First question, and an account made specifically for it. I'm having trouble getting citations to work from my bib file. I've spent the last several hours trying to get it to work, and as far as I can tell - I'm doing everything correctly! However, it is still not working. Even with the simplest files, I can't get teXnicCentre to read the citations inside my bib file, and cite them as expected. For a minimum working example, I have a tex file:  \documentclass[% oneside ,bibliography=totoc ]{scrbook}  \usepackage{amsmath}% \usepackage{amsfonts}% \usepackage{amssymb}% \usepackage[natbib=true]{biblatex}  \addbibresource{reflist.bib}  \begin{document} Creating a computerized model of the system then becomes part of the process to achieve deeper understanding of the phenomena, alongside observations and analytic theory \citep{Narita2004}. \printbibliography \end{document}   where the context in reflist.bib is a single citation:  @article{Narita2004, author = {Narita, Y. and Glassmeier, K.-H. and Sch{\"{a}}fer, S. and Motschmann, U. and Fr{\"{a}}nz, M. and Dandouras, I. and Forna{\c{c}}on, K.-H. and Georgescu, E. and Korth, a. and R{\`{e}}me, H. and Richter, I.}, doi = {10.5194/angeo-22-2315-2004}, issn = {1432-0576}, journal = {Annales Geophysicae}, keywords = {electromagnetics,inter-,physics,planetary bow shocks,planetary physics,space plasma,tions which are unstable,to different types of,wave propagation,waves and instabilities,waves at vari-}, pages = {2315--2323}, title = {{Alfv{\'{e}}n waves in the foreshock propagating upstream in the plasma rest frame: statistics from Cluster observations}}, volume = {22}, year = {2004} }   The .bib citation was generated by Mendeley (the database software I'm using), and although it looks messy it should still work as expected (to my knowledge). I'm trying to use the natbib commands in biblatex because I like the use of their /citep{} and /citet{} functions.  Any help? This has taken up far too much of my time already!  PS: When I run the files in TXC, all the aux, bbl, etc. files are generated. The .bbl file is blank (so no citations were sourced). In the .blg file, it states:  This is BibTeX, Version 0.99dThe top-level auxiliary file: example.aux I found no \citation commands---while reading file example.aux I found no \bibdata command---while reading file example.aux I found no \bibstyle command---while reading file example.aux (There were 3 error messages)   Yet, in the .aux file:  \relax  \providecommand*\new@tpo@label[2]{} \abx@aux@sortscheme{nty} \abx@aux@refcontext{nty/global/} \abx@aux@cite{Narita2004} \abx@aux@segm{0}{0}{Narita2004} \@writefile{toc}{\boolfalse {citerequest}\boolfalse {citetracker}\boolfalse {pagetracker}\boolfalse {backtracker}\relax } \@writefile{lof}{\boolfalse {citerequest}\boolfalse {citetracker}\boolfalse {pagetracker}\boolfalse {backtracker}\relax } \@writefile{lot}{\boolfalse {citerequest}\boolfalse {citetracker}\boolfalse {pagetracker}\boolfalse {backtracker}\relax }   I can see my citation key sitting in there, meaning that it actually has recognized that I've cited something... and for some reason it hasn't been picked up with it goes through the .bib file.   All files are in the same directory.

Running the minimal example  \documentclass{article} \usepackage{filecontents} \begin{filecontents*}{\jobname.bib} @ARTICLE{example,   author  = {Other, Anthony Norman},   title   = {Some things I did},   year    = {2014},   journal = {J.~Irrep. Res.},   volume  = {1},   number  = {1},   pages   = {1-10} } \end{filecontents*} \usepackage[backend=biber]{biblatex} \addbibresource{\jobname.bib} \begin{document} Hello\cite{example}. \printbibliography \end{document}   I get the warning There were undefined references.  I have read  and know that I need to run:   LaTeX Biber LaTeX   However, my editor is only set up to run BibTeX. How do I go about setting up my editor/IDE to be able to run Biber, and how do I run the LaTeX/Biber/LaTeX cycle?  Answers (sorted alphabetically by editor name)                    Answer guidelines   Each answer should be for one editor. If the editor is cross-platform, if possible give a single answer with notes covering the minor platform variations. Please edit the question to include new answers in the 'link list' Each answer should be 'stand alone', i.e. don't say 'It's almost the same as editor Y but ...' for the editor part Instructions for 'build tools' such as arara or latexmk are welcome but should explain how to set up the editor in question as not all editors allow simple addition of arbitrary tools


This is the package I am using to cite in my master thesis and the error that's occurring is the one displayed in the title. I don't understand where this error is coming from. If you need to see any more of the code for a solution just let me know. I'm happy for any help! Thanks a lot for trying to solve my problem.  \usepackage[backend=biber,style=numeric,natbib=true]{biblatex}  \addbibresource{Literaturliste.bib}  \ExecuteBibliographyOptions{sorting=nyt,maxbibnames=999,  maxcitenames=1,  backref=false,  bibencoding=utf8,  defernumbers=true}


I'm trying to migrate a MySQL-based app over to Microsoft SQL Server 2005 (not by choice, but that's life).  In the original app, we used almost entirely ANSI-SQL compliant statements, with one significant exception -- we used MySQL's group_concat function fairly frequently.  group_concat, by the way, does this: given a table of, say, employee names and projects...  SELECT empName, projID FROM project_members;   returns:  ANDY   |  A100 ANDY   |  B391 ANDY   |  X010 TOM    |  A100 TOM    |  A510   ... and here's what you get with group_concat:  SELECT      empName, group_concat(projID SEPARATOR ' / ')  FROM      project_members  GROUP BY      empName;   returns:  ANDY   |  A100 / B391 / X010 TOM    |  A100 / A510   So what I'd like to know is: Is it possible to write, say, a user-defined function in SQL Server which emulates the functionality of group_concat?   I have almost no experience using UDFs, stored procedures, or anything like that, just straight-up SQL, so please err on the side of too much explanation :)


I have a EC2 m1.large Ubuntu 13.04 Instance runs PHP 5.5, PHP-FPM and NGINX. Cache is handled by Elastic Cache using Redis and the database connects to a separate m1.large MongoDB server. The content can be fairly dynamic as newsfeed can be dynamic and my server is used by an iOS app.   I am doing siege tests siege -d5 -c150 if I do only 1 siege I see responses times that are less than 1 sec. If I add another server to do another siege -d5 -c150 my response times go up the roof to 9-15 sec`  I am very new to servers setups but somethings tells me that if my server is always average of 40-50% CPU load and consuming under 1GB of ram. I shouldn't see 10++ sec latency having so much free resources?   What could be my bottle neck or even better how could I find it??     /etc/sysctl.conf are   net.ipv4.tcp_fin_timeout = 30 net.ipv4.tcp_tw_recycle = 1 net.ipv4.tcp_tw_reuse = 0 net.ipv4.ip_local_port_range = 2000 65000 net.ipv4.tcp_no_metrics_save = 1 net.ipv4.tcp_window_scaling = 1 net.ipv4.tcp_max_syn_backlog = 3240000 net.core.somaxconn = 3240000 net.ipv4.tcp_max_tw_buckets = 1440000 kernel.shmmax = 1073741824 net.ipv4.tcp_rmem = 4096 25165824 25165824 net.core.rmem_max = 25165824 net.core.rmem_default = 25165824 net.ipv4.tcp_wmem = 4096 65536 25165824 net.core.wmem_max = 25165824 net.core.wmem_default = 65536 net.core.optmem_max = 25165824 net.ipv4.tcp_mem = 1474560    1966080    2949120   /etc/php5/fpm/pool.d/www.conf  pm = dynamic pm.max_children = 32 pm.start_servers = 3 pm.min_spare_servers = 2 pm.max_spare_servers = 5 pm.max_requests = 150   /etc/nginx/nginx.conf  user www-data; worker_processes 4; pid /run/nginx.pid;  events {     worker_connections 32768;     multi_accept on;     use epoll; }  http {      include       /etc/nginx/mime.types;     default_type application/octet-stream;      sendfile on;     tcp_nopush on;     tcp_nodelay on;     keepalive_timeout 15;      server_tokens off;      # allow the server to close the connection after a client stops responding. Frees up socket-associated memory.     reset_timedout_connection on;       # send the client a "request timed out" if the body is not loaded by this time. Default 60.     client_body_timeout 10;      # If the client stops reading data, free up the stale client connection after this much time. Default 60.     send_timeout 10;      ##     # Logging Settings     ##      access_log /var/log/nginx/access.log;     error_log /var/log/nginx/error.log;      ##     # Gzip Settings     ##      gzip on;     gzip_disable "MSIE [1-6]";      ##     # Virtual Host Configs     ##      include /etc/nginx/conf.d/*.conf;     include /etc/nginx/sites-enabled/*;     server {         listen 80 default;         root /var/www/;         index index.php index.htm index.html;          # php-fpm bridge         # execute all .php files with php-fpm            location ~ .php$ {               fastcgi_pass   unix:/var/run/php5-fpm.sock;               fastcgi_index  index.php;               fastcgi_param  SCRIPT_FILENAME $document_root$fastcgi_script_name;               fastcgi_buffer_size 128k;               fastcgi_buffers 256  16k;               fastcgi_busy_buffers_size 256k;               fastcgi_temp_file_write_size 256k;               include fastcgi_params;            }     } }   siege results  ransactions:                    1265 hits Availability:                  99.68 % Elapsed time:                1196.10 secs Data transferred:              21.30 MB Response time:                 11.48 secs Transaction rate:               1.06 trans/sec Throughput:                     0.02 MB/sec Concurrency:                   12.14 Successful transactions:        1265 Failed transactions:               4 Longest transaction:           26.88 Shortest transaction:           0.00

This is a  about  Related:      I have a question regarding capacity planning. Can the Server Fault community please help with the following:   What kind of server do I need to handle some number of users? How many users can a server with some specifications handle? Will some server configuration be fast enough for my use case? I'm building a social networking site: what kind of hardware do I need? How much bandwidth do I need for some project? How much bandwidth will some number of users use in some application?


I'm on OSX and if I run python --version in a bash shell, I get this:  $ python --version Python 3.7.3   But the which python command appears to be pointing to version 2.7.   $ which python /usr/local/bin/python ls -al /usr/local/bin/python lrwxr-xr-x  1 me  admin  36 11 Apr 22:28 /usr/local/bin/python -> ../Cellar/python@2/2.7.16/bin/python   I think this is because I have done alias python=python3: but why does which python not pick up the alias?

When looking for the path to an executable or checking what would happen if you enter a command name in a Unix shell, there's a plethora of different utilities (which, type, command, whence, where, whereis, whatis, hash, etc).  We often hear that which should be avoided. Why? What should we use instead?


I recall that the ratio of 2 independent standard normal random variables follows a Cauchy distribution, but I don't recall if there is a proof for this.

I am interested in      Let $X\sim N(0,1), Y \sim N(0,1)$ independently. Show $\frac{X}{X+Y}$   is a Cauchy random variable.   My work:  $f_{X,Y}(x,y)=\frac{1}{2\pi} e^{\frac{-1}{2}(x^2+y^2)}, -\infty<x,y<\infty$ by independence  Let $U=\frac{X}{X+Y},V=X+Y$. (Is there a better $V$ to choose for this bivariate transformation?)  Then, $X=UV, Y=V - UV$. So, $|J|=V$.  $f_{U,V}(u,v)=f_{X,Y}(uv,v-uv)|J|=\frac{v}{2\pi}e^{\frac{-v^2}{2}(2u^2-2u+1)},-\infty<u<\infty$  $f_U(u)=\frac{1}{2\pi}\int_{-\infty}^{\infty}ve^{\frac{-v^2}{2}(2u^2-2u+1)}dv$. Let $y=\frac{v^2}{2}(2u^2-2u+1)$, so $dy=v(1+2u^2-2u)dv$. Then,  $f_U(u)=\frac{1}{2\pi(2u^2-2u+1)}\int_0^{\infty}e^{-y}dy=(\pi[(\frac{u-1/2}{2})^2+1])^{-1}, -\infty<u<\infty$,   which is not exactly a Cauchy distribution. Where did I mess up? More importantly, how would you proceed in solving this problem?


I need to find car element in ArrayList. The ArrayList data like this { [1,mobile,5000]    [2,car,50000]    [3,bike,20000] }  and classes are  //pro.java import java.util.*;   public class Pro{  private int id; private String name; private int price;  public String toString(){   return id+" "+name+" "+price;   }  //getter & setter methods }   and the search code is like this  //Product.java System.out.println("enter name you want to search"); name = scanner.next(); Iterator it=al.iterator(); while(it.hasNext()){  if(it.next() == name){  System.out.println("Yes found");  }  else{  System.out.println("Not Found");  } }   it is the iterator reference object and al is the ArrayList reference object.  the search is always return Not found but the element what I find is exist. How to fix it in order to return FOUND? Please help me with the appropriate code Thank's.

I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?


Linked question ^^^ is WHEN. My question is HOW which is different. Also, the other question does not have an answer that addresses the question. The one answer it has, does not answer the question, so the statement below that the existing question is "Answered" is not true.    How can I determine when the bank has been paid on a deposited check. A typical bank statment about this is as follows:     Your bank also may not be able to determine that the check is   fraudulent when you deposit it. Rather, your bank may learn of the   problem only when the check is returned unpaid by the other bank,   which may take a couple weeks or more. Scammers try to make the item   look genuine, which will delay discovery of the fraud. Once the item   has been returned unpaid, your bank, generally, will be able to   reverse the deposit to your account and collect the amount of the   deposit from you.   What I want to know is how I can I find if the check HAS BEEN PAID BY THE OTHER BANK? Basically call up my bank and ask?  (I will consider answers unresponsive if they do not answer the question: for example, going on about fraudulent checks and how to detect them, why checks do not clear, how scams work, why a check might never clear, etc. I know these things.)

Someone has sent me a check for $250 in payment for property damage they caused in a car accident.  It would have been better if I had gotten a cashier's check or official check, but I'll have to make do with what I've got.  Since I've spoken directly with the person, and since I have their address and phone number, I'm fairly sure this is a good check.  But I really can't be 100% sure.  So once I deposit it, when can I consider the check to be "cleared"?  That is, at what point can I be sure that the $250 is irrevocably mine?  There are other questions that have dealt with something similar (like the advance-fee fraud that probably underpins ) but since the focus of the question was different, there wasn't a clear answer on the time for clearing a check.  Thanks to anyone who knows.


I have installed python 3.6 in an Ubuntu 16.04 platform that had previously python 3.5  now if I check the installed version I have:  ls -l /usr/bin/python* lrwxrwxrwx 1 root root       9 Nov 24  2017 /usr/bin/python -> python2.7 lrwxrwxrwx 1 root root       9 Nov 24  2017 /usr/bin/python2 -> python2.7 -rwxr-xr-x 1 root root 3492656 Nov 12 19:46 /usr/bin/python2.7 lrwxrwxrwx 1 root root      33 Nov 12 19:46 /usr/bin/python2.7-config -> x86_64-linux-gnu-python2.7-config lrwxrwxrwx 1 root root      16 Nov 24  2017 /usr/bin/python2-config -> python2.7-config lrwxrwxrwx 1 root root       9 Mar 23  2016 /usr/bin/python3 -> python3.5 -rwxr-xr-x 2 root root 4464368 Nov 12 16:27 /usr/bin/python3.5 -rwxr-xr-x 2 root root 4464368 Nov 12 16:27 /usr/bin/python3.5m -rwxr-xr-x 2 root root 4719712 Dec 25 04:54 /usr/bin/python3.6 -rwxr-xr-x 2 root root 4719712 Dec 25 04:54 /usr/bin/python3.6m lrwxrwxrwx 1 root root      10 Mar 23  2016 /usr/bin/python3m -> python3.5m lrwxrwxrwx 1 root root      16 Nov 24  2017 /usr/bin/python-config -> python2.7-config   However if I check the version that is running is:  python3 --version Python 3.5.2   The same in the jupyter notebook    How can I set Python 3.6.7 as default instead of Python 3.5.2?

The python program command executes Python 2. Python 3 can be executed using the python3 command.  How can Python 3 be executed using the python command?


When I do a branded search for a website the structure shows like ( see image ). I would love to remove Privacy Policy page or Manipulate the structure I see now ( showing pages I want to ). How I can do it?     I already added robots - nosnippet meta tag to remove all rich snippets from a page, but it didn't work. Are there any other methods except removing page from indexation?

How can I remove Search for product, About us, Log in, etc. which are displayed in Google Search?  And how can I add particular categories like Automobiles, Mobiles & Tablets, etc.?


I need to prove that if $\alpha: I\rightarrow \mathbb{R}^{2}$ is regular with curvature $\kappa$, then $\alpha$ is on a circle with radius $r>0$ if and only if $|\kappa(t)|=\dfrac{1}{r}$.

I'm trying to prove that if $\alpha(t)=(x(t),y(t))$ is a $C^2$ regular curve $(\alpha'\neq0)$ with constant and positive curvature, then $\alpha$ is on the circunference and if $\alpha$ is the circunference, then its curvature is constant.  I solved the second part since $\alpha$ is the circunference, then $\alpha(t)=(r\cos\theta,r\sin\theta)$, so $|\alpha'(t)|=r$, I need help in the first part.  Thanks a lot.


We're trying to make an animation pretty much like toilet roll being wound onto a cylinder (but the cylinder is invisible)  We've managed to do this:    by moving the planes along a spiral but really that means the coil is too wide at the beginning but the end result is good.  Is there another way to achieve this goal because I think what we are doing now is fundamentally flawed in its approach?  This is not the same as  - this approach also rolls a plane onto a spiral. I'm trying to get the effect that a material rolls onto a cylinder like a cassette tape winding onto a reel. This is almost backwards from the spiral approach because the first fold should be the smallest ....

I want to animate a paper as it's being tightly rolled. I've done some research and seen that using the spiral add on might be advantageous, but I haven't found anything relating specifically to my question.   How might I do this?


I am using jupyter ide and I am getting different results for print(word) and appending to lst.  word = ["M","A","R","I","N","E"] goal = ["A","I","R","M","E","N"] lst = []  def search(ind_a,a,b,word):     for x in range(len(word)):         if word[x] == b:             temp=b             word[x]=word[ind_a]             word[ind_a]=temp             return word  def sequence(word,goal):     for ind_x,x,y in zip(range(len(word)),word,goal):         if(x==y):             continue         word=search(ind_x,x,y,word)         print(word)         lst.append(word)     return lst   when I called sequence(word,goal),I get succeding out:  sequence(word,goal)   Output:   ['A', 'M', 'R', 'I', 'N', 'E']#print word statement ['A', 'I', 'R', 'M', 'N', 'E'] ['A', 'I', 'R', 'M', 'E', 'N'] Out[193]: [['A', 'I', 'R', 'M', 'E', 'N'],#return statement  ['A', 'I', 'R', 'M', 'E', 'N'],  ['A', 'I', 'R', 'M', 'E', 'N']]   where am ı wrong?

I needed to create a list of lists in Python, so I typed the following: my_list = [[1] * 4] * 3  The list looked like this: [[1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1]]    Then I changed one of the innermost values: my_list[0][0] = 5  Now my list looks like this: [[5, 1, 1, 1], [5, 1, 1, 1], [5, 1, 1, 1]]    which is not what I wanted or expected. Can someone please explain what's going on, and how to get around it?


I play clash of clan on my mom s account now I have my own account so I want to transfer the game data from my moms account to my account I am using android so google+ please help.

I want to give my account to someone but I want to keep my G+ account. I hold this G+ account very dear to me and I can't give it up.  I've watched some clips about transferring accounts to another device. But I haven't found a video on how to transfer Clash of Clans account from one G+ to another G+ account.  I am using android OS.  EDIT:  I managed to transfer account but if someone else has your Gmail and pass then they can take it.


For some reason, I had to add an alias to my bash. I have added the alias in /root/.bashrc which also contains the following piece of code:  # Source global definitions if [ -f /etc/bashrc ]; then         . /etc/bashrc fi   The new alias works like a charm when it is used in the console. However, when I execute a script file myscript.sh with this alias in, I get a command not found error. It seems like I should tell .sh files to use the same environment as bash but I don't know how to do that.

In my ~/.bashrc file reside two definitions:   commandA, which is an alias to a longer path commandB, which is an alias to a Bash script   I want to process the same file with these two commands, so I wrote the following Bash script:    #!/bin/bash  for file in "$@"     do     commandA $file     commandB $file done   Even after logging out of my session and logging back in, Bash prompts me with command not found errors for both commands when I run this script.  What am I doing wrong?


I have seen in C++ program, during function declaration if there is no parameter for the function void is declared as parameter like this:  int F1(void)   How is it different than:   int F1()

I'm currently refactoring/tidying up some old C code used in a C++ project, and regularly see functions such as:  int f(void)   which I would tend to write as:  int f()   Is there any reason not to replace (void) with () throughout the codebase in order to improve consistency, or is there a subtle difference between the two that I am unaware of?  More specifically, if a virtual member function in C++ is described as:  virtual int f(void)   and a derived class includes a member function:  int f()   is this a valid override?  Additionally, am I likely to encounter any linker problems based on almost identical signatures?


Over the course of the last 30 month, I GMed ongoing campaigns for three different groups. One of them had to be disbanded due to one problematic player. Another one dissolved because we couldn’t find enough time to play together. But I really liked some of the players (and their characters) in these two groups. So I integrated them all in the third campaign, which is still going strong. Everybody loved it. Some former PCs were now downgraded to NPCs, but my players like to take turns and play them during combat encounter. This big pool of characters (inlcuding support characters) could split up and tackle different obstacles within the campaign. It’s like Avengers: Infinity War, when everybody is in the same movie and cool stuff is happening all over the place.  Now, the end is near. The last session lies ahead. And my problem is, that there will be way too many characters running around in the last battle. I asked my players how they picture this confrontation in their heads and they answered: “We want an epic battle with ALL of our allies against the BBEG and his underlings”. I’m not a huge fan of encounters with too many combatants, but if my players want that, why not. But I have no idea how to pull that off.  Just to give you an overview. There are a Lvl9 Sorcerer/Warlock, Lvl9 Fighter/Wizard, Lvl8 Rogue, Lvl6 Druid, Lvl6 Artificer, Lvl6 Barbarian/Bard, Lvl6 Bard/Rogue, two Lvl6 Wizards, Lvl6 Paladin, Lvl6 Fighter, Lvl5 Wizard, Lvl6 Cleric, Lvl5 Fighter/Rogue/Bloodhunter, Lvl4 Fighter/Barbarian, Lvl4 Druid, Lvl4 Cleric/Artificer, a CR 3 construct, a ghost and a sentient familiar with kickass magic items.  That’s 20 characters.  In the last couple of sessions, I really challenged them with some encounters that had a CR way too high for their level. But they (ab)used some synergies between their characters and managed to win anyway. It was awesome. Now I’m afraid that the final encounter against the BBEG will either end as a picnic in the park, or with a TPK in round 2.  At first, I thought about pitting them against 20 enemies. This way I could make them roughly equal in power level to the party. But this doesn’t work for two reasons. For one thing, there is no reason why the BBEG would suddenly have so many previously unknown henchmen. He has some of his high-ranking generals by his side, all of which are known (and hated) by the player characters. I cannot justify ten new guys, because my players would ask “Who are they? And why do they show up in the last session and were never seen before?”. Secondly, if there are 40 individuals in initiative order, it will take an hour for 1 turn.  So I figured, if I drastically reduce the number of enemies, the encounter will be much more manageable. I just have to make the enemies more powerful. But as I’ve already learned, action economy is something to pay attention to in 5e. If my players focus on one enemy with their attacks/spells/abilities, that enemy is probably dead before his/her second action. No problem … I just make my enemies REALLY powerful. But that would also suck, because really powerful enemies would oneshot the player characters.  So my problem boils down to this: if I make a single enemy powerful enough to survive focus fire from 20 player characters for 1 turn, this enemy would also be powerful enough to kill one of the player characters in 1 turn. On the other hand, I could just quadruple the HP of the enemies and leave the other stats untouched. But then my players would ask why some of these enemies have 400+ HP for no apparent reason. So ...  How can I design a balanced combat encounter for 20 characters? If that’s impossible, what other options do I have to handle this problem?

For instance, a party of four player characters raise a force of 30 militia men to go take a bandit camp. When they get there the bandit camp has 40 men, and none of them notable.  For the sake of simplicity, both the 30 men and the 40 bandits are armed with long swords, and wearing leather armor.   Is there a proper way to handle combat between the 30 man militia and the 40 bandits while also incorporating our four player characters? If no "proper" way exists, is there a generally accepted "best" way?


Can you call class methods from inside a view page?    Specifically ones that are not passed into the view?  In asp.net MVC I can do this:  <%= SomeClass.FixDateFormat(ViewData.Model.SomeClass.DateCreated) %>

Is it possible to access a constant value (i.e. a public static final variable defined in a Java class) from a Velocity template?  I would like to be able to write something like this:  #if ($a lt Long.MAX_VALUE)   but this is apparently not the right syntax.


In bash, I have defined   chg_Li=3 chg_Na=9   Now I want to call $chg_$i where i is in a for loop, looping over Li and Na.  What is the correct syntax to call $chg_$i?

I am trying to print a simple value for $AR1_p1 but the variable $i is not evaluating. for i in 1 2 3 4 do     AR1_p1=22     AR1_p2=23     AR1_p3=24     AR1_p3=25     echo $AR1_p$i done   It's like concatenating dynamically. Any suggestions on how to fix this?.


My try :   I can proceed from here but as you all know that it will take more than 1 page , but I want a short approach for it.

If $$\frac{\tan (\alpha + \beta - \gamma )}{\tan (\alpha - \beta + \gamma )}=\frac{\tan \gamma}{\tan \beta}$$ then prove  $$\sin (\beta - \gamma)=0$$ or $$\sin 2\alpha + \sin2\beta + \sin 2\gamma =0$$ here my try goes -  To prove $\sin (\beta - \gamma)=0$, sin x = 0, only when x = 0 or 360 degree, but for the sake of simplicity let's take x = 0, then we've to prove that $\beta - \gamma =0$ or $\beta = \gamma$.  Now,   If $\beta = \alpha$, then first equation will be $\frac{\tan \alpha}{\tan \alpha}= \frac{\tan\gamma}{\tan\beta}$  or $\frac{\tan\gamma}{\tan\beta}=1$  and   $$\frac{\tan x}{\tan y}=1$$, only if $$\tan x = \tan y$$  So, also in this case $\tan \gamma$ must be equal to $\tan \beta$ so, as to prove that $\sin (\beta - \gamma)=0$.  So, how to prove that $\beta = \gamma$?  and how to solve the second part of the question here?


So just as the question states, I'm wondering how python calculates equations such as   def indeterminate(x):     return (x - math.sin(x)) / math.pow(x, 3)   where Limit approaches 0. I'm asking because when I input   >>> indeterminate(0.0000001) 0.17205356741102978   Where as   >>> indeterminate(0.00000001) 0.0   Shouldn't the output be approaching 1/6? And if it becomes too close, wouldn't a ZeroDivisionError message be more suitable than 0.0?  Another question I have is how do I calculate the actual number of   indeterminate(0.00000001)   The correct answer using L'hopital's rule should be 1/6 but (0.166666...) and not 0.1720...

Consider the following code:   0.1 + 0.2 == 0.3  ->  false   0.1 + 0.2         ->  0.30000000000000004   Why do these inaccuracies happen?


This was inspired by a recent question about the .  As far as I can recall, during Harry's time at Hogwarts, there were no places within Hogwarts castle or the school grounds where the students would have to regularly spend money (at least during term time). I know that people can easily forget they have money in their pockets, but students at Hogwarts appeared to have no reason to always keep money on-hand. The only exceptions I can recall to this were mail-order items - like when Harry and co. order presents for each other - or paying the owls for newspaper and magazine subscriptions.  My question is, aside from what I've mentioned above, were there any approved shops, services etc. within Hogwarts that the students had to pay money for? Let's assume the early days of Weasleys' Wizard Wheezes doesn't count as they probably weren't operating within the school rules!

I have been re-reading the Harry Potter books again and I noticed that Harry, Ron and Hermione have been giving each other Christmas presents each year at Hogwarts. How have they been able to buy each other presents if they are not allowed to go out of Hogwarts?   From their third year on they could visit the village and buy presents there, but what about the first two years? Did they give their personal belongings? Or did they just happen to have boxes of chocolates or books to give each other?


While watching the Star Wars Holiday Special a segment near the middle includes a cartoon where C3PO talks about a virus that only effects humans (referring to Luke who had previously passed out). Is the Holiday Special considered canon?

Is there a canon mention that Kenobi, Windu, Palpatine, the Skywalkers etc. are the same human species as all the other humans in  like Han Solo?  They look like humans, but we know that they're different in at least one characteristic: midi-chlorian hosting, which I suppose humans can't do as per definition.    Answers only from Canon, please. EU is welcome...


My question is the same as in the link provided below but when I go to Google Search Console it asks me to verify my Github profile https://github.com/[xyz] by inserting an HTML file. I am unsure about how to do that or are there any other ways that I can verify my GitHub profile.  Similar question:   Google serch console:

Is there any way to index my Github account to google search. I see that many people's account show up as soon as I type their name, but mine doesn't show up even after I type my name followed by github n search.


11 people in a certain company have access to a safe. The company owner wants any group of six people out of the 11 to open the safe, But no five-person group can open the safe itself. To achieve this goal he decided to put more than one lock on The safe, and give each person keys only to some of the locks. How many locks he has to put on the safe and how many keys each person will have to achieve his goal (the company owner wants to reduce the number as much as possible The locks, and as much as possible reduce the number of keys each person receives)?  Any ideas how to approach this question?

There are 8 crew members, The leading member wants that only a crew of 5 people or more could open a safe he bought, To each member he gave equal amount of keys, and locked the safe with several locks.  What's the minimal number of locks he should put:   at least 5 crew members would be required to open the safe? Any team of 5 crew members could open the safe, but none of the 4 team crew members.   1,2 stands individually of course.


This question has generated a lot of downvoting on three SE sites so let me try to explain where it comes from.  The magnitude of the bash "shellshock" problem may turn out to be larger than anything since Y2K.  Having been part of a complete replacement of a large data center for Y2K, I'm alarmed at the panic that's been generated over shellshock (appropo name, btw). I'm concerned that rushing in quick fixes without extensive planning and testing is going to create far greater problems than the one we think we are facing.  For Y2K, we learned that the date code fixes were the easy part.  The massively more complex, error-prone, and unscheduled downtime-producing part was discovering and fixing/mitigating the failures in other software caused by the fixes. Some of these weren't discovered until the new systems had been in production for months. Despite a herculean effort, a few even resulted in organizational policy changes because they were too disruptive to fix.  I am not suggesting that security-patching is unadvisable.  However, in this case only, I have noticed a suspicious series of events culminating in not just another run-of-the-mill vulnerability, but one demanding massive updating of systems affecting virtually every person using a computer on the planet.  The vulnerability is real. But is the need for instant action?  It is this combination of factors that gives me pause...  A fact...      A timeline...         Ramifications...   The Bash shellshock "vulnerability" has been a "feature" of Bash for 22 years. You'd think in all that time, in all those high-security environments that run Unix or Linux, someone would have worried about misuse. Now, every installation of Bash in the world is about to be replaced. Though Bash is open-source, few people actually take the time to study the code of such large and complex programs. Bash is written in C, which supports embedded assembly-language code. Code that even fewer programmers have the skills to read. Bash is written in C, which easily supports treating any block of binary, such as something labeled as data or a small image, as code. Thus, a skilled programmer could hide "backdoor" code in plain sight, and it probably wouldn't be discovered unless it caused an error of some kind.   The claim...  ""  The question...  Should bash shells be replaced with these new patched versions?  RESOURCES          Update 2017-09-28  After 3 years, someone actually found a sliver of usefulness in this and upvoted the question?  Well then, let me a mea culpa...  The above's focus on the circumstances surrounding Shellshock's announcement were a knee-jerk reaction on my part. A reaction I regret. While factual, the "conspiratorial" tone produced a backlash that obscured anything of value. I leave it intact only so that the many good comments make sense.  Enough new versions of most of the software involved have been released and well vetted by now that Shellshock may only still be of some concern to those running low-powered systems that must use older software. My alarm at the time was over the dangers of blindly removing 22 year old functionality from those systems with no analysis of the impact. Apparently, it turns out that the functionality was rarely, if ever, used.

Red Hat recently  in the Bash shell. Some are calling it the "shellshock" bug. Since OS X is built off of Unix, is it vulnerable to attacks that exploit this bug?   As an end user, do I need to worry about an immediate fix? Or is it better for me to wait for an official software update from Apple?


I have a function that has 5 requqired parameters and 2 optional ones. So a user can input 5-7 parameters and they are stored inside of an array. How can I pass those values to the function, is there something similar like extract() that returns the values and not the numbers? E.g.: $arr = ['one', 'two', 'three', 'four', 'five', 'six']; functionname($arr[0], $arr[1], $arr[2],$arr[3],$arr[4],$arr[5])  doesn't work, because I never know for sure if the sixth parameter really exists. Thanks for any help.

Python provides the "*" operator for unpacking a list of tuples and giving them to a function as arguments, like so:  args = [3, 6] range(*args)            # call with arguments unpacked from a list   This is equivalent to:  range(3, 6)   Does anyone know if there is a way to achieve this in PHP? Some googling for variations of "PHP Unpack" hasn't immediately turned up anything.. perhaps it's called something different in PHP?


Let $f:[0,\infty)\to \mathbb R$  be Continuous and strictly decreasing function such that : $\lim_{x\to \infty}f(x)=0$ prove  $$\int_0^\infty \frac{f(x)-f(x+1)}{f(x)}$$ Diverges.  I can not prove. please help .

Let $f:[0,\infty)\rightarrow \mathbb{R}$ be a continuous and strictly decreasing function. If $\displaystyle\lim_{x\rightarrow\infty}f(x)=0$, prove that the following integral is divergent :   $$\int_0^\infty \frac{f(x)-f(x+1)}{f(x)}dx$$   First, it's not hard to see that $f(0)>0$ and also $f(x)>0$ for each $x$.  I think we have to show that behavior of $\frac{f(x)-f(x+1)}{f(x)}$ is "similar" to $\frac1{x+1}$  or $\frac{f(x+1)}{f(x)}$ is "similar" to $\frac{x}{x+1}$ for big values of $x$.  But meaning of "similar" is not clear yet !  The most naive and rough approach is to show $\frac{f(x+1)}{f(x)}<1-k$ for some $0<k<1$ and therefore $f(x)-f(x+1)>kf(x)$.  One step forward, it's good to compare $\frac{f(x+1)}{f(x)}$ and a multiple of $\frac{x}{x+1}$ or equivalently to compare $C (x+1)f(x+1)$ and $xf(x)$. But still I can't extend this idea .  I tried more ways but I couldn't find a proper way to solve the problem.  Any hint is appreciated !


I'm trying to follow the solution in  to disable extra touchpad device so that  syndaemon will work to disable the touchpad while typing so I won't keep having a jumping cursor (very hard to type right now)!  Having trouble following the instructions, not familiar with Ubuntu that much. I enter the following:   sudo gedit /usr/share/X11/xorg.conf.d/51-synaptics-quirks.conf   That opens the text file.  I then paste the following:  # Disable generic Synaptics device, as we're using # "DLL0704:01 06CB:76AE Touchpad" # Having multiple touchpad devices running confuses syndaemon Section "InputClass"     Identifier "SynPS/2 Synaptics TouchPad"     MatchProduct "SynPS/2 Synaptics TouchPad"     MatchIsTouchpad "on"     MatchOS "Linux"     MatchDevicePath "/dev/input/event*"     Option "Ignore" "on" EndSection   Then click save and get the following errors:  ** (gedit:6473): WARNING **: Set document metadata failed: Setting attribute metadata::gedit-spell-language not supported  ** (gedit:6473): WARNING **: Set document metadata failed: Setting attribute metadata::gedit-encoding not supported  ** (gedit:6473): WARNING **: Set document metadata failed: Setting attribute metadata::gedit-position not supported   So not able to fully complete this solution.  Let me know if you can help so I can perhaps make this new Dell Inspiron 15 7579 usable (trying both 17.04 on thumb drive and 16.04 LTS on external hard drive).

I have upgraded 14.04 to 16.04 . Now I am trying to open the gedit from terminal by passing the command:    sudo gedit /some/where/file.txt   but it is throwing an error stating that:    (gedit:2090): Gtk-WARNING : Calling Inhibit failed: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown:   The name org.gnome.SessionManager was not provided by any .service files**   However, it is opening the file. When I try to save any modification then it is showing this error after saving the file:    (gedit:2090): WARNING : Set document metadata failed: Setting attribute metadata::gedit-position not supported   I am not getting why this is happening in 16.04 only; it was not on 14.04.


I have a folder /mqlocal/mqm. inside that there are 2 text files  (bindu.txt,sujitha.txt). I need code to count the number of text files under the directory. The result should be an integer.

For the purpose of testing, I'd like count how many images files are inside a directory, separating each image file type by file extension (jpg="yes". This because later it will be useful for another script that will execute an action on each file extension). Can I use something like the following for only JPEG files?  jpg="" count=`ls -1 *.jpg 2>/dev/null | wc -l` if [ $count != 0 ] then echo jpg files found: $count ; jpg="yes" fi   Considering file extensions jpg, png, bmp, raw and others, should I use a while cycle to do this?


Hi i have a problem with Microsoft Edge and lightning Component, the thing here is that i build a lightning component and works fine on all other browsers but when i test it on Microsoft Edge it shows me this error:  This page has an error. You might just need to refresh it. Error in $A.getCallback()[Unabled to get property 'apply' of undefined or null reference] Failing descriptor: {markup://aura.html}   I searched about that error on salesforce forums and no one has the solution, then i found that that error is due to a javascript syntax error. I changed the syntax of the tag that has the 'onclick event' from:  <button onclick="{! c.someAction }">Action</button>   to:  <button onClick="{! c.someAction }">Action</button>   You can see that only changed the 'c' to upper case and the error is not showing anymore, but anyways it doesnt do anything.  PD. On my controller code i only have a console.log.

We have a community built with custom lightning components and the locker service update is active. The onclick event has been defined on several components. The onclicks are working fine in Chrome, Firefox and IE11.   Save   There seem to be some issues in MS Edge though. When we click on an element with an onclick defined, we get the following error:     This page has an error. You might just need to refresh it. Error in $A.getCallback() [Unable to get property 'apply' of undefined or null reference] Failing descriptor: {markup://aura:html}    We have been testing on 5 different laptops. 3 of them have the error, while the other 2 don't have the issue in Edge. This was all tested in a Spring 17 sandbox. We also tested on a Winter 17 org with one of the laptops that has the issue and then everything seems to work fine.  Another test we did, was to remove all of the logic within the controller method and just have a console.log in it, but it never reached that point of the code since we didn't get the log. We also replaced the expression for the onclick with an alert, but that also doesn't work.  Does anyone have an idea how we can resolve this?


Since spectrum of noetherian ring is a noetherian topological space, I am finding an example s.t. a non-noetherian ring whose spectrum is noetherian.  Since most nice rings are noetherian, actually I do not have many examples to start, does any one can help? Thanks!

Question 1: Does such a ring exist? Note: The definition of a noetherian topological space is similar to that in rings or sets. Every descending chain of closed subsets stops after a finite number of steps (Question 2: is this equivalent to saying that every descending chain of opens stops?)


I submitted my manuscript to a journal from 1 month ago in scholar one. The status changed to admin check to under review after one week. Now, it shows Awaiting Decision.    Does this mean that the paper has passed the editorial check and the external reviewer completed?

What steps does a manuscript typically go through from submission to publication (or rejection) in a typical journal? How are these steps referred to, in particular by editorial systems, and how long do they each typically take?  Note that this question is about the typical situation and hence not about:   Journals with an atypical workflow, e.g. those that allow for an instantaneous reviewer–author interaction. Exceptional steps or rare occurrences such as withdrawal or .   This is a canonical question on this topic as per . Due to its nature, it is rather broad and not exemplary for a regular question on this site. Please feel free to improve this question.


When I ask question about java code ,  I copy the code in eclipse. And then I paste the code on the web board like here.  But the code's color become black only. Red, blue colors are not showing.  How do I preserve the code's color when I write down the code on web?

I noticed that sometimes my code gets highlighted in different colors when rendered.   What is syntax highlighting? How does it work? Why isn't my code being highlighted correctly? How do I report a bug or request a new language? How do I use syntax highlighting? What languages are currently available on Stack Exchange?


This is what i know about symmetric distributions: The distribution of rv (random variable) $X$ is symmetric about $a$ iff $$  P ( X \le a - x ) = P ( X \ge a + x )  \qquad \forall x  \in \mathbb{R} $$ I just want to confirm ,.,is this " iff " correct ? i mean it is clear to me that if $x$ is symmetric about $a$ it will satisfy above equation, is the converse also true ?

What's the definition of a symmetric distribution? Someone told me that a random variable $X$ came from a symmetric distribution if and only if $X$ and $-X$ has the same distribution. But I think this definition is partly true. Because I can present a counterexample $X\sim N(\mu,\sigma^{2})$ and $\mu\neq0$.  Obviously, it has a symmetric distribution, but $X$ and $-X$ have different distribution! Am I right? Do you guys ever think about this question? What's the exact definition of symmetric distribution?


i have this if else statement that always return ( other than 0 ) 'hey', but when the condition == 0, it will not display the 'ho' value. Appreciate advice. Thanks. $('#icNumber').on('change', function(){     let num = $(this).val().substr(13,1) %2          if(num){         $('#tortrix')         .removeClass('d-none')         .addClass('d-block form-control animated fadeIn')         .attr('value', function(i, oriVal){             if(num == 0) {                 console.log('ho')                 return 'value','Testatrix';             } else {                 console.log('hey')                 return 'value','Testator';              }         })     }         else if (num == "") {         $('#tortrix').removeClass('d-block').addClass('d-none')     } })

I'm using  to go through JavaScript, and it's returning many suggestions to replace == (two equals signs) with === (three equals signs) when doing things like comparing idSele_UNVEHtype.value.length == 0 inside of an if statement.  Is there a performance benefit to replacing == with ===?   Any performance improvement would be welcomed as many comparison operators exist.  If no type conversion takes place, would there be a performance gain over ==?


Anyone knows how to make an operator button that gets greyed out if two or more objects are not selected.

I have a panel with split column.  In the 2nd row is 3 boolean variables. I want to grey out the 2nd and 3rd option by default. I want the 2nd to be changeable if 1st is true, and 3rd to be changeable if both 1 and two are true. I've read something about "poll()" but not how to actually use it, or set conditions. Physics should only be enablable if singleMesh, and destructable only if physics enabled.      # Create two columns, by using a split layout.     split = layout.split()      # First column     col = split.column()     col.label(text="Building Size:")     col.prop(bpy.context.scene.user_vars, 'buildingHeight')     col.prop(bpy.context.scene.user_vars, 'buildingWidth')     col.prop(bpy.context.scene.user_vars, 'buildingDepth')      # Second column, aligned     col = split.column()     col.label(text="Dynamics:")     col.prop(bpy.context.scene.user_vars, 'singleMesh')     col.prop(bpy.context.scene.user_vars, 'enablePhysics')     col.prop(bpy.context.scene.user_vars, 'destructable_Building')  #EDIT This is what the specific solution to my example looks like. col = split.column() col.label(text="Dynamics:") col.prop(vars, 'singleMesh') sub = col.row() sub.enabled = vars.singleMesh sub.prop(vars, 'enablePhysics') sub = col.row() sub.enabled = vars.enablePhysics sub.prop(vars, 'destructable_Building')


When I choose to add Z or X, Y, Z function, "Add function surface" menu appears in the bottom-left corner. But once I click outside the object it disappears and I can no longer change the function. So how do I open that menu again to change the function or where can I find menu to redefine the function without adding new object whenever I want?

When you first add a cylinder, you have the option to change the number of vertices, etc, but once you do anything else in blender, it seems you no longer can edit those parameters.   Is there a setting anywhere or an add-on that allows these parameters to be edited later on? If not, how easy would such an addon/feature be to create for anyone reading this?


I have openjdk version "1.8.0_191" in my system. I need Oracle Java 7 for my project. I tried to install with following commands  sudo add-apt-repository ppa:webupd8team/java   sudo apt-get update sudo apt-get install oracle-java8-installer   But it is throwing the below error  Reading package lists... Done Building dependency tree        Reading state information... Done Package oracle-java7-installer is not available, but is referred to by  another package. This may mean that the package is missing, has been obsoleted, or is only available from another source  E: Package 'oracle-java7-installer' has no installation candidate    How to install the both version in my system? Thanks in Advance.

I want to install Oracle's JRE and to update to the latest version with the Software Updater when they released. Is there a Ubuntu package that is provided by Canonical or Oracle?  Before release Java 7, I followed  to install Java 6.  But it doesn't work for Java 7. There is no package sun-java7-xxx. How can you install Java 7?


This "new" functionality almost makes me regret buying a new Macbook. How on earth do I turn off the menu showing when the mouse hits the top? It's so incredibly annoying... I went full screen for a reason.

Pretty much every application I use in full-screen (including Firefox, MacVim and the Terminal) have tabs on the top of the screen.  The problem is, when I move my mouse to reach the tabs I'll often accidentally touch the top of the screen, bringing in the OS menu OVER the tabs:    Is there any way to change this behavior? I'd prefer it if the menu bar would stay hidden when I'm using a full-screen app, even if my mouse does touch the top of the screen.


Let $\varepsilon >0$. Let $N>?$. For any integer $n>N$ we have $$\frac{n^k}{2^n}<\varepsilon.$$ I don't know how to proceed here sensically.  I'd say we have to start with  $$<\frac{n^k}{2^N}$$  But what do we do here about the $n^k$?  Remember, I don't want to use l'Hopital or for me unproven limit laws like "exponents grow faster than powers"  Also, I don't want to use hidden l'Hopital, i.e. argumenting with derivatives. Since we don't even have proven derivative laws.

In other words, how to prove:  For all real constants $a$ and $b$ such that $a > 1$, $$\lim_{n\to\infty}\frac{n^b}{a^n} = 0$$  I know the definition of limit but I feel that it's not enough to prove this theorem.


In the following sentence, are both "sleep" and "be sleeping" correct? If so, what's the difference?  When can I leave? I should sleep / should be sleeping at home now.

Ok, see , here is this tense matrix                     Past - Present - Future Simple Continuous Perfect Perfect Continuous   We also have the same tense structures for Modals                     Can - May         - Might - Must - Could - Would - Ought to Simple                 may do Continuous             may be doing Perfect                may have done Perfect Continuous     may have been doing   I would think the differences between "must live in Japan" & "must be living in Japan" are:  Must here refers to a very high possibility. Things that you think is very likely to happen.  Ex: She must live in Japan (we also have "She lives in Japan" which means she lives there more or less permanently)  And when you want to emphasize a continuous process, say "She must be living in Japan" (we also have "She is living in Japan" which means she lives there more or less temporarily)  Ok, "must, might" are easy, but what about "should"?  My question is that: What are the differences between "I should live in Japan" & "I should be living in Japan"?  Does "I should live in Japan" mean "I should live there more or less permanently"  & "I should be living in Japan" mean "I should live there more or less temporarily"?  Note: "must" here refers to possibility not obligation. She must live in Japan (=it is likely that she lives there at this moment), not (She have to live there) as if it is obligation  "should" here refers to advice.


I've lost the thumbdrive that had the image on it. Is there some way to reinstall without one?  E: It's a reinstall over an existing ubuntu install. Windows issues really aren't all that relevant.

I want to install Ubuntu on my laptop that doesn't have a CD-ROM drive and I have no spare USB disk. I've tried Wubi, but that doesn't seem to work (since it prompts me to have the CD in the drive, which I don't have).  How can I install Ubuntu, easily and in a fast way?  P.s: I want to dual boot it with Windows 7 (which was preinstalled).  Edit:   When extracting the ISO to a folder and running Wubi it does install, but when I reboot the computer, it doesn't show GRUB, nor can I choose if I want to boot Ubuntu or Windows 7. After trying for the third time today, wubi gives me an error: Permission denied   I'm the administrator on the PC.


Newbie here. I've looked through the answers to similar questions and am both in awe and perplexed by what I see. While I am sure that once I get the lingo down (solidify, mesh, remesh) it will all make sense, however I find that I have an urgent requirement and I'm only part way through the learning flow.  I need to create a few atoms. Quite simple really as far as I can tell, but I'm not there yet in the learning. I need a sphere with "H" on it (I guess the secret of which element it is is out).   There's a really good answer, apparently, on a question about creating balloons with text, but the language (peel off the pelt etc) used is well beyond me. Is there a location I should be looking to learn how to slap text onto a sphere?

I am fairly new to blender and I am trying to do something which I am assuming is fairly straight forward with no success. All I'm looking to do is emboss some text onto the curved part of a yogurt pot. Image attached below. What is the quickest and easiest way of doing this?  Thanks in advance


We want to install Ubuntu on a , which had Windows 10 on it. We created a bootable USB, and followed the install instructions. It went well and at the end it asked us to restart. Since then it returns different errors and it does not even come up. We are not able to use the laptop any more. We do not have Windows anymore since we wiped it out during the installation.  Solution:  In the bootable USB, go to folder /boot/efi and rename the file grubx64.efi to mmx64.efi  Restart into the UEFI settings and change the controller to AHCI instead of Intel RST Premium  Updated the BIOS, install the latest update

I am trying to boot Ubuntu on my computer.  When I boot Ubuntu, it boots to a black screen.  How can I fix this? Table of Contents:


This is a question about the process of developing an addon rather than a specific error in the script. I'm creating an Operator that I want to show up in the UV Unwrap menu.  I'm editing the script in the Scripting tab and every time I want to try the latest version of my code, I press the little arrow button to run my script. Unfortunately, every time I do a new entry is added to my menu list, so over a programming session my menu quickly fills up with lots of identical entries to run my operator.  I just want a single menu entry.  I thought my operators unregister() method would take care of this, but it does not seem to. What would be a better workflow to develop my addon? import bpy from bpy.props import FloatProperty  class UnwrapWorldUvOperator(bpy.types.Operator):     bl_idname = "uv.unwrap_world_space"     bl_label = "Unwrap World Space Operator"     bl_options = {'REGISTER', 'UNDO'}      scale: FloatProperty()      @classmethod     def poll(cls, context):         obj = context.active_object         return obj and obj.type == 'MESH' and obj.mode == 'EDIT'      def execute(self, context):         print (self.bl_idname)         return {'FINISHED'}  def menu_func(self, context):     self.layout.operator("uv.unwrap_world_space")      def register():     bpy.utils.register_class(UnwrapWorldUvOperator)     bpy.types.VIEW3D_MT_uv_map.prepend(menu_func)   def unregister():     bpy.utils.unregister_class(UnwrapWorldUvOperator)     bpy.types.VIEW3D_MT_uv_map.remove(menu_func)   if __name__ == "__main__":     register()

Is there a way to use the Blender Text Editor for adding a custom menu and not get a duplicate every time I click on "Run Script" to test the menu? For example, in the text editor, load the template like so:  Template -> Python -> UI Menu  Then notice every time you press "Run Script" you get another menu in your main menu bar. How can I update my menu without getting a duplicate?  I tried simply commenting out register() but then new updates don't show up.


I was reading Ivor Horton's Beginning Visual C++ 2008 and many of its CLR examples have this definition for main:  int main(array<System::String ^> ^args)   I went back, page by page, to the beginning of the book to find the first such instance with an explanation what it really means, but couldn't find one.  Obviously it means the same as the standard int main(int argc, char *argv[]), but I'd like to know when and why that ^ is really used, and why it even exists (does it do something that pointers * and references & cannot represent)?

I just came across this code and a few Google searches turn up no explanation of this mysterious (to me) syntax.  Hashtable^ tempHash = gcnew Hashtable(iterators_);  IDictionaryEnumerator^ enumerator = tempHash->GetEnumerator();   What the heck does the caret mean? (The gcnew is also new to me, and I asked about that .)


I have some initial data to insert in my database. I've added it to my custom SQLiteOpenHelper class.  package com.company.database;  import android.content.Context; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteOpenHelper;  public class MySQLiteOpenHelper extends SQLiteOpenHelper {     public static final String TABLE_NAMES = "names";     public static final String COLUMN_ID = "_id";     public static final String COLUMN_NAME = "name";      private static final String DATABASE_NAME = "my.db";     private static final int DATABASE_VERSION = 1;      private static final String TABLE_NAMES_CREATE = "CREATE TABLE " + TABLE_NAMES + "("             + COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, "             + COLUMN_NAME + " VARCHAR NOT NULL);";      private static final String TABLE_NAMES_INSERT = "INSERT INTO " + TABLE_NAMES             + "(" + COLUMN_NAME + ")" + " VALUES "             + "('Antony'),"             + "('Benny'),"             + "('Carol'),"             + "('Daniel'),"             // ... AND SO ON ...      public MySQLiteOpenHelper(Context context) {         super(context, DATABASE_NAME, null, DATABASE_VERSION);     }      @Override     public void onCreate(SQLiteDatabase database) {         database.execSQL(TABLE_NAMES_CREATE);     }      @Override     public void onUpgrade(SQLiteDatabase database, int oldVersion, int newVersion) {         dropTable(database);         onCreate(database);     }      private void dropTable(SQLiteDatabase database) {         database.execSQL("DROP TABLE IF EXISTS " + TABLE_NAMES);     } }   Please note the insert statements. The quantity of names will increase and i don't want to keep this mess.  What should i do to fix it?

If your application requires a database and it comes with built in data, what is the best way to ship that application? Should I:   Precreate the SQLite database and include it in the .apk? Include the SQL commands with the application and have it create the database and insert the data on first use?   The drawbacks I see are:   Possible SQLite version mismatches might cause problems and I currently don't know where the database should go and how to access it. It may take a really long time to create and populate the database on the device.   Any suggestions? Pointers to the documentation regarding any issues would be greatly appreciated.


I've seen this question for older versions of the Mac mini, but I'm struggling to find an answer for the Mac mini 2018.  I want to connect 3 identical monitors (22inch 1080p). I'm currently able to connect 2 monitors using HDMI-Thunderbolt 3 cables, but I'm unable to get the 3rd monitor to detect a signal. I have a 3rd HDMI-Thunderbolt 3 cable, and I also have a VGA to HDMI adapter I can use as well.  If I plug the VGA-HDMI cable into he HDMI port on the Mini, the two functioning monitors begin to flicker. The third monitor is still not detecting a signal.   The monitor is a 1920x1080, 75 Hz  Has anyone successfully configured a 2018 Mac Mini to 3 monitors using one of these configurations?  Thanks!

It seems the new Mac Mini uses both HDMI and Thunderbolt, but bandwidth limitations of Thunderbolt may prevent using 3 daisy-chained Thunderbolt high resolution monitors such as the newly released Apple Thunderbolt 27" Display, limiting you to two instead of three.  If this correct: 1. What occurs to the 3rd monitor in a triple daisy-chain? Black screen? Reduced available resolution up to the bandwidth limit of Thunderbolt? 2. Are there HDMI to mini-displayport adapters for connecting the HDMI output of the Mini to the Thunderbolt input of an Apple Thunderbolt 27" Display? Would that even work?


The  is described as:     earn 150 reputation points on three different sites (not including Stack Overflow) within 15 days.   Does the +100 site association bonus count towards the required 150?

From       Running Ragged      earn 150 reputation points on three different sites (not including   Stack Overflow) within 15 days.   So my query is: association bonus going to be counted for it?


I once came across a word in English that is used to describe the following situation:  When a word in one language means something rude when pronounced the same way in another language. An example could be "kiss" in English which means "Pee" in Swedish.  I've desperately tried to find out what that word is but with no luck.  Can anyone help?

examples:         Gift (German) = poison   poisson (French) = fish   embarazada (Spanish) = pregnant   sauce (Spanish) = willow   triviale (Italian) = vulgar   parentes (Portuguese) = relatives   slim (Dutch) = smart


Ubuntu gives black screen at startup. I  have no idea why.  Maybe it's the  software update I did yesterday? Why is it happening?

I updated from 14.04 to 16.04 and used katoolin to add some Kali tools. After restart, the boot up of Linux ran codes, but stopped at a certain point never to load login. So I reinstalled 16.04, ran updates and tried again. This time, the boot menu was changed to Kali as well as the OS name (I'm using Windows 7 dual boot with Ubuntu); login started in Ubuntu style without user name, had to type in the name... then it goes to the logo screen never to log in.  How can I use katoolin without it affecting the boot menu interface? Does this happen when the user selects the option 'add Kali repositories and updates'? Are the Kali repositories necessary? I'd much rather just install the tools and not mess with the Ubuntu interface.


A part of my htaccess that redirects HTTP traffic to HTTPS looks like this:  RewriteCond %{HTTP:X-Forwarded-Proto} !https RewriteRule ^.*$ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]   I need allow some pages (lets say /page1, /page2) be HTTP only. Thanks!

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


Why my defaultTableModel undergo nullPointerException?   private void jYearChooser1PropertyChange(java.beans.PropertyChangeEvent evt) {         try {             dtm.setRowCount(0);//NullPointerException             ArrayList<Salary> salaries = SalaryController.getSalaries(jYearChooser1.getYear(), jMonthChooser1.getMonth() + 1);             for (Salary salary : salaries) {                 Employee employee = EmployeeController.searchEmployee(salary.getEmployeeId());                 Object[] rawData = {salary.getEmployeeId(), employee.getFirstName() + " " + employee.getSecondName(), salary.getTotalEarnings(), salary.getTotalDeductions(), salary.getNetSalary()};                 dtm.addRow(rawData);             }         } catch (ClassNotFoundException | SQLException ex) {             Logger.getLogger(ViewSalary.class.getName()).log(Level.SEVERE, null, ex);         }      }

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


I am making a zombie game and as I was making it I noticed the zombie AI starts to clump up into one mega zombie in one area. I was wondering how I could keep the zombies from doing that and instead make a horde like formation. I don't know how I would implement this and I don't know where to put it in my game logic so if you could give me some ideas or hints that would be fantastic.  Thanks in advance!

For intentional reasons, certain units in the game I'm currently programming don't have any collision detection and response among each other.   This enables them to clutter right on top of each other. This is a wanted behavior, since there will be situations in the game when the player does want them to stack like that.  However, I want to make the process of uncluttering them easy for the player, so that they just have to press a hotkey or click some button on the screen and have the units disperse just enough so it's easy to select a group of them with the mouse (if they stand on top of each other one mouseclick selects all units).  How could I do this without running a brute force N^2 nearest neighbor search on all units?


Say we have an expression of the form: $$ \left<0\right|:\phi(x)^2: : \phi(y)^2:\left|0\right>, $$ where $\phi$ is some scalar field. I have heard the claim several times, that in evaluating this expression using Wick contractions, one only has to contract terms between groups of normal ordered terms. In this example this would mean we only have to contract $\phi(x)$ with $\phi(y)$ but not $\phi(x)$ with $\phi(x)$. I have no clue how to derive this. Has anyone got an idea?  EDIT: And say we consider anticommuting operators, would we have: $$ \left<:\Psi^{\dagger}(x)\Psi(x)::\Psi^{\dagger}(0)\Psi(0):\right> = (-1)^3\left<\Psi^{\dagger}(x)\Psi(0)\right>\left<\Psi^{\dagger}(x)\Psi(0)\right>, $$ or with a plus sign?

Let $\phi$ be a scalar field and then I see the following expression (1) for the square of the normal ordered version of $\phi^2(x)$.   \begin{align} T(:\phi^2(x)::\phi^2(0):) &= 2 \langle 0|T(\phi(x)\phi(0))|0 \rangle^2 \\ &+ 4\langle 0|T(\phi(x)\phi(0))|0 \rangle:\phi(x)\phi(0): \\ &+ :\phi^2(x)\phi^2(0): \tag{1} \end{align}  It would be great if someone can help derive the above expression - may be from scratch - and without outsourcing to Wick's theorem - and may be help connect as to why the above is related (equal?) to the Wick's theorem?    Isn't the above also known as OPE (Operator Product Expansion)? If yes, then is there at all any difference between OPE and Wick's theorem? Is there a systematic way to derive such OPEs?  Can one help extend this to Fermions?


I read a book in the 90s about mind control, but can't remember the title or the author.  People start to commit extremely violent crime for no apparent reason. They claim that they had no control over their body when the crime was committed. Somebody who seems to be Russian-speaking is controlling them.  After being convicted of pretending to be controlled, the main hero ends up on an island where he discovers that the people in charge of the island are responsible for the chaos.  Russian scientists have invented a body controlling device. They used the device to escape the Soviet world. Now that renegade group is abusing the device and wrecking the entire world.  If I remember correctly the hero defeated the bad guys. However despite his initial promise, in the end he could not give up the high that the device gave him.  Any idea what is title of that book and who wrote it?

I read this story many years ago and now can't remeber who wrote it or even what it was called. The story was about a group of elite humans who had access to a headdress that allowed them to control another human, even if they were thousands of miles away.  They could use this ability to commit crimes, etc.  I think the cover may have been yellow like those published by Gollancz.


I'm new to the use of Java with database connections, but am getting a NullPointerException using the following code:   import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.util.ArrayList;   public ArrayList<UserVO> getAllUsers(Connection connection) throws Exception {             ArrayList<UserVO> userList = new ArrayList<UserVO>();             try {                 PreparedStatement ps = connection.prepareStatement("SELECT * FROM user");                 ResultSet rs = ps.executeQuery();                 while (rs.next()) {                     UserVO uservo = new UserVO();                     uservo.setUsername(rs.getString("username"));                     uservo.setPassword(rs.getString("password"));                     userList.add(uservo);                 }                 return userList;             } catch (Exception e) {             throw e;             }         }      }   At  PreparedStatement ps = connection.prepareStatement("SELECT * FROM user");   the code throws an exception for java.lang.NullPointerException.I don't know why this is happening, as a   System.out.println("isClosed = " + connection.isClosed());   before the PreparedStatement declaration returns false, and I can print out the connection info.   Any idea of the cause or how to properly compose a statement before query execution? Thanks!  EDIT: Full(ish) stack trace - it's very long  java.lang.NullPointerException     at com.mysql.jdbc.PreparedStatement.asSql(PreparedStatement.java:649)     at com.mysql.jdbc.PreparedStatement.asSql(PreparedStatement.java:587)     at com.mysql.jdbc.PreparedStatement.toString(PreparedStatement.java:4068)     at java.lang.String.valueOf(String.java:2994)     at java.lang.StringBuffer.append(StringBuffer.java:263)     at com.mysql.jdbc.trace.Tracer.printParameters(Tracer.aj:240)     at com.mysql.jdbc.trace.Tracer.printEntering(Tracer.aj:167)     at com.mysql.jdbc.trace.Tracer.entry(Tracer.aj:126)     at com.mysql.jdbc.trace.Tracer.ajc$before$com_mysql_jdbc_trace_Tracer$1$f51c62b8(Tracer.aj:45)     at com.mysql.jdbc.Connection.registerStatement(Connection.java)     at com.mysql.jdbc.Statement.<init>(Statement.java:270)     at com.mysql.jdbc.PreparedStatement.<init>


Suppose $\sum{a_n}$ converges. How do I prove that $\sum{\frac{\sqrt{a_n}}{n}}$ converges.  So I know that just because  $\sum{a_n}$ converges, do not mean I can say anything about the converges of its square root. So I know that I can prove that if  $\sum{\sqrt{a_n}}$ converges then $\sum{\frac{\sqrt{a_n}}{n}}$ converges by Abel's Test, but I do not know where to start for the case where  $\sum{\frac{\sqrt{a_n}}{n}}$ diverges

I need help to solve following problem from Rudin's Mathematical analysis book:    Convergence of the series $\sum a_n$  implies the convergence of $\sum \dfrac{\sqrt {a_n}}{n}$, if $a_n>0$  I tried to construct a suitable convergence sequence $b_n$ such that $\sum b_n$ converges and $a_n \leq b_n$ but, I am not able to find such sequence $b_n$ .  Thanks for the help and sugestions.


why name of array "list" first printed as reference and second code printed content of it. int[] list = new int[5]; list[0] = 1; list[1] = 2; System.out.println(list);  It prints the reference [I@4dd8dc3 and i know that i should use for loop to iterate over elements. But why there is in other code gives me the content not the address? Is that specific for generics? ArrayList<Integer> list = new ArrayList<>(); list.add(1); list.add(2); System.out.println(list);  that prints [1, 2]

In Java, arrays don't override toString(), so if you try to print one directly, you get the className + '@' + the hex of the  of the array, as defined by Object.toString():  int[] intArray = new int[] {1, 2, 3, 4, 5}; System.out.println(intArray);     // prints something like '[I@3343c8b3'   But usually, we'd actually want something more like [1, 2, 3, 4, 5]. What's the simplest way of doing that? Here are some example inputs and outputs:  // Array of primitives: int[] intArray = new int[] {1, 2, 3, 4, 5}; //output: [1, 2, 3, 4, 5]  // Array of object references: String[] strArray = new String[] {"John", "Mary", "Bob"}; //output: [John, Mary, Bob]


please refer to the following scenarios:    and     The first case is generated by the following part of the script:  \question[5+2]         Let $ (X,d) $ be a metric space and $ A\subseteq X $. \textit{Boundary} of $ A $ is defined as $ \partial A=\bar{A}\setminus A^{\circ} $. Show that,         \begin{parts} %3.a.             \part[5]                 \[ \begin{array}{rcl}                 \partial A  &=& (A^{\circ}\cup \ext A)^{c}\\[1ex]                 &=& \{x\in X:\forall\d>0, N_{\d}(x)\cap A\ne\emptyset\text{ and }N_{\d}(x)\cap A^{c}\ne\emptyset\}.                  \end{array} \tag*{\parbox{1pt}{\droppoints}} \]   and the second instance is generated by   \question[5+2]         Let $ (X,d) $ be a metric space and $ A\subseteq X $. \textit{Boundary} of $ A $ is defined as $ \partial A=\bar{A}\setminus A^{\circ} $. Show that,         \begin{parts} %3.a.             \part[5]                 $\begin{array}{rcl}                 \partial A  &=& (A^{\circ}\cup \ext A)^{c}\\[1ex]                 &=& \{x\in X:\forall\d>0, N_{\d}(x)\cap A\ne\emptyset\text{ and }N_{\d}(x)\cap A^{c}\ne\emptyset\}.                  \end{array}$\droppoints   What I want is to align the first line of the array with the question number (a). How can I achieve that?  I am using exam class. Here is my preamble.  \documentclass[a5paper,11pt]{exam} \usepackage[left=0.25in,right=0.75in,top=0.5in,bottom=0.5in,footskip=.15in]{geometry} \usepackage{amsmath, amssymb, amsthm, amsfonts} \usepackage[english]{babel} \usepackage{mathtools} \usepackage[inline]{enumitem} \usepackage{mathrsfs} \usepackage{nccmath} \usepackage{stmaryrd} \usepackage{mathdots} \usepackage{lastpage,refcount} \footer{}{\small\thepage}{\ifodd\value{page}\relax     \if\thepage\getpagerefnumber{LastPage}\relax     \else \tiny {\mbox{\kern\dimexpr+4.75in\relax}}\boxed{\textbf{Turn Over}}     \fi     \fi} \usepackage{etoolbox} \makeatletter \setlength\@rightmargin{0.5in} \patchcmd\setup@point@toks{\llap{\padded@point@block}}{\rlap{\padded@point@block}}{}{} \patchcmd\droppoints{\llap{\padded@point@block}}{\rlap{\padded@point@block}}{}{} \patchcmd\droptotalpoints{\llap{\total@block}}{\rlap{\total@block}}{}{} \patchcmd\droptotalbonuspoints{\llap{\bonustotal@block}}{\rlap{\bonustotal@block}}{}{} \makeatother   \marksnotpoints \bracketedpoints \pointsdroppedatright   \renewcommand\partlabel{(\textbf{\alph{partno}})} \renewcommand{\thesubpart}{(\textit{\roman{subpart}})} \renewcommand{\subpartlabel}{\thesubpart} \renewcommand\questionlabel{\textbf{\thequestion.}}  \newcommand{\R}{\mathbb{R}} \newcommand{\N}{\mathbb{N}} \newcommand{\Q}{\mathbb{Q}} \newcommand{\Z}{\mathbb{Z}} \renewcommand{\a}{\alpha} \renewcommand{\b}{\beta} \newcommand{\g}{\gamma} \renewcommand{\d}{\delta} \newcommand{\e}{\epsilon} \DeclareMathOperator{\interior}{int} \DeclareMathOperator{\ext}{ext} \newcommand{\abs}[1]{\left\lvert #1 \right\rvert} \newcommand{\norm}[1]{\left\lVert #1 \right\rVert}

I have an array which has a few columns, and each of the columns contains again an array. The problem is that the three arrays are vertically aligned with respect to the center. How to align them on the top?  Here is a simple example  \documentclass[12pt]{amsart} \begin{document} \[\begin{array}{llll} \begin{array}{|l|l|l|} \hline a& b& c\\ \hline 1&1&0\\1&2&3\\ 4 & 5& 6\\ \hline\end{array}& \begin{array}{|l|l|l|} \hline a& b& c\\ \hline 1&3&4\\1&2&3\\  4&5&6\\ 7&9&8\\ \hline\end{array}& \begin{array}{|l|l|l|} \hline a& b& c\\ \hline 1&2&5\\1&2&3\\ \hline\end{array}\end{array}\] \end{document}   which gives    but I would like to have something like this:    Thanks for your help.


I feel like someone made a comment as an answer on a question with a bounty just so they could reap the "auto bounty" since they are the only answer on it.   I've flagged the bad/useless answer (as a non-answer) for moderator review but the bounty will be assigned automatically in less than 24hrs and I feel like this guy/gal is just trying to cheat the system.   All I'm trying to do is ensure the bounty simply expires and the guy/gal that was trying to cheat the system by putting down a useless guess doesn't get it.   I've answered my own question (properly) and marked it as the accepted answer, not sure if that makes a difference though in this person still cheating the system since I'm the OP and created the accepted answer.   Here is the post:

It's possible to offer and award bounties of reputation on questions.   What is a bounty? How can I find questions that have a bounty attached? How do I start a bounty? When can I start a bounty? Why is the system requiring me to choose a bounty amount that's higher than the minimum? Can I use Markdown formatting in the bounty remarks? Can I edit the remark? How long is the bounty period? How do I award a bounty? Can I award a bounty to my own answer? Can I award a bounty to an old answer? If I offer a bounty on someone else's question, can I award the bounty to their answer? After awarding the bounty, can I remove it or move it to another answer at a later time? What happens if there's no answer after the bounty period? What happens if I feel my question is still unanswered? What is automatic awarding? Are bounty awards exempt from the 200 points/day reputation limit? How does Community Wiki mode affect bounties? How does user deletion or post dissociation affect bounties? Can I award a bounty to an answer from a deleted user or one where the author was dissociated? Can I offer a second bounty after the first one has expired? Can I raise my bounty? What happens if a bounty question is closed or deleted? Why can't I vote to close or migrate a bounty question? What happens if I delete my account while I have an active bounty? Do I keep an awarded bounty when I delete my answer? What happens if a question where I awarded a bounty later gets deleted or migrated? Can I cancel my bounty? Can I affect / divide / share part of my bounty to two (or more) users? How many outstanding bounties can a single user have?      See also:  in the Help Center


I know I can become root (super user) via the su command but I have to authorize it after entering the commands. Is there a way I can become root and authorize (with password) in one line

How does the ubuntu user on the AWS images for Ubuntu Server 12.04 have passwordless sudo for all commands when there is no configuration for it in /etc/sudoers?  I'm using Ubuntu server 12.04 on Amazon. I want to add a new user that has the same behavior as the default Ubuntu user. Specifically I want passwordless sudo for this new user.   So I've added a new user and went to edit /etc/sudoers (using visudo of course). From reading that file it seemed like the default ubuntu user was getting it's passwordless sudo from being a member of the admin group. So I added my new user to that. Which didn't work. Then I tried adding the NOPASSWD directive to sudoers. Which also didn't work.   Anyway, now I'm just curious. How does the ubuntu user get passwordless privileges if they aren't defined in /etc/sudoers. What is the mechanism that allows this?


The java.util.List.contains(Object o) method takes Object as an argument and internally uses Object.equals(Object o) as described .  If I do the following code in Netbeans:   List<String> listStr = new ArrayList<>();  listStr.contains(34); //warning   it gives the obvious warning, that is:  Given object can not contain instances of int (expected String)   Since it visible to all, that String never be equal to int then why shouldn't it take Element type E (in my case String) as an argument instead of Object?

Why isn't  generic?    Seems like Collection<E> could have boolean remove(E o);   Then, when you accidentally try to remove (for example) Set<String> instead of each individual String from a Collection<String>, it would be a compile time error instead of a debugging problem later.


The Spectrum of a bounded operator on a Banach space $X$ is always a compact subset of $\mathbb{C}$. What about the converse?  Given any compact subset $K \subset \mathbb{C}$ is it always possible to find a Banach space $X$ and a bounded operator $T: X \to X$ such that $\sigma(T) = K$ ? Is there one Banach space which works for any $K$ ?  I think for countable $K = \{\lambda_0, \lambda_1, \dots\}$ this is always possible: The operator $T: \ell^2 \to \ell^2, (x_0, x_1, \dots) \mapsto (\lambda_0 x_0, \lambda_1 x_1, \dots)$ is bounded and has all elements of $K$ as eigenvalues.

Let $A\subset \mathbb{C}$ be a compact subset.   Since $A$ is compact and metric space, it is separable, say $\overline{\lbrace a_n\rbrace_{n=1}^\infty}=A$.   Let $\mathcal{l}^2(\mathbb{Z})$ be the Hilbert space consisting of $L^2$-summable sequences and $\lbrace e_n\rbrace_{n=1}^\infty$ be the canonical basis of $\mathcal{l}^2(\mathbb{Z})$.  Define an operator $T\colon\mathcal{l}^2(\mathbb{Z})\to\mathcal{l}^2(\mathbb{Z})$ by sending $e_n$ to $a_ne_n$. I want to prove that $A=\sigma(T)$, where $\sigma(T)$ is the spectrum of $T$.   What I can prove is that $A=\overline{\lbrace a_n\rbrace_{n=1}^\infty}\subset \sigma(T)$ because each $a_n$ is an eigenvalue of $T$ and $\sigma(T)$ is closed. How can I prove the other inclusion, namely $\sigma(T)\subset A$?


I am getting nullpointerexception when i call the putArray()and sortArray() methods. getArray() method works fine. when i print the array within getArray() method it is working. But i get null pointer exception when i print in putArray() method.I spent a lot of time figuring it out .Kindly help me resolve this. also suggest me any other better ways to write this code. Thank you.  import java.util.Scanner; public class BubbleSort {     int num;     int[] arr;     public void getArray() {         System.out.print("Enter the total numberr of elements in the Array :  ");         Scanner sc = new Scanner(System.in);         num = sc.nextInt();         int arr[] = new int[num];         System.out.print("Enter " + num + " Elements  : ");         for (int i = 0; i < num; i++) {             arr[i] = sc.nextInt();         }     }     public void putArray() {         System.out.print("The Array is:  ");         for (int i = 0; i < num; i++) {             System.out.println(arr[i] + "  ");         }     }     public void sortArray() {         for (int i = 0; i < num; i++) {             boolean flag = false;             for (int j = 0; j < num - i - 1; j++) {                 if (arr[j] > arr[j + 1]) {                     arr[j] = arr[j] + arr[j + 1];                     arr[j + 1] = arr[j] - arr[j + 1];                     arr[j] = arr[j] - arr[j + 1];                     flag = true;                 }             }             if (!flag) {                 break;             }         }     }     public static void main(String[] args) {         BubbleSort b = new BubbleSort();         b.getArray();         b.putArray();         b.sortArray();         b.putArray();     } }

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


I have been actively using Stack Exchange app for some days now.  In my account page, in the place of userID, it says user470992. How can I change it to something of my choice. I am using the app in Android platform.  Please provide step by step solution.  Also, how do I log into Stack Exchange in my other devices with this account?

It would be nice to update the profile page from within the app.  Perhaps not many people update their profiles more frequently, but when required to do so, I would prefer to do it from the app instead of the mobile browser.


I know this has likely been asked before but I've not been able to find any solutions.  Let me explain my "issue"  I have a custom windows 7 visual style which makes all of my explorer windows dark and simple, pic related:    I love this theme I've created, and I'd like for these darker windows 7 frames to be used as a replacement to the Chromium/Chrome windows.  I think chromium is great, I love using it and I've tried alternatives (Opera, IE) both of these browsers have their own issues   (stuttering & slow in comparison to chromium OR limited to zero customization without sacrificing some modern functionality.)   Opera 12 is the best solution I found and I guess it does exactly what I want boy does it lag... hard.   However, both of those browsers DO extend the basic windows 7 frames. (the frames that every other explorer application uses, excluding things like Microsoft Office, Photoshop or Visual Studio which use their own custom frames)  I was wondering if there was ANY WAY AT ALL to somehow disable the Chromium/Chrome custom frames in favor of the default Windows 7 frames used by all other applications.  Also, bonus question, is there any way to get H.2XX video (HTML 5) to work with Chromium?  Not a duplicate since the issue hasn't been resolved.

Is there a way to disable Chrome's custom window skinning such that it lets the OS draw standard window title bars, borders, etc, in the style I have configured the OS to draw such things with?  I didn't spend all that time with the control panel setting a window style that pleases me just to have applications decide that they know better than me how I want my windows to look. As a practical matter, having each application decide for itself which color cues to use to show "this is the active window" becomes very confusing.  Alternatively, is there a tool somewhere that reads the Windows 7 color and window style settings and produces a Chrome theme that imitates them?


The  is supposed to be awarded to users who "vote on 12/15". But it was awarded to me on several sites immediately at 00:00 UTC on 12/15.    I didn't even visit these sites on 12/15 yet!

During Winter Bash, users can earn hats. But sometimes it seems that a hat was awarded even though its requirements weren't (yet) met, or vice versa.  What could be the reason for this?


How to calculate the positions of all 5 Lagrange Points between Sun and Earth? (Please give solution for all points especially for L4 and L5)

According to , there are 5 equilibrium, or  of the Earth-Moon system and only 2 of them are said to represent stable equilibrium points.     This made me think if there is an equation that describes this system, and from which Physics Laws was it derived?


I want to retrieve image from firebase store using the alert dialog with recycle view but it always returns a message error. I can upload an image to firebase store, but to upload it I want it to retrieve alert dialog. I still confusing about the adapter for alert dialog  This is the error message that I get after run the application:  java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.widget.RecyclerView.setHasFixedSize(boolean)' on a null object reference   This is my AlertDialog function in DisplayAllActivity:  private RecyclerView mRecycleView; private ImageAdapter mAdapter; private List<Upload> mUpload;  private void showUpdateDialog(){      AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(this);      LayoutInflater inflater = getLayoutInflater();      final View dialogView = inflater.inflate(R.layout.location_dialog, null);      dialogBuilder.setView(dialogView);      mRecycleView = findViewById(R.id.recycler_view);     mRecycleView.setHasFixedSize(true);     mRecycleView.setLayoutManager(new LinearLayoutManager(this));      mUpload = new ArrayList<>();      databaseReference = FirebaseDatabase.getInstance().getReference("Upload");      databaseReference.addValueEventListener(new ValueEventListener() {         @Override         public void onDataChange(@NonNull DataSnapshot dataSnapshot) {             for (DataSnapshot postSnapshot : dataSnapshot.getChildren()){                 Upload upload = postSnapshot.getValue(Upload.class);                 mUpload.add(upload);             }              mAdapter = new ImageAdapter(DisplayAllActivity.this, mUpload);              mRecycleView.setAdapter(mAdapter);         }          @Override         public void onCancelled(@NonNull DatabaseError databaseError) {             Toast.makeText(DisplayAllActivity.this, databaseError.getMessage(), Toast.LENGTH_SHORT).show();         }     });      final AlertDialog alertDialog = dialogBuilder.create();     alertDialog.show();  }   Here is my ImageAdapter java class for the image to be retrieved form firebase store  public class ImageAdapter extends RecyclerView.Adapter<ImageAdapter.ImageViewHolder> {  private Context mContext; private List<Upload> mUploads;  public ImageAdapter(Context context, List<Upload> uploads) {     mContext = context;     mUploads = uploads; }  @NonNull @Override public ImageViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {     View v = LayoutInflater.from(mContext).inflate(R.layout.image_location_image, viewGroup, false);     return new ImageViewHolder(v); }  @Override public void onBindViewHolder(@NonNull ImageViewHolder imageViewHolder, int i) {     Upload uploadCurrent = mUploads.get(i);     imageViewHolder.textViewName.setText(uploadCurrent.getName());     Picasso.get().load(uploadCurrent.getImageUrl()).fit().centerCrop().into(imageViewHolder.imageView); }  @Override public int getItemCount() {     return mUploads.size(); }  public class ImageViewHolder extends RecyclerView.ViewHolder {      public TextView textViewName;     public ImageView imageView;      public ImageViewHolder(@NonNull View itemView) {         super(itemView);          textViewName = itemView.findViewById(R.id.text_view_name);         imageView = itemView.findViewById(R.id.image_view_upload);      } }}   This is XML for RecycleView that will be used by the ImageAdapter to display the image from firebase store.  <android.support.v7.widget.RecyclerView     android:id="@+id/recycler_view"     android:layout_width="match_parent"     android:layout_height="match_parent" />


I have encountered with this equation while solving an integral. The integral result was $$ \left. \sum_{n=0}^{m+1} \left( \frac{d^n}{d x^n}\left( x^{m-1}\prod_{k=1}^{2}\left(\lambda_{k}.x+m(1-\lambda_{k})\right)\right)\right)\right|_{x=0}=m\lambda_{1}\lambda_{2}+m^2 $$ where $m$,$\lambda_{1}$ and $\lambda_{1}$ are positive constants. Now suppose I have $m_1$ and $m_2$, then I have $$ \left. \sum_{n=0}^{N} \left( \frac{d^n}{d x^n}\left( f(x) \right)\right)\right|_{x=0}=m_{1}\lambda_{1}\lambda_{2}+m_{1}m_{2} $$ What is the value of $N$ and function $f(x)$ that satisfies the previous equation. Or what should we modify on the first equation to meet the last one. Note: $m_{1}\neq m_{2}$.

I want to solve this differential equation evaluted at $x=0$. I will start with an example with $m=2$ $$ f(0)+f'(0)+f''(0)=2\lambda_{1}\lambda_{2}+4 $$ where $m$,$\lambda_{1}$ and $\lambda_{1}$ are positive constants. The $f(x)$ that satisfies the previous equation is $$ \prod_{k=1}^{2}\left(\lambda_{k}.x+2(1-\lambda_{k})\right) $$ I have encountered with this equation while solving an integral. The result was $$ \left. \sum_{n=0}^{m+1} \left( \frac{d^n}{d x^n}\left( x^{m-1}\prod_{k=1}^{2}\left(\lambda_{k}.x+m(1-\lambda_{k})\right)\right)\right)\right|_{x=0}=m\lambda_{1}\lambda_{2}+m^2 $$ So I want to find f(x) that satisfies $$ \left. \sum_{n=0}^{m+1} \left( \frac{d^n}{d x^n}\left( f(x) \right)\right)\right|_{x=0}=m_{1}\lambda_{1}\lambda_{2}+m_{1}m_{2} $$ Note: $m_{1}\neq m_{2}$.


Let  $ ABCD $ be a square with side length $ a $. Let $ s $ be a staircase from $ A $ to $ C $ with total length $ l $ and number of steps $ n $. It consists of perpendicularly alternating lines of length $ \frac{a}{n} $, as .  We see that $ l $ can be expressed as follows: $$ l = \frac{a}{n} \cdot n + \frac{a}{n} \cdot n = \frac{a}{n} \cdot n \cdot 2 = 2a $$ and as such stays constant at $ 2a $.  Now let us imagine that the amount of steps is infinite, e.g. $ n =  \infty  $. Per definitionem, the staircase should now be the diagonal of the square with length $ l=a\sqrt{2} $ according to Pythagoras. This is paradoxical! According to the equation pictured above, it should have the length $ 2a $, not $ a\sqrt{2} $.  My question is:  Does $ l $ equal to $ 2a $ or $ a\sqrt{2} $?

What is wrong with this proof?    Is $\pi=4?$


I am working on a scene in blender related to Minecraft but for some reason my render image have small yellow and red spots sprinkled which are barely noticeable , is their a way to fix it. it might be a problem with cycles as it works fine with eevee.

I often use Cycles' built in Glass BSDF shader to achieve realistic refraction effects, but in many cases, it seems that Cycles' glass caustics creates an unfortunately large number of fireflies (pixels that are abnormally bright relative to their surroundings). In some models of mine, even when I render for 3000 or more samples/pixel, my final image is still covered in fireflies. While I can improve this in many cases by increasing the total amount of light available in the scene, this loses a lot of the potency of the refractive effects I'm looking for, especially in scenes with low light levels.  So my question is, how can I reduce the amount of fireflies while using Cycles' caustics without sacrificing the quality of the refractive effects?  Note: I am aware that Cycles' caustics will perform much better once Cycles has full support for bidirectional path-tracing, but it looks unlikely that that will become , unfortunately.


I am pretty new using WordPress and was asked to validate the number of items in the cart for an eCommerce site that lets you "make a pack" in which you have several steps, step 1 is a page in which you select the box, this doesn't need validation but the next 4 steps do, each step is a new page and each has a different amount of the item that you need to select, what I need is to either disable the hyperlink that says "Next step" until you select the correct amount of items for each step or just display a message when you click with the incorrect amount  Now my question is not code itself but where to put it in WordPress, I checked everything in the WordPress admin part of the site and on the hosting site but can't find where I am supposed to code the validation for each page.

Is there an easy to understand scheme to decide what kind of code belongs to a plugin or the theme’s functions.php?  There    and many  about that topic, mostly because there are some misconceptions about the inner workings of WordPress. I am asking for an answer based on facts, not on opinions.  It should explain how to handle these points (and probably more):   custom post types and taxonomies contact forms shortcodes custom widgets  SEO functions like custom meta elements theme switch   There are often pros and cons for both sides. Our most popular question  got a lot of code snippets as answers that are at least debatable. We need criteria a beginner can understand, maybe a check list – with reasons.  See also the related question by Chip Bennett on our meta site:   Related:


The only reason I still use W indows is to play this game. I tried before and couldnt get it to work on Ubuntu and I wonder if it is possible now.

Can .exe and .msi files (Windows software) be installed in Ubuntu?