I have two boxes, one with ten balls, eight white and two black and the other with ten balls, four white and six black. Without seeing I choose a box and choose three balls from this.  What is the probability that the fourth ball I'll choose is black if the other three are not all white?    My question is: Can I find the probability that the fourth ball is black if the other three balls are all white and then count $ 1- $ this probability?   I solved my question. For the exercise, that's my trying:   $E$ = the fourth ball is black  $A$ = the three balls are ALL WHITE  Then $P(E) - P(E|A)$ will give me what I need.  For $P(E)$:  $C$ = I choose first box and $D$ = I choose second box  $P(E) = P(E|C) \cdot P(C) + P(E|D) \cdot P(D)$  I will find $P(E|C), P(E|D)$ from the right groups of four balls  So, if $a$ is a white ball and $b$ is a black ball then:  For the first box: $aaab, baab, abab, aabb$ I sum the possibilities for all these groups and I get $P(E|C)$.  For the second box:  $aaab, baab, abab. aabb, bbab, babb, abbb, bbbb$ I sum the possibilities for all these groups and I get $P(E|D)$.


I am generating a pdf with pandoc (source is markdown) and as latex formatting is want to do, the images sometimes go onto the next page and not exactly where they are inside the content.    This is okay, but my latest version of a document has an image which is intersecting a code block.  code here   IMAGE + image tile  code continues   For obvious reasons this is jarring and not what I expected to happen.  Is there a way to fix this?  I do not want to inline the image (everything about how the image is displayed is how I want it, except its location).  Thanks!


Direction of cross product of two vectors

Are there several ways to find the direction of a×b other than right hand thumb rule?


operator* overloading for matrix times scalar not working

I would like to mulitply a matrix with 3 elements (like a vector from physics) double3 with a scalar value. I wrote a class for everything (as you can see below). The problem is, that the overloaded operator* is not recognized. I can't find any issues with the syntax and also tried to adding const and & accordingly, to make sure the operator accept rvalues too. Error   C2676   binary '*': 'double3' does not define this operator or a conversion to a type acceptable to the predefined operator  Can anyone tell me where the issue is in the following code is? // main #include "vec3.h"  int main() {     double3 result, result2;     double3 vec = { 1,2,3 };     double testd = 2.3;     result = vec * testd;     result2 = vec * (testd / 5.0); }  // vec3.h #pragma once #include <iostream>  template <typename T> struct vec3 {     // assign data     vec3(const T u, const T v, const T w) : d{ u,v,w } {}     vec3(const T a[3]) : d{ a[0],a[1],a[2] } {}     vec3() : d{ 0,0,0 } {}          // read (and write) data     T& operator[] (int i) { return d[i]; }     T operator() (int i) const { return d[i]; }      // vec3.cpp contains more mathematical operations  protected:     T d[3]; };  using double3 = vec3<double>; using int3 = vec3<int>;  // vec3.cpp #include "vec3.h"  // vec3-scalar operations template<typename T>    // scalar multiplication vec3<T> operator*(const vec3<T>& a, T s) {     return vec3<T>(a(0) * s, a(1) * s, a(2) * s); } template<typename T>    // scalar multiplication 2 vec3<T> operator*(T s, const vec3<T> &a) {     return vec3<T>(a(0) * s, a(1) * s, a(2) * s); }


In the U.S., we seemingly prefer the former to the latter. However, I was sitting with my friends when one of them stated that he was "disorientated" while we were playing a video game.  My theory, at the time, was that he made the language connection between a "youtube game commentator" and "disoriented", resulting in a mash-up of the two words. Due to the rise of usage in the word "commentator", at least in the U.S., it made plenty of sense.  However, I just did some look-up this morning, out of curiosity, and it seems that the British prefer the latter to the former. It seemed a bit odd to me, so I asked some acquaintances in an , and an interesting proposal was made.  Perhaps "Disoriented" is more of an adjective, where "Disorientated" is more appropriately a verb.  An example would be:   Adjective: He became disoriented in the forest.  Verb: He disorientated himself in the forest.   Thoughts?


I have figured out a way to show that     $$e=\sum_{i=0}^\infty {1\over i!}$$   I am wanting to formally show that     $$e^x = \sum_{i=0}^\infty {x^i\over i!}$$   I have been looking at power series/Taylor series for a long period of time (absolute convergence) and have seen multiple proofs that I look past because something seems illegitimate with radius of convergence. If someone explains the general proof behind Taylor series/power series absolutely converging so there is no gray area, that would work as well. I will probably ask some questions in the comment area if this is the case. There must be something I am missing.


Template singleton class functions linker error

I am trying to implement a Utilities singleton class, which includes a helper function to format std::string's. The code is from this link here,  however I get a linker error somehow. (I modified const std::string& format to be a const char* format for performance, but both don't work). Here is the header file: utilities.h #pragma once  #ifndef UTILITIES_H #define UTILITIES_H   #include <string>   class Utilities { public:     Utilities(const Utilities&) = delete;     Utilities(Utilities&&) = delete;     Utilities& operator=(const Utilities&) = delete;     Utilities& operator=(Utilities&&) = delete;      template<typename ... Args>     static std::string FormatString(const char* format, Args ... args);  private:     Utilities();      static Utilities& Get_Instance(); };  #endif // !UTILITIES_H  and utilities.cpp #include "utilities.h"  #include <memory> #include <string> #include <stdexcept>  Utilities::Utilities() {  }  Utilities& Utilities::Get_Instance() {     static Utilities instance;     return instance; }   template<typename ... Args> std::string Utilities::FormatString(const char* format, Args ... args ) {     int size_s = std::snprintf(nullptr, 0, format, args ...) + 1; // Extra space for '\0'     if (size_s <= 0) { throw std::runtime_error("Error during formatting."); }     auto size = static_cast<size_t>(size_s);     auto buf = std::make_unique<char[]>(size);     std::snprintf(buf.get(), size, format, args ...);     return std::string(buf.get(), buf.get() + size - 1); // We don't want the '\0' inside }  The linker error is: Severity    Code    Description Project File    Line    Suppression State Error   LNK2001 unresolved external symbol "public: static class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > __cdecl Utilities::FormatString<double>(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &,double)" (??$FormatString@N@Utilities@@SA?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@ABV12@N@Z)  file.obj    1


How to convert Datetime into only Date format

lblAppointmentDate.Text = dt.Rows[0]["AppDate"].ToString();   This is my code giving the output as:     AppointmentDate: 11/19/2014 12:00:00 AM.   I want only Date as 19/11/2014.


ssh: connect to host port 22: Connection timed out when hostname used

I have two Ubuntu 18.04 and 20.x installs at home and trying to ssh between them, I can connect by Internal IP but not by hostname Setup: Machine A: 192.x.x.115 Machine B: 192.x.x.125 both installs have ssh running and I can connect fine using internal IP. From Machine B I would like to connect to Machine A using hostname  or hostname.ddns.net Here are things I have setup: Machine A: machineA> /etc/hosts 127.0.0.1    machineA.ddns.net machineA  192.x.x.115  machineA  machineA> /etc/hostname machineA.ddns.net  machineA> /etc/resolv.conf nameserver 127.0.0.53 options edns0 trust-ad search hsd1.xx.isp.net  Machine B: machineB> ssh user@192.x.x.115  # i.e machineA is successful machineB> ssh -vvv user@machineA.ddns.net gives Connecting to machineA.ddns.net [ISP assigned address] port 22.  ssh: connect to host machineA.ddns.net port 22: Connection timed out  machineB> ssh -vvv user@machineA ssh: Could not resolve hostname machineA: Name or service not known  SSH_from_external_to_machineA is successful ssh user@machineA.ddns.net  # is successful commands tried on machineA: machineA> sudo service ssh status   # gives active(running) machineA> sudo netstat -alnp | grep :22  # shows :22 with LISTEN machineA> sudo iptables -A INPUT -p tcp --dport ssh -j ACCEPT  I feel ISP is not blocking ssh from ssh since I can connect from external using machineA.ddns.net  Router is allowing port 22 since I can connect using IP.   I feel hostname is not resolved correctly, please review and let me know if I am missing any additional steps. Thanks, Additional edits: machineB> ping machineA_Hostname   is successful machineB> nslookup machineA.ddns.net is showing external IP as expected machineB> ssh machineA   # Could not resolve hostname: Name or service not known machineB> ssh machineA.ddns.net attempts to connect to exact external IP that was reported by ping and 'Connection timed out'


map and list value ambiguity on insertion : java

i am working with list insertion in map and not able to understand the insertion behaviour.  public class TestList {  public static void main(String[] args) {      String strarray[] = new String[5];      for(int i = 0; i < 5; i++ ){          strarray[i] = "Demo" + i;     }      Map<Integer, List<String>> cluesByText = new HashMap<Integer, List<String>>();     int j = 0;     for (String str : strarray) {          System.out.println(str);         List<String> s = cluesByText.get(str);         if (s == null) {             s = new LinkedList<String>();             cluesByText.put(j, s);         }          s.add(str);         s.add(str);         s.add(str);         s.remove(1);         // why it is storing without doing cluesByText.put(j,s);         j++;     }      //output is:      System.out.println(cluesByText);  } }   Problem  is  while doing  insertion  of list  into the map and then on changing the contents of list by insert/delete operation , it is getting reflected in the list which was stored in map in previous line.  final output coming on printing map contents is.  {0=[Demo0, Demo0], 1=[Demo1, Demo1], 2=[Demo2, Demo2], 3=[Demo3, Demo3], 4=[Demo4, Demo4]}   i am not able to understand why it happening in this way as  state of list is already been stored in map?


How to make a Photoshop droplet export PNG into the folder where source PSD is located in

I am looking for a way a Photoshop droplet could export PNG from a PSD file into the folder of that PSD file. I plan to create a droplet I could drop PSD files in and the droplet would 'convert' those PSD into PNG and save those PNG in the folders where the PSD are located in. Thank you in advance!


This is the opposite of . Instead of asking why Time-Turners weren't used to destroy Voldemort, I want to know ...  Why didn't Voldemort try to get a Time-Turner?  He and his Death Eaters could have gotten one from the  in many ways, (e.g. - Confundus, Imperius Curse, Polyjuice Potion, etc...) but they didn't. They clearly infiltrated the Ministry of Magic's Department of Mysteries to attack Harry. Why would Voldemort bother setting up an elaborate plan to get Harry to get a prophecy when you can sidestep all of that, grab a , and make a timeline where he takes over the world?   provides an insightful out-of-universe explanation, but I prefer an in-universe explanation.


Why don't the black holes appear black in color in images of galaxies taken from HST?

According to NASA      a black hole is anything but empty space. Rather, it is a great amount of matter packed into a very small area   According to the documentary  about Black Holes     Gravity here is so strong even light cannot escape   Which leads me to believe that Black Holes basically are masses so compact but great which gives them very strong gravitational influence (Newton's Gravitational Law) that light is not allowed to go out of, hence a "Black" hole.  If my above understanding of Black Holes is correct, then why is those Spiral Galaxies pictured using Hubble Telescope is showing a big shiny ball instead of a "Black" hole ? What is the obvious clue that I am missing here ?  Here is the image of Andromeda Galaxy image taken using Hubble.


Linear algebra, construction of counter example for two rectangular matrices such that $AB=I$ but $BA\neq I$

We have a matrix $A$ of order $m$ by $n$ and a matrix $B$ of order $n$ by $m$ where entries are from real numbers. We are given that $AB =I$ and we need to check whether $BA =I$ or not. If we have square matrices then it is true but here are rectangular matrices. I know that it doesn't hold true for rectangular matrices and I am trying hard to find some counter example but unable to find such matrix. I want to learn about how to construct  matrices as counter examples in linear algebra as in this case. Thanks


How do I get an application to appear as a choice in update-alternatives?

I separately installed the Firefox Beta and Alpha channels, and have desktop configuration files pointing to them in ~/.local/share/applications. However, stable Firefox is being used as my default browser by the system. (Firefox Beta used to be used until I messed with the "Default Applications" in System Settings, where it is not listed.)  I tried running sudo update-alternatives --config x-www-browser to manually change it, but it's only recognizing Chromium and Firefox (stable) and showing them as a choice.  What can I do to get custom desktop configuration files in ~/.local/share/applications to be seen as default alternatives? I think I may have to fiddle with the desktop config files, or with mimeinfo.cache or mimeapps.list?  Running Oneiric.  Here is the content of the firefox-beta.desktop file I created:  [Desktop Entry] Name=Firefox Beta Exec=firefox-beta -P Beta -no-remote Icon=firefox Terminal=false X-MultipleArgs=false Type=Application StartupNotify=true StartupWMClass=Firefox Categories=GNOME;GTK;Network;WebBrowser; Comment[en_US]=Firefox Beta Channel MimeType=text/html;text/xml;application/xhtml+xml;application/xml;application/vnd.mozilla.xul+xml;application/rss+xml;application/rdf+xml;image/gif;image/jpeg;image/png;x-scheme-handler/http;x-scheme-handler/https;x-scheme-handler/ftp;x-scheme-handler/chrome;video/webm; Name[en_US]=Firefox Beta  [NewWindow Shortcut Group] Name=Open a New Window Exec=firefox-beta -new-window about:blank TargetEnvironment=Unity


Grant permanent UAC permission to one program?

Possible Duplicate:          Is there a way to grant permanent UAC permission in Windows 7 to a single program?  I have an old program that's supposed to start up in the background when Windows starts.  I want to have it "just work" without the nagging, but keep UAC in all other cases.


What is the difference between Nullable and bool?

When I reverse engineer my classes I get the following:  public Nullable<bool> Correct  { get; set; } public Nullable<bool> Response { get; set; }   I coded:  public bool? Correct  { get; set; } public bool? Response { get; set; }   Can someone tell me if there is any difference between these two. I have not seen the Nullable<bool> before and I'm not sure why it does not just create a "bool".  Note: I changed my coded to bool? in response to comments by Jon


Unable to log into Pokemon Go on mobile data but can on wifi

This is only since the new update 0.37.0  I have been playing since the game came out in the UK and have got a Moto G phone  I log on using google accounts. I dont really want to start again as I have 104 different pokemon.   I can play fine on wifi, but can not connect on my mobile data. I have uninstalled the app and then reinstalled it, it didn't work, I logged in and out a few times to test it, and then I restarted my phone and the same thing again, the bar loads 1 bar and then comes up saying sign out.


How to get the Dock to open the Documents and Download folder in Finder?

When I click on the Documents or Downloads folder in the Dock, a Grid comes up.  Is there a way to get it to just open in the Finder?  Instead of having to click on Documents and then click on Open in Finder.


How do I filter messages that are sent to a single recipient?

I am receiving emails that has been copied to a several email addresses. For example, an email is copied to engineering.myorg@gmail.com and marketing.myorg@gmail.com and I have subscribed to these two email groups; hence I am getting these emails. And there are some other emails those are only sent to marketing.myorg@gmail.com.   Let's say that I have created two filters, and some email belong to both of these groups. I need to filter the emails that exclusively are sent to marketing.myorg@gmail.com to delete those at once.  How can I do this?  Note: The actual mail groups are in format of mail-group@myorg.com; because, our organization is using gmail application for email.


Comparison of log-likelihood of two non-nested models

I know I can only use the log-likelihoods of two models as selection criterion if they are nested. However, I don't understand this completely. Why isn't it possible to apply this reasoning to non-nested models? I think the higher the log-likelihood the better fits the model the data. I am also aware of other criteria as AIC but this doesn't helps me to understand the issue with the log-likelihoods.


Calculate required toroidal core size(Cross section area) for transformer

How to calculate required toroidal core size(Cross section area) for 200VA transformer.is that any formula or method to select core.I mean to say suppose I won't make 200VA toroidal transformer so how to select required core size OD, ID, Height of toroidal core.


Is there away to sort the tags on SO by the amount of followers they have? Currently the tags are sorted by the "liveliness" of the tag, and not by the amount of SOers interested in the tag. I think it is an good feature that will allow more important tags to come up for new users.


Difficulty spanning a row to full height

I have made a columnar layout that works fairly well for my needs, but I am experiencing an issue with the height of one column. I have prepared a jsBin that demonstrates the problem;    Basically, when you scroll down - eventually you start seeing white on the left side. Is there any way to force this to stretch all the way down indefinitely?  This is not using a flex-box layout. It is simply achieved using :before, and :after pseudo-selectors.


JavaFX8: TableView row added changes all previous rows to same values?

I’m using JavaFX 8 and JDK 1.8.0_77 in IntelliJ with SceneBuilder.  I created the Message Center GUI with SceneBuilder.  I have a TableView with five columns, Start Date, End Date, Message, Category and Status.  The values are entered via controls and saved in the Message Object when the Add button is clicked.  The Message object is added to the msgTableView with msgTableView.getItems().add(message).    The problem is as I add a message object to the bottom row, all the previous rows change to the last row; the number of rows is correct but all the rows are the same.  My Message object code:  public class Message implements Serializable {   public static LocalDate startDate = LocalDate.now(); public static LocalDate endDate = LocalDate.now(); public static String newMsg; public static String status; public static String category;  public void Messages(LocalDate StartDate, LocalDate EndDate, String NewMsg, String Status, String Category){     this.startDate = StartDate;     this.endDate = EndDate;     this.newMsg = NewMsg;     this.status = Status;     this.category = Category; }  // --------------Getters and Setters----------------------------  public LocalDate getStartDate() {     return startDate; }  public void setStartDate(LocalDate startDate) {     this.startDate = startDate; }  public LocalDate getEndDate() {     return endDate; }  public void setEndDate(LocalDate endDate) {     this.endDate = endDate; }  public String getNewMsg() {     return newMsg; }  public void setNewMsg(String newMsg) {     this.newMsg = newMsg; }  public String getStatus() {     return status; }  public void setStatus(String status) {     this.status = status; }  public String getCategory() {     return category; }  public void setCategory(String type) {     this.category = type; }   The critical Controller code is:      // TableView --------------------------------------------------------------------------------  @FXML private TableView<Message> msgTableView;  @FXML private TableColumn<Message, LocalDate> StartDateTableCol;  @FXML private TableColumn<Message, LocalDate> EndDateTableCol;  @FXML private TableColumn<Message, String> MessageTableCol;  @FXML private TableColumn<Message, String> CategoryTableCol;  @FXML private TableColumn<Message, String> StatusTableCol;  @FXML private DatePicker startDatePicker;  @FXML private DatePicker endDatePicker;  @FXML private TextField msgTextField;  @FXML private ComboBox categoryComboBox;  @FXML private Button addButton;  @FXML private Button deleteButton;  @FXML private Button editButton;   public void saveLine() {      Message message = new Message();      message.setStartDate(startDatePicker.getValue());     message.setEndDate(endDatePicker.getValue());     message.setNewMsg(msgTextField.getText());     message.setStatus("active");      message.setCategory(categoryComboBox.getValue().toString());      msgTableView.getItems().add(message);      clearLine(); }  public void clearLine() {      System.out.println( "\nEntered clearAll() " );      startDatePicker.setValue(null);     endDatePicker.setValue(null);     msgTextField.clear();     categoryComboBox.setValue("Category"); }


A Blender user in the U.K. made this recreation of old BBC schedule slides from the 80s. If you're watch it closely, there seems to be some fluttering (or, as the user calls it 'twitter') in the lettering, especially the yellow ones with the black outlines. Does anyone know how to achieve this effect as well as how to create an old NTSC or PAL filter


Does name-combo 'Jarvanka' take singular or plural attributes?

Michael Wolff's new book Fire and Fury sure has generated quite a lot of controversy. However, one important topic seems to have been overlooked by the Mainstream Media: Wolff (or his editors) consistently use the singular verb form when describing actions taken by 'Jarvanka', Steve Bannon's catchy nickname for the Jared Kushner and Ivanka Trump duo. (For example, "Jarvanka was surprised" instead of "Jarvanka were surprised.")  Is this correct? or does Jarvanka take a 'were' as it most certainly is two people?  (Note: IMHO, this is not comparable to plural nouns such as media, because here Jarvanka is (or are) obviously two different distinct persons, unlike media which is merely a collective noun.)


Use of \hphantom{} at beginning of list \item

It seems that \hphantom{} is ignored at the beginning of an item.  The MWE below yields:  How to get "First" and "Second" aligned?. I know that you have to use \hspace*{} instead of \hspace{} at the beginning of a line, but it does not seem as if \hphantom*{} or \phantom*{} exist. Code: \documentclass{article} \usepackage{enumitem}  \begin{document} \begin{enumerate}     \item {}\hphantom{x }First Item.     \item x Second Item. \end{enumerate} \end{document}


Why not upvote the question count automatically every time any answer is upvoted?

Regardless of which answer is useful to a viewer, if an answer is upvoted, the question should automatically be upvoted as well.  Obviously the answer would not be posted unless the question existed. It should also be possible to upvote the question even if there is no acceptable answer, but limit the upvote of the question to 1 per viewer.


Is there a cap on reputation lost in a single day?

On any given day, you can earn . Is there a corresponding cap on reputation you can lose from downvotes? If not, why the distinction?


uniformly integrable family of functions equivalent statement

I am studying the fourth edition of Royden Real Analysis and I have tried to solve the following exercise:  Let $\mathcal{F}$ be a family of function, each of which is integrable over E. Show that $\mathcal{F}$ is uniformly integrable over E if and only if for each $\varepsilon>0$, there is a $\delta>0$ such that for each $f \in \mathcal{F}$,  $$\text{if}\; A \subset E\;\text{is measurable and }m(A)<\delta,\; \text{then}\; \Biggl|\int_Af\Biggr|<\varepsilon.$$  Solution:  The straight direction is obvious. Let $\epsilon>0$. Since $\mathcal{F}$ is uniformly integrable over E, there is a $\delta>0$such that for each $f \in \mathcal{F}$,  $$\text{if}\; A \subset E\;\text{is measurable and }m(A)<\delta,\; \text{then} \int_A|f|<\epsilon,$$ and therefore, $$\Biggl|\int_Af\Biggr|<\int_A|f|<\epsilon.$$  To show the opposite direction we suppose that for  each $\varepsilon>0$, there is a $\delta>0$ such that for each $f \in \mathcal{F}$,  $$\text{if}\; A \subset E\;\text{is measurable and }m(A)<\delta,\; \text{then}\; \Biggl|\int_Af\Biggr|<\varepsilon.$$ We also know that every $f \in \mathcal{F}$ is integrable so for fixed $f \in \mathcal{F}$ and fixed $\epsilon$, there is a $\delta_f>0$ such that,  $$\text{if}\; A \subset E\;\text{is measurable and }m(A)<\delta_f,\; \text{then}\; \int_A|f|<\epsilon.$$  My problem is that I cannot find a common $\delta$ for all $f$ to show the desire.


Generalised basis independent relationship between Von Neumann Entropy and Purity of a quantum state

I have been trying to find a generalized relationship between Von Neumann Entropy and Purity of a quantum state?  there is a discussion of a specific case for a qubit and a more general case of a multi-level system but, I believe these are relations for the system in a given state basis. Is there a to work this out some way in which we can keep this in a basis-independent formalism.


What exactly does the *frequency* of a photon mean?

If you emit a single photon, wait an interval, emit a second photon, wait the same interval, and keep repeating, is the resultant stream of photons describable by the frequency at which you emitted each one? Or does each photon have its own "frequency", independent of the rate of emission? I thought the former description explained the Doppler effect.


Alt + sysrq + REISUB doesn't reboot my laptop

On occasion, my laptop has become stuck so I've used the magic key combination of Alt + SysRq + REISUB to perform a safe reboot. However, it doesn't seem to work for me as when I press the B key to complete the magic key command it simply says, "resetting..." and doesn't do anything.  All of the other keys seem to work fine as it resets the keyboard layout, kills all tasks etc., but it doesn't seem to complete with a reboot.  I was under the impression that my laptop should reboot after the magic keys have all been pressed in the order of REISUB.


Why apt can't find the source code of any package?

I'm trying to download source code of certain packages, for example rhythmbox, for learning purposes. I want to do this through apt-get, with the apt-get source command.  For some reason, apt-get can't seem to find any package. I've tried several packages, and I keep getting this output from apt-get:  $ apt-get source rhythmbox Reading package lists... Done Building dependency tree        Reading state information... Done E: Unable to find a source package for rhythmbox   I've been searching for answers for quite some time now, but I can't find anyone with the same issue. apt-get works fine with installing and updating so apt-get works fine in my opinion. During the search I also learned that I had to enable the 'source code repositories' in Software Sources, so that's also enabled.  I am aware of the fact that (maybe only for certain packages, not sure) source packages can also be downloaded with bzr from Launchpad, but I want to know why this method won't work.


How to convert a 3x3 rotation matrix to quaternion form?

i trying do some revise for my test. i have trouble convert rotation matrix to quaternion form example given this matrix from quaternion <1,2,3,-5>, generate from  [ -0.7435898,  0.5641026, -0.3589744 ] [  0.0512821, -0.4871795, -0.8717949 ] [ -0.6666667, -0.6666667,  0.3333333 ] what the step to get back the quaternion form?


Front element shattered, can I have my lens repaired?

Can I send in for repair a lens that has a shattered front element?     UPDATE: The front element was not shattered, it was the UV filter. Factory diagnosis: Lens assembly had been impacted; cleaned and checked.  Helpful notes by Crowley, David Richerby (x2), Michael Clark (x2), and   mattdm (on element price vs UV filter).      Canon cleaned and checked my lens back to like new quality for $179 labor, no parts, not including shipping.      Jim Garrison answered my question, but Crazy Dino has the best info all around for a lens element shatter.   Original Question:  I recently opened my camera bag to find a shattered front element on a Canon EF 16-35mm f/2.8 L II USM lens.   There are a lot of micro glass shards on the second element.  Does anyone have experience with this sort of thing?  Some of the following are questions I have:   Can I get it repaired? What will the cost be roughly? Will the lens ever work the same and have a good image quality? Should I ship it as is, or attempt cleaning it with air? Where is the best place to cry a little?   Thanks, any good info on this would be appreciated.  I will never rest a lens on another lens, I nearly lost a 24-70mm L that shattered a UV filter also.   Good reason to have a UV always, never thought it could happen to me.  Update: Looking at it more it looks like maybe just the front ring came undone and the UV filter broke?  I can't remember what it looked like exactly before.  I threw away the glass shards (polished sand) in the Nevada desert.      UPDATE: Primary reason for thinking more than just the UV was broken,   UV filter split into two rings, depositing the locking collar into the   lens barrel.


I'd like to use  transistors for driving multiple low power solenoids, but looking at the datasheet I can't figure out what value the base resistor (R1) should be?          – Schematic created using


null pointer exception in getPropertyMsg?

Im trying to fix bugs, but i just cant find how to solve this part:  This is the error. The program runs a bit, then in throws null-pointer  Properties value: DEVELOPEMENT App is running... Exception in thread "main" java.lang.NullPointerException     at hu.citec.hazi.hazi.service.Service.print(Service.java:12)     at hu.citec.hazi.hazi.Main.run(Main.java:26)     at hu.citec.hazi.hazi.Main.main(Main.java:20)   my code: Repo class:  package hu.citec.hazi.hazi.repo;  import java.time.LocalDateTime;  @org.springframework.stereotype.Repository public class RepoImpl implements Repository {      public String getPropertyMsg() {         StringBuilder sb = new StringBuilder("Hello");         sb.append("\n")         .append("\t").append("HOME: ").append(System.getProperty("user.dir")).append("\n")         .append("\t").append("USER: ").append(System.getProperty("user")).append("\n")         .append("\t").append("TIME: ").append(LocalDateTime.now()).append("\n");          return sb.toString();     }      public String runTest(String msg) {         System.err.println(msg);         return msg;     } }   Repository interface:  package hu.citec.hazi.hazi.repo;  public interface Repository {  String getPropertyMsg();  String runTest(String msg); }   Service class:  package hu.citec.hazi.hazi.service;  import hu.citec.hazi.hazi.repo.Repository;  @org.springframework.stereotype.Service public class Service {  private Repository repo;   public String print() {     return repo.getPropertyMsg(); }  public String test(String msg) {     return  repo.runTest(msg); } }   MainConfig class:  package hu.citec.hazi.hazi.config;  import org.springframework.beans.factory.annotation.Value; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.ComponentScan; import org.springframework.context.annotation.PropertySource;  import hu.citec.hazi.hazi.entity.User;   @ComponentScan("hu.citec.hazi.hazi") @PropertySource({ "classpath:application.properties", "classpath:application-${spring.active.profiles}.properties" }) public class MainConfig {  @Bean public User defaultUser(@Value("${project.profile.name}") String name) {      System.out.println("Properties value: "+ name );     return new User(name); }    }   Main class:  package hu.citec.hazi.hazi;  import org.springframework.beans.factory.annotation.Autowired; import org.springframework.context.ApplicationContext; import org.springframework.context.annotation.AnnotationConfigApplicationContext; import org.springframework.stereotype.Component;  import hu.citec.hazi.hazi.config.MainConfig; import hu.citec.hazi.hazi.service.Service;  @Component public class Main {      @Autowired     private Service service;      public static void main(String[] args) {         ApplicationContext ctx = new AnnotationConfigApplicationContext(MainConfig.class);         Main main = ctx.getBean(Main.class);         main.run();     }      public void run() {         System.out.println("App is running...");          System.out.println("ÜDV! \n\t" + service.print() + "\n " +service.test("Sikeres teszt"));     } }   Maybe I have made some mistakes. Sorry about that.   I also got to write more details to make this qquestion pass.


Is the default constructor called differently when using parentheses versus nothing? (on a template class struct)

I've been writing some code for a project that includes OpenGL, and I've discovered weird behavior with my vec4 struct, of which I could not find an explanation.  Here's the relevant snippet of my code:  #include <iostream> using namespace std;  template <class T> struct vec4 {     T data[4];     vec4(T v1 = (T) 0, T v2 = (T) 0, T v3 = (T) 0, T v4 = (T) 1) {         data[0] = v1;         data[1] = v2;         data[2] = v3;         data[3] = v4;      }     void print() {         cout << "[ " << data[0] << ", " << data[1] << ", " << data[2] << ", " << data[3] << " ]" << endl;      } }; int main() {     vec4<int> test1;     //Instantiating like this is fine     test1.print();      vec4<int> test2();   //Instantiating like this leads to errors     test2.print();      vec4<int> test3(0);  //Instantiating like this is also fine     test3.print();      // ...      return 0;  }   As you can see, the only difference is using parentheses or not. When I use the parentheses, I get various errors such as:  main.cpp:222:11: error: request for member 'print' in 'test2', which is of non-class type 'vec4<int>()'  main.cpp:226:18: error: no match for 'operator*' (operand types are 'matrix<int>' and 'vec4<int>()')  I get none of these errors if I exclude the parentheses. (I should note that there is an operator overload function defined, but excluded from my snippet. It works with matrix<int> and vec4<int>.)  Does anyone have an explanation to this behavior? Are there any situations where such behavior could lead to problems?  Thank you!


Is it possible to run Pokemon Go with English without changing system locale?

Recently Pokemon GO updated and shows all users the language agree with the system locale.  My devices (iPhone SE and iPad mini) were set to use Chinese (Traditional) and so now it is not displaying English at all.  However, although I came from China, I live in Australia now and the kids are still learning Chinese from us whilst they can already read English pretty well.  So I wonder if I can make it display English again without having to change my system locale?


Can one article be published in two different language journals?

Is it possible to publish the same article in multiple journals published in different languages? For instance, I have a published SCI journal article, but I want to publish the same article in a domestic journal for a local research community as well and vice versa.  Will it be consider self-plagiarism?  How do I deal with the copyright issue, considering the publishers of the journals are different?


I have GeoServer (v2.2 from OpenGeo Suite) running on a test server hosting many different WMS services sourcing many different PostGIS db tables.  I want to push this setup onto a production server now but I'm not sure what the best method would be for migrating this info without recreating all the Workspaces, Stores, and WMS layers again.  Both servers are the same:  Windows Server 2008 R2 Standard  My thoughts so far are:   Stop GeoServer on test Make backup of all dbs in PGAdmin on test Restore backup(s) to production db Copy data directory from test and paste it to same location on production Start GeoServer on production   Thoughts?


How to Copy Millions of Files from Remote Server to Local One

I have this problem, I have an Ubuntu server (SSH enabled on port 4444). Inside this server there's a directory called /folder/a/, this directory literally contains millions of small size text files.  What i want to do is to find several thousands of files from those millions of files and copy or transfer those files to my local pc, i.e. using find command. When using scp or cpio it won't work properly.  Do you have any suggestion how to do this from my local pc, i.e not from running ssh terminal on my remote server.


What packages are required to make tasksel work on Xenial

I have a Xenial (upgraded from Trusty) 64 bit Desktop install. I've installed the tasksel package in order to install a LAMP server (required for ZoneMinder). When runing "sudo tasksel", it displays the various package groups, some (e.g. Ubuntu Desktop) being marked with a * to show that they are already installed. LAMP server is not marked with a *. So I move the red marker to the [ ] position opposite LAMP server. However, pressing the Enter or Return keys just exits tasksel. I've tried the * and x keys with no success: they do nothing. Am I missing some packages that tasksel requires?


Does editing a post make it more 'visible' on the list of questions?

The single answer I received to a question led me to understand how I really wanted to ask the question and to be more specific.  I've edited and expanded my question, but by now, the bulk of users looking at new questions have already viewed it, and only saw the old version of my question.  Do large edits 'bump' the question nearer to the top of the pile, so to speak, so that it will be viewed again?


Second order ODE - why the extra X for the solution?

Assuming I have the following homogeneous ODE equation: $$a\cdot y'' + b\cdot y' + c \cdot y = 0$$ Why for $(b^2 - 4\cdot a\cdot c=0) \quad $,(meaning, when $m_1=m_2$) then the solution is: $$y = C_1\cdot e^{m_{1}x} + C_2\cdot x \cdot e^{m_{2}x}$$ Why isn't it simply: $$y = C_1\cdot e^{m_{1}x} + C_2 \cdot e^{m_{2}x}$$ ? Also, why did they choose to multiply $C_2$ with $x$? Why not having a totally different approach for the solution when $(m1=m2)$ (e.g. diving the equation with $x$)?


13.04 wont start, "cant identify screen, graphics card etc..." error

Trying to start 13.04 after a recent installation.    A window appears that says "Cannot correctly detect the screen, graphics card, and input device settings" You will need to set these yourself.  Standby as display restarts"  Then there is only a terminal window, which says "* Checking battery state    ...  [ok]"  and it just hangs there and does nothing and does not respond to any input"  any suggestions?  thanks, stephen


What is the relationship between Unix, Linux, Ubuntu, Debian and Android?

What is the relationship between Unix, Linux, Ubuntu, and Debian?    I suspect they are all Operating Systems that are based upon one another - similar to how Windows is based on DOS. Is my suspicion correct? Do these operating systems have the same type of relationship with each other as Windows has with DOS? Are they related to DOS or Windows in any way?


My question is : Suppose a block of mass $m$ is kept on an ideal floor. To lift it, why I need to apply an upward force which is of magnitude $mg$? Force $mg$ is acting on the block in downward direction which is the force of gravity. If I apply an upward force $mg$ it just makes net force acting on the block zero. Then why the it would move upward? And why with zero acceleration


How to dual boot windows10 & ubuntu15.04? I have legacy bias mode. Every time I try to make the dual boot, it shows I have to format my full computer. I'm not sure if it'll work either. So, please help me.


Is it a bad idea to keep laptop suspended most of the time?

I have an old netbook (Acer Aspire One 531h) which I am planning on setting up as a Xubuntu powered Plex client for my parents. They will control it using the android Plex app and a WoL utility for power-on.  However waking up from hibernation takes a little longer than I would like and I was wondering if it was a bad idea (power-consumption-wise) to keep the little guy suspended most of the time instead.  The battery is long dead and disposed of.


Problem dealing with $\sum \frac{\sin(n)}{n}$ and its convergence

$$\text{If} \ S=\displaystyle\sum_{n=1}^{\infty}\dfrac{\sin (n)}{n}, \ \text{then what is} \ 2S+1$$   I know that $\sum \frac{\sin(n)}{n}$ converges. But now what do I do?


Xubuntu reopens last session applications even though it shouldn't

There's something strange going on with my Xubuntu setup (13.10 at the moment, but I remember having this issue in 13.04 as well, before upgrading). Each time I log in, the system reopens the applications that I didn't close before shutting down the computer last time. This is strange since in the session and startup settings I don't have the Automatically save session on logout setting checked. What can I do to fix this issue ?


Digitalocean droplet boot drops to a (initramfs) prompts/busybox

I have digitalocean droplet ( a server). I restarted the droplet. Then Boot drops to a (initramfs) prompts/busybox. I found a solution:  But fsck command not available. Available Commands are:  The error is:  What can I do about that?


Don't impose delay loading Close dialog when you haven't just loaded it

Because of , clicking the "close" link on a question that's been edited (for me usually the edit comes in a half-second before, as I'm reaching for the link) reloads the question instead of opening the Close dialog. Clicking it again to actually open the close dialog says     You may only open the Close dialog every three seconds   I didn't open it, I refreshed the post.  And yes, there are lots of times when the post edit is so trivial it's obvious in less than a second that it doesn't affect the need to close the question.


Can I take a US domestic flight as a foreigner without my passport?

I'm a foreigner in the US with a J1 visa. I don't have my passport with me and I have a flight from Boston to Miami. Can I fly without the passport?  I only have a copy of my passport and visa because my original passport is stuck in the Canadian visa centre in NY (because I requested a travel visa to visit Canada).  I was supposed to receive my passport back days ago, but it's taking longer than it usually does. It won't be delivered to me in time for my flight to Miami. The other documents I have are my own country's ID, and an international drivers licence.  Is there any way I can still fly?


Can we have a full list of related questions?

When viewing a question, there is a list on the right that displays related questions. However, I suspect they do not display the full list of related questions since the size of the list seems to be fixed at 10.  Sometimes, I would like to have a more exhaustive list of related questions. Could that feature be added? For example, a whole new page with a list of questions related to a particular question.


I just started using Blender. I have a png file used as texture, and I would like to apply a glossy finish only to one colour of the image. Is there any way I can do it? Thank you in advance!


I am trying to implement this Block Diagram:   Forget about the math, I can do it. I just want to implement the diagram. I used the example ; it is nice, but whenever I remove the "measurement" block, the feedback path cannot be obtained unless directly (-180 deg). Also, I am still unable to get more than one box on top of each other.    MWE:  \documentclass{article}  \usepackage{tikz} \usetikzlibrary{shapes,arrows} \begin{document}  \tikzstyle{block} = [draw, fill=white, rectangle,      minimum height=3em, minimum width=6em] \tikzstyle{sum} = [draw, fill=white, circle, node distance=1cm] \tikzstyle{input} = [coordinate] \tikzstyle{output} = [coordinate] \tikzstyle{pinstyle} = [pin edge={to-,thin,black}]  \begin{tikzpicture}[auto, node distance=2cm,>=latex']      \node [input, name=input] {};     \node [sum, right of=input] (sum) {};     \node [block, right of=sum] (controller) {Controller};     \node [block, right of=controller, pin={[pinstyle]above:D},             node distance=3cm] (system) {System};      \draw [->] (controller) -- node[name=u] {$u$} (system);     \node [output, right of=system] (output) {};     \node [block, below of=u] (measurements) {Measurements};      \draw [draw,->] (input) -- node {$r$} (sum);     \draw [->] (sum) -- node {$e$} (controller);     \draw [->] (system) -- node [name=y] {$y$}(output);     \draw [->] (y) |- (measurements);     \draw [->] (measurements) -| node[pos=0.99] {$-$}          node [near end] {$y_m$} (sum); \end{tikzpicture} \end{document}


Why does Newton's Third Law actually work?

My father explained to me how rockets work and he told me that Newton's Third Law of motion worked here. I asked him why it works and he didn't answer. I have wasted over a week thinking about this problem and now I am giving up. Can anyone explain why Newton's Third Law works? For reference, Newton's third law:  To every action there is always opposed an equal reaction: or the mutual actions of two bodies upon each other are always equal, and directed to contrary parts.


This question sounds noob to me but I am confused after being away from computing for some time (maybe I have had serious concussions or a brain tumor).  I bought a laptop some while ago and thought it was cool to let the salesmen dual boot it with some Ubuntu LTS. Now I am stuck with Ubuntu 17.10 and I do not have a clue how to fix this. Some features I need (e.g. RStudio) are problematic on this Ubuntu version and I just like feeling comfort with a LTS.   I think the easiest way is to just add 16.04 to a new partition but I can not even find out how to add partitions in linux and nothing comes up when writing grub in the dashboard.   I have often set up dual-boot with Windows and various distros but for some reason I am stuck now.


Can I start Debian on a text virtual console in a virtual machine?

I have created a Debian virtual machine in virt-manager/KVM/QEMU.   When I run the Debian virtual machine, I don't really need the desktop environment, which is also resource consuming. Can I start Debian only on a text virtual console (e.g. like ctrl-alt-f1) instead of the graphical virtual console (i.e. ctrl-alt-f7) on the virtual machine?   Thanks.


Saving a file in gedit prints a warning in terminal

I recently installed a GRUB theme from  on Ubuntu 20.04 LTS (my PC is Windows 10 dual-boot with Ubuntu). To install the theme successfully, the file at /etc/default/grub needs to be edited. So I used sudo gedit /etc/default/grub command to do so. After editing when I save it I, see the following warning in Terminal:  (gedit:7169): Tepl-WARNING **: 21:13:18.135: GVfs metadata is not supported. Fallback to TeplMetadataManager. Either GVfs is not correctly installed or GVfs metadata are not supported on this platform. In the latter case, you should configure Tepl with --disable-gvfs-metadata.  Later on I also edited the grub menu by editing the file at /boot/grub/grub.cfg by using sudo gedit /boot/grub/grub.cfg. Upon saving the file I got a similar warning  (gedit:8887): Tepl-WARNING **: 21:18:46.163: GVfs metadata is not supported. Fallback to TeplMetadataManager. Either GVfs is not correctly installed or GVfs metadata are not supported on this platform. In the latter case, you should configure Tepl with --disable-gvfs-metadata.  Can someone tell me the reason? And also how to deal with it?


How to change the color scheme in KeyNote 6?

In Keynote 6, each Theme comes with a color scheme. I cannot figure out where this color scheme is defined, nor how to change it.  How to change the color scheme?    Or this one from a different template:


In Java, why do people prepend fields with `this`?

When referencing class variables, why do people prepend it with this? I'm not talking about the case when this is used to disambiguate from method parameters, but rather when it seems unnecessary.  Example:  public class Person {             private String name;      public String toString() {         return this.name;     } }   In toString, why not just reference name as name?  return name;   What does this.name buy?   a stackoverflow question whose code has this pre-pending.


In a particular Bayesian problem, I have encountered a choice of parameters that leads to a uniform posterior distribution. Given prior \begin{equation}     p(\boldsymbol{\pi}) =Dirichlet(\boldsymbol{\alpha}), \quad \text{with}\ \boldsymbol{\alpha} = [0,\dots,0]. \end{equation} we consider a multinomial distribution whose support is $\{x_1, x_2, \dots, x_n\}$ and $\text{Pr}(X=x_i)=\pi_i(\sum_i\pi_i=1)$ \begin{equation}     \label{eq:likelihood}     p(X|\boldsymbol{\pi}) = \mathcal{M}ulti_{k}(n,\boldsymbol{\pi}), \end{equation} we find the posterior \begin{align*}     p(\boldsymbol{\pi}|X) &\propto p(X|\boldsymbol{\pi})p(\boldsymbol{\pi})\\     & \propto \prod_{i}\pi_i\prod_{i}\pi_{i}^{\alpha_i-1}\\     & \propto \prod_i\pi_i^{\alpha_i}. \end{align*} to be a uniform distribution \begin{equation}     p(\boldsymbol{\pi}|X) =Dirichlet(\boldsymbol{\alpha}), \quad \text{with}\ \boldsymbol{\alpha} = [1,\dots,1]. \end{equation} I was wondering if it is uniform, why is this called a posterior then? How can we have a posterior distribution that is a uniform distribution?


Windows 8 : how to enable "net rpc shutdown"

I'm a student and have a few servers/clients at home. One of those computers is running on Windows 8. On this network, I have an embedded system on Debian that I use for VPN and SMB purposes. I has already scripts that do some wakeOnLan.  I've found recently that I can shutdown computers with Samba, using the command net rpc shutdown.  However, when I do it, i get an error:     could not initialise pipe \winreg. Error was NT_STATUS_OBJECT_NAME_NOT_FOUND   I've found  that a local user was, by default, not allowed to perform a shutdown remotely.  I've searched into the register the key to edit,  but I couldn't find it. It's at another place.  So, do you know how I can enable this "shutdown on LAN"?


Regain access to my broken Gmail account from Temporary Error 500, Numeric Code 93

Since August 1st I've been getting this error when trying to login to my gmail account:     Temporary Error (500)      We’re sorry, but your Gmail account is temporarily unavailable. We apologize for the inconvenience and suggest trying again in a few minutes.      If the issue persists, please visit the Gmail Help Center »      Try Again Sign Out      Hide Detailed Technical Info   Numeric Code: 93   I've emailed Gmail support several times with no response after their autoresponder, and I've posted to the .  Absolutely no response.  It's been more than 10 days now, and I'm starting to get desperate!  Can anyone give me any ideas for how I might get this issue resolved.  If any Googlers happen to read this – you'll receive much good karma if you notify one of the engineers of my plight! :-)


For use in a shell-script, I'm looking for a commandline-way to get the destination of a symbolic link. The closest I've come so far is stat -N src, which outputs src -> dst. Of course I could parse the output and get dst, but I wonder if there is some direct way of getting the destination.


How can a Lagrangian determine how its fields transform?

Here's an excerpt from Schwartz's QFT text, section 8.2, that's always totally confused me.     A natural guess for the Lagrangian of a spin 1 field is   $$\mathcal{L} = - \frac12 \partial_\nu A_\mu \partial_\nu A_\mu + \frac12 m^2 A_\mu A_\mu.$$   Then the equations of motion are   $$(\Box + m^2) A_\mu = 0.$$   In fact, this Lagrangian is not the Lagrangian for a massive spin-1 field, but the Lagrangian for four massive scalar fields, $A_0$ through $A_3$. You might wonder how we know if $A_\mu$ transforms as a vector or four scalars. As a very general statement, we do not get to impose symmetries on a theory. We just pick the Lagrangian, and let the theory go.   I find this passage incredibly confusing. First, how is it apparent that there are four massive scalar fields, when it looks like the equation of motion works either way?  Second, Schwartz seems to be saying that the Lagrangian determines how the fields inside it transform, which seems exactly backward to me. Don't we first postulate that fields exists with certain transformation properties, then write down scalar Lagrangians for them? That's exactly how we construct the Dirac spinor, for instance -- we write down how it transforms, and only afterward write down the Dirac Lagrangian.


Android/Java - How to detect whether an emoji/emoticon is present in the string?

I'm building a chat application in which I'll be using emoticons, so the problem is that when I enter and send the text, for eg. -  "Hahha this is so funny 😂" In MySQL, it gets saved as "Hahha this is so funny ??"  Can anyone tell me how to detect whether the string being saved to server contains an emoji and if it does, then accordingly convert the emoji part to special unicode format?  Thanks a ton!


I want a workflow that will email attachments

I'm creating a custom list for a helpdesk app.  I want the user to fill out a form in sharepoint (2010) and add attachments from screenshots, etc.  The workflow should send an email to our helpdesk system with the files attached.  Using sharepoint designer, i can only say yes there is an attachment, but i can't seem to attach the file to the email.  Any suggestions?


My ubuntu used to play music or vids by pushing the space bar while the cursor is over the file. How can I get this back on 14.10?


Where was this night time photograph taken (Windows 10 lock screen image)?

This picture was on my Windows 10 lock screen and I can't find any information.


Partition size 128GB but only 64GB detected

I used dd to copy an Ubuntu 18.04 installation from a 64GB partition on drive X to a 128GB partition on drive Y. See the below images for the problem; I am still limited to 64GB despite having a 128GB partition.         EDIT: Answer is below. I used resize2fs to grow the filesystem.


Paired t-test or Wilcoxon signed sum rank test for a slightly skewed data with a small sample size of 21?

I have a paired sample data with n=21. The two values V1 and V2 are from two different time points for the same group. I want to see if there is any improvement/reduction in values at time 2(V2). Of course, the first thing that comes to my mind is the paired t-test for which differences (D=V2-V1) have to be normally distributed. These are ,  and  of the differences data. The data looks slightly skewed but I'm not sure if I should go with t-test as the sample size is small (n=21). From Shaipro Wilk test, I'm getting p value as 0.025 and W=0.89 which rejects the null hypothesis that the data is normal. I'm thinking of an alternative to t-test such as Wilcoxon- signed rank sum test. Not sure which method is more appropriate. Also, how important is it for the data to be symmetrical for Wilcoxon test? From the box plot, it doesn't look so symmetrical. I'm kinda confused as to how to proceed and would really appreciate any help.    This is how the data looks like:               V1          V2      D(V2-V1) 1          2.5         2.0     -0.5 2          3.5         1.5     -2.0 3          2.0         2.0      0.0 4          1.5         4.0      2.5 5          4.0         3.5     -0.5 6          3.5         4.0      0.5 7          3.0         3.0      0.0 8          2.5         2.0     -0.5 9          4.0         3.5     -0.5 10         3.5         2.5     -1.0 11         3.5         3.5      0.0 12         2.5         1.5     -1.0 13         2.0         2.0      0.0 14         3.0         3.0      0.0 15         1.5         2.5      1.0 16         1.5         1.5      0.0 17         1.5         1.5      0.0 18         2.0         2.5      0.5 19         3.5         2.5     -1.0 20         1.5         1.5      0.0 21         3.0         2.0     -1.0


Should this verb be in the third-person singular form, the infinitive form, or the present participle form?

Watching a game review, I've noticed a phrase whose meaning confused me. The reason why I got confused is that the author used a base form of the verb "to explore" in pair with the singular subject "friend". The question is, is it correct to do this? I will write below two more options as I would use this verb in that case. Could you also explain if my bets are correct or, maybe, even preferable (I doubt it)? Here's the original sentence:  Watching my friend explore the environment with only a sense of wonder was my favourite part of the game.  Needless to say, this sentence might be grammatically correct, furthermore, it sounds natural for me, yet I must admit I do not speak and write English perfectly, not even close. These are two more mentioned options:  Watching my friend exploring the environment with only a sense of wonder was my favourite part of the game.  or  Watching my friend explores the environment with only a sense of wonder was my favourite part of the game.  Are these two both also acceptable? I appreciate your help. Besides, I ask for your forgiveness for the mistakes if there are some in my question.


Unable to use user fields from the global variable $user

I have created a module where I am declaring $user as global variable in hook_init().  I can access the values of $user->x_field in page.tpl.php. When I try to use $user->x_field in hook_contents($display), it causes the following error:     Undefined variable:x_field   Can I use the user fields in hook_contents()? Am I doing it the wrong way?


With Permanent magnet or electrificated sticks to create EM waves

I studied that the EM waves run through the space, with each electric field and magnetic field oscillating and inducing each other. And I had thought-experiment that it could be possible to make EM waves with manual steps(or mechanical) -  shaking permanent magnet or electrificated sticks. Is it possbile enough to make EM waves in the way i assumed? If it is, please hyperlink the related research.


I was wondering if there is a way to install Chromium snap version 87 along side with the current one. With snap info chromium you only get these versions:  channels:    latest/stable:    88.0.4324.96 2021-01-26 (1466) 142MB -   latest/candidate: 88.0.4324.96 2021-01-26 (1466) 142MB -   latest/beta:      89.0.4389.23 2021-01-30 (1470) 143MB -   latest/edge:      90.0.4400.8  2021-01-30 (1471) 146MB - installed:          88.0.4324.96            (1466) 142MB -    What if I needed both version 88 and 87 as I have some old devices that have  web management that needs Adobe Flash Player that has been dismissed since 12th January 2021. Wanted to keep Chromium version 87, only to manage these old devices and use current Chromium version to surf the web.  Thanks for you help. Carla


Can I use Ryanair Online Check-in with a permanent resident card?

I'm travelling to Italy from Greece for Christmas. I have a valid Russian Passport and a Permanent residence for EU family member card (which allows me to travel to Schengen countries).   Since Ryanair support wasn't very helpful, I want to know if I need to check-in at the airport to show my card, since online check-in only has an option for my passport.


Backing files up with Dropbox and Google Drive simultaneously

I know there are potentially ways to do this by putting your dropbox folders within your Google Drive folder, but it makes me a bit nervous. I have plenty of room on my hard drive, so figured maybe the best solution would be to just have a secondary directory tree for Google Drive that would "mirror" most of the folders from my Dropbox folder tree.  However, I don't want to have to manually manage every time I make changes.  I'm wondering if there is an application that would either immediately or on a schedule (say every night at 3am), make the changes in the Google Drive folder that had just been made in the Dropbox one?  I'm sure there are probably many out there that do this, but I guess I'm looking for the most reliable, well-known ones, preferably free, or at least under $20 if possible.


I'm having a problem with my Dell Inspiron 1564,   I am getting this error:  problem Kernel panic - not syncing: fatal exception in interrupt drm_kms_helper:: panic occurred, switching back to text console   I've found that it is probably due to the Broadcomm STA wireless driver.  But I am not sure how to solve the issue, does anyone know what I should do/try ?


How to test for 3 or more items in Minecraft inventory?

I built a town in Minecraft, and I want to add a currency system. I know you can test for exactly a certain number with /execute; however, it's very annoying to have to sort out  EXACTLY the amount needed to buy something.  So my question: Is there a way to test for 3 or more of an item? Like, if you're holding 64 currency and the item you're buying costs 3?


what different between int &p= n; int *q = &n;?

1)what different between int &p= n and int *q = &n in this code they do same thing. 2)what do & exactly(maybe return addres variable or something different?)     void foo(int &p){         p++;     }     int main(){              int n = 5;                   foo(n);              int &p= n;         int *q = &n;              cout << *q;         cout << p; }


How to solve :i have the following inequality involving absolute value in both sides ... what is the general method to solve? thanks for help $$|3 x-2|<|x+1|?$$


When i Import an obj it imports far away from the origin

Title says all how do i make it so the obj is imported to the origin, it was working fine yesterday...


How to add user to another group in Ubuntu?

My current groups: chris@Host:/opt/tomcat$ groups chris adm cdrom sudo dip plugdev lpadmin lxd sambashare  If I tried to add to group named tomcat: $sudo usermod -a -G tomcat chris  but the group is not added, after viewing the groups command again: chris adm cdrom sudo dip plugdev lpadmin lxd sambashare  simply no change. Why? I can see the my group be added to tomcat's: cat /etc/group: ...  tomcat:x:1001:chris  But still I do not have permission from that group (so I am not in there). Why? How's that possible?


Let $f = u +iv$ be holomorphic in domain $D$ such that $f$ is nonezero in $D$. prove that $$ h=\frac{u \frac{\partial u}{\partial x}+v \frac{\partial v}{\partial x}}{u^{2}+v^{2}} $$ is harmonic I tried to apply Cauchy-Riemann equations and didn't find anything, what is the "trick" here? what is the right attitude?


Can i install Ubuntu on a samsung GT-M3710, it doesn't have android, it has SHP.  Thank you very much.


In set theory, how are real numbers represented as sets?

In set theory, if natural numbers are represented by nested sets that include the empty set, how are the rest of the real numbers represented as sets?    Thanks for the answers. Several answers basically said for irrational numbers that  A Dedekind cut is a pair of sets of rational numbers $\{L, R\}$. The set of real numbers is defined to be the set of all Dedekind cuts, where a Dedekind cut is a pair of sets of rational numbers $\{L, R\}$ which have no elements in common, and where all the elements of $L$ are less than any element of $R$.  Each Dedekind cut is a real number. This is where I have a problem - surely that can’t be correct. The set $L$ is a set of all rationals, and there must be a rational in the set $L$ that is greater than all other rationals in that set, even if we have no method of determining it. And similarly, there must be a rational in the set $R$ that is less than all other rationals in that set, even if we have no method of determining it. If every irrational number has a corresponding set $L$, then each irrational number has some such corresponding largest element of that set $L$, and then each irrational number has some corresponding rational number. And that would mean that the irrational numbers are countable. So, with Dedekind cuts,  the only conclusion is that there must be irrational numbers $x$ which are either greater or lesser than some irrational cut $y$ of the rationals, and between $x$ and $y$ there is no rational number.  But that is impossible, so that the Dedekind cuts cannot be the correct representation of the real numbers.  Surely the problem with Dedekind cuts is in using sets of rationals that include all rationals up to a certain rational. But there is an alternative method of representing irrationals can be defined in terms of infinite sets of rational numbers. For example, in binary notation, the non-integer part of $\pi$ is $.00100100\ 00111111\ 01101010\ 10001$. You define a set by: if the nth digit is a $1$, then  the natural number $n$ is in the set. And then we have that, for the real numbers between $0$ and $1$, that the set of real numbers is simply the set of all subsets of natural numbers. Each subset corresponds to some real number between $0$ and $1$.  And in this way, all real numbers can be considered to be some set based only on nested sets of the empty set.  But I still haven’t got a satisfactory answer for how negative numbers can be represented in terms only of sets containing the empty set. Any ideas?


Can I make a "fan game" with characters of one game that already exists?

(I'm sorry about my english, I'm from Chile)  Hi! I'm making a game based on Alone In The Dark, and the history would happen before the events on the game of PS1. However, I would like to make a game with the character Aline, but with 10 years old. The game mechanism would be the same, and the name of a lot of characters and places. I don't really want to make any money, I just want to make a good game, I love the AiTD game. Can I do that or I can be on jail because of that? Thanks!


How to Join Games with Minecraft Pocket Edition 0.7

I can't find how to join games with the latest 0.7 Pocket Edition update with an iPad and iPod over wifi. I see the realm options but I get the message "there are no more open server slots right now". Local server multiplayer is switched on for both devices.


I've read the codex article about  and I understood that it is possible to order by Modified date. But I couldn't find where should I edit.   How WordPress post order by modified date including home page as well as categories page and tag pages?


For any natural number $n$ prove that there exist natural numbers $a,b,c$ for which $$n=a^2+b^2-c^2.$$  I think we can have a proof by induction because :   If $n=0$ we choose $a=b=c=0$ or $a=0,b=c$.  If $n=1$ we choose $a=1,b=c$.  Now we need to prove the relationship holds for $n+1$ but I can't prove that.


If $M$ is an $R$-module and $I\subseteq\mathrm{Ann}(M)$ an ideal, then $M$ has a structure of $R/I$-module

Let $M$ be an $R$-module and let $I$ be an ideal of $R$ such that $I$ is a subset of $\mathrm{Ann}(M)$. Define a product of an element of $R/I$ by an element of $M$ as follows: $$(r+I)\cdot m=rm.$$ (a) Show that this product is well defined. (b) Show that this product, together with the sum of elements of $M$, turns $M$ into an $R/I$-module.  My answer for (a): Let $r+I,s+I \in R/I$ such that $r+I=s+I$. Then $(r+I)m=(s+I)m$, for all $m \in M$. Then $rm=sm \implies r=s$  (since the inverse of $m$ is in $M$), so the product is well defined.  Is my answer to (a) correct?  How can I use Ann(M) to answer (b)?


In my object record type i have created formula field. Now i want my formula field to work as below.  If Basement__c = NA and Property__r.Basement__c = NA OR  Basement__c = Crawl and Property__r.Basement__c = Crawl OR  Basement__c = Slab and Property__r.Basement__c = Slab Then it will return Type__c(formula field) = "MAtch"  And (Another rule) Basement__c DOES NOT contain any of the following "N/A,Crawl,Slab,None and Property__r.Basement__c Does not contain any of this then formula field will return "HAs basement"  How can i achieve this? Please help.


Variance of the sum of 3 Pairwise Independent random variables

We have 3  independent Bernoulli random variables with parameter 1/2. They are pairwise independent but not mutually independent. I know that the variance of Var[A] = Var[B] = Var [C] = 0.25 due to the formula of Bernoulli random variables variance: p * (1-p). Therefore, I know that Var[A] + Var[B] + Var [C] = 0.75. I know as well that Var[A + B + C] = 0.75 because Var[A + B + C] = Var[A] + Var[B] + Var [C] when the variables are pairwise independent.  However, I am not able to calculate by myself Var[A + B + C]. Can you please guide mr algebraically?   Thanks


Show that $C^1([a,b])$ is a complete space w.r.t. some special metric

Let $C^1([a,b])$ denote the space of all continously differentiable functions on $[a,b], a,b\in\mathbb{R}$.  On this space, define the following metric: $$ d(f,g)=d_{\infty}(f,g)+d_{\infty}(f',g'), $$ where $$ d_{\infty}(f,g):=\lVert f-g\rVert_{\infty}:=\sup_{x\in [a,b]}\lvert f(x)-g(x)\rvert $$ and, similarly, $d(f',g')_{\infty}$ is defined.    So I have to show that each Cauchy sequence $(f_n)$ in $C^{1}([a,b])$ converges in $C^1([a,b])$. Don't really have an idea, but at least I can write down what Cauchy sequence means.  Let $(f_n)$ be some Cauchy-sequence in $C^1([a,b])$, i.e. for all $\varepsilon >0$ there is some $N\in\mathbb{N}$ such that $$ \lVert f_n-f_m\rVert_{\infty}+\lVert f_n'-f_m'\rVert_{\infty}\leq\varepsilon~~\forall n,m\geq N. $$  Now, I have to find some $f\in C^1([a,b])$ such that $f_n\to f$, i.e. for all $\varepsilon >0$ there exists some $N\in\mathbb{N}$ such that $$ \lVert f_n-f\rVert_{\infty}+\lVert f_n'-f'\rVert_{\infty}\leq\varepsilon~~\forall n\geq N. $$


On changing jar path Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException appears

I exported executable jar and while exporting ,I provide path D:/ in eclipse. When i execute jar from same path,it works fine but when I placed the same jar in a folder in same directory and execute it shows "Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException". Note-jar was exported using package required libraries option.


Converting English into first order predicate logic

S(x), which stands for “x is a surgeon”  P(x, y), which stands for “x is a patient of y”  R(x), which stands for “x recovers”  H(x), which stands for “x is happy”  1>"A surgeon with no patients is happy" means: for any person xx, if xx is a surgeon and there is no person yy for which yy is a patient of xx, then xx is happy.  2> "A surgeon is happy if all her patients recover" means: for any person xx, if xx is a surgeon and - if for every person yy for which yy is a patient of xx, we have that yy recovers - then xx is happy.  I have these as solution:  1:∀(x) ( S(x)∧ ∀(y)P(y,x) → H(x) ) 2: ∀(x) [ { S(x)∧ (∀(y)P(y,x) ∧ R(y)) } → H(x)]  Are these okay?  And how do prove that 1 follows from 2 by resolution (not by drawing a truth table)?


changing your answer to match someone else's

Following sequence of events occurred on :   First answer was posted, but was wrong. I posted my answer, which was correct :-) First answer was then modified to match my answer (with attribution)   Meanwhile, the first answer got a total of four up-votes, some from when it was still wrong. My answer has one. There is no accepted answer yet.  I guess this falls into the "grin-and-bear-it-and-move-on" category? What are the ethics of essentially posting a different answer which is still timestamped with the time of an earlier, incorrect answer? Is this flaggable?


this developer name is invalid .provide the developer name for the report that contains the chart in salesforce1

I have a report which is showing fine in Salesforce classic but in salesforce1 it's giving this error      'this developer name is invalid .provide the developer name for the report that contains the chart'.   So what is the solution of this problem.


Color cells in Excel based on certain values

I have a list of 200 cells in Excel. I put in names and would like the text color in the cell or the background of the cell to change according to the name written. I use about 25 names.


Why is " I" not " me" required in this comparative clause?

He is taller than I. He is taller than me.  I saw both sentences on an official website of a famous university in Indiana, USA. On the grammar page, sentence one is an example of how personal pronouns are used. While sentence two is considered negative and ungrammatical. In the Oxford Dictionary, sentence two is correct because " than" is defined as a preposition. So, I'm wondering, which should I trust.


Which verbs apart from the pure copula follow the existential 'there'?

The existential 'there' is usually followed by a form of the verb 'to be', used as a pure copula.   For instance, rather than saying, a wrench is on the bench, you'd say there's a wrench on the bench.  Biber, Conrad and Leech (2002) list a number of syncategorematic/copular verbs which can also follow the existential 'there', eg:  There used to be a house ... there's supposed to be a plot ... there seems to have been a mistake ... there's said to be a ghost ...   They don't make a distinction which I've noticed about what I call 'emergent-type' verbs, always used in the past, describing, as I see it, an action which has emerged, but seems as yet incomplete, eg:  ...there arose such as clatter ... there appeared a great multitude ... there emerged, out of the freshly tilled soil, ...   I noticed today another type which I hadn't clocked before ... the use of the intransitive after 'Once upon a time', eg:  Once upon a time, there lived ...  I can't think of an instance where you'd use a transitive verb in this construction.  Are there any other types of verbs that can follow the existential 'there' in declarative sentences that you know of that I can add to my list?


problem with psfrag, eps file and texworks

I need to compile file using psfrag ans eps figure. I use texworks on windows and I have read that there are problems with pdflatex and I should go the latex->dvi->ps way but all I have found so far is not at all understandable for me... could you help me please? Thanks by advance :)


When $z$ is a complex number, does $\left(1 + \frac{z}{n}\right)^n$ converge to $e^z$?

I happened to read a statement related to my question in Ferguson's A Course in Large Sample Theory, where he stated:     $$\left(1 + \frac{\lambda_n(e^{it} - 1)}{n}\right)^n \to \exp[\lambda(e^{it} - 1)],$$   as $n \to \infty$, where $\lambda_n \to \lambda$ as $n \to \infty$.   So it looks like he used the property      $$\left(1 + \frac{z}{n}\right)^n \to e^z \tag{*}$$   as $n \to \infty$ tacitly, even when $z$ is a complex variable.   I understand that under the real setting, the proof of $e^x = \lim_{n \to \infty}\left(1 + \frac{x}{n}\right)^n$ relies on the ordering property of $\mathbb{R}$, but it is unlikely the same technique can be transferred to the complex domain.  Nevertheless, I guess this relation $(*)$ should be correct, but how do we show it rigorously (probably by using some complex analysis tools)?


Hey guys ive been thinking of buying a new smartphone and i want one that can play pokemon go perfectly and im thinking of iphone 5s,is it good for pokemon go?i have some doubts because people say needs 2gb ram and this iphone only has 1gb and im also worried about it getting outdated soon,can you help me,thanks


Automating the entry of Pathfinder Stat Block

How do I automate entering (not generate) statistics for a Pathfinder character or monster, and get some formatted text of a proper stat block that I can use in Microsoft Word or Adobe Indesign?


Why do we select the metric tensor for raising and lowering indices?

Any rank 2 tensor would do the same trick, right?  Then, which is the motivation for choosing the metric one?    Also, if you help me to prove that $g^{kp}g_{ip}=\delta^k_i$, I would be thankful too ^^


Idiom for someone "not from this world"?

Are there idioms (or single words) in English for people who behave like they have come from another world where everything is perfect and know nothing about the reality? They usually come up with ideas that can never work, but look attractive if you don't analyze them properly. They know nothing about science, and it seems they don't know that people lie, cheat and get violent. PS in Russian we usually use the word "эльфы" (elves) for such people, and they are supposedly visiting our world from the "world of elves". It's usually considered pejorative.


How to get latest Skype for Linux version from repository?

I have Skype installed which I got from the Canonical Partners repository, however after reading  I have come to understand that I can get this latest Alpha version from a repository too though no such update has come to me via the partner repository I have activated. So I have several questions on this matter:   So from which repository (unless that was just a mistake in the article) do I get it from? Is it available under a different name in the partner repository, or is there another official Skype repository? If it is the case that there is a more official repository to get this from then when it is no longer Alpha but instead Stable, will I be able to upgrade to it via the partner repository I currently have enabled or is it no longer support in there?   I am running Ubuntu GNOME 16.04 with GNOME 3.20.


Idle/Clicker games, supporting numbers many factors bigger than trillions in C# using Unity

Apologies for sloppy work and probably a poor grasp of fundamentals.  I have a (likely primitive) way to convert the ever increasing number values of my enemy hp into a string format to display in game. (K for thousands, M for millions, B for billions etc)    if (target_healthmax >= 1000)      {          if (target_healthmax >= 1000000000)          {              enemy_hp_text.text = "Health: " + (target_healthcur * 0.000000001f).ToString("#.00") + "/" + (target_healthmax * 0.000000001f).ToString("#.00") + "B";          }          else          {               if (target_healthmax >= 1000000)              {                  enemy_hp_text.text = "Health: " + (target_healthcur * 0.000001f).ToString("#.00") + "/" + (target_healthmax * 0.000001f).ToString("#.00") + "M";              }              else              {                  enemy_hp_text.text = "Health: " + (target_healthcur * 0.001f).ToString("#.00") + "/" + (target_healthmax * 0.001f).ToString("#.00") + "K";              }          }      }      else      {          enemy_hp_text.text = "Health: " + target_healthcur + "/" + target_healthmax;      }   but I stopped here after I noticed that although I could convert long numbers I would eventually hit a number too large to handle such as "-2.147484e+09" in my editor, and it would stop working.  I am using floats currently, is there a different type of variable that handles this easily? if not, what is an efficient way of solving this?  Would it be efficient to convert every new factor of 100 to a new variable and only handle the highest valued variable? eg  if num >= 1000, k += 1, num = 0;   if k>= 1000, m += 1, k = 0;  ...   (Please feel free to let me know anything about my post I may need to amend, I am new here)


Detecting, whether user enter a string value or number in to a input field

I have an input field and one button. When the user clicks the button, first I check whether they entered a number or not.  If it is a non-numeric string then nothing should happen. If it's a number then I will do some modification to the above gray div. When I enter a number and log its type to the console, it shows that the data type of the value is "string." So how do I check for the correct data type?  Here is the code:  <!DOCTYPE html>     <meta charset="utf-8">   <title>JS Bin</title>

<input type='text' id='myText'/>   <input type='button' value='click' id='myButton'/>
     CSS  #test {   width: 200px;   height: 200px;   background: gray; }   JavaScript  var el = document.getElementById('myButton'),     elOne = document.getElementById('myText'),     container = document.getElementById('test');  el.onclick = function(){   var data = elOne.value;    if(typeof data === 'number'){     console.log('number');   }else if(typeof data === 'string') {         console.log('string');   } };   And here is the jsbin link -


Reading a text on Transformation and Variate Generation that says that if   we want to simulate V, but we know only its conditional distribution given U, and we can simulate U   then we can simulate V as follows:   Draw u_sim from the marginal distribution of U Draw v_sim from the conditional distribution of V given U=u_sim   then v_sim is a variate from the marginal distribution of V. This is the part I don't understand: why are we allowed to say we have simulated from the marginal distribution of V and not the conditional $p(v|u)$?  Maybe this is just an approximation, and this distribution converges on $p(v)$ for large samples?


Neural networks when there are multiple correct answers

How could I train a potential neural network if there are multiple possible outputs?  For a simple example, if I'm trying to make a neural network that can find a valid solution to a quadratic equation, there could be 0, 1, or 2 correct answers. I want the network to be able to output all of the correct answers. Is this possible? If so, what techniques exist?


Reload bash's .profile without logging out and back in again

Is it possible to coerce bash to reload the .profile file without logging out and back in again?


I have installed all adobe flash version, for chrome, firefox or internet explorer I downloaded this software, Instant Demo  But when I launch it - it return me this message: Instant Demo requires Adobe Flash Player to be installed  But this is not possible because I have installed Adobe Flash I try to follow this tutorial  but seems doesn't work, however I have not found any Flash32_32_0_0_453.ocx or Flash64 are missing.


How to split two papers that Google Scholar incorrectly thinks are the same paper?

For some reason I don't understand, Google Scholar thinks two of my papers are the same, despite different titles, co-authors, and publication years. When I click on one ("Resonant absorption as mode conversion?") it lists 27 versions, most of which are the completely different paper ("Three Dimensional MHD Wave Propagation and Conversion to Alfvén Waves near the Solar Surface. I"). It therefore combines the citations for the two. How can I split them? I even tried deleting both papers and adding them manually from scratch, but without success.


Time travel manga where the female protagonist travels back in time before her death, to prevent her harsh life ahead

It’s a story of a female protagonist who has a harsh life. Just as she is about to die, she time travels back into her young self. To avoid the future she already lived, she decides to gets strong by learning swordsmanship. After a while, she joins the army under the command of a prince who wears an eye patch. She is quite OP, and helps the prince. It was kind of a medieval setting manga, with dukes and earls and count types. Time is when the use of sword and magic is prominent.


Just had a quick question regarding the uniqueness of the general solution of first-order differential equations:  For $x'(t)=Ax(t)$ where $A$ is an $n\times n$ matrix. and initial condition $x(0)=x_0$, the unique solution is $x(t)=e^{tA}x_0$.  The proof for showing that the solution is unique involves differentiating the matrix product $e^{-tA}x(t)$.  Could someone please explain why we always multiply by $e^{-tA}$.   Many thanks, Best.


Express the complex numbers given in Problem in the form $a+ib$ $i + i^2 + i^3 + \ldots + i^n \quad    (n > 4)$


Role of calcium chloride during competent cell preparation

I am aware of the fact that $CaCl_2$ settles down on the cell wall making it less negative may be by forming bond with Teichoic acid. Also due to the positive charge it attracts DNA (DNA is negatively charged due to phosphate group). But is there anything else the $CaCl_2$ does? Also if its the work of $CaCl_2$ why we are adding $MgCl_2$ first in the standard protocol of the making competent cell preparation chemically?


Let $\Omega \neq \mathbb{C}, \emptyset$ be a simply connected domain and $a \in \Omega.$ Let $f:\Omega \to \mathbb{D}$ be a conformal map such that $f(a)=0, f'(a)>0.$ Could anyone advise me how to prove $r=\text{min}_{z \in b\Omega}|z-a|\leq \dfrac{1}{f'(a)} \leq \text{max}_{z\in b\Omega}|z-a|=R \  ?$  Here is my attempt:   Define $\psi:\mathbb{D} \to \Omega, $ by $\psi(z)=a+rz.$   $\implies \psi(z) \in D(a,r) \subset \Omega \implies |(f \circ \psi)^{\prime}(0)| \leq 1,$ by Schwarz lemma  $\implies |f'(a)||\psi^{\prime}(0)| \leq 1$


Interpreting $Q_i=\partial_{\nu}T^{i \nu}$ from dust

I am working on Sean Carroll's problem 1.8     If $\partial_\nu T^{\mu \nu} = Q^\mu$, what physically does the spatial vector $Q^i$ represent? Use the dust energy momentum tensor to make your case.   I know this question has been asked and answered  and I understand that answer to a degree, but I'm trying to get it directly from dust and I'm not sure I'm doing it correctly or how to interpret what I'm getting.  The dust energy momentum tensor is  $$T^{\mu \nu}=\rho U^\mu U^\nu$$  Where $U$ is the four-velocity and $\rho$ is the energy density in the rest frame. Therefore what I'm looking at is  $$\partial_\nu T^{i \nu} = \partial_\nu \rho U^i U^\nu = \rho U^\nu \partial_\nu U^i+\rho U^i \partial_\nu U^\nu.$$  To examine the right-hand side of the above expression more simply I will choose to work in the rest frame of the dust. According to Carroll, the definition of dust is "a collection of particles at rest with respect to each other." Therefore, in the rest frame I expect all derivatives of velocity to be zero except the time derivative. Therefore I think I can simplify the above to  $$Q^i=\rho U^0 \frac{\partial U^i}{\partial t}+\rho U^i \frac{\partial U^0}{\partial t}.$$  If this is correct, I'm having some trouble understanding what each expression on the right hand side means. I'm not too sure how to proceed.


I have to find the continued fraction form of sqrt(6). I have tried it, and have the answers  but I can't get to the correct answer. If someone could help me that would be much appreciated. Thank you!


This thing ran out of the wall of my dorm hallway. It had a lot of what look like antennae, and it's very fast.    (click to enlarge)


scp permission denied when transferring files

I have 2 Ubuntu virtual machines on VMware workstation player 15. I want to import openvpn settings from a server to the client. I use the scp command, but I receive permission denied when using: scp openvpn-install.sh username@ipaddr:/root


What is a good set of naming conventions to use when developing on the Force.com platform?

I've looked in the Apex developer's guide and a saw the   which has basically only has this:   We recommend following Java standards for naming, that is, classes start with a capital letter, methods start with a lowercase verb, and variable names should be meaningful.   I'm looking for something more in depth, such as end all Controllers with Controller and their tests with ControllerTest, etc.  What is a good set of naming conventions to use when developing on the Force.com platofrm?  It would be preferable if the answer has something that handles custom objects, classes, visualforce pages, and components and not just Apex classes.


LED light needs replacing every few weeks

I have two GU5.3 bulbs in my bathroom - one of them went off a month or so ago so I bought the following 3 pack:   I've gone through 2 of the new bulbs in the space of weeks. I have never seen the bulbs fade out while being on, it's only when we turn the light switch on that they don't come back on (like this morning, I was first in the bathroom and the bulb was off again). No fuses blown or any indication of tripping.  How should I approach this?


Is it good practice to use non standard schema names in SQL Server?

If I have a database MyDB, is it considered good practice / bad practice to use schemas other than dbo?  For example:  MyDB.reports.YearlySales MyDB.reports.TopSellers MyDB.[data].ProviderX MyDB.[data].ProviderY etc


How to install openoffice? yes, I am total noob

I've downloaded the .deb version from the website. A tar.gz file. Then I extracted it. It gives me 3 folders: DEBS, Licences, readme.    There are loads of .deb files. So am I installing the one with the largest size called core04, because I did do this:     dpkg -i openoffice-core04_4.1.2-3_amd64.deb   it is not working.


I just watched a TV show and the guy says:     I ain't trying to fight with nobody with a baby.   So here, I can't understand the "nobody" since it make no sense to me, but it sounds like anybody, and if it's "I ain't trying to fight with anybody with a baby." that makes sense to me.


Why Data alignment of a 2 byte variable at a 2's multiple location in 4 byte compiler (32 bits) needed?

I'm learning Cpp from the basics, and when learning structure padding and data alignment, confused with the following:  struct A { char a; double b; char c; };  struct B { char a; short b; char c; };   Using MSVC++ 14.0 32 bit compiler  I understood the concept of data alignment by referring various pages on web.  In the 1st case, the sizeof(A) will give "24 (1 (a)+7(padding)+8(b)+1(c)+7(struct padding - since double is the max sized variable, padding is used to that value (8-1))". Here, I understood that because of cache lines (usually 32/64 bytes), double of 8 byte size is started at a location, which is a multiple of 8 instead of a multiple of 4 (even though compiler is 4 byte long - either case it requires 2 memory cycles but to avoid the data being split across 2 cache line location which is multiple of 8 is chosen)  But in the 2nd case, the sizeof(B) yields "6 (1(a) + 1(padding) + 2(b) + 1(c) + 1(padding)". This is of course the expected value from the rule (value of x bytes starts at a location which is multiple of x). But here, I did not understand why there is a need for b to start at a location which is multiple of 2?  Assuming that in struct B, a is placed at 0x00, why can't b placed at 0x01 and c at 0x03? Even in this case, the value of any of the variables (a,b or c) can be fetched in a single memory cycle (since 4 byte compiler) and this also doesn't result in 2 cache lines. I didn't understand the use of padding in this case.  Please help!!! I'm just curious to know, what advantage padding adds here?


Is a MOOC "degree" worth putting on your resume?

I've read an article about a Chemist who completed another bachelor's degree in Philosophy by finishing free MOOC courses. His new "degree' may not be academically accredited in any Graduate School of Philosophy. But is it still worth mentioning in your curriculum vitae/resume as a new "degree"?


finding limits for trinometric expression

I tried to solve this for finding limits, $$\lim_{x\to\infty} \frac{\sin^2(\sqrt{x+1}-\sqrt{x})}{1-\cos^2(\frac{1}{x})}$$ step 2 by applying conjugate $$\lim_{x\to\infty} \frac{\sin^2\left((\sqrt{x+1}-\sqrt{x})*\frac{\sqrt{x+1}+\sqrt{x}}{\sqrt{x+1}+\sqrt{x}}\right)}{1-\cos^2(\frac{1}{x})} = \lim_{x\to\infty} \frac{\sin^2\left(\frac{1}{\sqrt{x+1}+\sqrt{x}}\right)}{1-\cos^2(\frac{1}{x})}$$ and applying the basic trignometric rule, $$sin^2(\theta)+cos^2(\theta)=1$$ $$\lim_{x\to\infty} \frac{sin^2(\frac{1}{\sqrt(x+1)+\sqrt(x)})}{sin^2(\frac{1}{x})}$$ Here if I apply the limits I will get $$\frac{0}{0} $$form. Is there another way of simplification for the above step. The referred link for the same question haven't got better results. They to arrive at the solution $$\frac{\infty}{\infty}$$.  Thanks.


I have this unknown item in my Login Items  How can i view what this is? Not looking to remove just want to know what exact it is


Create cloud textured effect in Illustrator

I want to create an effect/color like this image of the cloud in the Parse.com logo. It is not quite white, and seems to have a texture. I am new to illustrator, but have a white "cloud" made thanks to some other tutorials. How do I proceed?


I am using Lubuntu 14.04.1. and my notebook is Lenovo ThinkPad e531-6885 ERG, I am connected to the internet through wire (eth0), and i guess it must work because under Windows 7 with MyPublicWifi it just flows amazingly.  So what do I need to do?  btw: the device which should I be able connect is Nexus 7 (2013)  Thanks in advance


grub rescue when trying to fix dualboot with Windows 8, what can I do?

I formatted the partition containing Ubuntu 13.04 running parallel with Windows 8, I then merged the partition disk into another disk and that is where the problem starts.  When I restart the computer and I get grub rescue.  I searched for solution on net they advised me to repair by booting with Windows CD, this resulted in another problem and now it's saying "operating system wasn't found " and I can not boot with Windows CD.  My OS is windows 8.  Please help me with a solution.


Letters f overlapping if used after each other in CMU Serif

When I use CMU Serif, letter "f" overlaps with other letters "f" when one follows another. Here is what it looks like:     What do I do to fix it? I don't think that the problem is with my PC. I tried it on different machines. Even Overleaf has the same problem with CMU Serif.


Is this a correct way for passing an environment variable in sudo ?  sudo -u www-data -b env FOOBAR="foobar" /home/user/folder/daemon


I am studying high school physics and it seems i have memorize the equation and use it mechanically in doing question and memorize lots of physical phenomena.I know a lot of physical phenomena can be explained by Huygen principle  (which i can't figure out the  whys and do not understand).There are so many things I don't understand and get the intuition.I know high school math and basic calculus,but it seems it doesn't help to understand.I am frustrated.I do not want to go along with memorizing and pass the exam as i think it is meaningless.We are not machines.Are there any resources that can help?Are there any books better explain high school physics and explain theories using math?


How to use ORDER by names after ordered by dates?

$query = "SELECT * FROM makale ORDER BY date ASC";     how can I add another ORDER after date ...?  I want rows ordered by dates and if same dates will be ordered by name ?  How can I do that?


When we observe a galaxy farther than 13 billion light years away, we see that galaxy as it was 13 billion years ago. But back then, that galaxy was much closer to us ,if indeed we live in an expanding and accelerating universe. The question is, why we see it so far when in fact it was very close to us and the time for the light to reach us was much shorter?


adding an openid that is already associated with stackoverflow not working

I have this account, with 2 IDs google and myopenid. I have another at work with a stackexchange ID, and not much experience. I would like to join them, or if not just add the work ID to this account.   So I tried to add the work ID (stackexchange ID). But this logged me out of this account, and into the other.  How can I add the work ID to this account? How can I now add another stackexchange ID to this account?


Are Linux utilities smart when running piped commands?

I was just running a few commands in a terminal and I started wondering, does Unix/Linux take shortcuts when running piped commands?  For example, let's say I have a file with one million lines, the first 10 of which contain hello world. If you run the command grep "hello world" file | head does the first command stop as soon as it finds 10 lines, or does it continue to search the entire file first?


how i can slove this error,SQLSTATE[42000]?

please help me to solve this error.i tired from searching solution... error: SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'WHERE name=NULL' at line 1  my database have 3 column=id(int),name(varchar),comment(varchar) and i want insert comment to it.  my php code :  <?php include "./Config.php"; include './MyPDO.php';    $response = array() ;   $connect = MyPDO::getInstance();    $name = $_REQUEST['name'];   $comment=$_REQUEST['comment'];          $query =  " INSERT INTO user "                 . " (comment) "                 . " VALUES "                 . " (:comment) "                 . " WHERE name=:name ";          $stmt = $connect->prepare($query);         $stmt->bindParam(":name",$name);         $stmt->bindParam(":comment",$comment);         try {                 $stmt->execute();                 $response['massage'] = "sucess";                 echo json_encode($response);                 exit;         } catch (PDOException $ex) {                  $response['massage'] = "error";                 $response['error']=$ex->getMessage();                 echo json_encode($response);         }


Find the total number of restricted compositions whose sum is $n$ using values of $1$ and $2$

I am just learning about recurrence relations and restricted compositions, can someone help me solve this problem


Question about difference between "rent" & "hire" & "take"

I want to rent a car. I want to hire a car. I want to take a car. ( Taxi )  What is the difference between these sentences in meaning? I need to say here I am not sure to have chosen the right word in the last sentence. Thank you do much in advance.


Where do my emails go when I click on 'Archive' in Gmail?

I selected a few important mails and mistakenly clicked on Archive.  I don't know where that mails are? Where can I find them?


What do we mean when we say "Let $x$ be an element of the set $\mathbb{R}$"?  Does $x$ represents only a single  element of set $\mathbb{R}$? or does $x$ represent all the element of set $\mathbb{R}$ simultaneously at the same time? People say that if $x\in\mathbb{R}$ then $x$ is any real number; that means $x$ represents all real numbers. But if $x$ is any real number then let's say $x=1$; so $x$ is one, then how it can represent all real numbers? Please help me I am very confused.