Trying to use Threads to fill an array. Program seems to skip a lot of elements

I'm trying to set the elements of an array to be equal to the square root of their index using threads. I know this can be easily done without threads, but I am trying to learn about threading.  When I run this code, A lot of the elements do not change from the default value of 0. And I can't figure out why.  class Program {     static double[] array = new double[100000000];      static void Main()     {         int threadCount = 8;         Thread[] threads = new Thread[threadCount];          for (int i = 0; i < threadCount; i++)         {             threads[i] = new Thread(() => SquareRoot(i, threadCount));             threads[i].Start();         }         for (int i = 0; i < threadCount; i++)         {             threads[i].Join();         }     }      static void SquareRoot(int start, int incrementSize)     {         for (int i = start; i < array.Length; i += incrementSize)         {             array[i] = Math.Sqrt(i);         }     } }


How to find classes by annotation on classpath?

On startup of a spring-boot application I want to perform a scan for all @Entitiy classes on the classpath.  Moreover, I'd like to filter any entities with a @CustomAnnotation.  I want to create some kind of auto configuration, and use the package of any entities found in:  EntityManagerFactoryBuilder   .dataSource(ds)   .packages(getPackages()))   But I don't want to explicit define the package there the appropriate entities are to be found, but find them on startup. Is that possible at all?


for loop in python with decimal number as step

I want to make a for loop that looks like this:  for x in range(0, 1, 0.1):     print(x)   obviously it throws this error:      Traceback (most recent call last):     File "", line 1, in        for i in range(0, 1, 0.1):   TypeError: 'float' object cannot be interpreted as an integer   So it there a way in python 3.6 to make a for loop with floating point?


What type of spell let Snape and Voldemort fly in "Harry Potter and the Deathly Hallows"?

In the last book, Snape and Voldemort are seen to be able to fly, after Snape is pushed out of the window in the Hogwarts' classroom. Voldemort flies during his hunt for the owner of the elder wand. How are they able to fly? What is this spell which can enable you to fly, which is stated by the author? (not in Harry Potter Wikia)  I seem to remember there is one such spell known as the Wingardium Leviosa, which lets the person and/or object hit levitate in the air, but this wouldn't be counted as actually flying, just as Snape and Voldemort have done. Does J.K. Rowling ever answer this in any of her interviews?


Another way to say the max and min number

I've been writing a program and I often come across naming variables that store the maximum and minimum value in a set of data. Is there any word that means both the max and minimum values of something? Right now the only word I can think of describing this is "outlier" but I feel that implies that that particular set of data is much farther away from the other points and I simply feel there is a better word out there to use. Thanks for any suggestions in advance :)


I'm hoping to visit Japan in the next few years on holiday.  I would stay for almost the maximum tourism period, which for Uk Citizens is 3 months or so.  I have heard that law enforcement there is very strict indeed.  Evey day, I answer several online surveys that offer paymebts typically, and of up to £1.50 each or so.  It can sometimes be more, but only by a few pounds.  I do this all day long though, and as circumstances permits me.  Through various websites, I am able to be paid around £10-20 or just over per week for doing these, irregularly.  The payments can often be requested when I'm back home though.  I have travelled to Russia, USA and many other European countries, but I have never been questioned about doing it by any officials.  My question is, would I, or is there much likelihood to be found by law enforcement there, or if so, questioned or convicted for it as I would not have a working visa?  All of the surveys and market research I respond to are emailed to ne from companies online.  Mostly survey websites based in United Kingdom.  This is classed as self-employment usually.  I may be noticed as I often do this outdoors using a tablet device and in acoomodations too.


On RHEL 7, I am trying to add service postgresql permanently.  Without --permanent option, the command below runs well.  [root@sample services]# firewall-cmd --list-services dhcpv6-client http https ssh [root@sample services]# firewall-cmd --add-service=postgresql success [root@sample services]# firewall-cmd --list-services dhcpv6-client http https postgresql ssh [root@sample services]#   However, when using --permanent option, below error surfaces.  [root@sample services]# firewall-cmd --remove-service=postgresql success [root@sample services]# firewall-cmd --add-service=postgresql --permanent Error: INVALID_SERVICE: oracle   Why is the error mentioning 'oracle'? How do I actually allow 'postgresql' service permanently via firewall-cmd?


I am fairly new to Java and am in need of help with my If/Else statement. Basically I want to make it so that if the person types in n or no do one thing, or if the person puts in y or yes, do another thing, and if the person doesn't put in n, no, yes or y than do a different thing. But no matter what the user puts in, it acts as if they did not put in n, no, yes or y. How can I fix this?   This is my code so far:  public class Main  {  public static void main (String[] args)  {     Scanner userInputScanner = new Scanner(System.in);     String [] charName = {"John", "Bob", "Sam"};     Random random = new Random();     int charNameChoice = random.nextInt(charName.length);     System.out.println("Random char selected: " + charName[charNameChoice]);     System.out.println("Y N Question1");     System.out.println("You can input y, yes, n or no");     String questionOneAnswer = userInputScanner.nextLine();     if (questionOneAnswer == "n" || questionOneAnswer == "no")     {         System.out.println("I disagree");     }     else if (questionOneAnswer == "y" || questionOneAnswer == "yes")     {         System.out.println("I agree");     }     else     {         System.out.println("Invalid");     }   }  }


My Camera on my android tablet isn't letting me take any pictures. help?

The camera on my Android tablet doesn't let me take any pictures. It says Insert an SD card before using the camera.  I didnt need an SD card before. I put an SD card in and it still says the same thing!  Is there a solution to my problem that would help? I already tried the solution proposed in , but it didn't solve my problem.


Is it a good programming practice to use import static fields?

I declare some constant variables in my SQLiteOpenHelper class:  public static final String USERNAME = "user_name"; public static final String PASSWORD = "password";   In an Activity where I create SQL queries, I import these fields:  import com.mygame.ui.login.LoginInfoSQLiteOpenHelper.*;   Is this a good practice? Or the traditional way of referring to constants better?  LoginInfoSQLiteOpen.USERNAME


How do i solve this problem?  $\frac{-1}{3}|6−5x|+2<1$  so far I took the 2 to the other side, multiplied both sides by -3 to cancel out the -1/3  leaving me with $|6-5x|>3$  is this correct? by flipping the signs since i multiplied by a negative?but then what?


Operating System not found in 14.04.3 (32bit)

Need Help!! I downloaded the ubuntu ISO file from  for 32bit.  I have try 64 bit as well - Same problem.  Install in VMware Using Typical (Recommended) When I created the new virtual machine, in the page of choice the installer from disc image file (ISO). An error sign shows up:     Could not detect which operating system is in the disc image. You will   need to specify which operating system later.   I continue to click next and on the next page I choice the Guest operating system type for Linux and for Version type i choice Ubuntu. After finish the setup, I start the virtual machine. It show Operating system not found in the VM.


How to Stop Windows from Resetting Language Shortcut Config?

A consistent issue between all computers I have owned:  I speak a few languages and learning even more, so instead of using Windows + Space it's more convenient for me to go to Language->Spelling, Typing, and Keyboard Settings-> Advanced Keyboard Settings-> Language Bar Options, and set different shortcuts for each language.  The problem is, pretty much anytime I restart the device, or my computer goes to sleep, it gets rid of all the shortcuts except for Japanese and Chinese.   Some things to consider:   These computers have had separate accounts, and my brother who has similar needs experiences the same issue. I have also seen some cases around that have the same thing happen to them: all language keyboards are cleared out except for Japanese and Chinese. It might be because of their IMEs, but I also have Korean, which is still reset.


I have two tables: datess, deletess, sample  I wrote a query like this:  DELETE FROM sample WHERE sample_date_key IN (SELECT date_key FROM datess WHERE s_date BETWEEN '2015-02-18' and DATE'2015-02-25');   But I have 2 rows and two columns in deletess:  start_date  |  end_date ------------+---------- 2015-02-18  | 2015-02-18 2015-01-18  | 2015-01-18   I want to delete all the rows in sample with dates between start_date and end_date in deletess.  I tried the below code but got error:      ERROR:  more than one row returned by a subquery used as an expression   (SELECT date_key FROM datess WHERE s_date BETWEEN (SELECT start_date FROM deletess) AND (SELECT end_date FROM deletess);   I appreciate any help. Thanks!


According to , $@ and $* do pretty much the same thing:   The $@ holds list of all arguments passed to the script.  The $* holds list of all arguments passed to the script.   After searching all the top hits in google, I'm not able to find any explanation why there would be 2 seemingly duplicate syntaxes.   They appear to work the same in my scripts.   cat foo.sh #!/bin/bash echo The parameters passed in are $@ echo The parameters passed in are $*  ./foo.sh herp derp The parameters passed in are herp derp The parameters passed in are herp derp    Is one preferred over the other?  Why are there 2 builtin variables to do the exact same thing?     Additional sources


Ubuntu Software only lists installed programs

DISCLAIMER: I'm brand new to Ubuntu, and I have zero coding experience, so please keep any answers in layman's terms.  I was browsing the Ubuntu Software store thingy (Software Center? Ubuntu Software? wtf is it called) to look for programs to download. When I go to browse, however, it only lists programs I have installed. I've tried to look up answers to this issue, but I can't understand any of the solutions posted since it's almost all in code or in extremely technical jargon I just don't understand. Could someone that knows their stuff please help a newbie out? I don't even have any idea where to start, so please explain to me what I need to do.  Nothing is missing when I go into the Ubuntu Software. It's only when I go to browse the different categories where it only shows what I have installed. I can still utilize the search feature to find specific programs, but as you can imagine I can't get all that far using just that if I don't know what's out there.  I've restarted my computer and it didn't do anything to fix it.


I have used regex to test for the email input. It does give an alert when a wrong email (for eg without an @ or .com) is submitted but when I press ok for the alert, it still posts the email to the email address that is am directed to the page send_msg.php when it should not.. I am quite new to Javascript and PHP so I am still learning.. I know that the if clause should follow an else but I don't know how to make it post the email if it is true. And can how I make it just display a message below the email input field instead of making it raise an alert?


I want to write inline mysql code with minted. However, there is an error Undefined control sequence \mintinline.  This is MWE:  \documentclass[a4paper,oneside, 12pt]{memoir} % подешавање српског језика и ћирилице \usepackage{fontspec} \usepackage{polyglossia} \setmainlanguage[Script=Cyrillic]{serbian} \setmainfont{Times New Roman}  \newfontfamily\cyrillicfont{Times New Roman} \let\cyrillicfonttt\ttfamily  \usepackage{graphicx} \usepackage{threeparttable} \usepackage{mathrsfs,amsmath,amssymb,amsthm,upgreek} \usepackage{pbox} \usepackage{algorithm} \usepackage{algpseudocode} \usepackage{multirow} \usepackage{booktabs} \usepackage{layouts} \usepackage[colorlinks=true,linkcolor=blue, citecolor=blue, urlcolor=blue]{hyperref} \usepackage{etoolbox} \usepackage{placeins} \usepackage{tcolorbox} \tcbuselibrary{minted} \usepackage[framemethod=tikz]{mdframed} \usepackage{lipsum} \usepackage{minted}  \newtcblisting{sql}[1][]{%   colback=white,   listing only,   minted options={     fontsize=\small   },     minted language=mysql,   #1 }  \usemintedstyle{tango}  \begin{document}  \begin{sql} SELECT * FROM Korisnik; \end{sql}  Koristimo tabelu \mintinline{mysql}{Korisnik}.  \end{document}   If I delete the line with \mintinline, everything else works.


Why do elliptic curves have group structures? Why can't an ellipse or a circle have a group structure? I am a beginner to cryptography. I am curious about the algebraic intuitions behind the group structures on the elliptic curves.


I created a user in terminal by  useradd xyz   I'm able to log in from the terminal but not in the GUI.  What is wrong?


Conservation of energy of a rotating body

The famous example of acrobats shrinking their bodies to increase their rotation speed is well known. Where does the energy to increase the speed of their rotation comes from?


Equivalent of local idiom "The potter drinks from a broken jar"

There's an idiom in a native language which literally means "The potter drinks from a broken jar".  i.e. a potter will not spend a lot of time making a beautiful jar for himself to drink from, he uses a poor quality one or one that's been broken for himself.  It means that someone who is good at a profession usually sells his high quality work instead of using them for himself and doesn't use them for his own benefit.  Is there an English idiom that conveys the same meaning?  UPDATE  FYI, I was interested in this idiom because  consisted of 1 page displaying my email address and saying "We'll have more soon!" during my many years of web development and making websites for others.


Is there a page that allows mere mortals to know who actually works for Stack Exchange?

So, there are mods, and there are Mods - by which 1 mean the 101 diamonds / actual Stack Exchange employees who have access to the devs, etc.  By playing around regular input and activity on the various sites, I think I know many of the actual SE staff (Shog, Adam Lear, Jon Ericson, Marc Gravell, etc.), but is there a page where I can see all of them?  In some ways it would be really nice just to be able to see their interests and be able to quickly differentiate, say, Shog9's input from <insert your least favorite troll here>.  Ideally, this would be a 'flair page' meaning that the staff directory would show the name, function, and reputation of each individual on staff.    I realize this may be mere voyuerism on my part, but it is still nice to know the players. More importantly, if someone hits the 'contact us' link, it would be nice to know who is answering. (Yes, it's probably Adam or Shog, but again...)


I have more than 500 systems running ubuntu 10.04, ubuntu 10.10 and ubuntu 11.04. It is difficult for us to install new packages to these machines from internet, because of the high bandwidth usage. I am planning to set up an apt-cacher server, such that it should install packages from a local machine, instead of installing packages from the internet. Can anyone give me a neat solution please? Thanks in advance. Error in server configuration: root@karthick:~# sudo /usr/share/apt-cacher/apt-cacher-import.pl /var/cache/apt/archives Importing: acl_2.2.49-3_i386.deb Failed to rename acl_2.2.49-3_i386.deb. Try read-only (-r) or symlink (-s) options. at /usr/share/apt-cacher/apt-cacher-import.pl line 154.  Error in client on installing packages  Can anyone sort out pls?


What is the file location of GNOME favorites?

I want to directly inspect the contents of my GNOME favorites bar. What is the file location for this bar?  (Similar questions focus on creating custom .desktop files in ~/.local/share/applications, setting the WM_CLASS, and pinning the running application. I am looking for direct access to the stored data.)


is the group cyclic, if Normal Subgroup and Quotient group are cyclic.

Prove or disprove that if $H$ is a normal subgroup of a group $G$ such that $H$ and $\frac{G}{H}$ are cyclic, then $G$ is cyclic.   I am not sure if the above question has any mistake.   I know examples where $\frac{G}{H}$ is cyclic, but $G$ is not cyclic. It is $$G = S_3 = \{ I, (12),(23),(31), (123), (132) \}$$ and $$H = \{I,(123),(132)\}$$ H is a normal subgroup of G.  $\frac{G}{H}$ is cyclic since order of G/H is 2 and every group of prime order is cyclic.   But G is not cyclic.   I am doing graduation course.   Please give me an example to disprove or proof for above problem.


Javascript -- reliable to use numbers as integers?

Why is it apparently safe to use numbers as integers in Javascript? What I mean is that a loop such as the one below is generally "trusted" to run the expected number of times even though the final loop requires an exact compare of (10000 == 10000) when these two values are floats and not ints. Is there some sort of built-in rounding feature that makes this safe and reliable -- or is this horrible and untrustworthy coding? Thanks.  --edit--  It is interesting that there is a declared safe integer range. I was not aware of . We all know the standard whine that 2 + 2 = 3.9999. I note that MAX_SAFE_INTEGER is listed as ECMAScript-6 so does this imply that IEEE-754 does not actually mention a safe integer range?    var cnt = 0; for (var i=0 ; i<=10000 ; i++){   // loop 10001 times   cnt++; } alert('cnt = '+ cnt);


An integer $n$, such that $nx = 0$, where $x$ belongs to the quotient group $\Bbb Q/\Bbb Z$

Well, first, let $x$ be an element of the factor group $\mathbb Q/\mathbb Z$ ($\mathbb Q$ and $\mathbb Z$ are the additive groups, by the way).  Now, how do we find an integer n, such that, $nx = 0$, $n \ge 0$?  I managed to figure out that each x can be uniquely represented as $x= \dfrac{a}{b} + \mathbb Z$ for $0 \le a< b < 1 , \; \text{gcd}(a,b)=1$.  Now, I've considered that perhaps, I'm not understanding the question. When $nx = 0$, I assume it means, essentially the same thing as $nx =\mathbb Z$, which is the identity element of Q/Z, right?  The obvious choice for $n$ would be a multiple of $b$.  Trying $n=b$, we have, $nx = a + b \mathbb Z $, but this is just a single coset of $b \mathbb Z$. A particular equivalence class $(a \mod b)$.  Which brings me to another question:  Consider $x+x = \dfrac{a}{b}+ \mathbb Z + \dfrac{a}{b} + \mathbb Z = 2 \dfrac{a}{b}+ \mathbb Z $,  But, $2x = \frac{2a}{b} + 2 \mathbb Z $.  I know, I must have slipped with the permissible algebra, but somehow, I just seem to be unable to reconcile the $2$, or choose between them.  Which of these is correct? (Perhaps the first one, given that addition is actually the operation of $\mathbb Q/\mathbb Z$?)  Also, how would I go about finding the integer $n$? I would really appreciate it if, instead of actually finding $n$, someone could hand me a pointer in the right direction, and let me wrangle it myself.  Thank You!


How and why should users vote on answers?  This explains how to accept an answer:


I have installed Ubuntu 18.04.1 LTS, and I need to add some routes. Which command shall I use? ifup was deprecated?


Vertical spaces between lines in cases environment

\documentclass{article} \usepackage{amsmath} \begin{document} \begin{equation*}   X_i =    \begin{cases}     \left[\begin{smallmatrix}       0 \\ 1 \\ 2     \end{smallmatrix}\right]     &     \text{if $i$ is even;}     \\     \left[\begin{smallmatrix}       2 \\ 1 \\ 0     \end{smallmatrix}\right]     &     \text{otherwise.}   \end{cases} \end{equation*} \end{document}   This is the LaTeX code that I wrote based on a cases environment. There's no space between the matrices on the right. What's the best way to add some vertical spaces to separate them?    p.s. This is a simplified form of my original writing, so I cannot just accept suggestions like 'use a matrix transpose to transform the column vector into a row vector.'


Make Ctrl-Alt-T focus existing terminal window if there is no active process in it

I want Ctrl-Alt-T to focus (bring back to front) an existing terminal window if there is no running process in it (e.g. top). If there is no terminal window without a running process, a new window should be opened. Is that possible?  Edit: It's not a duplicate. The further going idea is the following: I do not want to get a terminal where I can not execute a command right now because it's busy (a process is running in it, e.g top). So my wish was to get only a already opened terminal if there is no process in it.


can an IP be mapped to another IP in windows?

Can I map 146.112.61.106 IP address to my 127.0.0.1 adress ?  so when I type 146.112.61.106 I got redirected to 127.0.0.1 ? (some netsh command maybe ?)


Below is the type of texture I wish to generate using Blender's node system.    Thus far, I have tried using a mixture of Blender's base textures, noise, magic, voronoi etc. I have attempted to combine them, modifying with various math operations, colour ramps, distorting them with vector inputs (), yet, can't seem to get close to what I desire.  I would greatly appreciate a node setup that would enable me to achieve said looking texture. Cheers.  EDIT  Since posting this question, I experimented with the voronoi cracks node () to try and reproduce my desired texture, it was also ever so kindly suggested to me by, Duarte Farrajota Ramos.  Granted, this is close, but not the same as what I am hoping to achieve. The voronoi cracks produces an image with pointed corners, for lack of a better word, whereas in what I want to produce has rounded edges. Additionally, the Voronoi cracks produces shapes of vastly different sizes, my desired outcome, however; produces shapes that are roughly the same size as one another, with minimal differences in size.


Java Angle Math: Calculate how near the player looks to an entity

I am programming a Minecraft Bukkit plugin and need a way to calculate an input number from 0 to 360 for displaying a custom compass / radar. So if the player directly looks at the object (shouldn't handle viewing height or position height), this number would be 0 and if the player's back is looking on the object it would be 180.  I already successfully calculated both numbers I guess I need:   The absolute looking angle of the player. Is 0 when the player looks in north direction and 180 in south direction. The location angle between the player's position and the object's position. Using Math.atan2 to get the angle between [X, Z] of these locations.   Both values seem to be calculated correctly. But I can't find out what to do to get the number I described at first. Tried substraction, addition. Any ideas?


FileProvider.getUriForFile returns null object reference

FileProvider.getUriForFile is returning a nullobject reference and I have no idea why. This worked before. The following error is what I get. I also added my code below the error.  Process: com.example.joche.mywarranty, PID: 2522                                                                         java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.XmlResourceParser android.content.pm.ProviderInfo.loadXmlMetaData(android.content.pm.PackageManager, java.lang.String)' on a null object reference                                                                             at android.support.v4.content.FileProvider.parsePathStrategy(FileProvider.java:584)                                                                             at android.support.v4.content.FileProvider.getPathStrategy(FileProvider.java:558)                                                                             at android.support.v4.content.FileProvider.getUriForFile(FileProvider.java:400)                                                                             at com.example.joche.mywarranty.InputScreen$2.onClick(InputScreen.java:74)                                                                             at android.view.View.performClick(View.java:5610)                                                                             at android.view.View$PerformClick.run(View.java:22265)                                                                             at android.os.Handler.handleCallback(Handler.java:751)                                                                             at android.os.Handler.dispatchMessage(Handler.java:95)                                                                             at android.os.Looper.loop(Looper.java:154)                                                                             at android.app.ActivityThread.main(ActivityThread.java:6077)                                                                             at java.lang.reflect.Method.invoke(Native Method)                                                                             at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866)                                                                             at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:756)   Code:  imageUri = FileProvider.getUriForFile(context, context.getApplicationContext().getPackageName() + ".my.package.inputName.provider", new File(fileinputName));   AndroidManifest.xml file:  <provider         android:name=".GenericFileProvider"         android:authorities="${applicationId}.my.package.name.provider"         android:exported="false"         android:grantUriPermissions="true">         <meta-data             android:name="android.support.FILE_PROVIDER_PATHS"             android:resource="@xml/provider_paths"/>     </provider>   And ofcours the xml file with the path:  <?xml version="1.0" encoding="utf-8"?><paths xmlns:android="http://schemas.android.com/apk/res/android"> <external-path name="my_images" path="."/></paths>


I wonder, what's the difference between I'm finished and I finished (or even I've finished)?  To be more specific:  I'm given = someone gives something to me  I'm told = someone tells something to me  I'm finished = NOT someone makes me finish BUT  I have finished doing something.  Why?


How to change mouse pointer size and appearance in GNOME (18.04)?

I want to change the appearance (size, shape and color) of the mouse pointer.  What options are available for me?


Is there a way to Download all notes/attachments from a Salesforce Opportunity?

I have found it time comsuming to click into each note/attachement and click save to a certain folder.  Is there a tool that would allow me to pull all attachments from an opportunity to a folder on my desktop?


PDO Syntax error on a simple select all statement

EDIT: Inquiry already answered. Thanks, guys!  I realize this is probably the dumbest question ever & I'm likely missing something, but I'm absolutely stumped as to what causes this error message:     Uncaught exception 'PDOException' with message 'SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''index'' at line 1' in G:\server\www\mysite\engine\database.class.main.php on line 66   And here's the code that causes it:  // Åpne et nytt PDO objekt.         try {             $pdo = new PDO('mysql:host='. $dbhost. ';dbname='.$db, $usr, $pass);             $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);         } catch (Exception $e) {             die("Oh noes! There's an error in the query!"); // Dummy error msg.         }                     // Forbered forespørselen.         $row = $pdo->prepare('SELECT * FROM ?');         $ret = array();          // Så utfør forespørselen.         if($row->execute(array($page))) {              $result = $row->fetch(PDO::FETCH_ASSOC);             // Om forespørselen ble fullført uten feil, parsér data.             while($data = $row->fetchAll(PDO::FETCH_ASSOC))             {                 $ret = array_merge($ret, array($data['page_key'] => $data['content']));             }                     }   I recognize that parts of it are redundant and repeated, the code is very much work in progress. But the SQL statement isn't exactly advanced, it's just supposed to get everything from the table (which is the variable $page -- which is defined in the function).  Obviously I'm missing something, since it seems that the $page variable (which is "index") is causing the error, but I can't identify why. Any takers? I'd really appreciate the help!


"We" when I mean "I" or should I say "the author"?

I am currently working on my thesis and facing the problem of choosing between "I", "We" or "the author" when I want to talk about things I defined, decided etc. I am the only author of my thesis, but using "I" is not very common, is it? I saw quite a lot of work of single-authors that used "We" when referencing to themselves.  "The author" seems nicer to me, but it is not common?  Any recommendations or remarks?


Regular expression matching a given structure

I need to generate a regex to match any string with this structure:  {"anyWord"}{"aSpace"}{"-"}{"anyLetter"}   How can I do it?  Thanks     EDIT   I have tried:     string txt="print -c";    string re1="((?:[a-z][a-z]+))";   // Word 1    Regex r = new Regex(re1,RegexOptions.IgnoreCase|RegexOptions.Singleline);   Match m = r.Match(txt);   if (m.Success)   {         String word1=m.Groups[1].ToString();         Console.Write("("+word1.ToString()+")"+"\n");   }   Console.ReadLine();   but this only matches the word "print"


How to describe the feeling you get when something exceedingly irritating, irritates you?

Got extremely annoyed today. But that's not the word I was looking for.  I had to deliver a case of bottled water to some friends living in another dorm in our college.  I have to tell you, the sound of tight plastic rubbing against tight plastic is never a pleasant experience.  In any case, I had trouble describing the moment to my fellow friends, and they in turn had no idea how to describe it.  You know, the reaction to nails on a chalkboard, or something like that.


I want to show that $\text{Aut}(\mathbb{Z}_p)$ is isomorphic to $\mathbb{Z}_{p-1}$.   The group $\mathbb{Z}_p$ is cylcic and is generated by one element. The possible generators are $\{1,2,\dots , p-1\}$.   Each automorphism maps each of the elements of the set $\{1,2,\dots , p-1\}$ to one of the elements $\{1,2,\dots , p-1\}$.   So, we have the function $f_m(x)=mx\pmod p, \ 1\leq m\leq p-1$, right?   To show that $\text{Aut}(\mathbb{Z}_p)$ is isomorphic to $\mathbb{Z}_{p-1}$ do we define the function $$h:\text{Aut}(\mathbb{Z}_p)\rightarrow \mathbb{Z}_{p-1} \text{ with } \\ f_m\mapsto (m-1)\pmod {p-1} , \ 1\leq m\leq p-1$$ ?


Drag and drop video into OR drag and drop video in to

Which is more correct?  I’ve created a web page that you can just drag and drop the videos in to:  http://...  OR  I’ve created a web page that you can just drag and drop the videos into:  http://...


I've a simple code as below and it returns false when I have a space after "N/A" string.  String a = "N/A "; if((a.trim())=="N/A") {  System.out.println("true"); } else{  System.out.println("false"); }   if I remove the space as "N/A" then it returns true. What am I missing here. I know I'm making a silly mistake couldn't figure it out.  Thanks in advance.


There's any way to change it directly by Python, or there's any way to set by Python what node image is the active to display in viewport (Textured) and bake?


What is the planetary leveling path in SWTOR?

A friend and I are starting new characters.  which planet each class starts on, but we were wondering what happens after that.  Do the higher-level planets continue to cater to the same pairs of classes? Is there a point where all four classes meet up, or the classes swap which planets they have quests on?  Which planets have story quests for which classes?


Transferring files over home network WiFi

I've got 2 PCs with Linux distributions installed (one has Ubuntu 17.04 the other Mint 17.3) and I'd like to know how to transfer files between one another over my WiFi-network.   I would like to do that without having to install programs or using GUIs;  I want to use the terminal.


I know this question has been asked before, but I cannot find a solution to the issue of combo boxes. I have the following code:  ... JComboBox startingCombo = new JComboBox(); startingCombo.setModel(new DefaultComboBoxModel(new String[] {"USD", "EUR", "GBP"})); ...   I get an error when running from commandline:  Note: ConverterFrame.java uses unchecked or unsafe operations. Note: Recompile with -Xlint:unchecked for details.  When I do recompile with -Xlink:Unchecked I receive several of the following errors:  ConverterFrame.java:88: warning: [unchecked] unchecked call to DefaultComboBoxModel(E[]) as a member of the raw type DefaultComboBoxModel  This line then points to "new" on the second line in the code provided. I understand that I need to add an object type, but I am unsure where to add it and how.


Calculate expectation of a geometric random variable

When you download a file from a website, the file gets corrupted with probability 0.8. What is the expected number of downloads to get an uncorrupted file?  I have no idea how to do this. I only know the probability that a file isn't corrupted should be 0.2, but how do I get the expectation? Can anyone help me?


Ubuntu was too slow on my computer and Arch installation had many problems too. Which distro do you recommend to me that's lightweight as well as easy to install?


Batch Apex stateful member variable behavior in test class

Are stateful member variable of Batch Apex class maintain state after finish method when accessed in a test method. e.g.   global  class SampleBatch implements      Database.Batchable<SObject>,Database.Stateful {      global integer count;     global SampleBatch (){count =0;}      //START     global Database.QueryLocator start(Database.BatchableContext BC) {                  return Database.getQueryLocator(queryString);                      }          //EXECUTE      global void execute (Database.BatchableContext BC,List<sObject> scope){      count++;     }     //FINISH     global void finish(Database.BatchableContext BC){     }   }   When I try to access count variable in Apex Test Class it gives me value as 0, is it expected behavior?


Proof by induction that recursive function $\text{take}$ satisfies $\text{take}(n) = 100 - 2n$

I'm sick and tired off posting threads about induction... I just can't seem to get it, I need someone to give me a detailed explanation and treat me like a 5 year old, literally. I'm wasting a lot of time trying to revise one topic, and getting nowhere... I just don't understand :O  Here's an attempt :     Base case take(0) = 100 - (2*0) = 100 therefore it holds  Assume n=k holds take(k) = 100-(2*k)  prove take(k+1) = 100-(2*k+1)  take(k+1) = take(k)100-2k+1 take(k+2) = ...


When does a pursuer in a chase make a check to notice my sudden illusory hiding place?

According to , if I am being chased, round a corner and create an illusory 5×5 crate via Minor Illusion (and they do not see me cast it) I can successfully hide behind it to elude my pursuer.    What's not clear is whether and when my pursuer would be able to make an Investigation (Intelligence) check to penetrate my illusion. What would trigger their Intelligence (Investigation) check against the crate? What if they just kept running? Does a pursuer investigate everything they come across during a chase?


What would you call the husband of a widow?

I'm confused as I've been googling a bit and have seen "dead husband", "former husband", ... and even "ex-husband"...  So what would you use for ______ in polite conversation:     The ______ of the woman in the big house down the street must've liked his gadgets a lot!   and     I like working in your garden because your ______ had all the tools I need.   I'm looking for one (or maybe two?) words that politely provide context.


How do i do this in Ubuntu 19.4 ? Is there an application or command I can do  Looked around but no luck  Update: Found it by using " dmidecode -t 2 " ()


How to remove icons/shortcuts from Unity menu?

I have installed Chromium and Tweet Deck on it (trough Chrome Store), now I uninstalled Tweet Deck and after that Chromium, the problem is, when I installed Tweet Deck it asked me if I want to create a shortcut to it and I chose YES. Now that both are uninstalled the Tweet Deck icon still appears on Unity Menu over Internet.    I tried to remove the icon from the menu but I can't figure out how to do this. It should be a simple thing to do, but is giving me headaches :P  What I have to do to remove the shortcut and possible junk files from Chromium?  Also my Ubuntu version is 11.10 x64.  (Sorry if I write something wrong)


In the book "Topology" by James Munkres we define topology on a set $X$ like the following(page 76):  $\mathscr T$ is a topology on $X$ if:   $\emptyset,X\in\mathscr T$ $T\subset\mathscr T\implies\bigcup T\in\mathscr T$ $T\subset\mathscr T\land T\mbox{ is finite}\implies \bigcap T\in\mathscr T$   Why does the third property have the fact that $T$ is finite? What does it gives us?


Are the following expressions grammatically correct? If not, how should I correct each?   Giving 10 dollars to the store clerk:    Can I get some change in quarters? Can I get some quarters in exchange? Can you make change for one dollar into quarters? Can you break up one dollar into quarters? Can you exchange one dollar for quarters?


Allow Question Votes to count for tag synonym suggestions

NOTE:  is a request for total rep to unlock synonym suggesting.    This is not the same feature request.  This is a request to have Question Votes count toward the synonym suggestion total (rather than just answer votes).   I ask a lot of questions.  Like any good question asker, I research my question before asking it.  (However, I don't so so much research that I am ready to jump in and start answering questions.)    When I finally get around to asking my question, I frequently note that the phrase that is most commonly used to refer to a topic is not a tag.  After some searching, I find the right tag and I think "I would like to help out the next asker by putting a synonym on this tag".    But even if my questions get some up-votes, I can't help out like this.  It seems a bit backwards to me to have the answerers being the only ones who can suggest synonyms.  The anwerers KNOW their tag(s).  They don't need any synonyms (so they are less likely to suggest them).  It is the question asker that needs the synonym (so that they can get their question on the right tag).  Because the asker needs the synonym, they are the most likely to identify a missing one.  So, I would like to suggest this feature request:   Allow askers with X number of question up-votes in a tag (or just # of questions asked) to SUGGEST synonyms.   Don't allow them to vote on synonyms, because they are not the authority (like the answerers are).


How can I format multiple tables to be in proportion?

I'm trying to create an Appendix of SPSS tables in APA6 (12 pt) format. The issue is that some of the tables are greater than the width of the page. Any way I can think of to shrink them scales them down such that the text size is different in each table, which looks messy and is hard to read. I've tried adjustbox around 2 tables but they end up next to each other, and I've since read adjustbox isn't good for tables. I've tried to play around with xltabular, tabular*, tabularx but I haven't been able to make them work for my scenario, and I think the solution is probably beyond me. If anyone could show me how to do this it would be a huge help. \usepackage[utf8]{inputenc} \usepackage{adjustbox}   \begin{document}  \section{Appendix}   \begin{table}[htbp] \begin{tabular}{llllll} \toprule                      & Colour & N  & Mean   & Std. Deviation & Std. Error Mean \\                      \midrule   Attractive average & Grey         & 26 & 5.2051 & 1.47897        & .29005          \\                      & Red        & 17 & 5.1569 & 2.00734        & .48685          \\                      \bottomrule       \end{tabular} \end{table}  \bigskip \begin{table}[!] \textwidth \begin{tabular}{0}{lllllllllll} \toprule  & \multicolumn{2}{c}{Levene's Test for Equality of Variances} & \multicolumn{7}{c}{t-test for Equality of Means} \\ & F  & Sig. & t & df   & Sig. (2-tailed) & MD & Std. ED & \multicolumn{2}{c}{95\% CI of the Difference} \\      &   &  &    &      &      &      &  & Lower & Upper    \\ \midrule   Attractive average & Equal variances assumed     & 5.856 & .020    & .091 & 41 & .928 & .04827& .53172 & -1.02557 & 1.12210 \\  & Equal variances not assumed   &       &   & .085 & 27.182          & .933 & .04827 & .56670 & -1.11415 & 1.21068 \\  \bottomrule \end{tabular} \end{table}   \begin{adjustbox}{width=\textwidth} \begin{tabular}{l l l l l l l l l l l } \toprule  & \multicolumn{2}{c}{Levene's Test for Equality of Variances} & \multicolumn{7}{c}{t-test for Equality of Means} \\ & F  & Sig. & t & df   & Sig. (2-tailed) & MD & Std. ED & \multicolumn{2}{c}{95\% CI of the Difference} \\      &   &  &    &      &      &      &  & Lower & Upper    \\ \midrule   Attractive average & Equal variances assumed     & 5.856 & .020    & .091 & 41 & .928 & .04827& .53172 & -1.02557 & 1.12210 \\  & Equal variances not assumed   &       &   & .085 & 27.182          & .933 & .04827 & .56670 & -1.11415 & 1.21068 \\  \bottomrule \end{tabular}  \end{adjustbox}  \end{document}```


How to get the complete and exact list of mounted filesystems in Linux?

I usually use mount to check which filesystems are mounted. I also know there is some connection between mount and /etc/mtab but I'm not sure about the details. After reading  I get more confused.  My question is: How to get the most precise list of mounted filesystems? Should I just use mount, or read the contents of /etc/mtab, or contents of /proc/mounts? What would give the most trustworthy result?


Is a question deleted automatically once the downvote threshold has been met?

I recently asked a  in the wrong place (which has since been closed), and as a result my reputation has suffered a bombardment of downvotes. Ok, oops, wrong place, but now I cant even delete the question:  Of course I understand that irrelevant material should be moved, deleted or migrated, but since there was an answer to this question I am not able to do any of this. It seems there is a threshold of downvotes required for a post to be deleted. Currently my question requires one more downvote for this threshold to be met, but I ask, then what happens? Is a post deleted automatically once this threshold has been met? What about the answer that someone tool the time to write? Is there any recourse I can take to make this right, or do I have to watch my reputation drain from a simple mistake of where to post? I have flagged the question to either be moved to , or to be deleted but so far nothing has changed, other than my reputation going down.


What does this line mean in C# r => r.Item1?

r => r.Item1 == dFName  Its part of this line  dFName = PropertyUtil.GetName<kUpdate>(r => r.Resolution); fld2Lup = map.DTField2LookupMap[domType].First(r => r.Item1 == dFName );


After El Capitan upgrade synch does not work on texshop

I have installed el Capitan on mac. After reinstalling TeX and TeXshop synch doesn't work. How can I fix this?


Let $f$ be increasing and $x_1 < \dotsb < x_n$ in $[a,b]$. Show that $\sum_{i=1}^n o(f,x_i) < f(b)-f(a)$, where $o$ is the oscillation.

Let $f$ be increasing on $[a,b]$, take points $x_1 < \dotsb < x_n$ in $[a,b]$. I am trying to show that $\sum_{i=1}^n o(f,x_i) < f(b)-f(a)$ where $o(f,x_i) $ is the  of the function at $x_i$.  Here is what I have done: for any $\delta$, $$M(x_i,f,\delta)-m(x_i,f,\delta)\le f(\min(x_i+\delta,b))-f(\max(x_i+\delta,a))$$ where $M(a,f,\delta)$ is $\sup \{f(x)\}$ for $x$ in a $\delta$-neighborhood of $a$, and $m$ is the infimum. The oscillation is the limit of the difference as $\delta \to 0$. I have an upper bound for the oscillation, but I can't find a way to make the terms cancel out when I add them.


Prove by induction that $(x+1)^n - nx - 1$ is divisible by $x^2$

Basis step has already been completed. I've started off with the inductive step as just $n=k+1$, trying to involve $f(k)$ into it so that the left over parts can be deducible to be divisible by $x^2$ but getting stuck on this inductive step.


Bug: biblatex can not deal name prefix like "van der ", Miktex updated on 2016.01.16

Firstly, hello everyone. I am new here : )  I am writing my phd thesis using MikTeX + TeXnicCenter and everything goes well, until I have updated MikTeX today.  My Problem:  The program gives an error message to the "same old" command:  \printbibliography[prefixnumbers={},notkeyword={Eigene}, notkeyword={Datenblatt}, title={Fremdliteratur}, heading=subbibliography]   The error message looks like this:  Undefined control sequence. <argument> ...nameprefix {van~der}\isdot }\ifprefchar    Investigation  I have found out that this error comes from the name prefix "van der". If I write them together without space in *.bib file and compile it, it works again.  What's the best way to fix this or work around it? Is it a bug?


I am looking for a simple command in GNU/Linux to count all files in a directory beginning with pa.   I have already executed the command to show all the files beginning with pa which I used find /etc/file/magic -name "pa*" and it shows up 4.  However, I need a command to actually count this.


How to cite a github repository that I used for data collection (research paper)

I am working on a research paper where I work with large amounts of data. The data was collected using a python code that I found on someone's Github repository. I was wondering how I would go about citing the repository in an apa style.


wrapper class and normal string declaration gives same output?

I tried below given examples    String s=new String("cat");     String s1=new String("cat");     System.out.println(s==s1);     System.out.println(s.equals(s1));   this gives me output false and true.     String s="cat"; String s1="cat"; System.out.println(s==s1); System.out.println(s.equals(s1));   in this case the output of both is true may i know the difference between both i heard both wrapper class and normal string declaration gives same output


Weird behaviour between double quote and single quote in java

Just comparing some behaviors accross different languages and in java (java 8) I have tried something and I got weird results: here I iterate over a small String array, and display the iterator along with the value (nothing fancy, we agree...). however when I change in the sysout concatenation between single quote ' ' and double quote " " the behavior is completely different. 1- displays the end result of the iteration (3 as I increment through the loop) and it seems that it calculates + 1 from the last iteration so in this case the end result is: 33Foo 34Bar 35Baz public static void main(String[] args) {      int y = 0;          String[] arr= {"Foo", "Bar", "Baz"};         for(int i = 0; i < arr.length; i++) {              y++;         System.out.println(y +' '+ arr[i]);     }  }  while changing the above to double quotes:  public static void main(String[] args) {      int y = 0;          String[] arr= {"Foo", "Bar", "Baz"};         for(int i = 0; i < arr.length; i++) {              y++;         System.out.println(y +" "+ arr[i]);     }  }  will have the expected result: 1 Foo 2 Bar 3 Baz Anyone knows why? Just interested to know the reason of the impact using single vs double quote...


If the "Sentinel" Program existed since 1973 why it was never mentioned in the original trilogy of X-Men?

In X-Men DoFP we see that Trask Industries had developed a program to wipe out all mutants (the Sentinels). In the original timeline, though, where Mystique kills Trask and the American Government approves the "Sentinel" Program, why do we never get a single mention of it in X-Men 1, 2 or 3? Is it secret and it is uncovered only a few years after X3?  Note: This question is obviously different than  where the person who posted it is trying to figure out in which timeline every single event of the entire X-Men film series is happening, while my question is trying to explain if the absence of a mention to the "Sentinel" Program in the original X-Men trilogy is either a continuity error or is it explained somehow.


Unetbootin .Deb with all dependencies needed

Ok, so I did a fresh install of Ubuntu 17.04 Zesty. Me, being stupid like I sometimes am, didn't make a Windows 7 bootable USB. Windows was the only way I could get online(tether through pdanet). So I need someone to use an online Linux machine to apt-get the Deb package and dependencies for me so I can dual boot windows. It would be greatly appreciated being the other fastest way would be if I downloaded every single file one-by-one. Thanks!  EDIT: question isn't about creating the USB itself. It's about getting the program and all dependencies in one go.  EDIT 2: This isn't about making the usb its about helping me get the files on an offline machine with the only other device I have has android on it. I literally just need the deb files in an archive. I already know how to use the tools.


How to prove that field of rational functions is a *proper* subset of field of formal Laurent series?

Now, if $F$ is a field, I can prove easily that $F(x)\subseteq F((x))$ but I'm having problems to show this is a proper inclusion.   If for example $F=\Bbb R$ or $\Bbb C$, I can take a well-known function, say $\cos x$ and use its power series to show proper inclusing, because if   $$\left(F((x))\ni\right)\;\cos x=1-\frac{x^2}2+\frac{x^4}{24}-\cdots=\frac{f(x)}{g(x)}\in F(x)$$  then, since $f(x),g(x)\in F[x]$ (polynomials), we'd get that $\cos x$ has a finite number of zeros, which is absurd, and thus $\cos x\in F((x))\setminus F(x)$.  My problem now is: what to do if the field $F$ is not one of the usual, infinite ones? For example, if $F$ has positive characteristic?  Any input will be duly appreciated.


Is there a non-parametric Coefficient of Variation?

I was reading a  where the author mentions: "The coefficient of variation is primarily a descriptive statistic, but it is amenable to statistical inferences such as null hypothesis testing or confidence intervals. Standard procedures are often very dependent of the normality assumption and current work is exploring alternative procedures which are less dependent on this normality assumption."  The paper is from 2010. So my question is: has there been any recent "advancements" in terms of a coefficient of variation statistic that is not dependent upon the normality assumption? And, is this what one may call a non-parametric CV?


I've read a number of questions on stackoverflow regarding implicit and explicit constructors, but I'm still having trouble distinguishing between an implicit and explicit constructors.  I was wondering if someone could give me a good definition and some examples or maybe direct me to a book / resources that explains this concept well


Let $X$ be a metric space with metric $d$. Show that $d:X \times X \longrightarrow \mathbb{R}$ is continuous.

Can someone please verify my proof or offer suggestions for improvement?  I am aware that there is a similar question elsewhere, but I want help with my proof in particular.     Let $X$ be a metric space with metric $\operatorname{d}$. Show that $\operatorname{d}:X \times X \longrightarrow \mathbb{R}$ is continuous.   Let $U \subseteq \mathbb{R}$ be open. Assume $\operatorname{d}^{-1}(U) \neq \varnothing$.  Let $(x, y) \in \operatorname{d}^{-1}(U)$ and set $\epsilon_1 = \frac{1}{2}(b-\operatorname{d}(x, y))$  Clearly, if $(\alpha, \beta) \in B_d(x, \epsilon_1) \times B_d(y, \epsilon_1)$, then \begin{eqnarray} \operatorname{d}(\alpha, \beta) &\leq& \operatorname{d}(x, \alpha) + \operatorname{d}(x, y) + \operatorname{d}(y, \beta)\\ &<& \operatorname{d}(x, y) + 2\left(\frac{b-\operatorname{d}(x, y)}{2}\right) \\ \end{eqnarray}  That is,  $$\operatorname{d}(\alpha, \beta) < b$$  Similarly, set $\epsilon_2 = \frac{1}{2}(\operatorname{d}(x, y) - a)$.  Let $(\alpha, \beta) \in B_d(x, \epsilon_2) \times B_d(y, \epsilon_2)$. Assume, for the sake of contradiction, that $\operatorname{d}(\alpha, \beta) \leq a$.  Then,  \begin{eqnarray} \operatorname{d}(x, y) &\leq& \operatorname{d}(x, \alpha) + \operatorname{d}(\alpha, \beta) + \operatorname{d}(\beta, y) \\ \operatorname{d}(x, y) &<& \operatorname{d}(x, y)-a + \operatorname{d}(\alpha, \beta) \\ &<&  \operatorname{d}(x, y) \end{eqnarray}  Therefore, it must be the case that $$\operatorname{d}(\alpha, \beta) > a$$  Set $\epsilon = \operatorname{min}\{\epsilon_1, \epsilon_2\}$.  Then, if $(\alpha, \beta) \in B_d(x, \epsilon) \times B_d(y, \epsilon)$,  $$a < \operatorname{d}(\alpha, \beta) < b$$  Since $\operatorname{d}^{-1}(U)$ can be written as the union of open sets in the metric topology, it follows that $\operatorname{d}^{-1}(U)$ is open. Therefore, $d$ is continuous.


Sequence of continuous functions whose pointwise limit is discontinuous

Give an example of a sequence of continuous functions $f_n:\mathbb{R} \to \mathbb{R}$ such that the pointwise limit $f:\mathbb{R} \to \mathbb{R}$ exists but is discontinuous. My idea is $f_n(x)=\displaystyle\frac{x}{n}.$ Then the pointwise limit is $0$ but $f$ is discontinuous on $\mathbb{R}.$ Is that correct? I'm having a hard time understanding the definition of pointwise convergence. I have this definition: $\displaystyle\lim_{n\to \infty} f_n=f$ pointwise iff $\displaystyle\lim_{n\to \infty} f_n(x)=f(x)$ But then what is $f(x)$? Where does the $n$ go? In the example I gave, for instance, $\displaystyle\lim_{n\to \infty} f_n(x)=\displaystyle\lim_{n\to \infty} \frac{x}{n}=0.$ But does this equal $f(x)$? Is $f(x)$=0 a discontinuous limit?


How to explain an acronym inside a quote

I'm currently doing an essay and I haven't previously given context  "private contractors with top secret clearance had access to GCHQ databases." how d I explain what GCHQ is?  Is this correct? "private contractors with top secret clearance had access to GCHQ[Government Communications Headquarters] databases."  Or should I just put if after the quote?


How to prevent my screens from turning off, when the screen is locked?

I would like to have my screen fully powered at all times, but it goes to standby once I lock my PC.


Error when trying to install Lubuntu over Ubuntu

I am trying to install Lubuntu to replace Ubuntu, when executing the command on terminal it gives an error (below), please can someone shed a light? Many thanks fd@fd-lenovo:~$ sudo apt install lubuntu-desktop [sudo] password for fd:  Reading package lists... Done Building dependency tree        Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies.  gsettings-desktop-schemas : Breaks: mutter (< 3.31.4) but 3.28.4-0ubuntu18.04.2 is to be installed  lubuntu-desktop : Depends: lxqt-core but it is not going to be installed                    Recommends: hplip but it is not going to be installed E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.


I need help understading why this code shows same String with alert()

I'm learning Javascript and I've run into this exercise. I need some clue or explanation for understanding and solve the problem.  I assume it's something simple, but I can't see it, and I can only modify the indicated area.  var test_method = function () {     return {         config: {             "test_string": ""         },         init: function () {             alert(this.config.test_string);         }     } }();   // Modifiable area test_method.config.test_string = "Hello";  test_method2 = test_method;  test_method2.config.test_string = "Good Bye"; // END Modifiable area   test_method.init(); test_method2.init();   The exercise says that the alert() must show in first place "Hello" and then "Good Bye", but now only says "Good Bye" two times.


YA fantasy about a girl being turned into a book by a magician

This e-book was released in 2017. The 2 main characters are a boy and a girl in different worlds. There was another girl turned into a book by a magician. The boy found the book and wants to restore her back to her body. He can talk to the book. The boy can also move between different worlds.   The boy started out as a teacher in a school. The school was destroyed and everyone had to leave. He later joins some rebels who wanted to kill the leader of some other race who had oppressed their world. He was skilled in traveling between worlds. He also double-crosses the rebels by aligning with the leader of the oppressors.  The girl fell in love with an artist in her own world. She broke the rules because she could do something with colors. The leader of the oppressors starts to train her to be powerful.


Integrate :- $\displaystyle\int\dfrac{2x^2}{2x\cos(2x)+(x^2-1)\sin(2x)}$   I tried dividing by $\cos^2(x)$ and then substituting $\tan(x)=t$.


I tried to upgrade from 11.04 to 11.10 so that I can get to 12.10-14.04

The problem is that through terminal I get a "didn't download". There may be a problem with network connection, I am using WIFI?


\mathbb{Z} yields undefined control sequence error

I am using WinEdt 6 for compiling my TeX documents. I am getting an error with contains the line $\mathbb{Z}$ showing that it is undefined control sequence. How should I rectify it? Should I include any math packages or something. I am a beginner in using TeX.


I just read  where he mentions that 50 rep should be enough for a user to have learned not to post "+1 AWESOME ANSWER!!1" comments.  Well, that got me thinking, I post a fair few "+1" comments, and now I feel shame.  Sometimes I do it to:   Highlight the good part of an answer Add something I hope has value Let a user know that I really think they went above and beyond In a young SE site, leave a marker for other new users to notice especially good answers   What makes a good +1 comment, and when should I just keep it to myself?


Why we use serialVersionUID during serialization

In my interview i got one question how to achive Serialization and I gave answer as   public class SerializationSample {     public static void main(String args[]) {         ...........         FileOutputStream fos = new FileOutputStream(outFile);         ObjectOutputStream oos = new ObjectOutputStream(fos);         oos.writeObject(serializableObject);         ............ } class SerializationBox implements Serializable {     ............     ............ }   but the interviewer told, this will serialize whole object and he asked 2 questions    How you will write a code if i want to serialize single object? Why we use long_integer id during serialization?   Please any one can help me to finding answer for this question


GUIDs (or ) are usually stored as 128-bit values, and are commonly displayed as 32 hexadecimal digits with groups separated by hyphens, such as:   21EC2020-3AEA-4069-A2DD-08002B30309D   Online resources are available for , but I'd like to create on during compile time. Ideally I'm interested in a macro \GUID that would produce a GUID (that I can store in a macro), perhaps using the computer time to initialise a pseudo-random number generator. If possible, perhaps an optional argument would allow one to supply a seed that should return a fixed GUID.  I'm specifically interested in  which have the following format:  Hex digits  Description 8           Data1 4           Data2 4           Data3 4           Initial two bytes from Data4 12          Remaining six bytes from Data4   "Version 4 GUIDs simply use a pseudo-random number for filling in all but six of the bits. They have a 4 in the 4-bit version position, and the first two bits of data4 are 1 and 0 (so the first hex digit of data4 is 8, 9, A, or B), for example 38A52BE4-9352-453E-AF97-5C3B448652F0. More specifically, the data3 bit pattern would be [...] 0100xxxxxxxxxxxx [...]."


Historical Stock Prices of delisted company

With services like Google Finance or Yahoo Finance it is very convenient to find the historical stock price metric of a listed company, but if the company is not listed, I can't find the data.  For example, I want to see the price metrics for Lawson Software, which had been listed  on NASDAQ (LWSN). How could I find its historical price metrics?


How can i start ubuntu side by side with windows 7 32bit?

Need help how can I work on ubuntu but also have windows?


I'm a native English speaker and I consider myself to have a very competent understanding of English grammar.  Recently, I have started believing that there is no future tense in English grammar.  Here are some examples of sentences that I previously believed were future tense, but now believe are either present tense or invalid (broken) English grammar:     I will do my homework tomorrow.    I say that this is present tense. The full (uncontracted) sentence is      I (have the/a) will to do my homework tomorrow.    Strictly, this sentence refers to the writer's will in the present. The usage seems to have been contracted in recent centuries, but "will" remains a noun and this seems to be the only grammatically-valid interpretation of this sentence.     I am going to the bathroom.    I say that this is present tense.  The only valid interpretation of this sentence is that the speaker is currently going to the bathroom (in the present, right now). Whether "going to the bathroom" means traveling to a bathroom or peeing in their pants is open to interpretation, but this does not affect the tense. The tense is determined by "am", so the tense is present.     I am going to school tomorrow.    I say this is invalid English grammar.  This is as invalid as I am going to school yesterday. The tense is present because of "am", and the sentence can not be validly interpreted as it stands.  In examples such as      We are going to Italy in Spring,    this is invalid for the same reason as above: "are" determines that the tense is present, and then a non-present time period is appended. This is as invalid as      We are going to Italy two years ago.   These are just a couple of examples but I have looked at many examples of future tense usage and I do not believe there is a valid future tense in English grammar.  Question: Is it true that English has no future tense?


Python - with open() except (FileNotFoundError)?

It seems strange to me that  with open(file, 'r')   can report   FileNotFoundError: [Errno 2]   but I can't catch that in some way and continue on.  Am I missing something here or is it really expected that you use isfile() or similar before a with open() ?


so toray my computer was slowing down, so I checked the task manager to see what was going on. and svchost.exe was using about 1GB of ram. anyone have an idea to stop this?  os: Win 7 (non-genuine since I have used the same HDD in many PC's)


Questions changed on getting answer to current question

I have seen that users ask questions related to code and, when they get solution to their current problem, they just make those changes to code in current question itself and change the question asking their next problem. This makes the already given answers irrelevant to the current question.   So is there any way to mark such questions?   I just commented that its better to add a new question than editing same question.


Limit of $\lim _{\left(x,y\right)\to \left(0,0\right)}\left(\left(xy\right)\ln \left(x^2+y^2\right)\right)$

I want to calculate limit of  $\lim _{\left(x,y\right)\to \left(0,0\right)}\left(\left(xy\right)\ln \left(x^2+y^2\right)\right)$ using Squeeze theorem or using definition of limit. please help


When writing software documentation I very often have to describe things like a value manager, a value cache or a device map. These are usually components of the software system. In practice the manager does of course not manage a single value but many and the map does not map only a single device etc. My question is: is it more common to speak of a values manager instead of a value manager and of a devices map instead of a device map etc.?


I am new on Linux based operation systems.It will be my first time so I need your help. I just bought HP Pavilion 14-CE3005NT and it has great hardwares but the processor. The hardware list of this computer is: Graphics Card:Nvidia GeForce MX250 RAM:16GB(DDR4) 512 GB SSD Processor:Intel i7 1065G7 (1.3 GHz) And when I read Ubuntu 20.04 system requirements,it says 2 GHz dual core processor required.And my processor speed is 1.3 GHz. Would it cause a problem to run latest version of Ubuntu perfectly? Note:I will be computer science student from this year. I will just use my laptop for coding and I wanna start using Ubuntu to improve myself quickly.So,please let me know if I can run compilers and other software for game development etc. too. Thank you.


How many times can one enter Thailand with a tourist visa in these circumstances?

I am a bit confused because I read pretty different informations online. Let's assume this scenario:   UK passport holder. Older than 18 years old but younger than 50. Otherwise no criminal records or exceptional thing. Never visited Thailand before. Flies to Thailand (no prior visa). Gets stamped for 30 days. Before 30 days, renews other 30 days. Before 30 days, renews again (approaching 90 days now) Before 90 days, flies out (no overstay) Flies back to Thailand within one week, and repeats the same operation.   By searching for regulations online, I do not see any regulation on Thai tourist visa policy that explicitly avoids this. However, I see a lot of people online claiming in practice this cannot be done.  Are there any numbers about how often this can be accomplished? Is this in any regulation or is just randomly done by the on-duty immigration officer?


How to reset cql_filter of WMS on OpenLayers 3?

I can dynamically change the CQL filter, but I want to reset it to default (get WMS without any filter).  Class I am using  "ol.source.TileWMS" as source from GeoServer   Here is my code to which I used to update the CQL filter:  overlay_layer_definition_array[selected_layer].getSource().updateParams({  'LAYERS': Lay_Param[selected_layer][1] + ':'         + Lay_Param[selected_layer][2]   ,'cql_filter': ''+strUser+strUser1+strUser2});   The above code works fine, but now I don't want to pass any filter, tried all of below     does not work   refresh() does not work   'cql_filter': nil does not work   'cql_filter': 'nil'  does not work


How can I tell which version a classic World of Darkness book is for?

I'm a novice in the World of Darkness games. Most of my books are purchased piece-meal through game stores. This  has been incredibly helpful in laying out the various games and editions that exist.  I have around 30 books of various classic World of Darkness product lines - Vampire, Hunter, Werewolf, etc.  However, most of the books don't explicitly say what version of the game they are for (1st, 2nd, revised, x20, V5, etc.). This leaves me confused about which materials are appropriate for which games - and where to put them on my shelf!  How can I tell whether my books are intended for 1st, 2nd, revised, x20, or some other edition? Are there tradedress somewhere I should be observing? Or unique mechanical elements that differ?


Why is the ratio of circumference to diameter $\pi$, and not any other number?

How do we specifically get to 3.14 from axioms through logic to that particular transcendental number being the case?  I'm guessing it's the sum of an infinite series. But how do we go from "there's a circle" to "this particular infinite series describes the ratio of the diameter to the circumference", other than getting out a tape measure, and noticing that the series seems to produce the same number (sans any proof). I'm looking for the proof of why the circumference/diameter = 3.14... specifically.


Can I change the physical monitor dimensions in "Rearrange your displays" on windows

This is my setup at work:    The two monitors have a resolution of 1920 X 1080. The Dell XPS 13 has a resolution of 3840 X 2160  Trying to set up multiple screens in Windows makes the setup weird, as if the laptop monitor is way larger than the desktop monitors. This is because it has a higher resolution at a higher PPI. This makes moving the mouse between the monitors very awkward.   Is there a way to make Windows realize that despite the higher resolution of the laptop screen, it is in fact physically smaller in dimension?


what is the meaning of "-m state --state RELATED,ESTABLISHED"?

I found this rules on iptables  -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT   what is the meaning of -m state --state RELATED,ESTABLISHED ?  and why without this rule I can not ping www.google.cn ?  thank you very much ^_^


Win7: Invert Colors Of One Specific Window

I often use ctrl+alt+I and windows magnifier to invert the colors of my screen, to make bright windows easier to read.  The problem is that, eg, some windows are naturally dark and some are naturally light, and so I find myself often toggling the inversion as I switch between windows.  I would like to be able to apply preferences on a per-window basis: eg, my email client is white-based and I would like to keep it always inverted.    Is there a way to accomplish this?


What is variable length instruction, What is its importnace in 32 and 64 bit OS

While reading   about 32 bit vs 64  bit OS i came to know that there is instruction length varies from 32 bit to 64 bit.  What actually it means and what is its importance?


How do color spaces like sRGB and Adobe RGB overlap?

Is sRGB included in Adobe RGB, and Adobe RGB included in ProPhoto RGB? Meaning that a photo in a "lower space" will look like exactly the same in a "higher space", e.g. a sRGB photo will look like exactly the same in a Adobe RGB space.  I noticed the size of a sRGB photo is bigger than the same one in Adobe RGB, which I don't understand since the color space is bigger.


I am designing a guitar pedal using OpAmps, and i need to feed them with +6V and -6V (beucase the musical signal is senoidal centered in 0V). I need to use a 12V DC PSU for the pedal, and i need to convert to positive and negative voltage. If possible it would be better if it was +12V and -12V but if its not possible i can work with +-6V. I also need this to be reasonably simple and cheap. Thanks!


I could not find any way to solve this question. Let $\{ a_n\}$ be a sequence of real numbers with $\lim_{n \to \infty} n\, a_n = \alpha >0$, and let $f(x)$ be real-valued continuous function on $[0,\infty)$ with $\lim_{x \to \infty} f(x)=k$. Compute $$ \lim_{n\to \infty} \frac{1}{n} \int_{0}^{\infty} f(x) e^{- a_n  x} dx.$$


I was trying to solve questions from "Mathematical Analysis" by "Apostol" and came across this question which states  ""If $a, b, c$ and $d$ are rational and if $x$ is irrational, prove that $\dfrac{\left( ax + b \right)}{\left( cx + d \right)}$ is usually irrational.""  Now, the problem with this is that how can we prove something is usually True? All we can do is to show some cases where this is not true. Like in this example, we can give the solution as:-  The only time it will be rational is when the numerator is some integer times the denominator or vice - versa. The rest of the times, when this is not true, it will be irrational.  Is this the correct way of proof or there is some other war to prove something usually true?  Note: My question is not about finding the possibilities that the given expression is rational. The question is about how to prove something usually True? Because, as far as I have learnt about logic, we may prove something to be True (completely) or False (by just giving one counter example). So, here, I am asking that if such a statement comes, what does it mean to prove it? In fact, I have solved the question and its solution is written in the explaination. All I want to know is that if my solution is correct or is there a proper way to prove something usually True?


Strange php behavior involving type casting

Easier to see via examples.  All of them with the following php version:  $ php --version PHP 7.4.4 (cli) (built: Mar 18 2020 04:33:54) ( NTS ) ...    Exhibit 1:  $ echo '<?php for ($i = 0; $i <= 10; ++$i ) {  print( (int)(100 * ($i + 0.7)) . "\n"); } ?>' | php 70 170 270 370 470 570 670 770 869  <<< uh? 969  <<< uh? 1070    Exhibit 2 replacing the type casting by float:  $ echo '<?php for ($i = 0; $i <= 10; ++$i ) {  print( (float)(100 * ($i + 0.7)) . "\n"); } ?>' | php 70 170 270 370 470 570 670 770 870 970 1070   The question is:   Why does the Exhibit 1 results happen?


As light is electromagnetic radiation. Then why I don't see any magnet bending light wave? Or why light doesn't diffract whenever it passes by a live wire?


I'm having this problem in Blender that it is only loading the text, I am very new to this and don't know why it is cutting out what is even in the camera view and making it black. If you could help me, I would really appreciate it.   It's only rendering 'Kenny Miller" and not the green/black back:  [


If $p$ is a prime greater than 2 and divides $x^p$ + $y^p$ prove that $p^2$ divides $x^p$ + $y^p$ (Not sure if its possible)

So this is a question in my discrete math's Textbook and according to our teacher our schools math's department has not been able to solve this question in 4 years of trying. So I bring this challenge to you. Either try and prove it or prove that it is not possible and that there is a mistake in the question.  This was under the Fermat's little theorem section of discrete mathematics.  $p$ is a prime number bigger than two. $p\mid(x^p + y^p)$ prove that $p^2\mid x^p + y^p$


.erase not removing all specified values

I'm trying to remove all instances of certain values from a vector, however when there are only one or two instances of the same value, one instance of the value remains: //Removing any values in arr that match the values in copies vector<int> arr = {100,100,50,40,40,20,10}; vector<int> copies = {100,40};  for(int i = 0; i < copies.size(); i++)     {         vector<int>::iterator j = find(arr.begin(), arr.end(), copies[i]);         arr.erase(j);     }  With this code, arr returns as {100,50,40,20,10} but if there are three or more instances of these values, .erase will remove them all If anybody could explain why having one or two of the same value will save one from being erased I would greatly appreciate it.


How do I calculate the power rating for zero-ohm resistors?

Based on my , since there supposed to be zero voltage (V=IR) drop across a 0 Ω resistor, how do we select the  of such a component?  For example, let's say I were to connect a zero-ohm resistor in between 5 V power source and a load (circuit variant) which take current ranges from 20-200 mA. What is the power rating of the 0 Ω resistor I should select?


Which algorithm for forecasting a binary time series?

I would like to write the code to forecast the status. The status 0 means non-active, 1 means active. I would like to predict the future month (e.g 2016/6/1), the status should be "0" or "1".    What algorithm could be used in such a situation?  date       status 2016/1/10   0 2016/1/19   0 2016/2/2    1 2016/2/10   1 2016/3/1    0 2016/4/2    1 2016/4/3    0 2016/5/4    0 2016/5/5    1


Working on Java 7, i have the following String date = "12/04/2012".  I converted the String to a Date format:  Date date_converted = DateUtils.parse(DateUtils.STANDARD, date);   Now i want to add a day to my Date, someone can help me?


I'm pretty new to JavaScript/AngularJS, I would like to delete an object in an object.  Let's take this for example:  var heroes = {   0: {        name: 'Batman',       gender: 'M'   },   1: {       name: 'Superman',       gender: 'M'   },   3: {       name: 'Catwoman',       gender: 'F'   } };     I would like to delete the object when gender == 'F'.  for(var hero of heroes) {     if(hero.gender == 'F') {         //Delete her     } }   delete hero does not work, I have:     SyntaxError: applying the 'delete' operator to an unqualified name is   deprecated


What's the difference between convolution and crosscorrelation? So why do you use '-' for convolution and '+' for crosscorrelation? Why do we need the "time reversal on one of the inputs" when doing convolution?


Is it safe to roast marshmallows over a sterno flame?

It's become common practice around my apartment to use a sterno to roast marshmallows because it's easy, cheap and (primarily) because we can't have a campfire in my living room.  Is this dangerous?


Exact sequences of $1 \to A \to SU(N) \to B \to 1$, special unitary group

Inspired by the , I am particularly looking into the exact sequences of SU(N), but I will like to loosen the conditions of the previous ,     Q1. $$1 \to A \to SU(N) \to B \to 1$$   where any of $A$,$B$ can contain finite group or discrete groups.    I am particularly interested in SU(5),     Q2. $$1 \to A \to SU(5) \to B \to 1$$    I wonder whether there is any example such that both $A$ and $B$ contains the same number of generators of continuous part of Lie groups (there can be an additional discrete finite group parts such as additional $\mathbb{Z_N}$)? (for example $SU(5)$ has 24 generators. Is there any example such that $A$ and $B$ have 12 generators for continuous part of Lie groups for each $A$, $B$.) How about  $$A=U(1) \times SU(2) \times SU(3)\;\;\; \text{or} \;\;\;A \supset U(1) \times SU(2) \times SU(3)?$$  Or whether there is any example such that $B$  $$B=U(1) \times SU(2) \times SU(3)\;\;\; \text{or} \;\;\;B \supseteq U(1) \times SU(2) \times SU(3)?$$ (there can be an additional discrete finite group parts for $B$ such as additional $\mathbb{Z_N}$.)


How to find cores and logical processors in SQL Server

I can see 4 processors when i right click on SQL server instance -> properties->General->Processors,  does it mean is the server had 2 core processor or 4 core processor? what is CORE? where do i check how many cores sql server has?  Very much appreciate your replies


Extending root partition in ubuntu 14.04 LTS

How do I extend the partition size of /dev/sda5 by merging it with unallocated space of 20.0GB    EDIT:   When I try to create a new partition(using the unallocated space) I get the following error  It is not possible to create more than 4 primary partitions


So my mom just bought a new Iphone 7 and she wants me to transfer ONLY her contacts to her new phone but cant i just login in with the apple ID on the New phone and everything would restore on it? If not please show a easy way to do this


a=Hello-World b=$(a|cut -d- -f1) echo "$b"   The above commands are not working for me. Any input?


Showing vertices outside editing session in ArcMap?

Does anybody know, if it is possible to see features' vertices (or all) when you are not in editing mode?


Zoom into country polygon with Leaflet with mouse click

I have a GeoJSON file and I'm trying to create a click event to zoom into the specific country. I would also like to zoom out. So far the click events is not working, what am I doing wrong?     // Creating map object     var myMap = L.map("map", {       center: [10.0522, -10.2437],       zoom: 3     });     // Adding tile layer     L.tileLayer("https://api.mapbox.com/styles/v1/mapbox/light-v10/tiles/256/{z}/{x}/{y}?access_token={accessToken}", {       attribution: "© Mapbox © OpenStreetMap Improve this map",       tileSize: 512,       maxZoom: 18,       zoomOffset: -1,       id: "mapbox/light-v10",       accessToken: API_KEY     }).addTo(myMap);     // Load in geojson data     var geoData = "static/data/map.geojson";     var geojson;     // Grab data with d3     d3.json(geoData, function(data) {       // Create a new choropleth layer       geojson = L.choropleth(data, {         // Define what  property in the features to use         valueProperty: "coordinates",         // Set color scale     scale: ["#ffffb2", "#b10026"],     // Number of breaks in step range     steps: 10,     // q for quartile, e for equidistant, k for k-means     mode: "q",     style: {       // Border color       color: "#fff",       weight: 1,       fillOpacity: 0.8     },     // Binding a pop-up to each layer     onEachFeature: function(feature, layer) {       layer.bindPopup("Name: " + feature.properties.name + "
Nr Loans:
" + feature.properties.name);     }   }).addTo(myMap);   markers.on("click", function (event) {     // Assuming the clicked feature is a shape, not a point marker.     map.fitBounds(event.layer.getBounds());   });   markers.addTo(map);


Can Node Frames be saved for recall later?

Can Node Frames be saved for recall later maybe in another project? Are they (frames) managed as object data in and of their own right?


What is the promotion rate of professors in United States?

I'm writing an essay, and want to know the promotion rate and average duration from assistant professor to associate professor and associate professor to professor in recent years. Sadly I don't know the data for the US. Could anyone tell me?


For A/B testing purposes i'd like to change the class name of an  element. I can add Javascript to the A/B testing tool to achieve this. As i'm quite new to javascript, i could use some help.  The current  element:
   Must be changed to:
   How can i perform this by using Javascript?


My book specifies a function: $$\Bbb{R^n}\times\Bbb{R^m}\to\Bbb{R^m}$$ What is the difference between $\Bbb{R^n}\times\Bbb{R^m}$ and $\Bbb{R^{m+n}}$? And if there is none, what are the relative advantages of writing $\Bbb{R^n}\times\Bbb{R^m}$ over $\Bbb{R^{m+n}}$?  Thanks.


Percentage of overlapping regions of two normal distributions

I was wondering, given two normal distributions with $\sigma_1,\ \mu_1$ and $\sigma_2, \ \mu_2$   how can I calculate the percentage of overlapping regions of two distributions? I suppose this problem has a specific name, are you aware of any particular name describing this problem?  Are you aware of any implementation of this (e.g., Java code)?


I want to search for a line in a file and then substitute that line for another. I've found this question:  In the main question the user asks for a replace function, that works like this:  f = open(file) for line in f:     if line.contains('foo'):         newline = line.replace('foo', 'bar')         # how to write this newline back to the file   , which is exactly what i need but i can't seem to get it to work. Can someone maybe explicitly use the replace function given in the answer for the problem above and write the code down? (I don't know what to put for "file_path" in the replace function. Is there some way to just tell python to use the current directory or something like that?)  Sorry if it is a trivial question but I've been strugling with it for quite some time now and i can't get it to work. Thanks in advance!


Can you tag multiple people in a comment?

When replying to comments you can do @username to make sure they get a notification of your response. But what should you do if you wanted to get the attention of to people? Would @username @username2 do that, or should you make two different comments?


Disable 'remember password' prompt from javascript or code behind

I need to disable "Remember Password" prompt coming in browser, either through code behind or from javascript. Thanks in advance


Verifying validity of proof that E' is closed

According to Rudin's principles of mathematical analysis 2.24 (a):  If a set $A$ and $B$ are open sets then $A /cup B$ is open. Therefore we have 4 possible scenarios letting $A=E$ and $B=E'$ where $E'$ is the set of limit points of $E$:  1.) $E$ and $E'$ are closed. Therefore $\overline{E}=E$ by theorem 2.27 (a)  2.) $E$ is closed and $E'$ is open.   3.) $E$ is open and $E'$ is closed (okay since $E'$ is closed.  4.) $E$ and $E'$ are open. Which is a contradiction of theorem 2.24 (a).  In the case of 2.) by definition, if $E$ is closed, then every limit point of $E$ is in $E$. That is, $E' \subset E$. Since every point of $E'$ is in $E$ (a closed set) then $E'$ must be closed. (Unsure about whether this is sufficient)   This is my attempt so far to prove that $E'$ is closed using axioms. If there is something I am missing or anything that needs to be modified I would appreciate it.  EDIT: using theorem 2.27 (b) if $E$ is closed then $E = \overline{E}$. Thus for 2.) if we take the set of limit points of the equality, we obtain $E' = (\overline{E})'$ then I must show that $E'= (E \cup E')' = \overline{E'}$.


I have RHEL (virtual box) server that I need to install puppet modules from a puppet master. I was told to log in as root then run puppet agent command. So I ran following command.  sudo su puppet agent -t   Execution went fine without an error. Let's say file "A" was pushed down from the master to the target server but I noticed that file size of "A" did not match between the master and the target server. I thought that was odd....I removed the file "A" from the target server then logged out and logged back in as root BUT with hypen "-" this time then ran puppet agent command.  sudo su - puppet agent -t   Execution went fine without an error BUT this time the file size of "A" matched. I am curious to know why.


Term for Gift that Turns out to be a Burden

What is the English term for when someone thinks they are doing something nice for you but it ends up making things worse. EX: Someone buys you an elephant -- nice gesture and cool! But now you have to take care of it, and it becomes a burden on you.


Can't Convert to Curve|Mesh using ALT+C in linux

In Blender 2.79 and 2.80 on os Linux the command ALT+C  (Convert to Curve|Mesh) does not work: pressing the keys does not cause any results. Note that in the preferences the shortcut is correctly set.  In Windows everything is OK.  Any ideas?


I want to make a adapter from a vehicles 24v to a 5v usb phone charger. Can I simply connect the wires from a cigaret lighter jack to a usb and add a resister in between (using a voltage divider)? If so does it matter how strong the resistors are (assuming the ratio is correct?


Is there a workaround to make CSS classes with names that start with numbers valid?

Is it referenced anywhere that CSS classes with names start with numbers doesn't work? for example I found that a class with background like:  .000000-8 {background:url(../../images/common/000000-0.8.png);} .8FFFFFF {background:url(../../images/common/FFFFFF-0.8.png);}   doesn't work in most browsers I have and the  shows that but my question is there a workaround to make CSS classes with names that start with numbers valid? .


Book where a group of young magicians/teenagers travel the world to find magic enhancing gems/items to defeat the evil lord

I read this fantasy trilogy (maybe even 4-5 books) about 15 years ago. I'm not sure it is a Young Adult series, but it was published at least 20 years ago. My memory of the books is quite fuzzy, but I will describe the parts I remember as well as possible. It starts with a male protagonist (probably about 16ish years old) who lives in a castle. His parents/family might have been the rulers of the area. As some of the residents (probably his parents?) were assassinated/attacked, he has to flee with (a) companion(s). The reason for the attack was a (long-lasting) war with the neighbouring country, under the rule of a dark lord. The enemy might have been beast-like, but I'm not sure about that. We learn that the dark lord has magic powers and that the protagonists can defeat him with their magic. However, it is necessary to find some rare magic enhancing gems/items that are lost through the ages. If I remember correctly, they end up with a group of 7 (I hope I got this number correct) protagonists. Along their journey, they find these gems, and every one of them has a unique ability. I remember one of the gems would enhance/give the power to fire flames (it was red), and it was found in/under a big rock. They found it because one of the protagonists could trace the imprints of the flames left in the surrounding rocks/buildings/ground. Two of the late acquired items were a silver/gold kelk and a gold/silver sword (don't remember which was what material, the sword was probably silver). They could identify the goblet/chalice (there were fake goblets in circulation) because it was one of the hardest materials in the world and could only be scratched by the sword, which they recently acquired. Regarding the series, I also remember a few details. The setting was medieval, and the protagonists country's warriors wore armour of impenetrable gems, that glittered in the light. This was an important aspect highlighted in the first book, as the armour of the knight regarded as priceless. The cover of The Way of Kings by Brandon Sanderson reminds me of the cover of the first book. One of the 7(?) protagonists is a girl named Atara (or Altara, something similar). Lastly, one of the books is called something like Sword of Light and the series is called something like The Trilogy (if it's not a trilogy then Books or something similar) of Eve (or Ava/Avaen, idk sorry). I know these are a lot of random facts (maybe not really facts) and I'm quite frustrated that I am not able to find the series knowing some of the detailed points. Hopefully, you can help me out, I have been looking for ages :) The only series that I could find that somewhat fits this story is Deltora Quest, but that is not it. (The books I'm looking for are not so childish.)


How to add comments in align environment

I find it is necessary to add some explanation in a series of equations. Ideally, I would like to get something like the following picture (Resnick 1999). As you can see, the equations are still aligned but with extra comments added. Could anyone tell me how to do this in LaTeX, please? Can I achieve this using align environment, please? Thank you!      Here is an example. Note that I want my comments to align with the main text.  \documentclass{article}  \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsthm} \usepackage{amsmath} \usepackage{manfnt}  \begin{document}  \noindent I want the comments to align with the main text.  \begin{align*} \mathbb E X &= \int x F(dx) \\ comments \\ &= \mu. \end{align*}  \end{document}


What is the Complexity of Find() Function

I have two versions of find function, both of which search an integer value in an array and return its position if exists. Function find1() will search up to N elements in worst case on the other hand find2() function will search up to N/2 elements in worst case. Does it mean find2() functions complexity is reduced into O(N/2)?  I assume the array arr contains non-duplicating values.  Function: find1()  int find1(int value){     for (int i = 0; i < N; i++){         if (arr[i] == value){             return i;         }     }     return -1; }   Function: find2()  int find2(int value){     for (int i = 0, j = N - 1; i <= j; i++, j--){         if (arr[i] == value){             return i;         }         if (arr[j] == value){             return j;         }     }     return -1; }


solving third-order nonlinear ordinary differential equation

I would like to solve:  $(\frac{d^{2}y}{dx^{2}})^2+\frac{d^{3}y}{dx^{3}} \frac{dy}{dx}=0$   Thanks in advance.


I want to learn more about udev rules, so I implemented a simple one, but I doesn't work:  /etc/udev/rules.d:  KERNEL=="sdb1" ACTION=="add"  RUN+="~/test/exe.sh"   ~/test/exe.sh:  #!/bin/bash echo "USB plugged in" > ~/test/showup.txt   the .sh file is executable, and I checked the flash drive's name via lsblk. It is called sdb and has a sdb1 partition.  I already looked up different tutorials, but can't find my mistake. I use Arch Linux in case that matters.


W8.1 won't boot "Your PC did not start correctly", Startup Repair error : "root cause found: registry is corrupt"

My PC (Windows 8.1, dual booting with Windows 10 Dev Preview) won't boot, every time I try it just goes to Automatic Repair which always fails. Things I tried:   Safe mode doesn't work (goes to Automatic Repair). sfc /scannow doesn't work (message: There is a system repair pending ...) sfc /scannow /offbootdir=d: /offwindir=c:\windows didn't work either. (message: Windows Resource Protection could not perform the requested operation.) I did chkdsk /r c: twice didn't find any errors. Tried Startup repair with installation USB a couple of times, most recent one said "root cause found: registry is corrupt" When I first tried System Restore I was able to see restore points (the latest restore point was a windows update of the 13th but it didn't let me restore saying that I need to enable the system protection, my PC stopped working on the 14th) but I can't see any restore points. Refresh doesn't work. (message: There was a problem refreshing your PC. No changes were made) bootrec /fixmbr, bootrec /fixboot, bootrec /rebuildbcd none of them worked.   I do have registry back ups, but I'm not sure how to do a restore if I can't go to safe mode. Is there anything else I should try before giving up and reinstalling?


Prove $\frac{a}{b}+ \frac{b}{c}+ \frac{c}{a}\geq \frac{1}{a}+ \frac{1}{b}+ \frac{1}{c}$

Give $a, b. c$ be the lengths of a triangle and $a+ b+ c= 3$. Prove that: $$\frac{a}{b}+ \frac{b}{c}+ \frac{c}{a}\geq  \frac{1}{a}+ \frac{1}{b}+ \frac{1}{c}$$ My try  We have England MO inequality: $$\left ( \frac{a}{b}+ \frac{b}{c}+ \frac{c}{a} \right )^{2}\geq  \left ( a+ b+ c \right )\left ( \frac{1}{a}+ \frac{1}{b}+ \frac{1}{c} \right )$$  and $$\frac{a}{b}+ \frac{b}{c}+ \frac{c}{a} \geq  3=  a+ b+ c$$  But it cannot be used to prove the above inequality and how to use triangle inequality in this inequality. I need the help. Thanks!


Printing escape sequence character in python

I tried to print the escape sequence characters or the ASCII representation of numbers in Python in a for loop.  Like:  for i in range(100, 150):     b = "\%d" %i     print(b)   I expected the output like,  A B C   Or something.  But I got like,  \100 \101   How to print ASCII representation of the numbers?


How to create automatic dual battery changeover/switching circuit for uninterruptible power?

I've search for a solution to my problem both on this site and on Google but I did not find a complete and adequate response.  I need a circuit that switches two 12v sources (one that comes from a lead-acid battery powered by a solar panel and the other source comes from the output of a 220-12v switching power supply) without the final power output being interrupted during switching (this is very important!).  Notes:  - The final power output will be used to power 12v devices (30 Ampere maximum).  - The sources voltage range is 11-14.7v  How can I switch between two 12V sources?


Why doesn't my Feed-forward NN work when I try to train it with multiple inputs?

Basically I am trying to create a Neural Network in c# from scratch, without using any libraries. The issue that I am facing with right now is whenever I try to train my network with different inputs it simply does not work.  For example, I tried solving a basic problem like the XOR logic gate with my NN. Whenever i use the complete training set (all the possible combinations of 1s and 0s) my NN cannot set the weights in such a way that it could produce the desired output. If I train my NN with all the possible variation of inputs after a while instead of setting the weights properly it sets them in a way that the output in each case is around 0.5. On the other hand, if I train it with only one input combination (e.g.: 1,1) it gives the desired output (0).  Any idea why it could be? I use backpropagation to change the weights. My activation function is sigmoid and the cost function is the squared error function. NN has one hidden layer. I also observed that the actual value changes depending on the type of problem. For example when I tried the NN on OR gate it was ~0.75. (Not surprising given that it will be "on" 3 times out of 4)


Changing a user's password within a script doesn't work

For reasons I want to change a user's password to a random one every X minutes using a script. It's a debian machine, the following script is started via @reboot in root's crontab and the script is running. Every X minutes the new password is written to the file specified in the script, however, the password is never changed.  #!/bin/bash # change user's password to a random one on boot and every five minutes  while : ; do     npasswd=$(pwgen 8 1)     echo "$npasswd" > /root/current-user-passwd.txt     usermod --password $(openssl passwd -1 "$npasswd") user #   echo "$npasswd" | passwd user #   usermod -p $(perl -e "print crypt("$npasswd","Q4")") user     sleep 300 done   I have tried each of the three methods (the other two being commented out now), none work. However, when I copy the entire script and just paste it in a terminal to run it, it works perfectly fine. It just doesn't work in a script if it's started by cron.  Does anyone know what is going on here? I've also tried echo -n by the way, same results. I've also tried to set $npasswd in the script to something fixed, just to test it, same results.  Just to clearify: I'm really looking for an answer that explains why this is working manually, but not in a script, not for an alternative way to change the password. Those methods do work, just not if the script is started by cron.  Output of the script with set -o errexit -o nounset -o xtrace on top:  + : ++ pwgen 8 1 + npasswd=eiZeed5u + echo eiZeed5u ++ openssl passwd -1 eiZeed5u + usermod --password '$1$EYRCYJXm$5XkrVNxdrYRzxBmcRwuXm0' user + sleep 300   Output of the above when started via cron's @reboot:  + : + pwgen 8 1 + npasswd=aizof5Ka + echo aizof5Ka + openssl passwd -1 aizof5Ka + usermod --password $1$KFrgibYH$e1dMUeF2AzTtSPExBjbXo1 user /root/change-user-passwd.sh: 8: /root/change-user-passwd.sh: usermod: not found   Which makes the issue clear to me now, thanks @!