I have the Irreducible Polynomial $g = X^4 + X + 1$ over $\mathbb{F}_2 E$, the extension of $\mathbb{F}_2 = \{0,1\}$ with root $\alpha$ of $g$.  My previous problems have asked me to find the number of elements in $E$ and see if they may all be represented in the for $a^n$ with $n \in N$ (I believe the answer to these are 16 and no respectively)  I am struggling however to find all the roots of $g$ in $E$ expressed in the form $\nu + \mu\alpha + \lambda \alpha^2 + \gamma \alpha^3$ as my final problem has posed.   Any help would be kindly appreciated.

Let $h$ the irreducible polynomial over $\Bbb F_2 = \{0, 1\}$  $$h  =  x^4 +x +1$$  Let $E=\Bbb F_2(\alpha)$, i.e. the field $\Bbb F_2$ extended with $\alpha$, where $\alpha$ is a root of $h$.   How do we determine the numbers of elements in the extension $E$? Can every non-zero element in the extension be expressed in the form $(\alpha)^n$ for some $n\in\Bbb N$ ? How do we find all the roots of $h$ over the extension $E$?


I have heard many physicists (ex:- Michio Kaku) saying "Warp speed" from Star Trek doesn't violate any known physical laws. But doesn't it violate causality?  Say, we make warp drive possible and travel towards Alpha Centauri (4.22 light years away) in warp speed and reach there, say, within a year (+/- few months) and blow it up. Now using Special Relativity, we could devise a frame of reference wherein the observer would see the Star blow up before we ever left planet Earth. Wouldn't that violate causality and make warp speeds unattainable?

I'm talking about this nonsense:   Now, I'm aware that there are problems with the practicalities (or possibilities) of methods involving exotic matter with negative mass, and that kind of thing has been addressed here:   But in this case my question is different and more specific. Sweeping all the other problems of constructing such a beast under the rug, wouldn't this violate causality?  SR says that the simultaneity and relative ordering of events is dependent on the relative motion of the observer, but that no matter how it works out, if event A causes event B, no observer will see B first. One of the many problems with FTL travel (or signals) is that if any information is sent faster than light, there will exist an inertial frame in which the signal arrives before it is sent, a blatant violation of causality. (I think we can all agree, can we not, that the threshold should be extremely high before breaking assumptions that we're in a causal universe?)  So how is any scheme to travel faster than light, even if it may locally satisfy the equations of GR, not a blatant violation causality according to SR?  Is my understanding of GR incomplete and there's something in it that obviates the causality implications of SR? Or am I correct that FTL claims should be dismissed with extreme prejudice on this basis alone? (Pending a serious replicable experiment showing causality to be breakable.)


$$\mathbb{Z}[\sqrt2]  = \{a + b√2: a,b \in \mathbb{Z}\}$$  The question is asking to prove that if $\alpha$ is a unit in this set, then: $$a^2 - 2b^2 = \pm1$$ I've hit a dead end already:   I wanted to use the fact that there must exist another element in $\mathbb{Z}[\sqrt2]$ such that $\alpha\beta = 1$.  Now I'm lost, since I've just accidentally shown that the difference of $a^2$ and $2b^2$ should be equal to $1$, not that they are both equal to $1$.  Am I going about this the wrong way?

How can I show that the units $u$ of $R=\mathbb Z[\sqrt{2}]$ with $u>1$ are $(1+ \sqrt{2})^{n}$ ?   I have proved that the right ones are units because their module is one, and it is said to me to do it by induction on $b$ and multiplication by $-1+\sqrt{2}$. I have already shown that the units of this ring has norm $1$ and all the numbers with norm $1$ are units, this may help.


I dont know if you remember me but you answered my question earlier today in ubuntu help, but i didnt get it. When my computer turns on it loads into a screen looking like this. It's just a grub command line and i have no idea what to do. All my schoolwork is in it. What do I do?

Yesterday I tried turning on my computer. It led me into this grub menu and I have no idea how to get out. I can't use my computer anymore due to this. What should I do? Do I type in a command or something?


I am currently using Putty virtual machine (UNIX) for my class, and we are doing a short C++ assignment. The assignment is to: "Create a C++ program that tests to see if the file accounts exists and prints a message to say whether the file exists"  This is what I have, but when I try to compile the code, I get this error: error: ‘::main’ must return ‘int’  #include<iostream> #include<fstream>  using namespace std; inline bool exists_test1 (const std::string& name) {  if (FILE *file = fopen(name.c_str(), "r")) { fclose(file); return true; } else { return false; } }  void main() { string s; cout<<"Enter filename"; cin>>s; bool ans =exists_test1(s); if(ans) { cout<<"File Exist"<<endl; } else { cout<<"File Does not Exist"; } }

What is the correct (most efficient) way to define the main() function in C and C++ — int main() or void main() — and why? And how about the arguments? If int main() then return 1 or return 0?  There are numerous duplicates of this question, including:       — For C++, with a very good answer indeed.     Related:


I have a .txt file whose memory is more than 2 GB. The problem is I cannot open it with Notepad, Notepad++ or any other editor programs.  Any solutions?

I mean 100+ MB big; such text files can push the envelope of editors.  I need to look through a large XML file, but cannot if the editor is buggy.  Any suggestions?


let $z$ be a complex variable and $z=0+0i$ , it is clear at all if want to compute $\arg(z)$ then should be check the value of $\tan^{-1}(y/x)$  then $\tan^{-1}(0/0)$ could be $0$ since $0 |0 $ using the divisibility notion or Is it possible to say that $\arg(0)= \infty $ since it's not undefined  ? Where is the approach definition ?

When $z\neq 0$, $\arg z$ is defined to be the set $\{\theta \in \mathbb{R} : z=|z|e^{i\theta}\}$.  What if $z=0$? Usually does one leave the argument of $0$ undefined? Or is $\arg 0 = \mathbb{R}$?


There's a whole bunch of them that look as if they would require one, but actually don't:  Times Square, Trafalgar Square, Union Square, Carnegie Hall, Central Park, Hyde Park, Westminster Abbey, London Bridge, Oxford University, etc.  As opposed to:  The Albert Bridge, the George Washington Bridge, the Eiffel Tower, etc.  Is there a rule, or some sort of historical reason?  Why this is not a duplicate question: This is not about the general rules about articles; nor am I asking for instructions on how to use them; I already know how.

In my native language, we can say:     I have dog   Because I don't want to say a dog (one dog, how many dogs) or the dog (that dog, the listener don't care which dog).  p.s. after 3 years later, I have to say, why I ask this question, is I still cannot grasp how to use the right 'article word'. sometimes, a noun will use an article, sometimes, a noun could not(or omit) the article word before it. there aren't a formula for this. So, I have to remember all the time! I feel so frustrate


"These personal data of yours will be shared with authorized public institutions and organizations." Is this sentence correct?

My non-native English speaking friend just asked me: "Data is..." or "Data are..."?  I said both but that's because I've been desensitized from reading/writing both (especially from writing code and adding quick comments).  My question: Is it acceptable to utilize either for a university paper? Or is one safer than the other (when confronted with stickler professors)?    Related questions:


In an experiment where we have to measure the resistivity of a semiconductor, or it's band gap energy, we use the four probe method, instead of two probe. So what is the advantage of the four probe method over the two probe method?   Here is the experiment I'm talking about:

I have a pretty good understanding of 2-terminal vs. 4-terminal (kelvin) sensing measurements. I understand that in the 4-terminal measurement, current is supplied by 2 terminals that are separate from the voltage sensing terminals. This eliminates the need for (an appreciable amount) of current to run through the leads of the voltmeter, which would cause a slight voltage drop due to the internal resistance of the leads.   My question is - can't that internal resistance be measured quite easily? If it is known, how is 2-terminal sensing any less accurate than 4-terminal sensing if the internal resistance fact is used to compensate?


How do I prove the following statement?     Let $G$ be a $p$-group, $H$ - its normal subgroup, $H\neq \{e\}$. Then the center of $G$   $$ Z(G)=\{a\in G\ \ |\ \ \forall x\in G\ \ ax=xa\} $$   has non-trivial intersection with $H$, i.e. $H\cap Z(G) \neq \{e\}$.   As far as I understand, this is about finding central elements in a normal subgoup. Maybe there is some straightforward way to construct such an element (using inner automorphisms, for instance...)?

If $G$ is a finite $p$-group with a nontrivial normal subgroup $H$, then the intersection of $H$ and the center of $G$ is not trivial.


I posted a question that had a white filter over it. Basically, it still appears on the "newest" questions, and is still clickable, but has a white filter over it, such that it's barely visible. Can anyone explain this phenomenon?  The question, btw, is NOT on hold, and rather has 2 up-votes as of now. I don't know if anyone else can see it as faded too. I would post an image, but my rep is too low. Remember, this is happening on the newest questions category only, not the question itself.

I just refreshed the [iphone]-tag-site, and I'm seeing all kinds of questions with what appears to be a grey overlay (see image). What is this for/why am I seeing this? I have never seen anything like this before..


I'd like to call an API to know if the laptop is plugged into the wall.  If it is I want to defer some CPU intense processing in order to save battery  I'd also like to be informed when this status changes (meaning when the user plugs the charger back in I'd like to be alerted)  in Win32 I'd probally go this route -    is there something like this in .NET/C#?

For the umpteenth time my laptop just shut down in the middle of my game because my power cable had disconnected without me noticing it.  Now I want to write a little C# program that detects when my power cable disconnects and then emits a nice long System beep. What API could I use for that?


I have a div (.content) that has a transform-origin: top left and I need to center it. The thing is, I can only modify CSS of its wrapper (.wrap), but not of the actual div. I've, of course, tried margin: 0 auto, but that's not working. And neither is position: absolute (with left and right set as 0), though if I can avoid using absolute, even better.  Is there any way I can center this div?   This is the outline of my HTML and CSS:    /* The part of CSS that I can't modify */  .content {   height: 350px;   width: 350px;   background-color: darkblue;   -webkit-transform: scale(0.7);   -moz-transform: scale(0.7);   -o-transform: scale(0.7);   transform: scale(0.7);   -webkit-transform-origin: top left;   -moz-transform-origin: top left;   transform-origin: top left; }   /* The part of CSS that I can modify */  .wrap {   margin: 0 auto; }

     Thanks!

How can I horizontally center a
 within another
 using CSS?

Foo foo


I am unable to update through software updater. After clicking install now, it shows "requires installation from untrusted package".   Then there is two options: Settings and OK.  I click OK but the software updater window closes and stops.

I tried installing VLC Player yesterday, and I got the Requires installation of untrusted packages error.  I searched for hours for a solution to this problem, and finally came upon a suggestion that said to change servers for downloading updates from.  I did this, and it gave me a 404 error when I clicked on "Check" in the Update Manager.  I tried switching my server back to the main one (and after that, several other ones), but I am now still getting a 404 error:   And the other error I get when downloading or updating:   Edit: Output of cat /etc/apt/sources.list:  deb-src http://us.archive.ubuntu.com/ubuntu/ precise main restricted #Added by software-properties  # See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to # newer versions of the distribution. deb http://us.archive.ubuntu.com/ubuntu/ precise main restricted multiverse deb-src http://us.archive.ubuntu.com/ubuntu/ precise multiverse universe #Added by software-properties  ## Major bug fix updates produced after the final release of the ## distribution. deb http://us.archive.ubuntu.com/ubuntu/ precise-updates main restricted multiverse deb-src http://us.archive.ubuntu.com/ubuntu/ precise-updates restricted main multiverse universe #Added by software-properties  ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team. Also, please note that software in universe WILL NOT receive any ## review or updates from the Ubuntu security team. deb http://us.archive.ubuntu.com/ubuntu/ precise universe deb http://us.archive.ubuntu.com/ubuntu/ precise-updates universe  ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu  ## team, and may not be under a free licence. Please satisfy yourself as to  ## your rights to use the software. Also, please note that software in  ## multiverse WILL NOT receive any review or updates from the Ubuntu ## security team.  ## N.B. software from this repository may not have been tested as ## extensively as that contained in the main release, although it includes ## newer versions of some applications which may provide useful features. ## Also, please note that software in backports WILL NOT receive any review ## or updates from the Ubuntu security team. deb http://us.archive.ubuntu.com/ubuntu/ precise-backports main restricted universe multiverse deb-src http://us.archive.ubuntu.com/ubuntu/ precise-backports main restricted universe multiverse #Added by software-properties  deb http://us.archive.ubuntu.com/ubuntu/ precise-security main restricted multiverse deb-src http://us.archive.ubuntu.com/ubuntu/ precise-security restricted main multiverse universe #Added by software-properties deb http://us.archive.ubuntu.com/ubuntu/ precise-security universe  ## Uncomment the following two lines to add software from Canonical's ## 'partner' repository. ## This software is not part of Ubuntu, but is offered by Canonical and the ## respective vendors as a service to Ubuntu users. deb http://archive.canonical.com/ubuntu precise partner deb-src http://archive.canonical.com/ubuntu precise partner  ## This software is not part of Ubuntu, but is offered by third-party ## developers who want to ship their latest software.


I might be having a brainfart here, and I probably am, however it's somewhat hard to word my problem, so I'm having some issues finding help.    Essentially, in Java, you can do something like this:  // create some generic class public class Test {    public void random() {} }  // other class public class Test2 {    public Test2() {       someFunction(new Test() {          public void random() {             System.out.println("howdy");          }       });    }     private someFunction(Test t) {       t.random();    } }   I'm looking to convert this idea (modifying the contents of a class while passing it as a variable) into C#. I understand it can be done with lambda expressions, however I cannot for the life of me seem to figure it out. Any help is appreciated.

Is it possible to have an anonymous type implement an interface?  I've got a piece of code that I would like to work, but don't know how to do this.  I've had a couple of answers that either say no, or create a class that implements the interface construct new instances of that. This isn't really ideal, but I'm wondering if there is a mechanism to create a thin dynamic class on top of an interface which would make this simple.  public interface DummyInterface {     string A { get; }     string B { get; } }  public class DummySource {     public string A { get; set; }     public string C { get; set; }     public string D { get; set; } }  public class Test {     public void WillThisWork()     {         var source = new DummySource[0];         var values = from value in source                      select new                      {                          A = value.A,                          B = value.C + "_" + value.D                      };          DoSomethingWithDummyInterface(values);      }      public void DoSomethingWithDummyInterface(IEnumerable<DummyInterface> values)     {         foreach (var value in values)         {             Console.WriteLine("A = '{0}', B = '{1}'", value.A, value.B);         }     } }   I've found an article  that describes one approach. Is this the best way of doing this?


A common experiment to demonstrate that air has weight is to weigh a deflated balloon and an inflated one. The deflated balloon gives a lower reading on the balance and hence we conclude that air has weight.   However, if we think about it, what we have done is just 'encase' a part of the atmosphere inside the balloon. When the air was outside the balloon it had no 'weight'. If we hold a weighing machine in the air, it reads $0$. Why does putting the air inside a balloon suddenly give it mass?  In other words, if the air inside the balloon exactly displaces its mass of air. So the force due to gravity on it must be cancelled with the upthrust due to buoyancy. How then does the balloon filled with air weight more?

Consider the experiment in .  The experiment includes using a ruler as a lever, with an inflated balloon on one side and a balloon which is not inflated on the other.  The aim of the experiment is to show that air has mass.  I have seen many kids performing similar experiments.  But, if the air pressure inside the balloon is equal to that outside, then the buoyant force will cancel out the weight of the air inside the balloon, won't it?


Update: Since summer 2015 Biber is also available trough the repositories for 64-bit MikTeX. There is no need to install Biber manually, it can be installed via the package Manager.  I am using MikTex 64 bit. Unfortunately it has no biber.exe. Is it possible to take Biber from, e.g., MikTex 32 bit? If yes, how to do that? I've heard that biber.exe needs perl library.

Update: As of summer 2015 Biber is also included in the 64-bit repositories for MikTeX. There is no need to install Biber manually any more, it can simply be installed via the Package Manager just like other packages.   The question  describes how to use Biber with MiKTeX. But on the 64-bit version of MiKTeX Biber isn't installed.  How it is possible to install Biber on a 64-bit version of Windows?  Can I use this ?


We need to upgrade two SQL Servers for our projects to SQL Server 2012. Since we’re not db-admins or familiar with such migrations, I wanted to ask you if you could tell me what we have to be aware of and check before upgrading.  Some information about the servers:  Project 1:   SQL Server 2008 No procedures No functions No views   I think this should not really be a problem to upgrade to 2012 right? Is there anything else we have to make sure?  Project 2:   SQL Server 2005 ~700 procedures ~50 functions ~100 views   I think this will be more of a problem… is there any logic that won’t work on SQL Server 2012 that did on SQL Server 2005?  Is there a list of keywords which are not supported anymore?  Are there other problems that could happen during / after the migration?  Thanks in advance

I have recently upgraded SQL Server 2000 database to 2008 R2.    What I did was:   Shutdown SQL Server 2000 (express) service on old machine, Move datafiles (mydatabase.mdf and mydatabase.ldf) to new machine, Run SQL Server Management Studio 2008, Connect to local database engine, Attach datafiles to database. Change the compatibility level of database to SQL 2008 (100).     Question: What else should I do to make migration complete?  I want to:   use new features like checksumming and full recovery model, make this database to be exactly as it was created in SQL 2008 R2, make this database to be fully compatibile, correct and be perfect suited for new, SQL 2008 R2 database engine.     In other words: I just want to know how to correctly and completly convert old SQL 2000 database to new 2008 R2 database, be calm that everything is done right and be happy with all new features.    I'm asking this question, because I've found a lot of sites on the Internet that says so many different things that makes me confused: some say that it is required to rebuild indexes, another says to do other things... and now I know nothing so I want to hear experienced person opinion and clear, step-by-step instructions. I work for very small company, I'm on my own and I don't want to screw things up.    Sir, I'm really impressed with your answer, I wasn't expecting so much.    So some comments:   The database is now in production. As I said, it was upgraded using deattach-attach method as I desribed in first post and as described on MSDN:  It had to be done quickly, so I was forced to do it that way. Let's forget about how inappropriate could it was and focus on current situation. The users/persmission is not a problem here - there are only few and permissions are simple. The application which use database is compatibile with SQL 2000 till 2012 so this is not a problem either. The database file (MDF) isn't big - only about 1GB.     Few more questions:   You recommend to use backup/restore method, but I did as written above, so can I encounter any problems now? Everything worked without any problem. About checksumming and full recovery model: it wasn't available/enabled on SQL 2000, so I want to use them now. You said that the only thing I need to do is to enable those options in database properties? I've read somewhere, that it isn't enough and I should also rebuild indexes or something. I really don't know, I just asking. I'm prepairing to migrate this database to SQL 2012 - so first it was from SQL 2000 to 2008 R2, now it will be from 2008 R2 to 2012 (it was impossible to do this directly because of lack of support of SQL 2000 databases in SQL 2012). So I understand that I should follow your guide: backup it in 2008 R2 and restore in 2012, then do the rest of your tips, right? Please explain me the backup/restore method: Is it like a dump of database to SQL queries and then restoring it by executing a bunch of queries? Will this method by the way "defragment" my database? If not, how to defragment/optimize it manually? As we were using SQL 2000 Express for years (no management interface), we were doing backups simply by stopping engine and RAR the DATA directory. For now, as we are on SQL 2008, isn't this still better than using backup function in Management Studio? Full recovery mode with frequent Transaction log backups - Where is the Transaction log stored - is it the LDF file? How sould I backup it properly?     I know that my questions may sound silly, I'm not professional database admin, but I am the only person here who can do such "hard core" task like upgrading the database engine. I'm also sure that your knowleadge will help a lot to other people like me.  Thank you very much for your time and knowleadge, I really appreciate this.


I am trying to start httpd.exe on windows 8 as a service. This is the instruction that is giving me problems:  Start apache in a DOS box: >httpd.exe Install as a service: >httpd.exe -k install   The first command works fine, but the second fails as follows:  C:\Apache24\bin>httpd.exe -k install Installing the Apache2.4 service (OS 5)Access is denied.  : AH00369: Failed to open the WinNT service manager, perhaps you forgot to log in as Adminstrator?   The account I am using is a local account with administrator privileges. When using this account I am able to install software, administer other users accounts, etc. I do not see an "Adminstrator" or "Administrator" account on the "Control Panel\All Control Panel Items\User Accounts\Manage Accounts" screen. I have tried the following, as suggested in another post:  runas /noprofile /user:Administrator cmd   That results in a prompt for a password, which I do not seem to know. The PC came with Windows 8 preinstalled and if I was ever asked for an Administrator password I can not recall my response.  So my question is, how can I install a running application as a service on Windows 8 without knowing the password to the "Administrator" account? Or, how can I discover or reset the password to the "Administrator" account?

I was trying to use mklink command in cmd (I have Windows 7 OS) I was logged on as administrator, but I got:  You do not have sufficient privilege to perform this operation.  I used the same command in Vista, it worked OK. Any ideas why it does not work in Windows 7?


I read  about why Type erasure makes java less powerful then some languages in generic. In wiki page, here is one example:  public class MyClass<E> {     public static void myMethod(Object item) {         if (item instanceof E) {  //Compiler error             ...         }         E item2 = new E();   //Compiler error         E[] iArray = new E[10]; //Compiler error     } }   I understand why E item2 = new E(); should be compiled error because we really don't know class E before calling them. But I don't know why this line should be error:  if (item instanceof E) {  //Compiler error    ... }   Because as I know, when compiling java application, all generic type will replaced by its concreted type. for example:  // all E will be substituted by Integer  MyClass<Integer> myObject = new MyClass<Integer>();    So I don't think why should Java throws compile error at above line.

What is the concept of erasure in generics in Java?


I am unable to confirm if the r7 360 is supported by the amdgpu driver on Ubuntu 20.04. On the ubuntu wiki ot states R7, but not explicit model numbers. Some r7 are cgn 1st gen and others are cgn second gen.

I have a device on which I would like to install Ubuntu. How do I find out if Ubuntu will work on it?


I saw this lockscreen wallpaper in my windows 10 laptop. Only thing i could understand was that this is in Rome, Italy. No name was given with the info. A google search on walls in Rome didn't provide any answers. Can someone please help me understand which wall is this?

Windows 10 has an extensive collection of lock screen photos, many of which have  here on Travel.SE.  Is there a website which lists the location of all of these photos? I imagine Microsoft has purchased an official license, so they should have a record about the photographer and the place where the photo was taken.


If photons lack mass, why are they affected by gravity? Is this because photons have a lot of energy and m=e/c^2?

I understand that a black hole bends the fabric of space time to a point that no object can escape.   I understand that light travels in a straight line along spacetime unless distorted by gravity. If spacetime is being curved by gravity then light should follow that bend in spacetime.  In Newton's Law of Universal Gravitation, the mass of both objects must be entered, but photon has no mass, why should a massless photon  be affected by gravity in by Newton's equations?  What am I missing?


The study found relatively consistent benefits [for/of /to] using the drugs in severely ill patients.

I encountered an expression:     key benefits to using [something]   To my mind the version below would sound more natural:     key benefits of using [something]   Are both versions correct? Is there any difference in meaning?


Using SVN for version control, is it possible to discover when a specific code was inserted at a given file?   Can i give to SVN, or using tortoiseSVN, a piece of code and a file and SVN discover when that code was first inserted ?

Is it possible to see the history of changes to a particular line of code in a Subversion repository?  I'd like, for instance, to be able to see when a particular statement was added or when that statement was changed, even if its line number is not the same any more.


[Solution]The issue has been resolved. I ran the 'Advanced Renamer' program as suggested, and changed the file type of my make file from make to make.mak. Then after the program was done I removed the extension and it showed as type File. From then on, every extensionless file that I create has that type.  Recently my system (Windows 7) had become infected by some Adware. I removed its entries in the registry and deleted the relevant files in my Program Files and ProgramData folders. A few days later I was working on a coding project when I noticed my make file had a type that was the name of the adware program.  Here is an image of my make file in a folder:   I'm pretty sure that the adware is not active anymore. However, I'm not sure how I can change the file type of an extensionless file. How can I change the type back to the generic 'File' descriptor?  [Edit] I have attempted to use the suggested answers in the thread linked but HKEY_CLASSES_ROOT\Type was not present in my directory. I then tried to create a new key: HKEY_CLASSES_ROOT\..  This did not change the file assosiation back to 'File' unfortunately. So I removed the HKEY_CLASSES_ROOT\. key, but it didn't change the association either.  [Edit 2] To clarify on the extension: The image shown is already showing the file extension. That is to say, there is no file extension. I have the hide file extensions for known file types unchecked in the image and my make file has no extension. All extensionless files will show the file type 'AulleCheapPrice.'

The launcher for Mass Effect 2 mistakenly associates itself with files with no extension. The game's patch apparently fixes this, but it's too large for me to download on this connection. How do I fix this myself? It doesn't appear on Windows' "set associations" list. (Windows 7 x64)


How to install Printer on Network of Kyocera Ecosys M2040dn on Ubuntu 14.04,16.04,18.04  ?????

In Ubuntu 14.04, my Kyocera P2040dn printer prints only from the user that installed the driver. How to make it print under other users?


I don't understand the meaning of -y.  command:   apt-get install -y clickhouse-client & sudo apt-get install -y passenger   There are many commands have -y.

I always see commands like this  apt-get -y install    What is the -y tag for and what is the difference between apt-get install with and without the -y tag?


Ok I had played , one of the odd things was that after completing all the objectives of a particular level you used to get certain rewards like the shotgun SC-20K attachment or the colored nightvision.   Can you actually use these ? Or are they just for show ? Because I could never get an option to use these.   I just want to know if that was how the game was built or is it a bug in my system ?

In the PC version of Splinter Cell: Double Agent, how can you use the rewards that you receive after each mission? For example, the shotgun attachment, or the colored night vision?  My list shows that the rewards are there, but I can not figure out how to use them.


Firstly I'm not sure whether I'm asking at the right place or not (either here or stackoverflow). Sorry, if I'm not.  Before that:  My site runs on apache and developed using PHP.  What I'm trying to do is:   My client can generate a registration page for its customers. The default generated registration page URL is something like www.mydomain.com/test.php?clientid=2 But the url is long and ugly, so I created another option for the client to generate a prettier looking url, which starts with a shorter domain (eg: like.my) and a customizable 'path' after that. So the resulting pretty url my client want is like http://like.my/page. So there is a simple way to redirect the traffic from http://like.my/page to http://www.mydomain.com/test.php?clientid=2? Btw I have thousands of clients and each of them would have different pretty url pointing to different other pages.

This is a  about Apache's mod_rewrite.   Changing a request URL or redirecting users to a different URL than the one they originally requested is done using mod_rewrite. This includes such things as:   Changing HTTP to HTTPS (or the other way around) Changing a request to a page which no longer exist to a new replacement. Modifying a URL format (such as ?id=3433 to /id/3433 ) Presenting a different page based on the browser, based on the referrer, based on anything possible under the moon and sun. Anything you want to mess around with URL   Everything You Ever Wanted to Know about Mod_Rewrite Rules but Were Afraid to Ask!  How can I become an expert at writing mod_rewrite rules?   What is the fundamental format and structure of mod_rewrite rules? What form/flavor of regular expressions do I need to have a solid grasp of? What are the most common mistakes/pitfalls when writing rewrite rules? What is a good method for testing and verifying mod_rewrite rules? Are there SEO or performance implications of mod_rewrite rules I should be aware of? Are there common situations where mod_rewrite might seem like the right tool for the job but isn't? What are some common examples?   A place to test your rules  The  web site is a great place to play around with your rules and test them. It even shows the debug output so you can see what matched and what did not.


Is there a term for a word that means itself? For example the word word means itself and is a word.

I'm having fun with paradoxes, and I'm trying to come up with a catchy word for non-self-descriptive.  Maybe "autosemantic" fits the bill for self-descriptive (definitely open to other suggestions!), but I'm having a hard time negating it in a natural way.  For an example of the sentence I'm trying to construct:     Is "inautosemantic" inautosemantic?   It just isn't flowing.


A  says     teachers and test graders want to see the words trying to instead of tryna.   I understand this sentence clearly.  I just wondering whether "rather than" could be substituted for "instead of".  I  and  gives some clear rules (I modified it a little bit)     (rule#1) "Instead of" is used when you were given a plan and you want to change it.       (rule#2) "Rather than" connotes a situation where you are asked about something and you like both options and you need to choose your favorite.   I suppose most VOA articles use the correct words though, the use of words does not seem to be a plan. That is more like the rule#2.  Which rule is supposed to be used in this context? Are "instead of" and "rather than" interchangeable in the case?

I have a sentence:     Please show me the right way so that I can do that rather than take blind action.     Is this sentence grammatically correct?   Can I use instead of to replace rather than? If replaced, the meaning of this sentence is changed?   What is the difference between rather than and instead of? Can you show me some examples to distinguish them?


I'm using oracle plsql and I have a question. I have table of Tests and Table of Schools.   How can I make a query that will put null or some other by my demands?   I mean, to put null or some numeric number in the execution.

Also how do LEFT JOIN, RIGHT JOIN and FULL JOIN fit in?


, but I came to not sure about this issue and thought I should ask a follow up question to clarify the details.  First, I ran chkdsk /r on drive which got some physical bad sectors. this was my mistake cause of data loss with marking bad clusters, so I canceled chkdsk on stage 4 (bad cluster searching in user files) and 1~3 stages are passed with no errors, in that time chkdsk was working like freezing on stage 4.  So basically chkdsk didn’t show any “Windows replaced bad clusters in file 25702” or any kind of messages on stage 4 while running, I canceled it before chkdsk show the messages.  So my guess are in two ways:   chkdsk didn’t detect any bad cluster, errors at the point when chkdsk running as screen show chkdsk was doing some, fixing bad clusters and just couldn’t show messages for while because i canceled. in this case data is already changed.   I am pointing at possibility of 2.  This issue make me paranoid and I want to know is there any way to make sure, this drive is already gone and I moved all data to new drive after cancel chkdsk. I hope data is not changed but, if there is way to know chkdsk didn’t do anything (yet) to data as prompt screen showed, it is fine. Any advice is welcome to make conclusion.

I ran chkdsk /r on drive with some bad sectors, and I manually aborted chkdsk at stage 4. I took this screenshot just before exiting chkdsk.    1 ~ 3 stages are passed with no error messages and stage 4 only showed "looking for bad clusters in user file data..." nothing more, I aborted chkdsk at this point as shown in the screenshot.  So, at stage 4, since no messages were recorded on prompt yet, that means stage 4 didn't do anything to data (clusters) yet.  Am I correct?


There is a story that  a worker at the airport, while unloading a number of boxes,  accidentally discovered a man who was hiding in a box in order to save the cost of the trip.  The man was lying on the top of a pile of WOOLEN GOODS.   And my question is if I intend to replace WOOLEN GOODS with some other type of goods, for example, CLOTHES or CLOTHING, which one is better?  And what is the difference on this occasion?  Please explain in detail, thanks!

Do some google I find that clothes work like objects like:        You should pack your clothes.  → Yes   You should pack your clothing. → No      Can you tell me the main difference between clothing and clothes?


In a login script I found onlline, the creator added this function to prevent SQL-injection attacks.  function Fix($str) {     $str = trim($str);     if(get_magic_quotes_gpc()) {         $str = stripslashes($str);     }     return mysql_real_escape_string($str); }   Since I read that magic_quotes_gpc is (or has been) removed, it feels like this function is a bit outdated. Wouldn't just simply using mysqli_real_escape_string($user_input) add sufficient security?

If user input is inserted without modification into an SQL query, then the application becomes vulnerable to , like in the following example:  $unsafe_variable = $_POST['user_input'];   mysql_query("INSERT INTO `table` (`column`) VALUES ('$unsafe_variable')");   That's because the user can input something like value'); DROP TABLE table;--, and the query becomes:  INSERT INTO `table` (`column`) VALUES('value'); DROP TABLE table;--')   What can be done to prevent this from happening?


My family and I took a flight on Jet Blue last February and I need to find the flight number and ticket number so I can claim my points.

The question  only deals with flights in the US sourced from the  . Is there some similar source for EU, Asia etc?


So, I have an Ubuntu server that I'd like to open a port for. I tried ufw allow 25565, but when I try and ping the IP address (with the port listening) it doesn't work. You can tell that it actually receives the ping, as the Minecraft server essentially has a seizure, but no information is sent back. I know that I'm supposed to port forward through the router, but I'm not sure I can do that through the terminal. Any solution? Thanks in advance.

I have an old Ubuntu server (13.04), and want to open a port for this online game server style software for a mate. I need a port open, and to tell it that port (I know how to tell the game that port).  For the sake of argument, let the port I want to open be 12345.  How do I do such, with no access to a GUI, only a Bash shell. Both how to open the port, and how to fiddle with the firewall so that port is visible to the world.   Thanks!  EDIT: I can port forward it internally (iptables esque), but I don't know what firewalling software I have installed. Is there an easy way to find that out? Also, how do I port forward the router as well, all from the terminal. Sorry for the earlier lack of detail


When I enter the /testfor command, and a player stands on the area the command block is detecting, a chat message appears saying "found MarioTimeWhoa". This didn't used to happen. How can I fix this?

I want to make a tellraw shop but to activate command blocks I want to use /setblock command when clicked on a text. Is it possible to disable "Block placed" text showing up?


so the problem is strange, cause it's happening on some systems only.  If you have this line:  parse_url('/€?€#€')   On local system with PHP version 7.0.4 it gives me the following result:  array(3) {           ["path"]=>         string(4) "/▒_▒"   ["query"]=>        string(3) "▒_▒"    ["fragment"]=>     string(3) "▒_▒"  }        Something like that is experienced here:            Enter in the $url box:  /€?€#€   But here it's working just fine, although the PHP version is the same as on my machine:   Any idea why is that happening?  The expected parsed url result should be:  array(3) {   ["path"]=>   string(4) "/€"   ["query"]=>   string(3) "€"   ["fragment"]=>   string(3) "€" }   EDIT:  File encoding is UTF-8, PHP internal encodings are also UTF-8, everything that can be set on the server is already UTF-8.

I'm setting up a new server and want to support UTF-8 fully in my web application. I have tried this in the past on existing servers and always seem to end up having to fall back to ISO-8859-1.  Where exactly do I need to set the encoding/charsets? I'm aware that I need to configure Apache, MySQL, and PHP to do this — is there some standard checklist I can follow, or perhaps troubleshoot where the mismatches occur?  This is for a new Linux server, running MySQL 5, PHP, 5 and Apache 2.


I'm running into an issue where emails are not sending when an Org Wide Email Address is not verified. No exception is thrown either.    In apex, I'm resolving the ORG wide that matches the users email:  Id emailId = [SELECT Id FROM OrgWideEmailAddress WHERE Address = :userEmail].Id;  I'd like to somehow check if their email is verify and fall back to a "default" email when it is not.     I'd expect this to just be a field on the  I could filter on, but unfortunately there is not.  Is there any way to check this via apex?

I have created a picklist with selectOptions as Org-wide email address as below  VF Code  <apex:selectList value="{!emailFromAddress}" size="1" multiselect="false">               <apex:selectOptions value="{!OrgWideEmailAddress}"></apex:selectOptions> </apex:selectList>   Controller Code  public List<selectoption> getOrgWideEmailAddress(){         List<SelectOption> lstEmailIds = new List<SelectOption>();          // Use Organization Wide Address         for(OrgWideEmailAddress owa : [select id, Address from OrgWideEmailAddress]) {            lstEmailIds.add(new SelectOption(owa.id,owa.address));         }        return lstEmailIds;     }   The selected email Address Id is used to set as OrgWideEmailId for an email as below  Messaging.SingleEmailMessage message = new Messaging.SingleEmailMessage(); mail.setOrgWideEmailAddressId(emailFromAddress);   But when i select a Non verified email address then email sending fails. Hence i want a way to filter & get only verified email address to show in Picklist options.  Tia.


I want to use ubuntu. but I dont know how I can Install it. I am A new in this os. So can tell me please how I can install ubuntu 15.10 on my Laptop Lenovo Flex10 with Windows 10 as second System?  Thank you Sincerely EldarAzal

I'm absolutely new to Linux. I would like to know how to install Ubuntu alongside the pre-installed Windows 8+ OS.  Should I do it with Wubi, or through the Live USB/DVD?  What steps do I need to take to correctly install Ubuntu?


A little while back my iPhone X started having motherboard issues and was unable to be booted up. I was using Google Authenticator to store many accounts, some of which may be impossible to get to without those codes. From what I understand Google Authenticator is tied to your hardware, and as a result when I restored my icloud backup to a new phone, the Google Authenticator keys are lost. This leaves me no choice but to try to get the old iPhone working so I can safely restore an iCloud backup to it and have the google authenticator codes appear again. If it’s the same phone this will work fine. The question is: If the phones motherboard is replaced, does that effectively change the hardware so much that google authenticator won’t recognize it as being the same phone?

My iPhone 7 had issues and I had done encrypted backups using iTunes. Apple gave me new iPhone as replacement. When I restored from iTunes backup, my Google Authenticator is blank.   I have lot of sites configured and I am not sure what to do now. Any help? I did download the backup codes from Google and it gave 10 codes. How do I used the codes for other sites like coinbase, Amazon, etc.?


What I am trying to build is a list of enum classes that have got more advanced valueOf methods. Since that method cannot be overwritten and therefore extended, I have thought to make a class holding all enumerations which have advancedValueOf methods and run it by lambda. The problem I am facing is that registration of the enum is in static{} code, which is triggered AFTER the enum is checked for the first time.  public enum SimpleEnum {     ONE,     TWO;     static     {         EnumTest.registerEnum(SimpleEnum.class, SimpleEnum::advancedValueOf);     }     public static SimpleEnum advancedValueOf(String s)     {         return ONE;//This method would find enum by its parameters     } }  //------------------------------------------------  public class EnumTest {     private static final Map<Class<?>, Function<String, ?>> _advancedValueOfEnums = new HashMap<>();      public static void main(String[] args)     {         getValue(SimpleEnum.class, "1");     }      public static <T extends Enum<T>> void registerEnum(Class<T> enumClass, Function<String, T> advancedValueOf)     {         _advancedValueOfEnums.put(enumClass, advancedValueOf);     }      public static void getValue(Class<?> enumClass, String value)     {         System.out.println("Contains=" + _advancedValueOfEnums.containsKey(enumClass));     } }   Message printed to the console is "Contains=false". What can I do to make it "Contains=true"?  This answer:  shows what is wrong with accessing static field from enum constructor, I am asking about accessing static value of enum from a different class which should have already been initialized.

Why can't enum's constructor access static fields and methods? This is perfectly valid with a class, but is not allowed with an enum.  What I'm trying to do is store my enum instances in a static Map. Consider this example code which allows lookup by abbreivation:  public enum Day {     Sunday("Sun"), Monday("Mon"), Tuesday("Tue"), Wednesday("Wed"), Thursday("Thu"), Friday("Fri"), Saturday("Sat");      private final String abbreviation;      private static final Map<String, Day> ABBREV_MAP = new HashMap<String, Day>();      private Day(String abbreviation) {         this.abbreviation = abbreviation;         ABBREV_MAP.put(abbreviation, this);  // Not valid     }      public String getAbbreviation() {         return abbreviation;     }      public static Day getByAbbreviation(String abbreviation) {         return ABBREV_MAP.get(abbreviation);     } }   This will not work as enum doesn't allow static references in its constructor. It however works just find if implemented as a class:  public static final Day SUNDAY = new Day("Sunday", "Sun"); private Day(String name, String abbreviation) {     this.name = name;     this.abbreviation = abbreviation;     ABBREV_MAP.put(abbreviation, this);  // Valid }


By default, a number of system directories (such as ~/Library) are hidden in OS X (ie. they don't appear in Finder):    I know I can do this through the GUI but I would like to add a script to my  that does this automatically for certain system directories.  Is it possible to remove the hidden flag for a file/directory from the command line?

I often use the "Library" folder in my home folder ~/. The Library folder there (~/Library/) is shown (unhidden), and that is not the question.  I would like to also always show the menu point "Library" in the Finder menu under the word "Go". Normally it only shows when I hold the Option ⌥ key the menu is open. I tried to assign "Library" to the shortcut for "Downloads" and gave Downloads another shortcut, like it worked for "Save As…". But it only shows up then holding down the Option ⌥ key.  How to always show the "Library" menu point under the Finder "Go" menu, without holding down a key?  In the screenshot I am holding down the Option ⌥ key:


On a deep level, how does copying something to the clipboard work? Is there a file that stores the text or image I copy somewhere?  I found  where the question was never answered. I also found a lot of references to xclip. I don't currently have xclip installed, but my clipboard works fine--eg I could copy something from Firefox and paste it into terminal with no issues. So, clearly something must be happening on a different level than xclip. What is that and how does it work?

Since they are "saved to clipboard", the contents must be stored somewhere.  Are they stored in a file?


I know there have been a number of questions asked regarding the performance boost of using a pre increment (decrement) vs post.  And from what I can infer, the majority of C/C++ compilers will change  for (int i =0; i<N; i++) { ... }   to  the following as an optimization  for (int i =0; i<N; ++i) { ... }   I have been doing a lot of code review lately, I find many instances where I could change  i++ to ++i. The question is doing fixing just good form or in some cases it can make a difference in performance?  Meaning do the compilers I usually use: gcc and Visual C++ automatically make this optimization?  Information is also welcome about other well used compiles as well.

Is there a performance difference between i++ and ++i if the resulting value is not used?


I'm trying to take full backup using adb backup -all -f <path> and it took backup and stored in my PC.  When I try to restore it using adb restore <path> then it restores onto the target device.  ADB backup command is not taking backup of messages, contacts and pictures. Kindly guide me if I'm missing something.  I could see that I have to use adb root to take backup using pull command. Will the device warranty be there if I use adb root command?

I know I'm asking for the close-to-impossible -- as a real full-backup certainly requires root permissions. But still there are many folks around not wanting to root their devices -- afraid of voiding their warranties or bricking their devices, or just not having their devices supported by any rooting method.  I also know there were a lot of questions asked already on this topic, and I checked all of them having the backup tag -- none covers the entire topic, all just have pieces, and especially people new to Android (but other non-power-users as well) would have a hard time figuring out the best way.  So I want a detailed canonical answer to the question:  Not involving root-solutions, how to achieve a backup as close as possible to a full backup?  Please do not give simple one-liner answers like "Use app xyz [full-stop]." If mentioning an app (and I doubt a single app would be the answer here), include what parts are covered by it -- as well as ideas on how to fill the gaps it leaves. (And to make it absolutely clear: I know the first thing coming to mind is Titanium Backup -- I use it myself, but this does not apply here: This question is strictly about methods for non-rooted devices!) Moreover, the answer should be as generic as possible in terms of applying to a wide range of devices (i.e. it should not be restricted to one device or manufacturer).  I already mentioned having investigated all questions here tagged backup. These will certainly be helpful providing details for answers here, so I will list up the topmost ones concerning my question:            All these provide some details for my question (so feel free to get inspired by them) -- but I feel there are still details missing. Also it would be helpful to have a summary -- say, an answer including the full description of "the maximum possible".  A last criterium: While I'd consider cloud-based solutions legit, I'd favour local solutions. If you can provide both: all the better. But some people value privacy quite high (I'm one of them), and thus would not trust their data to some cloud service.    Thanks to Ryan, we now have a solution for a really complete backup of all apps and their data -- which I didn't dare to hope for! The only disadvantage: His solution only works for less than 10% of all Android users; namely those whose devices are running at least with Android 4.x.  So again, I ask the close-to-impossible: Any solutions applicable at least on Gingerbread (2.3.x) or, better, even Froyo (2.2.x) -- so they cover the majority of current devices? These solutions may involve multiple tools (try to keep it as simple as possible though; think of your mother to follow your instructions ;)  And keep in mind: NO ROOT!    To further motivate high-quality answers (and hopefully avoid low-quality ones), I will be a harsh one here: As I rarely do, I will down-vote answers not fitting the mentioned criteria on one end -- but on the other end, I will setup a bounty for the best answer (which cannot be done immediately, but earliest after 2 days).


In the past I succeeded to change the settings of mc in a way that I was able to copy and paste text from the internal editor (mcedit, entered with F4) by marking the text with the mouse like in the console or in nano and pasting it with right-click. How to set this up?

I use  editor over putty to edit files  I want to know how to copy text from one file, close it then open another file and paste it?  If it is not possible with Midnight Commander, is there another easy way to copy and paste specific text from different files?


please I'm confuse. I need your help. I want to find out if a carta soggiorno holder can travel to U.K. Without a visa whiles going with her spouse who holds Italian passport.

I have searched the internet but could not find specific information so if we have got the following document "Carta di Soggiorno di Familiare di Un Cittadino Dell'Unione" (Residence Card of a family member of a Union Citizen, Italy) issued by the Italian authority, what rights do we possess of working inside Italy and EU? What about travelling? Will we be requiring visas for the states which are are not in Schengen?


I have this cronjob.  50 15 * * * cd /var/www/html; for i in $(ls -d */); do tar zcvf ${i%%/}.tar.gz $i; done   But it shows me this.  /bin/sh: 1: Syntax error: Missing '}'   But when I run this command from command line directly, it works.  Where is the problem?  Thanks.

This is the script I use:  find /path/backups/ -type f -mtime -2 -printf '%P\n' | rsync -avz --progress --delete --exclude-from=- -e "ssh -p 512" /path/backups/ me@host:/remote/path/server-backups/   This is from the log:  > Jan 21 15:32:01 servername CRON[14654]: (serveruser) CMD (find /path/backups/ -type f -mtime -2 -printf ')   I've tried using cron.d, crontab -e and cron.daily. Both putting the script directly in the crontab file as well as calling a .sh script file. Any ideas how I would go about solving this?


It's hard to find a concrete information because everything is related to having a US visa, coming from or going to the US, which is not the case. We are leaving from Manila to Seoul, then to Addis Ababa and then to São Paulo, Brazil. Our layover length in Seoul is only 2 hours and 30 minutes. Is one of us required to have an airport transit visa?

I am a Vietnamese citizen. I am planning to buy a round-trip flight ticket from Taipei to Los Angeles (America) and I will transit in Seoul airport.   Do I need a visa if I want to enter Seoul (not over 72 hours)?   My first route is TPE-ICN-LAX, do I need a visa if I stay one night in Seoul? My second route is LAX-ICN-TPE, do I need a visa if I stay one night in Seoul?  Of course, I have a valid US visa, and onward ticket that I booked.


I'm following a YouTube tutorial on UV unwrapping the image of a mouth onto a character (  ), and although I've followed all the steps, several times, to a T, I cannot get the mouth image to show up on the character. I've included the blend file for your convenience. Could you please help me understand why this is not working?  Steps that I took:   Mark the seam. Unwrap the faces. Open the png mouth image. Create a new material that is a copy of the material used for the body. Add an image texture to that material. Assign the new material. When I use the file that he provides to go along with, the results are as expected. But when I do the same thing to my file, I do not get the same results.   Please, if you could take some time to help me I would very much appreciate it. Thank you.   Here is a copy of my file:   A copy of his file:    The png file used for unwrapping:

I'm tryning to apply a Texture Image to an object, but it don't work. I unwrapped the object and created the image in the UV/Image Editor. If i try to assign any other simple materials with just color, it won't work either. In the material preview it's showing nicely. As you can see   Thanks!


Based on what list of criteria or requirements does stackexchange.com create a subdomain site?  For example, they have   android.stackexchange.com apple.stackexchange.com & so on   I'm curious to know what is the list of criteria or requirements for Stack Exchange subdomains.   or   How do they decide to create a Stack Exchange subdomain site?  Also, apart from the first question, why haven't they created something like windows.stackexchange.com?

I have an idea or subject that should have a Q&A, and want to propose a new site. How can I do this?  Related:


In David Humes' book, "A Treatise of Human Nature" he states that reason is the slave to the passions.   "Reason is, and ought only to be the slave of the passions, and can never pretend to any other office than to serve and obey them. (T 2.3.3 p. 415)"  Could someone explain this to me, preferably reconstructing in a premise-conclusion format.   Many thanks.

I don't understand the meaning of this oft-quoted quotation of Hume's in On Reason, namely his saying that "reason is a slave to the passions."  What exactly does he mean by that ?  Is it simply that reason is subsequent to a deeper moral sense? Is it equivalent to the maxim today that "science cannot answer moral questions"? One thing that may be confusing is me is that I sense he's being somewhat rhetorical; would it be better to summarize his the arc of work that reason can only guide the passions, and that the truths we think it is uncovering us are ultimately a product of what our fickle passions urge it to investigate?


What is the difference between Left Join and Left Outer Join?

What is the difference between LEFT JOIN and LEFT OUTER JOIN?


1) Consider a gas expanding quasistatically and reversibly from $V_1$ to $V_2$ at constant temperature. I want to calculate the work done. So by convention work done by a system is a negative quantity but in my solutions I have  $$\delta W=p dV$$ Now $dV>0$ which would imply  that $\delta W >0$ which is confusing me. See I would have thought that it should be  $$\delta W= -p dV$$ so that $\delta W <0$.  2) Equally confusing is that in my notes I have that for quasistatic process $$\delta W=\mathbf{f} \cdot d\mathbf{x}$$ and it gives the examples of   (gas) $\delta W=-p dV$  (rubber band) $\delta W=\tau dL$  Why have we just taken $\mathbf{f}$ to be $-p$ for the gas and not $p$?  3) In the first step (isothermal expansion) of the Carnot engine explanation I have that the work done by the gas is $$W=\int^b_a p dV$$ Now as $dV>0$ this implies that $W>0$ but by convention I would have expected this to be negative?  4) In the same step of the Carnot engine as above but with a rubber band I have the work done by the system is  $$W=-\int^b_a \tau dL$$  but equally I cannot understand why we have a negative sign.

If a gas expands adiabatically will the work done be positive or negative?  I think it will be positive as $\delta W=p dV$ and we have a positive sign due to the work done by the gas is positive as it pushes to expand. But this site has the negative of the answer I obtain.   (See adiabatic processes section)


Find all solutions to $1!\times 3! \times \cdots \times (2n -1)!=m!$   I have found $(n,m)=(1,1),(2,3),(3,6),(4,10)$  How can one prove there are no more? Also is it a coincidence that these are the triangle numbers? If not, why is this so? I cannot work it out.

Find all natural numbers $n > 1$ and $m > 1$ such that $1!3!5!\cdots(2n - 1)! = m!$   I have been thinking about coming up with some inequalities which would narrow the possible range of pairs $(n, m)$, however the best I have been able to find so far are $m \ge 2n - 1$ and $m \lt n^2$, which is clearly not enough.  Update. The question has tag combinatorics as it is from a book about combinatorics, so there must be at least partly combinatorial solution.


I've places two tables side by side, but I can't get the labels right.  \begin{table}[ht] \begin{minipage}[b]{0.45\linewidth}\centering \begin{tabular} {l | l | l}         a & a & a         \end{tabular}         \label{tab:NotreDame}         \caption{Training on Yosemite dataset and testing on Notre-Dame dataset}         \end{minipage} \hspace{0.5cm} \begin{minipage}[b]{0.45\linewidth} \centering     \begin{tabular} {l | l | l}         b & b & b         \end{tabular}         \label{tab:Liberty}         \caption{Training on Yosemite dataset and testing on Liberty dataset} \end{minipage} \end{table}   When I compile my code, I get question marks instead of correct references.

\documentclass{article} \usepackage{algorithm}  \begin{document} \setcounter{section}{54} \section{A section with no label} \begin{algorithm} \label{myalg} \caption{An algorithm with the label `myalg'.} \end{algorithm} Reference to myalg: \ref{myalg}. \end{document}   With this code, the reference givens 55 (the section number); if I move the label after the caption command, I get the correct reference (1).  Why should this be the case? I find it confusing: when thinking about an algorithm as an environment, you expect to be able to label it right after you began it. At the very least I would expect some kind of error or "??" to appear, rather than the previous environment or reference-able entity being used.


How do I change the IMEI number of my iPhone?

I know changing the IMEI number of the phone, is illegal in most countries.  I'm basicly curious about two things:   Is that possible? If it is not possible; why is that so hard, technically? (Considering the fact that it is written somewhere in the phones memory.)


I am using Json parsing using Volley concept,I got null pointer Exception  this line "AppController.getInstance().addToRequestQueue(jsonObjReq);" please give a solution. thank you  JsonObjectRequest jsonObjReq = new JsonObjectRequest(Request.Method.GET,Allbooksurl, null, new Response.Listener<JSONObject>() {     @Override     public void onResponse(JSONObject object) {         try {             String result = object.getString("status");                             Log.d(result, "result");                             String message = object.getString("info");                             Log.d(message, "message");                             JSONArray responserecentbooks= object.getJSONArray("recentbooks");                             for (int i = 0; i < responserecentbooks.length(); i++)                             {                                 JSONObject person = (JSONObject) responserecentbooks.get(i);                                 String id = person.getString("id");                                 String name = person.getString("name");                                     db.insertValue(id, name);   }          } catch (JSONException e) {             e.printStackTrace();         }     } }, new Response.ErrorListener() {     @Override     public void onErrorResponse(VolleyError error) {         //VolleyLog.d(TAG, "Error: " + error.getMessage());         Toast.makeText(getApplicationContext(),         error.getMessage(), Toast.LENGTH_SHORT).show();     } });  try {     AppController.getInstance().addToRequestQueue(jsonObjReq);     } catch (Exception e) {     e.printStackTrace(); }

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


I know that this topic is already existed but, unfortunately, they don't solve my problem. My code is below  try {             String prID = txt_prno.getText();             HashMap hash=new HashMap(1);             hash.put("ProductID",prID);             InputStream file = getClass().getResourceAsStream("/myreports/reportpr1.jrxml");             System.out.println("path_1:"+file);             System.out.println("path_2:"+file.toString());             JasperDesign jd = JRXmlLoader.load(file);             JasperReport jr = JasperCompileManager.compileReport(jd);             JasperPrint jp = JasperFillManager.fillReport(jr, hash, conn);             JasperViewer.viewReport(jp,false);// jv = new JasperViewer(jp,false);         } catch (JRException ex) {             System.out.println(ex);         }   Here is my file structure   This is some error code from CMD.  It is a very long stack trace  java.lang.NoClassDefFoundError: org/apache/commons/beanutils/MethodUtils     at org.apache.commons.digester.CallMethodRule.end(CallMethodRule.java:632)     at org.apache.commons.digester.Rule.end(Rule.java:257)     at org.apache.commons.digester.Digester.endElement(Digester.java:1345)     at net.sf.jasperreports.engine.xml.JRXmlDigester.endElement(JRXmlDigester.java:199)     at java.xml/com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.endElement(Unknown Source)     at java.xml/com.sun.org.apache.xerces.internal.impl.xs.XMLSchemaValidator.endElement(Unknown Source)     at java.xml/com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanEndElement(Unknown Source)     at java.xml/com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(Unknown Source)     at java.xml/com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(Unknown Source)   This is the path of report file   Now, their is no more errors after I download and add the following file to my project library commons-beanutils-1.9.3-bin.tar.gz. But, this message appears instead of the error   net.sf.jasperreports.engine.JRException: Error compiling report java source files : C:\Users\IT\report32name_1548766294622_936064.java

I am getting a NoClassDefFoundError when I run my Java application.  What is typically the cause of this?


Hi I'm trying to figure out how to calculate the coordinates of a dot at a certain percentage point on an arc. Let's say the dot starts at (800, 300), the half-way points is (400, 0) and the end point is (0, 300). Let's say I want to calculate where the dot will be after traveling 25% of the arc. I'm really clueless where to start on this, thanks for your help.

Get the equation of a circle through the points $(1,1), (2,4), (5,3) $.  I can solve this by simply drawing it, but is there a way of solving it (easily) without having to draw?


My first language is not English and I have a question about a sentence that I recently saw. And I hope someone can help me.  Is it correct to say:  "I wish John were a myth so you could bust him."  instead of:  "I wish John was a myth so you could bust him."  And if both are correct, what are the difference between the two?

Possible Duplicate:          On a Tuesday morning, which of these sentences is the better way to express that I already want it to be Friday?     I wish it were Friday.   I wish it was Friday.


When I run cat /etc/group on Ubuntu 18.04, I get this output:    root:x:0: daemon:x:1: bin:x:2: sys:x:3: adm:x:4:syslog,singrium tty:x:5: disk:x:6: lp:x:7: mail:x:8: news:x:9: uucp:x:10: man:x:12: proxy:x:13: kmem:x:15: dialout:x:20: fax:x:21: voice:x:22: cdrom:x:24:singrium floppy:x:25: tape:x:26: sudo:x:27:singrium audio:x:29:pulse dip:x:30:singrium www-data:x:33: backup:x:34: operator:x:37: list:x:38: irc:x:39: src:x:40: gnats:x:41: shadow:x:42: utmp:x:43: video:x:44: sasl:x:45: plugdev:x:46:singrium staff:x:50: games:x:60: users:x:100: nogroup:x:65534: systemd-journal:x:101: systemd-network:x:102: systemd-resolve:x:103: input:x:104: crontab:x:105: syslog:x:106: messagebus:x:107: netdev:x:108: mlocate:x:109: ssl-cert:x:110: uuidd:x:111: avahi-autoipd:x:112: bluetooth:x:113: rtkit:x:114: ssh:x:115: lpadmin:x:116:singrium whoopsie:x:117: scanner:x:118:saned saned:x:119: pulse:x:120: pulse-access:x:121: avahi:x:122: colord:x:123: geoclue:x:124: gdm:x:125: hani:x:1000: sambashare:x:126:singrium nvidia-persistenced:x:127: rdma:x:128: docker:x:999:   I know that 'root', 'daemon', etc. .. are groups or user names, but what does the rest of that mean (:x:0:, :x:125:, :x:126:, ...)?

Similar to , but different result set, can anyone help me with the output of getent group?  It's something like this:  groupname:x:0:   just not sure what the x:0: signifies?


Which theoretical or experimental results provide us that we should calculate with massless gluon fields. Or in other words, what forbids gluons from having mass?

Earlier questions under a similar title referred to the short range of the strong force. My question is completely different. I'd like to know why gluons are considered massless in the Standard Model (regardless of the range of the strong force). For example, if mass is a result of the Higgs interactions, then why do gluons not interact with the Higgs boson? In addition to the theoretical reasons, is there any experimental evidence of gluons being actually massless? (I do realize that such experiments are not easy, because of the confinement.)  In the past, neutrinos were also considered massless, but not anymore. Is there a similar possibility for gluons to have perhaps a small invariant mass or is there an overriding reason for them to be definitely massless?  EDIT: The answer I've been looking for is deep in the comments below and not immediately apparent. To make it clear, I am repeating it here: To interact with a boson, a particle (the Higgs) must have a charge mediated by this boson. The Higgs has a weak charge and therefore interacts with the W and Z bosons thus giving them mass. The Higgs does not have the electric or color charge and therefore does not interact with the photon or gluons thus leaving them massless.


Not sure how to do this one I know it might have something to do with reduction formula but not sure where to go

Show that $$\int_0^\pi \sin^{2n} \theta d\theta=\dfrac{\pi(2n)!}{(2^n n!)^2} $$  So far I have came up with:  $$\sin^{2n} \theta = \left(\dfrac {z-z^{-1}}{2i} \right)^{2n}$$ and I know I should be using:  $$(a+b)^n=\sum_{k=0}^n \dfrac{n!}{(n-k)!k!}a^kb^{n-k}$$  but I'm not sure how to get the conclusion. Any help will be greatly appreciated.


I face the following     Here all  are appears below one by one. Actually I want, the last five are appears in the RHS of the first five. That is , how to align equally in the middle for a good look?  For this, I typed    \begin{enumerate}   \item $f:\Bbb R \to \Bbb R, x \mapsto \ln x$    \item $f:\Bbb R \to \Bbb R, x \mapsto [x]$   \item $f:\Bbb R \to \Bbb R, x \mapsto \frac{1}{x}$   \item $f:\Bbb R \to \Bbb R, x \mapsto \tan x$    \item $f:\Bbb R \to \Bbb R, x \mapsto \sqrt{x}$   \item $f:\Bbb N \to \Bbb Z, x \mapsto 5$   \item $f:\Bbb R \to \Bbb R, x \mapsto e^x$   \item $f:\Bbb N \to \Bbb N, x \mapsto 2^x$   \item $f:\Bbb R \to \Bbb R, x \mapsto \sin x$   \item $f:\Bbb R \to \Bbb R, x \mapsto x^2$   \end{enumerate}   Any help?

Is it possible to split an itemize list into several columns? (I'm sure it is, but I couldn't find a solution around here)  And additionally: Is it possible to automatically split a list into multiple columns if it reaches a certain item length?  so i want to display  item1 item2 item3   instead of   item1   item2   item3   while this should still happen  item1   item4 item2   item5 item3   item6


It's too big to be built in secret and it requires some maintenance all the time. A single man or even two or three people if you count Alfred and Robin can't keep up with everything.   Where are the workers who built it originally? All dead?  What if there is a leak from the lake?  Okay, it was built by workers who didn't know what they were building. But how they repair it?  By maintenance, I don't mean cleaning the floor or repairing a broken sink. Rather concrete reinforcement or construction/engineering work.

The batcave, in any version of Batman, is large.  Plus there's the batmobile, which required special construction, plus the batcomputer and numerous other batwidgets.  How did a good sized batcave get built without the land above it being torn up and without requiring a huge construction crew?  And, after the cave was built, how was the batmobile built in secret, without someone involved in it being able to make the connection between the car they built and the one that shows up in the news when Batman is first seen?  (While he's in Gotham, a masked vigilante is news that would end up nation wide.)  There would also be the need for secrecy so vilains can't find out how it is built and what the specs are.  And then there's the continual supply of batwidgets.  Just as with the batmobile, there's the need for these items and how they work to be kept secret.  It'd take several factories to produce all that Batman uses and major construction for any batcave I've seen (which is in movies and on TV).  How is all this done in secret?  (Or is there a trail of bodies?)


We (SFF.SE) sometimes use information from starwars.com site to answer questions.  As a random (well, latest) example, the article on .  This looks like "legitimate" source to me, since I assume that starwars.com is owned by Lucas Empire.  But I never actually ran into explicit confirmation on the canonical status of the facts cited in such pages.  Is there official confirmation of the canonicity (and canon level) of facts from starwars.com?   (I'm talking about "official" pages like Encyclopedia above, not random forums on the same domain).    To elaborate, what I am trying to ascertain is which of the following 3 situations is true:   starwars.com (encyclopedia) ONLY lists facts that are 100% taken from existing canon, with no guesses or additional wording that is not from canon. starwars.com (encyclopedia) may list some facts that don't come from existing canon, but any such new fact becomes canon (of level ???) as soon as it's stated on starwars.com, assuming it doesn't contradict existing canon Some of the explanations on starwars.com may include facts/wording that are merely someone's attempt to explain what we see in canon, but are in and out of themselves NOT canonical facts.  This last one is how Wookieepedia works. It does list facts from canon... but it ALSO lists facts that are made up by individual fans to explain small snippets seen in canon (but that include details NOT sourced from canon sources).  this is especially prevalent in G and T canon, where you have a visual from a movie/TV that doesn't contain great level of textual explanation attached to it, and therefore a Wikia article would build a narrative "explaining" the visual.

For all types of derivative works, namely:   Movies Novels Comic books Other written works (including RPG materials) Cartoons Video games Derivative movies (such as the infamous Ewok movies and even more infamous )   According to what rules does something become "canon" and who is responsible for the evaluation of a published work?


I want to know how this code#1 works so confusing... Can somebody explain how this gcd method returns something? public class GCDFinder {     //code#1     public int gcd(int a, int b) {         if (b == 0) return a;         return gcd(b, a % b);     }             public static void main(String[] args) {         System.out.println(new GCDFinder().gcd(4, 12)); // should print 5     } }  Meanwhile, I tried my own code using addition to understand this concept but I would get an error. public class Compute  {     public int gcd(int a, int b) {         if(b==0) {             return a;         }         return gcd(b,b+a);     } }

One of the topics that seems to come up regularly on mailing lists and online discussions is the merits (or lack thereof) of doing a Computer Science Degree. An argument that seems to come up time and again for the negative party is that they have been coding for some number of years and they have never used recursion.  So the question is:   What is recursion? When would I use recursion? Why don't people use recursion?


I was quite perplexed by a paradox that I thought of, for instance, say I am a person who completely understand einsteins field equations. In this case, Einstein formulated his theory. Now, say I have a time machine and I travel, back to the past and explained einstein the Idea of GR. So, Einstein wouldn't get to know about this Idea without me telling him.  So where is the information coming from? Is time travel to the past even possible?  Since, I was thinking about this, I could come up with no solutions and thought maybe time travel is not possible or there is a theory which already explains this situation.  So what does General relativity tell us about time travel to the past? Is it possible? and are the theories like may be the multiverse theory which can explain this phenomenon?  I know this is kind of related to the grandfather paradox, so there have to be theories since this is quite old right?

I read somewhere that according to relativity, it is possible - involving black holes and other stuff - to jump into the past. Is it possible for anything to go back in time either continuously or by jumping?


Has powered by ATI   CEFC and CT-ARP128B1-32M who makes it and amount of memory

I know of many ways to get a rough idea of my graphics card model. Here are two examples (instructions for Windows 7):  Method 1  1) Click start  2) Type dxdiag and press enter  3) Go to the Display tab and check the Name property.  Method 2  1) Click start  2) Right click on Computer and select Properties  3) Click on Device Manager  4) Expand the Display adapters to get a list of video cards  Problems  Unfortunately both these methods suffer from problems:  1) This is a very inaccurate measure. For example, if I have an ATI Radeon 4830, both methods will show that I have an ATI Radeon 4800 series i.e. there is no way to distinguish between different models within the 4800 series or any other series for that matter.  2) This is dependent on having the correct driver installed. If I have an incorrect driver installed, there is no way for me to find out what the correct driver should be.  Question  Is there any way for me to be able to determine the exact model of a graphics card without relying on having the correct driver installed. I realise there are ways to do this such as checking the documentation that comes with the computer or perhaps opening it up but I am interested in seeing if there is way of doing this with software.  Edit: Please note the requirements carefully. If the method relies on reading from the driver then it is ineligible.  If there is no program that can do this, is there a manual method? Some kind of website database etc?  Thanks!


Every application window has these numerical things instead of titles since I upgraded to Ubuntu 20.04:

I don't know what I did wrong in my Ubuntu 18.04 OS. For some reason some of my apps look like this:    This also happens to other gnome apps like pdf-reviewer and Logs. Window title, menu bar etc. are all blank, display only squares.  *Problem solved: I downloaded Google Fonts, saved them in a new folder, they can be applied system-wide, but after I did some font settings using Google Fonts it didn't work. I changed the font of Interface with Tweaks-Tool, that was what causing the problem.


Lets say I have a dataframe that looks like this:  groups <- floor(runif(1000, min=1, max=5)) activity <- rep(c("A1", "A2", "A3", "A4"), times= 250) endorsement <- floor(runif(1000, min=0, max=2)) value1 <- runif(1000, min=1, max=10) area <- rep(c("A", "A", "A", "A", "B", "C", "C", "D", "D", "E"), times = 100)  df <- data.frame(groups, activity, endorsement, value1, area)   printed:  > head(df)   groups activity endorsement   value1 area 1      1       A1           0 7.443375    A 2      1       A2           0 4.342376    A 3      1       A3           0 4.810690    A 4      4       A4           0 3.494974    A 5      3       A1           1 6.442354    B 6      1       A2           0 9.794138    C   I want to run a logistic regression (predicting endorsement from groups), but if you look at the area variable, A is very well represented, whereas B and E are not.  I'm not interested in the area variable itself, but the stats will be driven by areas that have high representation in the dataset, so I need to weight the data but I'm not sure the correct way to do it  This is the model I'd like to run:  library(lsmeans) model <- glm(endorsement ~ factor(groups), data=df, family=binomial(logit)) anova(model, test = "Chisq") lsmeans(model, pairwise ~ groups)   Without any adjustment, the "main effect" of groups and any pairwise differences will primarily be driven by any effects found in the most represented area (in the actual dataset area A has about 100x more subjects than any other area)  Whats the correct way to adjust for the unbalanced area representation? I thought about upsampling the minority groups (or even downsampling the majority group) but I feel like this would have adverse/artificial effects on the power of the test?

Okay, so I think I have a decent enough sample, taking into account the 20:1 rule of thumb: a fairly large sample (N=374) for a total of 7 candidate predictor variables.   My problem is the following: whatever set of predictor variables I use, the classifications never get better than a specificity of 100% and a sensitivity of 0%. However unsatisfactory, this could actually be the best possible result, given the set of candidate predictor variables (from which I can't deviate).   But, I couldn't help but think I could do better, so I noticed that the categories of the dependent variable were quite unevenly balanced, almost 4:1. Could a more balanced subsample improve classifications?


Today I was notified about a novel event regarding my reputation.    It appears a user account was deleted, whose question was answered by me and also up-voted. So 10+15(accepted)=25 was deducted from my account!    Why did I receive a penalty for that? Doesn't this rule discourage a user from providing answers?

Today my reputation was decreased because of 'User was removed' criteria.   First of all the information provided about this on the reputation page is quite inadequate.   It does not explain, who got removed?(Don't care about this) but I would like to know where my points got deducted on which question and would like some more detailed explanation for all the points awarded or deducted by SO, I always have to go hunting now what does this mean.  Can we have a better messaging system for reputation? The main reason I am writing this question is that found out from what "User was removed" means.      A user who voted for one of your posts had their account deleted   (either by choice or due to violating the network's Terms of Service).   As a result, all of their votes were undone, and the rep you gained   from them (or lost because of them) was revoked.   Some user broke the rules and got himself thrown out.    A user I am not associated with. A user I don't even know who he is. A user I have got nothing to do with.   Why am I getting punished for his acts?


An n×n matrix M of integers has the property that Mab=Mxy iff a+b=x+y. How many distinct elements are there in M?

An $n \times n$ matrix $M$ of integers has the property that $M_{ab} = M_{xy}$ iff $a+b=x+y$. How many distinct elements are there in $M$?


If $f_n$ is a sequence of functions over $[0, \pi/2]$ given by  $$f_n(x) = \frac {nx} {1+n\sin(x)},$$  then how would I go about proving that $f_n$ does not converge uniformly to a function $f$ on $[0, \pi/2]$?

Edit: the question had some missing details. It should read as follows:     Prove for all $a \in (0,\frac{\pi}{2}]$, $f_n \rightarrow f$ uniformly on $[a,\frac{\pi}{2}]$.  Here $$f_n(x) = \frac{n x}{1 + n \sin(x)}.$$   Here is my attempt at the problem:  If $x \in (0, \frac{\pi}{2}]$ then $| f_n(x) - f(x) |$  $$ =\left| \frac{nx}{1 + n\sin(x)} - \frac{x}{\sin(x)}\right| $$  $$ = \left|\frac{nx \sin(x) - x(1 + n \sin(x))}{[1+ n \sin(x)]\sin(x)}\right|$$  $$ = \frac{x}{\sin(x) + n \sin^2(x)} \leq \frac{1}{n} \space \space  \text{(is this line correct)}$$  So $\forall \epsilon > 0$, we may choose $N \geq \frac{1}{\epsilon}$ such that when $n \geq N \implies |f_n(x)-f(x)| \leq \epsilon \space \space \forall x \in (0, \frac{\pi}{2}]$  It's already been established that  $f_n(x)$ converges pointwise to: $f(x) = 0, x =0$ and $f(x) = \frac{x}{\sin(x)} ,x \in (0, \frac{\pi}{2}]$


First I installed KVM and Qemu on local machine to do some testing. Now I wanted to do so on a remote productive system. I can connect to the productive system from my laptop but not from local machine to remote productive system. The error message is:  Unable to connect to libvirt qemu+ssh://UserName@IpOfServer:Port/system.  Cannot recv data: Der Wert ist zu groß für den definierten Datentyp  Verify that the 'libvirtd' daemon is running on the remote host.  Libvirt URI is: qemu+ssh://UserName@IpOfServer:Port/system  Traceback (most recent call last):   File "/usr/share/virt-manager/virtManager/connection.py", line 1036, in _do_open     self._backend.open(self._do_creds_password)   File "/usr/share/virt-manager/virtinst/connection.py", line 144, in open     open_flags)   File "/usr/lib/python2.7/dist-packages/libvirt.py", line 105, in openAuth     if ret is None:raise libvirtError('virConnectOpenAuth() failed') libvirtError: Cannot recv data: Der Wert ist zu groß für den definierten Datentyp   I can login from local system via ssh to remote system,   libvirt-bin libvirt-clients libvirt-daemon  libvirt-daemon-system   is installed and my user is added to libvirt group but I can't get it to work.

Error message while opening VMM:     Unable to connect to libvirt.  You need to install openssh-askpass or   similar to connect to this host.


I've been trying to update the permissions so that I can run a command (specificially dotnet restore). I'm not sure if this issue is specific to running dotnet, or if it is more generic.  I can run the command using sudo dotnet restore, however I want to be able to run this command without sudo.  This is because I want to execute these commands via a CI tool (Jenkins), and I don't want that tool to have access to root commands. . The Jenkins user is unable to run dotnet restore (because of the errors below) or sudo dotnet restore (because it doesn't have root access).  When I run without sudo, I have the following errors from dotnet restore:  /usr/share/dotnet/sdk/2.1.104/NuGet.targets(104,5): error : Access to the path '/{file_path_to_project.csproj}/obj' is denied.  [{file_path_to_project.csproj}] /usr/share/dotnet/sdk/2.1.104/NuGet.targets(104,5): error :   Permission denied [{file_path_to_project.csproj}]   I've been trying to update the read and write permissions for my user on the /usr/share/dotnet/sdk/2.1.104/NuGet.targets file, and the {file_path_to_project.csproj} directory, but so far I still get the same errors.  Does it have something to do with the /obj directory? – When I run ls the obj file is not shown.  How can I update the permissions so that I can access these files without running sudo?  I created a /etc/sudoers.d/dotnet file to see if it would enable dotnet to be run without needing to call sudo.  I added the following contents:  {myusername} {myhostname} = (root) NOPASSWD: /usr/bin/dotnet. However, this still required me to run sudo before dotnet restore to get the correct output.

On one particular machine I often need to run sudo commands every now and then. I am fine with entering password on sudo in most of the cases.  However there are three sudo commands I want to run without entering password:   sudo reboot sudo shutdown -r now sudo shutdown -P now   How can I exclude these commands from password protection to sudo?


I use Ubuntu 16.04 LTS desktopand read and tested a lot of documentation about configuring an LDAP client on Ubuntu but can't get it to work.  Is someone can share his experience and give me some good and working documentation?  My goal:   Centralize authentication via LDAP (Ubnutu desktop -> Synology Directory Server (LDAP)) Mount /home share Mount other common shares

How to configure Ubuntu 12.04 as LDAP client with PAM modules?


I want to make an animation, like the deleting a note in iPhone Notes app. But here I want to do it for Tabbar. So deleting a view (something shows in a view) will swoop down in a delete tab bar icon. Say, I have favourite tab bar item, so adding something in the favourite will swoop down the view in the favourite tab bar item.

In my iPhone app, I have put a UIBarBUtton of type UIBarButtonSystemItemTrash in my UIToolBar. When pressed, I'd like to replicate the animation of Mail.app: the bin opens, the UIView folds and flies into it. Is there a way to access this animation ithrough the iPhone SDK?    Presently I am using a custom made animation, but there are some limits; for example, I cannot animate the bin itself. Do you have any suggestion? Code samples?  Cheers, Davide


Does the sum $\displaystyle \sum_{n=1}^\infty \left(\frac{n}{n+1}\right)^{n^2}$ converge?  I was given a hint to use the comparison test but fail to find a suitable series for comparison. I am not looking for a full solution but simply a convergent larger sequence for comparison.

Determine whether the series $\sum_{n=1}^{\infty}(\frac{n}{n+1})^{n^2}$ is convergent or divergent.  I've tried applying all the basic tests to no avail. I need to find out what the "trick" for this particular series is.


As I have started on learning rings, I saw the notation $\mathbb{Z}[i]$ was used in the context of '$\mathbb{Z}[i]$ is a commutative ring'. What does this notation mean? Is it complex numbers where the coefficients are integer values?

I was wondering what the notation $R[a]$ really stands for, if $a\in K$, where $K$ is a ring  and $R$ is a subring of $K$.  In my book they define $\mathbb{Z}[\sqrt2]=\{a+b\sqrt2|a,b \in \mathbb{Z}\}$.  So, my guess is that $R[a] = \{P(a)\mid P \in R[X]\}$. Since for $\mathbb{Z}[\sqrt2]$ this is the case, or is this just a coincidence?


I'm just beginning to learn Python 3 and am having trouble creating a list of strings from a file. Instead, it appears to be making a list of list. Each line of the text file is an element is the list. Each word is an element of a list within the first list.   I've tried google searches for creating lists from files and have read a couple of books on Python. I've also watched Udemy videos.  fname = input('Enter file name: ') try:    fh = open(fname) except:     print('File not found')     quit()  list1 = list() for item in fh:     list1.append(item.rstrip().split())  print(list1)   Actual Result:  [["I'm", 'using', 'this', 'file', 'as', 'an', 'example'], ['of', 'pulling',    'a', 'list', 'of', 'strings', 'from', 'a', 'file'], ['Rather', 'than', 'making',    'each', 'word', 'an', 'element'], ["it's", 'making', 'each', 'line', 'an', 'element']]   Expected Result:  ["I'm", 'using', 'this', 'file', 'as', 'an', 'example','of', 'pulling', 'a',   'list', 'of', 'strings', 'from', 'a', 'file', 'Rather', 'than', 'making', 'each',  'word', 'an', 'element', "it's", 'making', 'each', 'line', 'an', 'element']

What's the difference between the list methods append() and extend()?


In the following sentence , should locally owned have a hyphen?  A fun, causal way to sample the sights, stories and flavors of a cross-section of locally owned restaurants.

Which of these are acceptable? Is one preferable over the other?   "Chemically-deposited tourmaline is never periwinkle." "Chemically deposited tourmaline is never periwinkle."   Also, is the title to the this question asking what I'm trying to ask?  (I realize that there are other questions about hyphenation in similar contexts; I'm asking specifically about -ly adverbs.)


I'm a noob at Blender so that maybe the problem. I have Blender version 2.79. I rendered it a couple of times, but it still came out gray. These are screenshots taken before and after the render. (the first one is before, the second one is after)      Please help!!

A scene I made is not rendering, at all. This grey screen stays the same and nothing changes.  Here are my settings:  [


When I check any of mailbox from my server with a tool like this one:  I get:  SPF check:          pass DomainKeys check:   neutral DKIM check:         pass DKIM check:         pass Sender-ID check:    pass SpamAssassin check: ham   Seems OK.  My server IP is not blacklisted - I've checked it here:   All users in total do not send more than 50 emails a day. They're not spammers, just regular small business users.  Yet still there are problems with e-mail delivery to corporate addresses. Especially when I create a new domain, almost all e-mails from it will end up in spam. Or even worse: they are deleted without notice to sender or recipient.  Popular services like Gmail do not treat them as spam - problem is only with various corporate recipients.  What else should I check or do to put things right?

This is a  about how to handle email sent from your server being misclassified as spam.  For additional information you may find these similar questions helpful:                    Sometimes I want to send newsletters to my customers. The problem is, that some of the emails get caught as spam messages. Mostly by Outlook at the client (even in my own Outlook 2007).  Now I want to know what should be done to create "good" emails. I know about reverse lookup etc., but (for example), what about a unsubscribe link with an unique ID?  Does that increase a spam rating?


So I've been trying to find an answer on here that will work for my situation, but I am having a bit of a problem finding one. Basically, I have a table comprising 10,000 rows or more and there are some things that repeat in the table. For example, I have 3 units and they each have a unit_id that is repeating. These units also have a long/lat associated with them. How would I go about selecting the most recent long/lat of each unique device?  entry_id | unit_id | lat | long 1         123       45     62 2         123       15     24  3         123       12     11 4         456       55     31 5         456       01     12 6         123       15     46   The higher the entry_id, the newer the entry. So in this example I would want to select entries 5 and 6 so that I have the most recent lat/long for these devices. Any ideas?

My table is:     id home datetime player resource     1 10 04/03/2009 john 399   2 11 04/03/2009 juliet 244   5 12 04/03/2009 borat 555   3 10 03/03/2009 john 300   4 11 03/03/2009 juliet 200   6 12 03/03/2009 borat 500   7 13 24/12/2008 borat 600   8 13 01/01/2009 borat 700     I need to select each distinct home holding the maximum value of datetime. Result would be:     id home datetime player resource     1 10 04/03/2009 john 399   2 11 04/03/2009 juliet 244   5 12 04/03/2009 borat 555   8 13 01/01/2009 borat 700     I have tried: -- 1 ..by the MySQL manual:   SELECT DISTINCT   home,   id,   datetime AS dt,   player,   resource FROM topten t1 WHERE datetime = (SELECT   MAX(t2.datetime) FROM topten t2 GROUP BY home) GROUP BY datetime ORDER BY datetime DESC  Doesn't work. Result-set has 130 rows although database holds 187. Result includes some duplicates of home. -- 2 ..join  SELECT   s1.id,   s1.home,   s1.datetime,   s1.player,   s1.resource FROM topten s1 JOIN (SELECT   id,   MAX(datetime) AS dt FROM topten GROUP BY id) AS s2   ON s1.id = s2.id ORDER BY datetime   Nope. Gives all the records. -- 3 ..something exotic:   With various results.


I have a class with this function to provide a user language based on $user_id  function provide_user_language($user_id) {  return apply_filters('get_user_language',$user_id);  }   So in my script, I can simply get the user language by doing this:  $user_language=$this->provide_user_language($user_id);   But I need to associate this $user_language to a "set_current_language". I can do this by doing an add filter hook, but add_filter does not accept parameters. This is the add_filter line with the function itself but I don't know how to pass the $user_id or the $user_language so that set_current_language will be set to $user_language:  add_filter('set_current_language', array(&$this,'provide_user_language'));    I tried following this one but it won't work:    I appreciate any tips. Probably there is an easy way.

Is a way to pass my own parameters to the function in add_filter or add_action. For example take a look in the following code:  function my_content($content, $my_param) { do something... using $my_param here ... return $content; } add_filter('the_content', 'my_content', 10, 1);   Can I pass my own parameter? something like:  add_filter('the_content', 'my_content($my_param)', 10, 1)   or  add_filter('the_content', 'my_content', 10, 1, $my_param)


I am learning JavaScript and i came across this problem. I want to catch an input value using document.formName.elementName.valueand compare that value with an instance of an Array object.If the value exists it will throw an alert!.

What is the best way to find if an object is in an array?  This is the best way I know:    function include(arr, obj) {   for (var i = 0; i < arr.length; i++) {     if (arr[i] == obj) return true;   } }  console.log(include([1, 2, 3, 4], 3)); // true console.log(include([1, 2, 3, 4], 6)); // undefined