I would like to use beamer class as backbone for my presentation. However, I encountered a problem. My wish is to put pictures on it and for LaTeX to decide their placement and divide them on frames (Not necessarily one picture per frame).   Only text that should be visible is section and subsection headers describing what is the content of pictures. Is there an easy and elegant way to do it without needing to specify pictures frame by frame.    For example I put a collection of pictures somewhere and automatically they are divided across frames with common header without manual parsing each frame.

I would like a simple script to "scrape" every image in a directory into a single beamer presentation as follows:  $ ls   %img1.jpg  %img2.jpg  %img3.jpg   $ *run script*   %OUTPUT SOMETHING LIKE THIS:  \documentclass{beamer}  % for themes, etc. \mode<presentation> { \usetheme{boxes} }  \usepackage{times}  % fonts are up to you \usepackage{graphicx}  \section{Images in this Directory}  \begin{frame} \frametitle{img1.jpg} \begin{center}         \includegraphics[width=4in]{img1.jpg} \end{center} \end{frame}  \begin{frame} \frametitle{img2.jpg} \begin{center}         \includegraphics[width=4in]{img2.jpg} \end{center} \end{frame}   \begin{frame} \frametitle{img3.jpg} \begin{center}         \includegraphics[width=4in]{img3.jpg} \end{center} \end{frame}  \end{document}


I'm new to bash scripting. I want to call a function from my script which will ssh into a remote computer (on my LAN) and run a command.  So far I have:   function run_ssh_command {     target_ip=$1     username=$2     password=$3     cmd=$4      ssh -l ${username} ${target_ip} ${password} }   I invoke the function from the terminal as follows:  (Note: I give script_name, username and password "real" values when executing the function on my machine. 'ifconfig' is the command I want to run on the remote machine.)  source script_name.sh; run_ssh_command 192.168.X.Y username password ifconfig   Result: Running the above command will get me to the password prompt part of the login process (e.g. same as ssh username@192.168.X.Y)   Question: I want to handle the password entry automatically using the script. What is the "best" way to go about this, in general?

I tried writing a shell script which can do automatic login into a ssh server using password which is mentioned in the script. I have written the following code:  set timeout 30 /usr/bin/ssh -p 8484 root@172.31.72.103 expect  {    "root@172.31.72.103's password"     {       send "password\r"     } }   This code is not running properly, still it is asking for the password. Can somebody please help me in solving this


I'm triyng to do a quick Haskell-like aggregation in Linq (C#), to turn a List into a string in the format "i^j^k..." etc.  is this possible in one query, or should I just do it the old-fasioned  foreach (int i in list) {      string+= i + "^" }   (p.s. yes, that's pseudocode and wouldn't compile.)

I have the following string array:  var sa = new string[] {"yabba","dabba","doo"};   I can convert it to "yabba, dabba, doo" it using string.Join() but what is the super-cool LINQ way of doing it?  The Join extension method seems promising but for a novice like me very confusing.


My question is clear in the title . Why is the heat capacity at constant pressure different from that at constant volume for the same substance?

For an ideal gas, why is the specific heat capacity at constant volume lower than the specific heat capacity at constant pressure?


I have this issue where windows randomly adds keyboard layouts for me. This is beyond annoyance and I'm starting to feel suicidal. (Okay maybe it's not that bad but it's still pretty annoying.)    I want to have two keyboards:   ENG (United States)  CS (Czech QWERTY)   The other two were automatically added by windows (ENG CSQ and ENG UK) but they don't show up in my language list.    The only way to remove them, is to add them manually in the language list, exactly as they are in the keyboard layouts window. Then delete them. I did this several times but the two random keyboards keep coming back. How do I stop windows from adding these automatically?

I have 2 languages installed on my computer, both with a single input method.  I have 2 keyboards: CES-CSQ and ENG-US.    However lately (maybe after the last Win10 update) I started to see 2 additional keyboards in my systray  - namely CES-CS and ENG-CSQ.    Is there there a way to remove those 2 input options (CES-CS, ENG-CSQ) which I do not see in the Control panel's Language options?  Solution described at  question does not apply to my problem because I do not see input options that I want remove in Control panel's Language options.


I need to get more exposure to my business, Is it safe to post some of my articles on my blog, then publish it on Linkedin and Medium? Would I be penalized for duplucate content? or is is just a myth?

I've heard that Google punishes sites with duplicate content.   If I write an article on my blog then import it on Medium (basically a copy/paste) will Google regard it as a duplicate?   Medium.com is a blog platform (sort of).


This is the code:  \documentclass[sttt]{svjour}  \usepackage{graphics}  \begin{document} % \title{Title}  \author{Author} % % \institute{Institute} % \date{Received: date / Revised version: date}  \maketitle % \begin{abstract} Like NSSTs, functional NSSTs also allow non-deterministic transitions, but produce the same  output string for every successful run on a given input. Like NSSTs, aaaa aa functional NSSTs also allow non-deterministic transitions, but produce the same  output string for every successful run on a given input.  \end{abstract} % \section{Introduction} \label{intro} Your text comes here. Separate text sections with \section{Section title} \label{sec:1}  \subsection{Subsection title} \label{sec:2}  \end{document}   This is the output:    The text flowing out of the column due to hyphen. What is the solution to this?

Assume I have a word like Baden-Württemberg. TeX can't hyphenate any of these two word parts. Why?    why isn't it something like this:    where the small ticks indicate possible hyphenation points. A technical (TeXnical) explanation is welcome.   BTW: I am not asking how to circumvent this (by using the babel shorthand "= for example).


Following up the thread here:   and the answer provided by Andrew Cashner, my question now is: I decided to remove the \section stuff and adding the enumerate environment. The problem is that when writing in first item, the columns try to balance each other. How can I make when using \newpage it jumps to write in second column?

I want to display my article's abstract and table of contents side-by-side, to save space. I'm using the multicol package, but it tries to keep each column the same height, and I can't figure out how to force it to move content into the second column.  Here's a mockup; I'm just padding out the abstract to show what it should look like. The layout is perfect, I just want a way to do this properly:  \usepackage{multicol} \begin{document} \maketitle  \begin{multicols}{2} \section*{Abstract}  \lipsum[1-2]  a % padding to make the first column run to   % end of page a  a  a  a  a  a  a  a  a  a  a  a  \tableofcontents \end{multicols}   And here's what it looks like, rendered (perfect except for the padding lines):


In the second volume of Feller's "An Introduction to Probability Theory and Its Applications", section VII.6 on Inversion formulas for Laplace transform starts with the limit  $\displaystyle{\lim_{\lambda\to\infty}e^{-\lambda\theta}\sum_{k\leq\lambda x}\frac{(\lambda\theta)^k}{k!}}$ or, in another form,  $\displaystyle{\lim_{n\to\infty}e^{-n}\sum_{k=0}^{an}\frac{n^k}{k!}}$.  Feller says that the above limit is $0$ if $a<1$ and $1$ if $a>1$, and refers to previous chapters.  I am interested in direct computation of the limit (related question  does not seen illuminating in this aspect), without references to Central Limit theorem (like seen in other similar questions; usage of Poisson variables is possible).

I'm supposed to calculate: $$\lim_{n\to\infty} e^{-n} \sum_{k=0}^{n} \frac{n^k}{k!}$$ By using WolframAlpha, I might guess that the limit is $\frac{1}{2}$, which is a pretty interesting and nice result. I wonder in which ways we may approach it.


I have layers with different elements in each layer. Each elemnt have their own margin from edge.  Is it possible to export file to png\jpg\etc with overlayed layer with dimensions of each separate element (maybe text sizes too)?  I mean smth like that:

Is it possible to produce such design hints (on elements padding, spacing, width, height) automatically in photoshop? Is there any plugin that can potentially do this?


Let $f \colon U \to \mathbb R^n$ ($U \subset \mathbb R^n$ open) be of class $C^1$ and injective. Apparently there is an easy proof to show that $f(U)$ is open. In general it follows from the Invariance of domain theorem.  Does someone know that proof?

Invariance of domain at least in statement seems a simple result. I mean, the first time I saw the statement I thought: "the proof can't be that bad", but when I searched for it I saw that it needs even algebraic topology to prove this result.  My doubt is: isn't there any other proof of invariance of domain that don't need to use algebraic topology? Is there some more elementary proof of this result?  Thanks very much in advance!


I want to load .js file before the </body> in footer only if div with particular class name exists on page. I found the div with class name using if condition. But I am not getting how to add script in footer of page with it.  Here is my if condition code  if ($("#world-map-markers")[0]){  } else {     // Do something if class does not exist }   I want to add this in static html page. There is no backend language.  Thanks

How can you reliably and dynamically load a JavaScript file?  This will can be used to implement a module or component that when 'initialized' the component will dynamically load all needed JavaScript library scripts on demand.  The client that uses the component isn't required to load all the library script files (and manually insert <script> tags into their web page) that implement this component - just the 'main' component script file.  How do mainstream JavaScript libraries accomplish this (Prototype, jQuery, etc)?  Do these tools merge multiple JavaScript files into a single redistributable 'build' version of a script file?  Or do they do any dynamic loading of ancillary 'library' scripts?  An addition to this question: is there a way to handle the event after a dynamically included JavaScript file is loaded?  Prototype has document.observe for document-wide events. Example:  document.observe("dom:loaded", function() {   // initially hide all containers for tab content   $$('div.tabcontent').invoke('hide'); });   What are the available events for a script element?


It has been stated in many places that AUROC is an improper scoring rule.But I haven't seen anyone proving it. Does someone have a working example that shows that maximizing AUROC actually moves away probability estimates from actual probabilities.

A proper scoring rule is a rule that is maximized by a 'true' model and it doesn't allow 'hedging' or gaming the system (deliberately reporting different results as is the true belief of the model to improve the score). Brier score is proper, accuracy (proportion classified correctly) is improper and often discouraged. Sometimes I see that AUC is called a semi-proper scoring rule which makes it not completely bogus as accuracy, but less sensitive than proper rules (for example here ).   What does semi-proper scoring rule mean? Is it defined somewhere?


In the graphs below, The only assumption which seems off pretty much clearly is the normal distribution. Although the top left residual plot shows that it is homoscedastic but the top right one has a funnel shaped with difference in standardised residual as 0.2. Can we still say the plot follows homoscedascity?

I had a question about interpreting the graphs generated by plot(lm) in R.  I was wondering if you guys could tell me how to interpret the scale-location and leverage-residual plots?  Any comments would be appreciated.  Assume basic knowledge of statistics, regression and econometrics.


I need help in calculating the goodness of fit for a Poisson model. The online literature on it is quite scarce, so if you have any useful articles and links I would appreciate it very much.  Here is how the table looks like from SPSS. The outcome variable is a count of patents a company has.

I've often seen the advice for checking whether or not a Poisson model fit is over-dispersed involving dividing the residual deviance by the degrees of freedom. The resulting ratio should be "approximately 1".  The question is what range are we talking about for "approximate" - what is a ratio that should set off alarms to go consider alternative model forms?


$$F=G\dfrac{m_1m_2}{r^2}$$  I wanted to know why is $r^2$ there? ($r^2$ means the square of the distance between the $2$ objects)

This question is puzzling me since I learnt about the gravitation law in school. Why did Newton guess/assume that gravitational force is inversely proportional to the square of distance?  Did he verify that experimentally? (I remember hearing that the first experimental verification of the law of gravitation was after Newton's death.)  If the answer to the above question is no, is it for example more plausible to suppose that $F\propto1/r^2$ than to suppose that $F\propto1/r^4$? Did Newton carry out a thought experiment that makes $F\propto1/r^2$ a plausible guess?  So in summary: Why did Newton choose exponent of $-2$ instead of any other exponent? Was it a guess that depended on pure luck or an educated guess?


I would like sub- and subsubsections to be listed in the contents pane of my pdf document, but only the sections are showing up.    Here's an MWE  \documentclass{amsart} \usepackage{lipsum} \usepackage{hyperref} \setcounter{tocdepth}{5} \begin{document} \tableofcontents \section{Section} \lipsum[1] \subsection{Subsection} \lipsum[1] \subsubsection{Subsubsection} \lipsum[1] \end{document}   which produces this:    I can click on the arrow to see the subsections, but I'd like them to show up without having to click.     Thanks for any help!

I am using pdflatex to create a rather long document. The document also has a table of contents, and the PDF naturally has some metadata of this list of contents that I can view in my PDF viewer (here: Apple Preview and Skim on OS X). The list of contents is collapsed by default, but people on the Skim mailing list told me, that this is a setting inside of the PDF. So how can I tell pdflatex to create an expanded list of contents then?


After a long proof that $H^*(\mathbb{R}P^\infty; \mathbb{Z}/2) \cong \mathbb{Z}/2[x]$ with $|x| = 1$, my text claims the following     $H^*(\mathbb{R}P^\infty; \mathbb{Z}) \cong \mathbb{Z}[y]/(2y)$ with $|y| = 2$ because the projection $\mathbb{Z} \to \mathbb{Z}/2$ induces a ring homomorphism, and it is an isomorphism in even degrees. The element $y$ is the preimage of $x \in H^2(\mathbb{R}P^\infty; \mathbb{Z}/2)$ under this morphism.   I understand that we have isomorphisms $H^*(\mathbb{R}P^\infty; \mathbb{Z}) \cong \mathbb{Z}[y]/(2y)$ on the level of cohomology groups, and that $\mathbb{Z} \to \mathbb{Z}/2$ induces a ring epimorphism between coefficients in $\mathbb{Z}$ and $\mathbb{Z}/2$, but I don't see how we can conclude that the isomorphism is a morphism of graded rings as well. Can someone give some extra steps for that?

What is the cohomology ring  $$ H^*(\mathbb{R}P^\infty;\mathbb{Z})?$$ $$ H^*(\mathbb{R}P^n;\mathbb{Z})?$$  for mod 2 coefficient, the answer is on Hatcher's book and . For the graded module structure, it is obtained from the homology struture.


Injected, cooked until 160, wrapped, cooked until 200, just like it says online. Still very rubbery and tough.  Maybe my meat thermometer is inaccurate? Maybe I should go beyond 200 next time.  It was a very small brisket, about 4.5 pounds.

I smoked my first brisket last weekend and even though it wasn't terrible it was a little dryer and rougher than I would have liked.  Here is the smoker I used:   Here are the steps I followed (along with some notes on things I may have done wrong):   I bought a four pound fresh brisket from a butcher.  It was 9.99/lb (next time I'm going to hit up Sam's club and try and get a 10-12 lb packer cut of USDA Choice) I used Stubb's store bought dry rub.  I rubbed it on and then seared the meat on the grill.  I did not sear the fat cap. (Should I have let the dry rub sit longer?  Also, next time I'm thinking about doing equal parts salt, pepper, and paprika.  Should I have seared at all?  A lot of people seem to throw the meat right in the smoker after giving the dry rub some time to set in). I had turned the smoker on and set it to 200 degrees before searing, so when I put the brisket in it was at 200 degrees and was already smoking.  I used dry wood chips and filled the water pan to the mark specified in the pan. The smoker stopped producing smoke about 30 min in.  I wet some wood chips and put them in, but the smoke never came back.  (How often should I be adding wood chips?  Should they be wet? How long should the smoker be spitting out smoke?) I let it sit for six hours.  I didn't have a meat thermometer at the time.  (What internal temp should I go for next time?) I pulled the meat out, didn't wrap it in foil, and cut it after 20 min.  The bark looked nice but the meat was brown like a pot roast. I know when I get good restraunt BBQ that the meat tends to be a little red/pink.  The meat still tasted ok although it was a little tough.   Other questions.  Should I have wrapped the brisket in foil at some point?  When should I do this and what are instructions for after?  Some people seem to advocate doing so once the meat hits ~150 degrees F which will drastically decrease the cooking time.  Others seem to advocate taking the brisket out when it hits about 180, wrapping it in foil, then putting it in an empty cooler until it rises to ~200.  I know that this is really a bunch of questions rolled into one but I feel like this is a typical experience for a smoking newbie like myself.  I don't expect answers for every item but please try and point out the things I've done which are just empirically wrong.


Consider there are two applicants for a job. One of the applicants is a man, and it is known that he was born on a Wednesday. What is the probability that the second applicant is also a man? (I am  sure its not 1/2)

The following probability question appeared in an :     I have two children. One is a boy born on a Tuesday. What is the probability I have two boys?   The claim was that it is not actually a mathematical problem and it is only a language problem.    If one wanted to restate this problem formally the obvious way would be like so:  Definition: Sex is defined as an element of the set $\\{\text{boy},\text{girl}\\}$.  Definition: Birthday is defined as an element of the set $\\{\text{Monday},\text{Tuesday},\text{Wednesday},\text{Thursday},\text{Friday},\text{Saturday},\text{Sunday}\\}$  Definition: A Child is defined to be an ordered pair: (sex $\times$ birthday).  Let $(x,y)$ be a pair of children,  Define an auxiliary predicate $H(s,b) :\\!\\!\iff s = \text{boy} \text{ and } b = \text{Tuesday}$.  Calculate $P(x \text{ is a boy and } y \text{ is a boy}|H(x) \text{ or } H(y))$  I don't see any other sensible way to formalize this question.    To actually solve this problem now requires no thought (infact it is thinking which leads us to guess incorrect answers), we just compute  $$ \begin{align*} & P(x \text{ is a boy and } y \text{ is a boy}|H(x) \text{ or } H(y)) \\\\ =& \frac{P(x\text{ is a boy and }y\text{ is a boy and }(H(x)\text{ or }H(y)))}         {P(H(x)\text{ or }H(y))} \\\\ =& \frac{P((x\text{ is a boy and }y\text{ is a boy and }H(x))\text{ or }(x\text{ is a boy and }y\text{ is a boy and }H(y)))}         {P(H(x)) + P(H(y)) - P(H(x))P(H(y))} \\\\ =& \frac{\begin{align*} &P(x\text{ is a boy and }y\text{ is a boy and }x\text{ born on Tuesday}) \\\\    + &P(x\text{ is a boy and }y\text{ is a boy and }y\text{ born on Tuesday}) \\\\    - &P(x\text{ is a boy and }y\text{ is a boy and }x\text{ born on Tuesday and }y\text{ born on Tuesday}) \\\\    \end{align*}}    {P(H(x)) + P(H(y)) - P(H(x))P(H(y))} \\\\ =& \frac{1/2 \cdot 1/2 \cdot 1/7 + 1/2 \cdot 1/2 \cdot 1/7 - 1/2 \cdot 1/2 \cdot 1/7 \cdot 1/7}         {1/2 \cdot 1/7 + 1/2 \cdot 1/7 - 1/2 \cdot 1/7 \cdot 1/2 \cdot 1/7} \\\\ =& 13/27 \end{align*} $$    Now what I am wondering is, does this refute the claim that this puzzle is just a language problem or add to it? Was there a lot of room for misinterpreting the questions which I just missed?


Here is how I tried solving this problem:  $\cos{z} = \frac{e^{iz}+e^{-iz}}{2} = -2 \Leftrightarrow e^{iz}+e^{-iz} = -4$  Multiply by $e^{iz}$:  $e^{2iz} + 1 = -4e^{iz} \Leftrightarrow e^{2iz}+4e^{iz} + 1 = 0$  Substitute $e^{iz}$ with $x$ and solve for $x$:  $x^2 - 4x + 1 = 0 \Rightarrow x = 2 \pm\sqrt{3}$  Substitute back and solve for $z$:  $e^{iz} = 2\pm\sqrt{3} \Leftrightarrow iz = 2\pi ni + \log(2\pm\sqrt{3}) \Leftrightarrow z = 2\pi n -i\log(2\pm\sqrt{3})$  Answer: $z = 2\pi n -i\log(2\pm\sqrt{3})$ (for $n\in\mathbb{Z}$)  Now I am unsure about the period, some resources say that it should be $2\pi n$, and some say it should be $2\pi n + \pi$. How do I know? I did this how I have learned to do it, but am I doing it wrong?

I couldn't find any, I tried to write $\cos(z)$ as $\cos(x)\cos(iy)-\sin(x)\sin(iy)$ which then gave me  $\cos(x)\cosh(y) - i\sin(x)\sinh(y) = -2$   $\sin(x)=0$ so that imaginary part become $0$  now we have to find $\cosh(y) = -2$ which is not true for no $y$.  is it right or i made a mistake in my substitutions?


I have two tables and these tables are in one page. I wrote explanations about these. Although there a lot of space, explanations cannot be located below the tables. How can I fix these problems?  \begin{table} [!htp]  \caption{Enerji Eş Değerlikleri} \label{tab:endeg} \begin{center}     \begin{tabular}{lrr}         Tür & Jul & BTU\\         \hline\hline         1 BTU &  $1054 $ J & -\\         1 kWh & $3,6x10^6 $J & $3.412$ BTU\\         1 kalori &  $4,184 $ J & $3,968x10^{-3}$ BTU \\         1 eV & $1,602x10^{-19}$ J & $1,52x10^{-22}$ BTU\\         \hline\         \textbf{Kaynak:} (Crawley, 2013)             \end{tabular} \end{center}

Is there any package or a method to force LaTeX to keep floating environments like table and figure closer to where they are declared?


Is it possible to buy SIM card in Turkey for the time of travel? If so, how much does it cost and how much do calls, texts and - the most important - data transfer cost in average?

Next month I am traveling to country X, where I would need Y minutes of calls, Z text messages and most importantly Q megabytes of data. How can I find the cheapest/most reliable SIM card for my needs?


We know that the mtime of a file can be earlier than the ctime when you make copies of files (or, in my case, move files between file systems without successfully retaining timestamps).  I see many web search results on how to copy the ctime to the mtime (using touch), but not vice versa.  In the below example, I want the file WXBR.m4b to show it as created in 2014, not 2019. Can this be done?  $  stat WXBR.m4b   File: 'WXBR.m4b'   Size: 370988549       Blocks: 724592     IO Block: 4096   regular file Device: 851h/2129d      Inode: 13          Links: 1 Access: (0755/-rwxr-xr-x)  Uid: ( 1000/sarnobat)   Gid: ( 1000/sarnobat) Access: 2019-08-07 20:40:00.300216369 -0700 Modify: 2015-07-05 19:07:38.752375000 -0700 Change: 2019-08-08 15:37:05.511788978 -0700  Birth: -


I have created env.sh file the contents of which are below  #!/bin/sh  export M2_HOME=/vagrant/tools/maven export PATH=$PATH:$M2_HOME/bin export JAVA_HOME=/usr/lib/jvm/jdk1.7.0_65 export ANT_HOME=/usr/local/apache-ant-1.9.7 export MAVEN_HOME=$M2_HOME   but executing this sh file does not result in env variables being exported. Have to manually execute each line to get them exported. Please help

There are several ways to execute a script. The ones I know are: /path/to/script # using the path (absolute or relative) . script        # using the . (dot) source script   # using the `source` command  Are there any other way? What are the differences between them? Are there situations that I must use one and not another?


I'm a Noob. I was working through a tutorial when I hit some keys causing the problem below (I was creating faces between vertices... holding shift & right clicking the vertices to select, then clicking F to create the faces)  Before I was able to zoom (scroll) toward the object to see the the mesh in finer detail without going through the mesh. Now I just zoom straight through the mesh. So I start to see the mesh in more detail as I zoom, then with 1 more turn of the mouse scroll wheel, I zoom straight through my mesh. It appears to be zooming by the same increments.  Anyone know what I have done & how to sort this?  Image 1: What is see before scrolling my mouse forward.  [![enter image description here][2]][2]  Image 2: What I see after scrolling my mouse forward (It goes through the object). See my clipping values to the right.  [![enter image description here][3]][3]  Iv'e also just noticed that my background image has disappeared (I only mention this as I assume this is caused by the same problem). 'Background Images' is ticked in the properties region! (I can't show this image as apparently I can't show more than 2 links since my 'reputation' is below 10)  Edit: I just solved my problem & feel like a complete idiot! I was in perspective view, I just pushed '5' on the number pad to change to orthographic view & it solved both my problems above :)

I'm having an odd issue - When I try to zoom in on a detail using my MMB, the "camera" in the 3D view seems to be cutting off the exterior surface of my object and showing me the inside instead. I'd expect this behavior, but only when I was much more zoomed in.  If I zoom out a bit (one click on the scroll wheel) then I can see the exterior as I intend.  Is there any way to adjust this behavior?  Thanks!


I have three equations in an align environment which I'd like to be numbered as follows: (1a), (1b), (2) [The numbers are just indicative; I don't want them to be exactly 1 and 2]  With subequations I can easily get the numbering (1a), (1b), (1c)  \documentclass{article} \usepackage{amsmath}  \begin{document} % \begin{subequations}     \begin{align}         \mathbf{a} &= \begin{bmatrix}                     a_1\\                     \vdots \\                     a_2                 \end{bmatrix} \label{eq:1a} \\                 &= \left[ a_1 \ \ldots \ a_2 \right]^\mathrm{T} \label{eq:1b}\\         %         \mathbf{b} &= \left[ b_1 \ldots \b_2 \right]^\mathrm{T}, \label{eq:2}     \end{align} \end{subequations} %   \end{document}   Using some code found , I can increase by one the third equation number, obtaining (1a), (1b), (2a), but that's still not what I want  \documentclass{article} \usepackage{amsmath}  \renewenvironment{subequations}[1][]{%              optional argument: label-name for (first) parent equation   \refstepcounter{equation}% %  \def\theparentequation{\arabic{parentequation}}% we patched it already :)   \setcounter{parentequation}{\value{equation}}%    parentequation = equation   \setcounter{equation}{0}%                         (sub)equation  = 0   \def\theequation{\theparentequation\alph{equation}}%   \let\parentlabel\label%                           Evade sanitation performed by amsmath   \ifx\\#1\\\relax\else\label{#1}\fi%               #1 given: \label{#1}, otherwise: nothing   \ignorespaces }{%   \setcounter{equation}{\value{parentequation}}%    equation = subequation   \ignorespacesafterend }  \newcommand*{\nextParentEquation}[1][]{%            optional argument: label-name for (first) parent equation   \refstepcounter{parentequation}%                  parentequation++   \setcounter{equation}{0}%                         equation = 0   \ifx\\#1\\\relax\else\parentlabel{#1}\fi%         #1 given: \label{#1}, otherwise: nothing }  \begin{document} %% \begin{subequations}     \begin{align}         \mathbf{a} &= \begin{bmatrix}                     a_1\\                     \vdots \\                     a_2                 \end{bmatrix} \label{eq:1a} \\                 &= \left[ a_1 \ \ldots \ a_2 \right]^\mathrm{T} \label{eq:1b}\\ \nextParentEquation         %         \mathbf{b} &= \left[ b_1 \ \ldots \ b_2 \right]^\mathrm{T}, \label{eq:2}     \end{align} \end{subequations} %%   \end{document}   Does anyone know how to modify the code to obtain exactly (1a), (1b), (2)?

I'm trying to make a block of equations where the first two are standalone equations, and the second two are subequations, ie  X=XXXX (1)  X=XXXX (2)  X=XXXX (3a)  =XXXX (3b)  I'm using the amsmath package, with align and subequation, but I can't figure out how to do this without making a separate block for Eqs 1-2 and one for Eqs 3a-3b. That solution is unsatisfactory, because then there is a big vertical gap between the two blocks, and I want them to appear all as one.  Here's the code I have so far, in case it's unclear.  \begin{align} T(x) &= \frac{m}{2{k_{B}}} \left\langle \mathbf{\tilde{v}}{(\mathbf{x}_{i},t)}^{2} \right\rangle\\  \mathbf{u}(x) &= \left\langle \mathbf{v}_{i}(\mathbf{x}_{i},t) \right\rangle \end{align} \begin{subequations}  \begin{align} P_{xy}(x) &= \frac{1}{A} \left\langle \sum\limits_{i} {m \tilde{v}_{i,x} \tilde{v}_{i,y}} + \frac{1}{2} \sum\limits_{i} {\sum\limits_{j\ne i} {r_{ij,y} F_{ij,x}}} \right\rangle \\ \begin{split}  &=\frac{m}{A} \Bigg\langle \sum\limits_{i}{{{{\tilde{v}}}_{i,x}}{{{\tilde{v}}}_{i,y}}} + \frac{a^3\omega _{pd}^2}{4} \\  &\quad \times \sum\limits_{i}{\sum\limits_{j\ne i}{r_{ij,y}{\left\{ \frac{e^{(-{{r}_{ij}}/\lambda )}}{{{r}_{ij}}}\left( \frac{1}{r_{ij}}+\frac{1}{\lambda} \right) \right\}_{x}}}} \Bigg\rangle \end{split} \end{align} \end{subequations}   Any suggestions would be greatly appreciated!


I am looking for to 'grey out' my image entirely - the main purpose is to be able to have high detailed picture and still allow me to read clearly written contents at the top of the image. The grey out filter/effect I am looking for looks like some web or app components background when a pop-up comes out. I am attaching an image showing you an example. I am a Photoshop user but can use something else if necessary. I have tried many filters but none has this disabled/grey mask effect.

I would like to use the overlay effect used on the screenshot(s) below.    I've tried experimenting with several Blending modes but keep missing the mark. I'm sure this has a very easy answer but I'm having trouble recreating the effect on my own.  Here are a few more images for further context:        Thanks in advance for your help.


So I decided that this year I would go all out and learn a bunch which I have been interested in for a long time but never fully tried to get into and am trying to take on discrete math, abstract algebra, graph theory, and number theory but don't know if there is anything I should learn before diving into all these topics. I currently am in 10th grade and have only learned up to precalculus. I prefer books but anything works.

I am going to study computer science next year. I am afraid I can't handle the mathematics in the university because I only know some basic mathematics, such as set theory, simple probability, simple matrix operation and I don't know calculus.   Which books you will recommended maths book for study in computer science? I have found two books by Gilbert Strang,  and . Are they worth to buy ?


I have created a page in wordpress which is hosted in localhost. The page containing two drop down lists. one is for selecting category lists from a table called 'category' and the second drop down list is depended on first, that is for selecting the subcategory from the 'subcategory' table. The category id is added to each subcategory value. The value of subcategory drop down list is depend on the category drop down and i tried to implement this using ajax.   Code of my php file named test_ajax.php             jQuery(document).ready( function(){        jQuery('#category').on('change',function (e){            e.preventDefault();           console.log("start1");           var catId = document.getElementById('category').value;           console.log(catId);           jQuery.ajax({               type: 'POST',             url: "/mudratcr/wp-admin/admin-ajax.php",             data: {'key':catId},             cache: false,             success : function (data) {                      jQuery('#sub_cat').html(data);                          console.log(data);                     }           });       });   });   </script> <form  method="post" name="myform" id="myform">

     &nbsp;	     &nbsp;	     &nbsp;

     Category	     <select name="category" id="category" >           <option value="">Select the category</option>            <?php                 global $wpdb;                 $result_fromDB = $wpdb->get_results("SELECT * FROM `category`");                 foreach ($result_fromDB as $cat) {                        echo "<option value='".$cat->id."' selected>".$cat->name."</option>";                 }            ?>         </select>

     Sub Category	     &nbsp;
<select name="sub_cat" id="sub_cat">         <option value=""> Select Sub category</option>     </select>

 </form>   functions.php-- not written the complete code.  function registerFormAction(){          // To handle the form data we will have to register ajax action.          $catid = $_REQUEST['catId']; //catId is the value of category drop down list      }add_action('wp_ajax_nopriv_submitAjaxForm','registerFormAction');         add_action('wp_ajax_submitAjaxForm','registerFormAction');   When i run this page it shows bad request. Can anyone help me. I am a beginner . And i read many articles about ajax and word press, nothing works

Am try to implement data from database using AJAX based on a drop down list in WordPress. The codes returning 400 bad request in the console. I am hosted the page as localhost.  Here is my theme's functions.php //I changed the Code    function my_enqueue_scripts() {    wp_enqueue_script('jquery'); } add_action('wp_enqueue_scripts', 'my_enqueue_scripts');  function fetchData(){     global $wpdb;      // this can be improved     $catId = isset($_REQUEST['catId']);     if($catId){         $result_data = $wpdb->get_results("SELECT * FROM  sub_category where categor_id = '".$catId."'");         foreach ($result_data as $data) {             echo "<option value='".$data->id."'>'".$data->sub_category_name."'</option>";         }      }     die(); }  // add your ajax action to authenticated users only add_action('wp_ajax_fetch_data','fetchData');   Am also adding the jQuery part here:   <form  method="post" name="myform" id="myform">

     &nbsp;	     &nbsp;	     &nbsp;

     Category	     <select name="category" id="category" >           <option value="">Select the category</option>            <?php                 global $wpdb;                 $result_fromDB = $wpdb->get_results("SELECT * FROM `category`");                 foreach ($result_fromDB as $cat) {                        echo "<option value='".$cat->id."' selected>".$cat->name."</option>";                 }            ?>         </select>

     Sub Category	     &nbsp;
<select name="sub_cat" id="sub_cat">         <option value=""> Select Sub category</option>       </select>

  </form>   Remembering that I am using internal scripts, Please give a solution.


Can you help me to prove, that the cardinality of a finite $\sigma$-algebra is $2^n$ for a $n\in\mathbb{N}$.  My first idea was to look at an easy example, but even there i have a problem. I look at two subsets $A,B\subset\Omega$ and want these to be in the $\sigma$-Algebra. I get $\{\Omega, \varnothing, A, B, A^C, B^C, A\cup B, (A\cup B)^C, A\cup B^C, (A\cup B^C)^C, A^C\cup B, (A^C\cup B)^C, A^C\cup B^C, (A^C\cup B^C)^C\}$. So here at least two elements are missing or there are two elements too much. Can you please tell me where my mistake is and give me a hint how to prove the statement.

I have been asked to prove that the number of elements in a finite sigma algebra over a set $X$ is $2^n$ for some integer $n$. How do I go about this problem? I have no idea where to start. Thanks in advance for any ideas.   Do I need to prove that given a set $F$, $\sigma(F)$ is actually a power set of some set say $S$?


I know this isn't the right place for asking this question, but in other places the answers are so awfull.. I'm studying eletricity, so, I start seeing things like "charges", "electrons has negative charges",etc. But I didn't quite understand what charge is. I search a little bit on the internet and found it related to electromagnetic fields, then I thought "negative and positive may be associeted with the behaviour of the particle in the field, great!", but the articles about e.m. fields already presuppose "negative" and "positive" charges. In other places, I see answers relating charges to the amount of electrons/protons in an atom, but if that's right, the "negative" electron is an atom without any protons? What about the neutron? So, my questions are (1) What are charges; and (2) How a particle can "be" electrically charged. What does that really mean? Thanks for your time.

Is charge of something for (e.g.) an electron related to electromagnetic space if it exists due to energy, due to which it may have mass? I don't know about quantum mechanics or advanced particle models. Can anyone just simply give an intuitive idea?   EDIT I want to mean what actually gives electron charge if it is not assumed fundamental but result of some other physical phenomenon or it is  just the quantity defined to explain physical interactions?I think now it is clear


We changed the sites UI, CMS, link structure. Also Bought a new and better domain name. After we completed everything. We did below step by step;   Created a new web application for old.com/page1.html to new.com/page1.html 301 redirection. Used webmmaster tools for 301 redirection. Sent new sitemaps a long with robots.txt   Although we've got a custom title,meta descrpition and meta keywords for every page, Google takes a piece of sentece from content and uses it for MetaDescription. This is a big problem for our potential clicks on SERP. What should we do for getting back MetaDescription?  The old site is : indirimkodlari.gen.tr  The new site : indirimkodu.gen.tr  Google still shows the old url and right meta description with it.    The new domain name with randomly scraped on Google search of site.com/url    Solution Looking at Google's search cache by using "view source" shows we used the wrong field from database for MetaDescription! Changed it, fixed, and solved!.

I have an issue with my website: Google isn’t using my meta description, instead it’s using the content of the web page and I’m really confused.  Reason I’m confused is because I have checked and I don’t have duplicate page titles, description nor keywords, neither do I have any robots.txt for my website. My page title, description and keyword is unique, and page description is about 150 characters.  I have my site in Google Webmaster Tools and I checked for errors, but found none.  So I really don’t know why Google Search isn’t using my meta description.


I want to clip a shapefile in QGis (las palmas) but I get an error:  global name 'features' is not defined See log for more details; what do I do wrong?

I want to clip a vector polygon with a boundary vector polygon but the process is failing. I am getting the error, "global name 'features' is not defined See log for more details". I don't know what is causing this error.


I am writing a small login form at Java using AWT. Faced a problem while checking user input for login: I need, when user inputed "admin" as login and "password" as password, program outputting "Succes!", but anyway I get "Wrong!" message, even if inputed data meet the condition.    So, what should I do so that the program checks the condition correctly?  Code:  import java.awt.*; import java.awt.event.*; import javax.swing.*;  public class Login extends JFrame {     private JButton button = new JButton("Confirm");     private JLabel label1 = new JLabel("Login:");     private JTextField login = new JTextField("", 8);     private JLabel label2 = new JLabel("Password:");     private JTextField pswrd = new JTextField("", 8);      public Login() {         super("Please log in");         this.setBounds(100, 100, 250, 100);         this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);          Container container = this.getContentPane();         container.setLayout(new GridLayout(3,2,2,2));         container.add(label1);         container.add(label2);         container.add(login);         container.add(pswrd);         button.addActionListener(new ButtonEvent());         container.add(button);     }      class ButtonEvent implements ActionListener {         public void actionPerformed(ActionEvent e) {             if (login.getText() == "admin" && pswrd.getText() == "password")             {                 JOptionPane.showMessageDialog(null, "Succes!", "Output", JOptionPane.PLAIN_MESSAGE);             }             else             {                 JOptionPane.showMessageDialog(null, "Wrong!", "Output", JOptionPane.PLAIN_MESSAGE);             }         }     }      public static void main(String[] args) {         Login app = new Login();         app.setVisible(true);     } }

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


I have this piece of html code:  <form id="cambia_stato" method="get" action=""> <input type="text" name="stato" id="frase_stato" value="" onclick="this.value='';" onblur="setMessaggio()" maxlength="255" /> </form>   and I want to check the value of the "stato" field on submit. I tried two ways:  using onsubmit is not triggered by pressing the Enter key:  <!-- nothing happens with the following --> <form id="cambia_stato" method="get" action="" onsubmit="myFunc()">    So I tried checking the input each time a key is pressed, changing the input attributes adding a onkeypressed event:   <!-- nothing happens with the following --> <input type="text" name="stato" id="frase_stato" value="" onclick="this.value='';" onblur="setMessaggio()" maxlength="255" onkeypressed="myFunc()" />   For now, the function myFunc() is defined as follow:  function myFunc () {     alert('test'); }   Am I going wrong somewhere or do I need a submit button?

Well I am trying to submit a form by pressing enter but not displaying a submit button. I don't want to get into JavaScript if possible since I want everything to work on all browsers (the only JS way I know is with events).  Right now the form looks like this:  <form name="loginBox" target="#here" method="post">     <input name="username" type="text" /><br />     <input name="password" type="password" />     <input type="submit" style="height: 0px; width: 0px; border: none; padding: 0px;" hidefocus="true" /> </form>   Which works pretty well. The submit button works when the user presses enter, and the button doesn't show in Firefox, IE, Safari, Opera and Chrome. However, I still don't like the solution since it is hard to know whether it will work on all platforms with all browsers.  Can anyone suggest a better method? Or is this about as good as it gets?


If the electric field on a positive charge is non-zero, then the charge accelerates in the direction of the field.   The field at the surface of a conductor is perpendicular to the surface. Why don't the surface charges accelerate away from the surface of the conductor then?

Say you have a conductor, filled with free electrons. The nuclei have a weak pull on the valence electrons so they are moving around in the conductor.  But the electrons don't leave the solid. If you bring a positively charged object near the conductor, the electrons might move to the other side of the object, but won't leave it, almost as if there's a "wall" blocking it.   Why do surfaces act like barriers/walls for free electrons?  I have gotten the following explanations:  1) They are attracted by the nuclei so they are pulled back.  My problem with this: Conductors have a weak attraction force on the electrons, so why does it take an extremely large force to counteract the pull by the nuclei? And also what makes the boundary so special?  If the electron can move within the solid freely, what makes it so much harder to move outside the solid, since the force by the nuclei is the same?  2) Think of the electrons as being held by the nuclei by a string. If you pull on it, you might be able to move the electron away but you would need a stronger force to break the "string" of the nuclei.  My problem with this: This analogy doesn't work. Elastic strings follow Hooke's Law:  $$F = kr$$ where $k$ is a constant and $r$ is the distance. As the distance increases, the force pulling back increases.  Electromagnetic forces however follow Coloumb's Law:  $$F = \frac{kq_1q_2}{r^2}$$  As the distance increases, force pulling back decreases.  I am not looking for a mathematical proof. I am looking for an intuitive explanation. Something like an analogy would help a lot, but any other explanation you feel would be more helpful is welcome.  Also note that I know that you can get electrons to leave a conductor, but this requires a high voltage.  Related:


Given the sentence,     This exception was thrown __ invalid input.    Which preposition should I use to fill in the blank — because of or due to?   Is either generally preferable for specifying cause or reason?

Is it fine to use due to in place of because of ? How about the other way around? Are any of these sentences ungrammatical?   He was lost because of the storm. He was lost due to the storm. He lost his way due to the storm. He  lost his way because of the storm.


Real games that use powerful video cards.

This question exists because it has historical significance, but it is not considered a good, on-topic question for this site, so please do not use it as evidence that you can ask similar questions here. See  for more information.   What games are available that run natively on Ubuntu?  Please limit one game per answer - and include why you enjoy the game.


I can't figure out for the life of me if it should be "should's" or "shoulds."  It's a follow up sentence of saying, "that's a lot of should's."  (there was also question as to whether the period should go inside or outside of the quotation mark after should's)  I looked over the link of Is "’s ” ever correct for pluralization? but still couldn't figure out what the solution would be to my question. Being more direct of whether it should be should's or shoulds would be more helpful, thanks!

A relatively modern dictionary (I don’t know which one, because we’ve cut out the pages and used them as wallpaper in our bathroom, but I know it’s less than 20 years old) indicates that R’s is one correct pluralization of R, as is Rs, but whichever dictionary this is, it’s kind of a no-name brand, so I’m not sure I trust it.  I’ve always wondered what the best way was to pluralize single letters or numerals, like 2’s or 2s.  What’s correct?


Context  I'm using Windows 8.1 on a laptop with broken USB ports. I want to install UBUNTU and remove Windows.   I tried to use Unetbootin but I got error 15 in the installation.  Any help for a newbie?  I'd appreciate it.

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


Lately, I've been seeing some pretty liberal definitions of "exact duplicate" in some people closing SO questions.  If I recall correctly, Jeff had intended to make it so that there were loose rules on closing duplicate questions.  So I had always assumed that an exact duplicate was meant to be... well... an exact duplicate.  So that if someone were to accidentally double-post a question, the second one would be closed.  Extremely similar topics should be posted in the thread itself.  If I wanted to be berated for not utilizing search better, I'd go post on usenet.  Now I realize that people who close threads don't mean to berate people.  But it's difficult not to take offense at having a thread closed as a duplicate, and I feel that this may chase newbies away.  What is your interpretation of "exact duplicate?"

I thought that this question  was a duplicate (sorry, as a noob meta user I can only post one link, please follow my comment on that question), but other folks don't seem to agree.  If two questions are phrased differently, but describe the same underlying problem (and therefore have the same answers) are they not same question?  Thanks, from a puzzled Binary Worrier :(  Related:


How can I show that   $$ \sum_{y=0}^\infty \frac{λ^y}{y!} = e^λ $$?  I only get so far as to show that the series will converge (by ratio test), but not further, I'm not even sure where to start.

I am trying to see where this relationship comes from: $\displaystyle \sum_{n=0}^{\infty}\frac{x^n}{n!} = e^x$ Does anyone have any special knowledge that me and my summer math teacher doesn't know about? He went over generating functions a few days ago and I did not know exactly what he was talking about. In the middle of his lecture he wrote this generating function. He explained that in this case $a_{n} = \frac{1}{n!}$ for $\displaystyle \sum_{n=0}^{\infty} a_{n} x^n$.   Is the relationship a definition or can it be derived using $\displaystyle \sum_{n=0}^{\infty} x^n $?


I am trying to create a system where there are 3 input buttons (PTM) and a dc motor output. The motor needs to be bidirectional. The 3 buttons are: forwards, stop and backwards. once the forwards or backwards button is pressed, the motor keeps running until the stop button is pressed, or if the other button is pressed in which case the motor will turn in the opposite direction. It would need to be a latched system (I don't need to hold down the button) and have some protection against unintended input (for example if I accidentally press 2 or all the buttons at the same time, it should ignore it). I am trying to not use any microcontroller (Arduino) or software on this project. Ideally, something with logic gates, transistors and a motor driver chip (l293d) will be good. Any suggestions on the circuit for this project or where I can start?

Hello I´ve been working in this project for some days, I need to make a circuit with only relays that can make a dc motor start, stop and a reverse. The thing is that when you push the start or the reverse button the motor need to keep running, I can´t keep it pushed.  This is as far as I can get. SW1 turns the engine on, SW5 turns it off and SW7 reverse the motor but only if it is already running. What i need is that the reverse button also turns the engine on. Please help.  notes: -i can only use three push buttons and as many relays as needed. Yes is a school assignment.  THANKS!


Would this app going to work with iPhone as well or if we have any timeline for iPhone app.  I know there are couple out there which are not official apps and they look awful...

We're getting very close to releasing our iOS app on the App Store.  Since the , we have taken on hundreds of users, fixed a lot of bugs, and we have approached feature completion for v1.0.  We're still working on finishing touches and fixing crashes - but there aren't too many of those these days.  We believe we'll have this out in .    Current Alpha Testers:  We want to extend to you a huge thank you for using our app and giving us feedback.  We've made a ton of improvements that filtered through  here on meta.  We're pretty greedy, though, and we want more of your feedback as we get close to beta.  If you've been using the app, please leave an answer to tell us how you think we've done so far.  Don't go easy on us - we want to get this as right as we can before hitting the App Store.  You might even consider telling us how many stars you would give us if we were in the store.  Also, we created a room called  for more casual discussion about the app.  Everyone Else:  The alpha will continue in the interim, and we still .  The invitations are sent out once a week (usually), so if you don't get an invite right away, don't panic.  We'll get to you.  Bugs or feature requests should be reported here on meta and tagged .  Update, 5/1/2014    As of today, the app is submitted for review.  A great big thanks to all our alpha testers!  Your feedback has been invaluable and has truly helped us make the app much better than it would have been without you.  So what now?  Well, we intend to keep the alpha test group around, except now we're considering it the "beta channel".  It's still important to us, particularly since the update cycle through the AppStore is slow.  We'll still roll out updates in the same way that we have been.  We will also from time ask for targeted feedback on specific features.  And, lastly, if you're just now getting here and wished you had signed up for the alpha, feel free to sign up now anyway.  The form is still there, and we may still let in additional users to the beta channel depending on what our "active users" count looks like.


One of the interpretation of special relativity states that the time is an illusion and does not really exist. This interpretation promoted Einstein himself in his condolence letter after the death of his friend Michelle Besso(but let's set aside if he actually meant this emotional letter seriously). This interpretation takes into account the determinism that the theory contains. Relativity, contrary to the quantum mechanics, is purely deterministic.  However, I would like to know if there are actually any reasons why to suppose the "nonexistence" of time. Why to chose time from the four dimensions that relativity describes? The theory does not explicitly state we should choose the time dimension to be non-existent, the same can be told about space. Yes, relativity brought to life the problem with definition of simultaneity in time, but the relativity of simultaneity in space is much more trivial and older than the time one.   Also, if we choose to accept that the universe is deterministic and expanding, then the apparent freedom of movement is just as big of an illusion as the one of our perception of time. Because if the universe is deterministic, you have actually no freedom in movement through space - you are predestined to move as you move. If we choose to accept the expansion of the universe, we can also say that we are continuously moving "forwards" in space, let's say from a point our particles were at the moment of the big bang. And probably the point is even out of our reach now thanks to the rapid expansion in the first few moments after the big bang.  Is it only our experience from other fields, like the said thermodynamics, that dictates to choose the interpretation in which we treat time as being "non-existent"? Or are there actual reasons within the relativity itself that the time should be treated as such? Or the apparent empirical observation(irrelevant if time should be an illusion and contradicted in the quantum field theory in which we can interpret antiparticles as particles moving backwards in time and the problem of not enough backwards-time-travelling elements of our world gets transformed into the baryon asymmetry problem) that everything moves forwards in time?

This is an attempt to gather together the various questions about time that have been asked on this site and provide a single set of hopefully authoritative answers. Specifically we attempt to address issues such as:   What do physicists mean by time? How does time flow? Why is there an arrow of time?


I can identify open connections by   netstat -a  But I wonder if there is a simple way to identify what running exe is making the connection.

My Internet connection has been slow lately, and I think it might be a possible attack. A friend has told me to use , but it is a big install, and I do not have the time to learn how to use it. Is there an easier way to see all the connections on my PC so I can take further action?


I wrote a simple equation like this  \begin{equation}   Compress Ratio = \frac{n-u} {n} \times 100 \end{equation}   However in the output there is no "space" between Compress and Ratio and they are concatenated.  How can I fix that?

Lets say I have something like:   \[ Let x = number of cats \]   (This is a contrived example, but pretend we are actually inside a long align environment block...) "Let" and "number of cats" need to be written like normal text, while x= needs to be math type text.  I've seen this:  \[ \mbox{Let } x = \mbox{ number of cats} \]   and this:  \[ \textrm{Let } x = \textrm{ number of cats} \]   They seem to produce equivalent output, but I'm not sure which is the "correct" one. Also, they are not ideal in that the extra space needs to be placed inside the text mode block, otherwise it is ignored as math mode and butts the text right up against the math.  Ideally there would be some command which allowed embedding text into an equation, which correctly inserted leading and trailing space around the block as required without adding space inside the text block.  How does one do that "correctly"?


I have friends that are no longer active on my Facebook account.  How do I delete them and get them off my friends list?

Every other image I see hotlinked from Imgur returns a "403 - Forbidden" error.  If I copy and paste the link into my browser the image will load. Or if I delete the initial i. in the URL, the image loads.   The image will not load if it's used in a BBCode style tag, or if I right click on it and choose open in a new tab.  Do you know the cause or a fix?  These are a couple of examples that you'll probably be able to see, but I can't unless I do one of those above mentioned actions:


exhausted noob here. I have basically 2 questions...  Sorry for clarification the switches are inside a loop which gets a bunch of numbers and then sorts them using OrderByDescending(). My problem is now I dont know which numbers there are, I only know that they are ordered by descending. Now I have a priority on numbers some specific number is more important for me than other (there is no rule or logic behind that). But on the other hand none of the numbers I am looking for could be inside, so as a "default" return or work with the highest number there was inside the collection.  1: are switch-cases order sensitiv? Assuming I switch on a range of 1 to 5 and for me 4 is of higher priority than the rest would that work as intended?  switch(number) { case 4: DoFancyStuff(); break; case 3: NotTooFancy(); break; case 1: StillOk(); break; case 2: Bad(); break; case 5: SuperBad(); break; default:break; }   Anyway, further lets assume number is ordered by descending. But I do not now know the possible range of number, it could be 2, 4, 8, 16, and so on but a number could be missing: 2, 4, 16, ...  So if I have to say  switch(number) { case 32: Nice(); break; case 64: OkToo(); break; case 128: Nah(); break; case 8: OkStillTakeIt(); break; default: break; }   So as the numbers are ordered by descending order the big ones come first but they do not have the highest priority there could be a number coming with the highest (priority) one (first case) but it also does not have to... and if none fits I want to take the highest one but that is "lost".  How do I fix that? Or am I just overthinking? Wrong approach? My brain is exploding from thinking about it.

When writing a switch statement, there appears to be two limitations on what you can switch on in case statements.  For example (and yes, I know, if you're doing this sort of thing it probably means your  (OO) architecture is iffy - this is just a contrived example!),    Type t = typeof(int);    switch (t) {      case typeof(int):       Console.WriteLine("int!");       break;      case typeof(string):       Console.WriteLine("string!");       break;      default:       Console.WriteLine("unknown!");       break;   }   Here the switch() statement fails with 'A value of an integral type expected' and the case statements fail with 'A constant value is expected'.  Why are these restrictions in place, and what is the underlying justification? I don't see any reason why the switch statement has to succumb to static analysis only, and why the value being switched on has to be integral (that is,  primitive). What is the justification?


I would like to change line-spacing in the editor (and not the document). I use TexMaker, on Windows 7 Enterprise. If this is even possible, do you know what I should do?

Do you know a TeX editor where one can increase the line spacing/change the line spacing in preferences?  LibreOffice Writer could do the trick provided it did not prepend 0xfeff to files encoded in UTF-8, which prevents LaTeX engines from working.  I'm happy with VIm. It's just that I like writing prose in a double-spaced environment.


I would like to give access to my Stack Overflow account to a member of my team.   Is it possible? If yes, how could I protect my profile data?

It has been my understanding that accounts are suppose to be for a specific user. This user, , is a company: . No doubt, this account has provided some quality answers. However, if a specific user cannot be identified, I don't think that the rep gain, rewards, or badges should be given. This should somehow be tagged as a 'Corporate User'. The rep has no real value when you can't be somewhat sure that the same person is giving the answers all the time.  This is where I found an answer by Devart: , peddling a product.    Edit 2 Good points have been brought up and most I can agree with. But we are setting a precedent. Meta Fudgey brought up a good point about the account's ability to use mod tools responsibly and consistently. Maybe this feature is not available to an account that appears to be an umbrella account unless a single user is identified. I think it is important to consider this aspect.    Let me re-iterate: the user(s) has provided excellent content and I would want that to continue. However, there is more at stake here than meaningful content and helpful resources.      Edit The view on 'shared' accounts wasn't so bright a year ago. For most of us, we have information in our profiles that identifies us as individuals. No, I don't have absolute knowledge of the activities on this account and how many people might use it. Meh, for all we know it could be a knowledgeable programmer with some good PR sense. On the other hand, it could be a PR person with no programming knowledge getting the answers from an employee. Who knows...


I accidentally turned of webapp support in the latest version of the Unity Tweak Tool application. Now I get this error when I try to launch it:    How can I turn webapps back on?

com.canonical.unity.webapps   In order to work properly, Unity Tweak Tool recommends you install the necessary packages


When creating serial numbers, one could use only numbers, 0-9.  This causes serial numbers to be quite long.  To save space, one could also user letters A-Z, resulting in shorter numbers, by a factor of 1.56 (log 36 / log 10).  But this can cause trouble reading those serial numbers, since 0 and O are quite similar.  Also l and 1, and mayby I and 1, or even J and 1. So a first approximation seems to be to use the digits 0123456789ABCDEFGHKMNPQRSTUVWXYZ for serial numbers.  That is 32 digits and hence serial numbers are still 1.51 times shorter than in base-10. Is there any well-known best practice for issuing serial numbers?

Is there any kind of guidelines on passcode generation with regards to UX? In particular I just ran into a site that used auto-generated codes but the codes it made were impossible to tell if a letter was a D an O or a 0.  I i l 1 can also be indistinguishable depending on the type style. This would seem like it should be a common UX guideline, never generate codes with those characters. Maybe even U V u v should be removed. g q and 9, 6 and G as well. Next to each other sometimes these are more obvious but in a random code it's not always clear. Do such guidelines exist and are there any other characters that should be avoided? Maybe ! is another one? Note: this question is not about passwords, it's about passcodes (maybe there is another name). A password is something a user can possibly create. A passcode is something a computer creates like emailing you a 6 character code to type in. For example Apple will popup a 6 digit number, a passcode, on an registered Apple device when you try to log into . Apple doesn't have the UX problem above because their passcodes are only digits, no letters.  Conversely some other site had a 10-15 second puzzle to solve, once solved it showed a code  Is that code BB1CA1O8? BB1CA108 ? BB1CA1D8? Get the code wrong and you have to re-fill out the form and solve the 10-15 second puzzle again Note: Obviously if you have 0 and O next to each other you can probably tell them apart. But if you the passcode it shows you is Z35O96 it's not going to be obvious to large percentage of users if that's a letter O or a number zero.


After upgrading to 16.10 I now have a mysterious indicator that I can't get rid of.  Here is a screenshot:    As you can see, there is an indicator with an empty menu next to my network indicator.  It looks to me to be more in KDE style.  I don't think it's any of these:  => ps -ef |grep indicator xxx       2917  2805  0 Oct17 ?        00:04:21 /usr/lib/x86_64-linux-gnu/indicator-application/indicator-application-service xxx       2934  2805  1 Oct17 ?        00:09:42 indicator-multiload xxx       3013  2471  0 Oct17 ?        00:00:00 /usr/lib/x86_64-linux-gnu/indicator-messages/indicator-messages-service xxx       3014  2471  0 Oct17 ?        00:00:00 /usr/lib/x86_64-linux-gnu/indicator-bluetooth/indicator-bluetooth-service xxx       3015  2471  0 Oct17 ?        00:00:00 /usr/lib/x86_64-linux-gnu/indicator-power/indicator-power-service xxx       3019  2471  0 Oct17 ?        00:00:00 /usr/lib/x86_64-linux-gnu/indicator-keyboard/indicator-keyboard-service --use-gtk xxx       3032  2471  0 Oct17 ?        00:00:00 /usr/lib/x86_64-linux-gnu/indicator-sound/indicator-sound-service xxx       3034  2471  0 Oct17 ?        00:00:00 /usr/lib/x86_64-linux-gnu/indicator-printers/indicator-printers-service xxx       3035  2471  0 Oct17 ?        00:00:00 /usr/lib/x86_64-linux-gnu/indicator-session/indicator-session-service xxx       3483  2805  0 Oct17 ?        00:00:00 telepathy-indicator   Does anyone know what this might be, and how to get rid of it?

The following is a systray applet icon that appeared in my Unity session after I upgraded to Ubuntu 16.10. Its menu is tall, narrow and empty. What is it?


I'm pulling a “Dave” and I'm designing my own hashing algorithm.  Not that I intend to use it, I'm not certifiable or anything, I just want the challenge of creating something. I'm not going to get into exactly what I'm doing, because it's probably worthless anyway. I just wanted some advice on how to calculate the chance of collisions.  So, if anybody can enlighten me on how to calculate the probability of collisions happening, I'd greatly appreciate it.

Bad hash functions are not so perfect as in the ""  hypothesis... And a general concept of "collision resistence"  not need the constraint  of independence between the hash function and the sample set.  Let $H$ be a hash function with digest of $k$ bits, and $S$ a input sample set with size $s=|S|$.$H$ is collision resistant if it is "hard to find" two inputs that hash to the same output,   $\exists x\ne y\in S|H(x)=H(y)$  But "hard to find" is not a good definition: to compare the performance of two hash functions $H_1$ and $H_2$ we need a precise metric... Wikipedia  use $Pr[H]$, the ... But, in real-life tests or benchmarking, we have only the number of collisions $c$, and a big standard deviation to compare $c$ values when change $S$ or $H$.  Puting the question in other words:    there are a "standard way" to obtain the real-life $Pr[H]$ of bad hash functions?    Context. Let me be a programmer that buy low quality proprietary software that implement exotic hash functions: the hash function $H$ for me is a , and I need to test it.    So, if the seller of the function says it is resistant, I need to check it by experiments and some statistical analysis of the experimental results.    Back to the question... If this standard exists, I am supposing that is a kind of probability definition, so,  will be someting like (is it? need only to check the number $c$ of collisions) $$Pr[H](S)=\frac{c}{|S|}=\frac{c}{s}$$  Bad hash functions () have characteristic values of $Pr$ that not depends only on $|S|$...  We can use  $c$ to compare the efficiency of the bad hash  with other hashes. I am imagining that  I can  use $c$ or an averaged $\overline{c}$ based on many $c_i$ tests as a metric of collision rates.    NOTES  Let $c_1$ the number of collisions in $H_1(S)$ and  $c_2$ the number of collisions in $H_2(S)$, them we can compare the two hash functions.  To avoid bias we can do an average about many sample sets $S_1$, $S_2$, etc. So there are averaged $\overline{c}_1$ and  $\overline{c}_2$ as good estimators.   we can also estimate the minimum $\overline{c}$ of a hash function with digests of $k$ bits by   $${Pr}_{min}[H](S) ~=~  1 - \frac{2^k!}{(2^k)^s (2^k - s)!} ~\approx~ 1 - exp({-s^2/2^{k + 1}})$$  Conclusion, a good score to compare hash functions is $$q ~=~ Pr[H](S) - Pr_{min}[H](S) ~\approx~ \frac{\overline{c}}{s} -1+exp({-s^2/2^{k + 1}})$$  When $q=0$ we have "perfect hash function", that have an expected behaviour about collisions... Imagining that hashes like SHA1 are always perfect because is impossible to compute $\overline{c}$, but  truncated SHA1 or "bad hashes" can be tested about big $S$ samples. PS: negative $q$ is possible when  $H$ and $S$ are not independent.   My interest is the behaviour of these truncated or bad hashes, and to compare them.


I am using Ubuntu 17.10, I want to make a folder in opt folder/directory and paste something but when I open the opt folder and right click on it the new folder option is unhighlighted and also the paste option I tried to make the folder in opt folder using terminal by mkdir command but it shows Permission denied.  Plz tell me how to do it?

I'm still a little new to Ubuntu and was wondering how I can copy files, in this case Aptana Studio, to /usr/local/ without being denied.   Is there a way to do it in terminal? Or a way to allow myself permission?  I should add that I am using 10.10 Desktop edition, not server.


Studying General Relativity I found, in a demonstration, this vectorial identity :  My question is, what does it mean $(\textbf{A}\cdot \nabla) \textbf{A}$  ? It can't be $\textbf{A}\cdot \nabla \textbf{A}$ because it would be a scalar. Sorry but it's the first time i saw that kind of product. Thanks a lot in advance.

I've seen more than one time the use of the following notation: $(\vec{v}\cdot\vec{\nabla})\vec{v}$ to say $L_v(\vec{v})$ where the matrix $L_v$ is defined as follows: $(L_v)_{ij} := \partial_j v_i$. For example this happens in the usual law of conservation of momentum of an eulerian fluid: $$\rho\Big(\partial_t\vec{v} + (\vec{v}\cdot\vec{\nabla})\vec{v}\Big) = \rho\vec{b} + \vec{\nabla}p$$ My question is: how that notation could "help" us to understand "how things work"? I think this is strange, but physicists are known to have strange notations that in some ways help to understand the nature of things. Take for example the divergence of a vector field $\vec{v}\ $: this is written in some texts as $\vec{\nabla}\cdot\vec{v}$ because if we think at $\vec{\nabla}$ as the vector $(\partial_1, \partial_2, \partial_3)$ then the scalar product $$\vec{\nabla}\cdot\vec{v} = (\partial_1, \partial_2, \partial_3) \cdot (v_1,v_2,v_3) = \sum_{i=1,2,3} \partial_i \ v_i = \text{div}(\vec{v})$$ Now, if I take for example a $2$ dimensional field $\vec{v} = (v_1,v_2)$ we have (correct me if I'm wrong) $$L_v(\vec{v}) =  \begin{pmatrix} \partial_1 v_1 & \partial_2 v_1 \\  \partial_1 v_2 & \partial_2 v_2 \end{pmatrix} \begin{pmatrix} v_1 \\ v_2 \end{pmatrix} = \begin{pmatrix} (\partial_1 v_1)v_1 + (\partial_2 v_1)v_2 \\  (\partial_1 v_2)v_1 + (\partial_2 v_2)v_2 \end{pmatrix} $$ How could I derive "intuitively" the last vector using the notation $(\vec{v}\cdot\vec{\nabla})\vec{v}$?


I recently installed Ubuntu 14.04 on my computer and now I want to change my desktop environment to Gnome 3. I have seen many methods to install Gnome 3 but now I am confused which method should I follow. Please tell me if I can install Gnome 3 with just these commands without any other commands like adding repositories etc.  sudo apt-get install gnome-shell   &  sudo apt-get install ubuntu-gnome-desktop

I followed the instructions for compiling GNOME Shell and it did compile with a few errors here and there but it didn't run. I installed GNOME Shell using sudo apt-get install gnome-shell but I got version 2.31.x, while the latest is 2.91.5 or something. So is there a way for me to install the latest build?   Is there some repository available for the latest build?


I'm a relative newbie working on SP2013 w/o SPD. I have a lookup column for NAMEPD and a text column for NAME NOT FOUND on the same list. NAMEPD is a simple dropdown choice, NAME NOT FOUND is there for the user to input a name in case one is not in the NAMEPD. Is there a calculated column method for displaying the data from either of these columns if data is present?  I have creating a calculated column named NAME1 with the formula =[NAMEPD]&" "&[NAME NOT FOUND] but get the following error:      "One or more column references are not allowed, because the columns   are defined as a data type that is not supported in formulas."   Any help is greatly appreciated.

I have a SP2013 Server but have not been authorized to install SPD2013. I have a list [Web Team Tasker] which has a lookup column containing data from a list on a parent site as well as some subcolumns associated with the lookup column. I would like to on of the subcolumns in a calculated field. Would anyone be able to walk me through the process?


I am looking for a book series that I read between 1988 and 2000, but I can't recall the title or the name. The first book starts with the main character being chosen to learn magic. By the end of the book, he is decent at the rudimentary spells but does not progress any farther as he is banished from the school due to his involvement with killing a teacher. The series goes on with him learning different spells such as shapeshifting, and time travel with each book. There is a particular book that features him fighting off the influences of a statue that he finds with the cover art of the main character overlooking a stormy ocean with the old woman standing in front of him with her back turned. There is a particular scene that I can remember where the main character, now much older, is attempting to gain access to a castle but is blocked by magic wards. To remove the wards, he must strike a bell tower with a bolt of lighting at an exact time. He fails to hit the tower but sees a second bolt of lighting appear from seeming nowhere to hit the tower. He later discovers that this second bolt of lighting was from a version of himself that had learned to travel back in time.

When I was younger (11-12 years old, so the early 2000s) I once read a story where a young boy, who may have been either a young prince or a squire of some sort, is recruited by a wizard and taken to a city to train as a mage.  I seem to remember him living in dorms with the other children at this school, until he gets into difficulty with another of the boys in the dorm. He is kicked out of the dorms and ends up living above a blacksmith shop (I think).  I remember it being the first book in a series of books of which there were about 3 out at the time. I think one of the stories was about the boy going to a tower to do something or other.  Does anyone have any idea what this book series is? I haven't been able to find it for years now but it was a story I really loved.


I'm fairly new to programming, i have to start learning it for Uni.  I have to make a pattern as follow:  5 4 3 2 1 4 3 2 1 3 2 1 2 1 1   I have found ample examples of code for these patterns, just not for mine.  I cannot seem to get the numbers to line up vertically, only underneath each other:  5 4 3 2 1  4 3 2 1     what am i Missing ? I can't seem to find the exact function that other people are using to make their code act like this.    # Question 4. import random  num1 = random.choice([5, 6, 7, 8, 9, 10])  def print_triangle():     for row in range(num1, 0, -1):         for space in range(num1 - row):             print ('')          for col in range(row, 0, -1):             print (col)  print_triangle()

I'd like to do it in Python. What I'd like to do in this example in C: #include <stdio.h>  int main() {     int i;     for (i=0; i<10; i++) printf(".");     return 0; }  Output: ..........  In Python: >>> for i in range(10): print('.') . . . . . . . . . . >>> print('.', '.', '.', '.', '.', '.', '.', '.', '.', '.') . . . . . . . . . .  In Python print will add a \n or space, how can I avoid that? Now, it's just an example, don't tell me I can first build a string then print it. I'd like to know how to "append" strings to stdout.


I recently bought a "travel sized" version of a facial spray that I use so I could bring it on my holiday. But I just looked at the label and saw that it was 118ml, 18ml over the 100ml limit. I just wanted to know if that would still be alright to bring on board.

I know as a fact that I've gotten liquids larger than 3 ounces through the TSA scanner systems (such as sunscreen). I was scolded one time for bringing a shampoo container, but I was still ultimately allowed to bring that container through.  In any case, how often are liquids larger than 3 ounces ultimately confisticated, if I put them in a ziploc bag where they can be clearly seen?


Suppose I have a multiple linear regression model and the errors are not distributed normally.Does the central limit theorem hold true in this case? should i trust the p values of the coefficients of variables assuming the residuals are not skewed?  Will really appreciate any help on this, thank you :)

I've read that "If the error distribution is significantly non-normal, confidence intervals may be too wide or too narrow" (). So, can anyone elaborate on this? When are the confidence intervals narrow and when are they wide? Does it have anything to do with skewness?


I recently graduated with a degree in bachelor of science with a focus interactive and multimedia design. I had to opportunity to take 1 C++ course and 1 HTML course. I was also only required to take one math class, introduction to calculus (and it was hardly calculus, it was more of a math class for designers)  Since graduating I have pursued a career in web development. I'm considering going back for a MS in computer science or MS in web technologies.   I feel my math has suffered dramatically as I have always been behind most others on my math studies (middle school through college). I want to learn calculus as I feel it's an integral part of any CS degree.   Does anyone have any recommendations on any great books that I can read through and teach my self a bit of calculus or other advanced math topics?  Thanks for any advice

Well I have not started calculus yet but I am really keen to. I would love if you suggest some books.  Points to be noted:   I really don't like the way textbooks are written so please no "textbooks"  I am COMPLETELY beginner in calculus. I know a little bit of trigonometry and what functions are but not really in depth.The book should start from the base, I mean really from the base. I may require a precalculus book too if the books don't cover that. I would really love if the book shows how calculus was developed, why it was developed and things like that.   Well,thanks in advance!


Is there a way to suggest that a decision by the "Community" bot could be wrong? I recently made (i.e. suggested) a minor edit to a question, mostly to remove the SHOUTING, which was rejected by Community".   The edit was:   But no reason for the rejection was given. Perhaps it was simply too minor an edit, which I would be happy to accept. But I'm curious.

Why does the Community user sometimes approve or reject edits? How does a machine know if my edit is valid? What does it mean if my edit was rejected by Community?     See also:


It is common to use     1a an historical event      2a an hotel   rather than     1b a historical event      2b a hotel   Why 'an' is used in such case?

A basic grammar rule is to use an instead of a before a vowel sound. Given that historic is not pronounced with a silent h, I use “a historic”. Is this correct? What about heroic? Should be “It was a heroic act” or “It was an heroic act”?  I remember reading somewhere that the h is sometimes silent, in which case it’s an, and when the h is pronounced, it’s a. But then I also remember reading that it depends on which syllable is stressed. And I also think I read somewhere that it might differ between British and American English.  Personally, I pronounce the h, and believe that a is correct. I find that it sounds incorrect to use an and pronounce heroic without the h.  So how do I know when to use a and when to use an with a word beginning with the letter h? Are both acceptable or is there one that is correct?


Why I can't change permission of any files which are located on other partitions like sda2,sda3,sda4 and so on.. When I change it from properties it's immediately change again to it's previous setting.. When I tried with nautilus... it shows

I have a script that I need to execute on an NTFS partition. The script's permission is set to 600.  I attempted to modify the permissions by running chmod 755 script.sh, which doesn't report a failure or anything - but it also doesn't change the permissions on the file:  $ stat script.sh    File: `script.sh'   Size: 297070      Blocks: 584        IO Block: 4096   regular file Device: 811h/2065d  Inode: 35515       Links: 1 Access: (0600/-rw-------)  Uid: ( 1000/  xxxxxx)   Gid: ( 1000/  xxxxxx) Access: 2010-09-30 14:05:16.041621000 -0700 Modify: 2010-09-30 14:05:05.070157000 -0700 Change: 2010-09-30 14:05:05.070475000 -0700  $ chmod 755 script.sh $ stat script.sh    File: `script.sh'   Size: 297070      Blocks: 584        IO Block: 4096   regular file Device: 811h/2065d  Inode: 35515       Links: 1 Access: (0600/-rw-------)  Uid: ( 1000/  xxxxxx)   Gid: ( 1000/  xxxxxx) Access: 2010-09-30 14:05:16.041621000 -0700 Modify: 2010-09-30 14:05:05.070157000 -0700 Change: 2010-09-30 14:05:05.070475000 -0700   As you can see, it remains unchanged.


This is a somewhat minor design issue: Currently, across all SE site chatrooms there is an inline style max-width on the footer logo (bottom right-hand side of each chatroom) that scales the logo if it's width is greater than 150px (there's also a max-height attribute set in the css for limiting the height). This is very noticeable on beta sites with very long names such as "." Certain graduated sites with longer logos, like "," are affected as well.   (actual size) I'd also like to make note that the font color of the main site name portion on the chatroom footer logos don't contrast very well against the dark-blue colored background (with the diagonal scanlines), when compared to the lighter font color of the "beta" text in the logo.  (actual size) Would it be possible to use a better contrasting color for the site name on the beta chatroom footer logo? Would it be possible to change the max-width to something like 250px to improve readability of the logo?

Here, you try:  If it weren't for the text shadow, it might as well be entirely invisible...  The cause is a CSS rule lurking in the transcripts for beta sites only:  #transcript-logo {   background: none repeat scroll 0 0 #273A5D; }   The problem is the #273A5D - a bluish colour not dissimilar to that used for the site name in the beta theme. Disabling that rule yields the much more manageable  I'll admit it is a little hard to read the "beta" in that shot. But if you had to choose which part was readable, wouldn't you choose the bit that tells you the name of the site?  Edit: It happens when actually in a chat room too!


I was reading something in Munkres' book on algebraic topology and at some point I got confused.  He sais that if $B$ is a subgroup of $C$ and if $A$ is free, then the map :  \begin{equation} A \otimes B \to A \otimes C \end{equation} Induced by the inclusion is injective. But isn't this map always injective? Even if $A$ is not free?

Considering  $$0\to \Bbb Z \to \Bbb Z\to \Bbb Z/(2)\to 0$$ We want to show that the tensor product is not left exact by tensoring with $\Bbb Z/(2)$, which apparently gives us what we want.  But I did this, and I get  $$0\to \Bbb Z/(2)\overset{\sim}{\to}\Bbb Z/(2)\overset{0}{\to} \Bbb Z/(2)$$   Where I can't see why this isn't exact? Is there a reason why I can't have the zero map on the right?


I tried to remove wine but it says that virtual packages like wine can't be removed. Also I am unable to find my .wine file.

It turns out that removing a virtual package with apt-get only remove the package itself,  leaving behind the real packages that were installed by it  So how do you remove a virtual package, along with all the real packages that it installs?


I'm trying to replace my AC adapter with a battery. The AC adapter output is 12v @ 500mA DC. I can get a 12v battery, but I can't find one that outputs exactly 500mA. I'm trying to power a strip of LED lights. So I guess the real question is, do I need to reduce the amperage if the battery is the correct forward voltage for the strip? And if so is there a formula to use to reduce the amps? Lets say I get a 12v battery that outputs 7900mA; what type of resistor do i need to get 7900mA down to 500mA without reducing the voltage?  Thanks.

Power supplies are available in a wide range of voltage and current ratings.  If I have a device that has specific voltage and current ratings, how do those relate to the power ratings I need to specify?  What if I don't know the device's specs, but am replacing a previous power supply with particular ratings?  Is it OK to go lower voltage, or should it always be higher?  What about current?  I don't want a 10 A supply to damage my 1 A device.


For the past few days, I've been trying to match my second screen's resolution to my match my main screen.  Using the following code i got from this website, I was to get it done:  xrandr --newmode "1368x768_60.00"   85.25  1368 1440 1576 1784  768 771 781 798 -hsync +vsync xrandr --addmode DVI-I-1 1368x768_60.00 xrandr --output DVI-I-1 --mode  1368x768_60.00   My problem, now, is when i reboot my computer, the second screen goes back to its old resolution. Then, i learned that i have to add these scripts to this file sudo gedit /etc/modules which i did but still didn't work.   I'm new to ubuntu and i'm really liking it. I can get my second screen set.  TIA!

How can I run the following xrandrcommand on startup?  xrandr   cvt 1368 768  xrandr --newmode "1368x768_60.00"   85.25  1368 1440 1576 1784  768 771 781 798 -hsync +vsync xrandr --addmode VGA1 1368x768_60.00 xrandr --output VGA1 --mode 1368x768_60.00


I sing in a choir and most of us are Spanish speakers. We're singing The First Noel, and last night someone questioned whether we should say "the East" pronounced as "thuh East" or "thee East."   The lyrics read:      They looked up and saw a star   shining in the East beyond them far   And to the earth it gave great light   And so it continued both day and night.   I looked up the rule, and it's not clear to me, as I cannot identify whether the 'e' in East is considered a consonant or a vowel sound. Compare 'East' and 'earth'. In the latter, it is clear that the pronunciation should be "thee earth", but the sound of 'e' in 'East' is different, so what should it be?  Also, when I looked up the song sang by other choirs, they say "thee East."   Can you please help and provide the rule that should be followed in this specific case or is it a case of poetic license?

I read that the definite article is pronounced differently depending on the word that follows it.  Which is the exact pronunciation of the?


Prove That $$\sum_{n=1}^{\infty} \dfrac{{H_{n}}^2}{n^2} = \dfrac{17}{360} {\pi}^4$$  I encountered this identity while reading the article about  on Wikipedia. I thought of using the integral representation of Harmonic Number, but the square is creating trouble. Any help will be appreciated. Thanks.

How can I find a closed form for the following sum? $$\sum_{n=1}^{\infty}\left(\frac{H_n}{n}\right)^2$$ ($H_n=\sum_{k=1}^n\frac{1}{k}$).


I am trying to dual boot Windows 7 and Ubuntu 18.04. I just installed Windows 7 64 bit so it is a fresh install. I added a partition for Ubuntu in Windows disk management and then installed Ubuntu 18.04 from a USB using "something else". I used  to install.   I made the partitions in Windows. After booting from USB and creating more partitions in "something else" and clicking on install it gave me an error:     Partition table requires a separate partition for boot loader code.    I installed anyway.   When the install was done it had to restart. But it booted back into Windows, no GRUB. I restarted window and still no GRUB.   So I try to install again and I chose to reinstall over Ubuntu. Same thing. No GRUB.  I am running a  I5-2500 8gb DDR 3 ram gigabyte motherboard 1tb hard drive with Windows 10 unplugged this whole time 500gb hard drive For windows 7 and Ubuntu  Windows 7 says EFI boot mode   I have tried to do (bcdedit /set {bootmgr} path \EFI\ubuntu\grubx64.efi). It says completed successfully. But no diffrance when I restart.

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


I recently organized my modules in /sites/all/modules in 4 differents subfolders: contrib, custom, patches, migration. It works very well, but after using the update manager, the new updated modules appears in /sites/all/modules instead of /sites/all/modules/contrib, so I have to move it manually to contrib. How can I set the default module location to /sites/all/modules/contrib ?  Thanks.

I am able to use Update Manager to install new modules, instead of having to manually upload them. I previously put everything in sites/all/modules, but now have reorganized my modules into sites/all/modules/contrib and sites/all/modules/custom (for the modules I write or modify).  However, Update Manager is still installing new modules in sites/all/modules. Is it possible to tell Update Manager to install new modules in sites/all/modules/contrib instead? I looked for a setting somewhere, but can't find one (D7).


I want to stop the math size from automatically shrinking in math mode. Usually when, for example, having a lot of nested fractions, the size automatically shrinks to make it all fit.  But I want to prevent this. I want it to display in full size even when I have these nested fractions.  How is this possible?

What is best practice for typesetting fractions with large objects in the numerator and denominator?  For example, fractions with limits, integrals, summations, etc... cause the expressions to look contracted and somewhat odd.  I understand that it is probably best to leave this as is when writing mathematics inline, but as a stand-alone fraction I feel it would be much less distracting if the symbols were typeset at normal size and the fraction was given more height in which to place itself.  Are there standards (for pure mathematics) regarding this problem? And what are the options - if it's generally permitted - for expanding the fraction size to incorporate large objects?    Example  \frac{\sum_{i=0}^{n} i^2}{\iint_{D}\frac{\partial (x,y)}{\partial (u,v)}\,\mathrm{d}u\,\mathrm{d}v}   Both the summation and the integral look somewhat cramped.


someObj.java    public class someObj {         private int data;          someObj(int initVal) {             data = initVal;         }         int getAnotherObjectData(someObj bar) {             return bar.data;         }  }     Tester.java      someObj foo = new someObj(30);     someObj bar = new someObj(40);     System.out.println(bar.getAnotherObjectData(foo));     In result, I can get '30'. Why I can access another Object's private variable data?

In Java, are there clear rules on when to use each of access modifiers, namely the default (package private), public, protected and private, while making class and interface and dealing with inheritance?


If the party earns a Dragon Slayer Sword, it can be a type of weapon used by one of the party members but it says it must be a sword, so would a Glaive count?

Are rapiers and scimitars considered swords for magic items like:   Dancing Sword Defender Dragon Slayer Flame Tongue Frost Brand Giant Slayer Holy Avenger Luck Blade Nine Lives Stealer Sword of Life Stealing Sword of Sharpness (scimitar) Sword of Vengeance Sword of Wounding Vorpal Sword (scimitar)   Or are only shortswords (not Sword of Sharpness or Vorpal Sword), longswords and greatswords swords for these items and therefore available?


I am a new programmer, I would like to know how to round to the nearest hundredth. Here is the code import java.util.Scanner;  public class Main {    public static void main(String[] args) {     Scanner in = new Scanner(System.in);      System.out.print("Input first number: ");     double num1 = in.nextDouble();      System.out.print("Input second number: ");     double num2 = in.nextDouble();      System.out.println(num1 + " + " + num2 + " = " + (num1 + num2));      System.out.println(num1 + " - " + num2 + " = " + (num1 - num2));      System.out.println(num1 + " x " + num2 + " = " + (num1 * num2));      System.out.println(num1 + " / " + num2 + " = " + (num1 / num2));   } }  please answer with the code to round to the nearest hundredth. Thank You.

What I would like is a method to convert a double to a string which rounds using the half-up method - i.e. if the decimal to be rounded is 5, it always rounds up to the next number. This is the standard method of rounding most people expect in most situations.  I also would like only significant digits to be displayed - i.e. there should not be any trailing zeroes.  I know one method of doing this is to use the String.format method:  String.format("%.5g%n", 0.912385);   returns:  0.91239   which is great, however it always displays numbers with 5 decimal places even if they are not significant:   String.format("%.5g%n", 0.912300);   returns:  0.91230   Another method is to use the DecimalFormatter:  DecimalFormat df = new DecimalFormat("#.#####"); df.format(0.912385);   returns:  0.91238   However as you can see this uses half-even rounding. That is it will round down if the previous digit is even. What I'd like is this:  0.912385 -> 0.91239 0.912300 -> 0.9123   What is the best way to achieve this in Java?


I have a filter and label setup that has automatically added the label 'receipt 2009' to all my online purchases - yey!   Now I need to print them all, is there an easy way besides opening every email?

Attempting to securely download all the emails with a given label in Gmail, save them to a single file, and print that file.


We are trying to access/play audio files stored on external system from Salesforce Lightning Component. Access to file requires a BASIC authentication with GET method and we don't want users to prompt for username/password when they click on the audio file link (Stored as URL field on Salesforce custom  object). We first tried redirecting the user to audio file but no luck. Second option we are trying is, aura component as below which takes Blob from apex controller but it's not working. Any help is greatly appreciated. <aura:component> <audio src="{!v.audioFile} type="audio/x-wav">          autoplay="true"> </audio> </aura:component>  js controller     ({     doInit : function(component, event, helper) {         var recID = component.get("v.recordId");         console.log("recordID "+recID);         var action = component.get("c.makeCallout");                  action.setParams({             "recID":recID         })        action.setCallback(this, function(response) {             console.log('get state'+response.getState());             if (response.getState() == 'SUCCESS') {                 debugger;                var templateData = response.getReturnValue();                 var byteCharacters = atob(templateData);                 console.log(templateData);                                  const buf = new Array(byteCharacters.length);                  for (var i = 0; i != byteCharacters.length; ++i)                 buf[i] = byteCharacters.charCodeAt(i);                                  debugger;                                  const view = new Uint8Array(buf);                                  //cast to blob                 const blob = new Blob([view], {                 type: 'audio/x-wav'                 });                var audio = new Audio(blob);                 audio.play();                                  component.set("v.audiofile", blob);                 component.set("v.callOutComplete", true);             }         });         $A.enqueueAction(action);     }, })

I have added an mp3 file as a static resource, can someone please help me to call that resource in the lightning component so when I hit the button it will play that static resource  as per the Salesforce documentation I have tried below but instead of playing the sound it is displaying the message.