Expected range of distances from the center within a sample of random points in a square

Suppose $n$ points are uniformly and randomly selected in  a square bounded by lines $ x=0,y=0,x=1,y=1.$ Let $X$ be the distance of a point from the centre $(1/2,1/2)$.Can we analytically calculate  the density function of the range of $X$.i did a MATLAB simulation  for k=1:1000          for i=1:1000                   x1(i)=rand();                     x2(i)=rand();                   y1(i)=rand();                   y2(i)=rand();                    d(i)=sqrt((x1(i)-0.5)^2+(y1(i)-0.5)^2);                   range=max(d)-min(d);          end          r(k)=range   end   avg=sum(r)/1000   plot(r)    I got the average value of range as 0.67 .References  and books for similar problems involving random   distances  between points  are also requested P.S:-Some experts are suggesting that my problem might be a duplicate of problem which talks about the average distance of a random point in   a square .While the two problems might be apparently similar but my problem is different in that its aim to find the density function of the range $R$  of the distance  of a random  point from the centre of the square ,possibly as a function of $r$ itself just as talk of the pdf $f(y)$ of a random variable $Y$.Further ,while it is relatively straight forward  to calculate the pdf of minimum and maximum of a rv ,it is an entirely different problem to compute the pdf of the range


Does anyone have a detailed plan that shows the current availability of Ubuntu Phone BQ Aquaris to European countries?


Let $b = 1 + \frac 1n$ and $a = 1 + \frac {1}{n + 1}$  Consider $\frac{b^{n + 1} - a^{n + 1}}{b - a} < (n + 1)b^n.$ we can substitute the given $a, b$ into this inequality to get  $\frac {(1 + \frac 1n)^{n + 1} - (1 + \frac {1}{n + 1})^{n + 1}}{b - a} < (n + 1)(1 + \frac 1n)^n$  which is  $\frac {a_nb -a_{n + 1}}{b - a} < (n + 1)a_n$   so that  $a_{n + 1} > (b -a)(n + 1)a_n - a_nb = a_n(-(bn - an - a))$   Does that work?  edit: I got a good answer on here, but I don't mind if this question is locked.


Proof for alternative definition of the derivative

I read somewhere recently that you can define the derivative as follows:  $$f'(x) = \lim_{h, k \to 0^+} \frac{f(x +h) - f(x - k)}{h + k}$$   I have been trying to prove this for about 2 hours, and can't seem to get it done. How should I proceed?  Edit: Assume $f$ is differentiable for all $x \in (x - \delta, x + \delta)$ for some $\delta > 0$.


Do time dilation tests prove that it exists or that atomic clocks are faulty?

Are the experiments that prove that time dilation exists, actually proving that an atomic clocks ability to keep time is affected by gravity/acceleration? How do we know 100% that that is not the case?  I am having trouble wrapping my head around how and why time dilation happens. I am not looking for a math explanation in any sense at all but a practical one. You can explain to me mathematically how a spinning spaceship creates a sense of gravity for people inside but I can take a bucket of water and spin it around and see and experience why that happens quite easily.  Is there any clear, practical explanation like this for time dilation?  Secondly how is this actually proven? How do we know for sure that atomic clock's frequencies don't fluctuate as gravity/acceleration changes? How do we know we are actually measuring "time"


Average Case Complexity for the Fibonacci Series

I am trying to find the average time complexity for the Fibonacci series using mathematical approach.  The best case is O(1), while the worst case is O(2^n). The Average case can be found by dividing the sum of times of all cases by the number of cases.  So, I believe that the average case can be found like this(using the sum of geometric series):    Thus, it should be still O(2^n) . Can you please tell me if my calculations and approach are correct?  The sample code for the Fibonacci() is shown below.  def Fibonacci(n):      if n==1:          return 0     elif n==2:          return 1     else:          return Fibonacci(n-1)+Fibonacci(n-2)


Can a bios based windows 10 system access gpt disk drive?

My computer has 2 hard disks. The first one is for the win 10 os. The second one is for data storage. They were both gpt style drives. Since it was a very old system, I decided to get it formated . I gave the system to the service centre to format the first HDD and install Windows 10 there .I asked them to not even touch the second drive. However after I received the system from them , I noticed that the uefi option was not enabled in the bios  settings. Naturally, I saw that the windows installation was done on a legacy bios environment. I also noticed that the second HDD was still in gpt style.  What surprised me,was the fact that though the second HDD was still in gpt style while the first one was in mbr style (to support legacy bios), I could still access and modify files in the second HDD.  My question is: I had previously known that gpt drives are not supported on mbr system. So, why was I able to access the secondary HDD(which was in gpt while the system was now a legacy bios system)?


Here is a simple table.  I want to merge 4 cells. I want to combine the three "this" cells area in this table. I thought I have to use multirow and multicolum at same time. However, I could not find how to use it.  If possible, could you post the modified LaTeX source code?     My LaTeX code:  \documentclass{article} \usepackage{multirow}% http://ctan.org/pkg/multirow \usepackage{hhline}% http://ctan.org/pkg/hhline \begin{document}  \begin{table}[ph] \begin{center} \begin{tabular}{c|c|c|c|c} \hline \multirow{2}{*}{Raaa (k)} & \multicolumn{4}{c}{C ()} \\ \hhline{~----}  & 3.3 & 2.5 & 1 & 0.5 \\ \hline \multirow{2}{*}{Raaa (k)} & \multirow{2}{*}{this} & this & 0.5 & 0.6\\ \hhline{~~~--}            &                       & this & 0.7 & 1.2 \\ \hline \end{tabular} \caption{R, C ripple size} \label{T:peak} \end{center} \end{table} \end{document}


If $x^{2}-x\in Z(R)$ for all $x\in R$, then $R$ is commutative.  I need to proof this theorem and I have something like this below. However, I do not know how to continue this proof.   $(x+y)^{2}-(x+y)=x^{2}+xy+yx+y^{2}-x-y=(x^{2}-x)+(y^{2}-y)+xy+yx\in Z(R)$  so $xy+yx\in Z(R)$


The question might look clear from a viewpoint of a non-physics guy but let me be more specific.  Can we say quantum leaps or waves or maybe the universe itself are completely indeterministic or do the scientists say that because of lack of information?  I am asking this because there are people telling me the you cannot know whether it is indeterministic because you might not have all the information needed to calculate the behaviour of the phenomenon. Also, some people argue that chaos is completely indeterministic.   Which is the case and why?


I can't get my WiFi to work on Kali Linux (Rolling 2017.2).   I recall that my wifi was working on earlier versions of Kali (and most of the guides I tried focused on those earlier versions) and I don't think it's a compatibility issue (drivers exist for this card and are/were working on other distro's). My Wifi card is this:  Network controller [0280]: Broadcom Limited BCM4360 802.11ac Wireless Network Adapter [14e4:43a0] (rev 03)   So I tried to do the standard things e.g. get the headers:  apt-get install linux-image-$(uname -r|sed 's,[^-]*-[^-]*-,,') linux-headers-$(uname -r|sed 's,[^-]*-[^-]*-,,')


How do you round a floating point number in Perl?

How can I round a decimal number (floating point) to the nearest integer?   e.g.  1.2 = 1 1.7 = 2


How to get the camera pose(4x4) matrix in blender python?

I am rendering a multiple-views of an object in blender-python API. I am able to render multiple views by moving the camera in a circular path. I would like to know how to get the camera poses for the rendered multiple views. I would want to save the camera pose information for each rendered view. I am new to blender and blender-python. Any quick help is appreciated? Thank you!


There is something I don't understand about the proof that . The same proof is present in Rudin's Principles of Mathematical Analysis.  Do we assume that our construction of $U_n$ must contain all points of $S$? What if we are only collecting evenly-indexed points of $S$ ($x_{2n}$)? We would still get an infinitely countable subset of $S$, and the rest of $S$ can be used to provide points for $V$. What am I missing?


How do I identify the role of a singleton in a well-tuned deck?

In this instance, I'm looking at Matt Sperling's , and there's one thing I don't get--what's the single  doing here?     Creatures:         4    1    4          Spells:         4    3    4    4    4    4    4          Lands:         4    3    9    4    4


How can I make a clickable Table of Contents?

Possible Duplicate:          I need links for the Table of Contents, so that I can navigate fast to different sections. I apparently need some package.  I tried the package url unsuccessfully.


How to give an epsilon-delta proof of this limit statement?

Although I know a couple of proofs of the statement $$ \lim_{x \to 0 } \frac{\sin x}{x} = 1, $$ I would like to be able to come up with a proof using the definition of the limit (i.e. an $\epsilon$-$\delta$ proof). Here $x$ is in radians of course.


Is it worth self-funding a PhD to attend a top 10 university?

What should I opt for?   Option A) very well paid PhD, around €3000 per month at a respectable university or;  Option B) a non-paid PhD, where I have to pay €2000 per year at one of the top 10 universities of the world?  EDIT: Actually they are both UK universities, Option B  is ranked between the top 10 in the world in engineering and tech, and I do get a scholarship that pays 18000 pounds which covers the difference between international student tuition and EU tuition. In Option A, I will be doing research in a good university and will be working alongside giants in the industry.


What is the difference between the sentences  "I would love/like to play cricket" and " I want to play cricket." Is there any difference in the moods?


Why does Stack Exchange require you to click to be turned down?

On any Stack Exchange site you can't vote for your own question.  So, Why does it give you the option, and then reject your vote? Would it not be better just not to have the option?  This way they are not receiving ?  An alternative would be to have the rating but not show the arrows...


I use a 13.04 system. Whenever the system boots up, the Bluetooth button is by default ON..Every time i have to manually disable it.Is there any way to disable this?


It seems that if I want to see unanswered questions, I can only list all unanswered questions, or unanswered questions with a specific tag.  If I try to use the search box in the top-right, it always seems to search ALL questions.  It would be more than useful to be able to search unanswered questions only.


$\forall t \in \mathbb{R}, e^{i \alpha_n t} \rightarrow 1 \implies \alpha_n \rightarrow 0$?

$\alpha_n \in \mathbb{R}$ is a fixed sequence of real numbers, for which the following holds:  $$ \forall t \in \mathbb{R}, \lim_{n \rightarrow \infty}e^{i\alpha_nt} = 1 $$  Is it necessarily the case that $\lim_{n \rightarrow \infty} \alpha_n = 0$?


How do I determine the make and model of a graphics card installed in a Dell Desktop?  Belarc Advisor doesn't identify anything, and the model, a Dell Optiplex 780, has 5 different models to choose driver downloads for on their website.


Let $G$ be a group with subgroups $H$ and $K$ with index $r=[G:H]$ and $s=[G:K]$. Show that: $[G:H\cap K]\leq rs$  I know it works with Lagrange, but I don't know exactly how.


Format numbers under 100 with a 0 in front

I've written a program that will print out adjacent NTS mapsheets but I want to format the numbers under 100 with a 0 in front of them.   ex. user enters 094m the output now is : "The adjacent map sheets are 104P 94N 95D 94L"  I want them to be: The adjacent map sheets are 104P 094N 095D 094L  These are the initial variables for the numbers:      int westBlockNumber = Integer.parseInt(blockNumberAsString);     int eastBlockNumber =  Integer.parseInt(blockNumberAsString);     int northBlockNumber =Integer.parseInt(blockNumberAsString);     int southBlockNumber =  Integer.parseInt(blockNumberAsString);


What does the Recycle Bin in Windows actually do?  Is it just a glorified folder and a holding place for soon to be deleted files, or does it do something specific?  Specifically, are files that are "moved" to the Recycle Bin actually moved on the hard disc, or are just the pointers to the files moved?  I am a fairly experienced user, I just wanted a more depth explanation of the Recycle Bin.


How can I get a debug log for the sites guest user/public profile? [updated for Spring 18]

Normally, you can put debug monitoring on a user by name to see the details on the error they're getting (especially for the non-descript Error Loading a Visualforce Page).  But when you are trying to debug a site page, how do you get a debug log for the guest user?  Update  As of Spring '18 Salesforce has dropped the requirement to include the debug_logs cookie to get debug logs for the force.com site requests.     In Winter ’17, we introduced a change that required guest users to set   browser cookies to activate debug logging. We had the best of   intentions: All your public site visitors share one guest user   license. Thus, when you enable logging for the guest user, the   visitors’ collective activities can fill your debug logs quickly,   hitting the log-size limit and causing log truncation. Sadly, people   didn’t like the Winter ’17 change. Setting cookies is complicated, and   the change made collecting debug logs for public users’ asynchronous   activity impossible. We’ve seen the error of our ways. Your public   users no longer need a debug_logs browser cookie to trigger logging.   This change applies to both Lightning Experience and Salesforce   Classic.


How do I change context to iframe in JavaScript?

I have an iframe in my webpage that includes the Draggabilly library and I want to find a way to use it from the parent frame by changing the scope. How do I do this?  In the JavaScript console, I'd just use the cd() function like this:  var iframe = document.querySelector("iframe"); var iframeDoc = iframe.contentDocument || iframe.contentWindow.document; cd(iframe); var draggie = new Draggabilly(".draggable");   This code worked fine in the console but when executed through the actual webpage, it gives me this error: ReferenceError: Draggabilly is not defined  Iframe code:  <script src="https://unpkg.com/draggabilly@2/dist/draggabilly.pkgd.min.js"></script>   Parent code:  <script>     var iframe = document.querySelector("iframe");     var iframeDoc = iframe.contentDocument || iframe.contentWindow.document;     cd(iframe);     var draggie = new Draggabilly(".draggable"); </script>


Is there a way to check my visit record to the USA if I am travelling on an ESTA ? I tried here:  but I don't think this is the correct page and it certainly has no record of me. Background: The airline I was travelling with made a hash of our check-in and as this was the only time (during this trip) my attempt to leave the US was recorded, I'd like to verify that the US knows I've left the country. Edit: I travelled several times to the US within the last year, always by air. None of the trips show up. I have a fairly standard name (all ascii characters, no hyphens etc) and I've tried putting both my first name and my first and middle name in the 'first name' box, and I always get " No record found for traveler." as the error. Another edit: So on a whim I didn't put the country that issued the passport (Germany) in the box, but the country I live in (UK) and then it finds my records. Now German passport numbers look very different from UK ones, so I have no idea how this happened -- I thought the passport gets scanned and it collects this information automatically. I'm not impressed.


Optimization of $2x+3y+z$ under the constraint $x^2+ y^2+ z^2= 1$

Let $x, y$ and $z$ be real numbers such that $x^2+ y^2+ z^2= 1$. Find the   maximum and minimum values of $2x + 3y + z$ .       How can I able to solve the problem? Thanks for your help.


What is the complexity of Gradient descent given sparsity $s$, condition number $k$ and size of the matrix $N$?

Given the Linear system   $$Ax = b$$  where $A$ is an $s$-sparse ($s$ is the maximum number of non-zero entries in $A$), $k$-conditioned ($k$ is the ratio between the highest and the smallest eigenvalue) matrix of size $N$, how can I express the time complexity of CG method based on those three parameters?  I have found out different questions in Stack exchange (,), but none of them considers all three parameters.


What is the purpose of a resistor on the non-inverting terminal of an Op-Amp Integrator?

I have seen this type of circuit design a few times, but am not sure why it is needed. Considering the schematic below, what is the purpose of resistor R3?


In calculating the integral $\int \frac{x}{x^3+5}\, dx$

Calculate the following indefinite integral:   $$ \int \frac{x}{x^3+5}\, dx $$   I understand that I should first do the  of the integrand and then integrate each part of the integrand to calculate the integral.   However, I don't know how to decompose $\frac{x}{x^3+5}$. Could anyone show me how?    [Notes from the editor. 9/4/19]   This integral is of the form $\int \frac{x}{x^3+a}\, dx$. More generally, it is an integral of the . See also the following similar questions:


how to find what script applies to certain elements

Is there any way to find out what script applies to certain HTML elements? With inspect element you can see the styles applied to elements and I'd like to check what javascript is applied also.  Example(this is what actually made me ask the question):    When you hover an item, a few things are happening and I'd like to know witch script(there are many scripts included in the html page) is responsible for the effects, and if all the scripts were merged into one .js file, would be nice to know the code responsible for the effect.  There are a lot of scripts and would be nice to know witch does certain things to the html elements.


I am trying to find a better/easier way to count alphabetic characters in a file or shell variable

I have a file containing the following text:  we are going to write something 1 2 3   wc tells me I have 1 line 9 words and 38 characters.  I'm looking to count the 26 letters only (a-z, no numbers or white spaces etc).  Here's my current solution:  grep -o [[:alpha:]] filename | wc -l   I really want to know if there is a "better" way to do this at the command line.


Why is Gilt a word when we have Gilded? Is this town big enough for the both of them?

We would never say "I builded my own house", and we would never say "I ment my fences" - as far as I can tell, words either went the d-to-t route, or they went the add-ed route. Gild, for some reason, went both ways. (Progressive, for its time!)  Is there any reason why this word bucked the trend and kept both past tense forms? I've reviewed existing material here on English SE and the interwebs in general and can't find any historical reasoning.


Render output does not match with Viewport display

Trying to render this scene. My render output looks different from how it appears in the viewport. The ocean looks different in the attached two images, one of rendered output & one viewport screenshot. trying to render in cycles. Applied Ocean modifier to create the ocean. Please guide me with your valuable feedback & comments. Also appreciate if any suggestions to make the scene look better or any scope of improvement elswhere


How can I know the number of rows/columns in an undefined array of pointers to a string in C?

#include<stdio.h> int main(){  char*s[]={"we will teach you how to","Move a mountain","Level a building","Erase the past","Make a million"};     printf("%u",sizeof(s));  return 0; }   Running this will output 20. Shouldn't the size be = no.of elements in each array x no of arrays x sizeof(char)? Also sizeof(s+1) prints 4 bytes.  Furthermore, how can I obtain the number of pointer arrays and no. of elements in each pointer array from the above mentioned code without hard coding?


Prove that the expression $5^{2n+1} \cdot 2^{n+2} + 3^{n+2} \cdot 2^{2n+1}$ is divisible by 19.

Prove that the expression    $$5^{2n+1} * 2^{n+2} + 3^{n+2} * 2^{2n+1}$$   is divisible by $19$.   I'll skip the basis step (as I have done last time) but I can conclude that it's only divisible by 19 for integers n ≥ 0 (or whole numbers).  II.  Assume that  $$5^{2k+1} * 2^{k+2} + 3^{k+2} * 2^{2k+1}$$ is divisible by 19. Then, $$5^{2k+3} * 2^{k+3} + 3^{k+3} * 2^{2k+3}$$ is divisible by 19.   Now this is where I get lost, I try to "dismember" the expression to get  $$5^{2k}* 5^3 * 2^k * 2^3 + 3^k * 3^3 * 2^{2k} * 2^3$$  I also try to get it similar to to the assumption to make use of the said assumption yielding $$5^{2k}* 5 * 5^2 * 2^k * 2^2 * 2 + 3^k * 3^2 * 3 * 2^{2k} * 2 * 2^2$$ $$5^{2k+1} * 5^2 * 2^{k+2} * 2 + 3^{k+2} * 3 * 2^{2k+1} * 2^2$$ $$5^{2k+1} * 25 * 2^{k+2} * 2 + 3^{k+2} * 3 * 2^{2k+1} * 2^2$$ $$50 * 5^{2k+1} * 2^{k+2} + 12 * 3^{k+2} * 2^{2k+1}$$ And this is where I get lost.. : (  Am I missing out something? Had I done it wrong? The number 19 is prime which makes it hard to handle for me. Thanks!  EDIT : After some pondering, I answered it this way : $$50 * 5^{2k+1} * 2^{k+2} + 12 * 3^{k+2} * 2^{2k+1}$$ I realized that 50 can be written as 38 + 12 (and 38 is a multiple of 19) Hence, $$ 38 + 12 * 5^{2k+1} * 2^{k+2} + 12 * 3^{k+2} * 2^{2k+1} $$ Factoring out 12, I get : $$ 38 + 12(5^{2k+1} * 2^{k+2} + 3^{k+2} * 2^{2k+1}) $$ 38 is divisible by 19 and the long expression is divisible by 19 (per the assumption) and qed. Is this correct ?


How to solve "Extra junk at end of file" when using apt?

I'm trying to configure some proxies for a guest virtual machine and now I'm getting:  sudo apt-get update E: Syntax error /etc/apt/apt.conf.d/95proxy:4: Extra junk at end of file   The content of the file is:  cat /etc/apt/apt.conf.d/95proxy   Acquire::http::proxy  "http://10.0.0.60:3128/" Acquire::ftp::proxy "http://10.0.0.60:3128/" Acquire::https::proxy "http://10.0.0.60:3128/"


Show that the vector space of all continuous real-valued functions is infinite-dimensional

Show that the vector space $C(\Bbb R)$ of all continuous functions defined on the real line is infinite-dimensional.   I get that if $C(\Bbb R)$ contains an infinite-dimensional subspace, then it is infinite-dimensional, but how do I prove that? Obviously $\Bbb R$ is infinite…


Prove that $\exists c>0$ s.t $\sum_{n\geq x}\frac{1}{n^2}\leq \frac{c}{x}$

$\mathbf{Question:}$ Prove that there exists a constant $c>0$ such that for all $x \in [1, \infty)$, $\displaystyle\sum_{n \geq x}\frac{1}{n^2} \leq \frac{c}{x}$  $\mathbf{Attempt:}$ Evidently,   $\displaystyle\bigg[\displaystyle\sum_{n =1}^\infty\frac{1}{n^2}-\sum_{j=1}^{\lfloor x \rfloor} \frac{1}{j^2}\bigg]{\lfloor x \rfloor}\leq x\displaystyle\sum_{n \geq x}\frac{1}{n^2} \leq \displaystyle\bigg[\sum_{n =1}^\infty\frac{1}{n^2}-\sum_{j=1}^{\lfloor x \rfloor} \frac{1}{j^2}\bigg]{\lceil x \rceil} $.   This inequality arises since,   $\displaystyle\bigg[\sum_{n =1}^\infty\frac{1}{n^2}-\sum_{j=1}^{\lfloor x \rfloor} \frac{1}{j^2}\bigg]=\displaystyle\sum_{n \geq x}\frac{1}{n^2}$.  Now, let $\lfloor x\rfloor=m$  $\displaystyle\lim_{m \to \infty}\bigg[\sum_{n =1}^\infty\frac{1}{n^2}-\sum_{j=1}^m \frac{1}{j^2}\bigg]m$  $=\lim_{{m \to \infty},{r\to \infty}}\bigg[\frac{m}{(m+1)^2}+\frac{m}{(m+2)^2}+\frac{m}{(m+3)^2}+...+\frac{m}{(m+r)^2}+...\bigg]=$  $\lim_{{h \to 0},{r\to \infty}}h\bigg[\frac{1}{(1+h)^2}+\frac{1}{(1+2h)^2}+\frac{1}{(1+3h)^2}+...+\frac{1}{(1+rh)^2}+...\bigg]=\displaystyle\int_{x=0}^\infty\frac{1}{(1+x)^2}dx=1$  We have, $\lceil x\rceil=m+1$ and $\displaystyle\lim_{m \to \infty}\bigg[\sum_{n =1}^\infty\frac{1}{n^2}-\sum_{j=1}^m \frac{1}{j^2}\bigg](m+1)=\lim_{m \to \infty}\bigg[\sum_{n =1}^\infty\frac{1}{n^2}-\sum_{j=1}^m \frac{1}{j^2}\bigg]m$  Thereby, we conclude, $\displaystyle \lim_{x\to \infty}x\sum_{n \geq x}\frac{1}{n^2}=1 $.  Therefore, from the definition of limit, $\forall \varepsilon>0$, $\exists G>0$ such that $\bigg|x\displaystyle\sum_{n \geq x}\frac{1}{n^2}-1\bigg|<\varepsilon$ $\forall x>G$. Choosing $\varepsilon =1$, we get $G=G_0$ such that $x\displaystyle\sum_{n \geq x}\frac{1}{n^2}<2$, for any $x> G_0$.   We set $\displaystyle c=\max\bigg\{2, \sup_{x\in [1,G_0]}x\sum_{n \geq x}\frac{1}{n^2} \bigg\}$  Is this procedure valid? Kindly verify.


How to run application from terminal forever?

I start jenkins web server using command java -jar jenkins.war. It works great. When I close terminal the application stops.  How to make it run even if I close terminal session ?


Proof if $f$ continuous in $x_0$ then there is a neighbourhood of $x_0$ so f bounded.

I have this question :  Proof if $f$ continuous in $x_0$ then there is a neighbourhood of $x_0$ so $f$ bounded.  I want to know if my proof is valid :  If continuous in $x_0$ then :  $$\lim_{x \to x_0} f(x)= f(x_0)$$  Therefore :  All $\epsilon>0$ exists $\delta>0$ so any $x$ that implies $|x-x_0|<\delta$ implies $|f(x)-f(x_0)|<\epsilon$.  Therefore for $\epsilon=1$ there is $\delta>0$ so any $x$ that implies $|x-x_0|<\delta$ implies $|f(x)-f(x_0)|<1$.  $|x-x_0|<\delta \rightarrow x_0-\delta<x<x_0+\delta$.  Lets choose $x_1,x_2$ that implies $x_0-\delta<x_1<x_2<x_0+\delta$  Therefore in $[x_1,x_2]$ from Weierstrass from theorem bounded there.


Determining why a transaction log file is so large

I have a SQL Server 2016 Enterprise database server that I have recently inherited.  One instance on this server has an application that uses two different databases.  One of these is the actual application database and the other is used to generate reports and dump data from the first.  The second database has several stored procedures that run at different times, including one that dumps data from a view into a CSV file for offsite storage of the data that runs every 15 minutes.  When I initially got this database, the recovery model was set to simple and a database backup was being taken nightly.  Since, I have changed the recovery model to full and changed the backup plan so that it is taking full backups twice weekly, differential backups twice daily and log backups every three hours.  However, even with this change, the transaction log for the second database is staying around 300GB.  Each transaction log backup is around 80GB.    I have plans to dig into how the stored procedures work and hopefully simplify some the way these things run, but that is going to be a long term project.  In the short term, I need to find a way to determine if the transaction log is being truncated correctly and if there is anything I can do to reduce the size of the transaction log on this database.  I've looked at the log with the fn_dblog function hoping to see if there were old transactions being stored, but most of the Begin Time and End Time records are null.    Other than a complete rewrite of the system (which is in the works), does anyone have any suggestions for getting a handle on this log file?


Authenticate Calls made to Salesforce webservice

I am using this exact example from trailhead   @RestResource(urlMapping='/Cases/*')     global with sharing class CaseManager {      @HttpGet        global static Case getCaseById() {        RestRequest request = RestContext.request;        // grab the caseId from the end of the URL        String caseId = request.requestURI.substring(        request.requestURI.lastIndexOf('/')+1);        Case result =  [SELECT CaseNumber,Subject,Status,Origin,Priority                     FROM Case                     WHERE Id = :caseId];        return result;       }   }   I used Workbench to invoke the GET HTTP method by following these exact steps   In Workbench, select GET. Enter the URI /services/apexrest/Cases/, replacing  with the ID of the record you created in the previous step. Click Execute.  This invocation calls the method associated with the GET HTTP method,  namely the getCaseById method. To view the response returned, click Show Raw Response.   So far so good, I see the raw JSON response as expected.   Now i want to give this endpoint to a third party, so that they can invoke this webservice from an external app, and get the response exactly as i got when executed from workbench.   My question is -    How do I authhenticate the call made by third party app?  Would the third party use the entire URI like     insead of just /services/apexrest/Cases/


Strange distortions in my background on desktop

So I updated my Ubuntu to 20.04 and many small squares with random pixel colors often appear on my desktop background. They are not glued to my screen though; they only appear on desktop. I've attached a screenshot.  .  What can I do?  PS: This has never happened on Windows, so I guess it must be OS-related.  Workaround: Restarting Gnome with Alt+F2 and then entering r solves the problem but only until the next restart.  Update: I changed the driver to NVIDIA's driver and still no luck. Some other random pixels are now on the background. And they remained there even after I changed the driver back to X.Org X server. And one other thing, those pixels go away when I change the background, but they come back the next time Ubuntu starts. Also, changing the background and changing it back to the same one returns the pixels too. It's somehow attached to that specific photo. Plus, Ubuntu is using my Intel graphics card by default, so I don't know if NVIDIA is the problem.  Temporary solution: I changed the desktop environment to Ubuntu on Wayland (you could do that from the login screen using the little tiny settings button if you reading this are also a noob like me :D) and it's fixed for now. I saw some stuff on the Internet that it uses more power, but for now I'll stick with it until I find a solution for the default DE. Will post if I find anything.


Internet and email access without a server

I have a small network of computers as a workgroup - NO Server. I only want 3 people to have internet and other 7 to have email only.  How do I do that?


Finite group theory - validity of the following conjecture

Wonder whether the following conjecture holds:  Let: $(G,*)$ - finite group, in which every proper subgroup is cyclic. Then: $(G,*)$ is cyclic.  Intuitively, there are no trivial counterexamples. However, I may miss something. Any help very appreciated!


Declaring option a4paper in \documentclass produces different margins than declaring it in \geometry

I have seen a similar question at  and the selected answer there implies that there is no difference in whether we use \documentclass[a4paper]{article} or if we use \usepackage[a4paper]{geometry}.  But my observations contradict the selected answer there.  Here is my code in file foo.tex:  \documentclass[a4paper]{article} \begin{document} Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas nec lobortis justo. Praesent ut scelerisque risus, sit amet mollis erat. Fusce at lacus at libero consequat consectetur.  Proin at vehicula ligula. Vivamus quis ligula id lacus aliquet ultricies. Vivamus tristique, velit vestibulum tincidunt fermentum, lacus sem euismod risus, ut volutpat augue dolor vitae est. Proin odio nunc, sollicitudin quis nisi a, sodales efficitur quam. Phasellus ex velit, porttitor vestibulum consectetur eu, maximus et nisi.  Nulla pharetra augue ex, quis scelerisque sem iaculis id. Aliquam in tincidunt quam. Praesent ac laoreet elit. Aenean varius ullamcorper dolor ac finibus. Proin est sapien, tempor nec mollis ut, ultricies et ante. Maecenas hendrerit velit non augue rutrum, mollis pharetra nisl auctor. Ut nisl mauris, porta ut nisi ut, elementum tristique nibh.  \end{document}   Here is another one in file bar.tex. The only thing that is different here is the usage of \usepackage[a4paper]{geometry} instead of \documentclass[a4paper]{article}.  \documentclass{article} \usepackage[a4paper]{geometry} \begin{document} Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas nec lobortis justo. Praesent ut scelerisque risus, sit amet mollis erat. Fusce at lacus at libero consequat consectetur.  Proin at vehicula ligula. Vivamus quis ligula id lacus aliquet ultricies. Vivamus tristique, velit vestibulum tincidunt fermentum, lacus sem euismod risus, ut volutpat augue dolor vitae est. Proin odio nunc, sollicitudin quis nisi a, sodales efficitur quam. Phasellus ex velit, porttitor vestibulum consectetur eu, maximus et nisi.  Nulla pharetra augue ex, quis scelerisque sem iaculis id. Aliquam in tincidunt quam. Praesent ac laoreet elit. Aenean varius ullamcorper dolor ac finibus. Proin est sapien, tempor nec mollis ut, ultricies et ante. Maecenas hendrerit velit non augue rutrum, mollis pharetra nisl auctor. Ut nisl mauris, porta ut nisi ut, elementum tristique nibh. \end{document}   But the output from both files are different. Here is a side by side comparison with foo.pdf on left and bar.pdf on right.         I have three questions:   Why are the two outputs different? Looks like it is due to different margins. Am I right? Do these outputs contradict the selected answer at  ? Is there a best practice regarding where a4paper should be declared?


I have a Bevel modifier but I want some seams to be tighter than others. How can I do that?

So I'll explain my crude drawing. So I like that the bevel is doing to the outside edges but seams on the inside I want much tighter. Is there anyway to change those?


Application to edit TeX code on my smartphone

I'm thinking of installing an application to edit TeX code on my smartphone with the Android operating system.  Does anyone know any?  I thought I'd ask in another app recommendation site, but I do not think they know the TeX language.


He is one of the men who do/does the work

Let us say, I have been given two sentences in an MCQ test and I need to pick up the correct one.   He is one of the men who do the work. He is one of the men who does the work.   Somehow, I lean towards the second one ("It is I who am to blame", the one sentence memorized to take care of cases like this), but I have found some grammar books supporting the first one.


Add square brackets to authoryear bibstyle

I am trying to get square brackets for both all cite references in the text and in my bibliography list at the end of my document.  I have got the square brackets for the cite refs inside the text working as you can reproduce with my sample document:  \documentclass{book}  \usepackage[T1]{fontenc} \usepackage[scaled]{} \usepackage[ngerman]{babel} \usepackage[utf8]{inputenc}  \usepackage[     bibstyle=authoryear,     citestyle=authoryear,     backend=biber,     sortlocale=de_DE,     natbib=true,     url=true,     doi=true,     eprint=true, ]{biblatex} \addbibresource{bibliography.bib}   \makeatletter  \newrobustcmd*{\parentexttrack}[1]{%   \begingroup   \blx@blxinit   \blx@setsfcodes   \blx@bibopenparen#1\blx@bibcloseparen   \endgroup}  \AtEveryCite{%   \let\parentext=\parentexttrack%   \let\bibopenparen=\bibopenbracket%   \let\bibcloseparen=\bibclosebracket}  \makeatother  \begin{document}  \chapter{The first chapter} As \parencite{Sattler} pointed out...   \nocite{*} \printbibliography   \end{document}   However I need to have additional square brackets containing the cite reference in the bibliography list as shown here:    For the sake of completeness here is a small sample snippet of my bib-file:  %% Saved with string encoding Unicode (UTF-8) @book{Sattler,     Address = {Weinheim},     Author = {Sattler, Klaus},     Date-Added = {2013-09-28 21:46:33 +0200},     Date-Modified = {2013-09-28 21:46:33 +0200},     Isbn = {35272627271},     Publisher = {VCH Verlagsgesellschaft},     Title = {Thermische Trennverfahren: Grundlagen, Auslegung, Apparate},     Year = {1988}}  @book{Schwister,     Address = {M{\"u}nchen},     Author = {Schwister, Karl},     Date-Added = {2013-09-24 12:32:57 +0200},     Date-Modified = {2013-09-24 12:33:09 +0200},     Edition = {4., aktualisierte Aufl},     Isbn = {9783446424357},     Publisher = {Fachbuchverlag Leipzig im Carl-Hanser-Verlag},     Title = {Taschenbuch der Verfahrenstechnik: mit 49 Tabellen},     Year = {2010}}   How can I achieve those additional reference listings in the bibliography (like having in bibstyle=alphabetic or bibstyle=numeric)?


On my Ubuntu machine, if I don't have a particular application installed, the message often points me to the correct package.  Example:  $ rz The program 'rz' is currently not installed. You can install it by typing: sudo apt-get install lrzsz   Is there any way to automate the invocation to install, so that my shell will execute sudo apt-get install .... on its own if such a situation arises?  Alternatively, is there a shortcut so that the entire sudo a ... sz command doesn't have to be typed/copied in?  To clarify:  does not meet the requirements because:   This fails for the example above. lrzsz is the package but rz is the application. apt tells me the right package to install; I don't want to use $1. This would apply for java etc. too.... It can get quite irritating in practice as it offers to install my typos; e.g., if I type ptyhon instead of python:  $ ptyhon Do you want to install ptyhon? [N/y] y Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package ptyhon


Story with multiple 'third planet' races

I'm looking for the name and author of a novel (or possibly novella). I first read this in the seventies, and might be older than that. It might have been written for teenagers.  The story takes place on a planet inhabited by a primitive humanoid race, roughly stone age if I remember rightly. Visiting this planet is a small team from a more advanced race, also humanoid and with spacefaring technology (obviously!). They are either there to help or observe, no nefarious purposes. I think they are avoiding contact with the primitives, at least initially. It's explicitly mentioned that the planet they are visiting is the third one of a medium sized star, just like their own homeworld. Also orbiting round the planet is an even more advanced race, using high tech to remain hidden from both the others. They are observing the whole situation, and again its mentioned that this is a 'third planet', like their own homeworld.  I'm a little bit hazy on the rest of the plot, but I think the super-advanced race end up revealing themselves, even though they are not supposed to.  The story is told from the viewpoints of both the second and third races (maybe also the first, I forget)  EDIT: For the record it turns out my recollection was faulty, and the second race are indeed coming to the planet for nefarious purposes. And the planet is at the medieval stage, not stone age.


Will someone please explain how a basic  works? I have a feeling it has something to do with pressure and the Venturi effect, but I'd really like to know precisely how they work as completely as possible.  If you know, please feel free to use  as a reference in explaining.  EDIT: Please note that I'd specifically like to know how atomizers of the type pictured in the link I provided, the kind with a spring-based finger pump, work. I'm not talking about e-cigarette atomizers or .


Need help with a question regarding the Big Oh

In class we are currently covering upper/lower bounds, big Oh and omega and the like. I am pretty good on the "typical" functions one would do, but at a complete loss at "general" statements. This ons function, for example:  $$\forall f\in\mathcal{F}: \lfloor \sqrt{\lfloor f(n)\rfloor }\rfloor \in O(\sqrt{f(n)}).$$  the domain F by the same is all natural numbers that return a real positive number when inputted. My first instinct with something like this is to remove the floors, the general strategy I though to solve this is remove the outer floor, then get rid of the square root, and then the inner floor. But I have no idea how to go about this or if this is even the right way to do it.  Help please? Thanks in advance.


Additional author causes biblatex to ignore maxcitenames

I have 2 books and in the latter one an additional author is added. This somehow causes my set maxcitename in the options for biblatex to be ignored. In the attached picture you can see how it looks like now. I would like the second book to adhere to my maxcitename option. I thought it would be related to this question:  but the answer did not change anything for me.  My MWE:  \documentclass{article} \usepackage{filecontents} \usepackage[ngerman]{babel} \usepackage{csquotes} \usepackage[style=authoryear, backend=biber, maxcitenames=2, uniquename=false, uniquelist=false, maxbibnames=10]{biblatex}   \begin{filecontents*}{\jobname.bib} @book{Hartung.2007,  author = {Hartung, Joachim and Elpelt, B{\"a}rbel},  year = {2007},  title = {Multivariate Statistik: Lehr- und Handbuch der angewandten Statistik}, } @book{Hartung.2009,  author = {Hartung, Joachim and Elpelt, B{\"a}rbel and Kl{\"o}sener, Karl-Heinz},  year = {2009},  title = {Statistik: Lehr- und Handbuch der angewandten Statistik}, } \end{filecontents*} \addbibresource{\jobname.bib}  \begin{document}     \cite{Hartung.2007} \cite{Hartung.2009} \printbibliography \end{document}     instead of the 3 names appearing I want this: "Hartung et. al. (2009)"


Can I use 45/60/85W MagSafe era MacBook chargers interchangeably?

I have a 13" Macbook Pro that came with a 60W power adapter and a 15" Macbook Pro that came with a 85W power adapter. There seems to be disagreement . Can I use either adapter with any portable Mac?


How would you calculate the input impedances of these circuits?

How would you calculate input impedance of this circuit? I have tried and obtained these calculations for 1.3, but apparently my teacher told me that I am supposed to ignore the 2 10k resistors. This was my exam question that I was absolutely clueless about, so I am reviewing them here.


I get this error in Ubuntu Studio 18.04 LTS. What can I do to fix it as I am not able to update my system.  "E: Malformed entry 52 in list file /etc/apt/sources.list (Component)"  cat /etc/apt/sources.list # deb cdrom:[Ubuntu-Studio 18.04 LTS _Bionic Beaver_ - Release amd64 (20180426)]/ bionic main multiverse restricted universe  # See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to # newer versions of the distribution. deb http://in.archive.ubuntu.com/ubuntu/ bionic main restricted # deb-src http://in.archive.ubuntu.com/ubuntu/ bionic main restricted  ## Major bug fix updates produced after the final release of the ## distribution. deb http://in.archive.ubuntu.com/ubuntu/ bionic-updates main restricted # deb-src http://in.archive.ubuntu.com/ubuntu/ bionic-updates main restricted  ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team. Also, please note that software in universe WILL NOT receive any ## review or updates from the Ubuntu security team. deb http://in.archive.ubuntu.com/ubuntu/ bionic universe # deb-src http://in.archive.ubuntu.com/ubuntu/ bionic universe deb http://in.archive.ubuntu.com/ubuntu/ bionic-updates universe # deb-src http://in.archive.ubuntu.com/ubuntu/ bionic-updates universe  ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu  ## team, and may not be under a free licence. Please satisfy yourself as to  ## your rights to use the software. Also, please note that software in  ## multiverse WILL NOT receive any review or updates from the Ubuntu ## security team. deb http://in.archive.ubuntu.com/ubuntu/ bionic multiverse # deb-src http://in.archive.ubuntu.com/ubuntu/ bionic multiverse deb http://in.archive.ubuntu.com/ubuntu/ bionic-updates multiverse # deb-src http://in.archive.ubuntu.com/ubuntu/ bionic-updates multiverse  ## N.B. software from this repository may not have been tested as ## extensively as that contained in the main release, although it includes ## newer versions of some applications which may provide useful features. ## Also, please note that software in backports WILL NOT receive any review ## or updates from the Ubuntu security team. deb http://in.archive.ubuntu.com/ubuntu/ bionic-backports main restricted universe multiverse # deb-src http://in.archive.ubuntu.com/ubuntu/ bionic-backports main restricted universe multiverse  ## Uncomment the following two lines to add software from Canonical's ## 'partner' repository. ## This software is not part of Ubuntu, but is offered by Canonical and the ## respective vendors as a service to Ubuntu users. deb http://archive.canonical.com/ubuntu bionic partner deb-src http://archive.canonical.com/ubuntu bionic partner  deb http://security.ubuntu.com/ubuntu bionic-security main restricted # deb-src http://security.ubuntu.com/ubuntu bionic-security main restricted deb http://security.ubuntu.com/ubuntu bionic-security universe # deb-src http://security.ubuntu.com/ubuntu bionic-security universe deb http://security.ubuntu.com/ubuntu bionic-security multiverse # deb-src http://security.ubuntu.com/ubuntu bionic-security multiverse deb https://dl.winehq.org/wine-builds/ubuntu/bionic main # deb-src https://dl.winehq.org/wine-builds/ubuntu/bionic main # deb-src https://dl.winehq.org/wine-builds/ubuntu/bionic main   Thanks, Raoul


what is the advantage of using the GPU rendering options in Android?

Here is a screenshot:    Will it speed up my device to enable the two GPU options?


How should I capitalize "Keep On Running/Keep On Moving" and "Walk On Down"?

These are the song titles by Spencer Davis Group/Deep Purple and Aerosmith accordingly, I know that if a preposition is a part of a phrasal verb it is capitalized, but everywhere I look, I see "Keep on Moving" (I'm guessing by the logic of importance of words) and so on, what is the correct variant here?


Has Ubuntu been patched against the KRACK attack?

According to this  a severe flaw in wpa2 protocol has been published making many systems using WiFi vulnerable to an attack. Should I be worried and has a patch been issued for Ubuntu?


Will I be able to get an interface that is like Gnome Classic in Ubuntu 14.04?

For a while I departed from Ubuntu to use Linux Mint because I really don't like Unity, or Gnome 3's most recent interface.  I was fine with what was called "Gnome Classic", but I feared it was being neglected because there were some significant bugs that lingered without improvement for a while.  Unfortunately, while I like the MATE interface in Linux Mint, Mint itself lacks the level of community support that Ubuntu has. Mint has development and support issues. Not to disparage their efforts, I think they've done great work, but it's tough making a UI, and unfortunately it's just not working for me.  I'm thinking of returning to Ubuntu with the 14.04 release, but not if it means using Unity. I have looked into the current situation, and I'm a little confused about the terms being thrown around. I have seen referens to "fallback", "flashback", and "classic", without any clear idea of which is available and what they offer.  Is there still an option to get an interface that resembles the way Gnome used to look?  Can I get an interface that looks like what I have with Mint, but with the support and features of Ubuntu? Can I get something close to that?


Where is the boot loader, such as Grub, installed generally?   When I install 12.04 along side Windows on different partitions of my disk, I encountered a choice for "Device for boot loader installation". If I understand it correctly, it is to specify where to install the boot loader Grub,  I found on the internet that it is to specify the disk that contains the partitions for the OS, not any partition on the disk. E.g. disk sda, not partition sda1, sda2.  Questions:  I wonder where the boot loader installed actually on the disk?  Is it installed on any of the existing partitions for the OSes and for personal data, or does it have its own partition, which is also visible e.g. from system monitor of Ubuntu?  Thanks and regards!


Is StackOverflow converging towards "done"?

During the daytimes I visit StackOverflow, I often have the feeling that the gross of the questions is unseen, unvoted on or downvoted.  I see a lot of low-quality-, no-reasearch-kind of questions.  It feels like popular question only come up rarely, and that StackExchange box on the right only seldomly shows StackOverflow questions.  Does StackOverflow converge towards the state of "Done"?    Aside: Was that the business reason why new languages are explored now?    I was writing up my own theory as an answer, but then the question got closed:  Here is my new theory:  StackOverflow is on a decline. During european daytimes at least, a lot of questions are closed (because of quality, duplication or lack of research). That decline roots in that the big questions of the past years are answered now.  A majority of good question is now very specialist, with minor audiences.  However. Technology and reasearch advance faster and faster. Even though the not-so-good or specialist questions now hide the big questions by their sheer number, sooner or later the number of new and pristine questions will exponentially rise.   We will be travelling towards the technological singularity.


Align vertically unknown-height floating divs inside a div

I have been trying to adapt the basic responsive layout (out of w3schools) with a "row" div containing various "element" divs that may display side by side or one on top of the other depending on the media. Yet, my divs contain a variable amount of text and they are displayed top-aligned. I read everything I could find on StackOverflow and elsewhere but could not figure out how to make the least number of changes (with the least impact on the rest of the design) and get them aligned vertically in the middle or at the bottom.  Below is a sample starting point, removing everything unnecessary from  example. Could the three rectangle be middle-aligned or bottom-aligned without changing everything?    * {   box-sizing: border-box; }  .column {   float: left;   width: 33.33%;   padding: 10px; }  .row:after {   content: "";   display: table;   clear: both; }

The quick brown fox jumps over the lazy dog The quick brown fox jumps over the lazy dog The quick brown fox jumps over the lazy dog

Column

The quick brown fox jumps over the lazy dog

     I am pretty much a newbie, but whatever I read seems to be very much incompatible with the above layout strategy and to have plenty of side effects on the visual appearance, on the responsiveness, etc.


Can I create extension for mapd database?

I want to create extension for mapd database to access from geoserver.  so I want to make sure mapd support GeoServer or not?


Creating Ellipse in WGS84 with metric parameters

I have points in WGS84 (x,y), radiuses in meters (rx, ry), rotation angle in degrees. I would like to create a new WGS84 geometry.  I've tried this but the major/minor distances seem to be off by a few hundred meters in some cases.   Ellipse (x,y,rx,ry,rotation,#of segments in 1/4 of ellipse)  SELECT transform(  translate(   rotate(    scale(     buffer(      transform(setsrid(makepoint(0,0),4326),3395),      1,    $6),   $3,$4),  $5), x(transform(setsrid(makepoint($1,$2),4326),3395)), y(transform(setsrid(makepoint($1,$2),4326),3395))),4326)


Number of zeroes of solution to $y''(x)+e^{x^2}y(x)=0$ in $[0,3π]$

The question is to investigate the number of zeroes of $y''(x)+e^{x^2}y(x)=0$ in $[0,3π]$.  Solving this ODE would not be an easy task as one has to use the power series solution and then investigating the zeroes of the solution will require more analysis. I thought it to compare this ODE with the standard $y''(x)+y(x)=0$ whose solution has three or four zeroes in the interval $[0,3π]$.  Since the coefficient of $y(x)$ is $e^{x^2}\ge 1$ for $x\in [0,3π]$ so the solution of given ODE must have atleast three zeroes in $[0,3π]$. However, what  I thought was in the lights of Sturm-Comparison theorem so I am not sure.  Am I correct to interpret this?


Cocktail of chemical compounds robustly promoting cell reprogramming protects liver against acute injury

I would like to edit this journal article title to make it sound better Which one is the best option? Cocktail of chemical compounds which robustly promotes cell reprogramming protects liver against acute injury or Cocktail of chemical compounds that robustly promotes cell reprogramming protects liver against acute injury Also, do I use 'promote' or 'promotes'?


How can I import Python file from other file?

I've checked sys.path variable and one of its values is /app, so that's ok. I've run os.listdir() to verify the directory tree is as I'm assuming, and it is like that: Directory tree: -app:    -dirA:       -subdirA:          -subsubdirA:             -fileA.py    -dirB:       -subdirB:          -fileB.py I want to import fileA from fileB. I've tried adding _ init _.py file in all directories, and doing import dirA.subdirA.subsubdirA.fileA as fileA, but it doesn't work. I've also tried adding fileAs path to sys.path like sys.path.insert(0, "/app/dirA/subdirA/subsubdirA"), and then doing import fileA from fileB.


Why am I automatically logged back in after I've already logged out?

I'm trying to log out of Stack Overflow.  I can't.  It used to work when I had MyOpenId credentials.  But I just created a new Stack Exchange account.  I can choose the down arrow next to my name, and choosing "log out", then clicking the "Log out" button.  Stack overflow then says I'm logged out.  But if I choose to log in again, when I choose to log in via a Stack Exchange account I just get a "log in" button that works without asking me my username or password.  How the flip do I really log out?  If it matters, I'm using Chrome.  (This may or may not be a dupe of  - it sounds similar).  Edited to add:  This is NOT a dupe of  because I'm not using an external OAuth provider, I'm using Stack Exchange's own account system.  And AFAICT there's no way to log out of Stack Exchange's own account system?


In ESB, did Vader sense Leia instead of Luke when he was chasing the Falcon?

In ESB, at the end of Hoth's attack, Vader saw the Falcon take off.  He's looking for Luke Skywalker. For him, Luke is on the ship, according to this:     "Our pursuit ships have sighted the Millennium Falcon, my lord. It has   entered an asteroid field.” “Asteroids don’t concern me, Admiral,”   Vader said as he slowly clenched his fist. “I want that ship, not   excuses. How long until you will have Skywalker and the others in the   Millennium Falcon?”   (ESB - Novelisation)  Why is he certain that Luke is onboard of the Falcon? He hasn't seen him...  Has he sensed, via the Force, that a Skywalker was onboard?  If so, was it not Luke, but rather Leia?


Create a new layer from overlap between two layers?

I'm new to desktop GIS, and will try to ask while lacking the proper terms from the GIS lingo:  If QGIS was like Photoshop I would like to make a selection from one layer, and then match that selection to another layer to get the overlap between the two and create a new layer from this overlap.  Formulated in another way:  I want to select all land from each of the Norwegian municipalities. In the shapefile I have (you can download it here: ) municipality borders are found as "N5000_AdministrativGrense" (just the borders) and "N5000_AdministrativFlate" (borders and the land within each municipality). This data (borders and land per municipality) is too administrative - it includes ocean and we have a lot of fjords in Norway. I need the landmass minus ocean.  The landmass is found in the layer "N5000_ArealdekkeFlate" - or so it looks to a novice at least.   So - I want to find the intersection between the landmass (only land, no ocean) and municipality borders and make a new layer that is all municipalities without ocean.  I'm on a mac with QGIS as my installed tool. All tips, pointers and help is much appreciated.


English doesn't apper as the display language in Windows 8. No download option available

I installed Windows 8 Pro edition Spanish version and I'd like to have English as the display language for Windows.  I follow the steps detailed in the solution but the option "Windows display language: Available for download" doesn't appear next to the English language as it does with Spanish.  I guess that English language is pre-installed with Windows 8 Pro.  It happens the same with the rest of the languages. You only can add the language as an input method and can't download it.  Maybe I can't set English language as the Display Language due to the license type of my Windows 8 SKU?


Apt-get 403 Forbidden, but accessible in the browser

I've noticed that running apt-get update recently has resulted in quite a few ppa's returning "403 Forbidden".  In and effort to clean them up I had a look:  W: Failed to fetch http://ppa.launchpad.net/gnome3-team/gnome3/ubuntu/dists/raring/main/binary-amd64/Packages  403  Forbidden  W: Failed to fetch http://ppa.launchpad.net/gnome3-team/gnome3/ubuntu/dists/raring/main/binary-i386/Packages  403  Forbidden  E: Some index files failed to download. They have been ignored, or old ones used instead.   The strange things is, if I copy these URLs into my browser I can access the files just fine.  Why would apt-get report "403 Forbidden" if they're still accessible?  I tried re-adding the ppa through add-apt-repository which downloads the signing key again, and it still reported "403 Forbidden".


Is there anything I can do about someone who has pointed their domain at my ip?

This is kind of a weird request. For some reason whoever owns safeandbuy.com has pointed their domain at my IP address. The reason it's a problem is that I'm having all kinds of crawlers that are trying to crawl my site with that domain name.   Is there anything I can do about this?


Why is $1^{\infty}$ considered to be an indeterminate form

From : In calculus and other branches of mathematical analysis, an indeterminate form is an algebraic expression obtained in the context of limits. Limits involving algebraic operations are often performed by replacing subexpressions by their limits; if the expression obtained after this substitution does not give enough information to determine the original limit, it is known as an indeterminate form.    The indeterminate forms include $0^{0},\frac{0}{0},(\infty - \infty),1^{\infty}, \ \text{etc}\cdots$   My question is can anyone give me a nice explanation of why $1^{\infty}$ is considered to be an indeterminate form? Because, i don't see any justification of this fact. I am still perplexed.


Who are these characters referenced in "Transformers: Age of Extinction"?

Who are the       "creators"   referenced in Transformers: Age of Extinction? Is there any such reference in the cartoon series, or comics?


Do virtual particles actually physically exist?

I have heard  pop in and out of existence all the time, most notable being the pairs that pop out beside black holes and while one gets pulled away. But wouldn't this actually violate the conservation of energy?


Can I decide to lower my Initiative after rolling it in order to permanently change my position in the sequence of turns?

The current question is in some sense a follow-up to the following one:    The answer to that question is no. The only means to acting at a different turn in the round than that which was assigned to you via Initiative rolls is the Ready action.  However, what if I decide right at the beginning of the encounter that I want to change the position of my turn permanently? Can I choose to lower my initiative? Is there any other way to achieve a similar effect?


On Windows 7, I have to check a box, at the bottom of the Processes tab in Windows Task Manager and I find a list of 14 svchost.exe Windows Services running. It says Host Process for Windows Service. Does that mean it is okay or could it be anything?  I am not a Geek or Super user so this tells me nothing. So I right click on one of them and choose, Go to Services. It flips me over to the Services tab and 5 Services are running. They are all local services and all running. (WidiServiceHost, fpdHost, khmsvc, netprofm and nsi) Daugh. I think it is really Windows but still don't know for sure. How do I know what's what?  So I go back to the Service, right click and choose, Create Dump file. Go to Windows Explorer, MyUserName/App Data/Temp and find the file svchost.DMP file, 53,128 KB, but windows cannot open it. Try Open Office. No Joy. Go to the web Find instructions.  Tired out. Giving up. Can you make it easier? How do I know when a service is good, bad or ugly?


What are the roots of $ x^{2} = 2^{x} $? I drew the graphs and found $ x = 2 $ and $ x = 4 $, and there is one other root in $ [-1,0] $. Can anyone describe an algebraic method to obtain all roots?


I am trying to create directories 1-15 in single line mkdir with a script. The complete working command is: mkdir testdir{1..15} This command create 15 directories: testdir1, testdir2, testdir3..    I defined: Directory name, range-start and range-end as variables. Instead of getting 15 directories on the given path (testdir1, testdir2, ..) I get 1 directory named: testdir{1..15}    What am I doing wrong ?    #!/bin/bash  path=/export/lofi range_start=1 range_end=15 dirname=testdir cd "$path" echo "Current directory: `pwd`" echo "Creating directories from $range_start - $range_end" mkdir $dirname{$range_start..$range_end} echo $dirname{$range_start..$range_end}   I tried:    mkdir $dirname{$range_start..$range_end} mkdir '$dirname{$range_start..$range_end}' mkdir $dirname`{`$range_start..$range_end`}` mkdir "$dirname{$range_start..$range_end}"


Coming from a Java background, I've got used to creating an object and using it's methods in main class by referencing the object and it's method, for example:  object.objectMethod();   Having different classes with identical-named methods wasn't an issue, but now I'm doing a project in Arduino which is pretty much C++. A  on using classes in Arduino suggests using class name and double colons in .cpp file before every single method. A bit of googling led me to believe that this is called a namespace. Further googling on namespaces in C++ yielded various options of use of namespaces, but none of them were like the one in the Arduino tutorial and that got me puzzled.  My question: what is the appropriate use of namespaces and if using it as in linked tutorial is a good practice?


How can I prove the following statement?  $$\binom{n}{0} ^2 + \binom{n}{1} ^2 + \binom{n}{2} ^2 + ... + \binom{n}{n} ^2 = \binom{2n}{n}$$  I know that:  $$\sum_{k = 0}^{n} \binom{n}{k} = 2^n$$  But I don't see how I could use it to prove the given problem.


I am trying to remove the following extensions from chrome but they come back every time I delete them. Everytime they have new name. Look like its virus or something. At the start there is a popup window as well. I tried to install kaspersky as well but its not catching this. Can someone help what should I do?


Normality of residuals vs sample data; what about t-tests?

An addition to the common confusion about normality testing in inferential statistics for general linear models:  I understand the assumption of normality refers to the residuals in ANOVA and regression models, but what about t-tests?  Calculation of the t-statistic uses standard deviation as a measure of dispersion, rather than sums of squares for the F-statistic in ANOVA and regression. If I understand correctly, it is because of this that there is an assumption that the samples are normally distributed (i.e. the sample standard deviation provides an accurate estimate of the population standard deviation). Is this right?  What do you do if the statistical population of the dependent variable is not distributed normally (thus samples are unlikely to be normally distributed)? Is this where transformations fit in?


Sun’s corona is so much hotter than Chromosphere

What makes Sun’s corona so hot? I tried to google it but can’t find satisfactory answer.


How can I determine the installed edition of Windows 8 if the OS does not boot up?

I have a drive that I cannot boot, but it has an installation of Windows 8 on it. I need to know what type of Windows 8 it has. Is there a folder or file I can look at that might give me a clue as to the flavor of 8 (Standard, Pro, Enterprise, or RT) I need to use for a recovery installation?   Since the OS is not booting even in safe mode I can only use command prompt. Thanks.


How do you get assembler output from C/C++ source in gcc?

How does one do this?  If I want to analyze how something is getting compiled, how would I get the emitted assembly code?


Single service account running all SQL Servers

Is there any negative performance impact for using the same service account and agent account to run SQL Server and SQL Agent respectively for all SQL server instances running at a small company of say 35 servers? The biggest database is 0.5 GB. any suggestions are welcome. Thank you.


Using a url variable, is there a way to display a draft post when not logged in

Is there a method of displaying a post that is a draft when not logged in?  For example I have created a mailer template for my news...  <?php if ( isset($_GET["mailer"]) ) get_template_part( 'mailers/template', 'news' ); else { get_header(); ?>      <!-- WEB TEMPLATE -->  <?php get_footer(); } ?>   This is on my single-news.php template.  As you can see my news mailer template is pulled in when I use this variable... ?mailer   http://www.example.com/my-news-reports/?mailer   But I would like to be able to still use the mailer template even when in draft mode.  Is this possible with adding a variable like this.. ?mailer&draft=true  I understand the 404 template is retrieved, and this may cause issues. Just wondering if there was a method I could adopt to get round this draft issue.  Thanks


Will an object always fall at an infinite speed in a black hole?

Most of you if not everybody will agree that the stronger the gravitational pull, the faster an object will fall. For example, on a planet with 50 times the gravity of Earth, any object will hit the ground on that planet much quicker than it would on Earth. So taking all of these into the equation, does it mean that at a blackhole, an object will fall at an infinite speed because of the infinitely strong gravitational pull of the blackhole?


How to integrate $\int \frac{1}{\sin^4x + \cos^4 x} \,dx$?

How to integrate    $$\int \frac{1}{\sin^4x + \cos^4 x} \,dx$$    I tried the following approach: $$\int \frac{1}{\sin^4x + \cos^4 x} \,dx = \int \frac{1}{\sin^4x + (1-\sin^2x)^2} \,dx = \int \frac{1}{\sin^4x + 1- 2\sin^2x + \sin^4x} \,dx \\ = \frac{1}{2}\int \frac{1}{\sin^4x - \sin^2x + \frac{1}{2}} \,dx = \frac{1}{2}\int \frac{1}{(\sin^2x - \frac{1}{2})^2 + \frac{1}{4}} \,dx$$  The substitution $t = \tan\frac{x}{2}$ yields 4th degree polynomials and a $\sin$ substitution would produce polynomials and expressions with square roots while Wolfram Alpha's solution doesn't look that complicated. Another approach: $\sin^4x + \cos^4 x = (\sin^2 x + \cos^2x)(\sin^2 x + \cos^2 x) - 2\sin^2 x\cos^2 x = 1 - 2\sin^2 x\cos^2 x  = (1-\sqrt2\sin x \cos x)(1+\sqrt2\sin x \cos x)$  and then I tried substituting: $t = \sin x \cos x$ and got  $$\int\frac{t\,dt}{2(1-2t^2)\sqrt{1-4t^2}}$$  Another way would maybe be to make two integrals: $$\int \frac{1}{\sin^4x + \cos^4 x} \,dx = \int \frac{1}{(1-\sqrt2\sin x \cos x)(1+\sqrt2\sin x \cos x)} \,dx = \\ \frac{1}{2}\int \frac{1}{1-\sqrt2\sin x \cos x} \,dx +  \frac{1}{2}\int\frac{1}{1+\sqrt2\sin x \cos x} \,dx$$   ... and again I tried $t = \tan\frac{x}{2}$ (4th degree polynomial) and $t=\sqrt2 \sin x \cos x$ and I get $\frac{\sqrt 2}{2} \int \frac{\,dt}{(1-t)\sqrt{1-2t^2}}$ for the first one.  Any hints?


How to give feedback to an immutable page at wiki.ubuntu.com

I want to give feedback to this page since I am missing something.    I have a login for this site, but since the page is immutable, I can't change it.  How can I give feedback if I am missing something an a wiki.ubuntu.com page?


Empty line (in code) before enumerate environment

I like my code to look like this:  \documentclass{article} \begin{document}  \begin{enumerate}   \item test text    \begin{enumerate}     \item 1     \item 2     \item 3     \item 4     \item 5   \end{enumerate} \end{enumerate}  \end{document}   For the sake of readability I like to put a blank line before a new environment starts. In the particular case I'm considering, the blank line adds some vertical space between the item from the first level enumerate and the first item from the second level enumerate.  So my question is: is there a best practice to format code related to blank lines before environments start? Should I avoid it? Should I comment out the blank line?  Clarification:  I'm talking about the vertical space between "test text" and "1". But, I'm not asking for a way to remove the extra space added by the blank like, I already know how to do that. My reasoning is the following:  Since adding a blank like before a new enumerate adds vertical space, it means that that blank line is meaningful for TeX. Since it is meaningful for TeX, is it OK to use it for the mere purpose of formatting code or should I avoid it?


Where can I find tables of common shutter speed and aperture values?

I'm working on image processing software (mind that I'm a programmer and when talking about photography, I'm "tabula almost rasa").  In this software, I'm using a RAW decoder that returns a data representation of the image that I can work on. With it I also get a lot of metadata. I need to use and display some of these metadata values, but the problem is I need to display them rounded to common values. For example the data I get from the image are:  Aperture: 14.05 (not sure about rounding here)  ISO: 200 (nothing wrong here :))  shutter: 0.0101316 (approx. 1/98, which means it should be rounded to 1/100 )  Now what I need are some "complete" (as complete as possible) tables for common aperture and shutter speed values.  (You know, when the shutter speed is 1/99, you automatically round it to 1/100, when it's 1/7800 you round it to 1/8000.  I don't care about stops and other things since I can't so anything about them, I only need a table of shutter speeds/apertures, so I can round the values I get to them).  Something like:  when photographers talk, the shutter speeds they expect are:  15 8 4 2 1 1/2 1/ 1/8 1/15 1/30 1/50 1/60 1/100 ...... 1/3000....1/8000  common apertures are:  ...1 2 3 4 5 6.... 14 16....


Is the energy carried by gravitational radiation a viable candidate for $\Lambda$ / dark energy?


I want to move all my villagers back to the middle of my town. I'm trying to work with the /tp command, but almost every time it says Entity not found. /tp @e[type=minecraft:villager,dx=300,dy=300,dz=300] @p  /tp @e[type=minecraft:villager,distance=200] @p  The only time it worked was when I did this: /tp @e[type=minecraft:sheep] @p  and it teleported like a hundred sheep into me. Is there a reason the above ones wouldn't work? 1.14.4, using LAN mode with one other person


Prevent GRUB from showing up by default?

Whenever I boot on Ubuntu, I see the entire GRUB menu by default. Is there a way I could make it simply auto-boot if uninterrupted within X seconds? I remember that this was the case on previous releases of Ubuntu, it would only show the GRUB menu if you held down a button during the boot.   How can I make GRUB do this by default and just get on with the boot process?


Time dilation of a body A with respect to B

Let there be two bodies a and b. Let a be on Earth and b in space with velocity $(√3/2)c$. Then let the time interval which has passed (on the earth) be twice that of the time interval of which passed in space for b, (i.e. the time for b is dilated for body a).  Does b also feel that the time interval which it passed with a spaceship in space is twice that of the time interval of a which passed on the earth? I ask this because for b relative to it, a is also moving with velocity $(√3/2)c$.


Clip raster with another raster (by extent) in Python

I'm trying to do raster algebra with two rasters, but when I transform the rasters to array I can't do the operation because the files do not have the same extent  example:  from osgeo import gdal import numpy as np  IMG1 = gdal.Open('C:/IMG1.TIF') IMG2 = gdal.Open('C:/IMG2.TIF')  img1 = IMG1.ReadAsArray() img2 = IMG2.ReadAsArray()  img1+img2 >>>>> ValueError: operands could not be broadcast together with shapes (5353,3352) (5548,3232)    So.. if I see the gt of every img show that img1 and img2 have the same size of the pixel (100) but different extent  g1 = IMG1.GetGeoTransform() gt1 >>>>> (482084.999999999, 100.0, 0.0, 5652715.00001374, 0.0, -100.0) g2 = IMG2.GetGeoTransform() gt2 >>>>> (475184.999999999, 100.0, 0.0, 5643715.00001535, 0.0, -100.0)   So.. I used this operation in order to get the intersect extent.. but I don't know how to apply  r1 = [gt1[0], gt1[3],gt1[0] + (gt1[1] * IMG1.RasterXSize), gt1[3] + (gt1[5] * IMG1.RasterYSize)] r2 = [gt2[0], gt2[3],gt2[0] + (gt2[1] * IMG2.RasterXSize), gt2[3] + (gt2[5] * IMG2.RasterYSize)] intersection = [max(r1[0], r2[0]), min(r1[1], r2[1]), min(r1[2], r2[2]), max(r1[3], r2[3])]


What is the current element in Javascript?

How can I find out what the element is that a <script> sits in? As an example, let's take this  <div>  <script type="text/javascript">   var time = new Date(), hrs = time.getHours(), min = time.getMinutes();   document.write('It is '+hrs+":"+(min<10?'0':'')+min);  </script> </div>   Then if I want to change this to something more modern, how can I find out what element we're in? So I want to write, for instance in jQuery  $(thisdiv).html('It is '+hrs+":"+(min<10?'0':'')+min);   but how do I get thisdiv? Yes, I know, I can put an ID on it, but I have the feeling that wouldn't be necessary. The browser knows where we are, otherwise it couldn't even do the document.write!    So, suggestions? I searched, but couldn't find it. Is it so simple that I'm overlooking the obvious?


How do I diff the output of multiple commands? vimdiff can support up to four files, but diff itself seems to support exactly two files.  Is it directly possible with some variant of diff, or do I have to save the output of all commands to temporary files, pick one and diff the remainder with it?    Context:  I have to check the output of a certain command on multiple servers and see if they all agree. For the moment, just reporting if any differences are found seems good, but if possible, I'd like to be able to say: X% servers agree with each other, Y% with each other; or that server Z is the odd one.  I have a four-way multi-master LDAP setup, and I want to verify that the ContextCSN values for all four agree with each other.  So now I do:  #! /bin/bash  for i in {1..4}.ldap  do      ldapsearch -x -LLL -H ldap://$i -s base -b dc=example,dc=com contextCSN > $i.csn;  done set -e  for i in {2..4} do     diff -q 1.csn $i.csn done   And check the error code of the script. Are there better tools for this?  Any tools that can be used on Ubuntu 14.04 welcome.


Use other environment variables in PATH definition

I've been wondering if there is a way to set the PATH system variable using other system variables. For example my /etc/environment currently looks like  PATH="........other stuff........ :$SCALA_HOME/bin" SCALA_HOME="/usr/lib/scala/scala-2.11.4"   But I can't get the path to actually use the SCALA_HOME variable I defined.  When I type 'scala' into the terminal it isn't recognized as a command.  I know I could just add the actual value of SCALA_HOME to the path like this...  PATH="........other stuff........ :/usr/lib/scala/scala-2.11.4/bin"   But I feel like this is repetitive and there should be a way to do it the way I was trying.  Anyone know how to do this?


How can I swap two specific items using a command block?

I'm making a map where you have to craft items to destroy more items, and so on. You need to craft this Stone Pickaxe and you are in Adventure Mode so it can't break anything. I want to swap it with another Stone Pickaxe which can actually destroy blocks. I know the /give <item>{CanDestroy:["<block>"]} 1.  Please help me swap items.


Driver error when trying to install Steam on 16.10

I downloaded the Steam .deb file from the official website, but after installing it with:  sudo dpkg -i steam_latest.deb   I have found that upon trying to launch it with:  steam   I now get this error:  Running Steam on ubuntu 16.10 64-bit STEAM_RUNTIME is enabled automatically /bin/bash: /home/<username>/.local/share/Steam/ubuntu12_32/steam-runtime/amd64/lib/x86_64-linux-gnu/libtinfo.so.5: no version information available (required by /bin/bash) grep: symbol lookup error: grep: undefined symbol: pcre_jit_stack_alloc grep: symbol lookup error: grep: undefined symbol: pcre_jit_stack_alloc grep: symbol lookup error: grep: undefined symbol: pcre_jit_stack_alloc awk: /home/<username>/.local/share/Steam/ubuntu12_32/steam-runtime/amd64/lib/x86_64-linux-gnu/libtinfo.so.5: no version information available (required by /lib/x86_64-linux-gnu/libreadline.so.7) Installing breakpad exception handler for appid(steam)/version(1476379980) libGL error: unable to load driver: i965_dri.so libGL error: driver pointer missing libGL error: failed to load driver: i965 libGL error: unable to load driver: i965_dri.so libGL error: driver pointer missing libGL error: failed to load driver: i965 libGL error: unable to load driver: swrast_dri.so libGL error: failed to load driver: swrast   Initially it asked me to just install some dependencies (the drivers it is complaining about now I guess) and it installed Steam with the usual window and everything but then told me that there as a fatal error and that it had to close. This was because I didn't install the dependencies as it launched an untrusted window asking for my password, however after the installation of Steam I did install the dependencies it requested.  However now it just gives me the error above, I have tried purging it and reinstalling it many times but now it doesn't even try to download Steam in the usual way with the little Steam window, now it just gives me that error.  I am running Ubuntu GNOME 16.10 with GNOME 3.22, what do I do to fix the problem and be able to install and launch Steam successfully?  Also, I would prefer to install it from the official source rather than from the universe repository as I don't know how well this is maintained.


I'll be working on creating a apex schedule class and I just need a pointer to start is that possible if you can have a working small sample where I can understand how the mechanics work and I have googled but not find what exactly I want and also I looked at the salesforce site


How do I block cookies just on Medium.com?

Pardon the interruption.  Medium is tracking me and I don't care about Medium. How can I block their cookies in Safari?


How can I rotate matrix   |3 4 5 6 8| |5 4 3 2 6| |3 3 7 8 9|   to    |8 6 9|             |6 2 8| |5 3 7| |4 4 3| |3 5 3|   Because all algorithms I've seen was for N*N matrix.


List of functions with $f(x)=\dfrac{d\,f(x)}{dx}$ like $f(x)=0$ or $f(x)=e^x$

We know for $f(x)=0$ and $f(x)=e^x$ the function is same as its derivative. I was wondering if there are any other such functions and how do we go about finding it?


We see things ON / IN / AT the internet?

Which of the following prepositions is correct when talking about seeing something on internet?      You can see it ON / IN / AT the internet.


still doesn't have binaries for 19.10 The other option is to . I've downloaded the source of . Installed needed packages written . plus gettext said . so the needed packages was:    sudo apt install qtbase5-dev-tools qtbase5-dev libqt5opengl5-dev qtchooser libglu1-mesa-dev libpng-dev libjpeg-dev libtheora-dev liblua5.3-dev build-essential gettext   the INSTALL says how to build. while desktop of Ubuntu is gnome we need this instructions (maybe you need to do autoreconf --install before starting the first line.):  autoreconf -f ./configure --with-gnome    #says --with-INTERFACE make make install   the first line done successfully. but in configure step. we face the needed packages:  No package 'libgnomeui-2.0' found No package 'gtk+-2.0' found No package 'gtkglext-1.0' found   but I do not know how to install these packages. I can not find them. How can I install these packages and finalize installation of Celesta?


Is it possible to assign a ringtone to a group of contacts?

Without individually setting the ringtone for each contact in that group.   Maybe there are other apps that manage contacts and have this feature.   Basically, I want my iPhone to ring the same when contacts from a group call.


Is it possible to gain admission to an engineering master's program without an undergraduate engineering degree?

I tried to search for this and could not find it. This is my first stack exchange post so go easy please.  Here is my situation.  I have an undergraduate degree in economics from a top tier economics program, and a very top tier university in general, with a GPA above 3.5. After working in economics research at a highly respected institution for 2 years after graduating, I've realized I want to pursue a different career. The work I do is highly quantitative and involves some computer programming using C++. I'm also pretty good with mathematical and data analysis/statistical software, and have worked multiple RA jobs as an undergraduate.  Ideally I would do something related to software engineering or electrical engineering since I'm interested in computers. My question is, to what extent is this possible? Is it possible at all? Will universities see that I don't have an undergraduate engineering degree and reject me? Do I have any sort of shot here given my background?


How to find infinite sum How to find infinite sum $$1+\dfrac13+\dfrac{1\cdot3}{3\cdot6}+\dfrac{1\cdot3\cdot5}{3\cdot6\cdot9}+\dfrac{1\cdot3\cdot5\cdot7}{3\cdot6\cdot9\cdot12}+\dots? $$   I can see that 3 cancels out after 1/3, but what next? I can't go further.


I want to enable telnet on Windows 10.  I only see a telnet client but not a telnet server.  There is a web page telling me to open server manager and do a lot of stuff.  But, I don't have a server manager.  Please help!  I want to enable telnet.


Can I have 1 hard disk for Ubuntu and another for Windows. I have to use software for both systems. I know Virtual Box can do the same thing, but it is very slow for my computer. So is it possible. If yes, how to implement? Any suggestion will be appreciated. Thank you!


Finite ring with unity has $ab=1_R\implies ba=1_R$ for $a,b\in R$

Our prof gave us the following problem as an exercise:  Suppose $(R,+,\cdot)$ is a finite ring with unity (denoted $1_R$) such that for some $a,b\in R$, we have $ab=1_R$ Show that $ba=1_R$  Here's my attempt at a proof: Proof. Let us assume that $ba\neq 1_R$ Next, we consider $S:=\{(ba)^n\mid n\in\Bbb Z^+\}\subseteq R$ Since $R$ is a finite ring, we must have that $(ba)^m=(ba)^n$ for some distinct $m,n\in\Bbb Z^+$ (wlog say $m\gt n$). Then, we have $(ba)^{m-n}=1_R$ Note that $m\gt n$, so $m-n$ is a positive integer but $m-n\neq 1$ (hence $\gt 1$) since $ba\neq 1_R$ by assumption. Now, $$(ba)^{m-n}=1_R\iff b(ab)^{m-n-1}a=1_R\iff b(1_R)^{m-n-1}a=1_R\iff ba=1_R$$ which gives us a contradiction.  Is the above proof correct? I'd like the community to proofread it. I'd also be interested in a shorter argument to prove the claim (if there is one). Thanks!


Can, could, will and would usage and difference

I see countless of people using "can", "could", "will" and "would", simply using them, mixing them up and more. I am not sure and want to be clear of the meaning, usage and difference of these words. These are a few examples: Can and could a) I can check your order and see how is the status. b) I could check your oder and see how is the status. a2) Can you give me a lift back home? b2) Could you give me a lift back home? Will and would a) I will help you with your homework tomorrow. b) I would help you with your homework tomorrow. a2) Will you refund my money? b2) Would you refund my money?


In the new interface, is there a way to search for chat rooms by name?


How come $\frac{\partial(\partial_{\beta}A_{\gamma})}{\partial(\partial_{\mu}A_{\nu})} = g_{\beta\mu}g_{\gamma\nu}$?

For context, this equation is used in the following (from Schwartz's QFT 3.44)  $$\partial_{\mu} \frac{\partial(\partial_{\beta}A_{\gamma})^2}{\partial(\partial_{\mu}A_{\nu})} = \partial_{\mu}\left[2(\partial_{\alpha}A_{\alpha})\frac{\partial(\partial_{\beta}A_{\gamma})}{\partial(\partial_{\mu}A_{\nu})} g_{\beta\gamma}\right] = \partial_{\mu}[2(\partial_{\alpha}A_{\alpha})g_{\beta\mu}g_{\gamma\nu}g_{\beta\gamma}]=2\partial_{\nu}(\partial_{\alpha}A_{\alpha}).\tag{3.44}$$  But doesn't $$\frac{\partial(\partial_{\beta}A_{\gamma})}{\partial(\partial_{\mu}A_{\nu})} = g_{\beta\mu}g_{\gamma\nu}$$ imply, for instance, that  $$\frac{\partial(\partial_0 A_3)}{\partial(\partial_0 A_3)} = g_{00}g_{33} = -1$$ instead of $=1$? Shouldn't we instead have $\frac{\partial(\partial_{\beta}A_{\gamma})}{\partial(\partial_{\mu}A_{\nu})} = \delta_{\beta\mu}\delta_{\gamma\nu}$?


Deep Q Network: Cannot reduce training error

I am trying to train a Deep Q Network () for a simple control task. The agent starts in the middle of a 1-dimensional line, at state 0.5. On each step, the agent can move left, move right, or stay put. The agent then receives a reward proportional to the absolute distance from its starting state. If the agent reaches state 0.35 or state 0.65, then the episode ends. So, effectively the agent is encouraged to move all the way to the left, or all the way to the right.  For now, I am just trying to train a deep neural network in Keras / Tensorflow, to predict the q-values of the three actions, in any given state. At each time step, actions are chosen randomly, so I am just trying to see if the network can predict the correct q-values, I am not trying to get the agent to actually solve the task. However, my network is struggling to learn the correct function.  In this first figure below, the dots represent the training data available to the network on each weight update. These are stored in the experience replay buffer in the standard q-learning algorithm. As can be seen, states further from the centre have higher q-values, as would be expected. Also, when the state is greater than 0.5, higher q-values are assigned to the "move right" action, as would be expected, and vice versa. So, it seems that the training data is valid.    In the next figure below, the predicted q-values are shown from my network. To get these values, I sampled uniformly from the range 0.35-0.65 to get the inputs, and then plotted the q-values for each action (the three coloured lines). The gradient is computed with respect to the difference between these predictions, and the training data in the first figure. So, these lines should match up to the points in the first figure. However, clearly they do not. They are predicting roughly the right values, but the shape of the lines are not consistent with the training data.    In the third figure below, I now plot the training loss for this network. So, it appears that training has converged, even though there is still significant error between the training data and the predictions. I am using mean squared error loss.    Finally, here are some details on my network itself. I use 1 layer of 16 hidden nodes, each with Relu activations, and the final layer has 3 nodes, one for each action. Although this is a simple network, it has enough capacity to learn the simple function in the first figure, from my prior experiments. I use the AdamOptimizer for optimisation, with a learning rate of 0.01, and I have also tried with a learning rate of 0.001 which also does not give the desired results. My batch size is 32. As with the standard Deep Q Network approach, I used a separate network for training the q values to the network used to predict the q values for the other states (as used in the Bellman equation).  So, I am puzzled as to what is going on. My network should be able to fit the training data, but it is not able to. I am not sure whether this is a problem with my optimisation, my network architecture, or my q learning algorithm. My intuition is that the learning rate is too low, because the predicted q values show a shape significantly different to the training q values, and so the network needs to be bumped significantly in the right direction. However, I am already using a learning rate of 0.01, which is very high.  Another thought I had is that the training error is pretty small (3 x 10^-4), and so it may not be possible to reduce this any more. Therefore, I would need to increase the size of the predicted q values (e.g. by increasing the scale of the reward), such that the absolute error is much larger, and therefore the optimiser can compute effective gradients. Does this make sense?  Any suggestions?


Importing Finder Folders to Albums in Photos app

I organize all of my photos into folders. I have years of photos organized properly by year_date_event_name. I would like to import the folders directly into the Photos app as Albums named as the folder name.   I can't seem to even find a way to import the folders as albums, let alone having the folder name used as the album name.   I'm guessing a script would be the best way to do this? Any suggestions would be greatly appreciated.


Are apostrophes needed in this phrase?     The whys and the hows   I searched for duplicate questions, but the closest I found was in regard to


Battle Cry feat daily uses and items providing a bonus to Charisma

I was wondering if bonuses to stats could affect the number of uses of certain abilities, specifically, do you get more uses of the Battle Cry feat if you got a Ioun Stone giving you +2 to Charisma?  If so, which uses get consumed first, the ones given by the bonus? What happens if after using Battle Cry, the Ioun Stone gets destroyed, making you lose the bonus?


This refers to   I need to install Java 11, so I run this command  sudo apt install openjdk-11-jre-headless   But it installed Java 10 according to:  tomsk@tomsk-Ntb:/opt/Build/Phoenicis/phoenicis-dist/src/scripts$ java -version openjdk version "10.0.2" 2018-07-17 OpenJDK Runtime Environment (build 10.0.2+13-Ubuntu-1ubuntu0.18.04.4) OpenJDK 64-Bit Server VM (build 10.0.2+13-Ubuntu-1ubuntu0.18.04.4, mixed mode)   One of devs said in that issue thread that Ubuntu provide Java 11 as Java 10:     the Java 11 package in Ubuntu does not provide Java 11 but Java 10   So how can I install true Java 11 on Ubuntu 18.04 LTS?  I would like to install it using repo or ppa, not binary.


Is there any way to redefine a class or some of its methods without using typical inheritance? For example: class third_party_library {     function buggy_function() {         return 'bad result';     }     function other_functions(){         return 'blah';     } }  What can I do to replace buggy_function()? Obviously this is what I would like to do class third_party_library redefines third_party_library{     function buggy_function() {         return 'good result';     }     function other_functions(){         return 'blah';     } }  This is my exact dilemma: I updated a third party library that breaks my code. I don't want to modify the library directly, as future updates could break the code again. I'm looking for a seamless way to replace the class method. I've found this  that says it can do it, but I'm wary as it's 4 years old. EDIT: I should have clarified that I cannot rename the class from third_party_library to magical_third_party_library or anything else because of framework limitations. For my purposes, would it be possible to just add a function to the class? I think you can do this in C# with something called a "partial class."


javascript : || double pipe operator alternative that tests undefined only

Is there any shorter notation for the following test?  (typeof x != "undefined") ? x : y;   A kind of x || y but that operates on undefined only (and not falsey values)  Something like ?? of C#


answers sometimes in test, sometimes in answer file

So this is going to sound strange, but I'm wondering if there is a clean way to do this.  By the time I have a project done, I will have written two .tex files: one with questions, and another one with solutions. For purposes of peer review, I'd like to know if there's a way for me to use \include so that if each question and solution to each respective question spans only one page, the question and solution will be paired together so that the question is first and the solution is second.  Is there a way (or a better way) to do this beside manually copying/pasting code?  MWE:  Questions:  \documentclass[12pt]{article} \usepackage[margin=2cm]{geometry} \usepackage{enumitem}  \begin{document} \begin{center} \textbf{Mock Exam} \end{center} \begin{enumerate}  \item Here's a question. \begin{enumerate}[label=(\Alph*)] \item Option A \item Option B \item Option C \item Option D \item Option E \end{enumerate} \newpage   \item Here's another question. \begin{enumerate}[label=(\Alph*)] \item Option A \item Option B \item Option C \item Option D \item Option E \end{enumerate} \end{enumerate} \end{document}   Solutions:  \documentclass[12pt]{article} \usepackage[margin=2cm]{geometry} \begin{document} \begin{center} \textbf{SOLUTION} \end{center} \begin{enumerate}  \item (A)  \vspace{0.2cm} -Some stuff telling you why the answer is (A)- \newpage  \item (C)  \vspace{0.2cm} -Some stuff telling you why the answer is (C)- \end{enumerate} \end{document}   This is the general way I have been creating MC exams and solutions in the past for the company, and it's still very early in the project, so I can change the code so that it works if necessary. It's just that I found it very time-consuming to copy-and-paste the solutions into a new file for peer review.


Is there a list of Tex primitives or LaTeX macros which can prevent pdflatex from reading or writing to files if blacklisted?

Not using --shell-escape sandboxes pdflatex to some degree. Still, it is perfectly possible for it to, for instance, open and read files, e.g. through \input or Tex primitives such as \read.   Is there a list of Tex primitives and LaTeX macros which, if blacklisted, will prevent pdflatex from reading or writing to files, and more generally will effectively sandbox it? I am especially interested in the case that the tikz or xymatrix packages are used.  Things like \def should presumably be blacklisted, as well as use of packages, and programming constructs like \if and \loop.  On a related note, even if one does not prevent file reading, if one blacklists ../, ~/, /etc/, /home/, and so on, is it possible to prevent pdflatex from leaving the working directory on a linux machine?


Formatting issues when using [tag:syntax] along with a link in the editor

I had a heck of time while editing my  question. But, I guess, I discovered a new weird problem in the editor while formatting hyperlink text next to  tag.  To illustrate this problem better, I would like to give the following examples:  Has problem with one or none white-space in between:  [meta-tag:status-planned] [details page reads:][2] [meta-tag:status-planned][details page reads:][2]     Gives weird output as:   [details page reads:]   [details page reads:]   But, its okay with two white-spaces in between:  [meta-tag:status-planned]  [details page reads:][2]   Gives the correct output as:      Something is strange here. I don't understand why do I have to insert two white-spaces instead of just one? Are the two white-spaces are mandatory when using [meta-tag:some-tag] with hyperlink text adjacent to it? Or, is it one of those  thing?  But wait, it's get even further complicated if I do like:   1. No white-spaces in between:  [meta-tag:status-planned][meta-tag:status-completed][Moderator-only Tags][3]     2. One white-space in between:  [meta-tag:status-planned] [meta-tag:status-completed] [Moderator-only Tags][3]       3. Two white-spaces in between:  [meta-tag:status-planned]  [meta-tag:status-completed]  [Moderator-only Tags][3]         They all seems to work perfectly fine. Now, thats very strange! Why would the two [meta-tag:some-tag] works like a charm with or without requiring to insert any white-spaces? Can anyone explain this in a better way. I don't want to jump on the conclusion by calling this as a bug yet, so I used  tag instead of  tag. Please share your thoughts.