I am an absolute beginner with Git and clone. So I cloned a Git repository (see picture). But where is the folder, where can I see the content?

Ok, after seeing , I have decided to skip to the end and go with .  So what I need is a beginner's practical guide to Git.  "Beginner" being defined as someone who knows how to handle their compiler, understands to some level what a  is, and has touched source control without understanding it very well.  "Practical" being defined as this person doesn't want to get into great detail regarding what Git is doing in the background, and doesn't even care (or know) that it's distributed.  Your answers might hint at the possibilities, but try to aim for the beginner that wants to keep a 'main' repository on a 'server' which is backed up and secure, and treat their local repository as merely a 'client' resource.  So:  Installation/Setup    How do you set up Git?  Try to cover Linux, Windows, Mac, think 'client/server' mindset.         Working with the code          How do you handle binary files (visio docs, for instance, or compiler environments)? How do you merge files changed at the "same time"?    Tagging, branching, releases, baselines    How do you pull a particular 'release'?   How do you resolve conflicts and complete the merge? How do you merge parts of one branch into another branch?        Other   Describe and link to a good GUI, IDE plugin, etc. that makes Git a non-command line resource, but please list its limitations as well as its good.    - Cross platform, included with Git  - Cross platform history viewer, included with Git  - Mac OS X  - Mac OS X history viewer  - Cross platform, commercial, beta  - console GUI for Linux  - GUI for Windows, Linux  - package for Windows, includes friendly GUI  Any other common tasks a beginner should know?     How do I work effectively with a subversion repository set as my source control source?   Other Git beginner's references                 Delving into Git     (and )    I will go through the entries from time to time and 'tidy' them up so they have a consistent look/feel and it's easy to scan the list - feel free to follow a simple "header - brief explanation - list of instructions - gotchas and extra info" template.  I'll also link to the entries from the bullet list above so it's easy to find them later.


I'm creating a debian package primary.deb (custom, home-made package for internal use) that depends on secondary.deb (hosted in external PPA). I'd like the users of primary.deb to not explicitly have to add the PPA to their package manager by running a command before installing it. Is there a way to pre-download secondary.deb, include it in primary.deb and have it automatically installed during the installation of primary.deb? There is a  that answers this question with no. However, almost 7 years have passed and I'm wondering if the situation changed.

When creating a .deb package I create a file named control that contains some fields:  Package: my-qt-app-name Version: 0.01 Architecture: all Maintainer: my name <my email address> Installed-Size: 2 Depends: some-package-from-ppa Section: extras Priority: optional Homepage: my homepage Description: some description   some-package-from-ppa is not installed on the computer. It can be installed only adding a PPA, running apt-get update and then apt-get install some-package-from-ppa.  Can a control file from a deb package contain a PPA address and install that package when the deb file is installed?


I have two time series. I want to evaluate if two time series are different enough in one window or space of time. The objective is to trigger an alert when one time series divert significantly from the other. I attach one example where the blue line has a small bump that the red line doesn't. How can I statistically evaluate that this gap is high enough to consider that from 12:00 to 15:00 there has been a deviation?  This may seem as a duplicate for  but I don't want to compare the whole time-series sequence but rather segments or windows of it.

I have two time series, shown in the plot below:    The plot is showing the full detail of both time series, but I can easily reduce it to just the coincident observations if needed.  My question is: What statistical methods can I use to assess the differences between the time series?  I know this is a fairly broad and vague question, but I can't seem to find much introductory material on this anywhere. As I can see it, there are two distinct things to assess:  1. Are the values the same?  2. Are the trends the same?  What sort of statistical tests would you suggest looking at to assess these questions? For question 1 I can obviously assess the means of the different datasets and look for significant differences in distributions, but is there a way of doing this that takes into account the time-series nature of the data?  For question 2 - is there something like the Mann-Kendall tests that looks for the similarity between two trends? I could do the Mann-Kendall test for both datasets and compare, but I don't know if that is a valid way to do things, or whether there is a better way?  I'm doing all of this in R, so if tests you suggest have a R package then please let me know.


Using Mathematical induction prove the above proposition.  Basis step can be verified easily. But how can i show that it is true for $p(n+1)$.

I've done the base step, but how do I prove it is true for $n+1$ without using a fallacy? $$4(n!)>2^{n+2}\quad \text{for } n\geq 4$$ Please help.


I'm working on a document in which I define some numbers. I want to print at the beginning the sum of all these numbers. It's something like the desired result described in this question , but I could not modify that code to obtain what I want.  Here is an example of what I want  \documentclass[leqno]{article} \newcounter{totaldepuntos} \newcommand\puntos[1]{\textbf{(#1Pt)}\addtocounter{totaldepuntos}{#1}} \setcounter{totaldepuntos}{0} \begin{document} \thetotaldepuntos %Must print 10 \begin{enumerate} \item \puntos{2} Blablabla %Creates an item, put the text ´(2Pt)´ and      %sum 2 to the counter totaldepuntos \item \puntos{4} Blobloblo %Creates an item, put the text ´(4Pt)´ and      %sum 4 to the counter totaldepuntos \item \puntos{4} Blublbublu %Creates an item, put the text ´(4Pt)´ and      %sum 4 to the counter totaldepuntos \end{enumerate} \end{document}

At the beginning of my document, I have created a counter using \newcounter. Over the course of the document, this counter is increases using \stepcounter. How can I display the final value of the counter in a place prior to the the final occurrence of \stepcounter, such as at the beginning of the document?


Let $G=\mathbb{Z_{10}}\times \mathbb{Z_{15}}$. Then,    $G$ contains exactly one element of order $2$. $G$ contains exactly $5$ element of order $3$. $G$ contains exactly $24$ element of order $5$. $G$ contains exactly $24$ element of order $10$.   I know how to calculate number of elements when external direct product of groups is given. But in this case I don't know how to proceed. Please give me some hints. Thanks.

$G=Z_{10}\times Z_{15}$ Then $G$ contains exactly    one element of order $2$ five element of order $3$ 24 elements of order $5$ 24 elements of order $10$   what I think is 1 is correct, not able to guess others.


Everyone knows that the snap of Thanos at the end of Avengers: Infinity War ended the lives of half of all organisms in the Universe. But why did their accessories turn to dust along with the owner?  For example:   Metal arm (from Winter Soldier) Vibranium suit (from Black Panther) Eye of Agamotto, Cloak of Levitation (from Dr. Strange) Jetpack (from Falcon) Iron Spider suit (from Spider-Man)   ...and so on.  Was there any reason for the accessories disappearing as well? It would have expected that only the organic parts (the actual body) would disappear.

Bucky (Winter Soldier) has a metal arm (possibly made from vibranium?) but it's an attachment to his body as far as I understand. Why, when Thanos destroys half of the universe at the end of Infinity War, does his metallic arm also disappear with him? Shouldn't it be left behind as his gun did?


When I discover that an answer has been blatantly stolen from another user's answer I never know whether to comment and ask the user to delete the post or whether to flag it for moderator attention.  What is the best course of action?

How should I act if I discover a user plagiarizing fellow users' posts? What if I find someone plagiarizing external resources without attribution?  See also:


Let $p >3 $ be a prime number and $\Bbb F_p$ denote the ﬁnite ﬁeld of order $p$. Prove that the polynomial $X^2 +X +1$ is reducible in $\Bbb F_p[X]$ if and only if $p ≡ 1\pmod 3.$   Attempt: $X^2 +X +1=\dfrac{X^3-1}{X-1}.$ Now if $x^3=1$ for some $x\in \Bbb F_p$;  $x\in \Bbb F_p^*\implies x^{p-1}=1\implies 3\mid p-1\implies p\equiv 1(\mod 3)$.  How to do the converse?

For which prime numbers p does the congruence $x^2 + x + 1 \equiv 0 \pmod{p}$ have solutions?  We've recently learnt about quadratic reciprocity in class, however I am not sure how to tackle this problem. I have tried starting with the $b^2-4ac$ (discriminant) but that hasn't really helped.


Prove that if  postive intetger $n>1$  then between $ n $  and  $n^2$  is at least one prime. I have known this stronger reslut: But my problem is constant math test,so I guess maybe there exist more simple methods? and  I want to have prove $$\pi(n^2)-\pi(n)>1,\forall n>1$$

Consider the following statement:     For any integer $n>1$ there is a prime number strictly between $n$ and $n^2$.   This problem was given as an (extra) qualification problem for certain workshops (which I unfortunately couldn't attend). There was a requirement to not use Bertrand's postulate (with which the problem is nearly trivial), and I was told that there does exist a moderately short proof of this statement not using Bertrand. This is my question:     How can one prove the above statement without Bertrand postulate or any strong theorems?   Although I can only accept one answer, I would love to see any argument you can come up with.  I would also want to exclude arguments using a proof of Bertrand's postulate, unless it can be significantly simplified to prove weaker statement.  Thank you in advance.


I need a 4*4 grid to fill with selected colors. Basically, I am in search of a \newcommand, like this:  \newcommand{\mygrid}{11/blue, 32/brown} %coordinates/color is passed   which will produce the following grid:  .  Similar questions were asked before:        I tried to start from answers from all the questions, but got lost midway. Any help will be appreciated.  EDIT This is the last workable version I was trying (from ):  \documentclass{standalone} \usepackage{tikz} \usetikzlibrary{calc}  \pgfmathdeclarerandomlist{MyRandomColors}{%     {red}%     {red!25}%     {magenta}%     {magenta!25}%     {olive}%     {olive!25}%     {brown}%     {brown!10}%     {violet}%     {violet!25}%     {gray}%     {purple}%     {yellow}%     {orange}%     {orange!25}%     {cyan}%     {green}%     }%  \newcommand*{\GridSize}{4}  \newcommand*{\ColorCells}{%     \foreach \y in {1,...,\GridSize} {         \foreach \x in {1,...,\GridSize} {             \pgfmathrandomitem{\RandomColor}{MyRandomColors}              \node [fill=\RandomColor, fill opacity=0.4, draw=none, thick, minimum size=1cm]                  at (\x-.5,\y-.5)                 {\x\y};         }%     }% }%  %%%%%   %\listfiles \begin{document} \begin{tikzpicture}[scale=1]      \begin{scope}[thick,]         \ColorCells         \draw (0, 0) grid (\GridSize, \GridSize);         \coordinate (input);     \end{scope}   \end{tikzpicture} \end{document}   EDIT 2 Here's another (based on ) [argument 2 supports placing of grids to a preferred location]:  \documentclass{standalone} \usepackage{tikz,amsmath} \usetikzlibrary{positioning,backgrounds,shadings,calc,patterns, decorations.pathreplacing, fit, arrows} \newcommand{\vrect}[3]{  %   \foreach \mark/\colorname [count=\k] in {#3}{ %       \ifnum\mark=34 \def\mycolorname{\colorname}\fi %   }      \foreach \x in {1,...,4}{         \foreach \y in {1,...,4} {             \foreach \px\py in {#2}{             \node[draw=gray, fill=red!30,thick, minimum size=1cm,  anchor=mid,             ] (z#1\x\y\px\py) at ($(\y,-\x)+(\px,\py)$) {#1\x\y\px\py}; %         }     }     } }   \begin{document}     \begin{tikzpicture}[scale=1]     \vrect{0}{6/6}{12/red,11/green}     \end{tikzpicture}  \end{document}

Can you create images like this:    when you have something like  0 = green (#54ff00) 1 = white (#ffffff) 2 = red   (#ff0000) 3 = blue  (#0048ff)  Image (Python list of integers defined above): [[2,0,0,0,0,0,0],  [0,3,0,0,0,0,0],  [0,3,2,1,1,0,0],  [0,3,2,2,2,1,1],  [0,3,2,0,0,1,0],  [0,0,0,0,0,1,0],  [0,0,0,0,0,1,0]]   with TikZ?  How far I got  The following MWE defines all colors, produces a grid of the correct size (though the size is determined by hand):  \documentclass[varwidth=true, border=2pt]{standalone} \usepackage{tikz} \usepackage{xcolor}  \begin{document}     \newcommand\n{7}     \definecolor{green}{HTML}{54FF00}     \definecolor{wite}{HTML}{FFFFFF}     \definecolor{red}{HTML}{FF0000}     \definecolor{blue}{HTML}{0048FF}     \begin{tikzpicture}         \foreach \x in {1,...,\n}{             \foreach \y in {1,...,\n}{                 \begin{scope}[shift={(\x,\y)}]                   \draw [fill=green] (0,0) rectangle (1,1);                 \end{scope}             }         }     \end{tikzpicture} \end{document}   Of course, I could simpy make a lot of adjusted                   \begin{scope}[shift={(\x,\y)}]                   \draw [fill=green] (0,0) rectangle (1,1);                 \end{scope}   but I've wondered if this can (with reasonable effort) be done in TikZ / LaTeX.  My problem is giving TikZ the color array. I don't have any idea how to do this. I only know two types of looks in TikZ:  \foreach \x in {0,1,2,3,4,5}{...} \foreach \number in {1,...,\n}{...}   I have never seen a nested over a 2D-array. All I have seen so far were 1D-Arrays of tuples (with fixed tuple size).


I suggested edits on a few questions/answers and they are now pending. As the Stack Overflow site only allows 5 pending edits, I would like to know if it is possible to cancel any such edits in order to suggest more substantial ones?    In my particular case, I have two pending edits that are code indentation fixes and I would like to cancel them in order to propose other, more judicious, edits.  This would be especially useful as I have pending edits that are two days old.

Edits made by users who do not have edit privileges are placed in a queue until it is peer reviewed.  E.g., I edited someone else's answer. but changed my mind. If I'd edited my own question/answer, there would be a "Rollback" button, but there's no such button in the scenario I'm describing (at least none that I can see).  This is more relevant today because users can only have at most five edits waiting in the queue, and allowing one to cancel an edit would permit them to free up one of their five pending edits for something else.  Is there a way to remove one's edit from the peer review queue?


For my immediate needs, I've already alerted a site moderator via chat. However, I was thinking this is something that should probably be built into the system somehow.  Today, I came across a user whose display name included some offensive language. Their actual activity on the site (questions/comments/etc.) is generally non-objectionable, so I'm looking for a way to flag the actual user profile instead.  It's also occurred to me that the same need could arise if the user's profile has objectionable content in their "About me" or other unrestricted text fields. However, there so far appears to not be any means for someone to flag profile contents.  Is there something I'm missing, or could this be added?

Is there a mechanism by which we can flag user-names as offensive?


Suppose that I have two continuous functions  $$f : \left[ a, b \right] \rightarrow \mathbb{R} \quad \text{and} \quad g : \left[ a, b \right] \rightarrow \mathbb{R}$$  and they have the following property   $$f(x) \times g(x) = 0 \space , \forall x \space \in \left[ a, b \right]$$  Can I say that one of the functions necessarily has to be equal to $0$?    For example, $f(x) = 0 \space , \forall x \space \in \left[ a, b \right]$.  UPDATE: Ok, I can see from the counterexamples that the affirmation is not true, but now I cannot see in which cases it is true. If I let the function $g : \left[ a, b \right] \rightarrow \mathbb{R}$ be any continuous function, then in that case must I have $f(x) = 0$ ?

Can you give me examples of two functions $f$ and $g$ such that both are non-zero continuous function but their product is zero.


Why this work  $("#tag-search").autocomplete({         autoFocus: true,         source: tags,         messages: {             noResult: '',             results: function () {}         },         select: function (e, ui) {             $('.tags').append('' + ui.item.value + '');             ui.item.value = "";             $('.tag-del').click(function () {                 $(this).parent().remove();             });         }     });   and this no?  $("#tag-search").autocomplete({         autoFocus: true,         source: tags,         messages: {             noResult: '',             results: function () {}         },         select: function (e, ui) {             $('.tags').append('' + ui.item.value + '');             ui.item.value = "";         }     });      $('.tag-del').click(function () {         $(this).parent().remove();     });   I have never understood how javascript is compiled and how work functions! Someone can help me? And last thing: is better write javascript in body page or in a external file? If i should write in external file how can send php response to javascript file? Thanks!

I have a bit of code where I am looping through all the select boxes on a page and binding a .hover event to them to do a bit of twiddling with their width on mouse on/off.  This happens on page ready and works just fine.  The problem I have is that any select boxes I add via Ajax or DOM after the initial loop won't have the event bound.  I have found this plugin (), but before I add another 5k to my pages with a plugin, I want to see if anyone knows a way to do this, either with jQuery directly or by another option.


My computer crashed but the HDD is intact. I have been able to browse that hard drive from another Windows computer, except for the Users folder where I get the message:     "You dont currently have permission to access this folder" [continue] [cancel].    Also, I do not get access denied msg.  When I click continue it just hangs.

I bought a new SATA Hard drive and installed a fresh copy of Windows 7 on it. I also installed my old one beside the new SATA HD.  Now I want to access my images / musics and videos but I get this error:      You dont currently have permission to access this folder, click continue to permanently get access to this folder    and when I click continue, I get this new error:      You have been denied permission to access this folder   when I go to the securiy tabs, my username (which is also the administrator on the pc) is not there - My new HDD is called C: and the old one is E: - I tried  and run the CMD - but the CMD directory is:     C:\Windows\System32>   and my drive is E:.


This paperback was probably from ca. 1970. The well-off don't want their apple-cart upset by alien tech. Hero saves "Polly Ling" from an alien monster, which turns out to be her husband- she's an alien.

As title, seeking the title of a story I read in the mid 1970s. I'm fairly sure it was a novella in an anthology.  Plot details I can remember - I think main character's family name was Monk.   His father had apparently been killed when the space station he was aboard crashed on the Moon - it later transpires that the station was deliberately crashed to conceal contact with an alien starship, and his father was still alive. The crew of the starship included various races - one appeared to be a beautiful human woman, while another ( the engineer ) looked like a giant squid.  After the main character's father died of cancer, the engineer also turned out to be a microbiologist and was able to cure the cancer and bring him back to life. Other things include a vehicle which was able to go out-of-phase with normal matter and travel through solid objects like the earth.


I have lost my admin as well as secondary email (use as to retrieval of admin pwd) password. Please suggest steps which really works. I know its possible but that person who knows is not ready to tell how. Its Urgent. There is some Google link for it PLZZ tell how step by step Rgds,

I have forgotten the password or username for my Google account, or I'm unable to access my account for other reasons.  How can I recover my account?  (This Q&A is meant as a general description for all Google and Gmail username/password questions. See: )


My next plan is to live (travel) in the UK within 6 months. As a Taiwanese national, we don't have to apply for a visa if our stay is within 6 months, however, we need to prepare documents so basically my question is about the documents.   How much money do I need in my bank account if I am planning to stay for 4 months? Could I use a train ticket to France or a plane ticket to France rather than a return ticket to Taiwan? My real plan is to be a nomad in the UK, but I don't want to complicate things for the officer in the airport, could I just simplify my schedule (pretend to be a one month visit in the UK? How could I prepare the accommodation proof if I am going to use couchsurfing for 80 percent of the time while staying in the UK?

Many of the UK visa refusals we see here share a common pattern and the prevailing reasons refer to V 4.2 (a) and (c).    I do understand that, while the applicants may describe very different individual circumstances, there's a consistent pattern and, broadly, fall into specific categories:    Credibility (lifestyle, lack of ties, visit history, lies & omissions) Funding (insufficient funds, provenance of funds, funds parking) Sponsorship (family, friends, employer)   Question: What most commonly triggers a UK visa refusal where V 4.2 (a) and (c) are given as the grounds?  Secondarily: Given that there is a clear pattern, to what extent are these refusals predictable? Does sponsorship make a difference? Is there a set of personal circumstances, however abstract, where a refusal is all but guaranteed? For example, why do those we see here on TSE who sought entry for the PLAB or British Army appear to be refused with a common theme? Is there a uniform shortcoming or is it just discrimination?   PLAB: What is about applications for a visa, for the purpose of sitting the Professional and Linguistic Assessments Board (PLAB) exam, that seem to invite refusals. After all, the test is given so that international medical graduates can show that they qualify to practise medicine in the UK. The first part, PLAB 1, can be taken in centres outside of the UK. However, PLAB 2 can be taken only in the UK. Why can't you can't get a visa just to sit the exam, promising that you'll leave immediately after?    British Army: Since Commonwealth citizens are eligible to apply online to join, even those who don't reside in the UK, why is it so difficult to get a visa just to attend an interview to see whether you are suitable? Even with an invitation from the Army, such visa applications seem to be unsuccessful. Isn't a career in the British Army a valid reason?     Lastly:  After such a refusal, what approaches would increase the chance of a successful application?


I'm going over an old homework question in my Analysis class that I missed. My professor's solution was confusing so I am looking for additional help.  The question is: If $\{p_n\}_{n \in \mathbb{N}} $ is a cauchy sequence in a metric space, show that for any $\epsilon > 0$ there exists a subsequence $p_{n_i}$ such that $d(p_{n_i}, p_{n_{i+1}}) < \frac{\epsilon}{2^{i+1}}$.  My solution was to choose $p_{n_1}$ and $p_{n_2}$ such that $d(p_{n_1}, p_{n_2}) < \frac{\epsilon}{4}$ and then choose $p_{n_j}$ for $j \geq 2$ such that $d(p_{n_j}, p_{n_{j+1}}) < \frac{\epsilon}{2^{j+1}}$ which we can do since the sequence is Cauchy.  If you could explain how to do it and why my solution doesn't work, that would be much appreciated. Thanks in advance.

Let $(X,d)$ be a metric space and $(a_n)$ a Cauchy sequence in $X$. How to show that there exists $n_1<n_2<\cdots$ such that $$d(a_{n_{i+1}},a_{n_i})<2^{-i},$$ for all $i\in\mathbb{N}$?  I tried to use induction, but it doesn't work. The base case is OK, but if we have $$d(a_{n_2},a_{n_1})<2^{-1},\ldots,d(a_{n_k},a_{n_{k-1}})<2^{-(k-1)},$$ I don't see any reason for to exist $n_{k+1}>n_k$ such that $d(a_{n_{k+1}},a_{n_k})<2^{-k}$.


Came across this article today:  which had the following sentence:  No-one has been arrested and the motive for the shooting is unclear.  screengrab:  I've never seen no one hyphenated like this before. I even had to read it twice just to get it. Why hyphenate no one: no-one?

What is the correct form? Does context play a role?  Are there noticeable trends towards the awkward "noone" or is it just a by-product of careless orthography on the Internet?


I am not sure how to prove that if $n$ is odd then the square of $n$ has a remainder of $1$ when divided by $8$.

If $x$ is odd then prove that $x^2-1$ is divisible by $8$.   I start by writing: $x = 2k+1 $  where $k\in\mathbb{N}$.  Then it follows that: $(2k+1)^2 -1 = 4k^2 +4k + 1 -1 $    Therefore: $$\frac{4k^2 +4k}{8} = \frac{k(k+1)}{2}$$  At the end part I can see that for what $k$ is, the number on top is divisible by 2. I was expecting the end result to be a number, not a fraction. Or is it "divisible" from the definition $\text{even} = 2k$ that completes the proof?


Why is it wrong to serial voteup someone you like his answers?  Sometimes I just came to stackoverflow to read certain people answers(there are 4 guys currently) I have their profile bookmarked in my browser and in my free time at office I go to their profile and read their answers and learn a lot from them, but because I'm afraid to be a serial voter, I dont voteup them.   I think there is nothing wrong with that, if there is, please let me know.

I am not a fraud, I have no acquaintances here whatsoever. I love reading questions and answers here and upvoting what I feel is cool. Sometimes I'm in awe of some answers and questions posted here. So I do see into users' profile and open their top questions and answers, and if I like them I upvote.   Number of votes:  Mostly up to 5 questions or answers (may be at best 10).   Mode:  When upvoting (or downvoting) in the opened links, I do not restrict my votes just to that user, but to all good answers and questions I find in that link. Also I do not open the profiles of someone I remember I had visited once.   Am I susceptible to be caught for serial voting? Is reputation gained from my votes deducted from his profile in this scenario? I just don't want my votes to be wasted, hence asking.. I went through  two  but hadn't got enough clarification.


How many Hamiltonian circuits are there in a complete graph with n vertices? [duplicate]

It seems to me like the answer should be $n!$. Since you can first select the first vertex, then select each remaining vertex until you've got them all in a permutation.  My textbook, however, says that the answer is $(1/2)(n-1)!$  Unfortunately, it doesn't explain why this is. Why is it?


how do I RDP to Ubuntu 16.04 from windows?

I want to connect Ubuntu LTS via windows7 RDP. Is there any other settings these settings are not working.


I'm building a website's with realtime events happening, this is my tech stack:  Language: PHP Framework: Laravel  I'm using a self hosted websockets. We're expecting 3,000 users will use the website at the same time. I want to know if our server can handle 3,000 concurrent users using the website at the same time, meaning there are 3,000 open websokets. How can I know if the server can handle this? This is the specs of our dedicated server: Intel Dual Xeon E5-2620 v4, 16 cores 64 GB Ram 3,707GB SATA in RAID105TB

This is a  about capacity planning for web sites. Related:      What are some recommended tools and methods of capacity planning for web sites and web-applications? Please feel free to describe different tools and techniques for different web-servers, frameworks, etc., as well as best-practices that apply to web servers in general.


I am looking into modeling some realistic houses/buildings as a collection.  This is also one of the few times google images has failed me.  I can't seem to find helpful reference images and building plans. Anyone know of a good place to find these? www.the-blueprints.com/ sadly has no category for buildings.  Thanks

I'm a newbie.  I've gone through a number of tutorials and want to get some actual experience with modeling. But, I don't know where to go to get good reference images for modeling with front/sides views.  Can anyone recommend the best places to find such images?


I have windows 7 and want to install ubuntu alongside it. I have a 1tb hard drive and when I go into disk management it says by c drive (I only have one drive) has 670gb of free space. I want to shrink 132gb for ubuntu but on the window where I choose how much I want to shrink it says "Size of available shrink space in MB: 30885" which is about 30gb. The there is a message at the bottom of the window that says "You cannot shrink a volume beyond the point where any unmovable files are located. See the "defrag" event in the Application log for detailed information about the operation when it was completed."  Does this mean I can only reserve at most 30gb for ubuntu even though I have 670gb of free space on my c drive, is there any way to fix this without reinstalling windows 7?

What I am trying to accomplish is to shrink my C drive by 50 GB and make that 50 GB into a new partition to install windows 8 on.   In Disk Management it shows I have Disk 0 with 4 partitions :    SYSTEM (199 MB) C (909 GB) Recovery (D) (21 GB) HP_TOOLS (102 MB).    (Unfortunately I cant include the picture because I dont have 10 rep on this site).   And the issue I have is that when I right click on C to shrink the partition it says that the shrink space available is only 297 MB, when at the top of the screen it indicates that C has 472 GB of free space. Why is it not allowing me to shrink more than 297 MB?


Is it possible to disable this feature? The web page I am visiting requires that I only use ASCII characters.

Possible Duplicate:          I installed the IE10 beta on Windows 7. It has an annoying autocorrect feature like the one in MS Word that messes up everything I write. How do I disable it?


So I need to find the names and sizes of all the files in a certain folder (finding out the number of files in the folder is not necessary).  How would this be done and would I need to put the program in the same folder as the files I'm trying to find the name and size of?  Thanks in advance for your help!

How can I determine the list of files in a directory from inside my C or C++ code?  I'm not allowed to execute the ls command and parse the results from within my program.


Why does the following code return an empty array as a result ([])?  $('#non-existing-id').first();   I thought that it should return null or undefined.  How can I check for the success then? I don't see anything about it in the documentation.

In Mootools, I'd just run if ($('target')) { ... }.  Does if ($('#target')) { ... } in jQuery work the same way?


I just finished an intro course in cryptography and I found it very interesting and want to pursue it further. I wanted some intermediate-level books and resources which will deepen my knowledge of this subject. Specifically, I want to read about  stream ciphers randomness, hash functions design considerations (how symmetric and asymmetric systems are designed) cryptanalysis  Preferably, I would not want references too terse or rigorous in math but neither too computer science-y. Our class followed the book Introduction to Cryptography: With Coding Theory (Trappe, Washington) and I really liked the approach of the book and would want similar resources (in terms of how they approach topics). Any help would be appreciated.

I successfully ended the book Elementary Number Theory by David M. Burton. It is a great book on Number Theory and History of Number Theory. Specially, I loved the concise chapter on Cryptography. Now, I am pretty interested to continue my study in Cryptography. Which books or websites should I read to learn more on Cryptography, if there is more math of it?


I been looking into group_concat, but it isn't working on SQL 2012, From what i have figured is that i have to have a functions to do so. But here is my question, i'm sending a SQLQuery by some c# code and want to return a datatabel.   '001' '123' '456' (and keep on going until we cannot find anymore phone number that is attached to the Cosnr.   From what i get now is. '001' 123' '001' 345'  Is there anyway, to send a single SQLQuery form C# to get back a datatabel looking like  '001' '123' '456'  Hope anyone can help me. :)

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


I remember reading a young adult novel in the '90s about a girl traveling on a spaceship. If I recall correctly, there's a dangerous race of aliens who can disguise themselves as humans, and she discovers that one of them is on the ship with her. She somehow ends up inside the walls of the spaceship, I believe in order to spy on the alien, and I think it ends up pursuing her through the walls toward the end of the book. Anybody know what it could be?

I read this book once when I was in middle school. A girl solves a murder or a mystery on a spaceship. It was a thin paperback books.   All I can remember is that there was an alien, and there was a movie star or actress or famous makeup artist on the ship traveling with another woman. By the end of the book the murderer was the woman the actress was traveling with who forced her to use her makeup skills to disguise her, and she was really some kind of alien.


let $ f_{n}:[a,b]\to\mathbb{R} $ be a sequence of increasing and continuous functions (each function is continuous and increasing, it dosent mean that the sequence is increasing). And assume that exists $ f:[a,b]\to\mathbb{R} $ such that $ f $ is continuous and  $ f_{n}\to f $ pointwise. I have to prove that the convergence is also uniformly. I tried to  assume by contradiction that there is no uniformly convergence, but I got stuck. Now I have a new intuitio, since $ f_n $ and $ f $ are continious in $ [a,b] $ they are uniformly continuous. so actually for any $ x $ I can write: $ |f_{n}\left(x\right)-f\left(x\right)|\leq|f_{n}\left(x\right)-f_{n}\left(x+\delta\right)|+|f\left(x\right)-f\left(x+\delta\right)|+|f_{n}\left(x+\delta\right)-f_{n}\left(x+\delta\right)| $ Where $ \delta $ would fit to some $ \varepsilon $ from the unifromly continuous definition, where the first two terms can be small as I want, I can continue with it untill $ x+k\delta $ "is close enough" to $ b $  where $ k \in \mathbb{R} $. But again, Im not sure how to do it since $ \delta $ would have to depend on $ n $. Any hints would help. Thanks in advance

I'm reading some extreme value theory and in particular regular variation in Resnick's 1987 book Extreme Values, Regular Variation, and Point Processes, and several times he has claimed uniform convergence of a sequence of functions because "monotone functions are converging pointwise to a continuous limit". I am finding this reasoning a little dubious.  EDIT: Thanks to some comments below I realized I was confused, I really want each $f_n$ to be a monotone function on $[a,b]$, so it isn't quite like Dini's theorem. Formally I am wondering:  Let $f_n:[a,b]\rightarrow\mathbb{R}$ be a sequence of non-decreasing functions converging pointwise to the continuous function $f$. Is the convergence uniform?   My thoughts:   I have been thinking that since the set of discontinuities of each function $f_n$ is at most countable, the set of discontinuities of the entire sequence is at most countable...something something? Any thoughts would be greatly appreciated!


When I put my DVD-ROM and select the option to install Ubuntu, a black screen appears that says: Couldn't get size: 0x800000000000e MODSIGN: Couldn't get UEFI db list Couldn't get size: 0x800000000000e    All the answers that I found on the internet were talking about disabling Secure Boot, but my motherboard doesn't support UEFI, so I don't have this option. What should I do?

Problem on a Mac Mini Mid 2011. I have looked through other articles and couldn't get help. Any help?


I've seen similar cases but I can't seem to figure it how on my case.  So I got 3 different divs all having the same class of "display-boxes". What I'm trying to do is to apply my functions for all 3 divs. At the moment it's only applying the function for the last div.  $(".display-boxes").each(function() {   var boxList = $(this).context;    function resizeTeasersTablet(teaserNumber, teaserCollection) {     if (teaserNumber == 1) {       teaserCollection[0].style.width = '73.834%';       teaserCollection[0].style.margin = '0 auto 40px';       for (let i = 1; i < teaserNumber; i++) {         teaserCollection[i].style.width = '25%';       }     } else if (teaserNumber == 2) {       for (let i = 0; i < teaserNumber; i++) {         teaserCollection[i].style.width = '50%';       }     } else if (teaserNumber == 4) {       for (let i = 0; i < teaserNumber; i++) {         teaserCollection[i].style.width = '50%';       }     } else if (teaserNumber == 5) {       for (let i = 0; i < teaserNumber; i++) {         teaserCollection[i].style.width = '50%';       }     } else if (teaserNumber == 3) {       for (let i = 0; i < teaserNumber; i++) {         teaserCollection[i].style.width = '33.33%';       }     }   }    function resizeTeasersMobile(teaserNumber, teaserCollection) {     for (let i = 0; i < teaserNumber; i++) {       teaserCollection[i].style.width = '100%';     }   }    document.addEventListener('DOMContentLoaded', function() {     if (window.innerWidth > 2024) {       displayTeasers(boxList.childElementCount, boxList.children);     } else if (window.innerWidth > 641) {       resizeTeasersTablet(boxList.childElementCount, boxList.children);     } else {       resizeTeasersMobile(boxList.childElementCount, boxList.children);     }   });    window.onresize = function() {     if (window.innerWidth > 2024) {       displayTeasers(boxList.childElementCount, boxList.children);     } else if (window.innerWidth > 641) {       resizeTeasersTablet(boxList.childElementCount, boxList.children);     } else {       resizeTeasersMobile(boxList.childElementCount, boxList.children);     }   }; });

                                      @@MarkComponentField(FieldPath+".Teaser_Image")@@

     This is one of the 3 divs that I have since it won't let me post more code.

I have a bit of code where I am looping through all the select boxes on a page and binding a .hover event to them to do a bit of twiddling with their width on mouse on/off.  This happens on page ready and works just fine.  The problem I have is that any select boxes I add via Ajax or DOM after the initial loop won't have the event bound.  I have found this plugin (), but before I add another 5k to my pages with a plugin, I want to see if anyone knows a way to do this, either with jQuery directly or by another option.


In , it can be seen that using a luck point when doing something at a disadvantage essentially transforms it into super-advantage.  Does this specific strategy still works when throwing a net (which, by default, are always at a disadvantage due to their 5ft short range) ?

If I have the Lucky feat1, it allows me to choose to take a re-roll, to see if I might do better on a d20 check:  Whenever you make an attack roll, an ability check, or a saving throw, you can spend one luck point to roll an additional d20. You can choose to spend one of your luck points after you roll the die, but before the outcome is determined. You choose which of the d20s is used for the attack roll, ability check, or saving throw.  So in the chance of a disadvantaged roll, I can choose to attempt a better roll; but if the outcome is still worse, it does not expend a "luck point", should I choose. Is this the case?  1 Not to be confused with the Halfling's racial trait also called Lucky that works somewhat differently.


In this post I posted comment in response to another. In the post, I tagged someone's username, but in its possessive form. I put a space in between the username and the apostrophe, because I wasn't sure if the username tag would disappear if an apostrophe and an s was added.   I know this is a tiny problem, that can easily be avoided, but I'd like to know. Are there algorithms in place that keeps the tag in place even though an apostrophe and an s is added?

How do the comment replies (aka "pinging users") work?  Who can I send an @reply to? How do I respond to a specific user when entering my comment? Will they be notified? What do people mean when they talk about "pinging" another user?  Related:


The Room of Requirement is extremely useful, but Harry barely uses it. Sure the DA uses it, and so does Harry to hide his Potions book, but for half of the fifth book, and the sixth, whenever he needed anything (minus food) the room would bring it to them. So if he was worried about his O.W.Ls, then he could tell the room to help him out. Or if he wanted a secret passage to Grimmauld Place, he could use the room, instead of sneaking into Umbridge's office.   This is not asking what the room's limits are, but asking why Harry doesn't frequently use it.

Can the Room of Requirement provide anything if needed? For example:   James Potter wanted to hide from Voldemort, it would have served as a perfect hiding place. Harry Potter wanted all the Hocruxes, he should have gone straight to the room of requirement where he would have found all the Hocruxes along with the Sword. All the muggle borns of the wizarding community could have taken refuge in the room of requirement. Can someone meet a dead person in the room of Requirement if needed? Would it have been possible for Harry to go in past in order to see Dumbledore for the explanation of many things? Can the room duplicate something? For instance, Harry needed the Elder wand; with Voldemort having it, could he still get it? Someone wishes to be knowledgeable than Dumbledore, would the seeker find his desired wish by finding books and things?   Who created the room of requirement (surely not Salazar)? Was it beyond Dumbledore's magic to create such a place?


In opened msconfig.exe window, General tab, I set the startup selection to Diagnostic startup. After rebooting system windows didn't boot, even in safe boot. Operation system is Windows 7. How can i resolve it?

I have a HP-G62 B17S laptop, which has Windows 7 Home Edition 64-bit.  I read on a blog about a setting in msconfig.exe (Windows System Configuration utility):     Boot > Advanced options > Number of Processors   This was showing 1 for me but I have a dual core AMD Turion, so I changed the setting to 2. Next to it was a Maximum Memory setting (which was unchecked). I checked it and made sure it was max 4096; my system has 4GB RAM.  After restarting the laptop, it now gives an error:     Windows Error Recovery   Windows failed to start   I can choose from two options:   Launch Startup Repair Start Windows normally.   When I select Startup repair, it goes on to give another error:     Windows Boot Manager       Windows failed to start. A recent hardware or software change might be the cause. To fix the problem:         Insert your Windows installation disc and restart your computer.    Choose your language settings, and then click "Next."     Click "repair your computer."      I do not have the Windows installation disc for this OS version - the manufacturer did not send it to me when I purchased the laptop.  If I try to start Windows normally it takes some time and then gives the same error message.  I tried inserting another installation disc of Windows 7 Professional Edition 64-bit (available from my other laptop), and restarting, but no repair menu comes up.  I also tried restarting the laptop, pressing F8 to enter Advanced Startup Options and selecting to boot with the Last known good configuration, or starting in safe mode - neither option gives any success. This time it gives a Blue Screen of Death with the following message:     A problem has been detected, and Windows has been shut down to prevent damage to your computer - BAD_SYSTEM_CONFIG_INFO   It then does a crash dump of the memory and restarts with the same options of repairing or starting Windows normally as earlier.   What exactly seems to be the problem here and its cause? What are my options now to restore/repair my Windows 7 OS to a working condition? Would the manufacturer send a recovery/repair disk for this if I called them? The laptop should be in warranty period - it was purchased six months ago. I have a Ubuntu 10.04 bootable CD. Is there any way to boot into Ubuntu, and repair Windows from there? Are there any other way to recover the OS? (I have an access to a working Windows Vista HP Laptop, if that helps)   EDIT Ok, it was able to boot through the Win-7 professional Installation disc, but even after doing Startup repair, and System restore, It still does not boot into the original Win-7.


I was talking about this with a friend yesterday, though the actual example was "thou and I", which sounded weird. I thought it should be "thee and I", due to "I" being a subject pronoun. I eventually conceded, but I'm still not sure - could you say (arguably) that "thou/you", when paired with "I", is an object? Or are they still both subjects?  Similarly, is "it" still the subject in a sentence like "the dog and it"?

From some comments in the answers for  (now deleted, 10k only), there's confusion around the usage of I vs. me:  While the sentence, "the other attendees are myself and Steve," is agreed to be incorrect, there's confusion about whether the correct form is "the other attendees are me and Steve" or "the other attendees are Steve and I."  (I've always used the heuristic of removing the other people from the sentence, so I always thought "the other attendee is me" would be correct, instead of "the other attendee is I." Is this true, or am I using a flawed heuristic?)


Let's say I want to have a server with as many user accounts as possible. How many is the max?   I want millions of user accounts. Is that crazy? I'd host dozens of load-balance mirrors of the box, and user data would be stored on a highly available storage share, while all other data is assumed to be volatile.

What is the maximum number of users accounts I can have on Linux?


I am trying to find such a function or a proof, which shows that there is no such function in general. I know, that the other direction of this statement is true. (I prooved it using only the definiton). But here I have no idea, how to show it. Thank you

So I had an exam today and one of the questions were: Give an example of a function $f$ which is nowhere continuous but $|f|$ should be continuous at all points. At first I had no idea how to do it then I came up with this, even though I know it's wrong:  $$f(x)= \begin {cases} \ \sqrt{x}&\text{if }x <0\\ \sqrt{-x}\ &\text{if }x > 0\\ \end {cases}$$  Like I said I know it's wrong..but can someone give me an example of this? Thanks.


I recently tweaked some Notepad++ settings and I somehow turned off the icons for folding code blocks. Whenever I open a JavaScript or C# file now, the collapse code block icons that are located off to the left side are missing. How can I turn them back on?

Is it possible to get rid of the function folding margin on Notepad++? It seems like the sort of thing that should be in the prefs but I'm not seeing it anywhere.


Suppose $K$ is a field which is not algebraically closed. Given any natural number $n$ how can I construct a  polynomial in $n$ variables whose zero set in $K^n$ is $(0,\ldots,0) (n-tuple).$  Give me some hint. Will characteristic play a role here ?

I am trying to prove the following statement.     If a field $K$ is not algebraically closed, then any $K$-variety $V\subset\mathbb{A}^n$ can be written as the zero set of a single polynomial in $K[X_1,X_2,...,X_n].$     Suppose $V=V(f_1,f_2,...,f_n)$, and I would want to find a polynomial $g\in K[X_1,X_2,...,X_n]$ such that $V=V(g)$.  I know that if I can find a polynomial $\phi\in K[X_1,X_2,...,X_n]$ whose only zero is $(0,0,...,0)$, then it is done, since we could take $g=\phi(f_1,f_2,...,f_n)$.  For $n=1$, then I would just choose $\phi=X$, but I do not even know how to proceed to the case $n=2$. Maybe we could choose an irreducible polynomial of degree $>1$.  Any help will be appreciated.


You write a quick answer and post it. You write an answer, post it and then OP updates the question You accidentally post the question/answer before it's ready   All these cases have one thing frequently in common:    A storm of downvotes   It has happened to everyone. And frequently, those downvoting people don't even read your updated answer - they've already moved on.  Now, I'm not even trying to go into the whole "obligatory downvote explanation" story, but rather I'd like suggest a way to prevent this.  Do you think it might be a good idea to add a timer before something freshly posted can be downvoted? 30 seconds, 1 minute... Whatever would work the best.

There needs to be a timer or something on upvoting/downvoting.  I posted an answer to a question and as soon as the page loaded, my answer was already down voted. There is no way someone had the time to read the answer < 10 seconds after it was posted.


Can I publish desktop application has developed in Lazarus IDE in Ubuntu Software Center?

I have a project which enable to execute commands with the voice, .  How can I publish it on the ubuntu's software center?


I have a recent Dell XPS and I installed Linux on it. I now wish to install Windows inside a VM but there is no license key anywhere on the laptop or in the box. All of the answers I can see say its embedded in the bios but I don't see any way the Windows in a VM could access this. Is there any way to get the windows key without windows currently installed?

Context Three years ago my company got me a Lenovo T550 with Windows 10 Home installed on it (my understanding is that this is called "OEM"). I immediately erased everything to install Ubuntu on it. Unfortunately from now on I will need to use Windows 10 a few times a week for legacy reasons, but my main work is still on Ubuntu, so I am thinking of running Windows 10 within VirtualBox within Ubuntu. Lenovo recommendation Lenovo told me that my Windows Home license is somehow linked to my hardware (firmware?) and that Windows will automatically find this out. They pointed me to :  The installation of Microsoft Windows Server 2008,2008 R2 SP1, 2012, and 2012 R2 from Lenovo OEM media to such a virtual machine will fail until the virtual BIOS has been updated to include this information. setVMBIOS.exe performs this function for servers using Microsoft Hyper-V technology. Consult your hypervisor vendor for information on how to perform this function on other hypervisors. [...] The fix resolves this issue by adding Lenovo information to the virtual BIOS.  Note: That page does not mention Windows 10 Home, but I guess the same applies? VirtualBox How to apply Lenovo's recommendation to VirtualBox? (5.2.18) Right now I have out-of-the-box VirtualBox and the VM I created yesterday with standard settings does not activate:   Windows is not activated. Windows reported that no product key was found on your device. Error code: 0xC004F213


I dynamically create multiple textboxes for showing information to the user. Now I want to set the back- and forecolor of some textboxes if a statement is true.  All this works just fine, untill I disable the textbox, now the forecolor "resets" to the standart color instead of showing my desired one.  DataTable dt = [some data] //Col 0: ID //Col 1: some text //Col 2: date  for (int i = 0; i < dt.Rows.Count; i++) {      DateTime d = (DateTime) dt.Rows[i].ItemArray[2];     TextBox txt = new TextBox();     txt.Multiline = true;     txt.Font = tb_Aufloesung.Font;     txt.Text = dt.Rows[i].ItemArray[1].ToString() + "\n" + d.ToString(@"dd.MM.yyyy");     txt.Size = new Size((TextRenderer.MeasureText(dt.Rows[i].ItemArray[1].ToString(), txt.Font).Width) + 10, 34);     txt.Location = new Point(43, 3 + split.Panel2.Controls.Count / 2 * 40);      if(d <= DateTime.Now) {         txt.BackColor = Color.Red;         txt.ForeColor = Color.White;     }          //txt.Enabled = false;      split.Panel2.Controls.Add(txt); }   This is how the Textboxes look when I use the code above with :   comment the line   -> //txt.Enabled = false; uncomment the line -> txt.Enabled = false;     I have no idea why in the second case, the forecolor of the red textbox is not white as it should be. Anyone any idea?

Does anyone know which property sets the text color for disabled control?  I have to display some text in a disabled TextBox and I want to set its color to black.


I have a position space wavefunction $$\psi(x) = \delta(x-a) + \delta(x+a).$$ Now the question states to compute the following:    The Fourier transform of $\psi(x)$. (Which invariably is the momentum space wave function $\phi(p)$) Compute $\Delta p \Delta x$   Now to compute $\phi(p)$ one first need to normalize $\psi(x)$, but while doing so, one need to compute, $$|N|^2\int\limits_{-\infty}^{+\infty}  (\delta(x-a) + \delta(x+a))^2 dx =1,$$ $N$ being the normalization constant. But my question is how to go about computing this integral?  The normalization integral is now done, any help, in solving $\Delta x$, or $\Delta p$? I can't see through this problem?

In Griffiths' Intro to QM [1] he gives the eigenfunctions of the Hermitian operator $\hat{x}=x$ as being   $$g_{\lambda}\left(x\right)~=~B_{\lambda}\delta\left(x-\lambda\right)$$  (cf. last formula on p. 101). He then says that these eigenfunctions are not square integrable because   $$\int_{-\infty}^{\infty}g_{\lambda}\left(x\right)^{*}g_{\lambda}\left(x\right)dx ~=~\left|B_{\lambda}\right|^{2}\int_{-\infty}^{\infty}\delta\left(x-\lambda\right)\delta\left(x-\lambda\right)dx ~=~\left|B_{\lambda}\right|^{2}\delta\left(\lambda-\lambda\right) ~\rightarrow~\infty$$  (cf. second formula on p. 102). My question is, how does he arrive at the final term, more specifically, where does the $\delta\left(\lambda-\lambda\right)$ bit come from?   My total knowledge of the Dirac delta function was gleaned earlier on in Griffiths and extends to just about understanding   $$\tag{2.95}\int_{-\infty}^{\infty}f\left(x\right)\delta\left(x-a\right)dx~=~f\left(a\right)$$  (cf. second formula on p. 53).  References:   D.J. Griffiths, Introduction to Quantum Mechanics, (1995) p. 101-102.


Recently I have come across instances of moderators being biased and trying to stifle the discussion through their special privileges on Stack Exchange sites (especially if the point of view or discussion is against their own personal views and they are involved in it). The problem is that there are many policies about what can be posted and what is not allowed which can be interpreted and justified by a moderator in his/her favor as those are quite subjective and open to interpretation. They use those policies as an excuse to close discussions or hinder users who they might have a personal bias against due to some past interactions. What can be done to mitigate this problem and what steps can a normal user take to discourage such kind of behavior?

One or more of the following things happened to me on a Stack Exchange site:   My post(s) were wrongly deleted or locked by a moderator A moderator posted a wrong comment on one of my posts I was suspended, but did not do anything wrong I asked a meta question, but the question was closed and/or deleted A moderator discredited me in public ...   I think a moderator has abused their power, but I feel powerless against them.  What recourse do I have now? What can I do when I feel that a moderator has abused their power, and has been repeatedly unfair in their dealings with me?


In the derivation of energy conservation, there is the transformation $q(t)\rightarrow q'(t)=q(t+\epsilon)$, whose end points are kind of fuzzy. The original path $q(t)$ is only defined from $t_1$ to $t_2$. If this transformation rule is imposed, $q'(t_2-\epsilon)=q(t_2)$ to $q'(t_2)=q(t_2+\epsilon)$ is not defined in the original path. Then how could the Lagrangian be integrated?  On P.98 of Jakob Schwichtenberg's book Physics from Symmetry, he stated that $\delta q(t_1)=\delta q(t_2)=0$ whereas Kleinert stated in his Particles and Quantum Fields $\delta q_s(t_a)$ and $\delta q_s(t_b)$ are not necessarily $0$. Who's correct?  This question is different from the endpoint questions since it is already clear that $q(t_2+\epsilon)\neq q(t_2)$.

I was reading about symmetry of action when I came before the symmetry variation in Particles and Quantum Fields by H. Kleinert; there he wrote:     Symmetry variations must not be confused with ordinary variations $\delta q(t)$ used to derive the Euler-Lagrange equations. While the ordinary variations   $\delta q(t)$ vanish at initial and final times, $\delta q(t_b) = \delta q(t_a) = 0,$ the symmetry variations $\delta_s q(t)$ are usually non-zero at the ends.   So, isn't $\delta_s q$ a virtual variation? For, if it would be, it should have vanished in the fixed initial and final time, $t_a$  and $t_b$, isn't it?  Could anyone explain me why the symmetry  variation is different from the ordinary variation?


Input. Let's say I have a file named f with the following content:  +% H % V   I can get the first column sorted in two ways:  First approach:  cat f | awk '{print $1}' | sort   Second approach:  cat f | sort -k 1 | awk '{print $1}'   Output & Question. It seems to me that it must be the same results, but it isn't: the output of the first command is:  % +%   and of the second is:  +% %   If I swap H and V in the second column of file output of the second command would change, but it shouldn't. Flag for stable sort doesn't change anything. All these were tested for bash versions:  GNU bash, version 4.3.11(1)-release (x86_64-pc-linux-gnu)  and  GNU bash, version 3.2.25(1)-release (x86_64-redhat-linux-gnu).  So, my question is why do outputs differ?

Using the same sort command with the same input produces different results on different machines.  How do I fix that?


I have a asp:GridView and it has a asp:BoundField that contains DateTime data comming form database. now here i want to show this DateTime to my local GMT DateTime only for view purpose.  I think it should need a client side solution.  source is below,   <asp:BoundField HeaderText="Registration Date" DataField="RegisteredDate" DataFormatString="{0:MM/dd/yyyy hh:mm:ss}" />   here RegisteredDate is the CurrentDateTime from database under DataField  Any help will be appreciated.

We are developing a C# application for a web-service client. This will run on Windows XP PC's.  One of the fields returned by the web service is a DateTime field. The server returns a field in GMT format i.e. with a "Z" at the end.  However, we found that .NET seems to do some kind of implicit conversion and the time was always 12 hours out.  The following code sample resolves this to some extent in that the 12 hour difference has gone but it makes no allowance for NZ daylight saving.  CultureInfo ci = new CultureInfo("en-NZ"); string date = "Web service date".ToString("R", ci); DateTime convertedDate = DateTime.Parse(date);               As per :     UTC/GMT Offset       Standard time zone: UTC/GMT +12 hours   Daylight saving time: +1 hour   Current time zone offset: UTC/GMT +13 hours     How do we adjust for the extra hour? Can this be done programmatically or is this some kind of setting on the PC's?


I'm doing Exercise 13 in textbook Algebra by Saunders MacLane and Garrett Birkhoff.   If $F$ is a finite field, prove that every function in $F^{F}$ is a polynomial function.  Could you please verify if my understanding is correct? Thank you so much for your help!  Assume $F = \{a_1,\cdots, a_n\}$ and $f \in F^F$. We define a polynomial $p \in F[x]$ by $$p = \sum_{i=1}^n f(a_i) \frac{\prod_{j \neq i} (x-a_j)}{\prod_{j \neq i} (a_i-a_j)}$$ Because the sum and product are finite, they are well-defined. Then we can verify that $f$ is the polynomial function induced by $p$. This completes the proof.

From a bank of past master's exams I am going through:     Let $F$ be a finite field. Show that any function from $F$ to $F$ is a polynomial function.   I know that finite fields are fields of $p$ elements for $p$ prime [EDIT: It's actually $p^n$ for $p$ prime; see comment below]. Since I have $p$ choices for the $p$ elements to map to, then I have $p^p$ distinct functions. I think every function can be written in the form $f(x) = a_{p-1}x^{p-1} + \dots + a_0x^0$. For then given the values $f(0), f(1), \ldots f(p-1)$, I can solve for the coefficents by the linear system of equations  $$ a_0 + \sum_{i=1}^{p-1} n^i a_i = f(n).$$  This then gives me a $p-1 \times p-1$ square matrix over the field $\mathbb{F}_p$:  $$\left( \begin{array}{ccccc} 1& 0 & 0 & \ldots & 0 \\ 1& 1 & 1 & \dots & 1 \\ 1& 2 & 4 & \dots & 2^{p-1} \\ \vdots & \vdots & \vdots & & \vdots \\ 1 & p-1 & (p-1)^2 & \dots & (p-1)^{p-1} \end{array} \right) \left( \begin{array}{c} a_0 \\ a_1 \\ a_2 \\ \vdots \\ a_{p-1} \end{array}\right)  = \left( \begin{array}{c} f(0) \\ f(1) \\ f(2) \\ \vdots \\ f(p-1) \end{array} \right)$$  If I can show this matrix is invertible, then I can always find the $a_i$. But I am a bit stumped on how to show this (partially because I don't think I've ever done linear algebra in a vector space over a finite field). It does not seem easy to show linear independence, or nonzero determinant, or full row rank.    Alternatively (I just thought of this), can I show this is true by arguing that the map between the two sets (the set of polynomials of degree $p-1$; and the set of functions $F \to F$) is injective, and that it must be a bijection because the sets have the same cardinality $p^p$?


I have the following class BallotPaper, which records a set of votes in a LinkedList:  import java.util.LinkedList;  public class BallotPaper {      private LinkedList<String> votes;      public BallotPaper() {      }      public void addVote(String candidateName) {         votes.add(candidateName);     }      public LinkedList<String> getVotes() {         return votes;     }  }   I have a text file which contains a list of votes, which looks like the following:  John Jack James Fred John Jack James Fred Fred Jack John James Fred Jack John James Jack John James Fred   In my main class, I have an ArrayList of BallotPaper objects. Each line in the text file compromises of four names, which each need to be added to a single BallotPaper object, then stored in the ArrayList. Here is my code to read the text file:  private ArrayList<BallotPaper> votes = new ArrayList<>();  public void readTextFile(String fileLocation) throws FileNotFoundException {     FileInputStream fileIn = new FileInputStream(fileLocation);     Scanner scanner = new Scanner(fileIn);      while(scanner.hasNextLine()) {         votes.add(new BallotPaper());         for(int i=0; i<4; i++) {             String name = scanner.next().trim();             if(!name.equals("")) {                 votes.get(votes.size() - 1).addVote(name);             }         }     } }   So my goal is for the ArrayList to contain 5 elements, each of which are BallotPaper objects with 4 entries in their respective LinkedList. I am currently getting the following error:  Exception in thread "main" java.lang.NullPointerException     at BallotPaper.addVote(BallotPaper.java:12)     at Model.readTextFile(AVSModel.java:50)

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


Let $x$ have a uniform density  $f_x(x\mid\theta) \sim U(0,\theta)=\left\{     \begin{array}{ll}         \frac{1}{\theta} & 0 \leq x \leq \theta \\         0 & \text{otherwise}     \end{array} \right.$  If there are $n$ samples $D=\{x_1,x_2,...,x_n\}$ drawn independently according to $f_x(x\mid\theta)$; then:  How can I show that the maximum likelihood of $\theta$ is $\max[D]$?

There is a classic problem:  Suppose that $X_1,\ldots,X_n$ form an i.i.d. sample from a uniform distribution on the interval $(0,\theta)$, where $\theta>0$ is unknown. I would like to find the MLE of $\theta$.  The pdf of each observation will have the form: $$ f(x\mid\theta) =  \begin{cases} 1/\theta\quad&\text{for }\, 0\leq x\leq \theta\\ 0 &\text{otherwise}. \end{cases} $$ The likelihood function therefore has the form: $$ L(\theta) = \begin{cases} 1/\theta^n \quad&\text{for }\; 0\leq x_i \leq \theta\;\; \text{for all }i,\\ 0 &\text{otherwise}. \end{cases} $$ The general solution is usually that the MLE of theta must be a value of $\theta$ for which $\theta \geq x_i$ and which maximizes $1/\theta^n$ among all such values.   The reasoning is that since $1/\theta^n$ is a decreasing function of $\theta$, the estimate will be the smallest possible value of $\theta$ such that $\theta\geq x_i$.  Therefore, the mle of $\theta$, $\hat{\theta}$, is $\max(X_1,\ldots,X_n)$.  Here, I do not understand why we cannot just differentiate the likelihood function with respect to theta and then set it equal to $0$?  Thanks!


How to prevent DDoS attacks on Windows/IIS servers ?

This is a  about DoS and DDoS mitigation.   I found a massive traffic spike on a website that I host today; I am getting thousands of connections a second and I see I'm using all 100Mbps of my available bandwidth.  Nobody can access my site because all the requests time out, and I can't even log into the server because SSH times out too!  This has happened a couple times before, and each time it's lasted a couple hours and gone away on its own.  Occasionally, my website has another distinct but related problem: my server's load average (which is usually around .25) rockets up to 20 or more and nobody can access my site just the same as the other case.  It also goes away after a few hours.  Restarting my server doesn't help; what can I do to make my site accessible again, and what is happening?  Relatedly, I found once that for a day or two, every time I started my service, it got a connection from a particular IP address and then crashed.  As soon as I started it up again, this happened again and it crashed again.  How is that similar, and what can I do about it?


I apparently have multiple versions of a module installed and I am trying to figure out where the files are because only one of them is from package management and I want to delete the other.  Is there a simple way to ask Python where it found a module after importing it?

How do I learn where the source file for a given Python module is installed? Is the method different on Windows than on Linux?  I'm trying to look for the source of the datetime module in particular, but I'm interested in a more general answer as well.


There are so many resources on how to stop bruteforce attacks on your server, but I can't find any good on bruteforce attacks FROM a shared hosting server. I am getting a lot of reports from many different providers that my servers is attacking theirs. Even after scanning with ClamScan and removing a whole lot of malware. Is there an easy way to see which website(or script) on my server is calling, lets say, "/wp-login.php" on another server?

This is a  about Server Security - Responding to Breach Events (Hacking)   See Also:                  Canonical Version I suspect that one or more of my servers is compromised by a hacker, virus, or other mechanism:   What are my first steps? When I arrive on site should I disconnect the server, preserve "evidence", are there other initial considerations? How do I go about getting services back online? How do I prevent the same thing from happening immediately again? Are there best practices or methodologies for learning from this incident? If I wanted to put a Incident Response Plan together, where would I start? Should this be part of my Disaster Recovery or Business Continuity Planning?   Original Version       2011.01.02 - I'm on my way into work at 9.30 p.m. on a Sunday because our server has been compromised somehow and was resulting in a    attack on our provider. The servers access to the Internet   has been shut down which means over 5-600 of our clients sites are now   down. Now this could be an FTP hack, or some weakness in code   somewhere. I'm not sure till I get there.      How can I track this down quickly? We're in for a whole lot of   litigation if I don't get the server back up ASAP. Any help is   appreciated. We are running Open SUSE 11.0.            2011.01.03 - Thanks to everyone for your help. Luckily I WASN'T the only person responsible for this server, just the nearest. We managed   to resolve this problem, although it may not apply to many others in a   different situation. I'll detail what we did.      We unplugged the server from the net. It was performing (attempting to   perform) a Denial Of Service attack on another server in Indonesia,   and the guilty party was also based there.      We firstly tried to identify where on the server this was coming from,   considering we have over 500 sites on the server, we expected to be   moonlighting for some time. However, with SSH access still, we ran a   command to find all files edited or created in the time the attacks   started. Luckily, the offending file was created over the winter   holidays which meant that not many other files were created on the   server at that time.      We were then able to identify the offending file which was inside the   uploaded images folder within a  website.      After a short cigarette break we concluded that, due to the files   location, it must have been uploaded via a file upload facility that   was inadequetly secured. After some googling, we found that there was   a security vulnerability that allowed files to be uploaded, within the   ZenCart admin panel, for a picture for a record company. (The section   that it never really even used), posting this form just uploaded any   file, it did not check the extension of the file, and didn't even   check to see if the user was logged in.      This meant that any files could be uploaded, including a PHP file for   the attack. We secured the vulnerability with ZenCart on the infected   site, and removed the offending files.      The job was done, and I was home for 2 a.m.            The Moral   - Always apply security patches for ZenCart, or any other CMS system for that matter. As when security updates are released, the whole   world is made aware of the vulnerability.   - Always do backups, and backup your backups.   - Employ or arrange for someone that will be there in times like these. To prevent anyone from relying on a panicy post on Server   Fault.


I want to upgrade my laptop OS from Windows to Linux, for Programming and Gaming Purposes I have a Laptop with Below specs Intel(R) Pentium(R) CPU P6100 @ 2.00GHz 2.00GHz 3GB RAM Which Latest Version of Linux Should I Install?

For a given hardware configuration, how do I find out if Ubuntu will run on it? What considerations should I take into account when choosing an Ubuntu version and  such as:    with a lighter desktop than the usual Gnome and Unity  with the even lighter LXDE desktop   Obviously Ubuntu does not run on some processor architectures. So how do I go about choosing the right version and derivate. How can I find out the minmal system requirements?


sudo date > output.txt bash: output.txt: Permission denied   I want to write log message into file, but the permission denied even I add prefix sudo, But when I tried after making output.txt file and changing permission to 755, It works well.   How can I write log meesage without making file and changing permission?   simply like sudo date > output.txt --chmod 755 ?

this is the first occurrence where su was required for me.  I read an article about changing the value in /sys/devices/virtual/backlight/acpi_video0/brightness to alter my laptop's screen brightness.  I first noticed that when I would $ sudo echo 10 > brightness I would get permission denied.  I switched to root using su and # echo 10 > brightness changed my brightness almost instantly.  The last weird thing to me happened when I tried # echo 20 > brightness (maxbrightness file holds the value 15) and I got a write error  Could someone explain this difference between sudo and su to me? Understanding the write error would be an added bonus. Any help, pointers, and/or links would be much appreciated.


My iPhone screen is completely frozen. I've pressed the power button by itself to turn my phone off but when it cut back on it was still frozen, so I have no way into my phone.

I understand that when I press and release the power button on the top of my iPhone or iPad, it stays on but turns off the screen.  Whereas if I press and hold the power button, a "slide to turn off" control appears on the screen.  Sliding this, as I was told, does turn the unit off, but it does so by suspending the RAM to disk (flash memory, actually.) So, when turning on the iPhone or iPad, it isn't so much rebooting the OS as it is resuming it from flash storage.  How to force the OS to completely reboot on these devices?


When i login i see  8 packages can be updated. 7 updates are security updates.      When i try    apt-get update  Hit:1 http://us.archive.ubuntu.com/ubuntu xenial InRelease Hit:2 http://us.archive.ubuntu.com/ubuntu xenial-updates InRelease       Hit:3 http://us.archive.ubuntu.com/ubuntu xenial-backports InRelease     Get:4 http://security.ubuntu.com/ubuntu xenial-security InRelease [94.5 kB] Fetched 94.5 kB in 0s (161 kB/s)                                Reading package lists... Done      When i try    apt-get upgrade Reading package lists... Done Building dependency tree        Reading state information... Done You might want to run 'apt-get -f install' to correct these. The following packages have unmet dependencies:  linux-image-extra-4.4.0-31-generic : Depends: linux-image-4.4.0-31-generic but it is not installed  linux-image-generic : Depends: linux-image-4.4.0-31-generic but it is not installed Recommends: thermald but it is not installed E: Unmet dependencies. Try using -f.      If i try apt-get -f install as suggested above that also fails   Reading package lists... Done Building dependency tree        Reading state information... Done Correcting dependencies... Done The following packages were automatically installed and are no longer required:   linux-headers-4.4.0-21 linux-headers-4.4.0-21-generic linux-headers-4.4.0-22   linux-headers-4.4.0-22-generic linux-image-4.2.0-34-generic linux-image-4.4.0-21-generic   linux-image-4.4.0-22-generic linux-image-extra-4.2.0-34-generic linux-image-extra-4.4.0-21-generic   linux-image-extra-4.4.0-22-generic Use 'apt autoremove' to remove them. The following additional packages will be installed:   linux-image-4.4.0-31-generic Suggested packages:   fdutils linux-doc-4.4.0 | linux-source-4.4.0 linux-tools The following NEW packages will be installed:   linux-image-4.4.0-31-generic 0 upgraded, 1 newly installed, 0 to remove and 14 not upgraded. 5 not fully installed or removed. Need to get 0 B/18.7 MB of archives. After this operation, 55.5 MB of additional disk space will be used. Do you want to continue? [Y/n] Y (Reading database ... 225185 files and directories currently installed.) Preparing to unpack .../linux-image-4.4.0-31-generic_4.4.0-31.50_amd64.deb ... Done. Unpacking linux-image-4.4.0-31-generic (4.4.0-31.50) ... dpkg: error processing archive /var/cache/apt/archives/linux-image-4.4.0-31-generic_4.4.0-31.50_amd64.deb (--unpack):  cannot copy extracted data for './boot/vmlinuz-4.4.0-31-generic' to '/boot/vmlinuz-4.4.0-31-generic.dpkg-new': failed to write (No space left on device) No apport report written because the error message indicates a disk full error                                                                               dpkg-deb: error: subprocess paste was killed by signal (Broken pipe) Examining /etc/kernel/postrm.d . run-parts: executing /etc/kernel/postrm.d/initramfs-tools 4.4.0-31-generic /boot/vmlinuz-4.4.0-31-generic run-parts: executing /etc/kernel/postrm.d/zz-update-grub 4.4.0-31-generic /boot/vmlinuz-4.4.0-31-generic Errors were encountered while processing:  /var/cache/apt/archives/linux-image-4.4.0-31-generic_4.4.0-31.50_amd64.deb E: Sub-process /usr/bin/dpkg returned an error code (1)   Based on Comments  ----------------- Filesystem                 1K-blocks     Used Available Use% Mounted on  /dev/sda1                     240972   229789         0 100% /boot

My /boot partition is nearly full and I get a warning every time I reboot my system. I already deleted old kernel packages (linux-headers...), actually I did that to install a newer kernel version that came with the automatic updates.  After installing that new version, the partition is nearly full again. So what else can I delete? Are there some other files associated to the old kernel images?  Here is a list of files that are on my /boot partition:  :~$ ls /boot/ abi-2.6.31-21-generic         lost+found abi-2.6.32-25-generic         memtest86+.bin abi-2.6.38-10-generic         memtest86+_multiboot.bin abi-2.6.38-11-generic         System.map-2.6.31-21-generic abi-2.6.38-12-generic         System.map-2.6.32-25-generic abi-2.6.38-8-generic          System.map-2.6.38-10-generic abi-3.0.0-12-generic          System.map-2.6.38-11-generic abi-3.0.0-13-generic          System.map-2.6.38-12-generic abi-3.0.0-14-generic          System.map-2.6.38-8-generic boot                          System.map-3.0.0-12-generic config-2.6.31-21-generic      System.map-3.0.0-13-generic config-2.6.32-25-generic      System.map-3.0.0-14-generic config-2.6.38-10-generic      vmcoreinfo-2.6.31-21-generic config-2.6.38-11-generic      vmcoreinfo-2.6.32-25-generic config-2.6.38-12-generic      vmcoreinfo-2.6.38-10-generic config-2.6.38-8-generic       vmcoreinfo-2.6.38-11-generic config-3.0.0-12-generic       vmcoreinfo-2.6.38-12-generic config-3.0.0-13-generic       vmcoreinfo-2.6.38-8-generic config-3.0.0-14-generic       vmcoreinfo-3.0.0-12-generic extlinux                      vmcoreinfo-3.0.0-13-generic grub                          vmcoreinfo-3.0.0-14-generic initrd.img-2.6.31-21-generic  vmlinuz-2.6.31-21-generic initrd.img-2.6.32-25-generic  vmlinuz-2.6.32-25-generic initrd.img-2.6.38-10-generic  vmlinuz-2.6.38-10-generic initrd.img-2.6.38-11-generic  vmlinuz-2.6.38-11-generic initrd.img-2.6.38-12-generic  vmlinuz-2.6.38-12-generic initrd.img-2.6.38-8-generic   vmlinuz-2.6.38-8-generic initrd.img-3.0.0-12-generic   vmlinuz-3.0.0-12-generic initrd.img-3.0.0-13-generic   vmlinuz-3.0.0-13-generic initrd.img-3.0.0-14-generic   vmlinuz-3.0.0-14-generic   Currently, I'm using the 3.0.0-14-generic kernel.


I try to write a regex for a date pattern (mm/dd/yyyy ; m/d/yy ; etc...) :      ".*([0-9]+/[0-9]+/[0-9]+).*"   However for my usecase, the year can be omitted. In this case, I still want to match mm/dd. I tried to put the last group opional for that purpose:      ".*([0-9]+/[0-9]+(/[0-9]+)?).*"   But it does not work with a full date pattern (R code below):      str = "hello 2/5/2017 123"     gsub(".*([0-9]+/[0-9]+(/[0-9]+)?).*", "\\1", str)   Result:       [1] "5/2017"   Any idea of what I am doing wrong ?

I have this gigantic ugly string: J0000000: Transaction A0001401 started on 8/22/2008 9:49:29 AM J0000010: Project name: E:\foo.pf J0000011: Job name: MBiek Direct Mail Test J0000020: Document 1 - Completed successfully  I'm trying to extract pieces from it using regex. In this case, I want to grab everything after Project Name up to the part where it says J0000011: (the 11 is going to be a different number every time). Here's the regex I've been playing with: Project name:\s+(.*)\s+J[0-9]{7}:  The problem is that it doesn't stop until it hits the J0000020: at the end. How do I make the regex stop at the first occurrence of J[0-9]{7}?


I have installed ubuntu on my windows machine and now i want to install driver for it but i confused which nvidia driver to install. I have Nvidia GeForce 920M 4GB graphics card. Please help.

I just ordered the Nvidia GTX card. I have a dilemma, though. Should I keep using the driver which is available in "additional drivers" in Ubuntu, or should I install the driver from the Nvidia site?  So which driver is the best for me?


when i run tuxcut,i see this message  i try this command and not run tuxcut  user@server:~$ xhost +localhost su - Defaults env_keep=DISPLAY xhost +localhost & xhost +SI:localuser:root & gksudo "lxterminal --command "nano /etc/default/grub""   how i solve this issue?

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


I have created a feature file and then created the selenium base class where i have created a method to read the data from configuration file and then i have given driver details in stepdefiniation class . Then created runner class and executed it .Getting the Null pointer exception in selenium base class . Can you please hep me out on this   //Selenium Base class import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.util.Properties; import org.testng.annotations.Test;  public class SeleniumBaseclass {      Properties prop;  public void Property()     {          try         {             File f= new File("C:\\Users\\watareuman9\\workspace\\Cucumberproject\\src\\test\\resources\\data\\config.property");              FileInputStream fis = new FileInputStream(f);              prop=new Properties();                      prop.load(fis);                 } catch (Exception e) {                      e.printStackTrace();                 }         }            public String getChromepath()         {             return prop.getProperty("ChromePath");         }          public String getAppurl()         {             return prop.getProperty("URL");         }      }   //stepdefination file:      package Stepdfinations;      import org.openqa.selenium.WebDriver;     import org.openqa.selenium.chrome.ChromeDriver;      import cucumber.api.java.en.Given;      public class Accountstepdefinations  {          @Given("^I navigated to the Login page$")         public void i_navigated_to_the_Login_page()          {             SeleniumBaseclass b1=new SeleniumBaseclass();             System.setProperty("webdriver.chrome.driver", b1.getChromepath());             WebDriver driver=new ChromeDriver();             driver.get(b1.getAppurl());          }          //@When("^I click on the New Account link$")         //public void i_click_on_the_New_Account_link() throws Throwable {             // Write code here that turns the phrase above into concrete actions            // throw new PendingException();           //@Then("^I should see the New Account registration page$")         //public void i_should_see_the_New_Account_registration_page() throws Throwable {             // Write code here that turns the phrase above into concrete actions         //    throw new PendingException();         }      //     //}  //Runner clasas:  package Stepdfinations;  import org.junit.runner.RunWith;  import cucumber.api.junit.Cucumber; import cucumber.api.CucumberOptions;  @RunWith(Cucumber.class) @CucumberOptions(features="src/test/resources/features")    public class Runner  {   }    //Error appearing as null exception in the following method:  public String getChromepath()         {             return prop.getProperty("ChromePath");         }

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


I want to buy a TV in the US because here (Colombia) TVs are more expensive.  Will I have any problem with this? Will the airline allow me to send a TV as luggage? Will the airline pay me if they break the TV?

I'm going to northern Cyprus with Turkish airlines and want to take a 40 inch smart TV that I bought here in the UK with me. Can't find out if this is possible or how much it would cost as it weighs 14kg and as it is fragile how it should be packed if going in the hold. This would be in addition to my 23 kg luggage. Reason is TVs in northern Cyprus are very expensive compared to UK


My attempt For $n$ is even $f_n(x)\leq 0 \implies -f_n(x)\geq 0.$ let us define $g_n(x)=f_n(x) , n$ odd and $g_n(x)=-f_n(x) , n$ even. $$\sum_n f_n(x)=\sum_n(-1)^n g_n(x)$$ Also, given that $f_n$ converges to $0$ uniformly. so, $g_n(x)$ from (2) it is clear that $g_n(x) $ is a decreasing function. By, Leibniz test for alternating series. $$\sum_n f_n(x)=\sum_n(-1)^n g_n(x)$$ converges. $x \in [a,b]$ was aribitrary, So, $\sum_n f_n(x)=\sum_n(-1)^n g_n(x)$ converges and we can define $f$ in $[a,b]$ as $f(x)=\sum_n f_n(x)=\sum_n(-1)^n g_n(x).$ We need to prove the uniform convergence of $\sum_n f_n$ to $f.$ How do I prove the uniform convergence? I tried with $\epsilon$ definition. I am not able to proceed.

If the sequence of functions $f_{n}: X \longrightarrow \mathbb{R}$  is such that $f_{1} \geq ... \geq f_{k} \geq ...$ and $f_{n} \longrightarrow 0$ uniformly in $X$. Prove that $\displaystyle \sum(-1)^{n}f_{n}$ uniformly converges in $X$   Since $f_{n}$ is uniformly convergent, the convergence of $f$ not dependes of $x$. Thus, is the proof reduced to the Leibniz test?


Here is my Form:    <title>Stats</title>
Member Information Form
  <form action="submit_mbr_nfo.php" method="post">     Member ID <input type ="text" name= "mbrid"/>
     Member Name <input type="text" name="mbrnm"/>
     Actual Name <input type="text" name="atlnm"/>
     <input type="submit" value="Save"/> </form>      Here is my PHP file:  <?php //Define database properties in global variables define('DB_NAME', 'STATS'); define('DB_USER', 'root'); define('DB_PASSWORD', 'Test'); define('DB_HOST', 'localhost');  //store connection props in var $link = mysql_connect(DB_HOST, DB_USER, DB_PASSWORD);  //check connection if (!$link) {     die ('Could not connect to the Database: ' . mysql_error()); }  //map $_POST to vars $mbr_id = mysql_real_escape_string($link, $_POST['mbrid']); $mbr_nm = mysql_real_escape_string($link, $_POST['mbrnm']); $atl_nm = mysql_real_escape_string($link, $_POST['atlnm']);   $sql = 'INSERT INTO MBR_NFO '.'(MBR_ID,MBR_NM,ATL_NM) '.'VALUES ('$mbr_id', '$mbr_nm','$atl_nm')';  mysql_select_db('STATS'); $exe_query = mysql_query( $sql, $link); ?>   And here is my php error log:  PHP Parse error:  syntax error, unexpected '$mbr_id' (T_VARIABLE) in /Applications/MAMP/htdocs/stats/submit_mbr_nfo.php on line 21   I am very new and learning PHP and HTML, i tried several online solutions but nothing has worked so far. I am able to insert into DB if I don't use $_POST, i.e., manually typing in the values in php code, but that's not the goal, the goal is to use Form to populate MySQL DB.  Any help is appreciated, thank you.

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?


I've noticed in  there are a number of different skins when you choose specific usernames.  For example, entering Moon, Earth or Mars shows you as that particular celestial body.  Is there a list of the rest?


I have held the side button, I have held both buttons down. Each for 6 seconds or even to a minute nothing is working. Please help!

I got it into power reserve but can't figure how to resume normal mode. I have tried tapping and pressing the screen and holding both side buttons.


As part of a social science text, in one place I need to write fractions like 1/2, 1/4, 1/3. How can I write these fractions in an elegant way without using mathematical packages?

I know I've seen somewhere how to typeset 1/2 as ½, but with arbitrary fractions (that is, a macro that takes two arguments and makes the first denominator and the second numerator...). Now I can't seem to find it.  How do I typeset an arbitrary fraction the same way as ½?


I often use  on Mac OSX 10.9 to edit and display documents.  Occasionally, I want to use the live preview option with bibliography content.  The program allows you to enable a run of bibtex, makeindex, or makeglossaries, followed by 1, 2 or 3 extra runs of latex at the end.  This process is great, so long as you are using bibtex for the backend of the bibliography.  Is there any good way to get LaTeXian to run biber instead of bibtex?  I'm happy to entertain command-line hacks as well any more clean methods.

The Mac editor Latexian has built in methods for compiling using latex+dvips, pdflatex and xelatex.  Furthermore, it assumes bibtex and makeindex to deal with bibliographies and indexes, respectively.  How do I customize Latexian to use, e.g. LuaTeX for compiling or Biber for bibliographies?


I am learning various control techniques for 3-Phase ACIMs. So far I have understood about the SPWM implementation.. in which we save Sin values in a LUT and then modulate the duty-cycle of PWM wave using scaled values from the Sin LUT.  But regarding the SVPWM so I could not understand what are its implementation steps? Does it also require a Sin LUT or not?  And if I am implementing a scalar V/F control loop for the 3-Phase ACIM then is it possible to use SVPWM technique to drive the motor?

While learning 3-Phase scalar control of ACIM using STM32F407 MCU I could not clearly understand the diffrence between the following terms: 1. SPWM 2. 6-step PWM 3. SVMPWM  How do they differ from each other? Do we get the same 3-phase sinusoidals from each of the above PWMs and they are 3 different ways to implement it OR Do they differ in the output that we get from them also? Someone told me that SPWM is used to generate Phase-voltages while the other 2 techniques are used to generate Line-voltages. Is this the only difference between them?


I have a powershell script which deletes old backups from NAS storage. I have already tested it using Windows Powershell and it works but I couldn't perform the same thing in SQL Server. I have created a cmdExec type job and then wrote the script below (script is on desktop):  "C:\Windows\system32\WindowsPowerShell\v1.0\powershell.exe"  "C:\Users\domainAccount\Desktop\"  ".\deleteold.ps1 -FolderPath \\192.168.x.x\Backups -FileAge 2 -ListOnly -LogFile \\192.168.x.x\Backups\log.log"   But I do not get any result as when I run the job it just keeps running infinitely until I stop that job.

I have a powershell script that I am trying to add in to a sql agent job, but the job step is failing with the following error      A job step received an error at line 1 in a PowerShell script. The corresponding line is 'import-module SQLPS  -DisableNameChecking'. Correct the script and reschedule the job. The error information returned by PowerShell is: 'Could not load file or assembly 'file:///C:\Program Files (x86)\Microsoft SQL Server\130\Tools\PowerShell\Modules\SQLPS\Microsoft.SqlServer.Management.PSSnapins.dll' or one of its dependencies. This assembly is built by a runtime newer than the currently loaded runtime and cannot be loaded.   I assumed that the error was being caused by differences in the module path, so I explicitly set the path via $env:PSModulePath to match the path of my powershell session where the code runs fine.  I am pretty new to powershell, so any help you could provide would be appreciated  I am just doing some testing right now, so everything is running locally on my desktop.  I am running SQL Server 2012.


let us suppose that we have a number x and we need to find the smallest number larger than x who sum of digits are y. As an example lets take 3 as x and we need to find a number larger than x for which sum of digits is 2 and the answer is 11 . what should be the strategy ? I GOT this while solving a problem  .can i get an example of how to solve this ?                                                                                iterate through the digits of y from right to left, trying to                  increase the current digit and somehow change the digits to the right in order to reach the sum of digits equal to x. Note that if we are considering the (k + 1)-th digit from the right and increase it, we can make the sum of k least significant digits to be any number between 0 and 9k. When we find such position, that increasing a digit in it and changing the least significant digits gives us a number with sum of digits x, we stop the process and obtain the answer. Note that if k least significant digits should have sum m (where 0 ≤ m ≤ 9k), we should obtain the answer greedily, going from the right to the left and putting to the position the largest digit we can.

I am trying to find the smallest number if we are given the sum of its digits. Suppose that sum of digits  is 9 then it should be 9 instead of 18,36,63 and similarly if sum of digits is  11 then desired answer is 29 not 92 or any other number bigger than 29.I tried to write sum of all numbers upto 53 and got this but i am not able to come up with a general formula.                         from 1 to 9 it is just 9.FROM 10 to 18 it is 19,29,39,...... and for 19(1+9) it is 199  that is increase by 100. from 19 to 27 it is 199,299,399,499.... and for 28 it is 1999 that is increase by 1000. from 29 to 36 it is 29999,39999,49999,..... for 37 it is 19999 (increse by 10000). for 38 to 45 it is it is 29999,39999,49999,........999999 and for 46 it is 199999 (increased by 100000)


At my university, in the during lectures and in the equation sheet for our exams, the formula for the Heisenberg Uncertainty Principle is stated as $\Delta x \Delta p_x \geq h$, for example in one of my lecture notes, the following example is illustrated using this formula    However I know that in my textbook (University Physics by Young and Freedman) and pretty much universally the Heisenberg Uncertainty Principle is stated as $\Delta x \Delta p_x \geq \frac{\hbar}{2}$. Using this formula, we can see the example above is off by a factor of $4\pi$.  Is the formula, $\Delta x \Delta p_x \geq h$, that my university uses a valid formula? If so is just a weaker version of $\Delta x \Delta p_x \geq \frac{\hbar}{2}$?

Some websites and textbooks refer to $$\Delta x \Delta p \geq \frac{\hbar}{2}$$ as the correct formula for the uncertainty principle whereas other sources use the formula $$\Delta x \Delta p \geq \hbar.$$ Question: Which one is correct and why?  The latter is used in the textbook "Physics II for Dummies" (German edition) for several examples and the author also derives that formula so I assume that this is not a typing error.  This is the mentioned derivation:     $\sin \theta = \frac{\lambda}{\Delta y}$      assuming $\theta$ is small:      $\tan \theta = \frac{\lambda}{\Delta y}$      de Broglie equation:      $\lambda = \frac{h}{p_x}$      $\Rightarrow \tan \theta \approx \frac{h}{p_x \cdot \Delta y}$      but also:      $\tan \theta = \frac{\Delta p_y}{p_x}$      equalize $\tan \theta$:      $\frac{h}{p_x \cdot \Delta y} \approx \frac{\Delta p_y}{p_x}$      $\Rightarrow \frac{h}{\Delta y} \approx \Delta p_y \Rightarrow \Delta p_y \Delta y \approx h$      $\Rightarrow \Delta p_y \Delta y \geq \frac{h}{2 \pi}$      $\Rightarrow \Delta p \Delta x \geq \frac{h}{2 \pi}$   So: Which one is correct and why?