl.LWJGLException: Pixel format not accelerated     at org.lwjgl.opengl.WindowsPeerInfo.nChoosePixelFormat(Native Method)     at org.lwjgl.opengl.WindowsPeerInfo.choosePixelFormat(WindowsPeerInfo.java:52)     at org.lwjgl.opengl.WindowsDisplay.createWindow(WindowsDisplay.java:247)     at org.lwjgl.opengl.Display.createWindow(Display.java:306)     at org.lwjgl.opengl.Display.create(Display.java:848)     at org.lwjgl.opengl.Display.create(Display.java:757)     at org.lwjgl.opengl.Display.create(Display.java:739)     at bcx.ap(SourceFile:598)     at bcx.an(SourceFile:434)     at bcx.a(SourceFile:381)     at net.minecraft.client.main.Main.main(SourceFile:124)   A detailed walkthrough of the error, its code path and all known details is as follows: ---------------------------------------------------------------------------------------  -- Head -- Thread: Client thread Stacktrace:     at org.lwjgl.opengl.WindowsPeerInfo.nChoosePixelFormat(Native Method)     at org.lwjgl.opengl.WindowsPeerInfo.choosePixelFormat(WindowsPeerInfo.java:52)     at org.lwjgl.opengl.WindowsDisplay.createWindow(WindowsDisplay.java:247)     at org.lwjgl.opengl.Display.createWindow(Display.java:306)     at org.lwjgl.opengl.Display.create(Display.java:848)     at org.lwjgl.opengl.Display.create(Display.java:757)     at org.lwjgl.opengl.Display.create(Display.java:739)     at bcx.ap(SourceFile:598)     at bcx.an(SourceFile:434)  -- Initialization -- Details: Stacktrace:     at bcx.a(SourceFile:381)     at net.minecraft.client.main.Main.main(SourceFile:124)  -- System Details -- Details:     Minecraft Version: 1.10.2     Operating System: Windows 7 (x86) version 6.1     Java Version: 1.8.0_111, Oracle Corporation     Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation     Memory: 80026872 bytes (76 MB) / 148910080 bytes (142 MB) up to 523501568 bytes (499 MB)     JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M     IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0     Launched Version: 1.10.2     LWJGL: 2.9.4     OpenGL: ~~ERROR~~ RuntimeException: No OpenGL context found in the current thread.     GL Caps:      Using VBOs: Yes     Is Modded: Probably not. Jar signature remains and client brand is untouched.     Type: Client (map_client.txt)  Resource Packs:  Current Language: ~~ERROR~~ NullPointerException: null Profiler Position: N/A (disabled) CPU: <unknown>   PLEASE someone try to answer to this, my knowledge of doing something on PC is complete 0.


I am trying clean up topology, and I have found an issue which I will have to do a TON work for this mesh.   I have a line of vertices I would like to quickly make straight. You can do this in the UV/Image editor by pressing W > Align X or Y.  Is there any possible way to achieve this is the 3D View?


Ubuntu 18.10 on Dell Inspiron 13 7000 AMD Ryzen7

Ubuntu 18.10 live usb will not boot on my Dell Inspiron 7375 13" 2-in-1 laptop. This is a Ryzen 7 machine with Vega graphics. I have ran and installed openSuse, KaOS, and presently running Fedora 28. The AMDGPU driver works for me on these other distros, but I don't think that's the issue. I miss using Ubuntu, as I am a long time user of Ubuntu and Kubuntu. Any help would be appreciated.   Update, this is what I see when I try to boot. Just repeats over and over.    watchdog: BUG: soft lockup CPU#0 stuck for 22s! [migration/0:12] watchdog: BUG: soft lockup CPU#1 stuck for 22s! [migration, etc for all 8 cores  Update!! I finally figured it out! When booting into the live usb, type "e" to edit the boot parameters. Arrow down to the line that starts with "linux", arrow over to where it says "quiet" and "splash". Remove "quiet", "splash". Then type, "noapic noacpi nosplash irqpoll", and voila, she boots right up.  Thanks to Linuxmint for this solution, aka, compatibility mode. Hope this helps others that may have this problem.


When does the word 'months' get an apostrophe?

Is it '12 month's remuneration', '12 months' remuneration' or '12 months remuneration'? New Oxford Style Manual says it does not get an apostrophe is not used in 'adjectival constructions' e.g. three months pregnant. Confused.


Say I have set up a few aliases for long bash commands:  alias test1='long-command-1' alias test2='long-command-2'   and so on. Is it possible to list all aliases currently defined (ideally with the command it is an alias for)? Is it possible to undefine (remove) an alias?


We're building a web-based platform where the main dashboard shows a table of data for users to view and analyze. As we're growing this tool, we seem to be adding more and more columns and are running out of horizontal space on smaller screen resolutions (we're seeing some data wrap). It is important to the user to view all columns at once, so column hiding is somewhat out of the question, as is horizontal scrolling (per the boss's request and because horizontal scrolling sucks anyways). I was wondering if anyone knew of a clever UI for tables with many columns.  EDIT  Below is a screen capture of the layout of the table. Unfortunately for security purposes I had to blur out the column titles. This example has rows with practically no data in them, but in use they will have lots of data that will expand wider than their respective column titles. In response to some of the answers, it is imperative that the user see all the columns, as they are all necessary to analyze the data to make certain decisions. All the data is numeric aside from the first three columns. Thanks again for any feedback.    Ok so I see that uploading this image doesn't really do it justice... it takes up the full width of the screen at 1680x1050 resolution (22") and as data fills in the columns, the left column w/the text shrinks down a bit.  EDIT 2 I just wanted to say thank you to everyone's awesome ideas. I can only select one answer, but a lot of your ideas have proven very useful and may end up in the final product. Thanks again!


Unable to get force:inputField or force:outputField to render inside other markup in Lightning Component when used in Lightning Experience

I've created a Lightning component to view key details for the Account and Contact lookups from a Case, like so:    The problem is, I have been unable to get field content to render when  using the <force:inputField/> or <force:outputField/> components when I place them inside the markup to style them as cards. I've used <ui:outputText/> as a workaround, but that means I don't get any of the built-in behaviors I would get with the <force:*Field/> components -- like Lightning styling, which means I have to manually do it using SLDS.  This displays the contact name as expected:  <aura:component implements="flexipage:availableForRecordHome,force:hasRecordId" access="global" controller="LightningCaseTestController">   <aura:handler name="init" value="{!this}" action="{!c.doInit}" />   <aura:attribute name="recordId" type="Id" />   <aura:attribute name="contact" type="Contact" default="{sobjectType: 'Contact'}"/>    <force:outputField value="{!v.contact.Name}"/>   <force:inputField value="{!v.contact.Name}"/>  </aura:component>   This does not:  <aura:component implements="flexipage:availableForRecordHome,force:hasRecordId" access="global" controller="LightningCaseTestController">   <aura:handler name="init" value="{!this}" action="{!c.doInit}" />   <aura:attribute name="recordId" type="Id" />   <aura:attribute name="contact" type="Contact" default="{sobjectType: 'Contact'}"/>    <article>     <force:outputField value="{!v.contact.Name}"/>     <force:inputField value="{!v.contact.Name}"/>   </article>  </aura:component>   Basically, it appears that as soon as any markup is placed around the <force:*Field/> tags -- even just a <div> -- they no longer render. Examples in Trailhead and other places all seem to use <ui:outputText/> or <ui:input*/>.  This seems like a lot of extra manual work. Am I missing something?  Update: it only fails when the component is included in a Lightning page -- such as the record detail page -- from Lightning App Builder. If I add it to a simple Lightning app, it works:  <aura:application >     <c:LightningCaseTest recordId="SOMECASEID" /> </aura:application>   So it appears to be a bug?


Can we call a Rest API method and retrieve more than 50,000 records in a Salesforce Environment?

I'm not sure how to phrase this question correctly, but the gist is that, an external party will access our Salesforce environment via REST Api and retrieve more than 50,000 account records. Now I know we can only query 50,000 records via SOQL and that we need to do pagination to get more. However, we're not developing a UI, we just want to retrieve account records in the Salesforce environment and we expect the return would be more than 50,000 records. Any help would be much appreciated. Thanks.


I have a document where I quiet often refer to source code element, such as class names, I wanted to format these strings differently, but at the beginning I didn't want to fiddle with various options I had, rather I defined my custom command as follows:  \providecommand{\inlinecode}[1]{\texttt{#1}}   Now my question is, what do you think is the best way to define \inlinecode? Note: I often use text with unescaped <, >, e.g., List<T>.   The \texttt looks fine to me, and works with <, >, but sometimes the words overflow the line. Is there any way to tell latex not to overflow the line, but rather "underflow" or insert more spaces between words, which seems to me as (maybe still ugly but) more acceptable than overflow? And is it possible to achieve it by only changing definition of my command, so I won't have to change the whole source?


Where should I continue after the third anime season?

I plan to read manga of The World God Only Knows.  I've watched up to and including season 3 of the anime. Which chapters do I need to start at to continue?


Verb forms for "any" and "none" — have or has?

That car is way better than any car any of us have/has ever driven.      None of us know/knows which direction Ron's house is (in).    I have two questions here.   In both the cases, are we to use the singular verb, or the plural? In the end of the second sentence, is using the preposition where it's been used, necessary? Would it be okay if it had no prepositions in it?


Before (dis)proof, how can you determine the conclusion of given collection of long complicated premises?

Source: p 287,   (2010 2 ed) by Henle, Garfield, Tymoczko.     [1.] Predicate is the reason we started on deductions. In Sentential, remember, we can verify that an argument is valid by using truth tables or the short-cut method. With Predicate, we have no such tool. We can show that an argument is invalid if we exhibit a universe in which the premises are true and the conclusion is false, but (until now) we have had no means of showing that an argument in Predicate is valid.    In the 2 Logic textbooks  read (the above and ), each exercise on deductions (e.g. the following) divulges the conclusion of an argument (whether or not valid). But without computers, for a given collection of > 10 long convoluted premises: What if the conclusion were concealed or tacit? How can you determine it yourself?   I am assuming that you must at least conjecture the conclusion, before attempting (dis)proof?


How is the bash subshell `sed` output to be put in the main shell environment variable

How to put the bash subshell sed output into the main/root shell environment variable ? it'll fail, v=`echo NO |tee >(sed 's/^/&YES/' )`  How's the true to solve it?


What kind of functions cannot be described by the Taylor series? Why is this?

It's true that I'm not familiar with too many exotic functions, but I don't understand why there exist functions that cannot be described by a Taylor series?  What makes it okay to describe any particular functions with such a series? Is there any difference for different number sets? In the case of complex numbers maybe?  Could somebody provide an example?


What's the meaning of "##" in a C++ macro?

What's the meaning of "##" in the following?  #define CC_SYNTHESIZE(varType, varName, funName)\ protected: varType varName;\ public: inline varType get##funName(void) const { return varName; }\ public: inline void set##funName(varType var){ varName = var; }


What is the difference between closure function and normal function in javascript?

CASE 1: function Test(name){    var privateName = name;    this.getName = function(){       return privateName;    } }  var name = new Test("unknown"); console.log(name.getName())  CASE 2: function getName(pName){     var name = pName;     return name; }  var name = getName("unknown") console.log(name)  It seems both are doing the same thing returning the name passed to the function. Then what is the difference between the two implementations? What are we trying to achieve in CASE 1?