What is causing null pointer exception at runtime?

My code compiles, but I get this error at runtime:  Exception in thread "main" java.lang.ExceptionInInitializerError     at GUI.<init>(GUI.java:46)     at GUI.main(GUI.java:252) Caused by: java.lang.NullPointerException     at java.util.Objects.requireNonNull(Objects.java:203)     at java.util.Arrays$ArrayList.<init>(Arrays.java:3813)     at java.util.Arrays.asList(Arrays.java:3800)     at db.<clinit>(db.java:23)     ... 2 more   This is the code causing the error:  public static String strLine; public static String[] filearray; public static List<String> list = Arrays.asList(filearray);   public static void load() throws IOException{  FileInputStream in = new FileInputStream("slist.txt"); BufferedReader br = new BufferedReader(new InputStreamReader(in));  filearray = new String[4];  while ((strLine = br.readLine()) != null) {  for (int j = 0; j < filearray.length; j++){ filearray[j] = br.readLine();  }  } in.close();   Line 46 referenced in the error:  JList stafflist = new JList(db.list.toArray());   I am trying to load a text file as an Array and add it to the JList stafflist, but I get a runtime error.


For a T-test, what would happen if one of my samples was made up of only one observation?

I must be missing something, or under-thinking what goes on with a basic T Test, but I was under the impression that if I do a T-test, and one of my samples was made up of only one observation, the test would fail.  To see if this is indeed the case, I ran some code in Python code.  I made up some numbers, where my first sample has 15 values and the second sample has only 1:    import statsmodels.api as sm print "This is the result of the T-test:" ttest = sm.stats.ttest_ind(np.array([821,823,814,815,816,817,881,891,234,354,678,765,989,435,657]), np.array([21]), alternative='larger') print "pvalue:", ttest[1], ", at alpha = 0.05, thus the result is:", ttest[1] <= 0.05   Here's the result:    This is the result of the T-test: pvalue: 2.72522964545e-08 , at alpha = 0.05, thus the result is: True   I am getting an answer saying that there is a significant difference between the two sample means.  Is this simply a bogus answer?    I was under the impression that one observation can't be assumed to belong to a normal distribution, so this assumption for a T-test itself can not be verified.  Thus the test should not be appropriate.


New 14.04 LTS install fails to boot with purple screen

I have just installed Ubuntu 14.04 and it got to the prompt which said it had finished installing and needed to be restarted. When booting it shows a purple screen then the monitor switches off after with no video response. I can boot using recovery mode, so I think it might be graphics card related.  Is it possible to edit the settings to make the normal boot use default video drivers?


Prove that if $A$ is invertible then $AA^\top$ is positive definite

I need to prove that if $A$ is a square invertible matrix then $AA^\top$ ($A$ multiply $A$ transpose) is positive definite.  I tried to prove that all the eigenvalues are positive. I know that $AA^\top$ is symmetric, and its determinant is positive, and trace is positive.   Therefore: product of eigenvalues is positive , and sum of eigenvalues is positive.  In addition $0$ is not an eigenvalue. That's what I know so far but I still cannot conclude that every eigenvalue for itself is positive. What have I missed? Thanks!


What software can I use to make 3D screenshots?

For example, I'd like a 3D image of screenshots, similar to this one:  (from WojoMarket's website) Are there any ready made software in order to do


why inode value changes when we edit in "vi" editor?

When I edit a file in "vi" editor the inode value of the file is changing. But when edited with cat command the inode value is not changing.


Prove $\mathbb Q (\sqrt2 + \sqrt3 ) = \mathbb Q (\sqrt2 , \sqrt3 )$

So correct if I am wrong, but these sets are:  $\mathbb Q (\sqrt2 + \sqrt3 )=\{a+b\sqrt2 + c\sqrt3 +d \sqrt6 : a,b,c,d \in \mathbb Q \}$  $\mathbb Q (\sqrt2 , \sqrt3 )=\{a+b\sqrt2 + c\sqrt3  : a,b,c \in \mathbb Q \}$  Was trying to see if the LHS is a subset of RHS and vise versa.  Let $A \in \mathbb Q (\sqrt2 , \sqrt3 )$ with $A=a+b\sqrt2 + c\sqrt3= a+b\sqrt2 + c\sqrt3  + d \sqrt6 - d \sqrt6 = a+b\sqrt2 + c\sqrt3  + d \sqrt6 - d \sqrt3 \sqrt2 $ but i can't really do anything after this. If you factor the root $3$ or $2$, it doesn't seem to help.


Resolving Velocity Components in Constrained Motion

I have been having some problem resolving the velocity component along the rope. My question will be clear if you read an illustration that I encountered which is very helpful in showing my doubt very clearly.  In the Fig. given below the block $'A'$ and $'B'$ are connected with an in-extensible string. The block $'A'$ can slide on a smooth horizontal surface.      My approaches to form the kinematics constraint equations:-   Approach 1:- The length $\ell$ of the string connecting the two blocks $A$ and $B$ can be written as follows $$\sqrt{{x_A}^2+h^2}+x_B+R\theta=\ell$$ On differentiating the above equation we get $$\dfrac{x_A}{\sqrt{{x_A}^2+h^2}}\cdot\dfrac{dx_A}{dt}+\dfrac{dx_B}{dt}=0\implies \dfrac{x_A}{\sqrt{{x_A}^2+h^2}}\cdot\dfrac{dx_A}{dt}=-\dfrac{dx_B}{dt}$$ As the block $A$ moves rightward $x_A$ increases while $x_B$ decreases. So, $\dfrac{dx_A}{dt}=v_A$ and $\dfrac{dx_B}{dt}=-v_B$. So, the kinematic constraint equation for velocity is as follows $$\dfrac{x_A}{\sqrt{{x_A}^2+h^2}}\cdot v_A=v_B\implies v_A\cos\alpha=v_B\ \qquad\qquad\left(\because \cos\alpha=\dfrac{x_A}{\sqrt{{x_A}^2+h^2}}\right)$$  Approach 2:-  The velocity of block $B$, $v_B$ is along the string hence there could be two possible constraints according to me as follows:- $$v_B\sec\alpha=v_A$$ or $$v_B\cos\alpha=v_A$$ Please do tell me as why $v_B\sec\alpha=v_A$ is correct and the other one is wrong.    Edit:- sammy gerbil's solution did clear it nicely, but I was being bugged about the thing in a different way. I had considered that what would have happened if the velocities in both the cases (the cases being the projection of the velocity along the rope in the direction of the movement of block $A$, and the other one being the projection of the velocity of the block $A$ along the direction of the rope) if resolved into components would affect the movement of the one, in the direction of which the velocities have been resolved.   Case 1:-   So, what I had considered in the case of the velocity along the rope being projected in the direction of the notion of the block $A$ is as follows:-  If the velocity of the rope is resolved as stated above then, in the direction of the motion of the block $A$ the projected velocity will be $v_B\cos\alpha$  and in the perpendicular direction it will be $v_B\sin\alpha$, as the block is not allowed to move in that direction, so the ground does something(yeah, the ground does something, I am not at all sure if the ground does somethuing in this case, so some clarification on this too) which doesn't let it move in the perpendicular direction. So, according to me this is a probable case too.  Case 2:-  In this case what I had considered was that if we resolve the velocity of the block $A$ along the rope and perpendicular to the rope we get that the velocity component along the rope comes out to be $v_A\cos\alpha$ and perpendicular to it comes out to be $v_A\sin\alpha$. Now, the perpendicular component changes the direction of the rope and the component along the rope produces the needed velocity along the rope to make the block $B$ move upwards. So, this case is also possible.  So, what is wrong in the 1st case that it is not the answer, but the case-2 is.


Serenity makes it clear that colonists left Earth due to overpopulation and resource deficiency. And it's referred to as Earth-that-was. But do we have any indication that Earth is actually depopulated?


I am trying to return "title" result in Ascending order. I tried with below code but ascending order was not working.   var details = DS.Tables[1].AsEnumerable()               .GroupBy(row => row["ID"])               .Select(row => row.FirstOrDefault()).Take(TopCount)               .OrderBy(row => row["title"])                .ToDictionary(row => row["ID"], row => new ObjDetails(DS.Tables[1].Columns, row));


All my Tool Options in GIMP are lost or unable to move

I have constantly had this problem with GIMP detaching my Tool Options. I always look for a solution on the internet, and usually I find one. This time, I couldn't. My screen looks like this:     I want my Tool Options and Paintbrush tab back and attached to the LEFT side of my window.  Things I have already tried:   Going under the "Windows" tab and adding them manually. They won't "click and drag" to the left. In fact, I can't even find my Paintbrush tab.  Going under the "Windows" tab and clicking "Single-Window Mode." Clicking and dragging doesn't work regardless if the tab is attached or detached.  Uninstalling GIMP completely and reinstalling it.   What is the problem here and how do I move them?


Determinant evaluation for matrix with $-1, 2, -1$ below/on/above diagonal

What is the trick for evaluating the determinant of this matrix?  $$\begin{bmatrix} 2 & -1 \\ -1 & 2 & -1 \\ & -1 & 2 & -1 \\ && -1 & 2 & -1 \\ &&& -1 & 2 & -1 \\ &&&& -1 & 2 \end{bmatrix}$$  $$%Commenting out original picture ![enter image description here][1]$$


What is the difference between these invocations of COUNT()?

can anyone please let me know difference between count(*), count(1), count(0), count('FAST')


Looking for the name of a Sci Fi book about a dystopian future earth with no medical services

So this is killing me...  I read the book some years ago.   My premise was that I do not read enough different authors, so I started picking books at random going down the alphabet.  This book was pretty far down the shelf of my library at the time, close to "Zhan".  The premise of the book was that medicine is bad, in prolonging life unnecessarily. So all medicine was banned.  Our young protagonist finds a medic bag in an old ambulance, and starts saving people. Leading to some unfortunate consequences.  It was called Dark Wing, or Night Wing, or some such.  Please help.


Is it possible to set the default size of the Empty Object? The problem is since I switched my blender scale to metric, the Empty's default size is kinda large for most times I need it.


School wanting to use ubuntu 20.04 on all student laptops and need to know if any special licensing is needed?

Our school is wanting to switch from a mix of Windows 8 laptops and Chrome OS laptops to all running Ubuntu 20.04, we got a few working and running as a test and there running amazing, what we were wondering was if we needed any special licensing as we did with the others or if we were good to go with just installing Ubuntu on the rest of them?


I’m learning Python 3.  My code   numbers = [1, 2] print( type( numbers[0] ))   outputs  <class ‘int’>   How do I print only   ‘int’   or   int


Ubuntu Server 14.04 web server not gathering data from mysql server

First of all: I am a beginner, and have only basic knowledge about linux and servers. Also, this question is kind of vague, but i hope you can help. I would be very thankful for all kinds of feedback and guidance!   I'm running Ubuntu server 14.04 LTS on a very old PC. I want to be able to host a webpage. I am hosting the same page locally using my 2010 mac mini with MAMP, and that works very well. I needed to update my mysql login details when i transferred the project to the PC, and  also imported the database. The problem is that when i try to view the page, it gets stuck at the point where it needs to access the db to find out wether or not the client is logged on. I've tried sudo /etc/init.d/mysql reload, sudo /etc/init.d/mysql restart and more, but it never seems to make much of a difference...


Is Google chrome and chromium are different browser

I have Ubuntu 12 in my PC. During installation of useful software, I was looking for browser except Firefox(which is by default browser). Through Ubuntu Software manager, I got Chromium and installed it. Its looks like Google Chrome. Is it the same as Google Chrome?  Thanks...


Create Control using loop then append name with string

does anyone knows how to append a string to a variable name?  public void editForm(DataGridView dg) {    for(int i=0; i<=dg.Columns.Count-1;i++)    {       TextBox txt=new TextBox();   //I want to append i to txt. like -->TextBox txt&i    } }   Then I'll add the textboxes created to a Form.


I have the below table and i would like to get the below result with using the COALESCE . Any help will be appreciated.    Thanks sam


Rigorous definition of differentials in the context of integrals.

When using the subsitituion rule in integration of an integral $\displaystyle \int f(x)\,\mathrm dx$, one turns the integral from the form $$\displaystyle \int f(x(t))\,\mathrm dx \quad(*)$$ into the form $$\int f(x(t))\,\frac{\mathrm dx}{\mathrm dt}\mathrm dt \quad(**)$$. This transform is usually accomplished by means of differenting the subsitution $x = x(t)$, such that $\dfrac{\mathrm dx}{\mathrm dt} = \dfrac{\mathrm d x(t)}{\mathrm dt}$. Now, at this point, one turns this into a differential form by means of magic, s.t. $\mathrm dx = \dfrac{\mathrm dx(t)}{\mathrm dt}\mathrm dt$. This now substitutes the differential term $\mathrm dx$ in the original expression $(*)$ to the one in the transformed expression $(**)$.  I'd like to learn that magic step a bit more rigorous – so that I can better understand it. It is often explained by "multiplication" of $\mathrm dt$, which do make sense, but it does not explain the nature of differentials; when is "multiplication" allowed? It seems there should be a more rigorous way of explaining it, perhaps by defining the "multiplication.  So, in what ways can differentials like $\mathrm dx$ and $\mathrm dt$ be formalized in this context? I've seen them being compared to small numbers, which often work, but can this analogy fail? (And what are the prerequisites needed to understand them?)


What is the equation for Multiple Linear Regression (through the origin)

I know the one for the one variable version... β =∑ xiyi / ∑ x2  but nobody seems to have the one for the multiple variable version is there a way to do it by hand for something like  y = β1x1 + β2x2  (no intercept)  EDIT: this is about the MULTIPLE variable model equation (MUST go through the origin)..the answer provided is the one I tried that doesn't go through the origin


Sometimes when I run a command I don't notice that I needed to run it as super user to have enough permission.  Is there a way to run the same command again but as a super user?


Maven: add external jar folder to classpath

I've simple Eclipse Web Project based on Adobe framework. Now I have to upgrade my project to a new version of framework and I wish to use Maven to manage dependencies, packaging, ecc.  The problem is that in the Adobe documentation is write that I MUST use thier own jars that are a lot (69). I see , but i'm looking for something smarter that add all 69 entries like that.  Usually, I would create an Eclipse UserLibrary and would add to Eclipse BuildPath, but in this case I don't know how to add them to maven classpath to compile and package the project properly


I'm trying to write a java program to test following code  12,8,23,6,5,17,20,9  m=2; n=0; while m<array length repeat ar[m]=ar[n]+ar[n+1]; m++; n++; End while    So this was my source code   public class Main {    public static void main(String [] args) {     int []x= {12,8,23,6,5,17,0,9};     int m=2;     int n=0;       while(m<x.length) {         x[m]=x[n]+x[n+1];         m++;         n++;          System.out.println(x);       }    } }   And it generated something like this as the output  [I@3d4eac69 [I@3d4eac69 [I@3d4eac69 [I@3d4eac69 [I@3d4eac69 [I@3d4eac69   Also this was my teacher's answer   public class Main {  public static void main(String [] args) {     int []x= {12,8,23,6,5,17,0,9};     int []y=algo(x); **//need an explanation**      } public static int[] algo(int[]ar) { **//need an explanation**      int m=2;     int n=0;     while(m<ar.length) {         ar[m]=ar[n]+ar[n+1];         m++;         n++;     }     return ar;    } }   However there is no generated output for teacher's code.However answer should be something like this 12 8 20 28 48 76 124 200 Please explain which one is the best code and how do they works.Also I have commented some lines of my teacher's code where I can't understand . Please explain them too.


Limit only one entry per day per user in sharepoint list

sharepoint 2013  I have a list where users should be able to create only one item per day (every user can create only one item per day).  Any help or suggestion how to manage this?


How to copy the rest of lines of a file to another file

I have the string xyz which is a line in file1.txt, I want to copy all the lines after xyz in file1.txt to a new file file2.txt. How can I achieve this?  I know about cat command. But how to specify the starting line?


Suppose we are given a number "$A$" which is multiple of $\phi(n)$. One can assume factorization to be hard. So you cannot find exact value of $\phi(n)$ from $A$.     Clearly using this we can crack RSA as for any encryption exponent '$e$' we will find its inverse modulo $A$ and that will also we inverse of of '$e$' modulo $\phi(n)$.  But will $A$ factor $n$ ??.  Its looks to me as a natural question on the line of thought of  equivalence of RSA and factoring


In what situations would it be more beneficial to use Newtonian Formalism vs Lagrangian Formalism?

I'm studying for an exam in Classical Mechanics, and I was curious to know when it is more appropriate to use Lagrangian vs Newtonian Formalism. I know that Lagrangian Formalism much more efficient, however in another physics class I was in, we hardly used Lagrangian formalism at all, and primarily used newtonian.


C# technique for determining if a computer is operating on battery power?

I've found a number of API's that can help determine how much charge (percentages, charge estimates, etc) - mostly in WMI  in my application, I'd like to know if the computer is currently powered by battery,  not the status of the battery.  in short, I'd like special behavior when not plugged in  is there such an API?  I'm happy with a win32 API to pinvoke if needed


Should Stack Exchange remove downvotes from default?

Would you think that Stack Exchange and other related sites should remove downvote function from their default?  If someone gives the worse answer they can provide another function to remove the bad answer. Can you suggest some functions if you're asked by Stack Exchange admin?   Does downvote imply your personality?   Do you feel really negative when we receive some downvotes?


How do I adjust the Time & Date manually via terminal (CLI) on Ubuntu 14.04?


Let $K=\Bbb Q(\sqrt[n]{a})$ where $a \in \Bbb Q^+$ and suppose $[K:\Bbb Q]=n$(i.e., $x^n-a$ is irreducible). Let $E$ be any subfield of $K$ and let $[E:\Bbb Q]=d$. Prove that $E=\Bbb Q(\sqrt[d]{a})$  Now $N_{K/F}(\sqrt[n]{a})=a\in \Bbb Q$ also I know that $N_{K/E}(\sqrt[n]{a})\in  E$. What I have observed is $K/\Bbb Q$ need not be cyclic as the $nth$ root of unity is not in $\Bbb Q$. So what to do next? I am clueless here.  Edit In the comment I got some help considering the Galois closure of $K$. The Galois closure will be $\Bbb Q(\zeta_n,\sqrt[n]{a})$ which has cyclic Galois group $\Bbb Z_n$ over $\Bbb Q(\zeta_n)$.  Now if $Gal(K(\zeta_n)/\Bbb Q)=<f> \cong \Bbb Z_n$ then $Gal(K(\zeta_n)/E(\zeta_n))=<f^d>$. So the element that will be fixed by $f^d$ is $\sqrt[n]{a}+f^d(\sqrt[n]{a})+\cdots + f^{(n/d)-1}(\sqrt[n]{a})=\sqrt[n]{a}+\zeta_n^d\sqrt[n]{a}+\cdots + \zeta_n^{(n/d)-1}\sqrt[n]{a}$. But is it $\sqrt[d]{a}$?


What is the solution for "Submitted URL not selected as canonical" in Google Search Console beta?

Google's new webmaster tools has a  section 'Index coverage'>'Excluded'>'Submitted URL not selected as canonical'.  I am getting 3 internal links in the section "Submitted URL not selected as canonical" of my website.   am not sure why these internal links are showing up there.  I had updated canonical tags for these 3 links.  (I am not sharing links cause may be my account marked as spam)   has some information about it, but doesn't say how to fix it:     Submitted URL not selected as canonical: The URL is one of a set of duplicate URLs without an explicitly marked . You explicitly asked this URL to be indexed, but because it is a duplicate, and Google thinks that another URL is a better candidate for canonical, Google did not index this URL. Instead, we indexed the canonical that we selected. The difference between this status and "Google chose different canonical than user" is that, in this case, you explicitly requested indexing.


I have a little Sony VAIO P series computer on which is installed Ubuntu 15.10 running LXDE. I've found that all audio played on the device is choppy, everything from MP4 videos played on VLC, to Skype, to Festival, is choppy. Here is a sound recording to illustrate:    From aplay -l, I can see that the hardware playback device is HDA Intel MID ALC275. What could be going wrong and how could I try to fix it?


How to quickly change multiple colors in the same text area?

As shown in the following image, how can I change the color of "Ms" or "Mr" in one go?  Is there any existing function that can be used or is it possible to script?


I need to find angle x in this isosceles triangle(20-80-80), by using pure geometry, if i can say so. If my calculations are correct (i tried another approach) answer should be 30, but there should be 'easy' way to find this. Also i found many  exercises which are very similar to mine but yet different.


Render Border's related check boxes - How do they work?

Render Border,    is a great little function for reducing render time while experimenting, but what does the 'Render Border' check box in the Properties >View panel do - apart from turning off the red border when un-checked? (there is no Manual reference to this)    Also, after setting a Render Border, in the Tool Shelf >Set Render Border panel, there is a 'Camera Only' check box:    I have tried many different combinations of these with renders, and the result is… confusion! Can someone please clarify this for me?


Change bash shell to look like the one on heroku demo

I am in love with the bash shell look and feel show in the intro video of heroku. Anyone has got an idea how I can implement this kind of bash look :


How weatherproof is an average modern lens?

I recently bought the Panasonic GH4, which is weather-sealed. I also got the 14-140mm lens that Panasonic makes for it (I believe it's the first version and they have a new version -  mine is .  So I know I'm fine to use the GH4 out in some rain, or that kind of thing - I'm not sure exactly HOW much weather it'll take, but it'll obviously stand up to some - but I have no clue how it'd stand up to weather. Obviously it has electronics for the focusing/OIS/etc in it, and it doesn't specifically say it's weather protected, although someone mentioned in an Amazon review that they dropped it in snow and left it overnight and it was fine - but do I trust them??  The electronics are what scare me. I plan to use some of my older, fully manual lenses (or maybe some new Rokinon ones) and mostly use them in bad weather, which I think is ok (?), but does anyone know about newer lenses like the one mentioned?


Commas and Semicolons with Nonrestrictive Clauses

If I have one brother named Frank, one sister named Danielle, and one wife named Theresa, is the following sentence punctuated correctly with the commas and semicolons? Please, just yes or no — minus the extraneous commentary or questions like "Why are you writing it like that?" Could we please just answer the questions directly?  My brother, Frank; my sister, Danielle; and my wife, Theresa, attended the meeting at Town Hall.


How to implement dynamic background music?

Assumption 1: As a game's story progresses, dynamic background music is often used to enhance the player's immersion.  Assumption 2: Background music is probably always streamed due to memory limitation and performance.  What do I need to consider when I'm checking the feasibility of having dynamic(ally changing, adapting) background music? For example when a boss enemy appears the game should not just replace the "wandering music" to "boss combat", it should rather somehow cross-fade the two music scores as it starts playing the new music.  Is it usually possible to stream multiple sounds in parallel? I'm using LibGDX, where -- as far as I'm aware -- only a single streaming music instance can be played at a time, so how can I have such music with this framework?  Do I suspect correctly if I also need to separate a dynamic music into parts like "intro", "loopable part", "loopable part near the climax", "outro", etc., and when a part ends have a music manager code decide which part should be (re)started?  I'm more interested in understanding the theory instead of the actual implementation of the code.


Is Harry Potter part of the Dumbledore family?

As per Fantastic Beasts: The Crimes of Grindelwald, a Phoenix would come to any Dumbledore who is in trouble/need.  In Harry Potter and the Chamber of Secrets, Phoenix arrives to help Harry in the Chamber of Secrets.  Can we conclude that Harry Potter was related to Dumbledore family in some way or the other?


Confidence interval for shift parameter of a shifted exponential distribution

Define $T = \theta + X$, where $X \sim \textrm{Exp}(\lambda)$, and $\theta$ is a constant.  I would like to compute a confidence interval for $\theta$ from observations $t_1, \ldots, t_n$ drawn from $T$. If you like, I can observe $\theta$ plus noise that follows an exponential distribution.  I can see that a maximum likelihood estimate $\hat{\theta}$ of $\theta$ is $\min\{t_1, \ldots, t_n\}$: the likelihood is $0$ when $\hat{\theta} > t_i$ for any $i$, and the log-likelihood for $\hat{\theta} \leq \min\{t_1, \ldots, t_n\}$ is given by  $$ \log(\lambda) + \sum_{i = 1}^n -\lambda (t_i - \hat{\theta})  = \log(\lambda) + \lambda n \hat{\theta} - \lambda \sum_{i=1}^n t_i $$  which increases as $\hat{\theta}$ increases regardless of $\lambda$ (given $\lambda > 0$), so the maximum likelihood estimate is $\hat{\theta} = \min\{t_1, \ldots, t_n\}$.  To build a confidence interval, $\hat{\theta}$ would be an upper bound, but I am stuck on computing a lower bound. I want to compute a value $\hat{\theta}_L$ from $t_1, \ldots, t_n$, such that $P(\theta \in [\hat{\theta}_L,\ \hat{\theta}]) = p$ for some $p \in (0, 1)$. How would I go about that?  A search brought up nothing but some literature on synchronizing clocks. Perhaps I am using the wrong terminology.


How do I expire by type in .htaccess for remote loaded Google fonts?

Is it possible to set expire by type for remote fonts or Google analytics? I'm getting this report from GTMetrix and everything I've tried isn't working. Suggestions?  There are 4 static components without a far-future expiration date. http://fonts.googleapis.com/css?family=Open+Sans:300 http://fonts.googleapis.com/css?family=Roboto&subset=latin,latin-ext http://www.google-analytics.com/ga.js http://www.google-analytics.com/analytics.js   All of my other expires are working fine.  But apparently this type of thing isn't right?  ExpiresByType application/x-font-woff "access 1 year" ExpiresByType application/font-woff "access 1 year"   What should I do?


I'm a bit confused with the meme "I'm tired of living through these historical events" referring to the traumatic experience living during a pandemic. Isn't it supposed to be "historic"?


Prevent DNS browser caching or clear browser DNS cache from the server

We have 2 servers. During maintenance on our primary server 1, we want server 2 to serve a "temporarily offline" page. We're doing this by simply creating an account for the domain on both servers and adding both nameservers to the domain registrar like so: NS1.SERVER1.COM NS2.SERVER1.COM NS1.SERVER2.COM NS2.SERVER2.COM  This works great and when server 1 goes offline, server 2 immediately serves the maintenance page. The issue is that server 2 is then cached in the browser/ISP DNS cache and even after server 1 comes back up, visitors still see the maintenance page. Is there some way to disable DNS caching on server 2 via PHP or Apache?


Good evening. Please I want to know something. Do I need travel history for Estonia? I am applying from Nigeria.


How to deal with neural networks when the data is unbalanced (but unlimited)?

If you assume that you have a plentiful/unlimited supply of training data, and you are using a neural network for classification, how do you deal with a situation in which a very high proportion of the data belongs to one class?    For example, if you are doing binary classification and 99% of data comes from one class and only 1% the other.  When you train the network using backpropagation, it normally uses the overall average error.  If you keep the data with the same skewness as it comes in, will that cause it not to learn the rarer class properly?  Another option is to discard data (presumably at random) from the more common class, until you have an equal proportion of data from each class, e.g. it is 50/50 in my binary example.  But if you balance the data like this, then the network is being trained on data that is not representative of real life.  The assumption that training data is plentiful (or unlimited) means that balancing the data need not reduce the size of the training set.  If extreme skewness is inadvisable, is there a threshold at which this occurs, e.g. is it ok for it to be 30/70 but not 1/99 ?


Is it possible to disable the Super+ shortcuts that switch to apps in 12.04?

In 12.04 (and prior, I believe), + (like Windows+1) will switch to the first app in the launchbar. Can I disable this somewhere? I like to use Super+Number to switch between workspaces.


After solving the first  issue for adsense (i.e “Unable to review your site” - AdSense),  again i applied to Google ad-sense with live blank ads on page, but In second review they disapproved my website by saying "- Insufficient content"  .   What should do now?


Regex for Email Address along with name format

For email address I am using regex as  var emailRegex = /^([\w-.]+@([\w-]+.)+[\w-]{2,4})?$/  What is regex for   LastName FirstName <lastName.firstName@gmail.com>


I'm trying to validate the local name portion of an email address.   The domain name gets pre-populate so I don't have to worry about that part.   Is there a regex expression that I can use to do this?


How to compare String value to uID Firebase

The problem seems really confusing to me. I try to compare value at 0 index from a String list to uID.toString() and somehow it returns that these String differs from each other. I might not know how it works and actually haven't found a solution yet.   Thats my code: participateButton = findViewById(R.id.button2);     participateButton.setOnClickListener(new View.OnClickListener() {         @Override         public void onClick(View v) {             FirebaseDatabase.getInstance().getReference("Sports").child("Running").child(getIntent().getStringExtra("id")).child("teammateID").addListenerForSingleValueEvent(new ValueEventListener() {                 @Override                 public void onDataChange(@NonNull DataSnapshot snapshot) {                     ArrayList<String> list = (ArrayList<String>)snapshot.getValue();                     Log.d("TAG", list.get(0));                     Log.d("TAG", FirebaseAuth.getInstance().getUid().toString());                     Log.d("TAG", Boolean.toString(list.get(0)!=FirebaseAuth.getInstance().getUid().toString()));                     if(list.get(0) != FirebaseAuth.getInstance().getUid().toString() && list.size() < 2){                         list.add(FirebaseAuth.getInstance().getUid());                         FirebaseDatabase.getInstance().getReference("Sports").child("Running").child(getIntent().getStringExtra("id")).child("teammateID").setValue(list);                     }                     else{                         Toast.makeText(v.getContext(), "You are already signed!", Toast.LENGTH_SHORT).show();                     }                 }                  @Override                 public void onCancelled(@NonNull DatabaseError error) {                  }             });         }     });


Find a closed form for $\sum_{k=0}^{n} k^3$.  I would appreciate ideas for approaching questions like this in general as well.  Thanks.


Passing optional arguments to a function

I would like to pass an undefined number of optional arguments to a function. The optional arguments are stored a priori in a dictionary.  As an example:  def f(a=0, b=0, c=0):     return a  my_args = {'a':5, 'b':3}  print(f(my_args))   The expected output would be 5, however it is {'a':5, 'b':3}


Why are trig-functions standard in radians as opposed to degrees?  I was wondering about this because when differentiating a trig-function in degrees one should apply the chain-rule: $$\frac d{dx}\sin x^\circ=\frac\pi{180}\cos x^\circ$$ Why could the degrees not be the standard?


Proof of a limit for a recursively-defined sequence

I have a sequence defined by $$ a_1=1,\quad a_2=1,\quad a_n=\frac{1}{a_{n-1}}+\frac{1}{a_{n-2}}\text{ for } n\ge2. $$ Now, if $\lim_{n\to \infty}a_n=g$ then $\lim_{n\to \infty}a_n=\lim_{n\to \infty}\Bigl(\frac{1}{a_{n-1}}+\frac{1}{a_{n-2}}\Bigr)=\frac{2}{g}$ so $g=\sqrt{2}$ or $g=-\sqrt{2}$ but $a_n>0$ so $g=\sqrt{2}$.  Now, how do I prove that it has an actual  limit? Also, it can be proven that $1\le a_n\le2$, and it's not monotonic because $a_4 \gt a_5 \lt a_6$. Also, it's not monotonic after some $N\in\mathbb N$


I was given the following as part of a course on Abstract Mathematics that I am currently busy with. It is from a Book "An Introduction to Mathematical Reasoning" by Eccles.  For all integers $n$ such that $n\geq4$, we have the inequality $n^2\leq2^n$ .  Construct a proof. The inductive step of a proof by induction on $n$ reads  $$k^2 \leq2^k \implies (k+1)^2 \leq 2^{k+1}$$ For integers $k\geq 4$.  The book then claims,  "We can achieve the right-hand side of the conclusion inequality by multiplying the hypothesis inequality by $2$, giving:"  $$2k^2 \leq 2^{k+1}$$  I do not understand how $2k^2 \leq 2^{k+1}$ was arrived at.  Could somebody expand the previous line?


Heres how i call the image  Icon logoOne = new ImageIcon("logo.png"); // LOGO JLabel imageLogo = new JLabel(logoOne);  imageLogo.setPreferredSize(new Dimension(200, 50));   Its just added to a panel in a JFrame and works fine when running in eclipse but doesnt show up when exported to JAR.  can anyone help ?


show that:      $$\lim_{n\to\infty}n\left[\left(\dfrac{1}{\pi}\left(\sin{\left(\dfrac{\pi}{\sqrt{n^2+1}}\right)}+ \sin{\left(\dfrac{\pi}{\sqrt{n^2+2}}\right)}+\cdots+\sin{\left(\dfrac{\pi}{\sqrt{n^2+n}}\right)} \right)\right)^n-\dfrac{1}{\sqrt[4]{e}}\right]=-\dfrac{1}{\sqrt[4]{e}}\left(\dfrac{31}{96}+\dfrac{\pi^2}{6}\right)$$   I only solve this :$$\lim_{n\to\infty}\left(\dfrac{1}{\pi}\sum_{i=1}^{n}\sin{\left(\dfrac{\pi}{\sqrt{n^2+i}}\right)}\right)^n=\dfrac{1}{\sqrt[4]{e}}\tag{1}$$ use $$\sin{x}\approx x,\Longrightarrow \dfrac{1}{\pi}\sin{(\dfrac{\pi}{\sqrt{n^2+i}})}=\dfrac{1}{\sqrt{n^2+i}}+o(\dfrac{1}{\sqrt{n^2+i}})\to \dfrac{1}{n}\left(1+\dfrac{i}{n^2}\right)^{-\frac{1}{2}},n\to\infty$$ and note $$(1+x)^{-1/2}=1-\dfrac{1}{2}x+o(x)$$ so $$\lim_{n\to\infty}\left(\dfrac{1}{\pi}\sum_{i=1}^{n}\sin{\left(\dfrac{\pi}{\sqrt{n^2+i}}\right)}\right)^n=\lim_{n\to\infty}\left(\dfrac{1}{n}\sum_{i=1}^{n}\left(1-\dfrac{i}{2n^2}+o(i/n^2)\right)\right)^n=e^{-\frac{1}{4}}$$  But I can't solve my problem,Thank you


Match-3 algorithm to fill empty space left from removing matches

I am currently creating a match 3 game.   I am at the point where I have objects dropping down in the column when only one item is removed. So if an item is removed, the above item moves into its old position etc.  The problem I am having now is that when more than one item is removed from a column, the items in that column only drop down to the first item that was removed. Instead of filling in both items that were removed it just drops down to fill in the first one.   So basically, if two(or more) items are removed from a column the second, third, fourth, etc positions are left blank.  The way I am designing my game is I am using units of 1. So each item takes up 1 unit by x and 1 unit by y. This means that I can position the items like in a grid, at 0x1, 0x2, etc.   What kind of algorithm could I use to move multiple items down to fill the empty space?


Behavior of a pair of integers under simple iterations

The  was deleted by the OP for some unknown reason. I think this was a cute and interesting problem, and I'd really like to know the answer, so I'm just reposting the same question (with a little rewording). Let's consider an initial pair of integers $(a_0,b_0)$ taken in the $\{1,1000\}$ range. Now we iteratively apply one of two simple transformations to such pair, either $$ (a_n,b_n) \to (a_{n+1}=2a_n, b_{n+1}=b_n+1) $$ or $$ (a_n,b_n) \to (a_{n+1}=a_n+1, b_{n+1}=2b_n) $$ Put in simple words, increment one of the elements of the pair, and simultaneously double the other one. Question: does there exist a $(a_0,b_0)$ pair of integers such that there is no path leading to a pair of equal integers?  In a comment of the original question, I expressed the thought that an attack on the problem should probably take the binary representations of the integers into consideration. For instance $$ \array{ 7 \texttt{ 111} \cr 5 \texttt{ 101}  } \to \array{ 14 \texttt{ 1110} \cr 6 \texttt{ 110}  } \to \array{ 28 \texttt{ 11100} \cr 7 \texttt{ 111  }  } \to \array{ 29 \texttt{ 11101} \cr 14 \texttt{ 1110 }  } \to \array{ 58 \texttt{ 111010} \cr 15 \texttt{ 1111 }  } \to \array{ 59 \texttt{ 111011} \cr 30 \texttt{ 11110 }  } \to \array{ 60 \texttt{ 111100} \cr 60 \texttt{ 111100}  } $$ And in another comment, responding to Henry mentioning that he had not yet found a path to equality for $(15,22)$, I responded that there was a path to $123084$, outlining my process to find that path. Essentially, for $$ \begin{array}{rl} 15 &\texttt{1111} \cr 22 &\texttt{10110}  \end{array} $$ to have a chance to reach equality, we have to set to $1$ that second bit of $22$, and we need to do it as soon as possible, which means $8$ additions first to reach $$ \begin{array}{rl} 3840 &\texttt{ 111100000000} \cr 30 &\texttt{ 11110}  \end{array} $$ Now compensating for the length of the binary representation, we get to $$ \begin{array}{rl} 3845 &\texttt{ 111100000101} \cr 960 &\texttt{ 1111000000}  \end{array} $$ and with a final step $$ \begin{array}{rl} 7690 &\texttt{ 1111000001010} \cr 961 &\texttt{ 1111000001}  \end{array} $$ we show that we have transformed the problem from $(15,22)$ to $(10,1)$. And there's a path from $(10,1)$ to $(4,1)$, which resolves as shown above in the $(7,5)$ example (the same sequence of operations that brings $(28,7)$ to equality will work identically on $(4,1)$).


What is the proof of the formula for $\delta(g(x))$?

Consider a function $g(x)$ such that the delta-function is given by $\delta(g(x))$, with $g(x)=0$ at $x_i$. Then we have that $$\sum_i=\frac{\delta(x-x_i)}{|g(x_i)|}.$$  Can someone suggest me a page with a good proof or show me the proof themselves? Thanks.


How can high-activity questions be more wiki-like, driven by the community?

Some old questions on SE have 1M+ views, and many of them have 30+ answers. See  for the ~1000 most viewed questions. From just the first page of results:     35 answers  (in Javascript)  96 answers   50 answers   Correct me if I am wrong, but such questions:   Are likely to be the first answer a new user sees on the SE sites Are viewed a lot by users having beginner level questions Are a pain to read to find the best solution, because each answer/comment might contain an important update to the originally accepted answer have many more answers than actually different solutions   Also SE wants to be more beginner friendly (and that includes a lot of people who are beginners in the topic of an SE site like SO).  I believe these questions are not the most helpful to those users that are most likely to see them. There is a lot of meaningful activity on these questions, but the result is quite messy. How can anyone know whether the most useful answer will be on page 3 of all results?  Now imagine those questions were wikipedia pages on the topic. And all answerers who added one more answer instead cooperated on writing a single article summarizing all answers in the most useful way, uopdating as technology evolved. Would this not be a much more useful way of answering those questions, and a much better impression for first-time visitors to SE?  Of course the authors of these questions and accepted answers could voluntarily turn those into community wikis if they were so inclined, and some such questions are. But it seems to me there is some potential of making such highly visible pages much more useful to those most likely to visit them (the beginners), by being more easily editable by the community without waiting for askers and answerers to switch to community wiki. (Also I believe the reputation gains from such questions are a bad measure of what reputation should be measuring, but that's a different topic).  Now I am wary of suggesting any single change, because most change suggestions get downvoted on meta, so I'll just ask if there is any great idea in meta on making those pages better ambassadors for SE, and wasting less time of the community writing duplicate answers and readers finding information across all answers.  EDIT:    not sure how as a User I am supposed to use those locks on those questions, in any case the question seems from 2013, and not have much effect on the 1M most viewed questions. Locks in general seem to be applied to questions with conflicts like edit wars, or questions that are slightly off-topic, none of which is what I refer to in my question.  seems to be close enough to close this question as duplicate, though I accepted one from meta-SE instead.


I've been following BlenderGuru's tutorials on making a donut and cup.    I've gotten right to the end and now when I click 'Render Image', I don't get the icing:    The particles (sprinkles) are displaying, but not the pink icing.  I cannot figure out why.  The blender file is here:   And a screenshot of Blender:   Can anyone help me figure out why?


Heisenberg's uncertainty principle - Planck's (reduced) constant divided by $2$ or not?

The most common form of  I've seen online is $$ \Delta x \Delta p ~\geq~ \dfrac{\hbar}{2}.$$  However, I also regularly see $$\Delta x \Delta p ~\geq~ \hbar. $$  Sadly, I used the latter one in a project recently and I'm afraid it's incorrect. Obviously the upper one one is true if the latter one is, but why are these two versions used instead of only one of them?


Preventing RDP screen to go black when minimized

I am running some automated scripts on VM nodes and using certain tools to create a video capture of whatever is happening on the screen. One of the limitations of the video capturing software is that the screen on the remote machine must be rendered, meaning that I must have an active RDP session to the VM as long as I want the screen to be captured. That all works fine when I create an RDP session (mstsc) to that VM and leave it on my screen. However, when I minimize the RDP session, it seems like the remote screen becomes black and as a result prevents video capture.   I wonder where there is a way I can force the RDP session to render the screen as usual, even when the window is minimized?


Edit:  Ok, user  made comment that truly helps narrow the focus of my question. Basically, I'm asking for a self-study course of Mathematical Methods.  Thanks to his recommendation I identified a book that is very close to the answer:  Mathematical Methods in the Physical Sciences by Mary L. Boas  Supposedly, the book covers most of the Math a person needs to learn in order to understand the simulations I presented.  Does this book suit my needs?    Hello,  I have always been interested on the idea to study Math at an Undergraduate level to be able to implement simulations like the followings:  Finite Difference Simulation of the Wave Equation    Heat Equation in Two Dimensions    Besides my precollege experience in Math, I have only been able to do very simple simulations due to my lack of knowledge of Advanced Math. Every time I ask about the inner workings of the simulations I get redirected to papers that look like foreign language to me and, unfortunately, I depend on easy-to-read tutorials to understand them, and while I have found   I'm more interested in reaching the solution myself.  I checked some of the questions related to book recommendations for self-study and while they are very helpful I'm interested in learning by example (There is a book called: "Accelerated C++ Practical Programming by Example" that fits very well my study habits)  Thanks in advance.


Research reference or source for study before selecting thesis topic

I would like to do my master thesis on image processing. What will be best approach for study and selecting topic on this field?


I am starting up a brand and I gave my artist a few statue of liberty images from Pinterest for inspiration. The first image is the one he used for inspiration the most and the second image is the logo he came up with. Are they too similar? Inspiration -  Our Logo -


Attempt to invoke virtual method 'android.view.View android.view.View.findViewById(int)'

It is showing error -> at com.thoughtworks.mythoughtworks.MainActivity.onCreateOptionsMenu(MainActivity.java:66)  .It is showing null pointer exception  when I load notification badge in onCreateOptionMenu...  Please help     MainActivity.java   public class MainActivity extends AppCompatActivity {   ProgressDialog progress; ListView ls; int count = 0; SearchView searchView; NotificationBadge badge;  @Override protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.activity_main);     ls = (ListView)findViewById(R.id.listView);     progress = new ProgressDialog(this);     BackgroundTask process = new BackgroundTask();     process.execute(); }  @Override public boolean onCreateOptionsMenu(Menu menu) {     getMenuInflater().inflate(R.menu.menu_main,menu);     View mview = menu.findItem(R.id.cart).getActionView();     badge = (NotificationBadge) mview.findViewById(R.id.badge);     //updateCartCount();     return true; } private void updateCartCount(){     if(badge == null) return;     runOnUiThread(new Runnable() {         @Override         public void run() {             badge.setVisibility(View.VISIBLE);             badge.setText("2");         }     }); } @Override public boolean onOptionsItemSelected(MenuItem item){     switch(item.getItemId()){         case R.id.cart:             Toast.makeText(this, "cart", Toast.LENGTH_SHORT).show();             break;


Possible Duplicate:          I have tried changing my proxy settings in a terminal as:  export HTTP_PROXY=http://10.1.3.1:8080   and  export http_proxy=http://10.1.3.1:8080   but when I try to install a new package or update apt-get, apt-get starts displaying messages from which it seems it is trying to connect to a previously set proxy:  sudo apt-get update   0% [Connecting to 10.1.2.2 (10.1.2.2)] [Connecting to 10.1.2.2 (10.1.2.2)   I have tried setting the proxy via bashrc file but that din work either. As far as I remember 10.1.2.2 was set using GNOME GUI but I don't have access to the GUI right now so I am trying to set it from terminal.


Im trying to dinamically insert names into the value of an input element. I try to pass players[i] as an argument for the function addPlayer but it says undefined. When I click on each name it should be passing it to the input field. Where am I failing?  var players = ["john","doe"];  function addPlayer(str) {     console.log(str);     document.getElementsByClassName("answerInput")[0].value += str; }   for (var i = 0; i < players.length; i++) {     var node = document.createElement("div");     var textnode = document.createTextNode(players[i]);     node.appendChild(textnode);     node.classList.add("newPlayers");     document.getElementById("pushPlayer").appendChild(node);     node.addEventListener('click', function () {            addPlayer(players[i]);         }, false); };


I visited the site  to do some study and found that this site uses mini-profiler. I believe devs generally use it when the app is in test/development mode. So was wondering if the mini-profiler was left like that on purpose or it was not taken care of while deploying to prod?


At first glance it seems like "Did they stole the bike?" doesn't sound right.  I was going to correct that user and tell him it's steal.  However, when I look up the word stole, it's labeled as .  It sounds funny to say "Did they stole the bike?", but what really is the difference between steal and stole?   Because when saying "Did they", that's inferring the past, right? So would stole actually work as it's past tense, but just sound funny?


Customise counters, cross references to environments

I would like to make cross references to own defined counter on environments. So far I have tried the following,   \documentclass{book} \newcounter{entryc}[subsection] \newcommand{\thetheorem}{\thesubsection.\arabic{entryc}} \newenvironment{qd}[1]{\refstepcounter{entryc}\noindent\textbf{Quasi Definition \thetheorem.}\begin{itshape}} {\end{itshape}} % \begin{document}  \chapter{First chapter} This is the first chapter.  \section{First section} This is the first section.  \subsection{First subsection} This is the first subsection.  \begin{qd}{}\label{qd:emp} This is my environment. \end{qd}  \noindent In quasi definition \ref{qd:emp} it \dots  \end{document}   What happens is that     But I would prefer "...In quasi definition 1.1.1.1". Do anyone have some suggestions of how solve this? and How to avoid the          \noindent  thing before the continuation of the text?   Additional information: if possible I would try to not use ntheorem.


Is there any information out there on how to start creating scripts using Python and QGIS 2.10? I only have a little coding experience and an very unsure of how to start.  My first script would probably be something like a process for creating a buffer from a point, setting the properties of the buffer too if possible (e.g. orange, 0.8 line). I do simple tasks in QGIS often and I think scripts would help me a lot.


Can a quantum computer simulate a normal computer?

Similar to the question : given a 'classical' algorithm, is it always possible to formulate an equivalent algorithm which can be performed on a quantum computer? If yes, is there some kind of procedure we can follow for this? The resulting algorithm will probably not take full advantage of the possibilities of quantum computing, it's more of a theoretical question.


Caption package messing with Endnotes package

I'm facing a weird problem with caption and endnotes packages. I have some figures and their caption contains endnotes. However, at each call of \endnote, the endnote counter is incremented by 2 instead of 1. It should be 1, 2, 3... but I'm getting 2, 4, 6...  The problem is related to the caption package. If I remove it, problem solved! However, I would like to find a way to solve this issue without removing any package. Can you help?  MWE with the problem:  \documentclass{book}  \usepackage{endnotes}  \usepackage{caption}  \begin{document}  \begin{figure}[h]   \caption[caption for toc]{figure caption\endnote{endnote A}} \end{figure}  \begin{figure}[h]   \caption[caption for toc]{figure caption\endnote{endnote B}} \end{figure}  \theendnotes  \end{document}


Auto-suggestions with HTML on stack overflow causes rendering issues

I was entering an issue on Stack Overflow and one of the auto-suggestions had HTML in the title, and it seemed to break the rendering in my browser.  I'm using the latest stable FireFox for Windows 8.1.  Title of question to reproduce the issue:  Showing m.bing.com in the WebBrowser control   See screenshot:


Prove that, $\binom{3n}{r}=\binom{3n-1}{r} + \binom{3n-1}{r-1}$

Reading through my textbook I came across the following problem and I am looking for some help solving it.  Prove that,  $$\binom{3n}{r}=\binom{3n-1}{r} + \binom{3n-1}{r-1}$$  In a previous problem I solved the following but I wasn't sure how to use it to prove the question above. Prove,  $$\binom{n}{r}=\binom{n}{n-r}$$  Solution:  left Side,  $$\binom{n}{r}=\frac{n!}{(n-r)!r!}$$  right side,  $$\binom{n}{n-r}=\frac{n!}{(n-(n-r))!(n-r)!} = \frac{n!}{(n-r)!r!}$$  Therefore completing the proof,  but how do I solve my first question? thanks!


What is a catchy word that means (non-)self-descriptive

I'm having fun with paradoxes, and I'm trying to come up with a catchy word for non-self-descriptive.  Maybe "autosemantic" fits the bill for self-descriptive (definitely open to other suggestions!), but I'm having a hard time negating it in a natural way.  For an example of the sentence I'm trying to construct:     Is "inautosemantic" inautosemantic?   It just isn't flowing.


How can I use the same material at another slot and change it independently?

I modelled something and want to select some specific faces for this object to give it another material. Works with applying. But now I have an existing material and don't know how to change it (e.g. make it darker) without changing it for all the other faces too.  When I click on the second material slot and want to change it and apply, the first slot changes too. How do I avoid that?


How to draw software architecture in Latex?

I want to generate something like this in Latex    I've already checked  but wasn't able to generate something visually appealing.   I just need a general idea on how to do it on my own, you don't need to post the whole picture (also no problem if you want to :) )


JScript tag on SO becomes JavaScript tag

First to clear any confusion, JScript is NOT JavaScript.  In  no matter how hard I try, it's not possible to change the  into the more proper  tag - the jscript tag is recognized, I can select it, I can save the edit and..... the javascript tag appears instead.  I guess it's "global" problem with the jscript tag but don't want to litter SO with test questions.  Edit: looks like it's not relevant anymore:


Is my CPU core/CPU proximity too high in temperature?

As mentioned by the title 'is my CPU core/CPU proximity to high in temperature?'. The underneath of my macbook gets seriously hot. Not only this but if an application is being 'verified' when opened or when I open a browser such as google chrome, the fans get extremely noisy. I've had a look online but there seems to be difference of opinion. Can anyone tell me what they think with the stats below? It averages around 70s/80s.


When estimating variance, why do unbiased estimators divide by n-1 yet maximum likelihood estimates divide by n?

I am totally confused: On the one hand you can read all kinds of explanations why you have to divide by n-1 to get an unbiased estimator for the (unknown) population variance (degrees of freedom, not defined for sample size 1 etc.) - see e.g.  or .  On the other hand when it comes to variance estimation of a supposed normal distribution all of this doesn't seem to be true anymore. There it is said that the maximum likelihood estimator for variance includes only a division by n - see e.g. .  Now, can anyone please enlighten me why it is true here but not there? I mean normality is what most models boil down to (not least due to the ). So is the choice "division by n" yet the best choice for finding the best estimation for the true population variance after all?!?


How to safely encode cidr notation in url?

I'm working on an application that does some basic network management. Due to constraints outside of the scope of this application, there's a need to encode a cidr block (eg 127.0.0.1/32) into the url. For instance, an endpoint route might look something like this post "/home/network/:user/:cidr". In most cases, one could easily send the cidr as a string in the payload but that is not an option here.  I know that . is a valid url character and that / can be encoded with %2F. Naively combining these and attempting to post against that endpoint like so: /home/network/janedoe/127.0.0.1%2F32 404ed which makes me think Sinatra isn't able to properly parse that url parameter. I've also tried using the URI module to encode the cidr string with no luck so far.  Perhaps there's an easier way to think about encoding the cidr block into the url that makes for easy extraction in the endpoint.


At the end of Star Wars: The Force Awakens we see two related events:      Rey defeats Kylo Ren in combat, but there is no clear indication that he died. His wounds appear to be to extremities or other non-vital areas such as his shoulder. This leads me to believe he is still alive, and primed to turn mechanical like his grandfather did four movies prior after being defeated in a lightsaber fight with Obi-Wan. This is speculation, as the movie is not specific here.   Also:      Snoke tells General Hux to grab Kylo Ren and flee the planet so Kylo Ren can complete his training.   However, there is no visual indication about what happens to Kylo Ren after the final events on the planet. We see the Millennium Falcon leaving, but no other ships.  Did Kylo Ren leave the planet with General Hux at the end of the film? Is there any canon answer in the novelization or other sources?


java.lang.RuntimeException: Android Runtime error

I am new to development of android and i don't have a fair idea how to read logcat. I am trying to develop android webview application but ran into these errors.  E/AndroidRuntime:  FATAL EXCEPTION: main E/AndroidRuntime:  Process: com.tech.neucial, PID: 25698 E/AndroidRuntime:  java.lang.RuntimeException: Unable to start activity ComponentInfo{com.tech.neucial/com.tech.neucial.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.app.ActionBar.setHomeButtonEnabled(boolean)' on a null object reference E/AndroidRuntime:   at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2329) E/AndroidRuntime:   at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2391) E/AndroidRuntime:   at android.app.ActivityThread.access$900(ActivityThread.java:147) E/AndroidRuntime:   at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1296) E/AndroidRuntime:   at android.os.Handler.dispatchMessage(Handler.java:102) E/AndroidRuntime:   at android.os.Looper.loop(Looper.java:135) E/AndroidRuntime:   at android.app.ActivityThread.main(ActivityThread.java:5256) E/AndroidRuntime:   at java.lang.reflect.Method.invoke(Native Method) E/AndroidRuntime:   at java.lang.reflect.Method.invoke(Method.java:372) E/AndroidRuntime:   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:898) E/AndroidRuntime:   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:693) E/AndroidRuntime:  Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.app.ActionBar.setHomeButtonEnabled(boolean)' on a null object reference E/AndroidRuntime:   at com.tech.neucial.MainActivity.onCreate(MainActivity.java:39) E/AndroidRuntime:   at android.app.Activity.performCreate(Activity.java:5933) E/AndroidRuntime:   at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105) E/AndroidRuntime:   at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2282) E/AndroidRuntime:   ... 10 more   I have tried every possible way to understand but no resolve. Here is the source code.   PS: i am uploading whole source because i don't know which file has cause the issue and there have been 5 or 6 files which i can't paste here.  Thanks.


Sci-Fi Drama TV Series about telepathy between an alien and a boy

I'm trying to remember this show, 80's or early 90's, about a boy who receives telepathic messages from an alien, and his family thinks he's going crazy. All very serious and dark. The only thing I remember are the credits and cuts to commercials: they show the protagonist's head over an eerie landscape, spinning very slowly and fading into an alien's egg or something.   The name of the show was the name of the boy, very simple, one word... Ben, or Max, or anything like that.


I used to work with two displays. As usual I make full screen on the second monitor for watching web video while continuing to work on the laptop monitor.  In Ubuntu it's always opening in full screen mode on the laptop monitor.  Is it possible to open full screen on the second monitor if so,how can I do this?


¿What is the difference between scores and Principal Components in PCA?

OK, this question may already be answered but I do not quite understand all of it. So I have understood that scores loadings and principal components are different concepts: Scores: Are the new coordinates of the observations in the new space defined by PC. (There is no such thing as first principal component score) Loadings: They are the coefficients of the linear combination of the original variables in orher to form the principal components. Then in a   they mention that a principal component is a linear combination of what ? Is a linear combination of loadings and the original observed variables ? Then, a score is what ? the component of the PC vector ?


I have a query that uses a couple joins to get a name from another table.  It works okay except that I would like to combine "Examiners Name" instead of having multiple duplicates:  ID    |  Name       | Examiners Name 1290  | Jun         | Aron 1290  | Jun         | Mark 1292  | Takahiro    | Didier 1292  | Takahiro    | Eiro 1292  | Takahiro    | Kurt    What I am looking for:  ID    |  Name       | Examiners Name 1290  | Jun         | Aron, Mark 1292  | Takahiro    | Didier, Eiro, Kurt   Here is my query:  SELECT DISTINCT usr.CandidateID, usr.FirstName, Examiner.FirstName AS [Examiners Name] FROM dbo.tbl_User AS usr LEFT JOIN dbo.Tbl_ExaminerCandidates AS ExamCa ON usr.UserID = ExamCa.CandidateID LEFT JOIN dbo.tbl_User AS Examiner ON ExamCa.ExaminerID = Examiner.UserID WHERE usr.CandidateID IS NOT NULL AND usr.IsActive = 1 AND usr.UserStatus = 1   I have been looking around but I cannot find a way to do this. I am using SQL Server 2008.


Do votes down on an answer canceled for deleting it?

I mistakenly answered a question and got voted down. Now, I've learned the lesson, can I delete the answer to cancel the votes (after all, the voting mechanism purpose is to give feedback to the writer, and help the readers to get the right answers)?


My personalized link for Careers 2.0 profile does not work

When I click on the customized link on my Careers 2.0 profile page or copy/paste it into a browser I'm getting Page Not Found page. It used to work.  Is something broken?


What are the guidelines for flagging posts for migration to another site?

I see a post on site A that I want to migrate to site B (where site B is not on the list of eligible sites for migration when closing a question as off topic, or I don't have enough reputation to vote-to-close yet).    What are guidelines should I follow before flagging that post for migration?


Better HTTPS support for Stack Exchange sites

So it looks like Stack Exchange now supports HTTPS (to some extent). Which is awesome! But there are a few problems, the main one being that some content is delivered over the CDN, which is plain HTTP. This causes browsers to complain about "unsecured content":


Winning strategy in game of cutting rectangle

There is a bar of chocolate of size $N$ x $M$. Little square $(x, y)$ is poisoned. There are 2 players taking turns. In each move they can cut the bar along any of the horizontal or vertical lines, then the part which does not contain $(x, y)$ is being eaten. The player who is left only with square $(x, y)$ loses (beacause it is poisoned). Which player has the winning strategy? I guess that this game is equivalent to game of Nim due to Sprauge-Grundy theorem, but I don't know how.


NullPointerException happens for some list items

I have a custom listview in my app which fills by JSON and I'm using bitmap to fill images in listView and I want to get a TextView value inside the list item that has been clicked  lView.setOnItemClickListener(new AdapterView.OnItemClickListener() {   @Override   public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {     try {           hotel_id = (int) adapterView.getItemIdAtPosition(i);           TextView id= (TextView) lView.getChildAt(i).findViewById(R.id.aNametxt);           type_id_post = deleteIcon.getText().toString();            backgroundTask = new BackgroundTask(textView);           backgroundTask.execute();            Intent intent = new Intent(RoomList.this, RoomPopUp.class);           startActivity(intent);          }     catch (RuntimeException e){           e.printStackTrace();     }   } });   and it works for the first two items of the list but for another item app will stop on hotel_id definition line and this is logcat when I click an item except for the first two items :  08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: java.lang.NullPointerException 08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: at com.test.RoomList$1.onItemClick(RoomList.java:126) 08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: at android.widget.AdapterView.performItemClick(AdapterView.java:299) 08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: at android.widget.AbsListView.performItemClick(AbsListView.java:1158) 08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: at android.widget.AbsListView$PerformClick.run(AbsListView.java:2957) 08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: at android.widget.AbsListView$3.run(AbsListView.java:3849) 08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: at android.os.Handler.handleCallback(Handler.java:733) 08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: at android.os.Handler.dispatchMessage(Handler.java:95) 08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: at android.os.Looper.loop(Looper.java:136) 08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: at android.app.ActivityThread.main(ActivityThread.java:5105) 08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: at java.lang.reflect.Method.invokeNative(Native Method) 08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: at java.lang.reflect.Method.invoke(Method.java:515) 08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:792) 08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:608) 08-07 11:43:36.026 14747-14747/com.moalem.khane.khanemoalem W/System.err: at dalvik.system.NativeStart.main(Native Method)   the point is all item's id TextView of the list are casting to one id but it for "SOME" items that id is null is there anyone who knows what is the problem of this?


How to create Shortcut to a Web Page in Linux?

I am new to Linux and am not a supergeek.  You cannot drag things on to the desktop with Ubuntu 16.04.1 like you can in Windows 7.  I would like to create a shortcut to .  How can I do that?


Community FAQ For sites in the Stack Exchange 2.0 network To see a list of commonly used words and phrases, see the . For official guidance from Stack Exchange, visit the . Asking questions                            Answering questions                 Accepting answers        Working with posts  What does it mean when a question or answer is...  ?  ?  ?  ?                                       Comments             Etiquette                         Promotion         Editing and Formatting                                    Tagging                      Reputation, badges, and voting                                         Moderation                                                 Searching and RSS feeds        Accounts, registration and logging in                                     Other                                 ()                                 Site-specific entries Stack Overflow             Meta Stack Exchange       Other     External links           Is your question not part of the FAQ? First look at questions tagged  to see if there is a question not in this index that might have the answer you seek. If you still can't find an answer, then see the following instructions for proposing an FAQ question. How can a question be added to this FAQ?  Ask only the question, stated plainly and simply, in the question body. The answer goes in an answer.  Link back to this index. Paste this at the end of the question:  [Return to FAQ index](/q/7931)   Tag as  and .  When a post seems to have hit a mature state, it will have  added by a moderator.  Flag for a moderator to mark community wiki.  Any FAQ post not yet community wiki should be made into a community wiki.  After the post has the  tag added to it, add a link in the above .


How do I make vim the default graphical text editor?

While trying to make vim default instead of gedit, I found this could be done two ways:  Use defaults.list and make text/plain (and others) point to vim.desktop (what is the format for creating .desktop files?)  Use update-alternatives and change gnome-text-editor (right now it has only one alternative, so I guess I have to install one more. How to do that?)  and which is the better way to do it?


How should I restrain myself when both playing a character and DMing?

I'm currently playing an IRL game with two of my friends. As you might imagine, I was worried that they weren't powerful enough to take on the higher level encounters so I made a character to help them out. They were both new to D&D so I didn't want to overload them with a gestalt character. However, now I'm worried that I might use my DM powers to make my character more powerful than the other two.  I just want to know something to help prevent myself from using my magic DM powers for evil.  Right now, we have a sorcerer and monk so I was considering making a tank-ish cleric.


Say I do the following:  cd /some/path ln -s /target/path symbolic_name   If then do:  cd /some/path cd symbolic_name pwd   I get:  /some/path/symblic_name   and not:  /target/path   Is there a way to have the shell "fully resolve" a symbolic link (i.e. updating CWD, etc.), as if I had directly done:  cd /target/path   ?  I need to run some programs that seem to be "aware" or "sensitive" about how I get to my target path, and I would like them to think that I arrived to the target path as if had done cd /target/path directly.


iPod iOS 5.1.1 safe mode without any touchscreen controls

I have a safe mode issue with my iPod touch fourth gen. IOS: 5.1.1. It was working just fine for about a year and then the other day I installed a tweak that allowed for vertical scrolling of the home screen from HYI repo (I tried to install the same tweak a few months ago along with another tweak and I got booted into safe mode but everything worked fine in safe mode, so I went into Cydia and uninstalled the two tweaks thinking that they were conflicting with each other. After that I re-sprang it and it worked like normal.) and I got booted like normal but this time it froze on lock screen and then booted into safe mode. (o_O) THIS time my touch screen wouldn't work. So I forced re-booted it by holding the home and lock button until the screen flashed white and then showed the apple boot logo. After that I uninstalled the tweak and it worked fine. Today I just installed two add ons and upgraded HTML Widgets related to SB Settings. The other two add ons were iOS 7 ringtones and notification alert sounds. Yet again I was greeted by my usual lock screen pic and then the safe mode black picture lock screen, again, my touch screen wouldn't work but the buttons would. So I just re-booted it by holding the buttons thinking it would solve the problems, but of course, it did nothing to solve it... Now this time I am actually stuck in safe mode and do not want to restore my jailbreak because I have a bunch of tweaks and settings I worked really hard on.  PLEASE could SOMEONE fix this problem with the safe mode and SB Settings tweaks?! I am clueless with what to do.  Thanks!


MTG: Can I use the ability of my Five-Alarm Fire before it getting destroyed? How does priority works here?

Say for instance my opponent uses  against my  ... can I use the counters on it to deal damage before it getting destroyed? Also can I use those counters to deal damage at anytime in any players turn?


[Beginning calculus question.] I saw in a calculus lecture  that for a position vector $\boldsymbol{r}$  $$\left|\frac{d\boldsymbol r}{dt}\right| \neq  \frac{d\left| \boldsymbol r \right|}{dt}$$  but I don't understand exactly how to parse this.   It's my understanding that:    $\frac{d\boldsymbol r}{dt}$ refers to the rate of change in the position over time (speed?) $|\boldsymbol r|$ refers to the magnitude of the position, i.e. the distance (from what to what?) $\frac{d\left| \boldsymbol r \right|}{dt}$ refers to the rate of change in distance traveled over time, (a different kind of speed?)   Is there a good way to understand what both of these expressions mean?


Is the Blood Fury Tattoo's damage doubled on a critical hit?

The question is as the title says, is the 4d6 necrotic damage doubled if you critted the attack that you then use the item's ability on. The item text in question is below.  When you hit a creature with a weapon attack, you can expend a charge to deal an extra 4d6 necrotic damage to the target, and you regain a number of hit points equal to the necrotic damage dealt.


Light was known to be a wave but had to be considered as made up of lumps not waves to explain ultraviolet catastrophe. Why?

Refer the title. Why was this required? How is this related to ultraviolet catastrophe?


How do I randomly pick n items from an array with a seed that can let the randomization fixed when giving a fixed seed in JavaScript?

Say I have an array var arr = [1,2,3,4,5,6,7,8,9]. It's not hard to have a function for me to pick n items from it randomly like this: function pick_n_from_array(n, array) {   return array.slice(0, n).map(function() {     return this.splice(Math.floor(Math.random() * this.length), 1)[0];   }, array.slice()); } pick_n_from_array(3, arr); // [3,5,8]; pick_n_from_array(2, arr); // [2,8]; pick_n_from_array(3, arr); // [5,7,9];  However, I'm thinking about picking it with a seed, that once you give the same seed, you get the same pick: pick_n_from_array_by_seed(3, arr, 1); // [3,5,8]; pick_n_from_array_by_seed(3, arr, 1); // [3,5,8]; pick_n_from_array_by_seed(3, arr, 2); // [5,7,9];  I have found some related questions (for ) but not in JavaScript.


Visualization of relation between integration and derivative operations

If I have a function $f(x)$ and I find the derivative I will get $f'(x)$. Furthermore, if I do the integration of the derivative $f'(x)$, as a result I will get again my original function $f(x)$.  What I do not understand is a relation between integration and derivative operations. For me, the derivative is an operation where we calculate the slope of a function, and integration is an area under a curve.  But, if we take an example where $f(x) = x^3$. The derivative is $f'(x) = 3x^2$. If we do the integration of the $3x^2$ we will get our $x^3$ back again. But, $3x^2$ is some function, and if we do the integration on it, we should get its area under the $3x^2$. Is it possible to visualize that relation between derivative and integral operation, because I do not see it from the graph below?


I am programming a simulated online banking client in java. I need the ability (or an alternative) to be able to continue from a label. This is a snippet from my code so far.      Main:     {     for ( ; ;) {     System.out.println("Welcome to Tamarin© online banking!");     System.out.println("Select register or login:");      choice = scan.nextLine();      if (choice.equalsIgnoreCase("register")) {         register:         {         System.out.println("Welcome to register! Please type your username:");         userreg = scan.nextLine();          if (accounts.contains(userreg)) {             System.out.println("Username taken! Try again.");             continue register;   Java is giving me a "continue cannot be used outside of loop" error. Any ideas as to (if the registration fails) I could bring the user back to the last step ('registration' label)? And if not, how could I get this code to work?  (I obviously have closing braces down at the end).


Using Thunderbird to automatically backup my email account

I use Thunderbird to backup my web-based email account: I open Thunderbird and copy the mail messages from the Inbox to a local folder.   Is there a way to do this automatically every day, so that I don't have to open Thunderbird all the time?  EDIT:  is very useful for GMail accounts. For non-GMail account, the getmail method should probably be used.


In the parchment the Goblet of Fire spit out, why wasn't the school name there?

In the Goblet of Fire, students were supposed to put their name and the name of their school in the Parchment they put inside the Goblet.  It is clearly stated that Fred wrote "Fred Weasly, Hogwarts", in his.  But when the parchments come out, the school's name isn't there. It simply says 'Harry Potter'. Why?  Since no one was surprised at the absence of school name, I don't think this was the result of Moody's Confundus charm.


I'm thinking of upgrading from a 9 speed (11-34T cassette) to 10 speed.  Scoped out a few components and  1) Shimano Deore XT CS-M771 10-Speed Cassette 11-36T 10-speed HG cassette 2) Shimano Dyna-Sys, super-narrow 10-speed HG chains (hg95) 3) Shimano Ultegra 6700 Shifter (for 10 speed)  I have an existing Deore XT rear long cage derailleur used to support 9 spped 11-34T cassette.  Two part question:    A) can existing rear derailleur support HyperGlide chain and cassette? B) any other comments on compatibility of proposed new components or suggestions?


Does anyone have IETE journal of Research latex template. I didnt find any latex template. How do i use latex template to follow their guidelines.  Please help.


Restore a database by pointing to one or more directories containing backup files and specifying a STOPAT time

I'm working on prepping/testing migration of our ERP and other auxiliary systems to a new database server. This will involve restoring database backups from the old server onto the new one.  For the sake of convenience, I'd like to be able to use a script/stored procedure to restore a database by simply pointing to one or more directories containing the backup files (combination of full, differential, and log), and optionally specifying a STOPAT time, or omitting it and restoring to the most recent possible time given the backups present. I would also need to be able to specify new file locations (the MOVE option), either explicitly, or more generally "put all the data files here, and all the log files here". The tool should look at all the files in the provided directories, and determine which ones need to be restored to reach the target time.  The GUI restore tool in Management Studio can do all of this, but that obviously can't be included in a script. I'd like to be able to write a general migration script that would be conceptually similar to this:  EXEC master..RestoreDB     @database='ERPSysDB',     @source='\\oldserver\Backup\oldserver\ERPSysDB\FULL,\\oldserver\Backup\oldserver\ERPSysDB\DIFF,\\oldserver\Backup\oldserver\ERPSysDB\LOG',     @datadir='D:\SQLServer\DATA',     @logdir='L:\SQLServer\DATA';  --Do various cleanup/post processing steps in ERPSysDB here  EXEC master..RestoreDB     @database='ERPCompanyDB',     @source='\\oldserver\Backup\oldserver\ERPCompanyDB\FULL,\\oldserver\Backup\oldserver\ERPCompanyDB\DIFF,\\oldserver\Backup\oldserver\ERPCompanyDB\LOG',     @datadir='D:\SQLServer\DATA',     @logdir='L:\SQLServer\DATA';  --More post-processing in ERPCompanyDB here  --Now restore a test copy of the database that we don't back up directly on the production server, --using production database backups instead: EXEC master..RestoreDB     @database='ERPCompanyDB',     @restoreas='ERPCompanyTestDB',     @source='\\oldserver\Backup\oldserver\ERPCompanyDB\FULL,\\oldserver\Backup\oldserver\ERPCompanyDB\DIFF,\\oldserver\Backup\oldserver\ERPCompanyDB\LOG',     @stopat='2018-11-01T08:00:00'     @with='MOVE ''ERPDataFile'' TO ''D:\SQLServer\DATA\ERPCompanyTestDB.mdf'', MOVE ''ERPLogFile'' TO ''L:\SQLServer\DATA\ERPCompanyTestDB.ldf''';  --Additional post-processing, database restores, etc...   Are there any existing tools that provide this functionality? I'm prepared to write my own, but it would be a fairly intricate chunk of code (particularly error/exception handling), so I don't want to reinvent the wheel. I'd prefer this to be usable within T-SQL, i.e. not PowerShell cmdlets, but CLR stored procedures would be fine (and quite possibly the easier/better way to implement this).


I tried to get special characters with the package autonum to work and installed the new version according to .  I downloaded and copied the files with admin rights to the my MiKTeX 2.9 folder (running on Win 7) but it is still not working.   Any idea on how to fix it?  The used minimal example is this one and it doesn't reference correctly  \documentclass{article} \usepackage{amsmath} \usepackage{hyperref} \usepackage{cleveref} \usepackage{autonum} \begin{document}  \begin{equation} a = b \label{eq:a} \end{equation}  \begin{equation} c = d \label{eq:b} \end{equation}  \begin{equation} e = f \label{eq:c} \end{equation}  See \cref{eq:b}. \end{document}    Best regards


how create big vinyl banner 18" wide by 360" high

Help me please I need to create banner 18" wide by 360" high. Illustartor can create max 227,54 in. Its my firs so big banner. Help me please.  Here GUIDELINES: 18" wide by 360" high. Keep artwork text at least 1" away from the left and right edges, and 10" away from the top and the bottom.


I'm new to Blender and last night I was working on a simple animation of cubes falling onto a plane. I saved the blender file and today when I opened it up and tried to render it, it refused to work. If I start a new project and render it, it works fine.  I've made sure that I have lighting, and I've messed with the output settings, but I can't get it to render. I was able to render the entire animation earlier today, but I closed out of Blender and when I reopened it, it renders blank.  This is how it looks when I change to render view in the viewport.   Then this is what the final rendering looks like.    Here's the


Dying person is the last in his race of warriors, trying to find the people who killed his race

All I remember is a guy who is dying from some kind of radiation, and is trying to find and punish the murderer of his race. He is the last of his kind, and has extreme fighting training, and is one of the best from his race. His race was made up of warriors, and could fight and beat nearly any foe. I think the protagonist was called Keith, or Kyle. He has a ship, and some battle equipment, and, if I remember correctly, a pet of some sort. The enemy was an organization called Darkwing or something similar. I can't remember much more, but I liked the books (it was a series) and really want to find it again!


Is it possible to copy an object in Illustrator so that if you make a change in any of them the changes will apply in both? Actually I have this situation where I have a lot of instances of the same object and I need to be faster on changes and copy-ing again and again is not a proper solution, but consumes a lot fo time.  Thank you for your time!


We've seen several examples of their Queen and she always appears to be of the same species. What species is that?


The following error occurred while opening software updater/Ubuntu software center/sypnatic package manager/software sources.  E:Encountered a section with no Package: header,  E:Problem with MergeList /var/lib/apt/lists /ppa.launchpad.net_atareao_atareao_ubuntu_dists_quantal_main_i18n_Translation-en,  E:The package lists or status file could not be parsed or opened.   How to solve this problem?. Any help please.


Why does "ipconfig"not work in my windows 8 elevated command prompt?

Im needing to find my ipv4 address to make a server because my old one was on windows 7 then i upgraded to windows 8, which i now regret because i cant find my computers ipv4 address when i type ipconfig in my elevated (Run as administrator) command prompt. it comes up with the usual error when it does not understand a command  ipconfig is not recognized as an internal or external command, operable program or batch file.  Does anyone know why this is happening or is it just not available on windows 8? i'v seen people do it but that might just be them using a windows 8 skin.  Picture:


Using separation of variables to solve the wave equation

I'm trying to teach myself separation of variables and have been following some notes for the wave equation, but there's one part which really confuses me and I'm not exactly sure how it makes the step.  For the wave equation   $$u_{tt} - c^2 u_{xx} = 0$$   with length $l$ and fixed ends, $u(0,t)=u(l,t)=0$ we seek a solution in the form $$u(x,t)=v(x)q(t)$$  and substituting this into the equation gives $$\frac{1}{q(t)}\frac{d^2 q}{dt^2}=c^2 \frac{1}{v(x)}\frac{d^2 v}{dx^2}=-\omega ^2$$   and I understand all of this so far. But when solving the equation  $$q''+\omega ^2 q = 0$$ the general solution is $$q(t)=A \cos(\omega t +\alpha)$$ where $A$ and $\alpha$ are constants - which is the part which I'm not exactly sure on how it gets to.   Could someone explain this step to me? Thanks!


So I got a new hard drive. First, I downloaded Ubuntu on to it, because I didn't have windows 7 yet. So a few days later I bought windows 7, and partitioned it on to the hard drive.  Now, when I start the computer, it goes straight to windows 7. That's fine and all, but how do I get to the Ubuntu partition that's somewhere on the hard drive still? I believe it is an extended partition, not a primary.


Prove that the real root of $x^3 + x + 1$ is irrational

Using wolframalpha.com we get that the real root of this polynomial is $-0.68233$  The only way that I have found how to prove it is using the Rational Root theorem.  Using that theorem the possible rationals roots are 1 and -1, but none of them work.  Then the real root has to be irrational.   My questions are:   Is there other way to prove it without using the Rational Root Theorem? Is my proof written well?


Where would I ask a question pertaining to an ordinary phone? Or just cell phones in general? I saw Windows Phone while browsing the SE database, nothing else really popped out at me. Google didn't bring up anything either. Is that just too small a community to cover with SE?


Why use "inner Class" instead of using "new" directly?

When I learn guava,I found some code like this in com.google.common.hash.Hashing class:  public static HashFunction crc32c() {     return Crc32cHolder.CRC_32_C; }  private static final class Crc32cHolder {     static final HashFunction CRC_32_C = new Crc32cHashFunction(); }   I want to know, why do not write like below, Is this merely the author's habit? or for other purpose?  public static HashFunction crc32c() {     return new Crc32cHashFunction() }


Get my IP address without 'ifconfig' or 'ip addr'?

I've got a stripped-down Linux container. I want to find out its IP address. I don't have ifconfig or ip installed (and I don't want to install them, since they'd just get deleted when I next rebuild the container).  Can I get the IP address from somewhere in /proc?


Is there an Intelligent Personal Assistant available in Ubuntu?

I am new to Ubuntu and I was wondering if there was an  like Cortana or Siri in the software center.


I've written a package that introduces a new environment:  \newfloat{foo}{htb}{bar}[chapter]   The package however can be used for articles, books, ... Since not all of these environments have the concept of chapter, on gets a No counter 'chapter' defined. exception.  How can I check if the chapter counter is defined?


Why didn't Sauron become invisible while wearing the One Ring?

I'm curious as to why Sauron is the only being/person shown wearing the One Ring who does not become invisible?   Isildur, Gollum, Bilbo, Frodo, and Samwise all become invisible while wearing the One Ring.  Why didn't Sauron become invisible while wearing the one ring?  I became interested after reading Pearsonartphoto's question asking what effect wearing the One Ring would have had on .


jQuery Fire a custom event on table when new rows are added

I am trying to trigger a custom event when new rows are added to the table. Below is the code I am using but the event is not firing.   <!DOCTYPE html>
first div
                              What am I doing wrong. The table and its rows are dynamically added


How to strip a listing of all (line and block) comments without leaving white space?

I'm looking for an easy and robust way to strip all the comments from a listing. My approach (passing \@gobble to the commentstyle key) correctly removes all the one-line comments and block comments. However, the white space left behind by by block comments remains, creating useless gaps in my listing. See the screenshot below (the red rectangle is my emphasis). Any idea?    \documentclass{article}  \usepackage{xcolor} \usepackage[T1]{fontenc} \renewcommand{\ttdefault}{pcr} \usepackage{listings}  \makeatletter \lstset% {%   basicstyle   = \ttfamily,   morecomment  = [l]{//},   morecomment  = [s]{/*}{*/},   frame        = single,   commentstyle = \itshape\color[gray]{.5},   rulecolor    = \color{black},   breaklines, } \makeatother  \usepackage{filecontents} \begin{filecontents*}{sample.c} #include <stdio.h>  /*  block comment taking up white space */ main() {     float fahr, celsius;     float lower, upper, step;     lower   = 0;    /* lower limit of temperature scale */     upper   = 300;  /* upper limit */     step    = 20;   /* step size */     celsius = lower;     printf("\nCelsius\tFahr\n");     while (celsius <= upper)        {         fahr = (9.0/5.0) * celsius+32.0;         printf("%3.0f\t%6.1f\n", celsius, fahr);         celsius = celsius + step;     } } \end{filecontents*}  \begin{document} \makeatletter \lstinputlisting[caption={with comments}]{sample.c} \lstinputlisting[caption={without comments},commentstyle={\@gobble}]{sample.c} \makeatother \end{document}


I'm using Ubuntu 12.04. And can any one please tell me what difference between Ubuntu 12 and 13 and what version of Ubuntu is better. Why?   Thanks.


Prove that $x\sqrt{1-x^2} \leq \sin x \leq x$

Use the mean value theorem to prove that if $0 \leq x \leq 1$, then $$x\sqrt{1-x^2} \leq \sin x \leq x$$ The theorem guarantees the existence of a point, but not an inequality, so I don't know how to begin.


"Error processing package" - apt upgrade cannot run due to package configuration errors

I know it has been asked many times before but none of those solutions helped me.  Every time I am running sudo apt upgrade I get this error.  dpkg: error processing package systemd (--configure):  installed systemd package post-installation script subprocess returned error exit status 127 Errors were encountered while processing:  systemd E: Sub-process /usr/bin/dpkg returned an error code (1)   And sudo dpkg --configure -a returns     Setting up udev (237-3ubuntu10.28) ... /var/lib/dpkg/info/udev.postinst: 108: /var/lib/dpkg/info/udev.postinst: addgroup: not found dpkg: error processing package udev (--configure):  installed udev package post-installation script subprocess returned error exit status 127 Setting up systemd (237-3ubuntu10.28) ... /var/lib/dpkg/info/systemd.postinst: 123: /var/lib/dpkg/info/systemd.postinst: addgroup: not found dpkg: error processing package systemd (--configure):  installed systemd package post-installation script subprocess returned error exit status 127 dpkg: dependency problems prevent configuration of libnss-systemd:amd64:  libnss-systemd:amd64 depends on systemd (= 237-3ubuntu10.28); however:   Package systemd is not configured yet.  dpkg: error processing package libnss-systemd:amd64 (--configure):  dependency problems - leaving unconfigured dpkg: dependency problems prevent configuration of libpam-systemd:amd64:  libpam-systemd:amd64 depends on systemd (= 237-3ubuntu10.28); however:   Package systemd is not configured yet.  dpkg: error processing package libpam-systemd:amd64 (--configure):  dependency problems - leaving unconfigured Errors were encountered while processing:  udev  systemd  libnss-systemd:amd64  libpam-systemd:amd64   I don't think it's safe to remove systemd package all together. Any help is appreciated and I am on Ubuntu 18.04.


Infinite cartesian product from Herbert Enderton's Elements of set theory

I am reading Enderton's book  and I am having hard time understanding Infinite cartesian product section in which he define's product of $H(i)$'s.   Could you please explain in other simple words or by giving an example.  PS : I am a self learner  Thanks.


Tag badges are re-awarded for some users

Across the network, users are reporting cases where tag badges are re-awarded:   (Role-playing Games)  (Mathematics)  (Spanish Language)  (Arqade)  They basically lose all their tag badges, and then get them all back at once:


I'd like to get rid of the OneDrive option from the navigation panel of File Explorer. Preview-era articles I've found recommend registry tweaks, which is rather inelegant, and I'm hoping there is a better way to remove it.


What to do when a Windows Update (KB4480970) breaks your computer?

KB4480970 got installed on my system last night and now I'm no longer able to access files via SMB shares. Apparently this is a .  I restored my system to a previous restore point and the issue appears to be resolved, but in general what should I do in these situations? Will my system try to reinstall KB4480970 tonight? Do I just need to disable automatic updates? If so then should I disable them until perpetuity? If not then how do I know when I can turn them back on?


App crashes when the popup window is called

The popup window has to be shown when the app is started. The function that calls the popup window is located in the OnCreate() method. When I start debugging the app it constantly crashes.      public void ShowPopup() {         dialog.setContentView(R.layout.mainactiv);        dialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));        dialog.show();     }   And this is the error message:  java.lang.RuntimeException: Unable to start activity ComponentInfo  Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.app.Dialog.setContentView(int)' on a null object reference


How to write Javascript recipe.components.sort((a, b) => (a.components ? 1 : 0) - (b.components ? 1 : 0)) in Python?

I have translated a program from javascript to python 3.9 and I am only missing sorting the result, but I just can't get any further. The list consists of dicts that has an id "components", which is itself a list. recipe.components.sort((a, b) => (a.components ? 1 : 0) - (b.components ? 1 : 0))  If i understood the java code correctly, then all elements (a.components) that are an empty list should be at the beginning and all that have elements in their list should be at the end, but that's the small problem, because you can reverse it with .reverse() anyway. recipe.components = [{     "id": 123,     "components": [{"id": 1, "components": []}] }, {     "id": 124,     "components": [{"id": 2, "components": []}, {"id": 3, "components": []}] }, {     "id": 125,     "components": [] }, {     "id": 126,     "components": [{"id": 1, "components": []}] }]  Does anyone know how to write this most elegantly in Python? --- Edit --- I solved it like this: recipe["components"].sort(key=lambda a: 1 if a.get("components") else 0)


Development with git branches/ gitflow and new modules

I wonder if somebody found a solution for the following issue related to Drupal 8 development with Git branches:   You work on a new feature in a local feature branch for that you activate a contributed module or you write a custom module. This maybe delivers an own entity type and therefore creates a table after installing Meanwhile you need to fix a bug -> you change to a newly created bugfix branch which starts from the current dev branch After checking out the bugfix branch you import the current configurations to have the current active configuration of the branch -> the module you installed in feature branch is not activated anymore, the files of this module do not exist in the current bugfix branch You do your bugfixing and merge ths bugfix branch into develop branch. you change to your feature branch. To bring your local Drupal project to the status of this branch again you will import the configurations again   And here it comes to an exception: the table already exists in your database. When doing a drush cim it stops every following processing and you need to restart drush cim to import any further configurations.  Who does work with different feature branches and found a solution during development process to deal with this kind of situation?


Preventing Append_management from adding target to Table of Contents?

I am using ArcGIS Desktop 10.2.   I have a script that successfully converts a .csv into an already-existing feature class by first truncating the feature class table and then using the following line to replenish the table with the new data from the first parameter, "source" (an XYEventLayer).  arcpy.Append_management(input, target, "NO_TEST", mapping)   The destination feature class ("target") already exists in the TOC, within two group layers.    But every time I run the script a new duplicate layer appears at the top of the Table of Contents.  I'm 99% sure this is being done by the Append_management tool although  doesn't mention this behavior.  How can I prevent the Append_management tool from adding its output ("target") to the TOC?