Empty data converts to {1/1/0001 12:00:00 AM}

I have model with id and date. Then I make it angular.toJson and send to server. The problem is in that: if my date is empty, model's date field on server shows as {1/1/0001 12:00:00 AM} but not null. How to solve this? I need null.  Here is angularjs controller where my function calls   $scope.filterModel = function (filter) {     postService.getFilteredByUserId($scope.bindModel, angular.toJson(filter)); };   Here is my server function that gets this model  [HttpPost] public IEnumerable<TimesheetModel> FilterModel(TimesheetFilterModel filter) {     return TimesheetService.FilterTimesheetListByFilter(filter); }   Here is model:  public class TimesheetFilterModel {     public int      UserId { get; set; }     public DateTime DateFrom { get; set; }     public DateTime DateTo { get; set; }     public int      TicketType { get; set; } }


How to concatenate a std::string and an int

I thought this would be really simple, but it's presenting some difficulties. If I have std::string name = "John"; int age = 21;  How do I combine them to get a single string "John21"?


Root of continuous function using Rolle's Theorem

$$f(x)= 1 + e^x\cos(x)$$   $$g(x)= 1 + e^x\sin(x)$$      Show that there is at least one root of $g$ between two roots of $f$   How do I start to answer this question and do I need to use Intermediate Value Theorem?


I am an amateur in learing programming in Python. Recently, I found a question on local variable for functions. Here is my sample code:  """ Scenario-1: """ a=4  def g(x):     #global a     #a=a+2     print(a)     return x+a   when I type g(2) in console (I am using Enthought Canopy), it returns:  4 6   ----nothing wrong. then I change the code to (delete "#" before "a=a+2"):  """ Scenario-2: """ a=4  def g(x):     #global a     a=a+2     print(a)     return x+a   then re-run the code and type g(2), it shows:  *UnboundLocalError: local variable 'a' referenced before assignment*    My 1st question is: in Scenario-1, as I return x+a, why there is no referenced before assignment error?  Additionally, I change the code to:  """ Scenario-3: """ a=4  def g(x):     global a     a=a+2     print(a)     return x+a   then I re-run the code and type g(2), it returns:  6 8   ----nothing wrong. BUT, when I type a and enter in console, it returns:  4   Here comes my 2nd question, on global variable:  as I declare a to be global in function g(x), why variable a did not change to 6=4+2 (according to a=a+2)? I thought when variable a is so-called "global", the value changing in function inside will lead to the changing outside of the function, which is in main(). Am I wrong?  Above are my two basic questions. Thank you very much!


Does quantum mechanics have any insight into why and how photons get adsorbed into atoms?

Relativity holds that energy and mass are equivalent via the equation $E=mc^2$ also I know in quantum mechanics we talk about electrons jumping into bigger orbitals if they gain just the right amount of energy, or electrons emitting light and cascading down into lower energy levels, as in the laser phenomenon of population inversion. Either way the energy of the electrons is changing which changes its relativistic mass.  Back in relativity we have nuclear reactions converting mass into radiation and vice versa. So both theories seem to be talking about the same thing. Some how or other the massless photon is able to condense into ordinary matter. What I'm interested in is what that looks like. Is matter just a bunch of dead photos? Are they perhaps waves that somehow got tangled up and they are interfering with each other photon in the nucleus so that they sort of orbit each other?  Another thing that's always confused me is when to use what theories where. My chemistry teachers seem to switch back and forth arbitrarily between relativity and QM to explain various phenomenon.


Exporting PNG Animation sequence in vertical column sprite Sheet

I made an animation of a wheel rotating which is 80 frames. Is there a way I can export my PNG sequence in a vertical sprite sheet, the PNG files stacked one on top of the other like the example I have provided? Thank you.


How to get QASM code from IBMQ experience

I am interested in retrieving the OpenQasm code of a quantum circuit, as it appears on IBM Quantum Experience. This is the code that the quantum machine actually runs. I used to be able to just copy the code from the results tab, but I seem to not be able to do that anymore. Is there any way to retrieve said Qasm code? Thank you in advance.


I have downloaded Ubuntu 14.04 and wanted to try some OpenGL programming. My laptop has switchable graphics technology (Intel HD Graphics 4000 and AMD Radeon HD 8570M). I thought that it'd be better to install proprietary drivers and take advantage of OpenGL 4+ so first I installed the drivers by typing sudo apt-get install fglrx-updates, then I rebooted my pc. However, after boot, low-graphics error came up instead of login screen.  I didn't give up and tried searching google on my other computer. I tried almost everything possible, yet it still looks like my graphics is not being recognized.  It's worth noting that I have linux-headers installed and am using 64bit version of Ubuntu. Also, when I uninstall the fglrx driver, everything works fine again.  Here's what I already tried:   Reinstalling the drivers (complete purge). Entering low-graphics mode and typing amdconfig --initial. Installing the newest drivers drivers from amd.com (I also tried beta drivers; no luck). I switched LightDM to GDM, still no luck (it completely broke my Ubuntu installation).   Thank you for any suggestion.  EDIT: By reading some log files I came to a conclusion that the greeter fails to start. I just don't know why.  EDIT 2: I installed GDM once again. Now it boots to console without showing any error. I tried to log in and type startx and it says Caught signal 11 (Segmentation failed).


This question is related to this:  We have $P_3=P_2\cdot P_1$,for three non-zero polynomials. The degree of each polynomial is at least 1.  Question: Does $P_1$ overlap $P_3$ over more than one point?    By overlap I do not mean intersect. Instead, I mean a part of the polynomials can lay on each other over more than one point. edit: $P_1\neq P_2$


Help? Dual boot REPAIR (Windows 10 & Ubuntu 18.04.1)

Please assist? Original OS Windows 10. 2nd OS Ubuntu 18.04.1. Both installed on a separate SSD from storage/documents HDD.   Worked perfectly until a week ago, but upon waking I could no longer boot to Windows, only Ubuntu. So apparently something is wrong with GRUB2, but I've no idea what. Please speak as if I know nothing (mostly true re boot repair, OS problems)  Thank much!


Do HTML errors affect search impressions/ traffic?

Do HTML errors affect search impressions? (The errors shown in red when right-clicking the bottom-right-hand corner of a website.) And can correcting them eventually improve traffic?  I had lots of little HTML errors on my site (all pages) and I fixed them all on the 11th Dec. I've been told that this should increase the search impressions of my pages. Since then the impressions haven't gone up, but maybe it is a matter of time? It's been 2.5 weeks now.  I believe many (though not all) of my pages are otherwise well keyword-targeted.  Thank you!


Why area of rectangle is less than its integral

Let us suppose we have a triangle with base $j$ to $j-1$ and height of $1/j$ for $j=2,...,n$. Then, $$\frac{1}{j}(j-(j-1))\lt\int_{j-1}^{j}\frac{1}{x}dx$$ Why $\frac{1}{j}(j-(j-1))\lt\int_{j-1}^{j}\frac{1}{x}dx$?


Does a hot object in space/vacuum gets cold? how?

I'm trying to understand QM and many stuff gets in conflict in my head. Black body radiation means a hot object produces light in certain frequencies. Meaning it's losing energy.  Yet they talk about Thermal Equilibrium, which means the temperature of the object is constant. But can it? if it's losing energy how can an object have constant temperature.  Even in space an hot object would lose energy by producing photons, right? No?


Generating a self-signed cert with openssl that works in Chrome 58

As of Chrome 58 it no longer accepts self-signed certs that rely on Common Name: $3ACanary%7Csort:relevance%7Cspell:false  Instead it requires using Subject Alt Name. I have been previously following this guide on how to generate a self-signed cert:  which worked great because I required the server.crt and server.key files for what I'm doing. I now need to generate new certs that include the SAN however all of my attempts to do so have not worked with Chrome 58.  Here is what I've done:  I followed the steps on the above mentioned Heroku article to generate the key. I then wrote a new OpenSSL config file:  [ req ] default_bits        = 2048 distinguished_name  = req_distinguished_name req_extensions      = san extensions          = san [ req_distinguished_name ] countryName         = US stateOrProvinceName = Massachusetts localityName        = Boston organizationName    = MyCompany [ san ] subjectAltName      = DNS:dev.mycompany.com   Then generated the server.crt with the following command:  openssl req \ -new \ -key server.key \ -out server.csr \ -config config.cnf \ -sha256 \ -days 3650   I'm on a Mac, so I opened the server.crt file with Keychain, added it to my System Certificates. I then set it to Always Trust.  With the exception of the config file to set the SAN value these were similar steps I used in prior versions of Chrome to generate and trust the self-signed cert.  However, after this I still get the ERR_CERT_COMMON_NAME_INVALID in Chrome 58.


Whether range of matrix $A^TA$ is the same as that of $A^T$

I cannot ensure whether column space of $A^TA$ is the same as $A^T$, if it is, how to prove?


Are the PS Plus exclusive skin's available on my account if I am not the consoles PS Plus subscriber?

I have  been trying to get the PS Plus exclusive skin for Fortnite on my account but I don't have PS Plus. Although one of the accounts on the PS4 has PS Plus, so can I still get the skin on my account if I go to the PlayStation store or can I download it on the account that has PS Plus and it will show up on my account?


How do you compare multiple properties of objects within an ArrayList using the Comparable Interface?

I need to sort Rectangle objects in my ArrayList list1 by their corresponding properties: height,width, and topCorner(Point). I am able to sort the list when evaluating one property.   How can I set up my compareTo method so that it first attempts to sort the objects in the list by height, then by width(if all object heights are equal), and finally bytopCorner(if all object heights and widths are equal)?  public class Point implements Comparable<Point> {  private int x; private int y;  public Point(){     this(0,0); } public Point(int x,int y){     this.x=x;     this.y=y; } public int getX(){     return x; } public int getY(){     return y; } public int compareTo(Point pt){     if(x==pt.x){         return y-pt.y;     }     else{         return x-pt.x;     } } public String toString(){     return "("+x+", "+y+")"; } } class Rectangle implements Comparable<Rectangle> {  private int height; private int width; private Point topCorner;  public Rectangle(int x,int y,int height,int width){     this.height=height;     this.width=width;     this.topCorner=new Point(x,y); } public int getHeight(){     return height; } public int getWidth(){     return width; } public Point getPoint(){     return topCorner; } public int compareTo(Rectangle rect){     if(height!=rect.height){         int compareHeight=((Rectangle)rect).getHeight();         return this.height-compareHeight;     }     else if(width!=rect.width){         int compareWidth=((Rectangle)rect).getWidth();         return this.width-compareWidth;     }     else if(topCorner!=rect.topCorner){         Point comparePoint=((Rectangle)rect).getPoint();         return this.topCorner-topCorner;     }     else{         System.out.println("// ERROR BRO // ERROR BRO //");     }     return 0; } public String toString(){     return "(H:"+height+", W:"+width+", P:"+topCorner+")"; } }   ===========================================================================  public class RectangleComparable { public static void main(String[]args){     Random rn=new Random(21);     ArrayList<Rectangle> list1=new ArrayList<>();     for(int index=0;index<10;index++){         int ran1=rn.nextInt(21), ran2=rn.nextInt(21),                 ran3=rn.nextInt(21), ran4=rn.nextInt(21);         list1.add((new Rectangle(5,ran2,ran3,ran4)));     }     System.out.println("KEY : H=height, W=width, P=point\n");     System.out.println("Unsorted List : \n"+list1+"\n");     Collections.sort(list1);     System.out.println("Sorted List : \n"+list1); } }   I'll go ahead and apologize if this is somehow a duplicate question. I looked around, but I didn't find anything that gave me a really direct answer (because I'm still a programming noob).


Yesterday I wrote a Thread addressing how my game loop ran (in java) and how it works.  My game loop works completely, and I know why, but now I just wan't to know how to calculate FPS (Frames Per Second) and print it out every second.  I got a response yesterday about this, but he/she explained it in words and I couldn't understand it.  If anyone could help me (with a code example? :D) that would be great.  Here is my game loop:          while (running) {          start = System.nanoTime();          update();         draw();         drawToScreen();          elapsed = System.nanoTime() - start;          wait = targetTime - elapsed / 1000000;         if (wait < 0) {             wait = 5;         }          try {             Thread.sleep(wait);         } catch (Exception e) {             Game.logger.log("ERROR! Printing Stacktrace...");              e.printStackTrace();         }      }   ALSO:  In my JFrame when ever I call setName(string) it never works/updates on the Frame - Link me to a thread?


How to find out the amount of hard drive space consumed by installed programs?

I was wondering if there is any way to see the total hard drive space used by any  program, after the installation has been completed?


I have 2 objects from the same type and i would like to shallow copy one state to the other. In C++ i have memcpy which is great. How can i do it in C#? The MemberwiseClone() is not good enough because it creates & returns a new object and i like to copy to an existing object. I thought of using reflection but i'm afraid it will be too slow for production code. I also thought of using one of the .Net serializers but i think they also create object rather than setting an existing one.  My Use Case:  I have a template object (class not struct) which needs to be updated by one of its instances (objects made of this template)  Any ideas?


Lebesgue integral of absolute value of sequence of functions

I am working on a problem$^{(*)}$ on Lebesgue integral looks like this:     Given that both $f_n$ and $f$ are integrable, $f_n \longrightarrow f$ a.e., and $\int|f_n| \longrightarrow \int |f|$. Show that    $$\int |f_n - f| \longrightarrow 0.$$   To me, the question "makes sense" since $\int |f_n - f| \longrightarrow 0$ implies $\lim_{n \to \infty} \int |f_n - f| = 0,$ and $|f_n - f|$ is approaching zero as $n$ is approaching infinity, therefore the integral is approaching zero. But I do not know how to say it mathematically.  Any help or hints would be very much appreciated. Thanks for your time.    (*) Richard F. Bass' , 2nd. edition, chapter 7: Limit Theorems, exercise 7.5, page 57.


Items on the ground clump together in stacks, so getting the number of entities doesn't give me the number of items there are. Is there a way to count the number of items instead of the number of item entities?


I have searched around and haven't found a specific answer to my question..  I am wondering the best practice for storing timestamp information.  Example: user1 logs in in Florida (-0500) at 3:00pm EST The admin logs into the system an hour later from California (-0800) at 4:00pm  I want the admin to see the log onscreen and see that user1 logged in 1 hour ago..  My brain is going nuts bc i feel that i am over complicating this..  I should be able to use UNIX time stamp and then adjust with the -0800 or -0300.  Do i store the users timezone offset in their profile information? Do i store the -0300 with the log entry.  Any input would be greatly appreciated!


For Oracle Database How to find when the row was inserted? (timestamp)

This has been asked many times, but is there any new methods to find out the time when the row was inserted in Oracle Database?  I have already tried to find out using ORA_ROWSCN. But its not accurate. It shows the updated date i believe and dose not show if the row is inserted before a long time.  The previous designers thought that its not necessary to include the Date added and Date updated columns when they were designing the Database.  This has caused a lot issues when it comes to analyzing the data and auditing.  Please help, this would make my day.   Thanks in Advance  :


why PHPMailer taking too much time to send email and also once it sent email , i got mail in spam

i want to send email using user's entered email address to my email address using PHPMailer and without SMTP. But it takes too much time to send email and once it sent email i got mail in spam instead of inbox. Below is my complete code-  <?php  session_start(); require_once 'class.phpmailer.php'; $mail = new PHPMailer;  $mail->From = $_POST['email']; $mail->FromName ='Contacted By : '.$_POST['fname'];  $mail->addAddress("dev5.veomit@gmail.com");   $mail->addReplyTo($_POST['email'], "Reply");  $mail->isHTML(true);  $mail->Subject = "Subject Text"; $mail->Body = "Name : ".$_POST['fname'].'
Email Address : '.$_POST['email'].'
Message : '.$_POST['msg']; $mail->AltBody = "This is the plain text version of the email content";  if(!$mail->send())  {     echo "Mailer Error: " . $mail->ErrorInfo; }  else  {     $_SESSION['sucess-email']='You Have Contacted Successfully.';     header("Location: https://m-expressions.com/test/voy/"); }  ?>   Please help me solve this problem and thanks in advance.


In Reddit, there is a section for posts that are heavily down/upvoted, making them "controversial." Why might this be a bad idea?


How to monitor only the last n lines of a log file?

I have a growing log file for which I want to display only the last 15 lines. Here is what I know I can do:  tail -n 15 -F mylogfile.txt   As the log file is filled, tail appends the last lines to the display.  I am looking for a solution that only displays the last 15 lines and get rid of the lines before the last 15 after it has been updated. Would you have an idea?


Please recommend pgrouting tutorials or workshops that are most current.  I ask because I just read a post that claims a tutorial is deprecated. (see osm2po vs osm2pgrouting: workshop post)  I am working through the pgrouting-workshop (http://workshop.pgrouting.org/) and find it mostly helpful.    The OS and environment here:  ubuntu 12.04, postgres 9.1, postgis 1.5.   While it may be unreasonable to ask that all deprecated tutorials be so marked, it would help if the date of authorship is included prominently in the header of all training materials, then newbies would know to expect some staleness.


Finite group is abelian if the representatives of its conjugacy classes commute

Let $G$ be a finite group and let $g_1 , g_2 ,...,g_r$ be the representatives of its conjugacy classes. If $g_i g_k=g_k g_i$ for every $i,k \in$ {$1,2,...,r$}, then prove that $G$ is abelian.     My original trial was to prove this in arbitrary subgroup of $S_n$ and using Cayley's theorem we can prove this easily, and the reason is we can take advantage of the fact that  if $\tau , \sigma \in S_n$, $$\sigma = (a_{11} ... a_{1 n_{1}})(a_{21} ... a_{2 n_{2}}) ... (a_{r1} ... a_{r  n_{r}})$$  then $$\tau \sigma \tau ^{-1} = (\tau(a_{11}) ... \tau(a_{1 n_{1}}))(\tau(a_{21}) ... \tau(a_{2 n_{2}})) ... (\tau(a_{r1}) ... \tau(a_{r  n_{r}}))$$  But this didn't give me any valuable results, so any hints which can be useful ?  I found a proof of this exercise , but I want to construct my own proof.  Any hints ?


Unable to save the Lead record since Company is a standard required field in salesforce before insert trigger

I am trying to copy the value of user selected Status value into the standard salesforce required Company field. Now, when I try to save the record on the object since I am not entering any value in the Company field, the record is not being saved. How do I solve this kind of issue? Any leads appreciated  trigger CopyStatusToTitle on Lead (before insert, after insert) {      List<Lead> leadList = new List<Lead>();     if(Trigger.isInsert){         if(Trigger.isBefore){             //process before insert               for(Lead l : trigger.New){                 l.Company = l.Status;              }          }else if(Trigger.isAfter){             //process after insert          }       } }


Overall 	 14	 2,277	 2,619,106,616	   Let's say we have that and I want the 2,277 in a string how would I cut it?


Prove that there exists an irreducible polynomial $f\in\mathbb{F}_p[x]$ of degree $2014$

Let $p$ be a prime and let $F=\mathbb{F}_p$.  Prove that there exists an irreducible polynomial $f\in F[x]$ with $\deg(f)=2014$.   Attempt:  Assume in contradiction that every polynomial $f\in F[x]$ of degree $2014$ is reducible. Let $f\in F[x]$. (My problem is to find a proper $f$ such that I will get a contradiction). There exist $g,h\in F[x]$ s.t. $$ F[x]\ni f(x)=g(x)\cdot h(x)$$ If we look at $f$ as an element in $\mathbb{Z}[x]$ then we get that there exists some $r\in\mathbb{Z}[x]$ s.t. $$\mathbb{Z}[x] \ni f(x)=g(x)\cdot h(x) +p\cdot r(x)$$


Do programs keep running on macos when user switches account?

I am wondering if programs keep running when users switch account, alas account is locked and another user account logs in. For instance, user Mike runs Photos (that will start curating pictures), then locks account and user Sue logs in to other account; will Photos instance keep running in Mike account in the background?


Number of unique outputs in hash function (SHA256) against all possible inputs

If I use SHA256 as a hash function, and I try all inputs starting from 0 to 2^256 (means all possible combination of 256-bit), then will it give me 2^256 unique output without any collision?      Or in other words, does 2^256 different inputs maps to 2^256 different output in SHA256?


Why can't I play songs downloaded on iOS 7?

I downloaded songs on my iPhone 5 with iOS 7 and the songs played fine yesterday. When I connected to iTunes, the songs became unavailable on my iPhone with a red square and red circle around the square. The songs also do not appear in iTunes. Please help??


Everything about a very disturbing movie Martyrs (2008)

After watching Martyrs (2008), I kept on thinking about the motive or the message behind that movie. My question is, why was the skin peeled off the entire body of that girl, and what did she tell to the old woman which led the woman to commit suicide?


Beamer goes to next slide instead of the target slide

I am a new user of Beamer presentation template and noticed that when I click on an entry from the ToC it goes to the next slide instead of the target one. However, when I open the pdf file in a pdf viewer such as Foxit and click on the bookmark it goes to the right slide. Why is this discrepeancy cause and is there a solution for it?


If $f(xy) = f(x) + f(y)$, show that $f(.)$ can only be a logarithmic function.

As the question states, show that the property exhibited can only be satisfied by a logarithmic function i.e no other family of functions can satisfy the above property.


Created user can access all databases in PostgreSQL without any grants

I must be missing something with regards to setting up PostgreSQL. What I'd like to do is create multiple databases and users that are isolated from each other so that a specific user only has access to the databases I specify. However, from what I can determine, any created user has access to all databases without any specific grants being given.  Here is what I do on an Ubuntu Server 12.04:   apt-get install postgresql sudo -u postgres createuser -DRSP mike1 (Specifying the password for the new user) sudo -u postgres createdb data1 psql -h localhost -U mike1 data1 (Specifying the password for the user mike1 to login)   It seems that new user "mike1" has no problem connecting to database "data1" and creating tables etc. And this without running any GRANT command at all (and the owner of "data1" is "postgres" since I didn't specify an owner in step 3). Is this really how it is supposed to work?  What I'd like to do is grant mike1 full access to data1 and then repeat this for more users and databases, making sure that the users only have access to one (or possibly several) databases of my choice.


Reputation out of sync on community wiki reversal

(274 reputation). Result of :     ** rep today: 0   ** rep this week (2014-04-20 - 2014-04-26): 0   ** rep this month (2014-04-01 - 2014-04-30): 5   ** rep this quarter (2014-04-01 - 2014-06-30): 5   ** rep this year (2014-01-01 - 2014-12-31): 328   ** rep from bonuses: 100   ** total rep 329 :)   reputation?recalc=true is disabled and displays the following message now:     We have disabled this ability because reputation should be in sync without any user intervention.   If it's not in sync for more than 5 minutes, it's a bug.  We need to investigate that bug and a recalc hinders fixing the actual cause.   Desync is caused by my question becoming a community wiki and then being reversed by a moderator several days later. I guess this is a known case of lost reputation, but none the less, either Reputation report needs to be fixed or reputation needs to be recalculated on CW status reversal.


Getting unit testing code into XML Comment

I am trying to comment an API (.Net) that I am exposing to a customer. I am doing this by using XML comments, and extracting via SandCastle.  This is all fine and dandy, however I have unittesting for the API, and thought the code from these would be good to place in the example tags.  So does anyone know of a good way to extract unit test code and place in the example tags? Or does anyone have better ideas?  Of course I redistribute the unit tests with the API, but it would be good to have them in the documentation.


Obscure show or movie from the 80's or 90's

Because I watched this when I was so young, I might have meld two shows into one.   these people have white jewels in the center of their fore heads to activate their powers, they place their index & middle fingers on their temples. I think they would glow as well I also remember a white, teenage girl with long brown hair as one of the main leads


reset counter when using \LTRfootnote from bidi package

I'm using xepersian package for my Persian job, and I would like the footnote counter to automatically restart from '1' for each page of my document when I using \LTRfootnote command, but footmisc package not work with this command.


How to upload csv files in lightning and create records from it

I want to upload csv file into lightning component and get the data from that csv file and need to create the records into custom objects using that csv.I am new to lightning.How can we achieve this using lightning.Any links for reference?


I have been trying to achieve a system which can scale a number down and in between two ranges. I have been stuck with the mathematical part of it.  What im thinking is lets say number 200 to be normalized so it falls between a range lets say  0 to 0.66 or 0.66 to 1 or 1 to 1.66. The range being variable as well.  Any help would be appreciated.  Thanks


For $R=\Bbb Z/m\Bbb Z$, show $ā∈R^\times ⟺\gcd(a,m)=1⟺ā$ is not a zero divisor in $R$

Hi guys can anyone help me with the following problem Let it be that $R=\Bbb Z/m\Bbb Z$. I must show the following equivalences $ā∈R^ˣ⟺\gcd(a,m)=1⟺ā$ is not a zero divisor in $R$ I already know that to solve this question i must show 3 or 4 separate (small) proofs of implications. For example "a∈Rˣ⇒gcd(a,m)=1" and "gcd(a,m)=1⇒a∈Rˣ". But I can't  solve any of them. I also tried to use "Bézout's identity" for some of the implications but I can't seem to get anywhere. Thanks for your help


Trouble understanding the usage of word "whose"

Consider the following sentence: Show that if matrix A has rank one, then A = x.y^T for some vectors x and y whose entries are nonnegative and sum to one. Is the interpretation that the nonnegativity refers to the elements in vectors x and y correct, or does the word "whose" somehow refer to the matrix A?


Anyone know how to edit the y tick? I want it in decimal form but the output gives tick in scientific notation. Thanks.       \documentclass[margin=5mm]{standalone}     \usepackage{tikz}     \usepackage{pgfplots}     \pgfplotsset{compat=1.13}     \begin{document}     \begin{tikzpicture} \begin{axis}[     ymin=0,ymax=0.12,     xtick={30,50,100,150,200,250,300},     ytick={0,0.02,0.04,0.06,0.08,0.10,0.12},     legend pos=north east,     x tick label style={rotate=90,anchor=east}     ]     \addplot[mark=*,mark options={fill=white}] coordinates {(30,0.018)(50,0.015)(100,0.0205)(150,0.0145)(200,0.016)(250,0.017)(300,0.014)};     \addlegendentry{a}     \addplot[dashed,mark=square*,mark options={solid,fill=white}] coordinates {(30,0.0165)(50,0.031)(100,0.0305)(150,0.0315)(200,0.0365)(250,0.0425)(300,0.043)};     \addlegendentry{b}     \addplot[dashdotted,mark=triangle*,mark options={solid,fill=white}] coordinates {(30,0.025)(50,0.025)(100,0.025)(150,0.025)(200,0.025)(250,0.025)(300,0.025)};     \addlegendentry{c}     \end{axis}     \end{tikzpicture}     \end{document}


What is a "Nested Quantifier" and why is it causing my regex to fail?

I have this regex I built and tested in regex buddy.  "_ [ 0-9]{10}+ {1}+[ 0-9]{10}+ {2}+[ 0-9]{6}+ {2}[ 0-9]{2}"   When I use this in .Net C#   I receive the exception  "parsing \"_ [ 0-9]{10}+ +[ 0-9]{10}+  +[ 0-9]{6}+  [ 0-9]{2}\" - Nested quantifier +."   What does this error mean? Apparently .net doesn't like the expression.  Here is the regex buddy so u can understand my intention with the regex...  _ [ 0-9]{10}+ {1}+[ 0-9]{10}+ {2}+[ 0-9]{6}+ {2}[ 0-9]{2}  Match the characters "_ " literally «_ » Match a single character present in the list below «[ 0-9]{10}+»    Exactly 10 times «{10}+»    The character " " « »    A character in the range between "0" and "9" «0-9» Match the character " " literally « {1}+»    Exactly 1 times «{1}+» Match a single character present in the list below «[ 0-9]{10}+»    Exactly 10 times «{10}+»    The character " " « »    A character in the range between "0" and "9" «0-9» Match the character " " literally « {2}+»    Exactly 2 times «{2}+» Match a single character present in the list below «[ 0-9]{6}+»    Exactly 6 times «{6}+»    The character " " « »    A character in the range between "0" and "9" «0-9» Match the character " " literally « {2}»    Exactly 2 times «{2}» Match a single character present in the list below «[ 0-9]{2}»    Exactly 2 times «{2}»    The character " " « »    A character in the range between "0" and "9" «0-9»   In short...  What is a Nested quantifier?


Book recommendations on physics of music and musical instruments

I am pursuing a degree in Mathematics and have a strong interest on music. I would like to understand the physical basis of how is music made. Does someone know some bibliography on this subject?


Regular expression to match non-ASCII characters?

What is the easiest way to match non-ASCII characters in a regex? I would like to match all words individually in an input string, but the language may not be English, so I will need to match things like ü, ö, ß, and ñ. Also, this is in Javascript/jQuery, so any solution will need to apply to that.


Why comment reply auto-completion feature (@) sometimes doesn't work?

Possible Duplicate:          Say, we've got an answer with some comments under it. Sometimes when I want to reply to one of the comments, I can easily refer to the comment author printing @ and starting to enter the author's name, that is autocompleted for me. But sometimes (if only one person gave comments or not...) I'm not suggested with any variant. Why is it so? On what terms does it depend?


I want to select all contents of a file and copy it to google chrome. I have tried shift-ctrl-c but it isn't working.


I create a Heap class which uses E general type generics extends from Comparable class. In the isEmpty method it checks whether the first element is empty or not.   But when I implement it, a NullPointerException occurs at isEmpty and add methods. How can I fix it ?  public class Heap<E extends Comparable<E>> { private E[] heapArr ; private int size = 3 ;  public Heap(){  } public Heap(E[] a){     this.heapArr = a;     size = a.length; } public boolean isEmpty(){     if(heapArr[0] == null)         return true;     else     return false; } public void add(E element){     if(isEmpty()){         heapArr[0] = element;     }     else{     int parent = (size-1)/2;     while((int) element > (int) heapArr[parent]){         heapArr[parent] = element;         parent = (parent-1)/2;     }     } }  public E remove(){      heapArr[0] = heapArr[size];      size = (size - 1);       int x = 0;      TricklingDown(heapArr, x);     return heapArr[0]; } public int max(E e1, E e2){     if((int) e1 > (int) e2){         return (int) e1;     }     else          return (int) e2; } public void swap(E e, int x){     heapArr[x] = e;      } public int TricklingDown(E[] heapArr1, int x){      int leftChild = (2*x +1);     int rightChild = (2*x +2);     int largerChild = 0;      while((int) heapArr1[x] < (int) heapArr1[leftChild] || (int) heapArr1[x] < (int) heapArr1[rightChild]){          largerChild = max(heapArr1[leftChild], heapArr1[rightChild]);         swap(heapArr1[x], largerChild);          x ++;      }     if(largerChild == leftChild){         return leftChild;     }     else          return rightChild;  }  }


Enter Croatia first (before Schengen zone) with dual-entry Schengen visa?

I am an Indian citizen and will be traveling to Croatia in a few days. I already have a multiple entry Schengen visa which is valid for the dates of my Croatia trip. However, my first destination from India will be Dubrovnik (Croatia) and after that I will depart for Schengen area (Austria).  Would I be able to enter Croatia before entering the Schengen zone?


Can I target a tapped creature for “tap target creature, target creature doesn’t untap during its controller’s untap step.”

I have two cards that I’ve had disputes with. 1: Shipbreaker Kraken 2: Archipelagore The Kraken says “When Shipbreaker Kraken becomes monstrous, tap up to four target creatures. Those creatures don’t untap during their controllers’ untap steps for as long you control Shipbreaker Kraken.” Can I still target an opponents creature if that creature is already tapped? I’m going off the way it’s worded, I know I can’t do anything impossible (like tap an already tapped creature), but can I still TARGET the creature and the effect happens? Same question with Archipelagore. It says “Whenever this creature mutates, tap up to X target creatures, where X is the number of times this creature has mutated. Those creatures don’t untap during their controllers next untap step.” Can I still TARGET a tapped creature that is already tapped? Scenario: I mutate Archipelagore so it’s effect happens. My opponent has a creature that is tapped (they attacked last turn). Can I target that creature with Archipelagore’s effect so it doesn’t untap during my opponents next untap step? I’m going off of specific wording and the order of the effect. And if you have any up to date rules that would help as well. Thanks!


Meaning of "by" when used with dates - inclusive or exclusive

If, in a contract fr example, the text reads: "X has to finish the work by MM-DD-YYYY", does the "by" include the date or exclude it?  In other words, will the work delivered on the specified date violate the contract?


Why does my browser think that https://1.1.1.1 is secure?

When I visit , any web browser I use considers the URL to be secure.  This is what Google Chrome shows:    Normally, when I try to visit an HTTPS site via its IP address, I get a security warning like this:    From my understanding, the site certificate needs to match the domain, but the Google Chrome Certificate Viewer does not show 1.1.1.1:     says:     No - we no longer accept certificate requests for either intranet names or IP addresses. This is an industry-wide standard, not one specific to GoDaddy.   (emphasis mine)  And also:     As a result, effective October 1, 2016, Certification Authorities (CAs) must revoke SSL certificates that use intranet names or IP addresses.   (emphasis mine)  And:     Instead of securing IP addresses and intranet names, you should reconfigure servers to use Fully Qualified Domain Names (FQDNs), such as www.coolexample.com.   (emphasis mine)  It's well after the mandatory revocation date 01 October 2016, yet the certificate for 1.1.1.1 was issued on 29 March 2018 (shown in the screenshot above).    How is it possible that all the major browsers think that  is a trusted HTTPS website?


Need help identifying short story about retired military colonel who fought war at end of time

I read this story in an anthology in the eighties or early nineties.  It was about an old man who lived outside a western-like town, though that might have just been how I imagined it.  He goes to town and some ex-military thugs are there causing problems.  Flaunting some odd interdimensional military tech of some sort.  He doesn't want to intervene as doing so would be bad but in the end he must.     By intervening, his military identity is revealed and that causes him (some paradox or causality law) to have to go back and fight the war again.   The war is at the end of time or the universe.  The man is maybe a colonel of the sky something... Not much to go on; I have been searching my collection and wracking my brain for years trying to recall the story.


Duplicate question etiquette: to delete or not to delete?

Let's say I'm a good Stack Overflow citizen: I have a question, I search on SO and on google to see if someone's asked the same thing, and I can't find anything that shows up, so I go ahead and post a well-written question on SO. Then later it gets closed, because it's a duplicate question for something that I wasn't able to find on my initial search. Great, the system worked.  Is there ever a case where I should delete the question I posted? Why or why not? Do duplicate questions cause much resource bloat for the site?


Object passed as parameter loses changes when modified within method (java)

Here is my function:     public boolean loadPaper(Paper paper) {     boolean success = false;     try {         FileInputStream file_in = new FileInputStream(getDbFileName(paper));         ObjectInputStream in = new ObjectInputStream(file_in);         paper = (Paper)in.readObject();         in.close();         file_in.close();                  success = true;     }     catch (IOException | ClassNotFoundException i) {         i.printStackTrace();     }     return success; }  When I pass a Paper object to the loadPaper method, the method de-serializes the Paper in question and stores it successfully in "paper." However, when the method returns to the calling method, the "paper" object passed in as a parameter no longer stores the data that was loaded. For example, after this code executes: Paper paper = null; loadPaper(paper);  "paper" no longer stores any data, even though it did up until the end of the loadPaper method. Any idea why?


How to make applications launch in desired workspace

I'm working in one workspace. I switch to a different workspace and launch Firefox (by clicking its button in the sidebar). I switch back to the original workspace while Firefox is launching.   I wanted Firefox to run in the alternate workspace. But it opens its window in the original one.   Seems like there should be a way for apps to notice which workspace they're being launched into, and honor that choice.


I think this question would be with complicated methods in singularity or other kind of methods. I need to solve the integral $$\int_0^\infty\frac{\cos(ax)-\cos(bx)}{x}dx$$ Thanks a lot.


Which version of Ubuntu will work on my PowerPC?

I'm using iMac PowerPC G5 1.8 GHz, 1GB RAM, 160GB HDD, and 10.5.4 Leopard OS.  I want to run Ubuntu on my iMac. Please can anyone tell me which version will run in my system?


A blend file I am working on has developed two quirks, but I'll deal with just the camera issue here. Basically, the 4 sided 'cone' of the camera is invisible. The 'lens' area is visible as is the origin point, the cone with the triangle on top is gone. I can move the camera, but when doing so the lens square and origin point vanish, so the only way to navigate is through camera view. Note that this is file specific, and resetting prefs to default won't work. This is not occurring in any other blend file. The image below is what I see in the .blend in question;  and this is a different .blend showing the camera properly visible.  I am sort of assuming I have just hit some weird key combination by mistake, but I can't seem to recover it. Any thoughts? Oh, and it IS visible in the collections stack or the lens frame would also be gone. Cheers


Adding feature class to Map in CURRENT project using ArcPy in ArcGIS Pro?

I want to add a feature class within a Geodatabase to a map in ArcGIS Pro (1.4.1) using arcpy. I am converting some python code from ArcGIS Desktop to ArcGIS Pro.   This issue is very similar to:    and      However, instead of adding a feature class (or layer) to a map using the Python Window I am doing this from a  Script within a Toolbox. I have included a code snippet below.  lyrTest = r"C:\data\test.gdb\Layer1"  aprx = arcpy.mp.ArcGISProject("CURRENT") aprxMap = aprx.listMaps("MainMap")[0]  lyrFile = arcpy.mp.LayerFile(lyrTest) aprxMap.addLayer(lyrFile)   I get the following error message:  Traceback (most recent call last): File "C:\data\AddLayers.py", line 5, in <module>     aprxMap.addLayer(lyrTest) File "c:\users\user\appdata\local\programs\arcgis\pro\Resources\arcpy\arcpy\utils.py", line 191, in fn_ return fn(*args, **kw) File "c:\users\user\appdata\local\programs\arcgis\pro\Resources\arcpy\arcpy\_mp.py", line 1048, in addLayer return convertArcObjectToPythonObject(self._arc_object.addLayer(*gp_fixargs((add_layer_or_layerfile, add_position), True))) ValueError: C:\data\test.gdb\Layer1 Failed to execute (AddLayers).


Can interfaces have static methods or java class stati'fy interface method?

The following is allowed:-  public interface JustImplementMe {    public void ClimbMountain(); }   The following is not allowed:-  public interface StaticMethodInterface {    public static void Climb(); }   The following is allowed:-  public class Classic implements JustImplementMe {    public void ClimbMountain()    {     } }   The following is not allowed:-   public class ClassicMusic implements JustImplementMe      {       public static void ClimbMountain()       {         // static method cannot hide the instance method in JustImplementMe       }    }     Why is it so? Thanks.


I am having difficulties with getting my AMPscript to resolve in the sender profile. I can't get both values to populate for the Sender Name. The from email doesn't resolve at all and I'm not sure if it's because I'm putting in the email address directly with an @ symbol. %%=IIF(EMPTY(AttributeValue("OwnerID")), "Bill", AttributeValue("LeadFirstName") AttributeValue("LeadLastName"))=%%  Here is the from email: %%=IIF(EMPTY(AttributeValue("OwnerID")), "bill@domain.com", AttributeValue("OwnerEmail"))=%%  I want to create dynamic sender profile with a dynamic from name and a dynamic from email with logic that says, if this field has a value, use fields FirstName and LastName. If it is blank, use "Bill".


I don’t know any man that is present here.   I don’t know any man who is present here.      Which is correct? What is the difference in meaning between these two sentences?


How can I control the permissions an app has if I am on a rooted android?

Some apps ask for a ridiculous amount of permissions. Android tends to be you accept all the permissions and use the app or you don't accept all and don't use the app. This is different from how IOS handles permissions. For IOS, you can selectively allow permissions like location, notifications, photos, bluetooth, camera, etc. How can I do this on android. I don't care if it breaks certain apps. Sometimes their is a descent app that just ask for an overwhelming amount of permissions.   Any ideas? Android 5.1.1! No custom ROM. Don't have xposed? But I can install it if I need too.


How to prove that when $m$ is not a full power of any natural number, then $m^{(1/2) }$ is irrational   I have tried this but got nothing;  $\sqrt{m}=\frac{p}{q}$ were $p,q$ are natural and $\gcd(p,q)=1$;


In counting degrees of freedom of a linear molecule, why is rotation about the axis not counted?

I was reading about the equipartition theorem and I got the following quotations from my books:  A diatomic molecule like oxygen can rotate about two different axes. But rotation about the axis down the length of the molecule doesn't count. - Daniel V. Schröder's Thermal Physics. A diatomic molecule can rotate like a top only about axes perpendicular to the line connecting the atoms but not about that line itself. - Resnick, Halliday, Walker s' Fundamentals of Physics.  Why is it so? Doesn't the rotation take place that way?


Hard wiring a 4-wire oven to 3-wire outlet?

I am replacing an old 4-wire oven with a new Kitchen Aid 4-wire oven. I have 3 wires in the outlet box (black, white, bare (ground)).  The old oven was connected the following way: From the oven the white wire and the bare (ground) together were connected to the bare (ground) in the box. The black wire from the oven was connected to the white wire in the box and the red wire from the oven was connected to the black wire. There was a lot of black electrical tape wrapped around the white wire in box about 3 inches from the connection point. Not sure what that means? I was planning to connect the same way, but see some instruction on the internet to connect the same way, except black goes to black and white goes to red. Confusing and  conflicting information and not sure which is correct way. Or does it not matter since each wire, black and the white are hot each supplying 110V for a total 220V?


Is solving all of the exercises in a textbook a good idea? I'm particularly concerned with textbooks on mathematics. I have this obsession that I should solve all of the problems that a textbook has. It takes a lot of time and energy but usually I'm satisfied with the end result being me having a better understanding of that particular subject.   Any similar experience of this sort? How's this going to work in the long-run?


"30 day span", "30-day span", or "30 days span"

As in, "for each 30-day span, a late fee will be charged." I think the hyphenated version looks best, but is there some sort of authoritative word on that in a style guide?


Windows 10 scans and repairs drive after using Ubuntu 15.10

I have installed Ubuntu in UEFI in parallel with my Windows 10.  It's not a major problem.  My system easily boots to Ubuntu but whenever I reboot to Windows after Ubuntu, it shows  scanning and repairing the drive: 100% done   (note: Ubuntu is installed on this drive) and it takes longer to boot than from Windows to Windows only.


I know there are 32/64 bit OS in the market. Q1-> But what does this bit mean actually ? Q2-> What is the lowest bit OS and highest bit OS ?


What is the difference between "Main (String[] args)" and "Main(string[] args)" in C#

What is the difference between   public static void Main (String[] args)   and   public static void Main (string[] args)   in C#? I am using SharpDevelop 4.3.1 as the development environment.   If I am using string it is highlighted in red but when I am using String it is highlighted in black. Checking online I found out that both String and string are the same, if so why are they highlighted differently?


Is there way to sync the shell yank buffer and the clipboard?

In a terminal I copy a line by Ctrl+a and Ctrl+k. I want to copy the text into clipboard when another window become active so that I can use the text another application, like a text editor or a browser.  Is there way to do it?


For(each) loop twice-populates a combobox

I've built a combobox that is dynamically populated depending on the contents of another combobox, and so on. I've decided, although it's a bit terrible, to experiment with iterating through the contents of the source array when populating the target combobox. However, although this results in combobox contents, they are repeated. I've stepped through the code, and the array is only being iterated through once.    private JComboBox regBuildingSelectBox; ...  String[] siteSelectStrings = {"Site", "London", "Long Island"};     JComboBox regSiteSelectBox = new JComboBox(siteSelectStrings);     regSiteSelectBox.addItemListener(new ItemListener() {         public void itemStateChanged(ItemEvent arg0) {             getDropDownVariables gddv = new getDropDownVariables();             for(String s:                    gddv.buildingSelectList                             (regSiteSelectBox.getSelectedItem().toString()))             {                 regBuildingSelectBox.addItem(s);             }         }     });     regSiteSelectBox.setBounds(24, 336, 282, 20);     contentPane.add(regSiteSelectBox);       regBuildingSelectBox = new JComboBox();      regBuildingSelectBox.setBounds(24, 367, 282, 20);     contentPane.add(regBuildingSelectBox);   The code containing the arrays is as follows:  public class getDropDownVariables {      public String[] buildingSelectList(String site)     {         switch (site)         {         case "London":             return new String[]  {"Building", "Harvell",                                  "LYNX Complex", "Caroline", "Salters"};         case "Long Island":             return new String[] {"Building", "Phillips", "Pascal"};         }         return new String[] {"Failed to populate buildings"};     }   And the result:


Plunker should be "banned" just like jsFiddle

Plunker () seems to be a more feature-rich alternative to  (it seems to be especially popular with AngularJS developers, probably because you can "host" multiple files there, which is useful for templates). It's a very good site and certainly useful.  But since we often ended up with incomplete questions, because code was only posted on jsFiddle, we ended up  with jsFiddle links that don't also contain code.  And I simply think that Plunker should share the same fate.  Some examples:


How do you play a sound from the terminal?

I'm wondering if there's a command I can install to play an audio file from the terminal, or if I can do it with Python or a different code?  I just want to type a command, have it play a sound until the sound is finished, then return to the prompt.  I don't want a GUI.


Scroll summary page to bottom, if there are no issues with the question

When I am done with a longer question, I have to scroll down "Ask question" page to the bottom, to hit "Review your question" button. When this is done, and my question is reviewed, I have to scroll down again, sometimes really long distance (if my question includes a lot of images) to the very bottom again to hit the "Publish" question. This is quite annoying. Can we have any resolution for that? I.e.:  move / copy "Post your question" button under "Step 2: Review your question" box, add functionality of auto-scrolling down the whole page to the "Post your question button" when there are no issues with the question ("Your question is ready to publish!" result) and only keep it to, if indeed there is something to be fixed, any other option or idea.  I know this is tiny and might be considered as my laziness, but I think this is still an UX issue.


Explainer badge - the 12 hours should be based on when the edit was made, not approved?

I've been finding that even when I edit a question, and then immediately write an answer, the time for edits to be approved can often exceed 12 hours. I'm thinking that's why these often don't count towards the Explainer badge. Another exacerbating factor is that my edit queue can get full and remain so for a couple of days until cleared by someone; this edit queue issue is mostly only with Stack Overflow, whereas the Explainer badge issue of exceeding 12 hours happens on various Stack Exchange sites as well.  Could the timing of the 12 hours be made with reference to when the edit was made, rather than (as it appears to be currently) with reference to when it is approved?


Can I have a flexible partial derivative macro?

I was thinking about writing a partial derivative macro that has a similar syntax to the . ()  The syntax could be like this:   \D{f}{x} expands to \frac{\partial f}{\partial x} \D{f}{x,y} expands to \frac{\partial^2 f}{\partial x\,\partial y} \D{f}{{x,2},y} expands to  \frac{\partial^3 f}{\partial x^2\,\partial y} et cetera for any number of derivatives.   Bonus points for an optional argument so that for instance   \D[subscript]{f}{{x,2},y} expands to f_{xxy}   I looked at the  package but the syntax is a little tedious.  For instance, to get \frac{\partial^3 f}{\partial x^2\,\partial y} with that package I would need to do \md{f}{3}{x}{2}{y}{}.  And it doesn't generalize to three variables.  Before I dive in I thought I'd ask the hive and see what's been done.


When a name finishes in "s" can you say Jaume Casals's biography?

Is this sentence correct?  Here you can find Jaume Casals's biography.   I think the final " 's " is unnecessary, but I am not 100% sure. Could anyone help?  Thanks.


How to use "had" correctly in a past perfect paragraph?

Consider the following paragraph:  My account was suspended after I used what I believe was an expired confirmation code for changing my payment details. I had not received a confirmation email immediately after switching to Payoneer from PayPal on the website. When it arrived 2-3 hours later, I had clicked on the link in it and had entered the confirmation code but was told that the confirmation code was incorrect. I had tried a couple of times more thinking maybe I had done something wrong the first time around but the error message persisted. Immediately after that, an email had arrived saying that my account was going to be suspended for security reasons.  The first sentence of the paragraph describes what happened to my account (it was suspended), and the rest of the paragraph details what led to the suspension. So, if the first sentence is in simple past tense, then the rest of the paragraph has to be in past perfect tense. Have I used "had" and "was" correctly here? If not, could you please point out the mistakes?


In Powershell Retrieving Printed Message From SSMS

Our DBA team doesn't verify the backups using the below TSQL (which can easily be done post-backup and takes almost no time, so I don't get why not):  RESTORE VERIFYONLY FROM DISK = 'D:\Backups\LOCATION'   They've had issues in the past, so even though we'd think they'd learn from it, they haven't.  I created a Powershell script to do this because we have about 100+ servers and I just want to run this script against all the backups just to ensure they're valid.  The below script runs correctly (in that it doesn't break or throw errors), I am curious if there's a way to get the printed message back in Powershell that we would normally get in SSMS where it states The backup set on file 1 is valid as verification.  $SqlCon = New-Object System.Data.SqlClient.SqlConnection $SqlCon.ConnectionString = "SERVER=SERV\INST;Integrated Security=true;DATABASE=master"  $baks = Get-ChildItem "D:\Backups\" -Filter *.BAK  foreach ($bak in $baks) {     $SqlCon.Open()     $cd = New-Object System.Data.SqlClient.SqlCommand     $cd.Connection = $SqlCon      $cd.CommandText = "RESTORE VERIFYONLY FROM DISK = @f"     $cd.Parameters.Add("@f", $bak.FullName)     $cd.ExecuteNonQuery()     $SqlCon.Close() }


When I try to run an example application it says I am missing  a file that is found in OpenGL. I found information online and tried to install OpenGL with the following command:  sudo apt-get install libglu1-mesa-dev freeglut3-dev mesa-common-dev  Reading package lists... Done Building dependency tree        Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies.  freeglut3-dev : Depends: libgl1-mesa-dev but it is not going to be installed or                           libgl-dev                  Depends: libxt-dev but it is not going to be installed                  Depends: libxext-dev but it is not going to be installed  libglu1-mesa-dev : Depends: libglu1-mesa (= 8.0.2-0ubuntu3) but 8.0.4-0ubuntu0.4 is to be installed                     Depends: libgl1-mesa-dev but it is not going to be installed or                              libgl-dev  mesa-common-dev : Depends: libx11-dev but it is not going to be installed                    Depends: libdrm-dev but it is not going to be installed E: Unable to correct problems, you have held broken packages.   How do I fix this ?


Unity-like Dashboard for Gnome fallback?

Is there any way I can run the Unity dashboard (or something similar, like Bolt for Gnome 3) in Gnome Fallback?


What's the use of assigning foreign keys on MySQL

Aside from indexing the value of the foreign key, what is/are the advantage of assigning foreign keys to databases? I've seen a lot of databases that does not assign foreign keys, but is relational by their schema. One example is the database of the wiki (mediawiki). I've studied their schema and although their tables are interconnected using the primary key of one table, they aren't assigning any foreign keys.


What is meant by the term "meta-parameter"? Can a definition, informal and/or formal, be provided?  For example, in reduced-rank regression, the rank ($r$) can be referred to as a meta-parameter of the method. For instance, see these , which I quote below.     The optimal choice of the rank $r$ will usually be unknown, and is   considered as a meta-parameter of the method.   Reference: Reduced-rank regression, by Magne Aldrin (2002) in Encyclopaedia of Environmetrics.


It seems, that the problem happens not the first time ()  Just now the state of uml tag on my profile is about 7 days old.   A year ago it was told: "We changed the way we were calling the job that was timing out, so this issue shouldn't recur. " - I am afraid, something broke the process again.  And the problem exists for about a month already: look at the comment below the .


How to cut shape on top of another one in illustrator?

I'm working on Adobe Illustrator CS6 and I've a question about how to cut an area from a shape using another shape. To clarify the point, I've the first image below.  What I want to do, is to 'cut' the circle shape from the rectangle, so that the rectangle will have a centre transparent hole; image (2)   And of course, if I change the background, it'll look like image (3)     Thanks in advance


How to quote a book that has a quote in the text that I'm quoting?

I'm trying to quote this in my paper:     despite the universal desire to return to "normal," things changed   How would I quote this in MLA? Would I substitute the double quotations for single, or use double quotes for everything?  Any help would be greatly appreciated.


The usage of Who in 'Who can Curly see?'

'Who can Curly see?' is the title of a book for kids. Curly is the name of a caterpillar. The book is to show that Curly saw several kinds of insects. When I read it I think the who should be whom instead.  I am not an English native speaker and I am not sure the use of who is correct or not in this book's title.  So could you help to clarify this?  Thanks.


I have been moving toward Ubuntu from a long time Windows development background. The one program I cannot seem to do without is a graphic editor. I have seen recommendations for programs, but they turn out to be directed at children or tailored to working with personal photographs.  I am looking for something more for programming tasks like analysing colors, resizing, creating web graphics, etc. I have used Photoshop in the past and more recently have mostly used Paint.net for Windows.  Is there a program for Ubuntu that covers this area?


There are five copies of a book each 20mm thick. When tilted, they fit snugly inside a cubic box with a gap of 16mm at the bottom left as shown.   I struggled with this in a recent practice paper, any help appreciated.


Where could I find/download/install Ubuntu application software?

I have installed Ubuntu 16.04.2 LTS, and found that there are fewer applications in Software Center, for example, I could not find Evolution for email.  Is there any other way that I could obtain Ubuntu application other than using the Software Center, and download / install them?


c# set class property from another class

I am using Visual Studio and c#. I have a form that contains a Developer Express data-aware treelist called treelist1, which has a datasource property.  I created a method to set the datasource property of the treelist: public partial class UserControl1 : UserControl    {     public UserControl1()             {         InitializeComponent();     }             public void SetTreelist1DataSource(System.Data.DataTable dataTable)     {         treeList1.DataSource = dataTable;     } } }  I am trying to set the dataTable property from another class: class DataAccess {     public static void LoadDataSource()     {         string constring = "Default";         using (SqlConnection cstr = new SqlConnection(constring))         {             using (SqlCommand cmd = new SqlCommand("SELECT * FROM Customers", cstr))             {                 cmd.CommandType = CommandType.Text;                 using (SqlDataAdapter sda = new SqlDataAdapter(cmd))                 {                     using (DataTable dt = new DataTable())                     {                         sda.Fill(dt);                         UserControl1.SetTreelist1DataSource(dt);                                                 }                 }             }          }     }  } }  The line UserControl1.SetTreelist1DataSource(dt);  gets the compiler error, "An object reference is required for the nonstatic method, data field or property usercontrol1.settreelist1datasource(datatable)". Any constructive help would be greatly appreciated. Paul


Ubuntu is not detecting my android device

I am new to android. I have just downloaded and installed android sdk. Now when I run the application from  eclipse, my device is not getting detected. I have googled and was brought up with this as my solution, but that also didn't worked.  Here's the 51-android.rules  SUBSYSTEMS=="usb", ATTR{idProduct}=="0bb4",  ATTR{idProduct}=="0c03", MODE="0666", GROUP="plugindev", OWNER="<username>"   After that I rebooted my laptop, and ran this command:  username@laptopname:~/Android/adt-bundle/sdk/platform-tools$ adb devices   The output i get is:  * daemon not running. starting it now on port 5037 * * daemon started successfully * List of devices attached  ????????????    no permissions   EDIT  crazydeveloper@crazydeveloper:~$ lsusb Bus 002 Device 004: ID 0bb4:0c03 HTC (High Tech Computer Corp.)  Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 003: ID 04f2:b337 Chicony Electronics Co., Ltd  Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub crazydeveloper@crazydeveloper:~$ ls -l /dev/bus/usb/004/ ls: cannot access /dev/bus/usb/004/: No such file or directory crazydeveloper@crazydeveloper:~$    Edit: 2  After the answer submitted here's the output that i got:  crazydeveloper@crazydeveloper:~$ ls -l /dev/bus/usb/002 total 0 crw-rw-r--  1 root root    189, 128 May  7 09:45 001 crw-rw-r--+ 1 root root    189, 129 May  7 09:45 002 crw-rw-rw-  1 root plugdev 189, 130 May  7 09:48 003   I am using Micromax Canvas 2.2 A114 - Android Version 4.2.2  Please help me. Thanks.


How I can to create a list with enumerate 2 by 2? e.g.  1. ... 3. ... 5. ... ...   In general, How I can create a step-by-step list? Is it possible?


rMBP kernel_task spikes when connecting more than one external monitor

When connecting a second external monitor kernel_task spikes to 600%+. This makes the computer unusable.  Before Yosemite, this worked fine with 3 monitors.  Here are the specifics:    When I connect one monitor to either DP or HDMI things work fine. When I connect a second monitor with either DP or HDMI kernel_task spikes. When I disconnect either the DP or HDMI sometimes the kernel_task rapidly returns to normal levels. When I disconnect all monitors the kernel_task rapid returns to normal levels. (In Activity Monitor goto View > Update Frequency > Very Often and as soon as you disconnect the monitors, you will get lots of rapid updates to the UI). Occasionally when plugging in two monitors it works (DP or HDMI) but the 3rd causes an immediate spike. After this happens, all monitors must be removed for it to return to normal. Sometimes removing all but one will fix it. Sometimes when I plug all 3 in it takes 3 mins+ for it to occur.   What I have tried:   Resetting NVRAM. Resetting SMC. Attempting the above scenario with power adapter plugged in and running on battery. Disabling "Automatic Graphics Switching" in Energy Saver. Using integrated graphics by using sudo pmset -c gpuswitch 0   NOTE: When trying some of these things sometimes it takes 1min to happen.  System config:  I am running a MacBook Pro Retina 2.7Ghz i7 (Macbook10,1 / Mid 2012) running Yosemite 10.10.1.  I have 3 external monitors (Dell 2415H) with 2 connected by Display Port and 1 with the HDMI.    I think the issue has to do with power management. Whenever my CPU hits 58 degrees it seems to occur. I just left my 3 monitors plugged in for 5+ mins and it didn't happen. But when I started searching using Chrome it immediately happened.  Looks like a good fix here:


In an introductory stats book by Nicole Radziwell "Statistics the easy way with R" , an assumption used  for nearly every statistical test (e.g.t-tets, anova, etc) is that the sample size should not be more than 10% of the population size (where the population size in known).   I havent seen it mentioned in other introductory stats books. My question is: how important is theis assumotion and what is the reason for it?  The author didn't say where this comes from (at least as far as I could see). A bit of googling suggests that it refers to making a simple random sample without replacement, if the sample size is above 10% then the observations wont be (approximately) independent, and indepedence of observations is an assumption stated in most textbooks.   In the case where you have a small population (e.g. <50), should you give up on this assumption because it results in sample sizes too small to get decent estimates of variability and to check other assumptions such as normality.    Thank you for any insights.


Javascript is not executed for added html

For a project I'm working on I'm adding records to a list. But a button in the added content does not execute the javascript it is supposed to execute.   I've made a scribble out of it - as simple as I could make it - to demonstrate.  The button "some content to click" fires of an alert like I expect. The button 'some other content to click' does not.  I suspect this has to do with the html not being there on load... but I'm clueless on how to solve this.  Anyway... if you guys are willing to help... here is the code:  <!DOCTYPE html>       <meta http-equiv="content-type" content="text/html; charset=UTF-8">     <title>scribble</title>
         <button class='clickme'>add record</button>

                 <button class='record_button'>some content to click</button>


I want to prove that every power series is continuous but I am stuck at one point.  Let $\sum\limits_{n=0}^\infty a_n(x-x_0)^n$ a power series with a radius of convergence $r>0$ and let $D:=\{x\in\mathbb R:|x-x_0|<r\}$. Then $S(x)=\sum\limits_{n=0}^\infty a_n(x-x_0)^n$ is continuous on $D$.    Proof: Let $x\in D$ and $r_0\in\mathbb R^+$ such that $|x-y_0|<r_0<r$ and for any positive integer $N$ let $S_N(y)=\sum\limits_{n=0}^{N-1} a_n(y-x_0)^n$ and $\phi_N(y)=\sum\limits_{n=N}^\infty a_n(y-x_0)^n$.     Since the power series converges uniformly on the closed disk $|y-x_0|\leq r_0$, we may choose a positive integer $N_\varepsilon$ such that $|\phi_{N_\varepsilon}|<\frac\varepsilon3$ for all $|y-x_0|\leq r_0$.   Since $S_{N_\varepsilon}$ is polynomial we can choose a $\bar\delta>0$ such that $|S_{N_\varepsilon}(y)-S_{N_\varepsilon}(x)|<\frac\varepsilon3$. So we get $|S(y)-S(x)|<\frac\varepsilon3+\frac\varepsilon3+\frac\varepsilon3=\varepsilon$ for $|y-x|<\delta$    Why is in the violet term $|\phi_{N_\varepsilon}|<\frac\varepsilon3$ correct? Don't I have two terms in the absolute value? Thanks for helping!


What is the radius of convergence of $\sum z^{n!}$?

How to find the radius of convergence of $\sum z^{n!}$?   I'm used to applying the ratio test to power series of the form $\sum a_{n}z^{n}$, but for a different power of $z$, I am a bit stumped. What about $\sum z^{2n+a}$ for another example? Where $a\in \mathbb{R}$.


compare two strings of an excel having two words and write accordingly

i want to compare two colums in and excel and write the result in the 3rd column.  input file is like this below   output file should be like this    This is wat i have done till now   import java.util.List; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException;    import jxl.Cell; import jxl.Sheet; import jxl.Workbook; import org.openqa.selenium.By; import org.openqa.selenium.WebDriver; import org.openqa.selenium.WebElement; import org.openqa.selenium.firefox.FirefoxDriver; import org.testng.annotations.BeforeClass;  import java.io.FileInputStream;  import jxl.Cell; import jxl.Sheet; import jxl.Workbook; import jxl.format.Colour; import jxl.format.Pattern; import jxl.read.biff.BiffException; import jxl.write.Label; import jxl.write.WritableCellFormat; import jxl.write.WritableFont; import jxl.write.WritableSheet; import jxl.write.WritableWorkbook; import jxl.write.WriteException; import jxl.write.biff.RowsExceededException;  public class Test {      /**      * @param args      */ //variable declarations      String element;     static String storedElement[][]=null;     static String Element[][]=null;       public static void main(String[] args) throws BiffException, IOException, RowsExceededException, WriteException {         // TODO Auto-generated method stub          FileInputStream fs=new FileInputStream("file location(.xls)");           Workbook wb=Workbook.getWorkbook(fs);         Sheet sh=wb.getSheet(0);          Workbook workbook = Workbook.getWorkbook(new File("file location(.xls)"));         WritableWorkbook ww= Workbook.createWorkbook(new File("file location(.xls)RENAME THE FILE here "), workbook);         WritableSheet ws=ww.getSheet(0);          Label label;          //retrieving values from excel and storing in array         storedElement = new String[sh.getColumns()][sh.getRows()];         Element = new String[sh.getColumns()][sh.getRows()];         //for (int j = 0; j <sh.getColumns(); j++)          //{          int j=0; //column #0         int q=1; //column #1         //StringBuilder sb = new StringBuilder();         for (int i = 2; i < sh.getRows(); i++) //loop to run all rows          {             Cell cell = sh.getCell(j, i);             Cell cell1=sh.getCell(q,i);              storedElement[j][i] = cell.getContents();             Element[q][i]=cell1.getContents();             String elem =  storedElement[j][i];             System.out.println(elem);             String elem1= Element[q][i];             System.out.println(elem1);             String[] ob1=elem1.split("\n");             System.out.println(ob1[i]);             String[] ob = elem.split("\n");             System.out.println(ob[i]);           //for(int k=0;k<ob.length;k++){             int k=0;             while (k<ob.length){             if (ob[k]==ob1[k]){                     System.out.println(ob[k]);                     System.out.println(ob1[k]);                     label=new Label(2,i,"Valid");                 }                 else {                     System.out.println(ob[k]);                     System.out.println(ob1[k]);                     label=new Label(2,i,"InValid");                  }             k++;             //add new line ??                  ws.addCell(label);                 ww.write();                 ww.close();                 workbook.close();                   }         }      } }   i want to compare two columns in and excel and write the result in the 3rd column. here the cell contains two words where i need to write status for two words please help me in doing it


why doesn't filter() accept my variable which is a function?

so isDog is clearly a function, I tested it with typeof but when I run the program I get a 'TypeError: undefined is not a function at Array.filter.' Am I thinking about this wrong? btw, I do know var dogs = animals.filter( (animal) => animal.species === 'dog'); works but confused as to why I cannot assign that function to a var and call it.  var animals = [   { name: 'Fluffykins', species: 'rabbit' },   { name: 'Caro',       species: 'dog' },   { name: 'Hamilton',   species: 'dog' },   { name: 'Harold',     species: 'fish' },   { name: 'Ursula',     species: 'cat' },   { name: 'Jimmy',      species: 'fish' } ]  var dogs = animals.filter(isDog);  var isDog = function(animal) {   return animal.species === 'dog'; }


Let $A$ and $B$ be two matrices in $M_{n,p}(R)$. Show that $A^{T}A = B^{T}B \iff \exists P \in On(R)$ such that $B = PA$.

let A and B two matrices in $Mn,p(R)$ show that $A^T$$A$=$B^T$$B$ if and only if there exist $P$ belong to $On(R)$  s.t  $B$=$PA$.


Why can't a particle that carries magnetic charge exist?

Electron is the source of electric field and changing electric field produce magnetic force, what about particle that can do vice versa? My concern is how come universe favors particles that carry electric charge but not magnetic charge? What prevailing theory can explain this discrepancies?


Is there a way to distribute Wi-Fi load across multiple adapters?

I have 4 wireless USB adapters, all of which are poorly supported by Linux. The connection is unstable, the USB dongles overheat at regular intervals, and the Wi-Fi adapters themselves often become chokepoints, even with our 6 Mbit DSL. (Before you ask: yes, I've updated the drivers, and, yes, they all work like a charm on Windows.)  What I have to do currently is just use one until it smells funny and can't connect, then unplug it, blow on it, put it in the fridge, and replace it with the next. This can become quite a tedious process during heavy browsing - my computer is on the other side of the house.  What I'm wondering is if there's a way to distribute the load across all 4 adapters - so each one never has to process more than ~1.5 Mbps.


Having done something vs doing something

Do these two sentences mean the same thing? If not, please elaborate. If there are grammar mistakes, please help me correct them.    Growing up in California, I experienced life that was different than most people in Mexico. Having grown up in California, I experienced life different than most people in Mexico.


I was wondering if anyone knows the origins of how Schrodinger arrived to his equation? And can it be derived from Newtonian mechanics? How did Schrodinger form the equation out of his MIND?  I also I was asking because I was playing around with Newtonian mechanics, I believe I derived the Schrodinger equation...


Is there a way to start a section from a different number than 1 (such as 0 or 11)

In my textbook, vector-valued functions is the twelfth chapter, and I would like to be able to make a new document starting from chapter 12. Is there a way I can start the sections in a new document from 12 instead of 1?


Disable mounting Internal Macintosh HD at boot

My iMac (mid-2010 model, Snow Leopard) has a problem with S.M.A.R.T status: Failing and it has become read-only. Because I didn't want to waste money on the repair, I bought an external HD, so the internal HD is now unnecessary. How can I disable mounting the internal Macintosh HD at boot?


I manage the IT systems for a small business with around 7 members of staff. They currently have a Mac running Server.app with Open Directory and the Home Folders are hosted on that Mac.  They have Mac Mini's that are joined to the network account server. Although this is working well, there has been a couple of instances where the Open Directory has become corrupt and it also seems the future of Open Directory is uncertain and Apple may not be supporting this set up for much longer.  My question is whether this is still the best set up and/or if anyone can suggest a better way of achieving this?  Thanks in advance,  Andy


WKT for EPSG:4326 with LON 0 to +360 instead of -180 to +180

I have GRIB2 files that seem to be in a projection similar to EPSG: 4326, except that instead of longitude between -180 and +180 it is between 0 and 360.   My intention is to get these files into geoserver and allow the data to be queried and reprojected at will through the WMS. I can get these files into geoserver with the GRIB extension, but I get a null pointer error when I attempt to reproject to mercator. I assume that this error occurs because data lies outside the -180 to +180 longitude bound.  I had attempted to just reproject the GRIB files with gdal_translate, using the PROJ4 +lon_wrap=180option, but that operation takes forever and produces a far larger output file for some reason.     From what I understand, I can fix this situation by creating a custom projection in user_projections/epsg.propertiesthat describes the CRS of these GRIB files. A custom projection for geoserver must be in the WKT format.  TL;DR: How do I write a WKT that describes a lat/lon coordinate system similar to EPSG: 4326 but with longitude ranging from 0 to +360 instead of -180 to +180?  Here is the gdalinfo for one of these GRIB files. The file depicts the continental United States:  Size is 2847, 1517 Coordinate System is: GEOGCS["Coordinate System imported from GRIB file",     DATUM["unknown",         SPHEROID["Sphere",6371229,0]],     PRIMEM["Greenwich",0],     UNIT["degree",0.0174532925199433]] Origin = (229.982699929725896,55.001944129287601) Pixel Size = (0.024600140548138,-0.023088258575198) Corner Coordinates: Upper Left  (     229.983,      55.002) (229d58'57.72"E, 55d 0' 7.00"N) Lower Left  (     229.983,      19.977) (229d58'57.72"E, 19d58'37.40"N) Upper Right (     300.019,      55.002) (300d 1' 9.48"E, 55d 0' 7.00"N) Lower Right (     300.019,      19.977) (300d 1' 9.48"E, 19d58'37.40"N) Center      (     265.001,      37.490) (265d 0' 3.60"E, 37d29'22.20"N)   gdalsrsinfo:  PROJ.4 : '+proj=longlat +a=6371229 +b=6371229 +no_defs '  OGC WKT : GEOGCS["Coordinate System imported from GRIB file",     DATUM["unknown",         SPHEROID["Sphere",6371229,0]],     PRIMEM["Greenwich",0],     UNIT["degree",0.0174532925199433]]   Screenshot from QGIS:   Edit: This is not a duplicate. I have seen the answer from the referenced question, and it is not satisfactory. The operation takes too long to complete and produces a file that is entirely too large.  Edit #2: Added a link to the GRIB file:


Can I post redesigns of album covers in my portfolio online?

Former student in graphic design, I am currently working on personal projects to widen my portfolio. I love to design album covers. I never had clients for that, so I have been re-designing real albums from real artists. I was wondering if I can post these personal projects on my website knowing that these albums actually exist and that my design is not the official one (regarding the artist who originally designed the cover). Would it be even legal?


Deriving the KL divergence loss for VAEs

In a VAE, the encoder learns to output two vectors:  $$\mathbf{\mu} \in\ \mathbb{R}^{z}$$ $$\mathbf{\sigma} \in\ \mathbb{R}^{z}$$  which are the mean and variances for the latent vector $\mathbf{z}$, the latent vector $\mathbf{z}$ is then calculated by:  $$\mathbf{z} = \mu + \sigma \epsilon$$  where: $\epsilon = N(0, \mathbf{I}_{z \times z})$  The KL divergence loss for a VAE for a single sample is defined as (referenced from  and ):  $$\frac{1}{2} \left[ \left(\sum_{i=1}^{z}\mu_{i}^{2} + \sum_{i=1}^{z}\sigma_{i}^{2} \right) - \sum_{i=1}^{z} \left(log(\sigma_{i}^{2}) + 1 \right) \right]$$  Though, I'm not sure how they got their results, would anyone care to explain or point me to the right resources?


Calculation surface of building external walls from shapefile

I have two datasets ():   1) A shapefile of buildings containing the height of each building.  2) A parcel shapefile. Several buildings are assigned to a single parcel.   I am interested in calculating the sum of the surface of external walls of buildings (m2) in each parcel. In other words, I want to know how many square meters (m2) of external walls I have in each parcel.  However, it is important for me to exclude those walls which are in common in between buildings. For instance, if two buildings with the heights of 10 m and 6 m are attached from one side, the goal would be to include 4 m of the 10 m external wall and exclude the 6 m which both walls are attached with each other. I hope I was successful in describing the question.


Why does Snape suggest Malfoy use the Serpensortia spell?

In Chamber of Secrets, in the first Duelling Club class, Snape suggests Malfoy use the Serpensortia spell against Harry. This of course reveals that Harry is a Parselmouth, but how could Snape anticipate this? Was there any reason for Snape to suspect Harry is a Parselmouth? Or was it just a way to laugh at how Harry would get frightened?


What is someone called who places in the top 3 of a competition?

We held a competition, and I am writing a Congratulations email to those who placed 1st, 2nd, and 3rd, but I don't know what to call them. Are they place-holders? There wasn't an award ceremony, so I don't feel that medalists works.


Complex Integration of $\int_0^\infty e^{-ax}\cos(bx)\,dx$

Out of Stein's book, we're asked to show find a formula for $$\int_0^\infty e^{-ax}\cos(bx)\,dx,\quad a>0.$$While this is very doable via integration by parts, I'm asked to use contour integration, where we're suggested to integrate over a sector with angle $\omega$ such that $\cos(\omega)=a/\sqrt{a^2+b^2}.$  I've attempted this multiple times, and I keep having trouble with some integrals. I've set the contour up so that on the first segment, it's on the real axis, so we have the integral $$\int_0^R e^{-az}\cos(bz)\,dz.$$ Then I parameterize the arc as $z(\theta)=Re^{i\theta}$ for $0\leq\theta\leq \omega$, so the second integral becomes $$\int_0^\omega e^{-a(Re^{i\theta})}\cos(b(Re^{i\theta}))\left(iRe^{i\theta}\right)\,d\theta.$$The final segment I parameterized as $z(t)=Re^{i\omega}(1-t)$ and set up the final integral as $$\int_0^1e^{-a(Re^{i\omega}(1-t))}\cos\big(b(Re^{i\omega}(1-t))\big)(-Re^{i\omega})\,dt.$$I've tried finding some way to bound one of the last two integrals so that I can show one of them goes to $0$ as $R\to\infty$, but I've not had any luck. Will someone make a suggestion if my approach and parameterizations are correct? Thanks!  Update: My thoughts are really that the integral which goes to zero is the arc. I keep working it down in the following way; we know that it is  \begin{align} &\leq R\int_0^\omega\left|e^{-aR(\cos\theta+i\sin\theta)}\cdot\left(\frac{e^{ibRe^{i\theta}}+e^{-ibRe^{i\theta}}}{2}\right)\right|\,d\theta\\ &\leq\frac{R}{2}\int_0^\omega\left|e^{-aR\cos\theta}\cdot\left(e^{ibR(\cos\theta+i\sin\theta)}+e^{-bR(\cos\theta+i\sin\theta)}\right)\right|\,d\theta\\ &\leq\frac{R}{2}\int_0^\omega\left|e^{-aR\cos\theta-bR\sin\theta}\right|+\left|e^{-aR\cos\theta+bR\sin\theta}\right|\,d\theta. \end{align} At this point, it is easy to show that the first term tends to zero, since $(-aR\cos\theta)<0$ and $bR\sin\theta>0$ (since $b$ and $\sin\theta$ have the same sign). The second term, however is what causes me trouble. I just finished working it out again, and I get that it only goes to zero if $a^2>b^2$, which isn't necessary in the general formula when achieved by integration by parts. I am really at a loss...  Added Solution: See the solution I've posted and please leave comments on your thoughts about it. Thanks!


How to decide which collection should be used from List Set?

I want to know when to use Set and List.On which basis it should be decided.For example, when we are dealing with order application, at that what should I use? List any = new ArrayList<>(); or Set any = new HashSet(); or LinkedList.


Representations of Direct Sum of Lie Algebras

I'm trying to prove the following. Let $\frak{g}$ and $\frak{h}$ be (semisimple) Lie algebras. Then every representation $d$ of $\frak{g}\oplus\frak{h}$ is the tensor product of representations $d^1$ on $\frak{g}$ and $d^2$ on $\frak{h}$; that is $d=d^1\otimes d^2$.  $d^1$ and $d^2$ are cannot be defined by restriction (see comment below). I don't know how to define them so that their tensor product must give back $d$. In particular how do I know that the vector space $V$ of $d$ decomposes appropriately for this to work?  Any hints would be much appreciated!


Password dialog appears when SSH private key permissions are set to 0600

I installed my SSH private key in ~/.ssh/id_rsa and set its permissions to 0600.  When I connect to an SSH server which uses my private key in Terminal.app via ssh, a dialog pops up and asks me to enter my password to access the id_rsa file:    I see the same dialog when I connect to an FTP server with the Interarchy GUI client.  Update: I see this dialog every time I connect regardless of whether I check "Remember password in my keychain".  It appears two more times if the OK button is clicked regardless of what is entered in the password field.  When I relax these permissions to, say, 0640, I no longer see a dialog asking me for my password but ssh aborts with the following error:  @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @         WARNING: UNPROTECTED PRIVATE KEY FILE!          @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ Permissions 0640 for '/Users/myusername/.ssh/id_rsa' are too open. It is recommended that your private key files are NOT accessible by others. This private key will be ignored. bad permissions: ignore key: /Users/myusername/.ssh/id_rsa  I find the password dialog extremely annoying and I am sure there must be some way to avoid having to dismiss this dialog SSH needs to access the id_rsa file.  Note: I am running Mac OS X 10.6.8.


Translating multidimensional hash in Perl to Python dict

I have a program in Perl that I want to translate into Python. Right now the focus is on rote translation, then I will go through and make it more Pythonic (there are a lot of files and a couple people working on it so I don't want to mess up the logic flow by changing the code too much).  The Perl code creates a hash InputData that it fills with data from an input file. At first it was 1-dimensional, so I just used a dictionary. Then the code added a second dimension, and after looking at  I used defaultdict(dict). Now my Perl code has added a third dimension and looking forward in the code there is a fourth dimension used as well.  I have been testing dicts in Jupyter Notebook, and I get this KeyError when I try to add a third dimension.  my_dict = defaultdict(dict) my_dict['Status'] = 'free' my_dict['Results']['Test1'] = 1 my_dict['Variables']['Coords']['X'] = 2  --------------------------------------------------------------------------- KeyError                                  Traceback (most recent call last) <ipython-input-19-dbbf5ada990b> in <module>       2 my_dict['Status'] = 'free'       3 my_dict['Results']['Test1'] = 1 ----> 4 my_dict['Variables']['Coords']['X'] = 2  KeyError: 'Coords'   Is there some other way to create a multidimensional Python dict? Is this ridiculous? What other data type could I use instead?  Thanks for any help!


C sizeof((x)) not working when I pass x as a pointer

When I use the size of function in the main function it works correctly. However when i use it in the reverse function it only returns 8. Any ideas why or did i incorrectly use it.(This is the beginning of a assignment where I must reverse a string passed to the reverse function. I may only pass the string and nothing else and cannot use the string.h library. If there is another way to accomplish this please let me know. I was planning on using the sizeof function to get the size then looping through the array and use a temp variable to reverse it as I loop.)       #include <stdio.h> char reverse(char *x); int main(int argc, char* argv[]) { char word[] = "Apple pies"; printf("%s\n", word); reverse(word); printf("%s\n", word); printf("%s\n", reverse(word)); printf("%s\n", word); return 0; } char reverse(char *x) {     char crud;     int lc =0;     size_t length = 0;      char *tmp = x;      while (*tmp++)      ++length;     while (length > lc)     {         crud = x[length];         x[length] = x[lc];         x[lc] =crud;         length--;         lc++;      } }


I have two lists I produce using the following commands:   find . -type f -name config.php -exec ls {} \;  find . -type f -name config.php -exec grep --files-with-matches some_string {} \; | sort    How could I pipe the lists into com -23 so I can see those entries from list1 that aren't contained in list2?


I have a few questions regarding Named Credentials. I need to perform a SOAP based call out to an external system from Sales Force. I used the wsdl2apex function to generate the class for the call out. When I started integrating this class into my process I got to thinking about securely storing the username and password for the call out, which led me to discover Named Credentials. Question is, can Named Credentials be used in the auto-generated apex class? If so, could you please provide an example?  Thanks in advance


What do r (Pearson correlation coefficient) and R^2 stand for?

As far as I understood, R squared explains how much the variation in Y is explained by its linear association with X. And it's used as an indicator for goodness of fit of a linear model.  Then when should I use r (Pearson coefficient)? How is it useful?


Confusion about how Java deals with aggregation and referencing

I am confused about how Java deals with aggregation within objects, and in particular referencing of objects. It seems like objects will keep a reference to an aggregated object when it is passed as a parameter, rather than copying it like I've been lead to believe.  Say I have a basic class called Foo which contains a string attribute, print function, and setter for the text attribute.   public class Foo {      private String text;      public Foo(String text) {         this.text = text;     }      public void print() {         System.out.println(text);     }      public void setText(String text) {         this.text = text;     }  }   And a class called Bar which contains an attribute of type Foo, and a method called print which calls foos print method.  public class Bar {      private Foo foo;      public Bar(Foo foo) {         this.foo = foo;     }      public void print() {         this.foo.print();     }  }   If I define an instance of Foo, pass it into a new instance of Bar, and then call bars print method it will print "hello" as I expected. However if I then set the text of the original instance of foo to "Edited" using its setter method, bars print method will also print "Edited".  public static void main(String[] args){      Foo foo = new Foo("Hello");     Bar bar = new Bar(foo);     bar.print();     foo.setText("Edited");     bar.print();  }     The Bar object appears to be keeping a reference to the Foo object even though I passed it as a parameter. I'm sure I am missing something trivial here, and I just wanted someone to explain this clearly.


mails are going to spam folder when i change from mail

this mail going to spam. when i change email->from then it goes to inbox.    how to send email to inbox with this email id    $this->email>from("sweco@suzlon.com");           $this->email->from("sweco@suzlon.com");         $this->email->to("marmik0011@gmail.com");          $this->email->subject($subject);                $this->email->message($body);         $this->email->set_mailtype('html');          $this->email->send();   this mail going to inbox.               $this->email->from("info@gmail.com");         $this->email->to("marmik0011@gmail.com");          $this->email->subject($subject);                $this->email->message($body);         $this->email->set_mailtype('html');          $this->email->send();


Can't flag or close questions on all sites

Whenever I try to flag or close a question here, when clicking the submit button the button gets disabled, three dots animating and nothing really happens.  JS console show a single error:  Flagging:     Uncaught TypeError: Cannot read property 'flagSubmitting' of undefined    Closing:     Uncaught TypeError: Cannot read property 'closeSubmitting' of undefined   Please fix, programming questions and spam are beginning to pile up. :(  Update: appears to work fine from within the review system, but otherwise it's the same on Stack Overflow as well


Is there a word to describe when someone has super-sensitive hearing?

What word or phrase could be used to accurately describe when someone has excellent or super-sensitive hearing far beyond that of most people, where they might have, for example:   the ability to hear in detail a much further distance, for example an approaching aircraft 10 seconds before anyone else can hear it; increased ability to differentiate and split sounds to identify and process them in parallel, for example listen to 5 or more different conversations at once in a noise room and be able to relay what was said later; the ability to hear a frequency and quickly identify it approximately; frustration that they always tune-in to constant or repeating background noises/sounds such as generated by electrical appliances, transformers, vibrations, ticking clocks, dripping taps, several rooms away, and even if so quiet no-one else can hear them or notice them except up close.


How do I mentor a GM to-be without overwhelming him?

In our group we have several new players. They have played about 5-10 sessions so far, and one of them has shown interest in GMing and has begun the process of becoming a GM. However, the player has also shown that he has trouble with "paperwork" (Has a hard time keeping track of his spells, finds it difficult to look things up from a book or the internet, etc.).  The player himself does not really know where to start, and I want to help him with that. I do not want to keep the player from trying to GM something, but I am afraid that I will quickly give too much advice, or too much "homework", in the sense of "Read this article!", "Read this book!" and "Look at these useful websites!" I do not want to overwhelm the player, and make GMing seem scary.  How do I mentor a GM to-be, without overwhelming him?  So far, I have only advised the player to read the Dungeon Master's Guide. He is aware of the huge amount of supplements available to him, but hasn't made a character with content outside of core, which leads me to believe he is not familiar with many books. How do I introduce him into the extra books without overwhelming him?  Furthermore, the player doesn't seem to realise how much work should be put into preparations. Is there some way I can ease it up for him at first, or should I just throw him into the deep?  I do NOT need advice on how to encourage my player to become a DM. He already wants to become a DM, the process has already started. I am asking how I should guide him, without changing this.  I do NOT need advice for my player; I will give this advice myself. I want advice on how I should guide him.  I want answers that can be backed by personal experiences or blogs/articles.


Why didn't Voldemort hide his Horcruxes in impossible-to-reach places?

Nobody knew about his Horcruxes (even Slughorn wasn't 100% sure). But still, there was a small probability that someone could discover his secret. So, he hid his Horcruxes very well. But, there was always a way to get to those Horcruxes.  Why didn't he hide his Horcruxes in a place which was out reach of anyone? Some examples: His own stomach, Center of Sun/Earth/Black Hole etc. He could also had simply made Voyager-1 a Horcrux..


Rather than using mount | grep, I'd like to use mount -l -t bind, but that doesn't work, and -t none shows all mounts.


What is the difference between these sentences?  You may regret it. You might regret it.


Prove that there exists a smooth map $g\colon R\to R$ such that $f(\cos(t),\sin(t))=(\cos(g(t)),\sin(g(t)))$ and satisfying $g(2π)=g(0)+2\pi q$.

Let $f\colon S^1\to S^1$ be any smooth map. Prove that there exists a smooth map $g\colon\mathbb{R}\to\mathbb{R}$ such that $f(\cos(t),\sin(t))=(\cos(g(t)),\sin(g(t)))$ and satisfying $g(2π)=g(0)+2\pi q$.  The book told me to show that $g(2\pi)=g(0)+2\pi q$, then extend $g(t+2\pi) =g(t)+2\pi q$.  But I don't understand what they mean. How can I get function $g$ from $f(\cos(t),\sin(t))=(\cos(g(t)),\sin(g(t)))$, and what is $g$?


Disclaimer:  I am not an artist.  I created a model in blender.  I switched my mode to "Texture Paint".  I painted the model.  When I export as an FBX or switch back to "Object Mode", my paint goes away.  I am opening my FBX View 3D, a native Windows 3D model viewer.  Why does this happen, and how can I prevent it from happening?


Command equivalent on restarting explorer.exe in Windows

Is there command in Ubuntu that is equivalent on restarting explorer.exe in Windows?