Is it possible to prove the distribution axiom of modal logic? I have proven all the conclusions of propositional modal logic using this axiom, the definitions of the four standard modal operators, and the postulate that some contingent proposition is true. I wanted to know if it was possible to prove this distribution proposition (also called Kripke property):   $$ \square (p \rightarrow q) \rightarrow  (\square p \rightarrow \square q)$$ It basically distributes the necessity operator over the components of every necessary conditional proposition. Most modal logic books accept this as an axiom in addition to others, but I want the fewest axioms possible as I have already reduced them to the distribution axiom, modal semantics and definitions, and (some contingent proposition is true). Is there any further reduction possible by proving the distribution axiom. And if so please provide a natural deduction proof of this distribution statement from previous principles in modal logic.


How do I make Cedilla (ç) character available in English USA?

I need the character Cedilla working my English USA Ubuntu Natty but when use the normal combination ' then c I get this ć. In the previous versions I used this solution:  but it isn't working on Natty. Any help will be very appreciatted! Best regards.


datetime.parse and making it work with a specific format

I have a datetime coming back from an XML file in the format:     20080916 11:02   as in      yyyymm hh:ss   How can i get the datetime.parse function to pick up on this? Ie parse it without erroring? Cheers


Is $S_n$ semidirect product of $A_n$ and $\mathbb{Z}_2$?

A similar question is asked by some user but unanswerd ().  I wants to show that the semidirect product of $A_n$ and $\mathbb{Z}_2$ is the symmetric group $S_n$.      $S_n\cong A_n \rtimes \mathbb{Z}_2?$   I tried a lot but I have seen that $A_5\rtimes \mathbb{Z}_2\cong $SL$(2,5)$. Please tell whethere I am correct or not?


How do I make sure my RAW files are readable in the future?

I've recently started to use RAW with Lightroom. I'd like opinions on how I should make sure my images are readable (not necessarily editable) a few years hence. Heck, let's say a decade some decades.  Should I keep my archives in Nikon's raw format, in conjunction with the LR database? Should I convert them to TIFF? How about DNG?


How do I use a variable in condition section of a bash for loop

The for loop does not work if I use the $DAYSDIFF variable but it does work if I type in the number of days since 2020-01-21. When I use $DAYSDIFF, I get an error date: invalid date ‘2020-01-21 + {0..97} day’ Is there a way to use the calculated number of days variable in the "IN" clause of the loop? I'm using Ubuntu 18.04.  REPDATE=2020-01-21 #Date of first COVID-19 report. CURDATE=`date "+%Y%m%d"` #Todays date. DAYSDIFF=$(( (`date -d $CURDATE +%s` - `date -d $REPDATE +%s`) / (24*3600) )) #echo $DAYSDIFF #The correct number of days is echoed. REPORTNUM=1  for i in {0..$DAYSDIFF} #DAYSDIFF is not working. If I type a number here it works. do    NEXT_DATE=$(date +%Y%m%d -d "$REPDATE + $i day")    echo wget https://www.who.int/docs/default-source/coronaviruse/situation-reports/"$NEXT_DATE"-sitrep-"$REPORTNUM"-covid-19.pdf    #wget https://www.who.int/docs/default-source/coronaviruse/situation-reports/"$NEXT_DATE"-sitrep-"$REPORTNUM"-covid-19.pdf    REPORTNUM=`expr $REPORTNUM + 1` done


How do I make my Ubuntu 18.04 LTS desktop look like this?

How to make my Ubuntu 18.04 LTS desktop look like this?


I have also seen Silhouettes of weedle and seedot, sableye. I already have these

In the nearby list you can see sableye is a silhouette I have that one already and don't understand why these pokemon are  up like this.


Integrate $\iiint_E z\,dx\,dy\,dz$ in $E=\lbrace(x,y,z) : x^2+y^2+z^2 \leq 4, z \leq 1 \rbrace$

I want to integrate $\iiint_E z\,dx\,dy\,dz$ in $E=\lbrace(x,y,z) : x^2+y^2+z^2 \leq 4, z \leq 1 \rbrace$. I want to split that triple integral in 3 integrals, but I don't see which the limits are. I guess I have to do $x \leq \pm \sqrt{4-y^2-z^2}$ and integrate in $x$ between those limits (I don't know if this is correct) but then I get lost with the $y$ limits. If I let $z$ be the last variable I integrate, I suppose I can say that $z$ is between $-2$ and $1$, so that limits are easy. What are the limits of the $y$ integral? And are the $x$ limits okay? Thanks in advance.


The XBox360 is offline. I was very far in the missions. How do I save game in Grand Theft Auto 5?


Add command line support to Winforms application

i have changed my Main:  [STAThread] static void Main(string[] args) {     if (args.Length == 0)     {         Application.EnableVisualStyles();         Application.SetCompatibleTextRenderingDefault(false);         Application.Run(new fForm());     }     else     {         Console.WriteLine("Yay! I have just created a commandline tool.");     } }   But how can i print this massage Console.WriteLine(...) ? currently nothing happen when send argument into my exe file


My model is not showing correctly in the viewport

I´ve been working on this model for some time now, i added some materials and added light, it had been working just fine , until i loaded the project today and my model is now like this... Thanks for the attention.


'on a null object reference' error logged

@Override     public void onFragmentSelected(int position, Bundle bundle){         Fragment curFragment=null;          if(position==0){             curFragment=fragment1;             toolbar.setTitle("first page");         }else if(position==1){             curFragment=fragment2;             toolbar.setTitle("second page");         }else if(position==2){             curFragment=fragment3;             toolbar.setTitle("third page");         }          getSupportFragmentManager().beginTransaction().replace(R.id.container,curFragment).commit();     } }  I'm learning android with a book. I wrote right same to the code of a book. but, it doesnt' work in a partial code, I exactly pass that strings "first page" ~ "third page" but, error occured... the eroor is lke that my title 'on a null object reference' I tried something that I deleted that three code(toolbar.stTitle();). and it worked. I don't know why. help me...


Round gdal_translate AAIGrid output to 4 decimal places

How can I use gdal_translate for AAIGrid so that the raster values are not more than 4 decimal places.


How can I verify that the Pauli group is a group? And is it abelian?

So how can I verify that the Pauli Group is a Group? Then furthermore, Abelian? And then to sum it up, the order of the group. Trying to do some research into the group but I can't find much about it.


Removing phantom display screens in Windows 10

I usually work with 2 additional display monitors with my Windows 10 laptop. I see 4 additional displays phantom screens in the display settings. The detect or disconnect this display doesn't work as well.  Even if I remove all the displays, I still 4 additional display. How should I remove those. I don't have or use the New Desktop in the Windows 10 when do WIN + TAB


Does anyone know how to install a new serial on a working copy of Windows 7 - I get notified that my software is not genuine but cannot reenter the serial


Add an android widget to the Stack Exchange app

I'd love a scrollable widget that displayed the feed, possibly customising what was shown (i.e. hot questions, unanswered, rep changes, badge notifications etc.) globally or per-site.  Ideally each entry would be clickable in the widget, opening up the SE app to the relevant screen.


What does the interval $]-\frac{\pi}{2},\frac{\pi}{2}[$ mean?

It could be a misprint or typo in what I'm reading, but I just want to make sure.  I'm reading Loring Tu's "An Introduction to Manifolds", and at the end of the first chapter, one of the problem states:  $\textbf{1.3 A diffeomorphism of an open interval with}\,\,\mathbb{R}$  Let $U\subset\mathbb{R}^n$ and $V\subset\mathbb{R}^n$. A $C^\infty$ map $F: U\rightarrow V$ is called a diffeomorphism if it is bijective and has a $C^\infty$ inverse $F^{-1}:V\rightarrow U$.  (a) Show that the function $f: \,\,\,]-\pi/2, \pi/2[\rightarrow \mathbb{R}, f(x)=\tan(x)$ is a diffeomorphism.  To be clear, I'm not asking for help with the problem, just the notation he uses. Elsewhere in the text, it appears that every time he mentions an open interval, he uses this $]a,b[$ notation, but for closed intervals he uses the traditional $[a,b]$.  Is this notation commonly used, or likely some sort of misprint with the pdf I'm reading from?


I just portscanned my system with nmap and got the following result:  PORT    STATE SERVICE 25/tcp  open  smtp 631/tcp open  ipp   what are these services and how i do disable them? probably i don't need them.


How to prevent bash from running when variable is undefined

#!/bin/bash        $myval=/home ls $mval <- unexpected misspelling  Is there a way to stop the ls command from executing since $mval is not defined? NOTE that this can not be checked for existence because it was a typo. I am looking more for a property that can be set.


Evaluate the integral   $$\int\frac{1}{x^2\left(x^4+1\right)^{3/4}}\,dx$$   My Attempt:  Let $x = \frac{1}{t}$. Then $dx = -\frac{1}{t^2}\,dt$. Then the integral converts to   $$ -\int \frac{t^3}{(1+t^4)^{3/4}}\,dt $$  Now Let $(1+t^4) = u$. Then $t^3\,dt = \frac{1}{4}du$. This changes the integral to  $$ \begin{align} -\frac{1}{4}\int t^{-3/4}\,dt &= -u^{1/4}+\mathcal{C}\\ &= -\left(1+t^4\right)^{1/4}+\mathcal{C} \end{align} $$  So we arrive at the solution  $$\int\frac{1}{x^2\left(x^4+1\right)^{3/4}}\,dx = - \left(\frac{1+x^4}{x^4}\right)^{1/4}+\mathcal{C.}$$  Question: Is there any other method for solving this problem?


What niche is the mobile app meant to fill?

So, I've been giving the mobile application a while for the last week or so, and I'm thrilled to be able to give feedback and report bugs on it.  I'm also thrilled that I can use the Stack Exchange network on my mobile, or tablet!  After about a week, though, I started to realize a few deficiencies in the application - some of which I've already reported as bugs, some of which are already reported, and some of which I'm not sure I should report, since I don't know what role this application is meant to serve.  So, I consider myself a bit of a power user of [Meta]StackOverflow.  I ask questions (at least on Meta), write answers, comment, but the bulk of my time spent on SO isn't geared towards that - it is, more times than not, flagging content, reviewing content, editing content, and otherwise consuming content.  The mobile application is certainly geared towards producing content and consuming content.  It does a fine job of that (although there are some rough cuts).  What I find myself doing, more often than not, though, isn't directly related to production or consumption of content - although I would agree that editing posts while on a 4 inch screen isn't ideal.  I'll compare my flow with the mobile version of the site.   On the mobile site, I can check my profile.   I can see my cumulative daily reputation score here. I can see my favorite questions here. I can see my most recent activity. I get credit for visiting the site.       In the app, I can check the feed.   I see new questions on sites that I'm definitely a member of, or that I've recently visited in the app. I'm not convinced I get credit for visiting the site on the mobile app.  Nor am I convinced that I should - although I want to.       On the mobile site, I can see what badges I've earned overall.   In the app, I can see what badges I've earned that day.       On the mobile site, I can order the results of questions with a lot of answers by votes.   On the app, that's not possible.    What I'm getting at is, despite it being an early alpha, it doesn't feel like it's going to have feature parity with the mobile desktop site.  So, is it meant to supersede the mobile desktop site?  Is it meant to be a CRUD application for SO?  Or does it fit somewhere in between?  I can provide better feedback and bug reports to the team if I have a clear understanding of what niche the app is trying to fill.


Suggestion for enforcing unique constraint in a table where soft delete is implemented

I am using SQL Server 2014 and in my database, I have a Position table which is structured like this:  ID         int           PK Name       nvarchar(50)  Unique Index IsDeleted  bit              A user can't enter positions with similar names; IsDeleted is a flag for soft delete as I want to avoid deleting records from this table. However it got me thinking in a scenario like this:  1. User enters position 'President'. 2. User deletes position 'President'.  3. User changes mind and again enters a position 'President'.    This would result in an error due to unique constraint. Even if I use Name and IsDeleted combination for unique constraint, there is no stopping the user from deleting again and adding several times. One thing I can think of is having Name and TimeStamp combination as unique constraint, but it doesn't sound correct.  I'd like to enforce this if possible in the database, and not the application logic. Can you guys give some suggestions?


Find the set of interstion of $ \ (\mathbb{Z}_p \setminus \mathbb{Z}) \cap \mathbb{Q}$ shwoing its elements

This question is from $\text{p-adic numbers}.$  My questions are-  $(1)$ Is the set $  \ (\mathbb{Z}_p \setminus \mathbb{Z}) \cap \mathbb{Q}$ non-empty?  If non-empty, then what are the elements or the intersection set?  $(2)$ Is the set  $ \ (\mathbb{Z}_p \setminus \mathbb{Z}) \cap \mathbb{Q}_p $ non-empty?  If non-empty what are the elements or the intersection set?  I can not conclude the answer.  Please someone help me with details answer or at least hints.


Finding YMin and YMax of polygons in shapefile using ArcPy?

I'm using ArcMap 10.  I want a python script that  tells me the Xmin, Xmax, Ymin, and Ymax of a polygon. (I guess this is finding the extent of a polygon?)  My current script gives me the correct the Xmin and Xmax, but it gives me the Ymin and Ymax of the data frame. I want the Ymin and Ymax of a polygon.  Here is my current code:  # Specify the shapefile shapeFile = "C:/Big_Creek_MapUnits.shp"  # Use the describe function desc = arcpy.Describe(shapeFile)  # Print stuff out arcpy.AddMessage(desc.extent.Xmin) arcpy.AddMessage(desc.extent.Xmax) arcpy.AddMessage(desc.extent.Ymin) arcpy.AddMessage(desc.extent.Ymax)   Anyone have any solutions or tips?


implement a special font and looking its name

I wish to write our manuscript by the font of this document:    We think it is legible and beautiful. However, we do not know what is the type of font (the name of that) to be implemented on our manuscript.   Does anyone have an experience for this font? Is anyone familiar with it?


Find the cardinality of the set $\{ X \subset \mathbb{N} : |X| = \aleph_0\}$

Find the cardinality of the set $\{ X \subset \mathbb{N} : |X| = \aleph_0\} $. First off all I could easily prove that the set given above, say $S$, is uncountable. Because $P(\mathbb{N})$ is uncountable and $|P(\mathbb{N})|=c$, and $P(\mathbb{N}) = S \cup F$, where $F$ = $ \{$family of all finite subsets of $\mathbb{N}$ $\}$. So, $S$ is countable $\implies$ $P(\mathbb{N})$ is countable as $F$ is clearly countable. Which is a contradiction. But I can't find the cardinality of $S$. Now, $$S \subset P(\mathbb{N})$$ $$\implies |S| \le |P(\mathbb{N})|=c$$ And, $$|S| \gt \aleph_0$$ Again, $$\aleph_0 \lt c$$ But in order to say, $$|S|=c$$ I have to use Continuum Hypothesis. But can I do that because I know it's a hypothesis and also with current mathematical tools it cannot be proved that this is false(I got to know this from internet)?


Morph a ball into another (Terminator T1000 style)?

Is there any way to achieve this effect: Where a ball intersects and "morphs" into another ball like  (Terminator T1000 style)...?  E.g: I have this blob that needs to morph into this wall, but the wall won't really change in thickness.    Thanks in advance.


Proving $ \sum _{k=0} ^m \binom nk \binom{n-k}{m-k} = 2^m \binom {n}{m}$.

Give an algebraic and a combinatorial proof for the following identity:       $$ \sum _{k=0} ^m \binom nk \binom{n-k}{m-k} = 2^m \binom {n}{m}.$$      For the combinatorial argument, use the analogy of $n$ party guests, where $m$ of them describe themselves as either vegetarian or vegan (but not both).   After proving the identity using algebraic transformations, I'm unable to find a combinatorial argument for it. For the right hand side, if we multiply $\binom nm $ by $2^n$, we get the Pascal-triangle but with each row multiplied by $2^n$, but here we're multiplying by $2^m$. What does this mean? How does the analogy with the party guests work? Any help would be much appreciated.


I have a file, from which I need to extract words between two patterns  e.g. i need to extract between originatingMessageId  For this input file  userGLN|originatingMessageId0028400000000~20170412194316~1182055~1/originatingMessageId/header|documentException|originatingDocumentId|0028400000000~20170412194316~1182055~1~15~19649/originatingDocumentId|link|operation|DELETE|operation||informationProviderGLN|0028400000000|informationProviderGLN|   the expected output file would be:  0028400000000~20170412194316~1182055~1


How I can change the object properties after I add it in the scene and move it?

Suppose I add torus in my scene, and I change in the Minor segments from 16 to 3. In addition, I made many actions such as scaling, rotating and moving the object. How I can return to the Minor segments to 16 after all these actions? I do not add any actions in the edit mode.


UK transit visa required post December 2014 changes in visa rules?

My Parents are travelling from India to Usa on Jan 20th, 2015. They have Indian passports & a valid US Visa(B1/B2). Travelling with British Airways & have 7 hours layover in Heathrow, London. A known person of us were recently not allowed to board BA flight from Bangalore, since they didn't had a UK transit visa. They were EAD holders. Any information in this regard is appreciated..


Struct is value type while it's derived from Object class - how it works in .Net framework

As we all know that everything in C# is derived from Object class.   Then why struct is value type and class is reference type? I mean struct (type) itself has derived from Object class (class type) then how we can say that struct is not a reference type?


ORIGINAL QUESTION:  When I try to mount an ISO file using:   Right click the file and select [Open With] > [Archive Mounter] Right click the file and select [Open With] > [Disk Image Mounter] [gnome-disk-utility] > [Disks] > [Attach Disk Image] sudo mount -o loop '/media/oshirowanen/250GB.iso' /media/iso   I get the following error message for attempts 1, 2, 3, and 4:  Unable to access “New Volume” Error mounting /dev/loop10p1 at /media/oshirowanen/New Volume: Command-line `mount -t "ntfs" -o "uhelper=udisks2,nodev,nosuid,uid=1000,gid=1000" "/dev/loop10p1" "/media/oshirowanen/New Volume"' exited with non-zero exit status 21: ntfs-3g-mount: mount failed: Permission denied Failed to sync device /dev/loop10p1: Input/output error Failed to close volume /dev/loop10p1: Input/output error   Anyone know how to resolve this?    UPDATE 1:   sudo mount -o ro,loop /media/oshirowanen/250GB.iso /media/iso   The following error is given for attempt 5:  mount: wrong fs type, bad option, bad superblock on /dev/loop12,        missing codepage or helper program, or other error         In some cases useful info is found in syslog - try        dmesg | tail or so.     Possible useful info  The iso was created from an ntfs drive using the command  sudo dd if=/dev/sde | pv | sudo dd if=/media/oshirowanen/250GB.iso


I'm not a Linux superuser. However I decided to install official JDK-9 so I done those steps:  wget --no-cookies --no-check-certificate --header "Cookie: oraclelicense=accept-securebackup-cookie" \ http://download.oracle.com/otn-pub/java/jdk/9+181/jdk-9_linux-x64_bin.tar.gz \ -O jdk-9_linux-x64_bin.tar.gz   Move to /opt/  sudo mv jdk-9_linux-x64_bin.tar.gz /opt/   unzip:  cd /opt/ sudo tar -xzf jdk-9_linux-x64_bin.tar.gz   update-alternatives:  sudo update-alternatives --install /usr/bin/java java /opt/jdk-9/bin/java 1000 sudo update-alternatives --install /usr/bin/javac javac /opt/jdk-9/bin/javac 1000 sudo update-alternatives --install /usr/bin/javadoc javadoc /opt/jdk-9/bin/javadoc 1000 sudo update-alternatives --install /usr/bin/javap javap /opt/jdk-9/bin/javap 1000  sudo update-alternatives  --config java   I choose [1]  0 /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java    [Auto] 1 /opt/jdk-9/bin/java                               [manual mode] 2 /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java    [manual mode]   After that I got this:  update-alternatives: using /opt/jdk-9/bin/java to provide /usr/bin/java (java) in manual mode   After all steps I still getting jdk 1.8.0 after using  java -version   So I edited /etc/environment/Now it's look like this:  PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games" export JAVA_HOME=/opt/jdk-9 export JAVA_HOME=/usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java export PATH="$PATH:$JAVA_HOME/bin"   And I also edit ~/.bashrc (when I install JDK-8 I added to end of file)  export JAVA_HOME='/usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java' PATH=$JAVA_HOME/bin:$PATH_HOME/jre/bin:$PATH   After logout I can't login. And of course I getting infinity loop login. I can fix something with ctrl+alt+F1 console but I don't know what... I think I spoiled something in /etc/environment or ~/.bashrc  Can someone help me fix this?


Why is the linker not complaining about multiple function definitions (only with templated functions)?

pid.h  #include <iostream>  template <class T> void f(T t);   pid.c  #include "pid.h"  template <class T> void f(T t) {   std::cout << t; }  template void f<int>(int);   pid2.c  #include "pid.h"  template <class T> void f(T t) {   std::cout << 55; }  template void f<int>(int);   main.c  #include "pid.h"  int main() {   f(1);   return 0; }   command:  g++ "-IC:\\Users\\kam\\workspace\\boost_1_56_0" -O0 -g3 -pg -Wall -c -fmessage-length=0 -std=c++11 -pthread -o "src\\pid2.o" "..\\src\\pid2.cpp"  g++ "-IC:\\Users\\kam\\workspace\\boost_1_56_0" -O0 -g3 -pg -Wall -c -fmessage-length=0 -std=c++11 -pthread -o "src\\pid.o" "..\\src\\pid.cpp"  g++ "-IC:\\Users\\kam\\workspace\\boost_1_56_0" -O0 -g3 -pg -Wall -c -fmessage-length=0 -std=c++11 -pthread -o "src\\main.o" "..\\src\\main.cpp"  g++ -pg -o Hello_World.exe "src\\pid2.o" "src\\pid.o" "src\\main.o"     result:  55   Now, if I make the functions in pid.c and pid2.c non-templated I do get the multiple definition error.


Find the density of the sum of two uniform random variables

Let $X$ and $Y$ be independent and uniform random variables on $(0,1)$. Find the density of $X+Y$.  I know $$f_{X+Y}=\int_{-\infty}^{\infty}\,f_X(x)\,f_Y(z-x)dx$$  Now when $x\in(0,1)$, I know $f_X(x)=1$. Assuming $z\in (0,1)$, I need $z>x$ in order for $f_Y(y)=1$. In that case, $$f_{X+Y}=\int_{0}^{z}\,(1)\,(1)dx=z.$$   Now when $x\in(0,1)$,  $f_Y(y)$ can also equal $1$ if $z \in (1,2)$. In that case, I need $z-x<1 \implies x>z-1.$ So I have: $$f_{X+Y}=\int_{z-1}^{1}\,(1)\,(1)dx=2-z.$$   Does this all look correct?


i have a loop checking the value of a variable and when i update the variable "i" to match one of the if statements nothing happens, anyone know why this is happening or how to fix it? i have it printing the "i" variable to console so i can see it changing but it wont activate one of the if statements   code  package window;  import java.awt.EventQueue;  import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.border.EmptyBorder; import javax.swing.JButton;  import java.awt.event.ActionListener; import java.awt.event.ActionEvent;  import javax.swing.JTextArea; import javax.swing.JTextField;  public class Gui extends JFrame {  public JPanel contentPane; public static JTextField input; public static JButton send; public static JTextArea console; public static JTextArea invintory; public static JTextArea stats;  /**  * Launch the application.  */    /**  * Create the frame.  */ public Gui() {     //variables      int Gold = 20;     int Health = 100;     int MaxHealth = 100;       //variables end     setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);     setBounds(100, 100, 450, 300);     contentPane = new JPanel();     contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));     setContentPane(contentPane);     contentPane.setLayout(null);      console = new JTextArea();     console.setEditable(false);     console.setBounds(10, 11, 281, 214);     contentPane.add(console);      input = new JTextField();     input.setBounds(10, 236, 281, 20);     contentPane.add(input);     input.setColumns(10);      stats = new JTextArea();     stats.setEditable(false);     stats.setBounds(301, 11, 123, 53);     contentPane.add(stats);      invintory = new JTextArea();     invintory.setEditable(false);     invintory.setBounds(301, 75, 128, 137);     contentPane.add(invintory);      send = new JButton("Send");        send.setBounds(301, 224, 128, 32);     contentPane.add(send);      stats.append("Health: " + Health + "/" + MaxHealth + "\n");     stats.append("Gold: " + Gold);      }  public static void game (JButton send, JTextArea console, JTextArea stats, JTextArea invintory, JTextField input) {      //variables      int Gold = 20;     int Health = 100;     int MaxHealth = 100;         //start     //START     //START     //START     //START     while (true) {           input.setText("");         String i = "";          send.addActionListener(new ActionListener() {                 public void actionPerformed(ActionEvent arg0) {                     String i = input.getText();                     System.out.println("input is " + i);                     stats.setText("");                     stats.append("Health: " + Health + "/" + MaxHealth + "\n");                     stats.append("Gold: " + Gold);                 }             });         console.append("You wake up open feild, with vast amounts of wheet in every direction\n");         console.append("There is a path going in either direction what do you want to do\n");         console.append("\t1. Go left.\n");         console.append("\t2. Go right.\n");          while (i == "") {         if (i == "1") {             console.append("1\n");             break;         }         else if (i == "2") {             console.append("2\n");             break;         }         else {          }         }        }     //END     //END     //END     //END     }  public static void main(String[] args) {             try {                 Gui frame = new Gui();                 frame.setVisible(true);                 Gui.game(send, console, stats, invintory, input);             } catch (Exception e) {                 e.printStackTrace();             }          } }


PHP preg_replace a pattern multiple times in the same string

I have a text string in which I'd like to replace a pattern that occurs multiple times with a tag, like this:  <?php $str = 'A *word* is a *word*, and this is another *word*.'; preg_replace('/\*([^$]+)\*/', '<b>$1</b>', $str); ?>   However, the function is replacing the whole range from the first asterisk to the last asterisk, i.e. it doesn't separately enclose each pattern with the tag, which is what I'm trying to accomplish.


Definite integral, quotient of logarithm and polynomial: $I(\lambda)=\int_0^{\infty}\frac{\ln ^2x}{x^2+\lambda x+\lambda ^2}\text{d}x$

I was thinking this integral : $$I(\lambda)=\int_0^{\infty}\frac{\ln ^2x}{x^2+\lambda x+\lambda ^2}\text{d}x$$ What I do is use a Reciprocal subsitution, easy to show that: $$I(\lambda)=\int_0^{\infty}\frac{\ln ^2x}{\lambda ^2x^2+\lambda x+1}\text{d}x =\frac{1}{\lambda}\int_0^{\infty}\frac{(\ln x-\ln \lambda)^2}{x^2+x+1}\text{d}x \\ =\frac{\ln ^2\lambda}{\lambda}\int_0^{\infty}\frac{1}{x^2+x+1}\text{d}x+\frac{1}{\lambda}\int_0^{\infty}\frac{\ln ^2x}{x^2+x+1}\text{d}x \\ =\frac{\ln ^2\lambda}{\lambda}\frac{2\pi}{3\sqrt{3}}+\frac{2}{\lambda}\int_0^1\frac{\ln ^2x}{x^2+x+1}\text{d}x$$ But I hav no idea on process the remaining integral:( Anyone knows how to solve it?  THX guys! I came with another method might work for this: Recall the handy GF $$\frac{1}{x^2+x+1}=\frac{2}{\sqrt{3}}\sum_{k=0}^{\infty}\sin \left(\frac{2\pi}{3}\left(k+1\right)\right)x^k$$ Then we have :  $$\int_0^1\frac{\ln ^2x}{x^2+x+1}\text{d}x=\frac{2}{\sqrt{3}}\sum_{k=0}^{\infty}\frac{2}{\left(k+1\right)^3}\sin \left(\frac{2\pi}{3}\left(k+1\right)\right)x^k$$ With $$\sum_{k=1}^{\infty}\frac{\sin (kx)}{k^3}=\frac{\pi ^2}{6}x-\frac{\pi}{4}x^2+\frac{x^3}{12}$$ What can we arrived?


Using Member Type from Template Parameter

I'm interested in doing some thing like this.  template<typename Clock> struct A {     Clock::time_point time; }  A<chrono::steady_clock> a;   However this is not possible. How can I achieve this?   I think there maybe away around using this method in Clock's context but what is the proper way to do this in general?


How to find the Lihzahrd temple in Terraria?

I have been looking all over my jungle in Terraria and I can't seem to find the Lihzahrd temple anywhere. Does anyone have any tips on how to find it?


Exporting Graphic with transparency in layout to PDF using ArcGIS for Desktop?

I'm using ArcGIS 10.1 for Desktop.  I am trying to export a pretty simple map to PDF and finding the results are not what I expect. I have inserted two graphics on top in Layout. One is just a rectangle that has a custom user style applied. The style uses a Picture Fill derived from a PNG file that has transparency set to 80% opacity in the original file.  The other graphic is a rectangle text box that has a similar Picture Fill Style applied, this one using a 20% grey fill and 80% opacity in the original PNG file. On screen, the boxes look fine. That is, I can see other layer information underneath that looks greyed out with a partially transparent box overlaying.  When I export to PDF, the boxes show up as empty of any fill at all. The sample text in the text box shows up, but not the transparency fill.  Resolution is set to 300 DPI, Resampling is set to best. Colour space is set to CMYK. There is no compression. Bitmap fills are set to vectorize. I have tried varying every setting that can be changed in Export to PDF and find that nothing really changes with regard to this transparency issue.  Any ideas? I have scanned other forum posts and see that it is an issue from several versions back. Has it ever been solved?


"An (obvious) problem" or "a (obvious) problem"?

Suppose I want to add a qualifier to a noun that isn't necessary for understanding, so I decide to put it in parentheses. If the adjective in parentheses would change whether I use "a" or "an" as an article, which one is correct?  For example, as in the title, I want to mention that a problem is obvious. Without the qualifier it would be "a problem", with it "an obvious problem". Would it be "an (obvious) problem" or "a (obvious) problem"?  I suspect the first one to be correct, but is that true? My understanding of parentheses is that the sentence should make sense with or without the part between them, but in this case one option sounds weird when including it and one sounds strange when leaving it out.  Edit: Please note that this is not a duplicate of  . There, the question is about an adjective directly following the article without any parentheses. I'm asking whether the special case with parentheses changes anything. Also, this is basically a nitpicking question: I know how to rephrase the expression to avoid the issue, but I want to know what is correct.


How do I test for a mob, with a given name, in a certain location?

I want to testfor a sheep, by the name of Lamb, in a certain location using coordinates.  I have already tried this:  testfor @e[x=999,y=80,z=-1034,type=Sheep,name=Lamb]   But it doesn't work. I have also tried:  testfor @e[x=999,y=80,z=-1034,type=Sheep]   But it says it found a sheep whether or not there is actually a sheep in that location.


How to filter any part of description or option from manpage

I want to get output of any desired description or option from a man page.  Example: I want to get the description for the autoclean option from the apt-get man page:  Please suggest a command, something like man apt-get | <somecommands> autoclean to get this output:   autoclean            Like clean, autoclean clears out the local repository of retrieved package files. The difference is that it only removes package files that can no longer be downloaded, and are            largely useless. This allows a cache to be maintained over a long period without it growing out of control. The configuration option APT::Clean-Installed will prevent installed            packages from being erased if it is set to off.   I've tried man apt-get | grep autoclean but it is limited to out-put matching lines for word autoclean so I can't get full description and seems it is not that what I want!  Hence, Help me to filter part from man-page for expected output mentioned above.   (Here apt-get and autoclean is only used as example I am asking this question because when man-page is too long then filtering by such way is very helpful for getting exact thing)


How can I set up multiseat/separate X sessions with gnome 3?

With classic Gnome, if one had two monitors, one could set up "separate X sessions" for each monitor.  In this configuration, each monitor had a separate user login session and application windows were captive to the X session they were launched from.  Is something similar possible with Gnome 3?  If so, how do you go about setting it up?


I understand that in regular fusion, you use high levels of heat to accelerate atoms to speeds high enough to overcome nuclear force.  What method would be used to achieve ?


After a question get closed, it can be reopened after it was substantially enhanced.   But it may be substantially enhanced while it has one or more close votes, but not closed yet.  I think it should be possible to get the close votes removed in case there is a majority that it should be reopened if it were closed. Some close votes mean a question is only partially closed. Now, few or just one vote could close it. I think partly closing should be reverted if it would be voted to reopen when completely closed.   Is this possible? If not, is it a helpful feature?


Technologies that allow YouTube scale distribution?

Youtube as we know, is massive. It has thousand of concurrent users streaming at least 2 megabytes per video. Obviously, that gets to be a lot of traffic... far too much for any one server.  What networking technologies allow pushing


TP player in 1.15.2 relative to the player, not the command block

It says it all in the title. Anything I try (using /teleport, using /execute) teleports the player relative the command block. I just want the player to teleport to y=46 when I power a command block. Thank you for your help.


Why does the verb "be" have so many forms?

I am. You/we/they are. He is. I/he was. You/we/they were. I had been. ... to be. ... being bad. ...   Why are there so many forms for this verb, and why are they so dissimilar? If you go far enough back, was there a time where they were more similar? Did a couple of languages merge in the verb to be?


how do I check that french-babel is loaded?

(1) What argument <arg> do I supply to \ltx@ifpackageloaded{<arg>} to specifically catch french babel? (2) Would you mind compiling the MWE with \usepackage{siunitx} commented out. If it produces compiler error ! Undefined control sequence.<argument> \text{loaded} ...eLoaded[babel]+: \myIsPackageLoaded[babel] as it does for me, I would like to know why?!     \documentclass{minimal} %RN. 10Aug16. MWE_17_04 \usepackage{ltxcmds} \usepackage[frenchb,english]{babel} %\usepackage{siunitx} \usepackage{MyUtilities} \begin{document} \verb+\myIsPackageLoaded[babel]+: \myIsPackageLoaded[babel]  \verb+\myIsPackageLoaded[frenchb]+: \myIsPackageLoaded[frenchb]  \verb+\myIsPackageLoaded[french-babel]+: \myIsPackageLoaded[french-babel]      \end{document}  \ProvidesPackage{MyUtilities} %\usepackage{expl3} \usepackage{xparse} \ExplSyntaxOn \NewDocumentCommand\myIsPackageLoaded{O{}}{\myIsPackageLoaded_Main:nn {#1}}  \cs_new:Npn \myIsPackageLoaded_Main:nn #1   {     \ltx@ifpackageloaded{#1}{\text{loaded}}{\text{not~loaded}}   } \ExplSyntaxOff


How this mechanism of value assignment work?

I am a beginner in coding C++. I came across this piece of code. I couldn't understand why the variable 'a' gets assigned value 5 and variable 'b' gets assigned the value 1.  #include <iostream> using namespace std;  int main () {     int a, b;     a = 5, 2, 3;     b = (5, 2, 1);      cout << a<<endl;     cout << b <<endl;     cout << a + b;     return 0; }   The value of   'a' is 5, 'b' is 1. But how?


Please allow a user to sort the experiences on the career site

Just joined Stack Overflow careers and figured I'd chime in and ask for a feature. It appears that the order you insert the "Experience" items in is how they stay. I seem to have put mine in ascending order instead of the more traditional descending. It would be helpful if SO Careers had a sort feature for that section. I certainly want potential employers to see my latest experience first.


Is a duplicate in two societies, a duplicate?

Peace be upon you,  Suppose that you have a question which is completely suitable for two societies (e.g. a research-level math question which can be posted to both of math.SE and mathoverflow). Is it considered duplicate if you post in both societies?  If yes, why should you deprive your question to be reviewed by the users of one society? it can be of great benefit to use the opinions of two society users.  If the answer is no, please just tell me and if yes, I suggest that it would be allowed to post such questions but with a duplicate label, beside.


I want to use \itemize{} in a table. Here is a fairly simple set up (itemize{} taken from here: )  \documentclass{scrartcl} \usepackage[ngerman]{babel} \usepackage[T1]{fontenc} \usepackage{lmodern} \usepackage{blindtext}   \begin{document} \begin{table}[] \centering \caption{My caption} \label{my-label} \begin{tabular}{lll}  &  &  \\  & \begin{tabular}[c]{@{}l@{}}\begin{itemize}\\ \item Erstes Element,\begin{itemize},\item Nächste Ebene,\item Item in 2. Ebene,\end{itemize}\\ \item Zweites Element\\ \item Drittes Element,\begin{itemize},\item Die zweite Ebene,\begin{itemize},\item Die dritte Ebene,\item Item in 3 Ebene,\end{itemize},\item Item in 2. Ebene,\item Item in 2. Ebene,\end{itemize}\\ \item Viertes Element\\ \item Fünftes Element\\ \end{itemize}\end{tabular} &  \\  &  &  \end{tabular} \end{table} \end{document}   That does not compile. However, when I include the \itemize{} list "raw", not in a table  \documentclass{scrartcl} \usepackage[ngerman]{babel} \usepackage[T1]{fontenc} \usepackage{lmodern} \usepackage{blindtext}  \begin{document} \begin{itemize} \item Erstes Element     \begin{itemize}         \item Nächste Ebene         \item Item in 2. Ebene     \end{itemize} \item Zweites Element \item Drittes Element     \begin{itemize}         \item Die zweite Ebene             \begin{itemize}                 \item Die dritte Ebene                 \item Item in 3 Ebene             \end{itemize}         \item Item in 2. Ebene         \item Item in 2. Ebene     \end{itemize} \item Viertes Element \item Fünftes Element \end{itemize}  \end{document}   It works. Why?


Why we cannot write something like that:  Func<int, int> operation = i == 1      ? (int a, int b) => a + b      : (int a, int b) => a * b;      Type of conditional expression cannot be determined because there is no implicit conversion between 'lambda expression' and 'lambda expression'


clarification asked for 'difference between convolution and crosscorrelation?'

I don't understand answer formulated in ways like this "Thus, $p\ast q$ is the distribution of $X+Y$. The cross-correlation $p\circ q$ is the distribution $c=(c_n)_n$ defined by $c_n=\sum\limits_kp_kq_{n+k}=P[Y-X=n]$ for every $n$. Thus, $p\circ q$ is the distribution of $Y-X$."  Can someone explain this in an easier way? See:   PS: By convolution I meant the type of convolution that is used in image and signal processing. Stuff like this:


My edit to an answer was accepted by two of the three reviewers, with the third rejecting with a claim that part of my edit was incorrect.  In fact, my proposed edit was entirely and demonstrably correct, and the reason given for rejecting is invalid.  How can I let that reviewer know about their error, and have them change their review to "Accept" - changing stats for both of us?  Please note:  This is not the same question as asking for an appeal of an edit that was rejected.  It's asking what I can do about one of the three reviewers, a dissenter who voted against my edit based on their incorrect information.


I have a problem with SQL code in a PDF document. For code representation I'm using the listings package. Everything works perfect until I copy-paste that code from the created PDF document. I get some phantom spaces in string type. When people are reading my PDF document, they need to copy-paste some of the code. Visually the code looks good in PDF, but when I try to copy-paste my code to NotePad or any other editor I get some unexpected spaces in strings. In the example below, when I copy-paste my SQL code, instead of getting:  SELECT ST_Area(the_geom)   FROM katastar   WHERE kc_broj = '1414';   I get  SELECT ST_Area(the_geom)   FROM katastar   WHERE kc_broj = ' 1414 ';   See the spaces in between quotes.  \documentclass{article} \usepackage{listings,xcolor}  \lstset{  tabsize=4,         basicstyle=\scriptsize,         %upquote=false,         aboveskip=\baselineskip,         columns=fixed,         showstringspaces=false,         extendedchars=true,         breaklines=true,         prebreak = \raisebox{0ex}[0ex][0ex]{\ensuremath{\hookleftarrow}},  frame=single,         showtabs=false,         showspaces=false,         identifierstyle=\ttfamily,         keywordstyle=\color[rgb]{0,0,1},         commentstyle=\color[rgb]{0.133,0.545,0.133},         stringstyle=\color[rgb]{0.627,0.126,0.941},  language=SQL }  \begin{document} \begin{lstlisting} SELECT ST_Area(the_geom)   FROM katastar   WHERE kc_broj = '1414'; \end{lstlisting} \end{document}


What is the difference between known variables and unknown variables?

Also, From Wikipedia     When writing polynomials, the coefficients are usually taken to be known and the indeterminates to be unknown, but depending on the problem, all variables may assume either role.   Isn't it is the case that coefficients are constants and not variable? What it is referring towards by 'inderminates'-variable?  Is it related to dependent variable and independent variable?


How to change sql database name using sql query?

please give sql query to change or rename the sql database name


Are there English figurative expressions equivalent to Japanese idiom 馬耳東風 meaning a person who doesn’t listen to other’s advice?

North wind tells the arrival of spring season in Japan. And incidentally, we  have an idiom, “馬耳東風,” of which literal translation is ‘the east wind to the ears of horse,’ meaning a person who doesn’t listen to, or respect other’s opinion, advice, and suggestion like a horse is insensitive to the meaning and tastefulness of east wind.  For example, we say “His boss’s admonition was just an east wind to Taro. And he was fired.”   I don’t know why it should be east wind, not west, south or north wind, but Chines have the same saying, “东风吹马耳.”  The structure of “East wind to a horse” resembles “Pearls to a swine,” but is pretty different in meaning.   Are there similar figurative expressions to describe a person who has deaf ears to others' advice and opinion, like an obstinate or insensitive horse?


A few days ago I did some summer cleaning on my computer, moving a bunch of old files to an external Flash drive for backup and then deleting them from the computer. To make sure that no one could recover my old photos or videos, I used this program called Eraser to wipe the free space after I moved the files. I used the Guttman method (35 passes) to wipe the free space on my hard drive.   Is there any way someone could recover this data even after I wiped it with 35 passes? Let's say I sold my hard drive on Amazon and someone bought it. Would they be able to do it?


Given is prime number $p$ and natural number $a$ which is relatively prime to $p$. Prove that no numbers from the set $B={0a,1a,2a,...,(p-1)a}$ give the same value after divison by $p$.


Firefox opens downloaded PDFs in File Roller

When I download a PDF and try to open it from the Downloads window, it will attempt to open it in File Roller, which will complain that about PDF not being a supported archive type; I'd like to open it in Document Viewer instead. How do I do that from Firefox, other than going through Nautilus?  When opening the PDF from Nautilus, it opens the file correctly in Document viewer. I also went in about:preferences#applications and set Use Document Viewer (default) as the action for PDFs, but it didn't work.


OK, win 7 is done, so I upgraded to win 10 on my HP6644Y desktop, (have win 10 on a laptop and am satisfied). After reading here about linux distro's I decided to try Ubuntu. downloaded it and supposedly set it up to dual boot with win 10. Computer booted into a ubuntu menu with choices for win 10, ok, I guess I can live with that. Decided I was not impressed with the ubuntu so I attempted to remove it. It would then only boot to a grub screen. Finally got the ubuntu restored. Now I want to restore or replace the win 10. My question is how do I do it?


How do I migrate from RHEL 5 to CentOS 5?

I've found myself in charge of installing some software on an old server running RHEL 5. Unfortunately, since it's just a development server now, it no longer rates a license. I'd like to continue using yum for dependency resolution, etc. My first thought was to just point yum at some CentOS repos, but some googling turned up this instead: . Is this sort of approach my best bet? If so, how much of the migration process is different for my scenario compared to the one in those instructions?


How do I perform a redirect to a custom URL after login?

I am trying to redirect users to a custom URL after they logged in, but my code doesn't work.  How do I redirect users after they logged in?


My girlfriend is starting a new business which is not yet ready for the public (opening soon) but I'm already taking care of putting it on Google Maps and Google Search. The business is named Peace of Cake Studio and it's already on Maps and Search if you search for it. The website is not yet available and won't show up on search results. However, Google shows the following when searching for Peace of Cake Studio:  Including results for piece of cake studio Search only for peace of cake studio  I know this is a common typo and owners of business with piece in the name will optimize for the peace typo. But is there anyway to optimize this on our side?


Wife has been using iPhoto/Photos and iMovie for storing family photos and videos for roughly 5 years. Have about a 300 GB iMovie library and 100 GB iPhoto library.  MacBook Pro is getting full (less than 10 GB free) which is obviously beginning to effect performance. Have always used a NAS for Time Machine to back-up but not doing anything offsite.   Not sure what to do to move these libraries or archive them to a) an external HD or b) an offsite storage. Is it possible to just "close" the library and move it to an external HD for archiving. From what I understand in iPhoto/iMovie, if you wanted to access that library later you could simply load that library.   Is there any how-to on this or a better method? Also moving forward should I be keeping the libraries on an external an just accessing them with Photos/iMovie?


Unable to locate package for peerguardian

I wanted to install PeerGuardian in Kubuntu 17.10.1. I followed .  The commands were:  sudo add-apt-repository ppa:jre-phoenix/ppa sudo apt-get update sudo apt-get install pgld pglcmd pglgui   Tried that and got this error message:  Reading package lists... Done Building dependency tree        Reading state information... Done E: Unable to locate package pgld E: Unable to locate package pglcmd E: Unable to locate package pglgui   Then I read somewhere that it was:  sudo apt-get install pgl   But I got this error:  Reading package lists... Done Building dependency tree        Reading state information... Done E: Unable to locate package pgl   I heard that I need something called arm which is not x86 or amd64 but I am not sure.


Rudin's proof on the Analytic Incompleteness of Rationals

In Rudin's classical "Principles of Mathematical Analysis," he gave a proof like this:  Claim: Let $A= \{p\in \mathbb{Q} | p>0, p^2 <2\}$. Then A contains no largest number. Proof: Given any $p\in A$. Let $q = p-\frac{p^2 -2}{p+2}$.  Later Rudin claimed that $q^2<2,$ and $q>p$. My instructor asks us to think about a question on our own: Why is such $q$ a natural choice in this proof? I can see that in this way, $q>p$ is for sure. However, how does it become a natural choice?


Please let us know how can I find out unused and duplicate indexes from SQL servers, I searched in Google but there is no good information.


Is a function whose derivative vanishes at rationals constant?

I'm trying to make a problem for my advanced calculus students.  I was thinking, if we have a differentiable function $f:\mathbb{R}\to\mathbb{R}$ such that $f'(q)=0$ for all $q\in\mathbb{Q}$, can we say that $f$ is constant?


How can I find angles between the edges in a face, and then make a loop for all faces in an object. I know I can set it up in a blender and just read it, but I'd like to send these angles to a text file. How to do it with Python


Suppose $M$ is a smooth manifold and $U$ is an open neighborhood of $p\in M$, let $\{X_1,\ldots,X_n\}$ be vector fields defined in $U$ such that for every $q\in U$ the set $\{(X_1)_q,\ldots, (X_n)_q \}$ is a basis for $T_qM$. I want to find out under what conditions is it possible to find a chart $(V,\phi)$ around $p$ such that $V\subset U$ and $$(*)\quad (X_i)_q=\frac{\partial}{\partial\phi^i}\Bigr|_q\quad \text{ for } i=1,\ldots,n\quad \text{ and every }q\in V$$ Here is my attempt of the situation. Let $(W,\psi)$ be some chart around $p$, now we can write $X_i$ in componentsas $$X_i=\sum_j X_i^j\frac{\partial}{\partial\psi^j}$$ We want a map $\phi:W\to \mathbb{R}^n$ that satisfies $(*)$ in its coordinates, the coordinates $(X_i'^j)$ are given by the chain rule as $$(X_i'^j)=\sum_k\frac{\partial \phi^j}{\partial \psi^k}X_i^k $$ We thus would need that $$\frac{\partial \phi^j}{\partial \psi^k}=\frac{1}{(X_i^j)}\delta_k^j$$ Hence, the obvious problem is that $X_i^j$ may be zero, how could one circumvent this? Is what I am trying to do even possible?


How to report if I found someone created a invalid tag?

I just found someone created a new tag. But I am sure the created tag is not valid. It has a typo. If the typo is fixed then the tag is already exist. How can I report to fix this?


How to Make Theorems and Equations Share Numbering

How do I make theorems and equations share numbering? The default numbering system goes like this:     Theorem 1. Blah blah blah...      1=0+1 (1)      Theorem 2. More blahs...      Theorem 3. No more blahs...      2=1+1 (2)   The numbers in the parenthesis are equation numbers. How do you change the above into this:     Theorem 1. Blah blah blah...      1=0+1 (2)      Theorem 3. More blahs...      Theorem 4. No more blahs...      2=1+1 (5)   I am using ntheorem package, but couldn't figure out how. Would I need to use a different package?


Figure to Fig in both Caption and Autoref

I need to change the caption Figure to Fig. for a journal. I am currently using:   \usepackage[font=small,labelsep=period]{caption} and  %Caption display style \captionsetup{figurename=Fig.,tablename=Table}   to rename the caption. The \autoref however, is still showing a Figure 1 instead of Fig. 1. Can someone tell me the alternative to the code \addto\extrasngerman{\renewcommand\figureautorefname{Abb.}} used in , applicable for Caption package.


I need the ia32-libs packages because Petalinux SDK requires it.  I have just updated to Ubuntu 15.10 today, and now it won't let me install this package. I've installed it before on Ubuntu 15.04, so there should be no reason why it won't install on 15.10, right?  I've added the correct file to the sources.list.d directory.      ┌─[♨ steven ♨ ][~]      └─(20:38)(pts/2) Prometheus ─╼ cat /etc/apt/sources.list.d/ia32-libs-raring.list deb http://old-releases.ubuntu.com/ubuntu/ raring main restricted universe multiverse   I did an update and tried to install the package, but this is all that happens...      ┌─[♨ steven ♨ ][~]      └─(20:41)(pts/2) Prometheus ─╼ sudo apt-get install ia32-libs Reading package lists... Done Building dependency tree        Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies:  ia32-libs : Depends: ia32-libs-multiarch E: Unable to correct problems, you have held broken packages.     ┌─[♨ steven ♨ ][~]      └─:( (20:42)(pts/2) Prometheus ─╼ sudo apt-get install ia32-libs-multiarch Reading package lists... Done Building dependency tree        Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies:  ia32-libs-multiarch:i386 : Depends: bluez-alsa:i386 but it is not going to be installed E: Unable to correct problems, you have held broken packages.   However when I try to install the bluez-alsa:i386 package, it tells me it needs bluez:i386. When I try to install that one, it tells me I need bluez-alsa:i386 ... if I try to install both, it tells me they conflict with each other...  Is something broken that I am not seeing? Is support for this ia32-lib package completely gone?   Do I just need to downgrade back to 15.04?  I am running 15.10 64-bit


I have this document:  \documentclass[paper=a4, fontsize=12pt]{scrartcl} \usepackage[utf8]{inputenc} \usepackage{csquotes} \usepackage[german]{babel} \usepackage{lmodern}  \usepackage{tocloft} \usepackage{graphicx} \usepackage{amsmath,amssymb,amstext} \usepackage[locale=DE]{siunitx}     \begin{document}         \section{Mobilfunk - Was ist das?}         \section{Kabellose \"Ubertragungsmethoden}         \section{Bedeutung des Mobilfunks}         \subsection{Gesundheitliche Faktoren}         \section{Empfang und Abschirmung}         \subsection{Feldst\"arkeunterschiede im Raum}         \subsection{Beeinflussung der Feldst\"arke durch Umgebungsbedingungen}         \section{Mobilfunknetze}         \subsection{\"Offentliche und nicht-\"offentliche Mobilfunknetze}         \subsection{SIM-Karten}         \section{Visionen} \tableofcontents \end{document}   and returns that:    How can I remove the red framed header ("Inhaltsverzeichnis")?


I'm sure I'm missing something very basic, but I can't see what it is.  The following is an excerpt from a larger program that deals hands of cards and determines their rank in poker.  This function turns the first letter in a card string into an integer so that it can be compared.  So, "king of spades" would  send the "k" to this function and it should return 13, "6 of hearts" sends the "6" and gets back 6, etc.  It considers a, k, q, j, and 1 as special cases and then uses Integer.parseInt() on all other inputs.  But, for some reason, it is not ever evaluating the special cases, it is running the else statement every time and crashing on parseInt() when it gets a letter.  All help is appreciated, thank you.      package testSpace;   import java.util.Scanner;   public class main {   public static void main(String[] args) {     Scanner sc=new Scanner(System.in);          System.out.println("Enter a single digit or an a, k, q, or j");         String thisRank = sc.next();        System.out.print(parseRank(thisRank)); }              public static int parseRank(String thisRank){         if(thisRank=="a"){             return 14;         }         else if(thisRank=="j"){             return 11;         }         else if(thisRank=="q"){             return 12;         }         else if(thisRank=="k"){             return 13;         }         else if(thisRank=="1"){             return 10;         }         else{             return Integer.parseInt(thisRank);         }        }      }


Mikrotik: Add HTTP Header Parameter to Requests

I want to add a parameter of MikroTik to all HTTP header requests using MikroTik. So all client and servers that connected to the MikroTik can trace the parameter in their HTTP header.  How can I achive this?


Someone stole my iPad and I got it back. Now the device is requesting for activation using @icloud.com address which I can't remember setting up.  Though I still have my Apple ID login details but can't use it to log in. I tried using my Apple ID, but it didn't work, I logged into , but could not see the @icloud.com address. I requested Apple for my data, but still couldn't find the @icloud.com address.  How do I resolve this issue?


Accidently upgraded from iOS 13.2 to latest iOS 14, how to revert?

iPhone popped the new update ready to install screen and I accidently hit install instead of later as I always do. It's now in the process of installing. How may I revert back to previous 13.2 once installation is complete?


Why are surds put on the numerator in the final answer when it is a fraction.

I have learnt that a fraction with a surd in its most simplest form should have the surd in the numerator and not the denominator? Why is it convention not to leave the surd on the denominator? Is it just arbitrary convention or does it have an actual purpose?


We want to integrate a light sensor driver with Ubuntu's kernel. Please advise how can we do it.   The light sensor code given .


Can some metadata about deleted posts be included in Data.SE?

I like to use  to view usage stats for some of the sites, however deleted posts are not included on Data.SE and I think this skews the numbers quite a bit, particularly on sites with a lot of deletions. Would it be possible to include some limited data about deleted posts in Data.SE to make statistical queries more accurate? You could clear the non-public data fields of deleted posts, such as Posts.Title, Posts.Body, and Posts.OwnerUserId to address privacy concerns explained . You could even leave the PostId set to 0 since I know SE doesn't want to provide users with a way of searching deleted questions. The data I would mostly be interested in is CreationDate, LastActivityDate, PostHistory (date closed, date reopened, date deleted, etc), and the fact there was a deleted question in the first place. Up/Down votes, Score, Tags, and View/Answer/Favorite count would also be preferred. This would make the statistical queries accurate, while still removing the information not meant to be visible to the public.


Create a Bootable Windows Flash Drive in Ubuntu

Is it possible for me to take a windows iso, and create a bootable USB stick while in ubuntu? There are loads of ways to do that on windows, but not from any linux-based os. Any information helps! Thanks.  EDIT: The version of windows can be wither windows 7, 8.1, or 10


Possible to determine the encryption key that was used by knowing the input and output of the encryption mechanism?

Assume that a malicious user knows what string is being encrypted (a user_id, for example, which the user can know) and can also see the result of the encryption (the encrypted user_id that is used to authenticate them to another site.)  If the user knows what is going into the encrypt function, as well as what is coming out, in theory it seems it could be possible for them to determine the encryption key as well.  Assuming that this is the case, what could be done to address this problem?  Background: The project I'm working on uses the code found below. I have concerns that the shared encryption key could become compromised   The concern is simple: The key is shared, so if someone knows the key, they can trick the authentication mechanism and log in with whatever user ID they want.


Loops as maps from $S^1\to X$, Hatcher 1.15

I am working on Hatcher's problem 1.1.5.  Show that for a space $X$, the following three conditions are equivalent.   $\textit{a)}$ Every map $S^1\to X$ is homotopic to a constant map.  $\textit{b})$ Every map $S^1\to X$ extends to a map $D^2\to X$  $\textit {c})$ $\pi_1(X,x_0)=0$.  I have shown that $a$ implies $b$.   Now I want to prove that $b$ implies $c$. Therefore, I let $[f]\in\pi_1(X,x_0)$. Then, $f:I\to X$ with $f(0)=f(1)=x_0$. I want to show that $f$ is homotopic to the constant path. Since $S^1\cong I/_{0\sim 1}$, $f$ induces a map $f':S^1\to X$ with $f'(1)=x_0$. By $b$, this map can be extended to a map $\tilde{f'}:D^2\to X$. Since $D^2$ is convex, $D^2$ is contractible, there exists a homotopy $\tilde{H}:I\times D^2\to X$, $\tilde{H}_0=const_{x_0}$, $\tilde{H}_1=Id_{D^2}$. I don't know how I can go on from this, There is also a point where I have to transfer back to $f$ without $'$.  For $c$ implies $a$: Let $[f]\in\pi_1(X,x_0)$. Then $f:I\to X$ is homotopic to the constant path $const_{x_0}$. Also here, I don't know how to go on.


How can I build a formula to include wildcard characters in VBA

I've been working on an Excel macro to calculate performance metrics, based on data obtained from TFS integration. I've come to a point where I'm trying to count ocurrences of some events. Based on my parameters, sometimes it's as easy as count when some specific text is found, but sometimes I'd have to count when the cells contains some text string.  So far, I know I could use the COUNTIFS formula by building it on code and then assign this to any cell. I'm getting error when, while building the formula string, I try to get the string that contains the text. I have a condition to assign this value, as follows:  If rowNumber = x Then     myString = "Found text" ElseIf rowNumber = y Then     myString = "*contained*" End If  formula = "=SUM(COUNTIFS(Range1, Condition1, Range2, " & myString If moreParameters Then     formula = formula & ",Range3, Condition3))" Else     formula = formula & "))" End If  Cells(i,j).Select ActiveCell.FormulaR1C1 = formula   So, when the specific text is found (case rowNumber = x), it works fine, but when I try to use the wildcard, it doesn't understand the quotes as part of the string. I tried with double quotes:  ElseIf rowNumber = y Then     myString = ""*contained*"" End If   But then it throws compile error (Expected: end of statement), and with CHR(34) as well, without success. How come I could include the expression to use the wildcards in the formula string to use later?


How can I use hyper reference command in Latex?

In LaTeX, I want to refer any article by using \cite{name} successfully. Now I want to cite the same article in my paper and also the citation is hyperlink with the original document. I tried with command \hyperref{} but not successful. Can anyone plz tell me to do so? Thanks.


If A+tB is nilpotent for n+1 distinct values of t, then A and B are nilpotent.

Suppose $A$ and $B$ are $n\times n$ matrices over $\mathbb{R}$ such that for $n+1$ distinct $t \in \mathbb{R}$, the matrix $A+tB$ is nilpotent. Prove that $A$ and $B$ are nilpotent.     What I've tried so far:  Define $f(t)=(A+tB)^n$. Then $f(t)$ has polynomials of degree at most n as its entries. Each of these polynomials has n+1 distinct roots, and hence is the constant zero polynomial. This shows that for all $t \in \mathbb{R} \ f(t)=0$, which in particular gives $A^n= f(0) =0$ that shows A is nilpotent. Now if none of the $t_1,...t_{n+1}$ , that make A+tB nilpotent, is zero, we can use $g(t)=(tA+B)^n$ with roots $\frac{1}{t_i}$ similarly and show that B, too, is nilpotent. But I have no idea in case one of the $t_i$ is zero.  Thanks in advance.


We're working on a Log Viewer. The use will have the option to filter by user, severity, etc. In the Sql days I'd add to the query string, but I want to do it with Linq. How can I conditionally add where-clauses?


Diplomacy Attacking a Territory as they move

If I convince Turkey, to move Army Bul to Gre, would I be able to send Army Ser to Bul and take the area?


Why can't I type simple formulas when using transforms?

what its happening here? i just want to rotate R 360/5 but if do that the math function turns in to something like R [1/(360)]  even more if i divide by one i get 3282.81º    if i want to do a simple math i need to do  R ** <backspace> 360/5 and that way works, but versions ago I only need to type R 360/5 and that was it.  I remember something about this change months ago but i really don't understand it and also didn't find anything at the reference.       Rotation   To specify a value for clockwise rotation, press R, (0 - 9), then Return to confirm. To specify counter-clockwise rotation press R, Minus, (kbd:0 - 9), then Return to confirm. Note that 270 degrees of clockwise rotation is equivalent to -90 degrees of counter-clockwise rotation.       source:


Abrupt changes in direction and loss of energy

In the picture that I drew above, I was thinking that there is definitely loss of energy when the ball rotates off of the inclined plane to the small section of horizontal plane. However, I do not know the mathematical equation to model the theoretical change in velocity. Is there a definite relation between the angle of incline and how much energy is lost?   I was thinking that the velocity at the horizontal section is $v\cos\phi$, where $v$ is the speed of ball at the bottom of the ramp while still on the ramp, and $\phi$ is the angle of incline. However after doing experiments on it, this relation seems not to hold as my final values in the experiment is larger than even the value in theory.  If this relation is correct, how can the result of my experiment be explained?


How to slice an area in rectangles optimally?

Given a contiguous subset of a chessboard (or, more general, a 2d rectangular grid), how can I algorithmically determine a minimal set of rectangles covering the area?    In this example, the "contiguous subset" is the black area, and I am interested in the three red rectangles. There should be no overlap between the rectangles. The relative sizes of the rectangles is not too important; it would be a bonus if the sizes weren't too different.


I cannot easily figure out which one is more appropriate to use:     It's important to me.        It's important for me.   Are they the same? If not, what's the difference?


Users need to login using External Authentication Provider

I have a requirement where users need to log in to salesforce using external authentication provider. The configuration in Open-id authentication. I have created the connection in Auth.Providers along with all the required key, id, url and tokens. Salesforce has automatically created a registration handler. Using Test-Only Initialization URL, I have tested the connection and I have recieved the XML which states that the connection is working fine  Now, I need the users to log in using that provider and should be redirected to Home Page of Salesforce. How to do that? Please help.  Thank you in advance. Sastri


How to match the camera to the current 3d view without the cropping?

I want to set a camera so what the camera sees is exactly what I see in the viewport.  I know that Ctrl+Alt+Numpad0 will move the camera to my 3D Viewport location, but it also severely crops the sides and sometimes does not show all geometry.  3D Viewport:    Camera view after pressing Ctrl+Alt+Numpad0:    Hitting Ctrl+Alt+Numpad0 crops the camera view, zooms out, and clips off the plane in the background.  How do I make it so that hitting Ctrl+Alt+Numpad0 actually sets the camera view to the 3D Viewport view, without distorting it, clipping geometry, or otherwise altering the view?


It is hard for me to understand what to do to get this badge maybe because English is not my mother tongue language.  The definition is :"Voted on 600 questions and 25% or more of total votes are on questions"  Could you explain please.  Thank you


Why can't I call a function inside a python module without a fully qualified name?

I have the following file structure in a package:  test/ test/__init__.py test/testmodule.py caller.py   On testmodule.py:  def myfunc():     print('wew')   On __init__.py:  from . import testmodule from .testmodule import * __all__ = ['testmodule']   And on caller.py:  from test import * if __name__ == '__main__':     myfunc()   But I get a "NameError: 'myfunc' is not defined". If I do instead test.myfunc(), it works. How can I do from <module> import * so that it works without needing to add the module name to the call?


Azerbaijani citizen with US Green Card, transiting in European airports. Do I need to obtain a Schengen visa?

I will move to the USA from Azerbaijan (I am an Azerbaijani citizen with a Green Card). I am planning to buy tickets with 3 stops: Sofia (Bulgaria), Athens (Greece) and Barcelona (Spain). The transits are within these airports: I will not leave them. Do I need to obtain a Transit Schengen visa?  Here are the details:   [May 22 08:30] Baku GYD - 10:55 Sofia SOF | Azerbaijan Airlines 3h 25m Layover in Sofia for 3h. 13:55 Sofia SOF - 15:10 Athens | ATH Aegean 1h 15m Layover in Athens for 17h 35m. [Wed 23 May 08:45] Athens ATH 11:00 Barcelona BCN | Aegean 3h 15m Layover in Barcelona for 5h. 16:00 Barcelona BCN - 18:15 Boston BOS


So on my android tablet that I've had for about five months I'm getting an error in my notification bar that says storage space running out some system functions may not work. I don't know how to fix it. I first got this notification about a month ago and I managed to uninstall a bunch of apps and download clean master. It fixed the problem for a month. Then it did it again. So I used clean master and still it doesn't work. If I try to get a new app it says insufficient space on device or something like that. It won't let me download apps so don't tell me to download an app. I have downloaded many apps and had them on there at once. I uninstaled a bunch of them and it still won't let me download anything at all. Its not rooted so does any one happen to have a good you tube video or a good way that is fairly simple?


If I understand correctly, gravitational waves are ripples in the fabric of space-time itself created by the movement of mass. Moreover, space and time are just dimensions of the same space-time system.  I wonder if there are waves of space, are there waves of time too?


How can I increase my reputation if I can't answer and I can't vote?

I wasn't active on Stack Overflow for a long time. When I wanted to vote or to post for some question or to leave a comment I found that I have a low reputation. Unfortunately I didn't research a way except to ask questions. Is there any way to increase my reputation?


Can I enter Iran with an expired Iranian passport, while being in possession of a second passport?

I am a Canadian citizen and I am traveling to Iran (back home) this December. My Iranian passport expired on 17/05/2015. I was wondering if I can use it. I want to renew my passport in Iran because it is much cheaper there.


Difference between anti-matter and matter black holes

Laymen question:   Is there any way to determine by observation whether or not a black hole has resulted from the core collapse supernova of a star originally composed of anti-matter versus a star composed of matter? Would there be any implications to say matter falling into a black hole originally formed from anti-matter?  Or is all information lost beyond the event horizon except for mass and spin?


The modern concept of crime and punishment is very reliant on the ability to disarm and restrain and control an individual (think handcuffs, the dividers in police cars, and jails).  How can that be replicated in a world where even a wizard's apprentice has a much power as an armed man with a handgun?  I've seen stories where magical restraints are present, but you can't write that into every thorp and hamlet, even in Eberron.    How can you restrain a magic user in a fantasy setting?   Either answers that conform to modern concepts of crime and punishment or answers about restraining a magic-user in a psuedo-medieval setting are acceptable.


What happens if only one runner reaches base on a double steal?

There are two outs, with men on first and third. The one man leaves first and gets caught in a rundown. The other man steals home as a result. The first man gets tagged out, but not before the other run reaches home.  Is the run counted or not, since the one runner reached home first? That is, BEFORE the out? (In the actual play I'm thinking of, Pittsburgh vs. Atlanta, both men reached.)  Do I assume correctly if the man on first made the second (instead of third) out, that the run is counted?


Expected minimum size of multinomial distribution that includes at least one value of each class

Suppose I have a vector and I include a new item on it at every time step. This item has one of $k$ different classes, each class has probability $\frac{1}{k}$ of being selected.  Suppose now I stop when my vector has at least one item of each of the $k$ classes and let's call the length of this complete vector $n$.  What is the expected value of n?


How can I test all zip files in a folder to verify if they are corrupted or not?

There was a utility a long time ago called CFAtest that was doing this quite nicely, but it has disappeared.  Basically, I am looking for a similar tool (preferably graphical) that will traverse a given path (preferably including subfolders) and test all zip files that it finds.   Decent logging options would be a plus.


Where to put library to allow programs to see it?

I wanted to compile  on my ubuntu machine, but while compiling, I did not have right libpng version, so the compilation aborted with error: error: invalid use of incomplete typedef ‘png_struct’ {aka ‘struct png_struct_def’}   179 |     *width = (int)png_ptr->width;  So I install the ritgh pnglib version: $ wget https://downloads.sourceforge.net/project/libpng/libpng16/older-releases/1.2.21/libpng-1.2.21.tar.gz -O libpng.tar.gz $ tar -xvf libpng.tar.gz $ cd libpng-1.2.21 $ sudo bash configure --prefix=/usr/local/libpng $ sudo make install  which contain the definition for struct png_struct. But now the library is in /usr/local/libpng. So the compilation of the mosaic do not see it (and thus do not have the struct definition and aborts). the library dir is: $/usr/local/libpng$ tree . . ├── bin │   ├── libpng12-config │   └── libpng-config -> libpng12-config ├── include │   ├── libpng12 │   │   ├── pngconf.h │   │   └── png.h │   ├── pngconf.h -> libpng12/pngconf.h │   └── png.h -> libpng12/png.h ├── lib │   ├── libpng12.a │   ├── libpng12.la │   ├── libpng12.so -> libpng12.so.0.59.0 │   ├── libpng12.so.0 -> libpng12.so.0.59.0 │   ├── libpng12.so.0.59.0 │   ├── libpng.a -> libpng12.a │   ├── libpng.la -> libpng12.la │   ├── libpng.so -> libpng12.so │   ├── libpng.so.3 -> libpng.so.3.59.0 │   ├── libpng.so.3.59.0 │   └── pkgconfig │       ├── libpng12.pc │       └── libpng.pc -> libpng12.pc └── share     └── man         ├── man3         │   ├── libpng.3         │   └── libpngpf.3         └── man5             └── png.5  9 directories, 21 files  The question is simple, what directory (e.g. include or lib) should I move elsewhere (e.g. /src/include) in order to make to compilation of mosaic successful (by getting the proper definition it needs)?


Formatting Windows 10 Upgrade without Windows 8.1

This year I installed the Windows 10 upgrade for Windows 8.1 on my computer and now I have a little doubt. Supposing I want to format and reinstall this Windows 10, would I need to first install Windows 8.1 and only then upgrade to Windows 10?  My point here is: first of all, it would be much nicer to just install Windows 10 directly, without having the work of installing Windows 8.1, all the patches needed before the upgrade and only then upgrading. Second, I know the free Windows 10 upgrade is available for limited time. In that case, if I were to do it all over again, I believe this approach would not be valid after some time, since when I did the upgrade I didn't get a Windows 10 product key.  In that case, I'm really in doubt with this. If I want to format and reinstall Windows 10 that I acquired through the upgrade process will I need to first install Windows 8.1 and upgrade again, or is there a shorter path in which I can install Windows 10 directly? In the later the real problem is obviously not in installing Windows 10, but how would I activate Windows if I don't have one Windows 10 product key.


How to install driver for AMD 3550H GPU?

I am wondering if there is a way to install driver for AMD 3550H GPU. I ran the following command on my computer: $ lspci -nn | grep -i vga and the output was: 03:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Picasso [1002:15d8] (rev c2)


How can I get a exFAT drive to (auto) mount?

I have a flash drive that is formatted exFAT and when I plug it into my Ubuntu machine I get a mount error.    How can I auto-mount exFAT formatted drives?


What do "watched tags" and "ignored tags" do?

What are watched tags and ignored tags? How do they work? What are tag subscriptions? What are interesting tags? On Stack Overflow, the content of the main page question list appears to be influenced by watched and ignored tags. How does that work?   For more information, see "" in the .


Is there a term for a date or date/time combination that doesn't exist?

Three (possibly distinct) examples:   A date which never exists/existed, like February 31 A date which was 'skipped' because of calendar changes.  When Russia transitioned from the Julian to the Gregorian calendar it 'skipped' October 26, 1917, among other days. A date/time which was 'skipped' due to a daylight savings change, like 02:01 on 03/27/2011 in the USA   These all appear to be properly formatted, but don't exist, at least in some parts of the planet that recognize the standard US date/time lexicon.   discusses the phrase to show to application users when they choose an invalid date, but invalid date would include 01/blah/-2 and other entries that don't conform to an accepted date format.    I've been using the term irrational date, but I'm not a mathematician and don't know if it is appropriate to compare these situations to irrational numbers.


Best Lens & Camera settings for dance concert with average lighting

I take photos as a hobby and the last 2 years have photographed our annual dance concerts however i would love to improve the quality of my photos. I own a canon EOS 500d and would like some advice on the best lens' and settings to use. Being a small town the lighting at our town hall is average.  Thanks


Is there any place to get browser and version usage by industry?

The company I work for is investigating creating a new product which will be a web application used within hospitals. I am attempting to get concrete numbers on how many hospitals (or percentage of hospitals) are running various OS and browsers (i.e. what % is still using IE6, vs IE7). In general I'm surprised I haven't found anything which grouped browser usage by industry, is anyone familiar with a resource like that?


Did Maeve choose to go and save her child of her own free will?

In the season finale we learn that all of Maeve's escape related activities were       not actually a bug but pre-programmed, despite what Maeve thinks. In other words she had no free will in that scenario.   However at the end of the episode Maeve      sees a child on her escape train and is compelled at the last second to go back for her child.   Is this final action of Maeve a product of her own free will?       Did she 'solve the maze' like Dolores? Or was her return to save her child just as pre-programmed as the rest of her escape attempt?   Is there any specific evidence within the episode (or any other episode in the first season) that explains her actions?


How to restore the partition layout for GPT disk

parted -ms /dev/sda print > sda.parted   This actually copies the layout to a file. If I want to restore the layout, what command should I give?


I installed Ubuntu 14.04 (dual boot with Win 7) and it was working fine. But suddenly one fine day I can't login to my user account, when I log it just flashes and then it goes back to the login screen. But the odd thing is that I can log with the guest account.   I have 2 accounts one owner account/user account and another one created for the installation of Oracle. Only the guest account can login.  From the login screen, I have pressed Ctrl+Alt+F1 to get to a prompt, and login but the same thing happened there too, I entered the correct username and credentials but it flashed and goes back to the login screen.


Story about a student that does not learn like other students

This student doesn't learn by rote and is singled out as an individual thinker that can innovate.  He was fearful that he would not pass his exams about repairing space craft but in the end he proves to be much better than the other students.


Are matter waves and wave function the same thing?

I know that de Broglie proposed that all matter exhibit wave particle duality and that they have a wave associated with them which he called matter wave. But are matter wave and wave function of a particle the same thing? If yes, how? And if no, what is the difference between a matter wave and a wave function?


In the following image:   Why can't current flow across the following wire? It's a simple question, but I've kind off always wondered.  Thanks!


For what orders are there only abelian groups?

It's about that $A_5$ is the smallest non abelian Group. The task is to determine for what orders < 60 there are only abelian groups. My idea was to go through all those orders and use the main theorem about abelian groups. But.. There must be a more elegant solution right? Thanks in advance :)


Where and How should a Stack Exchange user ask questions regarding finding APIs for a specific purpose?

I've been searching through SE-Meta and,from what I can gather, the general consensus is that questions that ask for API & Framework recommendations that can help solve a particular problem are typically marked as "Too Localized" or "Off Topic".  I can understand this reasoning because posting answers to these questions can be problematic.  One of the big reasons (which I do agree with) is that as time progresses, an API can lose support or better APIs could come along and initial answers may become invalid.  Yet, as a developer, I need to find an API or Framework for a specific need in which I'm not to familiar with and having a good recommendation from an expert is invaluable.  Of course, in such a case I start by Googling associated keywords and I tack on "API" to the end of my search.  This usually helps but it doesn't always provide useful results.  For specific needs, it can be difficult to even get a result for an API or framework.    Even worse, there have been occasions where I have found an API, started to use it, and after a month or two of getting my bearings with the API, I'd find out that another API exists, which almost all other developers use and is a considerably better API choice!  Have an expert  or two recommend an API could have saved me weeks (or possibly months) of work if I had started out with the best tool for the job.  With that stated, within the Stack Exchange community is there any away that a user can ask for API recommendations?  It doesn't have to be on Stack Overflow.  If such questions are acceptable on Stack Overflow, what guidelines dictate which API recommendation requests are acceptable and which are not?  I'm a bit confused but I'd imagine there is a way within SE that I can get these types of questions answered by those who are quite familiar within the area of my new development needs.


So this here questions got me stuck for a bit:     Determine whether S is a subspace of V, if yes find a basis and its   dimension. Let $S$ be the set of all 3x3 symmetric matrices in $V =  M_{3x3}$   And here's why: I checked the appropriate axioms and it turns out S is in fact a subspace of V, but my main problem is that before this exercise, to find a basis, I'd find the augmented matrix and solve it (RREF) and then determine the solution, but here I'm not sure if I can.  So I have an approach but not sure which if it works:   If I say for e.g.   Assume the matrix $A=\begin{pmatrix}     a &  b & c\\     b & d & e\\      c & e & f\\ \end{pmatrix}$  if det(A) $\neq 0$ => linearly independent => the basis exists.  $k_1\begin{pmatrix}     a\\     b\\      c\\ \end{pmatrix}$ + $k_2\begin{pmatrix}     b\\     d\\      e\\ \end{pmatrix}$ + $k_3\begin{pmatrix}     c\\     e\\      f\\ \end{pmatrix} = 0;  dim(S) = 3$  Please let me know how to go about this. Thank you.


Outline of a proof that $\mathbb{R}^2 - A$ where A is countable is path-connected

Let $A$ be a countable subset of $\mathbb{R}^2$. Show that $\mathbb{R}^2-A$ is path connected.  These are my steps:   Let $x$ and $y$ be arbitrary points of $R^2$ Let $f^r:[0,1] \to \mathbb{R}^2$ be given by $f^r(t)=(1-t^r)x+t^ry$ for $r \in\mathbb{R}$.  Show that $f^r$ is a continuous path between $x$ and $y$ and that non of them intersect. Show that $f^r$ is bijective with $\mathbb{R}$ through $F(f^r)=r$ and conclude that there are uncountable non intersecting paths. Assume for the sake of contradiction that $A$ intersects all of the paths $f^r$ and deduce that $A$ must be uncountable (since it must intersect every $f^r$ at a different point).  Contradiction! ($A$ is countable) Hence there exist a paths $f^r$ for some $r \in\mathbb{R}$ which doesn't intersect $A$. $\mathbb{R}^2-A$ is path-connected.     Is this proof sound?


Word for a cushy position awarded to a crony?

I'm struggling to recall this word. If I recall correctly, it's of French origin. My search has so far been fruitless.   The nearest equivalent I came up with was the idiom  but that is obviously English and not a single word.     pull strings / wires   (a) to use one's influence or authority, usually in secret, in order to bring about a desired result.   (b) to gain or attempt to gain one's objectives by means of influential friends, associates, etc.:      He had his uncle pull strings to get him a promotion.


Using PostGis BBox and ST_intersects Queries?

CartoDb Recommend  that the following query is faster than an St_intersects Query  SELECT * FROM {table_name} WHERE the_geom && ST_SetSRID(ST_MakeBox2D(ST_Point(-73.9980, 40.726), ST_Point(-73.995, 40.723)), 4326)   I have the following Query that works just fine and returns GeoJson as needed,   WITH c AS (SELECT -73.976440429688, 40.743095232182, -73.970947265625, 40.738933241136, 4326 As srid)  , bbox AS (SELECT ST_Transform ( ST_MakeEnvelope( -73.976440429688, 40.743095232182 ,-73.970947265625 , 40.738933241136 , 4326) , 900913 ) As geom FROM c ) SELECT row_to_json(fc)     FROM ( SELECT 'FeatureCollection' As type, array_to_json(array_agg(f)) As features     FROM (SELECT 'Feature' As type, osm_id As id,         ( SELECT row_to_json(t)           FROM (SELECT osm_id, "name" ) t )As properties,          ST_AsGeoJSON(ST_Transform (lg.way ,4326 ) )::json As geometry      FROM planet_osm_polygon As lg, bbox         WHERE ( building is NOT NULL) AND ST_Intersects(lg.way, bbox.geom)             ) As f ) fc;                   I have been trying to create the same JSon result using ST_MakeBox2D in a similar fasion to the CartoDb example and failing miserably.  My objective is to have the fastest possible query for any geometry that any part of itself WITHIN the bounding box.  My Questions are:   Which method will return the fastest possible result, assuming that the Columns in the WHERE clause are indexed properly? How do I change my query to use St_makeBox2D with the geom && syntax as per the CartoDb Example?


I've searched all over meta and found  for wearing multiple hats that was . But today I saw  profile.     Is there really a way to wear two hats or is this something out the ordinary?


Isoperimetric inequality on the sphere via calculus of variations

The isoperimetric inequality on the sphere of radius 1 asserts that for any closed curve on the sphere, $$L^2 \geq A(4\pi - A)$$ where $L$ is the length of the curve and $A$ is the area it encloses.  There are a number of proofs of this; I am looking for a proof using the calculus of variations in the spirit of the proof of the standard isoperimetric inequality on the plane.  I don't think this can be done, but I thought I'd see if others have an idea.  First, let us review the variational proof of the isoperimetric inequality on the plane.  By Green's theorem, the area enclosed by a curve $(x(t), y(t))$ is given by: $$A = \int_a^b x(t)y'(t)\, dt$$ On the other hand the length is given by: $$L = \int_a^b \sqrt{x'(t)^2 + y'(t)^2}\, dt$$ Using Lagrange multipliers, we can maximize $A$ while treating $L$ as a constraint, and the isoperimetric inequality follows.  To adapt this idea to the sphere we would need to use Stokes' theorem instead of Green's theorem to manufacture a line integral which calculates surface area.  Namely, we would need a vector field $\textbf{F}$ on $\mathbb{R}^3$ such that if $C$ is a closed curve on the sphere which is the boundary of a piece $S$ of the sphere then: $$\int_C \textbf{F}\cdot \textbf{T}\, ds = \iint_S \text{curl}\, \textbf{F} \cdot \textbf{n}\, dS = \iint_S dS$$ In other words we want to choose $\textbf{F}$ so that $\text{curl}\, \textbf{F} = \textbf{n}$, the outward unit normal vector of the sphere.  But there can be no vector field in $\mathbb{R}^3$ whose curl is $\textbf{n}$ since the integral of $\textbf{n}$ over the sphere is $4\pi$ while the integral of the curl of a vector field over any closed surface is $0$ by Stokes' theorem.  This seems to suggest that you can't use the calculus of variations to prove the isoperimetric inequality on any closed surface, which is a bit disappointing.  Is there any way to get around this problem?


What are the requirements for a house in mobile Terraria?

Background: I built a nice village with NPCs. I have also built a "wall" out of wooden beams and some "towers" at the side ends. After a goblin invasion, we had some casualties, so I decided to remove the houses and build an apartment kind of building.   But, I ran into another problem. I built the first floor—it worked fine, but in the second floor, none of the NPCs moved in, and that's the problem. What could be wrong? Any help would be appreciated.


Books for Condensed Matter after Ashcroft/Mermin

What are some good condensed matter physics books that can fill the gap between Ashcroft & Mermin and research papers? Suggestions for any specialized topics (such as superconductivity, CFT, topological insulators) are welcomed.


Do f-stops scale with sensor size the way focal length does?

Does the aperture rating scale with sensor size the way focal length does?  For example, is a 25mm 1.2 MFT lens equivalent to a 50mm 1.2 FF lens or to a 50mm 2.0 FF lens?


Anomalous expansion of water when heated

In one question I found that when water was heated from 0°C to 15°C then the volume 1st decreases and then increases why is that so ?


Prove that if matrix $A$ is nilpotent, then $I+A$ is invertible.

So my friend and I are working on this and here is what we have so far.  We want to show that $\exists \, B$ s.t. $(I+A)B = I$. We considered the fact that $I - A^k = I$ for some positive $k$. Now, if $B = (I-A+A^2-A^3+ \cdots -A^{k-1})$, then $(I+A)B = I-A^k = I$. My question is: in matrix $B$, why is the sign for $A^{k-1}$ negative? Couldn't it be positive, in which case we'd get $(I+A)B = I + A^k$?  Thank you.


LaTeX command \mathbb gives strange results when using numbers.   For example, \mathbb{1} prints an unintended symbol.   There was a previous question on this topic whose solution involved using the \mathbbol package, but it doesn't seem to be working anymore. The solution posted originates a compilation error.


This is a bug report originating from   In the reputation tab, When a user hovers over a row of his rep:    the cursor changes to a pointer. The problem around the pointer is that The table-row  has the class expandable-row which actually sets the cursor to pointer. But only the post body is actually expandable. Therefore, clicking on the row does not work. You need to click on the post body (or the arrow to the left of it).  Either the row should be made expandable by clicking anywhere on it, or the cursor should not change to pointer on hovering over the row, instead it should do so only on hovering over the rep-body cell.


I have a Apex Class like below for handling the exception   public class updateCaseRecord {          @AuraEnabled     public static void updateCheck(String caseId, String Status){         String msg = '';         try         {         List<Case> records = [select id,Status from Case WHERE Id = :caseId];         for (Case record : records)         {              record.Status = 'Closed';         }                    update records;          }         catch(DmlException e)              {                for (Integer i = 0; i < e.getNumDml(); i++) {                     msg =+ e.getDmlMessage(i) +  '\n' ;                     System.debug('getDmlFieldNames=' + e.getDmlFieldNames(i));                    System.debug('getDmlMessage=' + e.getDmlMessage(i));                   }                 throw new AuraHandledException(msg);             }             catch(Exception e)             {             throw new AuraHandledException(e.getMessage());             }             finally { }           }      }   I wrote the test class like below where was able to throw the DML exception by breaking the validation rule and it works   @IsTest public class updateCaseRecordTest {     @IsTest static void testIsUpdateCheck() {       ...........      ...........      Test.startTest();          try         {            .............             // below Call to the method updateCheck() will fail due to the Validation error throws the DML Exception             Status4 = 'Close';             updateCaseRecord.updateCheck(newCase3.Id,Status4);          }                  catch(AuraHandledException e) {             System.assertEquals(e.getMessage(), e.getMessage());         }          Test.stopTest();        }}   But I cannot execute the Exception e catch block after running the test class I see like below     How to execute the other Catch block.


Run a command in the middle of a script as root

I need that in the middle of a script in bash a line be executed as root, I have this code:  #!/bin/bash ... EOF  if [[ $x = true ]] || [[ $y= "On" ]]; then echo -e "0 8    * * *   root " >> /etc/crontab   I need the echo written in the crontab by the root user, who has a password. Currently it does not write as it is executed by the ubuntu user. Thank you.


I'm trying to figure out how to make a stair case along a complicated bezier curve.  The stairs are just made of wooden planks, so it's simple model, I'm just having trouble keeping them all level and flat and following the curve correctly.  Is there a way to keep the rotation of the planks as zero instead of following the normals of the bezier curve?


How to tell if your edit to a question is rejected

Can someone tell me how to tell if my edit to a question is rejected?  It might be obvious, but I'm not sure.  When I made the edit the question had this text:     This edit will be visible only to you until it is peer reviewed.   I revisited the page a half hour later and don't see any evidence of the edit.  If this means the edit was denied, is there a way to find out why?  Is there any history log of what happened?  The user wrote:     How Linux differs from other scripting languages?   It appeared clear to me that the user meant:     How Does Using Linux differs from other scripting languages?   There were three or four other small edits in the body that also made the question clearer.  The user had made comments in the comment section that showed he was referencing scripting in the Linux environment.  So, being new (me) in editing questions to make them clearer to the community, I'm wondering is my edit had been rejected or is still pending.  The question:


Opening NEF files on windows initially open fine but then change contrast

I have a strange issue with Windows 10  When I open .nef files they load fine. However after a second or two the contrast changes noticeably. I tried Windows 10 Photos and Picasa Image Viewer.   What am I trying to accomplish? I just want to open files quickly to check for focus and composition before importing into Lightroom  Lightroom does not have this issue   Here is the example opening with Windows 10 Photos    And here is after a second when it 'fully' loads    Picasa Photo Viewer after it loads a bit. It initially opens fine but then it goes all purple


Dual Boot - How to access Windows partition without having to shut down Windows

Currently, when I restart from Windows to Ubuntu, or if I hibernate Windows and boot Ubuntu, I can't access my Windows partition.  I have to restart from Ubuntu to Windows, then shut down Windows, then boot Ubuntu again.  Is there another way around this?  Error mounting /dev/sda5 at /media/user/Windows8_OS: Command-line `mount -t "ntfs" -o "uhelper=udisks2,nodev,nosuid,uid=1000,gid=1000,dmask=0077,fmask=0177" "/dev/sda5" "/media/user/Windows8_OS"' exited with non-zero exit status 14: Windows is hibernated, refused to mount. Failed to mount '/dev/sda5': Operation not permitted The NTFS partition is in an unsafe state. Please resume and shutdown Windows fully (no hibernation or fast restarting), or mount the volume read-only with the 'ro' mount option.


Why is the word "welcome" spelled with one "l"?  Somewhere in the answers I found a good explanation of the meaning of " welcome".   Example: "You have done well to come to me; I am pleased to do it"  According to this meaning, "welcome" should be spelled with two L  Where in the history did the change take place?