I am new to c# and I have a trouble: Error CS0120 An object reference is required for the nonstatic field, method, or property In russian it is little bit different: Error CS0120 For non-static field, method, or property is required link to an object.  When I'm closing one form, that downloads some staff and saves it to a .xml files, I should update a combobox on the another form (This form contains a list of recently downloaded files.)  But I have an error. How can I fix it?  The code:  private void Reviews_browser_Closing(object sender, System.ComponentModel.CancelEventArgs e)     {         // Determine if text has changed in the textbox by comparing to original text.          // Display a MsgBox asking the user to save changes or abort.         if (MessageBox.Show("Закрыть, сохранив загруженные БД?", "Внимание!",            MessageBoxButtons.YesNo) == DialogResult.Yes)         {             // Cancel the Closing event from closing the form.             e.Cancel = false;             // Call method to save file...         }         else         {             e.Cancel = true;             try             {                 string[] dirs = Directory.GetFiles(@Directory.GetCurrentDirectory(), "*.xml");                 foreach (string dir in dirs)                 {                     if (Path.GetFileName(dir) != "HtmlAgilityPack.xml" && Path.GetFileName(dir) != ".xml")                     {                         int len = Path.GetFileName(dir).Length;                         glavnaya.fayly_s_otzivami.Items.Add(Path.GetFileName(dir).Remove(len - 4, 4));                     }                 }             }             catch (Exception oshibocka)             {              }         }


Are $n^2+n+41$ primes when $0\leq n \leq 39$?

I wrote a program to check and found, when $0\leq n \leq 39$, $n^2+n+41$ are primes.  But now I wonder: does it have a simple method to prove when $0\leq n \leq 39$, $n^2+n+41$ are primes without check it one by one?  Update: A similar question


Subject in sentence with only object pronoun

Let us go   is a correct construction in the English language and definitely not:     Let we go   However, the question is: since us is an object-case pronoun, what is the subject of this sentence?


I know what "this" keyword serves for but do not udnerstand why VS uses it nearly always, like this.Invalidate. If the call is placed within the class and there is no problem with identifier, what is it good for?


What properties should I consider when purchasing a non professional camera for taking pictures of family

I would like to purchase a camera that takes great pictures of people. We are having a family reunion and I would like to take clear pictures of everything going on: from people eating, to dancing, to the inevitable family portrait. Important:   Image sharpness Clear color Fast response when shot is taken Good Low lighting pictures   What should I look for in a non-professional portable camera in order to get the family shots that I want that I will be proud to show my grand kids some day? Minimum specs  P.S.- if you would like to recommend a model that you are happy with I would love some suggestions, even more so If you can link me to examples that have been taken with that camera.


I am beginner in blender. I want to make grass. but I want to put all parts of grass on the soil . but I can not. how to do it?


start process from ssh and be able to close connection

I'm connecting to my RaspberryPi with Raspbian installed via ssh and my problem is, that I can't let the RasPi do things (installing software, make calculations) while my Computer is shut down, since the processes I launch via SSH are child processes of the SSH shell and are terminated when the connection ends. I know i can disconnect child processes from the shell, but I'm not sure which way to use and it i would like to be able to see as much of the output of the process as possible (maybe in a file?).  BTW: I'm using PuTTY from Windows 7 :(


Testing for equality in two objects with nested arrays in javascript

I have two objects that I am attempting to compare to see if their content is the same. The function I am writing should have these two objects equal true, however, I am struggling with how to sort these so I can test for equal content (it's out of order). How would I solve this?  const obj1 = {   name: 'Sam',   age: 27,   description: [{     eyes: 'blue',     hair: 'brown'   }] }   const obj2 = {   age: 27,   name: 'Sam',   description: [{     hair: 'brown',     eyes: 'blue'   }] }


"No such file or directory" BUT the file actually exist! / Executable problems

I've been using Ubuntu (13.10) for a couple of months, and I really liked. But it crashed often and that's something that I didn't liked. I was able to run all my files in my terminal without any problem, like my favourite games. And also the executable files. I was able to run them perfectly.   Then elementary Luna OS came out and I decided to give it a try. When I installed was really quick, but after some days I realized that I couldn't open most of my files on the terminal. Just a few, I can't play games anymore because of that problem. Also, I can't open executable files.   So, I decided to reinstall Ubuntu, and guess what? I wasn't able to do nothing! my games and everything, I couldn't open them because the terminal didn't let me. Always displaying the message "no such file or directory" while the file actually exist.   Also tried in Linux mint, same thing. I've tried everything, can't do anything. Could some of you help me.  All of my desktops were x64 bits edition. Right now I'm running Linux mint 16 petra cinnamon desktop x64.   How to solve this?


Thunderbird Email application does not start

When I click on the Thuderbird Email icon I get the following error message: XML Parsing Error:undefined entity Location: chrome://messenger/content/messenger.xhtml Line Number 905,Column 3: <Key id="openLightningKey" --꘍


How to check the return value of the type() method in Python?

I'm trying to write a Python 3 function that will filter a list and pop() all items that are a string. But when I try to write the following function: def filter_list(l):     for i in l:         type_item = type(l[i])         if type_item == "class str":             l.pop(i)     return l  I get an error saying: File "/home/codewarrior/solution.py", line 3, in filter_list     type_item = type(l[i]) TypeError: list indices must be integers or slices, not str  I believe that the return of this method is not a str, but I haven't found any documentation that tells me how I can check if the return is a string or not. Thank you!


How do I bake chocolate chip cookies like Subway?

I want a chocolate chip cookie like the ones Subway has. Those cookies have a smooth top and chewy texture.  I have a recipe for 3/4 cup fat, 0.5 cup sugar 0,5 cup brown sugar, 3/4 cup flour, 1 egg, 2 tsp extract. I get a semi stiff dough, but also an airy cookie, not as dense like Subway. I use room temperature margarine.  I have tried to bake cookies with 2 eggs and with 1 egg, but they always come out wrinkly on top, not as stiff. Is it possible that using an egg and a yolk would work? (But wouldn't that waste a lot of whites if that's how they do it?)  I think as part of this I want a stiff dough, that'll leave the bowl clean, to minimize spread and keep the tops from getting wrinkly as stiffness will keep the the cookies from expanding and contracting. Is that true? If so, I'm afraid that if I add more flour to stiffen the dough will make the cookies cakey - is that the case? How would I avoid that?


Is it possible to have a geostationary satellite over the poles?

My understanding of orbital mechanics is very limited, but as I understand geostationary satellite, they stay in place by having an orbital speed corresponding to the spot they're orbiting over.  So my basic intuition tells me that it's not possible to have a geostationary satellite over the poles, since they're effectively standing still, and to my knowledge, a satellite must keep a certain velocity to keep from getting pulled down by gravity.  Am I missing something?


Why does Python treat variables as integers, and not allow decimals?

In some simple mathematics, here I am trying to get the percentage of targets which have been done from the total number.  The ones which have been done are positive.  In my understanding, the following mathematics should give me a percentage of 50, but running it, Python insists on giving me zero.  Why would that be?  Total =  2 Positives = 1 Percentage = (Positives/Total)*100 print ('Percentage is: ' + str(Stat) + '%\n' )  >>>Percentage is: 0%


Can I minimize a window into a box on Unity?

On Irix's  4Dwm, there was an ability to minimise windows into a box (contrary to the task bar used by modern window managers). I have seen this also on an old HPUX.  See the "console" square in the linked image:    Is it possible to accomplish on Ubuntu, either with a plugin or maybe some  window manager other than Unity?


How to find road distance between points from two shapefiles in QGIS

I am new to QGIS, but have to find the distance between centroids of NJ municipalities (which I have as a shapefile) and the nearest road sign which is also its own shapefile, along the roads of the state. I have three shapefiles: one road shapefile, and two point shapefiles and my goal is to find the road distance between points of the two point shapefiles. I have tried the RoadGraph plugin but I do not want to have to manually click each point since I have to know the nearest sign to each centroid first.


Size of cost raster in Least Cost Path plugin

When I run the Least Cost Path plugin in QGIS, its success is dependant upon the dimensions of the 'cost raster'. If the original DEM or subsequent 'cost raster' it too large then the operation seems to fail. With the successful example below, can anyone tell me what the "8765 * 7727" actually is/means?? It is not metres or kilometres. Is it pixels???  QGIS version: 3.8.3-Zanzibar QGIS code revision: 685d8b15d2 Qt version: 5.11.2 GDAL version: 2.4.1 GEOS version: 3.8.0-CAPI-1.13.1  PROJ version: Rel. 5.2.0, September 15th, 2018 Processing algorithm… Algorithm 'Least Cost Path' starting… Input parameters: { 'BOOLEAN_OUTPUT_LINEAR_REFERENCE' : False, 'INPUT_COST_RASTER' : 'E:/BU Volunteer/QGIS/Ians-Rift-Valley/10-overlayed-maps/least-cost-stuff/adama.tif', 'INPUT_END_LAYER' : 'E:\\BU Volunteer\\QGIS\\Ians-Rift-Valley\\10-overlayed-maps\\least-cost-stuff\\adama.gpkg|layername=adama', 'INPUT_RASTER_BAND' : 1, 'INPUT_START_LAYER' : 'E:/BU Volunteer/QGIS/Ians-Rift-Valley/10-overlayed-maps/least-cost-stuff/awash-start-4326.gpkg|layername=awash-start-4326', 'OUTPUT' : 'TEMPORARY_OUTPUT' }  The size of cost raster is: 8765 * 7727 Searching least cost path... Search completed! Saving path... Execution completed in 4058.56 seconds Results: {'OUTPUT': 'Output_least_cost_path_a74cf0f6_b4aa_4ee6_a876_ef6c26f4e164'}  Loading resulting layers Algorithm 'Least Cost Path' finished


How to create a directory within your home directory - Linux

I do not know how to create a directory within my Home directory.  I also need to name the directory A452.  How do I do this?


I have a theorem A and another one whose numbering is the numbering of A followed by a prime. However, I don't want the red box of the numbering for the second theorem, and this is the single place where I want to remove the box, that is, I want to keep the boxes for all other references. The example I have is as follows:  \documentclass[11 pt, a4paper]{article} \usepackage{amsmath,amssymb,amsthm,mathrsfs,amsfonts,dsfont} \usepackage{hyperref}  \newtheorem{thm}{Theorem}[section]  \newenvironment{thmprime}[1] {\renewcommand{\thethm}{\ref{#1}$'$}% \addtocounter{thm}{-1}% \begin{thm}} {\end{thm}}  \begin{document}  \begin{thm}\label{test} Test \begin{align}\label{eqn}  a^2  \end{align} \end{thm}  Equation \ref{eqn}  \begin{thmprime}{test} Test \end{thmprime}  \end{document}   Many thanks in advance!


USB Audio Device Loopback Through Speakers

I have a USB turntable which when plugged in to my Ubuntu 10.10 machine appears in the audio settings as an input device (USB PnP Audio Device Analog Stereo) like a microphone.  What I'd like to be able to do is have the sound for that audio device played back through the audio output (speaker or whatever). I'm not too worried if there's a slight delay between the audio coming in and it being played out through the speakers.  As far as I'm aware this is refereed to as software loopback. I can achieve exactly what I want if I open Audacity, enable software loopback and press record. Obvious this isn't ideal as I don't really want it recording what I'm playing all the time.  I know this is possible because of the Audacity example however I'd like to know if there's a way to do it without it recording. I've search around for a while for a piece of software that does this, however I couldn't get anything even close.  Any help would be greatly appreciated.


On page 9 of Linear Regression Analysis 2nd Edition of Seber and Lee there is a proof for the expected value of a quadratic form that I don't understand.  Let  $X = (X_i)$ be an $n \times 1 $ random vector and let $A$ be an $ n \times n$ symmetric matrix. If $\mathbb{E}[X] = \mu$ and $\operatorname{Var}[X] = \Sigma = (\sigma_{ij})$ then $\mathbb{E}[X^T AX] = \operatorname{tr}(A\Sigma) + \mu^T A\mu$  The problem I have is almost right out the gate, I can't see how $\mathbb{E}[X^T AX] = \operatorname{tr}(\mathbb{E}[X^T AX])$ I think I get the rest of the proof, but if someone here can't point me in the right direction on this part, I'd be forever grateful!


Find pdf of transformation of two random variables using CDF

Let $X,Y \sim$ Uniform$(0,1)$ be independent. Find the PDF for $X/Y$.  Let $Z=X/Y$. We want to find $F_z(z)=P(Z \leq z)=P(X/Y \leq z)$. We can make $Y$ super small with fixed $X$, and conversely we can make $X$ really small with fixed $Y$. Thus it appears to me that we have $0<z<\infty$.  I am struggling to find the subgraph of the unit square. We know that $X \leq Yz$. If $z = 1$, then we have a simple diagonal through the unit square. Increasing the value of $z$ shrinks what $Y$ can be since $X$ must be between $0$ and $1$. So we should see these lines fan out below the diagonal of the square as $z$ increases. Conversely, if $z$ approaches $0$, then we we limit the range of $X$, and so these lines fan out above the diagonal. What I am having trouble with is putting this all together and calculating the integral itself.


Conveyor animation for Powerpoint presentation

I need to create a powerpoint slide showing an animated 3D model of a conveyor belt. Just like this without the wheels inside...  I wanted to use a cube as the conveyor belt, which I expand to multiple segments using the array modifier.  All segments should then move along a curved path. Unfortunately, I come to the end of my abilities when trying to implement this animation in Blender. I think I am losing my mind :) My approach so far has been the following: Creat the path:  Draw a circle and stretch it to an oval Convert the circle to curve  Create the conveyor segments  Add a cube and resize it (the mesh should be the conveyor belt) Add Modifier Array to Mesh Enter the number of segments Add Modifier Curve  That's it. If I now select the conveyor belt and move it in Y direction, all segments move along the path. The tricky part is to get the whole thing to work as an animation in Powerpoint. As far as I know, animations in Blender have to be equipped with an armature, so that the animation works in Powerpoint.  Therefore I inserted an armature. Then I select the cube and the armature and press CTRL - P (with Automatic Weights). If I now move the armature in Y direction, the conveyor belt still runs along the path. After inserting the keyframes for the armature I export the file.  But the segments of the conveyor do not move along the path. What am I doing wrong? Thanks for the help and best regards Michael :)


changing highlighting in shading in TikZ

In TikZ, how do you change the position of the "highlight" in the shading of a circle, such as   \documentclass{article} \usepackage{tikz} \begin{document}     \tikz \shade[ball color=red] (0,0) circle (1); \end{document}    so that the highlight appears in the exact middle of the circle? The default position of the highlight seems to be a bit to the northwest.


Let $G=\left<a,b\right>$ be a finite group. What can I say about the order of $G$ with respect to the orders of $a$ and $b$?  Is it true that $|G|\leq |a||b|$, or are there any counterexamples?  What if $\{a,b\}$ forms a minimal generating set for $G$ (i.e. $\left<a\right>$,$\left<b\right>\ne G$)?


Changing desktop icon size in Ubuntu 19.04

I just went from 18.10 to 19.04 and the desktop icons and shortcuts are there but they are too large. Previously I could decrease their size from nautilus but now they seem to not respond to that and as far as I know, the desktop icons are no longer under nautilus.  I was wondering if there is a way to decrease the size of the icons already on my desktop instead of installing some new extension to create new icons and then resize them.


How can I manage my genealogy data on Ubuntu?

I use several genealogy applications on Windows.  What applications for genealogy are available on Ubuntu and how would I move my current genealogy data to Ubuntu?


My website is hosted in the US and I was wondering if a CDN will help improve my SEO with search engines.


How to solve "insufficent space on the device" error on Samsung Captivate

I have a Samsung Captivate, running the stock Froyo ROM, rooted.  When I try to install a large app from the Market, I get the error "insufficent space on the device", for apps of ~40 MB, with 700+MB free.  I first noticed it with "Jelly Defense" on Google's Christmas-week sale, but you can see it for yourself if you try the free "Reiner Knizia's Labyrinth" which is also quite large.  This is a common problem -- just Google it and you'll see dozens of posts around the Internet going back almost a year. From those posts, I've tried two free apps that are supposed to help, "Market Fix" and "Cache Fixer", but neither has done the trick yet.  As I understand it, both are supposed to re-mount /cache as a loopback file on the SD card.  I don't know why they don't work.  If anybody has fixed this specifically on the i9000 series (SGS1, Captivate, Fascinate, etc), please let me know how!


Which is bigger between $2018^{2019}$ or $\ 2019^{2018}\ $?  When taking logs of both sides and  I get:   $2019\log(2018)\ $ and $\ 2018 \log(2019)$  I know $\log 2019\gt \log 2018$ so does this mean that $2019^{2018}$ is the biggest one? And did I do it properly?


Validate the name of objects in the creation of stored procedures in SQL SERVER

When I execute the command below no SQL SERVER 2017:  Create or Alter Procedure stp_Teste01  as  select name, type_desc  from sys.objectsx go   SQL SERVER does not validate if the SYS.OBJECTSX object exists. Only when I run the procedure that SQL Server presents the error message.  EXECUTE STP_TESTE01 GO Msg 208, Level 16, State 1, Procedure stp_Teste01, Line 3 [Batch Start Line 11] Invalid object name 'sys.objectsX'.   Why does it not validate at the creation stage of the stored procedure?  If you place the name of the TYPE_DESCX column, SQL Server displays the error message.  Create or Alter Procedure stp_Teste01  as  select name, type_descX  from sys.objects go  Msg 207, Level 16, State 1, Procedure stp_Teste01, Line 3 [Batch Start Line 5] Invalid column name 'type_descX'.   Is it not in the ALGEBRIZER phase that SQL Server validates the existence of objects in the database and the creation of the procedure does not execute the PARSE and ALGEBRIZER phase?


How do I find the Galois group of $x^4-5$ over $\mathbb{Q}(i)$, $\mathbb{Q}(\sqrt5)$ and $\mathbb{Q}(\sqrt{-5})$? I've managed to do so over $\mathbb{Q}$ but I don't know how to find the others.  I'd appreciate any help. Thanks!


How does gravity change nearing the core in free fall?

The Pole to Pole Mole Hole-  If there were to somehow be a cylinder going from the North to South Poles, all the way through Earth, then what would happen halfway down (The Core). If something fell down this hole then as it nears what used to be the core, how would it be effected by gravity (This would be free fall)? Nearing the core you would be under more gravity so would you slow to a stop? Or would you get flung out the other side at hundreds of miles an hour? Or maybe you would just have just enough force to be on you feet on the other sides like in some movie. And please do not just comment to yell at me that you would die under pressure, heat or that the hole is impossible.


I wrote this post instead of a comment:      It doesn't let you comment because you are using a different account now from the one with which you asked the question. Use the contact form to request account merge.   That's the account I started with:   Somehow it forgot all my data and created a new one when I clicked the link in the email?? Your workflow for new users is really messed up, might be worth asking on UX how to improve it.


In the opening credits of a TV show, why do some people get an "and" before their name?

In the opening credits of a TV show, I have seen that sometimes on the last actor/actress, they will get an "and" before their name. An example that comes to mind is on It's Always Sunny In Philadelphia, Frank is credited with "and Danny DeVito". Why do they do that, what is the purpose of it? What determines if a cast member is worthy of the "and"? I know there is  question about "with"; do the same rules apply for "and"?


Can't access my Windows 7 Hard Disk from Ubuntu 14.04 LTS

Alright, so I really need help now.  I am not gonna tell the story about how my Windows broke, but what I need is to transfer some of my files which I had on Windows through Linux to a USB Flash Drive. But I end up with this error while trying to go into my 1 TB Volume:  Error mounting /dev/sda2 at /media/ubuntu/1E48BCAD48BC85551: Command-line `mount -t "ntfs" -o "uhelper=udisks2,nodev,nosuid,uid=999,gid=999,dmask=0077,fmask=0177" "/dev/sda2" "/media/ubuntu/1E48BCAD48BC85551"' exited with non-zero exit status 13: ntfs_attr_pread_i: ntfs_pread failed: Input/output error Failed to read NTFS $Bitmap: Input/output error NTFS is either inconsistent, or there is a hardware fault, or it's a SoftRAID/FakeRAID hardware. In the first case run chkdsk /f on Windows then reboot into Windows twice. The usage of the /f parameter is very important! If the device is a SoftRAID/FakeRAID then first activate it and mount a different device under the /dev/mapper/ directory, (e.g. /dev/mapper/nvidia_eahaabcc1). Please see the 'dmraid' documentation for more details.   My Windows is not working properly, and I NEED to transfer those files. PLEASE help me! Is there any code I can use? Don't ask me about the repair disk of Windows, it didn't work since it got extremely slow and I left it "loading" on a windows background with my mouse for the night.  All I need is to transfer files from my 1 TB Volume onto my flash drive. I know what to do next, this is just all I need.


Hypothetical equation (modulo a power of two) and the value

We have hypothetical equation: $2^{b} \% k = z$.  Assume that we know $z$, $b$ and $k$. So everything! We want to know only if the above equation is true.  I do not want to use the exponentiation modulo - I am looking for some faster method. I do not need to know the exact value of $ 2 ^ {b} \% k $. I just want to know if it is $ z $.  It can be done without trivial exponent modulo?    Edit:  My mistake: $b = k$:  $2^{b} \% b = z$.


Concerning a previous possible tachyon observation?

A few years ago there was a story about the Large Hadron Collider where a possible tachyon  was supposedly observed. It was later shown it didn't occur yet the incident made me think. If a large experiment using extreme amounts of energy trying to duplicate some processes or events of the 'distant' past , would the intense amount of energy  in this 'early' Universe experiment create a situation where the speed of light was different?? If a particle was observed emanating from this experiment and it seemed superluminal could this be due to a different speed of light measurement due to this phenomenon.


When have you come upon the halting problem in the field?

When have you ever personally come upon the  in the field? This can be when a co-worker / boss suggested a solution which would violate the fundamental limits of computation, or when you realized yourself that a problem you were trying to solve was, in fact, impossible to solve.  The most recent time I came up with it was when studying type checkers. Our class realized that it would be impossible to write a perfect type checker (one that would accept all programs that would run without type errors, and reject all programs that would run with type errors) because this would, in fact, solve the halting problem. Another was when we realized, in the same class, that it would be impossible to determine whether a division would ever occur by zero, in the type-checking stage, because checking whether a number, at run-time, is zero, is also a version of the halting problem.


Program doesn't compile when I include .h, works when I include .cpp

I have these three files, main.cpp, DynamicArray.cpp, DynamicArray.h. In both cpp files I include DynamicArray.h and I get the following errors.  $ g++ main.cpp DynamicArray.cpp  /tmp/ccDGRYws.o: In function `testDynamicArray()': main.cpp:(.text+0x11): undefined reference to `DynamicArray<int>::DynamicArray()' main.cpp:(.text+0x1d): undefined reference to `DynamicArray<int>::DynamicArray()' main.cpp:(.text+0x39): undefined reference to `DynamicArray<int>::~DynamicArray()' main.cpp:(.text+0x5a): undefined reference to `DynamicArray<int>::add(int)' main.cpp:(.text+0x72): undefined reference to `DynamicArray<int>::size()' main.cpp:(.text+0xb8): undefined reference to `DynamicArray<int>::~DynamicArray()' main.cpp:(.text+0xc9): undefined reference to `DynamicArray<int>::~DynamicArray()' collect2: error: ld returned 1 exit status   When I change the DynamicArray.h in  main.cpp to DynamicArray.cpp it works fine. Why is it not working with the .h?  main.cpp  #include <iostream> #include <assert.h>  #include "DynamicArray.h"  void testDynamicArray(){      DynamicArray<int> array1;     array1 = DynamicArray<int>();      int initialSize = 10;        for (int i = 0; i < initialSize; i++) {         array1.add(i);     }      assert(array1.size() == initialSize);      std::cout << "All tests for DynamicArray pass." << std::endl; }    int main(){     testDynamicArray(); }   DynamicArray.cpp  #include "DynamicArray.h" #include <iostream>  template <typename T> DynamicArray<T>::DynamicArray(){     numElements = 0;     arraySize = 10;     theArray = new T[arraySize]; }  template <typename T> DynamicArray<T>::~DynamicArray(){     delete[] theArray;     }  template <typename T> int DynamicArray<T>::size(){     return numElements; }  template <typename T> bool DynamicArray<T>::isEmpty(){     return (numElements == 0); }  template <typename T> void DynamicArray<T>::increaseSize(){         T* tempArray = new T[arraySize * 2];          for(int i = 0; i <= numElements; i++) {             tempArray[i] = theArray[i];         }          delete[] theArray;         theArray = tempArray;          arraySize *= 2; }  template <typename T> void DynamicArray<T>::insert(T newElement, int index){     if (numElements == arraySize) {         increaseSize();     }      for (int i = numElements; i >= index ; i--) {         theArray[i] = theArray[i-1];     }      theArray[index] = newElement;     numElements++; }  template <typename T> void DynamicArray<T>::add(T newElement){     if(numElements == arraySize)         increaseSize();      theArray[numElements] = newElement;      numElements++; }  template <typename T> T DynamicArray<T>::get(int index){     return theArray[index]; }  template <typename T> bool DynamicArray<T>::deleteIndex(int index){      if(index < 0 || index >= numElements)         return false;      for (int i = index; i < numElements-1; i++)      {         theArray[i] = theArray[i+1];     }      numElements--;      return true; }   DynamicArray.h  #ifndef DYNAMICARRAY #define DYNAMICARRAY  template <typename T> class DynamicArray{     private:     T* theArray;     int numElements;     int arraySize;     void increaseSize();      public:     DynamicArray();     ~DynamicArray();     int size();     bool isEmpty();     void insert(T newElement, int index);     void add(T newElement);     bool deleteIndex(int index);     T get(int index); };  #endif


Prove that $\lim_{x \to y} \frac{x^k-y^k}{x-y} = k*y^{k-1}$ for $y\in\mathbb R$ and $k\in\mathbb N$

how can I prove the following: Prove that $$ \lim_{x \to y}  \frac{x^k-y^k}{x-y} = ky^{k-1} $$ for a fixed $y\in\mathbb R$ and $k\in\mathbb N$. I already tried a lot but somehow I don't come to the correct conclusion


How to append to definition of a macro which has arguments?

I’ve been using \let\oldsomething\something\renewcommand*something{\oldsomething ...} in a couple places, but it’s tedious and I guess prone to errors if I were to try to redefine again with the same auxiliary macro.  After learning about \g@addto@macro I was happy for a while. Then arose the need to append to a command which has arguments:  \newcommand*{\hello}[1]{Hello #1} \g@addto@macro{\hello}{!} \show\hello   That sequence prints:  > \hello=macro: Hello !.   So, the argument seems to disappear. The result I was attempting is:  > \hello=macro: ->Hello #1!.   Is there some easy way to change the middle line to obtain this, or is it back to the old way for macros with arguments?


"Cannot find an appropriate constructor for type Microsoft.SharePoint.SPRoleAssignment" in PowerShell

I'm trying to add a SharePoint group to a specific list that exists on all the sites in a collection. I would think this would be easier but I'm having difficulties. Inheritance is already broken on the list.   Below is my code and then the error I'm getting.  $siteNumbers = "2210" $listsOnSite = "QWERTY"  Foreach($wnl in $siteNumbers)     {     $rootWeb = (Get-SPWeb ("http://url/to/site/" + $wnl))       Foreach($lst in $listsOnSite)       {     $list = $rootWeb.Lists[$lst]     $group = $rootWeb.Groups["Global Read-Only QWERTY"]     $role = $rootWeb.RoleDefinitions["Read"]      $roleAssignment = New-Object Microsoft.SharePoint.SPRoleAssignment($group)     $RoleAssignment.RoleDefinitionBindings.Add($role)     $rootWeb.RoleAssignments.Add($RoleAssignment)     $list.RoleAssignments.Add($roleAssignment)     $list.Update()     }     $rootWeb.Update()     }      New-Object : Constructor not found. Cannot find an appropriate   constructor for type Microsoft.SharePoint.SPRoleAssignment. At line:9   char:33   +     $roleAssignment = New-Object <<<<  Microsoft.SharePoint.SPRoleAssignment( $group)       + CategoryInfo          : ObjectNotFound: (:) [New-Object], PSArgumentExce    ption       + FullyQualifiedErrorId : CannotFindAppropriateCtor,Microsoft.PowerShell.C   ommands.NewObjectCommand      Exception calling "Add" with "1" argument(s): "The permission level   specified i s already added to the collection." At line:10 char:47   +     $RoleAssignment.RoleDefinitionBindings.Add <<<< ($role)       + CategoryInfo          : NotSpecified: (:) [], MethodInvocationException       + FullyQualifiedErrorId : DotNetMethodException      You cannot call a method on a null-valued expression. At line:12   char:30   +     $list.RoleAssignments.Add <<<< ($roleAssignment)       + CategoryInfo          : InvalidOperation: (Add:String) [], RuntimeExcept    ion       + FullyQualifiedErrorId : InvokeMethodOnNull      You cannot call a method on a null-valued expression. At line:13   char:17   +     $list.Update <<<< ()       + CategoryInfo          : InvalidOperation: (Update:String) [], RuntimeExc    eption       + FullyQualifiedErrorId : InvokeMethodOnNull


What would the effect be of a small black hole colliding with the earth?

If a small black hole (say about .1 mm radius or 1% of Earth's mass) came flying along at the speed of a comet or higher and impacted the earth, what would happen? Would it pass through the earth (and atmosphere) with minimal damage? Would it leave a crater (entry or exit?) Would it create a big enough shock wave to significantly damage the earth? Would it be captured and wander around inside the earth?  I read a book a few years ago with this as the primary part of the plot, and I have wondered about the physics ever since.


Emails send from some of the addresses in one domain are marked as spam by multiple email clients. Since just few addresses within the domain are marked as spam, I do not think it is a domain problem, or can it be?  I checked the email header, but do not have any experience with this and I don't know what to do next:  Thunderbird  X-Spam-Flag: YES X-Spam-Score: 6.63 X-Spam-Level: ****** X-Spam-Status: Yes, score=6.63 tagged_above=-10 required=5     tests=[ALL_TRUSTED=-1, BAYES_00=-1.9, DNS_FROM_AHBL_RHSBL=2.699,     HTML_MESSAGE=0.001, RCVD_IN_PBL=3.335, RCVD_IN_RP_RNBL=1.31,     RCVD_IN_SORBS_DUL=0.001, RDNS_NONE=0.793,     SHORT_HELO_AND_INLINE_IMAGE=1.39, URIBL_BLOCKED=0.001] autolearn=no   Yahoo  X-YahooFilteredBulk: 217.11.253.114  Received-SPF: none (domain of "ourdomain" does not designate permitted sender hosts)


How to disable showing log on terminal in latex

How do I disable showing all information to the terminal?  Is possible to only show errors not log,warnings etc.?


How to calculate $f(x)$ in $f(f(x)) = e^x$?

How would I calculate the power series of $f(x)$ if $f(f(x)) = e^x$?  Is there a faster-converging method than power series for fractional iteration/functional square roots?


Why is the return String from function different than a simple echo?

I'm struggling around with this german umlaut problem:  include.php  function test() {   $Ausgabe = "äöü";   return $Ausgabe; }   echo.php (html meta charset="utf-8")  require_once('include.php'); echo 'Content from function: '.test(); echo '<br>'; echo 'Direct: äöü';   Delivers:  Content from function: ���  Direct: äöü  Why is there a difference?


why would curl and wget result in a 403 forbidden?

I try to download a file with wget and curl and it is rejected with a 403 error (forbidden).  I can view the file using the web browser on the same machine.  I try again with my browser's user agent, obtained by . I do this:  wget -U 'Mozilla/5.0 (X11; Linux x86_64; rv:30.0) Gecko/20100101 Firefox/30.0' http://...   and  curl -A 'Mozilla/5.0 (X11; Linux x86_64; rv:30.0) Gecko/20100101 Firefox/30.0' http://...   but it is still forbidden. What other reasons might there be for the 403, and what ways can I alter the wget and curl commands to overcome them?  (this is not about being able to get the file - I know I can just save it from my browser; it's about understanding why the command-line tools work differently)  update  Thanks to all the excellent answers given to this question. The specific problem I had encountered was that the server was checking the referrer. By adding this to the command-line I could get the file using curl and wget.  The server that checked the referrer bounced through a 302 to another location that performed no checks at all, so a curl or wget of that site worked cleanly.  If anyone is interested, this came about because I was reading  page to learn about embedded CSS and was trying to look at the site's css for an example. The actual URL I was getting trouble with was  and the curl I ended up with is  curl -L -H 'Referer: http://css-tricks.com/forums/topic/font-face-in-base64-is-cross-browser-compatible/' http://cloud.typography.com/610186/691184/css/fonts.css   and the wget is   wget --referer='http://css-tricks.com/forums/topic/font-face-in-base64-is-cross-browser-compatible/' http://cloud.typography.com/610186/691184/css/fonts.css   Very interesting.


Orange “aura” around people/objects in photo, usually present with older cameras?

I’m not sure if this is the right place to ask but I’ve been unable to figure out what exactly this is. It’s an effect, seemingly unintentional, that makes people and things have orange blurs around them, making them look like their souls are leaving their bodies or something (haha). I say it’s from “old” cameras because the instances I’ve seen them had been captured in the year 2005. My best guess is that this is caused by the people moving around too much and the camera lagging on their previous position, or some other processing error.  I’ve attached some photos of a Flyleaf concert that hopefully demonstrate what I mean.


I upgraded my ubuntu to 12.04 through software center and it did not go well. The problem is I'm using this machine after a long time that I don't remember the previous version no (definitely greater than 10.0)  Machine: Asus A8ESeries  The font colors changed to white, it did not detect ext hard drives. I did an upgrade from terminal and now I get the following problems:   The text font color on all windows changed to white The track pad did not work (Which I fixed using this thread ) Network menu not showing wireless option itself. My output for "dmesg | grep iwl" and rfkill list all are blank External hard disk not detecting. I need to back up my files before upgrading again. unity one launcher not working.  no menus at the top right corner and many more failures.    I really need to back up my files which is the most important task. Also get my wireless working. Please kindly help.  Regards, psun


As an antonym for exoticize, would you favor de-exoticize or deexoticize?  Google currently finds ~2970 results for the hyphenated version and ~440 results for the unhyphenated, but both of those numbers are so small that I wouldn't call that conclusive.  An example sentence: This novel deexoticizes/de-exoticizes Africa to the Western reader.  A general rule can be found at:   There, it is explained that prefixes are generally not hyphenated, but that there is a common exception of hyphenating prefixes when a vowel would be repeated otherwise. However, in this case, exoticize is a pretty stylized word, and I want to confirm that, in working with it, I should follow the same conventions as I would for more standard words.


Low budget alien movie about the Earth being cooked

I’m looking for an alien movie I watched years ago, mid to late 2000’s about the Earth being cooked or heated up by aliens. The poster is a reflection of the Earth heating up with an orange glow on an aliens eye. It was a low budget movie and I think the one I watched was pirated from China. Again low budget, bad quality and the name could’ve been something worthy he word scorch or something like that. The alien in the movie had legs with knees that went inwards and it had red eyes.


Why are there so many users named "user"?

Are the deleted users automatically renamed to user<random number>, e.g. user354353, or user240249 or are they actually naming their accounts like this?


Unable to install add-ons to Blender 2.82a and Blender 2.9 on a Mac

I am at total loss and YouTube/Google offer nothing to solve this issue.  I downloaded the .zip file for Edge-Flow Master from Github and there is no way to actually install the files.    I've opened up Blender 2.82a and 2.9a) and go through the usual route of opening   Edit>Preferences>Add-ons ensuring Official/Community/Testing are active then click on Install an addon.    I then navigate to the folder in my Downloads but all that is there is; Pyhthon scripts, a doc folder containing jpg and psd files, a License text file and a Readme Text File (neither of the latter will open on my iMac 2011)    I've gone through clicking on each possible python script and clicking install and nothing happens.  So I searched YouTube and there are very few helpful videos or websites going through the process, but I did find one very very annoying video that eventually got to opening Blender in a finder window using Show Package Content then navigating to the addon via Contents>Resources>2.82>Scripts>Addons and then I copied the files to this location rebooted Blender and yet still nothing when I search for the addon proving it's not installed.  So just how am I to install addons to Blender without a .zip file to install from (Apparently it just dumped the files to my download folder I assume it unzipped itself in doing that)?   I don't know enough about addons or python to know how to properly get Blender to recognise these files there's no installer and no .zip file and directly coping the files to the addon folder does nothing.  So I am at a lost.  I've used Blender years ago but I don't remember if I ever came across this issue before, or maybe I did but have forgotten.    I'd like to purchase some modelling addons but I'm not laying down hard cash until I can resolve this addon installation propblem. This isn't the first addon Ive had this problem with I also downlaoded WrappingTools - same issue, no way to install it.


.focus() not firing for elements added to the DOM with JQuery

I'm trying to use .focus () after adding more input fields with jQuery, but it only works with the input field already present in HTML and not with the ones added.  For example, if I click on the input field that is in the form, an alert will appear, but if I add more input fields and click on them, nothing will appear.  Is there a solution? Thanks! :)       $(document).ready(function(){          var cont = 1;         $( "#add-campo" ).click(function() {             cont++;             $( '
 Campo:  <input type="text" name="titulo[]" placeholder="Digite aqui"> <button id="'+cont+'" class="btn-apagar"> - </button>
' ).appendTo( "#formulario" );         });          $('form :input').focus(function() {             alert( "Handler for .focus() called." );         });          $( "form" ).on( "click", ".btn-apagar", function() {             var button_id = $( this ).attr("id");              $( '#campo' +button_id+'' ).remove();         });     });
ADICIONAR CAMPOS
 <form id="add-pub" method="POST">

             campo:              <input type="text" name="titulo[]" placeholder="Digite aqui">             <button type="button" id="add-campo"> + </button>

         <input type="button" name="PubRot" id="PubRot" value="PUBLICAR">
 </form>


broadcom dw1530. The wifi doesn't work anymore

My wifi worked great on Ubuntu, until today where my wifi doesn't work anymore after turning on my pc. I don't see the wifi tab in the settings. I am running a dual boot and wifi still works on Windows. Wi-fi card: broadcom dw1530 wireless-n wlan half-mini card What should I do to fix the problem? Edit: Output of lspci -knn | grep Net -A3 : 00:19.0 Ethernet controller [0200]: Intel Corporation 82579LM Gigabit Network Connection (Lewisville) [8086:1502] (rev 04)     DeviceName:  Onboard LAN     Subsystem: Dell 82579LM Gigabit Network Connection (Lewisville) [1028:0493]     Kernel driver in use: e1000e     Kernel modules: e1000e 00:1a.0 USB controller [0c03]: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 [8086:1c2d] (rev 04) -- 02:00.0 Network controller [0280]: Broadcom Inc. and subsidiaries BCM43228 802.11a/b/g/n [14e4:4359]     Subsystem: Dell Wireless 1530 Half-size Mini PCIe Card [1028:0011]     Kernel modules: bcma 0a:00.0 SD Host controller [0805]: O2 Micro, Inc. OZ600FJ0/OZ900FJ0/OZ600FJS SD/MMC Card Reader Controller [1217:8221] (rev 05)  Edit 2: lspci -knn | grep Net -A3 00:19.0 Ethernet controller [0200]: Intel Corporation 82579LM Gigabit Network Connection (Lewisville) [8086:1502] (rev 04)     DeviceName:  Onboard LAN     Subsystem: Dell 82579LM Gigabit Network Connection (Lewisville) [1028:0493]     Kernel driver in use: e1000e     Kernel modules: e1000e 00:1a.0 USB controller [0c03]: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 [8086:1c2d] (rev 04) -- 02:00.0 Network controller [0280]: Broadcom Inc. and subsidiaries BCM43228 802.11a/b/g/n [14e4:4359]     Subsystem: Dell Wireless 1530 Half-size Mini PCIe Card [1028:0011]     Kernel driver in use: wl     Kernel modules: bcma, wl


How can I change the default text color in Mail?

How can I change the default text color (black to dark grey) in Mail on Lion?


Why would you create a class with one single member which is an operator()?

I have tried to find out -out there- a good technical reason for defining a class which contains only one member and this member happens to be a operator().  I stumbled upon someone who -for whatever the reason- created a namespace containing a couple of classes, but each class contains only one operator() as a member.  It is clear to me that these classes might then be used as if they were methods (very likely), but why is this a good technical approach (I assume there is a good one), rather than simply defining a set of different methods within a singleton class which in this particular case would belong to the namespace I mentioned lines above.  The namespace looks something like:  namespace myNamespace {    class ClassA {    public:       void operator()();    };     class ClassB {    public:       int operator()(arg1, arg2);    };     ... }   Is this simply a matter of personal taste/style or is this the expression of advance/sophisticated design? I assume this design encompass some wise knowledge that I haven't gathered yet, but on the other hand I haven't found a piece of article or question discussing this - which makes me doubt about such "wise knowledge" in the design.  What does the experts here have to say?  Thanks in advance!  EDIT  Hello again! I accept this question to be a REPEATED question, whose answer is found .  The term Functor was unknown to me and while trying to find an answer to my doubt (prior to this question's submission), I did not see any references to this term.  I still accept the answer from SergeyA, because his answer introduced me to the term and his explanation is answering my question. His answer -from my point of view- is extended by the answer found in the link I stated lines above.  Thanks!


Show $\det(A + B) \geq 0$ implies $\det(A^k + B^k) \geq 0$ if $A, B$ commute

Let $A, B$ be two real $n\times n$ matrices that commute. Assume $\det(A + B) \geq 0$. Show then that $\det(A^k + B^k) \geq 0$ for all $k \geq 1$.  I believe what must happen is find some factorization of $A^k + B^k$ using commutativity of $A, B$. then we may find some squared terms, which would imply that the determinant is greater than zero. Not sure what factorizations would help.  Or perhaps use the fact the $A, B$ can be simultaneously put in upper triangular form by commutativity.


I have seen many proofs about a prime element is irreducible, but up to now I am thinking whether this result is true for any ring.    Recently, I got this proof:  Suppose that $a$ is prime, and that $a = bc$. Then certainly $a\mid bc$, so by definition of prime, $a\mid b$ or $a\mid c$, say $a \mid b$. If $b = ad$ then $b = bcd$, so $cd = 1$ and therefore $c$ is a unit. (Note that $b$ cannot be $0$,for if so, $a = bc = 0$, which is not possible since $a$ is prime.) Similarly, if $a\mid c$ with $c = ad$ then $c = bcd$,  so $bd = 1$ and $b$ is a unit. Therefore $a$ is irreducible.  I think with the above proof we do not need the ring to be an integral domain. If this is the case then I will stop doubting, else, I am still in it.  Can somebody help me out?


How to bulkify the soql query in this trigger?

I have been correctly informed by people who know what they are talking about that I should bulkify this code. The code does what it should but needs to be more efficient. Can anyone give concrete code examples what needs to done?  trigger trgr_Check_Duplicate_Roles on Key_Staff_People__c (before insert,before update) {       for (Key_Staff_People__c rsp: Trigger.new)          {               List <Key_Staff_People__c> rcrd = [SELECT Contact__c, Role__c FROM Key_Staff_People__c                                                  WHERE Contact__c = :rsp.Contact__c AND Role__c = :rsp.Role__c];               if (rcrd.size() > 0)             {                 if (rsp.Role__c <> Null && rsp.Role__c <> 'Other' )                 {                     if((Trigger.isUpdate && rcrd[0].Role__c <> Trigger.oldMap.get(rsp.Id).Role__c) || Trigger.isInsert)  trigger.new[0].addError('A contact with the role "'+rsp.Role__c+'" already Exist. Only the role "Other" may be assigned to multiple Key Staff People.');                                     }             }         } }


I have been reading and heard Google Pixel owner get unlimited free storage, but how? How Google Pixel owner register the unlimited free storage? I want to know if is register automatically when you buy the phone, or there is some code you can enter.


Why is there no dialogue options for Serana to follow me?

For some odd reason I can't get Serana to follow me and now there is no option for her to follow me when I open dialogue options. I need her though to finish the vampire quest line. I have tried attacking her, waiting, magic, everything.


If an exception occurs inside a "using" block, is the Dispose method called?

In C#, if an exception occurs inside a "using" block, does the Dispose method get called?


How do you update an imported script in the Python interpreter?

I have a script that I am in the process of debugging. I've imported it using:  import foo   Then I update foo. After I do "import foo" again, nothing is changed. How do I update it without needing to exist the interpreter and reenter? Furthermore, if there are other packages that depend on it, how do I update them to use the newest version?


JavaFx TableView, Cant retrieve data from mysql database to Table

Been getting an error at the line where I used "while (this.resultSet.next())" I'm new to javafx, still studying and watching youtube tutorials, unfortunately I can't find a video on how to fix this. The data from my database wont populate the table  Here's the error:  Caused by: java.lang.NullPointerException     at sample.TableViewController.Save(TableViewController.java:73)     ... 120 more   package sample;  import com.mysql.jdbc.ResultSet; import javafx.collections.FXCollections; import javafx.collections.ObservableList; import javafx.event.ActionEvent; import javafx.fxml.FXML; import javafx.fxml.Initializable; import javafx.scene.control.TableColumn; import javafx.scene.control.TableView; import javafx.scene.control.cell.PropertyValueFactory;  import java.net.URL; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.SQLException; import java.util.ResourceBundle; import java.util.logging.Level; import java.util.logging.Logger;  public class TableViewController implements Initializable {      @FXML     private TableView<ModelTable> table;      @FXML     private TableColumn<ModelTable, String> ID;      @FXML     private TableColumn<ModelTable, String> FrstName;      @FXML     private TableColumn<ModelTable, String> LstName;      @FXML     private TableColumn<ModelTable, String> GS;      @FXML     private TableColumn<ModelTable, String> Grade1;      @FXML     private TableColumn<ModelTable, String> Grade2;      @FXML     private TableColumn<ModelTable, String> Grade3;      @FXML     private TableColumn<ModelTable, String> Grade4;      @FXML     private TableColumn<ModelTable, String> Grade5;      @FXML     private TableColumn<ModelTable, String> Grade6;      Connection con = null;     PreparedStatement preparedStatement = null;     ResultSet resultSet = null;     ObservableList<ModelTable> oblist = FXCollections.observableArrayList();      @Override     public void initialize(URL url, ResourceBundle resourceBundle) {      }      public void Save(ActionEvent event) {         try {             String query = "Select * from `records`";             con = DriverManager.getConnection("jdbc:mysql://localhost/records", "root", "");             preparedStatement = con.prepareStatement(query);             preparedStatement.executeQuery();             while (this.resultSet.next()) {                 oblist.add(new ModelTable(resultSet.getString("ID"), resultSet.getString("FrstName"), resultSet.getString("LstName"), resultSet.getString("GS"), resultSet.getString("Grade1"), resultSet.getString("Grade2"), resultSet.getString("Grade3"),resultSet.getString("Grade4"), resultSet.getString("Grade5"), resultSet.getString("Grade6")));             }              ID.setCellValueFactory(new PropertyValueFactory<>("ID"));             FrstName.setCellValueFactory(new PropertyValueFactory<>("First Name"));             LstName.setCellValueFactory(new PropertyValueFactory<>("Last Name"));             GS.setCellValueFactory(new PropertyValueFactory<>("Grade/Section"));             Grade1.setCellValueFactory(new PropertyValueFactory<>("Grade1"));             Grade2.setCellValueFactory(new PropertyValueFactory<>("Grade2"));             Grade3.setCellValueFactory(new PropertyValueFactory<>("Grade3"));             Grade4.setCellValueFactory(new PropertyValueFactory<>("Grade4"));             Grade5.setCellValueFactory(new PropertyValueFactory<>("Grade5"));             Grade6.setCellValueFactory(new PropertyValueFactory<>("Grade6"));               table.setItems(oblist);          } catch (SQLException ex) {             Logger.getLogger(TableViewController.class.getName()).log(Level.SEVERE, null, ex);         }     } }


Show that if $K_9 $is coloured red and blue and contains no red triangle and no blue $K_4$, then every vertex must have red degree $3$ and blue degree $5$.  I have absolutely no idea how to proceed :(


I'm trying to prove the following inequality,   $$ \rho(AB) + \rho(BC) \le \rho(B) + \rho(ABC) $$  where $A, B, C \in L(V)$, $V$ is a finite-dimensional vector space and $\rho(A)$ means the rank of the linear operator $A$.  I know that $\min(\rho(AB), \rho(BC)) \le \rho(B)$. So I tried to prove that $\max(\rho(AB), \rho(BC)) \le \rho(ABC))$ but couldn't get anywhere.  Any hint is appreciated, thanks.


I am a novice LaTeX user and trying to create a table similar to this one:    I need circles where horizontal and vertical lines intersect but could not figure out how to do it. Will you please suggest me a way forward?  Thank you. Here is my code  \documentclass{beamer} \usetheme{Berlin} \usecolortheme{beaver} \setbeamertemplate{footline}[frame number] \setbeamertemplate{itemize item}[circle] \setbeamertemplate{enumerate item}[circle]  \setbeamertemplate{navigation symbols}{} \setbeamertemplate{footline}[frame number] \usepackage{multicol}  \begin{document} \begin{frame}{Literature} \label{specific literature} \begin{tabular}{ r r | c l }      Eren et al., (2019) &  & & \\      \cline{2-2}     & & &  \\     Berrill et al., (2018) & & & \\      & & & \\     Lee et al., (2014) & & & Empirical Studies \\      & & & \\     Ayyagari and Kosová (2010) & & & \\      & & & \\     De Backer and Sleuwaegen (2003)& & & \\      & & & \\      & & &  \\     Markusen and Venables (1999) & & & \\      & & & \\     Rodrìguez-Clare (1996)  & & & Theoretical Studies  \\      & & & \\     Grossman (1984) & & & \small    \hyperlink{literature}{\beamerskipbutton{Literature}} \\  \end{tabular} \end{frame} \end{document}


Filesystem shows /dev/nvme0n1p1 instead of /dev/sda

I installed a dual boot of Ubuntu 16.04 (Windows being my other OS) two months ago to try it out. I want to allot more space to it on my hard drive. I was looking up tutorials, and I noticed that my filesystem names don't look anything like those in the tutorials. For example:  df -h   outputs:    How would I allot more space to Ubuntu (in layman's terms)?


Add custom search engines on Chrome for Android

One of the most powerful productivity tools I use on Chrome is . However, I was wondering how I can do the same thing on Chrome for Android? I went through the settings on Chrome for Android, but understandably it doesn't have that feature. Ideas?


Can the guidance on the tag wiki edit page be improved?

The tag wikis on a lot of Stack Exchange sites can be pretty abysmal at times. There are numerous instances of members , but even when it's not straight-up copypasta, the vast majority of tag wiki edit suggestions I see are from people who honestly don't "get it". It doesn't help that these are named wiki, because everybody automatically associates that with Wikipedia and/or the kind of content that you would see on Wikipedia. At the very least, it would help to have better information on the editing page so that we're not constantly having to reject edits and refer people to the . I believe that the aforementioned guidelines were posted twice on the blog, although I can't remember the other occasion when it was posted. Specifically I'm thinking of this part:   Avoid generically defining the concept behind a tag, unless it is highly specialized. The “email” tag, for example, does not need to explain what email is. I think we can safely assume most internet users know what email is; there’s no value in a boilerplate explanation of email to anyone. Concentrate on what a tag means to your community. For “email” on Server Fault, mention the server aspects of email including POP3, SMTP, IMAP, and server software. For “email” on Super User, mention desktop email clients and explicitly exclude webmail, as that would be more appropriate for webapps.stackexchange.com.   I think this is what people need to hear about tag wikis, not the advice that's actually on the edit page:  The tag wiki excerpt is a brief plain text introduction to the topic that the tag represents. It is shown at the top of tag question lists, and as a tooltip wherever the tag appears. Complete this first! The full tag wiki is a detailed introduction to the topic, suitable as a destination for those curious about it: [...]  The phrase introduction to the topic screams definition to me. I don't even think that the phrasing is technically correct; it's not an introduction to the topic, it's an introduction to the tag. I would so much rather see a condensed version of the guidelines on the blog than what's currently on that sidebar. Yes, I realize that the sidebar eventually goes into more detail about what should be in the full wiki ("what questions should have this tag") but I think most people have stopped reading by then.  For instance, we just got the following 2 suggestions in rapid succession:  An oven is an appliance which produces heat in order to cook food. Coffee is a beverage which has a dark, acidic flavor and is prepared from the roasted seeds of the coffee plant.  Stack Overflow's excerpts are hardly much better:  PHP is a widely-used, general-purpose scripting language designed specifically for web development.  These aren't helpful to anyone - everybody on a cooking site knows what an oven is and what coffee is. Everybody on a programming site knows what PHP is. Worst of all, one of our experienced members approved these edits because, no doubt, the phrase "tag wiki" is horribly misleading and the "real" guidelines are buried in an off-site blog post.  I'm going to suggest the following alternative wording, but this is just an example - it would be great if someone with more talent at this could come up with something better:  What are Tag Wikis? The tag wiki excerpt explains which topics the tag represents. It is shown at the top of tag question lists, and as a tooltip wherever the tag appears. Complete this first! The full tag wiki provides detailed usage guidelines and useful references, suitable as a destination for those curious about it: ► what questions should have this tag? ► differences from other, similar tags ► which aspects are on/off-topic ► for highly-specialized tags, some basic definitions ► important links for learning more ► one reasonably sized page See .


$|f(z)|\leq 1$, then possible value of $(e^f)''(0)$

Let $f$ be an analytic function on $\bar{D}=\{z\in \mathbb{C}:|z|\leq1\}$. Assume that $|f(z)|\leq1~ \forall z\in \bar{D}$. Then, which of the following is NOT a possible value of $(e^f)''(0)$.   (i)6 (ii)2 (iii)$\frac{7}{9}e^{\frac{1}{9}}$ (iv)$\sqrt{2}+i\sqrt{2}$.  I calculated $(e^f)'=f'e^f$. Here if $(e^f)'(0)$ were $0$ then I could have used Schwarz Lemma to find the estimate. But here it is not $0$. Don't know how to proceed.


I've spotted two potential problems with the reputation tab, I hope both are documented on the image below:    First of all, there seems to be a off-by-one error. If september 24 is selected (in gray), The list underneath it shows +20 (which was, as the tooltip advices), the reputation of the day before. This behavior is spotted on all days. Perhaps it depends on the user's time zone. For me this is Central European Time (CET) (mentioning this for debugging purposes).  Furthermore as the image shows, removed posts are shown as well. This however results in the fact that the  is no longer taken into account. The total reputation for that day is 480, but this is partly realized with a post that was later removed. This is perhaps more a discussion on whether to take the reputation cap into account.


When reading a post in the app, the categories / tags are shown below the question and in the ListView as well. I would really like to be able to browse all questions with a specific tag (or a selection of tags, which seems to be a bit more difficult)   Are there any plans on implementing browsing by category / tag in the android app?


Safe to install Nautilus 3.6 in Ubuntu 12.04 LTS?

I tried installing the new nautilus via commands   sudo add-apt-repository ppa:gnome3-team/gnome3 sudo apt-get update sudo apt-get install nautilus   But the console warns me not to do that:  You are about to add the following PPA to your system:  Before upgrading your system to a new Ubuntu release (i.e. from Ubuntu 12.04 to 13.04), you should probably run ppa-purge ppa:gnome3-team/gnome3 first.  === Ubuntu 13.04 (Raring) === GNOME 3.8 that won't make it into the normal Ubuntu 13.04 repositories. Other parts of GNOME 3.8 are available in the https://launchpad.net/~gnome3-team/+archive/gnome3-staging PPA but beware that many of those components have known regressions from their GNOME 3.6 versions.  You need to run 'sudo apt-get dist-upgrade' to avoid problems. Please read the output before entering 'Y' to make sure important packages won't be removed.  === Ubuntu 12.10 (Quantal) === Parts of GNOME 3.6 that didn't make it into the normal Ubuntu 12.10 repositories.  === Ubuntu 12.04 (Precise) === Parts of GNOME 3.4 that didn't make it into the normal Ubuntu 12.04 repositories.  === Bugs === On Raring (13.04) please use 'ubuntu-bug' to report bugs against packages in this PPA  More info: https://launchpad.net/~gnome3-team/+archive/gnome3 Press [ENTER] to continue or ctrl-c to cancel adding it   So, is it safe to install Nautilus 3.6 on Ubuntu 12.04? Has anyone tried and did any problems appear?


Detailed, Understandable Explanation as to why 0!=1?

I have referred to many websites online regarding the proof, but I haven't understood it at all.. Please do help.  As far as I know, $n! = 1 \times 2 \times 3 \times 4 \times \dots \times n$  Then using the same logic, $0!=0$  Then why is it that $0!=1$ ?


When running Bibtex with a statement that has a comma at the end, this is obscuring real problems

When I run bibtex on document with a citation such as \cite{European00Presidency} and the .bib entry looks like this:  @MISC{European00Presidency,       author = {European Council,},   title = {Presidency conclusions},   year = {2000},   keywords = {Lisbon Strategy},   publisher = {European Council,},   type = {Government Document},   url = {http://www.consilium.europa.eu/uedocs/cms_data/docs/pressdata/en/ec/00100-r1.en0.htm} }   I get the very unhelpful warning message that " "European Council," has a comma at the end for entry European00Presidency" Which i really don't care about. But it hides other warnings such as entry not found or what ever. I would like to turn that warning off in Bibtex. Does anyone know how to do that.   I'm using MikTex 2.9, Jabref 2.9.2 and texmaker 4.1.1  As this is a problem for anyone dealing with large numbers of corporate authors I think there should be an option of changing this


Prove that for any two real numbers a and b $\big||a|-|b|\big|< |a-b|$

I know I should use the triangle inequality.


Listing all feature datasets and classes from multiple geodatabase into CSV file?

I have a folder having multiple geodatabase and I am calling that folder “Multiplegdb” There are 3 geodatabase in a folder which are as follows:   ABC.gdb UVW.gdb XYZ.gdb   Each geodatabase have several ‘Feature Dataset’ and each ‘Feature dataset’ have several ‘Feature Classes’.  My task:  I would like to list all the features datasets and feature classes in each geodatabase in a folder into CSV. I also would like to get the metadata information from each feature class into CSV file. The format of CSV file will be: GDB Name, Feature Dataset Name, Feature Classes name, Summary, Descriptions, Credits, Date Modified, File path.


Why Characteristic Impedance must be 50 ohms?

Where does this number come from?  For single ended it must be 50 ohm and for differential pairs 100 ohm. Why?  For PCB with controlled-impedance these are that common numbers. Outside of the PCB you can find others numbers for characteristic impedance. But what is the reason of use these numbers for the PCB tracks?


I've been using Ubuntu with Gnome Classic for a while and I've noticed recently that in the "Indicator Applet Complete" in the Top Panel, my name and the clock have disappeared.    I think it happened a while ago when I was messing around with packages. Every time I did apt-get... it would say "the following packages can be removed by apt-get autoremove", so I did it and then the clock and my name stopped appearing.   Can anyone help me? Thanks. It would be greatly appreciated.


Can't comment yet, but can't answer without the ability to clarify

I want to answer a question, but I need clarification from the author first. But I don't have enough reputation yet to comment, I can only answer. So how can I answer if I can't get clarification? Should I just move on to another question or am I missing something?


General infinite series convergence or divergence.

Suppose the infinite series $\sum a_n$ converges ($a_n \in \mathbb{R}$ not all positive or negative).  (1) Is it true that $\sum a_n^2$ converges?  (2) Is it true that $\sum a_n^3$ converges?  For (1), the answer is no. I found the counterexample $a_n = (-1)^n / \sqrt{n}$ which converges by alternating series, but $\sum a_n^2 = \sum1/n $ is divergent.  I'm unsure about proving truth of (2) and can't seem to find a counterexample.  Thanks for help.


Restrict the access to suggested edit reviews on deleted posts

on an answer deleted as rude/abusive is visible, even without logging in (and for users with less than 10k reputation). These users can't see the answer , via the , or a direct link to the .    This is a potential avenue for spammers, just like the suggested edit spam used to be, but is ; according to the :     In addition, in order to reduce the incentive for spammers to make spam edits that get rejected, suggested edit spam is hidden from logged-out users, so they can't show their clients public-facing pages with spam (so they won't get paid).   For this to work, the spammer would need two accounts, one to post the spam and a second one to suggest an edit. Even if the spam post is quickly nuked, the review link will be active forever. One could argue that logged-in users without 10k reputation shouldn't be able to see the suggested edits either; I'm partial to that.


How to create Wi-Fi hotspot in Ubuntu 12.04?

I am using Ubuntu 12.04 and I have an Ethernet internet connection.   I have connected this cable with my PC directly without using any wifi router. So I want to use my PC as wifi hotspot. Can you tell me how to create Hotspot in ubuntu 12.04?


Fit a probability distribution to a time series in R

Is it at all possible to fit a probability density function to a time series in R (with already existing functions)? I have a large set of time series describing frequencies of Google searches over 60 time points. What I want to do is fit several pdfs to every one of them in a loop with the fitdist() function from package fitdistrplus: Weibull, Inverse Weibull, Lognormal and possibly others.  Of course, this sequence data is ordered and this order gets lost when fitdist() makes a pdf out of the empirical distribution of the search frequency values (which of course then looks completely different than the distribution over time).   Is there a way to use fitdist() in a way that retains the time index? What I did up until now was just map the search frequencies at a time point to frequencies of that time point in a new variable (so: if there are 3 searches at time 2, the value 2 is represented 3 times in this new variable).  But the search frequency data is averaged, so I fear that I will introduce a great deal of bias by mapping to integer counts. Are there any other solutions for fitting time series data to a probability distribution?  P.S.: I know this question is similar to , but it is already a year old with no answers and I'm more concerned with how to do it in R specifically.


I have a variable $X$ which I am modelling with a mixture model: $$\begin{aligned} (X|A) &\sim \mathbb{1}_{0 \leq x < w \cdot m} \cdot \frac{\text{Gamma}(\alpha,0,\beta / m)}{k_1} \\ (X|B) &\sim \mathbb{1}_{x \geq w \cdot m - a} \cdot \frac{\text{Gamma}(\alpha,-a,\beta / m)}{k_2} \\ (X|C) &\sim \mathbb{1}_{- w\cdot (1-m) < x < 0} \cdot \frac{\text{NGamma}(\alpha,0,\beta/(1-m))}{k_3} \\ (X|D) &\sim \delta_a \end{aligned}$$ Where $\text{Gamma}(\alpha,\delta,\beta)$ is the gamma distribution (with pdf $\left(\Gamma(\alpha)\right)^{-1}\beta^\alpha (x-\delta)^{\alpha-1} e^{-(x-\delta)\beta}$), the $k_i$ are normalisation constants, $\text{NGamma}$ is a "negative gamma distribution", mirrored around the $y$ axis and with support in $(-\infty,0]$, $\delta_a$ is the degenerate distribution giving probability $1$ to the event $X=a$ and $0$ everywhere else, and $P(A)+P(B)+P(C)+P(D)=1$ so that all four cases are exhaustive.  I also have a variable $Y=\sum_i^N X_i$ where $\forall i:X_i \sim X$. I would like to find the distribution of $Y$.  I heard good things about finding the characteristic function of $X$ and then taking that to the $N^{th}$ degree and finding the distribution from there, but I do not know what the characteristic functions of the truncated gammas is. Does anyone have any pointers?


How am I supposed to install El Capitan on a new SSD without recovery partition?

My old mac's hdd died. It's dead. So I got a ssd and installed it in the macbook.  Now how do I get El Capitan on there? I find lots of tips online that speak of creating a bootable USB drive from the Capitan installer. But I can't download the El Capitan from the appstore because the mac has got nothing to boot from.  On my newer macbook running Catalina, I also cannot download El Capitan from the appstore because it doesn't show up when searching for it.  What I did download is El Capitan's InstallMacOSX.dmg via   But now I need to run/open this on the old mac with the fresh ssd.  I feel I'm stuck in a loop. I need a working OS to install an OS.....  Who can help me out here?


Installing AMD Radeon HD 7000M Series Graphics drivers on Ubuntu 19.04

Novice here  sudo lshw     Description: VGA compatible controller   Product  Thames [Radeon HD 7550M/7570M/7650M]   Manufacturer: Advanced Micro Devices, Inc. [AMD/ATI]    Physical ID: 0   Bus-Inormation: pci@0000:01:00.0   Version: 00   Width: 64 bits   Frequency: 33MHz   Abilities: pm pciexpress msi vga_controller bus_naster cap_list rom   (System language is German, please excuse possible translation errors)    System is Ubuntu 19.04 freshly installed, :~$ sudo apt install ubuntu-restricted-extras is also done.    So I know that 19.04 has driver support for Radeon HD 7xxxM series. Is there any document or instruction out there how to install that driver?


About the limit of the coefficient ratio for a power series over complex numbers

This is my first question in mathSE, hope that it is suitable here!  I'm currently self-studying complex analysis using the book by Stein & Shakarchi, and this is one of the exercises (p.67, Q14) that I have no idea where to start.     Suppose $f$ is holomorphic in an open set $\Omega$ that contains the closed unit disc, except for a pole at $z_0$ on the unit circle. Show that if $f$ has the power series expansion $\sum_{n=0}^\infty a_n z^n$ in the open unit disc, then      $\displaystyle \lim_{n \to \infty} \frac{a_n}{a_{n+1}} = z_0$.   If the limit is taking on $|\frac{a_n}{a_{n+1}}|$ and assume the limit exists, by the radius of convergence we know that the answer is $1$. But what can we say about the limit of the coefficient ratio, which is a pure complex number? I've tried to expand the limit directly by definition, with no luck. And I couldn't see how we can apply any of the standard theorems in complex analysis.  I hope to get some initial directions about how we can start thinking on the problem, rather than a full answer. Thank you for the help!


I have a problem that is occurring when I try to add multiple UV maps to one object. When I select a vertex group and unwrap, it works fine, unwrapping just that vertex group to a UV map. The problem is when I select another vertex group and make a new UV map then unwrap, it unwraps that vertex group, but in the UV editor it still shows the previous unwrap in that UV map. I know that it is not just showing up because of "keep mesh in sync" because when I select the previous UV map, the vertex group from the UV map made after that one does not show up in the previous one. It seems every time I make a new UV map, the UV map from before automatically shows up in the new one, regaurdless of using a different texture. I am also making sure that I have just the faces that I want selected when I unwrap. Any help would be greatly appreciated.


Claiming disk space after removing table field

I am running sql 2008 r2 and the db was working fine and fast for last 3 years untill about 3 months ago we added ntext field on very active and used table.  Now we are starting to get out of server space because of the huge expanding size of this table.  I read that shrinking ,we do not want to loose the indexing of db because it was working fast for years and we do not want to get fragmentation expending.  We decided to delete that field and all its values: Is there a way to delete the ntext field and all its values and release space without removing indexing ,without shrinking, without loosing db performance?  I am attaching the db size query output to show you size expanding of last 5 months.


I want to use mods in mincecraft but i dont know where to put the file or what to do with it once i have downloaded the mods... please help!


I need to select a specific layer in the layer tree before I run my python script. I have tried   with the code  registry = QgsProject.instance() layer = registry.mapLayersByName("name")[0]   but on the layer tree, there is no change of focus. The layer does not get selected. How can I accomplish that?


Possible Duplicate:          In a question, I see that each time I refresh the page, the answers were placed in a different order. The question has 3 answers each with zero votes. The users' reputation was something like 6, 1200, and 7300 but these numbers didn't affect the order.  What is the criteria of the sort order of the answers?


In Back to the Future, how did Marty get the timing right with the lightning strike?

So, in the first movie, presumably the Doc and Marty know exactly when the lightning will strike the clock tower. This is because Marty has the flyer with the picture of the stopped clock on it. In order to power the DeLorean, the Doc cooks up this contraption to conduct the lightning through a hook into the DeLorean. All Marty has to do is be driving at 88 mph and hit the wire at the exact right moment.  Here's the question though - if you recall, the Doc sets a timer and tells Marty to drive back to a pre-designated starting point. When the timer goes off, Marty is supposed to accelerate to 88 mph. My assumption is that the Doc has calculated the maximum acceleration of the DeLorean, and using this value has determined the exact starting point that the car needs to be at in order to hit the lightning at the right time.  Unfortunately, the car stalls. It takes Marty a while, but he's finally able to start it up. Being that he started late though...shouldn't he have missed the lighting?


Copy text from a list in an Outlook message without copying the list

How do I copy text from lists without extra invisible characters polluting my clipboard?  With the following text selection copied (not using double-click because it selects the trailing newline),    it pastes junk:    As a software developer, selection auto-expansion drives me nuts so it was one of the very first settings I tracked down to disable (along with ).    I tested the "Use Normal Style for bulletted or numbered lists" option  Is there another setting that controls this behavior?  Thanks.  P.S. Using Office 2013  P.P.S. The highlighted KB number does not exist in the  but I found it as an Windows event saying it configured an update. How is this possible? Perhaps an unannounced security hotfix?


Accidentally made 3D viewport take up entire screen

I hit a button, I'm not sure which one, and everything except the 3D view window disappeared completely. I assume they're just hidden, but outside of the HOTKEY I DON'T KNOW, there's no way to get the menus back and I'm kind of freaking out right now so please, if you know a fix, can you post it? There's NO menu bar, there's NO timeline, what you see in the screenshot is everything I can access outside of the tools and transform menus with the n and t hotkeys.


Why is the angular velocity $\omega$ always written in $rad/sec$? Is there anything wrong if I write it in $degrees/sec$? If no, then why almost all the books have it as $rad/sec$??


What is the sarcastic English word to describe a highly paid job?

What is the sarcastic English word to describe a highly paid job but with no responsibilities?


bike-frame-jig: customizations of a standard model - interesting features added

good day i am in the mid of creating a bike-frame-jig. the model is oriented at tanner w s jig:  see some the parts (here as Acronyms ) he is using: HT - Head Tube ST - Seat Tube TT - Top Tube DT - Down Tube BB - Bottom Bracket CS - Chain Stay SS - Seat Stay note: i found two or three very interesting "hacks" of Tanner W: see the following pictures: modifications made by Kristofer Henry a. HT Assembly - The standoffs sit 45 deg.    So here is the HT Assembly pretty much put together with the exception of the bottom "puck" holder and purge fittings. The standoffs sit 45 deg. back from the centerline of the extrusion. This allows me to have access to both sides of the HT/TT/DT area. I'll mount both standoff's on a rotary table and radius the ends to make my hands happy. Now that it is assembled, and I've had some time to stare at it long enough, I'm thinking I may change how the bottom standoff is mounted so it is fixed to the bottom of the extrusion and the whole assembly rotates off of it. Taking a measurement from the top of the main beam will enable an exact measurement to locate the bottom of the HT in space which will be nice..  and see the following discussion:  Francois Cau: What did you use for the pivot point of the extrusion part ? Is it just a simple screw ? (I'm trying to find a good/precise solutions for Rev2.0 of my jig...)  Kristofer Henry:  There is a shoulder bolt that rides on a pressed in bearing. It's pretty smooth and clamping action is good.  queston: - very very interesting .- Why did you change the standoff - with a 45 degree-skip?! Can you compare it with a standard - standoff another hack: by kolb-Rahmenbau.ch  he uses a very very big plate - see the right side  of the spine ...: the plate for the head tube assembly is very very big - much bigger than that one that Tanner W uses. i guess that this is much more precicely .. he can work with a lower degree of measurement-failures how do you see this !? what do you think !? What else do you like at this bike-frame-jig !? I think it is very very interesting - if we compare it with tanner ws jig!? look forward to hear form you


Old User page developing rendering errors

On the old style user pages such as mathoverflow I noticed that the long comment on the right is floating lower today than it did previously (as recently as yesterday). I don't know if we care, but I noticed it.


Implied string comparison, 0=='', but 1=='1'

I was debugging something and discovered some strangeness in JavaScript:  alert(1=='') ==> false alert(0=='') ==> true alert(-1=='') ==> false   It would make sense that an implied string comparison that 0 should = '0'. This is true for all non-zero values, but why not for zero?


So I'm having an odd problem, I've spent a decent chink of today making a hollow knight charm in 3D and the way I made it involved making a lot of separate objects and a lot of the time I end up hiding certain objects and for whatever reason, they aren't un-hiding.  You can see in the outliner that they still exist and in the properties menu that they are still there and have dimensions and whatnot, but they don't respond to alt + H nor do they respond to the same command via the object menu. I have no idea what happened here but that was alot of work that id rather not have lost so if anyone has any clue please respond asap.


User  has posted several answers, all of which are on-topic but are essentially advertisements for software his company has for sale. They are also formatted like an email instead of an answer. For example:     Alexey, one solution you should consider is a horizontal scalability   solution that will take care of all of these problems for you. Full   disclosure: I'm founder & CTO of a company called ParElastic and we   offer a product that provides horizontal scalability with MySQL and we   fully support the kind of multi-tenancy you support. Please check us   out at www.parelastic.com. You can read about our testing and   performance characteristics on our website and we've shared some   benchmark information as well.      Thanks,      -amrith   When I encountered the  (now 10k only) in the first posts queue, I edited the post, and tried to make it seem less promotional. The user does mention that founded the company, but now after seeing that all of his answers are self-promotion like this, I'm wondering if I should have flagged as spam instead.  The other key point is that the user answered a question where the OP specifically asked for a free/open source solution.  Should questions like these be flagged as spam, or just edited?  UPDATE: It looks like his answers have already been deleted, so maybe the solution is to flag as spam, but I'd still like clarification on this.


Currently we capture fanatic, voting ring or rage-type activities, by measuring the number of up-votes or down-votes between the same two users in a certain (relatively short) time period. When this is detected by the system, the votes are reversed, and I've never bothered to investigate what else happens after that - though I'm sure some form of wrist-slapping ensues.  While it is intended to be well-guarded for obvious reasons, the algorithm used is not exactly a secret, and I am sure there are plenty of examples where people are dangling (maybe intentionally, or maybe by dumb luck) just on the safe side of getting caught.  Personally I believe there are active, intentional, long-term vendettas in operation right now where users either:   blindly up-vote every answer from a user; or, down-vote a particular user once or twice a day, regardless of topic or quality.   Now, maybe the first one is valid - if I'm operating in the same tag-sphere as some smart person, it may just be that I'm constantly enthralled with their answers, and I'm not even noticing who they're written by. (Though, even Skeet isn't perfect, and I haven't up-voted every answer I've seen him post.)  But still, can we do a better job of catching - or at least noticing - this activity over the long term in addition to the short term?  The behavior is the same, and shouldn't be tolerated, regardless of the time frame - vengeful rage serial voting, blind staker crush serial voting, and painstakingly patient serial voting are all undesirable behaviors IMHO.  I'm not saying it has to do anything automatically, as I'm well aware of the possibility of false positives. And I'm not even sure what to propose as a time frame or a vote threshold.      But if a large percentage of my up-votes or down-votes are against a particular user, and especially if on a majority of those posts I am the only one voting in that direction, I think it should at least be raised as some kind of flag to moderators.   This would work much like how other suspicious activity is highlighted (but also not dealt with automatically). If a pattern becomes obvious and persists, then they can intervene in some way (or not, but at least they were provided with the information - just like they can reject and ignore manual flags). Today, all I can do is e-mail team@stackoverflow.com, and unless I know exactly which person(s) are involved, there is not much they can do about it.  And you're thinking, "Meh, let some hater down-vote you once or twice a day. Unless all you're posting is utter crap, it should be statistically insignificant." You're right. But reputation is not the point, and is not the motivation behind my request. What I'd like to see curtailed is the tendency for folks to down-vote a question or answer because of who posted it, not because of what it said or didn't say. When a down-vote is personal it can leave a person second-guessing the quality of their post. Which isn't necessarily a bad thing, except when it happens repeatedly.  Sorry for the essay but I wanted to try to anticipate and cover all the objections and hole-poking.


Visit UK like a tourist with C-Visit-business

I am confused a little I want to attend a UK like a tourist but my visa type is C-Visit-Business. I read a lot of information but can't understand can I go to UK or can't.


$f\in A[x]$ is a zero divisor if and only if there is $a\neq 0\in A$ with $a\cdot f=0$  One direction is trivial. The other direction I find the hint confusing. It says we should choose a zerodivisor $g$ of $f$ with a minimal degree. We write $f=\sum^n a_ix^i$ and $g=\sum^m b_j x^j$. Then all the coefficients of $fg$ are zero. In particular the highest degree coeeficent is zero, $a_nb_m=0$. By assumption then $a_ng$ must be zero since it has a degree less than $g$ and it annihilates $g$. Then the hint says to use induction on $a_{n-r}$. Are we inducting on $r$? It is also not clear to me how to result follows from this? This question is not a duplicate of  as I am specifically asking how to use the hint and do this problem with the induction.


What is the correct way to provide a string on the command line?

I'm creating a program to find the standard deviation of an ArrayList of double values given by the user. I am to provide a string on the command line to indicate whether I want the mean (mean), or the standard deviation (std). However, I am having difficulty giving those strings to the command line.      This is the error I'm getting:  > Exception in thread "main" java.lang.NumberFormatException: For input string: "std"         at java.base/java.lang.NumberFormatException.forInputString(Unknown Source)         at java.base/java.lang.Integer.parseInt(Unknown Source)         at java.base/java.lang.Integer.parseInt(Unknown Source)         at StatDriver.main(StatDriver.java:28)          public static void main(String[] args) {            Scanner input;           ArrayList<Double> data;           int dataSize;           String userInput = "";            // Determine the appropriate array size.           if (args.length > 0) {              dataSize = Integer.parseInt(args[0]);           } else {              dataSize = 15;           }            // Create the array.           data = new ArrayList<Double>(dataSize);            // Read values from the terminal.           input = new Scanner(System.in);           while (input.hasNextDouble()) {              data.add(input.nextDouble());           }            // Calculate and display the results.           if(args[0] == "mean") {               System.out.printf("Mean: %.2f\n", Stats.mean(data));           }           else if (args[0] == "std") {               System.out.printf("StdDev: %.2f\n", Stats.stdDev(data));           }           else {               System.out.printf("Mean: %.2f\n", Stats.mean(data));                }        }     }


Proving this integral to be 0 in complex analysis

This particular question was asked in my  complex analysis assignment which couldn't be discussed due to pandemic.  prove that $\int_{0}^{2\pi} \log|1-e^{i\theta}|d{\theta} = 0$ .  Unfortunately, I have no idea on which theorem should be used to prove this result and I cannot ask anyone in my class as none of my friends did the assignment . Kindly help me!


errors while compiling the following codes

In the connection of my previous question.     Codes:  \documentclass[12pt, a4paper]{article} \usepackage[a4paper,top=1 in,bottom=1 in,left=0.7 in,right=0.7 in]{geometry} \usepackage[utf8]{inputenc} \usepackage[misc]{ifsym} \usepackage{amsmath} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{graphicx} \usepackage{tikz} \usepackage{pst-tree} \psset{levelsep=1,treesep=1,nodesep=2pt} \usepackage{fancyhdr} \pagestyle{fancy} \usepackage{lastpage} \lhead{} \rhead{} \chead{} \rfoot{Page \thepage \hspace{1pt} of \pageref{LastPage}} \lfoot{} \cfoot{} \renewcommand{\headrulewidth}{0.4pt} \renewcommand{\footrulewidth}{0.4pt} \begin{document}     \psTree{\TR{36}} \Tcircle{2} \psTree{\TR{18}} \Tcircle{2} \psTree{\TR{9}} \Tcircle{3} \Tcircle{3} \endpsTree \endpsTree \endpsTree \end{document}   Errors:  line 49: Undefined control sequence. \Tcircle{2} line 49: Undefined control sequence. \Tcircle{2} line 49: Undefined control sequence. \Tcircle{2} line 49: Undefined control sequence. \Tcircle{2} line 50: Undefined control sequence. line 50: Undefined control sequence. line 50: Undefined control sequence. line 50: Undefined control sequence. line 51: Undefined control sequence. \psTree{\TR{18}} line 51: Undefined control sequence. \psTree{\TR{18}} line 51: Undefined control sequence. \psTree{\TR{18}} line 51: Undefined control sequence. \psTree{\TR{18}} line 53: Undefined control sequence. \Tcircle{2} line 53: Undefined control sequence. \Tcircle{2} line 53: Undefined control sequence. \Tcircle{2} line 53: Undefined control sequence. \Tcircle{2} line 54: Undefined control sequence. line 54: Undefined control sequence. line 54: Undefined control sequence. line 54: Undefined control sequence. line 55: Undefined control sequence. \psTree{\TR{9}} line 55: Undefined control sequence. \psTree{\TR{9}} line 55: Undefined control sequence. \psTree{\TR{9}} line 55: Undefined control sequence. \psTree{\TR{9}} line 57: Undefined control sequence. \Tcircle{3} line 57: Undefined control sequence. \Tcircle{3} line 57: Undefined control sequence. \Tcircle{3} line 57: Undefined control sequence. \Tcircle{3} line 58: Undefined control sequence. line 58: Undefined control sequence. line 58: Undefined control sequence. line 58: Undefined control sequence. line 59: Undefined control sequence. \Tcircle{3} line 59: Undefined control sequence. \Tcircle{3} line 59: Undefined control sequence. \Tcircle{3} line 59: Undefined control sequence. \Tcircle{3} line 60: Undefined control sequence. line 60: Undefined control sequence. line 60: Undefined control sequence. line 60: Undefined control sequence. : You have requested release `2014/05/01' of LaTeX, but only release `2011/06/27' is available.


What is this notification icon that looks like a raindrop?

My friend bought a Sony Xperia Z3, and started to install all the apps she liked. After installing dozens of apps, she realized that there is a notification icon looks like a raindrop. I was asked to get rid of it, but I couldn’t. I tried to stop all the running apps, but it remained on top. If she pulls down the notification bar, it shows nothing.   Any idea what this could be?status


Is the camera sensor or the lens the limit to resolution?

I have a pretty high res sensor on my camera, but sometimes I have the feeling my lens doesn't even get to this resolution. How can I tell if my camera sensor has not enough resolution or if the lens is the limit?  For example I have a 5DMarkII with 22 Megapixel Sensor. And a Canon 35mm 1:2 Lens. (For example aperture at 11 shutter at 1/2000)  How can I visually see whether the bottleneck is the lens or the cameras resolution? Is there any place were I can look up the optical resolution of a lens?


What is the relationship between $\text{Cov}[\mathbf{X},\mathbf{X}]$ and $(\mathbf{X}^T \mathbf{X})^{-1}$ in multiple regression?

The matrix formulation of multiple regression for $n$ observations is $$ \mathbf{Y} = \mathbf{X}^T \beta + \varepsilon, $$ where the error $\varepsilon$ has finite variance $\sigma^2$. Let $\mathbf{b}$ be the estimated coefficients found when we solve the multiple regression problem with least squares. In Theorem 4.3 of the book Econometric Analysis by William H. Greene it says that asymptotically $\mathbf{b}$ is distributed as $$ \mathbf{b} = \mathcal{N}\bigg(\beta,\frac{\sigma^2}{n}Q^{-1}\bigg), $$ where $Q$ is defined in equation 4.19 as \begin{align*} Q := \text{plim}_{n \to \infty} \frac{\mathbf{X}^T \mathbf{X}}{n}. \end{align*} which is a positive definite matrix. Suppose we write the covariance matrix of $\mathbf{X}$ as $$ \text{Cov}[\mathbf{X},\mathbf{X}] =  \begin{bmatrix} \sigma_{X_1 X_1} & \sigma_{X_1 X_2} & \dots \\ \sigma_{X_2 X_1} & \sigma_{X_2 X_2} & \dots \\ \vdots & & \ddots \\ \sigma_{X_n X_1} & \dots & \dots & \sigma_{X_n X_n} \end{bmatrix}, $$ where $$ \sigma_{X_i X_j} =  E[(X_i-E[X_i])(X_j-E[X_j])], $$ I want to know how the matrix $(\mathbf{X}^T \mathbf{X})^{-1}$ relates to the covariance matrix $\text{Cov}[\mathbf{X},\mathbf{X}]$. For example, if we modify the elements of $\mathbf{X}$ to make them more collinear, the off-diagonal elements of $\text{Cov}[\mathbf{X},\mathbf{X}]$ will increase in magnitude and $(\mathbf{X}^T \mathbf{X})^{-1}$ will become 'harder' to invert. But I am looking for a precise mathematical expression that relates the two matrices. Can $(\mathbf{X}^T \mathbf{X})^{-1}$ be expressed in terms of $\text{Cov}[\mathbf{X},\mathbf{X}]$ somehow? E.g., can the elements of $(\mathbf{X}^T \mathbf{X})^{-1}$ be written in terms of the elements of $\text{Cov}[\mathbf{X},\mathbf{X}]$?


I have tried to use induction, but after I assume that P(n) is true, I can't go further to prove that P(n+1) is true as well. I also have tried to find an intermediate inequality, but I can't figure out which inequality I should start from. Something that seemed to be useful was taking P(n) and multiplying it by $(1+\frac{1}{(n+1)^3})$, therefore I have come to this $(1+ \frac{1}{1^3})(1+\frac{1}{2^3})...(1+\frac{1}{n^3})<3 | \times(1+\frac{1}{(n+1)^3})$ $(1+ \frac{1}{1^3})(1+\frac{1}{2^3})...(1+\frac{1}{n^3})(1+\frac{1}{(n+1)^3})<3(1+\frac{1}{(n+1)^3})$ but, as anyone could imagine, I came to contradiction because I've tried to prove that $3(1+\frac{1}{(n+1)^3})<3$ which is false. Any help it would be useful.


Is it just me or does sending explorers only cost 100 catpower in the latest build? Or is this because they didn't actually find anyone?


Using time manager for shapefile with different timestamps

I have a network which contains speed information for each segment at different timestamps. I would like to create an animation of speed changes during the day. There is multiple columns which contain speed for a segment at a given time. How do I work around the fact that time manager plugin only reads time value from one column ?


I learned "remember to" means "don't forget to" but it is only used in future or present things. For example, "I will remember to mail these letters." means "I will not forget to mail these letters.)  But when they become past tense, I hear that "I remembered to mail these letters." doesn't mean "I didn't forget to mail these letters". Is this right?  Does "I remembered to mail these letters." mean "I remembered that I mailed these letters" or other? Could you teach me?  I know the difference between "remember to" and "remember ～ing". I asked the difference between "remember to " and "remembered to" because I hear the meaning change beside it become past.


If I have a String containing for example "234" and I want to print it out as "£2.34" How do I do this in Java?

Also if I have:  "23" and I want to print that out as 23p  How can I get Java to see if the string has 2 digits that are less than 99(p) or, "234" and see that there are more than 2 digits and convert the "234" to "£2.34"  Thanks


How to configure Chrome to open magnet URI's with Deluge?

After upgrading to Ubuntu 11.04 (natty) from 10.10, I can no longer open magnet (torrent) links in Chromium, and set deluge to automatically open and accept the URL. (Edit: currently ".torrent" files are not a problem, but , e.g. of the form "magnet:?xt=urn:...", are now the only problem. Not sure if something updated...?) Rather, now only transmission will automatically open torrents, magnet links, etc. There doesn't seem to be a way to set deluge to be the default torrent client. (And, there also doesn't seem to be a "default application" setting for BitTorrent client to replace transmission w/ deluge.) Notes:  I found some old threads on this issue, and only a  or  newer ones. The newer threads seem to suggest xdg-open is to blame. But not many people seem to be running into this problem, so... maybe it's just me? Not using Firefox, so manually setting apps for mime-types or extensions doesn't work (that's not an option in chrome/chromium, AFAIK -- you have to rely on the OS) I uninstalled transmission, and then basically nothing happened when clicking on torrent/magnet links. running from the shell also opens transmission (not deluge): xdg-open "magnet:?xt=urn:bt..&tr=http://tracker.....com/announce".  My current URL handlers are: $ gconftool -a /desktop/gnome/url-handlers/magnet command = deluge "%s" needs_terminal = false enabled = true  The only work-around I have (which does work) is to rename /usr/bin/transmission-gtk{,.bak} and create my own /usr/bin/transmission-gtk: $ cat /usr/bin/transmission-gtk #!/bin/bash deluge "$@"  Anyone else run into this, know of a bug, workaround, or...?