discover software centre not working at all. Any alternative?

I have just installed Ubuntu 18.1 and I must say that 18.04 was better. So far the worst experience is with the Software Centre, Discover, which does not work. It takes an eternity to start and then to take action after clicking on anything. It is just a lump. Why is it there? There are other few utilities of Lubuntu that when clicked will won't do anything at all, like Compton. The difference is that the Software Centre is an important tool that we need to work efficiently, and now it is an absolute waste of space. In 18.04 it worked fine, why to change it? Is there any alternative to it? I might need to ditch Lubuntu from this computer. All other packages and applications work perfectly. It is only the Software Centre. I have Lubuntu installed in a dual boot computer. Lubuntu 18.1 is in a SSD and Lubuntu 18.04 is a spinning drive. It does not matter why I have to versions of the same in the same computer.  When Discovery is running the output from free is              total        used        free      shared  buff/cache   available Mem:        4029500     1548376      582100      318612     1899024    1911080 Swap:       2084860           0     2084860  The output from top shows plasma-discover using 100% of CPU most of the time even when the program is idle doing nothing (and 3.7% of RAM).


I a, getting the output as 10 9 9 10 for this program but I am not able to understand why swapping is not working.  Given below is the code:   public class Swap {  public static void main(String[] args) {     int a=9;     int b=10;      swap(a, b);      System.out.println(a);     System.out.println(b); }  public static void swap(int a ,int b){      int temp=0;     temp=a;     a=b;     b=temp;     System.out.println(a);     System.out.println(b);   }


How can I disable the automatic locking on idle mechanism in Windows 8? I have tried:   Disabling screen saver and screen saver "lock on resume" --> done Disable lock on wake in power options --> done   I still cannot find a solution - it seems to lock after some period of inactivity.  Edit:  This is NOT A DUPLICATE - the answer and question marked as duplicate are both unrelated to the question. The question is to disable auto-lock not to disable the screen before the password entry.


So why exactly is it that it's always recommended to use const as often as possible?  It seems to me that using const can be more of a pain than a help in C++.  But then again, I'm coming at this from the python perspective:  if you don't want something to be changed, don't change it.  So with that said, here are a few questions:   It seems like every time I mark something as const, I get an error and have to change some other function somewhere to be const too.  Then this causes me to have to change another function somewhere else.  Is this something that just gets easier with experience? Are the benefits of using const really enough to compensate for the trouble?  If you don't intend on changing an object, why not just not write code that doesn't change it?   I should note that at this point in time, I'm most focused on the benefits of using const for correctness and maintainability purposes, although it is also nice to have an idea of the performance implications.


Taking letters and numbers from different fonts

Can we mix fonts?  For example:   Letters from Palatino Numbers from Times New Roman Greek symbols from Fourier   Thanks in advance.


How can I limit the headphone max volume on OS X?

So I hurt my ears from excessively loud music last week at work. I'm well aware of the volume down key of course, but I tend to crank it up too much throughout the day without noticing it.    I need a limiter and it needs to be system-wide, since I listen to various other sound sources aside from iTunes. This isn't really an issue on my phone, since I can set a volume limit in the iOS settings.  Is there an equivalent built-in or third-party fix for OS X Lion?


Finding the inverse of linear transformations in $\mathbb{R}^3$

For each of the following linear transformations, find the inverse if it exists, or explain why there is no inverse.  (a) $T : \mathbb{R}^3 \to \mathbb{R}^3$ where $T(v)$ is the reflection of $v$ around the plane $x + 2y + 3z = 0$.  (b) $T : \mathbb{R}^3 \to\mathbb{R}^3$ where $T(v)$ is the projection of v along the vector $(1, 2, 3)$  (c) $T : \mathbb{R}^3 \to \mathbb{R}^3$ where $T(v) = Av$, $$A = \begin{pmatrix}         1 & 1 & b \\         0 & 1 & 1 \\         0 & 0 & 1 \\         \end{pmatrix},$$  and $b$ is a real number.  These are very confusing to me because I never learned linear transformations in depth. Any help would be appreciated.


Readyboost is a replacement for Pagefile? After activating Readyboost can we disable page file? Does the OS still use a Pagefile after activating Readyboost?


everybody.  I'm suppose to prove this without induction: Prove Without Induction: $\sum\limits_{k=2}^{n} \frac{1}{k(k-1)} = 1 - \frac{1}{n}$  I'm not sure how to do it. I tried a bit of algebraic manipulation, but I'm not sure how to do it.  It's suppose to be basic.  I did get a hint of factorizing $\frac{1}{k(k-1)}$ but that didn't get me anywhere.  A hint or any directions would be much appreciated!


Residue integral: $\int_{- \infty}^{+ \infty} \frac{e^{ax}}{1+e^x} dx$ with $0 \lt a \lt 1$.

I'm self studying complex analysis. I've encountered the following integral:  $$\int_{- \infty}^{+ \infty} \frac{e^{ax}}{1+e^x} dx \text{ with } a \in \mathbb{R},\  0 \lt a \lt 1. $$  I've done the substitution $e^x = y$. What kind of contour can I use in this case ?


What does $Pr(dx,dy)$ mean in this notation?

This is equation 2.10 from the book Elements of Statistical Learning:  $$ E[(Y-f(X))^2] = \int (y-f(X))^2Pr(dx,dy) $$  $X$ is a real valued random input vector and $Y$ is a real valued random output. $X$ and $Y$ have joint distribution $Pr(X,Y)$. $f(X)$ is an approximation of $Y$ for a given $X$.  I am confused by the $dx$ and $dy$ within $Pr$ in the integral. Does $Pr(dx,dy)$ mean the probability of $X$ and $Y$ lying in the $dx$ and $dy$ ranges, respectively?   Is the integral equivalent to $$ E[(Y-f(X))^2] = \int (y-f(X))^2 p(x,y) dx,dy $$ where $p(x,y)$ is the joint pdf of $X$ and $Y$?


Check convergence of $\sum_{k=2}^\infty \frac{1}{k^2-1}$

How can I check the convergence of $$\sum_{k=2}^\infty \frac{1}{k^2-1}$$ ? As it's almost the same as $$\sum_{k=2}^\infty \frac{1}{k^2}$$ which converges, it should converge, but I can't use a comparison between the two here, as $$\sum_{k=2}^\infty \frac{1}{k^2-1} \geq \sum_{k=2}^\infty \frac{1}{k^2}$$ so it wouldn't help. So how should I go about it?


How does the overhand chop ability work?

How does the fighter ability overhand chop from the Pathfinder Advanced Player's Guide work? Please give examples.  The reason I asked is that I have a player in my game that is using overhand chop. He has a 18 str, and he says he gets 12 to his damage instead of 8. I think he's exploiting a loop hole in the way it is written.  Is this interpretation correct?


How to temporarily disable sudo credentials timestamp timeout?

Let's say, I have the following bash script:  #!/bin/bash sudo command1 command2 sudo command3   I don't want to run command2 as root, so I won't run the script itself with sudo. Therefore, as soon as I execute the script, sudo command1 asks for my password. Unfortunately, command2 takes about 2 hours to complete. So the sudo credentials timestamp timed out and when the script reaches sudo command3, I'm prompted for the password again.  I don't want to permanently disable the sudo credentials timestamp timeout altogether as described in  for example. I just want to disable the timeout temporarily, effectively keep the credentials for this one bash session until it ends.


Capacitors:   Using direct current I apply a voltage, $~V_o~$, to a capacitor of capacitance $~C~$. It acquire a charge of $~Q_o~$. I remove the charging source and I connect both sides of the capacitor to another capacitor. The second capacitor is identical but initially uncharged. In all of this, I am using low resistance cables to make the connections. After a short time, I find that the charges have equalized between the two capacitors, and each has a charge equal to $~\frac{Q_o}{2}~$. Furthermore, I find that the voltage is equal to $~\frac{V_o}{2}~$.  I know that the energy stored a capacitor is $~\frac{CV^2}{2}~$. I also know that the first capacitor has an energy of $~\frac{CV_O}{2}~$, and the energy stored in the two capacitors after charge equalization is $$2~ \left(C ~\frac{\left(\frac{V_o}{2}\right)^2}{2}\right) = \frac{CV_o^2}{4}~.$$  Unless my calculations are wrong, half the energy disappeared.   Where did it go?


I think consensus is that we want StackExchange to be the go-to place for any question anyone may ever have, as long as this question is on-topic for the specific SE domain. People often mention that StackExchange should be the top result in Google for such questions, and that it's okay to ask a question on StackExchange even if that question was already answered elsewhere on the internet.  Meanwhile, we encourage people to vote on questions, partly based on the research effort. If the question clearly lacks research effort (in other words, the answer can be found with a simple Google search), a downvote is warranted.   Isn't this a bit conflicting, though? For instance, I think it is great to have the question  on Stackoverflow. It has over two thousand upvotes, which is great. However, when it was posted (in 2008) there were already numerous good articles about this on the internet, and the question can indicate a lack of research effort. By now, the question (and its answers) are top results in Google whenever you search for remedies against SQL injection.  Am I the only one who thinks that research effort is not a particularly good criterion for upvoting/downvoting a question? As I understand it, we should not tell users to *read the f***ing manual*; we want StackExchange to be the manual.   Can anyone explain me where my logic is wrong?


How to write a function (piecewise) with bracket outside?

How to write this Piecewise function using LaTeX?  I tried $ \begin{array}{cc}   \{ &      \begin{array}{cc}       0 & x\leq 0 \\       \frac{100-x}{100} & 0\leq x\leq 100 \\       0 & 100\leq x     \end{array} \end{array} $  but it didn't work perfectly, the bracket "{" looks small, see:


Why can't I run a batch command from my java program?

I'm trying to run a command from my java application. I get input from the user and run this line of code: Runtime.getRuntime().exec($userInput);. I've tried lots of simple commands, including "echo," "start chrome," and "rem." It seems that the only command that works is "cmd.exe," and I have no idea what that even does.  Commands such as "echo" generate this error:  java.io.IOException: Cannot run program "echo": CreateProcess error=2, The system cannot find the file specified             at java.lang.ProcessBuilder.start(Unknown Source)             at java.lang.Runtime.exec(Unknown Source)             at java.lang.Runtime.exec(Unknown Source)             at java.lang.Runtime.exec(Unknown Source)             at me.Draconwolver.Main.runCmd(Main.java:119)             at me.Draconwolver.Main.main(Main.java:34) Caused by: java.io.IOException: CreateProcess error=2, The system cannot find the file specified             at java.lang.ProcessImpl.create(Native Method)             at java.lang.ProcessImpl.<init>(Unknown Source)             at java.lang.ProcessImpl.start(Unknown Source)             ... 6 more   Feel free to ask me for more details.


Do Mr. Morden's invisible Shadow handlers go with him everywhere?

The few times we see Mr. Morden's invisible Shadow handlers, they are always right next to him. Such as this scene where Prime Minister Londo Mollari says goodbye to Morden's Shadow handlers.                                  Do they follow Mr. Morden even in public when there are crowds around him?  In this scene, Mr. Morden is at the Zocalo Cafe during a conversation with Vir Cotto. There are people around, so it might be awkward for the invisible Shadows to stand nearby. It would be strange if some random person tripped over the leg of an invisible Shadow.                                  Does he ever get some "alone time" such as when he sleeps or goes to the men's room?


Using multiple versions (allographs) of each glyph randomly

I wonder if there exists any system to make LaTeX print different versions of each letter randomly. The idea is to make a realistic handwritten or typewritten document where almost every «a» is a bit different from each other. Are there any font with dynamic parameters, such as the thickness of each part, to emulate this way different pressure patterns in a typewriter, for example?


Does text size and placement on page have an effect on SEO

As Google and other search engines keep trying to get more and more 'human' in terms of understanding what's good and what's spam, is it known if they take into account the size of a heading ie. an  thats font size is 40px is going to speak a lot more to the user than a  thats font size is 14px?  Similarly, does placement of text factor? E.g. a 300-word article at the bottom of a landing page (not in the footer but below the useful content) would be there just for seo purposes?  I know they look at things like text-indent:-9999px; and white text on a white background, but what about these more border-line practices that both have legitimate uses, but also the possibility to be spammy?


Correct Syntax to change default Screenshots and Screencapture save location?

I would like to change the default screenshot location for OS X Yosemite 10.10.3 using Terminal. But this command is not working, where subfoldername = "name of my sub-folder" I want to store my screenshots in.  author$ defaults write com.apple.screencapture location -string “$HOME/Desktop/subfoldername"


Why the discriminant of a system of linear equation=0 implies it has infinity many solution?

Given a system of linear equations:  $$(S):\begin{cases} a_1x+b_1y+c_1z=d_1\\ a_2x+b_2y+c_2z=d_2\\ a_3x+b_3y+c_3z=d_3 \end{cases}$$  And we use matrix to represent:  $$\left( \begin{array}{ccc|c} a_1 & b_1 & c_1 & x\\ a_2 & b_2 & c_2 & y\\ a_3 & b_3 & c_3 & z\\ \end{array}\right)= \begin{pmatrix} d_1\\ d_2\\ d_3\\ \end{pmatrix} $$Let  $$M=\begin{pmatrix} a_1 & b_1 & c_1 \\ a_2 & b_2 & c_2\\ a_3 & b_3 & c_3 \\ \end{pmatrix}$$  $$\begin{pmatrix} x\\ y\\ z\\ \end{pmatrix}=M^{-1}\begin{pmatrix} d_1\\ d_2\\ d_3\\ \end{pmatrix}$$  For (S) to have a unique solution, $det M\ne0$, and no solution for $det M=0$  But I am wondering why $det M=0$ also implies it has infinity many solution.


This is my first time posting on Math exchange. I have been self-teaching myself Mathematics and recently started learning some Algebra. I was posed the following questions, in which I would like to answer before I proceed, but having some trouble finding proper solutions. So the format will be question, and my answer.      What name do we give an element $a \in \mathbb{Z}_n$ that has a multiplicative inverse?   A modular multiplicative inverse of an integer $a$ is an integer $x$ such that $ax \cong 1 (\mod m)$. This means that the remainder after dividing $ax$ by integer $m$ is equal to $1$.      Give an example, for some $n \in \mathbb{N}$, of an element of $\mathbb{Z}_n$, that does not have a multiplicative inverse?   This question is throwing me off because - does the $n$ we speak of matter for both $n \in \mathbb{N}$ and $\mathbb{Z}_n$ ot solely $n$? My guess here would be $0$ because we cannot have an inverse of $0$.      Prove that multiplicative inverse are unique; an element $a \in \mathbb{Z}_n$ cannot have two multiplicative inverses.    Suppose that an element $a\in\mathbb{Z}_n$ has an inverse $a'$. Next, suppose that $a^*$ is also an inverse of $a$. Then, $a'$ is a solution to $a \cdot_n x=1$, and similarly $a^*$ has a solution to $a \cdot_n x=1$.   Lemma: Suppose $a'$ is multiplicative inverse of $a$ in $\mathbb{Z}_n$, then for any $b \in \mathbb{Z}_n$ the equation $a \cdot_n x=b$ has a unique solution, such that $x = a' \cdot_n b$.   By Lemma, equation $a \cdot_n x = 1$ has a unique solution, namely $x=a'=a^*$. Therefore, an element $a\in \mathbb{Z}_n$ cannot have two multiplicative inverses.    Thank you for the help. I would love any constructive feedback for these. If you can help me elaborate on some ideas, that would be really helpful also.  Thank you very much!


How do I write a python HTTP server to listen on multiple ports?

I'm writing a small web server in Python, using BaseHTTPServer and a custom subclass of BaseHTTPServer.BaseHTTPRequestHandler. Is it possible to make this listen on more than one port?  What I'm doing now:  class MyRequestHandler(BaseHTTPServer.BaseHTTPRequestHandler):   def doGET   [...]  class ThreadingHTTPServer(ThreadingMixIn, HTTPServer):      pass  server = ThreadingHTTPServer(('localhost', 80), MyRequestHandler) server.serve_forever()


& for running a command in the background

when i run   $ ls -R / &    although the & (which suppose to relegate the process into the background) i end up having to sit through the entire listing of my system. pressing CTRL+C or CTRL+Z doesn't help. what am i doing wrong?


I have an image inside a TikZ node. There should be a border around the image, with no gap. The border should have a specified line width. My problem is that the border seems to be drawn underneath the image. I use inner sep=0 to remove the gap between image and border. The effect is a border with half the intended line width, as demonstrated in the first example: \documentclass[tikz,margin=10pt]{standalone} \begin{document}      % Red border to distinguish from example image, which also has a border     \begin{tikzpicture}         \node[draw=red, inner sep=0mm, line width=10mm] {\includegraphics{example-image-a}};     \end{tikzpicture}      % Shows that part of the border was hiding behind the image     \begin{tikzpicture}         \node[draw=red, inner sep=10mm, line width=10mm] {\includegraphics{example-image-a}};     \end{tikzpicture}  \end{document}  I can think of two workarounds:  Set the inner sep to half the border width. That way the border should have exactly the space it needs. Keep inner sep=0 and set the line width to twice the intended value. Accept that the border is halved, therefore double it beforehand.  Is there a more elegant solution? Can we tell TikZ to draw the node border after the image? I could live with a small part of the image covered by the border.  Update after question was closed as duplicate: The linked question has significant overlap and helps me in my specific situation. Good! However, the question whether it's possible to draw the border above the node content is not answered by the other question and remains open. The answer to this question could prove useful to people who want the node border drawn last for other reasons. The linked question may not be useful for them.


There is something I fail to understand involving Leonhard Euler's identity:  It is well known that $(e^{2π})^i = 1$.  That means $\sqrt[i]{1} = e^{2π} ≈ 535.49 $.  But there's a rule that states $ \sqrt[a]{1} = 1$ , that means $\sqrt[i]{1} = 1$.  Applying this rule here: if $ a = b, a = c $ it means $ b = c $.  That means $ 535.49 = 1 $?


I've been asked to estimate the power consumption of the servers I run for my laboratory. I thought that I'd ask if there was some handy Linux commandline to get the power consumption of the server. It looks like powertop is useful for minimizing power consumption but it does not seem to show information that server A is using B watts.  Is there something buried in the /proc system that would help me out?


$$\sqrt{-5}*\sqrt{-3}=\sqrt{-1*5}*\sqrt{-1*3}$$ $$\sqrt{-1*-1}*\sqrt{5*3}=\sqrt{5*3}$$ $$=\sqrt{15}$$  But we all know that this below is right, $$\sqrt{5}i*\sqrt{3}i=-\sqrt{15}$$  So, please explain the formal result. And any confusion that have been arisen in my mind. This was shown to me by my teacher, and he wanted explanation, and I'm kind of stuck with it.  What's true and what's not?


Show that the space of functions $f: \mathbb{N} \to \mathbb{R}$ does not have a countable basis.  I really don't know where to start with this one! Could anyone help me?  Thanks


No background options other than default pictures

I am using freshly installed Ubuntu 19.10 on a Dell Precision 7530 laptop.  Under settings - background, I cannot change the background to anything other that the default pictures.  According to Ubuntu Desktop Guide » Settings » Display & screen » Change the desktop and lock screen backgrounds, "There are three choices displayed on top:.... "  This is incorrect. There is an "add picture" button, but no wallpapers, colors or pictures buttons.  I will appreciate any help getting this to work properly.  Thanks,  Paul


Anime about a red haired boy suddenly being transported into another world

So the anime I'm looking for is about a red haired boy suddenly being transported in another world in his modern world while going to his school with his blue haired friend (he was transported alone). Upon shocked at the fact he was in another place he tried desperately looking for his friend and trying to figure out why he is there while doing so he finds a man and a woman with a big filled bag go in an airship and leave (Maybe I got that wrong) he sees a red gem on the ground and picks it up. After a few more episodes he finds out he is the chosen one in the world who can save the world from chaos. The world had animals or creatures that is kind of similar to pokemon but with gems to power them up and without them beeing in a space in which we don't know what it's like when not in need for battle or any kind the animals connected with the gems turn into a small size enough to just have them sit on your shoulder or on your palm. What the red haired boy picked up was a beast inside that was very strong the red haired boy's animal partner was also red. The animals looks like plastic toys that came to life.  The blue haired friend who was with the red haired was shown in the series that he was also in the universe but was controlled by the evil person who wanted to get every gem stone and use it to make his animal more stronger than everyone else and wanting to destroy the world if I can remember the red haired met friends and traveled a lot of places in search of gemstones that can power up their partner animals the male and female with the ones with the filled bags who were the minions for that evil person would get in the way of red haired boy just like team rocket in pokemon but after the evil person said he had no use of them they were shocked and unable to process what to do after a while they sided with red haired boy and his friends but I think those two had ulterior motives?  I remember that the animals looked like dragons and dinosaurs but look like plastic toys and it's not Magi Nation please  I was looking for this in a website in which I used to watch it from and now I have found it apparently it's called Zinba the boy has brown hair not brown his animal partner is not a dragon but a lion I'm sorry......I'm wrong in so many things because I haven't watched it in a long time


Can a variable become statistically significant after the addition of another variable?

I am doing forward stepwise logistic regression. I have heard that its common for a previously statistically significant variable to become not statistically significant when one or more variables are introduced into the model. However, I have never heard of the opposite.  This is my case right now. The first variable in my model was $x_1$ (by lowest p-value), the second variable introduced was $x_2$. What's interesting is that $x_2$ is not statistically significant when it is modelled with Y alone. I am using R to do this though, I think this more of statistics question.


How can I programmatically display a block?

I'm developing a site using Drupal 8 beta-14. I've created a view block of different terms and now I want to display it using code. How can I display it programatically?  I used to do it in Drupal 7 using this code but I'm confused about Drupal 8.  $block = module_invoke('block', 'block_view', '4'); $text_block = render($block['content']);


Which one should I use here?  IN June 2014  or   ON June 2014  Why? Thanks.


Object visible in render mode, but not when rendering animation (with alpha values)

Hi –– I know this is a frequent question, but when I try to render my animation (cycles render), the viewport, and the files it outputs (I've tried PNGs and movies), are blank (transparent, as I'm using alpha background). I've gone through every tip I can find: the camera icon is enabled, the object is within distance of camera, I have a ton of lights, I restarted my computer, I'm rendering the correct scene and layer, I'm compositing correctly. I've also rendered this correctly in the past, but can't remember how I got it to work. Link to file here:


How to add content title as dropdown list for exposed filter?

I have a node ABC and using view where content is of type ABC. I have content title as a field in .  What is the way in which I can get a drop down for field content title in the filter criteria?


Can the present perfect continuous construct be used in passive voice?

Can the passive voice be used for sentences in the present perfect continuous?  I understand the present perfect and its passive voice (have/has built, has been built). However, the passive voice of present perfect continuous is unclear:   Active: They have been building this house for years. Passive: ???   I have seen suggestions of “This house has been being built for years,” but it sounds awkward and I don't recall anywhere else where two be verbs follow one another. Is this the right form to use?


When should I use Inline vs. External Javascript?

I would like to know when I should include external scripts or write them inline with the html code, in terms of performance and ease of maintenance.  What is the general practice for this?  Real-world-scenario - I have several html pages that need client-side form validation. For this I use a jQuery plugin that I include on all these pages. But the question is, do I:   write the bits of code that configure this script inline? include all bits in one file that's share among all these html pages? include each bit in a separate external file, one for each html page?   Thanks.


Can I recover a deleted VLC history file?

Is there any way to recovering recently used files of vlc in ubuntu? or How can I reach this text file which saved on my hdd?


Visual Studio Build Events not equal condition

Is there a way to have a not equal condition in build events ?  Like this:  if $(ConfigurationName) != Debug xcopy ...   Note that this is build event (batch-like syntax), not MSBuild task (which indeed supports != ).


What is a large sudden jump (or dip) and instantaneous recovery in a stock price

So why did the price tank all of a sudden and then came back to normal? What does it mean?


how long does the care take to reach the last pole algebra word problem

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


Since I didn't get an answer for this question, I ask now, does there exist a function whose:  limit as x approaches infinity is greater than 1, whose local or absolute minima is 1, and whose integral from 0 to infinity converges


I'm a noob, so I'm probably messing this up somehow, but can anyone tell me why the materials preview looks nothing like the render? Below, I have two screenshots to illustrate this (the better looking one is the material preview). Using Cycles fixes it, but I'm curious as to why it's not working properly in eevee. Thanks for any help!


Is there a way to set up a default folder for Windows Explorer?

I often use Win + E to pop up Windows Explorer, and then I usually have to navigate down into a few network folders to find my primary directory. Is there a way to set this folder as the default so that Windows Explorer always opens to this folder?


Evaluate $\sum^{n-1}_{k=1} {n\choose k}\frac{kn^{n-k}}{k+1}$

How can we evaluate:     $$\sum^{n-1}_{k=1} {n\choose k}\frac{kn^{n-k}}{k+1}$$   I observe that the expression has a similar format with the following formula: $$\sum^{n}_{j=0} {n\choose j}\frac{u^j}{j+1}=\frac{1}{n+1}\sum^n_{k=0}(u+1)^k$$ but I have no idea how to process further. A blind evaluation using Wolfram Alpha gives us $\frac{n(n^n-1)}{n+1}$


return a string of comma delimited numbers from a sql query

How can I return a comma delimited string using SQL Server?  select ID,  (<<SomeQuery from TableB B where (B.Id = A.TableBId)>>) from TableA A   and have it return results like:  1, '11, 12' 2, '22, 33'


Uniform convergence of $f_n(x)=nx^n(1-x)$ for $x \in [0,1]$?

I want to decide whether or not $f_n(x)=nx^n(1-x)$ is uniformly convergent or not. I have shown that $\lim_{n\to\infty} f_n(x)=0$ for $x \in [0,1]$.  Now $f_n(0)=f_n(1)=0$. And in $(0,1)$, we have $f'_n(x)=n^2x^{n-1}-n(n+1)x^n$. Putting this to zero gives $x=\frac{n}{n+1}$. Also $f_n(\frac{n}{n+1})=(\frac{n}{n+1})^{n+1}$. But that tends to $\frac{1}{e}$ as $n$ tends to $\infty$ which is not $0$ so we don't have uniform convergence, right?  Nonetheless we have $\lim_{n\to\infty} \int_0^1 f_n(x)dx=\lim_{n\to\infty} (\frac{n}{n+2}-\frac{n}{n+1})=0=\int_0^1 \lim_{n\to\infty} f_n(x)dx$.  Is all this right? I have some doubts, I mostly doubt my intuition in analysis... Thank you!


How do I calculate the voltage needed to heat up a wire to a certain temperature?

The wire I am using is standard temp. nitinol wire which needs to be heated up to 45 degrees Celsius in order to be effective (move). What voltage do I need to achieve this?


I've connected a graphics adapter to my Ubuntu 14.10 server. I'm using VirtualBox and need to enable access to the GPU under VM. The GPU is working on the server but not on the VM.  $ sudo lshw -C video   *-display                       description: VGA compatible controller        product: NVIDIA Corporation        vendor: NVIDIA Corporation        physical id: 0        bus info: pci@0000:84:00.0        version: a1        width: 64 bits        clock: 33MHz        capabilities: pm msi pciexpress vga_controller bus_master cap_list rom        configuration: driver=nvidia latency=0        resources: irq:151 memory:fa000000-faffffff memory:f0000000-f7ffffff memory:f8000000-f9ffffff ioport:f000(size=128) memory:fb000000-fb07ffff   I've installed the Guest Additions according the following explanation:   In addition, I went over     When I tried cat /proc/driver/nvidia/version according to the previous link, nothing happened. nvidia folder doesn't exist  Here is the error I get when I try to access the GPU from the VM:  modprobe: ERROR: could not insert 'nvidia_340': No such device Error using gpuArray No supported GPU device was found on this computer. To learn more about supported GPU devices, see www.mathworks.com/gpudevice. Error in main (line 2)  parallel:gpu:device:NoCUDADevice   Please advise.


On a map I used different symbols to indicate different structures. I used  to draw on the screenshot of a map website. I defined three types of symbols:   \tikzstyle{ARA} = [blue,regular polygon,regular polygon sides=3, draw, shape border rotate=180,inner sep=0pt,minimum size=10pt,fill=blue] \tikzstyle{wfluss} = [->,blue,thick] \tikzstyle{probe} = [red,diamond,draw,inner sep=0pt,minimum size=10pt,fill=red]   I want to have the legend (i.e. the part explaining the symbols) to be in the caption, i.e. that the red and blue symbols are explained in the caption.


Difficulties with deciding whether it is a plural or singular

I was solving some general questions about plural and singular. Then I came across a specific type of questions that have a hard time understanding.  Peter and Danny (is/are) going on a walk.  --> here we use 'are' because the subject of the sentence is "Peter AND Danny"  Peter, along with 100 other village people, walks.  --> here, we use "walk's'" because the subject of the sentence is Peter(singluar).  But the problem here is, why is the subject of the first sentence plural, while the subject of the second sentence is singular? Both of the sentences seem to talk about more than one person doing the action (walking), and yet, the subject of the first sentence is pleura, and the subject of the second sentence is singular...   Is it because of the difference between 'and' and 'along with'? If so, what happens if I use 'with', 'or', 'combined with', and so on? In what situation, does the thing become singular or plural?  I know that 'each, every, any, group of people' these types of words and phrases are singular. But if there are other nouns or phrases that I may be confused (like the one written above), it would be very nice if you could mention or talk about such additional things, as it would help me learn more about subject verb agreement. Thank you!


I have dataset of 15 features and the goal is to estimate a best fitting curve (regression). Now I want to use a deep learning technique for this purpose. Now I see that there are many architectures that can be used such as CNN, DBM or auto-encoder, etc.. Which one to go for. And I could not find any examples for how to use the same. A sample code would be of great help. Thanks  P.S. Some of the features are categorical. How do we handle that as well?


Why are two-usb heads needed (for external HDD cases)?

I've seen some external hdd-cases(for 2.5 inch) with two-head usb:    However, all hdd's are working with 1 usb-head.  I know that they are not enough to power 3.5inch hdds, so , what are use of two-usb heads?


Prove sum of $\cos(\pi/11)+\cos(3\pi/11)+...+\cos(9\pi/11)=1/2$ using Euler's formula


I recently installed Ubuntu to a USB drive and I can't get back to Windows

Just rewriting this post so it's more clear.  I'm unable to get back to Windows after I burned Ubuntu to my USB Drive after using a program called "Rufus".  Now, when I attempt to boot Windows, even after I took out my USB Drive, it will still boot to Ubuntu.  I'm not sure about what to do to get back to Windows, and I'm worried because I had important photos and videos there as well.  When I attempt to get back to it, it says "No partitions detected", so this may be the problem.  EDIT #2 : The problem may be that I didn't select the "Try Ubuntu without installing" option, but rather the second one (I forget the name...).


Not enough vertical spacing with booktabs and siunitx

I am using siunitx and booktabs, but I need a bit more vertical space between my units. Here is a picture of my problem:  Here is a MWE: \documentclass{article} \usepackage[utf8]{inputenc} \usepackage{siunitx} \sisetup{range-phrase=-,             detect-all,             decimalsymbol=comma,             round-mode=figures,             round-precision=3,             range-units=single,             per-mode=fraction,} \usepackage{booktabs}  \begin{document}  \begin{table}[htbp]     \centering         \begin{tabular}[]{llr}             \toprule              Parameter & Symbol & Wert   \\          \midrule              A       &A2         &\SI{1096}{\kg \per \cubic \meter } \\              B       &B2         &\SI{0,422}{\watt \per \meter \per \kelvin} \\              C       &C2         &\SI{3220}{\joule \per \kg \per \kelvin}    \\              D       &D2         &\SI{0,0274}{\kg \per \meter \per \second}      \\              \bottomrule         \end{tabular} \end{table}  \end{document}


How much cash can we carry to UK and Schengen area from India?

Will be traveling with my family of 4 to UK and Spain, although we have set up foreign currency cards in GBP and Euro, can we carry cash with us? If yes, how much and does it require some sort of declaration, etc.?


I just installed the latest version of Lubuntu on an older computer. Everything seemed fine until it tried to start up after the Installation was done and the dvd was ejected. It showed a Lubuntu screen , bu then just a small blinking white line, like an underscore, and blank screen. This just repeats over and over . Can anyone help? Btw, I don't know much about computers so basic is better.


error message with apt-get update command

When I update my system, I get the following errors:     Fetched 316 B in 22s (14 B/s)   Reading package lists... Done      W: GPG error:  trusty Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 6AF0E1940624A220   Please someone suggest me a solution to this.


I bought this new battery really cheap (it is really small and i needed a small 12v battery) but i am not sure of some things. First of all, it says it is 1.3Ah/20HR. Does that mean that it can deliever 1.3Ah for 20 hours? Like, i could power a 12v 1A light bulb (estimately...) for 20+ hours from it? Second of all, is this a deep cycle battery? ( i do not speak polish, so i do not understand the label). If i fully discharge the battery (9-10 volts) will it lose its capacity to store charge, or there is no problem? What is its optimal voltage? I used some rough google translate and it turns out that the "standby voltage" is 13.6-13.8 volts and the "usage" voltage is 14.5-14.9 volts. Isn't that too much for a 12v battery? Right now it is at 12.6V. Is it undercharged? Also, what is the voltage needed to charge it and is it a bad idea to charge it with a stepped up 5v power supply? (Phone charger, stepped up to the battery voltage required for charging)


APT problems after attempting to upgrade from Ubtuntu 17.04 to 18.04

Today I tried to upgrade my Ubuntu version from 17.04 to 18.04 following , but this didn't work:   $ sudo apt-get update Ign.:1 http://pl.archive.ubuntu.com/ubuntu bonic InRelease Ign.:2 http://pl.archive.ubuntu.com/ubuntu bonic-updates InRelease Ign.:3 http://pl.archive.ubuntu.com/ubuntu bonic-backports InRelease Ign.:4 http://pl.archive.ubuntu.com/ubuntu bonic Release Ign.:5 http://security.ubuntu.com/ubuntu bonic-security InRelease Ign.:6 http://pl.archive.ubuntu.com/ubuntu bonic-updates Release ...   I followed all steps, but sudo apt-get update gives me these errors. How can I revert these changes to first update to Artful and then Bionic?


Why is $5 + 5z + 5z^2 + ... + 5z^{11}  =  \frac{(5z^{12} - 5)}{(z - 1)}$ ? I don't understand how you can rewrite it to that.  Z is in this case a complex number: (for example: $z = 0,8(0,5 + 0,5i\sqrt{3}) = 0,4 + 0,4i\sqrt{3}$). Is it also possible to write the $5 + 5z + 5z^2 + ... + 5z^{11}$ with a summation (sigma) sign?


is int[pointer-to-array] in the C++ - standard?

As I have learned, one can write the following code:  char *a = new char[50]; for (int i = 0; i < 50; ++i) {     i[a] = '5'; }   It compiles. It works. It does exactly the same as  char *a = new char[50]; for (int i = 0; i < 50; ++i) {     a[i] = '5'; }   Is it just because:   a[b] is implemented as a macro *(a + b) by default and the fact that both code samples are valid is just an accident/compiler specific it's standardized somewhere and the outcome of such algorithms should be the same on every platform   It is reasonable to assume that addition should be commutative, but if we implement operator[] in that way, we have made something else commutative, what might not be what we wanted.  The interesting fact is that there is no pointer[pointer] operator, so operator[] is not a macro.  I know it's bad. I know it's confusing the people who read the code. But I want to know if it's just an accident and it will not work in a distant land where unicorns have seven legs and horns are on their left cheek.


Is mass an observable in Quantum Mechanics?

One of the postulates of QM mechanics is that any observable is described mathematically by a hermitian linear operator.   I suppose that an observable means a quantity that can be measured. The mass of a particle is an observable because it can be measured.  Why then the mass is not described by a linear hermitian operator in QM?


When filling out a standard W4 form, there is always the ability to withhold an extra amount of cash from each of your paychecks. Until now, working at part time jobs, I needed as much of my money as fast as I could get it, and I simply ignored the field.   Now, however, I'm at a point where I could spare a few dollars each check and I'm wondering if there is any value in doing this.   Does this amount help with anything in particular? If I choose to do this, can I at some point in the future stop having this extra amount withheld?   All answers are greatly appreciated.


Is there a way to find out if I need a transit visa for a layover in the UK?

Is there a website or some other way to find out if I need a transit visa for a short stop in the UK on my way somewhere else? Ideally this should give me the answer for all nationalities, and take into account any other visas I may have.


How can i align content inside other flex

I want to have a max 1100px div with spacebetween items but if i center .menu, space between isnt work...  What i can do? (or margin auto?)    .navbar {   display: flex;   justify-content: center; }  .menu {   max-width: 1100px;   background: red;   display: flex;   justify-content: space-between; }

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Torque relationship to speed in a DC motor

I have a conceptual doubt about torque-speed relation in a DC motors. It's probably a gap in my thinking but I'm posting this question anyway.  Torque and speed in a DC motor are said to be inversely proportional. But doesn't an increase in torque result in increase in Angular Acceleration and consequently, angular speed?  I know that back EMF/counter-EMF is responsible for the inverse relation but it seems counter intuitive to me. What happens to the angular acceleration, angular speed when the torque is increased and where does all that work go?


Possible values of $\int \frac{dz}{\sqrt{1-z^2}}$ over a closed curve in a region?

This is related to Ahlfors' problem #5 following section 4.4.7.  Let $\sigma$ be a path in $\mathbb{C}$ starting at $-1$ and ending at $+1$. Let $\gamma$ be a closed curve in $\mathbb{C}$ which does not intersect $\sigma$.    You can show there is an analytic branch of $\sqrt{1-z^2}$ defined on $\mathbb{C}\setminus\sigma$.  Question: What are the possible values of $\displaystyle\int_{\gamma} \frac{dz}{\sqrt{1-z^2}}$ ? Guess at answer: The set of values $2\pi k$ for integer $k$.    It feels to me like I should be able to reduce the situation to the integral $\displaystyle\int_{-1}^{+1} \frac{dz}{\sqrt{1-z^2}}$ on the segment of the real axis, then take advantage of the fact that the integral $\displaystyle\int_{+1}^{-1} \frac{dz}{\sqrt{1-z^2}}$ on the segment with the opposite orientation, and using the other branch of the function, does not cancel the first integral.  Another thought that I had was to try to relate the integral to a winding number.  This section on Ahlfors develops the general Cauchy theorem for curves homologous to zero, talks about multiply connected domains, and develops the notion of homology basis.  I would appreciate answers containing only hints, rather that full solutions, but they will be accepted if useful.  Thank you very much.  Note: The original problems as stated in the book is     Show that a single-valued analytic branch of $\sqrt{1-z^2}$ can be defined in any region such that the points $\pm1$ are in the same component of the complement. What are the possible values of $\displaystyle\int \frac{dz}{\sqrt{1-z^2}}$ over a closed curve in the region?


Boolean modifier "Cannot execute boolean operation"

I'm currently making a Rook chess piece on Blender. I've been trying to use the boolean modifier to subtract a part of the chess piece. The first application of the boolean modifier worked. However, as I was on my second attempt, I got the message "Cannot execute boolean operation".    I've already searched online for any possible solutions, but nothing seemed to have worked with mine. Could anyone help me with this?    Thanks in advance.


Little bobby tables language excluded from comments and titles?

I was just trying to  discover why his sql had injection problems, but adding a comment with drop (heretofore known as [d word]) and table (heretofore known as [t word]) together gave an error:  An error occurred during comment submission.   Basically trying to avoid any  problems I'd imagine.  , or at least didn't when that post occurred.  I didnt find any immediate examples on SO of users putting [d word] [t word] in the comments, but am pretty sure that I used to be able to do this.  It seems odd that SO would restrict my language in a comment.    Is the sanitation of comments so difficult that it cant allow this?  Are there any other phrases that I should look out for?  Could the error be a bit more specific so that it would be obvious the problem in the language?  EDIT:  Clearly this is a new issue, I just tried to submit this article with [d word] [t word]  together in the title and body and it gave me a generic error.  An error occurred submitting the question.   EDIT 2:  @Mysticial and I just discovered that it may have something to do with rep.  In which case, what is the rep to be able to put [d word] [t word] into your posts/comments?


I have a short question. Why XML files should be validated and not just well-formed?  I looked at several places for an answer to this question but I have not found a good one.


Is there any reason to diversify your investments across accounts at multiple/different brokers?

I have a few retirement accounts at Vanguard. I am considering opening a regular non-retirement investment account there. Is there any reason to diversify and open the new account with a different company like Fidelity, for example?  Note that I don't care about which company specifically (the ones listed are just examples). I want to know general information about diversifying between investment firms.


I would like to install git but when I type the command:   sudo apt-get install git   I am getting the error:  iiit is not in the sudoers file.  This incident will be reported.   The output of groups is:  iiit adm dialout cdrom dip plugdev lpadmin sambashare


Get list of registered custom post types

How can i get a list of all custom post types registered and show them on any template page.  I have code like this.  <?php      /**      * Template Name: Custom Post Types List      */      get_header();      $args=array(         'public'                => true,         'exclude_from_search'   => false,         '_builtin'              => false     );       $output = 'names'; // names or objects, note names is the default     $operator = 'and'; // 'and' or 'or'     $post_types = get_post_types($args,$output,$operator);      $posttypes_array = array();      foreach ($post_types  as $post_type ) {         $posttypes_array[] = $post_type;     }      echo "<pre>";     print_r($posttypes_array);     echo "</pre>";      get_footer();  ?>


How to obtain the maximum of this expression?

Find the maximum of this expression $\frac{3}{a^3+b^3 + 3} + \frac{3}{b^3+c^3 + 3} + \frac{3}{c^3+a^3 + 3}$ , where $a,b,c $ are real numbers such that $abc = 3$. What I have done is to use Cauchy-Schwarz Inequality to obtain: $\left(\frac{1}{a^3+b^3 + 3} + \frac{1}{b^3+c^3 + 3} + \frac{1}{c^3+a^3 + 3}\right) \left((a^3+b^3+3) + (b^3+c^3+3)+ (c^3+a^3 + 3)\right) \geq (1+1+1)^2 \geq 9$ Then we would have: $\left(\frac{1}{a^3+b^3 + 3} + \frac{1}{b^3+c^3 + 3} + \frac{1}{c^3+a^3 + 3}\right)\left(2(a^3 + b^3 + c^3) + 9\right) \geq 9$ $\left(\frac{1}{a^3+b^3 + 3} + \frac{1}{b^3+c^3 + 3} + \frac{1}{c^3+a^3 + 3}\right) \geq \frac{9}{2(a^3 + b^3 + c^3) + 9}$ By AM-GM inequality we have: $ a^3 + b^3 + c^3 \geq 3\sqrt[3]{a^3b^3c^3} $ $ a^3 + b^3 + c^3 \geq 3(abc) $ $ a^3 + b^3 + c^3 \geq 9 $ . . . I have gotten $\left(\frac{1}{a^3+b^3 + 3} + \frac{1}{b^3+c^3 + 3} + \frac{1}{c^3+a^3 + 3}\right)\geq \frac{9}{2(a^3 + b^3 + c^3) + 9} \leq \frac{1}{3}$ $\left(\frac{3}{a^3+b^3 + 3} + \frac{3}{b^3+c^3 + 3} + \frac{3}{c^3+a^3 + 3}\right)\geq \frac{27}{2(a^3 + b^3 + c^3) + 9} \leq 1$ After this, I am unable to break flip the inequality sign and obtain $ \leq $ sign instead in order to obtain the maximum. Much help appreciated


Is "Recent Documents" no longer provided in Windows 10 Start Menu?

I can find recent items settings, but these seem to only let me see recent items opened on a per-app basis i.e. I can look at my Microsoft Word icon and see recent documents opened by Word.  I can't see anywhere a simple "these are the last 10 documents/files you opened with any application" which is handy if I don't pin the apps in question to my startbar. This used to exist under Windows XP as "My Recent Documents":    Is there a way to get this functionality?  For example: I open doc.docx, sheet.xlsl, options.txt, picture.bmp with different tools and then see these items listed in one place indicating the files I most recently opened?


Why this happens when multiplying two doubles in .NET

I faced rather odd behavior when multiplying doubles.  Make a simple console application and try following code.  private static void Main(string[] args) {     var b1 = 3.1 * 100D;     var a1 = 4.1 * 100D;      // put breakpoint here and observe b1 and a1 values, to me they are       // b1=310, a1=409.99999999999994     Console.WriteLine(a1);     // notice that Console.WriteLine actually returns 410 }   I suspect this is something with the double representation in binary but I can't explain myself how it is possible, can you help me out?  Also if you cast a1 to decimal it becomes 410 somehow...  I tried compiling against C# 3.0 and C#7.0 both gave the same results. I am reproducing this in Visual Studio 2017.


I want to format my float number with 2 digit after decimal.     >>> x =5.0 >>> y=float("{:0.2f}".format(x)) >>> y 5.0   i want my output in this format:  5.00


How to input bibliography right after text using biblatex?

I heard that it's possible to do this with natbib but I am using biblatex with biber backend but I already have my bib file ready. Is there any way to do this with biblatex?  Pic related red underline is how I want it to work.


Case scenario:   Player 1: (9 points total)   3 cities (6 points) 3 hidden points  Player 2: (9 points total)   3 cities (6 points) 1 village (1 point) longest road  Player 3: (9 points total)   4 cities (8 points) 1 village (1 point)    It's turn of player3, he puts 2 roads and a village, which 'cuts' the longest road of player2, which gives the longest road award to player1 (+2 points for him out of his turn)  In his turn, player3 reaches 10 points. But player1 has 11 points (3 of them are hidden points)  Who wins?


I have bought a mobile through a friend in the US. What is the best way to get it to India without getting into trouble while departure from US and on arrival to India (customs)?


I am new to this. Just got this message below and I cant figure out how to fix it  Reading package lists... Done Building dependency tree        Reading state information... Done You might want to run 'apt --fix-broken install' to correct these. The following packages have unmet dependencies:  libasound2 : Depends: libasound2-data (>= 1.1.8-1) but 1.1.3-5 is to be installed E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).   Thanks a lot


Problem with bijection from $(0,1)$ to $(0,1)^{2}$?

I am trying to construct a bijection from $(0,1)$ to $(0,1)^{2}$, and I have come up with: $$f(x)=f(0.a_{1}a_{2}a_{3}a_{4}...) = (0.a_{1}a_{3}..., 0.a_{2}a_{4}...)$$ But I think there's a problem with this function. Let $$x=0.494949... \Rightarrow f(x)=(0.444...,0.999...) =(0.444,1)$$ which is not in $(0,1)^{2}$. There are more similar problems with repeating decimals, for example: $$f(.010909)=(0,.199...)=(0,.2)=f(0.02)$$ I couldn't find how anyone fixed this problem (though I did see someone mention that it was fixable). Any help would be hugely appreciated.


With $X$ compact Hausdorff space and $f:X \to X$ is continuous, prove there exists a closed set $C$ such that $f( C)=C$

Prove that if $X$ is a non-empty topological Hausdorff compact space and $f : X\to X$ is continuous, there exists a non-empty closed set $C \subset X$ such that $f(C)=C$.   My thoughts are to show that we can travel from a starting point $x$ through $f(x),f(f(x)),...,f^n(x)$ such that $f^n(x)=x$. that's we found a closed set. I can't seem to find the use of $f$ being continuous. Thanks!


How can I configure Ubuntu with GNOME 3 to dim screen when charger is unplugged?

I just installed Ubuntu 17.10 (with GNOME 3) on my new HP laptop, and I noticed that the screen does not dim when the charger is unplugged.   Is there a way to set up two brightness profiles, one for AC adapter, and one for battery?   Most of the tutorials say to install tlp, but from what I notice it does not change the brightness level... it seems to increase the battery life though.


trouble using a String variable as part of an 'if' condition

I need to use the 'checked' option in a radio button, but I want to use it dynamically. That is, either the right or the left button is pre-checked based on data from a database and the user can choose to accept or change it. To do this, I need the String "checked" as part of my radio button tag. I created two variables, chekR and chekL, with the plan that one of them would evaluate to "" while the other would evaluate to " checked". However, my IF condition fails to do the job. The value Right or Left comes from a form, and I tried printing it, which works fine, but the actual comparison is failing.  The variable passed from the form is stored as String D. If I try evaluating (D == "Right"), it returns a false every time. I tried two IFs (see code), I tried IF-ELSE, but no success.  String chekR = ""; String chekL = ""; if(D == "Left") { chekL = " checked";} if(D == "Right") { chekR = " checked";} <form action = update3.jsp>
 <input type="radio" name="PtEye" value="Right" <%=chekR%>>Right <input type="radio" name="PtEye" value="Left" <%=chekL%> required>Left
<input type="submit" value="Confirm"><input type="reset" value="Restore to original"></form>   I need the expression <%=chekL%> to produce either a blank or the word checked, depending upon the value of D.


How to ship an Android application with a populated database?

i created my first app and I would ship it with a local database that contains about 600 entries. I tried to hard-code this data in my class but i think it is not a good idea. So is it possible to copy a database to phone on first start of an application?


When is $f_{xy}(x,y)\neq f_{yx}(x,y)?$, where $f_{xy}$ and $f_{yx}$ denote the mixed (second) partial derivatives of a multivariable function $z=f(x,y)$.


What is the difference between Ehrenfest dynamics and Born-Oppenheimer Molecular Dynamics?

What is the fundamental difference(s) between Ehrenfest dynamics and Born-Oppenheimer MD? Also, in what situation(s) or case(s) one is preferred than the other one?


I have changed the root folder/files permission what should I do?

I have run the following command accidentally  sudo chmod 777 -R /   What should I do to get back to previous state?


Suppose $H$ is the only subgroup of order $o(H)$ in the finite group $G$. Prove that $H$ is a normal subgroup of $G$.  I've been trying this problem for quite a while but to no avail. What I can't understand is, how do you relate the subgroup being normal/abnormal to its order?  This question is from I.N.Herstein's book Topics in Algebra Page 53, Problem no. 9. This is NOT a homework problem!! I'm studying this book on my own.


Prove that the sequence is a Cauchy Sequence

The Sequence ${a_n}$ satisfies the following condition :: $|a_{n+1} - a_n|$ $\leq$ $\alpha$$|a_n-a_{n-1}|$,   $0<\alpha <1 $ for all natural numbers $n\geq2$ I approached the question like this :: In a field of real numbers, A sequence is convergent iff it's cauchy. So I tried to prove that the sequence is convergent using monotone convergence theorem. Using Induction, I first proved that the sequence is monotonous. And again using induction, trying to prove that it is bounded, but I am stuck here. Apart form this, I think applying Cauchy's general principle of convergence to prove this would be a more neater technique. Cauchy's General principle of Convergence states that the necessary and sufficient condition for convergence of a sequence ${S_n}$ is that for each $\epsilon$, there exists an $m$ such that $|S_{n+p}-S_n| < \epsilon$, $\forall n>m$ and   $p\geq1$ Please let me know how this can be approached by either of the ways. Thanks.


I have an object with two solidify modifiers added, but the modifiers are not visible in the view pane. How can I see the applied modifiers. This is in Blender 2.91


I'm trying to add textures to an object through the materials/textures panels, but no matter what I do, it won't work.  Render viewport mode just gives me black. Texture and material viewport modes give the color of the material but not the texture. Cycles render, blender game, blender render, all useless.  Maximum Draw Type is already set to "textured" and nodes don't work. I've been searching for an answer for hours and nothing's worked.  EDIT: There is no option to add an "image texture" anywhere in the materials tab. Not that it matters, because even the pre-loaded textures don't appear.  Here is the file:    EDIT EDIT: I also do not get an option to "unwrap" and even before that, I get nothing but a black texture.    EDIT EDIT EDIT: I get the brick texture on the body but not the hair. Using an image also gets just plain gray, not the image as a texture. And when I switch to Blender Render it turns bright orange.


How do I kill all processes running by my own non-root account?  I have some spinning smbd  processes that I caused from my windows machine and so I telnetted into the linux server and I want to kill those spinning processes.   I don't have authority to restart services or reboot the machine.


Seen many questions on this matter, but as I can not access CTRL-ALT-F1/2 I'm stuck into this loop.  It keeps asking for password, clean orpheants and back to login.  As I can NOT open any manager/control window it's somekind of strange behavior.  I can NOT login as myself OR as guest. :-(


I want to make my own hot key for Window's 10 Snip & Sketch. I have it installed on my OS and I can run it from the search menu. However, I can not find the app location of it. Anyone know where it lives?


Prove that $f:\mathbb R^n\to\mathbb R$ is affine if and only if it is convex and concave

Suppose $f:\mathbb{R}^n\to \mathbb{R}$ is both convex and concave, how to prove that $f$ is linear? or exactly speaking, $f$ is affine?  I thought for the whole day, but I cannot figure it out.   When I was working on this problem, I met another problem, are all the convex function continuous? If not, is there any counter example?  Actually, I can prove for one dimensional case, in which $f:\mathbb{R}\to \mathbb{R}$. However, I cannot generalize it into n dimensional cases.  By the way, I use definition for convex(concave) like this: $$f(t\vec{x}+(1-t)\vec{y})\leq(or \geq) tf(\vec{x})+(1-t)f(\vec{y}), \forall t\in[0,1].$$  Thank you so much!


Incomplete geometry tool in QGIS 2.18 'Las Palmas'

I just installed new version of QGIS which is 2.18 'Las Palmas'. Unfortunately, I cannot find vector conversion menu under geometry tool that I used to find in the previous version. I need to convert poly line to point, and polyline to polygon.


Trying to find a story about an immortal little girl

It's been maybe twenty years since I read this, so please forgive me for not remembering if it was a novel or a short story.   It's the story of a girl whose father was either a Greek or Egyptian alchemist. He had concocted an elixir which, if drunk periodically, grants immortality. The problem was that in order for it to work, the person drinking it couldn't have gone through puberty.   He gave the elixir to his son and daughter, and taught them how to make more. The children live through many centuries, but the son eventually stops taking it. He ages normally and eventually dies. The daughter continues to take it, and the reader learns her story while she is being interviewed, either by MDs, or psychiatrists.


Tamil letters scrambled & overlapped in xfce4 terminal

Tamil progressively overlaps and combination letters (உயிர் மெய் எழுத்து) do not merge in Xfce4 terminal:    Changing font and encoding doesn't help. how to overcome this?


I've just bought vs. I just bought vs. I bought

I bought an English grammar book 3 weeks ago. Is it correct to use any of the following sentences interchangeably to tell my friend that I bought the book, or is there a difference in meaning between each sentence?   I've just bought a book on English grammar, and it looks pretty good. I just bought a book on English grammar, and it looks pretty good. I bought a book on English grammar, and it looks pretty good.


Limit as n approaches infinity of (log(n!) / nlog(n))

I'm stumped with a limit. I know the answer (because I looked on wolframalpha) but I really want to know how to reach the correct answer. If you have any hints or tips on getting there I'd be most appreciative!


Show a non-empty open and closed set in R must be equal to R

I did this in class, and got no credit. We are now supposed to find a proof that works, can anyone help me with this? Thanks!


Does it exist some tikz register (let say \zoomfactor) that provides the curent scale factor. For example can I do something like :   \begin{tikzpicture}[scale=2]     \begin{scope}[scale=1.5]         \draw (0,0) circle (\zoomfactor);     \end{scope} \end{tikzpicture}   and to obtain circle of size 3=2*1.5 ?


How could a gap between array modifier created objects be closed?

Repeating a segment of a tire with the Array Modifier along a curve creates a litte gap.     Are there other options besides changing the the Array Modifier's relative offset? (This would require manually adjustment of the mesh)  Merge + First Last would destroy the mesh.


Calculating distance for each point along line in ArcGIS Desktop?

I have a polyline(Roads network) and points(Nodes) recorded along the line. I would like to calculate the distance for each point along the line in ArcGIS 10.1. Result will added in a new column and distance should be like Node 1 to - Node 2, Node 3, Node 4, Node 5....., Node 2 to - Node 1, Node 3, Node 4.....


I can show a hash code like this :              string str = "Hello World !";         MessageBox.Show(str.GetHashCode().ToString());   This is very simple , Message box return hash code of "Hello World !" . But I want to know when I use a code Like this :              MessageBox.Show(GetHashCode().ToString());   What will happen in this code ?! It give me a code like this "64923656" . if I run my application again it give me another code !!! Is it a random hash code ?! or this is a special word hash code ?!  Thank u for read .


Not complaining, but I just gained 500 points without reason

Last night I received 500 points extra without any (to me know) particular reason.  I still had a browser open so here's a screenshot of my stats of yesterday:    and currently it's:    with no actual trace of any cause.  Does anybody know what could have happened?


Sharing reputation for good comments that contribute to the quality of the answer

Sometimes a comment can add great value to an answer once its content has been incorporated into the answer. Perhaps correcting an error to an otherwise good answer, plugging a logic hole, rendering a more elegant solution, making an important clarification to explanations, etc.  Once the answer has incorporated the comment/suggestion, it would be nice to credit the commenter with a "slice of the pie" - ie share reputation gains between the answerer and the commenter, as recognition of their contribution as "co author" to the final answer.  The simplest way would be to make upvotes on comments yield reputation, but that barrow has been pushed before.  A few possibilities I could think of for sharing rep are:   The commenter can be added to the answer as a "reputation sharer" - reputation gains from the answer are split 50/50 from then on The answerer can make a "donation" of reputation from the answer to the commenter - eg if the answer has 4 votes, they can donate up to 40 reputation (there may have to be a requirement that this donation comes off the rep cap, so answerers don't distribute their excess rep when exceeding their rep cap) Upvotes made by the answerer to comments on the answer do get reputation (maybe 5 - transferred as per previous point)     Why bounty doesn't quite fit:  The bounty process is just too long winded and doesn't have an on-going effect if the answer turns out to be a really good one. The bounty is too delayed. They didn't answer, they just added value - I just want to give the comenter a pat on the back right there and then, and I don't mind giving up some erep to do it.


What techniques are out there that allow you to create a gradient like the ones pictured above? Is this a product of a specific brush set? Or is there some type of Noise Manipulation / Gradient Pattern going on in this image?


Is it possible to have automatic LOD (level of detail) on large scenes?

Objective: build a virtual suburb in blender for use in creating exterior shots (not realtime: shots will be rendered in Cycles).  The angles of these shots will not be known in advance, so it's impossible to guess in advance which elements need to be high detail and which can be low detail.  Large scene becomes unwieldy and incredibly memory-intensive with hundreds or even thousands of high-detail objects, especially when many are not in shot. Scene will be utilized by an artist on home computer, so excessive memory use is not viable. Convenience is the primary objective to maximize efficiency in setting up and rendering shots. Renderer to be used is Cycles.  The higher detail of the nearby models would not necessarily be provided by subdivision. A perfect example of the sorts of things I'd be working with are buildings; up close, they would have fully modeled doors, windows, and other small details like flags, while far away, those fine details could be baked into textures, made more rudimentary, or simply omitted altogether.  Is it possible to automatically swap out lower detail meshes/materials at long distance for these renders?  I am also interested in alternate solutions. Since there are only 20 layers available, the only alternate solution I can come up with would be to divide the suburb into sections and have a high-detail and low-detail version of each section put onto adjacent layers, which the artist will toggle based on the position of the camera and what is visible in the shot, but this would be less than optimal. Any other ideas are welcome.


We just discovered another server with a database on it. The database is owned by a SQL account SA, with the public and sysadmin roles. The other login is BUILTIN\Users, with only public. I can only connect through this one. SA is disabled, and even if it wasn't, we might not know the password.  Question: Is there any way to enable SA, or create another sql login with sysadmin?


There is a way to add custom split normal use Python API?

I can't find a way to achieve custom split normal effect. I want to use python (mesh normal/hard edge or soft edge) data collected from Maya then write to Blender mesh.    How to do it using the following Python API and how?  bpy.data.meshes[objName].normals_split_custom_set_from_vertices  bmesh module


Pages has crashed, my file is now corrupted and I'm trying to get the text from this file.  if I Right click on the file > Show package content > open index.zip , I can see a bunch of .iwa files which seems to contains my original text, especially "Document.iwa".  If I "$ nano Document.iwa" (because "$ file" only returns "data") I can see some of my text, but the overall seems crypted.  Does anyone know how to decode/read this kind of .iwa file or recover corrupted files?


I followed  procedure to reset the lost sudo password from the root prompt. Unfortunately, a password is requested to access the root prompt.  Am I missing some obvious step or is it not the right procedure? I am running Lubuntu on a Virtual Machine (W10 Host).


Is it quite expensive to Exchange euros to pounds and vice versa at Heathrow?

I am planning a visit to London. I was wondering what are the optimum choices to exchange euros to pounds and pounds to euros?  Is there an extra charge, apart from the exchange rate?  Is it safe to do it in Heathrow?  For a 2 day stay, eating finger food, not drinking and not spending a lot of money(except some cheap street souvenirs) what is fair amount of money to be needed?


Python idiom to return first item or None

I'm sure there's a simpler way of doing this that's just not occurring to me.  I'm calling a bunch of methods that return a list.  The list may be empty.  If the list is non-empty, I want to return the first item; otherwise, I want to return None.  This code works:  my_list = get_list() if len(my_list) > 0: return my_list[0] return None   It seems to me that there should be a simple one-line idiom for doing this, but for the life of me I can't think of it.  Is there?  Edit:  The reason that I'm looking for a one-line expression here is not that I like incredibly terse code, but because I'm having to write a lot of code like this:  x = get_first_list() if x:     # do something with x[0]     # inevitably forget the [0] part, and have a bug to fix y = get_second_list() if y:     # do something with y[0]     # inevitably forget the [0] part AGAIN, and have another bug to fix   What I'd like to be doing can certainly be accomplished with a function (and probably will be):  def first_item(list_or_none):     if list_or_none: return list_or_none[0]  x = first_item(get_first_list()) if x:     # do something with x y = first_item(get_second_list()) if y:     # do something with y   I posted the question because I'm frequently surprised by what simple expressions in Python can do, and I thought that writing a function was a silly thing to do if there was a simple expression could do the trick.  But seeing these answers, it seems like a function is the simple solution.


TikZ data visualization fails to load data from file

I'm trying to visualize some data with TikZ datavisualization library. Given foo.tex  \documentclass{article} \usepackage{tikz} \usetikzlibrary{datavisualization}  \begin{document} \begin{tikzpicture}   \datavisualization [ scientific axes, visualize as scatter ] data [ read from file=foo.dat ]; \end{tikzpicture} \end{document}   and foo.dat:  x, y 1, 2 3, 4 5, 6   It fails with the following error (repeated multiple times):  ! Package PGF Math Error: Sorry, an internal routine of the floating point unit got an ill-formatted floating point number `'. The unreadable part was near ''..  See the PGF Math package documentation for explanation. Type  H <return>  for immediate help.  ...                                                l.7 ... scatter ] data [ read from file=foo.dat ];   If I'd rather include data from foo.dat inline the document compiles normally.  What am I missing and how can I fix the problem?  I'm running TeXLive 2014 on Windows 7. All files use Unix line ending.  EDIT: I've removed all commas in my data file and explicitly set separator to \space, now it works.  One more quertion: TikZ documentation says:     /pgf/data/separator=<character> (no default, initially ,)   What does this mean? What is the difference between initial value and default value?


In American English, why is the past tense of "plan" spelt "planned"?

In American English, a lot of words are spelt with a single consonant plus "-ed", rather than two consonants as you often find in British English. Why isn't "plan" spelt with a single consonant?


Trying to prove that above stated question for $n \geq 1$. A hint given is that you should use $\frac{1}{(2k-1)(2k+1)}=\frac{1}{2}(\frac{1}{2k-1}-\frac{1}{2k+1})$. Using this, I think I reduced it to $\frac{1}{2}(\frac{1}{n^2}-(\frac{1}{3}+\frac{1}{5}+\frac{1}{7}+\cdots+\frac{1}{2n+1}))$. Just not sure if it's correct, and what to do with the second half.


How to export a model in blender along with the node setup?

I have created a mountains scene and added a lot of detail to it through displacements in node setups. Unfortunately when I try to export this whole scene, I only export the main model and not the node setups that modify the model when rendering it. Is there any way around this? Thanks in advance.


Electron flow and electric field question

My understanding is that the electric field lines of a proton goes outwards and an electron goes inwards, are theses properties the same for electron flow or is just for conventional current?  I think it makes more sense if the electric field lines of an electron is outwards instead of inwards, why? Protons have more mass, and should be producing an inwards electric field lines. Also, If the above is true, the electrons would flow with the electric field instead of against it in a closed circuit. Also, does that mean the magnetic field lines are reversed and the south pole magnetic field lines are going outwards?  I'm new to physics and I need help understanding the basics.


I have the following hierarchy:  class Base {   public Base(string sMessage)   {      //Do stuff   } }  class Derived : Base {   public Derived(string someParams)   {     string sMessage = "Blah " + someParams;     //Here I want to call the base constructor    //base(sMessage);    }  }


Someone who uses too many descriptive words to deceptively seem intelligent

What is a word in the English language to describe someone who purposely and excessively uses too many complex words, usually looking them up in a thesaurus, to seem more intelligent in their writings?  I found the term "waxing prolix". But, this doesn't seem to cover the fact that the person is doing this purposely to seem more intelligent than they actually are.  An example. "The feature is a pastiche of mediocrity and boorish cynicism. They are a political and artistic hack pandering to an assemblage of bitter philistines." The person could have just as easily said, "I'm not a fan of this movie or it's actors".   They simply sound like they are trying to sound more intelligent by using an arsenal of words that are not often used in the common tongue. Perhaps elevating themselves above their own audience?  Not a duplicate of  because the accepted answer to that question does not describe the word I am looking for.


What are the advantages / disadvantages Linux file hierarchy has compared to other OSs?

Does it make any difference whether a file system hierarchy sorts files by types and put them all under one directory (like all the binaries are under bin) or, on the other hand sorts them by package name (such as all Firefox files are under the firefox folder)?  I know there's this thread:   but it is far from being exhaustive, and if you read the comments - it seems that there is a justified disagreement there.  I don't know. Although I love Linux, it seems to me more reasonable to put all files under one folder. What do you think?


how to cite a review from the media online using bib.tex

How to cite a review from the media online using bib.tex? i.e. Shiller (2017). " Economy" Sciences. Jul.21.  Thanks in advance!


public Account findByInterest(String interest){     for(Map.Entry<Long, Account> e : accounts.entrySet()){         for(int i = 0; i < e.getValue().getInterests().size(); i++)         {             if(e.getValue().getInterests().get(i) == interest){                 return e.getValue();             }         }      }     return null; }   I'm trying to search in a HashTable of Objects to find an objected with a List of Strings, which has the same string as this method receives... What am I doing wrong?


Can you raise a number to an irrational exponent?

The way that I was taught it in 8th grade algebra, a number raised to a fractional exponent, i.e. $a^\frac x y$ is equivalent to the denominatorth root of the number raised to the numerator, i.e. $\sqrt[y]{a^x}$. So what happens when you raise a number to an irrational number? Obviously it is not so simple to break it down like above. Does an irrational exponent still have a well formed meaning?  The only example that comes to mind is Euler's identity, but that seems likes a pretty exceptional case. What about in general?


What should be the intuition when working with compactness?

I have a question that may be regarded by many as duplicate since there's a  one at MathOverflow. The point is that I think I'm not really getting the idea on compactness. I mean, in $\mathbb{R}^n$ the compact sets are those that are closed and bounded, however the guy who answered this question and had his answer accepted says that compactness is some analogue of finiteness. That's the first problem: In my intuitive view of finiteness, only boundedness would suffice to say that a certain subset of $\mathbb{R}^n$ is in some sense "finite". On the other hand there's the other definition of compactness (in terms of covers) which is the one I really need to work with and I cannot see how that definition implies this intuition on finiteness. Also, I feel it's pretty strange the covers people use when they want to deal with compact sets. To prove a set is compact I know they must show that for every open cover there's a finite subcover; the problem is that I can't see intuitively how one could show this for every cover. Also when trying to disprove compactness the books I've read start presenting strange covers that I would have never thought about. I think my real problem is that I didn't yet get the intuition on compactness. So, what intuition should we have about compact sets in general and how should we really put this definition to use? Can someone provide some reference that shows how to understand the process of proving (and disproving) compactness?


React functional component onChange problem

I'm new to React and try to create a simple integer input field that allows only numbers to enter. My code: import React, {useState} from "react";   export const IntegerInput = props => {      const maxLength = props.maxLength ? parseInt(props.maxLength) : 10;      const [intValue, setIntValue] = useState(props.value);      const inputMask = new RegExp(/^[0-9\b]+$/);      function handleChange(e) {         let inputValue = e.target.value;          let isNumber = inputMask.test(inputValue);         let isEmpty = inputValue === '';          if (isEmpty || isNumber) {             console.log('Update value to: ' + inputValue);             setIntValue(inputValue);         } else {             console.log('Invalid input: ' + inputValue);         }      }      return (         <input name = {props.name}                id = {props.name + '-id'}                type = "text"                className = {props.className}                maxLength = {maxLength}                value = {intValue}                onChange = {handleChange}         />     );  }  There is no error in the console and setIntValue is called only if needed but still can enter any character in the input field. What could be the problem? Please note, that I want to use "text" input and not "number" and I have the problem on the React side and not with the JavaScript.


How does Blender decide in which window it shows the render

This has puzzled me for years: How does Blender decide the window where it will display the rendered image when I hit F12 to render?


is there a way, how to use a object with a hair particle system to be emitted by another hair particle system?

I want to make a tree, so I made a tree and a plane for leafs and then used the particle system to emit leafs from the tree. That worked, but it didn't have enough branches and I am limited on faces per tree, so I made a branch with leafs (the same way: branch hair particle system with leafs as object), to emit it together with the leafs, but now I can't emit it with the leafs, all I get is a stick sticking from the trunk. can I somehow apply it or something, so that it would emit together?


Mentioning future work, that is now complete

I am presenting a paper at a computer science conference.  The paper I submitted to the conference mentioned future work that would significantly enhance the utility of the method.  This work was work that was always planned to be part of the same "project" as the work in the paper, indeed the conference paper is presented as a part way step towards doing X, and the future work is what takes it all the way.  The extension was quite involved (and not quite complete when I submitted the paper for review). They day before I left for the conference that work was "completed", in that a journal article about it was submitted for review.  Now when I present at the conference, in the conclusion I want to mention the future work – at least to the extent that it was described in the conference paper. Should I go into more detail? Should I even mention that "This work is now complete, and is under review for publication"?


What is the largest $n$ for which $n+5$ divides $n^5+5$

The largest $n$ for which $n+5$ divides $n^5+5$ is? $n$ being a natural number.


I have a sitemap.xml index fine with 3 XML files in it with around 120 pages for indexing. A year passed and I still have 1/3 of it indexed. All the most important pages for indexing are in 1st sitemap file, however Google takes a similar amount from each of the sitemap files instead...  How to make Google index all sitemap.xml records?  I have crawl rate set to MAX in GWT.


How to use possessive case in the following sentences?

We can say:    the smell of it   Can we say:    the arrival of him the son of me   And we can't say:   a suggestion of Mr. Smith (should be Mr.Smith's, right?)   Can we say:   a suggestion of Mr. Smith appointed at that time. (the modifier is long)


Usually regression models are evaluated using $R^2$. I understand this metric can be misleading too at times but as far as I understand the first parameter we look at is $R^2$.   There is another parameter which is often used and it is $MAPE$.  Both are functions of errors between predicted and true value. I am just wondering if there are certain cases where one should be preferred above another?   $R^2$ can become negative if being used on test data (on which the model is not built). Is this a reason to not use $R^2$ in these cases?  Can anyone give a qualitative insight on where $MAPE$ should be used and where $R^2$ should be used.


NTFS or Windows hibernation problem mounting a disk image

I have a disk image named: disk.img. I cannot mount this because I think it's messed up from Windows.  Here are some commands I've run:  sudo mount -o loop,offset=135266304 ./disk.img /mnt/temp  The disk contains an unclean file system (0, 0). Metadata kept in Windows cache, refused to mount. Failed to mount '/dev/loop8': Operation not permitted The NTFS partition is in an unsafe state. Please resume and shutdown Windows fully (no hibernation or fast restarting), or mount the volume read-only with the 'ro' mount option.     sudo ntfs-3g -o remove_hibernation ./disk.img /mnt/temp  NTFS signature is missing. Failed to mount './disk.img': Invalid argument The device '*' doesn't seem to have a valid NTFS. Maybe the wrong device is used? Or the whole disk instead of a partition (e.g. /dev/sda, not /dev/sda1)? Or the other way around?     sudo ntfsfix ./disk.img   Mounting volume... NTFS signature is missing. FAILED Attempting to correct errors... NTFS signature is missing. FAILED Failed to startup volume: Invalid argument NTFS signature is missing. Trying the alternate boot sector Unrecoverable error Volume is corrupt. You should run chkdsk.     file ./disk.img  ./disk.img: DOS/MBR boot sector MS-MBR Windows 7 english at offset 0x163 "Invalid partition table" at offset 0x17b "Error loading operating system" at offset 0x19a "Missing operating system"; partition 1 : ID=0xee, start-CHS (0x0,0,2), end-CHS (0x3ff,255,63), startsector 1, 4294967295 sectors     fdisk -l ./disk.img  Disk ./disk.img: 279.5 GiB, 300069052416 bytes, 586072368 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: gpt Disk identifier: *  Device       Start       End   Sectors   Size Type ./disk.img1 264192 586072063 585807872 279.3G Microsoft basic data     I really don't know what to do. I don't have access to Windows.  Anyone have any ideas?


Quick look at how much RAM is allocated to SQL Server?

With SQL Server 2005, you could look at the Task Manager and, at least, get a cursory look at how much memory is allocated to SQL Server.  With SQL Server 2008, the Working Set or Commit Size never really goes above 500 MB, even though the SQLServer:Memory Manager/Total Server Memory (KB) perf counter states 16,732,760.  Is there a setting where it will actually show the server memory in the Task Manager?  Or is it a result of them changing how memory is used in SQL Server


Append something to end of string using string substitution in vim

I have a file abc.txt which contains text like that:  ABC01 ABC02 DEF09 EFG92   I want to append 'I' to end of every line in the file. I am opening the file in vim editor and using the following command:  :%s/\n/I\n/g   But I am not getting the desired result.  When I used:  %s/$/I/g   I got what I wanted .  I am curious to know why the first method failed.


Create video from contents of webpage even if it's out of screen

I want to record the contents of a long webpage (even if it's out of my screen). Is there any tool to achieve that?  If video recording is not posible, take screenshot would be sufficient.  Any different approach is also welcome, i.e., if I just thought of a wrong solution and it's possible to enlarge windows without limits and then take a video or a screenshot of it, etc. then don't be afraid to tell.  For instance, if my display is 1280x800 for instance from superuser.com I would like to take a video that is 1280x4800 aprox. so that all the content is grabbed.  Any suggestion?  I'm using Mac OS X Mountain Lion, but any solution to another system would also be upvoted.


Executing the following program is producing the following result, please explain the reason why the value of sum is 120 and of price is 100.  double sum=10, price =100; sum+=price>=100?price * 1.1 : price; Syso(sum); Syso(price);   The output is 120 100


How many ways can N elements be partitioned into subsets of size K?

Let's have 2 numbers, N and K, where K divides N. The number of K-combinations from a given set S of N elements is a well known formula. Let's concatenate N/K groups (resulting in N elements) such as the resulting set is N. How many possibilities are there, i.e. what's the formula?  For instance:    N=4, K=2, C(4, 2) = 6 {1,2},{1,3},{1,4},{2,3},{2,4},{3,4}   The 3 possibilities are:     {1,2},{3,4}   {1,3},{2,4}   {1,4},{2,3}   I generated these combinations and I think the number goes like this:  (4, 2): 3 (6, 3): 10 (6, 2): 15 (10, 5): 126 (9, 3): 280 (10, 2): 945 (14, 7): 1716 (12, 4): 5775 (15, 5): 126126 (15, 3): 1401400   Apparently, the result always divides with (N-1).


How much of humor in a formal academic writing is considered as disrespect?

In a formal academic writing (in the everyday sense), is it appropriate to use phrases such as "step out on" to titillate the reader?   Since I am not a native English speaker, and since I have not yet accurately catched the general range of humor in the US, I wonder if using such phrases would be instead considered as a disrespect?


why do we need an optional keyword OUTER in sql?

LEFT JOIN and LEFT OUTER JOIN works exactly the same way.  Which means the keyword OUTER has no effect or it is optional.   Why do we include a keyword which has no effect in execution?


What is the purpose of double subscripts in variables in first order logic?

In "Introduction to Mathematical logic" by Elliot Mendelson , page $50$ and $56$ . I couldn't understand why they sometimes use double subscripts . For example , in page $50$ :  "We shall often indicate that some of the variables $x_{i_1},..., x_{i_k}$  are free variables in a wf $\mathscr B$ by writing $\mathscr B$ as $\mathscr B(x_{i_1},..., x_{i_k} )$ This does not mean that $\mathscr B$ contains these variables as free variables, nor does it mean that $\mathscr B$ does not contain other free variables. This notation is convenient because we can then agree to write as $\mathscr B(t_1,..., t_k)$ the result of substituting in $\mathscr B$ the terms $t_1,..., t_k$ for all free occurrences (if any) of $x_{i_1} , ... , x_{i_k}$ respectively."  Here , I didn't understand why they used double subscript notation in $x_{i_1},..., x_{i_k}$ instead of single subscript notation like in $\mathscr B(t_1,..., t_k)$ . In page $56$ :  "Moreover, instead of talking about the $n$-tuples of objects that satisfy a wf that has $n$ free variables, it is much more convenient from a technical standpoint to deal uniformly with denumerable sequences. What we have in mind is that a denumerable sequence $s = (s_1, s_2 , s_3 , ... )$ is to be thought of as satisfying a wf $\mathscr B$  that has ${x_j}_1 , {x_j}_2 ,  ... , {x_j}_n$ as free variables (where $j_1 < j_2 < ... < j_n$ ) if the $n$-tuple $\langle {s_j}_1 , {s_j}_2 ,  ... , {s_j}_n \rangle$ satisfies $\mathscr B$ in the usual sense."  Again , they used Double subscript notation in ${x_j}_1 , {x_j}_2 ,  ... , {x_j}_n$ but also there is this condition $j_1 < j_2 < ... < j_n$ . This just adds to the confusion to me because I don't understand at all why do they use Double subscript in the first place (To the point that it seems completely unnecessary. Now , I am completely new to subjects like first order logic and model theory , so I might struggle sometimes with the significance of some notation which actually has a good technical reason for using.This might be the case for this one as well.Can someone tell me the deep technical reason why we use double subscript sometimes below variables? (It could be possible that there are multiple reasons)


Why is $\mathbb{Z}[\sqrt{-n}], n\ge 3$ not a UFD?

I'm considering the ring $\mathbb{Z}[\sqrt{-n}]$, where $n\ge 3$ and square free. I want to see why it's not a UFD.   I defined a norm for the ring by $|a+b\sqrt{-n}|=a^2+nb^2$. Using this I was able to show that $2$, $\sqrt{-n}$ and $1+\sqrt{-n}$ are all irreducible. Is there someway to conclude that $\mathbb{Z}[\sqrt{-n}]$ is not a UFD based on this? Thanks.


What is the difference in *args, **kwargs vs calling with tuple and dict?

This is a basic question. Is there a difference in doing  def foo(*args, **kwargs):     """standard function that accepts variable length."""     # do something  foo(v1...vn, nv1=nv1...nvn=nvn)  def foo(arg, kwargs):     """convention, call with tuple and dict."""     # do something  mytuple = (v1, ..vn) mydict = {nv1=nv1, ...nvn=nvn} foo(mytuple, mydict)   I could do the same thing with both, except that the later has a weird convention of creating a tuple and dictionary. But basically is there a difference? I can solve the same computational problem of handling infinite things because dict and tuple can take care of that for me anyway?   Is this more of an idiomatic part of Python i.e a good Syntactic Sugar for things that you do anyway? I.e function is going to handle this for you!  PS: Not sure of so many downvotes though I agree this is a copy of  and probably it should be corrected in the duplicate information. And that question has recieved upvotes. So am I being downvotes for not being able to find that?


I have recently installed Ubuntu 14.04.1 LTS and I am having trouble using Amazon Instant Video. When I click on a video to play there is no option to play it, it just says that I can play it on a compatible device (kindle, phone,...) is there some package or something that I need to install?  Thanks for any help   I have successfully (I think) implemented the solution below but I still have the same problem.  After following the below I get:  nathan@nathan-S400CA:~$ sudo mkdir /etc/hal/fdi/preprobe    [sudo] password for nathan:      mkdir: cannot create directory ‘/etc/hal/fdi/preprobe’: File exists     nathan@nathan-S400CA:~$ sudo mkdir /etc/hal/fdi/information     mkdir: cannot create directory ‘/etc/hal/fdi/information’: File exists     nathan@nathan-S400CA:~$ /usr/sbin/hald --daemon=yes --verbose=yes     18:56:04.123 [I] hald.c:672: hal 0.5.14     18:56:04.123 [I] hald.c:673: using child timeout 250s     18:56:04.123 [I] hald.c:685: Will daemonize     18:56:04.123 [I] hald.c:686: Becoming a daemon     nathan@nathan-S400CA:~$ rm -rf ~/.adobe


If you view one person's memories in a Pensieve, then how use it in a third-person point-of-view ? I mean, since a person can't see what's happening behind him, how can that the person watching the said memory can ?


Show that if $a\mid b$ then $2^a-1\mid 2^b-1$

Show that if  $a|b \  \  then\ \  2^a-1|2^b-1$ I've seen this assertion in the proof of another problem but the author hadn't given any reason: [Original problem containing this assertion][1]   [1]:     . Seemingly simple,I have no idea how to progress in solving this problem!!


How does the metric for Most Successful Heroes differ from "Performance" in Heroes Played?

On my profile page, the Most Successful Heroes list Silencer, Spirit Breaker and Mirana.    However, on Heroes Played sorted by "Performance", there are heroes that I have a better performance with:    How do these two metrics relate?


Scaling has no effect in Blender Game Engine

I scaled an object up in Object mode, but when I start the game engine it returns to a much smaller size. This occurs when the object is a Soft Body, when I set it back to Static or to Rigid Body for physics it scales properly in the engine.  I have tried clicking the "Apply Transformation" button in Rigid Body Tools under the Physic tab in the object toolbar but it doesn't have a noticeable effect. (There isn't a Soft Body tools that I can find).  Is there a way to have scaling work for a soft body or do I need to go back and create a new larger mesh?


Let us say I have a master(m) slave(s) replication. Now, in the scheme of things, I introduce another database/schema(foo) not associated with the master in any way and I want this schema to be replicated into the slave(s). Can I do this?  AFAIK, this cannot be done. What is the best way to pull this off? The reason I want to do this is I want to join tables from foo with s/m.   The data replication need not happen in real time, can be a daily cron job too. Is mysqldump the way to go? Is there some hack that I can pull off?


Why does my item name not show up in 1.13?

I am in 1.13 Pre-Release 7 trying to make a one command creation and I need an item with a specific name. The command I use is /give @p diamond_sword{display:{Name:"Sword of Power"}} and it gives my a diamond sword, but it doesn't have the name.   This is me running the command.   This is the command not working.


Let's take: $$\int \frac{1}{x\sqrt{x+1}} \ dx  $$ I tried solve this by four hour, so I am asking for help


Can you connect to a game on Java edition from MCPE?

I've played Minecraft with my younger sister for a while now, but it has all been on MCPE. Now I am going to download it on my mac, but i don't know if she will still be able to join my world from her phone once I am playing on java edition. Will she?


I deployed an Apex trigger to production. Now I want to delete it - how can i do it? I tried turning it to inacive and uploading the outbound change set but it doesn't work. Thanks, Udi


WordPress auto login after registration not working

I looked up a bunch of threads trying to figure out how to automatically log a user in after registration, and came up with this.  function automatically_log_me_in( $user_id ) {     $user = get_user_by('id',$user_id);     $username = $user->user_nicename;     $user_id = $user->ID;     wp_set_current_user($user_id, $username);     wp_set_auth_cookie($user_id);     do_action('wp_login', $username, $user);     exit; } add_action( 'user_register', 'automatically_log_me_in' );   According to many responses I've seen, wp_set_auth_cookie and wp_set_current_user alone should be enough to log a user in by ID, but even this isn't doing anything.  Does anyone have any idea what I'm doing wrong?


Proof of ⊨∃x(Px⇒∀xPx) (Drinker's Paradox)

⊨∃x(Px⇒∀xPx) I was trying to solve the above drinker's paradox by contradiction and came up with the below expression by negating the above expression -  ⊨ ∀x ( Px ∧ ¬ ∀x Px )   This is where I got stuck because to distribute the universal quantifier I need all the variables inside the parenthesis to be bound variables but as x is a free variable I was not able to go further. Is the approach correct considering that the universal set is not empty and what should I do next?


Where can I find my .emacs file for Emacs running on Windows?

I tried looking for the .emacs file for my Windows installation for Emacs, but I could not find it. Does it have the same filename under Windows as in Unix?  Do I have to create it myself? If so, under what specific directory does it go?


tex4ebook displays accents as wrong characters

I'm trying to make an ebook, on windows 7 sp1, with both italian and cyrillic (and chinese in future). Minimum example with LuaTeX, Version 1.12.0 (MiKTeX 20.11): \documentclass[12pt,a4paper,openright,oneside]{book} \usepackage{fontspec} \setmainfont{Dejavu Serif} \setmonofont{Courier New} % \begin{document} aeeiou  \'a\'e\'i\'o\'u  àèéìòù  пожалуйста \end{document}   Compiling with lualatex.exe works fine:  but it does not with: C:\PATH>tex4ebook.exe -l .\file.tex "html5,charset=utf-8" " -cunihtf -utf8" that gives:  The problem is already there in the html file. I have also tried the command without the options, i.e. C:\PATH>tex4ebook.exe -l .\file.tex. The same apply with pdfTeX, Version 3.14159265-2.6-1.40.21 (MiKTeX 20.11), C:\PATH>tex4ebook.exe .\file.tex and: ... \usepackage[T2A,T1]{fontenc} \usepackage[utf8]{inputenc} \usepackage[russian,italian]{babel} ... \foreignlanguage{russian}{пожалуйста}  This example misses the cyrillic hen compiled with lualatex, but does not solve the accents problem either:  Thanks a lot.