What are the rules on overfunding a 529 college savings account?

I read somewhere that overfunding a 529 account could be subject to taxes and a 10% penalty. Does anyone know how this works? Obviously, it is very difficult to predict the tuition costs 10 or 15 years ahead. I understand you can apply the overfunds to a another child or relative, but what if this is not these? Do you pay taxes + 10% penalty on all leftover funds?


Why cost of flights from canada to middle east equals to flight from canada to west europe?

So when I search for best flights from Vancouver to Tehran, I get prices around 1150 CAD for a round trip via Lufthansa which has a stop in either Frankfurt or Munich. Now if I search for the flights from Vancouver to Frankfurt or Munich, the prices don't really change.    That is also true about other Airliners like AirFrance. Surprisingly enough, the cost of a connected flight from Vancouver to Tehran via Air Canada plus Air France which stops in Calgary and then Paris is equal to a single flight from Calgary to Paris!    These are based on my searches on different times of the year, so they're not limited to a specific season.  Why does it happen? Am I missing something?


How do I cheaply carry a separate extra check-in bag in domestic flights in India?

I have booked a (return) ticket from Boston to New Delhi. In this flight, I'll be carrying two 23 kg bags. However, My destination is Kolkata. So, I'll be buying another (return) ticket from New Delhi to Kolkata, which is a domestic flight.  But most of the domestic flights in India does not allow two check-in bags. How do I manage to transfer the extra 23 kg bag?  I have checked with Jet Airways. They are saying that after the allowance of free check-in bag (23 kg with their US-payment site), I have to pay INR 300-500/kg. This will cost me huge for another 23 kg.  For Air India, they also do the same on the weight-basis, not on the piece-basis.  Any suggestions from the experienced people?


Static context error when using firebaseRecyclerAdapter

Non-static method cannot be referenced from a non-static context. The problem is coming from my PersonHolder.setPerson(person) with setPerson being underlined. Is this because the setPerson is inside of my onCreate?  I have 3 classes and 4 activity_layouts.    my activity_main class is just for the menu activity_main - just a menu Person class ReadFirebase class attached to my activity_read_firebase which is meant to pull the data from firebase and put it into my recycler. WriteToFirebase class used to send data to the firebase.   The last activity is my firebase_item_file that contains the items I require for my recycler in my activity_write_to_firebase.  public class ReadFirebase extends AppCompatActivity {      private FirebaseRecyclerAdapter<Player, PersonHolder> firebaseRecyclerAdapter;      @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_read_firebase);          RecyclerView recyclerView = findViewById(R.id.recyclerView);         recyclerView.setLayoutManager(new LinearLayoutManager(this));          DatabaseReference roofRef = FirebaseDatabase.getInstance().getReference();         Query query = roofRef.child("adult").child("male");          FirebaseRecyclerOptions<Person> firebaseRecyclerOptions = new FirebaseRecyclerOptions.Builder<Person>()                 .setQuery(query, Person.class)                 .build();          firebaseRecyclerAdapter = new FirebaseRecyclerAdapter<Person, PersonHolder>(firebaseRecyclerOptions) {             @Override             protected void onBindViewHolder(@NonNull PersonHolder personHolder, int i, @NonNull Person person) {                 PersonHolder.setPerson(person);             }              @NonNull             @Override             public PersonHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {                 View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.firebase_item_file, parent, false);                  return new PersonHolder(view);             }         };         recyclerView.setAdapter(firebaseRecyclerAdapter);      }     private class PersonHolder extends RecyclerView.ViewHolder {         private TextView name1;         private TextView name2;         private TextView name3;         private TextView age1;         private TextView age2;         private TextView age3;          PersonHolder(View itemView){             super(itemView);             pNameOne = itemView.findViewById(R.id.name1);             pNameTwo = itemView.findViewById(R.id.name2);             pNameThree = itemView.findViewById(R.id.name3);             pAgeOne = itemView.findViewById(R.id.age1);             pAgeTwo = itemView.findViewById(R.id.age2);             pAgeThree = itemView.findViewById(R.id.age3);         }          void setPerson(Person person){              String pName1 = person.getName();             pNameOne.setText(playerName1);             String pName2 = person.getName();             pNameTwo.setText(playerName2);             String pName3= person.getName();             pNameThree.setText(playerName3);             int pAge1= person.getAge();             pAgeOne.setText(Integer.toString(personAge1));             int pAge2 = person.getAge();             pAgeTwo.setText(Integer.toString(personAge2));             int pAge3 = person.getAge();             pAgeThree.setText(Integer.toString(personAge3));          } }


Vardi's Integral: $\int_{\pi/4}^{\pi/2} \ln (\ln(\tan x))dx $

Prove that:  $\displaystyle\int_{\pi/4}^{\pi/2} \ln (\ln(\tan x))dx =\frac{\pi}{2}\ln \left( \frac{\sqrt{2\pi} \Gamma \left(\dfrac{3}{4} \right)}{\Gamma \left(\dfrac{1}{4} \right)}\right)$  I know that the Vardi's Integral can be evaluated in terms of derivatives of Hurwitz Zeta Function. I would like to see a method which uses differentiation under the integral sign.


Join a wifi network only on macOS but not iOS

I have a WiFi network that I want to use from my macOS device (Sierra 10.12 / 2012 Macbook Pro), but not from my iOS device (iOS 10.2 / iPhone 7). The two devices use the same iCloud Keychain.  When I join from my macOS device, the iOS device joins the network as well. When I "forget this network" from the iOS device, the macOS device leaves as well.  Is there a way to decouple this? It's a corporate network, and I don't want to use it on my phone.


Why is my record update giving a null pointer exception?

I am creating notepad application and want to update my notes but I am unable to record in sqlite database. Please check my update query I am sharing error details.       public class MainUpdateActivity extends Activity  {   SQLiteDatabase mydb1; EditText titleedit,notetextedit; Button update;       @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_main2);          titleedit=(EditText)findViewById(R.id.title);         notetextedit=(EditText)findViewById(R.id.notetext);         update=(Button) findViewById(R.id.update);          Intent myintent = getIntent();          String product7 = myintent.getStringExtra("product1");         String product8 = myintent.getStringExtra("product");          titleedit.setText(product7);           notetextedit.setText(product8);  update.setOnClickListener(new View.OnClickListener()             {              public void onClick(View v)             { mydb1.execSQL("UPDATE notes SET (title,notetext) values(?,?);",new String[]{titleedit.getText().toString(),notetextedit.getText().toString()});  Toast.makeText(getApplicationContext(), "note Updated", 3000).show();                Intent myIntent1 = new Intent(MainUpdateActivity.this,menu.class);              startActivity(myIntent1);              finish();              }              });


Animated TV series with King Arthur / Sword in Stone theme; 'Excalibur' replaced by AI robot scepter

I am looking for an animated TV series which was probably made in the late 90s or early 2000s.  I seem to remember the setting is roughly medieval, except there are also elements of futuristic technology. The main theme of the story has a sort of King Arthur vibe in the sense that the hero is destined to save the kingdom.  The one distinctive thing that I remember for certain is that the central weapon/item of the main character is an artificially intelligent metal staff. Its head is an orb with a glowing yellow bulb or 'eye' on it (not unlike the appearance of the Starkiller Base from Star Wars: The Force Awakens). The shaft of the staff tapers down to a point, which can be plugged into sockets on various devices throughout the world to power or control them. Again with the King Arthur vibe I recall that this staff is his 'Excalibur' - it is implied that he is somehow destined to have it. Either its power or the knowledge contained within its AI is notably unique in-universe. When not doing anything exciting the main character often wore the staff slung over his back on a strap. It did have a voice and often spoke but I can't remember anything about its personality.  Sadly I can't remember any more details about the overarching plot or any of the other characters but I'm hoping this robotic mcguffin is unique enough that somebody recognises it.  Editing as requested: I watched the show in English (I am fairly confident it has a Western / non-Anime origin). I watched it broadcast free-to-air on NZ television probably in the early 2000s


I am stuck on the verify your account Google on a ZTE TracFone


Programmatically stop and start ArcGIS Server map services using Python in ArcGIS 10.5?

In his  to  @Jeff Berry posted how can we can programmatically stop and start ArcGIS Server 10.0 map services using Python.   How do I stop services in ArcGIS 10.5?   I couldn't find AGSSOM there.


Number of strings that start and end with the same letter or are palindromes or contain vowels only

In this question, we consider strings consisting of 26 characters, with each character being a uppercase letter. Determine the number of such strings that    (a) start and end with the same letter, or    (b) are palindromes, or    (c) contain vowels only   For this problem, I approached each scenario a, b, c separately. I then joined the 3 with an OR to satisfy the question in the final answer.  a. $26$ characters, if the last letter must be the same as the first, we really only have $25$ characters to choose from, so part a = $26^ {25}$  b. $26$ characters, but if it is a palindrome, the length is cut in half, giving us $26^{13}$.   c. If the characters are vowels only, there are only A E I O U, $5$ characters to choose from. And we have a full 26 characters to pick. $26^{5}$  The three value then gets OR'd together  $26^ {25}$ OR $26^{13}$ OR $26^{5}$    Is what I did correct? I'm working from practice problems and am not given an answer key so it's hard to really practice when I don't know if I'm doing it right or wrong. Thank you!


How to create a delay in Minecraft without repeaters?

I am trying to make a delay of 1 minute in a redstone circuit.  That would require 600 ticks. That s a lot of repeaters going to be used. Is there other ways of getting a 1 minute (or even longer) delays in a redstone circuit?


Show flag activity in profile even before flags processed

When a regular user flags something it disappears into the system until the flag is processed by someone.  This is OK for active sites, but for less active sites, or sites like Meta where only employees handle flags and so processing can be slow on weekends/holidays, one can lose track of one's flags, and can't be sure what flags have actually been raised and are pending.  (E.g., on  I'm pretty sure I raised a flag over a week ago, but nothing shows processed so how can I tell?)  Feature Request: Show all flags in  immediately, initially marked as "unprocessed".  Related:


how to install Ubuntu 14.04 on a Dynamic Disk?

Guy actually i am trying to install Ubuntu 14.04 using a USB but while installation the option along side Windows is missing. I heard that if we have a dynamic Disk, Ubuntu will not give the option along side windows.  So please help me out in installing Ubuntu 14.04 on my system.  My system configuration:  OS: Windows 7, Intel i3 processor, 4 GB RAM, 1TB Hard Disk.  Thanks in Advance :)


Complete list of App Store review rejection reasons

I am iOS Developer. I have seen and had very bad experiences with App Store approval process.  We have developed an app according to Apple standards which are defined on Apple's official site. Despite this, our app was rejected 2-3 times for different reasons.  Why does Apple not give all reasons for an app rejection? Where can I find more information about the app review process?


Prove that $n^4−1 $ is divisible by 5 when n is not divisible by 5.

Apparently the easiest method is to use proof by exhaustion, but I've no idea how. Any ideas/solutions? Prove that $n^4−1$ is divisible by 5 when n is not divisible by 5.


Do Sql Server backups contain transacitons during backup?

I have a database that automatically takes full backup weekly, differential backup daily, and transaction log backup every 5 minutes. The full backup takes about half an hour so its runtime often overlaps with the differential backup and any transaction log backups happens during. What happens to the data modified during each types of backup? Would they be included in the backup or the backup contains only data up to the point of BackupStartDate or other attributes in the backup? I want to be able to calculate when trying to restore to a point of time. If the Diff backup occurs after a full backup process has started and finishes after the full backup has finished, would it base on the last full backup or this one? I haven't found a authoratative explanation on the web. Appreciate if anyone can point me to the right direction.


What's different about photographing at sunrise vs. sunset?

I usually get better light at sunrise (compared to sunset). I do though hate to wake up early in the morning to use that light ;)  What are the biggest differences between sunrise and sunset?


Why do neutrinos propagate in a mass eigenstate?

I am aware that flavor $\neq$ mass eigenstate, which is how mixing happens, but whenever someone talks about neutrino oscillations they tend to state without motivation that when neutrinos are actually propagating, they are doing so in a mass eigenstate. Presumably this is glossed over because it is a deep and basic artifact of quantum mechanics that I'm missing, but I'm having trouble coming up with it.  I had some help  where they say      The mass eigenstates are the free-particle solution to the wave equation[...]   but I suppose "why is that" could be a more basic reformulation of my question! Why can't mass be time-dependent in the wave equation, yielding (I would think) eigenstates that don't have well-defined mass?


i have been using blender 2.8 for a couple of months but now i am stuck with a problem. I cant alter the properties of a new mesh in object mode. i need to reduce the vertices of a sphere but the properties are kind of frozen. please help!


How to automatically generate a stacktrace when my program crashes

I am working on Linux with the GCC compiler. When my C++ program crashes I would like it to automatically generate a stacktrace.  My program is being run by many different users and it also runs on Linux, Windows and Macintosh (all versions are compiled using gcc).  I would like my program to be able to generate a stack trace when it crashes and the next time the user runs it, it will ask them if it is ok to send the stack trace to me so I can track down the problem. I can handle the sending the info to me but I don't know how to generate the trace string. Any ideas?


How to make a flexible "garden" hose that can be controlled from both ends without losing shape?

I've been spinning my brain for the last few days trying to figure out how to do this. Basically, I need to make a hose (single tube shape, it doesn't have to be twisted like the image) that:  (1) Is naturally affected by gravity.   (2) Can be controlled from both ends of the hose, so both end points can be manipulated in keyframes.   (3) Won't deform or lose it's hose-like appearance when being moved around (like if someone was to literally move a garden house around in their front lawn).  Can anyone offer some insight into how I could accomplish this? Any advice would be greatly appreciated.  Thanks!


Is it possible to add badge won into "about me"?

I wanted to know if it is possible to add a badge earned in the presentation of his profile.  Like :


Using Fermat's little theorem I proved that     $$121^{199} = 121^{39} \mod 300$$   (as $\phi(300)$ is $80$) but I don't think I can leave it like this.  My question being how can I solve $121^{39}\hspace{-3mm}\mod 300$. Any ideas, suggestions?


Lightroom vs. Elements vs. Photoshop: Side-by-side comparison?

I'm a bit overwhelmed by the available options in regards to the three major photo editing apps from Adobe.  Does anyone know of an article or site that lists the features of Lightroom, PS Elements, and PS, side by side?  I know that Lightroom revolves around edits and workflow, and that PS is the big kahuna of image editing.  Where does Elements fit in to this understanding?


Select text in input box on user select or focus

I'm trying that when I change into drop-down, the input box should be focused and value of input box should be selected. I used   $("#text_qty").focus(function () {     this.select(); });   but it is not working .  This is my input box  <input type="number" name="text_qty" id="text_qty"  value="0" onKeyUp="cal_price()" onChange="cal_price()" min="0"/>


Creating Bootable USB with Rufus - Will Data be lost after every reboot?

In the answer of another question of mine, I was told that the official version for creating a bootable USB flash drive for Ubuntu is Rufus:    Now, I was just wondering, would the data be lost after every reboot?   Also, I read about the terms persistent and full install.  Would following the official version give me a persistent or full install?


Count total number of folders and files within a Folder

I have 1 directory. In this directory it contains 9folders(subdirectory). Each folder(subdirectory) contains a variable number of folders(subsubdirectory), and also in (subsubdirectory) it contains some folder....so on.... I tried this method but i dont know how to expand it because of variable number of subdirectory.          public static long GetDirectoryNumberOfFiles(string directory, bool includeSubDir)         {             long numberFiles = Directory.GetFiles(@directory).Length;              string[] subfolderEntries = Directory.GetDirectories(directory);//result 9              //i tried this, but without luck.             var dirInfo =new DirectoryInfo(directory);             int dirCount = dirInfo.GetDirectories().Length;//result 9               if (includeSubDir)             {               for (int i = 0; i < subfolderEntries.Count(); i++)               { numberFiles += Directory.GetFiles(subfolderEntries[i]).Length; }//result 38             }            return numberFiles;     }   When I right clicked the directory, it contains 23,026 files and 440folders. But with this method, i got 38files and 9folders. I know it just count the subdirectories but not all folders inside directory.


The difference between "as" "when" and "while"

What's the difference between "as", "when" and "while"?     The doorbell rang as/when/while Anna was asleep.   Which is right and why?


Update two table fields, each with the other value

Maybe someone can help me with this. I have a MYSQL table with first name and last name. Some rows were added with last name in the first name column and first name in the last name column. How can I flip these. I tried a simple update SET firstname = lastname, lastname = firstname but that doesn't work. Any help would be great.


I'm trying to send some data over WiFi using OkHttp3.   I created a client using,  import okhttp3.OkHttpClient; ..... public OkHttpClient client;   After the click of a button I set up the websocket,  private void start() {     Request request = new Request.Builder().url("ws://192.168.1.84:81/").build();     EchoWebSocketListener listener = new EchoWebSocketListener();     WebSocket ws = client.newWebSocket(request, listener);      client.dispatcher().executorService().shutdown(); }   Where EchoWebSocketListener is an extension of WebSocketListener, full listing below.  But I keep getting the following error at run time...  java.lang.NullPointerException: Attempt to invoke virtual method 'okhttp3.WebSocket okhttp3.OkHttpClient.newWebSocket(okhttp3.Request, okhttp3.WebSocketListener)' on a null object reference   When traced back its the line in the start() function,  WebSocket ws = client.newWebSocket(request, listener);   How come client is null?  Full code listing:  package qdivision.org.qrtracker;  import android.content.Intent; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.view.View; import android.widget.Button; import android.widget.EditText; import android.widget.ImageButton; import android.widget.TextView;  import okhttp3.OkHttpClient; import okhttp3.Request; import okhttp3.Response; import okhttp3.WebSocket; import okhttp3.WebSocketListener; import okio.ByteString;  public class Move extends AppCompatActivity {      public OkHttpClient client;     public TextView output;     private ImageButton forward;     public String dataFrame;       @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.activity_move);         Intent intent = getIntent();          forward  = (ImageButton) findViewById(R.id.forward_button);         forward.setOnClickListener(new View.OnClickListener() {             @Override             public void onClick(View view) {                 dataFrame = "<192.168.1.84,CMD,KEY,57,33>";                 start();             }         });     }      private final class EchoWebSocketListener extends WebSocketListener {         private static final int NORMAL_CLOSURE_STATUS = 1000;          @Override         public void onOpen(WebSocket webSocket, Response response) {             webSocket.send(dataFrame);             webSocket.close(NORMAL_CLOSURE_STATUS, "Goodbye !");         }          @Override         public void onMessage(WebSocket webSocket, String text) {             output("Receiving : " + text);         }          @Override         public void onMessage(WebSocket webSocket, ByteString bytes) {             output("Receiving bytes : " + bytes.hex());         }          @Override         public void onClosing(WebSocket webSocket, int code, String reason) {             webSocket.close(NORMAL_CLOSURE_STATUS, null);             //output("Closing : " + code + " / " + reason);         }          @Override         public void onFailure(WebSocket webSocket, Throwable t, Response response) {             output("Error : " + t.getMessage());         }     }      private void start() {         Request request = new Request.Builder().url("ws://192.168.1.84:81/").build();         EchoWebSocketListener listener = new EchoWebSocketListener();         WebSocket ws = client.newWebSocket(request, listener);          client.dispatcher().executorService().shutdown();     }      private void output(final String txt) {         runOnUiThread(new Runnable() {             @Override             public void run() {                 output.setText(output.getText().toString() + "\n\n" + txt);             }         });     }  }


How long does it take for a review to appear in the App Store?

On Friday, I went into the App Store on my iPhone and submitted a review for a game.  I just checked all the reviews for that game, and my review hasn't appeared yet.  About how long does it take for a review to appear in the App Store?


Is there a purpose to mowing grass in Roller Coaster Tycoon?

I've always wondered if having mowed lanws vs. weeds or plain grass has an effect on park guests or if it's merely cosmetic.


Why don't metals bond when touched together?

It is my understanding that metals are a crystal lattice of ions, held together by delocalized electrons, which move freely through the lattice (and conduct electricity, heat, etc.).   If two pieces of the same metal are touched together, why don't they bond?   It seems to me the delocalized electrons would move from one metal to the other, and extend the bond, holding the two pieces together. If the electrons don't move freely from one piece to the other, why would this not happen when a current is applied (through the two pieces)?


How to add a section* to the list of contents, but without giving it a number?

I have several section* 's in my LaTex text. But I only want the first one (abstract) to appear in the list of contents, although without a number. All the other section* 's are just a few subheadlines which should not appear anywhere and also don't have a number so far, which is good. Is there any exception regulation for this case only?


Proof that if $n^2/r^2 = p$, with $p$ prime, then $n$ is divisible by $p$

Given positive integers $n, r$, with $p$ a prime, and $n^2/r^2 = p$, prove that $n$ is divisible by $p$.  Use proof by contradiction (I am sure there are easier ways to prove this, but this is what the book requests, since the chapter is exercises on proof by contradiction). I started off by assuming that $n$ is not divisible by $p$, therefore: $n = ap + b$ for a non-negative integer $a$ and a positive integer $b$. $n^2 = pr^2$, so $(ap+b)^2 = pr^2$ I expanded this out to get a quadratic polynomial in $b$: $b^2 + 2apb + a^2p^2-r^2p = 0$ Using the quadratic formula, I found: $b = -ap \pm r\sqrt{p}$ Since $a$, $r$, and $p$ are integers, and $p$ is prime, then both of these values of $b$ would therefore be irrational, violating the condition that $b$ must be a positive integer. I'm not sure if this proof works or not.  It doesn't feel very elegant (compared to some of the examples in the book).  Could you please critique it?


I try to embed a view in a specific node. I found tutorials for doing this with Drupal 7 and PHP-Templates:  <?php print views_embed_view('view_name'); ?>   But I look for a way in Drupal 8 with twig-Templates. I tried to call the views_embed_view() function in the hook_node_view() and assign it to the node so that I can print it out in the twig-Template. But it seems that this hook never gets called.  Any hints/solutions how to do this in the Drupal 8 way?


Calculating the number of times a digit is written when given two numbers

My homework asks me the following:     If a student writes the integers from 5 to 305 inclusive by hand, how many times will she write the digit 5?   I started out by writing every number that contains 5 and I got 31, but 31 is not among the answers possible:     5, 15, 25, 35, 45, 55, 65, 75, 85, 95, 105, 115, 125, 135, 145, 155, 165, 175, 185, 195, 205, 215, 225, 235, 245, 255, 265, 275, 285, 295, 305   I counted 55, 155, and 255 as two each since there are two occurrences of the digit 5 in each.  I can't figure out what I'm doing wrong.  In addition, suppose I were given the numbers 1 and 100,000 - writing them out isn't efficient, and I would assume there's a formula for this but I can't figure that out either.


QGIS 2 runtime error message on Windows 8:new install

I am getting the following error message:       Run Time Error   Program:C:\PROGRA~1\bin\qgis-bin.exe   R6034   An application made an attempt to load C runtime library incorrectly   Contact application suppliers"   My operating system is Windows 8 2012. I have a 64 bit operating system QGIS version Desktop 2.0.1, Browser 2.0.1. This is following download when I try to open the Desktop   I am not hugely computer operating system literate so please can the answers avoid too much jargon!!


How can I use \linebreak inside a node, in tikz?

This is my code, which doesn't work:  \documentclass{article} \usepackage{tikz} \begin{document} \tikz \node {start\linebreak{}stop}; \end{document}   The \linebreak command doesn't work. In order to make it working I have to say \node[text width=5em]... Is there any other method to make it working, without explicit specification of the node text width?


C# - How to implement begin trans, commit trans, and rollback in SQL Server

I would like to insert a function in my code which is begin,commit, and rollback trans because the data is prone to errors. my code is this:  clsDBConnect dbConn = new clsDBConnect(); SqlCommand CMD; SqlDataReader Reader;  private void Save() {      CMD = new SqlCommand("SELECT * FROM tblEmployees", dbConn.connection);       Reader = CMD.ExecuteReader();       while (Reader.Reader())      {           while(variable1 != variable2)           {                //Lots of CMD.ExecuteNonQuery();                //Lots of Reader                //Lots of computation                variable1 += 1;           }      } }   How can I rollback inserts and updates when error occurs during the loop?  Thanks!


No indentation for non-item within itemize

When using itemize list, I would like to include text which is not part of the bullet points. Is it possible not to indent it the way items are indented?  \begin{itemize} \item One Subsequently, we only want to count the cases... \item Two The subsequent order of the other neighbors... \item Three \end{itemize}


Can a negative ever mean the opposite outside of double negatives? "ex: I was not a little disturbed by the news"

I saw this sentence while reading:"The mansion was lovely-she particularly liked the topiary-but not a little intimidating." I don't understand the function of the not? from context she is intimidated, why is she saying she's not? Is little considered a negative and this is one of those stylistic double negatives?  Is the sentence just wrong? I remember seeing/hearing similar sentences in other older books and poetry but can't remember exact sources... thanks!


Duplicate meta descriptions & title tags

I have website and have some issue with duplicate description and title. Can any body help me to solve this error in easy and simple words?


Build and strengthen the Stack Exchange community with "crossover questions" between sites

I've been a Stack Exchange contributor for a couple of years now, currently most active on . One thing that keeps coming up is questions that would appeal to audiences on two different Stack Exchange sites but there are almost no features taking advantage of these questions. On travel.SE we have crossover questions most often with  and possibly next most often with  - but it can happen with almost any SE site. Today alone we had  with  and  had . I am absolutely sure that this must happen all the time between arbitrary pairs of Stack Exchange sites but the only feature that takes advantage of it is the possibility of migrating off-topic questions which leaves the original question acting as a redirect across the two sites. I think there is a missed opportunity to build the network between sites where users of one site don't realize they could make valuable contributions to a sister site they have had so far little to do with. At the very least there could be a way to "advertise" a question on a second site that could be interested in it. Probably by listing it in the sidebar where there are also links to meta questions, linked questions, related questions, new blog posts, and But there could also be some kind of features that make some sort of acceptable crossposting. There could be gamification/badges added around building cross-site questions or whatever else you can think up. I think this is a great way for people to spread their expertise from their main site onto other sites, to make the network stronger and more cohesive, to bring more attention to questions that would have a divided audience between two sites. I can think only of positives and no negatives. Does anyone else have some ideas to add or think this is a bad idea for any reason?  Example crossover questions: Here are some links to some crossover questions I've been finding in the Stack Exchange network here. (This was previously posted as an answer, but more people wanted it to be part of the question.)   ▶  :   ▶  :   ▶  :   ▶  :   ▶  :   ▶  :   ▶  :   ▶  :   ▶  :   ▶  :   ▶  :   ▶  :   ▶  :


MAPE yielding value of 1000+ for timeseries forecasting

I am comparing a model's outcome with the actual values for a span of 9 months. I am expecting a very large error, however my MAPE implementation yields 1404512.56 using python, pandas.  Here is my implementation:  def mean_absolute_percentage_error(y_true, y_pred):     y_true, y_pred = np.array(y_true), np.array(y_pred)     return np.mean(np.abs((y_true - y_pred) / y_true)) * 100   There were instances in y_true (the actual values) where they were 0, but I have replaced them with 0.001 to avoid division by 0.   If anyone could provide a hint as to what MAPE means when it's that high, I'd appreciate it.


16.04 Update not offered via update manager

Good morning,   my update manager is not showing the update to 16.04, but if I use the terminal sudo do-release-upgrade -d I'm asked to upgrade. I'm using 14.04. Is it just a matter of time or do we have to update manually?  Thanks


I have a US Business/Tourist Visa on my Indian Passport and want to travel to Mexico City for business. Can I travel via Amsterdam? I want to avoid transiting US as it is increasing my travel cost.


What is the reason for some very popular sites like Reddit use ugly User Interface?

I got a project to build a website like Reddit. My client need a very attractive modern look interface.  But he asked that why Reddit website look so ugly? IS there any UI /UX reason for it?  I did not have a answer when he asking. I said I will do a research and let you know. But still I could not find the reson for it...


KKT versus unconstrained formulation of lasso regression

L1 penalized regression (aka lasso) is presented in two formulations.  Let the two objective functions be $$ Q_1 = \frac{1}{2}||Y - X\beta||_2^2 \\ Q_2 =\frac{1}{2}||Y - X\beta||_2^2 + \lambda ||\beta||_1. $$ Then the two different formulations are  $$ \text{argmin}_\beta \; Q_1 $$ subject to $$ ||\beta||_1 \leq t, $$ and, equivalently $$ \text{argmin}_\beta \; Q_2. $$ Using the Karush-Kuhn-Tucker (KKT) conditions, it's easy to see how the stationarity condition for the first formulation is equivalent to taking the gradient of the second formulation and setting it equal to 0.  What I can not find, nor figure out, is how the complementary slackness condition for the first formulation, $\lambda\left(||\beta||_1 - t\right) = 0$, is guaranteed to be fulfilled by the solution to the second formulation.


For $A,B \in \mathscr{M}_{2\times2}(\mathbb{Q}) $ of finite order, show that $AB$ has infinite order

Let $G$ be the group $ ( \mathscr{M}_{2\times2}(\mathbb{Q}) , \times ) $ of nonsingular matrices.  Let $ A = \left ( \begin{matrix}  0 & -1 \\   1 & 0  \end{matrix} \right ) $, the order of $A$ is $4$;  Let $ B = \left ( \begin{matrix}  0 & 1 \\   -1 & -1  \end{matrix} \right ) $, the order of $B$ is $3$.  Show that $AB$ has infinite order.    The only reasoning possible here is by contradiction as $G$ is not abelian. And so I tried, but I got stuck before any concrete development.  Any hints are welcome, Thanks.


How to prove that the remainder of $15^{2098}$ divided by $14$ is $1$?

I have to compute the remainder of $15^{2098}$ divided by $14$, I know that the answer will be $1$ because $15$ is $14+1$ and the remainder of every $15$'s power will be $1$ when divided by $14$, the problem is that I can't write that as answer because it is not too mathematical, so I want know how can I prove this without having to do all the long computation.


Dense subset has at most one point on each horizontal/vertical line

Show that there is a dense subset $S$ of $A=[0,1]\times [0,1]$ such that $S$ contains at most one point on each vertical line and at most one point on each horizontal line.   When I think about dense subsets and which contain "not so many" points, the rational numbers come to mind. So if we take $P=\mathbb{Q}\cap[0,1]$, and $S=P\times P$, then we do have the closure of $S$ equal $A$. However, $S$ contains more than one point on each vertical/horizontal line (in fact, infinitely many). How might we adjust so that each horizontal/vertical line contains at most one point in $S$?


I have an  tag coming back from a php file in a json format, it is as follows:  $subarray[] = '...';   This one works fine. However, reading some material on unobtrusive JavaScript, I'd like to remove that onclick="profile(\'' . $row['id'] . '\')" and instead add an id to the tag, and then listen for the time the id is clicked. Hence, the code will be something like the following:  $subarray[] = '...';   However, when I try to listen for the event to happen, in a code like the following:  $("#some").click(function() {         alert('hi');     });   nothing happens. I would much appreciate it if you could tell me how to solve the problem, and let me know what is the best practice here.


Movie with laser shooting into space and two white guys at a bar

While flying to a wedding last weekend I caught a few glimpses of a movie that a fellow passenger was watching that looked interesting. I could not hear any audio and I only caught a couple minutes of what I presume was the beginning of the movie. The first scene had a group of scientists discussing aspects of 3 planets, which I believe were Venus, Earth, and Mars. A screen shows that Venus's temperature was +250 degrees (I didn't see what scale). Later, the shot zooms above what kind of looks like a solar collection tower in a mountainous area. Energy gathers together at the center, sort of Death Star style, and then shoots a yellowish beam into space. The next scene shows two white guys at a dimly lit bar with some neon lights. I did not recognize any of the actors in any of these scenes, but it seems like a fairly recent movie, probably no more than 10 years old.


Can we please stop adding notifications you have to dismiss on every single site separately?

There's a new notification about review queues that was added a few days ago. I think it is a good idea in general to remind users that the review queues exist. Every notification is a slight annoyance, but I think this one is a reasonable one on paper. But the actual implementation isn't reasonable, it's simply annoying for anyone using more than one SE site. The notification can be dismissed, but that dismissal isn't remembered network-wide, you have to dismiss it on every single site separately. I use several SE sites actively, and I also tend to occasionally browse the hot network questions for interesting or diverting content. Having to dismiss the same notification that often is just tedious. This isn't the first time a global notification that has to be dismissed per site was added. It also isn't the second or third time, this happens every single time SE adds something like this. Sometimes when we complain enough a network-wide option is added later, but never from the start. I know this isn't as simple technically as might appear, but it is possible. I don't think it is an unreasonable burden to include the work necessary for a proper network-wide dismissal for every kind of global notification SE adds. And if it appears too much effort to do that, is that notification really that important that you need to show it to everyone? Please just make dismissing notifications, popups and anything else like this always network-wide, and not just add this option after we complain on meta again. I'm just tired of complaining about this issue again and again.


simple java error i don't know how to fix

I am new to Java. I wrote this program and when I run it, it always gives me that the answer is 0.0   Can you tell me what I did wrong?  import java.util.Scanner; public class Learnclass {     public static void main(String[] args) {         Double fnum, snum;         Double ans = 0.0;         String opr;         Scanner getIn = new Scanner(System.in);           System.out.print("Enter your first number: ");         fnum = getIn.nextDouble();         System.out.print("Enter your second number: ");         snum = getIn.nextDouble();         System.out.print("Enter the operation: ");         opr = getIn.next();       if(opr == "add") {         ans = fnum + snum;    }       System.out.print("Answer is " + ans); }  }


How do I navigate between directories in terminal?

I am new to Linux and Ubuntu and have tried changing to folders/directories with some difficulty.  Could someone explain why the following commands failed to change to the desired target folder/directory?  sharon@sharon:~$ cd Home  bash: cd: Home: No such file or directory  sharon@sharon:~$ cd /Home  bash: cd: /Home: No such file or directory  sharon@sharon:~$ cd Documents  sharon@sharon:~/Documents$ cd Downloads  bash: cd: Downloads: No such file or directory  sharon@sharon:~/Documents$ cd /Downloads  bash: cd: /Downloads: No such file or directory  sharon@sharon:~/Documents$


How can i transform my Boolean list of lists to 1s and 0s?

[[ True False False  True  True  True  True  True  True False False  True    True  True  True  True  True  True  True  True  True  True  True  True   False False  True  True  True  True False False False  True  True  True   False False False  True  True  True  True  True  True  True False False    True  True  True False False  True]  [ True False False  True  True  True  True  True  True  True  True  True    True False False  True  True  True False False  True  True False False   False False False False  True  True False False False  True  True False   False False False False  True  True  True False False False False False   False False False False False False]]   assuming the outcome of bw_np = numpy.asarray(bw) is a list of lists althought i don't see commas, no commas between elements within sublists either?  What i tried:  for element in bw_np:     for sub in element:         sub = sub*1         print(sub) print(bw_np)


Does kinetic energy affect temperature of an object?

Imagine a fundamental particle at rest with respect to ground frame and has temperature $x$ degrees celsius and imagine a 'similar' particle moving at a very high speed (take any value which would affect temperature significantly). So the particle moving has temperature greater than $x$ degrees celsius or exactly equal to $x$ degrees celsius?


How to sync gnome-calendar with an online calendar?

I thought it was awesome that Ubuntu 16.04 shipped with gnome-calendar, but I noticed that holidays were not included.  I also noticed that there is an option to sync the calendar with an online one, how do I do this?  I don't know of any online calendars I could use.


How close is the Geneva Airport train station to the airport?

My plane departs from Geneva Airport (Geneva International terminal M) at 19:55. I'll be in Zürich and a bit short on time. If I take the train that arrives at "Genève-Aéroport" at 18:51, will I have enough time to find the terminal and check in? I've never been to this airport before.


What do I do if I suspect someone has downvoted a lot of my posts?

Someone has downvoted a lot of my questions or answers.   What should I do?  How does the system prevent this? How often does the system look for suspicious behavior?


Windows Key seems to be stuck (not physically)

Good morning everybody! I've seen similar threads but none solved my issue.   My Asus EEEPC 1015PE has Windows 8.1 installed and it's going on and off on an issue that the Windows Key will be stuck. It's not stuck physically, as I try pressing it and it won't go to Metro. I removed the key and sprayed a contact cleaner, it still wouldn't unstick.   I looked into the post  and tried uninstalling the keyboard driver as it was suggested, uninstalling Windows 8 Start Menu (Classic Shell, Start Menu 8, WinAeroCharmsBarKiller and whatnot) programs and even tried as a last resort to remove the Windows Hotkeys via Regedit with the following methods:   [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer] "NoWinKeys"=dword:00000001    [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Keyboard Layout] "Scancode Map"=hex:00,00,00,00,00,00,00,00,02,00,00,00,00,00,5B,E0,00,00,00,00  Tried Microsoft's KB216893, but this one wouldn't do the trick as it's not for Windows 8/8.1  I have also tried disabling some functions from Ease of Access to no success.  Not even the last method worked fully, as even though it stopped going to Search when I pressed "S" and stopped going to Run when I pressed "R", it will still Logout when I press "L" and malfunction with other keys. Even with the On-Screen Keyboard if I press "L" it will logout.  I remember having flashed a portable OS to rule any Windows 8.1 software issue out, and it seemed the key was still stuck, although I didn't test it this time I believe if I try it it will still be an issue.  So, what should I do? Is changing the keyboard my only option? Thanks!


How did planets have an elliptical orbit in the first place?

I know that planets speed up when getting closer to the sun, but they speed up because they have an elliptical orbit, and they have an elliptical orbit because they speed up. Why did they have an elliptical orbit in the first place?


$\mathbb{Q}(\sqrt{p},\sqrt[3]{q})= \mathbb{Q}(\sqrt{p}\cdot \sqrt[3]{q})$ ??

Let $p,q$ be primes, $p≠q$, then I have to show that $\mathbb{Q}(\sqrt{p},\sqrt[3]{q})= \mathbb{Q}(\sqrt{p}\cdot \sqrt[3]{q})$  So far I've tried a lot of things with minimal polynomials and bases, but I'm far from any argument that I find sufficient.  This is an example from my algebra course, first chapter about field extension. So far we know about basic definitions, minimal polynomials and their properties, algebraic elements and algebraic fields.  Could someone maybe give me a hint about how to proceed? Thanks a lot!!!


String.Join vs. StringBuilder: which is faster?

In a  about formatting a double[][] to CSV format,  that using StringBuilder would be faster than String.Join. Is this true?


Can't login because password contains characters not in keyboard

Recently I set a password containing small c cedilla (ç) and now I can't type it on login menu because it doesn't use the Spanish but English keyboard and types a slash, resulting in wrong password. How could I login?


I find ore but as I destroy it, it doesn't drop. Why?

I built my own mine and found gold and diamonds, but no matter what I used to destroy them, they just disappeared. I didn't get anything at all.  Why is this?


Whenever I move an object the entire scene is re-rendered

Whenever I move one of the objects in my scene, blender automatically re-renders the entire scene as if I had pressed the render button. How can I turn this off?


Is there a word that means deliberately ignorant, choosing to ignore?

I know what this word really means but I cannot help to think that ignorant also means he ignores his surrounding or the consequences of his actions. "He was ignorant, unwilling to warn the police about what has been happening next door for years” for example. Can anyone tell me the word I am looking for? Or is it too broad to find a suitable adjective?


Import a local bash file into another bash file

I have var.sh  name="John" age="29"   I also have main.sh  eval "var.sh" echo "My name is $name"   When I run, I kept getting   ⚡  Desktop  bash main.sh  main.sh: line 1: var.sh: command not found My name is    What is the best practice to import a local bash file into another bash file ?  Is there way that will work on Mac OS X, Linux and Windows ?


Why are there only four fundamental interactions of nature?

Is there an answer to the question why there are only four ?


I created a simple script on Ubuntu Server 18.04:  #!/bin/bash apt update apt upgrade   then I changed the owner to root  # chown root update.sh   then I added SUID bit and execution bits for user and group  # chmod u+xs,g+x update.sh   and this is what I have:  -rwsrwxr-- 1 root  me  35 Mar 21 09:48 update.sh*   So I was expecting that by running this script which I have permission to run (it belongs to my group), it gets the root UID and it will execute as root, but I get permission denied.


How do I simplify $\sum_{k=1}^n \gcd(k,n)$?

For a given positive integer $n$, how do I simplify $$\sum_{k=1}^n \gcd(k,n)?$$  By simplification I mean is there any formula which makes it easier to compute it (rather than just compute each term and sum up)?


null pointer exception on linked list java when adding a node before the last

I'm trying to add a node before the last node in a linked list but I'm having a null pointer expecption on one on of my tests. my code:     IntegerNode current = head; IntegerNode newNode = new IntegerNode( value ); IntegerNode prev = head;   }


JQuery with dynamically-created content?

the issue I'm having is that the .on(click()) event works with the paragraphs generated through the dialog box, but not when they are created through the textbox entry() method. When I inspect them the IDs are correct and in the same format as the dialog-created paragraphs, but they don't work with the click event. Clicking on the dynamically created paragraphs doesn't even fire the click event at all. What do I need to do to solve this? thanks.  HTML:              <link rel="stylesheet" type="text/css" href="stylesheet.css">          <link rel="stylesheet" href="http://maxcdn.bootstrapcdn.com/bootstrap/3.2.0/css/bootstrap.min.css">                          <input type="text" id="txtTask" onkeydown="entry();"/>

       JS:  var tasks = []; var content = "";  $(document).ready(function (){  for(var i = 0; i < 5; i++) {      content = prompt("Enter a task", i);      if(content != "") {          addTask(content, "yellow");      }; };  for(var i = 0; i < 5; i++) {      console.log(tasks[i].Content); };      $( 'p' ).on( "click", function() {      console.log("clicked");     removeTask(this.id);  });    });    function entry()  { if (event.keyCode == 13) {      var ent = txtTask.value.toString();      if(ent != "") {          addTask(ent, "yellow");      };      console.log("input = " + txtTask.value);     txtTask.value='';  };  };  function addTask(content, color) { tasks[tasks.length] = {     Content: content,     Color: color,     isActive: true };  $('#taskBox').append('
' + tasks[tasks.length - 1].Content + '
'); };  function removeTask(content) { for(var i = 0; i < tasks.length; i++){      if(tasks[i].Content === content && tasks[i].isActive === true) {          tasks[i].isActive === false;          $('#' + tasks[i].Content).remove();     }  }; };


There seems to be in increasing discussion about pie charts.   The main arguments against it seem to be:   Area is perceived with less power than length. Pie charts have very low data-point-to-pixel ratio   However, I think they can be somehow useful when portraying proportions. I agree to use a table in most cases but when you are writing a business report and you've just included hundreds of tables why not having a pie chart?  I'm curious about what the community thinks about this topic. Further references are welcome.  I include a couple of links:         In order to conclude this question I decided to build an example of pie-chart vs waffle-chart.


Redirect to detail page after saving record using force:navigateToSobject

I am getting error as      "This page has an error. You might just need to refresh it. Error in   $A.getCallback() [Cannot read property 'setParams' of undefined]   Callback failed:   apex://QuickCreateOppCtr/ACTION$creatOpportunityRecord Failing   descriptor: {c:QuickCreateOpp}" after saving record.   Record is created but not redirecting opportunity detail page from Account list view but it is redirecting from account detail page  Below is the lightning component controller.  action.setCallback(this,function(result){             component.set("v.isShow",false);             //component.set("v.objDetail.AccountId", component.get("v.recordId"));             //alert('component.get("v.recordId") ---->' +component.get("v.recordId"));             var oppId = result.getReturnValue();             alert('Opportunity is created. oppId -->'+oppId);               var navEvent = $A.get("e.force:navigateToSObject");          navEvent.setParams({               recordId: result.getReturnValue(),               slideDevName: "detail"          });          navEvent.fire();          });         $A.enqueueAction(action);


Does every infinite-dimensional inner product space have an orthonormal basis?

For a finite-dimensional inner product space $V$, since it has a finite basis, then we can do the Gram-Schimidt process to produce an orthonormal basis. However, the Gram-Schmidt process does not work with infinitely many vectors. So it is natural to ask, does every infinite-dimensional inner product space have an orthonormal basis? If the answer is yes, how to prove it?  PS: For "basis", I mean the Hamel basis.


error: no such device grub rescue Windows 7

I have a hard drive with Windows 7 installed on and I wanted to install Ubuntu 12.04 onto an external hard drive. So I made a LiveUSB with Ubuntu 12.04 on and installed it to the external hard drive. I then deleted the partition and re-formatted the external hard drive that had Ubuntu on.  When I go to turn on my laptop now (with the Windows 7 hard drive) I get this.  error: no such device: c74908d5-9525-4fdc-a89a-cfa380052200. Entering rescue mode... grub rescue> ls (hd0) (hd0,msdos3) (hd0,msdos2) (hd0,msdos1) grub rescue>   I do not have the original disk that contained the Windows 7 OS on, I have seen from other forums that this can be used to repair the boot loader for windows. So obviously I am in a sticky situation.  I have another external hard drive with Ubuntu 14.04 on and when I connect an external hard drive case with the Windows 7 hard drive on. I can access these folders from Ubuntu 14.04.  :   :   If anyone has any help as to how I can fix this problem, I would greatly appreciate it.


A story about Earth in far future with a civilization centered around a huge tree

I'd like to ask you to help me identify a sci-fi/fantasy book that I read probably sometime in the 90s though I don't know when it was written. Here are the plot points that I remember:   the story starts with a human on contemporary Earth being turned to stone (or probably something much more exotic) by some sort of experiment gone wrong, he is turned back to his original form millions of years later by a lightning or some similar phenomenon, the local population considers him a god or a prophet since his "stone form" was a center of a cult before he was awaken, the population is not human but consists of creatures evolved from various contemporary animals, one of the most important locations is a huge tree which is so ridiculously big that it contains multiple settlements.


How can I center all the contents in the page, and make the order be right-to-left, because the alignment is to the left and the order is left to right.  here is the code:  Edit Center parent div       .grid-item {   float: left;   width: 270px;   min-height: 260px;   max-height: 260px;   background-color: whitesmoke;   margin-bottom: 10px;   border: solid 5px #bfbbd9;   padding: 7px; }

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SQL Server compatibility with New TLS Standards

The major browsers are moving beyond SSL3.0 and TLS1.0 . The PCI Security Council has declared an end-of-life date for these protocols to be considered sufficiently strong encryption.   We need to move away from these protocols, to use newer and stronger ones. On Windows servers, you can very easily disable these old protocols, and instead offer only TLS1.1 or greater.  However, as noted , Microsoft SQL Server 2008 R2 and SQL Server 2012 (Standard, at least) both will not start if those lower protocols are disabled.  However, there are a growing number of versions of MS SQL Server.  There are SQL Server Standard, Business Intelligence, Enterprise, Express, Web, and Compact editions.  And of course there is SQL Server 2008, 2012, 2014, and (in pre-release) 2016.  Which of these editions support or will support the use of only TLS1.1 or greater protocols?


What's the difference between "double* grade", "double *grade", and "double* fn()"?

Pointer variables are confusing to me. Consider the code below:  int main() {double* grade; double *grade;}  double* fn() {}   What is the difference between double* grade and double *grade? What is the difference between double, double* in int main(), and double* of fn()?


I am getting the following error trying to read from a socket. I'm doing a readInt() on that InputStream, and I am getting this error. Perusing the documentation this suggests that the client part of the connection closed the connection. In this scenario, I am the server.  I have access to the client log files and it is not closing the connection, and in fact its log files suggest I am closing the connection. So does anybody have an idea why this is happening? What else to check for? Does this arise when there are local resources that are perhaps reaching thresholds?    I do note that I have the following line:  socket.setSoTimeout(10000);   just prior to the readInt(). There is a reason for this (long story), but just curious, are there circumstances under which this might lead to the indicated error? I have the server running in my IDE, and I happened to leave my IDE stuck on a breakpoint, and I then noticed the exact same errors begin appearing in my own logs in my IDE.  Anyway, just mentioning it, hopefully not a red herring. :-(


When are the product of cyclic groups also cyclic?

In general, products of cyclic groups are not cyclic. If $C_n$ is the cyclic group of order $n$, $C_{22} \times C_{33}$ is not cyclic. But is there an easy way to tell when such a product will be cyclic?


Slow internet on desktop, but not on laptop? Where do i look to resolve this?

I've been dealing with internet issues since i moved into my new appartment. So originally i'm obligated to 100/100, which is what i am also receiving - I am reaching those speeds on WiFi with my laptop and on ethernet connection on laptop. When i connect to my desktop with ethernet i am only getting about 10/10? What could be the reason for this? Edit: Fixed by following this thread:


Angular momentum of a rolling sphere in relation to axis

This might be an old question but I can't seem to find a satisfactory answer.   Suppose I pushed a sphere with for a certain amount of time and let it roll across a rough surface. Disregarding deformations and air resistance etc., it will **roll without slipping ** with a constant angular velocity( or will it?). And I will include only the sphere in my system of interest.   If I choose the contact point as the axis, everything is fine : there's no net external torque because position vector is zero, and angular momentum is conserved. However, if I chose the center of mass of the sphere as the axis, the friction force ( seems to ) exert a net torque on the system and the sphere should change angular velocity.   Where did it went wrong? That is my question. Is there some fictitious(or real) forces that I'm missing?    I am completely new here so if there is some mistakes I made, I sincerely apologise. And thanks in advance!


Suffixing by "-rama", "-orama" or "-arama" — how did this begin?

Suffixing by -rama, -orama or -arama — how did this begin? I mean words like futurama, foodarama, etc.


Computing the Galois group of $x^4+ax^2+b \in \mathbb{Q}[x] $

I want to compute the Galois group of some polynomials, but I want to see some examples first. For example this proposition could be helpful. I don't know how to prove it <.<  Let's consider a polynomial $f(x)= x^4+ax^2+b \in \mathbb{Z} $. Let $ \pm\alpha , \pm\beta$ denote the roots of $f(x)$. Note that $f$ is irreducible iff $\alpha^2, \alpha\pm\beta \notin \mathbb{Q}$. So let's suppose that $f(x)$ is irreducible. Let's denote $G$ the galois group of $f$ (the Galois group of the splitting field $\mathbb{Q}(\alpha,\beta)/\mathbb{Q}$)  $i)$ $G\cong V$ the Klein 4-group iff $\alpha\beta \in \mathbb{Q}$  $ii)$ $G\cong \mathbb{Z}_4$ iff $\mathbb{Q}(\alpha\beta)=\mathbb{Q}(\alpha^2)$  $iii)$ $G\cong D_8$ the dihedral group of order 8, iff $\alpha\beta \notin \mathbb{Q}(\alpha^2)$  I need help with the proofs of this propositions... Well I'm very lost with the computation of Galois group, some care must be exercised, I don't have it. For example I know that Galois group acts transitively, in the sense that $u\in K/F$ a galois extension, the other roots of the minimal polynomial of $m_u(x)\in F[x]$ are precisely the elements $ \sigma(u)$ , where $\sigma \in Gal(K/F)$. And clearly any automorphism, is determined by only the value of a basis. In this case we are working on $\mathbb{Q}(\alpha,\beta)$, so I have to know the values of both. But I have to respect the algebraic relations involving $\alpha , \beta$ I proved that in $i),ii)$ $\mathbb{Q}(\alpha,\beta) = \mathbb{Q}(\alpha) $ So I have to know the values on $\alpha$.   My first question is: If in both cases $i),ii)$, I have an extension of degree 4 (so $|G|=4$) I have to map $\alpha$ to determine the automorphism, but I have also to map $\alpha$ to all of it's four roots. Why the galois group in this case are different?  My second question is about $iii)$ I have no idea How to attack it.


Ubuntu 18.04 LTS - I can't seem to install wine staging or uninstall wine itself

Everytime I type..  sudo apt-add-repository 'deb https://dl.winehq.org/wine-builds/ubuntu/ bionic main'    I get...  E: Malformed entry 53 in list file /etc/apt/sources.list (Component) E: The list of sources could not be read.   Same thing if I try to purge wine.


Parametric vs non-parametric machine learning methods

I looked-up many references and websites and researched on how to determine if a method is between parametric or non-parametric. I came up with below definitions,     A parametric algorithm has a fixed number of parameters. In contrast, a non-parametric algorithm uses a flexible number of parameters, and the number of parameters often grows as it learns from more data.   From .  Moreover, I found,     A parametric model, we have a finite number of parameters, and in nonparametric models, the number of parameters is (potentially) infinite.    From .  And many other methods of determination, though the problem is none of them can helo ones to determine if a certain hypothetical method is parametric or not. (For instance, why k-means' number of parameters are constant but KNN is variable or basically what do we call a parameter and what we do not?)


Remove-spdeletedsite will raise the following error "unable to find the specified path"

I run the following command:-  get-spdeletedsite   which showed me a list of deleted site collections, now i run the following to remove the deleted sites as follow:-  remove-spdeletedsite 032**********   but i got the following error :-     unable to find the specified path     now i try  to run the following script :-  Add-PSSnapin Microsoft.SharePoint.PowerShell $CorruptSites = "http://***/sites/***"  Function DeleteCorruptSite { param($CorruptSite) Write-Host $CorruptSite : -foreground red $site = Get-SPSite $CorruptSite $siteId = $site.Id $siteDatabase = $site.ContentDatabase  $siteDatabase.ForceDeleteSite($siteId, $false, $false) Write-Host --Deleted from Content DB -foreground green } foreach ($CorruptSite in $CorruptSites) {  DeleteCorruptSite $CorruptSite }   but i got the following exception also:-  http://***/sites/*** : Get-SPSite : Cannot find an SPSite object with Id or Url: http://***/sites/***. At C:\Users\***\Desktop\1.ps1:10 char:9 + $site = Get-SPSite $CorruptSite +         ~~~~~~~~~~~~~~~~~~~~~~~     + CategoryInfo          : InvalidData: (Microsoft.Share...SPCmdletGetSite:SPCmdletGetSite) [Get-SPSite], SPCmdletPipeBindException     + FullyQualifiedErrorId : Microsoft.SharePoint.PowerShell.SPCmdletGetSite   so can anyone adivce on this please ?i remember that i tried to remove this site collection using the central administration UI. but it raised an exception and the site content database and site collection administrator became empty,, so is there a way to remove corrupted deleted site collection ?


$\lim_{n \rightarrow \infty}\left(1+\dfrac{2}{n}\right)^{n^2}e^{-2n}$ $\lim_{n \rightarrow \infty}\left(e^{-2}\left(1+\dfrac{2}{n}\right)^n\right)^{n}$ It is indeterminate form $1^{\infty}$ I solve this like this $e^{\lim_{n \rightarrow \infty}}\frac{\ln(e^{-2}(1+\frac{2}{n})^n)}{\frac{1}{n}}$ I can't apply L'Hôpital's rule now how can I solve this problem quickly?


How do i find the position of a specific item in a list using while/for loops using python?

Say I have a list=['apple','orange','durian','blackberry']  How do I find the position of 'durian' using while or for loops I know there's a code called list.index('durian') but I want to know the position of the specific item using for/while loops


I have this electronics that uses 3V rechargeable coin cell battery (ML2032) to power the RTC when the system is off. When the system is powered on it'll trickle charge the battery instead.  I'm looking for ways to allow the usage of regular non-rechargeable CR2032 battery instead. One way I see people doing on Amiga, which also uses 3V rechargeable battery, is to simply add a Schottky diode in series. However, I wonder if there is something even better. To me a voltage drop of at least 0.15V is a lot for a 3V battery.


How do I remove the BOM character from my xml file

I am using xsl to control the output of my xml file, but the BOM character is being added.


Running apt-get upgrade or apt-get dist-upgrade fails due to Java7 installer 404

I'm currently trying to run a upgrade or dist upgrade on my ubuntu 14.04.  The problem is it keeps trying to install the Java7 installer and     Here is the error output  $ sudo apt-get upgrade Reading package lists... Done Building dependency tree        Reading state information... Done Calculating upgrade... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. 1 not fully installed or removed. After this operation, 0 B of additional disk space will be used. Do you want to continue? [Y/n] y Setting up oracle-java7-installer (7u80+7u60arm-0~webupd8~1) ... Downloading Oracle Java 7... --2017-06-13 13:10:12--  http://download.oracle.com/otn-pub/java/jdk/7u80-b15/jdk-7u80-linux-x64.tar.gz Resolving download.oracle.com (download.oracle.com)... 184.51.112.98, 184.51.112.96 Connecting to download.oracle.com (download.oracle.com)|184.51.112.98|:80... connected. HTTP request sent, awaiting response... 302 Moved Temporarily Location: https://edelivery.oracle.com/otn-pub/java/jdk/7u80-b15/jdk-7u80-linux-x64.tar.gz [following] --2017-06-13 13:10:12--  https://edelivery.oracle.com/otn-pub/java/jdk/7u80-b15/jdk-7u80-linux-x64.tar.gz Resolving edelivery.oracle.com (edelivery.oracle.com)... 104.84.148.179, 2600:1400:4:18f::2d3e, 2600:1400:4:19c::2d3e Connecting to edelivery.oracle.com (edelivery.oracle.com)|104.84.148.179|:443... connected. HTTP request sent, awaiting response... 302 Moved Temporarily Location: http://download.oracle.com/otn-pub/java/jdk/7u80-b15/jdk-7u80-linux-x64.tar.gz?AuthParam=1497373933_4797392087922e2a3b76cad4594d357c [following] --2017-06-13 13:10:13--  http://download.oracle.com/otn-pub/java/jdk/7u80-b15/jdk-7u80-linux-x64.tar.gz?AuthParam=1497373933_4797392087922e2a3b76cad4594d357c Connecting to download.oracle.com (download.oracle.com)|184.51.112.98|:80... connected. HTTP request sent, awaiting response... 404 Not Found 2017-06-13 13:10:15 ERROR 404: Not Found.  download failed Oracle JDK 7 is NOT installed. dpkg: error processing package oracle-java7-installer (--configure):  subprocess installed post-installation script returned error exit status 1 Errors were encountered while processing:  oracle-java7-installer E: Sub-process /usr/bin/dpkg returned an error code (1)


What is the longest passenger flight (with a flight number) in the world?

For example, JQ151 from Sydney to Christchurch is around 3 hours.  NZ1 however, is about another 7 to Hong Kong.  Will need a regular flight number to verify.  Definition is longest in terms of flight time / distance (they should be linked, logically?).


$a,b,c \geq 0$ and $a^2+b^2+c^2+abc=4$ prove that $ab+bc+ac-abc \leq 2$ can any one help me with this problem,I believe Dirichlet's theorem is the key for this sorry for making mistake over and over again,but i'm certain that the inequality is true now.


{5,15,25,35} is a group under multiplication mod 40

Show that the set $\{5,15,25,35\}$ is a group under multiplication modulo $40$. What is the identity element of this group. Can you see any relationship between this group and $\mathbb U(8)$?   I am very stuck on this question and I think my knowledge of abstract algebra is my liability at the moment. Right now I'm most confused by the fact that I learned: An element of a group of this nature must be relatively prime with the working mod.  Obviously here this is not the case, so I don't really know where to begin.  Do I need a Cayley Table?  Thanks.


I get this error when I try to run my file. I try to put in a reference, but I only got [?]. This is the main document:  \documentclass[10pt,a4paper]{article} \usepackage{standalone} \usepackage[english]{babel} \begin{document} \tableofcontents \newpage % Hieronder voeg je de hoofdstukken in \input{../tex/hoofdstuk1} \input{../tex/hoofdstuk2} \newpage \section*{References} \bibliography{bibliography.bib} \end{document}    And this is the .bib file.   In the file hoofdstuk2 I refer to a source like this: \cite{Tsao2013558} I don't understand why my reference is displayed as [?]. Can someone help me?


Are there any ways to evade a zone of truth, outside of clever wording? how would modify memory impact this? could you modify memory yourself to make what you believe what you are saying the truth?


whenever I run, sudo apt-get update, I find one is  :    Err http://ppa.launchpad.net saucy/main i386 Packages   404  Not Found in i386 packages of ppa                                 and 2nd : W: Failed to fetch http://ppa.launchpad.net/upubuntu-com/flareget-i386/ubuntu/dists/saucy/main/binary-i386/Packages  404  Not Found   I think there is problem in installation of flareget software is there any command to fix this


No regularisation term for bias unit in neural network

According to , weight decay (regularization) is not usually applied to the bias terms b why?  What is significance (intuition) behind it?


What caused NullPointerException: null? I have no idea about it, my laptop just installed android studio, after I import my project, it can't run because of this. Not problems of the project I think because it runs normally in my PC.  null java.lang.NullPointerException    java.lang.IllegalArgumentException: Argument 0 for @NotNull parameter of com/intellij/util/ui/UIUtil.isFocusAncestor must not be null     at com.intellij.util.ui.UIUtil.isFocusAncestor(UIUtil.java)     at com.intellij.ui.content.impl.ContentManagerImpl.isSelectionHoldsFocus(ContentManagerImpl.java:558)     at com.intellij.ui.content.impl.ContentManagerImpl.setSelectedContent(ContentManagerImpl.java:513)     at com.intellij.ui.content.impl.ContentManagerImpl.setSelectedContentCB(ContentManagerImpl.java:496)     at com.intellij.ui.content.impl.ContentManagerImpl.setSelectedContentCB(ContentManagerImpl.java:485)     at com.intellij.ui.content.impl.ContentManagerImpl.setSelectedContentCB(ContentManagerImpl.java:569)     at com.intellij.ui.content.impl.ContentManagerImpl.setSelectedContent(ContentManagerImpl.java:574)     at com.android.tools.idea.gradle.invoker.GradleTasksExecutor.showMessages(GradleTasksExecutor.java:651)     at com.android.tools.idea.gradle.invoker.GradleTasksExecutor.access$1600(GradleTasksExecutor.java:106)     at com.android.tools.idea.gradle.invoker.GradleTasksExecutor$3$2.run(GradleTasksExecutor.java:326)     at com.intellij.openapi.application.impl.LaterInvocator$FlushQueue.run(LaterInvocator.java:319)     at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311)     at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:744)     at java.awt.EventQueue.access$400(EventQueue.java:97)     at java.awt.EventQueue$3.run(EventQueue.java:697)     at java.awt.EventQueue$3.run(EventQueue.java:691)     at java.security.AccessController.doPrivileged(Native Method)     at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:75)     at java.awt.EventQueue.dispatchEvent(EventQueue.java:714)     at com.intellij.ide.IdeEventQueue.defaultDispatchEvent(IdeEventQueue.java:697)     at com.intellij.ide.IdeEventQueue._dispatchEvent(IdeEventQueue.java:524)     at com.intellij.ide.IdeEventQueue.dispatchEvent(IdeEventQueue.java:335)     at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)     at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)     at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)     at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)     at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)     at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)


Can I practically demonstrate Gravitational Time Dilation by spinning a wheel very fast?

In an attempt to demonstrate gravitational time dilation, I was curious if it were practical to mount a clock to a fast spinning wheel, with the centripetal acceleration of the wheel being equivalent to a gravitational field.  I wanted to calculate the velocity the wheel would need to rotate at in order to measure a time dilation of 1μs, when the clock is placed 1m from the center of the wheel.  Since this isn't a common lab or high-school experiment, I didn't expect the velocity to be very practical.  Is it correct to use the following approximation to compute the required velocity within the same order of magnitude as the "correct" answer (from: )?  I substituted $v^2/r$ and $r$ for $g$ and $h$ respectively.  $$T = 1 + \frac{gh}{c^2}$$ $$T = 1 + \frac{gr}{c^2}$$ $$T = 1 + \frac{rv^2}{rc^2}$$ $$T = 1 + \frac{v^2}{c^2}$$  For $T = 1 + 10^-6$s, $v = 3x10^5 m/s$, which is clearly far too fast.  Are my calculations correct, given my assumptions and requirements?


Can you end Heat Metal's disadvantage by dropping an affected weapon on your turn?

Heavily related to   (possibly a duplicate in a way)  states:     If a creature is holding or wearing the object and takes the damage from it, the creature must succeed on a Constitution saving throw or drop the object if it can. If it doesn't drop the object, it has disadvantage on attack rolls and ability checks until the start of your next turn...   If you are suffering disadvantage from holding a weapon affected by heat metal, does dropping the weapon remove the disadvantage or does the phrase "If it doesn't drop the object" only refer to the possibility of dropping it at the time of the casting?


Induction involving series with exponents $(1+2+3+\cdots+n)^2=1^3+2^3+3^3+\cdots+n^3$

Does anyone have any hints for proving the following via mathematical induction?   Obviously the base case is easy enough... I'm getting stuck on how these exponents may be manipulated to show $S_k\Rightarrow S_{k+1}$.  Here is the proposition:   Prove that $(1+2+3+\cdots+n)^2=1^3+2^3+3^3+\cdots+n^3$ for every $n\in\mathbb{N}$.


Chromium 34 and later cannot detect flash plugin

I've deleted ~/.macromedia and ~/.adobe contents and after a restart chromium can't detect flash plugin. It works just fine in Firefox  I have only "Chromoting Viewer" on chrome://plugins/  chromium-browser 34.0.1847.116-0ubuntu2 adobe-flashplugin 11.2.202.350-0trusty1   I have profile-sync-daemon active (tried stopping it, of course) and broken PolicyKit as in   Does the detection depend on PolicyKit? What else can I do?


The terminology of orthogonal matrix vs. orthonormal matrix

I know the definition of an orthogonal matrix. Also there are orthonormal basis. And if two vectors are orthogonal, their scalar product is zero etc. It seems the name "orthonormal matrix" more relevant to other definitions. My question is why it is called orthogonal matrix instead of orthonormal matrix or by another name? Is there any deep reason behind that? Thanks


For a continuous positive funciton $f(x)$ on $[0,1]$, with maximum value $M$, show that $$\lim_{n\rightarrow \infty}\left(\int_0^1f^n(x)dx\right)^{\frac{1}{n}}=M$$


How to remove comma and "and" before institutional last author after compiling BibTeX

I have the following BibTeX entry:  @article{pubmed18800157,     author = {Heng, T.S. and Painter, M.W. and Immunological Genome Project Consortium},     title = {The {I}mmunological {G}enome {P}roject: networks of gene expression in immune cells.},     journal = {Nat. Immunol.},     pages = {1091-1094},     volume = {9},     number ={10},     year = {2008}, }, %\bibliographystyle{unsrt}   When the bibliography is generated, it puts comma a the end of the author:   Notice the comma after M.W. Painter. Is there a way to remove it?


After upgrading from Ubuntu 16.04 to 18.04, I get the following dependency problem:  Preparing to unpack .../linux-tools-4.15.0-34_4.15.0-34.37_amd64.deb ... Unpacking linux-tools-4.15.0-34 (4.15.0-34.37) ... dpkg: error processing archive /var/cache/apt/archives/linux-tools-4.15.0-34_4.15.0-34.37_amd64.deb (--unpack):  trying to overwrite '/usr/lib/libcpupower.so.4.15.0-34', which is also in package linux-hwe-tools-4.15.0-34 4.15.0-34.37~16.04.1 dpkg-deb: error: paste subprocess was killed by signal (Broken pipe) Errors were encountered while processing:  /var/cache/apt/archives/linux-tools-4.15.0-34_4.15.0-34.37_amd64.deb E: Sub-process /usr/bin/dpkg returned an error code (1)   Any ideas how to fix this?


When commenting before deleting a post, is the comment lost?

Sometimes it is appropriate to delete your own answer or question. That is often because someone explained a problem, and one accepts that the question or answer is not valuable. That is not directly related to down voting - an answer may be well liked, but not actually applicable.  When I agree to delete it based on the comment, I would typically like to reply to the comment - just before deleting the post. This comment I write is associated with that deleted post, and becomes unavailable with it. But that does not mean it is immediately completely lost.   I write that comment not to have it permanently associated with the question or answer, but to reply to the comment that convinced me to delete the post. It is typically to roughly explain my reasoning - or just thanking for the hint by explaining that I learned something from it.  All that is relevant to me is that the recipient (indicated by @) can somehow read the comment - even if it does not become permanent. It could appear in the inbox - and would be visible in part there - truncated to fit the space. Does the notification stay in the inbox even if the associated post is deleted? Can it still be read in full?


Using player selectors in titles in minecraft 1.13

I'm playing Minecraft 1.13.2 and I am trying to code a command block that outputs a Title when a player dies. The Title needs to include the dead players name. This is the code I have but it just lists all players on line, not the one that died.  /execute if entity @a[scores={Deaths=1}] run title @a title [{"selector":"@a Deaths=1]"},{"text":" has died! "}]


Stack Exchange OpenID credentials not removed on logout, allowing insecure re-login

The cookies for subdomain, 'openid.stackexchange.com' are not, as claimed, actually removed from the browser upon logging out of stackexchange.com, but they should be.  Applies to: * stackexchange.com, date: January 8, 2012  Desired result:   Upon logging out of Stack Exchange, Stack Exchange OpenID local credentials stored 'in your browser' (or stored anywhere on the user's computer) should actually be deleted, as promised. For example, Stack Exchange OpenID browser cookies actually should be deleted. Logging in again should require explicitly entering one's credentials again. This might be email address and password. It is misleading to claim that (all relevant) 'local credentials in your browser' are deleted, since anyone else sitting down at the same computer can merely click the login links and immediately be accepted as the same, previous user! (See procedure to duplicate, below.)   Procedure to duplicate the problem in FireFox:  Versions (Menu-Help-Troubleshooting Information-Application Basics-User Agent): * Mozilla/5.0 (Windows NT 5.1; rv:9.0.1) Gecko/20100101 Firefox/9.0.1   Start FireFox. In Firefox's cookies manager (Menu-Tools-Options-Privacy), click the button, 'Exceptions', enter stackexchange.com and stackoverflow.com, and each time, click the button, 'Allow for Session'. Click the button, 'Close'. Click the button, 'Show Cookies'. Type, 'Stack', select stackexchange.com and stackoverflow.com if they are there, and each time, click the button, 'Remove Cookies'. Close Firefox. Start Firefox. Close webmail notifier windows. Log out of Gmail. Wait ten seconds. Click the back button on the browser to make sure one is not still logged in to Gmail. Open a tab for,  . In , if you have it, allow the domains, 'stackexchange.com' and, 'sstatic.net' and refresh. Click the link at the top, 'login'. On the resulting page, click the box, 'Log in with Stack Exchange.' Enter one's Gmail email address and Stack Exchange password, which results in a successful Stack Exchange login. Click the link at the top, 'logout'. The resulting web page has an orange button labeled, 'logout', above which is presented the text, 'Clicking Log Out will clear all local credentials in your browser.' Click the orange button labeled, 'logout'.   One might think that one has completely logged out safely from Stack Exchange, with no possibility of simply clicking back in. But, not true!   Now the page has the link at the top, 'login'. However, the Firefox Cookie Manager still shows cookies under domains, 'stackexchange.com' and 'openid.stackexchange.com'. Click the link at the top, 'login'. On the resulting page, again click the box, 'Log in with Stack Exchange.' See the login unexpectedly succeed, without entering any email address or Stack Exchange password!


Do new QGIS installation packages uninstall or override any previously installed versions of QGIS?

My organisation has restricted installing software on all workstations to I.T. administrators only, so I am not able to check this myself.  All applications, including QGIS, are pushed through Software Center.  Recently, they pushed QGIS 2.18.8 and it removed the last LTR version of QGIS and latest 2.18.6 version, from everyone's workstation.  I wanted to confirm, would the new QGIS 2.18.8 installer have uninstalled both the previously installed QGIS versions, or could it be something set in the Software Center distribution/installation process?  We would like to be able to always have a LTR version of QGIS to fall back on, if the test version has issues, so I am trying to narrow down the problem.  This is different to the suggested duplicate topic in that there is a software deployment application being used and not manual installations of QGIS to individual users. I want to determine if the uninstalls are done by Software Center or by the QGIS installation package by default. We also don't want standalone versions, preferring to run multiple QGIS versions. One LTR and one Latest for testing new features.


I've just learned about the Heartbleed Bug (OpenSSL leaking private keys), and based on the website, heartbleed.com, it says that OpenSSL 1.0.1 through version f is affected. However it leaves off Ubuntu 13.04 off the affected list AND the repositories do not have an update to it.  Let me paste some information here:  demortes@vps:/$ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description:    Ubuntu 13.04 Release:        13.04 Codename:       raring   AND  demortes@vps:/$ openssl OpenSSL> version OpenSSL 1.0.1c 10 May 2012 OpenSSL>   I'm seeing that we're not affected even though I have 1.0.1c installed... is this accurate. If not, how can I install OpenSSL 1.0.1g with package management now? If it is accurate... why?


How do I work out if a USB-C cable is safe to use?

There's a lot of press about how  - as I understand it, they have the wrong resistor, and that causes the device to draw too much power.  On the other hand, I'd like to get a cheap USB A to C cables for stashing around the house. I also currently have a probably nonstandard cable that came with the phone - designed to handle up to 5v 4A - I have a one plus three and its part of the dash charge quick charge system. I'm assuming that's safe for use with a PC though.  While "get cables that have been tested by " is a good idea, having a standard way to test my cables that do not involve having a nexus 5x or 6p would be nice.  From what I understand, the issue is with excessive current draw - would monitoring the current draw phone side, with an app like ampere be sufficient, and what current is 'safe' for a phone connected to a PC?   If I were to wish to check the resistance, where would it be?   In short, how, short of picking up another phone (a nexus- and using check), can I test to see if its safe for my current phone and pc(s)?  I'll be using a variety of possible charging sources - but more importantly, I want a cable spare I can use to connect my phone for data transfer. For my purposes, let's assume a windows 10 PC with a powered USB hub as a baseline for testing. I'd likely use legacy USB A -> USB C cables for the most part.   I'd also add, it's plausible that the problem might be specific to certain phone/pc combinations. The OP2 apparently would use any USB cable, in spec or not. The nexuses might not have. Hence testing for my hardware


Determine convergence of $\sum_{n=1}^{\infty}a_n$

Let $a_n=1-2^{\frac{-1}{n}}$, $b_n=\frac{1}{n^p}$. Does $\sum_{n=1}^{\infty}a_n$ converge or diverge when compared to $\sum_{n=1}^{\infty}b_n$ if $p < 1$? My answer to this is that it diverges, since $b_n$ diverges if $p<1$, and by a comparison test $a_n$ does as well. Is this correct? Thank you.


Proving that the map from a topological space to a fiber bundle is open.

There are two pieces to a question, the first:  Let G be a group acting on a space $E$. Show that the quotient map $E \rightarrow E/G$ is open.  The second:  Let p : E → X be a fiber bundle. Show that p is an open map.    My thoughts are the following.  First we see what a "fiber" is: If for E and X as topological spaces we let $p:E \rightarrow X$ be a mapping, $U \subseteq X$ and $U$ is a neighborhood of $x$, then $p^{-1}(x) \in E$ where $p$ is called the fiber over $x$.    The fiber bundle is one such that:  $\forall y \in E \space\space \exists U \subset X \text{ where }\phi_{U}:p^{-1}(U) \text{ is homeomorphic to the product space } F \times U \text{ where } F \text{ is the fiber bundle }$  Now I address the second piece first as I have a better idea of why this would be true, however could use some clarification.  On this page:    It says: "Every fiber bundle is an open map, since projections of products are open maps."  While I don't see why the projections of products are open maps (unless they are just referring to topological spaces as top. spaces are both open and closed), I am wondering if p is an open map as by the definition of a fiber bundle we have that since the product space $F \times U$ is open as $U$ is an open neighborhood of $x$ then since the pre-image $p^{-1}(x) \in E$ is homeomorphic to $F \times U$ then $p$ has to be an open map.  As for the first part, since $E$ is a Topological space and hence it is open, then if I mod out some closed set it would still be open.  Is there more to it than this?  Thanks,  Brian


Using bitwise logic to test Control.MouseButtons

Can someone kindly explain how this works?  if ((Control.MouseButtons & MouseButtons.Left) != 0)   MSDN only says that Control.MouseButtons Property gets a value indicating which of the mouse buttons is in a pressed state but I can't understand how that '&' works and why should it be different than 0.


Is it possible to declare a template class as a friend class without specifying the template parameters

Here is a small code example :  template <typename T> class A {      // }  class B {     friend class A<..> }   In this case, I want A to be declared as a friend class but without specifying the template parameters...


Spatial Join Points and Polygons in ArcGIS Desktop?

I am trying to create a grid road map with an index table for street look up.  I am using this tutorial by ESRI:   I am at the step whereby I am supposed to spatially join a point file (centroid point for each label) to a grid (which has the grid ID):      The next step is to use the Spatial Join tool (one to many is the join   option) and join the annotation to each grid cell they fall within.    However, you will likely not want to work directly with the annotation   because the spatial join options for “contains” or “within” will not   include any annotation that overlaps more than one grid cell. Further,   the “intersects” option will create duplicate entries in the same   circumstances. To get around that convert the annotation to point   features using the Feature to Point tool (Important note: I had to   delete the Element field; the type is blob, the field isn’t needed,   but if it’s there, the tool won’t run).   It seems to be telling me to spatially join the points to the grid in order to match up each label point with its grid ID value. However, whenever I spatially join, the output table is empty.   Any advice? I simply need to find a way to extract the grid ID of where the points falls within the grid.     I've included a photo of the spatial join parameters. After the process runs, it simply spits out a new shapefile with no features and an empty attribute table.


How to prevent an object from moving when adding a node label

I am trying to make a vertical column of various moon phases using a macro that generates circles, but when I add a node label to a circle (to designates that it is a full moon) it shifts the circle that contains the label slightly to the right.  \documentclass[leqno,12pt]{article} \usepackage{tikz} \usetikzlibrary{calendar,fpu}  \newcommand{\moon}[2][]{%     \def\lunarage{#2}%     \pgfmathsetmacro\textF{ifthenelse(\lunarage==15,"F","")}     \tikz []{         \draw (0,0) circle [radius=1ex];         \node[color=black] (0,0) {\textF};         %     }% } \begin{document}\noindent%     \foreach \d in {0,1,...,30}{%     \moon[]{\d}  \\   } \end{document}   THANKS for any help!


Calculate $\lim_{n\to\infty} \sum_{k=n}^{2n} \frac{1}{k}$

I am not sure how to approach this question. I tried to move the limit into the sum, but that turns the result to $0$, which is incorrect.


To indicate "a collection of items," do you say "an item collection" or "items collection"? What's the rule?  A quick comparative Google Books search indicates that the  is more common than the , but I don't know if I can trust that as a parameter.


How do I get the Minecraft GUI scale to go back to Auto?

I have been playing Minecraft, and I went into the settings to see what could be changed. I was in display and I saw the GUI scale was set to "Auto", which was fairly large. I cycled through the scales until I got back to auto, but the GUI scale was stuck at normal size and wouldn't allow me to make it large again. I know this isn't such a big problem, but I really like big font and this is a constant bother to me.


Finding the value of $k$ for parallel/orthogonal planes

Given two planes  $\pi_1: (1+k)x-3y+6z-4=0$   $\pi_2: x+(5+k)y+3kz+1=0$  Find the value of $k$ such that $\pi_1$ is parallel to $\pi_2$ and when $\pi_1$ is perpendicular to $\pi_2$


Mark as duplicate, original being deleted and unconsistent dialog showing

I just saw this question:  that had been posted by the same user one hour ago.  I marked as duplicate, but then the OP deleted the original, so now this is what shows off when I click the "close" button:        Without any way to "Retract close vote". Is this the expected behaviour or should my vote to close be reverted?


How do themes provide support for child themes?

One of the requests on themeforest is that themes are required to provide child theme support.  I know what child themes are, although I haven't worked a lot with them, but I would like to know is there something that my theme must have to support child themes?


How to solve "error splicing file" IO while copying files?

I've recently backed up some files on an external hard drive in order to install Ubuntu 12.04.  But when I wanted to copy the backed up files (ex. music files) back to home folder, I'm prompted with this:  error splicing file: input/output error     I'm unable to get my files back on my computer.


How can I improve rendering speeds of a Voxel/Minecraft type game?

I'm writing my own clone of Minecraft (also written in Java). It works great right now. With a viewing distance of 40 meters I can easily hit 60 FPS on my MacBook Pro 8,1. (Intel i5 + Intel HD Graphics 3000). But if I put the viewing distance on 70 meters, I only reach 15-25 FPS. In the real Minecraft, I can put the viewing disntance on far (= 256m) without a problem. So my question is what should I do to make my game better?  The optimisations I implemented:   Only keep local chunks in memory (depending on the player's viewing distance) Frustum culling (First on the chunks, then on the blocks) Only drawing really visible faces of the blocks Using lists per chunk that contain the visible blocks. Chunks that become visible will add itself to this list. If they become invisible, they are automatically removed from this list. Blocks become (in)visible by building or destroying a neighbour block. Using lists per chunk that contain the updating blocks. Same mechanism as the visible block lists. Use nearly no new statements inside the game loop. (My game runs about 20 seconds until the Garbage Collector is invoked) I'm using OpenGL call lists at the moment. (glNewList(), glEndList(), glCallList()) for each side of a kind of block.   Currently I'm even not using any sort of lighting system. I heard already about VBO's. But I don't know exactly what it is. However, I'll do some research about them. Will they improve performance? Before implementing VBO's, I want to try to use glCallLists() and pass a list of call lists. Instead using thousand times glCallList(). (I want to try this, because I think that the real MineCraft doesn't use VBO's. Correct?)  Are there other tricks to improve performance?  VisualVM profiling showed me this (profiling for only 33 frames, with a viewing distance of 70 meters):    Profiling with 40 meters (246 frames):    Note: I'm synchronising a lot of methods and code blocks, because I'm generating chunks in another thread. I think that acquiring a lock for an object is a performance issue when doing this much in a game loop (of course, I'm talking about the time when there is only the game loop and no new chunks are generated). Is this right?  Edit: After removing some synchronised blocks and some other little improvements. The performance is already much better. Here are my new profiling results with 70 meters:    I think it is pretty clear that selectVisibleBlocks is the issue here.  Thanks in advance! Martijn  Update: After some extra improvements (like using for loops in stead of for each, buffering variables outside loops, etc...), I now can run viewing distance 60 pretty good.  I think I'm going to implement VBO's as soon as possible.  PS: All source code is available on GitHub:


Why do some answers have dofollow links while others don't?

Why do some answers have dofollow links - like this one     while others don't (for example, , notice nofollow ) ?


Chart to show reputation points grouped by event type

I would like to request a pie chart to see how a user got his or her reputation. This could be placed on the profile page. Sections could contains percentages like:  14 Questions - 200 points - 28.41% 20 Answers   - 400 points - 56.82%  2 Edits     -   4 points -  0.57%  1 Bonus     - 100 points - 14.20%     Image: artist rendering of a pie. It does not have to look this way. It might even be a chart per tag or even per topic .


Can anyone tell me what is the easiest way to root my phone. I have a Samsung galaxy note 2. And what does it mean to flash a new Rom?


Proof for $\gcd$ being the smallest linear combination of $a,b \in \mathbb {Z}$.

Please vet my approach:  First need prove that for the least positive value combination (let, $l$), it will divide $a, b \in \mathbb{Z}$.   Will use the indirect, or contradiction approach to prove that $l \mid a$.  Similar will extend to $l \mid b$.  So, for $l \nmid a, \exists q, r \in \mathbb {Z}$, s.t. $a = al +r, 0 \lt r \lt l$. Hence, $r = a - q.l = a - q(ax_0 + by_0) = a(1 - qx_0) - qby_0$. So, $r$ is a linear combination of $a, b$ with integer multipliers, let $x,y,$ where $x = 1 - qx_0, y = -qy_0$  The assumed form for $l = ax_0 + by_0$. Given, by contradiction that $0 \lt r \lt l$, have the following inequalities, as the integer multipliers for $r$ must be smaller than of $l$, and positive too:  => $1- qx_0 \lt x_0$ - (i)  & $-q \lt 1$ - (ii)  =>  $1 \lt x_0(1+q)$ - (i)  & $q \gt -1$ - (ii)  Substituting for $q$ from (ii) into (i), get:  $ 1 \lt x_0($negative value$)$ -- obviously false, hence proved that $l  \mid a$ by contradiction.    Addendum In view of responses recd., have modified as follows. First, assume that $a,b \gt 0$. Second, form four cases of possible values of the integer multiplier, and will try to prove by contradiction in each.  Case (i) : $x_0 \gt 0, y_0 \gt 0$ : Have already proved this case above.  Case (ii) : $x_0 \gt 0, y_0 \lt 0$ : Implies $-qy_0 \lt y_0$, but as $y_0 \lt 0$, so cancelling $y_0$ from both sides leads to: $-q \gt 1 => q \lt -1$.  The two inequalities are :  $1 \lt x_0(1+q)$ - (i), $q \lt -1$ - (ii)  Substituting for $q$ from (ii) into (i), get: $1 \lt x_0$(negative value),  again obviously false.  Case (iii) : $x_0 \lt 0, y_0 \gt 0$ : Implies the two inequalities are:  $1- qx_0 \lt x_0$ - (i), $q \gt -1$ - (ii)  $1 \lt x_0(1+q)$, but as $x_0 \lt 0$, so it changes to $-1 \gt x_0(1+q)$, for positive $x_0$. Now, this is also not possible as $(1+q)\gt 0$.  Case (iv) : $x_0 \lt 0, y_0 \lt 0$ : As assume $a, b \gt 0$, so this case is not possible.  Hence, proved for all possible values of $x_0, y_0$.