In Robert Dixon's Mathographics, a regular pentagon is constructed with straightedge and compass only.  It is the pentagon $ABCDE$ pictured below.   I am having trouble seeing why the central angles are all $72^\circ$, though. Can anyone provide the proof?  Also, does anyone know who this construction is due to? I haven't seen it anywhere, other than in Dixon's book; is it Dixon's result?     The result appears much more impressive without all the labels (which are slightly misplaced, please excuse this); however, I provided those so that answering would be easier. Also, it makes it easy to describe the steps in the construction:  1) Draw a circle (the red one)  with center $h$.  2) Draw the perpendicular lines $\ell_1$ and $\ell_2$ through $h$. Locate the points of intersection $f$, $B$, and $g$ with the red circle.  3) Bisect the line segment $gh$. Denote the center by $a$.  4) Draw the green circle with center $a$ and radius $ah$.  5) Draw the other green circle (as in (3) and 4)).  6) Draw the line segment through $f$ and $a$.  7) Locate the points of intersection $b$ and $c$ of the line segment with the circle constructed in step 4).  8) Draw the blue arcs (both have center at $f$ and the radii are $fb$ and $fc$).  9) Locate the points of intersection $A$, $C$, $D$, and $E$.   I actually have the solution to the first question, and will post it unless a more elegant explanation is provided (which is probably likely).  However, I find this construction particularly   beautiful, and would like to know who it is attributed to (Dixon doesn't say, explicitly).


Why Ejb Interface throwing NullPointerException?

I am calling my Ejb bean from My Test class.In test class i am using static  keyword in front of here userService because i am accessing the userService from the static context(from main method.)  Note: Also If i donot uses the static keyword in front of userService then also i got same error.  public class Test {      @Inject      private static UserService userService;      public Test() {         // TODO Auto-generated constructor stub     }      public static void main(String args[]){         userService.doSomething("hello");     }  }   I setup an EJB 3 interface/implementation looking like this...  UserService (interface)  package business;  public interface UserService {      public String doSomething();  }   UserServiceBean (implementation)  @Stateless @Local public class UserServiceBean implements UserService{      public UserServiceBean() {     }      @Override     public String doSomething() {         return "Work done!";     }  }   When i am calling doSomething method of UserServiceBean  class using interface from my Test class. Its giving me error like this.  Exception in thread "main" java.lang.NullPointerException     at test.Test.main(Test.java:17)   Please explain me why this error is coming.


How do I scale the enormously sized desktop icons on Ubuntu 18.04?

I just upgraded to 18.04 (with GNOME 3.28) from 16.04. I am using gnome-shell, gnome-ubuntu-desktop. After upgrading the icon size on desktop are very large.  I am unable to find my option to decrease the size in preferences. How do I decrease it?


Is there a closed form for $\sum_{k=0}^n \frac{x^k}{k!}$?

What is the closed form of  $$\sum_{k=0}^n \frac{x^k}{k!}$$  as a function of $x$ and $n$?  Knowing that it converges to $e^x$ when $n\to \infty$.


I have Ubuntu 14.04 32-bit on an external HDD (Samsung M3 Portable, 500GB) and want to add other entries for various diagnostic software (UBCD, bitdefender antivirus...) to GRUB on the same disk.    Is it possible, and if so, how?


Car driving through walls with transform.Translate()

I need help with a script for a very simple car that uses transform.Translate:  public class car1 : MonoBehaviour {      public PauseMenu pause;     [Space]     public Car_Script car_s;     public float speed;     public GameObject car;      void FixedUpdate()     {          if (car_s.InCar == true)         {             if(pause.isPaused == false)             {                 if (Input.GetKey(KeyCode.W))                 {                     car.transform.Translate(Vector3.forward * Time.deltaTime * speed);                      if (Input.GetKey(KeyCode.A))                     {                         if (speed <= 0)                         {                         }                         else                         {                             if (speed > 0F && speed <= 50F)                             {                                 car.transform.Rotate(Vector3.down, 2F);                             }                             else if (speed > 50F && speed < 90F)                             {                                 car.transform.Rotate(Vector3.down, 1.3F);                             }                             else if (speed > 90F)                             {                                 car.transform.Rotate(Vector3.down, 0.9F);                             }                          }                     }                     if (Input.GetKey(KeyCode.D))                     {                         if (speed <= 0)                         {                         }                         else                         {                             if (speed > 0F && speed <= 50F)                             {                                 car.transform.Rotate(Vector3.up, 2F);                             }                             else if (speed > 50F && speed < 90F)                             {                                 car.transform.Rotate(Vector3.up, 1.3F);                             }                             else if (speed > 90F)                             {                                 car.transform.Rotate(Vector3.up, 0.9F);                             }                          }                     }                 }             }         }     } }   Whenever I drive the car it immediately goes through walls.   I have colliders on everything. The car has mesh colliders set to convex.   I've searched around quite a bit for answers and it seems that a common one is using rigid bodies. But whenever I even put a rigid body on the car, it flies out into the sky.


I want to build the  , but the following error appear after running the sell script ./linux_build  :      FAILED to find GTK+... CMake Error at   /usr/share/cmake-2.8/Modules/FindPackageHandleStandardArgs.cmake:108   (message):   Could NOT find Lua51 (missing: LUA_LIBRARIES   LUA_INCLUDE_DIR) Call Stack (most recent call first):   /usr/share/cmake-2.8/Modules/FindPackageHandleStandardArgs.cmake:315   (_FPHSA_FAILURE_MESSAGE)   /usr/share/cmake-2.8/Modules/FindLua51.cmake:76   (FIND_PACKAGE_HANDLE_STANDARD_ARGS)   cmake-modules/FindThirdPartyLua.cmake:9 (FIND_PACKAGE)   plugins/processing/stimulation/CMakeLists.txt:22 (INCLUDE)


What does outputting to /dev/null accomplish in bash scripts?

Oftentimes I run into small bash scripts that use this sort of syntax in if statements:  some command > /dev/null 2>&1  What is the purpose of outputting to /dev/null like that, and what does the 2>&1 mean?  It always seems to work but I'd like to know what it's doing.


Fastest way to split a string by space in C++

I have an unordered map like this:  std::unordered_map<std::string, std::string> wordsMap;   I also have string like this  std::string text = "This is really long text. Sup?";   I'm looking for the fastest solution to split the text string by space and add each word to the unordered map without using third-party libraries. I'll only split it by space, so I'm not looking for solution with changeable delimiter.  I figured out this solution:  void generateMap(std::string const& input_str, std::string const& language) {     std::string buf; // Have a buffer string     std::stringstream ss(input_str); // Insert the string into a stream      while (ss >> buf)         wordsMap.insert({ buf, language }); }   Are there any faster solutions?


Why is AUC higher for a classifier that is less accurate than for one that is more accurate?

I have two classifiers   A: naive Bayesian network B: tree (singly-connected) Bayesian network   In terms of accuracy and other measures, A performs comparatively worse than B. However, when I use the R packages ROCR and AUC to perform ROC analysis, it turns out that the AUC for A is higher than the AUC for B. Why is this happening?  The true positive (tp), false positive (fp), false negative (fn), true negative (tn), sensitivity (sen), specificity (spec), positive predictive value (ppv), negative predictive value (npv), and accuracy (acc) for A and B are as follows.  +------+---------+---------+ |      |    A    |    B    | +------+---------+---------+ | tp   | 3601    | 769     | | fp   | 0       | 0       | | fn   | 6569    | 5918    | | tn   | 15655   | 19138   | | sens | 0.35408 | 0.11500 | | spec | 1.00000 | 1.00000 | | ppv  | 1.00000 | 1.00000 | | npv  | 0.70442 | 0.76381 | | acc  | 0.74563 | 0.77084 | +------+---------+---------+   With the exception of sens and ties (spec and ppv) on the marginals (excluding tp, fn, fn, and tn), B seems to perform better than A.   When I compute the AUC for sens (y-axis) vs 1-spec (x-axis)  aucroc <- auc(roc(data$prediction,data$labels));   here is the AUC comparison.  +----------------+---------+---------+ |                |    A    |    B    | +----------------+---------+---------+ | sens vs 1-spec | 0.77540 | 0.64590 | | sens vs spec   | 0.70770 | 0.61000 | +----------------+---------+---------+   So here are my questions:    Why is the AUC for A better than B, when B "seems" to outperform A with respect to accuracy?  So, how do I really judge / compare the classification performances of A and B? I mean, do I use the AUC value? Do I use the acc value, and if so why?  Furthermore, when I apply proper scoring rules to A and B, B outperforms A in terms of log loss, quadratic loss, and spherical loss (p < 0.001). How do these weigh in on judging classification performance with respect to AUC? The ROC graph for A looks very smooth (it is a curved arc), but the ROC graph for B looks like a set of connected lines. Why is this?   As requested, here are the plots for model A.      Here are the plots for model B.      Here are the histogram plots of the distribution of the probabilities for A and B. (breaks are set to 20).      Here is the scatter plot of the probabilities of B vs A.


Why is there a performance difference between LINQ (c#) vs Seq (f#)

I made very simple C# and F# test programs.  using System; using System.Collections.Generic; using System.Diagnostics; using System.Linq;  namespace ConsoleApplication2 {     class Program     {         static int Remainder(int num)         {             return num % 2;         }         static int SumOfremainders(IEnumerable<int> list)         {             var sum = 0;             foreach (var num in list)             {                 sum += Remainder(num);             }             return sum;         }          static void Main(string[] args)         {             Stopwatch sw = new Stopwatch();             var nums = Enumerable.Range(1, 10000000);             sw.Start();             var a = SumOfremainders(nums);             sw.Stop();             Console.WriteLine("Duration " + (sw.ElapsedMilliseconds));             Console.WriteLine("Sum of remainders: {0}", a);         }     } }   let remainder x = x % 2     let sumORemainders n =     n    |> Seq.map(fun n-> remainder n)    |> Seq.sum  let seqb = Seq.init 10000000(fun n->n) let timer =System.Diagnostics.Stopwatch() timer.Start() let a =(sumORemainders seqb ) timer.Stop() printfn "Elapsed Time: " System.Console.WriteLine timer.ElapsedMilliseconds printfn "Sum of squares of 1-100: %d"  a   [<EntryPoint>] let main argv =       0 // return an integer exit code   c# 71 ms f# 1797 ms  I made second version from F# which work similar than c#  let remainder x = x % 2     let sumORemainders (input:seq<int>)  =     let mutable sum = 0     let en = input.GetEnumerator()     while (en.MoveNext()) do          sum <- sum + remainder en.Current      sum   let seqb = Seq.init 10000000(fun n->n) let timer =System.Diagnostics.Stopwatch() timer.Start() let a =(sumORemainders seqb ) timer.Stop() printfn "Elapsed Time: " System.Console.WriteLine timer.ElapsedMilliseconds printfn "Sum of squares of 1-100: %d"  a   [<EntryPoint>] let main argv =       0 // return an integer exit code   but the result not not changed significantly (1650ms)  I don't understand the big difference in speed between the two languages.  The two programs have very similar IL code, both use IEnumerable, moreover the F# replace the function call with operation.  I rewrote c# code based on f# IL code.  static int SumOfremainders(IEnumerable<int> list)         {             var sum = 0;             IEnumerator<int> e = list.GetEnumerator();             while (e.MoveNext())             {                 sum += e.Current % 2;             }             return sum;         }   The IL code of two programs are same but the speed still very different. I found the IL difference thanks for  Foggy Finder  The slow code  [CompilationMapping(SourceConstructFlags.Module)] public static class Program {     [Serializable]     internal class seqb@18 : FSharpFunc<int, int>     {         internal seqb@18()         {         }          public override int Invoke(int n)         {             return n;         }     }      [CompilationMapping(SourceConstructFlags.Value)]     public static IEnumerable<int> seqb     {         get         {             return $Program.seqb@18;         }     }   The fast code  [CompilationMapping(SourceConstructFlags.Module)] public static class Program {     [CompilationMapping(SourceConstructFlags.Value)]         public static int[] seqb         {             get             {                 return $Program.seqb@20;             }         }


What does it mean to compute eigenvectors of a covariance matrix if the data were not centered first?

Say $\mathbf{X} \in \mathbb{R}^{n \times p}$ and $\boldsymbol{\Sigma} = \frac{1}{n}\mathbf{X}'\mathbf{X}$. The eigenvector decomposition of $\boldsymbol{\Sigma}$ gives $\boldsymbol{\Sigma} = \mathbf{P}\boldsymbol{\Lambda}\mathbf{P}'$ where $\mathbf{P}$ are the eigenvectors and $\boldsymbol{\Lambda}$ is a diagonal matrix with eigenvalues on the diagonal. The singular value decomposition of $\mathbf{X}$ gives $\mathbf{X}=\mathbf{U}\mathbf{S}\mathbf{V}'$, where $\mathbf{U}$ contains the left eigenvectors of $\mathbf{X}$, $\mathbf{V}$ contains the right eigenvectors of $\mathbf{X}$, and $\mathbf{S}$ is a diagonal matrix with singular values on the diagonal. The eigenvalues of $\boldsymbol{\Sigma}$ will equal the squares of the singular values of $\mathbf{X}$ only if $\mathbf{X}$ was centered (the mean of $\mathbf{X}$ was removed). If I plot the cumulative variance explained by the principal components, the plot will (obviously) be different depending on whether $\mathbf{X}$ was centered first.  I'm trying to understand what the eigenvectors mean if I don't center $\mathbf{X}$ prior to doing the decomposition. I'm working on an naive algorithm that involves performingPCA online. I need to recompute eigenvectors after observing each new data point, and my results are much worse if I recenter the data set as I observe new data points. However, if I pretend to have seen all the data at first, center the data, and compute the eigenvectors of the entire centered data set, my (offline) performance is much better than if I had not centered my data.  Could someone please provide some intuition as to what centering the data set does and how this might be affecting my algorithm performance? Also, what is the difference in the singular values computed before and after centering the data?


I need to replace test word up to next comma in a string. For example the string is "abc test xy, tmy test 1, vks , csb"; The output after replacement should be "abc , tmy, vks,csb". Removed test followed by any character or number up to comma.  I tried the following code but did not work.  import java.sql.Timestamp; import java.time.Instant; import java.util.regex.Matcher; import java.util.regex.Pattern;   public class TESTREPLACE {      public static void main(String[] args) {         String str = "abc test   xy, tcs test  1, vks , csb ";          String regex = " default.+\\,";         Pattern pattern = Pattern.compile(regex);         Matcher matcher = pattern.matcher(str);         System.out.println(matcher.replaceAll("\\,"));     } }


Get the last statement execution date on an MSSQL Database

In an MSSQL Database, I am trying to know when was the last statement executed for that database.  So, is there any log that I can use to see the required activity records (could be the Transaction Log, but I am not sure how to get dates from it)?


Why must "either must die at the hand of the other for neither can live while the other survives"?

The full prophecy by Trelawney, the part my question is about in bold:     "The one with the power to vanquish the Dark Lord approaches ... born to those who  have thrice defied him, born as the seventh month dies ... and the Dark Lord will mark him as his equal, but he will have power the Dark Lord knows not ... and either must die at the hand of the other for neither can live while the other survives ... the one with the power to vanquish the Dark Lord will be born as the seventh month dies ..."    – Sybill Trelawney (to Dumbledore)    I am interpreting      for neither can live while the other survives   as: Harry can't live while Voldemort survives and vice versa. But why? It clearly worked until the end of book 7. One could argue with Dumbledore's thery of the self-fulfilling prophecy. But clearly Voldemort was smart enough to see that there was no mechanism that would kill him just because Harry stayed alive.    and either must die at the hand of the other    Again: Why? If somebody else destroyed all Horcruxes and then killed Harry, Voldemort would be just as vulnerable and could be killed by anyone. On the other hand, Harry could have been killed by anyone - his mum's protection transferred to Voldemort by Harry's blood was only helping against Voldemort.  I guess that I am interpreting this part of the prophecy in the wrong way or maybe there is an alternate, less obvious and more tricky one. So my question is: What exactly does the highlighted part of Trelawney's prophecy state?


"An illegal choice has been detected. Please contact the site administrator." When I try to submit the form this validation error is thrown

function user_form_edit_form_alter(&$form,&$form_state,&$form_id) {       if ($form_id=="user_register_form") {            $form['profile_user_profile']['field_user_group']['und']['#ajax'] = array(                                                                          'event' => 'change',                                                                         'wrapper' => 'edit-profile-user-profile-field-user-type-und',                                                                         'callback' => 'get_user_type',                                                                         'method' => 'replace',                                                                         'effect' => 'fade'                                                                          );            $form['#submit'][] = 'user_form_edit_form_alter_submit';    }  }    function get_user_type(&$form, &$form_state) {        $selected_user_group = $form_state['values']['profile_user_profile']['field_user_group']['und'][0]['tid'];    //  return '<pre>' . print_r($form, 1) . '</pre>';         // 14= USB , 15= Primary Contractor , 16 = Subcontractor       $output = "";      $output .= '<select class="form-select required" name="profile_user_profile[field_user_type][und]" id="edit-profile-user-profile-field-user-type-und">';      //  if USB then Director, USB Staff, USB Project Manager, Subcontractor          if ($selected_user_group == 15) {                  $output .= '<option value="8">PC Staff</option>';                 $output .= '<option value="9">PC Project Manager</option>';                 $output .= '<option value="10">SC</option>';           }          else if ($selected_user_group == 16) {                  $output .= '<option value="10">SC</option>';           }          else {             $output .= '<option value="5">Board Member</option>';             $output .= '<option value="6">USB Staff</option>';             $output .= '<option value="7">USB Project Manager</option>';           }       $output .= '</select>';      return $output;   }     //  Submit Handler Function    function  user_form_edit_form_alter_submit($form, &$form_state) {          if (isset($form_state['values']['profile_user_profile']['field_user_type']['und'][0]['value'])) {              $user_type_name = $form_state['values']['profile_user_profile']['field_user_type']['und'][0]['value'];                 $user_roles = db_query("SELECT name, rid FROM role where name='%s'",$user_type_name);                   $LastCreatedUsername = $form_state['values']['name'];                 $fetch_uid_arr = db_select('users', 'u')                     ->fields('u', array('uid'))                     ->condition('name', $LastCreatedUsername, '=')                     ->execute()                     ->fetchAssoc();                  $uid = $fetch_uid_arr['uid'];                 $rid = $user_roles['rid'];                 $nid = db_insert('users_roles')                      ->fields(array('uid' => $uid,'rid' => $rid,))                     ->execute();         }   }   ?>enter code here


Java String not working, printing different names

So I wrote up a code that will make the user enter the name "Jack" but if he enters any other name it will say "That is not your name!" but i'm having trouble to make it do that. For example when I enter that name "Jack" It will say "That is not your name!" and when I enter a name like Joey for example it will say the same thing.  import java.util.Scanner;  public class WhoAreYou {   public static void main(String[] args){      Scanner user_input = new Scanner(System.in);      String vYourName, vNotYourName;     System.out.print("Enter your name here: ");     vYourName = user_input.next();      /*     String vNotYourName;     System.out.print("Enter your name here: ");     vNotYourName = user_input.next();     */      if(vYourName == "Jack")     System.out.println("Your name is: "+vYourName);      else{       vNotYourName = " ";       System.out.println("Thats not your name!");     }   } }   Instead if using two Strings I tried to use one and that didn't work. Any ideas?


How can I avoid my query from splitting when receiving a ' character?

I am working in a form that submits data to my SQLServer database. This form contains 6 fields that will be submitted when clicked on 'Submit' using the following piece of code: $sql_thread = "INSERT INTO threads (thread_id, related_ticket, thread_content, is_internal_note, sent_by, timestamp)  VALUES ('$thread_id', '$related_ticket_id', '$content', '$is_internal_note', '$sent_by', '$timestamp')";  $stmt = sqlsrv_query($conn, $sql_thread); if( $stmt === false) {     echo $sql_thread;     die( print_r( sqlsrv_errors(), true) ); }else{     //if everything went well, redirect back with error code 004     header("Location: ../admin/create-thread.php?errcode=004");  }  The issue is that, if any of the fields contain a ' character, my query gets split into pieces. For example, if I type: you're amazing!, then my query will divided that into two parameters:  you re amazing!  Then I will have seven parameters to inset into the database and not 6 as it is expecting, therefore my query will fail. Is there any way I can modify my query to avoid this from happening? If I submit the form and any of the fields contain a ' character, then this error message is shown:  Thanks in advance, please let me know if any other details are needed to help this!


Let $(U_n)$ be a sequence such as $|u_{n+1}-u_n|<\frac{1}{n^2}$ show that (U_n) is a convergent sequence.  I m stuck with this question, I showed that $\lim\limits_{n \to \inf} u_{n+1}-u_n =0$ Can you help me ?


How to approach this problem of implicit differentiation?

I'm asked to find the derivative of $\frac{d}{dx}(\sin^{-1}x)=\frac{1}{\sqrt{1-x^2}}$ using implicit differentiation. The question is why do I need to use implicit differentiation when I have a function defined only in terms of $x$.


Alternate proofs (other than diagonalization and topological nested sets) for uncountability of the reals?

I recently started studying set theory and am having quite a bit of difficulty accepting Cantor's diagonal proof for the uncountability of the reals. I also saw a topological proof via nested sets for uncountability which still does not satisfy me completely, given that just like the diagonal it relies on a never ending process. In fact, the nested sets proof sounds very much like the diagonalization proof to me.  Do all proofs of the uncountability of the reals involve diagonalization? Are there any other proofs I can look at to understand? I couldn't find any on searching stack exchange. Thanks.


MySQL: How to retrieve data that contain apostrophe

I am having a problem retrieving a data from mysql that has an apostrophe in it. I don't have problem in saving a data that has an apostrophe since that I am using mysqli_real_escape_string when inserting the data to the database but I get an error when retrieving it. My sample code in PHP for retrieving the data is mysqli_query($con,"SELECT column1data FROM Table1 WHERE column2data LIKE '".$data."' ")or die(mysqli_error($con)); and the $data is the one that has an apostrophe in it.


Who knocks at the door?  Who does knock at the door?    I am confused here. Usually, first sentence is acceptable. But I did not read about the 2nd one. Is it correct? Is it an emphatic sentence of present indefinite tense?


In ZF, the Power Set Axiom (POW) says that given any set $A$, there exists a set $\mathcal{P}(A)$ such that $$ \forall a(a\in\mathcal{P}(A)\leftrightarrow a\subseteq A)\tag{1} $$     Questions:         On many occasions, I've seen POW stated like this: "For any set $A$ there is a set consisting of all subsets of $A$."      Would a more precise formulation be: "For any set $A$ which is known to exist there exists a set containing all subsets of $A$ which are known to exist."?   An instance of the Axiom Schema of Separation (SEP) essentially gives the existence of a subset of a given set. So, why doesn't POW imply SEP? Is it because POW doesn't give the existence of the individual subsets but only the set containing them all?   Conversely, does SEP and the remaining ZF axioms imply POW?


How come the dreams are shared correctly among different participants?

Please read the question before marking it as duplicate. This question maybe identical to the one below but they ask different concepts:    So my question is how are the dreams shared correctly among the individuals? I've watched the movie twice but the only thing connected to all the dreamers are the conduits used to inject sedatives to the subjects of the dream. It hasn't been explained how the dream sharing actually work. Is it some kind of a telepathic practice?


Testing if variables have a non-linear relationships with the dependent variable

How can I find evidence that a independent variable has a non-linear relationship with the dependent variable? Can I possibly achieve this by squaring all the independent variables and estimate a model containing both the squared variables and the original variables and then if the coefficients on the squared variables are a value close to 0, then we can assume that the variable has no non-linear relationship with the dependent variable?  Also, how can I find what the effect of using the logs of both the dependent and independent variables in the above case will do? Wouldn't the estimate the model be not valid as it contains multicollinearity? So is would it be more appropriate if I remove the linear terms and just estimate the model using the logs of the squared variables?


I earned two hats on a site, and I think it would be great if we can wear both at the same time.  Can this please be made possible?


Fix a sometimes happening prohibitory sign 🚫

Well, I know there's an answer to a similar question here: , but this is slightly different.  My system is  running on external drive. Actually on an external drive partition. After I installed Waves plugins I encountered this error for the first time. So I booted in my main system on internal drive and used repair on that partition by sudo diskutil mountdisk force /dev/disk2 because partition didn't show up. That didn't help. So I used diskutil repairvolume /dev/disk2s4 and after repairing it helped and I was able to boot normally. It happened twice and each time at firsrt getiing 🚫 and after repairing a volume I was working fine (I'm running on this system now).  I tried reinstalling macOS – did nothing. I have an old backup that's lacking some files. So I guess, if I backup now it's going to backup the whole drive including system folders errors. Any ideas how to fix this without erasing/restoring onanism?


Links fail when using apt-get to try and install update-manager

I have a leased server I've had for five years that is running Ubuntu 10.0.04LTS. I was trying to do an upgrade to something more recent (since apt-get kept erroring out) and found I don't have update-manager installed. apt-get can't find what it needs to install update-manager, so I'm stuck now. Ultimately, I just want to upgrade the system. So the question is how do I install update-manager when apt-get isn't making it happen?  Important point: I don't have any GUI here, only the command line.


I have tried finding solutions to this problem personally but haven't yet gotten a solution. I am to find a way to generate S colors that are as distinguishable as possible. Where S  Is a parameter.


undefined control sequence for \subfigure

using TeXShop in OS X Maverick, a simple subfigure script is returning "undefined control sequence". Although I can bypass it and still generate the image-included pdf by typing "s" to "ignore all" (of the warnings), I would still like to know the cause and fix for this. Thanks!  The sample script is:  \documentclass[a4paper,12pt]{article} \usepackage{graphicx}  \begin{document}  \begin{figure}[htdp]   \begin{center}     \subfigure{\includegraphics[width=0.3\textwidth]{fig1}}     \subfigure{\includegraphics[width=0.3\textwidth]{fig2}} \end{center} \end{figure}  \end{document}


Data Interoperability Tools appear not to be licensed?

I am having problems with Data Interoperability tools in ArcMap 10.2,When i try to use a quick import or a quick export in Data Interoperability Tools , i can not , i click but i dont have any result.    what is exactly the problem , for other arctoolbox work very well.    Solved: I added it from ArcGIS folder's setup. this extension was not installed.


Consider the following sentences:  I am staying in a hotel nearby. I am staying in an hotel nearby.  I know that both are correct. But I would like to know why? I do not see any proper reason for the second one as the 'h' is not silent as in French. So, what could be the reason?


Increase size of overall appearance in Ubuntu 18.04

How to increase the size of overall appearance in Ubuntu 18.04. Consider the following screenshots with low appearance as shown below


Give a combinatorial proof that $\sum_{k=1}^{n} {{k} {n \choose k}^2 ={ n} {{2n-1} \choose {n-1}}}$

$$\sum_{k=1}^{n} {{k} {n \choose k}^2 ={ n} {{2n-1} \choose {n-1}}}$$  How would I approach this problem to make a combinatorial proof?


There needs to be a way to delete content or disassociate your account from said content

I know this has probably been beaten to death, but there really needs to be a way to remove yourself from posted content. I understand deleting content has its issues, but certainly you should be able to transfer something you posted to an Anonymous account.   I'm really going to open myself up to trolls here, but not being able to delete things you posted is a major issue for the new careers feature. I'm not talking about stupid questions / answers I've posted so much as smart ass remarks / troll posts. You will probably say that one deserves to have their inflammatory comments stay attached to their name. I think that everyone has bad moments though, and there should be a way to publicly delete it. Not having delete forces people to create new accounts just to use the careers feature.  Edit: I just want to make it clear that I agree you shouldn't post anything you don't stand by. I'm saying though there should be some recourse for when you did.


won't instead of using' wouldn't' is possible?

I have asked many questions about "would" both in ELL and ELU. But I still have a question about the use of "would". I have recently asked a question which @Jay also answered. He used "wouldn't" in the following sentences: 1. Here, you wouldn't say, "May I ask you what is your name?" Though we break this rule for questions sometimes 2. Well, someone might say that in informal speech, but you wouldn't write it or use it in formal speech. 3. "May I ask you what's your name?" is awkward; a fluent speaker wouldn't say that.  I had asked  question in ELL and I have received answers for it. But there is one thing that I'm still confused about.  Do the meanings of the sentences above change if we use 'won't' instead of using 'wouldn't' ? can we use 'won't' in the place of 'wouldn't' without changing the meanings of the sentences above?


Mobile chat provides no feedback when a post is too long

On mobile chat, there's no indication if your post exceeds the maximum message size. I figure this is a bug. Could it be fixed?  Compare the two images of mobile chat below:      There's no visual difference. These were taken with my PC in mobile mode, but the results are the same on a phone. If the message is too long, the send button simply won't work. I found this out this morning and had no idea why my message wasn't sending. Bad reception? Was something broken?  The Desktop chat doesn't leave you guessing.      That second one is the exact same message I entered into mobile chat. There's a visible warning, and even the send button gets disabled!


How to count the number of pages between two labels? I tried to fined a way using  but not helpful.  \documentclass[12pt]{book} \usepackage{lipsum} \begin{document} \lipsum[1-20]\label{start} \lipsum[1-20]\label{end}  As mentioned in $\the\numexpr\pageref{end}-\pageref{start}$ pages ... \end{document}


Build an H-Bridge Motor Driver with 4 N-Channel MOSFET

I have bought 4 N-Channel MOSFETs to build an H-Bridge Motor Driver. My Motor drive and my power supply voltage is 12v. My TTL logic voltage is 5v as I want to speed up/down the motor with uC PWM. Now I have understood that I have problem with driving High Side MOSFETs as their Gate Voltage must be bigger in respect to their Source voltage. What are my options now? shall I change them to P-Channel MOSFETs?


When I create a variable and wrap the code in a while loop it never repeats. Here's a sample of code I tried it on.  String repeat = "y";     Scanner keyboard = new Scanner(System.in);     while (repeat == "y"){         String word1 = "this";         String word2 = "that";         String word3 = word1 + word2;         System.out.println(word3);         for(int x = 10; x<20; x = x+1){              word3 = word1 + word3;             System.out.println(word3);         }         repeat = keyboard.nextLine();     }   No matter what the input is in the end of the script, it just ends. Any help?


I can not shrink the boot drive i.e. C anymore, in order to reuse that space for the ubuntu partition which I have installed on dual boot.  I want to know how to shrink the F partition and merge that space into my ubuntu partition?


I have 2 flask restful API's . On my localhost, I open up a terminal and run uwsgi --ini /path-to-ini-file1. For 2nd API, I open up yet agan a new terminal and run uwsgi --ini /path-to-ini-file2. In VPS, I have only a single ssh window. How do I run those 2 on terminals in vps using ssh. Should I create a bin/bash script to achieve that? Any suggestion would be appreciated, thank you.


Why does my multivariate normal have a density greater than 1 (log-likelihood greater than 0)?


Oracle returning incorrect result due to numeric data type limitations?

When I run the following query Oracle returns 0.9999999999999999999999999999999999999999.  select 1/3 * 3 from dual;   However when I execute the following Oracle returns 1.0:  select 1/to_float(3) * 3 from dual;   Why the difference?


\chaptername is used even for appendix chapters in ToC

I have searched for something to resolve a problem that has shown up here:   I have tried the code from that thread. But I got an issue, that is, it adds the \chaptername even for appendix chapters:     Chapter 1. aaaaa   ....   Chapter Appendix A   How can I resolve it?


How to update VLC to the latest version?

As VLC 2.0 is released, how do I get it in Ubuntu (XUbuntu actually, in my case) 11.10? Any PPAs or packages to download? The official page says "Ask your favorite packager..."


I'll probably be scolded for this, but I couldn't find an appropriate answer here nor by seraching the internet (perhaps I need another way of phrasing the question). I use TeXLive 2020 on Debian Testing; I write primarily in Spanish and so I have need of the inputenc package to typeset accented characters, as in my name: Óscar. However, upon composing an introduction to LaTeX I accidentally forgot that I hadn't loaded this package and typed as if it had been loaded, and both the DVI and PDF outputs show accents! I compiled the following: \documentclass{article}  \begin{document} \title{Introducción a \LaTeX} \author{Óscar Guajardo} \date{} \maketitle  ¡Hola mundo! Esto es \LaTeX, un sistema de composición de documentos; estas páginas son parte de un DVI.   Ça va? È posto! Weierstraß. Łódź. \end{document}  I attach the output below; as you can see, it shows all the "special characters" without having loaded inputenc; I wrote the above code on a Bash terminal using nano, but the output is reproducible with TeXstudio and TeXmaker. I am not complaining nor I want a "solution" (since there's no problem, quite the contrary). I'm just so used to loading inputenc to write in Spanish that I'd really like to know if it is now unnecessary. Thanks!


Data sensitivity classification in SQL Server 2019

Is there any way in SQL Server 2019 to physically partition data by  and thereby allow different security mechanisms to be used with different sensitivities?


There are three doors. Behind the doors, there are 2 goats and 1 car. But we don't know which thing is present behind which door. Our target is to get the car by guessing. Afterwards, we select a door (let the 1st door). Keeping the selected door closed, another door (let the 2nd door) is open which has a goat.Now, is it beneficial to change the selection so that we can get a car?  I have known about an answer where it is said that it is beneficial to change/switch the answer.It suggested to use probability saying that, the probability of the unselected door (3rd door) increases after opening the 2nd door.But the probability of the selected door (1st door) remains unchanged. But how does it happen?


Visa free passport with a Schengen entry stamp but no exit stamp

I am a Ghanaian by birth but have Argentine citizenship. In 2015, I first went to Ghana, then went on to France where my passport was stamped.   I spent one month in France,  2 weeks in Germany, 2 weeks in Italy, 2 weeks in Belgium. When I took the bus from Brussels to London, I didn't get an exit stamp. I returned to Argentina from England; my passport was not stamped on exit there either.  I traveled from Argentina to Ghana and on to Turkey, where I am now, and my passport has an entry stamp. I'm planning to take a bus from Turkey to other areas in Europe.   Can I enter the Schengen area without a problem, since I didn't get an exit stamp from any of the Schengen states I visited in 2015 before going to London?


On what refractive index of medium depends ?

does the refractive index of a medium depends on wavelength of light passing through it ? If yes then why ?


Proving equality with a norm of a linear functional

I got help on the previous parts of this question but I'm at a loss about where to go from here. I can prove the linear functional is bounded and that the norm is less than two but this last part I am stuck on and the hint isn't helping me. Any help would be really appreciated.


I have an issue with Server 2008 and Windows 7 client machines -- the event viewer log for Internet Explorer 10 is empty.  I've googled this for the best part of my morning with no joy.   Currently tried:    Checked IE logs are enabled in event viewer. Browsed to location of event logs and noticed the date modified is 20/3/13 Tried creating a custom log and added IEFRAME as the event source, its still blank.   See below for virtually the same issue without an answer. I'm trying to investigate an issue where IE crashes and finding it difficult without logs.


Categorical Variables - Factor Reduction - Can I use the dependent variable?

I am working on a basic fraud detection model. I have about 10 independent features and I am trying to predict if a given transaction is genuine or fraud. Most of the features are categorical and each categorical variable has hundreds of factors.   As each feature has so many factors what I am currently trying to bag factor levels into larger groups. For example assume feature 1 has about 1000 unique factors. Each factor appears multiple times in the training data. I calculated the percentage of fraud for each factor. All factors with less than 10% fraud transactions were put in group A, factors with less than 20% fraud transactions were put in group B and so on.   As I am using the dependent variable for bagging the independent variables I am not sure if my strategy is legit? Can some one help me with this? Alternatively what are other approaches for reducing the number of factors


I am looking for a way to output all page IDs from the following menu:   <?php wp_list_pages('depth=1&exclude='3,5,11')); ?>   Only top level pages needed, therefore the 'depth=1'.  Any help appreciated.


This   has the same symptoms I have.   I can login with nvidia-drivers if I    recovery console at grub make filesystem writeable resume to gui login switch to tty 4  after login screen is visible login on tty4 Switch back to gui login on tty1 login is possible   How do I debug this? There is nothing useful in the text logs.  The dupe has no valid answers.


Tag score doesn't seem to have updated for a few days

I'm getting pretty close to a silver badge in a tag that I'm very interested in so over the past couple of days I have looked at my own profile daily just to see how close I am. That is when I noticed that even when I got up votes for answers with that tag, the tag score didn't update.   I found a post on meta that said that the tag-score script runs daily at 03:00 so I figured that it would soon be updated. However I haven't yet seen an update.  This is what I see in my profile     and this is what I see when fetch all my up voted answers by tag.    The tag I've been following closely is the "core animation" tag. So I can looking at the last 6 up voted answers for that tag to get an estimate of when the script last ran. This is my reputation history for the past few days with the questions with this tag highlighted:    It seems like tag score was last updated March 8 (5 days ago)


Some sites, like StackExchange, pop up an "Are you sure you want to leave this page?" dialog when you try to leave under certain conditions, such as if you have a post you haven't finished editing. This is helpful!  Unfortunately, malicious or infected sites like to use the same functionality to say, "Hey! You haven't installed our malwareantivirus to address the 111 viruses we're definitely not lying about finding on your computer!", and the "Leave this page" and "Stay on this page" options are replaced by something like "Be safe. Install our product" and "Shoot yourself in the foot". This is unhelpful!  Javascript can do some nasty stuff. When I get one of those dialogs trying to keep me from leaving a clearly-malicious site, what should my response be? Is it safe to click "Leave this page" or whatever they replaced the text with? Could a site change the behavior of the button, or intercept my attempt to navigate away and draw its own fake dialog that does whatever an attacker wants when I click on it?


Help with shell script reading data usage in a directory

I'm confused on how to get the data usage information into the variables to determine if the file size are acceptable. How do I make the variable and direct it to the rest of the script?  Write a script (called passwd_size.sh) that does these tasks:   Find the size of the /etc/passwd file If the size is greater than 2000 bytes, display a message that the file exceeds size, otherwise, display message that the file is within the size limit.     du -c "/etc/passwd" num=0 if [ $num -gt 2000 ]; then echo "File exceeds size limit." fi if [ $num -lt 2000 && -eq 2000  ]; then echo "File is within size limit." fi   Any help is greatly appreciated!!!


In survival analysis, why do we use semi-parametric models (Cox proportional hazards) instead of fully parametric models?

I've been studying the Cox Proportional Hazards model, and  this question is glossed over in most texts.    Cox proposed fitting the coefficients of the Hazard function using a partial likelihood method, but why not just fit the coefficients of a parametric Survival function using the maximum likelihood method and a linear model?    In any cases where you have censored data, you could just find the area under the curve.  For example, if your estimate is 380 with standard deviation of 80, and a sample is censored >300, then there is an 84% probability for that sample in the likelihood calculation assuming normal error.


Find the difference between two dates (Inclusive of start and end date) in Java

I need to find the difference between two dates in Java and the difference should be inclusive of start and end date. I tried using below piece of code but it is not including start and end date.  long diffDays = Days.daysBetween(new DateTime(startDate), new DateTime(endDate)).getDays();   Is there any utility method to achieve this?


Why does my Java(Android) method modify parameters that get passed in

I've got a Java method that takes a Calendar as a parameter, calculates some date before the provided date, and returns this new Calendar. Now, if I log the values of the first Calendar, initialize a new Calendar as the value of the returned Calendar, then log them both, they're shown to be the same date. Why does the method return the value of start and also change the value of startDate in the main method? Section of code that passes a Calendar to the method Dating.getStartDate(); Calendar endDate = Calendar.getInstance();  Log.i("DATING", "End Date = " + endDate.getTime());          Calendar startDate= Dating.getStartDate(endDate);          Log.i("DATING", "Start Date = " + startDate.getTime()); Log.i("DATING", "End Date = " + endDate.getTime());  The Method: public static Calendar getStartDate(Calendar end) {          Calendar start;      Log.i("DATING", "Calculating 100 previous occurrences");     for (int count = 0; count < 100; count++){         start = getPreviousOccurrence(end);      // Calculates some day before end         end = start;                             // sets end to new value of start     }     Log.i("DATING", "getStartDate() returning start date of " + start.getTime());     return start; }  And here is the log output: I/DATING: End Date = Sat Jan 09 23:13:04 EST 2021 I/DATING: Calculating 100 previous occurrences I/DATING: getStartDate() returning start date of Sat Jan 25 23:13:04 EST 2020 I/DATING: Start Date = Sat Jan 25 23:13:04 EST 2020 I/DATING: End Date = Sat Jan 25 23:13:04 EST 2020


Why does Bohr's stationary orbits not radiate energy?

I am presently in high school trying to understand the Bohr's theory. I somewhat familiar with Maxwell's laws but very soon I'll learn about them thoroughly. So please could anyone explain with respect to the EM theory why does Bohr's stationery orbit does not radiate energy?


Upvoting a downvoted answer will do +2 upvote?

I have first downvoted an answer. Then, I decided to leave it the way it was before, meaning to undo my downvote just like it never existed, so I upvote to remove my downvote. Suprise! SO seems to consider it as two upvotes!  Let's say I have an answer with -3, then I decide to downvote it making it -4. After deeper thoughts, I prefer to remove my downvote to let it the way it was before I downvoted, meaning -3, but SO makes it -2 automatically!     Wouldn't it be supposed -3, and not -2? If someone else would have upvoted, it would have made it an upvote +1, not a +2!   Am I missing something here?  In fact, is there a way to tell SO that I only wish to undo my downvote, and not upvote the answer? I may understand why it does behave this way. I only wish to undo my downvote, though.


How can the white spaces from the output of the following line:  $C++$   be omitted so that there is no white space between 'C' and '+' and the last '+'.  The current output is:  C + +   C and the pluses are considered operands and operators.


Is both parts of the hypenative word Hands-on capitalized in an ad with bullets.


Inform users of certain tags on the existence of a new SE-2.0 site and offer to automatically post the question there instead

Take for example  both at SO and SU. Now that there's , (new) users asking a LaTeX question should at least be informed that there is a new Stack Exchange site dedicated to TeX and thus increases their chance of an answer. This should happen before the question is actually posted and ideally offer the option to post the question directly there instead (without the need to copy-paste).  LaTeX is just an example, there's also , ,  etc., and it is obvious that this can only be decided on a case-by-case basis which is why I certainly do not suggest migrating questions automatically when these tags are used. But informing users of that possibility would probably help the SE network in general.


What does it mean to not be able to take the derivative of a function multiple times?

I'm taking a intro to mathematical analysis course and I'm having trouble understanding this definition.   They are talking about how it can be interesting to see what happens if you take the derivative of a function multiple times (this is discussed in the intro to Taylor polynomials). They throw this definition at us, which they call $C^kfunctions$:  A function $f: I \rightarrow \mathbb{R} $ belongs to $C^k(I)$ if it is possible to take the derivative of the function k times on $I$ and if $f^{(k)}(x)$ is continuous on $I$  I'm a little confused by this. Aren't all functions $C^\infty$ then? Can't you just keep taking the derivative of a function even if it becomes $0$? Specifically I'm on a chapter now where they are discussing curve integrals and they keep mentioning that it is a $C^2$ function. What does this mean? Can you only take the derivative 2 times?  I'm confused and can't wrap my mind around it. I would love if anyone was able to explain it in such a way that I could understand and apply it. Thanks in advance.


How can I align equations in nested align ?  \documentclass{article} \usepackage{amsmath,amssymb,amsfonts} \usepackage{flexisym}  \begin{document}  \begin{equation*}     CT_i = \left\{\begin {aligned}         &CT_{i1} = \tau \\         &CT_{i2} = H(M).e(g, g)^{s\alpha} \\         &CT_{i3} = h^s \\         &CT_{i4} = H(M)^{t.H_1(ID_{Ui})} \\         &CT_{i5} = H(M)^{t.H_1(ID_{ESP_i})} \\         &\left.\begin{aligned}             &CT_{i6} = g^{q_y(0)} \\             &CT_{i7} = H(attr(y))^{q_y(0)}         \end{aligned}\right\}\forall j \in   \mathbb{A}_{Ui}     \end{aligned}\right. \end{equation*}  \end{document}   In this case, last two lines are not aligned with rest of the lines (alignment at C, = g/h).  Please help. Thanks in advance.


$\int_{-\infty}^{\infty} \frac{\cos(αx)}{(x^2+1)(x^2+4)} \mathrm dx$ using Complex methods

$$\int_{-\infty}^{\infty} \frac{\cos(αx)}{(x^2+1)(x^2+4)} \mathrm dx. $$  I am not sure how to solve this question. Can anyone help me to approach this problem. Thanks.


I lost the Windows partition after installing Ubuntu 16.04 with Unified key

As I remember the unified key, but the problem is i search this forum and the whole youtube and evrything possibe to recover my partition .   This is exactly what happened:   I got a live Dvd to install the ubuntu, but before installation of ubuntu it asked whether you want to replace the windows 8, and i thought that it will delete the windows c folder and will replace the ubuntu latest 16  !! Then i installed the ubuntu  with warning that it will remove the windows and replace the ubuntu. And after sucessful installation of ubuntu now i faced the really painful situation that i didn't have my partition of 1 terabyte.  It has to be 2 partions on my windows. After getting this problem i searched and researched the whole internet and i got nothing but somewhere it mentioned that use testdisk but the fact is i don't have any idea with the terminal window . Since i seached officially the software database but there is so such software found. i downloaded it from the internet from their site but i don't know how to install a zip file even after extracting it. But i got the Gparted and after opening it says like this:     I have many important things on my drive so I really need to recover it!


I'm trying to understand what causes a black hole in terms of it's composition. We know a start can die and collapse into a neutron star, but if the neutro star is not dense enough to create a black hole, then what it is inside? I mean, what is more dense than a neutrons glued together?  Is a "quarks" star? are the neutrons destroyed and all the quarks inside put together?


What alternatives to MS Access exist for database management on the Ubuntu platform (LibreOffice Base isn't cutting it)

I have a web-based MySQL database, which is very important. I have used the MySQL Connector to allow me to use an MS Access database to query, and clean up my database, through an ODBC connection.   Having moved my work computer to Ubuntu Linux (finally) I was trying to avoid using a VirtualBox VM to host a Windows installation to continue using MS Access, since there are so many tools available for the Linux Platform.  Yesterday, I installed the MySQL Connector for LibreOffice from the Ubuntu Software Center, and planned to move forward with LibreOffice, just like I did with MS Access - but LibreOffice Base doesn't have any ability to do update queries (unless you are writing our SQL query by hand) - and it's still kinda clunky... IMHO.  What other database management tools exist for a Ubuntu desktop, so I can query, update, and report my web-based MySQL database, (and can completely avoid Windows and MS Access, going forward)?  Thank you in advance!


Prove $n^2 < n!$.  This is what I have gotten so far  basis step: $p(4)$ is true Inductive Hypothesis assume $p(k)$ true for $k \ge 4$  Inductive Step $p(k+1)$ : $(k+1)^2 < (k+1)!$  $$(k+1)^2 =k^2 + 2k + 1 < k! + 2k +1$$  Can someone please explain the last step this is from text, I need help understanding this, forgive me for the formatting error Im still learning


Does pure yellow exist in variations we can't discern?

If you add red light (~440 THz) and green light (~560 THz), you get what we perceive as yellow light (~520 THz). But I assume what you really get is a mixed waveform that we perceive as yellow? Suppose the red is a perfect sine wave, and so is the green, the mix of both will not be a perfect sine wave but a wobbly composite thing - right? Which is different than a perfect sine wave of ~520 THz. But we call both things "pure" yellow. Is that correct?  If so, are there animals that can discern composite pure yellow from singular pure yellow, like we can discern the mixture of multiple audio sine waves as a chord? Or is there machinery that can do that?  See also:


Hey I'm new to this site. I really like the concept, but I think that it's kinda unfun to use.  For example, what's up with having to put two spaces at the end of each line to get a line break? I've never seen a site where you have to do this before. The other formatting options are also kinda unintuitive, though with the editor, that's okay (it ain't there on the mobile version of the site, though).  Then somehow, when I was posting a comment, even with that double space method, it didn't format correctly (could be a bug). Then, when I wanted to add something to my comment, it said that you can only edit it for 5 minutes after it was posted. The hell?!  Thoughts in my head:     "This website is badly coded!" "Maybe they're making it a pain to use on purpose, so that only hard-working people will be willing to put up with it and they will get less lazy questions and answers." "Either way, there is no excuse for a modern website to not be easy and fun to use!"   Tbh, I hate writing such negative posts, but when I see something like this, I cannot hold back. Just trying to post stuff on this site got me annoyed. What were the people coding this thinking...???    Lol, why did someone add a list...? Well, have it your way. Guess one person's posts are everyone's posts over here.  This question is not identical to that other question, as I am asking about the site in general and its usability. I see, you want me to make a list...     double space for line break can only edit a comment for 5 minutes enter sends comments (is that only here in meta?) (guess it can be useful if you KNOW that it will happen, but it always causes me to send the comment by accident) no editor on mobile site (possibly something that can be added as an improvement?) website confusing for newbies (in many ways...)   In short, it doesn't really feel up to snuff to contemporary website design standards. :/ Not sure how to say it any better than that. Maybe the last point could be fixed by giving new users a comprehensive explanation about how the site works. There was some kind of "website explanation" or something, but it was rather goofy and didn't explain much.  Would be nice to get an answer from the site admins, because they can probably explain best what thoughts and ideas went into the making of their website. But I can understand if they don't have time to answer to some random user feedback. Yet they said: "Feedback is welcome", if I remember correctly.


I have a dedicated server which hosts game servers, and is vulnerable to DDoS attacks. I want to get a DDoS-protected VPS to act as a reverse proxy for UDP. The dedicated server's IP address is 7.7.7.7 and the VPS's IP address is 9.9.9.9.  The whole idea is to hide the 7.7.7.7 address, so that it's not visible to the public when connecting to my game servers. When players connect, they should be sending packets to 9.9.9.9 and receiving packets from 9.9.9.9. If 7.7.7.7 was visible, hackers could directly attack it and bypass my reverse proxy. I don't want to "route" the UDP packets. I don't care if all the players will come from the same IP address.  Is there any way I can do this on Linux? If so, what commands?


Prove that if n is even then $n^2$ is even and if n is odd then $n^2$ is odd?

How can I prove that if $n$ is even then $n^2$ is even and if $n$ is odd then $n^2$ is odd?


I'm writing a tex where I have several figures at my chapter 3, I guess it is 27 figures.  after my section 3.3 my (figure \ref{fig:.......}) are giving me the wrong figure. when it should be giving me figure 3.19 it is giving me figure 3.3 or 3.4 in every figure after section 3.3 the references are wrong.  here is part of my section 3.3, the first figure here should be the number 3.19, and the \ref is returning 3.3  \section{Arquivo Digital Log Interchange Standard File (Extensão Dlis)} \label{sec:extensaodlis}  Os arquivos no formato Dlis, podem ser importados a partir do menu  \textbf{Projeto} – \textbf{Importar} – \textbf{Arquivos Dlis}. É necessário que  o usuário defina alguns parâmetros durante a importação deste tipo de arquivo  (figura \ref{fig:importacaodoarquivodlis}). Nesta primeira etapa de importação,  você poderá associar o conteúdo importado de cada arquivo selecionado a um poço  existente no projeto, ou definir um novo nome (resultando da criação de um novo  arquivo). Na importação de apenas um arquivo, é mostrado na caixa de texto  acima da área onde o conteúdo do arquivo o caminho de acesso do arquivo  importado, mas caso tenha selecionado muitos arquivos este caminho não será  mostrado e sim apenas a relação de nomes de poços (figura  \ref{fig:importacaodoarquivodlis} , seta azul).   \begin{figure}[!h] \centering \includegraphics[scale=1]{\importacaodedados importacaodoarquivodlis.png} \label{fig:importacaodoarquivodlis} \caption{Importação de Arquivo Dlis.} \end{figure}   Na seguinte tela, serão apresentadas as informações contidas no arquivo  Dlis, Na caixa “\textbf{grupos de curvas encontrados}”, você visualizará o nome  do arquivo (poço), e se houverem arquivos “Frames” que correspondem a grupos de  curvas estes serão importados para o projeto Trace. Na tabela abaixo é possível  alterar o nome e a unidade de todas as curvas, além de associar à semântica  (figura \ref{fig:arquivodlis}). Você poderá decidir importar  \includegraphics[scale=1]{\importacaodedados documentarrowicon.png} ou não  \includegraphics[scale=1]{\importacaodedados documenterroricon.png} uma curva  apenas clicando sobre ela. Caso a curva selecionada represente o índice, o  programa lhe enviará uma mensagem sobre o estado da curva selecionada (figuras  \ref{fig:importarrenomearassociarsemanticaacurva} e  \ref{fig:curvadeindiceaserimportada}).  Assim como no importador de arquivos texto (ver item  \ref{sec:dadosprolab}), você tem a opção de visualizar apenas as semânticas  compatíveis às contidas nos dados, ou associar a unidade padrão da semântica  quando a curva não possuir unidades definidas. Você tem a opção de deixar que o  sistema sobrescreva os atributos dos poços, com valores encontrados no arquivo,  selecionando a check box na parte inferior a direita do ajudante de importação.  E se algum mapeamento estiver selecionado, curvas associadas a semântica  litologia serão automaticamente mapeadas durante a importação, ou seja, será  criada uma curva de litologia. Ao clicar sobre a combo box localizada na parte  inferior do ajudante de importação, chamada \textbf{mapeamento de litologias}  você terá acesso ao mapeamento default (padrão PETROBRAS) existente no  programa, ou outro existente. Após todas as definições realizadas clique em  concluir.     \begin{figure}[!h] \centering \includegraphics[scale=1]{\importacaodedados arquivodlis.png} \label{fig:arquivodlis} \caption{Arquivo Dlis.} \end{figure}


How to redefine \section{...} to include \textsc{...}?

I'm writing a rather extensive report in LaTeX in which I have some specific preferences for my section titles. For example, I want the titles to be in upper-case using the \textsc{..} command. If I include,  \usepackage[T1]{fontenc}   I am able write,  \section{\textsc{Some Section Title}} % works fine, however ...   My document is large and it would be really nice if I could redefine \section{} to automatically include \textsc{}. I'm happy to consider some other alternative to \textsc{}, if such exists.  Note that I have no experiance with the '\renewcommand', so working examples are much appriciated! Thanks!  Adding an MWE as requested,  \documentclass[12pt, twocolumn]{article} \usepackage[english]{babel} \usepackage[utf8]{inputenc} \usepackage[T1]{fontenc}             % ENABLES \textsc{} INSIDE \section{} \usepackage{mathrsfs,amsmath,amssymb} \usepackage{sectsty}  \renewcommand{\thesection}{\Roman{section}}  \renewcommand{\thesubsection}{\Roman{subsection}} \allsectionsfont{\centering}  % IMPORTANT: % Now, my section titles are centered, and have roman numbering. % .. but I would also like to have them written in upercase.  \title{The most awesome title ever!} \author{My name and stuff} \date{2014}  \begin{document} \maketitle  \section{\textsc{Section nr. 1}} % THIS WORKS, but ... Some text ...      \section{Section nr. 2} % I would like to write this with the same result Some text ...       \end{document}


Find the value of $\sqrt{1+\frac{1}{1^2}+\frac{1}{2^2}}+\sqrt{1+\frac{1}{2^2}+\frac{1}{3^2}}+...+\sqrt{1+\frac{1}{1999^2}+\frac{1}{2000^2}}$ I found the general term of the sequence. It is $\sqrt{1+\frac{1}{k^2}+\frac{1}{(k+1)^2}}$ So the sequence becomes $\sum_{k=1}^{1999}\sqrt{1+\frac{1}{k^2}+\frac{1}{(k+1)^2}}$ I tried telescoping but i could not split it into two partial fractions.And this raised to $\frac{1}{2}$ is also troubling me.What should i do to find the answer?


In one of my documents I used the  to illustrate a matrix multiplication but nowadays I get the error that shapes like A-2-1 are unknown. This is a known issue described in various questions because apparently some nodes get no names and \chainin fails or something like that. I was wondering how can I fix this issue in the specific example I have linked above to continue using the graphic.


Prove that if $a+b+c=1$ then $\frac{ab}{c+1}+\frac{ac}{b+1}+\frac{bc}{a+1} \le \frac{1}4$ $a,b,c$ are positive real numbers

I simplified the inequality , but I didn't get anything that may seem useful.  I got   $$^\sum_{cyc} 4a^2b+8ab+4ab^2\le abc+ab+ac+ab+a+b+c+1$$


In PCA, can the values in the principle component vectors which are close to zero be removed to see the important features?

In PCA, when I extract the principle component vectors, I am choosing the first vector with the largest corresponding eigenvalue. I notice that some of the values in this vector are close to zero. Can I reduce the size of this vector by excluding/removing the dimensions where the entries are close to zero?  My line of thinking is that if a component 'explains', for example 80% of, the variance and is a unit vector of 100 elements, and in this unit vector only a single loading (value in the vector) contributes as much as 90% of the total value making up a size of 1.   I would like to use PCA in a way similar to Lasso regression where the constraint on the total size of used variables is being minimized by some tuned parameter.


How do IP answer packets reach their destination inside of a private LAN?

This is a little theory question that has been confusing me for a pretty long time.  Basically, if we are inside of a private LAN, and we want incoming packets to reach, for example, an HTTP server located on one of the machines, we forward ports so that incoming packets reach exactly that computer.  Now, I'm quite confused as to how 'response' packets reach their destination inside of a LAN, like, when we open a web page or so. Can't really find any useful information on that topic.  I hope someone can give me a couple of clues or link me to some information that might explain it. Thanks.  EDIT: I think I should clarify. An example of what I'm asking would be something like this: 1. A computer inside of a LAN with a single external IP tries to load a web-page from a web-server outside of this LAN (Basically on the Internet) 2. The web-server responds and sends the web-page back to that computer.  What quite confuses me at this point is, how does the router know what computer to send the incoming data (given the router is connected to a LAN with multiple computers) without previous port forwarding.


Let $I=\int^1_0\frac{\sin x}{\sqrt x}dx$ and $J=\int^1_0\frac{\cos x}{\sqrt x}dx$. Then which of the following is true?  $I > \frac23$ and $J > 2$ $I < \frac23$ and $J < 2$ $I < \frac23$ and $J > 2$ $I > \frac23$ and $J < 2$   I tried to do it using the small angle assumption and also by graphical method. The correct answer is Option 2.


I am trying to read a line in a file and set a string equal to that and write it to a file FileOut.   I am currently reading all lines before this to get to the line needed as follows;  FileInputStream TempIn = new FileInputStream(TempOut); BufferedReader br = new BufferedReader(new InputStreamReader(TempIn)); for(int i = 0; i < totalNumberOfCaves+1; i++) {     br.readLine(); } String tempRoute = br.readLine(); br.close();  BufferedWriter writeRoute = new BufferedWriter(new FileWriter(FileOut)); writeRoute.write(tempRoute); writeRoute.close();   However I am getting an error staring  Exception in thread "main" java.lang.NullPointerException at java.io.Writer.write(Unknown Source) at Dijkstra.main(Dijkstra.java:169)   Line 169 relates to the following writeRoute.write(tempRoute);  I am unsure as to why I am getting this error, any advice would be appreciated.  Thanks.


Why did Edmure Tully agree to this plan?

was set free by Jaime. He could have just held the Riverlands.  Yet he chose to go back in his cage and betray his own men to ensure that his child could live.  That's kind of idiotic isn't it?  His son, whom he never saw, is  Walder Frey's grandson. He shouldn't fear that they will murder his son. Yet he takes a much greater risk and forgoes his freedom just so Jaime doesn't murder his son.  If I were him, I'd just enjoy my freedom and father more sons on other women than Roslin Frey.


I am currently making a game in C# using Direct X 9.0. The game remake is Donkey Kong NES. I have nearly everything completed, but I am having problems with the physics of Mario's jump. I have variables declared for the Y and X co-ordinations.  I was wondering if there was a simple method of doing this. I have searched high and low for an answer but the answers I have found are either irrelevant/ or using a different programming language such as XNA.  I currently have a bool variable set to check to see if W has been pressed then that will trigger any code to make him jump. I have been messing around such as.    if (jump == true)     {          Playerypos -=  vel;         Playerxpos +=  vel;     }   Which didn't work that well. I have searched high and low for an answer and now I am desperate, if someone could point me in the right direction to a simple solution. That would be great. Much appreciated for any responses.


Error when I boot my Laptop PC in Ubuntu  This error shows up when I boot my PC. I'm using dual boot system and the version is Ubuntu 20.04 LTS. My Ubuntu is stored in my HDD and my Windows OS is in SSD which works perfectly fine. I have very important files in my Ubuntu. Please tell a way to fix this issue. This happens every time when I boot up my PC in Ubuntu. Thanks in advance.


print custom image field for taxonomy page (page--taxonomy.html.twig) template

How do I load an image from a taxonomy custom field into a custom location on the taxonomy page template?  It's easy to accomplish it when the image is in a node. The following code works for images, but it doesn't work for taxonomy pages.      {{ file_url(node.field_reference_background.entity.uri.value) }}   How can I accomplish the same for taxonomy pages?


Let $U$ be an open, bounded connected domain in $\mathbb{R} ^n$. Define $U_\epsilon=\{x\in U|dist(x,\partial U)>\epsilon\}.$ Can $U_\epsilon$ be unconnected? Anyone has example for that?


is there a tutorial and patterns to write unit tests in Unity ?  Should we use the classical c# way and test the code or should we test the interactions in UI ? If so how?


Difference between irreversibility and entropy?

recently wrote an  on  in collisionless , where at least one topic discussed confused me.  Besides discussing the issue of how a process can be microscopically  and macroscopically , he mentions something regarding a "entropy-preserving relaxation mechanism" that is irreversible.  Am I missing something?  I think the article is suggesting that something can preserve entropy but still be irreversible.  This begs the following questions:   Are  and irreversibility synonymous? Or are they distinct entities each with their own fundamental properties?


Prove that if $\sum_{n = 1}^{\infty} a_{n}$ converges, then $\sum_{k = 1}^{\infty} A_{k}$ converges(2)

Suppose that  $\{a_n\}$ be a sequence of real numbers.let $\{n_{k}\}$ be an increasing sequence of positive integers, and let $A_{k} = a_{n_{k}} + a_{n_{k}+1}+ ... +a_{n_{k +1}-1}$, for each $k \in \mathbb{N}$. Prove that if $\sum_{n = 1}^{\infty} a_{n}$ converges, then  $\sum_{k = 1}^{\infty} A_{k}$ converges. Give an example to show that the converse is not true.  Can anyone explain for me in the term $a_{n_{k+1} -1}$ in the definition of $A_k$ we take a decreasing index (i.e why we subtract 1 and not add 1 to $n_{k+1}$ as we continued adding 1 to $n_{k}$ ) or this is a typo?  Also can anyone give me a numeric example for the direction we want to prove ?  Also I received a hint about the proof that I should use Cauchy criterion, could anyone provide me with a little bit more details in this direction?  Those are related links:  1-   2-  Thank you!


Why can't users with less than 100 reputation answer their own question sooner than 8 hours after asking?

Yesterday I  and after 2 hours I found a "solution", I would answer, for the first time, at my question and Stack Overflow block my answer with this message:     Oops! Your answer couldn't be submitted because:           Users with less than 100 reputation can't answer their own question for 8 hours after asking. You may self-answer in 5 hours. Until then please use comments, or edit your question instead.)      and I would want to understand why there is this block?  Yesterday I worked around it by adding on my question a block [answer]answer[/answer] as shown at screen shot below and today I modified again the post moving the block out into an answer but, for me, it is strange to have self-answer block.  EDIT: because Cody and Rory ask why I add the tag [ANSWER] on my question the answer is simple: I didn't know how tell that I resolved the problem so I create that tag for underline that it was out of my question and temporarly there...


How can I display the welcome message "welcome panni" every time I log into unix?


'90s kids movie about a game robot attacking people

I'm looking for a movie that was set in the US, and all the characters (including the robot) spoke English.  I can't recall the exact plot, but mostly it was about an innocent game robot that shoots small objects for fun and becomes dangerous, because its AI made a wrongful choice about 'winning the game'. The robot starts to arm itself with more dangerous objects (not sure but knives and stuff) and starts to attack people.  It was overall supposed to be fun and adventure movie for kids. Color movie, and probably made in 80~90's.   There is a recurring scene when the robot detects an aggressor, it scans and loudly announces "enemy one, enemy one". The robot was somehow looking similar to Wall-E, and had a saucer-like head part.


Grammatical number of "a specified number of people"

In this sentence, which is correct, is or are?     We will not stop operating until a specified number of weak events [is/are] detected.   My feeling is that the verb should agree with number, not events, thus I'd use is. But there is disagreement here at work.  Also, what is the name of the phrase "of weak events" in this sentence? If I knew that to begin with I'd probably have been able to look up the answer.


How to find Oracle's installed version and release from a program?

I need to determine from a program what version of Oracle is installed in each of the Oracle Homes on a server.  As there may not be any databases created in the Home yet, I need to be able to do this outside of the database (i.e., without connecting to the database).  Also, it would be highly preferable to be able to do this from a remote program.  This is from a windows program running .Net (C#, if that matters).  I am currently reading remote registry keys (using this technique: ), to find all of the Oracle Homes according to .  This works fine, however, I have looked around those keys and do not see any information on the exact version/release.  The name of an Oracle Home itself is of course 1) not a reliable indicator and 2) does not have the exact version/release (for instance "10.2.0.4.0").  Basically I am looking for a way to figure out what the Oracle Universal Installer tells you in the Installed Products button.    I should clarify, all of the Servers will be running Windows 2003-2008.


Algebraic proof that $\det AB = \det A \cdot \det B$ using Leibniz formula for determinants

The  allows us to express an $n \times n$ matrix determinant as a sum over permutations in $S_n$:  $$\det A = \sum_{\sigma \in S_n} \operatorname{sgn}(\sigma) \cdot \prod_{k=1}^n a_{\sigma(k), k}$$  A surprising amount of properties about determinants can be proven from this formula alone, using algebraic manipulation and basic facts about permutations. (Particularly, it's simple (and fun) to use it to show what happens to the determinant of a matrix when you apply elementary row operations; try it!)  Is there an existing proof of the fact that $\det AB = \det A \cdot \det B$ for $n \times n$ matrices $A$ and $B$, relying only on algebraic manipulation of the above formula? The resulting sums get rather ugly:  \begin{align*} \det A \cdot \det B &= \sum_{\sigma \in S_n, \tau \in S_n} \operatorname{sgn}(\sigma \circ \tau) \prod_{k=1}^n a_{\sigma(k), k} \cdot b_{\tau(k), k} \\ &\stackrel{\color{red}?}{\color{red}=} \sum_{\sigma \in S_n} \operatorname{sgn}(\sigma) \prod_{k=1}^n \left( \sum_{x=1}^n a_{\sigma(k), x} \cdot b_{x, k} \right) \\&= \det AB \end{align*}  How would I go about trying to prove that these expressions are equivalent?


I have a fully-configured instance and an image from that for an autoscaling group. When autoscaling new instances from this image, it calls cloud-init. cloud-init changes the hostname and breaks fstab.  I want to prevent cloud-init from starting on instance launch.


Windows CMD: "dir *.cpp" wildcard matches "main.cpp_" and "main.cpp2"

Here is the content of the directory:  λ dir /b "..\src\" main.c main.c_ main.c2 main.cpp main.cpp_ main.cpp2   This works as expected:  λ dir /b "..\src\*.c" main.c   This doesn't:  λ dir /b "..\src\*.cpp" main.cpp main.cpp_ main.cpp2   Why does this wildcard match main.cpp_ and main.cpp2?  What is a working solution to list only *.cpp files in a directory?  EDIT: it is not a duplicate of


Why is the number of integers between $2$ integers not their difference?

Helping my kids in 3rd grade Math class today.  We were rounding to the nearest $10$. So for $100$, the numbers that round to it are $95$ to $104$. $95, 96, 97, 98, 99, 100, 101, 102, 103, 104$  which are 10 numbers I asked how many numbers round to $100$ one kid says 9, I say 10.     Why is $104-95=9$ not the correct way to figure out the number of numbers?   What is the correct equation, if there is one?


Has anybody converted from Nikon to Canon and continued to use their Nikon Lenses with adapters, and how did that workout - as far as focus, aperture, ISO, and fitment.  My wife has many Canon Lenses and I have a D200 so we have 2 times the lenses in most cases with a few Nikon DX (APS-C sensor dedicated) lenses - without considering the full frame scenario and lens compatibility.  Considering switching but losses seem certain if I have to sell all my Nikon lenses, was wondering if there would be a best type lens to keep - Auto Focus and  Aperture.


Can you use thieves' tools to construct locks and traps, or do you need heavier tools?

So in D&D 5th edition, one can make a character with a background, e.g. a guild artisan who does locksmithing.  Obviously a locksmith is very good at picking locks, even if he has no levels in the Rogue class.  In this example, consider a guild artisan locksmith who becomes a cleric of Gond, god of craftsmanship.  The PHB doesn't get very specific, but a non-Rogue guild-artisan locksmith character who starts out might get (10 pounds of)  "tinker's tools" or (1 pound of) "thieves' tools."  For adventuring, you could say that the locksmith just takes thieves' tools because they are lighter to carry, but probably that wouldn't be enough to construct a new lock, much less a new trap.  Assuming that the locksmith-adventurer plans to construct new locks (and possible new traps) while in a dungeon, presumably he would need to bring along lots of spare parts, and thus he would have to carry a tool kit at least as heavy as "tinker's tools."  Given earlier questions such as:   I suspect that the rules are not very precise about whether player-characters with a locksmithing background can construct traps while in a dungeon.  From my guesstimate, I would say that they would need to negotiate with the DM to make sure the action is allowed in that DM's campagn.  Am I missing some clear rule on lock-and-trap construction, or did the rule designers just leave it open to interpretation?


Can Hogwarts prefects dock points or not?

In The Chamber of Secrets, Percy - a Gryffindor prefect - docks 5 points from Harry, Ron and Hermione for lurking in a girls' bathroom. In The Order of the Phoenix, however, Draco states that prefects cannot in fact dock points from students:     I know prefects can’t dock points, Weasel King. But members of the Inquisitorial Squad –   I'm just a bit confused. Is this just sloppy writing or did the rules change?


I have some cron jobs set up to run, some of them each minute. I know I can log them to text files by simply putting php /path/to/file.php > /var/logs/something.txt but can I do this every minute? The nature of the log's output means that the log file will be very small, but I don't know how to log each minute's output to a separate file.  Thanks


Find the approximate center of a circle passing through more than three points

Consider n point $(x_1,y_1), (x_2,y_2),\ldots, (x_n,y_n)$. For $n = 3$ it is easy to find the center of the circle passing through the three points. I wanted find the approximate center of the circle passing through more than three points.   The application is as follows. I have circles on a sheet of metal. I can poll different points on the circle to get the their co-ordinates. By polling three points on every circle I can predict the co-ordinates of the center. But I wanted to improve the accuracy of the prediction. A Google search reveals only the center of the passing through three points.  Edit 1: In response to Hoda's comment, I am adding that the measurements related to the points on the circle have errors. The objective is to minimize the error in the position of the center by polling more points on the circle.


How do i compare ordinal score across two or more categories?

I have an ordinal score ranging from ( 1 to 5 ) called "Score"   I have another binary variable Human Response (Yes or No ) called "h_score"  I don't think i can do correlation study in this case as the h_score isn't numeric or ordinal and hence correlation doesn't make sense.   How do i analyze if there is difference in distribution of score across h_score ? Can I use chi square test ?


If $m,n\in N$ Prove that there is such a positive integer k, such that $(\sqrt{m}+\sqrt{m+1})^n=\sqrt{k}+\sqrt{k+1}$ I attempted to solve this question using binomial coefficients, saying: $(\sqrt{m}+\sqrt{m+1})^n=\sqrt{k}+\sqrt{k+1}=\sum\limits_{a=0}^n {n\choose a}*\sqrt{m}^{n-a}*\sqrt{m+1}^a$ and from here I was thinking that I had to do something with $\sqrt{m}^{n-a}$ with $\sqrt{k}$ and do something else with $\sqrt{k+1}$ and $\sqrt{m+1}^a$. Unfortunately I couldn't think of what to do with this circumstance. I then thought of maybe taking $(\sqrt{k}+\sqrt{k+1})^2=(\sum\limits_{a=0}^n {n\choose a}*\sqrt{m}^{n-a}*\sqrt{m+1}^a)^2$, but this immediately over-complicated the question. Could you please explain to me how to solve this question and how to solve similar questions in the future?


Is it possible to prevent DHCP service on SBS 2003 from shutting down due to rogue DHCP server?

We are using LogMeIn Hamachi to link two remote sites together by VPN.  This is working perfectly, the only problem is that the DHCP service on our SBS 2003 server shuts itself down after an hour or so of Hamachi being enabled, as it identifies the virtual DHCP server on the Hamachi gateway PC and believes it is a rogue DHCP server.  Hamachi is not installed on the SBS server, but on a regular Windows XP machine on the same LAN.  As far as I can see, the Hamachi virtual DHCP server is not really a rogue DHCP server in this scenario. No client on the LAN will ever get an IP address from Hamachi (same subnet but different, non-overlapping DHCP scopes) however, it's obviously not doing something right because the server's DHCP service does not want to coexist with it.  Does anyone know of a way to prevent the DHCP service on the SBS 2003 server from shutting down if it believes it sees other DHCP servers on the network? I want to treat this as a false positive and see what happens if we ignore it- there is no way for IP conflicts to happen due to the non-overlapping IP scopes.    I don't quite understand how a DHCP server with IP 192.168.1.50 can conflict with one on 1.0.254.169..... that's not even the same subnet!


Why was my flag declined for this question

Just a simple question. I flagged this question as low-quality because thats what it is. I do not need to elaborate and call it off-topic or anything. However my flag was declined. May i know the reasoning?   This was the reason for my flag being declined "declined - a moderator reviewed your flag, but found no evidence to support it"


How to know post time of pic in instragram?

I am trying to get the post time of picture instagram by C#. For example i got the next string from the server (JSON):   {"created_time":"1447156299","text":".........} what is the time?


Intuition/Real-life Examples: Pairwise Independence vs (Mutual) Independence

Would someone please advance/discuss some real-life situations falsities $1, 2$? I'd like to intuit why these are false. As a neophyte, since I still need to compute the probabilities for the examples in the two answers to apprehend them, I haven't naturalised these concepts yet. Thus, I beg leave to ask about other real-life examples which require less or no computations.  I tried and would appreciate less numerical examples than  and , and  Examples 1.22 and 1.23 on P39 of Introduction to Pr by Bertsekas.  $1.$ Pairwise Independence $\require{cancel} \cancel{\implies}$ (Mutual) Independence.      $2.$ Pairwise Independence $\require{cancel} \cancel{\Longleftarrow}$ (Mutual) Independence.         P38 defines (Mutual) Independence :    For all $S \subseteq \{1, ..., n - 1, n\} $ and events $A_i$, $Pr(\cap_{i \in S} A_i) = \Pi_{i \in S} A_i.$


Can anyone help me to find out which version of Ubuntu we use?

I need to be able to find out what version of Ubuntu we are using. I have no IT person who can help anymore. Can anyone help please?


How do you fix the passive voice in this sentence

I wrote this sentence:  Because of his low weight, Gabe was still being nurtured instead of being named.  And Word underlined the bold part saying I was using passive voice and I don't know how to fix it.  Passive voice is not part of the assignment, but I need two prepositional phrases.


I'll add some quotes from the , as it wouldn't get clearer if I quoted everything from the book. The quotes which I'll take from the book won't have any page number, as it varies from edition to edition. In The Restaurant at the End of the Universe, Zaphod, Trillian, Arthur, Ford and Marvin travel in the black ship  belonging to the rock band Disaster Area (Wikipedia)  back in time:  "We're plummeting back-ward through time." (Ford in Chapter 20)  However, they travel too far back in time:  "[...] If it is what I think it is, and if it's saying what I think it's saying, then we've already gone too far back into the past. Maybe as much as two million years before our own time." (Ford in Chapter 20)  Shortly after that, they end their time travel (so they're now two million years before their own time). They then realize that they should get off the ship and use the teleporter to do that, leaving Marvin behind:  There is a teleporter on the ship for which the guidance system was never built, as it was never intended to be used, and it also requires somebody to stay on the ship to operate it. Marvin is chosen to stay behind and teleport the others, who have no choice but to go wherever it takes them. (Wikipedia)  With Arthur and Ford the following happens:  The teleporter has meanwhile sent Arthur and Ford to the Golgafrinchan Ark Fleet Ship B, a ship of fools, which crash-lands on prehistoric Earth. (Wikipedia)  which makes sense, as they're two million years before their time, so the earth is two million years before it's time as well. What doesn't make sense however is what happens to Zaphod and Trillian:  Zaphod and Trillian are returned to the Heart of Gold, which is commandeered by Zarniwoop to complete his mission, to discover who really rules the Universe.  Because this means, that Zaphod and Trillian were teleported into their own time, as Zarniwoop and the Heart of Gold didn't exist two million years before their own time. It's the same with Marvin, who somehow made it off the ship as well (I forgot how and it's not quite relevant), who then was on a different planet, where the Krikkit robots found him and took his leg - once again in the normal time, not two million years ago. Am I not seeing something which explains this or did Adams simply make a mistake here?


How to get network, memory and CPU status on Bionic GNOME panel (system menu)?

I miss the old , which allowed me, at a glance, to see network activity, memory status and CPU activity.    How do I get something like this back on Bionic Beaver (GNOME on Wayland) ?


How to know which license version has an XP installed system

My friend has a notebook with Windows XP Professional installed. I would like to understand which version exactly is and which license type is referred to. The sticker reports an OEM pre-installed XP Home Ed, so I just get infos by read some file or some pop-up by launch a command. For example I can read the serial number from system proprieties. I also can extract product key used for activation.  My goal is to provide all needed infos to, in case, be able to borrow the right version of WinXP CD and reinstall/reactivate the system on the same machine, reusing current extracted product key.  So I'd like to know which version is installed (localization included) and which CD version of XP I need to reuse its working product key.  Thanks in advance!  :)    EDIT  to explain why this question is not solved by answers of suggested topic ():  c:\windows\system32\prodspec.ini   on our system is just empty, I saw that answer before posting, thanks anyway for suggest.    EDIT2  In reply to who talked about absence of COA. If one loose an old CD with its COA sticker, his system remains still genuine. I think it should be possible to obtain info about license version from an installed system in that case, just it. This topic is not to discuss about cracking or so on. We have a system installed. We want to know more info as possible about its version and license version. That's all, nothing more.  Thanks for all your answers, even if I think they are not completely exhaustive, anyway... thanks again


I have an Early 2015 MacBook Pro running OS X 10.11.6 (the latest version of El Capitan) that as of late had started randomly opening a website with the link fastlauncher.xyz [Thanks John Ramos: wouldn't be a good idea to try going to the link.] It does not happen often.    I have tried:   to use the latest version of Malwarebytes Anti-Malware for Mac; it did not detect the adware.  checking the browser extensions for Safari and Chrome, the two browsers I use; but do not see anything suspicious.  checking for Login and Startup Items, nothing suspicious restarting (I'm getting a bit desperate and maybe it'll work - it didn't) using BitDefender (30-day trial); solved the issue   I have not tried:   using only one browser and seeing whether the adware will go away (hence I am unsure whether it is a system virus or isolated to a browser)   So far, the link has only been opened in Chrome. I would prefer manual removal over a program. Will update this list as I go.


Why not make  but for questions too?  I love that everything is well though behind SO but I can't see no reason as to why great questions can't be prized with "Badges by subject".


What's the best way to deal with zero-area faces that break normals

I run into this issue all the time and it's really frustrating to fix especially on high poly meshes. Either there's no face joining some edges ("zero-area hole"?) or there is a zero-area face. Either way it messes with the normals making ugly black spots all over the mesh. Here's an example:    To fix the normals I'd quite like to either...   split the upper face, as the dashed line shows, or merge the two lower faces by dissolving the edge, as the cross shows.   How can I do this automatically to the entire mesh?  Manual methods aren't acceptable as there's a lot of this kind of geometry. I'd prefer to change the mesh as little as possible, or at least not lose any information by collapsing huge areas.    Sometimes is's hard to actually select the face and I resort to selecting an adjacent one, growing the selection with Ctrl Numpad+ and deselecting the others. Once selected, others can be selected with Select->Select Similar->Area. Adjusting the threshold is often necessary to avoid numerical inaccuracies. It also helps if the model is not too small, so maybe scale it up first.  Below is an example of a zero-area hole, although I've moved the vertex up so you can see it.    You can get the zero-area faces back with Mesh->Clean up->Fill Holes.    Even if I do manage to manage to get rid of the zero-area face, leaving a quad as shown below, I've found triangulating it splits the wrong way and just gives a zero-area face again (this really seems like a bug in blender's triangulation).


I am using MiKTeX 2.9 on Windows 7.   I'm getting the error: "can't write on pdf file."  The pdf doesn't reflect what I wrote.  What did I do wrong?  My input:  \documentclass[12pt]{article} \usepackage{epsf} \usepackage{amssymb} \usepackage{graphicx} \usepackage{setspace} \usepackage{amsmath} \usepackage{rotate} \usepackage{endnotes} %\usepackage{harvard} \usepackage{vmargin} \usepackage[nolists,noheads,tablesfirst,nomarkers]{endfloat} \usepackage{natbib} \bibliographystyle{apsr}  \oddsidemargin=1.0in\evensidemargin=0.in \textheight=8.5in\textwidth=6.6 in \baselineskip=18pt \parskip=6pt  \begin{document}  % added, was missing  TEXT  \newpage \baselineskip=12pt \doublespacing  \bibliographystyle{apsa} \bibliography{Dissertation_Proposal}   \end{document}


This code was written in Scala.  Is it possible to write it in Python using built-in functions?  Scala Code:  List(1, 2, 3, 4, 5, 6, 7, 8, 9).grouped(4).toList.map { group =>     println("begin")         group.map { item =>             println(item)         }     println("end") }   Result:   begin 1 2 3 4 end begin 5 6 7 8 end begin 9 end   I tried, but didn't succeed.


Why don't files from Xbox 360 show up when USB drive is plugged into computer?

I'm using a Lexar JumpDrive S73 32GB USB flash drive. I've configured it on my Xbox 360 and got a message saying it's compatible and meets the standards, but when I plug in it in my computer no files show up, even in Horizon.   After the driver was installed, both the USB mass storage and Lexar JumpDrive USB device were ready to use (installed properly), but it said no driver found for Xbox 360.    I tried looking for some sort of driver (which sounds silly) but I couldn't find anything.  I'm attempting to mod Minecraft on my Xbox and I don't want to buy another USB.


What I'm trying to achieve   Clone a div and add it below the existing div(s) - jQuery 1 below ...in the div that is being cloned, I already have another jQuery running that shows/hides a child div based on a checkbox - jQuery 2 below   Issue Cloning works fine. However, I can't get the show/hide based on checkbox to work  Question Is this possible to do through jQuery? It seems like jQuery 2 doesn't understand that, post-cloning, there's a new div that also would like the same functionality of showing/hiding the child-div based on the checkbox.  jQuery 1  $(document).ready(function() {   var i = 0;     $('.button-add').click(function(){         $i = i++;         //we select the box clone it and insert it after the box         $copy = $('.copybox:first').clone();         $copy.find("input:checkbox").attr("data-related-item","hideconfig"+i);         $copy.find("div#hideconfig").attr("id","hideconfig"+i);         $copy.insertAfter(".copybox:last");     });      $(document).on("click", ".button-remove", function() {         $('.copybox:last').remove();     }); });   jQuery 2  function evaluate(){     var item = $(this);     var relatedItem = $("#" + item.attr("data-related-item"));      if(item.is(":checked")){         relatedItem.fadeIn();     }else{         relatedItem.fadeOut();        } }  $('input[type="checkbox"]').click(evaluate).each(evaluate);


How many points in RSA, such that $m^e = m \bmod n$

For every RSA-cryptosystem, there exist some messages $m$, for which it holds that $m^e \equiv m \pmod n$ As to the question, how many such messages exist, this question has already been asked and answered here:  However, I do only understand the answer up to a certain point Suppose that $n$ is only 1 prime. Then it holds that the number of unconcealable messages is $\gcd(e-1, p-1)+1$ This is because in $m^e \equiv m \pmod  p$ , either $m = 0$ or $m \not= 0$. In the latter case $m$ can be expressed as $g^t$, where $g$ is a Generator in $\mathbb{Z_p}$ $g^{t*e} \equiv g^t \pmod p$ $g^{t(e-1) \bmod p -1 } \equiv g^{0 \bmod p -1} \pmod p$ $t(e-1) \equiv 0 \pmod {p-1} $ has exactly $\gcd(e-1, p-1)$  solutions, so the total number of unconcealable messages is, together with $m=0$ , $\gcd(e-1, p-1)+1$ When we now look at real RSA, which has two prime factors in its modulus, it holds that the number of unconcealable messages is $(\gcd(e-1, p-1)+1)\cdot(\gcd(e-1, q-1)+1)$ Why is that so? I suppose it has to do with CRT, but I just cant understand why.