How do I analyze the correlation between Likert Scales?

I have 7 different Likert Scales each consisting of 4 Likert items. In other words, I have 7 variables (Likert scales) and 28 Likert items (questions).  I tested for reliability using cronbach's aplha and all likert scales were above 0.70. Now by putting the likert items together to build new variables do I use the mean or mode?  And lastly, I want to find the correlation between one likert scale and the rest of them? What kind of analysis should I use?   Thanks


JavaScript regex syntax highlighting issue

if(!/^https?:\/\//.test(val) && foo == 'bar') {     val = 'http://' + val; }   As you can see, the // causes the highlighter to switch to comment mode which is incorrect.


Find the value of $\sum _\limits{n=0}^{\infty }\:\left(\left(n+2\right)/2^n\right)$

Find the $\sum _\limits{n=0}^{\infty }\:\left(\left(n+2\right)/2^n\right)$   My Try: The answer is $6$ as $=\sum _\limits{n=0}^{\infty \:}\frac{n}{2^n}+\sum _\limits{n=0}^{\infty \:}\frac{2}{2^n}$,  I stuck at first part $\sum _\limits{n=0}^{\infty \:}\frac{n}{2^n}$. how it calculate $2$.  Can you please explain it?


Proving that the tangent bundle of the sphere is projective but not free

In my Commutative Algebra exercises I have the following exercise:  "Let $A = \frac{\mathbb{R}[x,y,z]}{\left\langle x^2+y^2+z^2-1 \right\rangle}$ and $M = \left\lbrace (\varphi, \chi, \eta) \in A \oplus A \oplus A : \varphi x + \chi y + \eta z =0 \right\rbrace$. Prove that M is a projective A-module but it is not a free A-module."  Seeing that it is projective is easy because $M$ is the kernel of the homomorphism $f: A \oplus A \oplus A \rightarrow A$ sending $(\varphi, \chi, \eta)$ to $\varphi x + \chi y + \eta z$. $f$ is surjective because $1=f(x,y,z)$ and so the sequence $$0 \rightarrow M \rightarrow A \oplus A \oplus A \rightarrow A \rightarrow 0$$is exact, but $A$ is a projective $A$-module so the sequence splits and $A \oplus A \oplus A  \cong M \oplus A$. Hence M is projective.  However, I can't figure out how to prove that its not free. I get the idea that $M$ something like the   algebraic tangent bundle of the sphere and we know from algebraic topology that the tangent bundle of the sphere is not trivial and since trivial bundle <-> globally free bundle, M shouldn't be free.  Even though I look for a commutative algebra-proof of the fact, any insights to the questions are welcome.


How to get rid of banners from Stack Exchange when not logged in?

If I view a Stack Exchange page without being logged in there are three banners which I have to remove first before browsing. The page looks for example like this:    That's totally unusable for me. As I remember those banners are a relatively new "feature".   Is there any trick to get rid of the banners when not logged in for example by tweaking some cookie settings in my browser or by blocking specific IP's in my hosts file (I am working with ubuntu 18.04)?


How to new a box in lua with luatex/lualatex?

I want to set a box register so I use \setbox180=\hbox{TEST} under the function tex.print and then use directlua to get its width. So This programme: \documentclass{article} \usepackage{luacode}  \begin{document}  \directlua{     function w(obj)         if obj == nil then             return "nil"         else             return obj.width         end     end }  I make three box that have widthes in% \setbox200=\hbox{TEST AND TEST}% \directlua{     tex.print("\string\\setbox180=\string\\hbox{AB}")     tex.print(w(tex.box[180]).." sp and "..w(tex.box[200]).."sp") }.  I make two box that have widthes in \directlua{     tex.print(w(tex.box[180]).." sp and "..w(tex.box[200]).."sp") }.  \end{document}  But the output is: I make three box that have widthes in nil sp and 5434245sp. I make two box that have widthes in 955515 sp and 5434245sp.  that means that the box in the directlua cannot be made in time but after when it exits the command. How can I make it? Is there other ways to assign the box register? Thank you a lot. (I edit it to make it run.  looks have the answer that I want)


How to fix Padding Oracle vulnerability on CentOS 7

I have set up a test web server on CentOS 7 to find a way to fix Padding Oracle vulnerability, which I got when I scanned our production site on ssllabs.com. On the test server, I installed openssl(1.0.2j, which is latest as of 1/12/2017) and apache(2.4.25, which is also latest as of 1/12/2017) from source and made some basic changes to apache configuration such as SSL. After making sure SSL works by accessing it with a web browser, I scanned the test site on ssllabs.com, which told me that it still had the same vulnerability. I thought the test site would pass it because the bug was already fixed at the release of 1.0.2h according to the Openssl official site. I have no idea what else to try next. Any advice would be appreciated.  I think the apache uses the openssl I installed instead of the other one (1.0.1e), which is built in on CentOS7. Below is one of what I did to make sure of that.  Under the condition of ServerTokens Full  [root@*** ~]# curl --head http://***.*********.com HTTP/1.1 200 OK Date: Thu, 12 Jan 2017 19:52:31 GMT Server: Apache/2.4.25 (Unix) OpenSSL/1.0.2j Last-Modified: Mon, 11 Jun 2007 18:53:14 GMT ETag: "2d-432a5e4a73a80"  Accept-Ranges: bytes Content-Length: 45 Content-Type: text/html


What are the relative strong and weak points between tcolorbox and mdframed?

I think practically we will not use both tcolorbox and mdframed in a single input file. Correct me if I am wrong. So we have to choose either tcolorbox or mdframed. However, without knowing the strong and weak points of both, we can only choose one by gambling.  Shortly speaking, what are the weak and strong points of both packages? The answers really influence the path of my life in TeX.


Difference between relationship and relations?

Which is the correct statement?     She has outstanding interpersonal relationship with the group?     or     She has outstanding interpersonal relations with the group?


Intuitve examples of importance sampling

My background is computer science. I am fairly new to monte carlo sampling methods and, although I understand the math, I have hard time coming up with intuitive examples for importance sampling. More precisely, could someone provide examples of:   an original distribution one cannot sample from but one can estimate an importance distribution which can be sampled from and adequate for this original distribution.   Thanks in advance!


$f(x)=\int_{0}^{x}\cos(1/t)dt$  Then$f'(0)=?$  I tried $f'(x)=\cos\left(1/x\right)$, but then I get into trouble.  Hope for your help


Why does "AMD testing use only" pop up upon login?

I have just used this  to follow some of the steps to manually create the .deb file from the .zip file that is on the AMD site. Then I installed them one by one using the Debpackage installer. So I didn't used the command line, but the graphical interface of my OS.  The problem is that when I log in I get this message: "AMD Testing use only"  Here is my fglrxinfo:   :~$ fglrxinfo display: :0  screen: 0 OpenGL vendor string: Advanced Micro Devices, Inc. OpenGL renderer string: AMD Radeon HD 6500M/5600/5700 Series OpenGL version string: 4.2.12337 Compatibility Profile Context 9.01   Have I done something in the wrong way?


How to create a 1280x800 screenshot of a Chrome Browser viewport

The  requires screenshots of the exact size 1280x800.   Using the system-built-in screenshotter, I have often failed by a few pixels, which required tedious  image cropping by hand or the convert tool.  How are those easily created?


Beta coefficient interpretion with categorical and continuous predictors in a linear regression

I am trying to run a linear regression with both categorical and continuous predictors. I have coded the categorical predictor (with three levels) into three dummy variables, and entered the two dummy variables into the regression along with the continuous predictors. My question is: How do I interpret the beta coefficients of the categorical predictors? I can interpret the other beta coefficients from the continuous predictors as "_% of the variance in x can be explained by y" but I am not sure how to interpret the beta from the categorical predictors. The t statistic for both of my dummy variables were significant, but I'm having difficulty interpreting it in the context of the full regression. Any help would be appreciated!  Thank you!


The difference between for and over in terms of time

This is my first question. So please go easy on me if possible.   I can't understand the difference between 'for' and 'over' in terms of time.  For example, What is this difference: 'The birth rate has been increasing over ten years', and 'The birth rate has been increasing for ten years'.  If I can give you another example, what is the difference between 'for centuries' and 'over centuries'.  Maybe this is a very easy question but I can't find out the difference. Please help me.


Translucent effect to section of webpage

I have a background image for my webpage and I have this  HTML:

Hello World

    CSS:  .front{     background-color:silver;     height:200px;     width:200px; }   The width & height of div is 200px,200px.I want the area covered by the div element to be translucent ie. showing the blur background, but the text that div contains should be clear as well. How do I do that?


apply gdal to calculate raster that is already in qgis raster calculator

I am using the following code in qgis to calculate some raster.It is not giving the correct result as it is in arcpy.I want to apply same in gdal.Can anyone help me how to use the gdal api.Please give me code  from qgis.analysis import QgsRasterCalculator, QgsRasterCalculatorEntry layer= iface.activeLayer() entries = [] # Define band1 ent1= QgsRasterCalculatorEntry() ent1.ref = 'boh@1' ent1.raster = layer ent1.bandNumber = 1 entries.append( boh1 )  # Process calculation with input extent and resolution calc = QgsRasterCalculator( 'boh@1 * 0.03705882+ 3.2',                              'D:\test\testtif',                              'GTiff',                             layer.extent(),                              layer.width(),                              layer.height(),                              entries )  calc.processCalculation()


Black card ability - all players exile a creature - does it work on the one with protection from black

Let's assume I have black card with "player must exile a creature" and one of mine opponents have only one creature on the battlefield, but it has "protection from black".  Does mine card affect his?


How can I manually generate a random number from a given distribution, as for instance, 10 realisations from the standard normal distribution?


So I recently discovered the --s2k mode in gpg.  Sadly it is not very well-documented. I mean, what is s2k even supposed to mean?  Could someone explain to me the purpose and detailed function of s2k?    Is --s2k-cipher-algo even necessary in a symmetric encryption scenario where you define the cipher separately?  What exactly  does --s2k-count do?  What does the number after --s2k-count do? What does it indicate and why is 65 million the highest number? 65 million of what? What is done so many times?


notify-send not working from script - but works from CLI

Good Day,   I am new to Linux (Raspberry) and am trying to get notify-send to work from a script (see below).  Notify send works from the terminal CLI and displays on my GUI.  But it does not work from the script.   I am using Raspberry Buster - with all updates.  #!/bin/bash  # This should point to the pivoyager executable PIVOYAGER=/usr/local/bin/pivoyager  while true; do    # Phase 1: Check every 5 seconds if we are USB powered.    #          If we are not on USB power, go to phase 2.    while $PIVOYAGER status flags | grep "pg";    do       sleep 5    done      # Phase 2: Do something before shutdown. (optional)    #          e.g. send an email, warn users, etc.    #notify-send "We are on Battery Power.  Save all your work."    sleep 30       # Just check if power was miraculously restored.    if ! $PIVOYAGER status flags | grep "pg"; then       break    else       notify-send "Power was restored. Shutdown aborted!"    fi done  # Phase 3: Initiate the shutdown. #          - Enable automatic power on once USB power is restored. #          - Program full power cut in 25 seconds. $PIVOYAGER enable power-wakeup $PIVOYAGER watchdog 25 sudo shutdown now   Thanks in advance for your help.


Interpretation of significant interaction term, but insignificant joint effect

I have a very basic interaction model with this setup: Y = $\beta_0$ + $\beta_1$ Var_1 + $\beta_2$ Var_2 + $\beta_3$ Var_1 * Var_2 + Controls + $\epsilon$  Y = Continuous variable Var_1 = Continuous variable Var_2 = Indicator variable (i.e., 1 or 0)  In this model, $\beta_3$ is significant--but joint test of $\beta_1$ + $\beta_3$ (i.e., when Var_2 = 1) is insignificant. How do I interpret the interaction term when the total effect isn't significant? Edit: My post has been identified as a potential duplicate, but I don't think that this is the case because those links appear to be concerned with the interpretation of main effects when an interaction effect makes the main effects insignificant. I'm interested in the interpretation of a significant interaction effect when the total effect (i.e., $\beta_1$ + $\beta_3$) is insignificant.


E-Mail notification when hard disk full?

Is there an easy way to set up E-Mail notification when a Windows 2008 server's hard disk is getting full?


How can I run a shell script in Windows?

I'm a Mac user and new to Windows. How can I execute a shell script in Windows?   Generally, I would save the text file with the extension .sh and run it via Terminal. But how could I do that in Windows?


integrate the following function: $\int_{0}^{\infty} \frac{\log{x}}{x^{2}+a^{2}} \ dx$

How do I integrate the following function: $$\int_{0}^{\infty} \frac{\log{x}}{x^{2}+a^{2}} \ dx $$ Integrating by parts looks very difficult.


Having problem with installing npm in ubuntu 16.04.3

After installing node.js I execute this command:  sudo apt-get install npm   And getting error:  The following packages have unmet dependencies:   npm : Depends: node-gyp (>= 0.10.9) but it is not going to be installed E: Unable to correct problems, you have held broken packages.     $ sudo apt-get upgrade -f npm node-gyp Reading package lists... Done Building dependency tree Reading state information... Done Calculating upgrade... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies:   nodejs-dev : Depends: libssl-dev (>= 1.0.0g) but it is not going to be installed E: Broken packages


converting a date in ruby to a customised format

I am looking for a method where I can convert a date into more of a human readable format... for example:  12/02/2013 can be converted to "2nd December 2013" 12/03/2013 should be converted to "3rd December 2013" 11/27/2013 can be converted to "27th November 2013"  Is any function in Ruby/Rails readily available to use or I have to write on my own something to handle "st","nd","rd" and "th" besides date numbers ?


Divisibility via Induction: $8^n\mid (4n)!$

I have to prove by induction the following fact:  Show that $(4n)!$ is divisible by $8^n$.  My stab at the solution:    I have a slightly bad feeling about this solution and I would like if someone would point me to my possible (more than likely) error(s).  Thank you,  Bayerischer


Can I call a function in Python using a series of predefined arguments?

Let's say I have a tuple  t = (1, 2, 3)   and a function  def test(a, b, c):     print a + b + c   I could then call  test(t[0], t[1], t[2])   Is there a more elegant way to do this for a large tuple (or other data type, e.g. list)? Like so:  test(t.unpack_as_args())   What syntax can I use in place of t.unpack_as_args()?


"Disable Cache" no longer works in MacOS 10.12

Mac OS 10.12.1 Safari 10.0.1 Develop Menu enabled Disable Cache checked  Safari's cache is full of garbage as pictured.  For the past few years "Disable Cache" has blocked all this nonsense, but since upgrading to Sierra it no longer works.   Any ideas why or solutions? I can lock the cache file as a solution, but not as an answer.   Thanks!


Large sample - statistical significance with minimal differences

Small disclosure I am doing a course that requires learning statistics but it is not my field of expertise so I may make several mistakes, apologies in advance. Also, I will add some background as suggested, but the question is at the end of the post if someone does not want to read everything. The Dataset I have a large dataset I got from Kaggle with 8000 observations of different individuals. Each individual has 4 binomial attributes (so 1 or 0), i.e. Male (1) or Female (0). There are 5 other columns with continuous variables, i.e one is "average number of characters per post". What I am trying to understand I wanted to see if for each of these continuous variables there were significant differences among the different groups (so for each attribute). Process This is where I am less confident about. I thought it would make sense to do the non-parametric Mann-Whitney U Test to compare each group. However, since I am comparing 4 pairs of categories simultaneously, I thought that it would be sensible to adjust the obtained p-values to prevent an increased risk of committing a type 1 error. So I thought of using the Bonferroni correction (if this makes sense...) The results So I decided to start comparing Group A and Group B for the category "Average Number per Posts". The Mann-Whitney Test gives me the following statistic and p-value: Statistics=-25707067.000, p=0.000 The problem is that when I look at the data, this result seems to be very far fetched, here are some descriptive statistics and a box plot:   For me, the groups are almost identical, I would have guessed that I would not have found grounds to reject the null hypothesis. Question I am a bit lost trying to understand the reason behind these results. With such a large sample, can these minor differences give a significant p-value? I guess that statistical significance does not mean that something is relevant in real life but are these results possible or most likely a consequence of a mistake I made in the process? Should I have done something different? Possible mistakes?  Result of a bad study design and statistical process Result of bad programming (this will be impossible for you to determine but I guess it's possible) Correctly computed but misinterpretation of the results Combination of the previous or other  Any way, thanks and sorry for the long post.


What kind of fallacious reasoning is "You're not a girl, so you can't understand girls problems"

Today someone told me : "You're not a girl, so you can't understand girls problems".  What kind of fallacy/sophism is this ?


apex method for logout from force.com site

I'm using a force.com site and it has a login method that allows you to redirect them to different landing pages from within apex via Site.login(username,password,url). However it appears there is no Site.logout() method. Its my understanding that logout is configured via the customer portal settings and then called using {!$Site.Prefix}/secur/logout.jsp.  My issue is what if I want to redirect the user to different logout pages conditionally? Is there any way to do this or am I stuck using only the URL in the customer gateway settting.  Thanks!


The normalizer of $G < S_n$ in the group $S_n$ is defined as $$N_{S_n}(G) = \{\pi \in S_n \mid \pi G = G \pi \}.$$ The group $G$ is self-normalizing in $S_n$ iff $$N_{S_n}(G) = G.$$  What are the self-normalizing subgroups of $S_n$?  This is equivalent to asking: Given a subgroup $G < S_n$, under what condition it is not a normal subgroup of any other $H \leq S_n, G\neq H$?


All of my UWP app icons are blank/empty/missing in the start menu search only. They appear correct in the start menu list itself, in settings. Some are missing in the taskbar as well, some are not.    I am using sagethumbs for some file extensions, but I disabled it and the issue persisted (after restarting Windows Explorer). I cleared the icon cache, still no luck.  Anyone know a fix for this?  I am using Windows 10 (1803 - Build 17134.112)


Danger of setting all initial weights to zero in Backpropagation

Why is it dangerous to initialize weights with zeros? Is there any simple example that demonstrates it?


Dell 1397 WLan Mini-card does not recognize particular wifi in both recently installed dual-boot Ubuntu 16.04 and Windows 7

Very grateful to the comunity and this post  which I think is the product of many invisible works, so thanks. I will not be posting this question if I didn't think it could be useful, regardless of the simplicity or complexity, and ignoring that maybe it was posted previously; if this is the case excuse in advance.  The title practically describes the entire issue, to clarify I checked in both OS that the wifi-card drivers are installed and actualized. I can see other wifi nets but not my own.  When reseted the router a re-configuration was made, lowering the WiFi standard from 802.11g to 802.11 b (I guess this is correct, which I'm sure is that the change was made from higher to lower hierarchy standard). After this change I was able to detect and connect to the wireless in both Ubuntu and Windows, but now once I reboot I can not see my wireless account anymore.  Below the output of   wget -N -t 5 -T 10 https://github.com/UbuntuForums/wireless-info/raw/master/wireless-info && \ chmod +x wireless-info && \ ./wireless-info    And a caption of the modem specs


Unsure of what this tube is on wired motor

Upon looking for an answer online I found none, maybe it was the way I was describing it I don't know, on to the point though. On VEX robotics motors there is a tube with the wire looped in through it, here is a picture    It is covered with heat shrink tubing I believe and the inside of it is some sort of metal/ceramic that is more brittle. Maybe it's some sort of resistor because I think the materials of the inside of the resistor and tube are the same. Also there is no tag for Electric Motor yet, maybe should be added for those with 300 rep.


Problem File ended while scanning use of \field. \begin{document} when compile

EDIT 1:  is the full code, including .tex and .bib files. Any help?  I'm trying to write an article, but all day I've been compiling and always everything goes wrong. I wrote a little code for the example:  \documentclass[10pt,a4paper]{article} \usepackage[utf8]{inputenc} \usepackage[T1]{fontenc} \usepackage[ backend=biber, citestyle=authoryear-comp, bibstyle=authoryear,         giveninits=true,             maxcitenames=2,              uniquelist=false,            sorting=ynt,                 sortcites,                   maxbibnames=99,  url=false, eprint=false, dashed=false,                ]{biblatex} \addbibresource{References.bib} \begin{document}  \section{Introdução} \parencite{Paerl2009} \parencite{Pantelic2013} \end{document}   The references are stored in the References.bib  @Article{Paerl2009,   author   = {Paerl, H. W. and Huisman, J.},   title    = {Climate change: a catalyst for global expansion of harmful cyanobacterial blooms},   journal  = {Environmental Microbiology Reports},   year     = {2009}, }  @Article{Pantelic2013,   author   = {Pantelic, D. and Svircev, Z. and Simeunovic, J. and Vidovic, M. and Trajkovic, I.},   title    = {Cyanotoxins: characteristics, production and degradation routes in drinking water treatment with reference to the situation in {Serbia}},   journal  = {Chemosphere},   year     = {2013}, }   Always when I compile, I get     File ended while scanning use of \field. \begin{document}   Any hint whats going on?


Accidentally ejected External drive while downloading file, now having problems reading

I'm hoping someone can help! I recently downloaded a torrent directly onto an external hard drive, (using a 2009 MacBook Pro and 1TB Seagate Expansion portable Drive) somehow during the download the drive was accidentally ejected, since this incident when I plug the drive back in it’s having problems reading.  The drive works fine for about 10 minutes, I can read/copy/paste and access files but then starts to wreak havoc; apps hangs, it hangs the Finder, etc.  I’ve tried repairing it in Disk Utility, which reads and repairs this disk but problems inevitably continue as described above.  I’ve deleted the Torrent file also. All my files on this external drive so re-formatting is not an option until I can retrieve them.


Is it possible to create a shortcut for forward delete?

Before I get downvoted and castigated - yes - this question has been asked (link below) but was not answered.  So, like the title suggests, does anyone know how to create a forward delete button using special keys on Ubuntu?  Thanks  previous link:


Intel/AMD hybrid graphics on Ubuntu 16.04: How activate the other one?

My laptop has two GPUs: an integrated intel and a Radeon HD 8550M. The latter is from . According to the manual of the open source Radeon driver, these series are supported by the driver. I want to use the Radeon GPU, but the integrated GPU is being used by ubuntu and the applications, and I don't know how to activate the Radeon. Thanks.


I want to make following Software architecture inside TikZ:    See below my code:  \documentclass[border=2px]{standalone} \usepackage[utf8]{inputenc} \usepackage{tikz} \usetikzlibrary{shapes.geometric, arrows}  \tikzset{     green/.style  = {draw, rectangle, minimum width=1cm, minimum height=1cm, text centered, text width=1.2cm, font=\footnotesize, draw=black, fill=green!30},     blue/.style   = {draw, rectangle, minimum width=6cm, minimum height=1cm, text centered, text width=5.0cm, font=\footnotesize, draw=black, fill=blue!30},     yellow/.style = {draw, rectangle, minimum width=6cm, minimum height=1cm, text centered, text width=5.0cm, font=\footnotesize, draw=black, fill=yellow!30}, }  \begin{document} \begin{tikzpicture}[node distance=1.1cm]     \node (r1c1) [green] {VC++};     \node (r1c2) [green, right of=r1c1, xshift=0.5cm] {VB.NET};     \node (r1c3) [green, right of=r1c2, xshift=0.5cm] {C\#.NET};     \node (r1c4) [green, right of=r1c3, xshift=0.5cm] {Others};     \node (r2c1) [blue,  below of=r1c2, xshift=0.8cm] {COM-API Interface};     \node (r3c1) [yellow, below of=r2c1] {Autodesk Inventor Application};      \draw (r1c1);     \draw (r1c2);     \draw (r1c3);     \draw (r1c4);     \draw (r2c1);     \draw (r3c1); \end{tikzpicture} \end{document}   Below is the generated diagram:    The modules inside generated diagram are not properly aligned. Any suggestions please?


Ubuntu desktop not loading and only booting to command line

I have been trying to solve this problem on my Ubuntu 18.04 for the past two days.  I boot up my system, and it acts like the server edition of Ubuntu. It launches a full screen command line and that's it.   So far, I have tried reinstalling gdm3 and lightdm. That did not work. I set my privileges on the .Xauthority file to my username, that did not work. I also reinstalled gnome-panel as some people said and that did  not work. Finally, I installed lubuntu-desktop, and set LXDM as my default desktop environment. It's still only loading the command line!   What else can I try?


There is a problem which i tried a lot but didn't reach to any conclusions:How can i show that the highest power of n which is contained in $(n^r-1)!$ is $\frac{n^r-nr+r-1}{n-1}$?My try:$(n^r-1)!$=$(n^r-1)(n^r-2)(n^r-3)\cdot\cdot\cdot\cdot3.2.1$.But what next can i do?


Automatically citing all entries with keyword

Is there a way with biblatex to automatically cite all papers with a certain keyword or from a certain resource, while keeping the original citation order and adding the uncited publications at the end?  The usual way, i.e. with \nocite{*}, includes all resources, which is definitely not wanted and would include other1 in the example below. Putting a \nocite{*} in a refsection, the citation markers are not related to the main text.  \begin{refsection}{lib-own.bib}   \nocite{*} \end{refsection} \printbibliography[...,section=1]     \documentclass{scrartcl} \usepackage[style=phys,biblabel=brackets,pageranges=false,backend=biber,sorting=none,defernumbers=true]{biblatex} \usepackage{filecontents}  \begin{filecontents}{lib-own.bib} @article{own1,     author = {John Doe},     title = {First pub},     year = {1993},     keywords = {mypub} }  @article{own2,      author = {John Doe},     title = {Second pub},     year = {1994},     keywords = {mypub} }  \end{filecontents} \begin{filecontents}{lib-other.bib}   @article{other1,     author = {Otto Maler},     title = {First ref},     year = {1993}   }    @article{other2,      author = {Peter Schuster},     title = {Second ref},     year = {1994}   }  \end{filecontents}  \addbibresource{lib-own.bib} \addbibresource{lib-other.bib}  \begin{document}  \cite{own1}\cite{other2}  \printbibliography[keyword={mypub},heading=subbibliography,prefixnumbers=S,title=publications] \printbibliography[notkeyword=mypub,heading=subbibliography,resetnumbers=true,title=references]  \end{document}


Why Magnifying glass(convex lens) produces heat when placed in front of sun?


How to hide any div inside html form if internet is not availaible

Hello Guys I would like to know if it is possible to hide the div if the internet is not availaible. Here is the code    if(navigator.onLine) {       //show } else{ //Hide }      Thanks in advance.


Unexpected problem with a simple code that creates nested lists

I wrote a really simple code to create some nested lists, and I got an unexpected problem, that while loop doesn't end.  Have no idea what is wrong in it. If you have any clues, would much appreciate it)  import random  square = [0,0,0,0,0,0,0,0,0] squares = []  def allsquares():     for i in range(9):         squares.append(square)     return squares   def autofill():         for i in range(9):             fn = random.randint(1,3)             sn = random.randint(6,8)             for s in range(fn,sn):                 print('Mary Sue')                 d = True                 while d:                     x = random.randint(0,8)                     print(x)                     if squares[i][x] == 0:                         d = False                 squares[i][x] = random.randint(1,9)         return squares    allsquares() autofill() print(squares[2])


How to be granted root rights while browsing files/directories with Nautilus

I'd like to know if there a way to be granted root rights while using Nautilus 2.30 ?   For example I'd like to move some old folders of long unused users from the home directory - remains of previous distros (Debian).   Of course I can open a terminal, but I want to know if it is possible to do that with a mouse in Nautilus.


Depicting multiple point features in same location using ArcGIS Desktop?

On a map that I am creating (in ArcGIS Desktop 10), I need to include symbols for point features that are sometimes right next to (or even on top of) each other. This, of course, creates potential for all sorts of clutter or even for some features to not be displayed at all when zooming out.   I am thinking of positioning the symbols in a neat row (or column) off to the side and having some kind of arrow point from them toward the features' actual location. Is there some kind of symbology setting for this in ArcGIS (I want to be sure that the distance between the symbols is always consistent every time this is done), or do I have to align the symbols and draw the arrow (or whatever the proper term is) by hand?


How do I increase the size of swapfile without removing it in the terminal?

Is there a way to increase my existing "swapfile" without having to destroy and re-create it? I would like to up my swap space from 1GB to 2GB.  Currently it is set up as such:  $ sudo swapon -s Filename                Type        Size    Used    Priority /swapfile               file        1048572 736640  -1 $ ls -lh /swapfile -rw------- 1 root root 1.0G Nov  9  2016 /swapfile   I'm using Ubuntu 14.04.


How can I integrate $$\int_{\frac{\pi}{6}}^{\frac{\pi}{3}}\frac{1}{1+\sqrt{\tan x}}dx\ \ \ ?$$   I have made the integral into the form of $\frac{\sqrt{\sin x}}{\sqrt{\sin x}+\sqrt{\cos x}}$, but been able to go no further.


What is the meaning of public stock price data from before the official first day of trading?

I have noticed that some companies, in the weeks prior to a first listing day or IPO, have share prices listed. This often seems to happen before a spinoff, such as in Xylem's (XYL) 2011 spinoff from the ITT Corp. According to , XYL began trading under its own ticker effective Nov. 1; however, Yahoo and Google have price information . Another case is YUM Brands (YUM). I'm not as certain of the official ticker launch date for YUM spinning off from Pepsi, but Crunchbase lists it as Sep. 26, 1997; Google and Yahoo have .  I'm wondering how to interpret these prices. Are they OTC or privately traded prices from early shares, that are incorporated into the public price once trading begins? Are they somehow derived from the share price of the parent corporation? Is the "official ticker start date" somewhat fungible, and is public trading of these entities already occurring? Or is it something else?  I have observed this mostly with spinoffs, I believe, but there may be other situations where this pattern occurs.


hide element whit javascript dom and remove the empty spaces

This is my code but it's not good because they do not line up. I have to remove the empty spaces, and group the process bars    function clickMe(abc) {   var v = document.getElementsByClassName(abc);   hidden('.progress');   for (var i = 0; i < v.length; i = i + 1) {     v[i].style.visibility = 'visible';   } }  function hidden(elemnt) {   var hide = document.querySelectorAll(elemnt);   for (var i = 0; i < hide.length; i = i + 1) {     hide[i].style.visibility = 'hidden';   } }   When I click, I compare


Can anyone tell me how to interpret the 'residuals vs fitted', 'normal q-q', 'scale-location', and  'residuals vs leverage' plots?  I am fitting a binomial GLM, saving it and then plotting it.


4 (sub) Subfigures + 1 Subfigure side by side

Here is what I have tried. For reproducibility I have used [demo]. I want the plots on the right to be neatly placed and of the same height as the one on the left.   \documentclass{article} \usepackage{caption,subcaption} \usepackage[demo]{graphicx} % demo is just for the example  \begin{document} \begin{figure} \centering \begin{subfigure}[b]{.45\textwidth} \includegraphics[width=\textwidth,height=5cm]{/home/ayan/Programs/David_Parkinson/Reduced_Reshaped/Elbow.pdf} %\caption{A tall figure} \end{subfigure}\qquad \begin{subfigure}[b]{.45\textwidth}     \begin{subfigure}[b]{.45\textwidth}         \includegraphics[width=\textwidth]{/home/ayan/Programs/David_Parkinson/Reduced_Reshaped/ML_Data/BIN_1/KMeans_Cluster_1_hist.pdf}         %\caption{}\label{}     \end{subfigure}     \begin{subfigure}[b]{.45\textwidth}         \includegraphics[width=\textwidth]{/home/ayan/Programs/David_Parkinson/Reduced_Reshaped/ML_Data/BIN_1/KMeans_Cluster_1_hist.pdf}         %\caption{}\label{}     \end{subfigure}     \begin{subfigure}[b]{.45\textwidth}         \includegraphics[width=\textwidth]{/home/ayan/Programs/David_Parkinson/Reduced_Reshaped/ML_Data/BIN_1/KMeans_Cluster_1_hist.pdf}         %\caption{}\label{}     \end{subfigure}     \begin{subfigure}[b]{.45\textwidth}         \includegraphics[width=\textwidth]{/home/ayan/Programs/David_Parkinson/Reduced_Reshaped/ML_Data/BIN_1/KMeans_Cluster_1_hist.pdf}         %\caption{}\label{}     \end{subfigure} \end{subfigure}\qquad  \caption{The full caption} \end{figure} \end{document}


What's the difference between denizen, resident, inhabitant?

What's the difference between , , and ?  Even if their ODO definitions suggest they are interchangeable most of the time, are there fine differences in meaning between them?


why does free command show more memory usage than other tools

When I use free -h -l  command I see 1.8G in use where system monitor app shows me 1.1G in use.               total       used       free     shared    buffers     cached Mem:          1.8G       1.7G       161M       245M        67M       553M Low:          853M       735M       117M High:         1.0G       963M        44M -/+ buffers/cache:       1.1G       783M Swap:         3.8G       1.4G       2.4G


Indian Passport first page ripped - is this considered 'damaged'?

Hi All, My passport first page got ripped. Front side of this page has a Indian emblem and backside is a blank with no stamps or Visas. Other pages including visas, personal details, POE stamps everything looks good. Basically a brand new passport with more than 7 years validity. Will this be considered as damaged? Please help me with your answers ASAP as I have a travel plan to India end of this month for my own wedding.   This damage happened accidentally when I was scanning the pages.


Dinamically created elements with ng-angular didn't trigger onClick event

I've got some cards (forms) created with ng-angular based on Array list. On each card i have onClick event which doesn't trigger. If I copy paste the function code on browser console, all events work ! I guess that events aren't bind when the DOM is fully loaded.  These are my functions :          $('.floating-open').on('click', function () {         var $this = $(this);         $this.parents('.clickable-button').addClass('clicked');         $this.parents('.clickable-button').next('.layered-content').addClass('active');          setTimeout(function () {             $this.parents('.card-heading').css('overflow', 'hidden');         }, 100);      });      $('.floating-close').on('click', function () {         var $this = $(this);         $this.parents('.layered-content').prev('.clickable-button').removeClass('clicked');         $this.parents('.layered-content').removeClass('active');          setTimeout(function () {             $this.parents('.card-heading').css('overflow', 'initial');         }, 600);      });   Thanks in advance for your help


Disable CTRL+ALT+F4 switching to virtual terminal

Is there a way that I can stop the Ctrl+Alt+F4 key combination from switching to a virtual terminal?  I still want the other key combinations to switch to terminals - I just want to change the F4 one because I often use that keyboard shortcut in a Windows VM.


Terminal Page Down and Page Up For Laptop without PgDn and PgUp Keys

I understand Terminal by default doesn't support PgDn and PgUp but is there an alternative to the linux terminal that supports this?  Cygwin has an option to enable this so I would assume linux does also.  EDIT:I have changed the location of my page down and page up on my keyboard and this appears to not work there. I do not have page down and page up keys on my keyboard.


The number of (non-equal) forests on the vertex set V = {1, 2, ...,n} that contains exactly 2 connected components is given by $\sum_{k=1}^{n-1} {n-1 \choose k-1} k^{k-2} (n-k)^{n-k-2}$.  I am unsure how to approach this question. Could someone guide me through the proof? If G is a spanning tree and it is disconnected then I know it is a spanning forest. Also, I know by Cayley's thm that there are $n^{n-2}$ nonequal tree on a vertex set V = {1, 2, ...,n} which is where i'm assuming the $k^{k-2}$ comes from but I do not understand where the rest of it is coming from.


Can somebody, please, explain how to prove this theorem: If every vertex of a planar graph has an even degree, it’s 2-colourable. I understand that we can make a dual graph out of original. The number of vertices will be the same as number of faces in the original graph. The number of edges will be the same as in the original graph. But what should I do next to prove the theorem?


Need to compare the two files and print all the columns then missing display as NA, then join another file

File 1:  123, 234 345, 789 678, 900   File 2  123, abc 345, dnc   output (all columns in file1 and missing value in file two as NA):  123,234,abc 345,789,dnc 678,900,NA   Output file  add with another file   File 3  123, 2014/10/20 678, 2013/02/30   Output file  123,234,abc,2014/10/20 345,789,dnc,NA 678,900,NA,2013/02/30   There are such 10 files which I need to add to the 1st file


Does a high aperture impact exposure differently than a high shutter-speed?

Context: I am trying to shoot images that bear a black background /low-key. So I'm trying to understand this subject better.  Edit: I would like to emphasize that this question is being asked with a specific end-result in mind, low-key/ black bg.  I have ready that 'increasing the shutter speed helps control ambient light whereas the aperture helps control the strength of the external flash reaching the sensor.'  I am thus trying to think along these lines. Hope someone can help.


What to expect when pursuing a second doctorate in an unrelated field

Long story short: I got a PhD a few years ago (let's say, in numerical methods for nonlinear PDEs).  I've since gotten experience with a couple post-docs and a variety of collaborators, but I'm not really satisfied with what I'm doing.  I feel out of place.  Earlier in life, I made a tough decision between science and humanities-- my other passion has always been, let's say, east Asian languages.  If my bachelors program had had better language courses or options for "hybrid" fields like computational linguistics, I probably would have gone that route, instead of fully focusing on math.  I've sought out collaborations that might help me bridge the gap between math and languages; I've also looked at postdocs to help make the transition.  I've reached out to leaders at research groups who do stuff I'm really interested in.  The common denominator is: I'd need a PhD in some kind of linguistics to research seriously what I want. So...  What key things should I take into consideration when pursuing a doctorate, given that I have a doctorate in an unrelated field?  Please consider the question within the following context: I'm not asking whether having two PhDs is good or bad (I frankly don't care), how to needlessly pad my name with titles, or how to get two PhDs simultaneously. (That is all to say:  doesn't answer my question.)  I'm asking about what to expect when changing careers, specifically, if the source career is in one academic field and the target career is in another, unrelated field.  Assume I've 100% decided to leave my current field and pursue this second doctorate, for the purpose of changing careers. Assume also that I already have substantial content knowledge in the target field, as I have a bachelors degree in it already, and it's been an avid hobby for most of my life.  Some sub-questions that don't need to be specifically answered, but I think help narrow the question: in what way could my current PhD be a hindrance in getting into a new program?  Will my supervisors and colleagues see my past PhD as an asset, or as weird-looking mole they will try to politely ignore?  What are other questions should I ask myself to prepare for such a non-traditional career path?  Note: I've edited this question multiple times in a vain attempt to get the duplicate label removed. If you agree, please vote.


Is there a way to find prices from departure city to multiple cities or countries at once?

I'm looking for airline ticket prices, and since my route around Europe is essentially one big circle, it doesn't really matter where I start. I just want to find the cheapest tickets that will get me to Europe. Is there a way to look for airline prices for City ABC to Europe? Or City ABC to a list of any of these 30 destinations? (The choice of 30 was arbitrary, but I was thinking of pooling a list of all capitals or major cities in my route and including all the airports within, say, a 25 mile radius of each of those cities).  As of now, I'm just doing city by city and it's making it difficult to compare prices.


Run Full Ubuntu Installation from UEFI Bootable USB stick

Similar to a previous questioner who did not appear to get an appropriate answer (being referred to a page that did not relate to his specific need) I wish to run a full 64bit version of Ubuntu 13.10 from my 64g USB3 stick. OK, I have actually done this, no problem.  But the issue is I would like to be able to boot from this large USB stick onto my UEFI laptop, running Win 8.1, which, of course won't recognise it without me changing the setup in a way that won't let me run Win 8.1 without changing the setup back again. Messy. I've already created a 'Live' 64bit Ubuntu 64bit 13.10 installation on another USB stick which I definitely know I could use to install Ubuntu onto a new partition on my UEFI - Secure Boot Win 8.1 machine. But I don't want to do that.  I simply want to run full Ubuntu from my large format USB stick on that machine - and I don't know a way of making that stick UEFI bootable at the same time as installing Ubuntu on it again (or diddling with the existing installation, if necessary). The problem is that I'm obliged to create any new installation on this stick via an old non-UEFI computer. I can't do it via my Win 8.1 machine. So I just to not get any option via the 'Something Else' installation method to choose EFI. Phew! Anybody know what I can do (apart from take a running jump)? David


Is it possible to power a cordless drill from wall socket adapter?

I have a dewalt 18V cordless drill. I am wondering if it is feasible to build an adapter that can power the drill from a standard US wall socket?  A typical DeWalt drill needs 2.6 amps with no-load. I am assuming this jumps significantly higher under load. Most DeWalt motors have a stall current over 250 amps...  Any insight would be greatly appreciated!!


snap packages error "multiple nvidia drivers detected, this is not supported"

This issue happened after running updates. I've checked the system but only one Nvidia driver seems to be present. Purging / reinstalling the Nvidia drivers didn't fix it. Nor did purging / reinstalling the snap system. Could it have something to do with nvidia-prime? How does it check for the issue?


You lose 10% of your pixels every time you die. Is there anyway to put your pixels away so that when you die you don't lose as many?


$f$ holomorphic on $D\setminus \{0\}$ and takes no values in $(-\infty,0],$ then $0$ removable

If $f$ is holomorphic on $D\setminus \{0\}$ and takes no values in $(-\infty,0]$ then $0$ is a removable singularity.   I thought to prove this by elimination, but I can't really tell anything about the behavior of $f$ around $0$. How can one translate the information about the definition of $f$ in semi-open interval $(-\infty,0]$.


What will become of Ar-Pharazôn and his men?

I've been reading through a book (I think it was The Complete Guide to Middle-earth by Robert Foster) and I'm uncertain what the ultimate fate of the Numenorians who invaded Aman will be?  Ar-Pharazôn made a huge error in invading Aman with a massive force of men, but they were buried under mountains if I remember correctly. Is this punishment forever or will they be able to redeem themselves?  Will they be allowed to take part in the final music with the rest of men or will they remain trapped forever?


I'm travelling to Orlando for 14 nights at the end of August, for a nice holiday break. I travelled to Orlando last year in June, for 2 weeks. My question involves whether my visa waiver is still valid?  If so, do I just print it off again and take it to the airport in August, My hotel details will be different than last time? Is that something to be worried about?  Thanks


Another Proof for Center of Non-Abelian Group of Order $pq$ is $\{e\}$

I want to show that  If $G$ non-abelian group of order $pq$ with $p,q$ primes then $Z(G)=\{e\}$.  It's immediate that if $Z(G) \neq \{e\}$ then $|Z(G)|=p$ or $|Z(G)|=q$ and using that any group of prime order is cyclic then $G / Z(G)$ is cyclic, which implies that $G$ is abelian and therefore we have a contradiction. I wanted to know if it's possible to prove it without using the theorem that if $G/Z(G)$ is cyclic then $G$ is abelian because my professor hasn't mentioned it before. Any help would be greatly appreciated.


I want to add a shortcut to a file in another directory (where it isn't located). How do I do that? I see no option to do so after right clicking the respective file.


Can I move the minimap to the main screen?

It took like forever to figure out where I can find the minimap in MK8, and now that I found it it's still really annoying always having to look down when I want to know where the other characters are.  Is there a way to Move the Minimap from the gamepad to the Main screen? And if yes: How can I achieve this?


How do I change my Gmail profile picture?

I opened a Gmail account and uploaded my profile picture. Later I decide to change the picture, but I cannot find how to do it after the Gmail UI has been updated.   How can I change my picture?


If $\sum\limits_nz_n$ converges and $|\arg(z_n)|\leq\theta<\frac{\pi}{2}$ for every $n$ then $\sum\limits_nz_n$ converges absolutely

Prove that if $\sum\limits_{n=1}^\infty z_n$ converges and there exists $\theta\in\mathbb{R}$ such that $|\arg(z_n)|\leq\theta<\frac{\pi}{2}$ for all $n\in\mathbb{Z^+}$, then it converges absolutely.  I tried invoking the convergence of $(z_n)$ to $0$, but couldn't find a second step or a route. Could someone give me some hints please?  Added later:  For all $n\in\mathbb{Z^+},z_n=\Re z_n+i\Im z_n$. Since  $\sum\limits_{n=1}^\infty z_n$ converges  $\sum\limits_{n=1}^\infty \Re z_n$ converges. But for all $n\in\mathbb{Z^+}$, $$\Re z_n=|z_n|\cos(\arg z_n)\geq|z_n|\cos\theta\geq0.$$ Now invoking the comparison test the convergence of $\sum\limits_{n=1}^\infty |z_n|\cos\theta$ is immediate. Hence $\sum\limits_{n=1}^\infty |z_n|$ converges, i.e. $\sum\limits_{n=1}^\infty z_n$ converges absolutely.


Dunn.test - interpretation p-value and Ho rejection

I am using the Dunn test (the package Dunn.test in R) as a post-hoc test to my Kruskal Wallis analysis. My alpha value is 0.05, so I would reject the Ho for p - values <= 0.05.   When printing my results, R prints the note:      alpha = 0.05   Reject Ho if p <= alpha/2   Does anybody happen to know why R advises me that I should reject Ho if the p-value is 0.025 even at a set alpha value of 0.05? (For clarity: why is R using this particular decision rule of alpha/2 instead of just alpha?)  My guess would be that it has something to do with testing one- or two sided. I couldn't find if the default of Dunn.test and therewith the given results is for a one or two sided approach.


Is it always true that $p_1p_2p_3\cdots p_i > p_{i+1}^2$ where $p_i$ are the prime numbers listed in increasing order and $i>3$?   I was wondering if this is true because it would seem to depend on the prime gap between $p_{i}$ and $p_{i+1}$. Testing a few examples seems like it is likely to be true.


A creative online short story written about artificial intelligence

As best as I can remember the story is about a female protagonist who has grown extremely discontent with her (now) immortal life. She was one of the original programmers who helped create this omnipotent computer which once built, became self-aware, and made “the change”. Where everyone in reality became virtual gods basically. There was no longer any scarcity, you can think anything into existence, have almost anything you want as long as it doesn’t go against the set rules of the computer. An example of something not allowed is suicide.  As our main protagonist is always trying to push the logical boundaries of what can be done, she creates a new sport. This is essentially death games where any challenger can enter into the world of your creation and battle through whatever maze of traps and challenges to win a prize.       Eventually she finds the original creator of the computer, and they realize that the computer has the ability to reverse the original event that made humanity what they are today, so long as the computer deems it is for the greater good of mankind. Through a series of logical loops, they are able to convince it that humanity needs to basically control their own destiny again.


Upgrading from OS X 10.10 Yosemite Developer Preview

I did sign up for Apple's Public Beta program but was too late and missed out on the Developer Preview as they were offered to only the first one million sign-ups. Anyway, today I just managed to grab a copy off a torrent site and it's now lying on my computer.  Now before I proceed to install it, I would like to know what happens to me when Apple releases future beta updates. Will I be able to just update my OS as a regular copy or will I again need to search for and download an updated copy off the torrent? What happens when Apple finally releases the official copy come fall? Will I be able to just hit the Software Update option in the Apple menu and get it done or will I have to download the whole shebang all over again?  P.S. I understand there are risks involved with installing Dev Previews and am not worried about them. Thanks.


I am tiling my bathroom floor and don't soon have a full day to dedicate to the job. Is it ok to lay down a few tiles each day and come back to the job when I have time? I would only lay mortar for the tiles I have time to lay each day.    My concern is that the mortar wouldn't properly "join" to the previously laid sections of tile and cause an inferior result, but I'm not really basing this concern on any facts. That is what I'm hoping to learn with this question.


Applying Two Different Materials on 2 Sides of a Face

I have to apply two different materials on the two different sides of a face. I know how to use double sided materials (with two different pricipled bsdf shaders and a geometry node connected to a mix node), but in this case I will have a single material behaving differently on the 2 sides. I need 2 different materials on the two sides of the face to import the model in substance painter. Is there any chance to apply the two different materials on the two sides or the only chance is to produce a double sided single material?


Proof: $\cos^p (\theta) \le \cos(p\theta)$

I came across this problem when I was at a book store inside of a book made to prepare Berkeley graduates to pass a mandatory exam. I wanted to buy the book, but, alas, I didn't have the money (forty bucks is a lot of money when you don't have a job). So I took my phone out and started taking as many pictures as I could. Unfortunately, I didn't take any pictures of the solutions!  Enough backstory. Time for math. The problem is as follows:  Prove that $\cos^p( \theta) \le \cos(p \theta)$ if $0\le\theta\le\frac\pi2$ and $0\le p\le 1$.  I tried using the series expansion for cosine, but that seemed to be a dead end. Then I tried using Euler's theorem, but I got stuck. Then I got distracted and started to think about other cosine identities. For example, $$\cos\left(\frac\theta2\right)=\pm\sqrt{\frac{1+\cos(\theta)}{2}}.$$ Then what is $\cos(\frac\theta3)$ equal to? I tried to figure it out then I realized that I needed to find the root of a cubic polynomial. Then I realized that I'm better at staying focused than finding the roots of cubic polynomials.  Anyways, a proof would be nice here. I really appreciate any hints or answers. I apologize for my digressions!


Prioritize one Wi-Fi network over another

When two Wi-Fi networks, both of which I've chosen to connect to automatically, are in range at the same time, is there any way to tell Ubuntu to prefer one network over the other?


I've tried looking at posts on this issue but am still having some trouble with this error in my code. So in the fourth line, I create an instance variable called SongDatabase to access the SongDatabase class. But when I get down to the line, SongDatabase.addNewSong(); under case 1, I get a java.lang.NullPointerException: null error.  Interface class:  public class Interface  {     Scanner console = new Scanner(System.in);     private SongDatabase SongDatabase;      public static void main(String[] args) {         Interface intFace = new Interface();         intFace.run();     }      private void run() {         switch (userInput) {         case 1:              SongDatabase.addNewSong();             break;         case 2:             SongDatabase.removeSong();             break;         case 3:             SongDatabase.sortSongs();             break;         default:             System.out.println("Please enter a valid number.");             break;      } }   SongDatabase class:  public class SongDatabase {     Scanner console = new Scanner(System.in);       private Song song1, song2, song3, song4;  public void addNewSong() {                 if (song1 == null) {             song1 = getFromUser();         }         else if (song2 == null) {             song2 = getFromUser();         }             else if (song3 == null) {             song3 = getFromUser();         }         else if (song4 == null) {             song4 = getFromUser();         }         else {         System.out.println("The database is currently full. Please delete a song before adding a new one.");        }         }   I've stepped through the debugger and I know that the instance variable, SongDatabase = null, which is probably causing the error? I previously had a line   SongDatabase SongDatabase = new SongDatabase(); SongDatabase.addNewSong();   instead, but I realised this was creating a new SongDatabase object everytime and wiping what I had stored in there so I had to change it. I'd really appreciate a solution because I have no clue, thanks!


I use a Canon 70D with a Canon EF-S 17-55mm f/2.8 IS USM lens, and it gives a nice, very beautiful video. But, I think it is time to jump in to the full frame world.  Can I use my lens with Canon 6D?


Dupehammer creates and deletes a comment, causing notifications to go out

is a good system. But when a gold badge holder closes a question, a comment still gets created on the voter's behalf, even though it will be immediately deleted by the system due to the question being closed as a duplicate. This is contrary to what normally happens when a moderator closes a question - no comment is ever created or deleted.  This is problematic because the comment's creation (even though it gets deleted in the same instant) still causes notifications to be sent out:   The owner of the question receives an inbox notification telling them that there is a new comment on their post, which doesn't actually exist anymore. Anyone viewing the question at the time  that there is a new comment on the question, only to have nothing new at all load when they click to load the new comments.   I propose that all binding close votes refrain from leaving a comment, not only those cast by diamond moderators.


I came up with a Complex "Proof" idly at work today that seemed to be rather simple, but proved counterintuitive on paper. Year 12 Student looking into pure mathematics, so all feedback is cool and interesting.  $-i = -1 \times {(-1)}^{1/2}$  $-i = i^2 \times {(-1)}^{1/2}$  $-i = {(i^4)}^{1/2} \times {(-1)}^{1/2}$  Since:       $a^n \times b^n = {(ab)}^n$  $-i = (i^4 \times -1)^{1/2}$  And: $i^4 = 1$  $-i = {(-1)}^{1/2}$  $-i = i$  $\therefore -1 = 1$  Awesome.  I expect to use stackexchange religiously in the upcoming years, so I'll debut with this dumb loophole and hopefully come back again with some serious dilemmas.


Bash : Elegant way for : case $1 in "parameter1" or "parameter2"

Here is my Bash script.  Assuming that : 1) go.sh is the script to execute 2) the user will launch the script this way   # ./go.sh -v file1.txt file2.txt   or   # ./go.sh --verbose file1.txt file2.txt   3) I would like to have a more elegant way to write this :  #!/bin/bash Verbose_Mode=0  until [ "$#" == "0" ]; do    case $1 in      "-v" or "--verbose")       Verbose_Mode=1       ;;   This will result in a syntax error because of :"-v" or "--verbose".   My question : How can I properly write (if possible) the code :   #!/bin/bash Verbose_Mode=0  until [ "$#" == "0" ]; do    case $1 in    "-v")    Verbose_Mode=1    ;;    --verbose")    Verbose_Mode=1    ;;    esac   Thanks in advance for answers.


Fix NullpointException inside Async Try Catch (doInBackground()

I am having this error when running the below code trying to parse the website using JSoup.  ERROR  java.lang.RuntimeException: An error occurred while executing doInBackground()  Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'org.jsoup.select.Elements org.jsoup.nodes.Element.getElementsByTag(java.lang.String)' on a null object reference   The website doesn't have table with the specified id (getElementById('ctl00_ContentPlaceHolder1'). How to fix this exception where the table isn't present?  CODE  @Override protected Void doInBackground(Void... voids) {     try {         Document evalPage = Jsoup.connect("http://site.example.com")                 .cookies(loginCookies)                 .timeout(30 * 1000)                 .execute().parse();         //TODO FIX THE NO TABLE REFERENCE          table = llPage.getElementById("ctl00_ContentPlaceHolder1").getElementsByTag("table").get(2);      } catch (IOException ex) {         ex.printStackTrace();         parsingSuccessful = false;     }     return null; }


Is there a way to solve for $x$ for $\tan x=2x$?  My cousin asked me about this and I wondering if there was some sort of trig identity I had to know.


Elsarticle frontmatter corresponding author

I believe I have followed the template exactly but as this following MWE shows I am getting an asterisk on both authors and not just the corresponding author. Do I have something in the wrong order somewhere?  \documentclass[preprint,12pt]{elsarticle}  \begin{document}  \begin{frontmatter}  \title{Title}  \author{Author One\corref{cor1}\fnref{fn1}} \ead{email@uni.edu} \cortext[cor1]{Corresponding author} \fntext[fn1]{Student}  \author{Author Two\fnref{fn2}} \ead{email2@uni.edu} \fntext[fn2]{Lecturer}  \address{Address Here}  \begin{abstract} Abstract abstract abstract \end{abstract}  \end{frontmatter}  \section{Section1} Start typing...  \end{document}   Thanks


Lately I have been listening to a local morning show, the sports analyst for this show, when referring to "Runs Batted In", always says (Rs - B - I) instead of (R - B - Is). I shudder every time I hear this because it just doesn't sound correct. What is the proper way to say this and why?


Mongodb suddenly fails with message "No space left on device"

Mongodb fails with message "No space left on device". Mongo log:  $ sudo tail -n 5 ./mongodb/mongod.log 2016-11-10T07:19:46.821-0700 E STORAGE  [initandlisten] WiredTiger (28) [1478787586:821178][9468:0x7f54e7014d40], file:WiredTiger.wt, WT_SESSION.checkpoint: /var/lib/mongo/WiredTiger.turtle.set: handle-open: open: No space left on device 2016-11-10T07:19:46.821-0700 E STORAGE  [initandlisten] WiredTiger (28) [1478787586:821251][9468:0x7f54e7014d40], txn-recover: Recovery failed: No space left on device 2016-11-10T07:19:46.830-0700 I -        [initandlisten] Assertion: 28595:28: No space left on device 2016-11-10T07:19:46.830-0700 I STORAGE  [initandlisten] exception in initAndListen: 28595 28: No space left on device, terminating 2016-11-10T07:19:46.830-0700 I CONTROL  [initandlisten] dbexit:  rc: 100   but I have enough space and inodes:  $ df Filesystem         1K-blocks       Used Available Use% Mounted on /dev/ploop35670p1 2113654704 1530326948 497220988  76% / none                 8388608          4   8388604   1% /dev none                 8388608        160   8388448   1% /dev/shm $ df -i Filesystem           Inodes   IUsed     IFree IUse% Mounted on /dev/ploop35670p1 134217728 1575620 132642108    2% / none                2097152     155   2096997    1% /dev none                2097152      51   2097101    1% /dev/shm   OS version:  $rpm -qa | grep centos-release centos-release-6-8.el6.centos.12.3.x86_64   Mongo version:  $ mongod --version db version v3.2.10 git version: 79d9b3ab5ce20f51c272b4411202710a082d0317 OpenSSL version: OpenSSL 1.0.1e-fips 11 Feb 2013 allocator: tcmalloc modules: none build environment:     distmod: rhel62     distarch: x86_64     target_arch: x86_64   How can I find source of the problem?


Where does the ground wire go in a 3-prong dryer cord configuration?

We moved to a new place where the dryer connection is 3-prong instead of 4-prong. The dryer was originally 4-prong, so we bought a 3-prong cord and installed it. It works fine, except I am not entirely sure if I installed the ground wire correctly.   Originally, there was a green wire on the cord itself, and that was connected to the screw on the top of the first picture. This is, I assume, used to ground the case and prevent shocks when touching the exterior of the dryer.  Now with the 3-pronged plug, there is no ground wire on the cord. So where does the existing green wire in the case go? Do I leave it where it originally was like in the first picture or do I connect it to the central terminal like in the second picture?      There's no bonding strap running from the case to any terminal. I can't tell where the green wire is connected to.


What is it called or the term for when I use the word "You" to mean "Everyone"?

Such as when I say "Well, you can't just walk into a bar and yell fire" meaning anyone can't walk into a bar and yell fire.


Installing Xubuntu. Should I use repositories or install directly from the xubuntu disc image?

I am considering two options for installing Xubuntu 14.04.1 on my PC. I can install Ubuntu using  disc image, and then use the repositories to install the Xubuntu desktop.  The other option is to install Xubuntu using  disc image directly.  What are the differences between these two paths to getting the Xubuntu desktop on my PC? What are the pros and cons?


Is it correct to use either "to+infinitive" or "for+ing" in sentences like the following:     He has all the tools to become/for becoming a great actor.   I think "for +ing" sounds better in these types of sentences because we are talking about the purpose of a thing, the "tools" (the "tools" will help him become a great actor). However, I did a google search and found lots of examples with the "to+infinitive" structure, and, honestly, it doesn't sound bad either. So, is there any difference between using one or the other structure in sentences like the example? If there's no difference, could you please explain why?  By the way, I wrote "to+infinitive vs. for+ing to express purpose" as the title of this question. Would it be correct if I wrote "to+infinitive vs. for+ing for expressing purpose." If yes, why? If no, why not?


I'm a PhD student in literature who is nearly half way through my third year.   Recently (last month or two) I feel like I've lost all motivation to work on my thesis. Instead of treating it like a normal 9-5 workday I now go in late most days and procrastinate for a few hours before starting any actual work.   I'm not up to where I wanted to be in terms of chapter drafts at this stage of my program, but instead of this motivating me to work harder I just feel disheartened and like I will never catch up so why try. These defeatist thoughts make me feel even less like working so i end up in a vicious spiral of not working, guilt about not working, no motivation to work, more not working.  I feel overwhelmed by the amount of material I feel I still need to read to be 'across' my field and don't have a good sense of how im going to tie my various chapters into an coherent piece of work connected by an overarching argument and theoretical framework.   I have been managing an anxiety disorder throughout my PhD, and have in the past suffered from depression. I struggle to know if these feelings mean my overall mental health is deteriorating and that's what's causing the negative feelings about the PhD, or if it is the fact that I spend most of my time doing/thinking about PhD and so if I feel good about it then I feel good most of the time, and if I feel the research is going bad I feel bad most of the time. I've been sleeping to avoid going to the office and feel down about the thesis but this doesn't carry over to other aspects of my life - which leads me to think it's more phd-caused than mental health but who knows.   My supervisor is unaware of the underlying mental health issues. I struggled early on in first year which lead to me telling her I felt overwhelmed and she instructed me to take a week off, but I didn't outright disclose the anxiety. I've tried to flag recently with my supervisor that I feel a bit lost and behind, but she didn't seem overly concerned and I think I downplayed the extent to which this is impacting on my day to day work on the thesis. I wonder if I need to be more overt about how much I'm struggling, or disclose the underlying mental health issues. We have a very good r/ship which often feels more like a friendship than a supervision - which has it's upsides as well as downsides when it comes to something like this as I don't want to let her down or for her to be disappointed in me by disclosing how much work I'm not doing, but also don't want to ruin the friendly vibe by getting all serious with how I'm feeling re: thesis. I'm worried that even though she seems happy with where I'm at draft wise, she thinks I've read much more than I have because she doesn't know how much time I'm spending avoiding the thesis.   Part of me feels I should just 'get on with it' and if it is mental health as the underlying cause this is not something my supervisor should have to manage anyway so why bring it up. Another part of me feels I should be more honest with her about how much I feel I'm struggling with the thesis and not worry about seeming needy or incapable.   I feel like the time toward completion draws ever closer and yet the amount of work I need to do to finish doesn't progress at the same rate. I feel like I don't work hard enough at the moment to finish on time, and this feels both terrifying and paralyzing. I've read lots of blogs about procrastination tips and such but struggle to put them into action. I've also read lost about mid phd slump/doldrums so logically know this isn't uncommon, but at the same time I've lost some of self-confidence to think I'll be able get through this phase like others have.


Why a exception is not raised? If enum size is less than 100 Bytes

The size of the union is 95 bytes, why if I try to access to 102 postion at a, a exception is not raised?, or Am I just overwriting another memory location?     #include<stdio.h>    union u{       char a[95];       int b;       char *c;     };     union u u1;    int main()    {        u1.a[102] = 'b';        printf("%c",u1.a[102]);       return 0;     }


Installing Ubuntu on 24GB mSSD Hardware Acceleration Cache

I bought an  laptop with a 24GB mSSD customization. I want to install Ubuntu in a dual boot setup alongside the existing Windows 8 OS.  I've disabled Secure Boot and Intel Smart Response Technology, but when I try to install Ubuntu, I'm unable to identify any 24GB partition into which I can install / (the root partition).  Any kind of help would be highly appreciated.


How can a regression be significant yet both predictors be non-significant?

I know this question has been asked in a slightly different form . But my question differs and because of the forum rules I can't post on that thread. I have 2 independent variables, n=32, highly significant multiple regression, but only the intercept/constant has a significant p value.  Also, I've tested for multicollinearity, it's not in the readout from R below, but the variance inflation factor for the 2 dependent variables is 2.02. Durbin-Watson, added variable plot, P-P plot, standardized residuals plot, and cook's distance are all normal. Here's the R readout - please let me know what you think.    SO: This topic is relevantly different since; what I'm searching for and still haven't found, is an actual explanation for what having a significant regression and no significant predictors means. How can this finding, if accurate, be explained? @Glen_b, I have seen that part of Jeromy's post (see my 2nd comment above) but how would I explain that in prose? Would it be accurate to say that the variables, together, have an effect on the outcome - but that their effects cannot be isolated from each other?


Rotating a button in Unity UI by -180 on the Y and it stops working

If I rotate my button by -180 on the Y axis I can't even click on it. If for example I rotate it 180 on the Z axis everything is fine. Why does this happen and how can I fix it ?


How to stop being asked to unlock "Default Keyring" on logging in?

I am using Ubuntu 17.10 and Gnome 3.   Every time I login, I am immediately prompted with:     Enter password to unlock An application wants to access the keyring Default keyring, but it is locked.      How do I prevent this?   What is application is trying to access this keyring?  Why is it not unlocked? I am already logged in and it is locked with the same password...   I have tried every answer in [this question][2] but none of them work. That question is about "Seahorse" which I am not using.  Furthermore, in order of answers to    Answer 1 does not work because it asks me to go to Open Applications -> Accessories -> Password and Encryption Keys  but I do not have Password and encryption keys Answer 2 does not work because: It is super old (5 Ubuntu versions ago) and I can't access the Password and Keyring  Answer 3 does not work because: It is even older and the interface has changed Answer 4 does not work because: system / Preferences / Passwords and Encryption Keys does not exist for me   -Answer 5 does not work because it mentions Open Applications > Accessories > Passwords and Encryption Keys and this menu does not exist on my system.  etc.   and buried in the comments is this:     The solution was to go inside the ~/.local/share/keyrings folder and write login in the default file. Then I deleted the old Default_keyring, and rebooted, and it worked   However, trying that just creates 2 prompts.  One to create a new password / keyring, and then another to unlock it:    So, does anybody have any ideas for the three questions listed above, or mainly just how to fix this on modern Ubuntu (17) and Gnome 3?


Buck Converter Control Scheme- Why isn't just a comparator not enough?

I am supposed to come up with some control schemes for the converter before understanding the standard PWM control scheme.   Isn't it just enough if the output of the converter is compared with a fixed reference voltage to drive the output to required voltage level? Although I'm not sure there is a lot more to it, this seems to work pretty well.   I've tried simulating this circuit with L,C and R values from an example.  Schematic:    The required output voltage is 6V. S2 is a voltage controlled switch, controlled by the output of comparator.    V2(green) is the output of comparator and V1(red) is the output of buck converter.


Return non-zero exit status if a child processes fails

I have a docker build script which builds a series of libraries and runs test suits. In order to make my build script run faster on a many core server, I changed put the sequential order of commands (being passed to RUN to a bash invocation of several parallel commands:  RUN /bin/bash -c -e '\     cmd1 arg1 & \     cmd2 & \     cmd3 arg1 arg2=foo arg3 & \     wait'   This worked file when there was no error. Then I realized even if one of child processes return a non-zero exit status, the whole bash command returns 0 and docker continues to build... How can I make the bash call to return 0 iff all its children return 0 ?


I changed the SSH port on my server, but I then forgot to open a hole in the firewall for that port specifically. Now I cannot SSH into my server anymore. Is there any way around this?  Thanks


I've seen a few sources that mention the speed of an electron in a hydrogen atom is 1/137 the speed of light.  article also mentions what looks like a correlation between atomic number and the numerator meaning gold's electron speed is 79/137 the speed of light.  Does this imply that the highest element possible would be element 137 (or more likely 136)? Not referring to anything stable, just what is possible with physics (and hadrons).


existence of a normal subgroup with certain properties

Suppose $B$ is a group, $A\leq B$ with $[B : A] = b < \infty$ (here $[B : A]$ is the cardinality of $B/A := \{bA : b \in B\}$). Show that there is a normal subgroup $C\unlhd B$ with $[B : C] \leq b!$ and $C\leq A.$  I know various theorems that might help with this. For example, I know Cayley's theorem, which states that if $B$ is a finite group, then $B$ is isomorphic to a subgroup of $S_B,$ the set of invertible functions from $B$ to $B$. Also, I know that if $B$ is  a finite group, and $p$ is a prime dividing $|B|,$ then $B$ has an element of order $p$. I also know that if $B$ is a finite group and $A\leq B$ has index $[B : A] = p,$ where $p$ is the smallest prime dividing $|B|,$ then $A\unlhd B.$ However, I'm not sure which facts to use to find $C$. With $b!$, it seems that some permutations may be involved. It also doesn't seem very useful to come up with a contradiction.


How do I prevent less from clearing the screen on exit?

I often pipe commands to less in order to read through the output (e.g. compiler errors).  MyCommand | less   This is great because it makes trawling through large amounts of output easy, but when I exit less the output is gone. How can I make the output still visible after quitting less?  This question differs from  because that question relates to output to a text file via tee, which, as far as I know, doesn't provide a facility to split output between less and stdout.


How to automatically fetch missing dependencies when installing software from .deb?

I'm trying to install  on my Ubuntu box (11.04). The website has a Ubuntu .deb available for download (for 10.10 and 10.04 so I chose 10.10).   However,   sudo dpkg -i mysql-workbench-gpl-5.2.34-1ubu1010-amd64.deb   yields:  (Reading database ... 194069 files and directories currently installed.) Preparing to replace mysql-workbench-gpl 5.2.34-1ubu1010 (using mysql-workbench-gpl-5.2.34-1ubu1010-amd64.deb) ... Unpacking replacement mysql-workbench-gpl ... dpkg: dependency problems prevent configuration of mysql-workbench-gpl:  mysql-workbench-gpl depends on libctemplate0; however:   Package libctemplate0 is not installed.  mysql-workbench-gpl depends on libpython2.6 (>= 2.6); however:   Package libpython2.6 is not installed.  mysql-workbench-gpl depends on libzip1 (>= 0.8); however:   Package libzip1 is not installed.  mysql-workbench-gpl depends on python-paramiko; however:   Package python-paramiko is not installed.  mysql-workbench-gpl depends on python-pysqlite2; however:   Package python-pysqlite2 is not installed. dpkg: error processing mysql-workbench-gpl (--install):  dependency problems - leaving unconfigured Processing triggers for bamfdaemon ... Rebuilding /usr/share/applications/bamf.index... Processing triggers for desktop-file-utils ... Processing triggers for python-gmenu ... Rebuilding /usr/share/applications/desktop.en_US.utf8.cache... Processing triggers for python-support ... Errors were encountered while processing:  mysql-workbench-gpl   My question is, is there a way to tell dpkg to automatically fetch missing dependencies, or do I need to manually apt-get install missing packages like libctemplate0 and  libpython2.6?   (Or alternatively, is there some other way to get MySQL Workbench easily up & running?)


Finding the process that is using a certain port in Linux

I'd like to be able to find out which process is currently using a certain port in Linux. Is there any way to do this?


Let, $$S_n = \sum_{1\leq j<k+j\leq n}^{} 1/k$$  In the book concrete mathematics, The next line shows  that,  $$S_n = \sum_{k=1}^n \sum_{j=1}^{n-k} 1/k$$  I am getting very hard times understanding how $1\leq j<k+j\leq n$ implies $1\leq k\leq n$ and $1\leq j\leq n-k$  How is it done? Can you suggest any resource that can help me manipulating inequalities?


I'm at my wit's end please help me. I have done all the things I needed to do with the controller and it still won't pick up. It does charge it but won't let me do anything with the PS4 even when I put it in safe mode.


If I'm using kit lens on a DX body will I get sharper image if using tripod for exposure time of 1/90sec or less ?


Is it possible in C# to inherit a subclass from a subclass?

I’m studying OOP at the moment, and I’ve got this thesis. Because I know that inheriting a subclass from a superclass be like: class superClass : subClass{ } but I’m curious if this is an acceptable form: class superClass : subClass1 : subclass2.  In a nutshell, I want to inherit a subclass from another one. Because what if I get into a problem like there is a subclass and it is inherited from a superclass because they have common data.  Thats fine right?  But here is the catch: What if I need another subclass, which has common data with both of the first subclass and the super or main class?


How to open apps in Ubuntu 12.04 to read documents, play music and video, surf the net and reading emails?


When I try any theme other than Ambiance or Equinox buttons (only when maximized)are from these two themes. I can't change them to be from my current theme :/ Is there any solution?


What is a word for purposely trying to avoid answering a question?

Is there a verb for someone trying to avoid the question at hand by digressing. Or to mess up the answer so as to create confusion? Or to give a vague answer?  (At the back of my mind, there is a word that is something like 'subfugate' - which is not an actual word I realised - but something similiar or along those letters? Or I could be plain mistaken)


Is there a non written rule to which person to use in the PhD thesis, 5 years of using "We" in the papers have brought me to the innate necessity to do it every time I describe something.  Recently, though, one of my lab-mates told me that I should use I, since it is your work, if the thesis were co-written, then it would be a different story.  Is there any standard in your universities, or do you have any preferred practice.


Let $f$ be a continuous function on [0,1].  Evaluate  $$\lim_{n\to \infty}  \int_0^1 x^nf(x)dx$$  My approach :  Consider $\int x^nf(x)dx = \frac{f(x)x^{n+1}}{n+1} - \frac{1}{n+1}\int x^{n+1}f(x)dx$ by using integration by parts.  then applying limit with $n\to \infty$ we get  $\int x^nf(x)dx = 0$, regardless of the limits of integral.  Is this approach correct?


Positive integers $a$ and $b$ are such that $ab+1$ is a factor of $a^2+b^2$. Prove that $\frac{a^2+b^2}{ab+1}$ is a perfect square.

IMO 1988 question No. 6  I have a confusion in the question.The question is as follows:     $a$ and $b$ are positive integers and $ab+1$ is a factor of $a^2+b^2$. Prove that $\displaystyle\frac{a^2+b^2}{ab+1}$ is a perfect square.   My confusion: According to me, $a$ and $b$ have only one value ie $a=b=1$. What are the other possible values of $a$ and $b$?


How to insert name of a cell into another cell?

Column F is a list of constants. Each cell is named. I want to insert the name of each cell in Column F into an adjacent cell in Column E. For example F9 is named "FeetPerMeter" and has a value of 3.28084. I want the value of E9 to be the text string  "FeetPerMeter".


Can a ball be decomposed into a finite number of point sets and reassembled into two balls identical to the original?  What is the true nature of this paradox ? I don't really understand this ?


What's the purpose of this bulky cylindrical part near the plug end of a laptop charger cord?

I want to fix my laptop charger cord, I used a multimeter to check the voltage and it gives me less than one volt. It feels very flexible near the plug, but I don't know if I can cut before or after the part marked in red. What is this part used for? Can I remove the red part?


PDF of unfair coin tosses with a set of differently biased coins

Let's say that I have a bag of unfair coins. Each coin $\mathit{i=1...N}$ has a probability $\mathit{p_i}$ of giving heads when tossed. If I toss each of my coins once and count the number of heads, what distribution (and parameters) will describe the number of heads I get? I know that if I used the same coin $\mathit{i}=I$ the probability mass function would be a binomial distribution $Pr(k;n,p_I) = \frac{n!}{k!(n-k)!}p_I^k(1-p)^{n-k}$ where $\mathit{n}$ describes the number of times I tossed the coin. In this case however I have $\mathit{n}$ different coins with $\mathit{p_1, p_2, ..., p_n}$ probability of heads tossed one time each.


$\sqrt {-3}$ multiplied by $\sqrt{-3}$ is $-3$. But this can also be written as $\sqrt {-3} \cdot \sqrt{-3} = \sqrt {(-3).(-3)}= \sqrt{9} =3$ So my question is why is this not possible?


Camera track to constraint in the game engine

I have tracked camera to track a ball. When I move the ball manually, the camera tracks it. But when I apply motion using w,a,s,d keys to move it top, left,down and right, the camera stops tracking the ball. Why is this happening?


How can I make a subfolder that looks and behaves like Documents/Music/etc?

The home folder starts with default folders (mostly XDG base directories) like ~/Documents and ~/Music. These are decorated as follows:   custom folder icon (not an emblem) custom icon matches the style of the regular folder icon Nautilus bookmark in a distinct section (separate from other bookmarks) custom bookmark icon   I have created a non-XDG folder called ~/Work. How can I decorate it with all four features listed above?


I am new in python programming for geospatial development. I want to create an app to allow users to click on a shapefile to get the data associated with that clicked point.   Which python libraries can I use?   and another suggestions to start in python programming for geospatial development?


I am new to Java. I was reading someone's solution to a question and I encountered this:          int[] ps = new int[N];         for (int i = 0; i < N; i++)             ps[i] = input.nextInt();          int[] counts = new int[1005];         for (int p : ps)             counts[p]++;   What do the last two lines do?


Stuck on Google Verification after performing a hard reset

I have Oplus phone with 5.1 Lillipop that stuck in google verification. Its says that I need to enter my previous gmail account to continue, but i don't have any access of it. I already forgot how I create that account. I have searched on google about this but I found nothing.


I have created an HTML page with modified from a template I got.... I want to send as a HTML based newsletter in Outlook 2016.  However the guides I see as "insert as text" do not apply to Outlook 2016 as there is no dropdown for inserting files for that in the 2016 version.  I am wondering how I go about being able to send this HTML email?


Lack of transparency in beamer default theme

I'm using the default LaTeX beamer theme. Unfortunately, for some reason, I don't get transparency anymore. The behaviour is the same across pdflatex, xelatex and lualatex.  Rendered:    MWE (requires an arbitrary image file):  \documentclass[compress,xcolor={usenames,dvipsnames,table},12pt]{beamer}  \title{Title} \author{Author} \date{September 14th, 2018}  \setbeamertemplate{background}{%   \includegraphics[width=\paperwidth,height=\paperheight]{background.jpg} }   \begin{document}    \begin{frame}     \titlepage   \end{frame}  \end{document}


I'm trying to copy some certificates onto my server using scp.  $ scp ./cert.* sshuser@192.168.0.42:/tmp/  cert.crt     100% 2386     0.1KB/s   00:18 packet_write_wait: Connection to 192.168.0.42 port 22: Broken pipe lost connection   The first file is written to the server, but not completely as the hashsum does not match with the original file.  This happens every time I try to scp these files (crt, key and p12).  Tested with Ubuntu 16.10 (OpenSSH_7.3p1 Ubuntu-1, OpenSSL 1.0.2g  1 Mar 2016) and with Windows 10 (WinSCP 5.9.4). Both fail copying the files.  It may be worth mentioning that I'm connected to an OpenVPN server, in order to reach the target server (192.168.0.42) - but that shouldn't be an issue.  Why does the pipe break and how can I successfully scp the files onto the server?  edit: This, as suggested in the comments, most likely has to do with the MTU - however, I'm not quite sure how to fix this issue yet.


Minimum distance between the curves $f(x) =e^x$ and $g(x) =\ln x$

What is the minimum distance between the curves $f(x) =e^x$ and $g(x) = \ln x$? I didn't understand how to solve the problem. Please help me.


As shown in the image below, I have a simple object that I want to shade smooth, so my final model won't be too heavy since I'm gonna repeat it thousands of times.  It appears that some faces are correctly shaded smooth, but others are not at all. When I saw this I immediately went to check if auto smooth was on and the angle setting here caused it, but this is not the case.  Everything looks normal in the lookdev and the solid shaded mode, also my topology shouldn't cause any of these problems.  Am I overlooking something very obvious here? I've been working with blender for hundreds of hours, but have no idea what is causing this. Any ideas?


Evalute $ \lim_{n \to +\infty} \sqrt{1 + \sqrt{2 + \sqrt{3 + \sqrt{...+\sqrt{n}}}}} $

My question is how to evalute this limit: $$ \lim_{n \to +\infty} \sqrt{1 + \sqrt{2 + \sqrt{3 + \sqrt{...+\sqrt{n}}}}} $$


When I executed the command:  curl https://piwik.openstreetmap.org/piwik.php?idsite=1   I received a warning that binary output can mess up my terminal, which, yes it did having ignored the warning, so my first question is why does binary output mess up the terminal?  I then passed the output to a text file as follows:  curl https://piwik.openstreetmap.org/piwik.php?idsite=1 > binaryFrom_Openstreetmap_php.txt   And this did not result in erroneous output, rather the verbose output in the terminal was:  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current                                  Dload  Upload   Total   Spent    Left  Speed 100    43  100    43    0     0     17      0  0:00:02  0:00:02 --:--:--    17   Now the second question is, having observed the following to be the content of the text file:  GIF89a  €        !ù    ,       D ;   How is this binary when there are more than two characters? Unless I've been misusing the word binary my entire life, I cant discount that possibility entirely.  And thirdly, when viewed in a text editor on a Linux OS the characters are different to what is displayed when this file is viewed in a Windows 10 OS, why?


Punctuation, compound sentence, Oxford, and

I've got myself confused with comma placement before the word 'and'.    I've read elsewhere on here that a comma should go before the word 'and' for compound sentences (this example was used, which I've borrowed, hope that's okay):  A cat can climb trees, and it can climb curtains.  [A cat can climb trees] + [A cat can climb curtains].  But how does this differ from a 'list', evoking the Oxford comma debate probably about using a comma in a list form, e.g.: a cat can climb trees, curtains and humans.  Why is the above feline example not also considered a 'list'.   Here's another example - is this a compound sentence or a list or both? I assume it's a compound sentence, but it could be considered to be listing actions that they intend to do.     EXAMPLE  We’re risk assessing every person on a case by case basis and we’re deciding what further treatment is required.    Have I got myself unnecessarily confused?!


Best principle for designing notification experience

I'm currently building a the base notification system for a startup I'm working at, and am having a hard time defining the line between being spammy and making 100% sure the user knows about something they should.   Of course the user will have options to change their preferences, but defaults are what most people will deal with and are important.   We will notify users in many ways, sms, email, web, and a facebook app notification.   I'm thinking following the idea of "Make 100% certain the user knows, but don't bother them beyond that" would lead to the best design. Meaning to send users   Currently I'm planning on sending essential notifications (we won't have any other notifications for a few months) via all channels: sms, email, facebook and web.    The nice thing I see about this is that wherever the user has technology, they'll get it right then and there.   With twitter, I enjoy getting a text and then clicking on my messages or mentions when I'm on the web.  Any feedback on this would be appreciated.


How to interpret the student t statistic in a sas proc univariate output

I ran a proc univariate on a SAS data set and one of the output results was:  Test           -Statistic-    -----p Value------ Student's t    t  73.93231    Pr > |t|    <.0001   How should I interpret this? Does it mean that the probability that an observation will be > 73.93 is very small (< .0001)


Does this basic cardinal inequality require the axiom of choice?

I know that in set theory it should be the case that if $\vert X\vert\geq \vert Y\vert$ and $\vert Z\vert\geq \vert W\vert$, then $$ \vert X^Z\vert\geq \vert Y^W\vert .$$ For this I want to map a function $f:W\to Y$ injectively to a function $g:Z\to X$. It seems natural that I construct the map $g$ from the conditions on $\vert X\vert\geq \vert Y\vert$ and $\vert Z\vert \geq \vert W\vert$, however I can not use the fact that $\vert Z\vert\geq \vert W\vert$ directly without the axiom of choice. My proof is as follows: Since $\vert Z\vert \geq \vert W\vert$, there exists a surjective function  $G:Z\to W$. Since $\vert X\vert \geq \vert Y\vert$, there exists an injective function $F:Y\to X$. Then the map $\Phi:Y^W\to X^Z$ is an injective function defined by $\Phi(f)=F\circ f \circ G$. However this proof requires that there exists such a surjective map, which I understood to not be necessarily the case if we don't assume the axiom of choice. My question is what would be a correct injective mapping from $Y^W$ to $X^Z$, since I'm pretty sure that the property I want to show is true without assuming the axiom of choice.


"Who(m) will it be?" vs. "Will it be he/him?"

The accepted (and highly upvoted) answer to the question in the question   states that the easiest way to find out whether to use who or whom is to try with he/him and see which fits. But that doesn’t seem to fit very well in this case:   Who will it be?  Whom will it be?    If I replace with he/him there, it becomes:   Will it be he?  Will it be him?    – and I don’t know which of these is right, either. Is it really true that you can always associate who with he and whom with him? Or does that not always work? And which out of 3 and 4 is correct?


Java variable setting (how does = work?)

Consider the following code:  public class Office {     int room;     Office(int room) {         this.room = room;     } }  class Test {   public static void F2(Office o1, Office o2) {       o2 = o1;       o2.room = 63;   }   public static void main(String[] args) {       Office labOffice = new Office(130);       Office commonOffice = new Office(275);       F2(labOffice, commonOffice);       System.out.println(labOffice.room + ", " + commonOffice.room);   } }   Inside method F2, after setting o2.room to 63, shouldn't both o1.room and o2.room become 63? Why does printing still give me 275 for commonOffice?


Apparent weight of an empty balloon vs apparent weight of a balloon filled with air

If the same sensitive spring balance weighs (in air) a balloon when empty (W1) and when filled with air (W2), which reading will be greater and why?


How should I update the link used for marking a question as duplicate?

I tried to search but couldn't find an answer to this. The problem seems to be very basic. I saw a question on SO and found that It's a duplicate of another question so decided to cast Close vote on it. While doing so I selected the reason as duplicate but I accidentally provided a wrong link. Now, when I click again, the dialog opens but there's no way to update the link. How should I do that?


Partition the drive in which ubuntu is installed

I got a laptop(64-bit) with ubuntu installed on it.It has 320GB hard disk,but only one drive is there of all 320gb in which ubuntu is installed.I want to partition this single drive on which ubuntu is installed, into 2 partitions so that i can install win8 also.  So i want to shrink the drive in which ubuntu is installed without formating it,so that i  can create another partition from it


Why are text articles on the web so thin?

I've recently noticed that articles on the web tend to be very thin with lots of whitespace to the left and right. Why is that?    Two examples:


How do I avoid lines at top and left borders of png files exported from Illustrator

When I export Illustrator artwork as a png file, I get a one pixel grey border at the top and left edges.  There is no background object, but I export (Save for Web and Devices) with matte white background and no transparency.  I also tried with a white background object, with it snapped to the artboard and also larger than the artboard by 10 pixels in each direction.  I still got the lines at the top and left of the exported image.  I also tried making a new file, with the artboard in pixel units, and selected the option to have objects snap to pixel grid, and then copying and pasting the artwork from the original file.  I still got the lines.


Term for things like "naughty step" where the step is not what is naughty

Can anyone remind me of the grammatical term for the apparent misapplication of an attributive adjective, as in the phrase "the naughty step" (where it is not the step itself that is naughty but the person consigned to it)?