Time setting conflict in a dual boot system

My dual boot computer has Microsoft Windows and Ubuntu 13.10 installed. Suggestions on this website recommend setting the time parameter for Ubuntu to manual. I did that. In fact, I changed both the Microsoft Windows setting and the Ubuntu setting to manual. However, the time conflict still shows.   Why is Ubuntu picking up the system time setting as GMT + 0.00 and what can I do to change this bizarre error?


Difference between Generic collection and arrays of specific datatype

If I am not wrong Generic collection stores the objects of specific types. For example, List<String> stores objects of only String types. Also String[] arr = new String[size] stores the objects of String types. Both also support IEnumerable interface. So I want to know the differences between Generic Collection and Arrays of Specific types.


C# Generics specify type dynamically via reflection

I am trying to set type T of a generic list via reflection. Here is my code:  if (propertyType.IsGenericType && propertyType.GetGenericTypeDefinition() == typeof(List<>)) {     Type itemType = propertyType.GetGenericArguments()[0];     var result = MyGenericMethod<itemType>(url);    }   This is giving me a syntax error. How can set the type argument T of generic type via reflection ?  Thanks


Transparent/Invisible Mesh in Blender 2.8

Got back into Blender after a break but running into an issue where normal created mesh is invisible or takes the material of the colors surrounding it. I have XRay and such turned off. Any ideas what it might be? Here is a clip of the issue:  Thank you for any help.


Control LED using usb to parallel converter

I am using a laptop ( windows 7 and 64 bit) I bought usb to parallel connector as i want to control the LED's through the data lines of the parallel pin( 25 pins)... So i am trying indirectly to use a LPT port.. please tell me how to go about.. The code works fine on desktop PC when connected to parallel port..


Empirical bound on sum of electron and proton charge

Followup to "".  It is argued that even a tiny residual charge would result in huge amounts of electricity in bulk matter, everything would be different, etc. I do not find that a convincing answer: suppose $n$ protons plus $n+1$ electrons are neutral. Why wouldn't we also expect there to be $n$ protons to every $n+1$ electrons? That is, there is no bulk matter problem if every $n$'th atom is a negative ion (for hydrogen).  Now, what empirical lower bound can we give for $n$ in that kind of scenario?


Render looks "brighter" than in viewport preview

Somehow my viewport preview shows darker result than what comes out in render (check out in corner of the pic)  World strength is at zero and ambient occlusion is also disabled.  Floor is using bump and roughness from picture. Wall has adaptive subdivision surface  modifier.  All lit using planes with emission shaders.  I wanted to play around with render layers and maybe I screw some setting there, hope this helps.


Proof of the second symmetric derivative

Prove that if $f''(a)$ exists, then $$f''(a)=\lim_{h\to0}\frac{f(a+h)+f(a-h)-2f(a)}{h^{2}}.$$  I really have no idea on this one. Am I supposed to apply the mean value theorem?


How would I install Ubuntu with two hard drives

My laptop has two hard drives in it. And I want to install Ubuntu. Here's the thing, I want my SSD to be the hard drive that boots my system and allows it to run. I want the OS and system things there for the speed. Then, I want any downloads, documents, etc. To be on my separate HDD. Does anyone know how I could do this. Yes this is similar to my other question but that one was about how Ubuntu handles separate drives and this one is about how I could install Ubuntu with two.


How do I download Stack Overflow's data?

I heard that Stack Overflow's Question/Answer data is downloadable.  How can I get it?


Windows Subsystem for Linux (WSL): X error of failed request: BadWindow (invalid window parameter)

I am using Windows Subsystem for Linux (WSL), and I have just installed xcrysden on it with no apparent problem, however when I try to run it, I repeatedly get the Following error:  X Error of failed request: BadWindow (invalid Window parameter)   Major opcode of failed request: 3   ResourceID in failed request: 0xffffffff   Serial number of failed request: 761   Now running graphical interfaces in WSL is a bit annoying. To do it, I use the  X server for Windows. I set the DISPLAY variable via export DISPLAY=localhost:0.0, and that does the trick for me. I can run for example gnuplot with no problem this way.  Why does xcrysden fail to launch in this situation?  Here is the full STDERR Stream that I get:  Running on platform : unix Operating system : Linux Package ImageMagick's convert: /usr/bin/convert Package ImageMagick's import: /usr/bin/import Package Ppmtompeg: /usr/bin/ppmtompeg Package Babel: /usr/bin/babel Executing: /usr/lib/xcrysden/ftnunit X Error of failed request: BadWindow (invalid Window parameter)     Major opcode of failed request: 3     ResourceID in failed request: 0xffffffff     Serial number of failed request: 759 X Error of failed request: BadWindow (invalid Window parameter)     Major opcode of failed request: 3     ResourceID in failed request: 0xffffffff     Serial number of failed request: 761 Error in startup script: Togl: couldn't get visual     while executing "togl .mesa -width 400 -height 400 -ident .mesa -rgba true -redsize 1 -greensize 1 -blu..."     (procedure "PlaceGlobWin" line 105)     invoked from within "PlaceGlobWin 0 [expr round(650 * $fac1)] [expr round(650 * $fac1)]"     (procedure "ViewMol" line 25)     invoked from within "ViewMol ."     invoked from within "if [file exists $filedir] {                 # pop-up Viewer                 ViewMol .                 openExtStruct 3 crystal external  [list sh $system(TOPDIR)/scripts/pwi2xsf.sh]  pwi2xsf..."     (procedure "parseComLinArg" line 89)     invoked from within "parseComLinArg [lrange $argv 2 end]" invoked from within "if { [llength $argv] > 2 } {     parseComLinArg [lrange $argv 2 end] } else {     ViewMol . }"     (file "/usr/share/xcrysden/Tcl/xcInit.tcl" line 609) X Error of failed request: BadWindow (invalid Window parameter)     Major opcode of failed request: 12     ResourceID in failed request: 0xffffffff     Serial number of failed request: 764


Whats the best way to round in VBA Access?  My current method utilizes the Excel method  Excel.WorksheetFunction.Round(...   But I am looking for a means that does not rely on Excel.


List of key value lists to dictionary of lists


what is the special case that make `str1 == str2` a logical error?

I know that java stores String Literals in Common Pool and two string literals having the same text will refer to the same place in Common Pool. take below code:  String str1 = "Amir"; String str2 = "Amir";   now both str1 and str2refer to the same place in the Common Pool. so from what all we know we must use equals() to properly compare these two strings and obviously str1.equals(str2) will be true.   now from what i read   it says that the str1 == str2 will be true becuase the strings both have the same address (sounds pretty logical) but it also states that its a logical error to do so.  my question is what is that special case that may cuase trouble and inconsistency to my code if I use str1 == str2 ?


After reaching 3000 reputation points, I've been alerted of the fact that I may vote to close posts with low level quality -- and other possible reasons.  Since that, every time I flag a post, the flag seems to be converted into a vote to close, with the respective reason -- the same used to flag.  After being able to vote to close posts, does one's flagging activity stops, being converted into close votes? If so, how come some people have so much reputation, and considerably high levels of flagging activity?


How and where, in the human brain, are memories stored?

Background I am a computer programmer who is fascinated by artificial intelligence and artificial neural networks, and I am becoming more curious about how biological neural networks work. Context & what I think I understand In digesting all I have been reading, I am beginning to understand that there are layers to neural networks.  A front-line layer of neurons may receive, for example, a visual stimulus such as a bright light.  That stimulus is taken in by the front-line neurons, each of which produce a weighted electro-chemical response that results in a binary decision to pass an electrical charge through its axon to the dendrites of the tens of thousands of neurons to which it is connected. This process repeats through layers channeling the electrical signals and focusing them based on their permutations until ultimately a charge is passed to a focused response mechanism such as the nerves that control shrinking of the pupils. Hopefully I got that correct. Preamble to the question ;) Assuming that I am not completely off-base with my basic understanding of how a biological neural network operates, I am beginning to grasp how an input (stimulus) results in an output (response) such as motor movement or reflexes.  That would just seem to be basic electricity of open and closed circuits. HOWEVER, what confuzzles me still is how a memory is stored.  The analogy to an electrical circuit breaks down here, for in a circuit I can't really stop the flow of electrons unless I dam up said electrons in a capacitor.  If I do that, once the electrons are released (accessed), they are gone forever whereas a memory endures. So. . . How the heck are memories constructed and stored in the human brain?  Are they stored in a specific region?  If so, where?


I didn't get the answer to this anywhere. What is the runtime complexity of a Regex match and substitution?  Edit: I work in python. But would like to know in general about most popular languages/tools (java, perl, sed).


How to create a .deb file with dependency?

I have a game made with the LÖVE framework and I want to package it into a .deb file so it can be easily installed by others and be easily findable through the Unity dash for example.   I also have the LÖVE framework love_0.7.2.deb which I want to be in the deb file also somehow.  Files that I have:  game_icon.png game .desktop the_game.love love_0.7.2.deb   Could someone explain to me how to do this?


How can we show that $$\sum_{n=1}^{+\infty} \frac{1}{n^n} = \int_0^1 \frac{1}{x^x}dx$$   Could you give me some hints??


How this close loop control systems work?

I have attached photo of a lecture where a slide is showing a close loop control system(theif repulsion system). But i am confused by the electric eye?how it is working?is the robber/theif so mad that he is carrying an IR source in his hand?(normally a theif is expected to have a pistol or knife in his hand)


"Thought of" vs. "thought about". What's the difference?

What's the difference between "thought of" and "thought about"? One difference I'm aware of is that you use "thought of" when something comes to mind but you don't analyze it, and "thought about" if you analyze it. Are there any other differences?


Realtek RTL8723be doesn't have good reception

Only when I'm closer to the router, it shows any signal, but when I'm just little far from it, it is not showing wifi routers signals.


When I try to remove the virtual box installed on ubuntu as follow,   sachin-verma@sachin-verma:~$ sudo apt-get remove virtualbox-5.1  Then it shows following errors:  Reading package lists... Error! N: Ignoring file '50unattended-upgrades.ucf-dist' in directory '/etc/apt/apt.conf.d/' as it has an invalid filename extension N: Ignoring file 'getdeb.list.bck' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension E: Encountered a section with no Package: header E: Problem with MergeList /var/lib/apt/lists/in.archive.ubuntu.com_ubuntu_dists_xenial_main_binary-amd64_Packages E: The package lists or status file could not be parsed or opened.   Please help me out ?  PS.- This is also happening, when I am trying to uninstall other packages.


Extension method not listed on GetMethods()

I've an extension method on DateTime:  public static DateTime? Year(this DateTime? datetime) {     return datetime; }   And antoher one which is trying to build a CallExpression to this extension method:  public static Expression<Func<TElementType, DateTime?>> SemanticYear<TElementType>(this Expression<Func<TElementType, DateTime?>> expr) {      MethodInfo method = typeof(DateTime?).GetMethods().Where(m => m.Name.Equals("Year"));     //<<<<<< returns null!!      Expression<Func<TElementType, DateTime?>> lambdaExpression = Expression.Lambda<Func<TElementType, DateTime?>>(         Expression.Call(             Expression.MakeMemberAccess(expr.Body, typeof(DateTime?).GetProperty("Value")),             method         ),         expr.Parameters     );      return lambdaExpression; }   Why do I unable to get DateTime?.Year extension method?  Both methods are implemented inside the same compilation unit:  namespace Backend.Infrastructure.Linq {     public static partial class LinqTreeExtensions     {          public static DateTime? Year(this DateTime datetime)         {         //....         }          public static Expression<Func<TElementType, DateTime?>> SemanticYear<TElementType>(this Expression<Func<TElementType, DateTime?>> expr)         {         //.......         }     } }


let ${v_1}, {v_2} $ be orthonormal basis for subspace $W$. Prove that if $z$ is a vector in $W$, then

let ${v_1}, {v_2} $ be an orthonormal basis for a subspace $W$. Prove that if $z$ is a vector in $W$, then $||z||^2 = (z \cdot {v_1})^2 + (z \cdot {v_2})^2$  I'm not too sure where to start on this one. I'm thinking I have to cancel out ${v_1}$ and ${v_2}$ since the dot product of two orthogonal vectors is zero. Any help is appreciated.


A finite extension with finitely many intermediate fields is simple

It is well-known that is $E$ is a simple finite extension over $F$, then it has finite many intermediate fields.   Actually Minle's notes says that if an finite extension has finite intermediate fields, then it is simple! I am curious about this fact, could someone give a proof? Thanks!


Knocked up, two very different meanings. But why and how did the phrase split?

In American English, "Knocked up" means "pregnant."  I just found out via an article regarding  that in British English, they use use the phrase "Knocked up in a completely differnt way.  This due to the job of knocker-uppers being the tapping or knocking on windows to awaken people in the days before alarm clocks.  From , it appears that the meanings split somewhere between the 1920s and the 1940s.    Does anyone know the history of how the meanings split and exactly why and how it happened?


In the movie we see       Starkiller Base fire upon and destroy five planets (or a mixture of 5 planets and moons) within a single solar-system.   This event appears to be observed simultaneously and instantaneously/in real-time by multiple characters from a variety of very different vantage points.  For instance:   Han, Rey, Finn, et al. from the surface of whatever world they're on (which as I understood it was still some distance away from Republic space). Leia and the other Republic commanders observe from their command center. The troops who fire the weapon appear able to observe its results.   My question is, what is the relative position of all of these vantage points that would allow simultaneous observation like that?  Even from a vantage point within the targeted system it would likely take minutes, at least, to observe the full effects of the weapon.  Was everyone actually in more-or-less the same place (or at least, equidistant from the target zone) when the weapon was fired?  Meaning the First Order was firing on a very nearby target (which would invite the question of why the Republic would allow such a massive and obvious superweapon to be constructed so close to their area of influence?)?  Or is this just a case of the movie not taking practical physics into account?


I hesitate to ask this question, but I read a lot of the career advice from MathOverflow and math.stackexchange, and I couldn't find anything similar.   Four years after the PhD, I am pretty sure that I am going to leave academia soon. I do enjoy teaching and research, but the alpha-maleness, massive egos and pressure to publish are really unappealing to me, and I have never felt that I had the mathematical power to prove interesting results. However, I am really having trouble thinking of anything else to do. Most people seem to think that the main careers open to mathematicians are in banking and finance. I really want to work in some field where I can use mathematics, but it is also important to me to feel like I am contributing something positive or at least not actively doing harm. For this reason, financial speculation is very unappealing to me, although I do find the underlying mathematics quite fascinating.  Here is my question: what careers which make a positive contribution to society might be open to academic mathematicians who want to change careers?


how to print ps header when using pipe in linux  this normal ps output  $ ps -ef UID         PID   PPID  C STIME TTY          TIME CMD root          1      0  0 17:00 ?        00:00:02 /usr/lib/systemd/systemd   but below ps command output without header  $ ps -ef | grep systemd root          1      0  0 17:00 ?        00:00:02 /usr/lib/systemd/systemd   how do i print ps header for second command?  thx


NullPointerException Error when calling fillTable()

I can not seem to spot where I get NullPointerException Error when call the method fillTable(). fillTable is called from the button what takes in String from a textField. fillTable is meant to populate a JTable by retrieving Object[][] containing data from a handler class.  private void fillTable(String dataType, String searchBy)     {         String[] columnName = {"module name", "Workshop %", "Lecture %", "Tutorial %", "Average %"};         if(searchBy.startsWith("@"))         {             tableModel.setDataVector(pLSHand.gIStudData(dataType, searchBy), columnName);             table.setModel(tableModel);         }         else         {             tableModel.setDataVector(pLSHand.gNStudData(dataType, searchBy), columnName);             table.setModel(tableModel);          }         table.repaint();     }   Button:  String searchBy = (String)textField.getText(); if(!searchBy.isEmpty()) {    fillTable("Year",searchBy); } else {  }   Method in the Handler class  public Object[][] gIStudData(String dType, String studID)     {          String rQuery = "SELECT * FROM StudAttYear WHERE studentID = '"+ studID +"'";         data = new Object[1][5];          if(dType.equalsIgnoreCase("Semester"))         {             rQuery = "SELECT * FROM StudAttSem WHERE studentID = '"+ studID +"'";             data = new Object[2][5];         }         else if(dType.equalsIgnoreCase("Year"))         {             rQuery = "SELECT * FROM StudAttYear WHERE studentID = '"+ studID +"'";             data = new Object[1][5];         }         else if(dType.equalsIgnoreCase("Week"))         {             rQuery = "SELECT * FROM StudAttWeek WHERE studentID = '"+ studID +"' AND number = '"+ weekNo +"'";             data = new Object[12][5];         }          try{                Class.forName(DRIVER_CLASS);                  connection = DriverManager.getConnection( url,"agile", "adila");                 statement = connection.createStatement();                 results = statement.executeQuery(rQuery);                 int i=0;                 while(results.next())                 {                      data[i][0] = results.getString("module");                      data[i][1] = results.getString("workshop%");                      data[i][2] = results.getString("tutroial%");                      data[i][3] = results.getString("lecture%");                      data[i][4] = results.getString("avg%");                  i++;                 }            results.close();            statement.close();            connection.close();            } catch (SQLException sqlException) {            sqlException.printStackTrace();            System.exit(1);            }catch(Exception exception) {            System.err.println("An error happened");            System.exit(1);          }         return data;     }   Using the same technique in other classes and they seem to work.


Disassociated posts are still linked from the network profile

An anon user (which I assume stands for "anonymous")    doesn't seem to be very anonymous. This particular screen shot was taken from a  which I found by following a link on a (very non-anonymous) StackOverflow profile:    Ironically it's on security.SE regarding privacy.  If it's really intended behavior that the post should be listed among the users Top Network Posts, I think it should somehow be clarified that the user is not in fact anonymous.


Finding institutions that attract students who want to learn

Among institutions that will be hiring professors of mathematics, how can one identify those which attract students that want to learn? When looking for a job, how can you identify institutions whose values / mindset / pedagogy suit you best? How to find an institution where it would be normal for students to show up for the material in the course, rather than treating it as a price they pay to get a grade?


How to get intuitive understanding of common fundamental distributions

(I have asked  in the math site, but think it might be more relevant here) I have been following the online MIT statistics course, and one course was about some fundamental distributions.()  I read it a couple of times and did a lot of search online, but I still find it hard to fully grasp the idea of how to match different distributions to different real life scenarios.   For example, "Suppose we have a tape measure with markings at each millimeter. If we measure (to the nearest marking) the length of items that are roughly a meter long, the rounding error will uniformly distributed between -0.5 and 0.5 millimeters." I just cannot wrap my head around how it was determined that uniform distribution matches this case.  I'm wondering if there are some books/articles that give detailed and intuitive explanation of distributions and their real life applications?


When I create the pdf all I obtain is a frame with the name of the image instead of the image itself. Here’s the code I’m using :   \documentclass[11pt,a4paper,draft]{article}   %Packages importants>>>>>>>>> \usepackage[utf8]{inputenc}                  \usepackage[francais]{babel}                 \usepackage{amsmath}                         \usepackage{amsfonts}                        \usepackage{amssymb} \usepackage{mathtools} \usepackage{lipsum}                          \usepackage[pdftex]{graphicx}                        \graphicspath{{C:/Users/dad/Desktop/projet_recherche}} \begin{document}     \lipsum[1]     \includegraphics[scale=0.25]{car}\\     \lipsum[2] \end{document}     Is there something I should omit or add?


I have one div of class 'outerpiccontainer' which contains another div 'pic container' inside of it. The inner div is currently empty and just has some styling applied to it, it is 80% height and width of the outer div.  Currently I am able to center the inner div by using a left margin of 10% (10+10+80 =100). However I am not happy with this solution (if I change the size ratio between divs I will lose my center). Is there a way or property to center a div within a div?  Thanks in advance! I have the html portion followed by css below.

Place photo here

  .outerpiccontainer  {     background-color:#BF1432;     width:38%;     height:400px;     padding:1%;     border-top:5px inset #DCDCDC;     border-bottom:5px inset #DCDCDC;     border-bottom-left-radius: 8%;     float:left }  .piccontainer  {     background-color:#DCDCDC;     width:80%;     height:80%;     padding:1%;     border-radius: 50%;    -moz-box-shadow: 10px 10px 5px black;    -webkit-box-shadow: 10px 10px 5px black;     box-shadow: 10px 10px 5px black;     margin-left: 10%;     float:left;  }


How to convert an array into an ArrayList?

I have an array that is initialized like this:  Element[] array = {new Element(1), new Element(2), new Element(3)};   How do I to convert this array into an ArrayList object?


How can the Neutral wire be 0V if its AC?

So I understand Alternating current like a battery, in which the Poles are constantly changed out, so the circuit stays completed, but the electrons change directions. But how can then in an AC plug one wire (neutral) always be 0V? The electrons always move from positive to negative right? If I´d be right the neutral wire had to be "+" 25/30 times a second, but that can't be possible if neutral alsways is at 0V.  Please explain, so an electronics noob could unterstand it :D


SQL Server - Is there a way to query the specific Size and Space available settings for each Database, including system databases on an instance?

I am trying to query the two default database properties as seen in the picture below for all databases on an instance, including system databases. I've used various scripts such as the following, but I'm not sure exactly where data for those two fields are stored. SELECT        database_name = DB_NAME(database_id)     , log_size_mb = CAST(SUM(CASE WHEN type_desc = 'LOG' THEN size END) * 8. / 1024 AS DECIMAL(8,2))     , row_size_mb = CAST(SUM(CASE WHEN type_desc = 'ROWS' THEN size END) * 8. / 1024 AS DECIMAL(8,2))     , total_size_mb = CAST(SUM(size) * 8. / 1024 AS DECIMAL(8,2)) FROM sys.master_files WITH(NOWAIT) WHERE database_id = DB_ID() -- for current db  GROUP BY database_id   Thank you for your help.


What is the process for a moderator to request reinstatement or appeal a removal?

Please leave any feedback or questions about this process on .   From time to time, moderators will step down or be removed from their positions — they may have expressed their wish to step down due to time constraints or they may have had behaviors unfitting of a moderator and have been forcefully removed, along with a number of other possibilities that fall somewhere between those two. What is the process for evaluating moderator reinstatement or removal appeal requests?  Note: Feedback on the original version of this post can still be found .


Security Reasons to upgrade from Windows XP Needed

Is there a white paper, or any long winded sob story already written why we desperately need to stop using Windows XP and upgrade to... well, anything other than XP really, 7/8/10. ?  I've searched, and you would have though Microsoft would be spamming the internet with reasons to upgrade, but I've come up with nothing, was/is it really that loved?  anyway, I really do need some sound reasons to get rid (I personally want to get rid due because of the limited memory support, can't use latest .Net framework and can't use latest SQL Express, but if I had a sound security reason.. well people would panic into upgrading right?)


I want to prove that $ e^x \ge 1+x $ for all $ x \in R $ , using Mean Value Theorem it can be proved for $ x \gt 0 $, and equality holds for $ x = 0$, however I can't solve it for $ x \lt 0 $


I am running Ubuntu 12.04 LTS.  I have downloaded several programs (, , ) and they all come in ZIP format. Once I uncompress them I can use them, but I cannot access them via the Dash Home Menu, like I explain in this thread:      In that thread the answer was in creating a XXX.desktop file, populate it with random fields, and then move that file to a specific folder.   I now want to do the same for my Eclipe and SmartGit programs (as well as to any other programs I may end up using) so now I believe I need to learn how to create an XXX.desktop file with the correct fields and the correct instructions.   Where can I find the information to do that?


How to suppress indentation of first paragraph after heading?

I am writing a document in a class (elsarticle) that indents the first lines of all paragraphs, including the ones following headings.  However, I would like to revert back to the default Latex behavior indenting all but the first paragraphs.  Of course I can do this manually using \noindent, but isn't there a better way?


I've been using the  in R to build predictive models for classification and regression.  Caret provides a unified interface to tune model hyper-parameters by cross validation or boot strapping.  For example, if you are building a simple 'nearest neighbors' model for classification, how many neighbors should you use?  2? 10? 100? Caret helps you answer this question by re-sampling your data, trying different parameters, and then aggregating the results to decide which yield the best predictive accuracy.  I like this approach because it is provides a robust methodology for choosing model hyper-parameters, and once you've chosen the final hyper-parameters it provides a cross-validated estimate of how 'good' the model is, using accuracy for classification models and RMSE for regression models.  I now have some time-series data that I want to build a regression model for, probably using a random forest. What is a good technique to assess the predictive accuracy of my model, given the nature of the data? If random forests don't really apply to time series data, what's the best way to build an accurate ensemble model for time series analysis?


For $A$ any subset of vector space $X$, is it true that $A+A=2A$?

It seems a trivial question:  Prove/disprove: If we have a vector space $X$, then for any subset $A$ of $X$, we have $A+A =2A$.  It seems that $2A$ is always subset of $A+A$, but I don't think $A+A$ is subset of $2A$. I am thinking in set of integers modulo $p$, for $p$ a prime, as a counterexample. Am I right?


Using directional shading on boundaries for cartographic effect in ArcGIS Desktop?

The attached screenshot of a National Geographic map shows some beautiful directional shading of boundaries.  I'm trying to reproduce this sort of shading for a burn perimeter map, as I want to highlight features within the burn perimeter and not overshadow them with a transparent polygon or crosshatch.  Is there a way to accomplish this sort of boundary shading using ArcGIS 10?  Link to  titled: "1946 Political Subdivisions Of India By National Geographic.jpg"


Can FIFA be played cross-console online?

My friend has a Xbox one, while I've got an Xbox 360.  Will I be able to play FIFA 16 with him online? Or would I have to get an Xbox One to play with him?


Can anyone explain why this comparison return true in ruby?

I wrote this in rails console   (3352.3744333333334==3352.3744333333335) #true  and result was true  Notes:  I'm using ruby 2.4.0 and rails 5.0.1


Login screen not appearing after removing KDE

I've been using Ubuntu 13.10 for about a month now. I decided to give KDE a test run. Unfortunately, it installed the KDE login screen with it. I couldn't stand it, so I spent about half an hour trying to restore the original one.  Nothing worked, until I went in through Synaptic and removed most KDE packages installed. Bad idea. Now, when I boot the computer, I am greeted with a black screen. And by that, I mean the screen has turned off completely. I am able to navigate to a virtual terminal using CTRL+ALT+F1. Here's the interesting thing; When I go to TTY7, Plymouth is still running. I go to TTY8, and my screen turns off again.  Is there a way I can fix this and get the old login screen back, or is it time to start the preparations for a re-installation? Thanks!


Is there a word or phrase that expresses the feeling of nervous anticipation as you wait for the result of something, whose outcome you cannot control and could be either good or bad?


Prove that $0!+1! + 2! + 3! + ..... + n!$ $\neq$ $p^\text{r}$, where $n \geqslant 3$ and $n$, $p$ and $r$ are three integers

Let $n$, $p$ and  $r$ be three positive integers. Prove that for $n \geqslant 3, r>1$, $$\sum_{k = 0}^{n} k! \neq p^\text{r}$$   SOURCE: BANGLADESH MATH OLYMPIAD (Preaparatory Question)  I am not so familiar with such a this kind of problem. Seeing that problem, I became little bit curious about what the text states and what will be its conception?   I couldn't solve the problem. Moreover, I don't know about the formula of $\sum k!$. Is there any? And I couldn't realize the essence of $p^\text{r}$ and what the reason is behind the fact the summation can't be equal to $p^r$ for some integer $p$.  Any kind of reference or conception will massively help me start with some approach to solve the above problem. Thanks for your support and effort in advance.


$P_n[0,1]$ be the set of all polynomial of degree atmost $n$ with supnorm is it a closed in $C[0,1]$? and $P[0,1]$ is set of all polynomials in $C[0,1]$  I know which is dense in $C[0,1]$ as we know by Weirstrass Polynomial approximation theorem any continous function can be uniformly approximated by sequence of polynomials.   Thank you for  help.


Confidence intervals for the probabilities of each outcome in a multinomial

I have a survey that includes questions where you can choose one option from a list. For example: "How often do you go to the supermarket?" A. Every day B. 2-6 times per week C. Once per week or less D. Never  Say 1000 people respond to the survey and 100 people choose option A, 400 option B, 400 option C and 100 option D. How do you calculate the confidence intervals of these proportions? Are they simply binomial confidence intervals (i.e. just normal proportions)? Or is it something more complicated, because the proportions are related to each other?


"Сделать на отъебись" in English

There's an obscene yet often used expression in Russian which sounds exactly like this: "Сделать что-то на отъебись" Which means you do/create/complete something just enough so that it worked (often in a very bad, barely sufficient, shoddy way) and not a single bit more. As a result of such "work", the product can be used for its primary purpose but it leaves a very bad aftertaste and in certain cases can even be dangerous. Is there a similar expression in English? A literal translation would be "To do something [so that you or someone else] fucked off".


Consider the following lines   $x-y-1=0$ $x+y-5=0$ $y=4$   The line 1 is the axis of the parabola, the line 2 is the tangent at the vertex to the same parabola, and the line 3 is another tangent to the same parabola at some point $P$.  Now let a circle $C$ circumscribing the triangle formed by tangent and normal at the point $P$ and the axis of the parabola.  Then how can I find the equation of the circle?  I have tried and found that the vertex of this parabola is (3,2). Need help....don't know how to proceed further.... Thanks in advance...


i need to write data into a CSV file each 600 msec using a c# application . The question: is better open and close file each time or keep it open until the end of write data actions? Note: i will change file name each day and each 60000 record  Thanck a lot for your opinions


Check for missing fonts/characters in XeLaTeX?

Because I began to use many Unicode characters (Japanese, some unusual diacritics, etc.) I switched from LaTeX to XeLaTeX to render my documents. Unfortunately, if a font is missing, the letters are simply left out (for example, when I had forgotten to specify the font for Japanese) without any error (and I can't seem to spot a warning either). I will read the result, but I prefer to get some early warning if some character isn't available. Is there any way to get a warning about characters that have not been rendered? An error would be even better.


Checking understanding of summations of divergent series

I recently learned about various techniques for summing divergent series. These techniques make it possible to show that, for example, $$1 + 2 + 3 + 4 + 5 + ... = \frac{-1}{12}.$$  I am a bit confused because the summation $1 + 2 + 3 + 4 + 5 + ...$ diverges under the definition of infinite summations I'm used to (namely, as a limit of the finite summations) but still seems to work out to a number using these other techniques. I'm trying to determine how to reconcile these disparate pieces of information together.  Right now, I have two different hypotheses about how to understand these results together simultaneously:   There are two different definitions of what an infinite summation "means." One uses limits of finite summations, and the other uses complex analysis. Since these definitions aren't identical to one another, it's not surprising that they predict different results in this case, and the disparity arises because there are two different definitions that happen to use similar notation to describe their results. Just because the partial sums of the first 0, 1, 2, 3, 4, 5, ... etc. terms of the series don't converge to a value doesn't mean that the sum of all infinitely many terms doesn't have a value. The series diverges because the finite partial sums don't converge to anything, but the infinite summation really is indeed $\frac{-1}{12}$.   Are either of these hypotheses correct? Or am I off-base here? I'm hoping to learn how to think about results like these, and if there's some bigger picture that everything fits into I'd appreciate more information about it.  Thanks so much!


Does there exist a matrix $P$ such that $P^n=M$ for a special matrix $M$?

Consider the matrix $$ M=\left(\begin{matrix} 0&0&0&1\\ 0&0&0&0\\ 0&0&0&0\\ 0&0&0&0\\ \end{matrix}\right). $$ Is there a matrix $P\in{\Bbb C}^{4\times 4}$ such that $P^n=M$ for some $n>1$?    One obvious fact is that if such $P$ exists, then $P$ must be nilpotent. However, I have no idea how to deal with this problem. Furthermore, what if $M$ is an arbitrary nilpotent matrix with index $k$?


Typedef using templated nested class within a templated class

So I have SkipList.hpp which has a nested templated class called SkipListIterator.  //SkipList.hpp template <class Key_t, class Mapped_t> class SkipList {     template <bool isConst, bool isReverse>     class SkipListIterator {         ...     }     ... }   In my Map.hpp, I want to make typedefs for the different types of iterators. What I tried to do was the following:  //Map.hpp  #include "SkipList.hpp" template <class Key_t, class Mapped_t> class Map {     typedef typename SkipList<Key_t, Mapped_t>::SkipListIterator<false, false> iterator;     typedef typename SkipList<Key_t, Mapped_t>::SkipListIterator<true, false> const_iterator;     typedef typename SkipList<Key_t, Mapped_t>::SkipListIterator<false, true> reverse_iterator;     typedef typename SkipList<Key_t, Mapped_t>::SkipListIterator<true, true> const_reverse_iterator;     ... }   This does not work, and g++ gives me the following error:  error: non-template 'SkipListIterator' used as template typedef typename SkipList<Key_t, Mapped_t>::SkipListIterator<false, false> iterator                                             ^


Can a light be bent by a magnetic field?

I'm struck with two competing ideas on the question in the title.  :   How far can a magnetic field bend light?   A: Unfortunately, the path light takes is not affected by the presence of a magnetic field. Light itself is composed of an oscillating electric and magnetic field, and one very important property of electric and magnetic fields is what we call linearity. That is, if you have two sources of electric and/or magnetic fields, you can predict what the combined field is just by adding the two source fields together. The two fields don’t change each other at all.   (Answer #1)    Does electric charge affect the space time fabric? If so, why?    A: [See link. Rather, see both links if you must.]  I'm more inclined to consider the latter question and answer as the correct interpretation. Anyway, if anyone could help me out with this conceptualization that would be great, thanks.


Is there a way to "fix" my stainless steel fry pan that does not sit flush on my cooktop stove?


Test convergence of series: $$\sum_{n=0}^ \infty n!z^n$$  What I have done using ratio test:  $\lim_{n\to\infty} \lvert \frac{(n+1!)(z^{n+1})}{n!z^n}\rvert$  $\lim_{n\to\infty} \lvert (n+1)(z)\rvert$  And here I am kinda stuck. Do I plug in $\infty$ for n and get $\infty$ as the answer?  If $L=\infty$ then it diverges since $L>1$?


If $\lim_{x\to c}f'(x)=A$ then $f'(c)=A$

I have problems with this exercise in the book Real Analysis of Miklós Laczkovich:  Let $f$ be continuous on $(a,b)$ and differentiable on $(a,b)\setminus \{c\}$, where $a<c<b$. Prove that if $\lim\limits_{x\to c}f'(x)=A$, where $A$ is finite. then $f$ is differentiable at $c$ and $f'(c)=A$  Since this problem is in the section of the mean value theorem, I have tried to attack it from that side, but I can not see what considerations to take to solve it, I would appreciate any help, thank you.


Assume we have a non empty, open convex set $ K \subseteq \mathbb{R}^d $. Then $\overline{K}$ is also convex. How can we prove that statement? I thought that breaking it into cases would help. If $x,y \in int(K)=K^o$ then from hypothesis the statement holds. If $x \in K^o $ and $y \in \partial K$ then from a theorem of my notes :P means $[x,y) \in K $. I have stacked how to show it with details that for each $x,y \in \overline{K}$ then $[x,y] \in \overline{K}$


How do I study the "correlation" between a continuous variable and a categorical variable?

What's a meaningful "correlation" measure to study the relation between the such two types of variables?  In R, how to do it?


What happens to the rotational kinetic energy?

There is a classic example that a spinning skater pulls his arms back. The angular momentum is conserved, the moment of inertia decreases. And therefore, it's angular velocity increases, so the rotational kinetic energy will increase. But what will happen if the skate pushes his arms outward? The rotational kinetic energy will decrease. But where will it go?


How to use python to group a list of numbers by ascending order?

Lets say I have this list of numbers:  1, 2, 3, 4, 7, 8, 10, 12, 15, 16, 17, 18, 19, 20, 21, 22, 24, 26, 27, 29  And I want to create 5 even groups based on ascending order in the list:  group 1: 1, 2, 3, 4, 7  group 2: 8, 10, 12, 15, 16  group 3: 17, 18, 19, 20, 21  etc...  Can I use python to do this?   I know that I can group by 0:4; 5:9... but I have many lists of various lengths that I need to sort into 5 exact groups each.


Gauss Law Question. Could anyone explain to me why does S3 is 0 in this lecture note example?

Why does S3 equal to 0 ? for E3 dot dA = 0?  Could I also know why does dA1 and dA2 point up and down? while dA3 point to the right?


We learned in class about the Cauchy–Schwarz inequality. Can some one please  give me a geometric intuition or any intuition in general for why this inequality is true? Thank you.


Primitive values (int) in Tries while doing DFS

I m trying to calculate the value of prefixCount in Trie, as below.  I am puzzled why the value of count is not returned as 3  Just in case , Tries contains [by,bye, byer, rat]. Why count is return as 0, and not 3.  public int prefixCount(String prefix) {     int count = 0;     TrieNode node = searchPrefix(prefix);     if(node != null)     {         prefixCount(prefix, node, count);     }     return count; }  public void prefixCount(String prefix, TrieNode node, int count) {     if(node.isEnd())     {         count++;     }      for(int index = 0;index < 26;index++)     {         char value = (char) (index + 'a');         TrieNode next = node.get(value);         if(next != null)         {             prefixCount(prefix + value, next, count);         }     } }   Am i doing something wrong while doing DFS operation.  Thanks !


Supermassive Black holes at centers of galaxies

Why there is super-massive black holes at the center of our galaxy and other galaxies ?


Is adjusting white balance before and after taking the photo same?

There is an option in my phone camera to adjust the white balance before taking photo. Again after taking the photo I can adjust it in any photo editing app. Do these two produce the same thing? I also want to know the answer in general for other options like adjusting the contrast, exposure etc.


When I have a public class, what is the access modifier for methods?

Lets say I have a class called Dog. It's a public class. I don't have any access modifier before the bark method. Is that bark method public, default, or something else? Where can I access that method from? I'm assuming only from the object instantiated from the Dog class, but couldn't hurt to ask. Thanks!     public class Dog {     private String name;     private String breed;      //Constructor     Dog(String name, String breed)     {         this.name = name;         this.breed = breed;     }      void bark()     {         System.out.println("ROOF!");     }      String getName()     {         return name;     }      String getBreed()     {         return breed;     } }


What is the difference between edits and revisions?

I notice that for the badge Strunk and White I need to have Edited 80 posts.  I can also see in my Activity that I've made 329 revisions.  I don't currently have the Strunk and White badge which got me wondering, What is the difference between the number of revisions I've made, and the number of posts I've edited?  Is it that my 329 revisions weren't accross 80 posts? (I haven't checked this to be sure but I will)


When I open task scheduler in windows 7 it gives an error saying:    The selected task "{0}" no longer exists. To see the current tasks click refresh.   Then another error comes like this:      Task scheduler service is not available.Task scheduler will attempt to reconnect to it. Then task scheduler shows nothing like this:


In my initial basic tests it is perfectly safe to do so.  However, it has struck me that attempting to manipulate this later in a function that deletes this could be a runtime error.  Is this true, and is it normally safe to delete this? or are there only certain cases wherein it is safe?


Why are some faces darker than others in edit mode?

Everything else is fine, it's not ngon or something, it's a quad, so why does this happens?


Recently I am worried about the functionality of my Pentax K-50, i.e. I am not able anymore to get real sharp images. Thus my question arose, what I should see as "sharp". So I took several pictures of a non-moving object (my alarm clock) and zoomed in at the focus point. But even there not everything is sharp when I get real close. Why? Should I check my camera, or is this normal? In the example picture, the focus point is exactly between the buttons in the middle.


Top right icons messed up Ubuntu 13.04 64bit

First time posting a question here so if I fail, please excuse me and of course notify me about my mistake.  My situation is that currently I'm on holiday in Spain and I installed Ubuntu 13.04 alongside my Windows 8 install.  Both are 64 bit and my Ubuntu also has 32bit libs installed for convenience and running programs like XAMPP for Linux etc.  So my issue is not really big or very interesting but it bugs me...  When I first logged in, all the icons in the top right (e.g. login / WiFi / Ubuntu One / sound / power) were all nicely lined up how they are supposed to be.  HOWEVER the second time I logged in... the Power icon was somewhere in-between.    I am not an experienced Linux user but I do use it for speed and ease of use (hence Ubuntu) and I know my way a little with the sudoing but nothing special.  The only thing I really want is the power button most right.  However, I have no clue how to fix this.  Any help would be much appreciated and sorry for the probably 'stupid' question.


Prove that $11,111,111.....$ is not a perfect square

I know there are many other same related questions, but as my profile says I don't have a mentor, I just wanted you guys to check my solution. First I noticed that, $11$ = $10 + 1$, $111$ = $10^2+10+1$, Similarly, $\underbrace{111\cdots111}_{n\,\text{times}}$ = $10^{n-1}+10^{n-2}+...+10+1$, which  can easily be evaluated as it is a finite geometric series. $$\sum_{i=0}^{n-1} 10^i=\frac{10^n-1}{9}$$ for $n \ge 2$. After this, I checked perfect square modulo $4$, Let $j$ be any integer, then if $j$ is even, then $j=2k \Rightarrow j^2 = 4k^2 \equiv 0 \mod 4$ and if $j$ is odd then, $j = 2k+1 \Rightarrow j^2 = 4k^2+4k+1 \equiv 1 (\mod4)$ Then, Since $\underbrace{111\cdots111}_{n\,\text{times}} = \frac{10^n-1}{9} \Rightarrow (9) (\underbrace{111\cdots111}_{n\,\text{times}}) = {10^n-1}$ $\equiv$ $2^n-1$ $(\mod 4)$ $\Rightarrow (\underbrace{111\cdots111}_{n\,\text{times}}) \equiv 2^n-1 \mod 4$ Since for $n \ge 2, 2^n$ is always a multiple of $4$. Hence, $\Rightarrow (\underbrace{111\cdots111}_{n\,\text{times}}) \equiv -1 \mod 4$ $\Rightarrow (\underbrace{111\cdots111}_{n\,\text{times}}) \equiv 3\mod 4$ But a perfect square leaves remainder $0$ if it is even and $1$ if it is odd. So, clearly for $n \ge 2,$  $(\underbrace{111\cdots111}_{n\,\text{times}})$ is not a perfect square. I know there are other questions related to this but I just wanted to verify if my solution was correct. Thank you and suggestions would be appreciated!


Proof by Lewis Carroll that an urn cannot contain two balls

I am self-learning probability theory and solving some problems from the book Probability and Random processes by Grimmett and Stirzaker. Exercise 1.4.4 poses a nice problem. I would like someone to verify, if my solution is correct and thought process is correct.  What do you think of the following 'proof' by Lewis Carroll that an urn cannot contain two balls of the same color? Suppose that the urn contains two balls, each of which is either black or white. In the obvious notation $P(BB)=P(BW)=P(WB)=P(WW)=\frac{1}{4}$. We add a black ball, so that $P(BBB)=P(BBW)=P(BWB)=P(BWW)=\frac{1}{4}$. Next, we pick a ball at random, the chance that the ball is black is (using conditional probabilities)  $$1 \cdot \frac{1}{4}+\frac{2}{3}\cdot \frac{1}{4} + \frac{2}{3}\cdot \frac{1}{4} + \frac{1}{3}\cdot \frac{1}{4}=\frac{2}{3}$$ However, if there is a probability $\frac{2}{3}$ that a ball, chosen randomly from three, is black, then there must be two black and one white, which is to say that originally there was one black and one white ball in the urn. Solution. I think, the fallacy in this proof has to do with mistaking the unconditional probability $P(BBB)$ for the conditional probabilities $P(BBB|\text{atleast one ball is black})=\frac{1}{4}$. \begin{align*} P(\text{Ball drawn at random is black}) = 1\cdot\frac{1}{8} + \frac{3}{8}\cdot\frac{2}{3} + \frac{3}{8}\cdot \frac{1}{3} + \frac{1}{8}\cdot 0 = \frac{1}{2} \end{align*} This makes perfect intuitive sense, because without any knowledge of what ball was added to the urn, the unconditional probability that a ball drawn at random is black is simply $\frac{1}{2}$; the ball is equally likely to be black or white. Surely, the urn can have two balls of the same color! I'm not sure, how to argue this. But, what I can tell for sure is, \begin{align*} P(BBB|\text{atleast one ball is black}) = P(BWW |\text{atleast one ball is black})= \frac{1}{4} \end{align*}


How to calculate $\lim_{x \to 0}\frac{\sqrt[3]{\cos x}-\sqrt{\cos x}}{x^2}$

I found this exercise in my math book but there's no step by step solution for solving this without L'hospital rule. I have no idea how to start.   $$\lim_{x \to 0}\frac{\sqrt[3]{\cos x}-\sqrt{\cos x}}{x^2}$$


Transfer MCPE World from iPad to iPhone on creative during LAN party

I was able to be on the world on both devices, but when I went into the pause menu on the iPhone that I wanted to "quit and copy world" to, the pause menu only had the typical "back to game", "options", and "quit to title" in the pause menu, not a "quit and copy world".  Thanks for any help!


What meaning has "the" article in "the more" usage?

Some examples with "the more":  But some of those kids can hardly read or write! All the more reason why they should get the best education on offer. The more is the better. (But that example is comparative correlative construction. It's somehow understandable case).  What's the meaning of this article? What's the difference between "the more" and just "more" ? And why is the article used without a noun?


Is it possible to prevent a Displacement modifier from affecting certain parts of a mesh?

A Displacement modifier is doing a great job making a mesh look a realistic object, but there are certain spots, such as a dozen or so vertices at one corner of the mesh, where I don't want any displacement effect.  The displacment is making a mess of things in those spots.  I don't want to undo my brilliant sculpting work there and re-do it after applying the modifier, or to fix the mess afterward. In fact, I don't want to apply the modifier.  Never mind my particular reason, since other Blender modelers may have the same question and want to animate, adjust the Displacment settings later, copy the object but have different ripples in the objects (using global coords), or whatever.  What would be nice is a way to modulate the "strength" setting with a grayscale image or painting in a UV map, but I'm not seeing how to do that.  I'm one of: unlucky at Google today, stupid, or ignorant of some non-obvious feature in Blender.  Maybe there's a nodes editor way to build a processing pipeline for modifier parameters?


Prove that the difference between two rational numbers is rational

This is a terribly simple question I'm sure, but I can't find a work-around in my proof. I must prove that the difference between two rational numbers is thus rational. Here is my attempt:     Let $a$ and $b$ be rational numbers. Therefore, \begin{align}  a=\frac{\lambda}{\beta},\:b=\frac{\xi}{\zeta},\:\ni\:\lambda,\beta,\xi,\zeta\in\mathbb{Z},\tag{1} \end{align} which gives us \begin{align}  a-b=\frac{\lambda}{\beta}-\frac{\xi}{\zeta}=\frac{\lambda\zeta-\xi\beta}{\beta\xi}.\tag{2} \end{align}   So I have shown that $a$ and $b$ are rational numbers which, by definition, can be represented by the quotient of two integers. But now how do I tackle the problem of the difference? By definition the difference between two integers is an integer. Does that require that this difference is thus rational?  Thank you for your time,


How do I enable or disable the global application menu?

I'm fairly excited for Unity, as it looks like a promising new direction for Ubuntu.  However, I do have a concern - will it be possible to use Unity without the global menu?  I have my window manager set to focus-follows-mouse/sloppy focus, and find the productivity gains to be immense. Sloppy focus is incompatible, however, with global menus, as it is possible for the focus to change while you move from window to menu.  Will Unity support an option to use window menus while still using Unity?


Need a simple buzzer/LED circuit for espresso machine

I have an espresso machine that I tore down, reassembled with fewer components then modified it to fit a specific setup -- kind of DIY project.   The machine has an autofill circuit. After I removed the controller and SSR, the machine does not have an autofill circuit, which is fine when I turn on the pump to refill manually. The only problem is checking the water level to find out when I need to refill the boiler. I fitted a sight glass for that purpose, but I still need another aid to notify me whether the water level is OK or not, mainly in case someone else is using it.   I want to add  a small buzzer/LED which is activated only when the water level drops below a certain point, OR just a LED which lights up so long as the water level is fine.   There is a water level probe. The boiler is grounded so if there is water touching it there will be a circuit/current through the probe, and if water is below the tip then there is no circuit (this is my understanding, so please correct me if it is not correct.)  There are buzzer/LED gadgets that can be bought cheap, but I want to know how it would work with the water level probe? I tried connecting the probe to a LED then  to one of electric current poles; I thought it should light up when there is water touching the probe, but it does not seem to work, or maybe it is just the wrong way to do it. :)   Any help is appreciated.


Using template for a function inside a namespace in a header

I am fairly new to C++ and I was experimenting with headers, this may be a simple problem but I couldn't figure it out.  I want to define a function that takes type T argument in header file then call it from main but the code does not compile.  I am using Visual Studio, Microsoft Visual C++ 2019.  //Header1.h #pragma once  namespace sout {     template <typename T>     void Print(T); }   //Header1.cpp #include <iostream> #include "Header1.h"  template <typename T> void sout::Print(T t) {     std::cout << t << std::endl; }   //Main.cpp #include <iostream> #include "Header1.h"  int main() {     sout::Print("dsa");      return 0; }   Main.obj : error LNK2019: unresolved external symbol "void __cdecl sout::Print<char const *>(char const *)" (??$Print@PBD@sout@@YAXPBD@Z) referenced in function _main   I solved like this below;  //Header1.h #pragma once #include <iostream>  namespace sout {     template <typename T>     void Print(T t) {         std::cout << t << std::endl;     } }   //Header1.cpp #include <iostream> #include "Header1.h"  template typename void sout::Print<const char*>(const char* t); template typename void sout::Print<int>(int t); template typename void sout::Print<double>(double t); template typename void sout::Print<float>(float t);   //Main.cpp #include <iostream> #include "Header1.h"  int main() {     sout::Print("dsa");     sout::Print(5);     sout::Print(5.5);     sout::Print(5.3f);      return 0; }


For the non-negative real numbers $a, b, c$ prove that $$(a^2+2)(b^2+2)(c^2+2)\geq 3(a+b+c)^2$$   What I did is applying Holder's inequality in LHS:$$(a^2+(\sqrt{2})^2)(b^2+(\sqrt{2})^2)(c^2+(\sqrt{2})^2) \geq (abc + 2\sqrt{2})^2$$   Then it suffices to prove that $$(abc+2\sqrt2)^2 \geq 3(a+b+c)^2 \\ \Rightarrow abc+2\sqrt2 \geq \sqrt3(a+b+c)$$   But I don't know how to proceed. I also think I applied Holder's Inequality incorrectly.


In a course I had, we have been given two statements P and Q and their "boolean table" :     While I completely understand P and Q and P or Q values, I can't understand the first two lines for P->Q, why is the result true even when P is false ?  Thank you.


Vertically center text in tabularx table

How to center text vertically in this table?  \begin{center}   \begin{tabularx}{\linewidth}{ | c | X | X | }     \hline       \textbf{Date} & \textbf{Name} & \textbf{Sign} \\     \hline       31.03.2013 & & \\     \hline   \end{tabularx} \end{center}   Changing package is not a solution for me. How to do it in tabularx?


Two physical web servers on port 80 behind a router

Current scenario  I have an Apache server running on default port 80 on a CentOS 6.7 box.  I forward port 80 from my router to this machine, and I can access it from the outside with my domain a.com.  Everything works as expected.  What I want to do  I stood up a second machine, CentOS 7, to act as a dedicated  server.  By default, it runs the web interface through nginx on port 80. I want to be able to access it through my subdomain gitlab.a.com.    Is this possible to do?  And if so, am I on the right track thinking it can be done with some combination of using a virtual host and a reverse proxy in Apache?  I'd prefer both of them to run on 80 if possible and not use alternate ports.


Adding element to list deletes previous elements

i have a class with a constructor that returns objects. I'm adding these objects to a list but having trouble because every time i add a new element it replaces the previous ones with the current element that i am adding.  Here is the list and output:      Objects a = new Objects("test1");     Objects b = new Objects("test2");      List<Objects> c = new ArrayList();      c.add(a);     c.add(b);     System.out.println(c.get(0).getTest());     System.out.println(c.get(1).getTest());   Here is the output:  test2 test2   Here is the class creating/returning the objects:  public class Objects {     public static String test;      public Objects (String test)     {         this.test = test;     }        public String getTest()       {           return test;       } }


Throttle network bandwidth per application in Mac OS X

I notice that iTunes seems to suck up all my bandwidth and doesn’t play nice with other applications that use the web when it's downloading.  In fact, it doesn't even give itself enough bandwidth when browsing the iTunes Store while downloading large or many files (podcasts, TV shows, large apps, etc).  I'm not concerned with getting all my downloads as soon as possible, they're really low priority, and I'd rather not have to do this while I'm awake, but I can't hit the refresh button if I'm in bed and forgot it already.  Is there an application or tool via the Terminal to limit the download bandwidth that iTunes gets without also hindering web browsers or other applications?  FOSS/GPL software is preferable, but pay software might be acceptable too.


Recently I saw the local media (Romania) presenting a case that was initially considered COVID-19 positive and two subsequent tests led to negative results. As far as I know no official bothered to offer an explanation and I assume that this is expected in some cases (e.g. initial test was not done correctly).  Like any other tests, I expect to have an accuracy < 100% and I am wondering what that accuracy is for current tests.  I have read here about  and  shows how tests are done in China:     (..) the main way to test patients is using the Reverse Transcriptase   Polymerase Chain Reaction (RT-PCR) technique.    deals with RT-PCR accuracy, but I cannot understand its conclusions.  By accuracy I mean (total tests - false positives - false negatives) / total tests.  Is there any figure about the accuracy of COVID-19 tests?


I'm unsure if I am using the present perfect continuous correctly here

Let's say that I arrived in England one month ago, and I'm going to stay two months longer. If someone asks me where I live, can I say "I've been living in England for one month" despite the fact that I'm going to stay a little bit longer?


Why could Harry and Lupin practice the patronus on the boggart?

In the Prisoner of Azkaban, Harry and Lupin could practice the patronus on the boggart, but when Harry was in the final task in the Goblet of Fire, he tried to use the patronus on the boggart, it didn't work and he then moved on to use ridikkilus.  Why could he use a patronus against the boggart, but then not in another?


Is a Whole Number part of A Rational Number or a whole number??


I know that $$\sum_{i=1}^ni=\frac{n(n+1)}{2}$$ can be proved using Gauss method , and  $$\sum_{i=1}^ni^2=\frac{(n^2+n)(2n+1)}{6}$$ can be proved using induction method,  what is the value of $$\sum_{i=1}^ni^m$$


Let $f: [a,b] \to \mathbb{R}$ be a differentiable function with continuous derivative. Prove the existence of $𝑀>0$ such that for all $x, y\in[a, b]$ the inequality |𝑓(𝑥)−𝑓(𝑦)|≤ 𝑀|𝑥−𝑦| is true. I was thinking of proving this using the Mean Value Theorem but I am not really sure how to proceed. Any help is appreciated.


How do I check the up time in Ubuntu 12.10?

Possible Duplicate:          Well sometimes for testing purposes I want to know the up time but don't know where to look. How do I check for this?


Here is a sentence in which I've used 'that' and 'which' with plurals (apples)     I have twenty apples which/that aren't mine.   Is it equally correct in grammar to use "which are" and "that are" with plurals (for example: apples)? Do they (that are and which are) convey the same meaning?


Lightning Component: Why component.find() does not find a dynamically created component?

SIMPLIFIED EXAMPLE   I want to find the dynamically created component "test2":  Markup  <aura:component access="global"       implements="flexipage:availableForAllPageTypes,force:hasRecordId,force:hasSObjectName"  >     <aura:handler name="init"           value="{!this}"                 action="{!c.init}" />     <ui:button label="Find" press="{!c.find}"/>     {!v.body}     <ui:button aura:id="test2" label="test2" /> </aura:component>   Controller  ({     init : function(cmp, evt, hlp) {             $A.createComponent(                 "ui:button", {                     "aura:id"       : "test1",                     "label"         : "test1",                 },                 function(newButton, status, errorMessage){                     if (status === "SUCCESS") {                         var body = cmp.get("v.body");                         body.push(newButton);                         cmp.set("v.body", body);                     }                  }             );      },     find : function(cmp, evt, hlp) {         console.log( 'but1' , cmp.find("test1") );         console.log( 'but2' , cmp.find("test2") );     }, })   Result      ORIGINAL EXAMPLE  I have a component using a   <ui:button label="Save" press="{!c.save}"/> <force:recordEdit aura:id="recordEdit1" recordId="{!v.itemId}" />   in it's markup. There this method to save:  save : function(cmp, evt, hlp) {     cmp.find("recordEdit1").get("e.recordSave").fire();     console.log( cmp.find("recordEdit1") ); },   Now when I'm when I remove force:recordEdit from the markup and create the force:recordEdit dynamically, all seems to work fine with this in the doInit():  $A.createComponent(        "force:recordEdit", {             "aura:id"       : "recordEdit1",             "recordId"      : cmp.get("v.itemId"),          },         function(newButton, status, errorMessage){                 if (status === "SUCCESS") {                     var body = cmp.get("v.body");                     body.push(newButton);                     cmp.set("v.body", body);                 }         } );    However in save() this line does not find the component anymore:  cmp.find("recordEdit1").get("e.recordSave").fire();   Why this?


I need to upload a file through "browse" button , but when I chose a file , it seems as "fakepath" . My test faces an issue. How can I deal with it?


How can i add a href button to an elseif statement

Im using this script in order to detect Metamask: if (typeof window.ethereum !== 'undefined') {     console.log('MetaMask is installed!');      const ethereumButton = document.querySelector('.enableEthereumButton');     const showAccount = document.querySelector('.showAccount');          ethereumButton.addEventListener('click', () => {       getAccount();   });      async function getAccount() {     const accounts = await ethereum.request({ method: 'eth_requestAccounts' });     const account = accounts[0];     showAccount.innerHTML = account;   }   }else{     const ethereumButton = document.querySelector('.enableEthereumButton').innerText = "InstallMetamask";   }  If metamask is not enabled, the user sees the else statement which shows a button on the UI saying "Install metamask" How can i add a link to this? What i want to achieve is when the users sees the button saying "install Metamask" i want the user to redirect to google chrome where he can install metamask. I tried to do ... .innerText = Install Metamask"  but of course i cant add html inside my script file like that. So how can i do this? and this is in my html file <button class="enableEthereumButton">Enable Ethereum</button>
Account:


Where can I find a large palette / set of contrasting colors for coloring many datasets on a plot?

I need large set (20 and more) of contrasted and easily visually-distinguishable colors for coloring different datasets on a scientific plot (the set of colors should not include white or black, and colors should be as bright as possible).   The plot is generated programmatically and intended to be included in a presentation which will be displayed using a projector.   Are there any ready-made sets of colors for such a task (I need colors as a set of RGB values)?   Or maybe there is some algorithm which generates such a set of colors programmatically (I use  for plot generation)?  P.S. The plot itself may look, for example, similar to this one:


I have output like so v12:     "owner" : "cs1372", v12:     "num-of-connections" : 1, v12:     "owner" : "cq5838", v5:     "owner" : "bb9886", v5:     "owner" : "aq0903", v5:     "owner" : "bj2468", v5:     "owner" : "di3080", v5:     "num-of-connections" : 1,  I need to return the line above the num-of-connections line. So what I want in this output is v12:     "owner" : "cs1372", v5:     "owner" : "di3080",  Is there an easy way to do this with sed or awk?


Number of elements of order $p$ is a multiple of $p-1$ (finite group).

This is a question in Pinter's A Book of Abstract Algebra.     Let $S=\{g\in G\mid \operatorname{ord}(g)=p\}$. Prove the order of $S$ is a multiple of $p-1$.   In his solution Pinter says $a \in S$ implies that $a$ generates a subgroup with $p-1$ elements. Shouldn't there be $p$ elements $\{1,a^1,\dots,a^{p-1}\}$? Or is it typical to only count the non-trivial elements in a subgroup?


How can we show that the following sequence converges?

$(a_n)$ is a bounded sequence with the following condition  $a_{n+1}\geq a_n-\frac{1}{2^n}$   The sequence converges, but how do we show it?


I have two C files 9.c ,10.c.  9.c  #include <stdio.h> int b=6; int main() { fun1(); printf("%d\n",b); } extern int b;   10.c   void fun1() { printf("%d\n",b); b=8; }   I did gcc 9.c 10.c but it gives following error:   10.c:3: error: 'b' undeclared (first use in this function)  I was expecting that linker would resolve the definition of b, but why its not resolving.


How can something happen when time does not exist?

I saw  hosted by Stephen Hawkins.  And if I didn't get it wrong, it says that there was no time before the big bang, time was created there.  So how can anything happen when there is no time (eg: the creation of time and the universe)? Is this what he calls a 'singularity'? Which I could think like this: when there is no time nothing can happen, except during this singularity.  Of course I don't know of a law that says 'when there is no time nothing can happen..', I just came up with it, as something intuitive.


find the equation of plane pass through three points: A(-5,0,4) B(0,-4,4) D(-5.0.0)  and  O (0,0,0) E (0,-4,0) G (0,0,4)


Can using an old flash damage a new DSLR?

I have been using my dad's old Metz mecablitz 18 B1 flash for a while with my Canon 7D and had no trouble with it, but just received some advice from a friend that using old flashes can fry the camera. Is this true? And if so, is there a safe way to use it (I'm trying to avoid having to buy a new flash – but also would like not to destroy my camera). The flash takes 3 x AA batteries and has a single hotshoe connection.


Vertical line only in one part of a table

I need some help on  putting a vertical line in the second part of the table, I don't know how to do it since the tabularx I declared does need to have that only in the second part. The code I used is:  \begin{tabularx}{\linewidth}{|XX|} \hline \multicolumn{2}{|c|}{\textbf{title name}}\\ \hline something: & else \\ something: & else \\ something: & else \\ \hline \multicolumn{2}{|c|}{bla bla blah}\\ \hline title text: & description 1 \\ title text: & description 1 \\ \hline \end{tabularx}   And the render of the table looks like this:    I just need a \vline between title text and description (it I use \vline it works only for the first line but the description text and sometimes the title, are few lines long).


Prove there is no bijective continuous function $f:[0,1] \to [0,1]^2$.  Here is my attempt so far: assume there a function $[0,1] \to [0,1]^2$ is continuous and surjective. We wish to show that it cannot be injective. Suppose in the contrary that it is injective. Then since the preimage of $f$ is compact and $f$ is bijective, its inverse $f^{-1}$ is a bijection from the unit square to $[0,1]$. Also, it is a uniform convergence.  I am also wondering if there is a not necessarily continuous bijection from the unit square to unit line.  I am not sure how to prove this problem. Any help would be great.


Is Alegaesia part of the same world as Lord of the Rings?

I started reading the Inheritance cycle by Christopher Paolini before I started reading J.R.R Tolkien's Lord of the Rings, and I have to say, they seem pretty similar in the books. Of how Eragon uses the Ancient language for magic, and in LOTR someone tells of mysterious people outside of the Spire, using the language of beasts and land, which describes the Ancient language. I don't know, please help.


Class of sets of a given infinite cardinality

This question was inspired by the question on .  From the discussion in the comments there, it seems there does not exist a set of all sets of a given cardinality.  To me, it seems easy to see that this is true for any nonzero finite cardinality $n$. Given any set $x$, you can always make a set of size $n$ by adding $n-1$ other sets to $x$ to make a set of size $n$, which exists by repeated use of the pairing axiom.   But how would you do this for infinite cardinalities? For suppose $\kappa$ is some given infinite cardinality. To show that the set of all sets of cardinality $\kappa$ does not exist, it seems you would have to show that for any set $x$, there exists a set of that size with $x$ as an element, and then you could take the union of that set to find the set of all sets, and thus a contradiction. But it doesn't seem reasonable to simply say, for a given set of size $\kappa$ if $x$ is in the set, we have no problem. If not, just take an element out of the set and put $x$ in. Something about that seems like it would not be allowed.  So how would you do this for infinite cardinalities?


I accidentally deleted a partition and my system won't boot

I deleted /dev/sda3, and now my system won't boot. I tried to use boot repair; but, it shows me an error message that says   GPT detected. Please create a BIOS-Boot partition   I created one but it doesn't work.    The image above shows the /dev/sda3 partition before it was deleted  This is what it shows now (@Pilot6)


How can I change the style of listing captions to "Listing. #"?

With the lstlistings package, is there a strait forward way of changing the label style from   Listing 1   to   Listing. 1   By the "label style" I mean the string used in the captions.  EG.   \begin{lstlisting}[caption=This is a caption, label=list]    here lieth some code \end{lstlisting}   would give me:  listing 1: This is a caption here lieth some code   However, What I need to get is (notice the punctuation after the listing):  listing. 1: This is a caption here lieth some code


Bounds for the Harmonic k-th partial sum.

I need to bound the k-th partial sum or the Harmonic series. i.e.   $$ln(k+1)<\sum_{m=1}^{k}\frac{1}{m}<1+ln(k)$$  I'm triying to integrate in $[m,m+1]$ in the relation $\frac{1}{m+1}<\frac{1}{x}<\frac{1}{m}$ for all $x\in[m,m+1]$ and I get: $$\int_{m}^{m+1}\frac{1}{m+1}dx<ln(m+1)-ln(m)<\int_{m}^{m+1}\frac{1}{m}dx$$ then $$\sum_{m=1}^{k}\frac{1}{m+1}<ln(k)<\sum_{m=1}^{k}\frac{1}{m}$$ but I don know how conclude or continue... please help.


I need that that application will start on my laptop screen when I launch, for example, "xterm". So if i start xterm in SSH my laptop must show me xterm on the screen, but it says, "DISPLAY is not set". What must i do with that?


How could I block DDOS attacks with fake Google bots?  I found 2 solutions on the net. But both seems to block also correct google bots.  # Block fake google when it's not coming from their IP range's (A fake googlebot) [F] => Failure RewriteCond %{HTTP:X-FORWARDED-FOR} !^66\.249\.(6[4-9]|[78][0-9]|9[0-5])\. RewriteCond %{HTTP_USER_AGENT} ^Mozilla/5\.0\ \(compatible;\Googlebot/2\.[01];\ \+http://www\.google\.com/bot\.html\)$ [NC] RewriteRule .* - [F,L] # End if match   And here is the second one:  # Validate Googlebots RewriteCond %{HTTP_USER_AGENT} ^Mozilla/5\.0\ \(compatible;\ Googlebot/2\.[01];\ \+http://www\.google\.com/bot\.html\)$ RewriteCond %{HTTP:Accept} ^\*/\*$ RewriteCond %{HTTP:Accept-Encoding} ="gzip,deflate" RewriteCond %{HTTP:Accept-Language} ="" RewriteCond %{HTTP:Accept-Charset} ="" RewriteCond %{HTTP:From} ="googlebot(at)googlebot.com" RewriteCond %{REMOTE_ADDR} ^66\.249\.(6[4-9]|7[0-9]|8[0-46-9]|9[0-5])\. [OR] RewriteCond %{REMOTE_ADDR} ^216\.239\.(3[2-9]|[45][0-9]|6[0-3])\.0 # Optional reverse-DNS-lookup replacement for IP-address check lines above # RewriteCond %{REMOTE_HOST} ^crawl(-([1-9][0-9]?|1[0-9]{2}|2[0-4][0-9]|25[0-5])){4}\.googlebot\.com$ RewriteRule ^ - [S=1] ## Block invalid Googlebots RewriteCond %{HTTP_USER_AGENT} Googlebot [NC] RewriteRule ^ - [F] # END sending now 403 to fake Googebots   Could anybody suggest a solution to block DDOS attacks with fake googlebots?


How to prevent the terminal from closing when the program it was started with ends?

If I start a terminal (any terminal, for example urxvt) like urxvt -e sleep 5, then a new terminal is launched but after 5 seconds the terminal closes, because the sleep program has ended. How can I start a terminal with a program on the command line, but have the terminal stay alive after that process has ended?  In practice, what I'd actually like to do is urxvt -e tmux new-session top, which opens urxvt with a tmux session that is running top. But when I press q, top ends which also causes tmux and urxvt to end as well. I'd like when I exit top for me to be taken to a shell within tmux.


Minecraft Vanilla crash IllegalStateException: Expected BEGIN_ARRAY but was STRING at line 1 column 1?

Whenever I click the icon on my desktop to get to Minecraft, the launcher loads as usual, like it should. But when I click the "Play" button, the launcher goes away, but then comes back saying this:  [17:15:14] [Client thread/INFO]: Setting user: kassidygallowway [17:15:14] [Client thread/INFO]: (Session ID is token:7b2075512917473abe32b04ffd11b2a4:ce288cc1399b4266a07c19cc48d47531) Exception in thread "Client thread" com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_ARRAY but was STRING at line 1 column 1     at com.google.gson.Gson.fromJson(Gson.java:815)     at com.google.gson.Gson.fromJson(Gson.java:768)     at lu.b(SourceFile:151)     at lu.<init>(SourceFile:43)     at net.minecraft.server.MinecraftServer.<init>(SourceFile:155)     at bpp.<init>(SourceFile:41)     at avf.<init>(SourceFile:293)     at net.minecraft.client.main.Main.main(SourceFile:124) Caused by: java.lang.IllegalStateException: Expected BEGIN_ARRAY but was STRING at line 1 column 1     at com.google.gson.stream.JsonReader.beginArray(JsonReader.java:338)     at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:79)     at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:60)     at com.google.gson.Gson.fromJson(Gson.java:803)     ... 7 more   I have no idea what this means (I dont know codes or anything like that). It does this over and over again, no matter how many times I press Play.


Why does USB only use 2 lines for RX, TX instead of multiple data lines?

Wouldn't it be faster if there were multiple data lines (say 8) to transmit/receive data (say sequential bytes) instead of using a single line to transmit sequential bits?


What sentence is correct and why:  In New York life is exciting. In New York the life is exciting.


Describe the elements of $\mathbb{Z}[i]/(3)$

I would like to describe the elements of $\mathbb{Z}[i]/(3)$. So I know that these elements look like $z+3\mathbb{Z}[i]$ and I tried to see when we have that $\hat{x}=\hat{y}$. I saw that this happens when we have that $x-y \in 3\mathbb{Z}[i]$ and if we consider $x=a+bi$ and $y=c+di$ then this means that $a\equiv c (\operatorname{mod} 3)$ and $b\equiv d (\operatorname{mod} 3)$, but afterwards I got stuck.


Run a command that is shadowed by an alias

Let's say I have the following alias in bash - alias ls='ls --color=auto' - and I want to call ordinary ls without options. Is the only way to do that is to unalias, do the command and then alias again? Or there is some nifty trick or workaround?


how do I make my nether portal work in minecraft pocket edition?

Where do I light my nether portal on Minecraft Pocket Edition 0.10.5?


How do I remove duplicate records in a join table in PostgreSQL?

I have a table that has a schema like this:  create_table "questions_tags", :id => false, :force => true do |t|         t.integer "question_id"         t.integer "tag_id"       end        add_index "questions_tags", ["question_id"], :name => "index_questions_tags_on_question_id"       add_index "questions_tags", ["tag_id"], :name => "index_questions_tags_on_tag_id"   I would like to remove records that are duplicates, i.e. they have both the same tag_id and question_id as another record.  What does the SQL look like for that?


Android - I modified vold.fstab and lost access to my SD card

I have samsung galaxy ace GT-S5830, it has very low internal memory (181 MB). I have an external micro SD card of 16 GB, but still couldn't install many apps due to insufficient internal memory. I read in internet that if i modify vold.fstab and replace the word sdcard with sdcard2 in it, then my external sd card  will act as internal memory.  So I rooted my phone and got superuser app (which can allow root access to various user apps) But I haven't installed clockworkmod recovery or any other custom ROM yet.  I installed ES File explorer on SD card and allowed root access to it via superuser app. I then went to /system/etc/ from ES file explorer , edited vold.fstab and replaced the word sdcard with sdcard2  Now i restarted my phone and the external SD is no more accessible. My "ES File Explorer" is also no more there for me to able  to undo the change that i did. I tried intalling ES file explorer again from my data connection, but the installation fails (and phone reboots immediately). I am not able to install any new apps.   I am unable to access my external SD card, so I can't put anything there via PC or via recovery.   I tried pressing the power button + home button to go into system recovery mode. I see only these options  Androd system recovery <3e>   reboot system now apply sdcard:update.zip wipe data/factory reset wipe cache partition   When i try to select the second option, it says installation aborted as the SD card is no more accessible   I tried to select 3rd and 4th options, but that didn't help either - I think factory reset will not reset vold.fstab :-(  I only have the default apps + superuser app now  I somehow need to find a way to get write permission to /system/etc or to /system/etc/vold.fstab  Luckily I found "Android Commander". Installing it on my windows PC and I am able to connect my android phone  and I am able to access root folder. But I am not able to push a modified vold.fstab to /system/etc because  Android Commander says "no Root Access" - It is seeing it as read only :-(  can someone let me know how i can edit this file again ? I have a original vold.fstab in my PC, but I am not able to push  it to my phone via Android Commander as Android Commander is seeing it as Read Only.  Is there a way to give root access (aka read-write access) to Android Commander via superuser app on my android ?  Is there any other way to get write permission to /system/etc/vold.fstab so that i can modify it or replace it ?


Interpretability of the dimensions in t-SNE

I'm relatively new to t-SNE and it seems that unlike in other dimensionality-reduction techniques, the dimensions in t-SNE are hard to interpret. The contribution of the variables can easily be accessed in PCA and MCA, and one can regress on the dimensions of MDS to know how each variable affects the position of the points in the n-dimensional space. Since there is no linear relationship between the dimensions and the points in t-SNE (at least that's what I've read somewhere), isn't there a way to get to know how the variables explain the dimensions?  I motivate my choice of t-SNE because it takes much less time to represent the distances than e.g. MDS. I'm using R version 3.4.4 (64-bit) and the Rtsne function from the package of the same name on a packard bell (Intel(R) Celeron(R) CPU B830 @ 1.80 GHz with 8,00 G RAM).  Thanking you in advance.


proper word or phrase for 'already eaten or drank by other person/animal'

Is there a single word or a short phrase to better describe a consumable item (e.g. drink or food) that has already been nibbled or sipped at? The relevance of this word or phrase would be in a situation where someone has eaten or drank some food such that it cannot be given to someone else, due to, for example, saliva.


Toward the end of "Diretide" games of Dota 2, both teams have to call a truce to battle Roshan, who is massively more powerful than in normal games, and is invincible-merely leveling up, on death.  What combination of heroes, items and abilities should me and my team use to kill Roshan as many times as possible before the timer expires?


What numbers can be written as a sum of two odd squares?

What numbers $n$ can be written as a sum of odd squares:  $$a^2 +b^2 = n$$ Where $a$ and $b$ are odd.  It is easy to see that all such numbers must be of form $2(4k+1)$ and if $4k+1$ is prime it can be written as a sum of $2$ squares. Beyond that, I am stumped.


Is there a good tutorial to understand how the different material windows work?

I'm getting mad at realizing how the material instances are assigned in Blender. Coming from Max, it's driving me crazy to not understand WHERE the material library for the scene is. I am branching here and there but without really a clue WHERE the material library is, and I can't have a concrete output with my materials, it doesn't work as I expect to. Is there any decent tutorial to understand how to manage the materials in the scene and assign them to objects like instances instead than like copies and copies and copies of the same material? Just to conclude: I am writing this question because I have an object that, no matter what, it doesn't want to show me one material. I tried to move up and down the materials in the material panel, change it, etc.: no way. And I don't know why. Here is a video:  What am I doing wrong?


how do i check if the session is going to expire in php

I have a usecase that i want to check if the session is going to expire in 30 sec or 60 sec. if so I should be able to extend the session. I am fine with any solutions with session or cookies. How do I acomplish that. Pls eloborate your solution. But I should know before the session expires.


Are there any English words that mean "an unlikely calamity" in that same way that "miracle" can mean "an unlikely beneficial event"?  My thesaurus only provides antonyms of "miracle" that mean "a mundane event" rather than "a horrible event".  I'm thinking specifically of multiple unlikely failures occurring simultaneously: I suffer an unlikely injury that leaves me unable to leave the house and my usually-reliable telephone service suddenly cuts out for the day, so I can't phone for help.  Words like "catastrophe" and "calamity" seem too general, since I'd like to express the exceptional unlikelihood of the event (or events). The best I have is a descriptive phrase like "disastrous coincidence," but I'd prefer a single word.  Overtones of the divine or demonic are not required, but preferred.


Good book on evaluating difficult definite integrals (without elementary antiderivatives)?

I am very interested in evaluating difficult definite integrals without elementary antiderivatives by manipulating the integral somehow (e.g. contour integration, interchanging order of integration/summation, differentiation under the integral sign, etc.), especially if they have elegant solutions.  However, I simply cannot seem to find a good book that covers many ways to evaluate these.  The single book that I know that covers some good techniques is the Schaum's Advanced Calculus. What is another good book that explains methods and techniques of integration of these fun integrals?


Why does this player not have a straight?

I'm relatively new to poker so bare with me.  Community cards: J, Q, K, 2, 4 P1: A,6 P2: Q,Q  A site determined that P2 won with three of the kind. Is this wrong? How does player P1 not win with a straight by playing only 1 hole card? The way this was graded confuses me!


tried to fix a bug in X11 and now black screen at boot

I had an issue with flickering on chrome and I saw what seemed to be a fix on the following thread:   so I did the following:  sudo nano /usr/share/X11/xorg.conf.d/20-intel.conf   Paste this:  Section "Device"    Identifier "Intel Graphics"    Driver "intel"    Option "AccelMethod" "sna"    Option "TearFree" "true"    Option "DRI" "3" EndSection Save (CTRL + O) and reboot."   Except than on reboot, after I enter my encryption password, I have a black screen. I'am on 16.04 and my computer is an Asus UX305F. I would be very grateful for any help. Thanks a lot.


Herstein Topics in Algebra, $\pi \mid a$ or $(\pi,a) = 1$

In Herstein’s Topics in Algebra, p.147, there is a sentence  If $\pi$ in $R$ is a prime element of $R$ and $a \in R$, then either $\pi \mid a$ or $(\pi,a) = 1$, for, in particular, $(\pi,a)$ is a divisor of $\pi$ so it must be $\pi$ or $1$ (or any unit).  I’m having a bit of difficulty seeing why the last part of this sentence is true (“for, in particular…”). Note:  Herstein’s definition of a prime element in a Euclidean ring $R$ is a nonunit $\pi$ such that whenever $\pi = ab$, where $a, b$ are in $R$, then one of $a$ or $b$ is a unit in $R$. This result comes before the Unique Factorization Theorem, so that can’t be used. However, we have proved that every element of a Euclidean ring $R$ is either a unit or can be written as a product of finitely many primes. (I don’t know if this is useful, but it’s what I tried to use, to no avail.)  My attempt: I tried supposing to the contrary, so that $(\pi,a)$ is neither $\pi$ nor $1$ nor a unit. Since $(\pi,a)$ divides $\pi$ we can write $\pi = (\pi,a)k$ for some $k \in R$. Then by definition of $\pi$ being prime, $k$ must be a unit, since $(\pi,a)$ isn’t. So $\pi$ and $(\pi,a)$ are associates. This is where I tried a few other things and got stuck each time.


How to show that $f$ is Riemann integrable?

Let $f$ be the function on $[0, 1]$ given by:  $$f(x) = \left\{\begin{array}{ll} 1 & : x \neq \frac{1}{2}\\\\ 2 & : x = \frac{1}{2}\end{array} \right.$$  Prove that $f$ is Riemann integrable and compute $\int_0^1 f(x)\,\mathrm dx$.  Hint: for each $\epsilon > 0$, find a partition $P$ so that $U_P (f) − L_P(f) \leq \epsilon$.  So I understand that I have to show that $U_P (f ) = L_P(f )$ to show that it is integrable, but I have no idea where to start. What partition do I pick and how do I even come about picking it?  Also as far as the integral, I figure that it is 1, although I'm not sure if I am right. Since it is a single point ($x = \frac{1}{2} $) where the function is not uniformly continuous, does it change the area as a whole?


Estimates of variance from an iid sample

There are two kinds of estimates of variance from an iid sample $X1, \dots, X_n$   $1/n * \sum_i (X_i - \bar{X})^2$, which is MLE $1/(n-1) * \sum_i (X_i - \bar{X})^2$, which is unbiased.   The unbiased estimate has a bigger variance than the MLE, for a given $n$.  So I wonder when to prefer which of the two? Thanks!


Finding the maximum likelihood estimators for this shifted exponential PDF?

Consider a random sample $X_1, X_2, \dots, X_n$ from the shifted exponential PDF $$f(x; \lambda, \theta) = \begin{cases}\lambda e^{-\lambda(x-\theta)} ;& x \geq \theta\\                     \theta ; &\text{Otherwise}\end{cases}$$ Taking $\theta = 0$ gives the pdf of the exponential distribution considered previously (with positive density to the right of zero). a. Obtain the maximum likelihood estimators of $\theta$ and $\lambda$. I followed the basic rules for the MLE and came up with: $$\lambda = \frac{n}{\sum_{i=1}^n(x_i - \theta)}$$ Should I take $\theta$ out and write it as $-n\theta$ and find $\theta$ in terms of $\lambda$?


Why handset manufacturers releases new versions of android several months after Google?

I have a nexus device. Whenever new version of android is released, the phone gets it almost instantly. I want to know why other manufacturers doesn't update their software in the same timespan. For some manufacturers, this process can take several months.  Is there a technical challenge that prevents them to do this? or is just matter of not allocating enough resources to do this?   I know about the differences between different ROMs and manufacturers, UI layers and so on... I'm asking is if so difficult (and why), or if manufacturers just don't want to do it, to release the new ROMs earlier.  To give an example about what I'm saying: when I updated from Windows 7/8 to Windows 10 in several computers (MSI, Acer, Lenovo, and custom build), I just clicked the "update" button and all the computers updated fine, without drivers problems... Why android is not the same case? Every major release introduces several breaking changes that makes it difficult for manufacturers?


I'm trying to understand a  of the following.  (a) Show that if $μ = (x_1, x_2, \dots, x_k) ∈ S_n$ is a $k$-cycle and $\sigma \in S_n$ is any permutation, then $\sigma μ \sigma^{−1}$ is the $k$-cycle $\sigma \mu \sigma^{−1} = (\sigma(x_1),\sigma(x_2), \dots ,\sigma(x_k))$. (b) Using the above, find a necessary and sufficient condition for two permutations in $S_n$ to be conjugate to each other.  It does not look like part (a) is done very clearly. Can someone explain it? Thanks


I've been trying to find a good solution to this problem for 2 hours, but I haven't found anything useful.   I have method that gets IssueData from mantisApi for use later in the code. It also catches any exceptions thrown:  try {      IssueData issue = mantisApi.getIssue(issueId, user);      task = prepareMantisTask(issue);     } catch (Exception e) {      System.out.println(e.getMessage());     }     return task;   The problem is when I get the IssueData I expect null because it might be an empty field. However when it returns, an exception is caught in this try/catch block. I tried to ignore using the following code:  public String getProjectNotNull(MantisTask mantisTask) {     if (mantisTask == null){         return null;     }     try{     String project = mantisApiCache.getProject(mantisTask.getProject()).getName();         return project;     }     catch(NullPointerException npe){     log.info("TaskService.getProjectNotNull() throws controled null");     return "-"; }   But it looks stupid when I have 20 or more records to check. Is there any other way to ignore nulls? Thank you for your time.  I'm sorry I'm at home now, and i cannot copy code.  prepareMantisTask looks like:  MantisTask mantisTask; mantistask.setId = issue.getId();   so example. if i do mantistask.setDueData = issue.getDueData(); it is null because not all issues have this parameter. So when the debugger get to this point, it returns to  } catch (Exception e) {          System.out.println(e.getMessage());  }    and left prepareMantisTask with task null.  This two pieces of code are from different parts of my program, I just wanted to show how it works.


Dynamic Allocation of Linked-List Array in C

I need to keep numbers of linked-lists in an array. I have followed similar questions but confused about implementation and cannot allocate the array correctly. I debugged, found, and simplified my problem: The array is always sized as 1 instead of N. As a result, I'm getting segmentation fault when try to use nodes. Simplified code:  typedef struct Node {     int data;     struct Node *next; } node;  int main(int argc, char** argv) {     node **array;     int N = 5;     array = (node **)calloc(N,sizeof(node*));     printf("Size of array = %d", sizeof(array)/sizeof(array[0]));     return 0; }   And the output is:  Size of array = 1   Here when I use static size for array as node *array[5] the output is:  Size of array = 5   Thanks for suggestions.


Find all positive integers $n$,$m$ with $n! = \frac{m(m-1)}{2}$

Let $n$ and $m$ be positive integers. Find all solutions of the equation $n! = \frac{m(m-1)}{2}$.  I found the following solutions: $(1,2)$, $(3,4)$, $(5,16)$,  and tried to find more solutions with a computer,  but there is no other solution with $n$ smaller than $1000$.


Stackexchange android app does not highlight questions with favourite tags unlike site

It would be nice if we get this feature on android app where questions with preferred tags are highlighted just like how it is on website.  Website view:    ===========================  Android app view:


MAAS Commissioned node does not boot - no bootable medium found

I just installed MAAS in a test environment, i.e., I set up two VMs in VirtualBox.  VM 1 runs the MAAS server and has two "virtual NICs". The first one is NATed to the outside network and the second one has a VBox host-only network without VBox's own DHCP server.  VM 2 only has one virtual NIC connected to the host-only network.  When I PXE-boot VM 2, it enlists correctly, and I can commission it. The commissioning completes and shows no error. When the node is ready as of the web interface, I start it from VBox, but then it says:  "FATAL: No bootable medium found! System halted."   What might I be missing?


If a field $F$ is an algebraic extension of a field $K$ then $(F:K)=(F(x):K(x))$

Suppose $K$ is a field and $F$ is an algebraic extension of some degree $n=(F:K)$. It is stated that the field of rational functions $F(x)$ is in fact an algebraic extension of the field $K(x)$ and moreover $(F(x):K(x))=n$.    How do I approach this exercise? I'm new in this area so any help would be greatly appreciated!


How to change caps lock key to backspace?

I use Windows 10. How can I change the caps lock key to do backspace?


rsync all files of remote machine over SSH without root user?

I have this command to backup a remote machine. The problem is that I need root rights to read and copy all files. I have no root user enabled for security reasons and use sudo the Ubuntu way. Would I need some cool piping or something to do this?  rsync -chavzP --stats user@192.168.1.2:/ /media/backupdisk/myserverbackup/