I modified my bashrc via terminal and now when I open a terminal I can not do nothing either via Ctrl+Alt+F1, Can anyone help me to fix this. In both cases appears this:   # ~/.bashrc: executed by bash(1) for non-login shells. # see /usr/share/doc/bash/examples/startup-files (in the package bash-doc) # for examples  # If not running interactively, don't do anything case $- in     *i*) ;;       *) return;; esac  # don't put duplicate lines or lines starting with space in the history. # See bash(1) for more options HISTCONTROL=ignoreboth  # append to the history file, don't overwrite it shopt -s histappend  # for setting history length see HISTSIZE and HISTFILESIZE in bash(1) HISTSIZE=1000 HISTFILESIZE=2000  # check the window size after each command and, if necessary, # update the values of LINES and COLUMNS. shopt -s checkwinsize  # If set, the pattern "**" used in a pathname expansion context will # match all files and zero or more directories and subdirectories. #shopt -s globstar  # make less more friendly for non-text input files, see lesspipe(1) [ -x /usr/bin/lesspipe ] && eval "$(SHELL=/bin/sh lesspipe)"  # set variable identifying the chroot you work in (used in the prompt below) if [ -z "${debian_chroot:-}" ] && [ -r /etc/debian_chroot ]; then     debian_chroot=$(cat /etc/debian_chroot) fi  # set a fancy prompt (non-color, unless we know we "want" color) case "$TERM" in     xterm-color|*-256color) color_prompt=yes;; esac  # uncomment for a colored prompt, if the terminal has the capability; turned # off by default to not distract the user: the focus in a terminal window # should be on the output of commands, not on the prompt #force_color_prompt=yes  if [ -n "$force_color_prompt" ]; then     if [ -x /usr/bin/tput ] && tput setaf 1 >&/dev/null; then     # We have color support; assume it's compliant with Ecma-48     # (ISO/IEC-6429). (Lack of such support is extremely rare, and such     # a case would tend to support setf rather than setaf.)     color_prompt=yes     else     color_prompt=     fi fi  if [ "$color_prompt" = yes ]; then     PS1='${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ ' else     PS1='${debian_chroot:+($debian_chroot)}\u@\h:\w\$ ' fi unset color_prompt force_color_prompt  # If this is an xterm set the title to user@host:dir case "$TERM" in xterm*|rxvt*)     PS1="\[\e]0;${debian_chroot:+($debian_chroot)}\u@\h: \w\a\]$PS1"     ;; *)     ;; esac  # enable color support of ls and also add handy aliases if [ -x /usr/bin/dircolors ]; then     test -r ~/.dircolors && eval "$(dircolors -b ~/.dircolors)" || eval "$(dircolors -b)"     alias ls='ls --color=auto'     #alias dir='dir --color=auto'     #alias vdir='vdir --color=auto'      alias grep='grep --color=auto'     alias fgrep='fgrep --color=auto'     alias egrep='egrep --color=auto' fi  # colored GCC warnings and errors #export GCC_COLORS='error=01;31:warning=01;35:note=01;36:caret=01;32:locus=01:quote=01'  # some more ls aliases alias ll='ls -alF' alias la='ls -A' alias l='ls -CF'  # Add an "alert" alias for long running commands.  Use like so: #   sleep 10; alert alias alert='notify-send --urgency=low -i "$([ $? = 0 ] && echo terminal || echo error)" "$(history|tail -n1|sed -e '\''s/^\s*[0-9]\+\s*//;s/[;&|]\s*alert$//'\'')"'  # Alias definitions. # You may want to put all your additions into a separate file like # ~/.bash_aliases, instead of adding them here directly. # See /usr/share/doc/bash-doc/examples in the bash-doc package.  if [ -f ~/.bash_aliases ]; then     . ~/.bash_aliases fi  # enable programmable completion features (you don't need to enable # this, if it's already enabled in /etc/bash.bashrc and /etc/profile # sources /etc/bash.bashrc). if ! shopt -oq posix; then   if [ -f /usr/share/bash-completion/bash_completion ]; then     . /usr/share/bash-completion/bash_completion   elif [ -f /etc/bash_completion ]; then     . /etc/bash_completion   fi fi

I've been trying to install Android developer tools on Eclipse, and I followed the information in .  Like the video said, I added the following two lines of code to the .bashrc file:  export PATH=$(PATH):-/android-sdk/tools/ export PATH=$(PATH):-/android-sdk/platform-tools/   It seems, however, that this did not help me to install the Android files on Eclipse, as I am still having problems with that. What's more, it seems that I can't make any command in the terminal without getting a major error now! Every time I try to make a command in the terminal I get the following message:     The command could not be located because '/usr/bin' is not included in   the PATH environment variable.   Is there away to restore .bashrc to its default?


• Janice used too many ‘do’s and ‘don't’s in her last paragraph.  The sentence above means that she used the individual words ‘do’ and ‘don't’ excessively in her paragraph. Without recasting and without using italics, do ‘do’s and ‘don't’s look correctly punctuated, i.e., curly single quotes around each word and a single straight quote in ‘don'ts’?  • Janice used the phrase ‘do's and don'ts’ several times in her last paragraph.  Does ‘do's and don'ts’, with the curly quotes before and after the phrase, and the straight quote in ‘don't’ look correct?  A very simple ‘yes’ or ‘no’ is fine for each question. Again, I prefer single quotes around the words/phrases in question, and I opt for not italicizing.  I think I have satisfactorily punctuated each but am looking for confirmation that I did.  Again, please no recasts.  Many thanks.

If I want to mention the word "furlong", for example, should I use furlong, "furlong", or 'furlong'? Also, am I correct in putting the punctuation outside the quotes?


I find it very annoying that one needs to explicitly inform TeX about matched parenthesis with \left and \right. Is there a clean and elegant way to make it the default? I guess I should be forced to inform TeX whenever the parenthesis are not matched, and not the other way around!  I guess the if one writes f(x), the correct (in a sense) should be f\left(x\right). In my humble and inexperienced opinion, we should write f(\int x^2) without \left and \right. And if someone intentionally does not want this behaviour s/he should say f\unmatched(\int x^2\unmatched).    Edit: I am not talking about typography. I am talking about semantics. I guess TeX mixes up those two concepts. For example David's answer to the  just says that \left and \right implementation are, in a sense, broken.  Whenever it is important for typographical decisions to know the intended semantics, I think the user should be required to explicitly state it. Otherwise, the only reason I see for not letting the typography expert (not me) decide is the fact that implementation is too hard to be done or fundamentally broken to be adapted/fixed.  For the typographic enthusiast, I would recommend TeX to make good decisions and letting the typography professional fine tune at the end. It seems important to notice that the more "fine tunes" you have, the more rigid is your project, in the sense that changing the contents a little might imply all the "fine tune" work to be undone and redone.  I don't think most of people care about how the implementation of \left and \right is done internally. I guess they want to tell the typography professional that those two parenthesis are to be matched.

Is it possible to automatically "add" \left and \right commands in front of all brackets? The source code should be left intact, but LaTeX should interpret every pair of brackets as if they were preceded by such commands. This is because adding \left and \right commands is time consuming and makes source code longer and less readable. I considered defining new commands such as \lb and \rb for \left( and \right), but it doesn't seem very elegant to me: what if I also want to add square brackets for example?  Any ideas? Thanks.


I have a problem, something I'm sure a lot of video sharing companies might have. I want to start a small business by offering online video-based training courses on Microsoft Office and other office software in my town on my native language. The problem is, I'm planning to start offering cheap suscriptions for all-access to all the videos, maybe $for 5 dollars a month to get more people interested...however, I know my target audience, and I'm sure they will quickly resort to wanting to download the videos to stop paying, and who knows, maybe even share them on some site and make them public ruining my business...  My question is, is there a video format, or a way to embed, I don't know, a video file so that it cannot be downloaded for offline playback? Maybe using flash files in some remote server? I don't know...I just need a way to play videos on a web browser, that won't allow any form of downloading for offline playback and distribution. Please help guys, I'm kid of struggling to make enough money to pay for college already.  [edit] Thanks for all the information everyone...It seems there is no right answer for this, so let me rephrase the problem.   I'm going to be dealing with people with little to no knowledge of advanced computer usage. My target audience consists of 18-23 year old college students that only use their computers for Facebook, playing candy crush, watching youtube videos and doing their homework. I know most of them are now aware of how to download videos from the internet, but their knowledge is very limited (and by that, I mean sites like KEEPVID.COM or youtube-mp3.org). Most don't even know screen capture software exists, or how to get it, so I'm hoping to use that "naive" characteristic to some use.   So ok. I CAN'T stop my videos from being downloaded, but is there a way to, as I said, make it harder, say...stop sites that download the actual video file hosted/embedded? I don't mind if you can still download the video with some tricks, I just wan't my target audience to have a hard time figuring it out. Right answer goes to the most useful answer, since there is no right answer.

Is there a license / royalty free DRM available for protecting and distributing video content?


I have to compute $\text{Var}(\min(X,Y) \max(X,Y))$, where $X$ and $Y$ have uniform distribution on $[0,1]$. I calculated $E(\min(X, Y))$ and $E(\max(X, Y))$, but I do not know how to calculate $E(\min(X, Y) \cdot \max(X, Y))$.  Thanks in advance.

I'm looking for someone to walk me through how to solve E[ZW] if Z = max[X,Y] & W = min[X,Y]. X & Y are independent, uniform variables over the interval [0,1].  I solved E[Z] = 2/3 and E[W] = 1/3.   E[ZW] should equal 1/4 but I keep getting the wrong answer. I have searched the forums and used other people's answers to try and solve it but have gotten the incorrect numbers.  Thank you in advance!


Let's assume someone has a very thorough knowledge of a particular field of science but they have absolutely no formal education in this background.  This individual one day realizes a very novel approach to solving a somewhat complex problem.  After developing independent tests and coming up with rock-solid evidence that her method is groundbreaking, and consistently produces test results that would be impossible without a legitimate solution, what can she do with her research to both share the information with the world and retain some form of credit for the discovery?  In other words, how can one be both a hobbyist contributing to a field of scientific study and yet also retain the respect they deserve for their work if it is of great use and benefit?  To be clear, this isn't about having one's name appear in a Science Journal without the necessary credentials.  I think it's respectable to maintain certain sets of rules and standards for journalistic publications.  However, it also isn't fair for such a person to have to divulge this information to someone who is "qualified" and have them receive all or most of the credit for someone elses work, just because that other person hasn't earned a piece of paper.  How can hobbyist both share, and maintain, the recognition they deserve if they make a legitimate scientific breakthrough?

Assume you have already completed your undergrad and have been working for a number of years. Does one need to be part of a university or a learning institution to publish papers?


How to make from this:  [[1, 0, 0], [1, 0, 0], [1, 0, 0], [1, 0, 1], [1, 0, 1], [1, 0, 1]]   to this?  array([[1, 0, 0],        [1, 0, 1]])   I tried this but it only works with 2 repeated elements. I want it to work for any number of repeated elements.  finalRes = []  for i in range(len(resList)-1):     if resList[i] == resList[i+1]:         finalRes.append(resList[i])  finalRes --> [[1, 0, 0], [1, 0, 0], [1, 0, 1], [1, 0, 1]]

Is there a built-in that removes duplicates from list in Python, whilst preserving order? I know that I can use a set to remove duplicates, but that destroys the original order. I also know that I can roll my own like this:  def uniq(input):   output = []   for x in input:     if x not in output:       output.append(x)   return output   (Thanks to  for that .)  But I'd like to avail myself of a built-in or a more Pythonic idiom if possible.  Related question:


We have this phrase that aims to communicate that after an organization is selected, the table is shown but also the button as well.     The table and button are shown after an organization is selected.   Wouldn't it sound better to include "the" like:     The table and the button are shown after an organization is selected.   Is there a rule or something to generalize its correct use?

It seems that the question has eventually become a series of questions....    An example goes as:     The 1st and (the) 2nd paragraphs of the article are extremely long.   Another example:     What are the situation, (the) task and (the) result of your story?   Is it necessary to use the in ()?


I wrote a template class for a Singleton singleton.cpp: template<typename T> class Singleton {    protected:     Singleton() = default;    public:     virtual ~Singleton() = default;     Singleton(const Singleton<T>&) = delete;    public:     Singleton& operator=(const Singleton&) = delete;    public:     static T& GetInstance() {       static T instance;        return instance;     }  }  And my logger class inherits this template class Logger : public Singleton<Logger> {    private:     Logger();    public:     ~Logger; }  but when i call Application::GetInstance() I get an undefined reference undefined reference to `Singleton<Application>::GetInstance()

Quote from :     The only portable way of using templates at the moment is to implement them in header files by using inline functions.   Why is this?  (Clarification: header files are not the only portable solution. But they are the most convenient portable solution.)


With the new Tasha's Cauldron of Everything feat Metamagic Adept, warlocks get access to Subtle Spell. Can Subtle Spell be used in conjunction with a chain warlock's familiar to cast, say, death ward at range without someone knowing?

I have recently created a  (XGtE, p. 50) and plan on taking the  feat (PHB, p. 168) where my lvl 1 spell would be . Now as it states this familiar can be a focal point for your touch spells (like  for me).  Can I apply metamagic options to spells delivered through the familiar?  For example: My familiar is close to 2 of my allies. Can I at this point make it cast a twinned death ward to make both my allies warded?


How can I upgrade my Ubuntu version to 13.10. My current Ubuntu version is 13.04.

What are the different ways I can use to upgrade Ubuntu from one release to another?


i recently downloaded ubuntu and after installing it and rebooting it the computer tells me windows failed to laod components have been erased or missing and insert your installation disk and press repair  so what do i do is there another way out of this problem i currently run windows 8 os on a hp pavilion with a a4 amd processor at 2500 mhz and i downloaded and installed the 32 bit version of ubuntu linux? please help if I have to buy the installation disk I will but I want to know if there are any other options.

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


The Narzugon's Hellfire Lance states:     Hellfire Lance. Melee Weapon Attack: +10 to hit, reach 10 ft., one target. Hit: 11 (1d12 + 5) piercing damage plus 16 (3d10) fire damage. If this damage kills a creature, the creature's soul rises from the River Styx as a lemure in Avernus in 1d4 hours. If the creature isn't revived before then, only a wish spell or killing the lemure and casting true resurrection on the creature's original body can restore it to life. Constructs and devils are immune to this effect.   Notably, this wording is different from "if this damage reduces a creature to 0 hit points" effects.   When is the Lance's damage considered to have "killed a creature"?  A few situations I can think of (intended as illustrative examples of boundary cases, I'm not expecting an answer to address all of these):   If the lance's damage renders the creature unconscious, and they then fail 3 death saves without taking further damage If the lance causes a creature to fail its last death save If something other than the lance's damage rendered a creature unconscious, but then an attack from the lance causes the creature to fail 1-2 death saves, and they fail the last one naturally If the lance's damage rendered a creature unconscious, but then damage from another source causes the creature to fail two death saves, and they fail the last one naturally If the lance caused massive damage to a creature, killing them instantly

says:     A humanoid killed by this spell rises at the start of your next turn as a zombie that is permanently under your command   If a player is hit by finger of death and dropped to 0hp, do they turn into a zombie immediately? If they subsequently fail death saves and die, do they then turn into a zombie?


Today I started the Terminal and the prompt showed:  flos-ipad: mareek$   Now I'm confused because this is not the Hostname of my MacBook Pro. Furthermore my name isn't "Flo" and I don't own an iPad. The Username "mareek" is correct for the user I'm logged in to.  I tried  $ scutil --get HostName HostName: not set $ scutil --get LocalHostName Macbook-Pro-2 $ scutil --get ComputerName Macbook-Pro   I wonder why the Hostname isn't set, and where the "flos-ipad" comes from? Any ideas?  Thank you  EDIT: I actually found the solution.  /close

For three days straight, I have connected to the public WiFi network at my local library. Each day, I have seen a different prompt in Terminal. Here are some of the prompts I've seen:  zp-pc:~ russell$ mary-pc:~ russell$ normob05:~ russell$   I have check under System Preferences -> Sharing, and my computer name is "Russell's Mac". Also, I set the DHCP Client ID to "RUSSMAC" under System Preferences -> Network -> Advanced -> TCP/IP, but I still see the random host names at the Terminal prompt.  Why is my computer name changing every day?


Prove that all the roots of the equation $(1+z)^6+z^6=0$ are collinear.    $(1+z)^6+z^6=0$ $\frac{1+z}{z}=(-1)^{1/6}=e^{i\pi/6},e^{i3\pi/6},e^{i5\pi/6},e^{i7\pi/6},e^{i9\pi/6},e^{11i\pi/6}$,but i do not know how to solve further.

The complex roots of the equation      $$z^{n}=(1+z)^{n}$$   $A.$ are vertices of a regular polygon  $B.$ lie on a circle  $C.$ are collinear  $D.$ none of these  Don't know where to start.. Please help.!  NOTE:  $z$ is a complex number.


I have the code below which is a logical expression and should return TRUE. However, it returns FALSE! Any idea why? and how to fix it?  ((1.1 - 1)*100) <= 10

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


The story peripherally involves a corporation named Eight Colors, but also includes a plot about people living underground, viewing the surface through prisms and periscopes. Near the end the protagonist takes a group of people to the underground community, where they are psychoanalyzed, and their emotions are encoded on shifting color badges they wear on their shirts or sleeves, i.e., literally wearing their feelings on their sleeves.

I don't know a lot about the plot of this book as it has been quite a while since I last read it. But I do now that it was set in the space age, where everybody could travel between planets. It also had something to do with searching an mysterious, indescribable color (the 8th?).    There were aliens that were not able to perceive color who maintained the spaceships. A characteristic I can quite clearly remember is that these aliens (called lhari/laari?) would often get burned when they picked up a glowing tool, as the couldn't see it glowing.    At some point the protagonist undergoes a surgery to look like these aliens to do something they wouldn't allow humans to do. Maybe travel somewhere or spy on them?    I read it maybe 4 years ago, but it was an old book I picked up at a garage sale. I cannot name a specific time when it was written, but my best guess would be 1970-1980.   If I happen to remember more things, I will make sure to edit this question.


Let $X=\{1,2,3,...,25\}$. If a student selects a function randomly from the set of all functions from $X$ onto $X$,then what is the probability that the selected function maps prime numbers to prime numbers? please reply in factorial format no need to open the factorials

Let $X = \{1, 2, 3, . . . , 25\}$. If a student selects a function randomly from the set of all functions from $X$ onto $X$, then what is the probability that the selected function maps prime numbers to prime numbers ? No idea how to proceed, please guide.


I would like to maximize all my app windows, especially browser windows. But I don't want to cover up the Menu bar at the top of the screen.  Right now, when I maximize Google Chrome for instance, it will expand all the way and hide the Menu bar, but when I hover the mouse pointer to the top, the window will jump up and down to reveal/conceal the Menu bar. I find this to be super annoying.  The first step of the dance routine:    The second step of the dance routine:    And, as I move my mouse up/down the view will toggle. I just want the Menu bar to always remain visible, but for my app windows to be maximized. Is that so hard?

I'm new to macOS and I really like the way you can assign a window to be it's own Desktop via full-screening. However, I have an issue with the default way the Menu bar works in full-screen.   I often move my cursor to the top of the screen to click on my tabs in my browsers and editors, and accidentally trigger the Menu bar obscuring my tabs. Other times I'd like the Menu bar to be available at a glance rather than having to trigger it by mousing up.  Is there some setting or application that will force the Menu bar to show at all times for full-screened windows?  It appears I'm not the first to have this issue, but the solutions in  didn't work for me and based on the comment for the top answer it won't work for anyone.  If there is no way to do this can anyone give me a hint where I can get started writing an application to do this?  PS: Please don't suggest that I simply hold alt when clicking the fullscreen green button or anything else like just resize the window to fill the screen". This doesn't solve my issue because it strips away many of the advantages of fullscreening.


The Chinese embassy in Australia publishes a  regarding acceptable passport photos.  They vary subtly but distinctly from the rules for  in Australia: for example, the photo must be 33x48mm (vs min. 35x45mm), height of head must be 28-33mm (vs 32-36 mm), etc.  In practice, are regular 35x45mm Australian passport photos accepted?  Or do I really need to go get a separate set just for this?

The Chinese government has a really specific list of requirements for visa photos:    I had an old unused photo from last time I applied for a visa or passport, and compared it to the requirements (decided not to use it because it was damaged). It seemed to match most of the requirements, except that it seems that they want a photo which isn't square: The required width is less than the required height.  Assuming most drugstores are still providing square passport photos, the question becomes: Should I cut the photo to match the specified width?   What adds to the confusion is if you look at the  the box for the photo is nearly square, not the oblong shape in the requirements. And I have seen other advice that you need to make sure it fully fits the box.  Any advice about what to do here?


I have a problem. My lecturer gave the task to make an article with LaTeX. but in one condition,  I can't set the picture like this. How to set a picture like this in LaTeX?

How to wrap text around a figure in LaTeX like this?  Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean quis mi ut elit interdum imperdiet quis non ante. Sed imperdiet, sapien quis    +------------------------+ viverra rhoncus, tellus dui   |                        | dictum nisl, at porta purus   |                        | ipsum ac turpis. Fusce auctor |         FIGURE         | ullamcorper adipiscing. Nunc  |          HERE          | non quam ac orci egestas con- |                        | sequat ut eget quam. Cras     |                        | blandit condimentum ornare.   +------------------------+ Curabitur aliquam, nulla sit amet iaculis tristique, mi nulla auctor magna, sit amet imperdiet ante arcu a libero.


Here is a sample question paper. I want to extract questions, their options and diagrams for the corresponding question(if any). Thinking of doing entity recogntion for the same. But I am not sure if that is possible for diagrams? Can someone help me out. I tried OCR techniques previously but they are not doing well.

This is the sample document ->  I want to extract questions along with the options. There are other question papers as which have questions with diagrams in them. I want to be able to extract them as well. End goal is to store them in a question bank. I am planning to run an image segmentation algorithm to extract the questions along with their options. Will that be feasible? Suggestions are more than welcome.


In the following example, I'm using a minipage that should span the entire text area.   \documentclass[parskip]{scrartcl}  \setlength{\overfullrule}{10pt}  \begin{document}   before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before before  \begin{minipage}[t]{\textwidth} inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside inside \end{minipage}  after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after after   \end{document}   While this works, it also generates a warning (Overfull \hbox (10.95003pt too wide) in paragraph at lines 11--16).    There are already numerous answers to similar problems, but none of the solutions I've tried so far seem to apply here. I'm using the parsnip option, so I understand that a before the minipage environment does not change anything. I've tried to , to no avail. If I reduce the width of the minipage to 0.97\textwidth, the warning disappears, but the minipage text is visibly narrower than the rest of the surrounding text. What is causing the warning in this case?

When I use the tcolorbox package with the KOMA-option parskip=half, I get the error Overfull \hbox every time I use a tcolorbox. This warning appears despite the fit warning=false option of the box.  Everything looks fine, so it's not a big issue, but it's really annoying and "real" warnings get lost between these ones in long documents.  MWE:  \documentclass[parskip=half]{scrartcl}  \usepackage{tcolorbox}  \begin{document}  \begin{tcolorbox}     foo \end{tcolorbox}  \end{document}   (fit warning=false is set by default.)


If there was a pole, that was a light year long, out in space. (Away from all physical interference.)  If we pushed one end of it, would the other end move instantly? And does it's speed depend on what it's made of?

Is it possible for information (like 1 and 0s) to be transmitted faster than light?   For instance, take a rigid pole of several AU in length. Now say you have a person on each end, and one of them starts pulling and pushing on his/her end.   The person on the opposite end should receive the pushes and pulls instantaneously as no particle is making the full journey.  Would this actually work?


None of the NPCs will move in, is it because of the ore? The building I have right next to it had a NPC in it already and now it is vacant. Is this also because of the ore?

I read on the wiki that people will move in under the following conditions:   You do something to please them An empty house is available with a light source, table, and chair (also with walls).   I have a house which is about 7x8, then a roof space above that; about half the area. I could put furniture up there too, but will anyone move in?


I want to show '\' in final pdf file, not as a command to latex, but as a text '\' itself. How can I do this?

How does one insert a "\" (backslash) into the text of a LaTeX document? And how does one insert a "~" (tilde)? (If you insert \~, it will give you a tilde as an accent over the following letter.)    I believe \backslash may be used in math formulae, but not into text itself. Lamport's, Kopka's, and Mittelbach's texts have said as much (but no more), and so left me hanging on how to get a backslash into regular text.


I was wondering if there exists a pair of natural numbers $n, m \in \mathbb{N}$, such that $e^n = m$? Of course excluding the simple solution (0,1). Intuitively, I would say no. However, I am far from finding an argument, nor knowing which theory even treats these types of questions. Cheers

May $y=e^x$ be satisfied with both $x$ and $y$ be positive integers?  I think it is not possible as $e$ ,a transcendental number, when multiplied by itself would never result in rational number.  Am I right?


If someone wants to know what the time limit is for acceptances, they need to come here and search in the . That's suboptimal - not everyone even knows about the existence of main meta, and this sort of vital info should be self-contained on a given site and its help centre.  The logical place to look would be in the  page in the help centre, but the info isn't there.  Please could info about allowed times for acceptances be included in the help centre?  Another short paragraph to say this would be great:     You can only accept an answer after 15 minutes have elapsed from the time you posted the question. This time limit is raised to 48 hours if the answer is your own.

I noticed that I can only perform certain actions such as commenting a finite number of times in a given period of time. Obviously, rate limiting is in place to prevent accidental misuse or intentional abuse of certain features.  Where else is rate limiting applied on Stack Exchange sites, and what are the limits?


Heres a picture. im making a body, and it seems to have flash in the middle.

When I add a mirror modifier it sometimes doesn't mirror correctly, giving me an overlapping mesh. How can I fix this?


Should I use the <img> tag or should I use a div with css background-image?

In what situations is it more appropriate to use an HTML IMG tag to display an image, as opposed to a CSS background-image, and vice-versa?  Factors may include accessibility, browser support, dynamic content, or any kind of technical limits or usability principles.


I am travelling to the USA with KLM and my routing is as follows:  BOM - CDG - AMS - ORD.  Do I require a Schengen visa (Airport Transit etc)?  My ticket is a single ticket and all connections are within 2 hours.  Please help.

I found many related questions on this site but I am still not sure about the rules. How can I decide if I need a visa to transit? Schengen members as of May 2021 are as follows:  Austria Belgium Czech Republic Denmark (excluding Greenland and the Faroe Islands - but an open border with the Schengen Area is maintained) Estonia Finland France (excluding overseas departments and collectivities) Germany Greece Hungary Iceland Italy Latvia Liechtenstein Lithuania Luxembourg Malta Netherlands (excluding Aruba, Curaçao, Sint Maarten and the Caribbean Netherlands) Norway (excluding Svalbard) Poland Portugal Slovakia Slovenia Spain (except Ceuta and Melilla) Sweden Switzerland


Title says it all, really. Just rewatched the trilogy and I really don't understand why they needed Neo's help to deal with Smith.

Towards the end in The Matrix Revolutions, Neo is jacked by the machines into the Matrix to fight Agent Smith. During the fight, Smith seems to have killed Neo then we see the machines pumping a charge into Neo to revive him. Neo however doesn't seem to be active inside the Matrix anymore and just explodes into light.  We then see his physical form being set down by the machines. Is Neo at this point actually dead or is he just unconscious?


DATA: ,    Hi all!  I'm looking to perform what I've been taught is called a spatial join. After researching this further, it's looking like this operation is most often called a table join. So sorry for any confusion in the wording!  What I want to accomplish is very straightforward. I have a CSV that contains data for admin boundaries in the Philippines. I have a shapefile of said admin boundaries. I want to join these together in R to make choropleth maps. Easy enough, right?  To do this in QGIS, I simply add the shapefile and CSV as layers. Within the shapefile, Properties -> Joins, then add the join from there. Here's a screenshot for the sake of complete clarity:   As you can see, the Admin category of the CSV file matches the REGION category of the shapefile's attributes. Once those are joined, I am easily able to create choropleth maps from any of the other attributes from the CSV. Quick dummy-proof example here:   Now how the heck do I do this in R? It seems like it should be really easy to do, but I can't find much information, as all of my queries have yielded results of spatial joins concerning "join attributes by location" from data management tools in QGIS. I am not trying to find out which points fall within x polygons. I simply need to join the CSV to the shapefile so that I can make a choropleth map!   seems most similar to what I'm asking, but I couldn't sift through it enough to make sense of what I needed out of it.

I wanted to join a CSV file to a shapefile.  When I identified a field to facilitate the join, e.g.,   map <- spChFIDs(map, as.character(map$ID))   it returned     Error in spChFIDs(SP, x) : lengths differ   Can anyone advise?


I understand the Cantor's proof for why $S<2^S$, but also we know that ordinals $\omega\sim\omega^2\sim\omega^3...$. This approaches to $\omega^{\omega}$, what should be at least not less than $2^{\omega}$. What do I miss with this logic?

As we know, $2^{\aleph_0}$ is a cardinal number, so it is a limit ordinal number. However, it must not be $2^\omega$, since $2^\omega=\sup\{2^\alpha|\alpha<\omega\}=\omega=\aleph_0<2^{\aleph_0}$, and even not be $\sum_{i = n<\omega}^{0}\omega^i\cdot a_i$ where $\forall i \le n[a_i \in \omega]$. Since $\|\sum_{i = n<\omega}^{0}\omega^i\cdot a_i\| \le \aleph_0$ for all of them.  Besides, $\sup\{\sum_{i = n<\omega}^{0}\omega^i\cdot a_i|\forall i \le n(a_i \in \omega)\}=\omega^\omega$, and $\|\omega^\omega\|=2^{\aleph_0}$ since every element in there can be wrote as $\sum_{i = n<\omega}^{0}\omega^i\cdot a_i$ where $\forall i \le n[a_i \in \omega]$ and actually $\aleph_{0}^{\aleph_0}=2^{\aleph_0}$ many.   Therefore $\omega^\omega$ is the least ordinal number such that has cardinality $2^{\aleph_0}$, and all ordinal numbers below it has at most cardinality $\aleph_0$. Hence $\omega^\omega=2^{\aleph_0}=\aleph_1$?


Let $X\subset\mathbb{A}^{n},Y\subset\mathbb{A}^{m}$ be affine varieties over $k$ algebraically closed. Then, $X\times Y\subset \mathbb{A}^{m+n}$ may be checked to be an affine variety as well; furthermore, it's just the product in the category of varieties. Then, because the functor $A(-)$ is an arrow-reversing equivalence of categories, it follows that $A(X\times Y)=A(X)\otimes_{k} A(Y)$, as tensor product is the coproduct in the category of finitely generated $k$-algebras which are domains.  Unless I have made a mistake, one can check directly from the universal property of tensor product that we also have \begin{equation*} k[x_{1},\ldots,x_{n}]/I(X)\otimes_{k}k[y_{1},\ldots,y_{m}]/I(Y)=k[x_{1},\ldots,x_{m},y_{1},\ldots,y_{m}]/(I(X)+I(Y)), \end{equation*}  and of course $I(X)+I(Y)\subset I(X\times Y)$, so it should be true that we in fact have equality $I(X)+I(Y)=I(X\times Y)$. Is there a direct way to see this? In particular, it seems like it should be true for arbitrary Zariski-closed $X,Y$.  (Source: Hartshorne, Exercise I.3.15)

This is a follow up question to my previous question  Let $k$ be a field and $V \subseteq \Bbb{A}^n$ and $W \subseteq \Bbb{A}^m$ be algebraic sets. Then it should be true that $I(V \times W ) = I(V) + I(W)$ where by $I(V)$ here we mean the extension of $I(V)k[x_1,\ldots,x_{m+n}]$. Now I believe I have proven this (see the proof at the bottom of my question) but when I look at Martin's answer , it is instead claimed that we  actually have  $$I(V \times W )= \sqrt{I(V) + I(W)},$$  and for $I(V) + I(W)$ to be a radical ideal we need $k$ to be algebraically closed.           My question is: What's going on here? I believe my claim is true even without the assumption that $k$ is algebraically closed.           Here's a proof user Sanchez told me of, which I have simplified:       First it is clear that we always have $I(V) + I(W) \subseteq I(V \times W)$. For the reverse inclusion consider a polynomial $f \in I(V \times W)$. Then we can always write $$f = \sum_{i=1}^n f_ig_i$$ where $f_i \in k[x_1,\ldots,x_n]$ and $g_i \in k[x_{n+1},\ldots,x_{m+n}]$. Now take any $b' \in W$. If for all $i$ we have $g_i(b') = 0$ then since $b'$ is arbitrary, $g_i \in I(W)$ for all $i$. Then $f \in I(W) \subseteq I(V ) + I(w)$ and we are done. Otherwise suppose there exists $b \in W$  and $i$ such that $g_i(b) \neq 0$. Then wlog we may suppose that  $g_1(b) \neq 0$.   Next, $\sum f_ig_i(b) = 0 $ on all of $V$ by assumption of $f \in I(V \times W)$. So $\sum f_i g_i(b) = p$ for some $p \in I(V)$. Now write $$f_1 = \frac{ p - g_2(b) f_2 + \ldots g_n(b)f_n}{g_1(b)}.$$  Substituting this for $f_1$ in $\sum f_ig_i$, followed by taking things mod $I(V)$ we get an  expression with only $n-1$ terms $\mod{I(V)}$. Continuing this process we will finally get an expression with $0$ terms $\mod{I(V)}$ so that $f \in I(V)$. This shows $I(V \times W) \subseteq I(V) + I(W)$ which completes the proof.


How can I remove weird Â characters from my output without needing to edit hundreds of rows in MySQL.  Data is being read from a MySQL database and outputted to the browser via HTML.

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


I'm trying to proof that when dividing the first series with $p$, the remainder is $p-1$ and when dividing the second series with $p$ ($p>2$) the remainder is $0$. I understand that I need to use Fermat's little theorem, and maybe the special case of it, but have problems applying it. And help of hints would be superb as I seem to be stuck...   David

Show that    $$1^{p-1} + 2^{p-1} +\ldots + (p-1)^{p-1} \equiv -1 \mod p$$   So, I use Fermat's little theorem, that is if $p$ does not divide $a$, then $a^{p-1}$ is congruent to $1$ (mod $p$). But I'm still confused. If $1^{p-1}$ is congruent to $1$ (mod $p$), $2^{p-1}$ is congruent to $1$ (mod $p$), and $p$ does not divide $p-1$, so $(p-1)^{p-1}$ is congruent to $1$ (mod $p$). How does that equal $-1$ (mod $p$)?


Please explain the differences between using 'will' and 'would' in the examples below:     There is a possibility he would win.   Versus     There is a possibility he will win.   And      There is still a chance that he will arrive before 7.   Versus     There is still a chance that he would arrive before 7.   Both are very common but my take on it is that "will” suggests a much stronger/greater probability or future likelihood compared to "would".  Please offer yours.

Most people say I wish I could, I wish you would.    Can we use I wish I can, I wish you will?    I'd like to know what the main differences between the usage of can/will and could/would are when wishing.  Is it related to the subjunctive? Because one says “I wish I were”, not “I wish I am”, so are would and could the subjunctive forms of can and will?  Or is it something else entirely?


I´m creating a new bibliography style by customizing the standard.bbx file for my master thesis. So far I had no big troubles but now I want to adjust the macro series number since this should be in parentheses. Due to the lack of information I somtimes only have a seriesor the number.   So far it works out well, unless I only have the series. Then a space between the last word of the series and the closing parentheses appeares.  Here is my new macro  \newbibmacro*{series+number}{%     \iffieldundef{series}% Überprüfen ob series vorhanden         {}         {   \setunit{\addspace\bibopenparen}             \printtext{Reihe \addcolon\space}%             \printfield{series}             \iffieldundef{number} % Überprüfen ob noch Bd kommt                 {\printtext{\bibcloseparen}}                 {\setunit{\addcomma\space}}         }%     \iffieldundef{number}%         {}         {   \iffieldundef{series}%                 {\setunit{\addspace\bibopenparen}}                 {}             \printtext{Bd \adddot}             \printfield{number}%             \printtext{\bibcloseparen\space}         }   \newunit}   And here is the MWE  \RequirePackage{filecontents}  \begin{filecontents*}{my_bibfile.bib}     @incollection{Akyar.2008,         author = {Akyar, Bedia},         title = {Dual Quaternions in Spatial Kinematics in an Algebraic Sense},         pages = {373--391},         bookpagination = {page},         publisher = {T{\"u}bitak},         isbn = {1010-7622},         editor = {{Scientific and Technological Research Council of Turkey}},         booktitle = {Turkish journal of mathematics},         year = {2008},         abstract = {},         shorthand = {AKYA08},         location = {Ankara},         edition = {32},         number = {4}     }      @book{Angeles.2007,         author = {Angeles, Jorge},         year = {2007},         title = {Fundamentals of Robotic Mechanical Systems},         url = {http://site.ebrary.com/lib/alltitles/docDetail.action?docID=10229254},         edition = {Third Edition},         publisher = {{Springer Science+Business Media LLC}},         isbn = {0-387-29412-0},         subtitle = {Theory, Methods, and Algorithms},         shorthand = {ANGE07},         language = {eng},         location = {Boston, MA, USA},         series = {Mechanical Engineering Series},         abstract = {},         doi = {10.1007/978-0-387-34580-2},         file = {http://gso.gbv.de/DB=2.1/PPNSET?PPN=546653987},         file = {http://external.dandelon.com/download/attachments/dandelon/ids/DEAGI363052149B0CFDDDC125715B0045ACDA.pdf},         file = {http://zbmath.org/?q=an:1140.70001}     } \end{filecontents*}  \documentclass[fleqn]{scrreprt}  \usepackage[scaled]{helvet} \renewcommand{\familydefault}{\sfdefault}  \usepackage[T1]{fontenc}  \usepackage[utf8]{inputenc}  \usepackage[style=alphabetic, % Use this style  isbn=false, doi=false, url=false, maxbibnames = 4, minbibnames = 3, language = ngerman, giveninits=true]{biblatex}   \bibliography{my_bibfile}  \begin{document}  \nocite{*}  \printbibliography  \end{document}   The first reference only has a number (Here (Bd. 4)). The second has a series. But bevor the closing parentheses there is a unnecessary spacing.

I see that the code in many packages and examples contains percent signs % at the end of (many) lines. What are they used for? Do they affect the parsing of those lines?


Stuck on a homework question with mathematical induction, I just need some help factoring and am getting stuck.  $\displaystyle \sum_{1 \le j \le n} j^3 = \left[\frac{k(k+1)}{2}\right]^2$  The induction part is: $\displaystyle \left[\frac{k(k+1)}{2}\right]^2 +(k+1)^3$ is where I am having a problem.   If you could give me some hints as to where to go since I keep getting stuck or writing the wrong equation.   I'll get to $\displaystyle \left[{k^2+2k\over2}\right]^2 + 2{(k+1)^3\over2}$  Any push in the right direction will be appreciated.

How can I prove that     $$1^3+ 2^3 + \cdots + n^3 = \left(\frac{n(n+1)}{2}\right)^2$$    for all $n \in \mathbb{N}$? I am looking for a proof using mathematical induction.  Thanks


I have french words stored in database,however while displaying in browser the characters are not properly displayed,displays like � and so on..How convert such word exactly to french words same as entered in database using PHP ? I have tried html_entity_decode(),works for some of the cases.


Why is the electric potential on the surface of a charged metal sphere always constant?

Since the electric field inside a conductor is zero that means the potential is constant inside a conductor, which means the "inside" of a conductor is an equal potential region.   Why do books also conclude, that the surface is at the same potential as well?


I am not sure how to approach the following problem:  Show the open interval $(a,b)$ is bijective with the closed interval $[c,d]$.  I was thinking of using $a+u$ where $u$ is a really small number and $b+v$ where $v$ is a really small number to make a new interval $[a+u, b-v]$, which is equivalent to (a,b).

Recently, I answered to this problem:     Given $a<b\in \mathbb{R}$, find explicitly a bijection $f(x)$ from   $]a,b[$ to $[a,b]$.   using an "iterative construction" (see below the rule).  My question is: is it possible to solve the problem finding a less exotic function?  I mean: I know such a bijection cannot be monotone, nor globally continuous; but my $f(x)$ has a lot of jumps... Hence, can one do without so many discontinuities?    W.l.o.g. assume $a=-1$ and $b=1$ (the general case can be handled by translation and rescaling). Let:  (1) $X_0:=]-1,-\frac{1}{2}] \cup [\frac{1}{2} ,1[$, and  (2) $f_0(x):=\begin{cases}     -x-\frac{3}{2} &\text{, if } -1<x\leq -\frac{1}{2} \\ -x+\frac{3}{2} &\text{,     if } \frac{1}{2}\leq     x<1\\ 0 &\text{, otherwise} \end{cases}$,  so that the graph of $f_0(x)$ is made of two segments (parallel to the line $y=x$) and one segment laying on the $x$ axis; then define by induction:  (3) $X_{n+1}:=\frac{1}{2} X_n$, and  (4) $f_{n+1}(x):= \frac{1}{2} f_n(2 x)$  for $n\in \mathbb{N}$ (hence $X_n=\frac{1}{2^n} X_0$ and $f_n=\frac{1}{2^n} f_0(2^n x)$).  Then the function $f:]-1,1[\to \mathbb{R}$:  (5) $f(x):=\sum_{n=0}^{+\infty} f_n(x)$  is a bijection from $]-1,1[$ to $[-1,1]$.  Proof: i. First of all, note that $\{ X_n\}_{n\in \mathbb{N}}$ is a pairwise disjoint covering of $]-1,1[\setminus \{ 0\}$. Moreover the range of each $f_n(x)$ is $f_n(]-1,1[)=[-\frac{1}{2^n}, -\frac{1}{2^{n+1}}[\cup \{ 0\} \cup ]\frac{1}{2^{n+1}}, \frac{1}{2^n}]$.  ii. Let $x\in ]-1,1[$. If $x=0$, then $f(x)=0$ by (5). If $x\neq 0$, then there exists only one $\nu\in \mathbb{N}$ s.t. $x\in X_\nu$, hence $f(x)=f_\nu (x)$. Therefore $f(x)$ is well defined.  iii. By i and ii, $f(x)\lesseqgtr 0$ for $x\lesseqgtr 0$ and the range of $f(x)$ is:  $f(]-1,1[)=\bigcup_{n\in \mathbb{N}} f(]-1,1[) =[-1,1]$,  therefore $f(x)$ is surjective.  iv. On the other hand, if $x\neq y \in ]-1,1[$, then: if there exists $\nu \in \mathbb{N}$ s.t. $x,y\in X_\nu$, then $f(x)=f_\nu (x)\neq f_\nu (y)=f(y)$ (for $f_\nu (x)$ restrited to $X_\nu$ is injective); if $x\in X_\nu$ and $y\in X_\mu$, then $f(x)=f_\nu (x)\neq f_\mu(y)=f(y)$ (for the restriction of $f_\nu (x)$ to $X_\nu$ and of $f_\mu(x)$ to $X_\mu$ have disjoint ranges); finally if $x=0\neq y$, then $f(x)=0\neq f(y)$ (because of ii). Therefore $f(x)$ is injective, hence a bijection between $]-1,1[$ and $[-1,1]$. $\square$


I've tried to understand why $\displaystyle\sum_{k=0}^{\infty} \frac{k^x}{k!}$ for lets say $x = 4$ equals $15e$.  It's clear why $\displaystyle\sum_{k=0}^{\infty} \frac{x^k}{k!} = e^x$ and that $\displaystyle\sum_{k=0}^{\infty} \frac{1^k}{k!}=e$   It's also unclear for me why $\displaystyle\sum_{k=0}^{\infty} \frac{k}{k!}=e$  I've tried to argue that $\displaystyle\sum_{k=0}^{\infty} \frac{e^k}{k!}= \displaystyle\sum_{k=0}^{\infty}\frac{k}{\ln(k!)}$ but that doesn't bring me further.  Hope someone here has got an idea for me  Thanks.

How can I find the value of the sum $\sum_{k=1}^{\infty}\frac{k^n}{k!}$? for example for $n=6$, we have $$\sum_{k=1}^{\infty}\frac{k^6}{k!}=203e.$$


I was try and my macbook can charger with ipad charger (i see output 5.2v-2.4a) with usb A to C convert.  But when i read on my macbook charger, it is have 2 output : 14.5v-2.0a and 5.2v-2.4a  my macbook can charge in 2 mode (both 14.5 and 5.2) or only with 5.2v?  if only need 5.2v , why need 14.5v output ?  maybe i use ipad charger on along time, it is what problem ?

If there is only the Macbook 12 inch USB-C charger nearby, can it be used to charge other USB-C devices, such as any Android phones that also use USB-C? (will it be "too powerful" and damage other devices?)  Vice versa, if there is a Quick Charge 2.0 or 3.0 USB-C charger from other devices nearby, can it be used to charge the Macbook 12 inch?  The main concern is about whether it could damage the device or battery.


How prove the following equality for a block matrix? $$\det\left[\begin{array}[cc]\\A&C\\ 0&B\end{array}\right]=\det(A)\det(B)$$ I tried to use a proof by induction but I'm stuck. Is there a simpler method? Thanks for help.

I'm trying to prove the following: Let $A$ be a  $k\times k$ matrix, let $D$ have size $n\times n$, and $C$ have size $n\times k$. Then,  $$\det\left(\begin{array}{cc} A&0\\ C&D \end{array}\right) = \det(A)\det(D).$$  Can I just say that $AD - 0C = AD$, and I'm done?


In math lesson, my teacher told me that Euler once used a very delicate method to calculate $\displaystyle S_{n}=\sum_{i=1}^{n}\frac{1}{i^{2}}$ and wrote a paper about it.  I wonder how to calculate this. I need a precise answer, not the answer that it's less than a number such as 2.

As I have heard people did not trust Euler when he first discovered the formula (solution of the ) $$\zeta(2)=\sum_{k=1}^\infty \frac{1}{k^2}=\frac{\pi^2}{6}.$$ However, Euler was Euler and he gave other proofs.   I believe many of you know some nice proofs of this, can you please share it with us?


Dave and Sharon Sampson established a plan to save 347𝑝𝑒𝑟𝑚𝑜𝑛𝑡ℎ(𝑜𝑟4164 per year) for their children's education. Their oldest child is 5 years old and will begin college in 13 years. They will invest the $347 in a savings account that they expect will earn interest of about 4.8% a year, compounded monthly, over the next 13 years.  This was the original question. However, I was having trouble answering part part d.   d) How would their savings accumulate if they could save 198.5 bi-weekly instead of $347 per month (at 5.8% interest per year).  I am having trouble with identifying the i and n values which are required to solve the formula. Could I get some help?

Dave and Sharon Sampson established a plan to save \$347 per month (or \$4164 per year) for their children's education. Their oldest child is 5 years old and will begin college in 13 years. They will invest the \$347 in a savings account that they expect will earn interest of about 4.8% a year, compounded monthly, over the next 13 years.   a) How much will they have saved at the end of 13 years?  I am not sure what the exact formula is to answer this question. Could someone help me with the formula?


Are there any free software packages like Photoshop that can be used to edit and add effects to photos? I want to create a professional look to my photos.

I'm looking to find a free program that allows me to edit my images.  The ones I have used so far are very limited, so if you have any ideas please let me know.


I am going to Find Finitely generated module with a submodule that's not finitely generated.please help me!

I'm looking for an example of a finitely generated module with submodules that are not finitely generated.  I've found  dealing with group (i.e. an example of a finitely generated group with subgroups that are not finitely generated). But I can't figure out whether that question do help to this one.  And I actually want to find a more "module-like" example rather than an example derived from a 'strange' group.  Can you please help? Thank you!


The brown button on the top says I have 4 total posts awaiting review, yet when I click on it, I get the screen above, showing I have 0 tasks to review.  I don't get what that number is supposed to represent.   This has happened before, where it would show up as 10, yet only 2 questions would show up under Close Votes.

Since a , I see more than I should:    I see no reason to see 134 posts are awaiting review, when there is literally nothing I can do about them. I think it is a bug, because notification is meant as something that will make me act. When I know I usually can't, obviously I will start to ignore it.  If it's not a bug, please remove bug tag and explain how it is supposed to be useful, or how can I switch to only seeing notifications about things I can act on.  Note that apaprently there are no flags for me, neither. I see only stats, migrated, close, delete, there, as if there was no flags waiting:    If you expect us to click on it every few minutes  just to see personalized numbers next to queues, why don't you simply query for personalized numbers every few minutes and cache them for us? It should cost you similar, in database usage, and will save us a lot of clicking and frustration.  If all this number means is "there might be reviews, or not" or "for sure there are none"  it would be simpler just to hide "review" link in the second case. We don't need two links with the same function next to each other, thank you, one is enough, and meaningless numbers are only irritating.


I have a macro where I'm not sure when I will need to use it.    I need them built into Excel to be able use them at every start of the program – like you would install some add-on (e.g. Kutools).  How can I do it?

I want all of the macros that I've written to always be available when I'm using Microsoft Excel 2010. How can I do this?


When I'm in the full site and attempt to leave a comment containing fewer than N characters, I get an "N to go..." message.  On mobile web, the comment only fails to submit. No errors or any hints. I propose that the user be somehow alerted on mobile web when a comment is too short.

I know that comments have to be at least 15 chars for the system to post it. I noticed that on the mobile site, there is no "x chars to go..." warning.  If I try to post a comment that is too short, it silently fails and still no mention of minimum length at all.  Can the length counter that is present in the full site theme be added to the mobile theme please?


I have the RT3290 Ralink wireless card run using the original RT2800 driver that came with the 13.04 system, on an ASUS F75V laptop. Every time I reboot, Rf-kill shows the wireless as hard-blocked. It cannot be unblocked using neither Rf-kill nor the supposed Fn+f2 key combination, as various other posts suggest. After boot, in network manager, both the wifi and the airplane mode show up as "off". I dug up a workaround on some obscure forum thread which I unfortunately was unable to dig up again (this was awhile back):   Turn airplane mode on (it stays on). Hit the "on" button for the wireless (it will go back to off very quickly). Immediately send the computer into sleep mode.  Wake the machine up. Wireless is working (it's a miracle!).   Unfortunately, the effects don't last past the next system boot. I am tired and annoyed by having to redo this "trick" over and over again...  So, I tried the official RT3290 driver (Following this post: ).  After reboot, the wireless was supposedly on (not blocked as usual). However, no wireless networks were discovered (and this is at the same location where the RT2800 driver worked previously without fail after the "trick").  I removed the RT2800 driver from the blacklist, and now I'm back to the airplane-sleep trick workaround.  Any suggestions on how to fix it once and for all?  Thanks!  UPDATE: I upgraded to kernel 3.11.5 and tried the rt3290sta driver again. Unfortunately, same result... Wireless is on and unblocked, no networks visible. Just to confirm that I have RT3290,  lspci -nnk | grep RT   yields      03:00.0 Network controller [0280]: Ralink corp. RT3290 Wireless 802.11n 1T/1R PCIe [1814:3290]     03:00.1 Bluetooth [0d11]: Ralink corp. RT3290 Bluetooth [1814:3298]  Out of curiosity, I tried the ole' airplane-mode trick. After emerging from suspend, the wireless worked! What this shows is that either rt3290sta and rt2800pci suffer from the same problem, or, more likely, that the problem is not in the driver itself but elsewhere.

I'm using Ubuntu 13.04 and I have ASUS X550V laptop. This is my rfkill list:  0: asus-wlan: Wireless LAN     Soft blocked: no     Hard blocked: no 1: asus-bluetooth: Bluetooth     Soft blocked: no     Hard blocked: no 2: phy0: Wireless LAN     Soft blocked: no     Hard blocked: yes 3: hci0: Bluetooth     Soft blocked: no     Hard blocked: no   Before you start going: Hey, just turn on your hardware switch, dummy... my hardware switch is Fn + F2 and it works perfectly fine on my Windows boot. But, on my Ubuntu boot it does nothing... All the other Fn + F_ combos work (turn off the touchpad, screen turn off, screen brightness, sound) and they give some kind of visual indicator when I press it.  My lshw log:  *-network DISABLED                 description: Wireless interface                 product: AR9485 Wireless Network Adapter                 vendor: Atheros Communications Inc.                 physical id: 0                 bus info: pci@0000:03:00.0                 logical name: wlan0                 version: 01                 serial: 24:0a:64:28:b4:25                 width: 64 bits                 clock: 33MHz                 capabilities: pm msi pciexpress bus_master cap_list rom ethernet physical wireless                 configuration: broadcast=yes driver=ath9k driverversion=3.8.0-19-generic firmware=N/A latency=0 link=no multicast=yes wireless=IEEE 802.11bgn                 resources: irq:17 memory:f7900000-f797ffff memory:f7980000-f798ffff


One thing to take note is that I am not looking for an example of one case, I am trying to show this in a general form. I understand that this is going to have to involve conditional convergence and proving that series a and b are conditionally convergent, but I don't know where to begin.

If $\sum_j^\infty a_j$ and $\sum_j^\infty b_j$ are convergent, show that  $\sum_j^\infty a_j \cdot b_j$ is convergent or provide a counter example where it is not convergent.  If it can be assumed that one of the given series is absolutely convergent, then I can see a proof that the resulting series is convergent. But I don't see a proof or a counter example when both given series are conditionally convergent.


I have a data set for which I would like to calculate the inter-rater reliability. However, this data set does not seem to fit the typical models that conventional algorithms allow for.  My data set has $r$ raters, $n$ subjects, and $q$ categories. Raters can give each subject anywhere from $0$ to $q$ of the categories.  My understanding is that this means that Fleiss' kappa and Krippendorff's alpha cannot be applied here because they assume that raters give each subject just 1 category. Does anyone have a suggestion for an algorithm that I can use for this data?

I have over 400 open-ended responses. The total has been coded by one rater, and a 10% identical sample of the total has been coded by 2 raters. There is a choice of 14 nominal codes, of which the rater can use any number per case, though most cases have between 1-4 codes. Which statistical test is the most appropriate to determine if I have inter-rater agreement on the 10% sample?   Also am I right in assuming that I will need to treat each code as a variable and look for the level of agreement for each variable?   I'm using SPSS 21.  Much thanks, Kellie


Following are two statements from Enderton's book on set theory, I fail to understand that if empty set is a subset of every set then why can't it be a subset of $\{ \{ \emptyset \} \} $  (1) $\emptyset \subseteq A $, ($\emptyset$  is a subset of every set)  (2) $\{ \emptyset \} \nsubseteq \{ \{ \emptyset \} \} $·  $\{ \emptyset \} $ is not a subset of $\{ \{ \emptyset \} \} $ because there is a member of $\{ \emptyset \} $, namely $\emptyset$, that is not a member of $\{ \{ \emptyset \} \}  .$

$\{\emptyset\}$ is a set containing the empty set. Is $\{\emptyset\}$ a subset of $\{\{\emptyset\}\}$?  My hypothesis is yes by looking at the form of "the superset $\{\{\emptyset\}\}$" which contains "the subset $\{\emptyset\}$".


I'm using Ubuntu 11.10.  The python 2.7.2 provided has a bug that has been corrected in the latest 2.7.2 sources from the python repository.  What is the recommended way to replace the ubuntu provided python with the python from source? Or put another way, how do I "update" the ubuntu-provided one?  Ideally, I would just be able to create new .deb(s) that "update" the python2.7/python2.7-dev provided by Ubuntu.

I want to install the latest Python tarball on Ubuntu, downloaded from .  Is this is a correct way to install?  ./configure make make install   If not, how do I do that?


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

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


(Python 3.5) I have this string: 2021-05-05T13:13:56+00:00  I want to transform it to date object to perform latter actions on it. I've tried the following: d= "2021-05-05T13:13:56+00:00" dt = datetime.strptime(d, '%Y-%m-%dT%H:%M:%S')  Which trows, as expected:  ValueError: unconverted data remains: +00:00  I do not know what are exactly these elements and, refering to , I do not find what it could refer to. How to convert this string as a date object ?

I need to parse  strings like "2008-09-03T20:56:35.450686Z" into Python's datetime type.  I have found  in the Python standard library, but it is not very convenient.  What is the best way to do this?


I'm trying to install VM Player on Ubuntu 14.04.1 LTS.  I've seen threads for earlier versions of Ubuntu that say to install build-essential and linux headers first.  It appears that linux headers is already the newest version.  However build-essential will not install for me.  sudo apt-get install build-essential  Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package build-essential   Is there something I am missing here?  Thank you in advance for your help.

When I try to install any package through the command line, I get an error.   $ sudo apt-get install <package> Reading package lists... Done Building dependency tree        Reading state information... Done E: Unable to locate package <package>   Can anyone help me on this?


What is the name of movie where they spray some kind of chemical into the atmosphere to cool down the Earth but then they end up using way too much and the Earth goes into another ice age.

I read it in Czech translation in the 90s. It was a series of books in a postapocalyptic frozen world with train traffic only - with different class (color ranking) and some kind of new human life form, which is better adapted to cold environment.


I went through this question posted previously here:   I am collaborator for  repository. Will there be an option to make the repositories I contributed as public? I did this for organizations but couldn't do it for repositories I contributed to (these are not categorized in to an organization). So I cannot see the repositories I contributed.

On Careers, when you try to add open source GitHub entries, it shows you repos which you own or are owned by an organization which you collaborate on.    This would be fine with me; that just means that there isn't any fancy fetching of the project details via the API.  However, it isn't possible to add any GitHub projects via the "other" button; it throws the error "Please use our GitHub page (/import/github/88888) to add Github projects.".  Which means that I can only link to a small subset of the projects available on GitHub, even though I can link to almost anything else on the Internet via the other option.  Could the restriction on GitHub links in the "other" form be removed? It could instead be replaced with a non-blocking "warning" sort of thing.  Alternatively, keep a textbox at the bottom of the GitHub repo list where I can enter my own repo.


In synchrotrons electrons lose energy while emitting light so accelerating fields are used to boost up their speed back to >99% of light speed.  Why RF (time varying) fields are used for accelerating electrons? Why not constant field?  In  it is said that the energy gain from a varying field is: $$\Delta W = q V_0 T \cos\phi = \Delta W_{\text{DC}} T \cos\phi$$  where $\Delta W_{\text{DC}}$ is the the energy gain from a static DC field and $T$ is the transit time factor, $T = \frac{\beta\lambda}{\pi L} \sin\frac{\pi L}{\beta\lambda}$.  But isn't $T\cos\phi$ always smaller than 1?

In Synchrotrons I think they use microwaves to accelerate the electrons bundles that fly through-how does putting a microwave through a cavity accelerate an electron? I know that the Electric and Magnetic fields could and do have an effect on the electron, but if the radiation is moving parallel to the electron, wouldn't the force be perpendicular? Also, how exactly does the microwave radiation look in the vacuum chamber? Are the two ends constant nodes?


I have tried using both \n and \r\n however, the exported file does not contain the line break. Any idea what I am missing? I would like the text to return as: indexname_text indextype_text  Below is my code <!-- Button to download --> <button type="button" class="button" id="dwn-btn" style="vertical-align:middle">Download as .bat file</button>  document.getElementById("dwn-btn").addEventListener("click", function () { var copyIndexNameField = document.getElementById("indexName"); var copyIndexName = document.getElementById("indexName"); var copyIndexTypeField = document.getElementById("IndexTypeCheckBox"); var copyIndexType = document.getElementById("IndexTypeTextBox"); var output = document.getElementById("output"); if (copyIndexNameField.value) {     indexname_text += "--index-name " + copyIndexName.value + " "; } if (copyIndexTypeField.checked) {     indextype_text += "--index-type " + copyIndexType.value; } output.value =      + indexname_text     + "\n"     + indextype_text; var text = document.getElementById("output").value; var filename = "export.bat"; download(filename, text);  function download(filename, text) { var element = document.createElement('a'); element.setAttribute('href', 'data:text/plain;charset=utf-8,' + encodeURIComponent(text)); element.setAttribute('download', filename); element.style.display = 'none'; document.body.appendChild(element); element.click(); document.body.removeChild(element);

How can I split long commands over multiple lines in a batch file?


Sentence: "Two weeks seems to be the virus's maximum incubation period."  What is the subject of the sentence? I can't figure out if it's the virus or the incubation period. Also, generally, when you have a plural noun, you're supposed to use "seem" (eg. Those cats seem upset) as opposed to "seems" when you have a singular noun (eg. That cat seems upset), but here, "seems" works alongside "two weeks". Why?  Thank you.

When writing about specific quantities, should the verb reflect a singular or a plural value?  Do abbreviations vs. spelled-out words make any difference?  I took 2 ml of water, which was/were then added... Six microliters of protein solution was/were placed in a centrifuge...


How much minced garlic is equal to 3 medium garlic cloves?

I have a recipe that calls for 2 cloves of garlic, but all I have is minced garlic. How much minced garlic do I use per clove?


I'm using overleaf to write my mnras report and I get this error when I am writing a caption for a figure.  ./main.bbl:1: pdfTeX error (ext4): \pdfendlink ended up in different nesting le vel than \pdfstartlink. \AtBegShi@Output ...ipout \box \AtBeginShipoutBox                                                \fi \fi  l.1 \begin{thebibliography}{1}   My caption is this:  \begin{figure} \includegraphics[width=0.5\textwidth]{SED} \caption{Graph of relative flux against observed wavelength for a  redshift 7 galaxy depicting the 4 wavelength breaks discussed in section  1.3. The blue and green shaded areas at the bottom are bands used in the Hubble Space Telescope, and the red areas are} \end{figure}   but as soon as I add the next word in the caption, I get the above error. Can anyone help me please!

I started using showkeys in one of my documents and see this error  \pdfendlink ended up in different nesting level than \pdfstartlink   A bit of google suggests that this "happens when hyperref is used under pdftex and a citation splits across a page boundary". (See: ).  But this package is only useful at drafting stage where the text is changing frequently i.e. the chance of the error is high. Is there a general way to smoothly use showkeys with hyperref? Thanks.


I have a Samsung SSD 850 EVO installed in February I believe. No problems thus far.   Recently (I'd' say past few days) I noticed my free space going down more than expected. I was at 293 GB free (out of 500 GB total) a few weeks back. Somehow yesterday I was in the mid 100s (around 150, say) remaining. Several hours ago I was at 95.63 GB remaining. Right now, I am at 65.93 GB remaining! Worried I would be able to operate soon.   Does anyone know anything about why or how this is happening and/or how I can stop and subsequently reverse the trend?

Every few days I get notices on my MacBook that it's running or run out of hard drive space. Curiously, restarting the computer will enable me to recover gigabytes of space (this past time, it was able to recover about 2.2GB). However, I can't identify anything in my personal activity that consumed that space.  It's possible that it's a rogue iTunes podcast or a huge software update that my Mac is automatically downloading - would either of these reclaim the space upon a restart?  One possibility that I can think of is that FileVault has some sort of disk leak, allocating but not freeing files. Does this make sense? Is there a tool that I can run to determine where this space is going? Assuming it is FileVault, should I try to disable it? What's the best way to turn of FileVault on a nearly full computer?


I'm creating a simple music player but it keeps getting an error java.lang.NoClassDefFoundError I'm using jacomp3player library  Errors can be found at line:  at app.MainActivity.mp3Player(MainActivity.java:185)     at app.MainActivity.initialize(MainActivity.java:83)     at app.MainActivity.<init>(MainActivity.java:65)     at app.MainActivity$1.run(MainActivity.java:52)   line 185:   private MP3Player mp3Player(){        185 ->     MP3Player mp3Player = new MP3Player();             return mp3Player;         }   line 83:  player = mp3Player();   line 65:  public MainActivity() {     65 ->   initialize();     }   line 52:  52-> MainActivity window = new MainActivity();   Here's my full code:   I think I'm having trouble with the code hierarchy but I can't figure it out thanks for the help!

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


I connected my PS4 controller to my PC and I tried going back on to my console but when I press the button, the sensor light keeps flashing. I pressed reset and also pressed the PS button and share button together but I get nothing.

I was playing my PS4 two days ago and then packed it up with two controllers that were both connected to this PS4.   I got to where I was going, set everything up and now the controllers won't connect. They show pulsing orange when they plug in, but when I hit the PS Button to connect, it blinks white 1-2 times and goes back to orange.   I have tried resetting them both.  Can anyone help?


Could you tell me which is correct to say,  "Today is one of my friends' birthday." or "Today is my friend's birthday."  Thank you for your advice!

When we refer to a house that belongs to a family, we say "family's house". Pluralizing family gives us "families". Referring to the houses of several families, we say "families' houses". Forming the plural possessive in such a case is rather simple.  I encountered a more complex use of this recently - referring to a single house owned by a single family in a set of houses owned by a set of families.  We can say "the families' houses" to refer to all of the houses owned by all of the families.  We can say "one of the families' houses" to refer to one of the houses owned by one or more of the families. In this context, "one of" applies to "the families' houses".  If we were instead to apply "one of" to "the families", and want to refer to the one house owned by "one of the families", how would this be written?  My first though was "one of the families's house", taking "one of the families" as a single noun and appending 's to it. This looks (and sounds) a bit strange, though. "One of the families' house" and "one of the family's house"/"one of the family's houses" seem wrong to me, and I can't really determine the correct way to say/write this.  Is there a definitively correct way that this should be written?  EDIT: To clarify, although I think I made it clear, in this context, there are several families, and each owns one house. The goal of the sentence is to refer to one of those houses without stating which specific house. Example: "The players and their families want to celebrate their team's victory; this will likely entail a party at one of the families's house".


Can moderators review unlimited posts in a single review queue within a day? I saw one moderator review more than 400 yesterday in Stack Overflow first posts review queue. Today also he's reviewed more than 100 since start. . (Normal daily limit is 40 for Stack Overflow) Is this available only for moderators or what is the logic behind this?

W.K.T, any user(with more than 2k rep) can review 20 suggested edits per day.  Today I saw the newly appointed moderator  reviewed more than 20.    Is it possible for moderators to review more than the daily limited count?  If yes, can any moderators can do it at any time?  I didn't see this before.


Why were Fock Space and Hilbert Space used in quantum field theory? What was the motivation for choosing them over other mathematical techniques?

I am reading Why we do quantum mechanics on Hilbert spaces by Armin Scrinzi. He says on page 13:      What is new in quantum mechanics is non-commutativity. For handling this, the Hilbert space representation turned out to be a convenient — by many considered the best — mathmatical environment. For classical mechanics, working in the Hilbert space would be an overkill: we just need functions on the phase space.   I understand the definition of a Hilbert space, but I do not understand why non-commutativity compels us to use Hilbert spaces.  Can someone explain?


I'm trying to locate a story I read sometime in the seventies in an anthology so it may have been written earlier. A plague/alien parasite has infected earth wreaking havoc. It's communicated by touch (and those infected develop a compulsion to touch other people). Those people infect have grey skin caused by, it turns out, massive nerve growth.   The protagonist might have been a priest ministering to the "sick". And in the advanced stage the infected might have grown a third eye. It's also possible the infected were called "feelies" (but using this to search only turns up stories where feelies are a future version of tactile TV).  Any help appreciated. Thanks.

I'm looking for the title of sci-fi novelette about where a symbiote has infected a lot of people on the planet, and the infected are persecuted. It turns out that the symbiote is beneficial.  The story's main character is initially against those with a symbiote, but he willingly takes it on at the end after a romance with an infected person.


I need to proof the following statement:  Let $a, b, n \in \Bbb{Z}$  with $ n≥ 2, gcd(a,n)=1$. Proof that if $s_{1},s_{2}$ are solutions to $ax\equiv b \pmod{n}$, then $s_{1}\equiv s_{2} \pmod{n}$.  I don't know where to start my proof. I do know that if you get any solution, then by adding the modulo you get equivalent solutions. Then, there are n possible solutions. But I don't think my argument is correct.

How can I prove that $\,ax\equiv b\pmod{\! n}\,$ has a unique solution if $\,\gcd(a,n) = 1$?  I suspect that the Bezout identity for $\,\gcd(a,b) = 1$ is the key but I don't see how to proceed.


I have an image (image.pdf, ). This is how the image looks like:  And this small TeX code:  \documentclass{standalone} \usepackage{graphics} \begin{document} \includegraphics{image.pdf} \end{document}   This returns the following output:  Obviously, there are a few things missing, e.g. b/a and z. Why?  Can anyone reproduce this? I am using TeXShop (Typeset, LaTeX) on a MacBook Pro.

In the following example, the 'ff' ligature in the figure labels (in 'differential') disappears when pdflatex is used, but the fault does not occur if latex-dvips-ps2pdf is used instead. Both lualatex and xelatex produce the correct results, using the pdf version of the figure. Is there a problem with the figure, or is this a bug in pdftex?  \documentclass{article} \usepackage{graphicx} \begin{document} \includegraphics[width=0.9\textwidth]{Cluster2} \end{document}


I'm trying to vertical align all the contents inside a div, here it's the html:

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       <Button text="No Acepto" bgColor="#DEDEDE" textColor="#404040" onClick={Hola}></Button>              <Button text="Estoy de Acuerdo" bgColor="#57DE7F" textColor="#F6F6F6" onClick={Hola}></Button>

   Here's the css (React Styles):  this.CookieBarStyle = {   backgroundColor: '#F6F6F6',   color: '#404040',   padding: '8px 15px',   boxSizing: 'content-box' } this.CookieBarTextStyle = {   display: 'inline-block',   width: '65%',   paddingLeft: '35px' } this.CookieBarButtonsStyle = {   display: 'inline-block',   width: '30%',   textAlign: 'right' } this.CookieBarLinkStyle = {   color: '#525AB5' }   Here's a screenshot of how it is looking atm:     Basically everything should be vertically centered, the cookies, the text and the buttons

I have a div with two images and an h1. All of them need to be vertically aligned within the div, next to each other. One of the images needs to be absolute positioned within the div. What is the CSS needed for this to work on all common browsers?

testing...


I am using tinymce editor for writing the text into the database using php. Whenever I am writing anything into the editor using keyboard then the code works absolutely fine. But whenever I copy and paste lorem ipsum text into the tinymce editor then I am getting a syntax error and the database is not getting updated.  following shows the syntax error which of course in not going to be helpful. But still for completing the post I am showing the syntax error related to mysql that I am getting while adding something to the database using tinymce.  You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'Open Sans', Arial, sans-serif; text-align: justify;">It is a long established fa' at line 1

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


Problem: Let $R$ be an integral domain with fraction field $K$. Assume that $x \in R$ or $x^{-1} \in R$ for all $x \in K^{\times}$. Prove that $R$ is a local ring (the ring $R$ is said to be a valuation ring of $K$).  Attempt: I don't really know how to begin. There a different possibilities to show that $R$ is a local ring. Either showing it has a unique maximal ideal, or showing that $R \setminus R^{\times}$ is an ideal, or that the sum of two non-units is a non-unit.  I take $r \in R$ and $x \in R \setminus R^{\times}$. I want to show that $rx \in R \setminus R^{\times}$. I can consider $rx$ as an element in the fraction field $K$. Then either $(rx)^{-1} \in R$ or $rx \in R$. But the second is trivial. So I'm not really sure how to use my assumption.   Any help is appreciated.

A subring $R$ of a field $K$ is said to be a valuation ring of $K$ if for each $x$ $\in$ $K^{*}$ we have either $x$ $\in$ R or $x^{-1}$ $\in$ $R$. How can I show that the valuation ring has a unique maximal ideal?


The following question solves the existence of such a partition: . However, I'm trying to count how many such 2-partitions exist. Specifically,  Let $X = \{1, \cdots, 2n\}$. How many unique $S \subset X$ has cardinality $n$ and $\sum S = 2n^2+n$?  I'm trying to count the number of exact sequences on finite dimensional vector spaces $\mathbb R^1, \cdots, \mathbb R^{2n}$.

For any positive integer $n$ (using integer division only), let $P(n)$ denote the number of ways in which the integer $(n^2+n)/4$ can be expressed as a sum of exactly $n /2$ distinct elements of the set $\{1,2,3,\dots, n\}$.    What is $P(n)$ in terms of n?  Specifically, how exponential is it? Is this less than $2^{n/2}$?


From what I understand about Hawking radiation, a virtual particle comes into existence very near the event horizon of a black hole. This causes one part of the particle to fall into the black hole, and the other can radiate outwards. When the anti-particle falls in, it will collide with a particle and annihilate, making the black hole lose mass.  Does that mean that it's only anti-particles that are being captured by the black hole? Wouldn't we expect the non-anti-particle to fall in just as often, which would make the black hole stay about the same mass? Is there any reason that an anti-particle from a pair of virtual particles would be more likely to descend into the black hole?

I was reading Brian Greene's "Hidden Reality" and came to the part about Hawking Radiation. Quantum jitters that occur near the event horizon of a black hole, which create both positive-energy particles and negative-energy particles, produce the so-called Hawking radiation. However, I do not understand why only the negative-energy particles are being absorbed into the black hole, while the positive-energy particles shoot outward. Shouldn't there be 50/50 chance that each type of particle is being absorbed by the black hole? Also, the book mentions that a negative-energy particle would appear to an observer inside the black hole as positive. Why?


$$\sum_{i=1}^k i\cdot2^i$$  I'm working on a recurrence relation question and now I'm stuck at this point. I have no idea how to simplify this down to something I can work with.  Can I seperate the terms into $$\sum_{i=1}^k i \cdot \sum_{i=1}^k 2^i$$ and then just use the geometric series?

How can I evaluate $$\sum_{n=1}^\infty\frac{2n}{3^{n+1}}$$? I know the answer thanks to , but I'm more concerned with how I can derive that answer. It cites tests to prove that it is convergent, but my class has never learned these before. So I feel that there must be a simpler method.  In general, how can I evaluate $$\sum_{n=0}^\infty (n+1)x^n?$$


I am traveling and using a 3G mobile internet provider, it has limit of 3GB download every 7 days. So I was wondering what tweaks can I apply in Ubuntu 12.04.3 to minimize internet usage. I already disabled flash and images on my browser, but what else could I do. Are there some programs that use bandwidth on the background I can disable or any other tips?

I am getting complaints that I consume lots of internet bandwidth.  Is there any software that can limit internet bandwidth on my computer from my own computer? I use Firefox as browser and use bittorrent and download software from software center.  (Is there also a way to monitor it?)


I have currently Android 6.0 Device but app which I am trying to install only supports Android 7.0+. I am thinking of installing lineage OS. Is there Lineage OS 7.0 etc. equivalent of Android 7.0, so that app can be installed or I need to stay with android.

There are several reasons to be looking for a ROM:   Upgrading or downgrading your stock ROM Looking for firmware from a different region/language Flashing a custom ROM for different features, removing bloat, etc.   But where can one find ROMs in the first place?  What sites are likely to have the ROM I need?  ; please add to the wiki answer instead of posting separate answers.  See also:


I've anonymized the affected user profile, but came across this after seeing a comment on another meta question saying that the reason was visible on the profile; but initially not being able to find it because i was looking at the suspended users meta profile.

I recently discovered that there was a high-rep user suspended on Arqade, so that they could calm down a bit. When I was looking at their profile, I noticed that the suspension reason was shown on their main profile, but not on their meta profile.  Main:   Meta:


I have a bike with a 7 speed cassette. My question is can I swap it to a cassette with more speeds (like 10). I will change the derailleur to a compatible one.

My Bridgestone MB-5 currently has a 7-speed rear wheel. I'd like to convert it to a 10-speed. Is this possible? Is it practical?


I have the below query :  select databasename  from somedb.dbo.bigtable l where databasename ='someval' and source  <>'kt' and not exists(select 1 from dbo.smalltable c where c.source=l.source)   The above query completes in three seconds.  If the above query returns any value, we want the stored procedure to EXIT,so I rewrote it like below:  If Exists( select databasename  from somedb.dbo.bigtable l where databasename ='someval' and source  <>'kt' and not exists(select 1 from dbo.smalltable c where c.source=l.source) ) Begin Raiserror('Source missing',16,1) Return End   However this is taking 10 minutes.  I can rewrite the above query like below, which also completes in less than 3 seconds:    select databasename  from somedb.dbo.bigtable l where databasename ='someval' and source  <>'kt' and not exists(select 1 from dbo.smalltable c where c.source=l.source if @@rowcount >0 Begin Raiserror('Source missing',16,1) Return End   The issue with above rewrite is that the above query is part of bigger stored procedure and it returns multiple result sets. In C#,we iterate through each result set and do some processing.  The above returns an empty result set, so if I go with this approach, I have to change my C# and do deployment again.  So my question is,     why does using just IF EXISTS changes the plan to take so much time?   Below are the details which may help you and let me know if you need any details:   Create table and statistics script to get same plan as mine   Slow Execution plan Fast Execution plan         Note: Both queries are the same (using parameters), the only difference is EXISTS (I might have made some mistakes while anonymizing though).  The table creation scripts are below:    -- small table stats   -- big table stats

When I run the following code it takes 22.5 minutes and does 106million reads. However, if I run just the inner select statement by itself it only takes 15 seconds and does 264k reads. As a side note, the select query returns no records.  Any idea why the IF EXISTS would make it run so much longer and do so many more reads? I also changed the select statement to do SELECT TOP 1 [dlc].[id] and I killed it after 2 minutes.   As a temporary fix I have changed it to do a count( * ) and assign that value to a variable @cnt. Then it does an IF 0 <> @cnt statement. But I thought EXISTS would be better, because if there were records returned in the select statement it would stop performing the scan/seeks once it found at least one record, whereas the count(*) will complete the full query. What am I missing?  IF EXISTS    (SELECT [dlc].[ID]    FROM TableDLC [dlc]    JOIN TableD [d]    ON [d].[ID] = [dlc].[ID]    JOIN TableC [c]    ON [c].[ID] = [d].[ID2]    WHERE [c].[Name] <> [dlc].[Name]) BEGIN    <do something> END


I need some help getting into my dad's admin account on my laptop.  I need to know the password because my dad forgot it.  I need to be able to do this without Command Prompt, because my dad blocked it.  Any methods that don't require admin permisson would be helpful.  Thanks :)

I don't want to reset the password nor delete it. I need to know the password. What can be done? Specific software for that? Easier way of getting the password from inside a non-admin account through Windows itself or reboot is needed? Thanks  EDIT: Also, where are the password files stored? If I get in the system files with another bootable OS, I can read those and get the pwd from it.   EDIT: I don't want to reinstall Windows, I want the password.


Question : Six bells commence tooling together and toll at intervals 2,4,6,8,10,12 minutes.In 30 hours,how many times do they toll together? I found the LCM of 2,4,6,8,10,12 minutes in order to find the minimum minutes after they will tool together. LCM (2,4,6,8,10,12)=120 It means they will toll together after 2 hours that is 120 mins.So in in 30 hours they should too together 15 times( 30/2). But the answer provided in the textbook is 16 times.Can you please explain how they got 16?

There are 20 poles with a constant distance between each pole. A car takes 22 seconds to reach the 12th pole starting from the first pole, with a constant speed between each pole. how many seconds will it take to reach the last pole?   Is the answer 36 seconds?   since $\frac{22} {12}  = 1.83 $  $1.83 \times 20 = 36.67 $


I have a one way ticket from BKK-TXL with stopover in CGN. I would rather get off in CGN and start my land travel in Cologne going to Amsterdam and other parts of Europe, instead of landing in Berlin. So I would like to miss my CGN-TXL leg on purpose. Is this okay?  Addendum: I will have no check-in baggage and do not have  a return flight. The CGN-TXL is my last leg. Looking at the answers below, seems it is okay for me to purposefully miss the CGN-TXL leg. So thank you everyone.

Assume I have a flight ticket from A->B->C and at A I checked in luggage all the way to C. However after the first flight I don't board the second flight but decide to remain in B.  As I understand procedures my luggage will need to be unloaded again from the plane in B when they notice I did not board the flight.    How and when can I retrieve my luggage at B? (Or if not, what is the fate of my luggage?) Is there any way I can advise airport/airline staff in B to not load my luggage in the first place? (I understand that asking to do so when checking in in A would be declined / met with a fare recalculation)   This question is different from  in that I am looking for a general answer, whereas in that case B happened to be the port of entry to the US where you have to collect your luggage in any case. Also it is different from   in that I do want to check in  luggage from A to B. Finally I am also aware that possible further legs of my trip would be cancelled.  is asking essentially the same but was marked duplicate to the above two questions that do not answer my question.


If you have a manual encryption system where the keying is done by extracting a key from a book, a major weakness is that an adversary can search trough all existing books to find a perfect Match and thus the key. But isn't that very theoretical since not all books can be accessed by every one on the internet?   What can be done to strenghten such a book derived key?

I've seen ciphers (usually in spy drama shows) that involve taking a book and writing down an index to individual characters. Essentially it's a keyed substitution cipher, where the key is the name and exact edition number of the book.  Example:  Imagine a book that has 500 pages, with approximately 60 lines per page and 80 characters per line. We might write 238:4:64 to specify that we're on the 238th page, 4th line, 64th character. A five character message might be encrypted into 114:25:22 374:41:46 182:17:62 63:53:8 50:8:18.  Without knowing what the book is, I would imagine this is provably secure as long as the person encrypting never re-used an index. Am I correct in this assumption?    For fun, you could try this out:  12:9:3 183:15:7 238:14:11 310:9:38 194:11:17 7:1:1  I'm using a page:line:character format, ignoring titles, spaces and punctuation. The book is Charles Darwin's , 6th edition.  N.B: I'm not trying to get you to crack this, just adding it because it nicely demonstrates the way this works :)


I have java web-app project, which is compiled and working. It consists of .class files, which I can't edit. Is there any tool with which I can uncompile whole project and keep it's structure? I know there are tools like JAD, which uncompile only single files

What program can I use to decompile a class file? Will I actually get Java code, or is it just JVM assembly code?  On Java performance questions on this site I often see responses from people who have "decompiled" the Java class file to see how the compiler optimizes certain things.


Out of simple curiosity, do DSLR cameras produce an inverted image on the sensor, with the image being flipped by software?  I've dabbled with astronomy prior to my current interest in photography and own a 3 inch refracting telescope. Here the object lens produces an inverted image. An extras lens could be introduced to provide an upright image but this would reduce the amount of light that could be captured. I use a Panasonic Lumix GX80/GX85, but would assume all digital cameras would operate in a similar fashion?

I have a really nasty looking piece of dust on my 550D's sensor, situated in the top right-hand corner of each image I take with anything higher than f/11. I am going to get a decent sensor cleaning kit, but I'd like to know which corner of the sensor should I focus on to get rid of this annoying particle?  In other words, does a lens flip the incoming light from left to right and turn it upside down? I think that's correct, so that means the answer in this diagram will be A, correct?    And before anyone asks - yes, I will clean the entire sensor while I'm in there, but this will help me focus on this particular (pun intended) problem. Thanks in advance!


March 12th 2020, US banned immigration from people who has been in the Schengen area for the past 14 days. Does this ban also apply for someone arriving from the Schengen area to Puerto Rico?

This community wiki explains the current restrictions by the United States of America on the entry of individuals who may pose a risk of transmission of the SARS-Cov2, the virus which causes the Covid-19 disease.


Bran told Theon he'd be going then warged into a few crows. What did he accomplish as the crow?  It didn't look like he posed any  threat to the Night's King. And if it was reconnaissance he didn't debrief with anyone about what he saw.  What was the strategy there?

I still don't understand what exactly he was hoping to accomplish during that scene where      Theon fights to protect him,   because it looked like nothing of any major significance happened besides warging into a flock of ravens for a minute and then tapping back in.


Today I was wondering if I could run a Program I installed on a virtual drive as an administrator?  I installed Cain and Abel on this drive, When I run the program it works fine. But in order for it to actually work, you need to run as admin.  Does anyone know how I can accomplish this?

I just want to know if it's possible to get Cain and abel installed in ubuntu, it would really help my work instead of dual booting back to my windows 7 just to use it. THanks!