Wifi Hot-spot not working on Ubuntu 18.04

When I create a new AP hot-spot, the devices that try to connect cannot login due authentication error.I'm connected via ethernet with static IP configuration.  I followed   These steps creates me a WPA network.  The Ubuntu installation is new and fully updated.


What's the meaning of "to be use to +verb +ing"?  My doubt is if it can be used as the present of "used to" (habit or state in present), if it means to be able to stand an uncorfortable situation, or if both ways are ok.  I'll give two examples so you can analise:   I'm use to going to the beach at weekends. (I have the habit of going to the beach at weekends) I'm use to going to the beach by bus.  (though they are always full and take so long to get there)   In which case(s) is the usage of the tense correct, 1, 2, or both?  Thanks


How to get accumulated render time of animation

When rendering an animation in the render window on the top right you can see the render time of the last frame. But where can I see the sum of the render times of all frames?


How can I execute script after entire webpage has loaded

I have a simply script. For example:  var rowCount = $('tr').length; document.write(rowCount);   I want to load this after entire webpage has loaded. How can I do?


According to the   Although some object to the inclusion of of in such phrases as all of the students and all of the contracts and prefer to omit it, the construction is entirely standard.  What are the reasons behind such objection? There must be some grammar involved: first the definite article the, and second both students/contracts are plural and countable. **** EDIT **** OED reads (here's the  for the website; if somebody needs to use the cdrom, PM me) : XII. Indicating a quality or other distinguishing mark by which a person or thing is characterized. (For OE. genitive; F. de; = genitive of quality or description.) b. qualified by all, indicating (temporary) condition:  1849 Thackeray Pendennis xvi, ‘Do you say so?’ Smirke said, all of a tremble  : A. adj. II. absol.  Followed by of: in sing. The entire amount, every part, the whole; in pl. Every individual, all the members or examples. (This const. is comparatively modern, and is probably due to form-assoc. with none of, some of, little of, much of, few of, many of.) Rare, exc. with pronouns, as all of it, of whom, of which, of them. Also, as much as, altogether, quite; for all of (cf. for prep. 26b) U.S., as far as concerns (a person or thing). [See pronominal examples under 2c.]


Why didn't Eru stop Melkor and Ungoliant from destroying the Two Trees?

It has always been a mystery to me as to why Eru didn't intervene to stop Melkor and Ungoliant from destroying the Two Trees.  I don't think it is plausible to say that he was not aware of what they were doing while they were doing it, that is to say that he could not see through the cloud of darkness that had been put up around the Two Trees while they were being destroyed. Moreover, as soon as he saw them approach the first tree he should have hit them both with huge bolts of lightning or some kind of power.  So, why didn't Eru stop Melkor and Ungoliant from destroying the Two Trees?  Was this ever discussed with Tolkien and did he offer an explanation for this?


Passing list to viewparams variables in GeoServer SQL views?

I have a sql view which take only one parameter, but this parameter is a list, and a need to know how can i pass this parameter in the url  Here is my sql view  SELECT * FROM shop WHERE id IN %list%   When I put the default value for %list% as (1, 2 ,3) as example, the layer preview works and show the shopa with the default ids,  but when I try this in the url  viewparams=list:(1,2,3)   does not work.   I already tried other things like   viewparams=list:"1,2,3"   but nothing works.  Does anyone know how to do this?


How do I write the symbol ≢ ("not equivalent to") in LaTeX? Is there a way to put a slash through \equiv? \notequiv doesn't exist.


#include <stdio.h>  struct temp{  char b1;   double a;   int f; }; int main() {   struct temp temp1;   int size = 0;    size = sizeof(temp1); }   why size value is 24 instead of 20?... In 32 bit machine.   Advance Thanks...


Recurrence relation for right-angled triangles stuck-together

Given the image:   and that $x_0 = 1, y_0=0$ and $\text{angles} \space θ_i , i = 1, 2, 3, · · ·$ can be arbitrarily picked.  How can I derive a recurrence relationship for $x_{n+1}$ and $x_n$?  I actually know what the relationship is, however, don't know how to derive it.  Although it is obvious to see that $x_0 = x_1$  so for $n = 0$  We have $x_{1} = x_{0}+0 $  The recurrence relations are  $x_{n+1}=x_n−y_ntan(θ_{n+1})$  and   $y_{n+1}=y_n+x_ntan(θ_{n+1})$ But I can't get the derivation.    I tried taking some arbitrary right angle triangle and constructing two vectors.  $\mathop r_{\sim}  = \langle x_n,y_n \rangle $  and a vector perpendicular to $\mathop r_\sim$, $\mathop d_{\sim} = \langle a,b\rangle$ such that  $\mathop r_{\sim} \cdot \mathop d_{\sim} = 0 $  Then we can let construct a unit vector for $\mathop d_\sim$ and eventually construct a line through a point?


Laurent Series of $f(z) = \sin {\frac{1}{z}}$ at $z=0$

I am attempting to find the Laurent expansion at $z=0$  for $$f(z) = \sin {\frac{1}{z}}$$ where $z$ is a complex number. I rewrote the function as $$f(z)=\frac{ e^{iz^{-1}} - e^{-iz^{-1}}}{2i}$$ $$=\frac{1}{2i} \sum_{n=0}^{\infty}[i^n-(-i)^n]\frac{z^{-n}}{n!} $$  What do I do next?


Let $x,y,z>0$ and $x+y+z=1$, then find the least value of ${{x}\over {2-x}}+{{y}\over {2-y}}+{{z}\over {2-z}}$

Let $x,y,z>0$ and $x+y+z=1$, then find the least value of  $${{x}\over {2-x}}+{{y}\over {2-y}}+{{z}\over {2-z}}$$  I tried various ways of rearranging and using AM > GM inequality. But I couldn't get it. I am not good at inequalities. Please help me.  I wrote $x$ as $1-(y+z)$ and I took $x+y$ as $a$ and the others as $b$ and $c$. And I am trying.


sed single qoutes, double qoutes, delimeters

I am confused a little bit. I would like to swap 2 directory in the apache2 config files with the sed program.  APACHE_CONF=/etc/apache2/apache2.conf FULL_DIR=/home/$USER/new DEFAULT_DIR=/var/www/html`   This works fine:  sudo sed -i.bak 's|'$DEFAULT_DIR'|'$FULL_DIR'|' "$APACHE_CONF"   These are not (these don't have error, just do nothing):  sudo sed -i.bak 's/"$DEFAULT_DIR"/"$FULL_DIR"/' "$APACHE_CONF" sudo sed -i.bak 's/\"$DEFAULT_DIR"/\"$FULL_DIR"/' "$APACHE_CONF"   Can anybody explain why don't these work and why does the first one work?


I have this problem: when I try to compile a diagram I get the following message:     I think the culprit is a tikzcd arrow in ell 1-1   But I have not problem when, in the tikzlibrary, I just use cd, matrix and backgrounds. The problem is when using babel and cd at the same time.  \documentclass{article} \usepackage{amsfonts,amssymb,amsmath,tikz} \usepackage[spanish]{babel} \usepackage[latin1]{inputenc} \usepackage[mathcal]{euscript}  \usetikzlibrary{babel,cd,matrix,backgrounds}  \begin{document} \begin{center}   \begin{tikzcd}     X\rar[mapsto]{T}&Y   \end{tikzcd} \end{center}  \end{document}


What is the difference in "Boot with BIOS" and "Boot with UEFI"

Now Windows 8 supports the UEFI bootloader and I have read that its different from the BIOS, but it's unclear to me after many searches on the Google.  Some points in mind are below:-   As we all know, BIOS is an important part of accessing boot options. So UEFI will do that now? How?   How would I know that I'm booting with UEFI not with BIOS?  So what is the real difference in the "boot with BIOS" and "boot with UEFI"?


Sql combining two column into one variable

I have a sql command  SELECT A.*,        K1.AD CONTACTAD,        K1.SYD CONTACTSYD,        KR.AD KURUM,        K2.AD SUPERVISORAD,        K2.SYD  SUPERVISORSOYAD,        K3.AD REQUIRERAD,        K3.SYD REQUIRERSOYAD FROM          TD_ACTIVITY A,        KK_KS K1,        KK_KS K2,        KK_KS K3,        KK_KR KR WHERE  A.INS_CONTACT_PERSON = K1.ID    AND A.SUPERVISOR =  K2.ID    AND A.REQUIRERID = K3.ID     AND A.INSTITUTIONID = KR.ID   I want to combine CONTACTAD and CONTACTSOYAD into one variable like CONTACT.How can i do that?


Why the integral converges only when C is 1 and why other values of C would give infinity?

Find the value of the constant $C$ for which the following integral converges and evaluate the integral for this value of $C$   $$\int_{1}^{\infty}\left[\frac{C}{x+2} - \frac{1}{\sqrt{x^2 +4}} \right]dx  = \lim_{t\rightarrow\infty}\int_{1}^{t}\left[\frac{C}{x+2} - \frac{1}{\sqrt{x^2 +4}} \right]dx = \lim_{t\rightarrow\infty} \left(\sinh^{-1}(\frac{t}{2}) - C\ln(t+2)- \text{constant}\right)$$  By taking $\ln(t+2)$ common factor $$ \lim_{t\rightarrow\infty} \ln(t+2)\left(\frac{\sinh^{-1}(\frac{t}{2})}{\ln(t+2)} - C\right)- \text{constant}$$  $$ \text{Since} \lim_{t\rightarrow\infty} \frac{\sinh^{-1}(\frac{t}{2})}{\ln(t+2)} = 1 \text{    then C has to be equal 1} $$   and this is where I am confused $$ \lim_{t\rightarrow\infty} \ln(t+2) = \infty $$  and when we multiply this by $0$, we get undefined, so why should the $C$ be $1$. It is stated that if $C$ was anything but $1$ the answer would be  $\infty$


Column in where clause is ambiguous - What does that mean?

I've come across this error in MySQL for the join clause but I'm fairly new to the JOIN argument and I'm not sure what this means. Can anyone help?     Column 'id' in where clause is ambiguous   SELECT * FROM (`venues`)  JOIN `venues_meta` ON `venues_meta`.`venue_id` = `venues`.`id`  WHERE `id` = '12'


Is there a max array length limit in C++?

Is there a max length for an array in C++?  Is it a C++ limit or does it depend on my machine? Is it tweakable? Does it depend on the type the array is made of?  Can I break that limit somehow or do I have to search for a better way of storing information? And what should be the simplest way?  What I have to do is storing long long int on an array, I'm working in a Linux environment. My question is: what do I have to do if I need to store an array of N long long integers with N > 10 digits?  I need this because I'm writing some cryptographic algorithm (as for example the p-Pollard) for school, and hit this wall of integers and length of arrays representation.


Who is exempt from obtaining a Schengen visa?

I am British, my husband is from El salvador. We want to visit frankfurt, madrid., crete and italy for a few days only before going to UK . Do we need any visas like a tourist visa or a schengen visa?


How do DNA-binding proteins recognize the correct DNA base pairs?

My professor posed this question to the class today - "How do DNA binding proteins specifically bind to base pairs?"  He alluded to the different arrangements of hydrogen-bond donor and acceptors in A-T, T-A, C-G, and G-C base pairs. However, they are not always significantly different in some pairs (i.e. the minor groove of the C-G and G-C base pairs have the same acceptor - donor - acceptor pattern).  So how would a binding protein know the difference between C-G and G-C on the minor groove of a DNA base pair? How does a DNA binding protein know it's reached the right base pair, more generally?  Thank you!


How to ignore everything in the document environment?

Yes, you did read the title correctly!   I want to ignore everything that is between \begin{document} and \end{document} when I \input a file.  I thought that that would be very simple, just use :  \RenewEnviron{document}{}   But it turn out not be that easy. The MWE below yields the correct results:    but only with the comments intact. If you un-comment the commented lines then end up with:     LaTeX Error: \env@document@save@env undefined   Interestingly, ignoring this error one can continue past this, and still get the correct results. :-)  Notes:   I realize that in there can be other things in the preamble, so this is by no means a general solution. For the places where I need this functionality, the preamble only has \documentclass and two \input/\usepackage which loads all the .sty files needed so this will suffice for my needs.   Code:  \documentclass{article} \usepackage{environ} \usepackage{standalone}  \newtoks{\MyToken}  \usepackage{filecontents} \begin{filecontents*}{foo.tex}     \documentclass{standalone}     \usepackage{MyStandardPackages}      \MyToken={foo}  %   \begin{document} %       lots of text here % %       \SetSomeVarable{\SomeVar}{Some Value} %        %       \begin{SomeEnvironment} %           lots more stuff here as well %       \end{SomeEnvironment} %   \end{document} \end{filecontents*}  \MyToken={XXX}   \newcommand{\DisablePreamble}{%     \renewcommand{\documentclass}[2][]{}%  remove def'n of \documentclass     \renewcommand{\usepackage}[2][]{}%     ignore any \usepackage{} %   \RenewEnviron{document}{}% Ignore everything within the "document" environment. }%  \newcommand*{\ExtractMyToken}[1]{%     \begingroup% What happens in the group stays in the group!         \DisablePreamble%         \input{#1}%         \global\MyToken=\expandafter{\the\MyToken}%     \endgroup% }%  \begin{document} MyToken=\the\MyToken  \ExtractMyToken{foo}  MyToken=\the\MyToken \end{document}


Does the $\sum^{\infty}_{j=1}(b_j)^3$ converge if $\sum^{\infty}_{j=1}(b_j)$ converges?

If a series converges does the third power of the series converge? I want to say that if the terms of the series are all >0 then it does but if the series terms can be positive or negative I am not sure.


Is there a button in QGIS that will allow me to create parallel lines?  I do not mean by using a script, or distance from.   I usually use ArcMap, and in ArcMap you just begin editing, select parallel lines, and click on the line you want to parallel from.  There is also a perpendicular and right angle option. I use these a lot at work to create "perfect" lines around buildings.  Can you do this in QGIS, and if so how do you do it?  The question, "Creating parallel lines at particular distance from lines which are part of a shapefile," does not answer my question. I do not want to do distance from.  In fact I do not want to parallel form line features.  I want to parallel form polygon Features.  Say I am drawing a square with a polygon, I want to be able to make the first line of the square, then right angle from that line, and then right angle until I complete the square.  (Making a perfect square)    Now that I have made a square around a building, I need to draw the boundary of the site.    So I would start by paralleling off of the building lines.    I do this at work on ArcMap all day.  It creates beautiful maps for my clients.  I am trying to find out if I can do this on QGIS.    Again, this is editing polygons, not lines. In ArcMap this editing tool is a toolbar called ****Feature Construction****


induction proof on bezout's identity $d=ax+by$

I am reading the proof of the following theorem from Apostol's Introduction to Analytic Number Theory.  Theorem 1.2 Given any two integers a and b, there is a common divisor $d$ of a and b of the form $d=ax+by$, where $x$ and $y$ are integers. Moreover, every common divisor of $a$ and $b$ divides this $d$.  I'm stuck on the first step. The author used induction on $n$, where $n=a+b$ and assumed that the theorem has been proved for $0,1,2, \cdots, n-1$. I think the induction on $n$ should be an independent process where $n$ should be independent on other variables such as $a$ and $b$ here. For example, when we prove that binomial theorem: $$(x+y)^n=\sum_{k=0}^n\binom{n}{k}x^{n-k}y^k=\sum_{k=0}^n\binom{n}{k}x^ky^{n-k}$$ We would use the induction on $n$, and assume this equality holds for $0,1,2, \cdots, n-1$. However, $a,b$ are all constants, not relevant to $n$. What's wrong with my thought? For reference, the following is the whole proof from the book:  Here is a possible relevant: .


Avoiding \bibentry to be shown in regular \bibliography, using natbib

In an earlier question -  - I was looking for a possibility to have \bibitems appear in in my documents body. This was solved using the bibentry package.  As a follow-up I would now like to have the \bibitem appear in the body only, and not in the regular reference list in the end at all.  Is it possible to define something like a \bibentry* that prevents the entry from being shown? Or any other way to get what I want? I cannot get around using natbib...


Macro: Replace all occurrences of a word

I repeatedly use certain keywords such as var in my document which I highlight using \src{var}. This is cumbersome to type and gets annoying after a while. Repeatedly search-and-replacing var to \src{var} and then \src{\src{var}} to \src{var} also seems needlessly complicated. I want to tell LaTeX to replace all occurrences of var with \src{var}. I found \def that reduces the typing to \var{}, which is not much better. Something similar to the C preprocessor maybe: #define var \src{var}. I found the ""-example but failed to modify it to "Replacing all the vars". Thanks for the help.


I have created an extended event as below. I want to know how to query the historical data using T-SQL to see the issues at particular timestamps. The trace is running as of now  CREATE EVENT SESSION [PerQuerymonitor] ON SERVER  ADD EVENT sqlos.wait_info(     ACTION(sqlserver.database_name,sqlserver.plan_handle,sqlserver.sql_text)), ADD EVENT sqlos.wait_info_external(     ACTION(sqlserver.database_name,sqlserver.plan_handle,sqlserver.sql_text)), ADD EVENT sqlserver.disk_log_read(     ACTION(sqlserver.database_name,sqlserver.plan_handle,sqlserver.sql_text)), ADD EVENT sqlserver.sql_batch_completed(SET collect_batch_text=(1)     ACTION(sqlserver.database_name,sqlserver.plan_handle,sqlserver.sql_text)), ADD EVENT sqlserver.sql_batch_starting(     ACTION(sqlserver.database_name,sqlserver.plan_handle,sqlserver.sql_text)), ADD EVENT sqlserver.sql_statement_completed(     ACTION(sqlserver.database_name,sqlserver.plan_handle,sqlserver.sql_text)), ADD EVENT sqlserver.sql_statement_starting(     ACTION(sqlserver.database_name,sqlserver.plan_handle,sqlserver.sql_text))  ADD TARGET package0.event_file (SET filename=N'C:\SQLDatabase\PerQuerymonitor.xel', max_file_size=(204800)) WITH (MAX_MEMORY=4096 KB, EVENT_RETENTION_MODE=ALLOW_SINGLE_EVENT_LOSS,MAX_DISPATCH_LATENCY=30 SECONDS,MAX_EVENT_SIZE=0 KB,MEMORY_PARTITION_MODE=NONE,TRACK_CAUSALITY=OFF,STARTUP_STATE=ON) GO   Appreciate your kind help.


Why is my Singlton constant not staying constant

I am trying to create a singleton module that can store data.  I want to be able to edit this date only with setters or public functions and only access it with getters.  I was able to create a getter, setter and a set function.  However, I ran into a problem I cant explain when I tried to create a reset function.  I store my default settings in const _defPorts.  I then assign let _myPorts = _defPorts.  (I want to create a private variable _myPorts that is initialised with the constant values from _defPorts.  The problem is when I start setting new values, which I expect will only alter _myPorts, it seems to also change my _defPorts values.  I don't understand what I am doing wrong or how it is possible that my const value is being changed.  Because of this the reset function does not work.  In my console.log I am only displaying the value of _defPorts to show at which point it changes value.  I feel my problem is with the setPorts function but I do not know how to fix it.  Any help or advice would be greatly appreciated! :)  This is the Singleton Module I am trying to create:  'use strict' let activeConfig = (function () {   const _defPorts = {     http: 80,     https: 443,     secure: false   }    let _myPorts = _defPorts    let setPorts = function (value) {     console.log('SP->', _defPorts)     if (value) {       Object.keys(value).forEach((key) => {         if (typeof _myPorts[key] !== 'undefined') {           _myPorts[key] = value[key]         }       })     }   }    return {     setPorts: setPorts,     resetConfig: function () {       console.log('RC->', _defPorts)       _myPorts = _defPorts     },     get instance() {       console.log('GI->', _defPorts)       return this     },     get ports() {       console.log('GP->', _defPorts)       return _myPorts     },     set ports(value) {       return setPorts(value)     }   } })() module.exports = activeConfig   This is the code I am testing it with:  'use strict' const {   ports,   instance: activeConfig } = require('./activeConfig/activeConfig')  console.log('1 ->', activeConfig) console.log('2 ->', activeConfig.ports)  activeConfig   .setPorts({     secure: true,     http: 8080   })  console.log('3 ->', ports)  activeConfig.ports = {   secure: true,   https: 4444 }  console.log('4 ->', ports) console.log('RESET') activeConfig.resetConfig() console.log('5 ->', activeConfig.ports)   This is the console log output:  GP-> { http: 80, https: 443, secure: false } GI-> { http: 80, https: 443, secure: false } 1 -> {   setPorts: [Function: setPorts],   resetConfig: [Function: resetConfig],   instance: [Getter],   ports: [Getter/Setter] } GP-> { http: 80, https: 443, secure: false } 2 -> { http: 80, https: 443, secure: false } SP-> { http: 80, https: 443, secure: false } 3 -> { http: 8080, https: 443, secure: true } SP-> { http: 8080, https: 443, secure: true } 4 -> { http: 8080, https: 4444, secure: true } RESET RC-> { http: 8080, https: 4444, secure: true } GP-> { http: 8080, https: 4444, secure: true } 5 -> { http: 8080, https: 4444, secure: true }


How do I get rid of stale uninstalled entries in dpkg?

I see stale previously uninstalled packages in dpkg:  $ sudo dpkg -l *boost* Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad) ||/ Name                      Version           Architecture       +++-=========================-=================-================= un  libboost1.42-dev          <none>            <none>   However, I cannot remove the entry.  $ sudo apt --purge remove libboost1.42-dev Reading package lists... Done Building dependency tree        Reading state information... Done Package 'libboost1.42-dev' is not installed, so not removed  $ sudo dpkg --purge libboost1.42-dev dpkg: warning: ignoring request to remove libboost1.42-dev which isn't installed   Running apt-cache shows:  $ sudo apt-cache policy libboost1.42-dev libboost1.42-dev:   Installed: (none)   Candidate: (none)   Version table:


Dynamically added INPUT won't bind with event handler and trigger

The first DIV works, but then when new DIV rows are added, they don't get triggered. I suspect this has to do with event handler not binding with dynamically added elements, but how should I fix this, Thanks!:        // This adds more Education input     $(document).ready(function(){          $("#addLanguage").click(function(){             $("#LanguagesSection").append("
LANGUAGE: <input name=\"Languages[]\">SPEAK <input type=\"checkbox\" class=\"LanguageLevel\" name=\"LSpeak[]\" value=\"Speak\"> READ <input type=\"checkbox\" class=\"LanguageLevel\" name=\"LRead[]\" value=\"Read\"> WRITE <input type=\"checkbox\" class=\"LanguageLevel\" name=\"LWrite[]\" value=\"Write\"> FLUENT <input type=\"checkbox\" class=\"LanguageLevel\" name=\"LFluent[]\" value=\"Fluent\"><input name=\"LanguageLevels\" class=\"LanguageLevels\" size=\"37\" placeholder=\"<--Please Choose one of the four\" readonly value=\"level: \">Remove
");         });                  $("#LanguagesSection").on("click", ".removeLanguage", function(e){             e.preventDefault();             $(this).parent().remove();         });                   // Work in Metro Area Checkboxes         $("input.LanguageLevel").on('change', function() {             var $row = $(this).closest('.LanguagesTable');             var $input = $('.LanguageLevels', $row);             $input.val(this.value + " " + this.checked);          });     });

     LANGUAGE: <input name="Languages[]"> SPEAK <input type="checkbox" class="LanguageLevel" name="LSpeak[]" value="Speak"> READ <input type="checkbox" class="LanguageLevel" name="LRead[]" value="Read"> WRITE <input type="checkbox" class="LanguageLevel" name="LWrite[]" value="Write"> FLUENT <input type="checkbox" class="LanguageLevel" name="LFluent[]" value="Fluent">         <input name="LanguageLevels" class="LanguageLevels" size="37" placeholder="<--Please Choose one of the four" readonly value="level: ">

 <input type="button" id="addLanguage" value="Add Language">


Dictionary search engine by pronunciation

I'm looking for some word search engine that would allow me to search words by their pronunciation. For instance, I want a list of words beginning with "ge", but pronounced as in "get" and ignoring ones like  "Germany" or "gear".


I have a problem with Eclipse, it crash every time I try to commit, or to view the project settings and I discover  that the problem is for oxygen-gtk.  Is recommended to downgrade it. But how to? I have kubuntu 14.04.  Thanks.


Exact number of times a question is viewed?

Is it possible to determine exactly how many times a question has been viewed on any Stack Exchange network site?  After a page has been viewed for around a thousand times, all I get to see is view count rounded to the nearest thousand (or million).  Is there a way to get an exact count of how many times a question has been viewed?


Color entire row based on the status in Column L

How can I make my spreadsheet look like in the picture below? Starting row 5, I want to color the entire row based on the status in Column L.


How do I make a bootable USB OS X installer on a Mac?

Does anyone have a Terminal command-line recipe for making a new bootable USB flash drive for one of the new MacBook Air's?  Is there a way to dd copy the USB boot device that comes in the box and make the new copy bootable?  I'd like to make a new backup copy of the USB rescue device for my MBA, preferably on a much larger flash drive with room for a backup of some of my working directories.  Added:  And is it possible to make, not just a rescue drive, but a bootable USB drive that will boot a fully updated version of the OS (say 10.6.8 or later)?  If so how on a MacBook Air 11, and how big a USB stick will this require?


how to Skip unauthorized access directory and moving to next directory to search all the".txt"?

I am trying to search all ".txt" file for a drive (C:). For that I am searching "AllDirectories" of drive C:, but I am getting exception while some directory access is denied and my program terminates.   try             {                 var filename = Directory.GetFiles("C:\\", "*.txt", SearchOption.AllDirectories);                 Console.WriteLine(filename.ToString());                 foreach (string a in filename)                 {                      Console.WriteLine(a);                 }             }             catch (Exception ex) { Console.WriteLine(ex); }   System.UnauthorizedAccessException: Access to the path 'C:\Documents and Settings' is denied.  How to skip unauthorized access directory and moving to next directory to search all the".txt"?  Exception:  System.UnauthorizedAccessException: Access to the path 'C:\Documents and Settings' is denied.    at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)    at System.IO.FileSystemEnumerableIterator1.HandleError(Int32 hr, String path)    at System.IO.FileSystemEnumerableIterator1.AddSearchableDirsToStack(SearchData localSearchData)    at System.IO.FileSystemEnumerableIterator1.MoveNext()    at System.Collections.Generic.List1..ctor(IEnumerable`1 collection)    at System.IO.Directory.InternalGetFileDirectoryNames(String path, String userPathOriginal, String searchPattern, Boolean includeFiles, Boolean includeDirs, SearchOption searchOption, Boolean checkHost)    at System.IO.Directory.InternalGetFiles(String path, String searchPattern, SearchOption searchOption)    at System.IO.Directory.GetFiles(String path, String searchPattern, SearchOption searchOption)    at ConsoleApp1.Program.Main(String[] args) in c:\users\h190733\source\repos\ConsoleApp1\ConsoleApp1\Program.cs:line 16


How much is the normal salary of a postdoctoral fellow in North America and Western Europe?

I understand that the salary of a postdoctoral fellow depends on the field, project, contract, and so forth, but I am curious how much is the normal range for a fellow. Someone told me that he prefer to continue postdoctoral fellowship, as he gets the same salary of assistant professorship with less official duties.  In my experience, the range of salary for a postdoctoral fellow is much less than an assistant professor, something between $25,000 - $50,000. In Europe, it is in the lower side, but it is usually higher in the US.  I am curious to know what is the actual rate, and is there a norm for estimating the salary of a postdoctoral fellow?  In other words, when looking at postdoctoral openings, how much is an excellent/good/normal deal?


proof that p-value is uniformly distributed when the null hypothesis is true

this is a follow up to the following response:   the response makes sense if $P=F(T)$ but what if the hypothesis you're testing requires $P$ to be calculated differently for example $P=1-F(T)$ ?


Prove that $\nu(n) \le \nu(2^{n}-1)$ where $\nu(n)$ is the number of positive divisors of n

Prove that $\nu(n) \le \nu(2^{n}-1)$  Ok so I have very few ideas for this question. I thought if I could find the prime decomposition of $2^{n}-1$, I could go somewhere with the formula for $\nu$, but I've had little success. Any help would be much appreciated.


When developing WPF UserControls, what is the best way to expose a DependencyProperty of a child control as a DependencyProperty of the UserControl?  The following example shows how I would currently expose the Text property of a TextBox inside a UserControl. Surely there is a better / simpler way to accomplish this?     <UserControl x:Class="WpfApplication3.UserControl1"         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">         <StackPanel Background="LightCyan">             <TextBox Margin="8" Text="{Binding Text, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type UserControl}}}" />         </StackPanel>     </UserControl>      using System;     using System.Windows;     using System.Windows.Controls;          namespace WpfApplication3     {         public partial class UserControl1 : UserControl         {             public static DependencyProperty TextProperty = DependencyProperty.Register("Text", typeof(string), typeof(UserControl1), new PropertyMetadata(null));             public string Text             {                 get { return GetValue(TextProperty) as string; }                 set { SetValue(TextProperty, value); }             }                  public UserControl1() { InitializeComponent(); }         }     }


I've been wondering, what is the point of clog? As near as I can tell, clog is the same as cerr but with buffering so it is more efficient. Usually stderr is the same as stdout, so clog is the same as cout. This seems pretty lame to me, so I figure I must be misunderstanding it. If I have log messages going out to the same place I have error messages going out to (perhaps something in /var/log/messages), then I probably am not writing too much out (so there isn't much lost by using non-buffered cerr). In my experience, I want my log messages up to date (not buffered) so I can help find a crash (so I don't want to be using the buffered clog). Apparently I should always be using cerr.  I'd like to be able to redirect clog inside my program. It would be useful to redirect cerr so that when I call a library routine I can control where cerr and clog go to. Can some compilers support this? I just checked DJGPP and stdout is defined as the address of a FILE struct, so it is illegal to do something like "stdout = freopen(...)".   Is it possible to redirect clog, cerr, cout, stdin, stdout, and/or stderr? Is the only difference between clog and cerr the buffering? How should I implement (or find) a more robust logging facility (links please)?


How do you get JavaScript/jQuery Intellisense Working in Visual Studio 2008?

I thought jQuery Intellisense was supposed to be improved with SP1. I even downloaded an annotated version of jQuery 1.2.6, but intellisense will not work in a separate jscript file. I have the jQuery library referenced first on my web page in the <head> tag. Am I doing anything wrong?


Deriving Conservation of Angular Momentum from Newton's Laws

Given that a collection of classical particles can be modelled using Newton's three laws, it must be the case that both the conservation of momentum and the conservation of angular momentum are emergent features of Newton's three laws.  I can easily show the conservation of linear momentum from the third law, but how can the conservation of angular momentum be derived from Newton's three laws?


How can you try to spawn a pre-tamed cat with or without commands?

I want to spawn a pre-tamed black cat and name it "Suki I" and have a black baby cat named "Suki II". How do you do said action without spawn eggs?


Let $A$ and $B$ be two subgroups of the same group $G$. What does it mean for the subgroup $A$ to be normalized by the subgroup $B$?


What is the computational complexity for regular languages?

Is it the case that set membership problem for all regular languages can be solved in the time complexity of order $O(n)$ ? And Can we say that all set membership problems that can be solved in $O(n)$ are regular, where n is the input set?   My approach: We can construct a DFA for the regular language, then in that case the time complexity will be of order $O(n)$, but it does not prove that all set membership problems that run in $O(n)$ will be regular so how should we proceed with this part of the proof.


Uploading shapefile onto Garmin GPS, and displaying it over basemap?

I have a roads shapefile layer in ArcMap and I want to be able to view it on my Garmin64st. Ideally, it would be overlaid on a basemap so I would always be able to see it. It seems like that means I need to convert my .shp file to .img.   I'm finding various programs that claim to help with some step of this, but some of them are really expensive, and none of the free ones I've tried have gotten me to .img so far. I did download an ArcGIS Toolbox which converts .shp to .gpx, but I haven't been able to find a way to convert that to .img for free yet.   Am I missing something?   Does anyone know a simple and free way to convert a .shp to be viewed in a Garmin GPS like I've described?   If I absolutely must purchase a program, do you know of one that works?


Recently I've come across this sentence in Keynote Advanced:  Over 50 per cent of our materials come / comes from local suppliers.  The answer provided in the teacher's book is comes. I've checked several grammar textbooks and all of them say that it should be come. For example, here is an excerpt from Advanced Grammar in Use by Martin Hewgings:  When the first noun in a complex subject is a percentage or a fraction the verb agrees with the nouns closest to the verb. E.g. About 50% of the houses need major repairs.  I'm inclined to think that comes in the answer key is a typo, but maybe I'm missing something. Could you please advise?


Is the concatenation of all prime numbers, a universe/disjunctive number?

A universe number is a number which contain any finite length string of digits for a base.   Reference . These are usually called "disjunctive numbers" in English.  Then the question is, is the concatenation of all prime numbers, a disjunctive number?  By the  we can find that $$\forall n \ge 6,\text{ }\ln(n)+\ln\left(\ln(n)\right)-1<\frac{p_n}{n}<\ln(n)+\ln\left(\ln(n)\right)$$ where $p_n$ is the n-th number prime.  But I don't know what to do after. Any hint would be appreciated.


Should I add a tag to a question after the answer indicates that something, identified by the tag, is related with the question?

For example, if someone asks this question:     I'm getting an error doing X. Why?   A possible answer could be:     You need to do Y to avoid getting this error.    If Y is a technique or tool and if Y has a tag, should I edit the question to add the  tag? It seems correct because specialists in  will be able to find the question and add more useful information.  However, I can see two issues:   If  or  is also a possible solution, the question will have many distinct tags.   Example  Question:     My PC is freezing. What should I do?   Answer 1:     You need to run an anti-virus to remove malwares.   Answer 2:     Your PC may be overheated. Check if your fan is working correctly.   So, in this case, should I add  +  to the question?     If the question is marked with , the OP will look a bit dumb for asking something that is quite obvious if you see the tag.   Example  Question:     What series is it?   Answer:     This is "Game of Thrones".   Adding a  tag would make the OP to look dumb.  Another example for this would be:  Question:     How can I securely store an user password?   Answer:     You should hash the password before storing it.   In this case, should I add the  tag?     So, how should I proceed? Is there a generic guidance?


Word that means "the opposite of what you would expect"

I'm looking for a word that means the opposite of what one would expect. This word might be used to express the surprise that a teenager's grandmother uses text messaging much more than he does, or that a city seems brighter at night than it does during the day.   I'm not seeking the word ironic or irony which refer to the use of something to describe its opposite experience or emotion.


Prove $\lfloor 2x \rfloor + \lfloor 2y \rfloor \geq \lfloor x \rfloor + \lfloor y\rfloor+\lfloor x+y\rfloor$

Prove that $\lfloor 2x \rfloor + \lfloor 2y \rfloor \geq \lfloor x \rfloor + \lfloor y \rfloor + \lfloor x+y \rfloor$ for all real $x$ and $y$.   If anybody could post a simple solution (no complicated abstract theories or calc :D) to the above question, I would greatly appreciate it. Thanks!  Also, if possible, the solution shouldn't wander too much away from floor, ceiling, fraction functions, and other related functions.


How do I delete a folder or an album from Photos?  Have searched internet for answer and tried using control, option and command keys.


Clarification on circular motion and pseudo-forces

The way i interpret pseudo-forces is that its a mathematical correction that makes the conclusion of the observer in an accelerated frame correct.  And I also believe that this "pseudo-force" has no physical significance, that is, it isn't something actually acting on the body being observed.  While doing circular motion problems, while analyzing from the rotating frame, we add a pseudo-force in the outward direction.  Now, we *actually do feel an outward force * when we are in circular motion, (like when we are taking a turn on the road) and I have seen many textbooks attributing this to the "centrifugal force", which I believed to be simply a pseudo-force and thus, is not something that is physically affecting a body.  What is the correct explanation to this problem?  edit: I think I somewhat got the idea, but I still don't feel I can generalize it to other situations, like:  1)A liquid in a rotating tube (in a horizontal plane) moves Outwards  2)Suppose a block is kept on a rough rotating table,(the block also rotates).We say that friction provides the centripetal force. But say the angular speed is such that friction becomes insufficient to provide the force, and the block moves outwards. Also, from an inertial frame, if friction is acting towards the center, it means the body has a tendency to move away from the center.  Can these two situations be explained by the same, inertia arguement?


I have Samsung Galaxy S7 and I want to check if I have a Snapdragon or Exynos chipset. I need this info because I plan to install Android Pie or 10 and I need to know exactly which chipset the phone has. My baseband is G930SKU3ETG1, Build number R16NWG930SKSU3ETG2, yet back casing SM-G930P. SNAPDROGON or EXYNOS? It has already been rooted with android 8.0.0. Can anyone help please?


I have a tmux session already running. I have created it just with  tmux   now I can leave the session and re-enter with  tmux a -t 0   how can I share this session with other users? Usually one has to create the session with -S option, but I haven't. Is there a way to share my session?


How to restrict access to a node via node/12 and allow access via a path like content/sometitle?

Problem: I want to restrict direct node access using node number www.example.com/node/12 and allow access using pathauto alias www.example.com/content/sometitle to anonymous user. This user should be allowed to see all content of node using only  title path but not with node number to snoof.  Mostly I want to target anonymous users. Admin always has access to everything.   In simple terms, I want to redirect all node/Number paths (not node/add/ContentType) to say the Home page or No Access page.


What is potential value of an additional pointing domain?

We have an opportunity to buy an extra domain that is quite specific to what we do and where we do it e.g. newyorkplumber.com.   This domain will just point to our current business's website url which is our business's name : fooplumber.biz  Does this new domain have any chance of showing up on search results if someone searches for "New York plumber"?  Is it worth while to buy additional pointing / forwarding domains if they are very specific to our business i.e. does it have potential to bring us any additional traffic?


So, is getting a new(past) Tony Stark the most dangerous thing they could ever do?

This kind of confuses me... Taking a stone from a timeline disrupts the said timeline right? While getting a person FROM a timeline seems no repercusion (E.G Loki vanishes with the Tesseract(Space stone), 2014 Thanos comes to present)   Why can't they just get a Tony Stark from the past, maybe before the snap? Or maybe alter the whole History (Make Captain Marvel snap the gauntlet rather than Tony, she held the gauntlet for some time right?)  Just so that Stark can have his family and the whole movie wont have to have a sad ending.


how to add an event to element when using template tag with Javascript

I want to add an event to an element using addEventlistener this is my code : for(let i = 0 ;i < dataArrays.length ; i++){         let template = document.getElementsByTagName("template")[0] ;          template.content.querySelector(".add-button").firstElementChild.setAttribute("src",dataArrays[i].addButtonImage) ;         let clon = template.content.cloneNode(true);         document.querySelector(".produnt-list").appendChild(clon);     }  I used codes blew to do this but it is not working at all ... template.content.querySelector(".add-button").addEventListener("click",function(){             console.log("Hello World !");         })


Minecraft command blocks, how do I detect a block on the ground, for example stone

I just can’t find anyway to do it I’ve already tired so many commands but they are all just old or outdated. If anyone could help me that would be great


Trackpad not working after update to Ubuntu 14.10 on Dell Inspiron 15R

When I updated from 14.04 to 14.10 I noticed my track-pad cursor and left and right mouse clickers were not working. I have tried looking this issue up and can not find any solutions anywhere. If anyone could help me that would be amazing, I am using a wired mouse to my USB port for a temporary fix. I have a Dell Inspiron 15R.


restore a smaller hard drive 320GB image to a larger harddrive 1TB

I want to transfer my current system hard drive to a larger hard drive. Doing so, I thought of creating an image of my system hard drive which is 320 GB in size.   Would I be able to restore this image on a larger hard drive? I plan buying a 1TB hard drive.  If yes, how? I prefer no data loss.  I am using Windows 7


When there are several cottages each with several tariffs (depending on the season), should the plural be "cottage tariffs" or "cottages tariffs"?  For context, this is to be a section title on a website renting out the cottages.  An explanation of the grammatical rules would be helpful.


I have played the Witcher 3, exchanged dialogue with 5 trolls already, and decided not to kill them. All 5 trolls were involved in specific quests. I have killed two trolls of which I did not exchange dialogue. I have yet to receive a Troll Mutagen.  How does one obtain a Witcher 3 Troll Mutagen from a non-quest specific troll, at least one of which you never exchange dialogue with?


Can't launch graphical apps from terminal after updating to 15.10

After updating to 15.10 it's impossible to run graphical apps from terminal:  xxx@xxx:~$ gksudo wireshark Invalid MIT-MAGIC-COOKIE-1 key (gksudo:5532): Gtk-WARNING **: cannot open display: :0 xxx@xxx:~$ sudo -H wireshark [sudo] password for xxx:  Invalid MIT-MAGIC-COOKIE-1 key ** (wireshark:5535): WARNING **: Could not open X display Invalid MIT-MAGIC-COOKIE-1 keyFailed to connect to Mir: Failed to connect to server socket: No such file or directory Unable to init server: Could not connect: Connection refused  (wireshark:5535): Gtk-WARNING **: cannot open display: :0 xxx@xxx:~$ wireshark Invalid MIT-MAGIC-COOKIE-1 key ** (wireshark:5569): WARNING **: Could not open X display Invalid MIT-MAGIC-COOKIE-1 keyFailed to connect to Mir: Failed to connect to server socket: No such file or directory Unable to init server: Could not connect: Connection refused  (wireshark:5569): Gtk-WARNING **: cannot open display: :0 xxx@xxx:~$ gedit Invalid MIT-MAGIC-COOKIE-1 key ** (gedit:5570): WARNING **: Could not open X display Invalid MIT-MAGIC-COOKIE-1 keyFailed to connect to Mir: Failed to connect to server socket: No such file or directory Unable to init server: Could not connect: Connection refused  (gedit:5570): Gtk-WARNING **: cannot open display: :0 xxx@xxx:~$ sudo gedit Invalid MIT-MAGIC-COOKIE-1 key ** (gedit:5574): WARNING **: Could not open X display Invalid MIT-MAGIC-COOKIE-1 keyFailed to connect to Mir: Failed to connect to server socket: No such file or directory Unable to init server: Could not connect: Connection refused  (gedit:5574): Gtk-WARNING **: cannot open display: :0   My little research pointed to gksudo using but it ain't working either. I've also tried some stuff with xauth. What is the problem? Thanks.


Does a sorcerer's metamagic work for non-sorcerer spells?

Can a multiclass sorcerer/cleric use the Metamagic class ability with non-sorcerer spells? For example, using Twinned Spell when casting cure wounds to heal two creatures instead of just one?


Proving that a normal, abelian subgroup of G is in the center of G if |G/N| and |Aut(N)| are relatively prime.

I was trying to prove that a normal, abelian subgroup of $G$, $N$ is in the center of $G$ given that $|\operatorname{Aut}(N)|$ and $|G/N|$ are relatively prime.   The official question:     Let $N$ be an abelian normal subgroup of a finite group $G$. Assume  that the orders $|G/N|$ and $|\operatorname{Aut}(N)|$ are relatively prime. Prove that $N$ is contained in the center of $G$.   My approach:  I considered the homomorphism: $f:G \to \operatorname{Aut}(N)$ such that $f(g)(n) = gng^{-1}$. This was given as a hint on the problem. So naturally, the first this I did was compute the kernel, and found the kernel to be $N$ since any element in $N$ maps to the identity automorphism since $N$ is abelian.   But I don't know how to use the fact that $\gcd(|G/N|, |\operatorname{Aut}(N)|) = 1$ since it is not necessarily true that $G/N$ and $\operatorname{Aut}(N)$ each have prime order.   Am I missing some trivial property about the kernel of this homomorphism that would enable me to say something about $N$ and or its relationship with $Z(G)$?  Any help would be thoroughly appreciated.


It is given that $a_n>0$ and $\sum_{n=1}^{\infty}  a_n$ is divergent. Prove that there exists a decreasing sequence $b_n \rightarrow 0$ such that $\sum_{n=1}^{\infty} a_n b_n$ diverges.  I thought of an example: Let $b_1=1$ and $b_{n+1}=\min (1/(2^n a_{n+1}), b_n, 1/n)$ for $n \geq 1$. Will this work?


Find directories that don't have a file with specified name

I've done a good amount of research on this and put together this command, but it appears to be finding the directories that HAVE scanned.txt not the directories that don't have scanned.txt. How can I Modify this to fit my needs? find . -type f -maxdepth 2 -not -name 'scanned.txt' -exec dirname {} \; | sort -u >> NOT_SCANNED.txt  Thanks


Can someone give me an example of how to work out an exact linear second order differential equation?

I have a theorem that states:  If an equation $P(x)y''+Q(x)y'+R(x)y=0$  can be written in the form:  $$[P(x)y']'+[f(x)y]'=0$$  then the equation is said to be exact.   Now I need to expand and equate the coefficients of these equations to show that a necessary condition for an equation to be exact is...  $$P''(x)-Q'(x)+R(x)=0$$  I began to expand the second equation but I do not know where to go from there.


How to Delete All the Files in the Current Directory Except the Last Two

Let's say there are 10 files in this current directory /home/usr. They are numbered 1-10. If I wanted to delete all the files except 9 and 10, how would I go about it?   I can select the bottom two files by doing  ls -l /home/usr/ | tail -2   However, how would I use this information to remove all BUT the last two? In other words, how would I remove 1-8?  I am going to clarify some things. I would like to remove based on the listing of ls -l and not specifically by the name of the files. As in those 1-10 files were examples. It should remove files regardless of the specific names and remove the bottom two of ls -l.


resume reading a log file from the point I left it last time

I have a log file which is continuously updating(new line added) after few time period.  I am fetching only error messages from the file in every 10 minutes.  Initially, at 1st time I fetched all line into a new file with a matching pattern "ERROR FOUND" using awk.  But after 10 min more new line has been added to a log file, so I want to read that log file where I left. I don't want to start from the beginning again.  Can any body suggest me best code or script for this?


I was reading a  published on Dropout. What I find difficulty in understanding that, In the training phase, a unit is present with a probability p and not present with a probability 1-p. In the test phase, all units are present, but we multiply each of them with the probability.   Now, is it like, let we have 4 input units originally named a,b,c,d. In the training stage, after applying dropout, with a dropout rate of 0.5, we are left with units a and c. So, As in the test stage, all the units are present, so, is it like, we multiply each of the units with 0.5? Also, Is p defined for each of the units in the network, or for the entire Neural Network?  Also, In doing so, how is the result same for training and test stage?


A polynomial that is zero on an open set

Suppose that a polynomial $p(x,y)$ defined on $\mathbb{R}^2$ is identically zero on some open ball (in the Euclidean topology). How does one go about proving that this must be the zero polynomial?


Can I connect 2 external monitors to my 12" Retina MacBook (early-2015)?

Can I connect two external monitors to my 12" Retina MacBook (early-2015)  How do I do it and can it be VGA or only HDMI


How can I debug why Ubuntu boots to BusyBox?

When I turn my PC on, it asks me if I want to boot Ubuntu 16.04 or Windows 10. When I choose Ubuntu 16.04, it look like it is booting, but then it just show me this screen:  BusyBox v1.22.1 (Ubuntu 1:1.22.0-15ubuntu1) built-in shell (ash) Enter 'help' for a list of built-in commands  (initramfs)   I was installing Ubuntu by CD. First time, when was installation complete, the system was running without any problems, but when I turned my PC off (there wasn't any problems or messages during the shutdown) and then turned it on and choosed Ubuntu this happend.


Irreducible is prime in the ring $\mathbb{Z} + X\, \mathbb{Q}[X]$

If a ring is a UFD, its irreducible elements are exactly its prime elements.      Show that the reverse is not true. Give a nontrivial counterexample.      Hint: Consider the ring $\mathbb{Z} + X\, \mathbb{Q}[X]$.   Note: in the following solution "denominator" of a rational number always means the denominator of its fraction simplified to lowest terms.  Let $R:= \mathbb{Z} + X\, \mathbb{Q}[X]$, whose only units  are $R^\times = \{+1, -1\}$.   We show that if $a$ is reducible in $\mathbb{Q}[X]$, which means that $a = q r$ with $\deg(q), \deg(r) \ge 1$, then it is reducible in $R$.   \begin{equation*}    a(X) = \Bigl(\sum_{i=1}^{m} q_i X^i\Bigr) \cdot \Bigl(\sum_{j=1}^{n} r_j X^j\Bigr) \quad \text{with $m, n \ge 1$}\, .  \end{equation*}  Since $q_0 r_0 = a_0 \in \mathbb{Z}$, there is an $c \in\mathbb{Q}$ with $c q_0, \frac{r_0}{c} \in \mathbb{Z}$. To be more precise $c = \frac{\text{Denominator of $q_0$}}{\text{Denominator of $r_0$}}$.  Then \begin{equation*}   a(X) =  \Bigl(\sum_{i=1}^{m} c q_i X^i\Bigr) \cdot \Bigl(\sum_{j=1}^{n} \frac{r_j}{c} X^j\Bigr) \, , \end{equation*} so $q, r \in R$ and not units, so $a$ is reducible in $R$.  Let $a, b, p \in R$ with $p$ irreducible and $p \mid a b$. Now we look at the problem in $\mathbb{Q}[X]$. As shown, $p$ cannot be reducible $\mathbb{Q}[X]$, so it must be a unit or irreducible.  We first treat the case that it is irreducible in $\mathbb{Q}[X]$. Since we are now in an UFD if $p \mid a b$ it follows that $p \mid a$ or $p \mid b$.  Assume without loss of generality that $p \mid a$. So there is an $u\in\mathbb{Q}[X]$ with $p u =a$. It follows that $p_0 \cdot u_0 = a_0 \in \mathbb{Z}$. If $u_0 \not\in \mathbb{Z}$, there is $c \in \mathbb{Z}$ (the denominator of $u_0$) for which $\frac{p_0}{c}\in\mathbb{Z}$ and so $\frac{p}{c}\in R$, which contradicts the assumption that $p$ is irreducible in $R$. But if $u_0 \in \mathbb{Z}$, also $u\in R$ and we have in $R$ (!) that $p$ divides $a$.  Now we treat the case that $p$ is a unit in $\mathbb{Q}[X]$. Since $(\mathbb{Q}[X])^\times = \mathbb{Q}\setminus\{0\}$ and $R \cap \mathbb{Q} = \mathbb{Z}$, it follows that $p\in\mathbb{Z}$ and since $p$ is irreducible, it has to be a prime number. If $p\mid ab$, it follows that $p_0 \mid a_0 b_0$ (again with $a_0, b_0\in \mathbb{Z}$), so $p_0\mid a_0$ or $p_0\mid b_0$ and therefore $p \mid a$ or $p \mid b$.  We have proven that all irreducible elements of $R$ are prime.   But $R$ is not an UFD, for example  $$\frac{X^2}{6} = \frac{X}{2} \cdot \frac{X}{3} = \frac{X}{6}\cdot X \, .$$  Can somebody have a look if this solution is ok? I think the solution seems far too complicated. Either I've missed something obvious or there is a theorem which would make it much easier.  PS: What would be a trivial counterexample?


OK I understand the basics, but can someone explain code copied from Greg's answer :  a[1::-1]   # the first two items, reversed a[:-3:-1]  # the last two items a[-3::-1]  # everything except the last two items, reversed   To me the first one reads: slice from 2nd position to end, then reverse it.  The second one is slice from beginning to the -2 position then reverse it.  The third one is slice from -3rd position to end then reverse it.  Obviously I am wrong since they work as suggested, but can you please tell me why?


Good books and lecture notes about category theory.

What are the best books and lecture notes on category theory?


usefulness of k-means clustering on high dimensional data

I wonder what is the usefulness of k-means clustering in high dimensional spaces, and why it can be better (or not) than other clustering methods when dealing with high dimensional spaces.


Scale is not updated correctly when changing zoom on reputation graph

If I zoom somewhere on the reputation graph, the scale is not correctly updated:  Original unzoomed:   Zoomed (note that the vertical scale has not been correctly updated):   Reset zoom (the vertical scale is now completely wrong and even out of order; horizontal scale is not correctly updated either):   I can consistently reproduce this with Firefox 69.0 (64-bit) and with Chrome 77.0.3865.75 on Windows 7 and on Linux.


Creating sequential numbers in sorted field using ArcGIS Field Calculator?

I have a sorted field that I would like to populate with sequential numbers.  They are not in order of OID.   Is there any way to do this?


Do not allow bounties to be offered if there is a close review pending

We have  that (and why) it is impossible to cast close votes on bountied questions, and this is not about that, but a related issue:  It is possible to post a bounty while the post in question is currently pending review in the close review queue.  A pending review indicates that the question is potentially off-topic, and it is not readily apparent why we should allow bounties to be posted on such questions (while it is indeed clear that closing already bountied questions brings a host of issues related to refunding the bounty with it that only moderators can deal with, as has been discussed before).  Therefore, this is a feature request to disable the ability to bounty a question if the question is currently pending review in the close queue, i.e. if there are close votes cast on it that have not been countered by the required three leave open votes to take it out of the queue.    The  this has been closed as a duplicate of is very close to being a duplicate, but I linked the other question in my very first sentence. This isn't about casting votes on bountied questions, it's about bountying questions with close votes. My proposal is a bit narrower than that of the second question - "pending close review" is a weaker condition than "has close votes", but if you think that this difference is not sufficient to make a seperate feature request, so be it. (In that case, perhaps leave a comment on what I should do with this narrower proposal: Leave it as a comment on the other question? As an answer? Nothing?)


Let $(X,\|\cdot\|)$ be a Banach space and $(X^*,\|\cdot\|_{op})$ its continuous dual Banach space.   Let $\text{End}_{op}(X^*)$ be the continuous linear endomorphisms of $X^*$ with respect to $\|\cdot\|_{op}$ and $\text{End}_*(X^*)$ the continuous linear endomorphisms with respect to the weak-* topology of $X^*$.   Does $\text{End}_{op}(X^*)=\text{End}_*(X^*)$? If not when are they equal and how do they compare in general? Also references and proofs are welcome.


Why is the method executed last always faster?

I am learning about Binary Search Trees, and want to compare the performance of two insertion methods(basic concept is same but there is a little difference in implementation).   I stored time(in nanoseconds) before and after calling the methods and printed the difference. This way, the time required for executing the method called first is always more even when the sequence of calling the methods is reversed.    Common Code :-     BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); int[] terms = Arrays.stream(br.readLine().split("\\s+")).mapToInt(Integer::parseInt).toArray(); BST tree = new BST();   Procedure 1 :-  long t1 = System.nanoTime(); Arrays.stream(terms).forEach(tree::insert); long t2 = System.nanoTime(); tree = new BST(); long t3 = System.nanoTime(); Arrays.stream(terms).forEach(tree::insert1); long t4 = System.nanoTime(); System.out.println("insert ->" + (t2 - t1) + "\ninsert1->" + (t4 - t3));   Procedure 2 :-  long t1 = System.nanoTime(); Arrays.stream(terms).forEach(tree::insert1); long t2 = System.nanoTime(); tree = new BST(); long t3 = System.nanoTime(); Arrays.stream(terms).forEach(tree::insert); long t4 = System.nanoTime(); System.out.println("insert1->" + (t2 - t1) + "\ninsert ->" + (t4 - t3));   Input :- 12 23 34 45 56 67 78 89 90 Output Procedure 1 :- insert ->2155125 insert1->431351 Procedure 2 :- insert1->2608819 insert ->546649  How can I correct this problem?


CentOS7 Can't install VBoxGuestAdditions because kernel headers not found

I'm using VirtualBox Version 6.1.8 r137981 and trying to get full screen desktop working. I believe I need to install VBoxGuestAdditions. I have Oracle VM VirtualBox Extenstion Pack 6.1.8r137981 added to the Extensions in Oracle VM VirtualBox Manager. In Oracle VM VirtualBox under Devices I select Insert Guest Additions CD Image and run it.  I get:   I read to check uname -r & it returned 3.10.0-1127.el7.x86_64  Also ls /usr/src/kernels* returned 3.10.0-117.8.2.el7.x86_64  yum list shows:   I read the post, but I haven't been able to resolve my problem.  How can I resolve the above errors and get Virtual Box Guest Additions installed correctly?


What is the right place to ask questions about the SmokeDetector?

is a bot which is run on several sites. (I think that it is run on the  , , , , maybe some other sites.) It seems to be a useful tool for several purposes. Occasionally, users might have questions related to this bot. I have seen that such questions . (For example: How can we get bot running in some particular chatrooms? What some particular message posted by the bot mean? How does it get the list of blacklisted sites, phrases, users? Can some commands be sent to the bot and if yes, can anybody do that? Which chatrooms do use this bot and what to do if users of some site want to start using it in their chat room? I guess there are many reasonable questions which could be asked by a user who does not have much previous experience with this bot.)  What would be the correct place to ask question about SmokeDetector?  Are such question on topic on this meta?  Would it be better to ask them in some chat room? Or completely elsewhere? Additionally, if questions about SmokeDetector are allowed to be asked here, is this topic important enough to have a separate tag? Or maybe tagging such question with something like  and  would be good enough? (In connection with tags I will add there semm to be two comment spellings  and . So somebody searching for posts about this bot would have to use at least these two possibilities to find all relevant posts using the built-in search.)


I just installed ubuntu 11.10 on a laptop of mine. Where do you turn on window autofocus on mouse hovering in this new version?  I used to be able to do it very easily in 11.04.  UPDATE: I'm looking for "Select windows when the mouse moves over them"


If the phrase "Thank you kindly,..." is considered archaic, could someone suggest an alternative?  Thanks  Bill


How do I install drivers for an Intel HD Graphics?

In System Info in 11.10, the graphics driver wasn't detected. I use ACER Aspire 4750 with Intel Core i3-2340M and Intel HD Graphics 3000 graphic card  How to install the driver for my Ubuntu?


Proving the functional equation $\theta (x) = x^{-\frac{1}{2}} \theta (x^{-1})$ from the Poisson summation formula

We have the relationship $\theta (x) = x^{-\frac{1}{2}} \theta (x^{-1})$  Now I know one uses the Poisson summation formula to prove this. The Poisson summation formula comes from Fourier Transform and series and satisfies, \begin{equation} \sum_{n=-\infty}^{+\infty} f(n) = \sum_{n=-\infty}^{+\infty} \hat f (n) \end{equation}  So do we say $f(n)= \theta(x)$? (where $\theta(x) =  \sum_{-\infty}^\infty e^{-\pi n^2  x}$)  So filling in we have, \begin{equation} \sum_{n= - \infty}^{+\infty} e^{-\pi n^2  x}= \sum_{m= - \infty}^{+\infty} \int_{- \infty}^{\infty} e^{-\pi y^{2}x}e^{-2 \pi i y m} dy \end{equation}  Now what is the best way to keep going? Do I rearrange with the goal of getting a Gaussian integral (and hence the relationship)? Or is there a more elegant way of achieving the desired result?  What I've done so far is, after completing the square in the power of the integrand, we have \begin{equation} =\sum_{m=-\infty}^{+\infty}\int_{-\infty}^{+\infty}e^{-\pi x((y+i\frac{m}{x})^{2}-i^{2} \frac{m^{2}}{x^{2}})}dy \end{equation}  Then separating the integrand, breaking it up into a product of exponentials again we have,  \begin{equation} =\sum_{m=-\infty}^{+\infty}\int_{-\infty}^{+\infty}e^{-\pi m^{2} \frac{1}{x}} e^{-\pi x (y+i \frac{m}{x})^{2}}dy \end{equation}  The left factor of the integrand is a constant as it does not contain $y$, so it can be brought outside of the integral.  $$ \sum_{n = -\infty}^{+\infty}  e^{-\pi n^{2} x} = \sum_{m=-\infty}^{+\infty}e^{- \pi m^{2} \frac{1}{x}} \int_{- \infty}^{+ \infty} e^{ -\pi x (y+i \frac{m}{x})^{2}} dy $$  What would be the correct approach from here? Should I make a substitution? Any help or suggestions will be appreciated!


I am working in Ruby on Rails. I have a Json String like this  "{\"user\":{\"email\":\"blah@blah.com\",\"name\":\"blah Test 1051\",\"mobile\":\"9999999999\",\"dob\":\"00/00/0000\",\"street\":\"somewhere\",\"state\":\"something\",\"city\":\"nowhere\",\"pincode\":\"50000\",\"Event_Code\":\"e0031\"}}"   I need to convert this to JSON hash like this   {"user"=>{"email"=>"blah@blah.com", "name"=>"blah Test 1051", "mobile"=>"9999999999","dob"=>"00/00/0000","street"=>"somewhere","state"=>"something","city"=>"nowhere","pincode"=>"50000","Event_Code"=>"e0031"}}


How do I keep my character centred on screen?

I am making a game similar to Legend of Zelda: Link to the Past (top-down 2D action-adventure). I want the character to stay centred on the screen when he moves.  Currently, whenever the player wants to move, I move all of the map in the opposite direction. This works, but as I add more objects to the world, moving them all gets more complicated.  Is there a better way of approaching this?


Past Progressive or Past Perfect Progressive?

In a past narrative, I often see people using Past Perfect Progressive for things that are still true, which is odd to me, as the Past Perfect Progressive is an action that started in the past and continued up until a point in the past. For instance  He asked calmly, scuffing his shoes on the carpet that hadn't been vacuumed for a long time  Shouldn't it be:  [...] wasn't been vacuumed for a long time  Since the Past P. is supposedly for things that stopped being true after some point in the past?


How to remove write protection from sandisk cruzer switch pen drive?

I have a sandisk cruzer switch pendrive. It is write protected. I want remove that write protection. I did Google very much i am not getting how to remove it. I tried on mac also but it didn't worked for me. So please can any one help me out to resolve this issue.? Thanks in advance.


js how to remove dynamically added row when clicking each remove button

this is html view, when i click on Add Row button it will add a row and it works. but when i click on delete button it wont remove row added. how to make it works?  <input type="button" id="addButton" value=" Add Row " />

        <input id="itemcode1" placeholder="Item Code 1" class="itmcode" />	         <input id="itemname1" placeholder="Item Name 1" />	         <input id="itemdesc1" placeholder="Item Description 1" />	         <input id="itemamnt1" placeholder="Item Amount 1" class="itmamnt" />	         <input id="itemqty1" placeholder="Item Qty 1" class="itmqty" />	         <input id="total1" placeholder="Item Total 1" class="total" />

          Running Total 	           <input name="running_total" id="running_total" />

   and this is the js     My Question is: Every thing is working fine but how to remove each row on clicking delete button?? please help


I'm a mobile Terraria player and I have heard of hard mode, and gotten it. Now I also heard of expert mode but I can't seem to find anyway to get it. How can I get expert mode on mobile Terraria?


What is difference between Partial Application and Currying?

I feel like this is the chicken and egg problem.  To make the comparison:  Currying:  x => y => z => u => value   Partial Application:  f_ab = (z,u) => value   From my understanding:          Currying creates a chain of unary functions.     Partial Application operates with functions of any arity.    Examples  const partial =      ( f, ...argList1 ) =>     ( ...argList2 ) =>     f( ...argList1, ...argList2 );  const curry1 = f => a => (...rest) => f( a, ...rest ); const curry2 = f => a => b => (...rest) => f( a, b, ...rest );    const curry = f => curryN( f, [] ); const curryN =     ( f, acc ) =>     acc.length === f.length ?     f( ...acc ) :     arg => curryN( f, [ ...acc, arg ] );    // Application sequence: // curry( volume ) // curryN( volume, [] ) // a => curryN( volume, [a] ) // a => b => curryN( volume, [a, b] ) // a => b => c => curryN( volume, [a, b, c] ) // a => b => c => volume( a, b, c )    const volume = ( a, b, c ) => a * b * c;   console.log( 'partial', partial( volume, 2, 3 )( 4 ) );  console.log( 'curry', curry( volume )( 2 )( 3 )( 4 ) );


How can I graphically show cos(A+B) = cosA cosB + sinA sinB?

How can I graphically show/prove that cos(A+B) is equal to cosA cosB + sinA sinB?


Help with interpreting coefficients in logistic regression

I am running some logistic regressions in R. I need some help with interpreting coefficients.   So, if my DV is 1 = yes and 0 = no, and I have five groups (a, b, c, d, e) and I make a the reference group (dummy coding), and the coefficient for b is significant and positive:   does this mean the odds of b saying yes compared to the odds of a saying yes is greater?  Or is there a greater odds of saying yes for group a compared to b?


How to get back Dropbox Icon xubuntu 14.04

I am asking this because I was wondering this all day and all the existing answers about installing libappindicator1 and logging out and doing dropbox stop && dropbox start in the terminal were NOT working


can't login to Ubuntu 14.04 LTS, just loops back to login screen (with standard desktop environment)?

My Ubuntu is in a login loop, there show a guest account however I had previously set Ubuntu to log in automatically, is. Not go to login screen. Initially it was stuck as I had set tightvncserver to start with rc-update but now after removing a new problem arises. Anyone have any ideas on how to fix?  I should mention that it seems to login as the desktop wallpaper changes, and I can access icons in top right of screen.  xsession errors:     CRITICAL: We failed, but the fail whale is dead. Sorry....      ERROR:gsm-manager code should not be reached


Oracle: OALL8 is in an inconsistent state

As part of upgrading JRun, we are moving from a 1.4 JVM to a 1.6 JVM. Now I am getting a really strange oracle db error: "OALL8 is in an inconsistent state". I have pinned down the problem to insert queries that do not use bind variables at all - all inline parameters. If I run the query without any bind variables, I get the above error. As soon as I replace one of the hard coded values with a bind variable - everything works without error.  The other strange bit is that after executing the query, it is in fact committed to the database. I can connect from another session and see the inserted row. I have tried wrapping the query in a transaction and it seems to succeed as the behavior is unchanged from the query without an explicit transaction.  Here are the relevant details:  Java Version: 1.6.0_12-b04 Virtual Machine Version: 11.2-b01 (HotSpot Server) Oracle Server: 10.2.0.4 Oracle Client: 11.1.0.7.0 through ojdbc6.jar    Update: I am using cfqueryparam - they are called bind variables in the oracle world. While that does solve the immediate problem, we have a rather large legacy code base that we can't realistically go through all of to update the queries as part of upgrading from CF7 to CF8.  Even though I have pinned down one specific situation that fails (and encapsulated it in an mxunit test) - that doesn't mean there aren't other areas where this may be an issue. I would really like to have a solution in place that removes the OALL8 error rather than coding around it.  Update 2: After checking with our DBA he had set a parameter called CURSOR_SHARING to SIMILAR. The Oracle default is EXACT. What is happening is when ColdFusion hands the query off to be executed, Oracle is turning all the literal values to bind variables and that appears to be confusing ColdFusion. Turning the setting back to EXACT allows the literal queries to work just fine.  Update 3: Oracle finally issued us an out-of-band patch for JDBC. It was identified as a JDBC error. The latest drivers should include it when they are finally updated. If you have support you can also request the patch through their TAR system.


Wierd NullPointer Exception in ExpandableListView

So I'm making an expandable listView with the following adapter:  class SubcategoriesAdapter extends BaseExpandableListAdapter {     @Override     public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {         View v=convertView;         if(v==null) v=layoutInflater.inflate(R.layout.tip_view, null, false);         ((TextView)v.findViewById(R.id.title)).setText(data.subcategories.get(groupPosition).tips.get(childPosition).title);         ((TextView)v.findViewById(R.id.content)).setText(data.subcategories.get(groupPosition).tips.get(childPosition).text);         return v;     }      @Override     public boolean isChildSelectable(int groupPosition, int childPosition) {         return true;     }      @Override     public int getGroupCount() {         return data.subcategories.size();     }      @Override     public int getChildrenCount(int groupPosition) {        return data.subcategories.get(groupPosition).tips.size();     }      @Override     public boolean hasStableIds() {         return false;     }      @Override     public Object getChild(int groupPosition, int childPosition) {         return data.subcategories.get(groupPosition).tips.get(childPosition);     }      @Override     public long getGroupId(int groupPosition) {         return 0;     }      @Override     public Object getGroup(int groupPosition) {        return data.subcategories.get(groupPosition);     }      @Override     public long getChildId(int groupPosition, int childPosition) {         return 0;     }      @Override     public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {         View v=convertView;         Tips.TipsSubcategory me=data.subcategories.get(groupPosition);         if(v==null) v=LayoutInflater.from(getContext()).inflate(R.layout.tips_subcategory_view, null, false);        /* ((TextView)v.findViewById(R.id.title)).setText(me.title);         Picasso.with(getActivity()).load(me.ad_url).into(((ImageView) v.findViewById(R.id.adImageView)));         Picasso.with(getActivity()).load(me.image_url).into((ImageView)v.findViewById(R.id.image)); */         return v;     } }   When I'm loading this Fragment that contains the list, I get the following exception:  java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.lang.String.equals(java.lang.Object)' on a null object reference     at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:715)     at android.view.LayoutInflater.rInflate(LayoutInflater.java:806)     at android.view.LayoutInflater.rInflate(LayoutInflater.java:809)     at android.view.LayoutInflater.rInflate(LayoutInflater.java:809)     at android.view.LayoutInflater.inflate(LayoutInflater.java:504)     at android.view.LayoutInflater.inflate(LayoutInflater.java:414)     at biz.energit.cookingfridge.user.fragments.TipsCategory$SubcategoriesAdapter.getGroupView(TipsCategory.java:148)   This line that it's pointing to, 148 is the line where I inflate the view:   if(v==null) v=LayoutInflater.from(getContext()).inflate(R.layout.tips_subcategory_view, null, false);   I tried removing the i, passing the actual parent instead of null, and getting the inflater from the fragment or via other means. I'm clueless.  UPDATE: Just in case someone has this issue again, I can't write an answer because someone marked this a duplicate. The problem was using <view instead of <View in the XML I was inflating. The compiler says nothing about it, but the issue mafiests itself this way.


Applied boolean modifier leaving shading artifacts with flat shading

I tried to manipulate a cube with the Boolean modifier. I tried to cut out an edge of the cube with a cylinder. Also, the shading result looks awful in FLAT SHADING mode, so I turned on SMOOTH SHADING.   Has anyone an idea how to achieve a better result. (I also cut out a Sphere first, this made the result less awful).   I used Blender Internal and rendered with smooth shading for smoothness.  Using flat shading looks okay, except the "round" cutouts :/  Face normals are okay.  First image is smooth shading.    EDIT: User Pisurquatre suggested the EdgeSplit modifier, works perfect to me (Maybe a little tweaking here and there):


Is it possible to spawn a random mob using commands?

I'm trying to create a button that when pushed, will spawn a random mob at a given x y z coordinates, but I can't seem to figure out how to pick a random mob. How would I do this?


Type safety: The expression of type Map[] needs unchecked conversion to conform to Map[]

I have the following two lines:  Map<String,Object>[] IEXDivMap = null;         IEXDivMap =  new Map[IEXJsonArray.length()];   and get the warning:  The expression of type Map[] needs unchecked conversion to conform to Map<String,Object>[]   Is there a way to fix that?  UPDATE:  I was asked in the comments why we need a Map array to begin with.  We are getting a series of hashmaps and placing each one inside the map array.  Here's the code:  @SuppressWarnings("unchecked") public static Map<String,Object>[] getDiv(String ticker) {     Map<String,Object>[] IEXDivMap = null;     try{         String url = "https://api.IEXtrading.com/1.0/stock/" + ticker + "/dividends/1y";          URL obj = new URL(url);             HttpURLConnection con = (HttpURLConnection) obj.openConnection();                con.setRequestMethod("GET");         int responseCode = con.getResponseCode();         if(responseCode == 404){             System.out.println("Ticker " + ticker + " NOT FOUND in getDiv()!");             return IEXDivMap;                         }else if (responseCode != 200){             System.out.println("IEX Printing All Response Header for URL: " + obj.toString() + "\n");             Map<String, List<String>> map = con.getHeaderFields();                         for(Map.Entry<String, List<String>> entry : map.entrySet()) {                 System.out.println("IEX " + entry.getKey() + " : " + entry.getValue());             }         }          BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));         String inputLine;         StringBuilder response = new StringBuilder();          while ((inputLine = in.readLine()) != null) {             response.append(inputLine);                      }         in.close();          JSONArray IEXJsonArray = new JSONArray(response.toString());                 IEXDivMap = new Map[IEXJsonArray.length()];          for (int i = 0; i < IEXJsonArray.length(); i++) {             IEXDivMap[i] = new HashMap<String,Object>();             JSONObject IEXJsonObject = IEXJsonArray.getJSONObject(i);              IEXDivMap[i].put("exDate",IEXJsonObject.getString("exDate"));             IEXDivMap[i].put("amount",IEXJsonObject.getString("amount"));              //System.out.println(IEXDivMap[i]);             System.out.println(IEXDivMap[i].get("exDate") + " 0  " + IEXDivMap[i].get("amount"));         }     }catch(Exception e){         System.out.println("FATAL ERROR: Something went wrong in getDiv " + e.getMessage());         System.exit(0);     }     return IEXDivMap;  }


Number of subsets of a set $S$ of n elements , is $2^n$

I know that Number of  subsets of a set $S$ of size n ,  is given by the binomial sum      $\sum_{k=0} ^n \binom{n}{k}=2^n$ ,  n=1,2,3,..   elements    how we could conclude of prove this formula ? how to prove that this gives the number of subsets . where did this formula come from ?   PS:- i know how to prove $\sum_{k=0} ^n \binom{n}{k}=2^n$


$\lim_{n \to \infty} n \int_{1}^{\infty} \frac{dx}{1+x^n}$, solution critique needed

I am particularly curious about exchanging the sum and integral in the third equation, if this is unjustified then please let me know.  We have that   $$\lim_{n \to \infty} n \int_{1}^{\infty}\frac{dx}{1+x^n} =\lim_{a \to \infty}\lim_{n \to \infty} n \int_1^{a}\frac{dx}{1+x^n} $$  Also   $$\frac{1}{1+x^n} = \frac{1}{x^n}\frac{1}{1+\frac{1}{x^n}} = \sum_{i=0}^{\infty}\bigg(\frac{-1}{x^n}\bigg)^i\frac{1}{x^n} =\sum_{i=0}^{\infty}(-1)^i \frac{1}{x^{(i+1)n}}$$  Since we are integrating for $x \geq 1$, the above series converges for every $x$ so we may integrate term-by-term to obtain   $$n \int_1^{a}\frac{1}{1+x^n}dx = n\sum_{i=0}^{\infty}\int_1^{a}\frac{1}{x^{(i+1)n}} \, dx$$  $$= n\left[\frac{1}{n-1}-\frac{1}{2n-1}+\cdots\right]-n\left[\frac{a^{1-n}}{n-1}-\frac{a^{1-2n}}{2n-1}+\cdots\right] $$  where the second term goes to zero as $n$ goes to infinity. Further, we have that   $$\lim_{n \to \infty}\frac{n}{nk-1} = \frac{1}{k}$$  so the first term becomes $1 -\frac{1}{2}+\frac{1}{3}-... = \ln(2)$. In conclusion we get  $$\lim_{a \to \infty}\lim_{n \to \infty} n \int_1^{a}\frac{dx}{1+x^n} =\lim_{a \to\infty} \ln(2) = \ln(2) $$  independently of $a$.


desktop files and Ubuntu software Center

Since 12.04, when additional software is installed, Ubuntu software center puts an icon in the launcher, representing a .desktop file in /usr/share/app-install/desktop/. This desktop file is not "overruled" by a (possible) local .desktop file in ~.local/share/applications.  My question is: Why is the initial icon (.desktop file) put there, and is not the default .desktop file used that is located in /usr/share/applications?


On bootup, filesystem check occurs and it stops at 61% and I am redirected to a page with the message you are in the emergency mode. I don't know what to do next.  This is the message that I get at the screen   You are in emergency mode. After logging in, type .......  Press Enter for maintenance (Or press ctrl+D to continue):   But when I press Ctrl+D it again directs me back to the same screen.


Reading Files Within a Jar(ZipInputStream, etc.)

I'm writing a game in java and all is working more or less well, as you would expect when coding, but one issue I have come across is reading the image and sound files into the game. I wrote a method that works really well within Eclipse, but as soon as I try to test it in a runnable jar (exported using Eclipse) my game gets stuck on the loading screen because it can't read the files. I realized the problem there being that you cannot create File objects within a Jar, you have to use streams. This could work, but the images/sounds are located within folders and I'm not very sure how you can read files within a folder with streams(i.e not knowing the amount of files). Because of this I have tried to rewrite the method using the ZipInputStream (I found this as recommended when looking for solutions prior to posting this). This is what the method looks like now:  imageMap = new HashMap<String, BufferedImage>();     String imagebase = "/images";     CodeSource src = PlatformerCanvas.class.getProtectionDomain().getCodeSource();     if(src != null)     {         URL jar = src.getLocation();         try         {             ZipArchiveInputStream zip = new ZipArchiveInputStream(jar.openStream());             ZipArchiveEntry ze = null;             while((ze = zip.getNextZipEntry()) != null)             {                 System.out.println(ze.getName());                 if(ze.getName().startsWith(imagebase) && ze.getName().endsWith(".png"))                 {                     loading++;                     imageMap.put(ze.getName().replaceAll(imagebase + "/", ""), ImageIO.read(this.getClass().getResource(ze.getName())));                 }             }             zip.close();             System.out.println("Finished Loading Images");         }         catch (IOException e)         {             e.printStackTrace();         }     }   However, this completely skips over the while loop because getNextZipEntry return null. I tried using the base Zip archive libraries, but someone recommended the Apache Commons libraries, but neither worked. My Jar setup is this:  Jar /game/gameClasses /images/imageFiles /sounds/soundFiles /whateverOtherFoldersEclipseCreated   So my question is this: Why isn't this current method working and how do I fix it? Or, how can I load the images/sounds in a different way that works? I have looked at many other questions and tried many different things, but none worked for me.


Sample size and confidence level to verify existing data

I understand that to many this will be a frustratingly basic question which will not require much thought, but hopefully there are a few who can answer it anyway.  I have various sets of data on spreadsheets. Some worksheets have 900 rows of data and some have 15,000. There are many columns to each row, but essentially one row is one 'record'. The significant thing is that for each set of data, there is a finite and known population size.   I want to set up a 'checking' plan to provide me with a level of confidence (ideally without a tolerance, but if I have to have one then I have to have one). Each row (i.e. each record) on each worksheet can be correct or incorrect. There is no numerical variance, it is simply whether the data provided on each row accords to the various hard copy documents, data and calculations which feed into it.  My objective is to be able to state that I have reviewed the data and can say, with a given % confidence (and potentially tolerance, but ideally not), that the sample size I have examined (n) represents the larger population (N).  The ideal answer would provide me with a simple worked solution, but also a reference or several references to the genre of statistics that this exercise belongs in, so that I can go on to research it further and understand the basis for the worked solution provided.  I understand that I may be looking at a huge sample size, but I want to investigate the various possibilities, for instance to be able to work the formula (optimistic that one exists) backwards to determine what % confidence I could have with an n sample size.    EDIT:   I have a spreadsheet with 1000 rows on it. In each row there is an invoice number and an invoice value, just two columns. I want to know whether all 1000 rows are correct, but I don't want to check all 1000 rows manually. How would I calculated a sample size for this (say 20, 50 or 75?) and what confidence level could I have that all 1000 were correct, if for example I checked 20 invoices and all 20 were correct.


Can a Force-sensitive person use the Force to communicate with other Force-sensitive people?

Apart from being a Force ghost, a power one can achieve only after a death, can one use the Force to "communicate" with the other Force-sensitive?  Imagine one scenario where Anakin and Obi-Wan were sent to a mission and they are separated on different parts of the planet or are even on different planets. All their means of communication (com-link and holographic messages) are broken. Can Anakin and Obi-Wan still communicate to each other using the Force?   It's not something like one shown in Empire Strikes Back where Luke sends a signal and Leia picks it up. It's kind of dedicated one to one communication. Is there any evidence in canon, that this power exists and is used?


I am using this code to return the contents of the php file but it doesn't work for some reason.   <?php include (get_stylesheet_directory_uri() . '/inc/serv_night.php'); ?>


How does Vampiric Touch interact with Resistance/Vulnerability?

As a follow on from   If I use Vampiric Touch against a creature resistant or vulnerable to necrotic damage, what happens? How much do I heal?


Snapping issues in Adobe Illustrator cs6

I'm having snapping issues in Adobe Illustrator. After checking the different snap options, nothing seems to help. There are moments when designing where the program won't let me snap to an exact point, and only just before or just after.       Can anyone tell me what would be causing this? And what might be able to be done about it? I've been working in Illustrator for years, and I've never had a problem like this before.


In Java, for a string x, what is the runtime cost of s.length()? Is it O(1) or O(n)?

I've been told that code such as:  for (int i = 0; i < x.length(); i++) {     // blah }   is actually O(n^2) because of the repeated calls to x.length(). Instead I should use:  int l = x.length(); for (int i = 0; i < l; i++) {     // blah }   Is this true? Is string length stored as a private integer attribute of the String class? Or does String.length() really walk the whole string just to determine its length?


if p value is greater than 0.05 for a variable, then why it is considered in multiple regression equation?

Suppose, I have performed multiple regression analysis on the following data set where X1 and X2 are independent variables and Y is the dependent variable.  And achieved the following multiple regression analysis table from where it is clear that X2 is not correlated with Y as the p-value is greater than 0.05 which is 0.108 for X2 variable  So,  if p value is greater than 0.05 for a variable, then why it is considered in regression equation Y = 2.709 + 0.763(X1) + 0.463(X2) which has been shown in any online multiple regression equation calculator. My question is Why it is not like the following Y = 2.709 + 0.763(X1) omitting the [0.463(X2)] part from the equation, as X2 is not correlated with Y Please help to clarify the conceptual idea....


Topographic Position Index unexpected result in QGIS

I am using Windows 7 enterprise and QGIS version 2.12.2 Lyon.  Have found an unexpected result when I use QGIS to generate a topographic position index (TPI) raster from a 30m by 30m DEM.  I find a pattern of what I believe to be aberrantly valued pixels forming a square grid pattern that are approximately 900 m on each side.  I expected the resulting raster to not have this grided appearance.  UPDATE: I have looked at my hillshade, slope, aspect, terrain ruggedness index and roughness rasters generated using the same tool and they all have this same "grid" (although it is much less apparent than in the TPI raster).  Here's a screenshot of the original DEM I used:   Here's a screenshot of the resulting TPI.  Notice the grid pattern formed over what I suspect to be an accurate TPI raster layer.   Here's how I created the TPI Raster: Raster – analysis – DEM:


What Are the Specific Elements that Distinguish Dark Magic?

In the question,  there is an excellent answer about how the difference is not specifically in the magic they use, but in the intent and the desires and personality of the person in question.  But magic, itself, doesn't have opinions or attitudes or desires.  Magic is a tool, and it's possible to use some magic for good or for evil.  There are the Unforgivable Curses, such as the Cruciatus, that are clearly dark magic because the only purpose is to make people suffer.  But is the line always so clear?  What are the specific elements that define a curse, enchantment, or charm, as dark magic?


What happens after the first 180 days in 180 /90 Schengen visa rule - multiple entry?

There is a lot of information about the 180/90 rule, but nowhere can I find what happens AFTER the first 180 days calculated from the first entry?  Let's say I have multiple entry visa for a one year period, and I was in Schengen for 30 days within the first 180 days period. After those 180 days (after my first entry), am I allowed to enter at all? Or just 60 remaining days, or maybe even another 90, till the expiration of visa?


Selecting taxonomy term in article and showing all articles titles associated with this term

I have a content type article and when editing an article there should be a field where you can select a taxonomy term of a specific vocabulary.   When viewing the article it should show a list of titles of all articles associated with the selected taxonomy term. I know how to make a select field and also a view to show the titles. But how do I send the selected term to the view and how do I display the view in the article?


If $x_1,x_2,\ldots,x_n>0$ and $x_1+x_2+\ldots+x_n=1$, prove that $$\frac{x_1}{1+x_2+x_3+\ldots+x_n} + \frac{x_2}{1+x_1+x_3+\ldots+x_n} +\ldots + \frac{x_n}{1+x_1+x_2+\ldots +x_{n-1}} \ge \frac {n}{2n-1}$$  This can easily be simplified: $$\frac{x_1}{2-x_1} + \frac{x_2}{2-x_2} +\ldots + \frac{x_n}{2-x_n} \ge \frac {n}{2n-1}$$  I could try using the Cauchy-Schwarz inequality: $$\frac{x_1}{2-x_1} + \frac{x_2}{2-x_2} +\ldots + \frac{x_n}{2-x_n} = \frac{x_1^2}{2x_1-x_1^2} + \frac{x_2^2}{2x_2-x_2^2} +\ldots + \frac{x_n^2}{2x_n-x_n^2} \ge \frac{(x_1+x_2+\ldots+x_n)^2}{2(x_1+x_2+\ldots+x_n)-(x_1^2+x_2^2+\ldots+x_n^2)}=\frac{1}{2-(x_1^2+x_2^2+\ldots+x_n^2)}=\frac{n}{2n-(x_1^2+x_2^2+\ldots+x_n^2)n}$$  It's left to prove that $$(x_1^2+x_2^2+\ldots+x_n^2)n \ge 1$$ or $$(x_1^2+x_2^2+\ldots+x_n^2)n=1$$I can continue using the Cauchy-Schwarz inequality again: $$(x_1^2+x_2^2+\ldots+x_n^2)n=(x_1^2+x_2^2+\ldots+x_n^2)(1+1+\ldots+1)\ge(x_1+x_2+\ldots+x_n)^2=1$$ So I've proved it myself. (I've shown this proof after editing, I didn't post the question with the solution in the details. I found the proof a while after putting the question here).


Recovering Wifi Password without Root on Galaxy Note 3

I am trying to recover WiFi password without rooting my phone. There are 2 ways I found online. One using a file explorer and the next is using ADB. I tried using ADB but I failed in doing so. I'm really not sure if I did it right but then I just followed the instructions here from . Anyway, I have pulled the wpa_supplicant.conf and this is the only thing I see:  update_config=1 eapol_version=1 ap_scan=1 fast_reauth=1   I should be seeing this instead of the one above:  network={ ssid="NETWORK_NAME_HERE" psk="PASSWORD_HERE" key_mgmt=WPA-PSK priority=1 }   Is there something that I missed or it's just not really applicable? I have Samsung Galaxy Note 3 SM-N9005.


Characters in url not placing the same name into variable in php

I am working with a url that has this name in it kãppã.  When I grab this name from the URL I need it to be kãppã then rawurlencode to k%25E3%25A3pp%25E3%25A3 The problem is when I try to access the name via variable it returns this b"kã£ppã£" Its coming through to the controller to a function via a parameter public function Profile($name, $region)  What can I do to keep the clean name in the URL but work with the encoded name in the function?


Unable to install XP or Win 7 Starter or even Ubuntu 10.10 on Lenovo Ideapad S10-3

I bought Lenovo IdeaPad S10. Loved it.. But it got very slow over time. So, I decided to install Ubuntu netbook edition on it. So, I formatted it.. And after that, it is not letting me install any OS, let alone Ubuntu.  I have tried XP also. Ubuntu fails with Kernel error message and XP fails during installation saying that it is looking for some file that does not exist on the disk.  Not sure what is going on.. Any ideas, folks?


I have a 64-bit Ubuntu. For the preinstalled Firefox I had to download the 64-bit plugins (, ); the 32 bit plugins didn't work. Then I downloaded Firefox from , which just has one version to download, and it does not state whether it is 32 bit or 64 bit (as of november 2010). Using this downloaded Firefox all the 64-bit plugins no longer work. I had to download the 32 bit plugins.  How can I tell whether my Firefox is 32 bit or 64 bit?


Clue #2: He’s making 10 sales a month. Even if I wrote pants-droppingly good copy for him and increased his sales by 200% — a % lift any CRO expert would blog & tweet about — this would only generate an extra $200 per month for his business:   what does "pants-droppingly" mean?


I am trying to solve a homework exercise in elementary number theory:     Which primes $p$ satisfy $n^2 \equiv -1 \mod p$ for a perfect square $n^2$?    After looking at the case $p=5$, I saw that $3^2 \equiv 4 \mod 5$, but $p=2^2+1$, I thought that maybe the answer would be primes $p$ such that $p=m^2+1$ for some $m$. Certainly this would imply that there is an $n$ so that $p \mid n^2+1$ (in particular $n=m$).  Unfortunately, $n=13$ doesn't satisfy that condition. However, weakening it to $p\mid n^2+1$ for some $n$ is just the statement of the problem. I don't want to answer "the congruence is true for primes for which it is true." So I am back to square one.


Adding a .tar.bz package to my local repository?

I downloaded a software package in a .tar.bz file.  I understand that I can install such packages through make install, but then there's no easy way to uninstall. Is there a way that I can add this package to my local repository, so that I can install/uninstall it through apt-get?


How to add both date and space to a filename

If I execute touch $(date '+%F %T'), I expect one file whose filename comprises the date and time to be created; but instead two files are created: one whose name is the date, and the other whose name is the time:  $ touch $(date '+%F %T') $ ls -1 12:39:26 2019-03-05   Why is this, and how can I create a file named 2019-03-05 12:39:26 instead, without using an underscore instead of a space?


What is the significance of "microcontroller based on microprocessor"?

I am aware about the basic theoretical differences between the two. Like micro controllers have ROM RAM memory etc., but microprocessor has none. But I am still confused.   Why is it said "A microcontroller based on microprocessor" (). If ARM is a microprocessor, then why STMs use it and call it as micro controller. What's the difference? Is eval board like "TI c-series launchpad" has a micro controller or a micro processor or both.   Kindly correct me if I am wrong anywhere.