Physics.CheckSphere() appears not to work in Unity

My scene is simple, I have a single GameObject with the following script attached: usings ...  public class GalaxyManager: MonoBehaviour {     public int numberOfStars = 300;     public int maximumRadius = 100;      public float minDistBetweenStars = 2f;      void Start()     {         for (int i = 0; i < numberOfStars; i++)         {             float distance = UnityEngine.Random.Range(0, maximumRadius);             float angle = UnityEngine.Random.Range(0, 2 * Mathf.PI);              Vector3 cartPosition = new Vector3(distance * Mathf.Cos(angle), 0, distance * Mathf.Sin(angle));              if (!Physics.CheckSphere(cartPosition, minDistBetweenStars))             {                 GameObject star = GameObject.CreatePrimitive(PrimitiveType.Sphere);                 star.transform.position = cartPosition;             }             else             {                 i--;             }         }     }      // Update is called once per frame     void Update()     {              } }  What this is supposed to do is generate 300 "stars" within the maximumRadius of 100 that are separated by at least minDistBetweenStars. I haven't been able to figure out what's actually happening -- sometimes the check finds a collider and sometimes it doesn't.  It's almost as if the CheckSphere() check is happening before the stars get placed via the star.transform.position = cartPosition. I'm very new to Unity and appreciate the help.  Anyone have any idea what's going on? *edit: Some more information, I've tried the script in both 2020.1.12f1 and 2019.4.14f1 to no avail. I'm also aware that this will lead to an infinite loop if it can't find a placement.


Which books/videos do you recommend for astrophysics?

I love astrophysics, but I can't seem to have a proper introduction.


On reaching level 20, I was advised to 'start saving up' for Speeder training by a tutorial popup. And looking at my class skill trainer, high level abilities cost... well, they cost what seems to be an astounding amount of money to my low level self.  What's the most efficient way to earn lots of credits in The Old Republic?


I've been writing a little program for my mother, in which I have to display a list of prices based on the work they ask her to do. Since she needs all the decimals in the price I set the Cell Format on Excel to have 7 decimals. The problem is that debugging my program, when I go reading a cell with a price in it, it adds several zeros after the number which are not actually written on the cell. I can't understand what's going on and I'm using OpenOffice saving the file as an Excel 97/2003 file, so as "listino.xls". Here's the code I'm using to get the title of the work and the price:  public Lavorazione[] creaLavorazioni(Lavorazione[] lavorazioni){ //create Work      char[] stringa = new char[8];     double prezzo = 0;     String prezzostringa = "";      for(int righe=1;righe<workbookR.getSheet(0).getRows();righe++){ //until the rows of //the excel table end          try{             lavorazioni[righe-1].setLavorazione(l.LeggiCella(listino, 0, righe));             stringa = l.LeggiCella(listino, 2, righe).toCharArray();             for(int i=0;i<stringa.length;i++){ //getting number and switching "," //with "."                 if(stringa[i]==',')                     stringa[i]='.';                  prezzostringa += stringa[i]; //Creating the price string             }              prezzostringa=prezzostringa.substring(0, 8); // deleting extra zeros, just //in case             prezzo = Double.parseDouble(prezzostringa); //casting to double             lavorazioni[righe-1].setPrezzo(prezzo); //setting in lavorazioni.prezzo          }catch(Exception e){             System.out.println("è successo qualcosa in creaLavorazioni!");         }         prezzostringa=""; //resetting for the next cycle     }      return lavorazioni; }   the class Lavorazione is made by me and it's this:   public final class Lavorazione {  private String lavorazione; //name of the work to do private double prezzo; //price of it  public Lavorazione(String lav, double costo){     this.setLavorazione(lav);     this.setPrezzo(costo); }  public String getLavorazione() {     return lavorazione; }  public void setLavorazione(String lavorazione) {     this.lavorazione = lavorazione; }  public double getPrezzo() {     return prezzo; }  public void setPrezzo(double prezzo) {     this.prezzo = prezzo; }   So it just has the name of the work and the relative price. In a few words, when there's "0,05423" in the cell, it writes "0.05423000000000001". Can anyone help me about this? Is using the java.util.Locale a good idea? If you need more info, ask me please.  EDIT: I'm using the jxl api.


What beamer environment is text within a frame?

I'm going crazy just trying to change the color of the text within a frame environment.  \begin{frame}[plain]   I want this text to be red!!! \end{frame}   I have tried almost every single environment listed on the .  {   %\usebackgroundtemplate{\includegraphics[width=\paperwidth]{dark_galaxy.jpg}}   \begin{frame}[plain]     \setbeamercolor{alerted text}{fg=red}     \setbeamercolor{background canvas}{fg=red}     \setbeamercolor{block body alerted}{fg=red}     \setbeamercolor{block body}{fg=red}     \setbeamercolor{block body example}{fg=red}     \setbeamercolor{block title}{fg=red,bg=blue}     \setbeamercolor{fine separation line}{}     \setbeamercolor{frametitle}{fg=red}     \setbeamercolor{item projected}{fg=red}     \setbeamercolor{normal text}{fg=red}     \setbeamercolor{section in sidebar}{fg=red}     \setbeamercolor{section in sidebar shaded}{fg=red}     \setbeamercolor{separation line}{fg=red}     \setbeamercolor{sidebar}{fg=red}     \setbeamercolor{structure}{fg=red}     \setbeamercolor{subsection in sidebar}{fg=red}     \setbeamercolor{subsection in sidebar shaded}{fg=red}     \setbeamercolor{title}{fg=red}     \setbeamercolor{titlelike}{fg=red}      Electromagnetic radiation from hydrogen gas in VIRGOHI 21 suggests it is     part of a system with a mass of \approximately $10^{11}$ solar masses.   \end{frame} }


I just blew almost all my money on a really cool lookin' ship. How do I regain solvency without spending a lot of time fiddling around in my inventory?  At the moment I've found a sequence of steps that'll turn 50 carbon and 100 Plutonium into ~5000 Units (by creating Suspension Fluid and then turning it into Electron Vapor). Are there better recipes or sequences of recipes I should look for? Or should I just drop the whole thing and go mine a particular mineral?


Lost badges, tags and flag weight after openID problem

For the last three days I've been unable to log in to any of the Stack Exchange sites.   I use MyOpenID and I've been having this similar problem:   I made the mistake of adding (so I thought) a Stack Exchange login (my email + password + the same username). However, I think I created a new one that conflicts to the openID user that I managed to get working again.  But, I lost all my badges and tags (most of the badges are returning (with today's date)), and also my flag weight is lost:     NOTE: This only happened on my SO account, all other accounts are ok!  What can I do to return to my old state? I just deleted the SE login and after several logouts am sure I have logged in with openID.  UPDATE: The tags are back. But I'm still missing two silver badges and one gold badge. I assume SO will "return" it as it did with the tags. Also, I also lost all my tag preferences. The flag weight, I can't be sure, I can't find it anywhere.  UPDATE 2: Some days have passed since this happened, and from what I understand, the badges came at the same time (probably the way SO tried to solve this), but I definitely lost my Fanatic gold badge, Enthusiast silver badge and Deputy silver badge (this one denotes the loss of the flag weight).  Is there an email I can write to, or some admin that can sort this, please?  UPDATE 3: The only thing that is missing is the Deputy silver badge (and so my flag weight), I'm now certain that I lost the flag weight and am in the process of "regaining" it by reviewing another 80 posts. It's not the best but I can live with that, because now I don't believe the flag weight + lost badge will return. By the way, each user can view their flag weight in their profile.


"System Program Problem Detected" at login

I keep getting the system report of system programs: the action is com.ubuntu.apport.apport-gtk-root.   Why is this happening? Should I authenticate it?   I haven't allowed it since I'm not sure what it is and don't have a clue. I just click close and it doesn't come back; it only happens when I boot or reboot.


Why is an open interval not a compact set?

I learned that every compact set is closed and bounded; and also that an open set is usually not compact.   How to show that a concrete open set, for example the interval $(0,1)$, is not compact? I tried to show that $(0,1)$ has no finite sub cover.


$f_{X,Y} \left( x, y \right) = 1\quad \text{for}\quad 0≤x≤1,\ 0≤y≤1 $ and $0$ otherwise.  How to calculate $P \left( |X − Y | ≤ 1/6 \right)$?


Looking to ask question on OCR tool recommendation - where would I ask this on Stack Overflow?

I'm looking to build a license plate detector, but I am struggling to get the last part of the process working i.e. a character classifier for each character I've segmented from the license plate.   If I would like to inquire on a Stack Exchange website on what the best possible tools to use for this would be, where would I ask, or is Stack Exchange the completely wrong place for this type of question (and if so which site could I use to ask this type of question)?


Ability to create questions with vote or comment or both disabled

I am sure that many questions are not posted because the user has a fear of downvoters. It is true, because many people give downvotes only because of a small grammar error, or a method of programming that they don't like, or because the user posted a question that has a similar one in another place, even if it asks more information than the another similar question.  But the most important case for that is the new users. Beginner programmers that don't really know how to write good code. The people don't understand that and just downvote and shout out "do not use css inline style on the html!!!" for example.  The question is the prejudice that users sometimes have. Having the option of disabling votes  would mean you will be not traumatized if your question is totally non-sense to other people.


Prove by induction that $3^{2n+3}+40n-27$ is divisible by 64 for all n in natural numbers

I cannot complete the third step of induction for this one. The assumption is $3^{2n+3}+40n-27=64k$, and when substituting for $n+1$ I obtain $3^{2n+5}+40n+13=64k$. I've tried factoring the expression, dividing, etc. but I cannot advance from here.


Can't open desktop folders on Ubuntu 18.04

The thing is that I decided to install Ubuntu 18.04 LTS (had 17.10 before) and everything was fine, I could open desktop folders. I don't know how, but some days ago suddenly I couldn't open theses folders by double clicking on them or even right clicking and trying to open as a new window. I can open these folders with Nautilus(default file browser) and can even delete them and some more options like rename (as double clicking on them at desktop) and can also open desktop files by double clicking. The problem is just with folders on desktop. I tried to look for a solution but nothing worked at the moment so I hope someone could help me with this. I am using GNOME desktop environment.  @ArchismanPanigrahi First i did a clean install and it worked fine but i started to install some gnome extensions and suddenly dunno with which one it doesnt work anymore. The thing is i disabled all the extensions and keep not working. I am running 18.074 with ComunityTheme but it doesnt work with normal enviroment. I wish this info can be useful for u, anything u need just comment, sorry for answering late but I was kinda bussy. Thanks  @DavidFoerster Yeah, i tryed to enter as guest user and the problem continues, i think it could be a nautilus problem maybe but was looking for info and tryed to reinstall, nothing worked at the moment. Its not a really serious problem but would like to know why this is happening, i just found one guy in Ubuntu Reddit who has exactly the same problem and no solution, i will try to solve this again because i was kinda bussy and didnt got time to continue. Anywway thx for your help and sorry for the late answer.  EDIT 1: Still no solution found, formatting would solve this but dont want to do this.  EDIT 2: Tryed to remove nautilus and use Nemo as main file browser and have the same problem so i dont think its a nautilus problem.  EDIT 3: I found this article and not sure if could be the answer for my question. If anyone knows comment, thanks.


Should I upgrade from a Canon 550D to a Canon 5D mark II?

I've been into photography for almost 7 years now and have been using the Canon 550D all along. I love it and have recently purchased a 1.4 lens which makes my photos even better. However, with my camera being really old and wanting my work to look better and more professional, I'm thinking of selling my Canon 550D upgrading to either a Canon5D mark II, or going mirrorless. I'm torn between wanting something lighter and easier to use and carry around, and crazy image quality.  Also, if I were to sell my used Canon 550D which works perfectly fine but looks used (a few scratches here and there), how much should I sell it for?  I appreciate all feedback and advice, thanks! :)


What is the correct watching order of Fullmetal Alchemist?

I have been recommended to watch Full Metal Alchemist. However, the person who recommended this series to me can't remember the correct order. After googling it, I'm confused as many people have posted different orders.  So what is the correct watching order of Fullmetal Alchemist?


Difference between "right of=" and "right=of" in PGF/TikZ

In the PGF/TikZ manual, sometimes I see the option right of=somenode instead of right=of somenode. They look very similar, but the effects are different.  The distance between nodes positioned with the latter option is boundary-to-boundary, as stated in the manual. However, with the first option, it seems that the distance is shorter. I couldn't find any explanation of the first option in the manual.  My question is: what is the difference between the two options? Is there any explanation in the manual that I missed?


When I was a kid in the early 80's I remember watching a tv show about a big spaceship flying through space. I think it had few episodes, and the story revolved around the lives inside the ship.   I think I remember someone having a crossbow as a weapon.  It's very vague. Does this ring a bell to someone? I'm sorry for not having further details, but I was 4 or 5 when I saw it.  Edit: The answer is effectively a duplicate but not the question, as I didn't recall so many details as the other user.  Thanks


Is there way to automatically calculate amount of figures, tables and appendices?  I found a way to see what pages have figures( ), but how to calculate the amount.


Scanner throwing NoSuchElementException on call to next()

I've taken a look at other questions about this exception, but it seems that the common problem is that the scanner is closed too soon, which could not be the case here. Here is my code, with a comment above the problem line:      public void windowOpened(WindowEvent arg0) {      Scanner input = null;      try {         input = new Scanner(new File("/home/brian/workspace/Color Sampler/src/Data.txt"));     } catch (FileNotFoundException e) {         System.exit(1);     }      int i = 0;     int nR, nG, nB;     String nName;     while(input.hasNextLine())     {         // These lines are throwing the exception         nName = input.next();         nR = input.nextInt();         nG = input.nextInt();         nB = input.nextInt();          ColorSampler.colors[i] = new myColor(nName, nR, nG, nB);           i++;     }      ColorSampler.currentColor = ColorSampler.colors[0];     System.out.println(ColorSampler.currentColor.red);  }   Here is the exception I am getting:  Exception in thread "AWT-EventQueue-1" java.util.NoSuchElementException at java.util.Scanner.throwFor(Scanner.java:855) at java.util.Scanner.next(Scanner.java:1364) at WindowDestroyer.windowOpened(WindowDestroyer.java:57) at java.awt.Window.processWindowEvent(Window.java:1972) at javax.swing.JFrame.processWindowEvent(JFrame.java:290) at java.awt.Window.processEvent(Window.java:1933) at java.awt.Component.dispatchEventImpl(Component.java:4649) at java.awt.Container.dispatchEventImpl(Container.java:2103) at java.awt.Window.dispatchEventImpl(Window.java:2588) at java.awt.Component.dispatchEvent(Component.java:4475) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:675) at java.awt.EventQueue.access$300(EventQueue.java:96) at java.awt.EventQueue$2.run(EventQueue.java:634) at java.awt.EventQueue$2.run(EventQueue.java:632) at java.security.AccessController.doPrivileged(Native Method) at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:108) at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:119) at java.awt.EventQueue$3.run(EventQueue.java:648) at java.awt.EventQueue$3.run(EventQueue.java:646) at java.security.AccessController.doPrivileged(Native Method) at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:108) at java.awt.EventQueue.dispatchEvent(EventQueue.java:645) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:275) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:200) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:190) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:185) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:177) at java.awt.EventDispatchThread.run(EventDispatchThread.java:138)   I cannot figure out what would be the problem here. Can someone help?


I am trying to traverse a 2d array with a nested for loop, and it has different values when I graph it, but when I try to access the data, it the elements are all the same. I have tried different styles of for loops but get the same errors. This is more of an error that I don't understand coming from Java.  predicted_values = 2*[2*[0]] #  number of lines *[ number of data points *[0]]  for row in predicted_values:      #last given price     row[0] = adj_close[len(adj_close)-1]       for index in xrange(1,len(row)):          random_float_0_1 = random.random()         drift = meanPDR -variance/2         random_offset = standard_deviation*norm.ppf(random_float_0_1)         t = drift + random_offset         predicted_stock_price = row[index-1]*math.exp(t)         row[index] = predicted_stock_price         print predicted_values      plt.plot(range(0,len(row)),row)   This outputs  [[152.186905, 149.88609120889242], [152.186905, 149.88609120889242]] [[152.186905, 151.0754945683822], [152.186905, 151.0754945683822]]   when I want it to output  [[152.186905, 149.88609120889242], [152.186905, 0]] [[152.186905, 149.88609120889242], [152.186905, 151.0754945683822]]   What happened to overwrite the previous data that it shouldn't have access to.


Badge for editing a closed question and getting it re-opened

I recently had  that promptly got closed. After a meta discussion, a user made a very good edit, after which the question was re-opened and now (at the time this post was made) has 11 upvotes.  So what I wanted to propose is the possibility of a badge that gets awarded for editing a closed question and causing it to be re-opened. This would be a good way to encourage people to try to salvage closed questions that have the potential for improvement. Closed questions getting improved and re-opened no doubt leaves a positive impression on new users, and gives lets them see firsthand exactly what was wrong with their question (and what was right with it).  I recognize that there are more things to take into consideration here. Particularly, how can we be certain that a particular edit is the cause of it being re-opened? For this I have a few ideas:   Perhaps it can be awarded to the most recent edit. I recognize that this has the potential for "gaming" in that a person can see that a post is about to be re-opened and make an inconseqential edit in order to earn the badge. Maybe it can be awarded to the most  recent edit before the first re-open vote? Another idea which may be a bit more fair is this: maybe it should only be awarded if there has only been one edit to the post before the first vote to re-open. This is more fair, but of course it has the problem that it will at times fail to award the badge when it was deserved (i.e. when someone makes a great edit that salvaged the question, but someone else just made a simple grammar edit, it will cause the former person's edit not to be recognized).   This is just something I wanted to throw out there. Since this is just an idea, I'll just tag it as discussion instead of feature request.


Is it possible to detect a photon without intercepting it?

I am a little bit confused about photon particle/wave duality. Do we have to interact with photon to detect it? Or without interacting photon, only by its wave nature, can we detect the existence of a photon. Consider the following image:  Can detector2 at a sufficient distance, detect the moving photon in a way?


When does almost everywhere convergence imply convergence in measure?

Let $f_n$ be a sequence of measurable functions on a finite measure space. Is it true that   If every subsequence of $\{f_n\}$ has a subsequence which converge to $f$ almost everywhere, then  $f_n$ converges to $f$ in measure?  I have proved the converse of this statement, but problem says it is if and only if statement. Thanks in advance for any help!


Gravitational field strength inside the Earth

please could someone give me a relatively straight forward answer why the gravitational field strength follows a straight line (linear) relationship with distance from the center of the Earth but when you get to the surface it follows a 1/r^2 relationship?


Several times in the movie, Cobb says that no one should touch your totem, which would otherwise lose its ability to tell you if you're in a dream or not.    I understand, there is no "magical" ability in the totems. Just a way they are done/built, how their owner feels them so that you're the only one knowing how they should behave in reality and in dreams.  The other people wanting to trap you in a dream would then not be able to recreate all these details, which will then help you know if you're in a dream or not.    Concerning Cobb's totem, the top: it was Mal's totem, before being Cobb's totem. Then Saito also plays with it near the end of the movie. Several people touched it then and can know how it feels, even if they don't know the forever-spinning thing.        But Cobb also tells to Ariadne during the movie the special ability of the forever-spinning of the top in dreams. Ariadne could, mixing this with the information of people having touched the totem, recreate this in a dream and then fool Cobb.  As it seems she wants to help him, she knows all that, as well as his after-work dream sessions, she could have built a dream to trap him and having the top falling in the dream, having Cobb thinking he's in reality. In particular, the end could be a dream with Ariadne influencing the top's spinning.   At the end, is the top's spinning a reliable fact to know if he's dreaming or not?


Delete/remove orphaned users and their schema from server/database

I'm new to the role of being a SQL Server DBA for SQL Server 2008 R2.  I need help on how to find out orphaned users in SQL Server and how to delete/remove the orphaned users and their corresponding schema from the database.  Please provide a step by step solution.


How would you show that field automorphisms fix prime subfields?

Suppose $K$ is a prime subfield of $E$, then if $\phi$ is an automorphism from $E$ to $E$, we have for all $x \in K$, $\phi(x) = x$.   I feel like this is just the definition of a field automorphism, but my book says this should be proven as an exercise.


I have been trying to create a grouped overlay bar chart in latex using pgfplots, much like this one (not actually mine, found randomly on Google):    What I'm trying to achieve is not a stacked bar chart, but an overlay bar chart where all bars start at 0, such that taller bars appear "behind" smaller bars. With pgfplots, it seems quite easy to create bar charts, and to group bars together, but creating grouped overlay bar charts seems to be much more difficult.  Is there a way to create such charts in latex? (not necessarily using pgfplots)


How to restrict/cut power output to a USB client?

...or, how not to charge my phone when I'm using it as a GSM modem in USB tether mode?  I can use it as WiFi tether modem, but it wastes battery both of the netbook it supplies connectivity to, and on the phone side. In USB tether mode I would avoid the power-hungry WiFi connection, but instead the phone wrecks the netbook battery by charging from it. I'd like to be able to maintain the data connection while disabling or restricting the current fed over the power lines; let the phone and the netbook use their own batteries without draining each other.  I'm using Kubuntu 14.10 but any system solution is okay, I'm sure I'd be able to adapt it. Even hardware solutions would be okay - cut the power line in the USB cable or solder a large resistor in maybe? Would that work?


How to De-standardize coefficients from multiple linear regression?

I have a typical linear regression model: Y = B0 + B1*X1 + B2*X2  where B0, B1 and B2 are the regression coefficients which I solve for.  Before I do any regression modeling, I standardize the predictor variables X1 and X2. I also standardize the dependent(outcome) variable Y.  X1_standardized = (X1 - X1_mean) / X1_std X2_standardized = (X2 - X2_mean) / X2_std Y_standardized = (y - y_mean) / y_std  I would like to use the standardized values for my regression, however, to improve interpretation, I would like to revert (or de-standardize) the beta coefficients after solving for them.  How can I do this?


How can I share a helpful solution with the Community as my first post?

I just discovered a significant updated solution for the following topic:    I feel so compelled to share it, but this would be my first post.    How can I go about commenting to the topic or starting my own topic.  The issue has been alternate row coloring in a tablix.  An exhausted topic, but I had the issue of alternate row shading where the row group was sorted Z-A.  Using the Code.AlternateColor from the comments, I was able to achieve alternate row coloring on a sorted table and since I spent a lot of time trying to find the solution and realizing so many others have the same issue, I want to share.  Let me know the best way to share my solution (without a question really).


How to make some file that contains crucial data protected? For instance, suppose I have some files that are important, is there any method or strategy to make these kind of file more protected on Ubuntu? I even want to make some files ask for a password whenever someone tries to open it. Does it affect the version of Ubuntu in terms of security policy? May I use any encryption algorithm externally? Regards.


Error while giving values in following way

I am getting error on following lines " Type mismatch: cannot convert from int to short"   short a; a=09;   but not on   a=9;   why is it so.


I recently installed eclipse but its not starting when i enter command "eclipse" on terminal. I am pasting a log, Kindly review it and suggest solution to fix the problem


How do I disable Safari's Show All Tabs gesture?

Safari's Show All Tabs view is pretty useless, it only shows one tab at a time and is fairly easy to trigger with an accidental pinch gesture. How do I turn it off (as least for the pinch gesture)?


I created a 2G partition like this with fdisk:  Command (m for help): n Partition type:    p   primary (1 primary, 0 extended, 3 free)    e   extended Select (default p): p Partition number (2-4, default 2):  First sector (4196352-16777215, default 4196352):  Using default value 4196352 Last sector, +sectors or +size{K,M,G} (4196352-16777215, default 16777215): +2G Partition 2 of type Linux and of size 2 GiB is set  Command (m for help): w The partition table has been altered!   But if I check the size (again with fdisk) it seems to be    fdisk /dev/sdb Welcome to fdisk (util-linux 2.23.2).  Changes will remain in memory only, until you decide to write them. Be careful before using the write command.   Command (m for help): p  Disk /dev/sdb: 8589 MB, 8589934592 bytes, 16777216 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0xe82746a5     Device Boot      Start         End      Blocks   Id  System /dev/sdb1            2048     4196351     2097152   83  Linux /dev/sdb2         4196352     8390655     2097152   83  Linux   blockdev --getbsz /dev/sdb2 4096   Then double-checking things:  echo "2097152*4096/1024/1024/1024" | bc 8   (blocks * bytes / 1024^3 should give GB right?) which implies an 8GB partition.  How am I calculating this wrong?


What do the different colours of locks all mean? There are green ones purple ones and I am really confused what they all mean! There is nothing in the help section or anywhere online, am I just a bit stupid?


Why '$' in regex isn't working as expected in debian?

I have the following file: cat regex16.txt gives     foo bar baz     bar foo baz     baz foo bar     bar baz foo     foo baz bar     baz bar foo  I want to grep only the lines which end with bar. So, I am using $ symbol to grep for bar. But, I don't get any results. What am I doing wrong here? grep '.*bar$' regex16.txt  Why bar$ isn't working here?


Disabled recursive DNS. How to configure Split DNS?

I have a Windows Server 2008 R2 server which is hosting a public website. I recently deactivated "DNS Recursion" for security options trough the :  In the properties of my DNS server in the "Advanced" tab under server options I check the option: Disable recursion.  Now I have the problem, that DNS Names are not resolved locally. So I cannot open google.com or microsoft.com nor anything else.  Now I found out that I have to configure a split DNS configuration, such that I have:   One Zone which only answers lokal DNS queries and allows recursion One Zone which only answers external DNS queries and does not allow recursion.   My current setup looks like this:    I have a server named WIN-FOOBAR and a domain named foo.bar.com, so there are two entries _msdcs.foo.bar.com and foo.bar.com.  Now I have two questions:   If I disable recursion in the server options (e.g. in the parent node named WIN-FOOBAR), then how can I have two zones where one allows recursion and one that does not? The Forward-Lookupzone entry is a child node of WIN-FOOBAR. But I did not see an option to disable recursion for individual zones. How should I name the second zone, which is used internally? The current zone is foo.bar.com, can I create a second zone and also name it foo.bar.com as well or must it be named differently? If I name it for example foo.local, can it still resolve queries to foo.bar.com?


How to find cause of high kernel_task cpu usage?

Occasionally my machine will have a kernel_task instance max out the CPU:    This can last from minutes to sometimes hours. The machine is effectively unusable in this state. Restarting doesn't help; a new kernel_task pops up again until it finishes whatever it's doing.  How can I find out what this process is doing?


How to show if $H,K$ are normal subgroups in a group $G$ then $[H,K] \leq H \cap K$.  Here $[H,K]$ is the commutator subgroup.  I have tried to start it but instantly failed:   I want to show firstly that $[H,K]\subseteq H \cap K$ but I don't understand what an arbitrary element of $[H,K]$ would even look like so I have something to work on.  I thought it could look something like $h^{-1}k^{-1}hk$ but then I thought that we are working with the smallest subgroup containing elements of this form but that might not be what the actual elements are?  Could anyone help?


prototypical inheritance in javascript ,cloning property

how can I achieve below things in javascript  var parent = {   a: 5,   b: 6 }  var child = parent; console.log(child.b); // 6  //now if I change the value of b parent.b = 7  console.log(parent.b); //7 console.log(child.b); //7   //but I want to preserve the previous value of the object property it should not change now.it should show 6 instead of 7 in case of console.log(child.b)


What is taking up so much space on my disk, beside the filesystem?

I have only one disk in my computer, a 80 GB SSD. It is formatted as a single ext4 partition (no swap), and all the usual folders are installed on it (I keep lots of data on external media, but /home and all the rest is on the SSD).   Today I booted it and I got a message that the drive is full. I opened Disk Usage Analyzer to look at what takes up space. It insists that 67.8 GB of the disk are used, and that / is taking up 36.4 GB. Which leads to the question, where are the missing 30 GB, if not on the file system?!    Just to have a comparison, I added up all the sizes of all readable folders listed in Nautilus as subfolders of / (including the hidden ones). I got 20.9 GB. Trash was unreadable, but I know it has 16.2 GB, so the sum is 36.1 GB, around the same as what Disk Usage Analyzer is reporting. There were some system folders which were unreadable, like proc, but I doubt that they add up to 30 GB - else it wouldn't be possible to install Ubuntu on small disks, and I've seen it run on 2.5 GB. I think they must be the 0.3 GB difference between my calculation and the Disk Usage Analyzer's report.   So I'd like to know, what is eating up these 30 GB and how do I get it to free them?     Edit with answers to CYREX's questions   Booted from Ubuntu 10.10 64-bit live CD (same as my system).  fsck result:   root@ubuntu:~# fsck /dev/sda1 fsck from util-linux-ng 2.17.2 e2fsck 1.41.12 (17-May-2010) /dev/sda1: clean, 265956/4890624 files, 18073343/19537408 blocks  Booted from the SSD. Emptied the trash, and the 16 GB from there are now free. The 30 GB are still missing.    I'm not experienced enough to know what counts as weird in a log. Here are my messages log and my syslog since last boot. Maybe you can find something in them:       Here it got really strange. I plugged in an external 500 GB HDD. Disk Usage Analyzer overreported the available space, then showed space missing (76 GB used, but only 24 in folders).      Booted again from the LiveCD, started the Disk Usage Analyzer from it and got the same results as from the installed Ubuntu, within 1-2 GB.   Edit with answer to CodeMonk:  That would have been a nice solution, but the partition is really 80 GB - I mean 74 GB + marketing "error", anyway the whole disk is formatted. It also shows that over 50 GB are used, so where are the 30 GB if not in files and folders?    GParted also reports the correct size of the external HDD.


MikTeX package manager unable to download any packages

I used to be able to download packages but recently I have been unable to do so for quite sometime now.  It gives the message:  get proxy host by name failed in tcp_connect()   I don't remember doing anything different except that I have moved from another location and I am using another broadband connect, but I am not sure if it is related to this problem.


Can i use intervalometer to engage continuous shooting?

Can i use intervalometer to engage continuous shooting (setting continuous with speed ~5fps on camera instead of bulb) for 20 seconds and delay/timer of few minutes ? (with sony a6000)


I'm creating a mobile app in Ionic (which uses Angular). I've set up a D8.3-dev BE which will hold the users and their data.  I've figured out how to register as an anonymous user (this is why I'm using D8.3-dev because this functionality is introduced here) and wrote a blog post about it ().  Logging in also works after I registered a user.  This is how I login:    /*    * Login User with username and password.    */   login: function (email, password) {      var defer = $q.defer();      $http({       method: 'POST',       url: config.endpoint + '/user/login?_format=json',       data: {         name: email,         pass: password       },     })       .success(function (data, status, headers, config) {          // Store the CSRF token.         localStorage.set('csrf_token', data.csrf_token);          // Store the Logout token         localStorage.set('logout_token', data.logout_token);          // Set the user object.         localStorage.setObject('user', data.current_user);          defer.resolve(data);       })       .error(function (data, status, headers, config) {         defer.reject(data);       });      return defer.promise;   },   When logging in I receive the following:  current user object, a csrf_token and a logout_token.  When I use these tokens to logout (I tried a lot of different ways already:    /*    * Logout User.    */   logout: function () {      var defer = $q.defer();      $http({       method: 'POST',       url: config.endpoint + '/user/logout?_format=json&token=' + localStorage.get('csrf_token'),       dataType: 'json',     })       .success(function (data, status, headers, config) {         defer.resolve(data);          // Go to the login page.         $state.go("login");       })       .error(function (data, status, headers, config) {         defer.reject(data);       });      return defer.promise;   },   I keep getting the following error:  {"message":"\u0027csrf_token\u0027 URL query argument is invalid."}   So it seems the crsf_token I use from logging in isn't correct.  What am I doing wrong or overseeing here?  EDIT: after testing a lot and trying it seems like I need to use get. I use this code now for logout but I still get a 403:    /*    * Logout User.    */   logout: function () {      var defer = $q.defer();      $http({       method: 'GET',       url: config.endpoint + '/user/logout?_format=json',       headers: {         'X-CSRF-Token': localStorage.get('csrf_token'),         'Authorization': 'Basic xxxxxxxxx',       },     })       .success(function (data, status, headers, config) {         defer.resolve(data);       })       .error(function (data, status, headers, config) {         defer.reject(data);       });      return defer.promise;   },   Here is what the Drupal 8.3-dev BE returns, it seems like it recognizes the user I want to log out but it's still throwing the 403.


Confidence interval syntax in frequentist probability

Let $\theta$ be an unknown population characteristic (say average height).  A confidence interval written as $P(\hat \theta - \delta < \theta < \hat \theta + \delta) = 1 - \alpha$ makes perfect sense as $\hat \theta$ and $\delta$ are random variables.  If we do, however, write the result, say for estimated $\hat \theta = 180$, $\delta = 13$, does the following syntax (which is the standard in the books I'm studying) make sense, since the numbers are constant and $\theta$ is an unkown characteristic (and therefore a constant in frequentist probability)?  $P(167 < \theta < 193) = 0.95$


Policy concerning unilateral closing of questions?

Is there a policy or guidance concerning criteria moderators should apply before unilaterally closing questions?  Obviously, if a question is blatantly off-topic or has another problem the moderator would be justified in closing it.  However, in a few rare cases I have seen moderators unilaterally closing questions with no vote even though the question was potentially valid. For example, in one case the moderator commented "I'm not sure this is on topic." So, the moderator explicitly said they were unsure whether it was a valid question, nevertheless they closed the topic without allowing a vote.


How to install VLC Player on the original iPad (iOS 5.1.1)?

My friend has the original iPad that runs iOS 5.1.1 and can't be updated any further. Very few apps these days are compatible with that version of iOS. The new version of VLC in the App Store requires iOS 7.  What I thought I'd do is get an old version of the .ipa for VLC that's compatible with iOS 5.1.1. I have a computer with iTunes that I wonder if I can use to transfer it to the iPad.   Are some old versions of VLC compatible with iOS 5.1.1? If yes, what's the latest VLC version that's compatible? Where can I get such .ipa files? Do I have to jailbreak the iPad in order to install such downloaded files, or can I do it without jailbreaking?


Windows RDP Server farm redirection stops working

We have a RDP Server farm based on Window 2008R2 servers with DNS round robin. That is, people make a connection to "myfarmname", which first takes them to the ip of some "farmmemberX.mydomain.local" and then they are redirected to some "farmmemberY.mydomain.com" according to load. That's also how everything workd until yesterday. As of today, most users experience problems and cannot connect to the farm, usually with an error message like this (translated from German):  Remote desktop connection cannot connect to remote computer. From remote computer "myfarmname", with which you want to make a connection, you are redirected to remote computer "farmmemberX.mydomain.local". It cannot be verified if both remote computers belong to the same remote desktop server farm. You must use the farm name, not the computer name, if you want to mak a connection to a remote desktop server farm. Contact a network administrator to obtain support if you use a RDP connection that was prepared by the administrator. If yo want to connect with a specific farm member, use "mstsc /admin"  As you can see, I do use the farm name - but I still fail, with settings that worked yesterday. Changes are possibly updates and stuff, but nothing regarding configurations. How can I correct this misbehaviour? My only workaround currently is to provoke the above "myfarmname"/"farmmemberX" error and then try a connect to farmmemberX (which apparently is the currently preferred target) and then connect diretly to farmmemberX.  Overview of settings of the RDP servers: Tab Remote desktop connection broker: Server usage: farm member Remote desktop connection broker: MYBROKER Farm name: myfarmname  RDP tcp: Security: Negotiate Encrpytion: client compatible Allow only NLA: not checked certificate: valid, issued from internal CA


Currently, when I want to reopen a question via my mobile device, I have to go to Safari or other browser app to do this.  Is it possible to add an option to vote to reopen via the app itself?


Classic (high ick-factor) New Wave story about humans living with insectoid aliens

This story begins with a boy and his sister living with their parents in the home of their owner/protector, a large insectoid alien. There is a commotion outside the door, which turns out to be a human male in excruciating pain. As it turns out, the aliens have brought some humans from Earth to their own planet. I don't remember if the humans were the only survivors of a destroyed Earth, or if Earth was still there but oblivious to what the aliens had done. That doesn't matter, anyway, because the humans are there for the purpose of using their bodies as living hosts for the aliens' eggs. The man's owner (not the kids' owner) has neglected her charge's progression, and now the eggs have hatched and are devouring him from within. The kids' owner removes the hatchlings and saves the man's life (but probably not mental health). As a result, the alien feels it necessary to sit the boy down and explain the Birds and Bees to him. She delivers a rather mealymouthed lecture about how she would never neglect them like that, the task at hand is an honor and slaveryaintsobad yaddayaddayadda.... But it's now time for the alien to lay its own eggs, and has been considering the boy's sister for the job of host.  Upon hearing this, the boy volunteers to be the host, in order to spare his sister. There's a terrifying final scene as the alien lays its eggs.  I have at least two anthologies that contain this story. I just can't find either one, or remember the title or (IIRC well-known American) author. This is a story that I could have sworn appeared in one of the legendary New Wave Dangerous Visions anthologies. Much later (late 2000s), I immediately recognized it in a later (single author) anthology. I proposed it as an answer to  a while back, and would have submitted an answer if only I could have remembered the title, or pulled the right book out of a box. And it's been bugging me ever since.


Am I doing something wrong or do I need a new lens? [DOF and focal length]

I'm new to photography and I can't get a nice DOF. I read up on all the technicalities that involve  DOF and I still can't get it right.   For example, if you take a picture very close to an object, zoomed out,  and then move further back and zoom in would the pictures show the same DOF given the aperture was adjusted?    With my kit lens (EF-S 18-55mm 1:3.5-5.6 IS) I can't change the aperture below f/5.6 when zoomed in (or f/3.5 when zoomed out) so I cannot create a nice DOF. Also, my kit lens has its sweet spot around f/7.1 and since I want my pictures to be sharp I want to shoot with that aperture.   So my basic questions are:   Do I need a new lens with a maximum wider aperture to achieve the outcome I want?   Does focal length really influence DOF? If so, why can't I change DOF by getting closer to the object? Am I doing something wrong?   I'm interested in street (especailly at night)/landscape and animal photography and my body is a Canon E550D RebelT2i (crop factor 1.6).   Thank you in advance!


What do I scale up on a virtual server to take load off the CPU while uploading big files?

I have a small photography portfolio website running on Ubuntu. It's a Digital Ocean  with the following parameters:   512RAM memory  1 vCPU 20GB SSD disk 1TB transfer   This setup is sufficient for my needs when it comes to handling user traffic, which is very low. However, as the website features photos, I have an Admin Panel logic for creating new galleries - and the uploading part goes heavy on the server.   The files I upload are weight approx. 8MB; the photos are scaled down and saved locally in multiple (5) sizes. At times, there are 20 photos chosen for a gallery, uploaded asynchronously 3 at a time.  I noticed that when the upload is running, the CPU usage on the host jumps from 20 to 100%, while the memory usage stays at around 50-60%. Disk I/O also peaks. The upload process always succeeds but it's very slow and I have no clue what to enhance to speed it up.  I'm not good at this, so I'm looking for any insights on why would the upload process put so much load on the CPU and what should I scale up to increase the performance of the server and decrease the photos upload time.  Any ideas?


What am I doing when I separate the variables of a differential equation?

I see an equation like this:  $$y\frac{\textrm{d}y}{\textrm{d}x} = e^x$$  and solve it by "separating variables" like this:  $$y\textrm{d}y = e^x\textrm{d}x$$ $$\int y\textrm{d}y = \int e^x\textrm{d}x$$ $$y^2/2  = e^x + c$$  What am I doing when I solve an equation this way?  Because $\textrm{d}y/\textrm{d}x$ actually means  $$\lim_{\Delta x \to 0} \frac{\Delta y}{\Delta x}$$  they are not really separate entities I can multiply around algebraically.    I can check the solution when I'm done this procedure, and I've never run into problems with it.  Nonetheless, what is the justification behind it?  What I thought of to do in this particular case is write  $$\int y \frac{\textrm{d}y}{\textrm{d}x}\textrm{d}x = \int e^x\textrm{d}x$$ $$\int \frac{\textrm{d}}{\textrm{d}x}(y^2/2)\textrm{d}x = e^x + c$$  then by the fundamental theorem of calculus  $$y^2/2 = e^x + c$$  Is this correct?  Will such a procedure work every time I can find a way to separate variables?


Zero divisors in polynomial in a commutative ring

There's an exercise in Herstein marked as very hard     Let $R$ be a commutative ring. If $q(x) \in R[x]$ be a zero divisor in $R[x]$, then if $\displaystyle q(x) = \sum_{0 \leq i \leq k} a_i x^i$, prove there's $b \in R$ such that for all $0 \leq i \leq k$, we have $ba_i = 0_R$    Now how I am supposed to solve this ?  I know that I'm supposed to prove how much I have worked by myself before asking for help, but I tried for more than two hours but still can't even solve the case when $\text{deg}[q] = 1$


conditional expectation with two signals

I am quite embarrassed to ask you this question but I am stuck.  I have to compute the following conditional expectation : $E[\theta|x_i,y]$. I know how to compute the basic E[X|Y]E[X|Y] but I definitely do not know how to compute E[X|Y,Z]E[X|Y,Z]. Can someone please orient for the first step?  with   $\theta\sim N(0,\sigma_\theta^2)$  $y=\theta+\eta$, where $\eta\sim N(0,\sigma_\eta^2)$  $x_i=\theta+\epsilon_i$, where $\epsilon_i \sim N(0,\sigma_\epsilon^2)$  I know the result is $$E[\theta|x_i,y]=\frac{\sigma_\eta^2}{\sigma_\epsilon^2+\sigma_\eta^2}(x_t-y)+y$$ but I cannot find it.  I know how to compute the basic $E[X|Y]$ but I definitely do not know how to compute $E[X|Y,Z]$. Can someone please orient for the first step?   Thank you


Is it possible to obtain a Master's degree without Bachelor's degree?

I have worked as translator for more than seven years in the industry. I have a background in cuisine for more than ten years. Now I would like to add an graduate degree related to Tourism, Hotel and Event Management to my professional experience.  Can I enroll in such a masters program without first acquiring a Bachelors degree?


How convergence relates to equivalence of norms

Let $X$ be a normed linear space with two norms $||\cdot||_1$ and $||\cdot||_2$. Prove or disprove that this statements are equivalent:   $||\cdot||_1$ and $||\cdot||_2$ are equivalent, $\{x_n\}$ converges in $||\cdot||_1$ iff $\{x_n\}$ converges in $||\cdot||_2\;\; $   $\forall \{x_n\}\in X$   The first implies the second trivially because of equivalence of topologies. But it implies something more: sequence converges to the same element in both norms. But I don't have such condition.  Is this a necessary condition to converge to the same in both norms, or this is just a consequent of "if and only if" in the statement of convergence, or there is a example disproving the equivalence?


[5]     i  If she beats him he’ll claim she cheated.    [non-deictic past]     ii If you eat any more you’ll say you don’t want any tea.[non-deictic present]      The preterite and present tense inflections on cheat and do indicate that Tr is respectively anterior to and simultaneous with To, but here  To is clearly not Td. The time of the (possible) cheating is not anterior to the time of my uttering [5i], but to the time of his (possibly) making a claim of cheating.                       — The Cambridge Grammar of the English Language, p126   I can understand To (time of orientation = utterance time), yet don’t get what the ‘deictic time (Td)’ is. Would you let me know the Td?


Capitalization of bpm/BPM meaning beats per minute

The Oxford English Dictionary defines "bpm" as an abbreviation of "beats per minute" and gives the example:     a pulse rate of 40 bpm   Is there an explanation for the curious feature that this abbreviation is set in lowercase?


How can I host a website on a dynamically-assigned IP address?

I recently upgraded my internet to the point that it is much faster and more reliable than my current webhost. I would like to move my current domain to be hosted at home, but my IP address is dynamic. As far as I know, I only get a new IP when I restart my modem and or router (which is almost never) or when cable one (my ISP) pushes out a firmware update (rarely).  There are a few ways I can see doing this:   Convince my ISP to give me a static IP Assign my router my current IP to force a static IP (which might work?) Set my DNS record to my current IP address and update it on the rare occasions that it changes.   Obviously I'm hoping that the first one works, but I don't want to pay a lot of extra money (if that's what it takes) to get a static IP address.  Which of these options will work most reliably?


A partition is necessary before installing ubuntu on windows 7?

Im trying to install Ubuntu on my PC that runs Windows 7. Do I need to make a partition before installation?


Short story about robots powered by air pressure

The story was about a robot/android made of brass and powered by air. His entire world, all the people in it, was built the same way. He was fascinated by their brain analog which, by self-examination and experimentation, he discovers is a complex set of tiny, thin brass wafers with patterns on them that constantly moved and intermeshed due to air pressure. All of the beings in this world needed to recharge their air pressure or they would die. The space below their world is a large pressurized air bladder that is slowing equalizing with the upper world.


Idiom meaning that something doesn't happen often, but happens more than needed when it does?

I remember that there was an idiom that describes something that doesn't happen often, but happens more than needed when it finally does.  Hypothetical scenario that could be described by such an idiom: Let's say that I spend the whole year asking for a Playstation 4. When Christmas comes around three family members offer me the same console.


is it possible with newtonian gravity to throw something (which has no on-board propulsion) so that it will orbit the earth without colliding with it(friction is not present)? my intuition tells me that no, because all closed newtonian orbits are periodic so that if I throw some thing it will eventually come back to earth. But I can't seem to show it with the math. Any help would be appreciated.


Filter Flames are disabled in photoshop CC 2017

Just starting out with photoshop CC 2017 and I am trying to add flame in my image but Filter<Render<Flame this option is not active, after a lots of efforts and time I am not able to activate them and couldn't find what's the problem behind of it. Can anybody guide me how can I activate them?


Am I the only one for whom SO has became the rubber ducky?

Not seeking answers, just drawing attention to somewhat positive effect of StackOverflow I have noticed recently.  Today, for some fifth time in a row I didn't post a question I started typing. Once again I found my answer while halfway through.  The process goes like this:   State my problems. State tools available for solving them that are at my disposal, and the constraints. State possible solutions and why they are not viable. Discuss why they are not viable; how each obstacle is insurmountable given accessible tools, constraints and my knowledge, or how standard solutions to them will not work. Find one with standard solutions that will work. Enjoy my solution, cancel posting the question and just proceed with my work.   Rubber ducky to be efficient must be believable. You must overcome the suspension of belief when explaining things to the ducky. You must believe the ducky can answer and help. A real rubber ducky doesn't really cut it for me, but SO works quite well!


I'd like to have an advice from you. I was thinking about studying for the exam of general relativity from Landau II: theory of fields. I already studied mechanics and fluid dynamics from Landau and I loved those books in every aspect. I couldn't find a better book in these two topics so I have to give credit to Landau about general relativity too.   The problem here is that our professor strongly suggested other textbooks saying that we could study from Landau but it would be way too hard with respect to books like:  Bernard F. Schutz, A first course in general relativity  S. Weinberg, Gravitation and Cosmology  And once we learn relativity from those we may approach the study of Landau, but only after having already studied it. And at that point it would be almost pointless to restudy it from nothing since you already know the topic.  I'd like an advice from people who knows at least one of these books. How they are? Is Landau really too hard or it's just the usual representation people make about his books, confusing the concept of being too difficult with the concept of "it forces you to think"? As I said I love the 2 books of Landau I studied from so I'd like to have very good reason not to study relativity form his text.   Ah, notation is not a problem.  Edit: It isn't a duplicate. I explicitly asked about Landau's book which is quoted twice in that post. And only one answer says something about it. Plus there's no confront of Landau with other books. The main point here is Landau's book which is not there


Possible Duplicate:          I have seen a lot of backlash in internet media against people using the word literally to mean something not literal. Something like "he was literally as big as a house" to mean someone was very big I think this comic sums up the anti literal movement well   Is this actually grammatically incorrect or can the word "literally" be a hyperbole strengthening a metaphor?


how to add more white space over symbols in a nested fraction?

I am writing some complicated formulas that involve several layers of fractions.  Example:  \begin{displaymath} \scalebox{2.5}[3]% {$ 1+\frac{1^2}{2+\frac{3^2}{2+\frac{5^2}{2+\frac{7^2}{2+\frac{9^2}{2+\cdots}}}}} $} \end{displaymath}   but the visual result, although readable, could be improved with some white space over all the squared odd terms. How would I achieve that? The vertical scaling of \scalebox does not help since I guess that the spacing between the fraction line and the exponent under it is too close to zero.


I've been trying to use the Olympiad package for Asymptote on my Mac to use in TexShop (I'm working with pdfTeX). I just tried to put import olympiad; in front of my code, but it gives an error:  Processing file error: could not load module 'olympiad'   On the following link's post, it says I have to install the olympiad package somehow? I'm fairly new to Asymptote in TeXShop, so I don't know how I should install/download/set up the package.    How do I use the package? All I want to do is use the add(pathticks()); method, although I suppose if I can't figure it out I can try doing it by hand.  Thanks in advance! Any help would be greatly appreciated.


Unable to select whole mesh in edit mode

Hi All,  There is probably a very simple answer to this. However when I enter edit mode I am unable to select my who mesh, only the ring of faces as shown below.   What am I doing wrong.  Cheers Aaron.


Ironically, someone offered this correction:   Irregardless is a word commonly used in place of regardless or irrespective, which has caused controversy since the early twentieth century, though the word appeared in print as early as 1795. Most dictionaries list it as nonstandard or incorrect usage, and recommend that "regardless" should be used instead  Further down in the same thread, they asked, "Why do fools like you keep forgetting...", to which I replied, "Why do fools such as you keep insisting..."  So, who got it right?   Am I over-extending the lesson of my mother's pet peeve, i.e. she always corrected the TV in the '50-60s whenever she heard "Winston tastes good like a cigarette should" which properly said would have been "Winston tastes good, as a cigarette should".   Of course, today that's not seen on TV, having been replaced by "Smoking [Winston] causes lung cancer, as smoking any cigarette would".


Is it appropriate to use a table for styling a form and aligning two columns left and right

my question may sounds kind of stupid but I thought a lot about it. I've learned not to put forms into tables for several reasons like:  - responsive design issues  - even Bootstrap suggests to use divs  - use tables for real "table-things"  - don't design with tables  In my case I want to use a table because I want to make the form better to read and to use. I want to put labels in a left column and the input fields in a right column and align the left column right and the right column left so the labels are in the same line and close to each other. I explicit don't want to have them underneath the other because its harder to read. **With my solution the table-columns would automatically take the space they need. With twitter bootstrap for example I need to use classes like "col-xs-6" to say how width a column should be. Further sometimes all labels are kind of short so I don't need as much columns, sometimes some of them are very long so I need a lot more columns. But in my case I don't want do define this. It should happen automatically.  So my question is: Is it okay to use tables in forms in order to be okay with web standards and the state of the art? For me aligning  (left column right, right column left) is very important and not to use JavaScript. And if no is there an alternative?  [EDIT] I've put a graphic in here which explains my problem pretty foot. I have to say: I'm looking for a solution without javascript


Prove that if $U$ is a linear operator on $V$, then $UT=TU$ if and only if $U=g(T)$ for some $g(T)$.

Let $T$ be a linear operator on a vector space $V$, and suppose that $V$ is a $T-$cycle subspace of itself. Prove that if $U$ is a linear operator on $V$, then $UT=TU$ if and only if $U=g(T)$ for some polynomial $g(t)$. $\textbf{My attempt:}$ Suppose that $U: V \to V$ is a linear operator, $U=g(T)$ for some $g(T)$ and $V$ is generated by $v$, then the set $$\beta=\{v,T(v),T^{2}(v),...T^{k}(v)\}$$ where $\dim(V)=k$ is a basis for $V$, we need to prove that $UT=TU$, but $T(T^{k})=(T^{k})T=T^{k+1}$ and $T$ is linear, so $UT=TU$. $\textbf{My final attempt:}$ We need to prove that if $U$ is a linear operator on $V$, then $UT=TU$ if and only if $U=g(T)$ for some polynomial $g(t)$. $(\Longleftarrow)$ If $U=g(T)$ for some polynomial $g(t)$, so $$UT=\left(\sum_{k=0}^{n}a_{k}T^{k}\right)T=T\left(\sum_{k=0}^{n}a_{k}T^{k}\right)=TU$$since $$T(T^k)=(T^k)T=T^{k+1}$$ and $T$ is a linear transformation, so $TU=UT$. $(\implies)$ Suppose $V$ is generated by $v \in V$, then the set $$\beta=\{v,T(v),...,T^{k-1}\}$$ is a basis. So the vector $U(v)$ could be written as  linear combination of basis $\beta$. So $U(v)=g(T)(v)$ for some polynomial $g(t)$. If $UT=TU$, we want to prove that $U=g(T)(v)$ for that we can prove $\forall \hat{v} \in \beta: U(\hat{v})=g(T)(\hat{v})$. Indeed $$U(T^{n}(v))=T^{n}(U(v))=T^{n}g(T)(v)=g(T)(T^{n}(v)), \quad \forall n \in \mathbb{N}$$ Finally, I proved that if $U$ is a linear operator on $V$, then $UT=TU$ if and only if $U=g(T)$ for some polynomial $g(t)$.$\Box$


If I try to shutdown my computer it simply takes me back to the login-screen. I looked around and found :  Type in terminal:   sudo gedit /etc/default/grub Find the line: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" Change this to:GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi=force" Save the file and close the file.  Finally, in terminal: sudo update-grub   But now there is a new problem when I try step 5 it says:  *myname*@ubuntu:~$ sudo update-grub [sudo] password for *myname*:  /usr/sbin/grub-probe: error: cannot find a device for / (is /dev mounted?). *myname*@ubuntu:~$    I am new whit linux and dont know what to do.


When I start see this massege I want start normal with out this black screen

emphasized text UBUNTU: clean, 250477/60669952 files, 17953521/242661888 blocks


Provide free tag icons for non-profit projects

It is possible to add icons to tags as part of promotions. However, several tags exist that would benefit of an icon but without any likely sponsor (E.g. open standards, some programming languages, and several open-source projects)  Stack Exchange sites would look more interesting if such tags had icons, and possibly that would also make potential sponsors more interested in sponsoring tag icons.


Prove that $f_n$ is integrable in $[0,1]$.

Prove that for every $n\in\mathbb N$, the function $f_n$ define by $$f_n(x)=\begin{cases} 1, & \text{ if } x=p/q\in\mathbb Q;\ \gcd(p,q)=1;\ q\leq n; \\  0 & \text{ other case }   \end{cases}.$$ is Riemann integrable in $[0,1]$. What I have in mind is that this function is quite similar to the Dirichlet function, which is not integrable in the $ [0,1] $ interval, and I have already tried this before. But I don't know how true what I'm saying is.


file transfer speed over wifi homesharing too slow

Recently I wanted to transfer some movie files (ranging from 1gb to 4.5gb) from one computer on the ground floor to another on the first floor.   The wifi router Im using is this one most likely:    The speed at which I am able to transfer averages around 1Mb/s.  How can I make it faster.  Both the laptops that I am using for transfer are relatively new so the wifi adapters in them cant be too slow. None of the hard drives in the laptops are SSD but I still would like to know how I can increase the transfer speed.  Also the wifi signals on the laptop arent too bad.  Thanks.


Is there a places menu in Unity, similar to the one in the old gnome interface? I really liked having such quick access to remote shares.


How to take a full page screenshot in Mac OS Safari?

I'm looking for a  that can take full page screenshots. I am aware there are various extensions, but haven't found any that would take full page images.


Can mini-batch gradient descent outperform batch gradient descent?

As I was reading and going through the second course of Andrew Ng's deep learning course, I came across a sentence that said,  With a well-turned mini-batch size, usually it outperforms either gradient descent or stochastic gradient descent (particularly when the training set is large).  But how is it possible? can mini-batch gradient descend really give us a better set of weights and biases even though it's not updating them based on the whole dataset? I can only think that it's maybe not overfitting and in that way, it can give better results.


Given a file, "test.log" with the following contents:  line1 Patient 123 45566 line2 Patient 432 line3 Patient 234 456 line4 Patient 321 line5   I am trying to select line 2 and line 4 with this pattern:  grep "Patient\s\d+\s" test.log # but this works testing at https://rubular.com/   Doesn't work nor does this:  grep "Patient\s\d+\n" test.log # but this works testing at https://regexr.com/47qd5   What am I doing wrong?


How to change file limit on SharePoint Online?

I would like to know how I can change file limits in a document library.


Finding counterexamples: bijective continuous functions that are not homeomorphisms

Let $f: X \to Y$ be a bijective continuous function.  If $X$ is compact, and $Y$ is Hausdorff, then $f:X \to Y$ is a homeomorphism.   My goal is to demonstrate the necessity of both the compact and Hausdorff property of $X$ and $Y$ respectively.  I want to know if my counter examples are correct:  Let $f: X \to Y$ be the identity function.    (1)  Let $X=[0,1]$ with the standard topology and let $Y=[0,1]$ with the indiscrete topology.  Then $f: X \to Y$ is continuous and bijective but not a homeomorphism.  Since $U=(1/3,1/2)$ is open in $X$, but $(f^{-1})^{-1}(U)=f(U)$ is not open in $Y$.  (2) Let $X=Y=\mathbb{R}$.  Let $Y$ have the standard topology and $X$ have the discrete topology.  Let $U=\{x\}$ since open sets are singletons.  $f(^{-1})^{-1}(x)=f(x)$ is closed in $Y$ since $Y$ has the standard topology.  Hence $f$ is not a homeomorphism.  This is the old question My goal is to demonstrate the necessity of both the compact and Hausdorff property of $X$ and $Y$ respectively.  I want to know if my counter examples are correct:  Let $f$ be the identity function.  Then $f: X \to Y$ be a bijective continuous function.  If $X=[0,1]$ with the standard topology and $Y=[0,1]$ with the indiscrete topology we have that $f:X \to Y$ is not a homeomorphism.  Let $f: X \to Y$ be a bijective continuous function, $X=(0,1)$, and $Y=[0,1]$ both with the standard topology.  It's not a homeomorphism because $f^{-1}([0,1])$ is not connected, but $[0,1]$ is connected.  The first shows why Hausdoff is necessary for $Y$ and the second shows compactness is necessary for $X$.  Are both of the examples correct?  I have no confidence in my first example because I'm having problems showing $f^{-1}$ is not continuous.  However, I am confident in my second example.


Copy and paste is not working in my VirtualBox

Recently, I want to transfer some files and folders from my Windows computer to the VirtualBox. However, I just find that the function of copy and paste is not working, but I am sure that I have enabled this function on my computer. I don't know why. This problem has caused a lot of troubles for me. It is very inconvenient for me to work between my Windows computer and the VirtualBox. What can I do to solve this question?


How value getting trimmed automatically in data table if the value contains consecutive space?

Storing a product name value in DB,For example Product Name:AFTOVAXPUR DOE  Injektionsvätska, emulsion För Får, Nöt ,Svin   The above product-name contains double space,I am searching for same product-name and displaying the search results in a JSF data-table , product-name value along with some other columns.  Issue: When rendering the product-name in data-table,JSF data-table is not displaying the exact product-name.  Actual Result:AFTOVAXPUR DOE Injektionsvätska, emulsion För Får, Nöt ,Svin   Note:- Product-Name is displaying by removing/trimming any consecutive space into one space.  Expected Result:AFTOVAXPUR DOE  Injektionsvätska, emulsion För Får, Nöt ,Svin  Note:-It should display as it is stored in DB.  Question:Is that default behavior of JSF data-table to trim space if the value contains any consecutive sapce?  Here is DataTable Code to display Product Name:  <a:dataTable id="productDatatable" var="product" cellpadding="0" value="#{LookupMBean.productBySubstanceList}" style="width:100%;float:left"                             frame="box" rules="none" border="0"  columnClasses="wid0pc,wid0pc,,,,,,,,,,,,,,,,,,,,"                             rendered="#{!empty LookupMBean.productBySubstanceList}"> <a:column>     <f:facet name="header">         <a:sortCommandLink beanName="LookupMBean" property="PRODUCT_NAME" value="#{bundle.admin_productName_label_product}" />     </f:facet>     <a:outputText id="pid" value="#{product.productName}" styleClass="wrapText"/> </a:column>       <a:dataTable>


Is kernel 4.10 hwe going to be patched for Meltdown and Spectre?

I am referring to CVE-2017-5753, CVE-2017-5715 and CVE-2017-5754 in relation to Ubuntu 16.04.3 which, if I am not wrong, has now the kernel 4.10 hwe for 64bit platforms.  I've seen the post on Dustin Kirkland blog but, in relation to 16.04, it only mentions kernel 4.4 and 4.4 hwe. Does anyone knows if the kernel 4.10  is going to be patched too?  I've also found this page of canonical people related to Meltdown (CVE-2017-5754):    but I am not able to understand it. Can someone explain me what package relates to my installed distribution and the meaning of "needs-triage", "DNE", "Pending" and so on?  Info about my platform:  uname -r 4.10.0-42-generic  lsb_release -a Distributor ID: Ubuntu Description:    Ubuntu 16.04.3 LTS Release:    16.04 Codename:   xenial  Thanks.


REQUEST: Migrate LaTeX questions to tex.stackexchange

I found some LaTeX questions on  and . There is  completely dedicated to TeX and LaTeX.  I would like to migrate the questions, but I don't have the reputation points to do this:     Flag → Closing → Off-Topic → Migration   These are the questions:


Can I perform a DNS lookup (hostname to IP address) using client-side Javascript?

I would like to use client-side Javascript to perform a DNS lookup (hostname to IP address) as seen from the client's computer. Is that possible?


How to Convert Special character in URL format

My Api does not accept special character it thoroughgoing error as access-controller allow origin does not accept My File Name is Hello{#$^%.net}.pdf  My Url Format Like This    http://localhost:5300/api/Insert/DeleteRec/1-1920-9/36/Hello%7B#$^%.net}/pdf    My Angular Code  fac.DeleteRecFromTemp = function (EnqId, UId, FileName,exten) {         var fixedstring = decodeURIComponent(escape(FileName));         return $http({             url: hostapiUrl + 'Inser/DeleteRec/'+EnqId+"/"+UId+"/" +fixedstring+"/"+exten,             method: "DELETE",             headers: { 'content-type': 'application/json' }         })     }   Please Help me how can i convert that url into my browser url


Getting barcode - Exception in thread "main" java.lang.StackOverflowError

public static void main(String[] args) {      CashRegister myCashRegister = new CashRegister();      Item item = myCashRegister.getItem(123456);    public class CashRegister {     public Item getItem(int barcode) {         return this.getItem(barcode);     }    public class Item {      public int getBarcode(){         return barcode;     }   I am creating an item object in main and trying to get the item's barcode through a Cash Register class. I end up getting "Exception in thread "main" java.lang.StackOverflowError".  I do have a getBarcode method in the item class, but kept getting errors because barcode is an int, and so I cannot return an int for the Item getItem method.  Please put me in the right direction towards getting the item's barcode. Thank you.


Have Kylo Ren's Force abilities been shown before?

I'm only familiar with the movies, so in The Force Awakens I saw some use of the Force that was new to me.  Most notable were these two abilities:      freezing blaster bolts in mid-air, and directly reading someone's mind like he tried with Rey.   Have either of these happened before?


I am a permanent Resident of Canada and I am trying to understand the requirements of getting Schengen tourist visa.  I have not decided my exact dates of travel. I want to visit 6 to 7 countries. My appointment is with German Consulate for Schengen visa. All I know is I want to travel during the month of September or October for 2 weeks, depending on the best deal I get from travel agencies. How can I give them my itinerary or flight ticket details and accommodation details when I have still not decided on my exact dates?  I am also worried that, if I give hypothetical dates, they would issue a visa for just those 15 days and, later, if I cannot find any good deal for that period, it will be a waste.


Proving the geometric sum formula by induction

$$\sum_{k=0}^nq^k = \frac{1-q^{n+1}}{1-q}$$  I want to prove this by induction. Here's what I have.  $$\frac{1-q^{n+1}}{1-q} + q^{n+1} = \frac{1-q^{n+1}+q^{n+1}(1-q)}{1-q}$$  I wanted to factor a $q^{n+1}$ out of the second expression but that 1- is screwing it up...


I can't determine the maximum natural number which is unable to be represented as $17\times x+23\times y$

The given problem is the following one.  Find the maximum natural number which is unable to be represented as $17\times x +23\times y \quad x,y\in \mathbb{N}$ .  I've been solving it till following formulas with looking the solution of the problem.  $1\leqq i \leqq 22 \quad 17 \times i \equiv r_i(mod 23)$  $17\times i\not\equiv0(mod23)$  $n(r)=22$  Therefore  we can assume the problem's formula as $(1\leqq x\leqq23 \land y,q\in\mathbb{N})\quad 17\times x+23\times y =23\times q+r\prime \quad\dots(1)$ .  $\uparrow $Because if x is greater than 23,then $17\times x$ is represented as $17\times(23\times t+u)\quad (t\in \mathbb{N,u \in\{1,2,...,23\}})$  $=17\times (23\times t)+17\times u ...(2)$  and $1$st term of $(2)$ is able to be absorbed in $2$nd term of$(1)$.  And my problem begins from here.  The solution says that it is possible to be represented the all natural numbers which are greater than $17\times 23$ with $(1)$and it is impossible to be represented $17\times23$,so the answer is $17\times 23$.  Of course I can deduce that $17\times 23 $ is unable to be represented as a form of $(1)$ but I can't understand that"it is possible to be represented the all natural numbers which are greater than $17\times 23$".  How could this proven?.


What is the use of __name__ == "__main__" in python?

I tried using __name__ == "__main__" in my python program, but didn't understand it properly. Below is my code block:  def main():   print 'hello' if __name__ == '__main__':   main()


Is a GUID unique 100% in the same machine?

I want to use GUID as my ID System,  And I want to be sure that I will always get unique ID.  Should I add a test for uniqueness?


From Harvard's CS50 course  basically he has a function  where he says  do {     int n = get_int("Positive number") } while ;   He wants the program to repeat positive number until the user inputs a positive number. Why is the while loop on the bottom of his do function?


List of Table, Koma-script: how to not have the entire caption?

I use the KOMA-script to write the thesis and when i call the \listoftables I would like to modify some entries. For example, for the following table:  \begin{table} \centering \begin{tabular}{c|cc|cc|cc|cc}      &\multicolumn{2}{c}{Model 1} & \multicolumn{2}{c}{Model 2} & \multicolumn{2}{c}{Model 3} & \multicolumn{2}{c}{Model 4}       \tabularnewline    \hline  \hline   $ A $ & & & &  &  & & &  \tabularnewline              $ B $ & & & &  &  & & &\ \tabularnewline \hline \end{tabular} \caption{{\sc Size}: Rejection frequencies of asymptotic and bootstrap test.  The sample $T$ is 1000.  Note that we use the principal component analysis for A.} \label{tab:size} \end{table}     I would like only this sentence in the list of table: {\sc Size}: Rejection frequencies of asymptotic and bootstrap test. If you need more information about my .tex, let me know.


From Kolkata to Guangzhou, China. Transit ticket to Bangkok suvarnabhumi airport

Hello I am Bangladesh Citizen currently studying in india and I am on a tourist  visa. In the month of October 2019 I am travelling to china for vacations and I booked a ticket from india to Bangkok and than form Bangkok to china with a layover time of 10 hours in Bangkok and I am not going to leave the airport but my flights are different, so do I need to get and Airport Transit Visa in Bangkok?


What does the degree of a polynomial have to do with the finite extension of a body?

Let L : K be a finite extension, and let p be an irreducible polynomial over K. Show that if op and [L : K] are coprime, .then p has no zeros in L .


Prove that for any natural number $n>1$, we have $(2n)!<(n(n+1))^n$    I tried using induction, but I failed in that approach, I rather found it was untrue, but on several case testing, I found it to be true. I am out of ideas here, please help. Thank you.


Cylinder. OXYZ. 3D Cylinder . cylinder with dots

i whant help with drowing cylinder in 3d  with dots(p1,p2,...pn) on both side cylinder


In which countries are Australian citizens legally allowed to work while visiting as a tourist besides New Zealand and Georgia?

I know as an Aussie  as I did so in 2011/12.  I also know  as Australians are granted a special status there.  But are there any other countries where this is possible, as a tourist?  I don't intend to be an expat, actually moving to any country where special work visas, residency, or anything more complicated along those lines is required. I'm only interested in countries where I can arrive as a tourist yet I'm still permitted legally to work there.


Create a terminal command to open another user profile in chrome

How can I create a terminal command to open another user's profile in Chrome? It takes me a long time to switch between them because I have a lot of users in Chrome.


how to switch to backup battery when power fail?

I have a project running with MCU supplied with a 24V power supply regulated via an SMPS to 9V also, I have Li-ion battery pack 9V  how to connector these two sources to run the MCU with battery pack when the power failure occurs?  or   what is the best way to switch from battery to power supply and power supply to battery?


What is the differentiating factor between work and heat?'

Although work and heat do the same thing (increase or decrease the internal energy of the system), There is still a fundamental difference between them. For example, The way in which entropy is defined is a very good way to differentiate between work and heat. But, why is there such a distinction between the two things? Is it the limitation of Newtonian mechanics that it never accounted for something like heat which could also change the energy of the system? Is the word "Thermodynamical work" or "Hidden work" suitable for heat?


How Many Diphthongs Are There In English?

I was talking to a person who said that there were only two. I think she said that the "ou" in house is one of the two.  I told her that the way the letter "i" is pronounced is a diphthong, and she said it wasn't. She said it was just one vowel, "i" and that that was that.  She said she studied phonics and was writing her thesis (on child development, I think) on this kind of stuff. She said her book said there were only two diphthongs and that I was wrong.  So, how many are there? I told her I think there are probably more like ten. I thought of six immediately, but she said they weren't diphthongs because her book didn't say they were.   "i" in time "i" in bite "o" in bone "a" in bane "oi" in boink "ou" in house


I'd like to take a simple cross section in Blender 2.7 using the Cycles renderer. I would think this would be easy, and there is even a , but that tutorial is for Blender 2.4, and does not work with 2.7. Can someone post a simple tutorial about how to create a cross section in the latest version of blender. Here is that I have come up with so far, but the edge is not sharp and I cannot figure out how to adjust it:


Alignment issue in 'Your Sites' section in the Android app

There is some unwanted extra spaces in between each site in the Your Sites section.  Steps to reproduce:   Touch the Nav Icon in the left top corner Touch the EDIT link in YOUR SITES Scroll the screen; there is unwanted spaces in between the each site   For reference I recorded the same:    Configurations:   App Version: 1.0.85 Device Manufacturer: Motorola Device Model: XT1033 OS Version: 5.1 (2)


If Noise is an interface and Animal is a class that implements it, what is the meaning of Noise n = new Animal()?

For example Noise is an interface and Animal is a class that implements Noise. Why can I write under main:  Noise n = new Animal();   And what is the meaning of it?


Let $T:V\rightarrow W$ a linear transformation, $i_w:W\rightarrow W^{**}$ and $i_v:V\rightarrow V^{**}$ canonical morphism of biduality.  Prove $i_w\circ T=T^{**}\circ i_v$  I' m very very confused with this exercise.  Suppose i need to prove this:  $i_w\circ T\subset T^{**}\circ i_v$ and $T^{**}\circ i_v\subset i_w\circ T $ but  i don't have idea of how to prove this. Can somone give me a hint?


A question on PWM frequency of a DC motor

I'm planning to pwm-control four of the following motors by a single ArduinoUno:   For some reason the nearest pwm frequency I can set is 31kHz.   The other options are: 244, 488, 976, 3096, 7812 and 62500 Hz  In the data-sheet of this motor:  it is written "※PWM Frequency：25kHz"  Would that be an issue if I use 31kHz or one of the other frequancies? Which one would work or none?


jquery dont work when button its calling from ajax

Page1.php       (I have the same function button for alots  but diferent ID)  when they its load from page with ajax dont works  Page2.php   <input type="button" id="reload">

     Only work at first time but when push reload the script (alert) dont work again, i can see the page its loaded fine but script no.


Escaping regex string and use it with RandExp

I attempt generating text based on regular expressions using the . I escape the regular expression (which is a string) and use it with RandExp, but the end result is not as expected. What am I doing wrong? I want the end result to be something like: 123-12-1234 or 415-63-8345 import randexp from "randexp";  function main() {        const input = "^\d{3}-\d{2}-\d{4}$";     const escaped = escapeRegExp(input);     const regExp = new RegExp(escaped);      console.log(new randexp(regExp).gen()); // Output: ^d{3}-d{2}-d{4}$ <-- }  function escapeRegExp(string) {     return string.replace(/[.*+?^${}()|[\]\\]/g, '\\$&'); // $& means the whole matched string }  main();  The escapeRegExp(string) function is fetched from these URLs:     Thanks!


I want to use salesforce rest api with Silverlight application. But I am getting security error.  Is there any way to allow and configure ClientAccessPolicy for salesforce rest api service.


Let $\{f_n(x)\}$ be a sequence of polynomials defined as $f_1(x) = (x - 2)^2$, $f_{n+1}(x) = (f_n(x) - 2)^2$; $n \ge 1$.

Let $\{f_n(x)\}$ be a sequence of polynomials defined as  $$f_1(x) = (x - 2)^2$$  $f_{n+1}(x) = (f_n(x) - 2)^2$;   $n \ge 1$. How to find the constant term and the coefficient of $x$ in $f_n(x)$.


I'm trying to obfuscate my Bash script, so that it's still executable but if you try to read it you won't understand it. And my question is, how can you achieve this?


Finding the fallacy in this broken proof

Today, a friend gave me a "proof" of $1=2$ and challenged me to find the fallacy.     $1 = 1$      $1 = 1 + 0 + 0 + 0 ...$      $1 = 1 + 1 - 1 + 1 - 1 + 1 - 1 ...$      $1 = 2 - 1 + 1 - 1 + 1 - 1 ...$      $1 = 2 + 0 + 0 ...$      $1 = 2$   My answer was that once you turn the initial $1 + 1$ into a 2, everything is offset so a $-1$ is always left at the end no matter how many times it is repeated. This negative one balances out the $2$ at the beginning so $1=1$ still holds true. I.e.  $$1 = 1 + 0 + 0 + 0 ... = 1 + (1 - 1) + (1 - 1) + (1 - 1) = 2 + (-1 + 1) + (-1 + 1) - 1$$  However, my friend claimed that my answer only applies if the $+ 1 - 1$ repeats for a finite number of times. He argues that because the sequence repeats infinitely and things work differently when working with infinity, my answer is not valid.  Can anyone enlighten me to the true fallacy in this proof?


Why am I starting to see Stacks forum style on other websites?

Is it possible to find out if a certain website running a similar forum style to Stack is actually a clone or a new work?  Not trying to give any credit to this site but if you visit  forum(dot)techtudo(dot)com(dot)br/ you will see the same style.  I've read all the clones threads on Stack and know about the list of possible clones but I checked out those websites in that list but none are similar to these others. IS there a way that Stack can detect their code on other platforms?  Example:   Any ideas?


What is the Necessity of $...$ Around Numbers?

I typed up an assignment with a lot of numbers in LaTeX and turned it in to my adviser.  When he returned it to me with some corrections, one of which was a lot of $ around my numbers.  I understand that $ are necessary around some mathematical formulas, but I was just using numbers like -2 and 4.  I did not see any change in the font of the numbers when I added the $ either.  Since my adviser did not want to give me an explanation, what is the rationale?


Any elegant way to operate with generic types?

I am working in a small educational project where we have to implement a n-dimensional matrix. Depending on the context, this matrix has either to work with our own built-in ComplexNumber struct or with System.Double and for very simple examples, with integral types (mainly System.Int32).  Due to the nature of the application, we are not demanded to implement lightning fast performance.   My first idea was therefore to implement a Matrix<T> where T would somehow need to be restricted to "numbers".  The obvious problem in doing this is that there is no way right now in the language to constraint the generic type T with defined operators. Also I do not see an easy way to restrcit T to reasonable types.  My questions are:    Can somebody please point me in the direction of an elegant way to make mathematical operations with generic types that doesn't compromise performance too much and to somehow make that work with built in types (if possible). If Eric ever reads this, does this feature (constraining generic types by defined operators) ever come up in hypothetical future versions of C# design meetings and has it ever been close to making it into the language?   I know its easier and better to implement a ComplexMatrix type and create wrappers around it for each matrix "sub-type" (double, integral, etc.) and pay the performance costs of the conversions between our complex type and whichever type the matrix elements happen to be. This question is more out of curiousity on how would someone implement a similar scenario.


"Thermal expansion arises from the asymmetrical nature of potential   energy curve for atoms in a solid. If oscillators were truly harmonic   separation would not change regardless of the amplitude of vibration."   I don't understand how a temperature increase might not affect the volume of a solid substance if the oscillations were harmonic?


I'm working with tcolorbox, I saw the pdf  and I want to reproduce the little green box in this image:     Can anyone help me please?


How to add Collider to a Line Renderer in unity?

I have created a semicircle using a line renderer, I need to add a collider to this so whenever enemy objects hit this they get destroyed, how do I do this. Current Code  using System.Collections; using System.Collections.Generic; using UnityEngine;  public class CreateCircle : MonoBehaviour {     // Start is called before the first frame update      public float radius;     void Start()      {         int segments =60;         int pointCount = segments+1;          Vector3[] points = new Vector3[pointCount];          LineRenderer line = gameObject.GetComponent<LineRenderer>();         line.positionCount = pointCount; //line.SetVertexCount(pointCount);          for(int i=0;i<pointCount;i++)         {             float Deg = (i*60 / segments);             float Rad = Mathf.Deg2Rad *Deg;              points[i] = new Vector3 ( Mathf.Sin(Rad) * radius,Mathf.Cos(Rad)*radius,0);             // Debug.Log(" Point: "+i+" Deg: "+Deg+" Rad: "+Rad+" Vector 3:"+points[i]);         }         line.SetPositions(points);          Mesh lineMesh = new Mesh();         line.BakeMesh(lineMesh,Camera.main,true);          MeshCollider lineCollider = line.gameObject.AddComponent<MeshCollider>();      }      void OnColliderEnter(Collider col){         Destroy(col.gameObject);     }  } ```


Are the events from Frank Herbert's "Destination Void" and "Dune" meant to be in the same universe

It's a bit of a stretch, I know, but there are a few clues.    First, the point of "Destination Void" is to create AI, which turns out to be       somewhat godlike   AI has been outlawed in the "Dune" universe after the Butlerian Jihad, probably for this very reason.  Second, one of the characters in "Destination Void" has an experience of enhanced consciousness in which her mind acts like a supercomputer, a clear parallel with the Mentats from Dune.  Third, there are several references to the "axlotl" tanks in which clones are grown, a term which is also used in various places in the "Dune" series in reference to the Bene Tleilax who also grow clones.  It's possibly that Herbert just likes reusing these concepts, but it seemed strongly suggestive that he meant these to be on the same timeline, albeit Dune happens many thousands of years later.  (Side note: I've never read -- nor do I intend to read -- the "Dune"-related books written by Herbert's son, and don't consider them canon)


How can I safely downgrade from 18.04 to 16.04

A couple of days ago I upgraded my netbook from 16.04 to 18.04.  Is there a safe way to return to 16.04? My system is the following: Memory: 3.8GB Processor: Intel® Celeron(R) CPU N3060 @ 1.60GHz × 2 OS Type: 64 bit Disk: 26.5GB


Equation with Vieta Jumping: $(x+y+z)^2=nxyz$.

Find all $n\in\mathbb{N}$ so that there exist $x,y,z\in \mathbb{N}$ that solve:   $$(x+y+z)^2=nxyz$$   I tried to attack it finding solutions, but all the solutions doesn't seem to have something in common. For example:  $$ (x,y,z,n)=(1,1,1,9)$$ $$ (x,y,z,n)=(1,2,3,6)$$ $$ (x,y,z,n)=(1,4,5,5)$$ $$ (x,y,z,n)=(2,2,4,4)$$ $$ (x,y,z,n)=(8,8,16,1)$$  I was trying to solve this problem, but someone told me that a hint to solve it is using Vieta Jumping. I don't know how to use Vieta Jumping, so can anyone help me to understand how to apply Vieta Jumping and solve the problem?


Let $A$ be a Hermitian square complex matrix of size $n$ then $\langle Ax,x\rangle=0$ for all $x \in \Bbb C^n$. Then $A=0$   I need a hint to prove it, if possible  Thank you


Is there anything I can do so that the PNG file name can have space and "ç"?  \documentclass[11pt,fleqn]{book}  \usepackage[top=3cm,bottom=3cm,left=3cm,right=3cm,headsep=10pt,a4paper]{geometry} \usepackage[portuguese]{babel} \usepackage{graphicx} \usepackage[]{titlesec} \usepackage[many]{tcolorbox} \usepackage{booktabs} \usepackage[utf8]{inputenc} \usepackage[T1]{fontenc}  \begin{document}      \section{Aba Esboço}  %Minitable     \tcbsidebyside[title=Aba esboço,     sidebyside adapt=left,     bicolor,colback=white,colbacklower=yellow!10,     fonttitle=\bfseries,center title,drop lifted shadow,     ]{%     \includegraphics[height=4cm]{Aba esboço.png}     %     }{%     Texto aqui.     } %  \end{document}     I only get some results using: aba_esboco.png    Result:    Aba esboço.png


Before using C#, C++ was my primary programming language. And the Hungarian notation is deep in my heart.  I did some small projects in C# without reading a C# book or other guidelines on the language.  In those small c# projects I used something like   private string m_strExePath;   Until I read something from SO that said:     Do not use Hungarian notation.   So why? Am I the only person that has m_strExePath or m_iNumber in my C# code?


I have some info in my database. I subsequently echo json_encode($array); the array in which the info is contained and return it to the page displaying the content via AJAX/jQuery.   For example;   "Dave's apples are sour".  My webpage displays it as:  "Daveâ€™s apples are sour".  This is obviously a character encoding issue. we've never had issues until my hosting company was acquired by a different company.  The header of the page in which the content is displayed contains:  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />   Since then we've tried the following:   mysqli_set_charset($conn, "utf8"); <- does not solve the problem echo json_encode( $array, JSON_UNESCAPED_UNICODE ); <- does not solve the problem   A echo mb_detect_encoding(); on the specific variable that contains "Dave's apples are sour" echoes: "UTF-8".  When examining the console of the page on which the info is displayed reveals that the content arrives to the script "messed up", FireBug shows the response literally being: Daveâ€™s apples are sour.  The column in which the data is contained has the following structure:  ID, Name, Type, Collations  6, BlogPost, text, utf8_general_ci    Does anybody have some new insights? I have been searching for hours on StackOverflow without result.


Let $f$ be in $L^1(\mathbb{R}). $ Show that $$\lim_{a\to 0}\int_{\mathbb{R}}|f(x)-f(x-a)|dx=0.$$  As $f\in L^1(\mathbb{R})$, we have $\int_{\mathbb{R}}|f(x)|dx<\infty. $ Define $f_n(x):=f(x-a_n)$. For each fixed $n$, $f_n(x)\in L_1(\mathbb{R}).$ I don't know how to solve this kinda of problems. Should I apply Fatou's lemma or the dominated convergence theorem? But I'm not evey sure if $f$ is bounded. I appreciate any help for this problem. I don't undstrand the proof provided in the mentioned link. I'm very new in measure theory and I think there must be some easier solution for this question.


Does the series for $\cos(x)/x$ converges?

The sequence of $$ a_x  ={\cos (x)\over x} $$ does converge to zero. As a result, intuitively $$ \sum_{x=1}^\infty {\cos (x)\over x} $$ should also converge right? But I've been told that the series diverges. This shouldn't be true... right?


Is it normal for a fast prime to exhibit purple fringing in middle of the image?

I have just bought a Nikon 50mm f/1.8D prime lens.  I took this picture (leg of my glasses frame on a mouse, and a LED desk lamp is on top of it) : f1.8, 1/80s, ISO 200   The purple fringing is right in the middle of the picture. Does it happen very often to this lens?


Combine 4 rows based on common ID and Date

I have a query that returns 4 lines per ID. I would like to be able to merge these into one single row in a new table, based on the ID and Date. Can anyone help? I've researched and seem can't find any examples. Simplified version of how the data looks at the moment:  There's no more fields to identify if it's in or out. This is a log type database usually 4 entries a day per user id.


Prove that there are only 3 integer solutions to $2^a+3 ^b=5^c$

I have figured out that $a \pmod{2} = b\pmod{2} =c \pmod{2} $ by making a few modulo tables and using that both sides of the equation must be divisible by $5$, and I have found the three solutions, I'm just at a loss as to how to prove that those are the only three. I struggle specifically with how to move from something being divisible by $5$ to something being a power of $5$. I have also tried to use the binomial expansion by noting that $5=2+3$, but I quickly ran out of ideas what to do with it.   Any help would be appreciated!


Switch between two devices on one Thunderbolt Display

I'm using a Late 2011 Mac mini with High Sierra on a Thunderbolt Display, connected by a Thunderbolt cable to the Thunderbolt port on the back side of the display.  My wife has a Mid 2015 MacBook Pro, which she wants to use on the Thunderbolt Display when I'm at work. For the connection to the MacBook Pro I´m using the fixed power/Thunderbolt cable from the display.   I'm looking for a way to switch between the two devices when both are connected to the Thunderbolt Display.