Long-running cron task never fully executed

I am developing a Drupal Cron that has a very long-running task. First I tried with a simple Cron, which, of course, did not work because of "Memory exhausted" PHP fatal error.  Then, I developed a Batch with the Batch API which worked fine as a normal Batch. However, I could not make to run it completely inside the Cron. It receives the same PHP error.  After that, I developed a Cron using the Queue API. However, I could not make Drupal to run all queue jobs in the same cron. The execution stops at some point and I am unable to run more jobs. I know that there is an option to define the worker's function time, but my task is a long-running task. So it is limited by PHP.  I also tried to use Background Process module in order to execute my long-running task but it had the same problem as before: the execution stops at some point.  I am sure that the code can be executed completely. The only working way was through Batch page but I want to run it automatically every day (Cron).  Do you know how can I run a Cron until it finishes?  As I said, I tried with Batches and Queues but it did not work. PHP "memory exhausted" or timeout errors appear or the execution can be cut by Drupal.  Thank you.


Unmounting the partition currently in use

OK, here's my scenario: I'm dual-booting Ubuntu 17.10 and Windows 10, and I want to shrink my windows 10 partition, and allocate the free space to my Ubuntu partition. I have shrunk my Windows partition using GParted, now I need to extend my Ubuntu partition. Now, to do this, I figured I'd just go onto Windows 10 and extend my Ubuntu partition. Unfortunately, Windows 10 disk partitioning is super confusing and fiddly, so I'm trying to use Gparted instead. To extend my Ubuntu partition, I've been told I first need to unmount it, but I'm unsure whether to do this or not, as I don't want to unmount a partition that I'm in the middle of using.  tl;dr: Will unmounting the partition I'm currently using break my computer?  Sorry for the wall of text, and thanks for reading.  EDIT: I have tried using GParted live CD however I get tmp (7) errors, buffer I/O error and a few more. It will not boot in failsafe mode or safe mode.


I do have latest version of Ubuntu , and I would like to remove it to INstall Windows 8.1  but when I begin installing Windows , it tells me can't install in this partition because it's not NTFS or something ... what should I Do please ? Thank you


Resize Image in Photo Upload in Visualforce before save in attachment?

Good Morning Friends,  I am creating a Visualforce for my users to upload photos and these photos are saved in the attachments object, but I wonder if there is any way before the picture is saved I can give a resize the image to 800x600 when the image is larger than this size, if less is saved normally.  Could anyone help me in this task? Thanks to all


Single word request: to be burned at the stake

... Fiction writers (eye roll)  To be burned at the stake  If we can't come up with a verb, perhaps a corresponding noun or adjective would suffice.  15th century historical fiction, so modern terms such as marshmallowed wouldn't really help.  Here is my sample:  You, the accused, have been found guilty of practicing Judaism as a Christian. This heresy against our Lord Savior carries the penalty of ____(noun).  Or  [C]onvicted of heresy, you are to be ____(verb).


For which values of $p$ does the serie $\sum\limits_{n=2}^\infty\frac{1}{n^p\ln(n)}$ converge?

For which values of $p$ does the serie $\sum\limits_{n=2}^\infty\frac{1}{n^p\ln(p)}$ converge? I'm trying to use the ratio test but I can't get a simple term in which use limit easily enough.


Whats the most secure way to encrypt a string without the use of a computer?

I want to decrease attack surface by preventing the plaintext string or encryption key from ever being typed or otherwise entered into a computer. Ideally the decryption key would be something that the user can generate and store in their head. But encryption should still be as strong as possible. I don't need to be able to decrypt without a computer, though that would be cool.


The Disparate Clarification (newly coined term by me)

I'm curious if there is actually a term for what I have just deemed "the disparate clarification" -- for example I just saw a tweet that said "Let's party, and by party I mean scramble to figure out how to go to Mexico for cheaper healthcare." I think these types of sentences (not the content here) with such irrelevance are so funny but I don't know what they're called/ if there is a term !


When you kill someone, does your soul immediately split, or is there a process?

I've read the Harry Potter books many, many, many, many times, and this has never exactly been clear to me.  Do you need to do something in addition to murdering someone to make a Horcrux, or does it automatically happen?


Why can't the Polynomial Ring be a Field?

I'm currently studying Polynomial Rings, but I can't figure out why they are Rings, not Fields. In the definition of a Field, a Set builds a Commutative Group with Addition and Multiplication. This implies an inverse multiple for every Element in the Set.   The book doesn't elaborate on this, however. I don't understand why a Polynomial Ring couldn't have an inverse multiplicative for every element (at least in the Whole numbers, and it's already given that it has a neutral element). Could somebody please explain why this can't be so?


Prove that , any primitive root $r$ of $p^n$ is also a primitive root of $p$

For an odd prime $p$, prove that any primitive root $r$ of $p^n$ is also a primitive root of  $p$   So I have assumed $r$ have order $k$ modulo $p$ , So $k|p-1$.Then if I am able to show that $p-1|k$ then I am done .But I haven't been able to show that.Can anybody help me this method?Any other type of prove is also welcomed.


I created a Flow that sets actual completion date (today's date) into the corresponding stage date field(s) when Stage is changed. At the same time, it's not erasing the value when I assign a blank value for the date field in case stage goes backwards. Any clues? It's not letting me to set the value to null or empty string either.  * {!BlankDate} is a constant of date type with blank value. I've tried to assign value to blank date variable also with no success.


Do vouchers offered by EU airlines for Coronavirus cancellations turn into a full refund if not used?

My family's flights with AlItalia later this month have of course been affected by Coronavirus. We cannot get refunds, only vouchers are offered, as with basically all airlines at the moment. We booked through an agent, Supersaver. Now in the Netherlands, apparently government decided to allow these vouchers only with a few conditions, see . It includes the condition:  Flight voucher not used? Ask for refund! If you have accepted the flight voucher and you are not able to use it, you are entitled to a full > refund of the ticket price. The airline takes the initiative to repay  Has Italy also published rules for airline vouchers that include a statement on this? Has the EU?


What is the greatest common divisor of $0$ and $0$? On the one hand, ; on the other hand, , so $100$ should be a greater common divisor of $0$ and $0$ than $0$.


why this error has come ? "static declaration of function follows non-static declaration"?

I am learning about static function and as per rule if i declare function as  a static function then i can't access this function into other c file and if i try to access then there should be an error "undefined reference to `fun" so i declare and define static function into add.c and add.h file and call that function into main.c file but i am getting different error i.e "static declaration of 'fun' follows non-static declaration"strong text so my question is that why this error has come ???? please forgive me for my poor English !!!!  /************** main.c****************/     #include <stdio.h>     #include <stdlib.h>     #include "add.h"      int main(void)     {       printf("%d ", fun());       printf("%d ", fun());       return 0;     }  /***************add.c*************/      #include <stdio.h>     #include "add.h"      static int fun(void)     {       int a=5,b=4;       return a+b;     }  /*********************add.h*************/      #ifndef ADD_H_     #define ADD_H_      static int fun(void);      #endif /* ADD_H_ */


How can I change the durability of items using commands?

I have a Minecraft 1.8.1 vanilla server and would like to reward certain users. I would like to /give some users a 99999/99999 durability renamed Diamond Pickaxe (with all enchantments on it). How do I use commands to change/repair the durability of items? If possible, using only one command and use /give.


Apply jQuery function to each newly created (dynamic) element

I have a button that creates a dynamic textarea field with a unique id. Each time a new element is created, I want jQuery to trigger on those dynamic textarea fields.  I tried the .on('click') method and it doesn't run the jQuery on the dynamic element unless the button that generates them is pushed twice. So that won't work. Secondly, when I create a second dynamic textarea field, it doesn't work at all, even if I click the button twice.      jQuery('button').on('click', function() {         var dynamicElement = jQuery('.parentclass').find('textarea').attr('id');  //countChar is part of a function not displayed here (works fine).      countChar(jQuery('#'+dynamicElement).get(0));  //This code below never seems to apply itself to any dynamic textarea fields except for //the first one. It needs to apply itself to all of them and trigger each time a new //dynamic textarea field is created.      jQuery('#'+dynamicElement).keyup(function() {         countChar(this);     })      });   How would I go about making this work?  Thank you.    EDIT  Here is the function countChar (it adds a character counter and limits the characters too).  Function  function countChar(val) {     var allowed_length = 700; // character count limit here     var len = val.value.length;     if (len >= allowed_length) {         val.value = val.value.substring(0, allowed_length);         jQuery(".chars[data-textarea="+val.id+"]").text(0);     } else {         jQuery(".chars[data-textarea="+val.id+"]").text(allowed_length - len);     } }   HTML
                Custom Title                   Please enter the content of this field.         Remaining:
         <textarea rows="4" id="dynamic-textarea-1" class="textarea"></textarea>


modifying printindex to eliminate toc entry

I want to modify \printindex to eliminate the  \addcontentsline{toc}{chapter}{Index line so that an entry does not appear in the table of contents


In , I've found one solution to produce a zebra effect for listing. Unfortunately, this only works if the lines are not broken. Is there a way to fix this?  Here is a code with an example showing the problem:  \documentclass[10pt,a4paper]{article}     \usepackage[utf8x]{inputenc}     \usepackage{ucs}     \usepackage[T1]{fontenc}     \usepackage{lmodern}     \usepackage[frenchb]{babel}     \usepackage[x11names, svgnames]{xcolor}     \usepackage{graphicx}     \usepackage{listings}     \usepackage{amsfonts}     \usepackage{amssymb}      \makeatletter         % Patch line number key to call line background macro         \lst@Key{numbers}{none}{%             \def\lst@PlaceNumber{\lst@linebgrd}%             \lstKV@SwitchCases{#1}%             {none&\\%              left&\def\lst@PlaceNumber{\llap{\normalfont                         \lst@numberstyle{\thelstnumber}\kern\lst@numbersep}\lst@linebgrd}\\%              right&\def\lst@PlaceNumber{\rlap{\normalfont                         \kern\linewidth \kern\lst@numbersep                         \lst@numberstyle{\thelstnumber}}\lst@linebgrd}%             }{\PackageError{Listings}{Numbers #1 unknown}\@ehc}}          % New keys         \lst@Key{linebackgroundcolor}{}{%             \def\lst@linebgrdcolor{#1}%         }         \lst@Key{linebackgroundsep}{0pt}{%             \def\lst@linebgrdsep{#1}%         }         \lst@Key{linebackgroundwidth}{\linewidth}{%             \def\lst@linebgrdwidth{#1}%         }         \lst@Key{linebackgroundheight}{\ht\strutbox}{%             \def\lst@linebgrdheight{#1}%         }         \lst@Key{linebackgrounddepth}{\dp\strutbox}{%             \def\lst@linebgrddepth{#1}%         }         \lst@Key{linebackgroundcmd}{\color@block}{%             \def\lst@linebgrdcmd{#1}%         }           % Line Background macro         \newcommand{\lst@linebgrd}{%             \ifx\lst@linebgrdcolor\empty\else             \rlap{%                 \lst@basicstyle                 \color{-.}% By default use the opposite (`-`) of the current color (`.`) as background                 \lst@linebgrdcolor{%                 \kern-\dimexpr\lst@linebgrdsep\relax%                 \lst@linebgrdcmd{\lst@linebgrdwidth}{\lst@linebgrdheight}{\lst@linebgrddepth}%                 }%             }%             \fi         }     \makeatother      \lstset{ %    * Number for lines         numbers=left,                   % Where to put the line-numbers         numberstyle=\footnotesize,      % Size of the fonts used for the line-numbers         stepnumber=1,                   % Step between two numbers         numbersep=5pt,                  % How far the line-numbers are from the code % %    * Back returns for long lines         breaklines=true,                % Sets automatic line breaking         breakatwhitespace=false,        % Automatic breaks only happen at whitespace ?         breakindent=0pt,                % Space before the text of a break         postbreak=\mbox{                % Character used at the begining of a break             \rotatebox[y=0.9ex]{180}{\color{Red} $\Lsh$}%         },     }  \begin{document}  \begin{lstlisting}[language=Python,linebackgroundcolor={\ifodd\value{lstnumber}\color{gray}\fi}] for i in range(5): for i in range(5): for i in range(5): for i in range(5): for i in range(5): for i in range(5):     sum += i**3 print sum  print('Fin de la boucle...') \end{lstlisting}  \end{document}


I am looking for examples of finitely generated solvable groups that are not polycyclic. In  Baumslag-Solitar group $BS(1,2)$ is an example. But how to prove this fact?


I would like to understand why the integrals represent 2 things:   If we only do an integral without bounds on $f(x)$, the integral gives us the function $F(x)$ that, when differentiated, gives us the original function $f(x)$. If we do an integral with bounds $[a,b]$ on $f(x)$, it gives us the area under $f(x)$ by evaluating the difference $F(b) - F(a)$.   Why does $F(x)$ represent the area under $f(x)$ as well as the first point?


How to install Canon LBP2900C on Lubuntu? What I did using terminal is sudo dpkg -i [name of file inside debian] , and another installation terminal code. But it is throwing error saying dependency problems - leaving unconfigured Errors were encountered while processing: cndrvcups-common


If a unit and nilpotent element commute in a ring, their sum is also a unit.

Let $R$ be a ring (not necessarily commutative). Let $u\in R^\times$, (so $u$ is a unit), and let $a\in R$ be a nilpotent element. Show that if $ua=au$ then $u+a\in R^\times$.  I have that if $a$ is nilpotent, then $1-a$ is a unit. Then, I know that this means $\exists b\in R$ such that $ (1-a)b=1$. Additionally I have that $\exists c\in R$ such that $uc=1$. Then I was thinking maybe I could do some kind of algebraic manipulation like $uc=(1-a)b$ but that seems to only lead to dead ends.  Any hints or pointers in the right direction appreciated.


How to prevent fish disintegrating in frying pan

Twice now I've tried pan frying fillets of white fish (Swai and Flouder) in olive oil and butter.  Both times the fish has disintegrated into unsightly mush.  Is there some technique I'm missing?  How can I pan fry without the fish falling apart?


Proving that $\sum\limits_{n=0}^{\infty }\frac{1}{(2n)!!}=\sqrt{e}$

Proving that $$\sum_{n=0}^{\infty }\frac{1}{(2n)!!}=\sqrt{e}$$ Firstly, I tried to check the value with the exponential function at $x=.5$ but I found its terms not equal to the series terms.


This is not a question regarding which one should I use, but a rather a question about using the '==' operator.  Lets say I have this:  let stringNumber = '2'; let numberNumber = 2;   If I do this comparison:     stringNumber == numberNumber   Result is of course true. The '==' is doing type conversion, and that leads to two questions.   How big is the performance impact, when the '==' makes type conversion? Is the '===' doing any type of conversion at all, or just 'does it'?


"This is considered..." vs. "This is considered as..."

Does this "as" change the meaning or correctness of this sentence?     This is considered as socially desired.   This is considered socially desired.   Are both of them grammatically correct? Why or why not?


Give an example of a limit ordinal which is not a cardinal and show that it is not a cardinal.

By Definition 9.1.1. in my textbook it says that a cardinal is an ordinal such that for every $\beta \in \kappa$ there is no one-to-one function $f:\kappa \rightarrow \beta$. I found out that $\omega^2$ is a limit ordinal, because it is not a successor ordinal. Next, do I have to show that there exists a one-to-one function $f:\omega^2 \rightarrow \omega$ by contradiction to show that it is not a cardinal? Or what do I do for my next step? Any help is appreciated (I have already looked around at the site for similar problems).


How can I make this work with header files?

I have a very simple project. The file main.cpp creates a vector of floats, sorts them, then prints them.  I compile it with:  g++ main.cpp quickSort.cpp   If in main.cpp I change  #include "quickSort.h"   to  #include "quickSort.cpp"   it works fine.  How do I change this project so that it works with the header file?  main.cpp  #include <iostream> #include <random> #include <vector> #include "quickSort.h"  #define MODULO 200 #define SIZE 1500  int main(){     std::vector<float> data;     for(int i=0;i<SIZE;i++)         data.push_back(rand()%MODULO);      data=quickSort(data);      for(int i=0;i<data.size();i++){         std::cout<<data[i]<<',';     }     std::cout<<'\n';     return 0; }   quickSort.cpp  #include <vector>  template<typename T>  std::vector<T> quickSort(std::vector<T> data){      if(data.size()==0)return data;     int pivot=data[data.size()/2];      std::vector<T> a;     std::vector<T> b;     std::vector<T> c;     std::vector<T> ret;      for(int i=0;i<data.size();i++){         if(data[i]<pivot)a.push_back(data[i]);         if(data[i]==pivot)b.push_back(data[i]);         if(data[i]>pivot)c.push_back(data[i]);     }      a=quickSort(a);     c=quickSort(c);      for(int i=0;i<a.size();i++)ret.push_back(a[i]);     for(int i=0;i<b.size();i++)ret.push_back(b[i]);     for(int i=0;i<c.size();i++)ret.push_back(c[i]);      return ret; }   quickSort.h  #include <vector> template<typename T>  std::vector<T> quickSort(std::vector<T> data);


So, in the books we see the spell accio being used a few times to bring forth a desired object to the caster. However, we also see that to get the desired effect, one doesn't have to be too accurate in their description of the object (Harry says accio firebolt and his broom alone comes to him), and yet sometimes they get a range of objects that fit the description (Hermione calls for books about Horcruxes, and many of them come to her).  So I think that begs two questions.   What is the range of Accio? Could I call for something that was on the other side of the country? What about the other side of Hogwarts? How accurate is it? If I said "Accio Notebook" would it bring me my own notebook, or all the notebooks in the room?


Photos for OS X: How to generate album automatically at import

In iPhoto I relied heavily on the events feature. I had about 100 events. In Photos for OS X I'm totally ok with the new albums that replaces events somehow. But I am looking to automatically create an album of the pictures I import.  In iPhoto you could drag a folder into the program and it automatically created an event with the name of the dragged folder. Is there some similar mechanism to automatically create an album? The only way I found to create the similar behaviour is to drag a folder to Photos for OS X, import all of the photos, go over to the last imported section and create an album out of these images. Is there a better workflow?  Thanks in advance for any ideas.  Edit: I read the question here () but it doesn't help me very much unfortunately.


How to calculate number of possible key pairs in RSA

What determines the number of possible RSA key pairs for a given $n$? Is it because $\varphi(n)$ produces the number of values that are less than $n$ and coprime with $n$? Is it as simple as $\varphi(n)$?


Are the terminologies of score and principal component in PCA equivalent?

I am confused with the terminologies of score and principal component in PCA, it seems they are equivalent but there is also some difference. Could anyone explain to me?


Which Canon prime and teleconverters should I bring to a safari?

Currently I have the 70-300mm L lens from Canon.  I would like to go on a Safari trip, and was wondering, does it make sense to pick up the Canon EF 400mm f/2.8L IS II with the 1.4X and 2X Teleconverters which effectively allows me to reach up to 560mm + 1 stop and 800mm + 2 stops or just pick up the 600mm or 800mm prime lens from the beginning?  I know I am loosing a couple of stops, and image quality with the Teleconverters, but it allows me to have some what of a zoom function with a smaller package.  Thoughts?


How to search for a ppa for the non community version of cinelerra?

At this moment, the most recent version of cinelerra is 6.0. I performed apt-cache search cinelerra on my ubuntu with 0 results,  so I have to add a ppa which contains cinelerra.  There are two types of cinelerra, a less powerfull (so they say) called community version and a more powerfull heroine virtual (though I am noot 100 percent sure about this name) version.  I want to install the cinelerra - heroine virtual version.  My first step to add a ppa is usually to go to launchpad.net and perform a keywords search, in this case cinelerra ppa.  However, I am confused by the many search results and different namings, I am not quiet sure if I can spot the right version there.  Please help me by explaining what to pay attention to in the search results of launchpad.net or whether there are other sites to look for it.


How do I obtain the ebony blade and how do I power it up?

The ebony blade is a katana like two handed weapon in Skyrim.  Its apparently associated with one of the daedric quests, but which one, and how do I start it?  Also, once I obtain it, how do I power it up?


$G/N \cong G$ then $N = \{1\}$ with $G$ infinite.

This question similar to others posted before, but it is a particular case which I think can be solved differently. It was asked  or .   I need to proof the following:     If $G/N \cong G$ then $N = \{1\}$   Note that the finite case is very simple but what happens when $G$ is infinite?


$M= \{ A \in Mat_{2 \times 2}{\mathbb{R}}| \det(A)=1 \}$ is homeomorphic to $S^{1} \times \mathbb{R}^{2}$

Let's consider a group $M$ (under multiplication) of all matrices $A$ of size $2 \times 2$ over $\mathbb{R}$ so that $\det(A)=1$. How to show that the group is homeomorphic to the $S^{1} \times \mathbb{R^{2}}$?  Topology on $M$ is induced by the norm $||A||=\sqrt{x_{1}^{2}+x_{2}^{2}+x_{3}^{2}+x_{4}^{2}}$, where $A = \begin{pmatrix} x_{1} && x_{2}\\ x_{3} && x_{4}\\ \end{pmatrix}$ so it's the same as considering matrix as a point in $\mathbb{R^{4}}$. According to $Q = S^{1} \times \mathbb{R}^{2}$,, the topology on $Q$ is induced by the standart one from $\mathbb{R}^{4}$.   The common idea is to start with considering the $x_{1} x_{4} - x_{2} x_{3}=1$, but i can not find some rigorous ways how to conclude that it's precisely homeomorphic to $Q$.  Any help would be much appreciated.


How to use Terminal to delete all .svn folders recursively?

What command can I type into the Terminal so that I can delete all .svn folders within a folder (and from all subdirectories) but not delete anything else?


Difference between Lineage OS and Cyanogenmod : how does it affect current users?

Cyanogen said it plans to cease developing its open-source version of Android and will shutter its services by the end of the month. The company's blog mentions,     As part of the ongoing consolidation of Cyanogen, all services and Cyanogen-supported nightly builds will be discontinued no later than [December 31].    Do users get new update as OTA while using CyanogenMod, or do they have to completely erase and flash a new ROM? (That requires flashing new firmware, ROM, recovery etc.) What will happen, if users are continue using CyanogenMod after December 31, 2016?  What about bugs, security, stability?


Unable to load Linux after Windows installation

I installed Linux OS on the PC. After that, I installed Windows 7. Now, I am unable to load Linux again. How to install Grub in Windows 7?


Obtained a multiple entry US visa; Is a Canadian visa needed to visit?

My parents have a multiple entry US visa. They want to visit relatives in Canada. Do they need to obtain a Canadian visa? They are Indian citizens/passport holders.


How can I downgrade a package to an older version via apt-get?  Other tools are also acceptable but apt-get is preferred.


I would like to be able to defer the construction of the elements of a list until they are accessed for the first time. The obvious solution (using a generator as below does not work since it is iterable more than once, etc).   For example, the following prints 0 -> 9. I would like to print 0-> 9 twice.  def costly_build_function(i):     return i def my_function():     return (costly_build_function(i) for i in range(0,10)) tmp = my_function() # print 0 to 0 for i in tmp:     print i # print nothing for i in tmp:     print i


Chaining predicates to use inside .Where clause

I want to create EFCore query that will return all entities that meet some conditions for their related entities. For example entities look like this (that's pretty simplified example): public class MyEntity {    public int Id { get; set; }    public List<MyOtherEntity> OtherEntities { get; set; } }  public class MyOtherEntity {    public int Id { get; set; }    public int SomeProperty1 { get; set; }    public int SomeProperty2 { get; set; } }  And I have a method that takes array of simplified MyOtherEntity objects: public class MySimpleOtherEntity {    public int SomeProperty1 { get; set; }    public int SomeProperty2 { get; set; } }  Now I have some method that takes IEnumerable of these simplified objects, and I want to return all of the MyEntity objects that have in their relations MyOtherEntities that match all of the required conditions: public IEnumerable<MyEntity> GetMyEntitiesByMyOtherEntities(IEnumerable<MySimpleOtherEntity> entities) {    // example with some static values    // we want to find all MyEntities that have MyOtherEntity with value 1,2 AND MyOtherEntity with value 2,2    _dataContext       .Where(x => x.OtherEntities.Any(y => y.SomeProperty1 == 1 && y.SomeProperty2 == 2)                   &&                   x.OtherEntities.Any(y => y.SomeProperty1 == 2 && y.SomeProperty2 == 2)                   &&                   .                   . // and so on                   .)       .ToList();  The query above is translated correctly to SQL. I already created a solution with glueing some raw SQL parts that gives correct results, because it's just attaching AND EXISTS parts with proper subqueries. That being said I would (if possible) rather like to have it as some dynamic LINQ Where expression. SQL parser creates pretty much as good SQL as I would do for this example, but with raw SQL queries I lose some of the control that EFCore gives me. I created some list of predicates that I would like to chain together and inject into .Where: public IEnumerable<MyEntity> GetMyEntitiesByMyOtherEntities(IEnumerable<MySimpleOtherEntity> entities) {     var predicates = new List<Expression<Func<MyEntity, bool>>>();      foreach(var entity in entities)     {        predicates.Add(x => x.OtherEntities.Any(y => y.SomeProperty1 == entity.SomeProperty1                                                      && y.SomeProperty2 == entity.SomeProperty2);     }  }  Unfortunately I don't know how to chain them properly. I tried to use var combinedPredicate = predicates.Aggregate((l, r) => Expression.AndAlso(l, r));  But it has some casting issues (probably related to AndAlso returning BinaryExpression?) that won't allow me to do it in such simple way. How can I achieve that so it's not overly complicated?


why zero dimensional reduced ring are Von Neumann Regular?

i know that commutative VNR are zero dimensional and reduced.But i cant see the converse inclusion.can anyone help me?


What to do about my toddler who suddenly started screaming when I mention bathing or give her a bath?

I have an 18-month-old daughter. She loved having a bath from birth, and now all of a sudden she screams her head off when I mention bath or give her a bath. It's really stressing me out. I don't know what to do.


I want to be able to close an alert box automatically using Javascript after a certain amount of time or on a specific event (i.e. onkeypress).  From my research, it doesn't look like that's possible with the built-in alert() function.  Is there a way to override it and have control over the dialog box that it opens?  Also, I don't want an override that shows a hidden div as the alert.  I need an actual dialog box.


This question is from Herstein’s Topic in Algebra, page 166, question No. 8.     Prove that when $F$ is a field, $F[x_1 , x_2]$ is not a principal ideal ring.   I didn't understand, as no answer has been given in this post:    Any hints/solution will be appreciated.  Thanks in advance


Is it possible to have delegates declared in a loop perform different actions?  var buttons = new List<ImageButton>(); buttons.Add(FindViewById<ImageButton>(Resource.Id.button1)); buttons.Add(FindViewById<ImageButton>(Resource.Id.button2)); int count = 1; foreach(var button in buttons) {     button.Click += delegate {         Toast.MakeText(this, "I am " + count, ToastLength.Short).Show();     }     count++; }   The toast message always "I am 2" when clicking either button. Ultimately I would like to have a number of buttons performing slightly different actions when clicked.


bottomNavigation : ReselectedListener : Attempt to invoke virtual method on a null object reference

I am using bottom navigation in my layout but when I try to write an on Click for it in my main activity oncreate it gives me an exception:   Attempt to invoke virtual method on a null object reference   private BottomNavigationView bottomNavigationView;  @Override protected void onCreate(Bundle savedInstanceState) {     bottomNavigationView = (BottomNavigationView) findViewById(R.id.bottom_nav);      super.onCreate(savedInstanceState);     bottomNavigationView.setOnNavigationItemReselectedListener(new BottomNavigationView.OnNavigationItemReselectedListener() {         @Override         public void onNavigationItemReselected(@NonNull MenuItem item) {          }     });


Ubuntu is unbootable after upgrade to 18.04, can only access Windows 10. How can I reinstall Ubuntu without losing my files?

I was using Ubuntu 16.04 on a dual-boot computer, fortunately.   I attempted to upgrade from 16.04 to 18.04. Now my computer freezes during the boot-up procedure. There screen fills up with lines of code, then stops. I can't get it to do anything else. Therefore I have to boot to Windows 10.  It appears I will have to replace the entire Ubuntu partition. The question is how to do that without losing all my files and pictures.   Anyone have any ideas?


Is the co-domain needed if we have the range?

Why do we need the co-domain if we have the range? I know what both mean. Isn't it just better to use the range instead of the co-domain when defining a function? This question brought up to me when thinking about the definition of the surjective function.


Isn't commutative property of $+$ in a ring obvious from other axioms?

Suppose $R$ be a nonempty set and $+,.$ are binary compositions on $R$ such that (R,+,.) satisfies all the properties of a ring except the commutative property of $+.$ Then   $[(a+b)-(b+a)]=[(a+b)+(-b+(-a))]$ (using distributive law) =$[a+(b-b)+(-a)]=0.$  So $a+b=b+a,\forall~a,b\in R$  Thus we see that commutative property of $+$ is obvious from other axioms.  Why do we need still mention it in the definition of a ring separately?


Why gravity is an attractive force?     One may say that it is because of space time curvature but General Relativity is built on this law: $\displaystyle G \frac{m_1 \times m_2}{r^2}$ (To be more precise, it is  from it's potentiel form known as  that can be written like this: $\nabla \cdot g = - 4\pi Gp  $). So GR can't explain why gravity is attractive. General Relativity only explains how gravity occurs in terms of space time.    Another may stick with the Quantum theory stating that gravitons are responsible for the force of gravity, but why a massless particle with spin 2 will exchange positive momentum?


Why http://meta.stackexchange.com redirect to http://meta.stackoverflow.com?

I had a question about the similarity of question which is suitable for several site created on Area 51.  As they are no longer in beta since a long time, I was expecting to post them on the global meta site of stackexchange. I can understand the site don't exist, but why doing a redirect since it as absolutely nothing to do with .


What is the difference between Views and Materialized Views in Oracle?


Encrypted Home… Forgotten password, but I have the Passphrase

I have forgotten the password to log in to Ubuntu (15.10). My home folder is encrypted. I do have the passphrase. How should I change the user password? There are some procedures  but they do not mention if there is any difference if your home directory is encrypted. How to proceed?


In the films, was the portrayal of Captain America supposed to come across as gay?

Having just rewatched the Captain America films and being an occasional visitor to oddball websites I can't help shake the feeling that Chris Evan's portrayal of Steve Rogers comes across a bit gay (or bisexual really).   He clearly has a great affection for Bucky Barnes and is willing to do anything to protect him. Now this doesn't in and of itself make Steve gay, clearly he also has feelings for Peggy and later Sharon Carter. However, I don't know what it is, whether it is Chris Evans acting or what, but some of the scenes they share just give the impression that there is something more going there...  And I am not the only one.  and   So what is it? Is there something more, or as this video so puts it?                                  Not to be confused with a similar question. this question is asking directly about the portrayal in films, not the overall character.


MySQL using UPDATE ,SET,REPLACE string with UTF-8 format

I have this piece of code below and it's working fine, the issues is that when it goes up if I use bulgarian characters everything comes out like Ð¡Ñ‚Ñ€Ð°Ð½Ð°Ñ‚Ð° Ð½Ð° Ñ‡ÑƒÐ´ÐµÑÐ°Ñ‚Ð  But when I add bulgarian stuff from the admin menu (Opencart) display in Bulgarian.   The Database table 'name' is in utf8_general_ci.     <?php include 'config.php'; $servername = DB_HOSTNAME; $username = DB_USERNAME; $password = DB_PASSWORD; $dbname = DB_DATABASE; // Create connection $conn = new mysqli($servername, $username, $password, $dbname); // Check connection if ($conn->connect_error) {     die("Connection failed: " . $conn->connect_error); }   $sql = "UPDATE product_description SET name = REPLACE(name, 'The amazing spiderman Phone', 'Страната на чудесата')";  if ($conn->query($sql) === TRUE) {     echo "Record updated successfully"; } else {     echo "Error updating record: " . $conn->error; }  $conn->close(); ?>


Prove that $(n - 1)^2 \mid n^k -1$ if and only if $(n - 1) \mid k$

I need help!  I need to prove that for any $2 \le n,k$ positive integers $(n - 1)^2 \mid n^k -1$ if and only if $(n - 1) \mid k$  Thanks!


How to generate unique id's, without knowing other id's?

I'm implementing messages on an application (not realtime messages), and I have all the sending and receiving set up, but I'll make things a lot easier if I could generate unique id's for the messages before sending them to the server.   So because the id is generated before reaching the server, I can't know the other id's in order to make a new one. I could use a random string or something, of course the problem is that it's possible that sometime one of the id's repeats. But how do I make sure that that is very unlikely and it's not a gigantic string.


What "chmod 777 -R / " does in /var/www/html/.../.../.../?

Unfortunately I was rushing and ran sudo chmod 777 -R / inside one project. Should I worry that it started to add 777 permission for all my folder starting from root (/) ?


How to reduce icon size in Ubuntu 18.04?

I have a clean 18.04 install (not update from previous version), the icons in desktop and Show Applications are huge, how can I reduce it. I've tried to go to Nautilus, but I couldn't reduce it to below 50%, I found a solution, but it's for 16.04 (), is it the same for 18.04? Will this solution reduce only icons in Show Applications? TIA.


Given $n+1$ points $(X,Y)$ in a plane such that no two points have same $x$-coordinates. Show: $\exists ! f\in\mathbb R[x]$ s.t. $f(x)=y$


How can I write a unit test to determine whether an object can be garbage collected?

In relation to , I need to check whether a component that will be instantiated by Castle Windsor, can be garbage collected after my code has finished using it. I have tried the suggestion in the answers from the previous question, but it does not seem to work as expected, at least for my code. So I would like to write a unit test that tests whether a specific object instance can be garbage collected after some of my code has run.  Is that possible to do in a reliable way ?   EDIT  I currently have the following test based on Paul Stovell's answer, which succeeds:       [TestMethod]     public void ReleaseTest()     {         WindsorContainer container = new WindsorContainer();         container.Kernel.ReleasePolicy = new NoTrackingReleasePolicy();         container.AddComponentWithLifestyle<ReleaseTester>(LifestyleType.Transient);         Assert.AreEqual(0, ReleaseTester.refCount);         var weakRef = new WeakReference(container.Resolve<ReleaseTester>());         Assert.AreEqual(1, ReleaseTester.refCount);         GC.Collect();         GC.WaitForPendingFinalizers();         Assert.AreEqual(0, ReleaseTester.refCount, "Component not released");     }      private class ReleaseTester     {         public static int refCount = 0;          public ReleaseTester()         {             refCount++;         }          ~ReleaseTester()         {             refCount--;         }     }   Am I right assuming that, based on the test above, I can conclude that Windsor will not leak memory when using the NoTrackingReleasePolicy ?


Are there gotchas using varargs with reference parameters

I have this piece of code (summarized)...  AnsiString working(AnsiString format,...) {     va_list argptr;     AnsiString buff;      va_start(argptr, format);     buff.vprintf(format.c_str(), argptr);      va_end(argptr);     return buff; }   And, on the basis that pass by reference is preferred where possible, I changed it thusly.  AnsiString broken(const AnsiString &format,...) { ... the rest, totally identical ... }   My calling code is like this:-  AnsiString s1, s2;     s1 = working("Hello %s", "World");     s2 = broken("Hello %s", "World");   But, s1 contains "Hello World", while s2 has "Hello (null)". I think this is due to the way va_start works, but I'm not exactly sure what's going on.


Suppose $x_i>0$ for $i=1,2,\cdots,n$ and $x_1+x_2+\cdots+x_n=1 \ldots$

suppose $x_i>0$ for $i=1,2,\cdots,n$ and $x_1+x_2+\cdots+x_n=1$ show that $$\frac{x_1}{1+x_2+x_3+\cdots+x_n}+\frac{x_2}{1+x_1+x_3+\cdots+x_n}+\frac{x_3}{1+x_1+x_2+\cdots+x_n}+\cdots+\frac{x_n}{1+x_1+x_2+\cdots+x_{n-1}}\ge\frac{n}{2n-1}$$ attempt from the equalitys i could rewrite $1-x_1=x_2+\cdots+x_n$ and then $$\frac{x_1}{1+x_2+x_3+\cdots+x_n}+\frac{x_2}{1+x_1+x_3+\cdots+x_n}+\frac{x_3}{1+x_1+x_2+\cdots+x_n}+\cdots+\frac{x_n}{1+x_1+x_2+\cdots+x_{n-1}}=\frac{x_1}{2-x_1}+\frac{x_2}{2-x_2}+\frac{x_3}{2-x_3}+\cdots+\frac{x_n}{2-x_n}$$ but idk how to proced from there, so how do i solve this? the fact $x_i>0$ makes me assume AM-GM inequality could be used but idk how one would use.


Subgroups of $U(n)$ isomorphic to a direct sum of cyclic groups

Let $U(n)$ to be the set of all positive integers less then $n$ and relatively prime to $n$. Then $U(n)$ is a group under multiplication modulo $n$.  A. Find integer $n$ such that $U(n)$ contains subgroup isomorphic to $Z_5\oplus Z_5$.  B. Show that there is an $U(n)$ containing a subgroup isomorphic to $Z_3 \oplus  Z_3$, but not isomorphic to $Z_4 \oplus  Z_4$.


Do VAR and VEC require no unit-roots? I have three variables where two are difference-stationary (unit roots) and one is trend-stationary (no unit root). The three of them are cointegrated.   Questions:   1) Can I conduct VEC in the presence of unit-roots? 2) If yes, should I difference my variables to make them stationary? 3) Should I be conducting the Johansen test on differenced variables?


He staggered in, late as usual, his hair this way and his collar the other. His socks were as mismatched as were his principles. I thought to myself, here comes yet another disastrous sales meeting.  It seems to me too much to write :     I thought to myself 'Here comes yet another disastrous sales meeting'.   The Authorised Version deliberately did away with punctuated speech, retaining only the capital to indicate the beginning of a quote but leaving out quotation marks.  Can I therefore do the same in common writing, for my thoughts ?     I thought to myself, Here comes yet another disastrous sales meeting.   I cannot find another question on EL&U which covers this.


Do I need swap space if I have more than enough amount of RAM?

From what I understand, the purpose of a swap partition in Linux is to free up some "not as frequently accessed" information from RAM and move it to a specific partition on your harddrive (at the cost of making it slower to read from or write to), essentially allowing active applications more of the "high speed memory".  This is great for when you are on a machine with a small amount of RAM and don't want to run into problems if you run out. However, if your system has 16 GB or 32 GB of RAM, and assuming you aren't running a MySQL database for StackExchange or editing a 1080p full length movie in Linux, should a swap partition be used?


Do Stack Exchange sites have any sort of security bug bounty program?

Not that I have been looking for security issues or anything. I am just curious if they have a policy regarding people searching for and reporting potential security issues?


Note-taking and outlining using Vi: On startup, highlight tags and display tags in a preview window

I am using vi as a note-taking and outlining tool and therefore I thought that this stackexchange site would be appropriate to ask this question. I am constructing the "tags" file by myself. What I would like to do is that when I open my notes or outline file, vi reads the tags present in this file, highlights them and also displays the tag labels in a vertical preview window. I have no experience in vim scripting so I would appreciate some help.  Currently I am using a bash script to generate a tag labels file taglabels in $PWD using cut and loading it in a separate vertical window  My script looks like this  #! /bin/bash  cut -f1 $PWD/tags > $PWD/taglabels vi -c ":30vsp $PWD/taglabels" $1   As is obvious, the script does not highlight the tags present in the file nor does it show only the tags present in the file. On the contrary it shows all the tags present in $PWD/tags.  I looked into ctags and the taglist plugin but they seem to be more suited for code than for free-form text.  If anyone has any suggestions on how to improve on this scenario I would be grateful.  Thanks.


How do you package a final logo design for a client?

I mean once the logo is already approved, what is the most professional way to send them the logo — and what formats do you include?


How can I bring STAG back if I have 100% completion?

There's a couple of the Saintsbook challenges that require you to have STAG forces available to kill.  After you complete the game, however, the STAG forces are nowhere to be found.  I believe that you can fight a few more STAG forces if you replay the final mission, but I think my save is glitched, so that's not an option.    Is there any way post-game completion to bring STAG back?  I miss their much nicer tanks and VTOLs for hijacking :(


Where does Minecraft for Windows 10 store its data?

I have searched in %appdata%, pulling up the list of files there, but there is no file labelled .minecraft. Searching %appdata%\.minecraft returns "no results found".   I also opened Minecraft to click on the resources button and could not locate that either.


Why couldn't parseltongue be learnt and could Dumbledore understand it?

Parseltongue could only be spoken by certain wizards such as Gaunts, Voldemort, Harry (temporarily) and Slytherin. Why couldn't it taught like French or Latin? Why wasn't it a subject in Hogwarts? Ron could mimic it to open Chamber of Secrets. During the 6th book Harry visits Gaunt's house with Dumbledore in memory where he sees them talking in parseltongue. Could Dumbledore understand them and how?


Select row with max value from each group in Oracle SQL

I have table people containing people, their city and their money balance: id    city_id    money 1     1          25 2     1          13 3     2          97 4     2          102 5     2          37  Now, I would like to select richest person from each city. How can I do that using Oracle SQL? Desired result is: id    city_id    money 1     1          25 4     2          102  Something like that would be useful: SELECT * as tmp FROM people GROUP BY city_id HAVING money = MAX(money)


How to create a site based on custom web template ID not Name or title

How can I create a site using custom web template using c# and templates name and id in SharePoint 2013 ? I don't want to use web template title.


Associativty of smash product on compact spaces

Let $Y,Z$ be compact or $X,Z$ locally compact. Then the canonical bijection    $$ (X \wedge Y) \wedge Z \rightarrow X \wedge (Y \wedge Z) $$    is a homeomoprhism.    I can prove the case when $X,Z$ are locally compact using exponential law. But I don't see how one approaches the case when $Y,Z$ compact. Hints?


Create a list with initial capacity in Python

Code like this often happens: l = [] while foo:     # baz     l.append(bar)     # qux  This is really slow if you're about to append thousands of elements to your list, as the list will have to be constantly resized to fit the new elements. In Java, you can create an ArrayList with an initial capacity. If you have some idea how big your list will be, this will be a lot more efficient. I understand that code like this can often be refactored into a list comprehension. If the for/while loop is very complicated, though, this is unfeasible. Is there an equivalent for us Python programmers?


This is an example, of hyper-parameters search in a hypothetical python code. My question is How can I be sure that RandomSearch really will find the best parameters that lies within the top 5% of the true maximum, with 95% probability.  I read this , and its claims that with 60 iterations of random search I will find that 5% with 95% of probability. But that looks like a magic number and I don't know if that works just for any case or any type of problems without considering any other characteristic of the problem or the amount of hyper-parameters    import numpy as np from sklearn.model_selection import ParameterSampler #... lot of imports and code that doesn't matter right now parameters = {         "sequence_length": np.arange(50, 300, 50),         "vocabulary_size": np.arange(1000, 50000, 1000),         "embeddings_size": np.arange(64, 257, 64),         "dropout": np.arange(0.2, 0.8, 0.1)     }     param_grid = ParameterSampler(parameters, n_iter=60)      for grid in param_grid:         my_awesome_lstm_model.fit(parameters=grid)


Why is a new website/domain restricted on iOS Safari?

Edit 1: I'm sorry, but the answers provided in the  do not answer this question.   To clarify: I'm not asking how to whitelist a domain, I'm asking WHY a domain is blacklisted - seemingly without reason - in the first place when no explicit nor mature content can be found on it. It's imperative that the website can be acccessed on any iOS device, even if web content restrictions are in place, with no further user intervention.  EDIT 2: I've found that not all pages on our domain are blocked by this setting, so it seems iOS blocks a page based on specific content (words, images, etc.), maybe even certain HTML. Would be grand to know what exactly triggers the block.  EDIT 3: it's definitely the content. Once I remove all the main content from our website and just leave the header, footer, HTML tags, scripts etc. in tact, the website is accessible even with "Limit Adult Content" setting turned on. I've scoured the content but can't fathom what exactly causes this. The website text is in German (the HTML lang tag is set accordingly) and there's imo literally nothing that could be seen as adult content. Guess we'll just have to get in touch with Apple to figure this one out. Thanks though!    Original question:  I just launched a new website for a client. The website is aimed at teenagers from 12-14 and doesn't contain any explicit content whatsoever.   If web page content restriction are turned on in iOS, the website cannot be accessed with Safari and the following message is displayed instead:  You cannot browse this page at   "domain.com" because it is restricted   Why does this happen and what can we do about it? This makes no sense. The domain name in question is brand new, hasn't been used before and isn't on any blacklists as far as I can tell.  Any help is appreciated, we really need to get this website rated appropriately.


t seems that somehow our domain computers have been infected by rasomware, turning files into encrypted files ending with .crypted. Lots of file have been changed and we do have back up.  At the same time, scanning for actual malware/virus/trojan have so far not resulted with anything. I haven't scanned all the computers, but I did notice that the files that have been changed were only on shared folders.  I've tried a couple of tools because I have copies of the original files (at least some) but I cannot seems to be able to decrypt them. At least not yet.  I think - but I could be wrong, that maybe only one computer with access to all these shared folders is actually infected, and it's changed those file names. Is this possible ? No encrypted local files have been found yet on the computers I've checked.  How do I check ? any ideas ? the files have changed to "filename.exe.NUMBER{payfornature@india.com}. I tried communicating with the address - and some guy who knows where behind proxies is demanding for $5000.  Any ideas would be appreciated.


what does "an object reference is required for the non-static field, method, or property 'Random.Next(int, int)' mean?

The problem I'm having is that Visual studio is throwing an error under the code "Random.Next(1,10);" that says:      "an object reference is required for the non-static field, method, or   property 'Random.Next(int, int)' "   So, I looked at answers to other questions with similar phrases. In these examples on Stack Overflow most suggestions said that someone needed to simply make the method or class static. I tried all combinations of this in this code and it did not fix the error in Visual Studio.  Any help is appreciated, Thanks.  using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks;   namespace Data_Collector_Course_Assignment {     public class Device     {         // Returns a randoom integer between 1 and 10 as a measurement of an             imaginary object          public int GetMeasurement()         {             int randomInt = Random.Next(1,10);             return randomInt;         }     } }


acf(c(0,1,2,3,4,5),plot=FALSE) Autocorrelations of series ‘c(0, 1, 2, 3, 4, 5)’, by lag       0      1      2      3      4      5   1.000  0.500  0.057 -0.271 -0.429 -0.357    Why does the ACF output becomes negative as lag increases? My understanding is that no matter what the lag is, the series is in general increasing. Therefore the auto-correlation should be positive. For example, at lag 2, we are calculating the correlation function of the two series [0,1,2,3] and [2,3,4,5], where the positive correlation still holds. Where do I get this wrong?  Update  Here is my intuitive understanding of the acf of an monotonically increasing sequence:  ACF of a sequence is a function $\gamma(k)$ of the lag, k. By definition, this function indeed measures the correlation between $y_t$ and $y_{t-k}$. The misunderstanding comes from the understanding of correlation. A monotonically increasing sequence is not stationary, so the mean is not stable. In another word, the sequence does not exhibit mean reverting behavior. This distorts my usual understanding of correlation (when we think about the mean level at 0). Since the mean increases over time, those observations come earlier are more likely to be lower than the sample mean, thus inducing a negative sample acf when lag is larger.


What is the origin & meaning of "It used to drive me spare"?

While watching the eponymous documentary on Stephen Hawking, his wife described her husband's behaviour when he was deep in thought. She said he could be surrounded by children and not even notice what was going on. She then said, "It used to drive me spare." I got the gist that she meant it drove her perhaps crazy or to despair. Is this a British idiom? If so, how did it originate? Was there an omission in the phrase? How does one get to spare from annoyed/upset? I think that while the  is somewhat plausible, it is rather tenuous. To go spare (becoming unemployed) and being driven spare (getting angry) seems quite a leap to me. To me, even extreme anger and being distraught are two entirely different emotions. The link to loss of employment appears speculative in my mind.


Sum of divisors and Euler phi function of a number

I can very well see that all prime numbers satisfies this condition.  But what about other numbers, does there exist other solutions?  How do I find them?  Any help will be truly appreciated.


How to change the unusual font size of Table of Contents?

Below picture shows my table of contents  The title size (the word, Contents) is very big, maybe Huge. I never set it as Huge and I searched the whole LaTeX file, there is no the word "huge" at all.  And the number is start with 0, for example "0.1 Introduction", not the normal "1 Introduction"  Below is the only code related with ToC  \usepackage[subfigure]{tocloft} . . . \setcounter{tocdepth}{2} \tableofcontents   What problem it can be?  PS: I tried to use \usepackage{xpatch}, but this one does not work   I use report   \documentclass[a4paper,leqno,twoside]{report}   Thanks everyone! I changed report to article, the problem is gone!


Modifying width and precision of database using QGIS?

I have a database in txt format made of several columns of real numbers. Two column are integer, 17 are real (rounded to the first decimal) and 17 are real rounded to the second decimal.   If I import it through a txt format QGIS identified the integer columns properly, but also assign a width of 24 and a field precision of 15.   How can I limit it?


Why I cannot find a "Pure Cash" option in 401k investments?

I am of an opinion that I should decide where my money should get invested and if it should get invested at all or not.   When I looked at the investment options I have with my 401k money, I figured out that there are many Mutual Funds that I can choose from. But I couldn't find a "Pure Cash - No investment option" - what I mean by this is an option where my money is kept idle without investing in any kind of financial instrument (stocks, bonds, other MFs, currencies, forex etc etc whatever).   I wanted such kinda option because things may turn bad and I may want nothing invested in the stock markets/bond markets. I was thinking that if the market turns bearish then I would move everything to cash, but the cash option that is provided is not pure cash, it's again a fund basically which they call it as SF guaranteed. I dived in and investigated where this fund invests. Its portfolio consists of public bonds and mortgage loans and many other things. It means my money isn't getting invested as I want. There is no zero risk option! They have clearly mentioned that it has investment risk and it's not backed by any Federal fund. It's backed by the assets of the company that manages my 401k investments, duh! It's a private company. And who cares about that. I don't want any backing, I just want to keep my money in pure cash. Shouldn't I have an option to put my money into pure cash?   And if they aren't providing my an option why aren't they? What's their motive behind this?   What to do in such a scenario? My only point is I should decide where my hard earned money is invested. By giving all the options which in the end are investing in stocks/bonds/mortgage securities etc they are essentially telling me that all my 401k investment is subject to market risks! That's bad. There is no safe parking zone for turbulent times!  Any thoughts/advice would be greatly appreciated.


This is a confused part ever since I started learning electricity. What is the difference between electric potential, potential difference (PD), voltage and electromotive force (EMF)? All of them have the same SI unit of Volt, right? I would appreciate an answer.


Let $a,b,c>0$ such that $abc=1$. Prove the inequality $$\frac{1}{\left(a+1\right)^2}+\frac{1}{\left(b+1\right)^2}+\frac{1}{\left(c+1\right)^2}+\frac{1}{a+b+c+1}\ge 1$$    I proved $\frac{1}{\left(a+1\right)^2}+\frac{1}{\left(b+1\right)^2}+\frac{1}{\left(c+1\right)^2}\ge \frac{3}{4}$  and i also prove $\frac{1}{a+b+c+1}\ge \frac{1}{4}$ but unsuccessed


Union of a finite set and a countably infinite set is countably infinite

Ok, here is the problem statement:     Prove that if $S$ is any finite set of real numbers, then the union of $S$ and the integers is countably infinite.   This seems pretty obvious to me, knowing that 2 countable sets are countable.  But is there some step by step way to prove this?  Like do I need to prove bijectivity or something?  Thanks!


Looking for title of book about a man with nanomachines in blood

Back in the 90's I read a book and I have not been able to remember an author or a title, numerous searches have also found nothing.  I can only remember random details about the book. It is about a man who crash lands on a planet. He has nano machines of some kind in his blood that make him stronger, can heal a broken bone and administer morphine when he is injured, increase the length of his life, and they turn is skin a metallic color, I believe gold but maybe it was silver. They are powered by a power unit installed in the base of his spine.  The planet he crash(?) lands on plays a game involving tiles to work out their political issues instead of fighting wars, at the end of the book when they use the tiles to quickly advance technology to develop weapons.  At some point in the book/series the man gets imprisoned and has nothing to do but play the game, when he gets out of prison he has become a genius at it.  I would really love to reread this book, please help!


I have been testing the alpha iOS Stack Exchange app for about a week now, and I love it! You guys did an amazing job, which is not surprising considering the massive amounts of knowledgeable people who use this site. Nice work fellas.


Can I use the Linux 64 bit version of the Firefox update!?


I want to write an application which starts a .NET application depending on the computer supported .NET version. I think, I need to check the already installed .NET version and start the matching application.  Example:  I start a native C++ application which starts the correct VB.NET application for the currently supported .NET version.  My target: Get latest supported .NET version.


SEO - Website relaunch. Is it wiser to change things gradually?

I'm about to do a website relaunch in a couple of months. It's a WordPress site. The relaunch will include these changes:   changes in content, both text and images a new WP theme, thus changes in the DOM as well as design changes some minor structural changes   The domain luckily stays the same.  In terms of SEO I remember reading somewhere, that it is wiser to not change everything at once, but rather do changes gradually. Especially to not make changes with the content and the design/DOM at the same time. But I cannot find that same advise anymore anywhere.  So my question is: Is it better for your Google rankings to do all the above changes at once, or do them gradually, hence changing the theme first, than waiting 4 weeks or so and then doing changes to the content?


Taylor series for $\ln(\frac{1-z^2}{1+z^3})$ I've tried to $$\ln(1-z^2)-\ln(1+z^3)=\sum (-1)^{3n-1}z^{2n}-\sum(-1)^{4n-1}z^{3n}$$ I didn't manage to make it one series any help is good


Formerly Dead Dwellers Misbehaving (ungrateful peasants!)

The entire lower third of my vault is normally unoccupied and full of production rooms that exist solely to increase my power/food/water storage. Unfortunately, incidents do happen down there, so I send dwellers down there occasionally to squash roaches and choke Molerats to death with their delicious meats. Invariably, because of the horrible, horrible controls, some of them die. But I am not without compassion, so I revive them. That's when things go wrong.  I have done some testing, and dwellers seem to randomly choose one of three things to do after dying and being resurrected during an incident, after the incident is over. They either a) decide that being dead wasn't break enough and go idle (coffee break), b)return to their properly assigned work area (like all good dwellers should) or c) begin working in the room where they met their unfortunate demise.  No problem, right? Just wait till the incident is over, THEN revive them, right? No dice. They then either begin working in the room they woke up in, or go for coffee.  So my question. How do I predict what my dwellers will do after reviving? More importantly, how do I, if possible, force them to return to their regularly scheduled duties? (Removing rooms is not an option)


Is it a good idea to train a Neural Network on continiously randomly generated training data?

Hello everyone I'm building a license plate detection model in Tensorflow. I built a function that chooses a license plate at random from a collection of ~5000 plates and puts it in a random place in on a random background and saves the coordinates. At first I thought to generate about 40K images this way and train the network on with the generated data. But wouldn't it be a good idea to just continiously keep generating new data to feed to the network and basically eliminate any chance of it getting overfitted?


Comments/tips on a (non Latex) pdf including mathematical formulas

My goal : I correct copies from students that I scan to pdf. I wish I could make the annotations on the scanned copies rather than on the physical paper. Today, I have to scan the copies again to have my annotations transferable to students by email. Since most of the annotations are similar, I wish to have a stock of annotations I could transfer on the copies.  I went through a lot of technologies, including many "StackExchange Questions" here. I considered pdfcomment, cooltips, fancytooltips, the OCG family (ocgx, ocgp, ocg2, ...), etc.  Two tracks attracted more specifically my attention :    pdfcomments : I like the mouseover to see the comment, the capabillity to move the annotation around so I can have a stock on a pdf and I can copy it onto the scanned copies. This would be my choice if there was not a main drawback : it accepts only plain text when I need to use mathematical notations. (It needs selected pdf readers). Because you can move comments, you can put them on any pdf, even if it is not compiled from Latex or if you don't have the source. fancytooltips : I like the mouseover to see the comment, and the capability to use LaTeX mathematical formulas and images. Drawbacks : I can't move the annotation from a pdf document to the copies. (It works with very few pdf readers.) . I am not sure whether I can put tips on non Latex pdfs.   Is there a way to have pdfcomment have images/Latex mathematical formulas (or references to formulas that can show with a mouseover) ? Or is there a way to transfer fancytooltips to a non Latex pdf ? Or are there other techniques to achieve the goal ?


I know how to make a rectangle and fill it.   But what shoud be done to hatch this rectangle with thin 45 degree inclined line with 2mm gap.  \documentclass{article} \usepackage{tikz}  \begin{document}  \begin{tikzpicture} %\draw (0,0) rectangle (2,4); \fill[blue] (0,0) rectangle (2,4);  \end{tikzpicture}  \end{document}     Thank you Altermundus,   I want to hatch area under the curve. But I am unable to use your code as i did with      [pattern=north west lines, pattern color=blue]   Please give little explanation for your code so that i can use it.  \documentclass{article} \usepackage{tikz} \usetikzlibrary{patterns}  \begin{document} \begin{tikzpicture} \draw[pattern=north west lines, pattern color=blue] (0,0) rectangle (2,4); \end{tikzpicture}  \begin{tikzpicture} \draw [thick,pattern=north west lines, pattern color=red] (1,0)--(1,1) to [bend left] (4,4) -- (4,0) --cycle; \end{tikzpicture}  \end{document}


Why Requests per second in my vps is so low?

I have only build a wordpress on vps,to test the Requests per second with ab command.  ab -n 500 -k -c 50 http://www.mynet/ Server Software: Apache/2.4.6 Server Hostname: www.mynet Server Port: 80  Concurrency Level: 50 Time taken for tests: 65.799 seconds Complete requests: 500 Failed requests: 0 Non-2xx responses: 500 Keep-Alive requests: 0 Total transferred: 123500 bytes HTML transferred: 0 bytes Requests per second: 7.60 [#/sec] (mean) Time per request: 6579.858 [ms] (mean) Time per request: 131.597 [ms] (mean, across all concurrent requests) Transfer rate: 1.83 [Kbytes/sec] received   I have tested for many times . Requests per second take values from 7 till 10. Time per request take values from 6000[ms] till 10000[ms].    The cpu and memory is below 5% as top command show. Poor performance of vps ?


How can I smith higher levels of weapons?

Instead of only smithing weapons to exquisite, how I can smith better weapons? I have tried to use the weapon smithing skills constantly but I just can't figure it out.


How can $\mathbb{I}$ be uncountable and $\mathbb{Q}$ countable, yet $\forall a,b \in \mathbb{R} \exists r \in \mathbb{Q} : a<r<b$

I do understand the proofs, I've read, for the countability of $\mathbb{Q}$ and the uncountability of $\mathbb{R}$, but I don't intuitively understand how the set of irrational numbers can be uncountable, and is therefore, intuitively speaking, a lot larger than the set of all rational numbers, yet at the same time for all real numbers there exists a rational number such that the rational number can be put between any two real numbers. If this could be done for all real numbers, how can there be way more irrational numbers than rational numbers?


Does a study guide exist that starts from a "purely CS background" and advances towards "making a new quantum programming language"?

I am from a computer science background and I find it difficult to decide on the resources I should focus on while learning quantum computing, since there is so much to read/watch. My ultimate goal is to make a programming language acting as an interface between quantum computers and the person similar to 1972 when C was made. As a realistic intermediate stage, I would like to get to the point of writing programs on IBM's QISKit.  For that, I would need a schematic study guide in order to acquire the necessary background in Physics and the related fields required to dive into the field of quantum computing. Does this already exist: an ordered list of indispensable concepts and abilities to master, which if possible also mentions adequate material to acquire each of them?  Assume a high school level physics knowledge. Provide a study guide i.e. from beginner to expert kind of guide. Try to list video/book resources that one should follow in a chronological order so as to become an expert in the field of quantum computing to the level I can write my own quantum computing language (assuming already have other CS skills to write the language).


Why does upgrade from 12.04 to 12.10 using a CD/DVD still require download?

When I attempted to upgrade from 12.04 to 12.10, there was no autorun feature for the upgrade.  So I went into Update Manager, Settings, and clicked "Add Volume" and it added the DVD I had downloaded and burned.  However, during the upgrade it says "1,164M to download".   How can this be true?  I have almost all the packages on the DVD.  Is there something additionally I should do to avoid downloading?


Will reducing mysql permissions hinder WP function?

While installing WP, I created a mysql user to access only the relevant WP database.  It's likely that not technical people will end up with access to this account, so I decided to remove DELETE and DROP privileges from this user.  Was this a bad idea?  Will anything in WP not function correctly because of this.  Thus far, I got a couple of error messages during the install, but I looked up what they were doing, and that was precisely nothing.  The DROP queries didn't match anything they would have dropped.  UPDATE: It seems that my question is addressed by answers in this question:


Label axis in units of pi (or pi/2) and use minor tick num

Using pgfplots, I often want to label the horizontal axis major ticks in units of pi or pi/2, or pi/3. Is it possible to have such "trigonometric major ticks" use minor tick num = <value> to specify the number of minor ticks?  Currently my approach for "trigonometric major ticks" is to make a style wholes that specifies the xtick=<integer multiples of pi> and xticklabels=<labels>. I specify the ticks for a range -4*pi to +4*pi, and crop the graph as needed. I similarly have a style called halves for half-integer multiples of pi:  \documentclass{standalone}  \usepackage{pgfplots} %This package also loads tikz  \pgfplotsset{     % Global Styles     axis lines = middle,     xlabel = $x$,     ylabel = $y$,     no markers,     samples=50,     grid = both,     trig format plots=rad,     enlargelimits = false,     axis line style = {line width=0.5pt},     every axis plot/.append style={         line width = 1.25pt,         smooth,         },     % Label every pi     halves/.style={     xtick = {-12.5664, -10.9956, -9.42478, -7.85398, -6.28319, -4.71239, -3.14159, -1.5708, 0, 1.5708, 3.14159, 4.71239, 6.28319, 7.85398, 9.42478, 10.9956, 12.5664, 14.1372, 15.708, 17.2788, 18.8496, 20.4204, 21.9911, 23.5619, 25.1327},     xticklabels = {$-4\pi$,$-\frac{7\pi}{2}$,$-3\pi$,$-\frac{5\pi}{2}$,$-2\pi$,$-\frac{3\pi}{2}$,$-\pi$,$-\frac{\pi}{2}$,$0$,$\frac{\pi}{2}$,$\pi$,$\frac{3\pi}{2}$,$2\pi$,$\frac{5\pi}{2}$,$3\pi$,$\frac{7\pi}{2}$,$4\pi$,$\frac{9\pi}{2}$,$5\pi$,$\frac{11\pi}{2}$,$6\pi$,$\frac{13\pi}{2}$,$7\pi$,$\frac{15\pi}{2}$,$8\pi$}     },     % Label every pi     wholes/.style={     xtick = {-12.5664, -9.42478, -6.28319, -3.14159, 0., 3.14159, 6.28319, 9.42478, 12.5664, 15.708, 18.8496, 21.9911, 25.1327},     xticklabels = {$-4\pi$,$-3\pi$,$-2\pi$,$-\pi$,$0$,$\pi$,$2\pi$,$3\pi$,$4\pi$,$5\pi$,$6\pi$,$7\pi$,$8\pi$}     } }  \begin{document}  \begin{tikzpicture} \begin{axis}[wholes,domain=-pi:3*pi,ymin=-2,ymax=+4,minor tick num = 1]     \addplot {1-2*cos(2*x)};     \legend{$1-2\cos(2x)$} \end{axis} \end{tikzpicture}  \begin{tikzpicture} \begin{axis}[halves,domain=-pi:pi,ymin=-2,ymax=+4,minor tick num = 1]     \addplot[red] {2+0.5*sin(4*x)};     \legend{$2+0.5\sin(4x)$} \end{axis} \end{tikzpicture}  \end{document}    with output     Problem: I'm fairly happy with this solution, except minor tick num=1 is not working on the x-axis. I think this is due to rounding errors.   Certainly I could specify the minor ticks manually. I really don't want to do this---I need to create many graphs like this, some times I want minor tick num = 1, sometimes I want minor tick num = 3.  Is there a better approach?


I got the following error message from Software Updater:  The upgrade needs a total of 74,6 M free space on disk '/boot'. Please free at least an additional 68,3 M of disk space on '/boot'. Empty your trash and remove temporary packages of former installations using 'sudo apt-get clean'.   How can I get more disc space? I have   df -h Filesystem                    Size  Used Avail Use% Mounted on /dev/mapper/xubuntu--vg-root  454G   13G  418G   3% / none                          4,0K     0  4,0K   0% /sys/fs/cgroup udev                          1,9G  4,0K  1,9G   1% /dev tmpfs                         384M  1,3M  383M   1% /run none                          5,0M     0  5,0M   0% /run/lock none                          1,9G   24M  1,9G   2% /run/shm none                          100M   36K  100M   1% /run/user /dev/sda2                     237M  219M  6,1M  98% /boot /dev/sda1                     511M  3,4M  508M   1% /boot/efi


Can't use enter key shortcut on Google search results anymore

Up until last week, Google used to place a blue arrow on the first search result. Using the arrow keys, one could select different results. Finally, pressing enter would enter into the selected result. For the past few days, these keyboard shortcuts are no longer there. How do I re-enable them? I search on Google every 10 minutes and can't afford to waste 2 seconds each time pointing my mouse at the desired link.


What to wear for a PhD/ MSc thesis defense?

Is it better to wear formal clothes for a PhD or MSc thesis defense or can we wear something as simple as a T-shirt?


Is there a way to update all Java related alternatives?

Is there a way to quickly switch over all the Java related alternatives using update-alternatives?  For instance, if want to switch Java over to 7, I run sudo update-alternatives --config java and select the Java 7 OpenJdk. But if I run update-alternatives --get-selections | grep java I get the following,  appletviewer                   auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/appletviewer extcheck                       auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/extcheck idlj                           auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/idlj itweb-settings                 auto     /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/itweb-settings jar                            auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/jar jarsigner                      auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/jarsigner java                           manual   /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java javac                          auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/javac javadoc                        auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/javadoc javah                          auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/javah javap                          auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/javap javaws                         auto     /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/javaws jconsole                       auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/jconsole jdb                            auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/jdb jexec                          auto     /usr/lib/jvm/java-6-openjdk-amd64/jre/lib/jexec jhat                           auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/jhat jinfo                          auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/jinfo jmap                           auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/jmap jps                            auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/jps jrunscript                     auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/jrunscript jsadebugd                      auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/jsadebugd jstack                         auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/jstack jstat                          auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/jstat jstatd                         auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/jstatd keytool                        auto     /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/keytool native2ascii                   auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/native2ascii orbd                           auto     /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/orbd pack200                        auto     /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/pack200 policytool                     auto     /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/policytool rmic                           auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/rmic rmid                           auto     /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/rmid rmiregistry                    auto     /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/rmiregistry schemagen                      auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/schemagen serialver                      auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/serialver servertool                     auto     /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/servertool tnameserv                      auto     /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/tnameserv unpack200                      auto     /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/unpack200 wsgen                          auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/wsgen wsimport                       auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/wsimport xjc                            auto     /usr/lib/jvm/java-6-openjdk-amd64/bin/xjc   As you can see, my Java alternative was switched over to 7, but every other alternative based on OpenJDK 6 was not switched over. Sure I could switch each one manually or write a script to do so, but I assume there is a better way to accomplish this.


Autostart click-once winform application network deployed

I need to autostart my c# click-once winform application, but such that when autostarted that it is still ApplicationDeployment.IsNetworkDeployed = true.   Currently i autostart my app using:   RegistryKey rkApp = Registry.CurrentUser.OpenSubKey("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run", true);  if (!IsStartupItem())                 // Add the value in the registry so that the application runs at startup                 rkApp.SetValue("myApp", Application.ExecutablePath.ToString());   But when application is started i get ApplicationDeployment.IsNetworkDeployed = false


Why I can't vote again, unless there's an edit to post?

What is the reason behind not letting people vote again on the same post (for example -- after changing mind, i.e. downvote after previous upvote, upon further reading or after certain comments)? What this suppose to do, what prevent or in what this should help?  I can't vote again on post, where I have already voted, but I can... edit this post, do some really tiny change and then I can vote again, without any restrictions. Where's the logic?  EDIT: Neither  nor  (which most of you takes incorrectly as dupe) answers my question. I'm not talking about poor edits etc. I'm precisely asking, why I (with 2k+ rep) am blocked with this restriction, which I can very easily override by doing simple edit? In this case, 2k+ users shouldn't have this dual-voting restriction at all. This question has nothing to do with poor edits or tactical voting. It addresses  -- voting again after changing mind, after explanation by post author made in comments.


Which Broadcom driver to use for BCM43142 adapter in Ubuntu 16.04 (xenial xerus) LTS?

I recently upgraded to Ubuntu Xenial from Trusty, and am having trouble with my broadcom wireless adapter. I am currently using the bcmwl-kernel-source driver. The wifi works but keeps getting disconnected very frequently.   To troubleshoot I have tried to switch off the power management for the device. I have shifted from NetworkManager to wicd. I have tried the alternative, firmware-b43-installer, driver which doesn't work at all.  I understand that a comprehensive answer () exists on installation of broadcom drivers but the information presented there might not be pertinent to Xenial.


Science fiction novel involving Hindu (?) deities

I read, many years ago, a novel that I'd quite like to find again. I only recall fragments - the main one being that the protagonists were humans, possibly space travellers, who had somehow acquired divine powers, modeled over what I perceived as Hindu deities; the one name I remember was Agni. They were not divine all the time, but could take on the 'aspect' of their god.  This is all I remember with any certainty - there is one other bit that may be from the same story (but then again, possibly not): the Buddha is a person, who has been 'uploaded' into some sort of 'cloud' that represents Nirvana, and is downloaded at some point.


What happens when people are adamant on closing and not closing a question?

Imagine a situation where there are 10 people 5 of which adamantly want to close a question, the other 5 adamantly want it to remain open.  So the first 5 people cast close votes and the question becomes closed.  Then the next 5 people case reopen votes and the question is reopened.  Now what happens?   Can the first 5 people vote to close again? or can only different users vote to close now?  What happens if the question keeps getting closed and reopened?


My job has recently started to involve a lot more cryptography.  I would like to be become more familiar with the mathematics behind it, and so I would like to learn the basics of group theory.  Please can anyone recommend any good resources (preferably books!) for someone who is self learning this subject.  Any help greatly appreciated!


How do I restore files to previous states in git?

Given the following interaction:  $ git add foo  $ git commit -m "Initial import of 'foo'" $ rm foo # This could be any destructive action on foo, like editing it.   How do I restore 'foo' in my working copy? I'm looking for something like:  $ git <magic> foo Restored foo to revision <blah>.


Prove two reflections of lines through the origin generate a dihedral group.

Let $l_1$ and $l_2$ be the lines through the origin in $R^2$ that intersect in an angle π/n and let $r_i$ be the reflection about $l_i$. Prove the $r_1$ and $r_2$ generate a dihedral group $D_n$.  Attempt:  So $D_n$ is the dihedral group of order 2n generated by $ρ_θ$, where θ = 2π/n, and a reflection r' about a line l through the origin.  The product $r_1r_2$ of these reflections preserves orientation and is a rotation about the origin. Its angle of rotation is ±2θ.  Could I just say that by the definition of the dihedral group, we need to find a reflection and a rotation which fit the descriptions?


Universal factoring method or list of methods (trinomials)

I am a student in calculus II. I'm now failing tests solely because I cannot factor; I understand everything else. This is compounded by the fact it seems to exceedingly hard to find anything comprehensive online. This is a long-running problem I've been facing; I can't be the only one.  I know some methods, but I always run into more problems I can't factor. I know about synthetic/long division, binomial/perfect square trinomial factoring, difference and sum of cubes and squares, the grouping method, the quadratic formula (unsure how to use for factoring), guess and check, and some trinomial methods. I only know the difference/sum of squares/cubes well. For example, I can't factor $4x^2 - 4x - 3$.  It would be dandy if I could get a comprehensive list or a universal solution to all these factoring questions, but that's unlikely to happen (and would be too broad). I'll narrow this down to something more tangible: What are the methods I should know to factor trinomials?


It's quite usual to read :  "the time needed to factor n by NFS algorithm is exp(...formula with ln(n)...)"  But I can't find to which unit of time this formula refers ? Is it really time ? Or number of operations ?   Thanks


Installing Windows 7 on a new Ubuntu computer

I just received a new Alienware computer with Ubuntu pre-installed, since updated to version 12.04.  I would like to install Windows 7 or 8 (I have installation discs for both) to run some programs.  Any advice for a Ubuntu novice on how to do this?  Thanks!


I am new to lightning datatable, Using soql query we can get up to 50000 records, but is there any limit to show these records using lightning:datatable in lightning component ? If yes then how many records can be showed on one page without using pagination.


minimize all windows by pressing windows with d in ubuntu like windows

How can i minimize my all open windows by pressing windows+d in Ubuntu? I can do this in windows easily but with Ubuntu i do not know how to do.


Why do I get the same output with Poisson GLM vs quasi-Poisson GLM?

I have a Poisson GLM in R that is overdispersed, so I fit a quasipoisson GLM, however the residual deviance nor the degree of freedom change. Can that happen? What does it mean in that case?


I tried to make the following singleton class in C++  #pragma once #include "stdafx.h" #include <iostream>  class God { private:     static God* firstObject;     God()     {         if (firstObject != NULL)             firstObject = this;     } public:     static God* BuildGod()     {         if (firstObject != NULL)             return firstObject;         else {             God();             return firstObject;         }     } };   and then use it like so  God* a = God::BuildGod();   Unfortunatley, it won't even compile and it returned the following errors:     LNK2001 unresolved external symbol "private: static class God * God::firstObject" (?firstObject@God@@0PAV1@A)      LNK1120   1 unresolved externals


I get recently banned from flagging. But it's not quite clear to me why? In addition is there any way to recover from this ban? Will it age away and after 1-2 weeks it will be possible again?  I'm not quite sure what I'm able to do, to solve this?  This is my flag history:  36  moderator attention flags 5   waiting for review 20  deemed helpful 5   declined 4   disputed   I have 20 helpful and 5 declined. This is around 20%. Anyway, I don't get the point why some of the 5 were declined. Some posts were flagged to move them to another community or to close them as they are too broad/unclear. In fact, 3 of the 5 are closed/on hold or have a really low rating, but my flag was declined. And one which was mentioned to move to another community was also declined, but the answer is currently moved. So, why the hell I'm banned? Just because of some flag reviewer which really don't care about their reviews and quickly decide that flags are not helpful?   I just had 3 questions today which should be flagged due to off-topic and one because of spam (advertisement for a website). But yes, I can't flag them. Great job. This means that you just achieved that someone who was helpful for your community, just gets annoyed and won't help anymore.  I know there are some other posts like that, but not exactly on this case.  Hopefully someone can describe how to "unbann".


Circular duplicates in the close review queue?

I just got this error message:    Fair enough; I wasn't really paying attention to the duplicate link at the top of the suggested duplicate, just at the contents.  However, this question is  review queue with a vote to close as a possible duplicate of the question that got closed as a duplicate of this one.  Can we exclude these posts from the review queue (or if it's not easy, run a job to get rid of them)? As circular duplicates are  they'll just languish in the queue forever; generating confusion and more meta posts like this one (or ).  P.S. I clicked do not close; this isn't a question about what to do in this situation.


Dealing with data that spreads across UTM Zones?

I have data that spreads across two UTM Zones GDA/MGA94 UTM Zone 55 and 56. I have layers such as a cadastre, roads, pipelines etc where I want to store measurements like lengths and areas in metres or some kind of metric notation, not degrees!  Whats the best way to manage this in PostGIS (i'm using PostGreSQL 8.4 PostGIS 1.5)?  Should I be storing my data as GDA94 Geographic coords and using some sort of work around to calculate the measurements I require?  Or is there another way to handle this?


How do I make a symbol for the length of a line or vector? I intend the following notation: |AD| is the length of AD. I can't find this symbol anywhere. (When I use shift+backslash in LaTeX, it gives a horizontal line).  For some reason the \cdot also doesn't seem to work, when I write it down like this:  &|AD| \cdot |BD|& = ...   So can anyone please tell me what I am doing wrong?


How do I figure out which size chain my fixed gear bike has

My fixed gear bike is going to want a new chain soon, how do I figure out which width I should use?


Creating a range of numbers from 08 to 10 in bash doesn't include 0 in front of one digit numbers

On my local machine, where I run CentOS 7.2, when I do this:  for i in {8..12}; do echo ${i}; done   I got:  8 9 10   But when I do this:  for i in {08..10}; do echo ${i}; done   I got:  08 09 10   But on server to which I have access, which runs CentOS 5.6, running both commands results in the same output:  8 9 10   Why there are no zeroes in front of 8 and 9? Is it because of bash version, or just environment configuration? Can I change it per session or permanently, so my server will put that zero in front of numbers smaller than 10?


I have British passport transit time from Sydney flight to London 8 hours 5 mins do I need transit visa?

Do I need transit visa for 8 hrs 5 mins transit time at Sydney for flight to London Heathrow?


Can anyone provide some pseudo code for a roulette selection function? How would I implement this: I don't really understand how to read this math notation.I want General algorithm to this.


jquery onchange is not working on dynamically added elements

I am trying to set on change listener to some of the elements which are dynamically added but it's not working.  This is my html file:  <!DOCTYPE html>               <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">         <title>Cool Maths</title>         <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">                                                                          <link rel="stylesheet" href="css/createLevel.css" >

 Cool Maths

Create Module

All Modules

Create Level

             <form >                 <input type="text" id="level-name" placeholder="Level Name" class="form-control">             </form>
             <button onclick="newQuestion()" class="btn btn-primary" id="add-question-button" >Add Question</button>

             This is my javascript file:      var i = 0;   $(document).ready(function(){  });     function newQuestion(){          //I am trying to set on change listener to these elements  var newQuestionHtml = "
"+"Question no "+i+"
"+        "<textarea class='form-control' type='text' id='question"+i+"' placeholder='Question'></textarea>
"+        "<textarea class='form-control' type='text' id='hint"+i+"' placeholder='Hint'></textarea>
"+        "<input class='form-control' type='text' id='answer"+i+"' placeholder='answer'>
"+        "<button class='btn btn-danger' onclick=''>Add Step</button>
";         $("#all-questions-container").append(newQuestionHtml);       var question = new Question(i,"","","","");      var controller = new Controller(question);       //this line sets on change listener for the textarea with id question0 which was dynamically added      $("#answer0").on('change',function(){        alert("changed");      });   i++;  }   The elements are being added but when the value of the textarea is changed alert is not being displayed. Can anyone please tell me where I am going wrong?? Thank-you


How immutable dto serializaed/deserialized in java?

Consider a code:  public class MyDto implements Serializable {     private String myField;     public MyDto (String myField) {         this.myField = myField;     }  }   As I see this code works (I hope), but I have no idea how java serialization/deserialization construct object before it sets fields. Any idea?  About duplication  I have not found any constructor or immutable key words in  page. So this question is a bit different. Also  describes difference between json/xml etc not some specific feature to java serialization.


My main account got messed up, as I tried to fix it things went downhills.   keyboard mess - tried unity --restore and deleting .gconf2*, fail deleted .* in ~, total havoc. Chromium and Firefox crashes etc.   Now, another user account is fully functioning, but I really want my regular username back.  Is there any way to completely wipe the settings for the messed up account or copy the profile from the functioning user?


Given a group $ G $, how many topological/Lie group structures does $ G $ have?

Given any abstract group $ G $, how much is known about which types of topological/Lie group structures it might have?  Any abstract group $ G $ will have the structure of a discrete topological group (since generally, any set can be given the discrete topology), but there are groups that have no smooth structure. An example of this from Wikipedia is the group $ \mathbb{Q} $ with the subspace topology inherited from $ \mathbb{R} $. Which groups can occur as Lie groups? Are there specific families of groups that are known to have no smooth structure?  Similarly, how much can we know about the possible topologies on an abstract group $ G $? For example, which types of abstract groups admit a nontrivial (i.e., not the usual compact case) group structure?  In particular, I am curious about the extent to which properties of the abstract group determine properties of any associated topology/smooth structure.  Does anyone have any good references or a succinct answer for this question?


How to get list of files opened by a process in Windows?

Windows tool Handle.exe created by Mark Russinovich () can be used to get the list of files opened by a process.  In my app I need the same feature - I need to know list of files opened by a different process.  How to implement this in my app? Is it better to implement this in my app or launch Handle.exe as subprocess and parse output? I briefly searched WinAPI docs and didn't found how to implement this...  For me it's not a problem to have an additional .exe file in the app folder. Main goal - everything should work fine on all Windows version since WinXP.  P.S. Seems that this is very easy task in python  ))


The joint density of the max and min of two independent exponentials

Let $X=\min(S,T)$ and $Y=\max(S,T)$ for independent exponential variables $S$ and $T$. Find the joint density of $X$ and $Y$. Are $X$ and $Y$ independent? How would you suggest I approach this?


How to install latest IPython in Ubuntu 16.04?

I want to install ipython with latest version 6.X   I used command pip install ipython, but after it installed successfully, I typed ipython in terminal then it said "ipython is not currently installed" Then I installed it using sudo apt-get insatall ipython and checked the version using ipython --version: it shows 2.4.1.   So, how can I get ipython with latest version?


I want to write in hindi in latex  मेरे माता और पिता को समर्पित|  I am using devanagri package and I want to put this in the document using the command {\dn .............}. If somebody can translate the above lines in Devanagari then i can put these in in the blank and get it to work. Also, if there i a tool readily available like google translate, it will be helpful if someone can point out


Let ${{E_n}}_{n\in \mathbb{N}}$ be a sequence such that every $E_n$ is countable.  Let $g_n : \mathbb{N} \to E_n$ be a bijection for every $n\in \mathbb{N}$.  Let $\alpha (n,k) = g_n(k)$  Let $A$ be the union of $E_n$'s.  Then $\alpha : \mathbb{N} × \mathbb{N} \to A$ is a surjective function.  Since $\mathbb{N} \times \mathbb{N}$ is equipotent with $\mathbb{N}$, there exists a surjective function $f: \mathbb{N}\to A$.  Let $[n]$={$m\in \mathbb{N}$|$f(m)=f(n)$} for every $n\in \mathbb{N}$.  Since $f$ is surjective, for every $n\in \mathbb{N}$, $[n]\ne \emptyset$.  Since $[n] \subset \mathbb{N}$, $[n]$ is well-ordered.  Let $l_n$ designate the least element of $[n]$.  Let $B=\{l_n \in \mathbb{N} | n\in \mathbb{N}\}$  Then $f_{[B]}$ : $B\to A$ is a bijection.  Since $B\subset \mathbb{N}$, $B$ is at most countable. Since $A$ is infinite, $B$ is countable, hence $A$ is countable.  I don't know where i used AC in my argument. Help