Just the mention of  or  makes gcc spit out an x86 error in compilation, what's this?

I'm fairly certain I'm doing something stupid.   But even so, I'm getting this compile error when compiling a very basic c++ script that connects to a node.js server using TCP. It crashes when there just the mention of a string being used -- anywhere. I don't mind using unsigned char arrays for communication, but the main c++ code I want to connect to the (local) server uses strings for other functions. Even when strings are not touching this part of the code it crashes in compilation (it compiles all files just fine, making you get your hopes up, and then says NOPE!). It seems like gcc doesn't recognize the string datatype on a very low architectural level or something like that. Maybe I'm using some deprecated method for TCP, maybe my mac is broken, but I'm not sure... Anyone seen this before?  compile error:  gcc   mainsocket.o   -o mainsocket Undefined symbols for architecture x86_64:   "std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::__init(char const*, unsigned long)", referenced from:       std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::basic_string<std::__1::nullptr_t>(char const*) in mainsocket.o   "std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::~basic_string()", referenced from:       _main in mainsocket.o   "std::terminate()", referenced from:       ___clang_call_terminate in mainsocket.o   "___cxa_begin_catch", referenced from:       ___clang_call_terminate in mainsocket.o   "___gxx_personality_v0", referenced from:       _main in mainsocket.o       Dwarf Exception Unwind Info (__eh_frame) in mainsocket.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation) make: *** [mainsocket] Error 1   barebones code:  #include <stdio.h>  #include <sys/socket.h>  #include <arpa/inet.h>  #include <unistd.h>  #include <string> //include <string.h>  #define PORT 1337   using namespace std;  int main(int argc, char const *argv[]) {       //errors when uncommented, compiles fine when commented (it doesn't even do anything)     string testmessage = "hello";      int sock = 0, valread;      struct sockaddr_in serv_addr;      char *handshake = "handshake";      char buffer[1024] = {0};      if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {          printf("\n Socket creation error \n");          return -1;      }      serv_addr.sin_family = AF_INET;      serv_addr.sin_port = htons(PORT);       // Convert IPv4 and IPv6 addresses from text to binary form      if(inet_pton(AF_INET, "127.0.0.1", &serv_addr.sin_addr)<=0) {          printf("\nInvalid address/ Address not supported \n");          return -1;      }      if (connect(sock, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0) {          printf("\nConnection Failed \n");          return -1;      }      send(sock , handshake , strlen(handshake) , 0 );      printf("Handshake sent\n");      valread = read( sock , buffer, 1024);      printf("%s\n",buffer );      return 0;  }


AIX Does not support bc boolean expression

I ran into an issue where bc does not have boolean expressions in the AIX system. Wondering if there is a replacement command so I don't have make my code any longer? This is in a bash script.   Here is what I had:  percent=-0.17 max=0.20 if [[ $(bc <<< "$percent <= $max && $percent >= -$max") -ge 1 ]]; then     echo "Under the $max acceptable buffer: File ACCEPTED"  else     echo "Over the $max acceptable buffer: File REJECTED"     exit 1 fi   This is my output:  ++ bc syntax error on line 1 stdin + [[ '' -ge 1 ]]


$f(0)=0$,$f(1)=1$,find the largest $u$ such that $\int_0^1|f'(x)-f(x)|dx \geqslant u$.

Suppose   $E=\{f\in C^1[0,1]$:  $f(0)=0$,$f(1)=1\}$.   Find the maximal $u\in \mathbb{R}$,such that forall $f\in E$,   \begin{align*} \int_0^1|f'(x)-f(x)|dx \geqslant  u. \end{align*}   I can prove that $u\geqslant \frac1e$,since \begin{align*} \frac1e=e^{-x}f(x)\Big|_0^1=\int_0^1e^{-x}(f'(x)-f(x))dx\leqslant \int_0^1|f'(x)-f(x)|dx . \end{align*} But I don't know how to find the  maximal $u$.


How to hide Dock icons from another Mac?

I have two Mac laptops logged into iCloud with same credentials. Now if I run e.g. Chrome then it will bring Chrome icon on the other laptop automatically. That's a good feature to share data/work between them, but how do I disable this feature or hide the icon? I'm running macOS Catalina 10.15.7.


If anonymity is so important, why is it not universal?

A frequent argument brought up in support of voting anonymity is that it can lead to potential grudges. Certainly the review system is of the same nature.  I cannot wrap my mind around the fact that voting is anonymous and reviewing is not. Either both should be public--and this would be fine since public reviewing has been successful--or both should be anonymous--and I assume this would be the desired option since this community holds anonymity so dear.  One could say that voting rates the posts, the actual meat of the site, while reviewing is based on clarifying the purpose of the site and cleaning it up.   answer makes the point that the community can trust that votes are a good measure of quality for the very reason that they do not know who cast them; the mentality that a high-ranking member may have supported something could blur the line between "science" and "politics/religion."  Reviewing, then, can be seen as a judgment of specific members rather than quality of edit/questions, which seems to fall precisely under the "politics/religion" umbrella--the review system is much more vulnerable to grudges due to this.  So let's discuss the differences and the implications of these disjointed anonymity policies.


This is  an easy Html.    <!DOCTYPE html> <html lang="en"> <head>     <meta charset="UTF-8">     <title>Title</title> </head> <body> <form method="POST" action="https://sm.ms/api/upload" enctype="multipart/form-data">     <input name="smfile" type="file">     <input type="submit" name="upload"> </form> </body> </html>     When i post an image to the server(third party) ,  the server(third party) returned the json  and changed my web..    {   code: "success",     data: {       width: 440,       height: 440,       filename: "timg.jpg",       storename: "5a7b1807506b2.jpg",       size: 11941,       path: "/2018/02/07/5a7b1807506b2.jpg",       hash: "m8FqIYBGWL1HDrT",       timestamp: 1518016519,       ip: "111.29.138.47",       url: "https://i.loli.net/2018/02/07/5a7b1807506b2.jpg",       delete: "https://sm.ms/delete/m8FqIYBGWL1HDrT"     } }     my question is how to POST this json to my background and how to don't change my  web ..


I always feel more afraid in the dark than in light conditions. Is this a common phenomenon in all the people? Does it have biological underpinnings?


If mass is invariant then why cant we travel faster than light?

I recently learned that relativistic mass isn't actually real or popular and that mass is actually invariant and not dependent on velocity. My entire sense of why we couldn't travel faster than light was because I thought that the faster we got the more massive we became. Now I'm lost and trying to understand why we can't travel faster than light.


I am wondering if one can use TeX/LaTeX to typeset a full-fledged fiction book i.e. a prose, literature (not poetry) e.g. if Conan Doyle wished to write his Sherlock using TeX, what would you have in mind for him? Is TeX even right for writing a book (non-mathematical, I repeat)? I have used TeX and still am using for Math, Physics and Economics to produce articles, monograph and theses but never a fiction/literature book. Naturally, I want to have a ready-to-go template adapted for the leading world publishers style, requirements etc.


Where do I ask a question about development, product management, UX design... when considering a career change towards software development?

I'm a professional completely OUTSIDE of the software development field, but I'm considering a career change in that direction.  I'm interested in learning about development, product management, UX design, and any other niche jobs in the field that I don't know about but might be suited for based on previous training/experience.   Where would I ask such a question?


Can a lens be too heavy for a given camera?

I currently own a Canon 200D and a friend of mine lent me a 24-70 F2.8 lens for playing around. The lens weighs 800 grams, which is double the weight of the camera itself. Putting it on I was slightly afraid of bending the lens mount if I hold the camera body without supporting the lens with my second hand.   Were those fears justified? Or can I safely mount any lens on any compatible camera without worrying about the weight?


Which variable to take as reference category?

I'm doing a research about the relationship between investment risk tolerance and demographic factors such as age, generation, survey year, and control variables (including education levels,...) and I have 2 questions:  I have already categorized respondents into 5 different groups ( loweduc, training, university, college, othereduc) but I'm not sure which one to take as the reference category. The data collected is from 1993 to 2019 and I'm doing the test to see if survey years affect their risk tolerance by adding event years and periods in the regression. For example, I want to see if 2001 and 2008 crisis affect their responses, and how they reacted in the next 4-year period. So I included 01, 08, 02-05, 09-12 to my model but I have no idea what is the reference category to interpret those dummies.


pass extra parameter jquery ajax file upload

I need to pass the loop index (i) to the xhr function so I can update the upload progress of each file.  for (var i = 0; i < files.length; i++) {     var file = files[i];                             var formData = new FormData();     formData.append('photos', file, file.name);      $.ajax({         url: 'index.php?option=com_photos&task=photos.uploadFiles',         type: 'POST',         xhr: function() {         },         success: function () {         },         data: formData,     });  }   SOLUTION:  I found out the answer of the question. To access the data param you need to use this.data etc..


How to have a figure with caption in multicol environment?

I am having the following problem with adding a figure inside the multicol environment:  \documentclass[10pt, twoside]{book} \usepackage{graphicx} \usepackage{subfig}  \begin{document}   \begin{multicols}{2}  a test file for picture inclusion along with the captions and labeling \begin{figure}  \centering  \includegraphics[width=5cma]{Cauchy_sequence_illustration-png}\\  \caption{Lets see}\label{pinki} \end{figure} \end{multicols}  \begin{figure}  \centering   \includegraphics[width=5cm]{Cauchy_sequence_illustration-png}\\  \caption{Lets see}\label{pinki} \end{figure}    \end{document}    After this while I am pressing Ctrl + Shift + X (usually I compile like this in DVI format and then clicking "dvi--->pdf" I convert it into PDF document.) the picture in multicol environment is not shown in YAP Viewer but the second one (which is outside of multicol environment) is shown along with the caption.  Kindly help me how to handle this problem. Please note that I am using the figure in .ps format. And I am not allowed to use any other format according to the instruction.


Can I Install Ubuntu On My tablet ZTE V9C?

Can I Install Ubuntu On My tablet ZTE V9C It has 275 mb of phone storage and 512mb of ram


I’m signed up for a first-year grad algebra class and the assigned textbook is Dummit & Foote. So I’m looking for another book or two that would go good with D&F.  Some qualities I’m looking for: (0) Begins with groups or categories (or semigroups or monoids), (1) Strong treatment of groups and representations of finite groups, (2) Strong treatment of noncommutative rings, (3) Doesn’t shy away from category theory, and (4) Covers some homological algebra.   Bonus points if it talks about Lie algebras and k-theory.   I’m not opposed to older or terse prose.   Oh, and I’m not a fan of Hungerford’s “Algebra.”  Edit: I am not looking for a category theory book. Nor am I looking for a book which covers everything completely through category theory. But I’d like it covered.


hey i'm working on a calculator and i have a little problem here i'm trying to make my calculator able to do some operations like (9*5)+4/8/(9-5) as example  i'm having some problems i thought that by stocking each value and operator in a linked list then trying to analyse the excepretion is a good way to solve that problem but i don't know what is exactly the problem i think there is an infiniteloop in my code  well that is the code . T0 and t are both TextFields  the same code goes for * and + and /   op ap = new op("+");     ap.addActionListener(new ActionListener() {         public void actionPerformed(ActionEvent e) {              cal.addLast(T0.getText());             cal.addLast("+");             oop = '+';             t.setText(t.getText() + oop);             T0.setText("");          }     });     ap.setBounds(256, 390, 80, 56);     getContentPane().add(ap);   that the = button  op ae = new op("=");     ae.addActionListener(new ActionListener() {         public void actionPerformed(ActionEvent e) {             cal.addLast(T0.getText());             T0.setText("");             do {                 searchpar();             } while (cal.size() != 1);             T0.setText((cal.get(0)));          }     });     ae.setBounds(256, 445, 80, 52);     getContentPane().add(ae);      public void searchpar() {     int i = 0;     do {         do {             if (cal.get(i) == "(") {                 paroind = i;                 paro = true;             }             i++;             if (i == cal.size())                 break;          } while (cal.get(i) != ")");         if (i == 0) {             searchmuldiv(0);             searchaddmin(0);         }          else {             parfind = i;             paro = false;         }          if (paro == true) {             searchmuldiv(paroind);             searchaddmin(paroind);         }     } while (i != cal.size() && cal.size() != 1); }  public void searchmuldiv(int i) {     do {         while (cal.get(i) != "×" && cal.get(i) != "÷") {             i++;             if (i == cal.size()) {                 i--;                 break;             }         }         if (cal.get(i) == "×") {              cal.set(i - 1,                     String.format("%2.f", Double.parseDouble(cal.get(i - 1)) * Double.parseDouble(cal.get(i + 1))));             cal.remove(i);             cal.remove(i + 1);             i--;         } else if (cal.get(i) == "÷") {             cal.set(i - 1,                     String.format("%2.f", Double.parseDouble(cal.get(i - 1)) / Double.parseDouble(cal.get(i + 1))));             cal.remove(i);             cal.remove(i + 1);             i--;          }      } while (i != 1 || i != (cal.size() - 1)); }  public void searchaddmin(int i) {      do {         while (cal.get(i) != "+" && cal.get(i) != "-") {             i++;             if (i == cal.size()) {                 i--;                 break;             }         }          if (cal.get(i) == "+") {              cal.set(i - 1,                     String.format("%2.f", Double.parseDouble(cal.get(i - 1)) + Double.parseDouble(cal.get(i + 1))));             cal.remove(i);             cal.remove(i + 1);             i--;         } else if (cal.get(i) == "-") {             cal.set(i - 1,                     String.format("%2.f", Double.parseDouble(cal.get(i - 1)) - Double.parseDouble(cal.get(i + 1))));             cal.remove(i);             cal.remove(i + 1);             i--;          }      } while (i != 0 || i != (cal.size() - 1));  }   i know that code won't calculate an expression with () and so but i'm going easily trying to fix it but it deosn't even calculate a simple expression as 1+1 and just a question which one is better to use in my case string.format or string.valueOf if there is a better waay to do that calculator than the linked lists so tell me (i'm new with java )


Unable to click Next button when sideloading an APK

First of all my device isn't rooted. I use this device for development purpose: installing apps using ADB, starting activity, and more. What has possibly gone wrong?  When I click on Next button nothing happens. But Cancel button works fine.  (Click image to enlarge)    It's LG G4 International version.


I removed my old password on my laptop, and when I opened it it asked for a password. I dont have a Windows 10 account so I dont have any means of opening it. Can anyone help?   Im using Asus K555L


Gears playing up after a chain replacement

I had used my bike for about a year and thought it was about time to replace the chain. The old chain started to skip links, but only sometimes.  I got the right chain from my local bike shop, I sized it up using my old chain, so it should have been the right length.  I put it on, however, now I got problems with shifting my gears (especially to lighter gears). Before the  chain replacement I didn't have problems with shifting between the gears.  It also sometimes skips links.  Does anyone know what might be the problem? Thanks, K


Does FAQ have official errata power in Pathfinder Society Organized Play?

According to FAQ,  and  traits don't allow their users to reduce spell level and have, say, a  Magic Missile as a 0 level spell (allowing to cast it at-will), or  Fireball as a 2nd level spell.   However, it has not been introduced as errata, and the text of those traits remains unchanged. Does this ruling presented in the FAQ have the official judgement power and change the way the feats work?   While any reasonable GM should definitely not allow such a cheese, I am asking from a point of Pathfinder Society Organized Play, where GMs have to play exactly as the rules say.


Electromagnetic Waves and Quantum Field Theory confusion?

If Electromagnetic waves are caused due to the vibrations in the electric and mutually perpendicular magnetic fields, and since according to QFT, particles are formed due to the vibrations caused in their respective fields. But which fields produce photons, because the vibrations in electromagnetic fields produce only EM waves?  Note :- I see there is one similar question that states - "How to introduce the electromagnetic field in Quantum Field Theory?" but the explanation as well as the question is totally mathematical, I want a rather simple interpretation of my question.


Prove reduction formula for $\int \cos^n (x)\sin^m (x) \, dx$

$$\displaystyle\int \:\sin^n\left(x\right)\cos^m\left(x\right)\mathrm  dx=\frac{\sin^{n+1}x\cos^{m-1}x}{m+n}+\frac{m-1}{m+n}\int \:\sin^nx\cos^{m-2}x\,\mathrm dx$$  I have been trying to solve for over a week now can someone please help me.


I have an Indian passport and a valid US visa. I have two stopovers in Frankfurt and Munich while going to India with Lufthansa. I have a change of flight in both places. Do I need an airport transit visa?


Problem with Non English(Farsi, ...) subtitle

When I want to see a movie or video in mac os x (with VLC, DivX Player, Quick Time) and want to load subtitles, these video player applications can't load my subtitle correctly show in strange text. My subtitle language is Farsi (RTL language). I must change some Unicode settings, but I don't know where anyone has any idea?


Question marks in citation? What is the solution besides compiling 4 times?

The problem of question mark in citation can be solved by compiling using Latex+Bibtex+Latex+Latex locally. However, it doesn't help when I submit the .tex file to a online editorial system of a journal. The conversion engine of the system can only do a single-time compiling so that the question marks are always there. The system only allows to upload .tex file, not supporting other types. Does anyone know any solution to this? Thank you!


Ubuntu 20.04: A Google Drive Client that works in 2020

I Have been doing some reading on google drive clients (that sync). Most applications / posts are outdated or very inactive. After comparing some i went for odrive & vgrive but both don't work.  odrive:  On first start pops up login for google but it complains that the browser is not secure enough (it is a web browser in the pop up itself)  vgrive:  I get it up and running and it seems to start syncing, but when i look at the files content its some error message that their are to many queries to the google api's and that for security reasons its blocked. Does anyone know how i can get them up and running or has a good and secure and free alternative? Also some alternative idea i had: Ubuntu has a build in mapping to google drive (not syncing) could i use a normal syncing tool that syncs this mapped folder with a normal folder? I would prefer to have a client software that does all the work.


Uses of a Virtual destructor in C++(other than desctruction order correctness)

Every C++ programmer knows that, virtual destructor is used to ensure the proper destruction order of objects in inheritance hierarchy.  Where else "Virtual Destructors" are used/can be used in realtime scenarios?


Time clock at the footline of a beamer slide is not adjusted in the middle if compiling with XeLaTeX

I'm adding a title clock in the foot line of a beamer slide, if I compile it with pdfLaTeX it works fine; while the clock doesn't align in the middle vertically if compiling with XeLaTeX. How can I fix this.  Here is my MWE:  \documentclass[10pt]{beamer} \usepackage[font=Times,timeinterval=1]{tdclock} \usetheme{Madrid} \title{Title} \author{Authors} \institute{Institute} \date[\initclock\tddate\ \ \tdtime]{\today} \begin{document} \frame{\titlepage} \end{document}


Record instantiation of java.lang.Throwable transparently

I want to implement an automatic exception logging service which collects all exceptions/errors that are thrown all over an application. The most elegant way would be to tap into either "throw" or the actual instantiation of the Throwable.  After several hours of research I came to following conclusions:   Somehow "tap into" "throw" is not possible Inject code with Instrumentation (or cglib) could solve the problem Extend the class loader and override the newInstance method could solve the problem   So far I think that option 2 would be the best choice but I fear that I am probably missing a much easier solution.


I was using Ubuntu LTS 20.04. I have countered many problems with this version of Ubuntu like Basic desktop actions are not available, etc.  So, I want to download a new and better version of Linux. Please suggest me best version of Linux which I should use, which have almost no such issues.


Prove that that the set $P = \{p\mid \text{Prime}(p) \land p \equiv 3 \pmod{4}\}$ is infinite

I was able to prove that there are infinitely many prime numbers but I'm not able prove that there are infinitely many primes that are equivalent to $3 \pmod{4}$. How do I go about doing this?


Is cardinal exponentiation strictly monotone in the exponent?

Let $\kappa$ be a cardinal, does $2^\kappa<2^{\kappa^+}$ always hold? It clearly holds if one assumes generalized continuum hypothesis, but does it also hold if one assumes otherwise?


Is the C# "explicit implementation" of the interface present in Java?

In C#, if you have two base interfaces with the same method (say, F()) you can use explicit implementation to perform different impl. for F(). This alloes you to differently treat the object, corresponding to the current point of view: as IMyInterface1 or IMyInterface2. Is this possible in Java?


What is the module/method used to get the current time?


Migrate question from chat to Stack Overflow / Programmers?

I recently searched for an answer to a programming question with Google. After the search did not turn up anything, I went to Stack Overflow chat and asked there, because it was more a question about which solution to a problem I had was best (that means I had a solution already, but wasn't sure if it was best).  After some discussion some alternate solutions came up that I liked better. I had the idea that it might be a good question / answer pair since that way it would be documented for future searching.  So, would it be OK to create a question / answer pair on SO just for reference? Or is it better to just forget about it? What is the SO policy? Does that belong more on Programmers?


Completely remove Ubuntu and partitions from Mac OS X Lion

I couldn't make the WiFi work on Ubuntu 12 after installing alongside OS X for a try. I tried everything and nothing worked, now I'd like to completely remove it since it's too complicated, is it safe to just remove the partitions it created?


file block size - difference between stat and ls

I've noticed that when I do a:  ls -ls file   It provides block count, say 8 blocks.  When I do:  stat file   I notice that the block count is 16, twice the number given by ls.   The block size on my file system is 4096. I learned that the arbitrary unit for blocks used by ls is 1024. Is it correct to say that stat uses an arbitrary unit of 512 bytes when reporting blocks?  If so, is there a reason for the inconsistency?  I'm running Ubuntu 11.10 on an ext4 file system.


What time did Monarch flight ZB7014 from Gatwick land in Rhodes on 2nd September 2015. It was due at 12 noon and we calculated our arrival as 3hrs 15 minutes late. Monarch airlines say it was only 2 hrs 45 minutes. The original plane had a technical problem and was withdrawn, the replacement aircraft from Prestige, a Spanish company blew a tyre on arrival which had to be replaced before we could finally take off.


Are there any references that the English language is written and read from left to right and from top to bottom?

What is the basis this? I have practically done hours of research and I couldn't find any source or reference about this.  I AM NOT ASKING WHY. I AM ASKING FOR A REFERENCE.


Controversial __set_task_state(tsk, state_value) macro syntax in linux kernel

I came across this syntax in several macros, in linux kernel 2.4.31 files, but to keep things in focus I am asking regarding __set_task_state(tsk, state_value) macro defined in include/linux/sched.h: #define __set_task_state(tsk, state_value)      \     do { (tsk)->state = (state_value); } while (0)   What is the "advantage" of defining the above macro with the do while(0) statement ? Any side effects ? It's more convenient to define it like so : #define __set_task_state(tsk, state_value)  (tsk)->state = (state_value)


Datepicker how to exclude days in a week?

How to prohibit the choice of days off (sа, su)?    $( "#datepicker" ).datepicker({  firstDay: 1,   minDate: 5, }); <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.js"></script> <script src="https://code.jquery.com/ui/1.12.1/jquery-ui.js"></script> <input type="text" id="datepicker">


Cheap/free tool to view/convert Canon CR2 RAW format photo files on Windows?

Recently, my family had some professional photos taken while vacationing at a resort.  The photos were given to us on CD in both .CR2 and .jpg formats.  While we can view the JPEG-format versions of the photos just fine, they had some effect and color filters applied which we'd rather not have for some prints.  Consequently, I'd like to open the .CR2 files myself to get at the original unmodified photos.  I don't own a recent Canon camera, so I don't have the corresponding Canon software that undoubtedly ships with their RAW-capable cameras.  I tried Corel Paint Shop Pro X2, but it didn't recognize the .CR2 files.  So, what is a cheap or free tool to view and convert .CR2 photos on Windows?  Note: I don't want to buy Adobe Photoshop.  I trust it would work, but I'm seeking a cheap or free solution, at this point... I'm not yet enough of a photo addict to buy expensive pro tools.


Group theory question. If $m$ and $n$ are relatively prime, and $a$, $b$ belong to group and $a^m = b^m$ and $a^n = b^n$, how would one prove $a = b$?

How would you prove that 2 elements of the group $G$ are equal, i.e., $a = b$ if we know that $a$, $b$ belong to group $G$ and that $m$, $n$ are relatively prime (integers) and that $a^m = b^m$ and $a^n = b^n$  Thanks!


Why does Ubuntu Download recommend 32-bit install?

Update for 13.10: 64-bit version is now the default and 32-bit is labelled "for machines with less than 2GB RAM" The Ubuntu desktop download screen has a pair of radio buttons you use to select whether you wish to download the 32-bit or 64-bit version.  The 64-bit version is labeled "Not recommended for daily desktop usage."  If you have a 64-bit processor, why would you not want to use the 64-bit version of Ubuntu? Update for 10.10: They've removed the "Not recommended" label from the 64-bit version and added a "Recommended" label to the 32-bit version. Update for 11.04: Same as 10.10. Update for 12.04: Still says "Recommended" next to 32-bit version of desktop Update for 12.10: 32-bit version of desktop is still default, says "recommended" Update for 13.10: 64-bit version is now the default and 32-bit is labelled "for machines with less than 2GB RAM"


In our application we define variables starting with "${" followed by variableName and a closing "}". But the following versions does not work: <xs:pattern value="\$\{*\}" /> <xs:pattern value="[${]*\}" /> I think i did not escape the $ s properly, but did not find out how to do it.


Two objects right next to each other, but wildly different coordinates

Can someone explain why the coordinates on these two objects are so drastically different? The Y direction, which is UP/DOWN in this view, should be the same between these two objects.  But they differ by 1000. I figure that this must have something to do with the object that I have both of these objects parented to.  It is a reference which I sometimes move between location Y=0 and Y=1000.  Perhaps I added one object while the parent was at Y=0, and another when it was at Y=1000, but it seems like the coordinates should change when the parent does, or they should remain fixed to the parent's coordinate system.  But this is just...baffling. How do I fix this?   EDIT: Here is a simple blend file showing the issue. The cubes are named "Parent", "Child 1", and "Child 2". They all started out on the X axis, 5 meters apart. I parented "Child 1" to Parent. Then I move Parent and Child 2 up by 10 meters on the Y axis.  Child 1 followed along, because it's parented to Parent 1. I then parented Child 2 to Parent. Now when you click on Child 1, the Y coord is 0.  On Child 2, the Y coord is 10.


I've been thinking about a distribution of charge that does not follow Maxwell's euations, and I can't understand what's wrong with my reasoning. If we have a constant distribution of charge $\rho(x,y,z)=\rho_0$ in all space then we have $\vec\nabla\cdot \vec{E}=\rho_0/\varepsilon_0$. But the charge' symmetry implies that $\vec{E}=(0,0,0)$ in all of space (it as to be the same after a translation or a rotation), so $\vec\nabla\cdot \vec{E}=0$. Can someone help me?


Suggested edit incorrectly attributed to me

There was a  that collided with an edit by the OP. The OP had added information to the question, but the suggested edit was missing this, so in the comparison it was like the edit removed this part.  I wanted to approve the suggested edit and also improve it by re-adding the missing part. Meanwhile, the suggested edit had been rejected by 3 people. As a result, the things changed by the suggested edit are now attributed to me.  Either the suggested edit should have been included in the revision history anyway, or it shouldn't be possible for 3 people to reject it while someone else is improving it.  (The question has also been removed now, so it's 10k+ to view it I believe)


Link an external CSS file to a JavaScript File

I need to link an external CSS file into a JavaScript file i am working on.  Obviously to link one into HTML you would use:  <link rel="stylesheet" href="css/style.css">   But what is the JavaScript equivalent?


I'm trying to calculate: $$\lim_{n\to\infty}\frac{n!}{n^n}$$ I'd guess it's $1$ as the degree of the denominator and numerator would be $n$ and their coefficients would be $1$ as well.  If it's $1$, then: $$\sum_{n = 1}^\infty \frac{n!}{n^n}$$ Would be divergent from the divergence test. The issue with this is I know that this sum is convergent, but the limit still seems like it should be $1$.


Proper automount on systemd Linux systems

What is the proper way to do a boot/hot-plug automount for ATA and USB storage devices on Linux systems using systemd without requiring a GUI or a user having to be logged in?  It seems that calling mount from a udev rule is  with systemd (so  are no longer guaranteed to work), and udisks does not automount if the user is not logged in locally.  The method should have a way to include mount options, so writability and filesystem masks can be set, as well as clean up after an "ungraceful" unmount (i.e., yanking the device out while still in use).    NOTE: This is a similar question , but that question concerns a specific use case on Debian systems. This question is for all Linux systems using systemd.


We have a user here who uses Word 2003 and Excel 2003 as his primary tools. He needs to keep different versions of his files over the time so he can rollback to a previous version at any time. Currently, every time he feels like a new version is needed, he uses "Save as..." and creates a copy of the document. He wants to get rid of all these files and wants to keep a single file, but he wants access to the history of his documents.  The initial request was to install a version control system (like SVN) on the user's machine and create a reposity for him on our server, but that involves coaching and supporting him if problems arise. We would like him to be as autonomous as possible without too much intervention on our side.  Then I read about Word having a version manager built-in, which allows to save multiple versions of the same document, and go back to any version at any time you wish. Eureka! The problem was solved, but then I opened up Excel to check if the same functionality exists and I was very disappointed when I clicked the File menu and did not find the Versions element.  I wanted to know if there is such a feature in Excel 2003 ? Or maybe in a newer version ?


Let $f$ be a continuous function at $x_0$ and differentiable in the neighborhood of $x_0$. If $\lim_{x\to x_0}f'(x)$ exists, then $f$ differentiable at $x_0$ and $f'(x_0)=\lim_{x\to x_0} f'(x)$. It might be a classic result, but I didn't really find the post here using MVT. If someone could give a feedback on my proof, I would really appreciate it. Thank you in advance.  First of all, as $f$ is differentiable in the neighborhood of $x_0$, then there exists $\delta>0$ such that $f$ is differentiable on $]x_0-\delta,x_0+\delta[$. Consider an interval $[x_0, x]$ with $x \in ]x_0,x_0+\delta[$. $f$ is continuous on $[x_0,x]$ (because differentiable in the neighborhood of $x_0$ and continuous at $x_0$) and differentiable on $]x_0,x[$. Let  $\lim_{x\to x_0}f'(x)=L\in \mathbb{R}$ Then, by MVT, $\exists c_x \in ]x_0,x[$: $f(c_x)=\frac{f(x)-f(x_0)}{x-x_0}$ $\implies$ $\lim_{x\to x_0}f'(c_x)=L=\lim_{x\to x_0}\frac{f(x)-f(x_0)}{x-x_0}=f'(x_0)$ as wanted. So,   $f$ differentiable at $x_0$ and $f'(x_0)=\lim_{x\to x_0}f'(x)$. I'm not really sure about my definition $x$ (it's domain). I think that it is not well defined. I could have passed by another definition of derivative and use the limit as $\delta\to 0 $, but I didn't really find how to define correctly my interval.


How can I scrape specific data from a website

I'm trying to scrape data from a website for research.  The urls are nicely organized in an example.com/x format, with x as an ascending number and all of the pages are structured in the same way. I just need to grab certain headings and a few numbers which are always in the same locations. I'll then need to get this data into structured form for analysis in Excel.  I have used wget before to download pages, but I can't figure out how to grab specific lines of text.  Excel has a feature to grab data from the web (Data->From Web) but from what I can see it only allows me to download tables. Unfortunately, the data I need is not in tables.


Is these usage habits leading my MacBooks result to battery bulge?

I have a Macbook Air and two Macbook Pros. All of their batteries got a bulge.  I like to use them in this way:   Always plugged to the power if there is one. 95% of the time, I plugged it to power. I do this because I think when power is on, the software runs fast. Never restart the OS. I do this because I think it saves me a lot of time waiting for the system to restart (even though it doesn't take much) Never shut down the machine, if I need to take the device, I just fold the screen (if not connecting to an external display) 70% of the time, I use an external display and fold the screen when using it. I do this because I like to put my keyboard on the top of the MacBook, so this would save a lot of space.   I hope to get some advice that which one (or more) of the above habits are causing the battery bulge.


could not exec dpkg! e: sub-process /usr/bin/dpkg returned an error code (100) - I cant fix it

I have tried installing PHPMyAdmin via terminal by using the next command: sudo apt-get install phpmyadmin, the results of the terminal are as shown:  > root@ns382469:~# apt-get install phpmyadmin Leyendo lista de > paquetes... Hecho Creando árbol de dependencias Leyendo la información > de estado... Hecho Se instalarán los siguientes paquetes extras:   > dbconfig-common libltdl7 libmcrypt4 php5-mcrypt Paquetes sugeridos:   > libmcrypt-dev mcrypt www-browser Se instalarán los siguientes paquetes > NUEVOS:   dbconfig-common libltdl7 libmcrypt4 php5-mcrypt phpmyadmin 0 > actualizados, 5 se instalarán, 0 para eliminar y 0 no actualizados. > Necesito descargar 6.441 kB de archivos. Se utilizarán 17,5 MB de > espacio de disco adicional después de esta operación. ¿Desea continuar > [S/n]? S Des:1 http://debian.mirrors.ovh.net/debian/ wheezy/main > libltdl7 amd64 2.4.2-1.1 [352 kB] Des:2 > http://debian.mirrors.ovh.net/debian/ wheezy/main libmcrypt4 amd64 > 2.5.8-3.1 [83,2 kB] Des:3 http://debian.mirrors.ovh.net/debian/ wheezy/main dbconfig-common all 1.8.47+nmu1 [487 kB] Des:4 > http://security.debian.org/ wheezy/updates/main php5-mcrypt amd64 > 5.4.39-0+deb7u2 [16,1 kB] Des:5 http://debian.mirrors.ovh.net/debian/ wheezy/main phpmyadmin all 4:3.4.11.1-2+deb7u1 [5.503 kB] Descargados > 6.441 kB en 0seg. (8.520 kB/s) Preconfigurando paquetes ... Could not exec dpkg!  E: Sub-process /usr/bin/dpkg returned an error code (100)   Note: My system is set to Spanish Language.  When I try to install somethink I have this same error when running the sudo apt-get install command.  Edit  After following Geppettvs D'Constanzo advice on permissions on dpkg I receive this in the terminal:  Root@ns382469: ~ * chmod 755/usr/bin/dpkg chmod: it is not possible to accede to "/usr/bin/dpkg": the file or the directory does not exist   Any help is appreciated.


How can I call command line commands from python

How can I use command line tools like ls, grep from python.


Is there a way to make hand painted designs glow?

If not, what’s an easy way to model more intricate designs anyway, here is a crudely drawn example of what i want


Is Ubuntu Desktop compatible with Acer Aspire hardware

Does anyone know if Ubuntu Desktop 13.10 is compatible with the Acer Aspire ATC-605-UB11.  This system has the following specs:  Intel processor = i5-4440  Memory = 8GB RAM  Hard Drive Capacity = 1TB  This system also has a specific graphics card.  Appreciate anyone who can answer this A.S.A.P.  Thanks in advance...


What would be the quickest way to construct a Python binding to a C or C++ library?  (I am using Windows if this matters.)


Is there a replacement for WUBI in Windows 10?

I used to have Xubuntu 11.10 side-by-side with my Windows installation, installed via WUBI from Windows. After upgrading to Windows 10, however, this doesn't start any more, so I wanted to reinstall it.  However, I have noticed that WUBI is not included on the new 15.10 Xubuntu iso, and is also generally not supported any more.  Is there any way I can achieve what I had before, without partitioning my hard disk?


Best way to remove bytes from the start of a file?

Today I had to remove the first 1131 bytes from an 800MB mixed text / binary file, a filtered subversion dump I'm hacking for a new repository. What's the best way to do this? To start with I tried dd bs=1 skip=1131 if=filtered.dump of=trimmed.dump  but after the skip this copies the remainder of the file a byte at a time, i.e. very slowly. In the end I worked out I needed 405 bytes to round this up to three blocks of 512 which I could skip dd if=/dev/zero of=405zeros bs=1 count=405 cat 405zeros filtered.dump | dd bs=512 skip=3 of=trimmed.dump  which completed fairly quickly but there must have been a simpler / better way? Is there another tool I've forgotten about?


Can I trust a hard drive that has had to reallocate sectors?

I ran this HD utility called  that displays some of the S.M.A.R.T. information on my drives.  It is displaying a "Caution" warning on one of my drives because its "Reallocated Sectors Count" value is 263 (ideally it should be 0 as it is on all of the other drives I have tested).  I posted this question on another forum and the general consensus of the responders was to back up immediately and get rid of the drive.  The drive is fairly new and only has 4575 hours on it.  I just learned about this utility a few weeks ago, so I don't know when the reallocation of these sectors may have occurred, but it hasn't changed.  Can I trust this drive?    Update (9/27/2009): That reallocated sector count stayed at 293 until about a week ago when I noticed it went up by 1.  Just yesterday, I noticed it's up to 659.  It's under warranty and is going back to the manufacturer for replacement.


How to update/upgrade Ubuntu Server 16.04 offline ?. I have created a local mirror (150GB) using apt-mirror.  How to configure offline server/system to update the system.   Thanks in advance


In Ruby on Rails, how do I format a date with the "th" suffix, as in, "Sun Oct 5th"?

I want to display dates in the format: short day of week, short month, day of month without leading zero but including "th", "st", "nd", or "rd" suffix.  For example, the day this question was asked would display "Thu Oct 2nd".  I'm using Ruby 1.8.7, and  just doesn't seem to do this.  I'd prefer a standard library if one exists.


how to make a full backup of ubuntu server for another computer?

I have a Ubuntu 15.10 server, which currently has a bunch of software installed on. Now, I want to make a full backup of everything there (including profiles, configs, etc...) on this computer (virtually on Parallels Desktop) for another physical computer which I've recently installed Ubuntu 15.10 server on it.  So how can I transfer this system completely into that computer? I tried PinguyBuilder and Systemback, but they were not what I wanted.  Considering that if there is a way, which would need not or at least a Internet connection (specially on physical computer) would be awesome.  Any help?  P.S: I know there are many topics for backup things, but they are not exactly for a non-gui server, or maybe I couldn't find what is suitable for me.


Is there a single word for 'without a beginning'?

Is there a single word for: something that has no beginning or without a beginning


How to clone array of object by value and not by reference in javascript

I am having trouble to copy an array of objects using Lodash.   Please see the code,   var freshSlots = _.clone(this.bookingSlots); console.log(freshSlots) // It prints the new changed copy this.bookingSlots=this.bookingSlots[0].booked=true // here I am running some loops and changing the property values of this.bookingSlots   As you can see, this cloning is happening by reference that's why I never get the old copy. How can I get the old copy by values?   Thank you.


Call button click event on pressing Enter - c#

I am new to c# - I want to trigger button click event on pressing enter. My code not working properly -   issue is that when i press enter on submitting some value, it displays messagebox which it should show but on pressing Enter for OK button of Messagebox, it automatically triggers button click event again even i don't press enter or enter any other value.    public partial class Form1 : Form {     int n1, n2 = 0;     private static readonly Random getrandom = new Random();     private static readonly object syncLock = new object();     public int GetRandomNumber(int min, int max)     {         lock (syncLock)         { // synchronize             return getrandom.Next(min, max);         }     }      public int tQuestion()     {         n1 = GetRandomNumber(2, 11);         n2 = GetRandomNumber(2, 11);          string tQues = n1 + " x " + n2 + " = ";          label1.Text = tQues;          return 0;     }       public Form1()     {         InitializeComponent();     }      private void Form1_Load(object sender, EventArgs e)     {          tQuestion();      }      private void label1_Click(object sender, EventArgs e)     {      }      private void textBox1_TextChanged(object sender, EventArgs e)     {         textBox1.KeyDown += new KeyEventHandler(tb_KeyDown);     }      public void button1_Click(object sender, EventArgs e)     {          string tAns = textBox1.Text;         int answer = n1 * n2;          string tOrgAns = answer.ToString();          if (tAns == tOrgAns)             MessageBox.Show("Your answer is Corect", "Result", MessageBoxButtons.OK,MessageBoxIcon.Exclamation );         else             MessageBox.Show("Your answer is WRONG", "Result", MessageBoxButtons.OK, MessageBoxIcon.Stop);         textBox1.Text = "";         textBox1.Focus();         tQuestion();     }      static void tb_KeyDown(object sender, KeyEventArgs e)     {         if (e.KeyCode == Keys.Enter)         {             button1_Click(sender, e);         }     }   Moreover, code only works if i remove static from static void tb_KeyDown(object sender, KeyEventArgs e) - otherwise it gives error:      An object reference is required for the non-static field, method, or   property   Please help me - i am new to c# & .Net


I'm a beginner coder in a high school environment. I'm currently an AP Computer Science A student, and I have an in-class project to create a "fun" activity. I was trying to make a Card and Deck class in order to create different games with it, but I keep getting a NullPointerException run-time error from what I believe is in the Deck class. Can someone point me in the direction of why my code is behaving this way? The two classes are below. Thank you!    public class Card{   private String suit, color, name;   private int value;    public Card (){     suit = "Diamond";     color = "Red";     name = "One";     value = 1;   }    public Card(String n, String s, String c, int v){     suit = s;     color = c;     name = n;     value = v;   }    public String getSuit(){     return suit;   }    public void setSuit(String s){     suit = s;   }    public String getColor(){     return color;   }    public void setColor(String c){     color = c;   }    public String getName(){     return name;   }    public void setName(String n){     name = n;   }    public int getValue(){     return value;   }    public void setValue(int v){     value = v;   } }     public class Deck{   private Card[] decks;    public Deck(){      decks = new Card[52];     for (int i = 0; i<52; i++){       if(i<26){         decks[i].setColor("Red");       }       else{         decks[i].setColor("Black");       }        if(i<13){       decks[i].setSuit("Diamond");       decks[i].setValue(i+1);       }       else if (i<26){       decks[i].setSuit("Heart");       decks[i].setValue(i-13+1);       }       else if (i<39){       decks[i].setSuit("Spade");       decks[i].setValue(i-26+1);       }       else{       decks[i].setSuit("Clover");       decks[i].setValue(i-39+1);       }      }      for(int i=0; i<52; i++){       if(decks[i].getValue() == 1){         decks[i].setName("Ace");       }       else if (decks[i].getValue() == 11){         decks[i].setName("Jack");       }       else if (decks[i].getValue() == 12){         decks[i].setName("Queen");       }       else if (decks[i].getValue() == 13){         decks[i].setName("King");       }       else{         decks[i].setName(changeName(i));       }     }   }    public String changeName(int value){     if (value == 1)       return "One";     else if (value == 2)       return "Two";     else if (value == 3)       return "Three";     else if (value == 4)       return "Four";     else if (value == 5)       return "Five";     else if (value == 6)       return "Six";     else if (value == 7)       return "Seven";     else if (value == 8)       return "Eight";     else if (value == 9)       return "Nine";     else       return "Ten";   }    public void swap(Card[] d){     int rand = (int)(Math.random()*26 + 1);     int rand2 = (int)(Math.random()*26 + 27);     Card temp = decks[rand];     d[rand] = d[rand2];     d[rand2] = temp;   }      public void shuffle(){     for(int i = 0; i<26; i++){       swap(decks);     }   }    public Card getCard(int n){     return decks[n];   }    public int getValue(int n){     return decks[n].getValue();   }    public String getName(int n){     return decks[n].getName();   }    public String getSuit(int n){     return decks[n].getSuit();   }    public String getColor(int n){     return decks[n].getColor();   }    public Card[] getDeck(){     return decks;   } }


I am currently studying electrodynamics with all the fields and the like. Now, as I understand it, in a more modern viewpoint there is a duality between electromagnetic fields and photons, with photons being the particles that are exchanged in the process of interaction.  My question is, what is the current explanation to what an electromagnetic field is? For example, consider a point charge $q_1$. In order for another charge $q_2$ to 'feel' $q_1$, there is an electromagnetic field generated by $q_1$ that allows interaction. However, using the photon picture of view, a charge should then constantly radiate photons in all possible directions to let other charges know that it's here and should be interacted with. This leads to a problem in energy conservation, as each photon carries an energy $h\nu$, and thus even if a charge is at rest it would radiate off its energy and subsequently be gone.  How can this be resolved? What is the real connection between an electromagnetic field and photons?


What do you call a person who is your friend only because you benefit them?

Looking for a word to describe a person who only makes friends to benefit themselves.


Can overcharging destroy Xperia J or Android phone?

My phone needs to charge for about only 2 and half hour, but I forgot so I charged my phone for about 3 and half hour. Then I noticed that my battery is easy to drain. When my phone is in 14% or below, it will tell me that I already need to charge but when I turn off my phone and turn it on again, it will go back to 16%. Also when my phone is already 100% charged and I turn it off and on again, it will be at 95% left. Can overcharging destroy a Xperia J or Android phone?


open resource with relative path in Java

In my Java app I need to get some files and directories. This is the program structure: ./main.java ./package1/guiclass.java ./package1/resources/resourcesloader.java ./package1/resources/repository/modules/   -> this is the dir I need to get ./package1/resources/repository/SSL-Key/cert.jks    -> this is the file I need to get  guiclass loads the resourcesloader class which will load my resources (directory and file). As to the file, I tried resourcesloader.class.getClass().getResource("repository/SSL-Key/cert.jks").toString()  in order to get the real path, but this way does not work. I have no idea which path to use for the directory.


Converting FAT32 to NTFS without formatting (server 2008)

I have a FAT32 partition in windows server 2008 machine. How can I convert the partition to NTFS without formatting?     My intention is to resize the partition and add some     P.S.  exits with errors on server 2008.


How do I divide my root partition into two partitions?

I have been using Ubuntu 17.04 and it's the only operating system on my 500 GB hard-drive. I have only one partition (i.e root partition). Now I want to go back to 16.04 LTS but I want to keep my existing data intact so I want to create an additional partition to store my data(movies and the like) and reinstall Ubuntu 16.04 on the other partition. How do I go about doing that?


Subsubgroups are subgroups of subgroups / Multiplicative Property of the Index

Algebra by Michael Artin Prop 2.8.14 Multiplicative Property of the Index  Statement of Prop 2.8.14     Let $G \supseteq H \supseteq K$ be subgroups of a group G. Then $[G:K] = [G:H][H:K]$.    Proof of Prop 2.8.14        Here's the original Counting Formula (Formula 2.8.8)        Question: Could we perhaps prove Prop 2.8.14 by using Counting Formula 2.8.8? I think we could do so () if we show that $K$ is a subgroup of $H$ which I guess hasn't been .


Using ArcMap 10.1, since there is not a way to control portrait or landscape of the layout view through python, is there a way to switch layout templates without opening a new mxd through python?   Since there is a change layout template button it would be nice to have a python function to do the same.


The item "Incense" has the description:     Incense with a mysterious fragrance that lures wild Pokémon to your location for 30 minutes.   Does this mean that if I stay still, over the next 30 mins Pokémon will come to me, rather than me walking around to find them?


If a function is measurable, then so is its absolute value.

How can I prove this proposition: If a function $f$ is measurable then, its absolute value, $|f|$, is also a measurable function?


For the purposes of the Banishment spell, are Undead considered native to the Shadowfell?

I can see reasons to argue either side, I'm wondering if there's an official source to settle the matter—how does the Banishment spell treat an undead?


Can not save changes to properties.settings

I'm trying to use properties.settings for the first time in a C# WPF project.  I have this code:    Settings.Default.comPort = ""; Settings.Default.baudRate = 9600; Settings.Default.startUp = false; Settings.Default.taskBar = true; Settings.Default.desktopNotif = false; Settings.Default.reset = false; Settings.Default.Save();     But it didn't work and the settings wasn't saved. So I added this line  Console.WriteLine("test");   after that part, to check if it goes through the code, and it executed fine. So It seems that it just jumps over those lines without execution or even throwing any exceptions.


Indenting subsections in table of contents

Above on the left is what my current table of contents looks like in a paper I'm writing and I really wish I could indent subsections like I showed on the right side (which I admittedly just did in Paint by moving them all over 16px, which seems like the ideal amount).  Would anyone know how I could incorporate this into my paper?  Here is the smallest MWE I could manage:  \documentclass[10pt,article]{amsart}  \begin{document}  \tableofcontents  \section{Section A} \subsection{Subsection (16px Indent)} \subsection{Subsection (16px Indent)} \section{Section B} \subsection{Subsection (16px Indent)} \subsection{Subsection (16px Indent)}  \end{document}


Objects that are Visualforce field component resolvable?

What does Visualforce field component resolvable mean?  I tried to bind columns editor to a list of custom Apex class instances, and naturally ran into this error. Rather than taking the workaround and breaking this up into inputXXX's I would prefer to modify the class to make it VF friendly. However, nobody seems to know what "Visualforce field component resolvable" means.  Do I need to decorate the class? Add specific metadata methods? Any ideas?  This is NOT a duplicate question.  My question relates to the second part of the description provided by the error message, stating that inputfield needs SOQL objects OR Objects that are Visualforce field component resolvable, which is not covered by the other answer.  Example:  public class Item {     public Boolean Selected { get; set; }  }  public List<Item> Items;   VF  <apex:pageBlockTable value="{!Items}" var="item" >     <apex:column headerValue="Select" >         <apex:inputField value="{!item.Selected}" />     </apex:column> </apex:pageBlockTable>   Save error:  Could not resolve the entity from  value binding '{!item.Selected}'.   can only be used with SObjects, or objects that are Visualforce field component resolvable.  To reiterate again, I know that inputField works with SOQL, what I want to know about is the meaning and implementation of the second part of the error message. How can one go about making a custom class VF inputField friendly.


We determine the area of the rectangle triangle (which is $\frac{rh}{2}$, $r$ is the radius of circle and $h$ the height). Then we can think that the volume of the cone is the area of the rectangle which runs the interval $[0,2\pi]$. Where is the mistake ? (Maybe it is the question of the "basis" considered)  Thanks in advance !


SharePoint 2013 - Sorry, apps are turned off. If you know who runs the server, tell them to enable apps

I am new to SharePoint 2013. I have developed an app using vs 2012. When I try to deploy the app, then I am getting the below error.  Error : Sorry, apps are turned off. If you know who runs the server, tell them to enable apps.   I have google it and find the below link:  http://technet.microsoft.com/en-in/library/fp161236.aspx   In this link, they are saying that Click Start, point to Administrative Tools, and then click DNS.  But I have not find DNS or DNS Manager.  Can any one help me.


Which is correct, "on-line" or "online"?

I am still seeing uses of on-line, though I think it is incorrect. For example:     A web browser enables a user to go on-line/online.   Can you tell me which is the more appropriate to use, on-line or online?


Calculating Dimension of Intersection of Kernels

Let T be sqaure matrix and regarded as a linear operator on a finite dimensional vector space V such that $T^2 = 0$.     $\dim(\ker T \cap \ker T^t) =\dim \ker T+\dim\ker\ T^t−\dim(\ker T\dot+\ker T^t) $    ($\dot+ $ denotes direct sum)  Is the abvoe equation true? If so, why is it so?


during installation of Ubuntu 14.04, I deleted all my data of my laptop including windows operating system! Is it possible to recover the deleted data and windows 10 operating system? If possible then how can i get them back?


How do get Ubuntu to stop modifying /etc/resolv.conf

I want to manually set my resolv.conf and have Ubuntu not automatically change it later.  How do I get Ubuntu to stop modifying resolv.conf?  I have already set "Automatic (DHCP) addresses only" in the network settings.


Initializing several empty lists with the list multiplication method links them together?

Apologies for the rather ambiguous title, but I couldn't think of a better way to put it. In Python, I can initialize empty lists or other variables like:  >>> a, b, c = [[]] * 3 >>> d, e, f = [0] * 3   I noticed that if I initialize the empty lists like this, then they are all connected so when I do:  >>> a.append(3)   The element 3 is also appended to lists b and c.  What is the reason for this behavior? Also, what is this style of initialization called? Thanks.


Off-topic questions from new, inexperienced users: How come?

EDIT: This question is as suspected a duplicate, so please check out the former post. Sonic's answer explains in detail how people end asking questions on Meta. Journeyman Geek . A better quantitative answer from Shog9 how people end here .  There are sometimes questions inside Meta where obvious new and inexperienced users are asking questions belonging to a site.  How do those users come to Meta? My experience is that you don't enter Meta accidentally. Do we have an non-obvious UI problem? If we track how they enter the site, is there an obvious route which can cause that an inexperienced user ends here?  Or do we have so many questions that those users are simply unpreventable outliers who do not care where they land and dump their question into Meta? :/


Any Info on Generalized Binomial and Exponential Series?

I was reading Concrete Mathematics by Knuth et al. and on p. 200, it references the generalized binomial series $\mathcal B_t(z)$ and the generalized exponential series $\mathcal E_t(z)$, defined as $$\mathcal B_t(z)=\sum_{k\ge0}(tk)^{\underline{k-1}}\frac{z^k}{k!}\quad\text{and}\quad\mathcal E_t(z)=\sum_{k\ge0}(tk+1)^{k-1}\frac{z^k}{k!},$$ where $x^{\underline k}$ denotes the falling factorial. I was interested in the generalized binomial series because it satisfied the identity $$\frac{\mathcal B_t(z)^r}{1-t+t\mathcal B_t(z)^{-1}}=\sum_{k\ge0}\binom{tk+r}{k}z^k.$$ I've been trying to find a way to compute the sum $\sum_{n\le k\le m}\binom{tk+r}{k}$, so this seemed related. It seems that $\mathcal E_1(z)$ is also somewhat related to the Lambert $W$ function, though I might be wrong. Searching them up online didn't seem to get anywhere, and I just want to find more sources where I can learn about these functions. If anyone can find some resources, I'd appreciate it!


A function of bounded variation is bounded

It seems that a function of bounded variation is bounded. But how do we prove it?  Maybe to show this, we should prove that if a function is not bounded, then it is not of bounded variation.  So let a function $f$ be unbounded. Now how can I show that $\sup$$t_f$ is not finite?  where $t_f$ =$\sum_{j=1}^n\lvert f(x_j)-f(x_{j-1})\rvert$ where {$a=x_0 \lt x_1 \lt...\lt x_n=b$} is any partition of [$a,b$].


ffmpeg split makes long file when not starting from beginning

Attempting to use ffmpeg to split a very long mp4.  ffmpeg -ss 00:00:00 -t 00:30:00 -i WorkingSession.mp4 -acodec copy -vcodec copy  WorkingSessionPart1.mp4   This provides about 89MB  Next I try this, notice the intentional time overlap  ffmpeg -ss 00:29:00 -t 00:30:00 -i WorkingSession.mp4 -acodec copy -vcodec copy  WorkingSessionPart2.mp4   This provides about 163MB even though it should just be the last minute of the previous half hour mp4  The clue I get is at the start, of the 2nd one I get:  [mp4 @ 0xf48fc0] Codec for stream 0 does not use global headers but container format requires global headers [mp4 @ 0xf48fc0] Codec for stream 1 does not use global headers but container format requires global headers   How do I bypass this, so as to split my mp4.  I have tried both -flags global_header, and -shortest:  ffmpeg -flags global_header -ss 00:29:00 -t 00:30:00 -i WorkingSession.mp4 -acodec copy -vcodec copy -shortest WorkingSessionPart2.mp4   but I still get the same error, and the much too long mp4 output file  Any suggestions?


Why isn’t the pronunciation of "though" anyhow close to the one of "tough"?

The word tough is pronounced /tʌf/. The word though has a completely different pronunciation, that is /ðəʊ/.    Is there a reason why the latter would not be pronounced /ðʌf/?


Does the universal quantifier express existence? If I say "All dogs are cute", does the truth of that proposition require at least one existent dog? My question is different from the suggested one as it is evolving in the comments section. Thanks.


One thing I find annoying when copying text from one document to the other is that it keeps the formatting of the original document. For example, if I need to copy an IBAN code into the e-mail, I will have to parse it through notepad and then to the body of the message.  Is there some way of making it a default setting that formatting is not copied?


I'm using the template provided by IEEE:  \begin{figure}[!t] \centering \includegraphics[width=0.8\columnwidth]{top} \caption{CAPTION} \label{fig-top} \end{figure}   However the caption is not centred. What I get is this:    Please help!


I found my own answer and I was very happy about it. I'm very sure I posted it. Maybe I deleted it myself because I got downvoted but I would still like to know who or why it got deleted. I remember clearly writing "HOLY SHIT[...]" in some variation because I got it working.


I'm a beginner photographer and I want to try take a picture of my friend dancing in the rain. I own a canon sx60 but unsure of what settings and accessories I need to pull it off.


Ubuntu 16.04 LTS won't search for or connect to wireless networks

I recently installed Ubuntu onto my external hard drive which is fine apart from the fact it will not allow me to search for or connect to wireless networks. My internal hard drive has Windows 7 installed and the wireless works perfectly fine and always has, so I doubt it's a hardware issue. However, the Ethernet is usable as I have a Huawei mobile wifi device and USB cable and can connect to the internet using that, but its not ideal and I wish to be able to connect to my home hub while I'm using Ubuntu. The name of my wired connection is "geometric".  I ran the wireless info script and the results are here:   I have tried sudo service network-manager restart but that didn't work. Another thread suggested adding the SUSPEND_MODULES line to the config file but that also didn't have any effect.


Best practice to gracefully fallback in perl module if log4perl not installed

Ok, so I'm trying to learn to properly use log4perl.  It seems like it would make sense that I could write a module that uses log4perl, but can also be distributed to a system where log4perl is not installed and still run without failing, just not log. If I have use Log::Log4Perl qw(:easy); in the module, compile fails with:  Can't locate Log/Log4Perl.pm in @INC ...   Basically, what is standard and best practice among users of log4perl to enable log4perl compatibility in a module without forcing it? It seems like something that should be common, but I can't find it to save my life.  Thanks in advance.  EDIT: Thanks for the feedback! I have edited the question to reflect that I am looking for the best practice among users of log4perl in this situation, given that certainly this must be a common issue among log4perl users... right?


We can say walking down this street, and we also say the shop is 500m up this building. Can we say walk up the street and in these cases, what direction is the up and down to, as in most cases, the road is flat without any slope. How we know which way is up or down?


Hide or Remove back button in Salesforce1 Urgent

How can i remove or hide back button in the salesforce one UI. it take back me to the previous page but i don't want to give this functionality. So how can i hide or remove back button from custom VF pages and Standard detail pages.


Problem: ( kriesi ) pagination doesn't work in homepage

When I set this template as homepage, pagination doesn't work. I see the buttons, but when I click the button for page 2, nothing happens, doesn't go on page 2, it still remain in page 1.  What is wrong? Where is the mistake? I read all posts from here & from internet about this issue, but nothing works.  Solution for pagination is this: .  Here is the code:

              <?php if (have_posts()) : while (have_posts()) : the_post();?>              <?php                $template_name =   get_post_meta( $wp_query->post->ID, '_wp_page_template', true );             $post_type =  str_replace( array('template-', '.php'), array(''), $template_name);             ?>              <?php the_content(); ?>              <?php endwhile; endif; ?>             <?php              $loop = new WP_Query("post_type=$post_type&paged=$paged");             if ($loop->have_posts()) : while ($loop->have_posts()) : $loop->the_post(); ?>               <?php get_template_part('loop', $post_type) ?>                                          <?php endwhile; ?>                                         <?php else: ?>                 <?php require THEME_DIR.'/empty.php'; ?>                                        <?php endif; ?>                                          <?php pagination($loop->max_num_pages); ?>
          <?php get_sidebar(); ?>


maximum daily reputation and top users score

If I get 30 upvote in answers with a particular tag, does it calculate 30 score for me in top users section  or just 20 score ? ( considering maximum daily reputation of 200 for upvotes )


Setting or modifying a (system wide) environment variable in cmd.exe

I am looking for a convenient way to add and/or modify and/or delete an environment variable from the command line. Particularly, I find myself at times in situations when I have to add a few variables in cmd.exe.  I'd be grateful if someone showed me a non-GUI way to modify (that is: to add a new directory to) the %PATH% variable.  The change should be be permanent, not just for duration of the cmd session.


I have seen numerous references on the internet of people describing SHA-256 as generating an "almost unique" hash.  . there are more.  Is there some mathematical basis to the almost uniqueness? I would have thought that as SHA-256 is an evenly-distibuted (?) hash algorithm which can accept any message (infinitely many) as an input and produces a fixed length (finite) hash - then there will in fact be an infinite number of each possible output - which I would think hardly qualifies as "almost unique".  Is there a basis for this statement?


Fibonacci-type Sequence with Complex Numbers

I have been playing around with Fibonacci-type of sequence that involve complex numbers.  I have stumbled upon the following sequence, which seemed interesting to me: $$0,1,2i,-3,-4i,5,6i,...$$ so $F_n = 2iF_{n-1} + F_{n-2}$.  These look like a sequence of natural numbers (except for $0$) where every other is multiplied by $i$ and the signs change after two sequences.    I understand the algebra behind the above sequence, but I have been wondering whether there is an intuition behind why the sequence looks like a "modified" sequence of natural numbers.


Why some superusers have Unicorn as profile pic?

Why some superusers(users with awesome reputation points) have Unicorn as profile pic?  I don't understand philosophy behind it.  You can check yourself ->                       Don't know how many more users are here with Unicorn.


Instead of having a global scope why the following code shows error?

I already declare b = 6 globally. But why this code shows an error instead of printing b = 6.But when I delete b = 33 inside that is inside the function the code works well & print b = 6. But why?  b = 6 def f(a):       print(a)       print(b)       b = 33  f(20)


I am missing libraries of certain ICs for use in Eagle. Can someone guide me to a source where I can find these IC libraries? I am asking this question to find out if there is any central repository where I can find most/all of the IC libraries.  Additional Information (if required):   Currently missing ICs are AD8318, ADL5542, and TLV3501 I am using Eagle v5.6.0 for Windows


In many grammar descriptions, it says that adjectives that end in -ed are used to describe a feeling (or how a person feels) or an emotion. It is used to describe a temporary thing. With an adjective like "rented", is this a different type of adjective? Or is this just an exception to the rule? Here are some of the grammar explanations that state this:


Which flavor of latex to use? LuaTeX, XeLaTeX or LaTeX?

When I started using TeX, it was easy to build. Today I discovered that I can use different flavor of LaTeX to build my (La)TeX files. Is there a general rule of which flavor I should consider for a regular project (let say a letter to the Tax Office)?  With inputenc and fontenc I was able to use unicode so why should I consider XeLaTeX or LuaTeX instead?


Are the original CM fonts better than the current type1 fonts?

What are the differences between the original (rasterized) CM fonts and the current (smooth PDF-friendly) type1 versions of these fonts?  It seems to me that the originals are much better looking. They are "thicker". You can clearly see the difference in printed output. The type1 ones are somewhat "thinner".  Why is this? Why aren't they exactly the same?  And final question: On a modern MacTeX distribution (on my Mac OS X), how can I compile my document with the older fonts?  Update: I feel the current answers haven't answered some of the sub-questions and, more importantly, haven't provided the proper understanding that I'm looking for. The question can be rephrased: I look at "Digital Typography" by Knuth and a recent mathematics book on my shelf. Both are clearly printed in very high resolution—the fonts are smooth and look how they are supposed to look. But the font in Knuth's book is far "thicker" and has a much warmer, juicier, and nicer feel to it. On the other hand, I recognize the font in the mathematics book as the modern ubiquitous "smooth type1" CM font. In comparison to the font in Knuth's book, it looks thin and pale. I'm looking for some foundational understanding for why this is the case and why it turned out this way. Any font experts in here?


Sata or CD drive port? Which one better for SSD boot drive

I've hp 15 au004tx laptop. Intel i7 6500u Nvidia 940MX 4GB 8 GB DDR4 RAM 1TB 5400rpm hard drive.    I want to upgrade my laptop with an SSD. I want to use SSD for OS installation and HDD for data storage. On which port should I connect the SSD, on default sata port(where HDD is connected) or on CD drive port?


Differentiate between bounty and accepted answers

I noticed that the color for a recieved bounty and an accepted answer are the same.    In the screen shot there is no difference for bounties and accepted answers. Can we have a little difference between the two. For example use the bounty indicator in rep changes for bounties.


How many megapixels is a 1000 pixel image?

I am asked to set some photos to 1000 pixel in order to make them smaller using the Irfan View program, but the program only accepts in megapixels. So, how many megapixels is 1000 pixel??


JavaScript equivalent of ?? operator in C#

Is there any equivalent of ?? operator as exists in C# in JavaScript to defeat 'undefined' checking?  For example:  var count = something ?? 0;


What does the number in brackets after a command in the manpages mean?

Often, I read something like command time(1) or printf(3) in the manpages.  What do the numbers in the brackets stand for?


I would like to use imputation for replacing missing values in my data set under certain constraints.   For example, I'd like the imputed variable x1 to be greater or equal to the sum of my two other variables, say x2 and x3. I also want x3 to be imputed by either 0 or >= 14 and I want x2 to be imputed by either 0 or >= 16.   I tried defining these constraints in SPSS for multiple imputation, but in SPSS I can only define maximum and minimum values. Is there any way to define further constraints in SPSS or do you know any R package which would let me define such constraints for imputation of missing values?  My data is as follows:     x1 =c(21, 50, 31, 15, 36, 82, 14, 14, 19, 18, 16, 36, 583, NA,NA,NA, 50, 52, 26, 24)    x2 = c(0, NA, 18,0, 19, 0, NA, 0, 0, 0, 0, 0, 0,NA,NA, NA, 22, NA, 0, 0)    x3 = c(0, 0, 0, 0, 0, 54, 0 ,0, 0, 0, 0, 0, 0, NA, NA, NA, NA, 0, 0, 0)    dat=data.frame(x1=x1, x2=x2, x3=x3)    > dat        x1 x2 x3    1   21  0  0    2   50 NA  0    3   31 18  0    4   15  0  0    5   36 19  0    6   82  0 54    7   14 NA  0    8   14  0  0    9   19  0  0    10  18  0  0    11  16  0  0    12  36  0  0    13 583  0  0    14  NA NA NA    15  NA NA NA    16  NA NA NA    17  50 22 NA    18  52 NA  0    19  26  0  0    20  24  0  0


Unable to hide the horizontal scroll tabs in a long code snipped

I faced the issue on several occasions, so I am reporting it here. Please see the screenshot for a better understanding of my concern.   I use a Mac. Please auto-hide it after, say, 1 second.  The last line always gets clipped when I scroll to the right.     {some long code - hello world - 123 456 sdf adsf adsf adsf adsf as fasf as fas fasd fasd fa sf adsf adsf adsf ads fads fads f dasf}


Teachers and students sometimes refer to homework assignments as "homeworks". Is that an acceptable usage?


The following code is supposed to sort the array initialized below.   int[] intArray = { 32, 42, 1, 23, 56, 75, 32, 23 }; int temp = 0;  for (int i = 0; i < intArray.length; i++) {   for (int j = 1; j < intArray.length; j++) {     if (intArray[j - 1] > intArray[j]) {       temp = intArray[j - 1];       intArray[j - 1] = intArray[j];       intArray[j] = temp;     }   } }   What should you type to get the sorted array and where should you type it?   I have tried some options such as System.out.println(temp) between the last two closing brackets and the one before those, but I am not getting all the values printed, and 32 is printing many times instead.  Writing the code System.out.println(j) or System.out.println(i) in the same area doesn't work either. Can you explain why these codes don't work?


Biggest powers NOT containing all digits.

Let $m>1$ be a natural number with $m \not\equiv 0 \pmod{10}$  Consider the powers $m^n$ , for which there is at least one digit not occurring in the decimal representation.  Is there a largest $n$ with the desired property for any $m$? If so, define $n(m)$ to be this number.  Examples :  $$m=2 \rightarrow 2^{168} = 374144419156711147060143317175368453031918731001856$$  does not contain the digit $2$.  All the powers above up to $2^{10000}$ conatin all the digits, so  $2^{168}$ seems to be the biggest power with the desired property.  $$m=3 \rightarrow 3^{106} = 375710212613636260325580163599137907799836383538729$$  does not contain the digit $4$.  All the powers above up to $3^{10000}$ contain all the digits, so $3^{106}$ seems to be the biggest power with the desired property.  So, probably $n(2)=168$ and $n(3)=106$ hold.  Is $n(m)$ defined for any $m$, and if yes, can reasonably sharp bounds be given?


How to remove bad smell from fridge and refrigerator?

How to remove bad smell of food from fridge and refrigerator?


My toshiba pen drive is now 4mb and i'm really freaking out. I have tried everything from easeus partition master, testdisk, hp usb disk utility. I've searched the entire web for help and nothing has worked. I even tried diskpart. When i go to the disk manager, there are no unallocated spaces. It's just the 4mb. I REALLY REALLY need help!!!


Is there a bijection between $(0,1)$ and $\mathbb{R}$ that preserves rationality?

While reading about cardinality, I've seen a few examples of bijections from the open unit interval $(0,1)$ to $\mathbb{R}$, one example being the function defined by $f(x)=\tan\pi(2x-1)/2$. Another geometric example is found by bending the unit interval into a semicircle with center $P$, and mapping a point to its projection from $P$ onto the real line.  My question is, is there a bijection between the open unit interval $(0,1)$ and $\mathbb{R}$ such that rationals are mapped to rationals and irrationals are mapped to irrationals?  I played around with mappings similar to $x\mapsto 1/x$, but found that this never really had the right range, and using google didn't yield any examples, at least none which I could find. Any examples would be most appreciated, thanks!


Error : MediaPlayer on a null object reference

I am coding in Android Studio (Mac), and I keep having the same mistake repeatedly. Attempt to invoke virtual method 'void android.media.MediaPlayer.setVolume(float, float)' on a null object reference This is where the error occurs : MediaPlayer mp = MediaPlayer.create(getApplicationContext(), R.raw.speechfall);             //mp.start();             mp.setVolume((float) 1.0, (float) 1.0);  Even when I'm adding "mp.start();" I get the same exception : Attempt to invoke virtual method 'void android.media.MediaPlayer.start()' on a null object reference I don't understand what I need to do because the same code (without the mp.start()) works properly on my teammate's computer (Windows). Is there a package that I need to download? or a plugin that I need to update? Thank you for your answers.


How to rename all the files in a directory to a particular format?

I have a directory in which I have lot of files in this format only. Below are just examples for two of my files.  file_948_of_2000_push_data_12345.log file_950_of_2000_push_data_12345.log   As you can see only difference is this file number 948 and 950. Now I want to rename all these files in this particular format as shown below:  files_948.log files_950.log   What is the best way I can do this?


How do I make a textbox that only accepts numbers by masking?

I have got a text box in WinForms which is just for entering phone numbers. how can I do it by just masking it. I have used if instruction but i want to use the mask. actually my biggest problem was that I didn't know even where is the mask text box.


Once I've signed in with a previous owner's Apple ID, then set up iCloud with my own Apple ID, is the activation lock transferred to me?

An iPad I have was previously set up with a different Apple ID (see  and ). I have since obtained the Apple ID and password for the previous owner, and used those to proceed through the welcome/setup process. It then asked for an another Apple ID for iCloud, and I gave it mine. Does that mean that it is now fully 'switched over' to my Apple ID, or might the activation lock still be associated with the previous owner, were the device ever to be reset? There doesn't appear to be anywhere in the settings screen explicitly associated with the activation lock, just the iCloud ID (which according to the setup process is a separate concept).


Splitting shapefile into separate shapefiles using ArcGIS Desktop

I have a multipart shapefile, which I would like to split into many individual shapefiles (by FID for example).   Is there some way to do this in ArcGIS 10.x without using python?


what Linux distro should i get for old laptop

its a windows xp for now so any how to tell how to do it in xp my old laptop:  Intel(R) Celeron(R) M processor 1.40 GHz and 224 MB of RAM


Command for taking a screenshot to a new file

I want to configure a global hotkey to take a new screenshot and save it, say, somewhere inside my home folder. I can take a screenshot with ImageMagick with this command:  import screenshot.jpg   However, if I execute this multiple times, screenshot.jpg will be overwritten multiple times. I want the application to write screenshot1.jpg, screenshot2.jpg, etc. automatically. What my command would look like in this case?


1.7.10 Crashing upon entering Multiplayer (no forge, normal mc)

when I try to join a Minecraft server running on 1.7.10, it just crashes when I join it. I'm trying to join invadedlands. The IP is right, but it crashes me after "Logging in..."  Crash log:  ---- Minecraft Crash Report ---- // My bad.  Time: 6/24/19 10:22 AM Description: Ticking screen  java.lang.IndexOutOfBoundsException     at java.nio.Buffer.checkIndex(Buffer.java:540)     at java.nio.DirectIntBufferU.get(DirectIntBufferU.java:253)     at bma.a(SourceFile:271)     at bma.a(SourceFile:220)     at bao.a(SourceFile:1694)     at bao.a(SourceFile:1652)     at bjb.a(SourceFile:125)     at hd.a(SourceFile:70)     at hd.a(SourceFile:13)     at ej.a(SourceFile:174)     at bcx.e(SourceFile:78)     at bao.p(SourceFile:1343)     at bao.ak(SourceFile:774)     at bao.f(SourceFile:728)     at net.minecraft.client.main.Main.main(SourceFile:148)   A detailed walkthrough of the error, its code path and all known details is as follows: ---------------------------------------------------------------------------------------  -- Head -- Stacktrace:     at java.nio.Buffer.checkIndex(Buffer.java:540)     at java.nio.DirectIntBufferU.get(DirectIntBufferU.java:253)     at bma.a(SourceFile:271)     at bma.a(SourceFile:220)     at bao.a(SourceFile:1694)     at bao.a(SourceFile:1652)     at bjb.a(SourceFile:125)     at hd.a(SourceFile:70)     at hd.a(SourceFile:13)     at ej.a(SourceFile:174)     at bcx.e(SourceFile:78)  -- Affected screen -- Details:     Screen name: bcx  -- Affected level -- Details:     Level name: MpServer     All players: 0 total; []     Chunk stats: MultiplayerChunkCache: 0, 0     Level seed: 0     Level generator: ID 00 - default, ver 1. Features enabled: false     Level generator options:      Level spawn location: World: (8,64,8), Chunk: (at 8,4,8 in 0,0; contains blocks 0,0,0 to 15,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)     Level time: 0 game time, 0 day time     Level dimension: 0     Level storage version: 0x00000 - Unknown?     Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)     Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false     Forced entities: 0 total; []     Retry entities: 0 total; []     Server brand: ~~ERROR~~ NullPointerException: null     Server type: Non-integrated multiplayer server Stacktrace:     at bjf.a(SourceFile:289)     at bao.b(SourceFile:1972)     at bao.f(SourceFile:737)     at net.minecraft.client.main.Main.main(SourceFile:148)  -- System Details -- Details:     Minecraft Version: 1.7.10     Operating System: Windows 10 (amd64) version 10.0     Java Version: 1.8.0_51, Oracle Corporation     Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation     Memory: 104190592 bytes (99 MB) / 167772160 bytes (160 MB) up to 2147483648 bytes (2048 MB)     JVM Flags: 8 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx2G -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M     AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used     IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0     Launched Version: 1.7.10     LWJGL: 2.9.1     OpenGL: GeForce GTX 1060/PCIe/SSE2 GL version 4.6.0 NVIDIA 388.16, NVIDIA Corporation     GL Caps: Using GL 1.3 multitexturing. Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported. Anisotropic filtering is supported and maximum anisotropy is 16. Shaders are available because OpenGL 2.1 is supported.      Is Modded: Probably not. Jar signature remains and client brand is untouched.     Type: Client (map_client.txt)     Resource Packs: [vanilla]     Current Language: English (US)     Profiler Position: N/A (disabled)     Vec3 Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used     Anisotropic Filtering: Off (1)


Is there difference between "go with" and "come with"?

There is no social shaming that comes with knowing nothing about our local politicals. (Joe Clein Column, Time Magazine, August26)  Can I change "come with" into "go with" here? It seems to me that "go with" is too much used as an idiom to mean something  essentially or normally goes together with something else. But here the author is just to negate any necessary relation between the two things.   Is the difference between "come with" and "go with" based on, or related to, the difference between "come" and "go"? Maybe the difference between them is just a product of habit?


Conformal transformation/ Weyl scaling are they two different things? Confused!

I see that the weyl transformation is $g_{ab} \to \Omega(x)g_{ab}$ under which Ricci scalar is not invariant. I am a bit puzzled when conformal transformation is defined as those coordinate transformations that effect the above metric transformation i.e $x \to x' \implies g_{\mu \nu}(x) \to g'_{\mu \nu}(x') = \Omega(x)g_{\mu \nu }(x)$. but any covariant action is clearly invariant under coordinate transformation? I see that what we mean by weyl transformation is just changing the metric by at a point by a scale factor $\Omega(x)$. So my question is why one needs to define these transformations via a coordinate transforms. Is it the case that these two transformations are different things. In flat space time I understand that conformal transformations contain lorentz transformations and lorentz invariant theory is not necessarily invariant under conformal transformations. But in a GR or in a covariant theory effecting weyl transformation via coordinate transformations is going to  leave it invariant. Unless we restrict it to just rescaling the metric?  I am really confused pls help.


Why 'xargs bash -c' is far slower than 'xargs sh -c'?

time seq 100 | xargs -i bash -c 'echo {}'   ; 2.530s  time seq 100 | xargs -i sh -c 'echo {}'   ; 0.223s  why?  PS: The title of mine for this post is more intuitive to be discovered or searched by google or any sort of search engines.


Number of distinct elements in $\mathbb{Z}[i]/\langle 3+i \rangle$

I have read numerous answers to similar questions, but I'm still stuck.  Here's my approach:  All elements in $\langle 3+i \rangle$ have the form $(a+bi)(3+i)=(a-b)+i(a+3b)= 2p + i 4q$, for $p, q\in \mathbb{Z}$, which implies that all other elements are not in $\langle 3+i \rangle$. But aren't there infinitely many such elements?  Can you please clarify what I'm not seeing in this problem?


Crontab not working for pageres, showing error MTA installed, discarding output

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We are creating a file deploy application for a team with SVN. Here is the new scenario that want us to do,  User creates folder1 and checks it in User creates folder2 and checks it in (rev2 now) User creates folder3 and checks it in (rev3 now)   At this point, the user thinks he needs to go back to revision 1. so we do  svn co -r 1    the user expects to see only folder1, but not folder2 and folder3. Is this doable? We are creating the script on the Linux command line so we won't have the luxury of SVN clients to use. Only the SVN commands.   Thanks for the help.


I just loaded the SE page, only to see it totally revamped.  How to see hot questions from all SE sites now?


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I am trying to add a number to an array .  code:  var year = mm[2].value+1;   but it results undefined.  can you guys how to do this?


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I found the relation below while studying the measure of dependence. How we can prove this relation about Kendall's tau? $$ \tau = 4\int\int H(x, y)\, h(x,y)\, dx\, dy - 1 $$


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I have a table with has many rows, I want to set unique constraint for this table, but the column that must be unique, has data is not unique. Is any way to set unique constraint for this table for this column or unique constraint for any insert or update next time?  I can't delete data because is real


I am trying to install Open MPI. I downloaded the archive and extracted the folder to /home/. I cded there and entered ./configure --prefix="/opt/openmpi" and got this error:  ./configure: line 4840: config.log: Permission denied ./configure: line 4850: config.log: Permission denied   I tried the following:   ls -l configure which gives -rwxrwxr-x 1 root root ... configure df -h .. I'm on /dev/sda6 grep '\s/home/\s.*noexec' /proc/mounts yields no results Prepend the command with sh   I try to avoid using sudo to install this. What can I do?


I am going to put an additional (non-USB) hard drive in my system. I already have Ubuntu on my other hard drive so I do not want to install Ubuntu on the additional drive but only use it for storage. How do I add the additional hard drive to my Ubuntu system, e.g. make Ubuntu recognize it and mount it properly?


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