Win10: How can I delete driver files? (C:\Windows\System32\DriverStore\FileRepository)

My situation and goal: I have a Asus Laptop which I upgraded from Win7 to Win10 a year ago. So far so good. My Account is since ever defined as administrator, but actually it can't proceed administrator tasks.  I want to delete driver files. The path is in the title of the question. My account is an administrator account but I can't delete files in this folder.   When I move files from folder A to folder B it happens that I have to confirm moving them or I have to give allowance to applications to install files. This experiences brought me to the point that I see something with the administrator rights is not correct. I assumed that my account has problems with the administrator rights and I have to fix these before I can delete the targeted files.  What I tried to solve the administrator issue:  I tried several ways to get administrator rights.  1) I tried to change account typ from standard to administrator. Not possible, because when I choose this option the button to accept the choice gets inactive. button gets inactive when I select administrator. And as you can see the account is defined as administrator, but is from type standard.    2) I activated an administrator account via cmd-window and "net user administrator /active:yes". It worked but this account is not able delete files which need administrator rights. It seems this account is an administrator account but has not the rights for it.  3) I tried to change the administrator rights for my standard account and administrator account in "Save mode" of windows. the same situation like in point 1.  4) By solving the administrator issue, I found out that my windows lakes functionalities. I wanted to take control over this problem by using the "Computer Manager", but the area where you can manage accounts and group is not existing. The local group policy window doesn't work. (see below in the comments the screenshots)  Something in the system is messed up. What is wrong or what else can I do to make it possible to control this kind of files in Windows 10?


Unable to locate package boot-repair in 14.04

I've tried to install boot repair and failed  sudo add-apt-repository -y ppa:yannubuntu/boot-repair && sudo apt-get update   The error is:  $ sudo apt-get install -y boot-repair Reading package lists... Done Building dependency tree        Reading state information... Done E: Unable to locate package boot-repair   I've never had this error before on other versions of Ubuntu or Mint, though.


How to run a command or script at screen lock/unlock?

I am looking for a way to store lock/unlock screen times.  A=$(date) echo $A >> $HOME/time_xprofile   What did I try:  $HOME/.bashrc $HOME/.bash_logout $HOME/.bash_prompt $HOME/.xprofile   Then I locked the screen and checked whether file appeared and it failes every time. How can I check the time than?


How to prove the following inequality $|\prod_{i=1}^{i=n}a_i-\prod_{i=1}^{i=n}b_i| < n\delta$?

The constraints are   $0 \le a_1,a_2....a_n,b_1,b_2....b_n \le 1$. $|a_i-b_i|< \delta$ for all $1 \le i \le n $   How do I go about proving the following $$|\prod_{i=1}^n a_i-\prod_{i=1}^n b_i| < n\delta$$  I tried reducing it to two terms where one term is like $(a-\delta)^n$ so that I can get the $n\delta$ term from binomial,but I am stuck. I would really appreciate just hints.


Well, I really tried to solve (and google) it, but I couldn't.  And sorry for my english and for that idiotic title (This one is the best that came to mind) :)   System.out.println("AM I A GENIUS?"); Scanner scan = new Scanner(System.in); String s = scan.nextLine();  if (s == "yes"){         System.out.println("^_^"); }  else{     System.out.println("I am not a genius("); }   console: AM I A GENIUS?  yes  I am not a genius(


The exact mechanism of energy release durning bond formation on the atomic level

Image a situation:   We have two atomic hydrogen atoms.  We magically collide them together dead center and perpendicular.  Each atom has exact amount of kinetic energy. We collide them with precisely enough energy to form molecular hydrogen (H2). Chemical reaction occurs: H + H -> H2 + energy My question is:    How the bond formation energy is being released?  Is it some kind of EM radiation? Photons? 2.1. If it is photons, what determines their energy and direction? If it is not EM, what is it? Vibration of the new molecule? 3.1. If it is "vibration" why does the hydrogen molecule do not decay into two atomic hydrogen?  Is there only one mechanism of energy release? Does it depends on the bond type?    I tried to search, but I can find only formulas/laws without a description how does it happens in 3D space, step-by-step with drawings/schemas/simulations.


Which of the following is correct? If both are acceptable which is preferred?  Our product lets you manage all of your stuff in one easy place. Our product lets you manage all of your stuff in one, easy place.


Will free-fall object into black hole exceed speed of light $c$ before hitting black hole surface?

In Newtonian mechanics, if we throw an object in against direction of gravity with speed $v$ and it achieve max height of $h$. Now if we allow object to fall from that height $h$, it will eventually attain speed $v$ when it reach position where we launch it.   Now applying same idea to a black hole in general relativity. Speed require to escape black hole gravity is greater than $c$, so if we throw something into black hole with almost the speed of light, the object speed will exceed speed of light $c$ before hitting black hole surface! How relativity explain this? Can space-time curvature reduce speed of this freely falling object from attaining speed of light?


Android and sqlite, can I populate a database before upload?

I have an app that just need to read from a database. I do not want to parse a big file in the app because it takes a lot of memory.  So is it possible to populate a database and ship it with the app?  Just parsing the file and storing it in the app the first time the app is run will not do since it will create the same memory problem.  An alternative would be to have the database on Google Appengine but I would like to avoid that because the app would be unusable if there is no internet connection and there are costs for the traffic.


ffmpeg deprecated pixel format used, make sure you did set range correctly

I want to convert pictures into a video. Version = ffmpeg-4.3-win64-static I keep getting this error on Frame 865 of 17311 Running through powershell as Admin. ./ffmpeg.exe -r 30 -f image2 -start_number 10002 -i ./G0%06d.JPG -c:v libx264 -pix_fmt yuv420p video.avi ./ffmpeg.exe -r 30 -f image2 -start_number 010002 -i ./G0%6d.JPG -c:v libx264 -pix_fmt yuv422p video.avi


Clarification on Rayleigh scattering causing various sky colors

(I know Rayleigh scattering isn't the only reason why the sky is blue but to simplify the question lets focus on that)  The commonly stated reason for why the sky is blue is that smaller wavelengths are scattered more easily off the molecules in the air. During the day, because the blue light is scattered more, the sky is illuminated more with that blue light and more reaches your eyes. However, during sunsets and sunrises, the light from the sun must travel a longer distance. The explanation I have found is that the blue light is scattered away and more of the longer wavelength reds and greens are available to reach your eyes to get those warmer colors, (red and green of course mixing to get yellows).   My question is that it seems like these explanations are conflicting. If the light at sunsets and sunrises travels more distance, why won't the blue light be scattered even more and thus illuminate the sky with blue light more than in the daylight? It confuses me that in one case the scattering of blue light causes the sky to be blue but then at sunset the scattering eliminates this color. Could I get some explanation on this?


I'm working on a small game and i'd like to know how can i write/read a user settings file in ubuntu touch?


How to automatically turn off hard drive when not used?

I have a noisy hard drive I rarely use and want to silent. I would like to put it in sleep mode after some time (20 sec) when it's not mounted on the system.  The gnome-disks utility shows a "standby timeout" option:    The hard drive never gets to sleep automatically; I can manually put it to sleep/wake it up with the gear menu:   Why does my drive doesn't automatically go to sleep? How can I make it go to sleep automatically after no activity?


My disk space is rapidly getting eaten up and I don't know why.  I was using localhost and it was taking a long time to load so I checked the properties in the folder and I had 2GB left out of 125GB on my SSD.  What is causing this error and how do I fix it?


How to get a small letter version of \mathcal{O}

I am trying to produce a small letter version of \mathcal{O} which looks the same, just smaller - like "O" and "o". However \mathcal{o} produces a very different symbol. Has anyone an idea how to manage this?


I am attempting to create a 4d array and assign variables to each of the cells.  Typically I would use four "for loops" but this is very messy and takes up a lot of space.  What i'm currently doing:  for x in range(2):     for y in range(2):         for j in range(2):             for k in range(2):                 array[x,y,j,k] = 1 #will be a function in reality   I've tried using list comprehension but this only creates the list and does not assign variables to each cell.  Are there space-efficient ways to run through multiple for loops and assign variables with only a few lines of code?


Cannot locate package via terminal ubuntu 16.04lts

i want to install three packages from terminal ubuntu 16.04 lts   when i run command sudo apt-get install aclocal  this is the output i get ...    ->   Reading package lists... Done Building dependency tree        Reading state information... Done E: Unable to locate package aclocal   i also tried sudo apt-get update and sudo apt-get upgrade but then again unable to install   i also want to install package libtoolize  , pkgconfig aswel i think they are not available in automake .  my os has latest version of automake but its still unable to locate package aclocal.  i am new to ubuntu  thanks


Overlaying an image to cover a face in a video?

I am trying to make a youtube video and in the part of the video I'm going to have a image of a face on top of my face to preserve my privacy. I tried going frame by frame with a picture that has a transparent background but somehow it didn't work.


You have earned the "xxx" badge back button bug

Browser: Chrome  When the bar at the top of the page appears when you earn a badge, and you then navigate to another page (I clicked on the recent icon), then go back, the bar reappears each time.


I am trying to create a user profile section in my app. In my Login Activity, I ask for the username from FirebaseAUTH.getCurrentUser().getDisplayName() and save it in a string.  In my xml file for the main activity, I put a textView with a string containing a placeholder.  I tried both in the Login and the Main Activity Java files to .setText .format etc, but the text simply doesnt change..  Any hints on how to solve this?   public class MainActivity extends AppCompatActivity     implements NavigationView.OnNavigationItemSelectedListener {     private HomeFragment hf;     private WebViewFragment wvf;     protected void onCreate(Bundle savedInstanceState) {      super.onCreate(savedInstanceState);      setContentView(R.layout.activity_main);       Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);      setSupportActionBar(toolbar);       firebaseAuth = FirebaseAuth.getInstance();      if (firebaseAuth.getCurrentUser().getDisplayName() != null) {         String name = firebaseAuth.getCurrentUser().getDisplayName();         final TextView profile = (TextView)findViewById(R.id.profile_section);         profile.setText("Test");     }   E/AndroidRuntime: FATAL EXCEPTION: main                   Process: com.example.vreeni.firebaseauthentiction, PID: 6060                   java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.vreeni.firebaseauthentiction/com.example.vreeni.firebaseauthentication.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference                       at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2822)                       at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2897)                       at android.app.ActivityThread.-wrap11(Unknown Source:0)                       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1598)                       at android.os.Handler.dispatchMessage(Handler.java:105)                       at android.os.Looper.loop(Looper.java:251)                       at android.app.ActivityThread.main(ActivityThread.java:6563)                       at java.lang.reflect.Method.invoke(Native Method)                       at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)                       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)                    Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference                       at com.example.vreeni.firebaseauthentication.MainActivity.onCreate(MainActivity.java:52)                       at android.app.Activity.performCreate(Activity.java:6975)                       at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214)


I created a second bootable volume called "Beta" in order to install the macOS Catalina beta. I successfully installed and booted to this new volume, but when I returned to the first volume (which has macOS Mojave installed) I was surprised to see a third volume.    The "Beta - Data" seems to have been created during the installation process. This third volume is also not visible when I return to the "Beta" boot volume, only having the "Beta" and "Panther" volumes. The "Beta" volume when booted into it also seems to have the combined size of the "Beta" and "Beta - Data" volumes.   I originally created the "Beta" volume with a quota of 256GB as well, but that quota is gone from that volume and the "Beta - Data" volume seems to have inherited it.  The "Beta" volume seems to contain the system install; containing the home, Library, System and Users directories (though the Users directory only contains the Shared directory, and not the home folder for the user I created). While the "Beta - Data" volume has the user-specific data; having the Device, private and Users directories (with the home folder for the user I created within, as well as another Shared directory).  I have never tried dual booting on a Mac before, so this could be more common than I am aware of, but I couldn't seem to find any information on why this would happen or where this volume came from. Could this be a new "feature" (or bug) from macOS Catalina? Or did I just do something wrong when I created the new volume?


App keeps crashing due to error in text input

My project partner's code keeps crashing when I press a button to launch it in android studio.  This is the error I get in the logcat. Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.text.Editable android.widget.EditText.getText()' on a null object reference.   This refers to line 21 where: String fullName = name.getText().toString();  help?  @Override protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.activity_main);        Intent intent = new Intent(MainActivity1.this, SecondActivity.class);      EditText name = (EditText)findViewById(R.id.entName);     String fullName = name.getText().toString();     intent.putExtra("name_key", fullName);      EditText ages = findViewById(R.id.age);     String age = ages.getText().toString();     intent.putExtra("age_key", age);      RadioGroup gender = findViewById(R.id.genRGroup);     int genderPos = gender.getCheckedRadioButtonId();     int male = findViewById(R.id.male).getId();     int female = findViewById(R.id.female).getId();     String gen;      if (genderPos == male) {         gen = "Male";     } else if (genderPos == female) {         gen = "Female";     } else {         gen = "Other";     }     intent.putExtra("gen_key", gen);      Button theBtn = findViewById(R.id.addAPersonButt);     theBtn.setOnClickListener(new View.OnClickListener() {         @Override         public void onClick(View v) {             Intent intents = new Intent (MainActivity1.this, MainActivity2.class);             startActivity(intents);         }     });      Button conButt = findViewById(R.id.confirm);     conButt.setOnClickListener(new View.OnClickListener() {         @Override         public void onClick(View v) {             Intent intent = new Intent(MainActivity1.this, SecondActivity.class);              EditText name = findViewById(R.id.entName);             String fullName = name.getText().toString();             intent.putExtra("name_key", fullName);              EditText ages = findViewById(R.id.age);             String age = ages.getText().toString();             intent.putExtra("age_key", age);              RadioGroup gender = findViewById(R.id.genRGroup);             int genderPos = gender.getCheckedRadioButtonId();             int male = findViewById(R.id.male).getId();             int female = findViewById(R.id.female).getId();             String gen;              if (genderPos == male) {                 gen = "Male";             } else if (genderPos == female) {                 gen = "Female";             } else {                 gen = "Other";             }             intent.putExtra("gen_key", gen);              startActivity(intent);         }     });  }   }


How do you split a list into evenly sized chunks?

I have a list of arbitrary length, and I need to split it up into equal size chunks and operate on it. There are some obvious ways to do this, like keeping a counter and two lists, and when the second list fills up, add it to the first list and empty the second list for the next round of data, but this is potentially extremely expensive.  I was wondering if anyone had a good solution to this for lists of any length, e.g. using generators.  I was looking for something useful in itertools but I couldn't find anything obviously useful. Might've missed it, though.  Related question:


Watching or to watch. Which one is correct in these two sentences?

Is it ok to say:  Then, I started watching an episode of...  or should I say  Then, I started to watch an episode of...  Which one is correct or are both correct? Can you explain me what's the difference between these two sentences? I would really appreciate your help, thank you so much.


Attacks of the MAC construction $\mathcal{H}(m\mathbin\|k)$ for common hashes $\mathcal{H}$?

Consider a common practically-collision-resistant hash function $\mathcal{H}$ (e.g. , , , ), perhaps based on the  as are the first three. We define a  $\mathcal{C}$ $$(k,m) \mapsto \mathcal{C}(k,m)=\mathcal{H}(m\mathbin\|k)$$ where $\mathbin\|$ denotes concatenation, $k$ is a secret key (constant, or at least of fixed size), and $m$ is a message (possibly of variable length). Assume that an adversary can (iteratively) submit queries with $m_j$ and obtain $C(k,m_j)$, and wants to obtain $k$ or otherwise compute $C(k,m)$ for some $m\ne m_j$.  That MAC $\mathcal{C}$ is not trivially bad. In particular, if $\mathcal{H}$ was indistinguishable from a random function in the , $\mathcal{C}$ would be secure. And even though $\mathcal{H}$ may have the , it does not turn into a devastating attack on $\mathcal{C}$.  The less impractical generic attack that I see is that if a collision was known for $\mathcal{H}$ with the colliding messages of moderate identical length, it could be deduced countless collisions for $\mathcal{C}$. Hence security is demonstrably not better than collision-resistance of $\mathcal{H}$ (for identical-length messages). We could assume that $k$ is half the size of the result of $\mathcal{H}$, and hope that the security is about  or  or , 280, 2128, 2256 hash rounds for SHA-1, RIPEMD-160, SHA-256, SHA-512.   What are the known attacks against $\mathcal{C}$ (better than the above), and their cost, for each of these common hashes?  Is there hope for an argument that an attack against $\mathcal{C}$ would turn into an attack of similar cost against $\mathcal{H}$, or hint of the contrary?  Update: this  is of interest, but I fail to find that it really answers the present question.  Update 2: I am aware that the construction considered is weaker than , and in particular is vulnerable to collision on $\mathcal H$; I stated that, and that it is thus pointless to have the key wider hopeless to target security against some attacks better than half the hash's size. I'm asking exactly what cryptanalytic attack better than finding a collision on $\mathcal H$ there are. There is room for such an attack only by exploiting a weakness in the structure or/and the round function of a concrete $\mathcal H$.


How can you write to a file from the command line without using shell output redirection?

I'm trying to:   sudo echo "$USER: my message" > /dev/kmsg   to write a message to the dmesg log.  This causes a 'permission denied' error, because it is redirecting the output of 'sudo' (while no longer privileged) to /dev/kmsg.  So the 'echo' command is running as root and the writing to /dev/kmsg is running as me.  Quoting 'echo' command and ther the redirect ('>/dev/kmsg') doesn't work because the redirection is a shell service that sudo doesn't understand.  (The userid in question is in sudoers with NOPASSWD.)  Is there some Linux command that takes the file name as an option and writes its arguments out?  Like:  'tee /dev/kmsg -- My message to be logged'   I know about the 'logger' command, but that doesn't write to whatever log file 'dmesg' sees.  (I want to intersperse some of my messages in with the boot process to know when certain things happen.)  This works, but has the problem of needing to have some place to write a file to:  echo "$USER: My msg" >/tmp/foo sudo cp /tmp/foo /dev/kmsg rm /tmp/foo   Solution from ctrl-alt-delor's comment below:  echo "my message" | sudo tee /dev/kmsg >/dev/null   Although it does use piping and redirection, it occurs in the unprivileged shell.  Privileged access to '/dev/kmsg' occurs in the 'tee' command in 'sudo'.  And it doesn't need write to a disk file (which could have problems).   Also @stolenmoments solution:  echo something | sudo dd of=/dev/kmsg


How to pack an installed ubuntu system into an ISO file?

I find an image on AWS in ami format which is my target.  I need to download the target OS image to my local system and install it on my local cluster computers. (There is no direct support for exporting ami image into iso file.)  Is it possible? How can I achieve it?


I want to get other process' argv like ps.  I'm using Mac OS X 10.4.11 running on Intel or PowerPC.  First, I read code of ps and man kvm, then I wrote some C code.  #include <kvm.h> #include <fcntl.h> #include <stdio.h> #include <stdlib.h> #include <sys/sysctl.h> #include <paths.h>  int main(void) {     char errbuf[1024];     kvm_t *kd = kvm_openfiles(_PATH_DEVNULL, NULL, _PATH_DEVNULL, O_RDONLY, errbuf);     int num_procs;     if (!kd) { fprintf(stderr, "kvm_openfiles failed : %s\n", errbuf); return 0; }     struct kinfo_proc *proc_table = kvm_getprocs(kd, KERN_PROC_ALL, 0, &num_procs);      for (int i = 0; i < num_procs; i++) {         struct kinfo_proc *pproc = &proc_table[i];         char **proc_argv = kvm_getargv(kd, pproc, 0);         printf("%p\n", proc_argv);     }      kvm_close(kd);     return 0; }   When ran on PowerPC, kvm_getargv() always returned NULL.  When ran on Intel, kvm_openfiles() failed with error /dev/mem: No such file or directory.  Of cource, I know about permission.  Second, I tried sysctl.  #include <sys/sysctl.h> #include <stdio.h> #include <stdlib.h> #define pid_of(pproc) pproc->kp_proc.p_pid  int main(void) {     int mib[4] = { CTL_KERN, KERN_PROC, KERN_PROC_ALL, 0 };    int buffer_size;    sysctl(mib, 4, NULL, &buffer_size, NULL, 0);     struct kinfo_proc *result = malloc(buffer_size);    sysctl(mib, 4, result, &buffer_size, NULL, 0);     int num_procs = buffer_size / sizeof(struct kinfo_proc);    for (int i = 0; i < num_procs; i++) {        struct kinfo_proc *pproc = result + i;        int mib[3] = { CTL_KERN, KERN_PROCARGS, pid_of(pproc) }; // KERN_PROC_ARGS is not defined        char *proc_argv;        int argv_len;        sysctl(mib, 3, NULL, &argv_len, NULL, 0);        proc_argv = malloc(sizeof(char) * argv_len);        sysctl(mib, 3, proc_argv, &argv_len, NULL, 0);        fwrite(proc_argv, sizeof(char), argv_len, stdout);        printf("\n");        free(proc_argv);    }     return 0; }   By fwrite, I got argv[0] but argv[1..] are not (environment variables are printed out.)  There is no more way to do it?


c++ - automatic casting with derived class

I have a class called Action, and a MoveAction which derives from Action and I have an object which holds a variable: Action action_to_perform. Now I assigned a new MoveAction to this variable. These Action classes holds a method perform(). MoveAction does something else than Action's perform. When I call  object->action_to_perform   then it calls Action's perform method, when it's set to a MoveAction object. How can I automatically cast it a MoveAction?  EDIT:  Action.h:  class Action { public:     Action();     virtual ~Action();      virtual void perform(); protected: private: };   MoveAction.h:  class MoveAction : public Action { public:     MoveAction(int, int);     virtual ~MoveAction();      int dx, dy;      virtual void perform(); protected: private: };   In Player.cpp:  Action action_to_perform; ... action_to_perform = MoveAction(0, 1);


After discussion with colleagues regarding the use of the 'var' keyword in C# 3 I wondered what people's opinions were on the appropriate uses of type inference via var?  For example I rather lazily used var in questionable circumstances, e.g.:-  foreach(var item in someList) { // ... } // Type of 'item' not clear. var something = someObject.SomeProperty; // Type of 'something' not clear. var something = someMethod(); // Type of 'something' not clear.   More legitimate uses of var are as follows:-  var l = new List<string>(); // Obvious what l will be. var s = new SomeClass(); // Obvious what s will be.   Interestingly LINQ seems to be a bit of a grey area, e.g.:-  var results = from r in dataContext.SomeTable               select r; // Not *entirely clear* what results will be here.   It's clear what results will be in that it will be a type which implements IEnumerable, however it isn't entirely obvious in the same way a var declaring a new object is.  It's even worse when it comes to LINQ to objects, e.g.:-  var results = from item in someList               where item != 3               select item;   This is no better than the equivilent foreach(var item in someList) { // ... } equivilent.  There is a real concern about type safety here - for example if we were to place the results of that query into an overloaded method that accepted IEnumerable<int> and IEnumerable<double> the caller might inadvertently pass in the wrong type.  var does maintain strong typing but the question is really whether it's dangerous for the type to not be immediately apparent on definition, something which is magnified when overloads mean compiler errors might not be issued when you unintentionally pass the wrong type to a method.


So I'm a newbie in Blender, and when I rendered the model, there were some annoying black pixels. Can you help me?


Travelling to a different Schengen country than the Schengen Visa

I am the spouse of a UK citizen and have been granted a Schengen visa for Germany. However due to some of my plans falling through, I will no longer be visiting Germany. I was wondering if it's OK for me to visit France on this visa with my spouse or if I need to wait and apply for a French Schengen visa.  Thanks


If R is an integral domain disprove the RxR is an integral domain?

I am trying to prove that given R (an integral domain) it is not true that then RxR is an integral domain:  We know that for the ring Zp for any prime p, Zp is an integral domain because it is a ring with unity 1 not equal to 0, and it has no zero divisors. The ring Zn for any n not prime is not an integral domain because it does have zero divisors. From here would it be sufficient to show that given R= Z5, we know that Z5 must be an integral domain because 5 is prime. However RxR would give us Z25 which is not an integral domain because n=25 and is not prime???


Why didn't they use magic to fix Hogwarts in the last book?

In the sixth movie, at the house Slughorn was hiding in, there was a mess. Later Dumbledore used magic to clean it all up very fast. After Hogwarts was destroyed in the last book, why didn't all the teachers use magic to fix it? You could see Filch cleaning it up with a broom, even though Dumbldore had the Elder Wand (to clean up Slughorn's damage at his residence); a few wizards together could clean Hogwarts.


I can't find the bin folder in my .minecraft folder!

I am trying to get mods on my minecraft but the folder isn't there and so I can't get to my minecraft.jar folder... and I even looked in the version folder where someone told me the bin folder would be and it wasn't there. is there any way to get the bin folder so I can get to the minecraft.jar folder?


Include h-file with definitions inside in multiple cpp-files

My problem is that I have header-file (custom unit-test framework) with function definitions in it. For example: unit_test.h: #pragma once ...     void Assert(bool b, const string& hint = {}) {     AssertEqual(b, true, hint); } ...  it's convenient for me to keep some functions defined right in the header, because I often use this functional by simply including (unit_test.h is located in separate directory C:/Dev/include). But if I am dealing with a project where multiple cpp files use this functionality, I get a multiple definition error as expected. Simple project looks like: main.cpp: #include "unit_test.h"  void foo();  int main() {     Assert(1);     foo();     return 0; }  foo.cpp: #include "unit_test.h"  void foo() {     Assert(2); }  So I want to know if there is a right way to keep function definitions in a header file and use it in project without getting an multiple definition error? (Or would it be better to move the function definitions to the source and compile it separately each time, or compile unit_test into a static library?)


XSession errors filling up my disk space

I have a Ubuntu 16.04.1 installed on my NUC.   After I reboot, I can see .xsession-errors increasing in size rapidly. The below is after 2 minutes.  -rw-------  1 kodi kodi 3466402072 Jan 20 18:49 .xsession-errors -rw-------  1 kodi kodi 6548127878 Jan 20 18:46 .xsession-errors.old   Running a tail -f on the file gives me nothing but continious output of:  extern "Python": function Cryptography_rand_bytes() called, but @ffi.def_extern() was not called in the current subinterpreter.  Returning 0.


and     The first one look like $\xi$ but not completely the same.


applying clipping mask to multiple objects

I want to apply a brush splash to the central petals of the flower. But clipping mask doesn't work. It says object is too complex. The only way I found to resolve this problem is using shape builder tool and cut every single petal in order to avoid outlines overlapping.  Then make a copy of petals with fill and place a brush splash between outlines and fill layer. I wonder is there any less time consuming solution ? The main problem is outlines, they overlapping each other without a fill. Opacity mask doesn't adress my problem, because I don't want the outlines to be covered by a brush splash. The brush splash have to be inside of each petal. Thank you !


Connection flight to domestic flight at Ataturk airport

I am traveling from Oslo, Norway next week to Gazipasa in Turkey, but there is no direct flight so  I will land in Ataturk airport with  1hour and 15min time before my next flight to gazaipasa.  Is that enough time to get through passport/visa control and change to the domestic terminal ?


How to get tack sharp portraits with shallow DOF when lacking an AF point where I want to focus?

What is the best way to get tack sharp portraits with shallow depth of field when lacking an auto focus point where I want to focus. I don't want to crop and "focus and recompose" is not an option since the shallow depth of field will throw the person out of focus. Of course a precise measurement of the distance is possible, but also very cumbersome and to do manual focus is a bit of a guessing game. Any ideas or do I have to relax my requisites?


Lightning Web Components - Are there analogues to Angular Expressions?

I have just started using LWC recently having normally coded front-ends in Angular of some sort. There are a couple of things that you don't seem to be able to do with LWC that seem to be really bloating my code, but I wondering if I'm just haven't come across the right way of doing things.  Objects can't be tracked  I'm used to getting a record from the server and assigning it to a single property in the component class, and then referring to a property of that object from the template, e.g.:  <my-component [some-attribute]="myModel.property"></my-component>   Whereas with LWCs, a separate tracked property needs to be created for each property of the model used on the template, and then transformed back into a single object on save etc. It seems very long-winded for scenarios with lots of properties.  There are no expressions  I've found that using template expressions in Angular is very handy way to cut down on code because a single property in the component class can be referenced in different ways, e.g.  <input name="account-name" [required]="stagePercentage >= 50" /> <input name="account-postcode [required]="stagePercentage >= 80" />   whereas for the same scenario with LWCs, two handler functions would have to be written in the controller:  <lightning-input required={stagePercentage50OrMore} /> <lightning-input required={stagePercentage80OrMore} />   and that is just a very simple scenario.  Have I missed any obvious patterns or ways of approaching this? Are there ways I could be reducing code here?  Thanks


After reading this question , I want to know the answer of the following.  When should we use \begin{center} instead of \centering?  For example, should we use this one?  {% \centering <other contents> }   or this one?  \begin{center} <other contents> \end{center}


Understanding the concept of surface tension

The concept of surface tension doesn't seem to be well explained in the first course on Fluid Mechanics. Fundamentals of Fluid Mechanics writes      A tensile force may be considered to be acting in the plane of the surface along any line in the surface. The intensity of the molecular attraction per unit length along any line in the surface is called the Surface Tenison .    There are a few things that are causing me problems:     The analogy tensile force is quite hard to understand, I mean the force of attraction looks something like this . As you can see, the molecules at the top have no upward force acting on them and therefore they form something like a surface (this what others writes). Well, okay there is no upward force but we can certainly go for superposition of forces and from the diagram, we can see that the upper molecule should accelerate downwards but it doesn't, why? How all this have any correlation with tension? (the way I have understood tension till now is the force that a string exerts on an object connected to it).   The phrase along any line in the surface is causing problems because it writes in the surface not on on the surface which is quite hard to comprehend what the book intends.     I request you to please explain the concept of Surface Tension considering the problems that have written over here. If you present your personal understanding of the topic then it will be much appreciated.    Thank you.    EDIT: The concept of surface tension is causing me problem because what I’m thinking of surface tension is something like a stretched bed sheet on which things kept do not fall, but the problem is how this bed sheet analogy has arrived in fluids, I mean at the surface molecules and the mathematical definition of surface tension doesn’t make sense to me.


I keep on getting a null pointer exception when i am trying to update.I had tried toasting the values and its not null at all. Im stuck in here, any help would be great.  01-05 01:50:20.082 31956-31956/org.gandroid.motif E/AndroidRuntime: FATAL EXCEPTION: main                                                                     Process: org.gandroid.motif, PID: 31956                                                                     java.lang.NullPointerException                                                                         at org.gandroid.motif.Secondwcscreen$1.onClick(Secondwcscreen.java:218)                                                                         at android.view.View.performClick(View.java:4463)                                                                         at android.view.View$PerformClick.run(View.java:18770)                                                                         at android.os.Handler.handleCallback(Handler.java:808)                                                                         at android.os.Handler.dispatchMessage(Handler.java:103)                                                                         at android.os.Looper.loop(Looper.java:193)                                                                         at android.app.ActivityThread.main(ActivityThread.java:5292)                                                                         at java.lang.reflect.Method.invokeNative(Native Method)                                                                         at java.lang.reflect.Method.invoke(Method.java:515)                                                                         at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:824)                                                                         at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:640)                                                                         at dalvik.system.NativeStart.main(Native Method)   This is the error i get when i tried updating.  Bundle b = getIntent().getExtras();                             getLastperiod = b.getString("LP");                             Date inputdate = sdf.parse(inputlastperiod);                              Date getprevdate = sdf.parse(getLastperiod);                             newcal.setTime(getprevdate);                              String prevperiod = sdf.format(newcal.getTime());                             String newperiod = sdf.format(inputdate);                               Date PP = null;                             Date NP = null;                             Integer daysbetween = 0;                             try {                                 PP = format.parse(prevperiod);                                 NP = format.parse(newperiod);                             } catch (Exception e) {                                 e.printStackTrace();                             }                              DateTime valPP = new DateTime(PP);                             DateTime valNP = new DateTime(NP);                              daysbetween = Days.daysBetween(valPP, valNP).getDays();                             String newPeriodrange=daysbetween.toString();                             Integer id = 1;                                if (newPeriodrange!=null) {                                myDB.updatePeriodrange(newPeriodrange,id);                             }   This is where my update statement lies.  public void updatePeriodrange(String newcyclerange,int id){         SQLiteDatabase dbase = this.getWritableDatabase();         String query = "UPDATE userinfo SET PERIODRANGE= "+newcyclerange+" WHERE ID='"+id+"'";          dbase.execSQL(query);     }   Then this is my databasehelper class.


Is it possible to show (pop-up) a message box with an input field in it, possibly a text box? Is somewhere in the language or the framework?


Buying game collection that contains game that I own Steam

Let's say I buy a game. And after a few months, the bundle that contains the game (e.g. all games from specific publisher or developer or franchise) go on sale and I wish to buy that bundle. What happens to that game? is it removed from the bundle and I not pay for it? Do I get charged twice? Do I get the game as a gift?


Is there a word for occurring four times a week?

I am trying to use this word to say how often my basketball team meets to practice.


Supervisor delays publication over style questions for years – can I remove him from the authors list?

I did my PhD four years back. I was funded from my home country and I have done all the work. I started writing papers before submitting my thesis.  I am sending my supervisor drafts every year until now. Altogether I have now done 32 drafts. Since last year alone, I have rewritten my paper 12 times but he still is not happy to submit it and not willing to make any changes by himself. He is even not letting me to show it to the reviewers.  My supervisor is a lecturer and I was his first PhD student. I acquired the opinion of two professors (one of them is my 2nd supervisor and is a co-author) recently about the quaility of paper and they recommended to send it to a good journal (impact factor of 10 and above). After many years of struggle my supervisor wished to publish it in a journal with an impact factor less than 1. Above all he is not willing to pay publication costs and he is not allowing me to try for good journal. I am the one who did all the work, who paid for work, who wrote paper and who is paying for publication costs and i am not allowed to try any good journal.  One thing about his recomened changes: He did not ask repeating any experiments, redoing any analysis or revisiting any conclusions. It’s only text style that is being changed over last four years.  I contacted the university services and they told me that I don’t qualify for university help as they only cover two years post PhD duration.   What can I do now? Can I publish my work without him as co author. Can I just acknowlege him for hosting me and remove his name from the author list?


Can I adapt a Sigma SLR lens made for Pentax K mount to a Nikon DSLR camera?

I now have a Nikon D3200 and the lens is not great.  Can I adapt my Sigma Aspherical IF 28-300mm zoom lens, which I'm currently using on a Pentax MZ-30?


What are the differences between the Baum-Welch algorithm and Viterbi training?

I am currently using Viterbi training for an image segmentation problem.   I wanted to know what the advantages/disadvantages are of using the Baum-Welch algorithm instead of Viterbi training.


I have a cube, and I would like it to have a text inscribed in it, so the text would be in the cube but we could see it. Is it possible to do this?


(In 2013) I don't know why Python is that weird, you can't find this by searching in google very easily, but it's quite simple.  How can I detect 'SPACE' or actually any key? How can I do this:  print('You pressed %s' % key)   This should be included in python core, so please do not link modules not related for core python.


How to give an image or video a TV screen effect?

I thought it would be interesting to create a .blend that filters any regular video or image with vintage television look.   Edit: Although this question initially arose from my desire to create a vintage look, it has since been pointed out in a comment that all displays use arrays of RGB emitters, so it's not really an issue of vintage or not. How vintage it will end up looking is probably more a matter of the shape, size, and density of the emitters.  Reference images:       Upon examining the structure of screens, the most common seems to be rows of vertical RGB bars:    Here is another type which I believe is common in computer displays - circular dots in a hexagonal grid:    I have been thinking about how to make a screen in Blender that takes its input from an image or image sequence and for each frame converts the RGB value for a pixel (or region) and uses that to illuminate the red green and blue phosphors in the correct ratios so that when viewed from a distance an image is distinguishable.  Do you think this will require python scripting? I made some initial attempts modeling an array of phosphors then using a Light Path node and a Separate RGB node in Cycles but I haven't gotten very far. I would love to hear what you all can suggest.  Thanks!


Convert file contents to lowercase and store result in same file

I use the following command to convert my input file contents to lowercase  tr A-Z a-z < input > output    This command works fine.  But when I try to store the output in input file itself, it is not working. The input file is empty after executing the command. Why?   tr A-Z a-z < input > input


I am fairly new to Meta.     I don't know why i am not able to make a comment even though my comment length is more than 15 character.


Algorithm to determine if array contains n...n+m?

I saw this question on Reddit, and there were no positive solutions presented, and I thought it would be a perfect question to ask here. This was in a thread about interview questions:  Write a method that takes an int array of size m, and returns (True/False) if the array consists of the numbers n...n+m-1, all numbers in that range and only numbers in that range. The array is not guaranteed to be sorted. (For instance, {2,3,4} would return true. {1,3,1} would return false, {1,2,4} would return false. The problem I had with this one is that my interviewer kept asking me to optimize (faster O(n), less memory, etc), to the point where he claimed you could do it in one pass of the array using a constant amount of memory. Never figured that one out.  Along with your solutions please indicate if they assume that the array contains unique items. Also indicate if your solution assumes the sequence starts at 1. (I've modified the question slightly to allow cases where it goes 2, 3, 4...) edit: I am now of the opinion that there does not exist a linear in time and constant in space algorithm that handles duplicates. Can anyone verify this? The duplicate problem boils down to testing to see if the array contains duplicates in O(n) time, O(1) space. If this can be done you can simply test first and if there are no duplicates run the algorithms posted. So can you test for dupes in O(n) time O(1) space?


Sentence 1： I was told my work was unsatisfactory, at which point I submitted my resignation.  Sentence 2：Sometimes you may feel too frail to cope with things, in which case do them as soon as it is convenient.  I am confused with "which" in the above two sentences. Does it serve relative determiner, rather than relative pronoun? Does "which point" in the first sentence stand for "I was told my work was unsatisfactory"?Does "which case" in the second sentence stand for "sometimes you may feel too frail to cope with things"?  Thank you in advance!


I have seen someone putting a sandstone in water. With only about 10% of the stone sitting in the water. One could see the stone getting soaked with water. So there must be a force, which lets the water climb up through the stone against gravity.  What is that force? Or is there some other effect present?


Is there any Mathematical explanation why derivatives are way easier than integrals?

Integrals and derivated are related as an indefinite integral is an anti-derivative, however, I found it always perplexing that derivatives can be always found easily (well, at least the ones I saw during the past years) and there are so many ways to set a very challenging integral or even one that can't be solved at all (example when the integrand is $e^{x^2}$), is there any mathematical explanation behind this or it is just a "that is how things are" type of thing? I tried going back to the definition of both and couldn't find anything helpful.


Multiple user accounts from same client on network share?

My Win7 professional client has a connected network drive to the server with cached login (user/pw) data. How can I connect to the same server as a different user simultaneously?


How do I remove all traces of Git for my repository?

I have a repository.  ("git init")  I've done check-ins and commits and logs and stuff. But, how can I remove all traces of git and delete git off this directory (and subdirectories)?   I'm on Ubuntu.


How to detect if a USB port is 3.0 or 2.0?

I have a  external HDD. It has USB 3.0. It flashes blue if you connect it to a USB 3.0 port. If it is a 2.0 port, the light becomes white.  Yesterday, I plugged it in and the light was blue. Now, I plugged it in the same port and the light is white.  Can I somehow detect if the USB port I just plugged in is 2.0 or 3.0? I want to know if there is a problem with the device or the USB port I'm using.  Edit: I'm using Windows 8.1


Where does the energy go if a ball hits the ground WITHOUT bouncing?

so if a very un-bouncy object hits the floor and crashes into it rather than bouncing, where does most of the energy go? Does it simply turn into heat from friction? Or does it go into the Earth's movement by an imperceptible amount?


What does public home() do in a c# winform?

I was wondering what this part of a c# winform does. public home() {     InitializeComponent(); }


What is the right way to remove that symbolic link in Ubuntu 15.10?

I've created this link:  sudo ln -s /etc/phpmyadmin/apache.conf /etc/apache2/conf-enabled/phpmyadmin.conf   I've tried to remove it in these ways:  sudo unlink /etc/phpmyadmin/apache.conf /etc/apache2/conf-enabled/phpmyadmin.conf sudo rm ln /etc/phpmyadmin/apache.conf /etc/apache2/conf-enabled/phpmyadmin.conf sudo rm ln -s /etc/phpmyadmin/apache.conf /etc/apache2/conf-enabled/phpmyadmin.conf   These three ways didn't work for me. What have I missed?


Can I go to Austria directly from India with Hungarian residence permit?

I have a residence permit to stay in Hungary. So I was on holiday in India and now want to go back to Hungary. But I have to attend a concert in Vienna in September so I am thinking of going to Vienna directly from Delhi instead of going to Budapest then to Vienna.  So is it ok  to book flight to Vienna with a residence permit of Hungary? Or do I need to book flight for Budapest from India?


How to populate values in a cell from different table, separated by comma

I have six tables  a. Employee  EmployeeId         EmployeeName 123                John 125                Peter 129                Jack   b. EmployeeParameterValue  EmployeeParameterValueId         EmployeeId    ParameterValueId 1                                123           1 2                                125           2 3                                129           3   c. ParameterValue  ParameterValueId    ParameterId    Value 1                   2              1, 2, 3 2                   3              1, 2 3                   2              3   d. Parameter  ParameterId      Name 2                WorkedStates 3                WorkedType   e. WorkedStates  WorkedStatesId    WorkedStatesName 1                 CA 2                 WA 3                 NY   f. WorkedType  WorkedTypeId          WorkedTypeName 1                     Hourly 2                     Salaried   I need to write a report in following format:  EmployeeId         EmployeeName       Parameter          ParameterValue 123                John               WorkedStates       CA, WA, NY 125                Peter              WorkedType         Hourly, Salaried 129                Jack               WorkedStates       NY   I am able to write a query which fetches first 3 columns. But I am not able to write a query which fetches the data in the fourth column.  Please advise.


Hide the flag count if I've already handled them all

Since Aviation is in beta, I got access to the 10k tools at 2k. I've already handled the one flag, but the [1] persists on every page I browse to, hereafter.  Can the flag count be updated to only show the number of flags I haven't handled? (i.e. remove it at 0)


What happens when a "matter-black-hole" and an "anti-matter-black-hole" collide?

Let's say we have one black hole that formed through the collapse of hydrogen gas and another that formed through the collapse of anti-hydrogen gas. What happens when they collide? Do they (1) coalesce into a single black hole or do they (2) "annihilate" into radiation?  One would expect (1) to be the case if the No Hair Theorem were to hold. So I guess what I'm really asking for is a modern understanding of this theorem and its applicability given what we know today.


Why do some page contain a rough sketch?

First of all, I have to say I read this on some scanlated site. But there are quite a few page that look unfinished.  Here are some of the rough page I found. Top pictures, From Historie 80 and 94. Bottom Pictures, Historie 82, 96, and 97. (Click to enlarge pictures)     Noticed that . If they want a shadow building they can do it better.  At first all panel are finished but later, probably after chapter 80, they begin having unfinished drawing. Hitoshi Iwaaki other manga series  doesn't have this kind of drawing style.


What is it called when someone hates disabled people?

I’m having an argument with someone else who keeps telling me that racism is hating any kind of person. He keeps telling me that racism is sexism, etc.   I just want to know what the term for a person that hates disabled people (like mentally or physically disabled people) would be so I can prove him wrong. I know that’s a little ridiculous, but whatever.


Why is it a good idea in measure theory to define $0\times\infty=0$?

Reading about measure theory has led me to consider extended real numbers. I have read that in this context $0\times\infty$ is defined as $0$. The wiki article  supports this claim.   Of course, I am familiar with the usual thing said in calculus courses that $0\times\infty$ is not a well defined thing (or better said, products of functions with zero and infinity as limits can have as a limit zero, infinity or any other real number).  In any case, I am interested in knowing why in the context of measure theory it is a good idea to define $0\times\infty=0$. What is the motivation?


Solve the difference equation $x_n-4x_{n-1}+3x_{n-2}=0$, $x_0 = 2$, $x_1 = 5$

Solve the following difference equation to the specific $x$ values  $x_0 = 2$ $x_1 = 5$ $x_n-4x_{n-1}+3x_{n-2}=0$   I need some help and guidance to get this problem started and to understand the proper way to solve these equations.


I need to uninstall ubuntu but i cant find how to for my situation. I have ubuntu and windows xp both installed on my computer. However, the windows xp came preinstalled so i dont have the cd. I do not have a dvd/cd drive on my computer (I installed ubuntu via usb). Is there any way i could uninstall ubuntu while keeping xp installed.


Can I have multiple Xcode versions installed?

Is it possible to have more than one version of Xcode installed at the same time?   If so, please post any tip, tricks, or potential issues to watch out for.  EDIT:  The reason I want to install multiple versions is to try out the new sdk beta, but if the new Xcode is buggy I want to be able to use the older version for my existing projects.


I wanted to know what's a .desktop file and how can I generate one in order to have a Wine application displayed on my Launcher bar on the left. Now I have to open the folder where I store the executable and open it with Wine, and that's too slow.  I have done some research and I saw some questions related to this already answered (). They say we can generate it, but I don't understand how  Thank you very much in advance! I am a novice to Linux, and I am using 12.04.


How to enable syntax highlighting features in vi editor ? I am currently using ubuntu 16.10.  Here is the output of vi --version.   VIM - Vi IMproved 7.4 (2013 Aug 10, compiled Nov 24 2016 22:32:42) Included patches: 1-1829 Extra patches: 8.0.0056 Modified by pkg-vim-maintainers@lists.alioth.debian.org Compiled by pkg-vim-maintainers@lists.alioth.debian.org Small version without GUI.  Features included (+) or not (-): +acl             -farsi           -mouse_sgr       -tag_any_white -arabic          -file_in_path    -mouse_sysmouse  -tcl -autocmd         -find_in_path    -mouse_urxvt     -termguicolors -balloon_eval    -float           -mouse_xterm     +terminfo -browse          -folding         +multi_byte      -termresponse +builtin_terms   -footer          -multi_lang      -textobjects -byte_offset     +fork()          -mzscheme        -timers -channel         -gettext         -netbeans_intg   -title -cindent         -hangul_input    +packages        -toolbar -clientserver    +iconv           -path_extra      -user_commands -clipboard       -insert_expand   -perl            +vertsplit -cmdline_compl   -job             -persistent_undo -virtualedit +cmdline_hist    +jumplist        -printer         +visual -cmdline_info    -keymap          -profile         -visualextra -comments        -langmap         -python          -viminfo -conceal         -libcall         -python3         -vreplace -cryptv          -linebreak       -quickfix        +wildignore -cscope          -lispindent      -reltime         -wildmenu -cursorbind      -listcmds        -rightleft       +windows -cursorshape     -localmap        -ruby            +writebackup -dialog          -lua             -scrollbind      -X11 -diff            -menu            -signs           +xfontset -digraphs        -mksession       -smartindent     -xim -dnd             -modify_fname    -startuptime     -xsmp -ebcdic          -mouse           -statusline      -xterm_clipboard -emacs_tags      -mouse_dec       -sun_workshop    -xterm_save -eval            -mouse_gpm       -syntax          -xpm +ex_extra        -mouse_jsbterm   -tag_binary       -extra_search    -mouse_netterm   -tag_old_static      system vimrc file: "$VIM/vimrc"      user vimrc file: "$HOME/.vimrc"  2nd user vimrc file: "~/.vim/vimrc"       user exrc file: "$HOME/.exrc"   fall-back for $VIM: "/usr/share/vim" Compilation: gcc -c -I. -Iproto -DHAVE_CONFIG_H   -Wdate-time  -g -O2 -fdebug-prefix-map=/build/vim-vY1bx1/vim-7.4.1829=. -fPIE -fstack-protector-strong -Wformat -Werror=format-security -DTINY_VIMRC -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1       Linking: gcc   -Wl,-Bsymbolic-functions -fPIE -pie -Wl,-z,relro -Wl,-z,now -Wl,--as-needed -o vim    -lSM -lICE -lXpm -lXt -lX11 -lXdmcp -lSM -lICE  -lm -ltinfo  -lselinux -lacl -lattr -ldl    I have tried :syntax on. Below is the error message of :syntax on  E319: Sorry, the command is not available in this version


View remote value of $PATH inside shell script

When executing this bash script, it only shows my local path.  ssh ${REMOTE_HOST} 'bash -s' <<EOL     set -e     source ~/.profile     echo $PATH     # Commands here don't work because $PATH is not set properly.     # How can I see what $PATH is set to here? EOL   How can I view the remote value of $PATH to debug this?


Let's say we are given a closed race track with a given and constant width. I am to implement an algorithm which finds both shortest path trajectory and minimum curvature trajectory for the car.   I have found a paper  which explains both the shortest path trajectory and the  minimum curvature trajectory.  I understood the shortest path equations except (8) but couldn't understand any equations in the minimum curvature path trajectory. Could someone please explain those equations?


Does light reflect if incident at exactly the critical angle?

A lot of textbooks and exam boards claim that light incident at exactly the critical angle is transmitted along the media boundary (i.e. at right-angles to the normal), but this seems to violate the principle of reversibility in classical physics.  How would a photon or ray travelling in the reverse direction "know" when to enter the higher refracting medium?  It can't know, so I conclude that such light is simply reflected?  Is this correct?


Prove that there are uncountably many surjective functions f : N → N

Can you help me determine what I am doing wrong in this proof? Is this sufficient?


If we have a single frequency of light, then the energy associated with that light ray can be given as: $$ E = h \nu$$ However, white light is a mixture of different frequencies of light in 'some' proportions, so how do we assign an energy for white light?


How do I avoid users hacking my network games from the client side?

I've decided to make an online game; the server sends packets of information to the client application, which is going to simulate what it gets from the server. The client makes a part of the design of the game, and sends the new state back to the server for processing.  The clients can send fake information to the server, and inform the server that I've done the task successfully, without trying. Assume a Counter-Strike game; the client may send a fake packet to the server and tell the server that I've defeated someone. How can I avoid this violation?


Can I install Android on my non-Android device?

Many people want to try/use Android without buying a new Android phone.  How can I install Android on my current phone or device running Nokia Symbian, Maemo, or MeeGo; Microsoft Windows Mobile or Windows Phone 7/8/10; Apple iOS (iPhone); RIM's BlackBerry OS; Palm's WebOS; Samsung's Bada; HP's WebOS; Mozilla's Firefox OS; or other phone / operating system?


I would like to position three subfigures like this:  (a) (b) (a) (c)   Figure (a) on the first roll and figures (b) and (c) on the second. Some light, please?  Thanks in advance.


Subscriber Key related to Multiple Emails

Can someone help clarify use case where we should have Subscriber key related to multiple email addresses?   We generate our own subscriber key but we want to give a Subscriber opportunity to be communicated to different email addresses (what he wants to receive on what email) but we still want to track him through 1 Subscriber key.   How should we approach to this scenario? Possible solutions?


The title pretty much sums it up.  I would like to send UDP traffic through a SSH tunnel.  Specifically, I need to be able to send UDP packets through the tunnel and have the server be able to send them back to me on the other side.  I know how to do it for TCP connections. Is this it possible with UDP?


How to make a minecraft server which works for multiple versions

I found out that making a server doesn't work for me , and I've seen servers which support multiple versions at once, so players can connect using a wide range of Minecraft versions. How do i do that on my own server?  (I'm looking specifically for help with 1.8 to 1.12.2)


UNLINK does not work to convert particles into new/original meshes

I am converting a particle system (based on a collection of meshes) into new meshes.   The 'new' meshes stay connected (as I can see in EDIT mode) to the original one. Setting every single mesh to an 'original' mesh in the object tab takes a lot of time.   This question...  ...seems to be the same, but the answer which is UNLINK(ING) the object(s) by pressing 'U' makes everything disappear as if I am hitting a delete button instead of 'unlink'.  Does anybody know what I am doing wrong?


Did Voldemort die or stay in limbo after the final battle?

In Harry Potter and the Deathly Hallows, while Harry is in Kings Cross he sees something like a small child, which is the fragment of Voldemort's soul that was attached to him.     He recoiled. He had spotted the thing that was making the noise. It had   the form of a small, naked child, curled on the ground, its skin raw and rough, flayed-looking, and it lay shuddering under a seat where it had been left, unwanted, stuffed out of sight, struggling for breath.      He was afraid of it. Small and fragile and wounded though it was, he did not want to approach it. Nevertheless he drew slowly nearer, ready to jump back at any moment. Soon he stood near enough to touch it, yet he could not bring himself to do it. He felt like a coward. He ought to comfort it, but it repulsed him.      Harry Potter and The Deathly Hallows   Once Harry returns to the world of the living, that part of Voldemort's soul stays in limbo. Is this what happens to all fragments of someone's soul if he has divided his soul by creating a Horcrux? Does that mean that Voldemort's soul however crippled will stay in limbo or when all parts of his soul die, so does he?


Where are the ATP synthases synthesised?

The nano-machinary of energy production ATP synthase is well known to exist on mitochondrial inner membrane and chloroplasts. But how and where are they formed or synthesised ?


Related, but no longer reproducible:   Background  I  on Stack Overflow, when I noticed that none of the links in the "about me" section and also the link to a custom page (the one with the chain icon on the right side) worked. I guessed that this was due to the new users limitations, which are removed after you reach 10 rep.   Also see  and this  from chat for more context on the problem I had.  But  (thanks for digging the FAQ out) found out that the  and the  both state that:     [New users can't] post more than eight hyperlinks at a time, either in a post or their user profile.   How it looks, this has been reduced or completely disabled in the meantime. Anyway, the FAQ on meta.SE, SO and very likely all other sites should be updated to state correct information.  EDIT: Please note that the question isn't about the network profile page, I understand that links are disabled there (See the comments). The problem relies in the FAQ/the site-specific profile. The reason posting that here and not on meta.SO is that this problem likely relies also on other sites.


What's the canonicity of Lucas's former "word-of-God" statements?

In the past, many names, objects and ideas in the Star Wars universe were canon merely because Lucas said so, particularly somewhere in an interview (i.e., never appeared in the films, scripts, production notes or even novels).  As  states, Lucas was "word of God" but now Disney owns the franchise and dictates canon.  The idea I'm particularly curious about is the meaning "bring[ing] balance to the Force."  (the natural state of the Force is the Light Side and the Sith are destroyed) while the , being completely ambiguous. Are we to take Wookieepedia at face value, or has anyone at Disney or the LSG chimed in?


Relation between line bundles over $\mathbb{P}^1$ in geometry and topology

For an algebraic geometry assignment I recently had to prove that the isomorphism classes of line bundles over $\mathbb{P}_k^n$ for any field $k$ are the powers of the tautological line bundle, or in other words the Picard group is given by Pic($\mathbb{P}_k^n) \cong \mathbb{Z}$.  I was trying to consider simple examples to reconcile this with my intuition about line bundles from algebraic topology.  Taking $k = \mathbb{R}$ and $n = 1$, we have Pic($\mathbb{RP}^1) \cong \mathbb{Z}$.  Naively, I might have thought that since $\mathbb{RP}^1 \cong S^1$, there would be only the two isomorphism classes of (topological) line bundles over the circle.  I was wondering: what are the relations between line bundles in algebraic geometry and topology in this case, and why the discrepancy?    I figure maybe the real numbers are not a very well behaved field in algebraic geometry. If $k = \mathbb{C}$ and we again take $n = 1$, do the classifications of bundles match up on $\mathbb{CP}^1 \cong S^2$ in the geometric and topological contexts?


Would it matter if the Earth rotated clockwise?

In the Futurama episode "" they save the world by rotating the Earth backwards saying it shouldn't matter (which direction Earth rotates). If Earth rotated clockwise and remained in it's current counter-clockwise orbit around the Sun, would it affect anything beyond the direction the constellations move across the sky?


How does relativity explains time-dependent behaviour for objects not experiencing time?

A variable electrical field produces a variable magnetic field, which in turn produces a variable electrical field, and so on, leading to an electro-magnetic wave, which is eventually what light is all about. "Variable" means "variable with respect to time". This is my understanding of light from classical physics. However, relativity tells us that whatever travels at the speed of light does not "experience" time, i.e. its 4-dimensional space-time velocity vector has no "time" component (the object travels only through space, not through time). How does this blend with the classical physics definition of electromagnetic wave? How can a "variation with respect to time" occur if the object does not experience time at all?


How do I open a text file in my terminal?

There is a file named RESULTS.txt and I want to open this file in my terminal. (I mean I want to see the file contents be displayed in the terminal and not in some text editor)   How do I do that ?


A local user can start x0vncserver. An ssh user not

Enviroment is Lubuntu 20.04 x86-64 with LXQT desktop manager. I am logged in in the LXQT as 'zoe' and I run the command x0tigervncserver --rfbauth=/home/zoe/.vnc/passwd which works and I can connect from another PC. Now I stop the x0tigervncserver with control-c. I remain loggen in in the LXQT. I logged in also with ssh from another PC and run exactly the same command. Now it says x0tigervncserver: unable to open display "" Exactly the same error displays when I create a systemd service for x0tigervncserver and run systemctl enable/start/status. All of them (enable/start/status) with loaded LXQT and user logged in. It seems that when run the command from ssh console or when run the command with systemd, X is not available for some reason, so it cannot found display "". But X is loaded because LXQT is loaded. What I miss here?


Reusing a method to pass text string and voice input but getting NullExceptionPointer and can't figure it out

I'm running Spinx voice recognition as a thread and want to pass the result to a bot method mirroring the same method in Main to pass text. However keep running into NullPointerExpection and can't reason it out or overcome it. Why does it work in Main but not in Reply class.   the text send button in Main is:  private void onSend(java.awt.event.ActionEvent evt) {                                 // display users message         txtHistory.setText(txtHistory.getText() + "\nYou: " + txtMessage.getText() + "\n");          //send the input to the bot and get bot response         String response = bot.send(txtMessage.getText());          //if the response is not empty show it         if (response.length() > 0) {         addBotText(response);         }            //display new state message to continue         addBotText(bot.getMessage());             //clear the input message box        txtMessage.setText("");    }   In the Runnable (Threaded) Spinx Reply class i have a method to get the voice input and then show it as a string:      private void start_recognition(Result result) {              if (result != null) {                 String resultText = result.getBestFinalResultNoFiller();                 //send the message to the bot                 String response = bot.send(resultText);                 System.out.println("You said: " + resultText + '\n');             } else {                 System.out.println("I can't hear what you said.\n");         }    }   (With private Bot bot; commented above in both Main and Reply) When I comment the String response = bot.send(resultText); out all is well, but trying to invoke the bot.send method creates a nullPointerException. I realize I'm doing something incredibly stupid but can't figure it out. The Bot method is below. Any help greatly appreciated.  In Bot class the send method:     public String send(String message) {      String response = "";     State state = parser.getState(level);      // end of the tree     if (state.getKeywords().isEmpty()) {         this.level = "1";     }      // match the keyword with given message     Keyword match = parse(message, state.getKeywords());      // if no keyword is matched, display one of the invalid answers     if (match == null) {         response = parser.getInvalidAnswer();     } else {          // if match classname is provided, check to get the dynamic response         if (match.className.length() > 0) {              // check for Weather dynamic response             if (match.className.equals("Weather")) {                 Weather weather = new Weather();                 response = weather.getResponse(match.arg);                 this.level = "1";             }             // check for News dynamic response             if (match.className.equals("News")) {                 News news = new News();                 response = news.getResponse(match.arg);                 this.level = "1";             }         } else {              // get the new state and return the new message             if (response.length() == 0) {                  this.level = match.target;                 state = parser.getState(level);                  // if it is end of the tree                 if (state.getKeywords().isEmpty()) {                     response = this.getMessage();                     this.level = "1";                  }             }         }     }     return response; }   All code for the conditional bot is credited to Majid Khosravi


Generating power with a "straw" to space... Is it possible?

Imagine you have a straw in a glass of water. If you put a turbine inside it somehow and move the glass, pour water in and out of it etc, you would see the water level rise and fall, and the turbine would spin, generating power.  I'm sure you can see where I'm going with this:   Our atmosphere far from a static glass of water, there are colder and hotter parts that create air flows, that can be very fast, and could output a lot of energy. So is it possible/feasible to generate energy this way; by placing turbines in a long straw from Earth to space? I know it may not be practical, but is it physically possible?  Similar methods are already being used to harness energy from ocean waves, so i wondered if this would be possible as well.


What part of the cylinder displaces some volume from the second liquid (which is used for the buoyant force)?

Consider a container filled with two liquids, of densities $\rho_1$ and $\rho_2$, such that $\rho_2 < \rho_1$. Now imagine placing a cylinder with the top base removed, of density $\rho,\space \rho_2<\rho<\rho_1$, such that the cylinder floats between the liquids. The second liquid is barely filling the cylinder, whose interior diameter is $l_1$ and whose exterior diameter is $l_2$. An illustration can be found below:    Now I am a little bit confused about the buoyancy force in liquid $2$: I thought I could express it as (assuming the height of the cylinder in liquid $2$ is $h$):  $$F_{B2} = (S_2-S_1)h\rho_2g=(\pi\frac{l_2^2}{4}-\pi\frac{l_1^2}{4})h\rho_2g=\\=\frac{\pi h\rho_2g}{4}(l_2^2-l_1^2)$$  Because the liquid actually enters the cylinder and only the walls displace a volume of liquid. However, the authors of the problem and my teacher claim that:  $$F_{B2}=\frac{\pi l_2^2h\rho_2g}{4}$$  Which means that the entire part of the cylinder that lies in liquid $2$ actually displaces a certain part of its volume, rather than the walls only. I have strong reasons to believe that I am wrong, because this is a tiny sub-part of a problem from a national contest, and the official solutions claim that the latter is correct. Which version is correct and why? What part of the cylinder displaces some of the second liquid, the walls or the cylinder itself as a whole (well, the part of them that lie in the second liquid) and why?


I saw last week a presentation that was made with keynote and which was showing cells filled with speckled colours. Is there a way to get speckled colours in latex/beamer ? Until now I was only able to find uniform fills.  greetings, yves  SAM: I would like to see some granularity in my fill:


While I was on Music meta recently, a +5 popped into my achievements box.  I clicked on my notification box, and this is what I saw:    Notice that the badge I got on Literature.SE has a "Note" badge beside it.  Shouldn't it be the generic dot, even though I am on the Music stack?


If $p$ is a polynomial, then either $\,p(z)=z^n\,$ or $\,\max_{|z|=1}|p(z)|>1$.

Let $p(z)=z^{n}+a_{n-1}z^{n-1}+...+a_{0}$ be a polynomial of degree $n\geq1$.  How can you prove that either $p(z)=z^{n}$ or there exists $z'$ with $|z'|=1$ such that $|p(z')|>1$.  Maybe we can use the maximum modulus principle and consider $q(z)=z^{n}p(1/z)$.


Is a horcrux made everytime someone kills?

I want to say the answer is "no", because Voldemort probably killed way more people than the amount of horcruxes he has and not every evil murderer wants to make horcruxes.  Also it seems to be a complex process, given that Tom Riddle asks Slughorn about it. It requires an evil act (like murder), but it seems to be more to it.  But, Harry was a horcrux Voldemort never wanted and not really knew about.   Can one accidentally make a horcrux?


Why does trying to run a python executable return ': No such file or directory' after transferring it to server via FTP?

I'm having an issue where when I transfer a Python file to my VPS via FTP and try to run it using ./foo.py I am returned with the error: : No such file or directory.  The error seems to indicate that the file I am trying to execute does not exist. But I can run the program with no problems using python foo.py which leads me to believe that the error actually probably means something else.  At first I thought it could be an issue with the shebang line, so I copied all of the content of the file and pasted it into a new file on the VPS that had not been transferred via FTP. The two files had exactly the same content but when I ran the new file using ./bar.py it ran as expected.  So I've come to the conclusion that this could be an issue with the way that it is transferred. I have switched between ASCII and binary but both of these transfer methods give the same error.  Is it possible to stop this from happening?


Visual Studio - Search through code for Chinese text

I am trying to figure out if it's possible to search through code and stop at lines that contain Chinese characters?


Similar Rule for People with the Privilege of Closing Questions or Putting Them on Hold?

If a user has a certain number of questions that were closed or put on hold, that user cannot ask more questions for a certain time (or even prevented from asking at all). For those with close privilege, is there a rule that say something like if you improperly close or put a question on hold, then you'd be suspended from doing so for some time? So that people won't be trigger-happy with the close button? This seems... unbalanced.


Proof that continuous function on $ [0, 2]$ has $f(x) = f(x-1)$ for some $ x$

Proof that if continuous function on $[0, 2]$ and $f(0) = f(2)$, then for some $x: f(x) = f(x - 1)$


Unable to fill color in the intersection region of $y =\sqrt{x}, y =x , using tikz by the given code.  Please help, thanks  \documentclass{article} \usepackage{tikz,pgfplots} %\usepackage[x11names]{xcolor} \usepackage{tikz} \usetikzlibrary{intersections} \pgfdeclarelayer{bg}    % declare background \pgfsetlayers{bg,main}  % order of layers (main = standard layer) \pgfplotsset{compat=1.13} \usepackage{amsmath} \usetikzlibrary{positioning}      \begin{document}      \begin{tikzpicture}[domain=0:2, scale = 0.75, dot/.style={circle,fill,inner sep=1pt}]     \draw(-4,0)--(4,0);     \draw (0,-4)--(0,4);      \draw(0,0)--(3,3);     %\draw[black, line width = 0.50mm]   plot[smooth,domain=0:2] (\x, {\sqrt{\x}});      \draw[blue,line width = 0.50mm]   plot[smooth,domain= 0:2,variable=\y]     ( {3(\y)^2},\y);     \draw(1,0)--(1,1);     %\draw[black, line width = 0.50mm]   plot[smooth,domain= -2:2] (\y,  {(\y)^2});     \draw(2,3)node($y=x^2$){$y=x$};     \draw(5,2)node($x=y^2$){$\sqrt{x}=y$};     \draw [left=.2cm](0,0)node(o){O};     \draw[right=.1cm](1,1)node(a){A};       \begin{pgfonlayer}{bg}    % select background     \clip plot[smooth,domain=0:2] (\x, {\x});     \fill[red]  plot[smooth,domain= 0:2,variable=\y] ({(\y)^2},\y);     \end{pgfonlayer}     \end{tikzpicture}  \end{document}


how to print 20 random number between 5 and 25 in java?

I'm using Java. I would like ask the user to enter a number between 5 and 25. Lets say the user enter 6. The program then needs to print 6 random numbers. When the user enters 20, the program must print 20 random numbers between 5 and 25.


Remove elements from javascript object with list of keys

This should be simple, but I'm hitting a wall:  I need to take this object:  {   'a': 'foo',    'b': 'bar',    'c': 'baz',   'd': 'moo'   // etc...   'z': 'farfegnugen' }   And REMOVE the items with keys matching an unknown list: {'a', 'c', 'f'} or just {'a'}...


Trapped in the "Configuring ttf-mscorefonts-installer"

I finally installed Wine (the program to run exe files) and it took a very long time to install.    Now, I have a package configuration window that is pink and looks like this    .    I don't know what to do at this point and I can not exit out of that window without the whole installation failing and then messing up my sudo apt-get install commands.    I tried hitting Esc and Enter but nothing works.    I've clicked all around the screen too and still, nothing works.  PLEASE HELP!


Unit test for AuthConfiguration.getUsernamePasswordEnabled()

Our SF org had an apex class that was built in/already came with it. I have not touched it nor wrote it. For some reason, one method in its test class is now failing. I have no idea why this could be or how to fix it since I didnt write it. Has anyone else seen this error or fixed it? Here is the apex class: global with sharing class LightningLoginFormController {      public LightningLoginFormController() {              }          @AuraEnabled     public static Boolean getIsUsernamePasswordEnabled() {         Auth.AuthConfiguration authConfig = getAuthConfig();         return authConfig.getUsernamePasswordEnabled();     }         }  Here is the test class: @IsTest(SeeAllData = true) public with sharing class LightningLoginFormControllerTest {   @IsTest  static void testIsUsernamePasswordEnabled() {   System.assertEquals(true, LightningLoginFormController.getIsUsernamePasswordEnabled());  }    }


"merits"and "demerits" &"strengths" and "weaknesses"

What is the difference between "merits"and"strengths" and what is the difference between "demerits" and "weaknesses"?


how decompress File by calling compression file using HUFFMAN

I want to build a file compression using Huffman. When I run the program compress and decompress the file it's OK. I close the program. After closing the program I open the program again. Then I only call the compression file which stores the bit sequence to decompress. But then it shows the null pointer exception. How can I solve it?? Below This are the compression and decompression code.  I save the compression bit into a byte array. This works fine. but the problem arises when I only compress the file and close the program. Then if I want to decompress the file by calling the compression file by running the program again it shows me the null pointer exception. the exception is: Exception in thread "main" java.lang.NullPointerException at compress.Decode.decode(Decode.java:25) at compress.MainClasss.main(MainClasss.java:133)  C:\Users\Tech Land\AppData\Local\NetBeans\Cache\8.2\executor-snippets\run.xml:53: Java returned: 1 public class MainClasss {  public static void main(String[] args) throws IOException {     String s = "";     String test = "";     String decodee = "";        Scanner scan = new Scanner(System.in);        while(true){          System.out.println("pls write the file name");     //   String binaryString ="";       String name = scan.next();            try {          test = new String(Files.readAllBytes(Paths.get("C://Users//Tech Land//Desktop//" + name))); //first read the java file as a string     } //first read the java file as a string     catch (IOException e) {          e.printStackTrace();     }               String de = scan.next();     if (de.equals("com")) {         Encode ob = new Encode();         s = ob.encode(test);         BitSet bitset = new BitSet(s.length());          int bitcounter = 0;         for (Character c : s.toCharArray()) {             if (c.equals('1')) {                 bitset.set(bitcounter);             }             bitcounter++;         }          FileOutputStream t = new FileOutputStream("C://Users//Tech Land//Desktop//" + name, false);         t.write(bitset.toByteArray());         System.out.println("file successfully compressed");          }           } else if (de.equals("dcom")) {         try {              decodee = new String(Files.readAllBytes(Paths.get("C://Users//Tech Land//Desktop//" + name))); //first read the java file as a string         } //first read the java file as a string         catch (IOException e) {              e.printStackTrace();         }          String binaryString = "";         File file = new File("C://Users//Tech Land//Desktop//" + name);         FileInputStream fin = null;         try {             // create FileInputStream object             fin = new FileInputStream(file);              byte fileContent[] = new byte[(int) file.length()];              fin.read(fileContent);                        for (int i = 0; i <= BitSet.valueOf(fileContent).length(); i++) {                 if (BitSet.valueOf(fileContent).get(i)) {                     binaryString += "1";                 } else {                     binaryString += "0";                 }             }             //System.out.println("");             // System.out.println(""+fileContent.length);              System.out.println("" + binaryString);         } catch (Exception e) {             e.printStackTrace();         }          Decode ddecode=new Decode();         String k=ddecode.decode(binaryString);           FileWriter fw = new FileWriter("C://Users//Tech Land//Desktop//" + name, false);              System.out.println("");           for (int j = 0; j < k.length(); j++) {               fw.write(k.charAt(j));          }           System.out.println("successful");           fw.close();            }               }  }


Article class. XeLaTeX compiler. I want the titles of parts to appear in the TOC only (not in the document itself). Is this possible?


Alternative to Shannon's entropy when probability equal to zero

I have a series of objects for which I know the probability of belonging to 10 classes. This probability can be null (see example below with 4 classes: A,B,C,D).      A    B    C    D 1  0.4  0.0  0.2  0.4 2  0.1  0.3  0.4  0.2 3  0.0  0.0  0.0  1.0   In order to get for each object an information about the quality of the classification, I wanted to calculate Shannon's entropy but it does not work when one of the classes has a probability equal to zero (log(0)=-Inf).  My question: Is there a measure similar to Shannon's entropy (or an adaptation) which handles probabilities equal to zero?


I keep having this problem where my painted textures keep turning completely black. I cant just reapply them, because the image itself is being corrupted, or something. Does anybody know how to fix this?


I've read somewhere that every natural $n$ can be expressed using only Fibonacci's numbers which index is superior or equel to $2$. For example $$ 25=F_{8}+F_{4}+F_{2} $$  I wonder if there exists a proof of this statement because I have no clue about it. Maybe an induction ?


How to remove name of parent directory in Python

I am passing a file path to a method. An example is the following: The method--  def example(image):      code not shown   The call to the method--  example("resources/1.png")   In this, I want to remove the "resources/" part using the example method and simply return "1.png". How can I do that?


How to read an environmental config with connection strings and other settings without referencing it in app.config?

I have many Winform(VB.Net) apps with a Local/Dev/QA/Prod environment setup. I would like to dynamically load environmental config information and access it as if it was in the app.config file using System.Configuration. I haven't found a good solution for this yet. Maybe I'm expecting too much and will have to manually deserialize the environmental config. I'm looking for ideas on how to implement this environmental config?  Here's a list of what I'd like:   The environmental config is a file on the file system containing an XML structure(similar to the app.config). Dynamically load environmental config based on environment. Environmental config can contain connection strings and other settings. Multiple additional config files is acceptable. Use the built in System.Configuration calls to access the values. Basically I would like to avoid having to write a custom deserializer.   I would prefer not to use these options if possible:   Using a configsource parameter in the app.config to point to an external config. This would need to be edited for each environment and it would override(I think) the section where it's set. Using a custom deserializer. I know this could be done and it may be the actual solution. It just seems that this should be solvable without doing this. Using System.Environment isn't practical since it reads/writes to the registry for system variables.


When I attempt to edit a specific answer, I cannot seem to edit it. The edit (button, I guess) is greyed out, but only for that specific answer. I can still edit other questions/answers, but not a specific answer    It still allows me to edit other questions/answers, but not that answer. Why is this happening and how do I fix it?  Link:


Commit empty folder structure (with git)

I have data directory in project's root. It has images directory and some files. Here is example:  data ├── images │   ├── image1.jpg │   ├── image2.jpg │   └── image3.jpg  ├── results.csv └── r.txt   What to write in gitignore, to ignore files from data/ directory (that is results.csv and r.txt) and files from images/ directory (image.jpg, image2.jpg, image3.jpg)?  When I commit it, folder structure in repository should be:  data/ └── images/   So, I just want empty folder structure to be commited.


If $f:I\subseteq \Bbb R \rightarrow \Bbb R$ is injective and everywhere continuous in its domain then $f^{-1}$ is also continuous everywhere. Here  $I$ cannot be discrete set and $f$ is single variable function The above statement is always correct or not? I thought it is always correct. Am I correct or not?


A subgroup of $S_n$ having index 2 is $A_n$.

I want show that      If $ n  \geq 3$ , A subgroup $H$ of $S_n$ having index 2 is $A_n$.   Say $H$ is such a subgroup. Since $A_n$ is a normal subgroup of $S_n$,$H$ normalizes $A_n$ .  By 2nd isomorphism theorem , $HA_n$ is a group such that $$ HA_n / A_n \mbox{ is isomorphic to } H/ H \cap A_n$$  What shall i do?


I have created a custom script  #! /bin/bash  for i in {1..$2};do      mkdir $1__${i}  done  $1 argument>> directory name type:string $2 argument>> index type:integer for creating multiple directories. If i give a command as follows dirmake gamma 6 for making gamma__1 to gamma__6, the only directory that's being created is gamma__{1..6}/ what am i doing wrong?    Does the argument only be taken as a string?


If for every sequence $(x_n)$, $x_n \to x_0 \implies (f(x_n))$ is a Cauchy sequence, then is $f$ continuous?

Given $f:D \subseteq \mathbb{R} \to \mathbb{R}$, if for every sequence $(x_n)$ in $D$ such that $x_n \to x_0$ is true that $(f(x_n))$ is a Cauchy sequence, then is $f$ continuous? This is what I know:  Every Cauchy sequence is a convergent sequence. $f$ is continuous if and only if $x_n \to x_0 \implies f(x_n) \to f(x_0)$ for every sequence $(x_n)$.  However, I only know that $f(x_n) \to a \in \mathbb{R}$; how can I see that $a = f(x_0)$ and then have the continuity of $f$? If the result is false, please show a counterexample, i.e., a discontinuous function such that for every $x_n \to x_0$ I have $(f(x_n))$ Cauchy.


Action delegate uses the last values of variables declared outside foreach loop

I have this piece of code:  int i = 0; foreach(var tile in lib.dic.Values) {     var ii = i;     var t = tile;     Button b = new Button( () = > { MainStatic.tile = t; } );     Checkbox c = new Checkbox( () = > { lib.arr[ii].b = !lib.arr[ii].b; } );     i++; }   While the above code works as it should, this piece below:  int i = 0; foreach(var tile in lib.dic.Values) {     Button b = new Button( () = > { MainStatic.tile = tile; } );     Checkbox c = new Checkbox( () = > { lib.arr[i].b = !lib.arr[i].b; } );     i++; }   …will always execute the delegates with the last values of i and tile variables. Why does this happen, and why do I have to make a local copy of those vars, especially non-reference type int i?


How to align a Nvme SSD partiotion after installation?

I've install Ubuntu 16.04 in a Nvme SSD,but I found the partion 6 isn't  aligned automatically  through parted command:    sudo parted /dev/nvme0n1 (parted) align-check optimal 6  6 not aligned   This is the output of fdisk:  Disk /dev/nvme0n1: 238.5 GiB, 256060514304 bytes, 500118192 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: gpt Disk identifier: C49EAE3F-0A58-468E-99E5-2B51CB2A2FBC  设备               Start    末尾    扇区   Size 类型 /dev/nvme0n1p1      2048   1026047   1024000   500M EFI System /dev/nvme0n1p2   1026048   1288191    262144   128M Microsoft reserved /dev/nvme0n1p3   1288192 217038149 215749958 102.9G Microsoft basic data /dev/nvme0n1p4 477204480 478126079    921600   450M Windows recovery environment /dev/nvme0n1p5 478126080 500117503  21991424  10.5G Windows recovery environment /dev/nvme0n1p6 217038150 477204479 260166330 124.1G Linux filesystem  Partition table entries are not in disk order.   So how could I realign the partition?(expecting not reinstall os )


Every pokemon has something called nature. It can increase some stats and make pokemon better overall.  What are the natures and what do they give?


do I need to change terminal at mumbai airport?

I am traveling through Indigo from Oman to Mumbai to Bagdograh(Siliguri).I heard that I've to change airport in order to change terminal from 1 to 2. How long does it takes? The next flight to Bagdogra is after 4.5hrs of arrival, is it enough for me to reach and do the immigration?


Which badges on this site are so rare very few people have earned them? Please tell me a badge that has less than ten people who have earned it. Also please don’t tell me badges that no one ever earned and never will. Please do tell me badges that no one has earned but can earn. Thank you for helping me.


How to map right shift to slash using xmodmap?

How to map Shift_R to slash (/) using xmodmap?


Don't allow edit suggestion during grace period

I just edited  that contained some code that was overall neat and correct, but wouldn't compile. I made it compile clean and (in my opinion) more readable.  The edit got rejected as too minor, because during my edit the OP made the code compile-clean in the grace period and thus in the diff that shows up to the reviewers, only the parts making the code more readable showed up. Such an edit is a too minor one, without question.  In my opinion there are two possibilities to solve this kind of "conflict":   When user A has edited a post and user B (>2k rep, or original author) has edited that post in the meantime user A gets a message that the post has changed and is asked to revise that edit based on the changes made in the meantime. The easier one: Don't allow edit suggestions in the grace period.   I don't care about the missing reputation I would have gotten if the suggestion had been approved. I just don't like my suggestions being reviewed on a false basis - because the diff that is displayed to the approvers does not display the correct edit.  Doing a quick search here on meta I found some questions maybe related to this problem - none of them however addresses the problem of the review based on incorrect diffs:


all mozilla firefox extensions stopped working today and cannot be updated

After using Firefox Quantum 66 for several months with a set of extensions, I started it today and found, that all of them have been moved to the "legacy extensions" section and disabled. The version of FF has not changed (major, minor - still the same). The versions of the addons have not changed. Updates have been disabled on the hardware level (yes, this is a highly customized device, there is nothing anyone can do about it).  They refuse to update as "download failed"  They refuse to install the latest version from file as "your extension is corrupt"  All I want is my extensions back and no one tamper with them.


Why does my wifi speed slow dramatically when more than one person uses it?

Whenever both my roommate and I use the wifi in a certain room in our apartment, it slows dramatically for me. It doesn't slow for him. If he uses it in another room, it's fine; if I use it in another room together with him, it's fine; it's just in this particular room.   Does anyone know of a reason why this is?


I'd like to do some general disk io monitoring on a debian linux server. What are the tools I should know about that monitor disk io so I can see if a disk's performance is maxed out or spikes at certain time throughout the day?


Error during installation of Ubuntu 14.04 (LTS) in windows 8.1

I am currently using windows 8.1 and trying to install ubuntu 14.04 LTS. I want to use ubuntu side by side with windows 8.1, therefore I was trying to install ubuntu in a different drive than C. After downloading the .iso file and installation using wubi, I get the message "An error occurred: Permission denied. For more information please see the log file......."  I am not a computer geek :-). Any help and suggestion would be appreciated.  Thanks.