I am trying to retrieve the href attribute from a link. However, it keeps returning undefined.  This is the html, generated via ajax which I why the .on function does not work in jQuery  html += 'View offer	';   This is the jQuery function    $( ".viewOffer" ).click(function() {  alert($(this).attr('href')); });     Thanks!

I have a bit of code where I am looping through all the select boxes on a page and binding a .hover event to them to do a bit of twiddling with their width on mouse on/off.  This happens on page ready and works just fine.  The problem I have is that any select boxes I add via Ajax or DOM after the initial loop won't have the event bound.  I have found this plugin (), but before I add another 5k to my pages with a plugin, I want to see if anyone knows a way to do this, either with jQuery directly or by another option.


Why does it show 0 in the available column?  [root@server log]# df Filesystem           1K-blocks      Used Available Use% Mounted on /dev/sda2              4128448   4096484         0 100% /   It's an ext3 filesystem.

When I sum up the sizes of my files, I get one figure. If I run du, I get another figure. If I run du on all the files on my partition, it doesn't match what df claims is used. Why are there so many different figures for the total size of my files? Can't computers add?  Speaking of adding: when I add the “Used” and “Available” columns of df, I don't get the total figure. And that total figure is smaller than the size of my partition. And if I add up my partition sizes I don't get my disk size! What gives?


I'm trying to link a pdf to a parcel (see image: ) where you click on one parcel and a specific pdf comes up and if you click on another then a different pdf comes up.   I've got it so far that if you click on a parcel it shows a pdf but the problem is that is shows the same pdf for every parcel!  Is there anyway I can assign it to just one parcel by lets say the objectid?  I'm having trouble setting the action so that it opens each parcel.

I want an attribute in a shapefile named "Link" to add.   The works are all fine but then I would like to add a link in my directory.   This link accesses a PDF. Now, this PDF is not shown.   Is there any other solution or there is nothing to be done?


So, I want to change the selected value of comboBox depending on values I read from my object. This is what I have so far:  public String[] waluta=new String[] {"EUR","PLN","USD"};  public GameEditFrame(int index) {      ...      JComboBox walutaBox = new JComboBox(waluta);     String tmp=main.katalog.gra.get(index).cena.getWaluta();      if (tmp=="EUR" || tmp==null){         walutaBox.setSelectedItem(waluta[0]);     }else if (tmp=="PLN"){         walutaBox.setSelectedItem(waluta[1]);     }else if (tmp=="USD"){         walutaBox.setSelectedItem(waluta[2]);     }      ... }   Sadly, this is not working. Any ideas?    EDIT: SOLVED  Thanks to ZouZou and MadProgrammer comments I've modded previous code. Now it looks like this and it works fine:  public String[] waluta=new String[] {"EUR","PLN","USD"};  public GameEditFrame(int index) {      ...      JComboBox walutaBox = new JComboBox(waluta);     String tmp=main.katalog.gra.get(index).cena.getWaluta();      if (tmp==null)         tmp="EUR";      walutaBox.setSelectedItem(tmp);      ...  }

I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?


For getting Canadian Visa How much money is generally required in order to be sure we are eligible?

My (American) boyfriend wants to come to Canada for 6 months and we had just found out he needs a specific amount of money to visit here to show he can support himself for the 6 months.  How much money will he need? We need help figuring this out because we aren’t exactly sure. He won’t need to pay for anything though. He will be staying with me and won’t need to pay for living or food or entertainment.


Why does LaTex have random capitalisation and letter height? Context: So I'm sure this is a rather random question which probably has a really obvious answer, but since I couldn't find it on this site I've decided that I might as well ask it to quench my curiosity: Question I often see the LaTeX logo written like the following image:  And I've always wondered why this is so? I've also seen it on this site as LaTeX. So:  Why does this site have a capital T and X? Does "TeX" represent something? Why do other sites have a raised A and lowered E? Does that represent anything?  Post - Note Again, apologies if this is an obvious question and has already been asked. If so, please don't downvote, just give me the link to where it has been asked or tell me the answer. Also, I wasn't really sure what to tag this question - "syntax"?

I read many years ago about the meaning of TeX, coming from Greek letters, etc... Also I found many posts here related to the right way to write TeX, LaTeX and so on when it is not possible to use the macro \LaTeX.   But my question is: why are the letters a and e moved on the logo?


I am taking a course in stochastic process this time. As I read through a couple of books every one mentioned that stochastic process is also a random process. So, my confusion is why we  call stochastic process just for a random process? For me random process makes a lot more sense than the stochastic process. I asked this question to my professor too but he replied me "I don't know."

What's the difference between stochastic and random?


This always confused me, as we see during the war of the ring Glorfindel stays at Rivendell and really doesn't do much else, was he sent back in an Istari styled mission in middle earth and was he granted more power. But of all the elves to send back why Glorfindel when the Valar could sent the likes of fingolfin, Ecthelion and so on.  So why was Glorfindel sent to Middle earth and what was his mission?

In the Silmarillion, an elf named Glorfindel is killed in a duel with a Balrog at the battle for Gondolin.  (He kills the Balrog as well.)  Then in The Fellowship of the Ring, an elf named Glorfindel meets Frodo, Sam, Merry, Pippin and Aragorn and helps them get a wounded Frodo to Rivendell. This would be the only time that Tolkien uses the same name for two different elves.  Is there any connection between these two elves?


How to format code in posts on Stack Overflow? I am getting frequent error messages while submitting posts with code. I am getting the following message:  Your Post appears to contain code that is not properly formatted  as code.Please indent all code by 4 spaces using the code toolbar button or the ctrl+k keyboard shortcut.for more editing help , click the ? tool bar icon.  I have tried this by using ctrl+k -->enter code here and entered the code but I am getting the same error message. Also, I have tried using ">" before every line, even then the same message appears.

How do I post text so that it is formatted as code?  What do I need to do so that my code shows up properly — not escaped or removed — when posted? And how to get the correct syntax highlighting?     For more information, see "" in the .


I have an output from R (which is a plain text) that I want to typeset using the listings package. The plain text file involves using special characters like asterisks and quotation marks together and that's where the trouble is happening. Please see the figure below.    For comparison, I typeset the text file using listings package (below) and the verbatim environment (above). You can see that the annotated part differs from the two. How can I fix this?  (FYI: I use XeTeX to compile my documents.)  Here's the MWE:  \documentclass{minimal} \usepackage{listings}  \begin{document}  \textbf{VERBATIM}.  \begin{verbatim} Call: lm(formula = nettfa ~ inc + age, data = subset(data, fsize ==      1))  Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1  Residual standard error: 44.68 on 2014 degrees of freedom \end{verbatim}  \textbf{LISTINGS}.  \begin{lstlisting} Call: lm(formula = nettfa ~ inc + age, data = subset(data, fsize ==      1))  Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1  Residual standard error: 44.68 on 2014 degrees of freedom \end{lstlisting}  \end{document}   Follow up  Adding this code to the preamble solved my problem:  \begingroup % properly typesets UNICODE in listings \catcode0=12 % \makeatletter \g@addto@macro\lst@DefEC{% \lst@CCECUse\lst@ProcessLetter ‘’% *** add Unicode characters *** ^^00% end marker }% \endgroup

I am trying to input code listings with unicode characters and everything seems to work (more or less) except some unicode characters being displayed out of order. For example instead of  służąca do obsługi  I get  łżąsuca do łobsugi  How can I fix that? EDIT: I was asked for providing some code, but unfortunately I doubt it will be any helpful. Basically code like this: \documentclass[11pt,polish]{article}  \usepackage{fontspec} \usepackage{listings} \usepackage{xunicode} \usepackage{xltxtra} \usepackage{babel}  \setmainfont{Charis SIL} % Some font with good unicode support  \begin{document} \begin{lstlisting} służący \end{lstlisting} \end{document}  will output this:  łżą sucy  (yes there is a line break, I don't know where it came from, when I input code in form of a file there are characters out of order, but no line breaks).


I know the code to efficiently overlay one list on another in python, using dictionaries. Here is what i mean:  input:    dictA = {'c':2, 'e':1};   print(dictA);   output:   {'c': 2, 'e': 1}   input:   dictB = {'a':0,'b':0,'c':0,'d':0,'e':0,'f':0};  print(dictB);   output:   {'a': 0, 'b': 0, 'c': 0, 'd': 0, 'e': 0, 'f': 0}   input:   dictB.update(dict(dictA));  print(dictB);   output:  {'a': 0, 'b': 0, 'c': 2, 'd': 0, 'e': 1, 'f': 0}   dictA is overlayed on dictB with the 'c' and 'e' now having the values they were assigned in dictA.  Question: What is the equivalent syntax in C# to overlay one list another as above?

What's the best way to merge 2 or more dictionaries (Dictionary<T1,T2>) in C#? (3.0 features like LINQ are fine).  I'm thinking of a method signature along the lines of:  public static Dictionary<TKey,TValue>                  Merge<TKey,TValue>(Dictionary<TKey,TValue>[] dictionaries);   or  public static Dictionary<TKey,TValue>                  Merge<TKey,TValue>(IEnumerable<Dictionary<TKey,TValue>> dictionaries);   EDIT: Got a cool solution from JaredPar and Jon Skeet, but I was thinking of something that handles duplicate keys. In case of collision, it doesn't matter which value is saved to the dict as long as it's consistent.


I need to find out the arrival to Miami, USA of TAM Flight #8090, from Brasil on July 17 2015.

I'm looking for some old flight stats as Flightaware provides me for the last 4 months. However, I'm looking for flights from the past 5 years. Is there any database that is capable of doing so?  For example, I'm interested in KLM1964 on January 5, 2012.  Specifically, statistics including departure/arrival times, and aircraft type.


I posted an answer to a question, and a user posted a comment that I feel is better handled in chat.  In a previous question, I was prompted to move the comment to chat when it went over a certain limit.  Can I move comments to chat without having hit that limit?

Question: For an answer on a stack exchange site with say 8 comments, how can I / is it possible to import the comments into a chat room? Background: I was helping with a  and made several comments before I saw the link to auto-import comments into a chat room.  This was awesome by the way!! Note that the person who asked the question left a link to the chat room in a comment. I wanted to make a similar chat room  because I edited an answer which wasn't mine and added a paragraph.  I wanted to chat with the answer's author @JonHopkins to say, 'hey feel free to remove my edit -- just wanted to add my $0.02' -- especially as the stack exchange engines said not to add an additional answer.  HOWEVER, there was no link to auto-import the comments -- probably because I hadn't previously left one, but I'm not sure. So I ask here, Stack Exchange Gurus, could a static link be added to auto-import a series of comments into a chat session?


I enabled the large text option in accessibility menu because I have Full-HD screen. The problem is why the setting reverts itself back to "non-large" mode after I restart my PC? It's funny because the switch in settings is set on, but some UI elements like top panel are small but apps like Chrome are enlarged. I use ubuntu 20.04 LTS Can you write me a correct script for that setting so I can paste it to startup applications so it runs when I login into the system. I couldn't find it on internet?

So I was configuring VS code on my Notebook when suddenly I noticed that my interface font got really small on my desktop, terminal and files. I use Gnome Tweaks Tool to increase my scaling factor to 1,15 , but, even though it was active, the font stayed tiny. The solution I found was moving my scaling factor, which instantly fixed my font issue, however, every time I restart my Notebook the font gets tiny again and I have to repeat the process. I tried reseting my font configuration using this command, but had no success. gsettings reset org.gnome.desktop.interface text-scaling-factor  I also tried using the command dconf reset -f /  Finally, I tried using dconf-editor, but still had no success altering the font rendering DPI or changing the scaling factor. All of the steps I mentioned fixed my fonts temporarily, but the issue still persists when I restart my Notebook I am out of ideas and even considered getting a fresh Ubuntu install by now... My video card: NVIDIA GeForce GTX 1050 GPU


Since filecontents is usable into document (LaTeX2e <2019-10-01> patch level 3), the etex package breaks the filecontents new \write...  With TeXLive 2018, the following code is ok:  \documentclass{article} \usepackage{etex} \usepackage{filecontents} \begin{filecontents*}{\jobname-0.vrb} content \end{filecontents*} \begin{document} A \end{document}   With TeXLive 2019 and LaTeX2e <2019-10-01>, the following (equivalent) code is broken:  \documentclass{article} \usepackage{etex} %\usepackage{filecontents} \begin{filecontents*}[force]{\jobname-0.vrb} content \end{filecontents*} \begin{document} A \end{document}   The error message is:   ! No room for a new \write . \ch@ck ...\else \errmessage {No room for a new #3}                                                   \fi  l.4 \begin{filecontents*}[force]{\jobname-0.vrb}

The old environment (before 10/2019)   \usepackage{filecontents}  \begin{filecontents}{tabelle.tex}   ... some text ...  \end{filecontents}`   will overwrite an existing file tabelle.tex.  After my update yesterday in debian sid, it does not work any more.  I removed the \usepackage{filecontents} because the functionality should now be inside the LaTeX kernel.   But filecontents will not overwrite my file (with respective message in log):  LaTeX Warning: File 'tabelle.tex' already exists on the system.                Not generating it from this source.   Trying to force overwrite with  \begin{filecontents}[overwrite]{tabelle.tex} leads to error:   ! LaTeX Error: Trying to overwrite 'kivitendo-print7y2OSd.tex'.   So it looks like it tries to overwrite the encompassing file.  Is this a bug or am I missing a point?  Edited 09.11.2019:  Minimal example:  \documentclass{article} \usepackage{etex} \begin{filecontents}[overwrite]{addfile.tex}     \centering{Hello World!} \end{filecontents} \begin{document}     Just a test. \end{document}   Apparantly, the \usepackage{etex} causes the error. The latex code is used by the web application kivitendo. Within my short test, I see no drawback to eliminate the package 'etex'. After that, for me it's working.


I work in LyX. There's a default macro for the kernel: \ker which has nice spacing if I put something after it, compared to \text{ker}. I'd like to have macros with the same nice spacing for the image, coimage, and cokernel, respectively im, coim, coker.

Mathematical operators, such as function names, should be set in roman type, not italics. Latex already has commands for some operators, including \max, \min, and \log.  How can I define additional such commands?


My code is using the read() function to "read" through a txt file one character at a time and needs to internally count the number of lines, words, and characters.  Definitions of what is considered a line, word, and character:  of characters = any character that is "read" even if it is a 'whitespace' character  of lines = whenever the whitespace character '\n' is read.  of words = whenever a non-whitespace character is read that is either the first word OR one that is preceded by a whitespace character  *** I used Character.isWhitespace() method to determine if the current character is a whitespace or not.   import java.io.*; import java.util.LinkedList; public class UnixCommands{      public int[] wc(Reader in) throws IOException {          int[] result = new int[3];           int countChar = 0;          int countWord = 0;           int countLine = 0;          int savedD = -1;          int data = in.read();           while (data != -1) {               countChar++; //countChar no matter what.             if(data == '\n') { //countLine if '\n' is read.             countLine++;             }              if((countWord == 0 && !Character.isWhitespace(data)) ||              // first word appears           (!Character.isWhitespace(data) && Character.isWhitespace(savedD)))              //anytime another word appear.         {             countWord++;         }           savedD = data;         data = in.read();     }           result[0] = countLine;         result[1] = countWord;         result[2] = countChar;         System.out.println(countLine);         System.out.println(countWord);         System.out.println(countChar);         System.out.println(result);      return result;  }    }  Input: I am giving it a text file. Output:  63852     -> count of lines 562492    -> count of words (i think my number of words is off by 1 word)  3202326    -> count of characters [I@63b719   -> not sure why my result array is outputting this   I guess the question is why is not outputting the appropriate number of words?

In Java, arrays don't override toString(), so if you try to print one directly, you get the className + '@' + the hex of the  of the array, as defined by Object.toString():  int[] intArray = new int[] {1, 2, 3, 4, 5}; System.out.println(intArray);     // prints something like '[I@3343c8b3'   But usually, we'd actually want something more like [1, 2, 3, 4, 5]. What's the simplest way of doing that? Here are some example inputs and outputs:  // Array of primitives: int[] intArray = new int[] {1, 2, 3, 4, 5}; //output: [1, 2, 3, 4, 5]  // Array of object references: String[] strArray = new String[] {"John", "Mary", "Bob"}; //output: [John, Mary, Bob]


How does @Autowired annotation work for a private field without a getter and a setter? How can spring access a private field?

What is reflection, and why is it useful?  I'm particularly interested in Java, but I assume the principles are the same in any language.


A person whose name is written in a death note is immune to all other death notes. Are they immune to a bullet to the head or eating an arsenic cream pie, too? If so, would they have a sort of "luck shield" that stops any potential causes of death from making it impossible to fulfill the death note entry, or would they just survive it?

Suppose I wrote that I will be killed by a UFO falling from space in the year 2315 while I am lifting.  Will the Note increase my lifespan? In other words, will I still be alive by then?


Let $f:D(0,1) \to \mathbb C$ be continuous on the closed unit disc $D(0,1)$ and holomorphic on the open unit disc.  Show that there exist a sequence of polynomial that converge uniformly in the closed unit disc to $f$.  Any help please?

Let $D=\{z:|z|<1\}$.   suppose $f(z)$ is analytic on $D$ and  continuous on $\{z:|z|\leqslant1\}$. prove that there exists polynomial sequence  $\{P_n(z)\}$ such that $\{P_n(z)\}$  converges uniformily to $f(z)$ on  $\{z:|z|\leqslant1\}$


There's a problem that goes as follows:  Let $a_n$ be the number of binary strings of length $n$ in which there are no consecutive 0s. Show that $a_1 = 1, a_2 = 3$ and that $a_n = a_{n-1} + a_{n-2}$  I am not sure how exactly am I supposed to "show" the final bit. Proofs by induction involve the closed formula for $a_n$. Is there a formal, general proof to this or do I have to show using words and possibly figures?

• $C_n =$ this number of bit strings  • A binary string with no adjacent 0s is constructed by   Adding “1” to any string w of length $n-1$ satisfying the condition, or Adding “10” to any string v of length $n-2$ satisfying the condition   I still don't find that intuitive at all. Why adding up $C_{n-1} + C_{n-2}$ results in $C_n$? I have tried my best and asked my friends for help, but they find the formula unintuitive as well. Could anyone here come up with a clear explanation? Thanks!


When I signed up, I encountered some hostility, but it seems to have gone down since I added a personalized image. Do people on here tend to be more hostile toward users who have a default gravatar?

I know this is hard to answer since, to the extent that anyone does this, they likely don't do it consciously. In the spirit of Richard Wiseman and  I just wondered what were people's thoughts on it.  Please bear in mind that that's me in the picture, and if you down-vote this, that'll be a real person hurtin', not some abstract symbol.


I've been trying to work on a program that renders text into a certain area on the command line. I have no idea how to do this. Basically, the user is going to choose a width and a height. I was wanting to use that data to put the text in a certain area of the screen. If you know how to do this please tell me.

I have a console application project in C# 2.0 that needs to write something to the screen in a while loop. I do not want the screen to scroll because using Console.Write or Console.Writeline method will keep displaying text on console screen incremently and thus it starts scrolling.  I want to have the string written at the same position. How can i do this?  Thanks


I was trying to get the model a page is looking to and send data based on the Model received. I have tried the following code but it says 'model' is a variable but is used as a Type  public IActionResult GetComments(string modelName)         { Type model = Type.GetType(modelName+", UHDMS.Models");                 var mapping = _context.Model.FindEntityType(model);                 tablename = mapping.GetTableName();                  var props = _context.Model.GetEntityTypes().Single(e => (e.GetTableName().OfType<model>()).Equals(tablename)).GetProperties();  }   Note: error is happening on this line e.GetTableName().OfType()

What's the best way to call a generic method when the type parameter isn't known at compile time, but instead is obtained dynamically at runtime?  Consider the following sample code - inside the Example() method, what's the most concise way to invoke GenericMethod<T>() using the Type stored in the myType variable?  public class Sample {     public void Example(string typeName)     {         Type myType = FindType(typeName);          // What goes here to call GenericMethod<T>()?         GenericMethod<myType>(); // This doesn't work          // What changes to call StaticMethod<T>()?         Sample.StaticMethod<myType>(); // This also doesn't work     }      public void GenericMethod<T>()     {         // ...     }      public static void StaticMethod<T>()     {         //...     } }


I posted a bounty at  , and in the process broke up what I had to say into three or so separate paragraphs, intended both to distinguish my major points, and give some whitespace instead of a wall of text.  The text of my request is visible at  , but it's a wall of text. Perhaps some people will be sufficiently motivated by a bounty to parse through what my multiple points are, but I regard the undistinguished block as less readable than the whitespace-endowed message I tried to set out clearly to any parties interested in the bounty.  Could bounty requests preserve paragraph delineation the way normal posts do?

Bounties allow us to provide a message along with bounties we place, should we deem it useful to include one. I use this myself regularly, and sometimes a decent explanation is warranted so that readers understand what's going on.  However, bounty messages get their newlines stripped out. This can impede our attempts to make our bounty messages readable and useful. Just now I wrote  a bounty with 3 paragraphs + a footnote on its own line to maximise its legibility (and could type newlines in the bounty message text input), but after submission the message was compacted into the following:    It's especially strange that bounty messages can be a whole three thousand characters long (enough for a junior essay), while not providing us with paragraphs, a basic building block of legibility:    Not that I think I could ever use the whole 3,000 — the message above was just 850.  Could bounty descriptions please leave the newlines I write in them intact?  (Should someone decide to write super-tall bounty messages to abuse this ability, bear in mind moderators can refund bounties; a user making a nuisance is not beyond being acted on.)


The following code get's an error when compiled. I know it's missing something but I just can't figure out what.  public class Books {     String title;     String author;      public static void main(String[] args) {         // TODO Auto-generated method stub          Books[] myBooks = new Books[3];          myBooks[0].title = "Learn Java";         myBooks[1].title = "Java Development";         myBooks[2].title = "Java Today!";         myBooks[0].author = "S";         myBooks[1].author = "Mr. S";         myBooks[2].author = "SN";          int x = 0;         while (x < myBooks.length) {             x = x + 1;             System.out.print(myBooks[x].title);             System.out.print(" by ");             System.out.println(myBooks[x].author);         }      }  }

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


I have a question regarding the nature of the conjunctions "for" and "because".  The former is known to form part of the famous acronym FANBOYS, that encompasses the most common coordinate conjunctions, whilst the latter represents one of the subordinate ones. Still, they appear to share the same semantic properties and express the same relation.  The dude is not coming because he is mad at you - the second clause gives the reason for the dude's not coming => it is dependent;  The duke is not coming, for he is no more - same relationship, only slightly more poetically put => it is dependent.  I'm sure these conjunctions have been "separated" for a good reason, so could you please explain why we consider "for" to be a coordinate conjunction?

Third grade teacher here. I plan to teach students to distinguish between simple, compound and complex sentences — but only if I can demonstrate a clear and meaningful difference between the latter two!  Complex or Compound? Each sentence in the following pairs is similar to its partner.   All dogs are mammals, so huskies are mammals. All dogs are mammals, therefore huskies are mammals. I come bearing soup, for Kate is sick. I come bearing soup, because Kate is sick.   Are the sentences above complex or compound?   First, we need to decide whether each italicized clause is independent or dependent. To me, they all look dependent. If that is the case, there's not much need to teach about compound sentences. Is there a meaningful difference between the sentences in each pair that I am missing? (Are the FANBOYS as special as they'd like to think?)


When I click "HOME" on my Navbar, it shows this, with a little white space underneath: However, I want it to show the full display at the top, without the white space under, like this: How can I fix this issue? Please modify my code to get the desired result and add the modified code in the answer. Here is my html and CSS code:

I'm building a class library that will have some public & private methods. I want to be able to unit test the private methods (mostly while developing, but also it could be useful for future refactoring).  What is the correct way to do this?


I am learning Blender and currently building a simple low poly model. Trying to follow reference picture I realize that it is very difficult to build a model such that all faces are perfectly planar. I can use flattening tool but some quads are never brought to perfect flatness. When tested wih 0.1 deg limit they show nonplanarity.   Even when I scale one face of a standard cube (in its own plane) it is enough to show nonplanarity above 0.01 deg. Similary scaling and/or rotating simple plain is enough to create nonplanarity above 0.02 deg.   I am guessing that this is related to the finite accuracy of numerical representation of the location of vertices. Clearly it makes sense to disregard this level of nonplanarity.   But how about 0.1 deg? 1deg?

I think my question relates to a fundamental of 3D modeling that I haven't picked up on yet. It's very simple:  Let's say I have a flat quad. A plane on the XY plane inserted into am empty blender file is a great example. Now let's say I start moving each of the 4 vertices around on in any direction, especially the Z axis.   At this point, there would still be one face, but its extremely unlikely that the face would be planar (I just learned this word). So blender does its best to make sense of what this should look like.  The problem I'm having is that it seems like my quads are always like this, but they never look the way I want. There are edges and seams that look like they are dangling in space, and what tends to happen is that my mesh looks great when viewed from most angles, but if you look at it from just the right angle, you notice the dangling edges or sometimes even some kind of impossible geometry. And so I might try to nudge the problematic vertices around, but this often seems to either make it worse, or just hide the bad geometry until you see it from a different angle.  For me, this always seems to happen whenever I'm trying to move vertices to add roundness to something that is originally square.   There is another question on here about how to actually flatten the quads. That's great, and I might use some of the techniques mentioned there. My question is:   Why does this happen? (Can someone explain this better?) What are some tips and tricks to avoid this situation? What are some tips and tricks to mitigate this situation?   EDIT Here is an illustration:  The overall mesh as viewed from a distance looks decent (for my skill level)    But if you get closer and look from a certain angle...    Super close up:    The "edge" that is pointed to by the arrow is not actually an edge, but some kind of artifact created when blender tries to show the quad. The way the vertices are positioned, it shouldn't actually be possible to see the sliver of the face that I marked in red, since this face is supposed to be around the corner from the edges. The edges should form the silhouette on the right side of my figure.     Here is the side view. Maybe it is the angled topology that skews the face in a funny way?  But I'm not looking for help with this one particular issue, but rather a better understanding of why this happens, and ideas to prevent this in future models.


I was trying to prove that S3×Z2 is isomorphic to D6 . Well there are a lot of Methods to Do so. But I was Queried that I We know If two ABELLEAN Groups have same no. Of elements of each order then they are ISOMORPHIC Also there exist a Abellean and a NONAbelian group satisfying the property but still non ISOMORPHIC. So my doubt Is -- Is it true If both are NONAbelian And Have same no. Of elements of each order then they are ISOMORPHIC

Suppose $G$ is a finite group and I know for every $k \leq |G|$ that exactly $n_k$ elements in $G$ have order $k$. Do I know what the group is? Is there a counterexample where two groups $G$ and $H$ have the same number of elements for each order, but $G$ is not isomorphic to $H$? I suspect that there is, but I haven't thought of one.


I have a scene set up with several layers. Everything is lit correctly and, when I change the shading mode to rendered, everything's just great. The moment I actually render the image though, only one layer shows up. Is there a control panel for setting the layers to render?

I'm very new to Blender and I have been watching some tutorials on how to make models within it. In every one of these, their render settings (In the properties tab) have a Layers section below the Performance section.   My version of blender does not seem to have that, at least by default. I've looked around the user preferences and haven't found anything. Thanks for helping.


I have a Dual Boot PC with Windows 10 Pro 64 Bit originally and recently added Ubuntu 20.04.2 LTS.  When I am in Windows 10 and Power Off the System Time Holds correctly if I Power on and go back into either Windows or Ubuntu.  When I Power Off from Ubuntu and go back into Ubuntu the System Time Holds correctly.  If I power down from Ubuntu and go into Windows the System Time is ahead by exactly 7 hours.  I am in Phoenix Time Zone which is GMT -7, so it appears to me that it powers on after powering off in Ubuntu and reverts to GMT which would be exactly 7 hours ahead.  I know how to reset the System Date and Time in Control Panel, but would like a permanent fix, if anybody knows how to fix it.

Dual boot system Windows XP Pro and Ubuntu 12.04.  I have the bios set for the correct time and Ubuntu set for US Eastern time.  Ubuntu will boot up and the time will be off by -4 hours.  If I correct the time in Ubuntu then when I boot up in Windows XP the time will be off by + 4 hours.  This is a fresh install of 12.04. I did not have this problem before reinstalling Ubuntu.


My bicycle has a label saying  size 19"  . What is the tire size for my bicycle  and the what is the  inner tube size?

I need to replace a tube in my bike. I know there are many tire sizes. I bought 26', assuming that my bike was that size, and realized when I got home that I didn't even know where to measure from. What is the correct location to measure in order to get the correct size of tubes?


I am a new user of latex, I got a template to write my thesis in Latex. But in this template the section command does allow me to make more sub-sections. with the help of \section and \subsection command I can only go till 3 subsection. For example:   1. Main section 1.1 first subsection 1.1.1 first sub-sub section   but it does not allow me to do this  1.1.1.1 first sub sub sub section   Thanks

I have a document which requires many levels of sectioning. I have sections, subsections and subsubsections, but require one more level below that. I can't change the sections to be parts and move everything up a level, as this document will eventually be included in another document which has parts/chapters already.  I see that the \paragraph command is used for defining the section level below subsubsection, but that doesn't produce headings in the same way that subsection and subsubsection do. Is there any way to either (1) change the \paragraph command so that it works like subsubsection but just adds another number - ie. 1.2.3.4 or (2) create a \subsubsubsection command to do the same thing?


I have heard that too warm a fermentation createds "fusely" beer. What are they and how can I tell if I have this problem?

I'd recently heard of fusel alcohol in a reference that it causes headaches/hangovers.  First what is fusel alcohol, and what creates it (can I avoid it)?  Secondly, is fusel alcohol really the main culprit behind hangovers? I know I stopped making/drinking mead as it was a guaranteed hangover for me the next day.


I've got a complex equation with 4 roots that I am solving. In my calculations it seems like I am going through hell and back to find these roots (and I'm not even sure I am doing it right) but if I let a computer calculate it, it just seems like it finds the form and then multiplies by $i$ and negative $i$. Have a look:   Here's me going bald:

So I'm trying to get this:    And I've calculated $z^4=16 \left( \cos (\frac{- \pi}{3})+ \sin ( \frac{- \pi}{3}) \right)$  So I'm trying to find the roots using the formula:  $ r^{1/n} = \left( \cos ( \frac { \theta + 2 \pi \cdot k}{n}) + i \cdot \sin ( \frac{ \theta + 2 \pi \cdot k}{n}) \right) $  But my result does not equal. Take a look:    This is for $k=0$.  What am I doing wrong?


I have a bash script which activates the anaconda environment and run a python scheduler script and write logs to a file every minute. It is working perfectly fine if I run just the script.  [user@host proj]$ test.sh   After doing ctrl-C, I see the logs are coming every minute.  [user@host proj]$ cat logs/log.log Test job 1 executed at : 2018-10-09 14:16:00.000787 Test job 1 executed at : 2018-10-09 14:17:00.001890 Test job 1 executed at : 2018-10-09 14:18:00.001861   But when I run same script in background with nohup  [user@host proj]$ nohup test.sh & [1] 24884 [user@host proj]$ nohup: ignoring input and appending output to ‘nohup.out’   I can see with top that script and python are running  24949 user  20   0  113172   1444   1216 S  0.0  0.0   0:00.00 test.sh 24952 user  20   0  516332  66644  17344 S  0.0  0.8   0:00.65 python   But I cannot see anything to be written in log file.  Not sure what is going wrong. Any suggestion to guide me in correct direction is highly appreciated.

Is output buffering enabled by default in Python's interpreter for sys.stdout?  If the answer is positive, what are all the ways to disable it?  Suggestions so far:   Use the -u command line switch Wrap sys.stdout in an object that flushes after every write Set PYTHONUNBUFFERED env var sys.stdout = os.fdopen(sys.stdout.fileno(), 'w', 0)   Is there any other way to set some global flag in sys/sys.stdout programmatically during execution?


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?

How to root Samsung Galaxy Note 2? I have no experience with rooting. Model number is GT-N7100. Android-version 4.1.1.


How can I copy around 1000 subfolders each having 4000 images into one single folder named all_images?  I tried the following:  $ cp upload/*/* all_images/   and got the following error:  bash: /usr/bin/cp: Argument list too long   Please note that I tried this on two small subfolders and it worked.

I just asked a  related to how I can count the files of particular extension. Now I want to cp these files to a new dir.  I am trying,  cp *.prj ../prjshp/   and   cp * | grep '\.prj$' ../prjshp/   but they are giving the same error,     bash: /bin/cp: Argument list too long   How do I copy them?


var/log is huge: 4.6GB+. Is it ok to just delete all this stuff? Will it mess up my computer?

Is it possible to have 64.5GB log files in Ubuntu? Can I delete those files? My laptop is dual booted and the Ubuntu partition is only 100GB.


I have Ubuntu 15.04 installed on my machine. Currently terminal error messages are not in English (actually they are in Russian).  For example,  $ mmmm mmmm: команда не найдена   I want to see   $ mmmm mmmmm: command was not found   Solution provided for  does not work for me.

i installed Ubuntu in italian language. Now I would like to see the error commands in english.  For example if i write:     $ mmmm   This is showed:     mmmm: comando non trovato    I would like that      mmmmm: command was not found   is showed.  Any idea?  Regards  Javi


In the following HtmlHelper:  @Html.TextBoxFor(model=>model.Username, new { id = "username", @class = "textbox"})   Some attributes like class have an @ before it while others don't. what does at sign mean there?

Possible Duplicate:          I understand that the @ symbol can be used before a string literal to change how the compiler parses the string.  But what does it mean when a variable name is prefixed with the @ symbol?


I have tried many ways to integrate $\sqrt {\tan x}$ including integration by parts but didn't get to any final result. I also assumed, $$ \tan x = t^2 $$ $$ \int  \sqrt {\tan x} \,dx $$ $$⇒\int \frac{2t^2}{1+t^4}dt$$ but it's getting a bit complicated further, kindly help. Also, are there any simpler ways to integrate this. Answer, $$ \frac{1}{\sqrt 2} \tan^{-1}\left[\frac {\sqrt {\tan x}-\sqrt {\cot x}}{\sqrt{2}}\right] +\frac{1}{2\sqrt 2}\ln\left[\frac {\sqrt {\tan x}+\sqrt {\cot x}-\sqrt {2}}{\sqrt {\tan x}+\sqrt {\cot x}+\sqrt {2}}\right] +C $$

I have been having extreme difficulties with this integral. I would appreciate any and all help. $$ \int \sqrt{\tan x} ~ \mathrm{d}{x}. $$


An event is a 4D point in spacetime. At every point in spacetime there is a tangent space. 4-vectors live in the tangent space. One can contract two events using a metric tensor. Is there a process that moves the event as a point in the manifold to the tangent space?

An entry level confusion about spacetime. I understand that a 4-vector describes a point or event in spacetime. But I've also read (Bertschinger, 1999) that re spacetime "we are discussing tangent vectors that lie in the tangent space of the manifold at each point". If a point/event is described by a single 4-vector, what are all these tangent vectors that lie on the same point? Do they have different co-ordinates to the 'point/event' 4-vector? Could I also ask how a 4-vector 'contains' any sense of direction (I'm thinking here of a vector having direction and magnitude)?


I've just installed 20.04 on my new rpi4 8gb and I'm trying to install ZSH. It should be in the main repo and should be installed with sudo apt install zsh. Unfortunently it throws an error: E: Unable to locate package zsh. I haven't changed anything in my sources.list. my sources.list: ## modifications made here will not survive a re-bundle. ## if you wish to make changes you can: ## a.) add 'apt_preserve_sources_list: true' to /etc/cloud/cloud.cfg ##     or do the same in user-data ## b.) add sources in /etc/apt/sources.list.d ## c.) make changes to template file /etc/cloud/templates/sources.list.tmpl  # See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to # newer versions of the distribution. deb http://ports.ubuntu.com/ubuntu-ports focal main restricted # deb-src http://ports.ubuntu.com/ubuntu-ports focal main restricted  ## Major bug fix updates produced after the final release of the ## distribution. deb http://ports.ubuntu.com/ubuntu-ports focal-updates main restricted # deb-src http://ports.ubuntu.com/ubuntu-ports focal-updates main restricted  ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team. Also, please note that software in universe WILL NOT receive any ## review or updates from the Ubuntu security team. deb http://ports.ubuntu.com/ubuntu-ports focal universe # deb-src http://ports.ubuntu.com/ubuntu-ports focal universe deb http://ports.ubuntu.com/ubuntu-ports focal-updates universe # deb-src http://ports.ubuntu.com/ubuntu-ports focal-updates universe  ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team, and may not be under a free licence. Please satisfy yourself as to ## your rights to use the software. Also, please note that software in ## multiverse WILL NOT receive any review or updates from the Ubuntu ## security team. deb http://ports.ubuntu.com/ubuntu-ports focal multiverse # deb-src http://ports.ubuntu.com/ubuntu-ports focal multiverse deb http://ports.ubuntu.com/ubuntu-ports focal-updates multiverse # deb-src http://ports.ubuntu.com/ubuntu-ports focal-updates multiverse  ## N.B. software from this repository may not have been tested as ## extensively as that contained in the main release, although it includes ## newer versions of some applications which may provide useful features. ## Also, please note that software in backports WILL NOT receive any review ## or updates from the Ubuntu security team. deb http://ports.ubuntu.com/ubuntu-ports focal-backports main restricted universe multiverse # deb-src http://ports.ubuntu.com/ubuntu-ports focal-backports main restricted universe multiverse  ## Uncomment the following two lines to add software from Canonical's ## 'partner' repository. ## This software is not part of Ubuntu, but is offered by Canonical and the ## respective vendors as a service to Ubuntu users. # deb http://archive.canonical.com/ubuntu focal partner # deb-src http://archive.canonical.com/ubuntu focal partner  deb http://ports.ubuntu.com/ubuntu-ports focal-security main restricted # deb-src http://ports.ubuntu.com/ubuntu-ports focal-security main restricted deb http://ports.ubuntu.com/ubuntu-ports focal-security universe # deb-src http://ports.ubuntu.com/ubuntu-ports focal-security universe deb http://ports.ubuntu.com/ubuntu-ports focal-security multiverse # deb-src http://ports.ubuntu.com/ubuntu-ports focal-security multiverse

I'm trying to install libasound2-dev on a freshly installed Ubuntu 20.04 on my Raspberry Pi 4 but apt reports that it can't find the package.  Running apt search libasound2 yields:  ubuntu@ubuntu:~$ sudo apt search libasound2 Sorting... Done Full Text Search... Done alsa-topology-conf/now 1.2.2-1 all [installed,local]   ALSA topology configuration files  libasound2/now 1.2.2-2.1 arm64 [installed,local]   shared library for ALSA applications  libasound2-data/now 1.2.2-2.1 all [installed,local]   Configuration files and profiles for ALSA drivers  ubuntu@ubuntu:~$   Looking at the package repository however, it should be available for arm64:   My /etc/apt/sources.list is below (after removing commented lines).  deb http://ports.ubuntu.com/ubuntu-ports focal main restricted deb http://ports.ubuntu.com/ubuntu-ports focal-updates main restricted deb http://ports.ubuntu.com/ubuntu-ports focal universe deb http://ports.ubuntu.com/ubuntu-ports focal-updates universe deb http://ports.ubuntu.com/ubuntu-ports focal multiverse deb http://ports.ubuntu.com/ubuntu-ports focal-updates multiverse deb http://ports.ubuntu.com/ubuntu-ports focal-backports main restricted universe multiverse deb http://ports.ubuntu.com/ubuntu-ports focal-security main restricted deb http://ports.ubuntu.com/ubuntu-ports focal-security universe deb http://ports.ubuntu.com/ubuntu-ports focal-security multiverse   If it helps, it seems like this problem isn't specific to libasound2-dev. It seems that apt can't find anything in the libdevel section.


I can no longer access my regular administrator account on my Ubuntu (see ) however I really need to access my files. I can only get on the PC with a guest login. How can I access my files? How can I log in as a guest, then using the shell after typing CTRL+ALT+F3 access the files?  This is NOT a duplicate of the suggested question. The person who claimed that it was apparently did not read my previous question linked above.

I'm working on a Ubuntu system, and my client has completely forgotten his administrative password. He doesn't even remember entering one; however it is there.  I've tried the suggestions on the website, and I have been unsuccessful in deleting the password so that I can download applets required for running some files. Is there a solution?


Here is my split equation:  \documentclass{article} \usepackage{amsmath} \begin{document} \begin{equation} \begin{split} a_{ijk} =& \frac {Pr(M_{I} =2  \&  M_J=1 \& M_K =1 | I=i , J=j , K=k)}{Pr (M_I =1 \& M_J =1 \& M_K=1 | I=i , J=j)} \\             =& \frac {\mu_{ijk211}}{\mu_{ijk111}}\\ \end{split} \end{equation} \end{document}   I want to align this equation to the left. Is this possible in an equation environment?


I am fairly new to blender but I keep running into the same problem when using cycles. The noise is unbearable and I can't seem to find the reason. I followed every advice I could find through google and it all seems to make it worse. If you are interested I have a completed render that I tried to create.   If anyone can help me I would be extremely grateful.  UPDATE: I would like to start by saying thank you for the links and the advice. I have been spending my time just messing around with blender settings and got the noise to clear using a combination of denoising and turning off refractive caustics. I'm not sure how the disabling of refractive caustics helped, but oh well. I have been able to drastically improve the quality of the image, but I would say that it still looks poor quality, but I think I'll look for other questions regarding this issue first. Here is what the finished product looks:

I know that this question is a bit old or maybe overdone, but I'm running the latest edition of Blender and when I use the Cycles engine I get really fuzzy results and I can't find a simple, non-compromising solution to the quality.  I don't know exactly what I'm doing wrong here, but I'm sure others share my frustration.  Leaving everything in default settings, I started a new project and switched to the Cycles render.  I duplicated the cube and set colors for two Diffuse BSDF shaders, then went ahead and made walls and a floor all sharing the same diffuse shader.  I made two windows to emit blue light.  The screenshot has gaps between the walls because of the setup:  I'm aware that it's considered very incomplete and many have come to terms with some amount of noise, but is this normal?  Furthermore, with default settings or not, I can't change the amount of noise produced.  Supposedly, using "progressively refine" in the rendering tab should make it refine itself indefinitely, however Cycles only counts to 10 refines and then stops, creating a render which is a pixel-perfect match of the ordinary rendering method when it's completed.  I understand that there are tricks that can be used to reduce noise, but at the cost of extra processing time and usually small quality conflicts, like blurring.  My question essentially boils down to is this Cycles' current limit?


I would like to import an obj file and export it as an fbx file without having to use the Blender GUI. The command: blender --background --python myscript.py Is not working for me from Terminal on mac. My first real problem is I'd like to be able to do anything (even open blender using .exe) using Terminal. I've tried including the path to the Blender app but nothing seems to be working and I am just given the error "blender is not a command"

I need to convert a batch of .obj models to .fbx  I'm using Autodesk 2013 FBX Converter GUI. Is it possible to do it from the terminal? I haven't been able to find much.  Thanks!  ============== EDIT ==============  Thanks for the replies, I think I need to go into more detail.   I'm writing a blender script to do some changes to a model then automatically export that model to both .obj and .fbx   The .obj export works like a charm, but the blender fbx exporter has some problems.  1) It can't embed all the media so I need to relink textures  2) The scale/rotation is off   But, I found that if I use the fbx converter on the .obj model I exported it looks great, so I was wondering if I could automate that conversion from my addon.


I fail to find a way to typeset a stack of unrelated equations. As an example, I would like to have these two unrelated equations one under the other: ax+by+c=0 and E=mc^2. I could go for \begin{align}...\end{align} but there is no particular reason to align them against something. I tried to break them via \\ in a \begin{equation}...\end{equation} environment but this is not taken into account (the equations are concatenated in one line). I tried \begin{multiline}...\end{multiline} and \\ but it breaks the equations and justify them one to the left and one to the right. I finally broke them into two \begin{equation}...\end{equation} but they are too much spaced vertically. Is there a simple "multiline left justified" environment I could use? As a workaround, if there are no straightforward solutions I will probably go for align.

align environment without any explicit alignments points (given by &) right justifies the equations in the block. They can be left justified by putting & at the beginning of each equation. Is there any way to left justify them without starting &-s? Maybe some special environment or option? It seems to be an extra work to tell the compiler again and again that I want left alignment on each line.


I have a figure float with 3 subfigs in lyx which are too large to fit on one page, so am using \ContinuedFloat. The figure now goes over two pages and the figure number is the same for both, as in the screenshot.  How can I modify the second figure legend (which is a duplicate of the first) to simply read: "Figure 4 (continued)" or something similar, such that I don't have two duplicate figure legends? Is it possible through \renewcommand somehow?

%This is figure 1         \begin{figure}           \centering           \caption{blahblah}           \label{figure1}          \vspace{0.5 cm}          \begin{center}         \fontsize{10pt}{12pt}\selectfont Panel A         \end{center}         \includegraphics[scale=0.8]{s1.pdf}          \vspace{1 cm}          \begin{center}         \fontsize{10pt}{12pt}\selectfont Panel B         \end{center}         \includegraphics[scale=0.8]{s2.pdf}           \end{figure}           %This is Figure 1 continued         \begin{figure}         \vspace{-1.8cm}           \centering           \caption{blahblah}           \label{figure1cont}          \vspace{0.5 cm}          \begin{center}         \fontsize{10pt}{12pt}\selectfont Panel C: Bank $\Delta$\textit{CoJPoD}         \end{center}         \includegraphics[scale=0.8]{s3.pdf}          \vspace{8 cm}           \end{figure}   %This is figure 2 \begin{figure}   \centering   \caption{blahblah}   \label{figure2}  \vspace{0.5 cm}  \begin{center} \fontsize{10pt}{12pt}\selectfont Panel A \end{center} \includegraphics[scale=0.8]{s4.pdf}  \vspace{1 cm}  \begin{center} \fontsize{10pt}{12pt}\selectfont Panel B \end{center} \includegraphics[scale=0.8]{s5.pdf}  \end{figure}     When I use the above, I get my first figure is called Figure 1, however the second figure (which is meant to be called Figure 1 (Cont.)) appears as Figure 2 on the next page and the final figure (which is meant to be called Figure 2) appears as Figure 3.  I also tried using subfig package with \ContinuedFloat:          %This is figure 1         \begin{figure}           \centering           \caption{blahblah}           \label{figure1}          \vspace{0.5 cm}          \begin{center}         \fontsize{10pt}{12pt}\selectfont Panel A         \end{center}         \includegraphics[scale=0.8]{s1.pdf}          \vspace{1 cm}          \begin{center}         \fontsize{10pt}{12pt}\selectfont Panel B         \end{center}         \includegraphics[scale=0.8]{s2.pdf}           \end{figure}           %This is Figure 1 continued         \begin{figure}         \vspace{-1.8cm}           %Using ContinuedFloat here         \ContinuedFloat           \centering           \caption{blahblah}           \label{figure1cont}          \vspace{0.5 cm}          \begin{center}         \fontsize{10pt}{12pt}\selectfont Panel C: Bank $\Delta$\textit{CoJPoD}         \end{center}         \includegraphics[scale=0.8]{s3.pdf}          \vspace{8 cm}           \end{figure}   %This is figure 2 \begin{figure}   \centering   \caption{blahblah}   \label{figure2}  \vspace{0.5 cm}  \begin{center} \fontsize{10pt}{12pt}\selectfont Panel A \end{center} \includegraphics[scale=0.8]{s4.pdf}  \vspace{1 cm}  \begin{center} \fontsize{10pt}{12pt}\selectfont Panel B \end{center} \includegraphics[scale=0.8]{s5.pdf}  \end{figure}   But all this does is it makes my first figure called "Figure 1", then my Figure 1 continued figure is named as "Figure 0" and the figure that's meant to be my Figure 2 called Figure 1.  Any help would be appreciated.


In JavaScript, you can declare all the keys and value combinations for a JSON object in one go as follows...  var myJSON = {     'key1' : 'value 1',     'key2' : 'value 2',     'key3' : 'value 3',     'key4' : 'value 4',     'key5' : 'value 5',     'key6' : 'value 6' };   I was wondering whether we can do something similar in Java for HashMaps.  HashMap<String, String> map = new HashMap<String, String>(     "Key 1", "Value 1",     "Key 2", "Value 2",     "Key 3", "Value 3" );   Basically, I need this as a one time read only thing as Config for the other parts of my code. I searched and tried a few solutions, but was not able to make them work. Or is there a better approach that I can do?

How would you initialise a static Map in Java?  Method one: static initialiser  Method two: instance initialiser (anonymous subclass) or some other method?  What are the pros and cons of each?  Here is an example illustrating the two methods:  import java.util.HashMap; import java.util.Map;  public class Test {     private static final Map<Integer, String> myMap = new HashMap<>();     static {         myMap.put(1, "one");         myMap.put(2, "two");     }      private static final Map<Integer, String> myMap2 = new HashMap<>(){         {             put(1, "one");             put(2, "two");         }     }; }


I'm trying to implement the method fibCalc2 for calculation of nth Fibonacci number, but I'm getting the null pointer exception and I don't know how to go further. Is my solution make sense? Any help will be appreciated.  Note: HashTableMap is also implemented by myself, so it is different from the Java's implementation.  Update: NullPointerException on the last line of the code  Here is the code:  private static int callCount2; private static Map<Integer, Long> ansMap = new LLQHashTableMap(10);    public static long fibCalc2(int n) {     if(n == 0 ||n == 1) return n;     if(ansMap.getSize() <= 2){         ansMap.define(0, (long) 0);         ansMap.define(1, (long) 1);     }     long tempVal1, tempVal2;     try {         long temp = ansMap.remove(n);         ansMap.define(n, temp);     } catch (Exception ex){          try {             long temp = ansMap.remove(n-1);             ansMap.define(n, temp);             tempVal1 = ansMap.getValue(n-1);         } catch (Exception ex1){             tempVal1 = fibCalc2(n-1);         }         try {             long temp = ansMap.remove(n-2);             ansMap.define(n, temp);             tempVal2 = ansMap.getValue(n-2);         } catch (Exception ex1){             tempVal2 = fibCalc2(n-2);         }         ansMap.define(n, tempVal1+tempVal2);     }     callCount2++;     return ansMap.getValue(n); }   interface of my Map:  package adt;  import impl.KeyValuePair;  /**  * A generic map  * @param <K>  * @param <V>  */ public interface Map<K, V> {      /**      * Adds a new key-value mapping to the map, which will      * replace a previous key-value mapping that has the      * same key, if it exists      *      * @param key of the key-value pair to be added      * @param value of the key-value pair to be added      */     public void define(K key, V value);      /**      * Returns the value associated with the given key      * in the map, if one exists, or null if the key is       * not in the map      *      * @param key whose value we want to return      * @return value associated with the given key      */     public V getValue(K key);      /**      * Removes the key-value pair from the map that has      * the given key value, and returns the associated value       * if it exists; if the key is not in the map, the map      * remains unchanged, and null is returned      *      * @param key of the key-value pair that we want to remove      * @return value associated with the given key before removal      */     public V remove(K key);      /**      * Removes and returns some key-value pair from the map,       * if the map is not empty; if the map is empty, an       * exception is thrown      *      * @return some key-value pair from the map      * @throws Exception if the map is empty      */     public KeyValuePair<K, V> removeAny() throws Exception;      /**      * @return the number of key-value pairs in the map      */     public int getSize();      /**      * Removes all key-value pairs from the map      */     public void clear();      /**      * @return a String representation of the map      */     @Override     public String toString(); }

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


I have recently been noticing many people using "learn" as a synonym for "teach", as in      Mr. Smith learned you how to do long division.    How common is this? Is it considered "correct"? It sounds strange to me. Google lists this usage as the second definition of "learn", and as both archaic and informal.

With seemingly increasing frequency I come across a phrase using 'learn' when I think it should be 'teach'.  The classic example is 'that will learn them!', as in "Shoot all criminals - that will learn them!". I thought this was being deliberately wrong for comedic effect, in keeping with the general sentiment of the sentence.  Another example from a Stack Exchange site (http://programmers.stackexchange.com/questions/53880/stuff-you-should-have-learned-in-school-but-didnt-pay-attention-to-at-the-time)     I don't know if you can learn someone   to write at this age   Am I being overly fussy/old fashioned or is this just wrong?


I have just started studying implication in mathematics. So, you'll probably have an idea of where my confusion lies right from the get go.  In the truth table, where $A \implies B$ we obtain this result:  A   B   T/F ___________ T | T | T T | F | F F | T | T F | F | T   Now, my confusion here is regarding why $A\implies B$ given A is false, and B true. The others I understand. The first and last one are obvious, the second one implies, to me anyway, that given A implies B, the truth of B rests upon the truth of A, B is false, A is True, which cannot be, thus not B given A is false.  Now... then, why is B true despite the fact that A is false? Or rather, why is the statement B given not A, True. The truth of B is implied from the truth of A, but A is a false statement. So it's very contradictory that this may be, and in fact, if you go through a real life example, you would find that the third statement seems to be false.  Say $A$ is the statement that it is dark outside, and $B$ the statement that the sun is not on our side of the earth. If it is not dark outside, than stating that the sun is on the other side of the planet must be wrong (in my example i'm going to claim that the sun is the only light source).  Side note:  I just had a thought, if A is false, does that mean you can conclude... mmm, whatever? I mean, B is implied via the truth of A, if A is false, B is NOT implied, but then B could be EITHER true or false, I suppose. Is this correct?  However, would that not mean that A does not imply anything when false. Would that not set the 3rd and 4th statement to be undefined?

I am studying entailment in classical first-order logic.  The Truth Table we have been presented with for the statement $(p \Rightarrow q)\;$ (a.k.a. '$p$ implies $q$') is: $$\begin{array}{|c|c|c|} \hline p&q&p\Rightarrow q\\ \hline T&T&T\\ T&F&F\\ F&T&T\\ F&F&T\\\hline \end{array}$$  I 'get' lines 1, 2, and 3, but I do not understand line 4.      Why is the statement $(p \Rightarrow q)$ True if both p and q are False?  We have also been told that $(p \Rightarrow q)$ is logically equivalent to $(~p || q)$ (that is $\lnot p \lor q$).  Stemming from my lack of understanding of line 4 of the Truth Table, I do not understand why this equivalence is accurate.       Administrative note. You may experience being directed here even though your question was actually about line 3 of the truth table instead. In that case, see the companion question  And even if your original worry was about line 4, it might be useful to skim the other question anyway; many of the answers to either question attempt to explain both lines.


I have association bonus on superuser.com. After that I've started a bounty worst of 50 rep and earned more than 10 rep. Now I have 89 rep (38 of which is earned at superuser which is more than 10) but still not able to answer protected questions.  So, currently new user with 10 rep can answer protected question and I with 89 (38) rep can't.   How does it work now: after registration on new Stack Exchange site you get 101 rep Association Bonus and are able to answer protected questions only when you have 111+ rep on that site. How should it work: after registration on new stackexchange site you get 101 rep Association Bonus and are able to answer protected questions only when you have earned 10+ rep on that site.

I was reading  last night. When I got to the bottom, where the answer button usually is, I saw the following message in its place:     protected by Won't Jun 13 '11 at 16:28      Thank you for your interest in this question. Because it has attracted   low-quality answers, posting an answer now requires 10 reputation on   this site.      Would you like to answer one of these unanswered questions instead?   I wasn't planning on answering it, but it did make me curious as I have 101 rep on the site. Is this a bug, or is there something I am missing?


I am curious as to how the original log tables were generated. How did they determine that log base 10 of 7 were approximately 0.845...  I've seen various hand calculations of square roots and sine and come up with my own and I have found they help me understand the nature of those functions. I was wondering if I could strength my intuitions of logs beyond the simple notion of what exponent raises the number to the correct value.

Henry Briggs compiled the first table of base-$10$ logarithms in 1617, with the help of John Napier.  My question is: how did he calculate these logarithms? How were logarithms calculated back then?  I've found   to be fairly useful, but they don't seem to say much in the way of what I'm looking for. Any answers or useful references would be appreciated.


When working on a new linux machine, are there any command that I can use to get the generic information of the system, e.g.,  the version of the installed linux system, the kern

I have always found it difficult to find information about the system itself in Unix, whether it be   Which OS I am using (version number and all, to compare it with the latest available builds)? Which Desktop Environment am I using? If I am using KDE, most of the programs begin with a K and I can say I am using KDE, but there should be some way to query this, say from a script. Which kernel version am I using? (For example, I am using Fedora, and I want to know what Linux kernel version I am using)   Basically, what I miss is a single point/utility that can get all this information for me. Most of the times the solutions to the above would themselves be OS specific. Then, you are stuck.


I don't have any device with Windows 10 installer and I need to download media creation tool. I entered  of Microsoft, It shows me only ISO file to download. I searched for media creation tool in Google ( Maybe Microsoft has subpage for downloading it. ) but all results are from . I can't trust these web sites ( Maybe they will download media creation tool that install patched / edited Windows ( Not original ). ). Is there a way to download it from original source? I tried ISO file so much but it is not working on my computer. ISO file is not booting but when I directly write Windows to my USB Stick with media creation tools, it works. I'm not asking how to create a Windows 10 bootable USB, I'm asking for how to download media creation tool, I need it.

I'd like to create a Windows bootable USB stick, but I don't have a Windows machine with me at the moment to do so. How could I achieve the same using Ubuntu?


Bluetooth is not working in ubuntu.  isluser@isluser-Vostro-460:~$ lsb_release -a; uname -a; lspci; lsusb No LSB modules are available. Distributor ID: Ubuntu Description:    Ubuntu 18.04.3 LTS Release:    18.04 Codename:   bionic Linux isluser-Vostro-460 4.15.0-70-generic #79-Ubuntu SMP Tue Nov 12 10:36:11 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux 00:00.0 Host bridge: Intel Corporation 2nd Generation Core Processor Family DRAM Controller (rev 09) 00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) 00:16.0 Communication controller: Intel Corporation 6 Series/C200 Series Chipset Family MEI Controller #1 (rev 04) 00:1a.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 (rev 05) 00:1b.0 Audio device: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller (rev 05) 00:1c.0 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 1 (rev b5) 00:1c.3 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 4 (rev b5) 00:1d.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1 (rev 05) 00:1f.0 ISA bridge: Intel Corporation H67 Express Chipset LPC Controller (rev 05) 00:1f.2 SATA controller: Intel Corporation 6 Series/C200 Series Chipset Family 6 port Desktop SATA AHCI Controller (rev 05) 00:1f.3 SMBus: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller (rev 05) 02:00.0 Ethernet controller: Broadcom Inc. and subsidiaries NetLink BCM57788 Gigabit Ethernet PCIe (rev 01) Bus 002 Device 004: ID 413c:2003 Dell Computer Corp. Keyboard Bus 002 Device 003: ID 046d:c05a Logitech, Inc. M90/M100 Optical Mouse Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 004: ID 0a5c:22be Broadcom Corp. BCM2070 Bluetooth 3.0 + HS Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub isluser@isluser-Vostro-460:~$  isluser@isluser-Vostro-460:~$ dmesg | grep -i blue [   17.420176] Bluetooth: Core ver 2.22 [   17.420198] Bluetooth: HCI device and connection manager initialized [   17.420202] Bluetooth: HCI socket layer initialized [   17.420204] Bluetooth: L2CAP socket layer initialized [   17.420215] Bluetooth: SCO socket layer initialized [   17.725981] Bluetooth: hci0: BCM: chip id 73 [   17.726898] Bluetooth: hci0: BCM: features 0x07 [   17.742890] Bluetooth: hci0: isluser-Vostro-460 [   17.743887] Bluetooth: hci0: BCM20702B0 (002.001.014) build 0000 [   17.796223] bluetooth hci0: Direct firmware load for brcm/BCM20702B0-0a5c-22be.hcd failed with error -2 [   17.796228] Bluetooth: hci0: BCM: Patch brcm/BCM20702B0-0a5c-22be.hcd not found [   25.370311] Bluetooth: BNEP (Ethernet Emulation) ver 1.3 [   25.370313] Bluetooth: BNEP filters: protocol multicast [   25.370316] Bluetooth: BNEP socket layer initialized [  961.383186] Bluetooth: hci0: BCM: chip id 73 [  961.384184] Bluetooth: hci0: BCM: features 0x07 [  961.400182] Bluetooth: hci0: BCM20702B [  961.401102] Bluetooth: hci0: BCM20702B0 (002.001.014) build 0000 [  961.401128] bluetooth hci0: Direct firmware load for brcm/BCM20702B0-0a5c-22be.hcd failed with error -2 [  961.401131] Bluetooth: hci0: BCM: Patch brcm/BCM20702B0-0a5c-22be.hcd not found [  961.508567] Bluetooth: RFCOMM TTY layer initialized [  961.508575] Bluetooth: RFCOMM socket layer initialized [  961.508583] Bluetooth: RFCOMM ver 1.11 [ 1623.133664] Bluetooth: hci0: inquiry failed: status 0x12   where can i get BCM20702B0-0a5c-22be.hcd file ?

Bluetooth is on but can't find or be found by any other devices.  Output of sudo service bluetooth status:  ● bluetooth.service - Bluetooth service    Loaded: loaded (/lib/systemd/system/bluetooth.service; enabled; vendor preset: enabled)    Active: active (running) since ხუთ 2015-06-04 22:33:18 GET; 13min ago  Main PID: 26678 (bluetoothd)    CGroup: /system.slice/bluetooth.service            └─26678 /usr/sbin/bluetoothd -n  ივნ 04 22:39:14 Rangoo bluetoothd[26678]: Endpoint registered: sender=:1.63 path=/MediaEndpoint/BlueZ4/HFPAG ივნ 04 22:39:14 Rangoo bluetoothd[26678]: Endpoint registered: sender=:1.63 path=/MediaEndpoint/BlueZ4/HFPHS ივნ 04 22:39:14 Rangoo bluetoothd[26678]: Endpoint registered: sender=:1.63 path=/MediaEndpoint/BlueZ4/A2DPSource ივნ 04 22:39:14 Rangoo bluetoothd[26678]: Endpoint registered: sender=:1.63 path=/MediaEndpoint/BlueZ4/A2DPSink ივნ 04 22:39:14 Rangoo bluetoothd[26678]: bluetoothd[26678]: Endpoint registered: sender=:1.63 path=/MediaEndpoint/BlueZ4/HFPAG ივნ 04 22:39:14 Rangoo bluetoothd[26678]: bluetoothd[26678]: Endpoint registered: sender=:1.63 path=/MediaEndpoint/BlueZ4/HFPHS ივნ 04 22:39:14 Rangoo bluetoothd[26678]: bluetoothd[26678]: Endpoint registered: sender=:1.63 path=/MediaEndpoint/BlueZ4/A2DPSource ივნ 04 22:39:14 Rangoo bluetoothd[26678]: bluetoothd[26678]: Endpoint registered: sender=:1.63 path=/MediaEndpoint/BlueZ4/A2DPSink ივნ 04 22:39:14 Rangoo bluetoothd[26678]: Adapter /org/bluez/26678/hci0 has been enabled ივნ 04 22:39:14 Rangoo bluetoothd[26678]: bluetoothd[26678]: Adapter /org/bluez/26678/hci0 has been enabled   Output of lsusb:  Bus 003 Device 005: ID 0a5c:21d7 Broadcom Corp. BCM43142 Bluetooth 4.0   How can I fix it?


I know that to define a homomorphism between cyclic groups, we only need to determine where the generator goes to. But any smart general idea to determine which choice can send zero to zero?

Is it true that the number of homomorphisms between any two finite cyclic groups of order $m\,\&\,n$ is $\gcd(m,n)$?  I have posted an answer which I believe is true, just wanted to know different approaches to this problem.


My 2-and-a-half-year-old child refuses to take her food. We have to force her to eat. I even tried changing her food to suit her tastes but still need to force her. Please help.

It's becoming more frequent that my 18 month old daughter has started refusing the dinner we give her without trying it. Our best guess at why, is because it contains green things.   We always check the food and it is damn tasty, and she does like it if she tries it, but obviously explaining this to an 18 month old is difficult.  We know she is hungry, because in the past we have given her a replacement of something like toast and she'll gobble that down.  What is the best way to handle this? We don't want her to think that she can always swap her healthy dinner for toast, so the method we have currently been using is, if after 15 minutes she is still not eating, we'll get her down and say something like "You haven't eaten your dinner, you must not be hungry". If, later she decides she does want the food, we'll put here back on her chair and let her eat.  Is this a good way to handle it? Would there be a better method? We don't want her to grow up having "food issues"


I am trying to figure out why my reference is not being cited properly and it's been cut off. It looks like that:    The reference should look like that-> "(Harvard T.H. Chan School of Public Health (2012)". Since I am new to LaTeX, I would appreciate any advice! Thank you! P.S.: I use natbib for bibliography management   \usepackage[round]{natbib}    main.tex file:  \documentclass [oneside, a4paper, openany]{book}  \usepackage[utf8]{inputenc} \usepackage[british]{babel} % Use British english for hyphenation etc \usepackage{tocbibind} % Auto add Bibliography etc to Table of Contents \usepackage[round]{natbib} % Use BibTeX for bibliography management \usepackage{graphicx} \usepackage{hyperref} % Create hyperlinks within text \usepackage[toc,nonumberlist,nopostdot]{glossaries}  \begin{document}  \chapter{Literature Review} \label{Chapter:Literature-Review}  The next section will discuss the consequences of SB and the suggested amount of physical activity per day \citep{harvardthchanschoolofpublichealth2012}.  \bibliographystyle{plainnat} \bibliography{bibliography} \end{document}   bibliography.tex file:  @misc{harvardthchanschoolofpublichealth2012, author = "Harvard TH Chan School of Public Health", organization = "The Nutrition Source", title = "Measuring physical activity", url = "https://www.hsph.harvard.edu/nutritionsource/mets-activity-table/", urldate = "2016-11-09", year = "2012", month = "09", day = "18" }

I'm having a problem with author display for a statute - the author is 'City and County of San Francisco' but the output (using the apalike.bst style file provided by Elsevier) gives the author as 'City and San Francisco', missing the 'County' in the authorname.  Any suggestions?


Is ed25519 quantum resistant? I am using ed25519 as a cryptographic primitive for decentralized identity platform, thus this very crucial question.

Does the application of Shor's algorithm in any way relate/affect the schnorr signature in ed25519?


I am working on PostGIS where I have a two tables. Let's call them A and B. A is coming from a multi polygons layer. B is coming from a multi points layer.  I have created a new column "min_distance" in A. I would like this column to take the value of the distance between the current polygon (eg the own of the row) and the closest point in the table B.  I am thinking about a "for" loop and using the ST_Distance() function but I am honestly lost about how to implement it. My question is : How can I do this ?  By the way, I am also searching for a clear tutorial about PostgreSQL programing.

Say I have table gps like:  CREATE TABLE gps(    gps_id serial primary key,    measured_timestamp timestamp,     geom Geometry(Point,4326),    stop_id int --Null );   And I have a table of stops like:  CREATE TABLE stops(    stop_id serial primary key,    geom Geometry(Point,4326) );   If I want to do an UPDATE on gps to find the nearest stop to each point, is there a way to use a LATERAL query?  I tried something like  UPDATE gps SET stop_id = nearest.stop_id FROM LATERAL(SELECT stop_id FROM stops ORDER BY stops.geom <-> gps.geom LIMIT 1) nearest   but that told me   ERROR:  invalid reference to FROM-clause entry for table "gps"                                                ^ HINT:  There is an entry for table "gps", but it cannot be referenced from this part of the query.   So is the only way to do?  UPDATE gps SET stop_id = nearest.stop_id FROM (SELECT gps.gps_id, stop_id        FROM gps       LATERAL JOIN (SELECT stop_id FROM stops ORDER BY stops.geom <-> gps.geom LIMIT 1) stops) nearest WHERE nearest.gps_id = gps.gps_id   This feels like joining the same table to itself, which wouldn't need to happen with a SELECT INTO


I've just upgraded to 18.04 from 16.04 and am having a problem enabling HTTP/2 on my websites. First of all, my websites all use HTTPS.  I have done the following:  sudo a2enmod http2   added the following text to /etc/apache2/apache2.conf  Protocols h2 h2c http/1.1   and finished off with:  sudo systemctl restart apache2   As far as I am aware, that is all I need to do but none of my sites are working with HTTP/2 after doing the above operations. Can anyone lend a hand as to what I might be doing wrong, please?  Edit: I figured out what the problem was. I was using mod_php and mpm-prefork but in order to support HTTP/2 I needed to be using mpm_event and php7.2-fpm. I did this and got the sites working with HTTP/2 but now I have another problem. php7.2-fpm is timing out when I tried to start up upon reboot resulting in a 503 server error and I have no idea why it is timing out at all.

I am trying to update my apache2 (Apache/2.4.29 (Debian 8)) server to support http2 but after enabling http2   with following code, it does not work because of mpm_prefork does not support http2  <IfModule http2_module>     ProtocolsHonorOrder On     Protocols h2 h2c http/1.1 </IfModule>    since mpm_prefork apache (2.4.29)  does not work with http2, I tried using  mpm_event/mpm_worker but it does not work, so I enable mpm_prefork  sudo a2dismod mpm_event  sudo a2dismod mpm_worker  sudo a2enmod mpm_prefork   Since I am still running php5 what should I do to have http2 support on Debian8?  Will I have to update php5 to php7?  Is there any workaround to use mpm_worker/mpm_event with php5 with http2 support?  apache error log  [http2:warn] [pid 11992] AH10034: The mpm module (prefork.c) is not supported by mod_http2. The mpm determines how things are processed in your server. HTTP/2 has more demands in this regard and the currently selected mpm will just not do. This is an advisory warning. Your server will continue to work, but the HTTP/2 protocol will be inactive. [mpm_prefork:notice] [pid 11992] AH00163: Apache/2.4.29 (Debian) OpenSSL/1.1.0g configured -- resuming normal operations [core:notice] [pid 11992] AH00094: Command line: '/usr/sbin/apache2'


I've started modeling a character in Blender. The goal is to model half of the character on one side of the origin and use the mirror modifier to duplicate the mesh on the other side of the x-axis. I also want to enable smooth shading and add a subdivision modifier so that I can get an idea of what the character will look like later when I apply them. However, somewhere along the line, I must have done something incorrectly because now I have seams showing up in certain sections of the mesh:  Things I have already tried:  Mesh →Clean Up →Merge by Distance Ensuring that bevel weight and crease are set to $0$ for the edges Screaming into the void  Sadly, none of this helped. What can I do to make the seams disappear? Here's a copy of the .blend file:

was following a tutorial where I stumbled into this weird line in my mirrored mesh (sorry for the feet lol)      You can also download the blender file


I have a question on angles expressed in term of radian versus angles expressed in term of degree, which I would like to elevate them into abstract algebra:  (1) Why engineering math uses radian instead of degree? Judging from the way Calculus textbooks very casually write expressions such as these:  $$\int (\theta^2 + \sec^2 \theta) d \theta, \ \int (\cos x + 3^x) dx, \ \int (4x - \csc^2x) dx,$$  do you think it is because angle stated in radian, unlike in degree, can be treated as scalar and be multiplied with each other, since radian actually comes from arc length?  (2) If that is true, do you think that the set of angles expressed in radian, $\mathcal R$, and the set of angles expressed in degree, $\mathcal D$, are probably good examples of ring and group, in that $\mathcal D$ takes only addition as the only operation?  (3) Taking it one more step further down, do you think $\mathcal D$ is also a good example of $\mathbb R$-module?  I am asking these questions not only for my curiosity, but also exploring the possibility of using them in my master thesis, although I am not sure if they have enough depth and breadth. Thank you all for your time and effort.    POST SCRIPT: I think my question is different from those linked to this posting. Whereas the others asked mostly "Why calculus uses radian instead of degree?" but I asked "It is true that radian takes multiplication and degree doesn't?" since I would like to take them as example of group versus ring. Having said that, however, from the multitude of links that I receive here, it appears that my observation is wrong. Calculus uses radian for some other deeper reasons. Thank you all very much for all your time and help. Happy Halloween.

I think this is just something I've grown used to but can't remember any proof.  When differentiating and integrating with trigonometric functions, we require angles to be taken in radians. Why does it work then and only then?


If $p, q$ are primes and $p$ does not divide $n-1$ and $p$ divides $n^q-1$. How to prove that $q|p-1$.  What we can see is that $p|(n^{q-1}-n^{q-2}+\cdots -1)$. Now how do I prove that $p|q-1$

Attempted Proof:  Let $S = \{k: n^k-1 \equiv 0 \pmod{p}, k\in \mathbb{N}\}$. Minimal element $r$ exists by Well-Ordering. we show $r=q$.  We note, $\gcd(p,n)=1$, otherwise $p \mid n^q-1 \implies p \mid 1$.  We have:  $n \not\equiv 1 \pmod{p}\implies n^2 \not\equiv n \pmod{p}$ ; [since $p , n$ are coprime and  $p$ prime ]. Now, for any $0<j< i < r,$  $n^i \equiv n^j \pmod{p} \implies n^j(n^{i-j}-1) \equiv 0 \pmod{p} \implies (n^{i-j}-1) \equiv 0 \pmod{p} $, contradicting the minimality of $r$.   Now, we proceed to show that, all elements of $S$ are integral multiples of $r$. (Claim 1)  We have, $n^{tr} \equiv 1 \pmod{p} \implies n^{tr+l} \equiv n^l \pmod{p} $, for $0\leq l <r$. Now, for any two such $l$, say $c$ and $d$, with $d<c$ ,   $n^{tr+c} \equiv n^{tr+d} \pmod{p} \implies n^{tr+d}(n^{c-d}-1) \equiv 0 \pmod{p}$, which again contradicts our assumption that $r$ is the least element of $S$. Hence, Claim 1 is established. But, it implies that $q$ is composite (an impossibility); hence $r$ must be equal to $q$ .   Finally, by Fermat's Little Theorem, we have $n^{p-1} \equiv 1 \pmod{p}$ [ it holds, since $\gcd (p, n) =1$].   Therefore, $p-1$ must be an integral multiple of $q$, i.e. $q \mid p-1$.   PS: I am aware of the duplicates, but I want my solution checked. Thank you.


A couple of months ago I had published on my blog an article with a title in the form: what is a table (table is not really the word I used-I write the word here as an example).  I had seen through Google Keyword Planner that this search term has very low competition and a decent volume. However, when I search in Google for this term I cannot find my post even in the last page after 450 results. Apart the first couple of Google pages with relevant results, all other pages which outrank my post do not answer the particular question (what is a table) but they have a great density of the word table in their content just because they happen to make or sell tables.  On the other hand, when I put the search term in quotes ("what is a table") I find my post in the 7th position of the first page!  My post's url is in the form www.example.com/eating/what-is-a-table/ and the post is optimized with Yoast SEO plugin (wordpress). The plugin returns that my keyword contains a stop-word which is the word "a", however I have to include "a" as it is a part of the search term which I'm targeting. My site is 15 months old but I rank decently in other search terms. For example in the term [table definition], my relevant post ranks on the 4th page. The posts [what is a table] and [table definition] were published on the same date.  In light of the above explanations and in a few words the question is: why search results differ so much when this search term what is a ...  is asked within quotes or not.

What are the best ways to improve a site's position in the Google search results?


$$\lim_{x \to \infty}\:\: \frac{1+2+3+...x}{x^2} $$ How can I find the limit of above expression. Please tell me which identities and theorems to apply.

Does the following sequence converge or diverge? If it converges, find its limit.  $\frac{1^1}{n^2}+\frac{2^1}{n^2}+........+\frac{n^1}{n^2}$  I tried to get a general formula for this sequence and simply got:  $\frac{n}{n^2}$ or $\frac{1}{n}$  This led me to think that the sequence converges to $0$ since the limit of this function is $0$. But this limit is incorrect. This tells me the general formula I got for the sequence is incorrect. But I am not sure why.  Any help?


I'm building a very simple component in Vue to preview PDF files and images in a modal. I'm using . In the body of the modal I have the following line: <embed :src="fileSrc" type="application/pdf" height="100%" width="100%"> fileSrc is a prop that the component receives. When the modal is launched, the PDF visualizer doesn't show and Google Chrome emits a warning saying:  Flash is blocked on this page   I have allowed flash to be displayed on the page but still doesn't work. If I remove the type="application/pdf" attribute and the fileSrc is a JPEG file, it shows up just fine.  I've also tried with the <object> tag with no luck. What should I check? What am I missing? Edit: Why is this question not a duplicate? Because I wan't to be able to use the <embed> tag to support not only PDF but also images for previewing. The examples in  work without enabling Flash and without warnings, so I should be able to reproduce this behavior.

What is the recommended way to embed PDF in HTML?   iFrame?  Object?  Embed?   What does Adobe say itself about it?  In my case, the PDF is generated on the fly, so it can't be uploaded to a third-party solution prior to flushing it.


For example:  for /F "taken=1,2* delims=;" %%i in(%TABLES%) do( echo select %%j from %%i; | sed -e “s/,/||’,’||/g” -e “s/@/||’@’/g” >> %TABLES_OUT/¥%%i.sql   I want to replace string string instead of sed. Like this  , ➡ ||’,’|| @ ➡ ||’@   What should I do?

I am writing a batch file script using Windows command-line environment and want to change each occurrence of some text in a file (ex. "FOO") with another (ex. "BAR"). What is the simplest way to do that? Any built in functions?


Which is correct — "a two-week all-expense-paid trip" or "a two week all-expense-paid trip"?

Possible Duplicates:                In the sentence "Portland is known to be one of the most bike friendly cities in the US", is a hyphen necessary in "bike friendly"? As far as I know, the hyphen is only required when leaving it out would cause ambiguity. Wikipedia uses the example of "a small appliance factory" vs "a small-appliance factory".   As far as I can tell, the sentence above is pretty clear. A quick google search for "bike friendly city" brings up instances of both hyphenated and non-hyphenated usage. Thoughts?  Please excuse the poor formatting, sent from my iPhone.


How Do I Include References in an ASP.NET web site?  In a typical C# program, when you want to include a name space, it is fairly easy to inculde the reference in the Visual Studio project.  I am trying to rebuild a asp.net C# web site from scratch  -- that is modeled after an already existing asp.net C# web site.  In the preexisting project, the .aspx files have tags such as " components probably do not need any special declaration and the project will run fine immediately after construction.  I also  unserstand what the "tel" tags are for (it is for a plug-in that is part of a third party compoenent that actually adds content to Visual Studio so that I can create a new project of that type).  But the "sue" referrs to a dll that is proprietory to where I work.  I need to include that DLL (and/or pdb file) in a new project.  How do I do this?

Imagine the following solution:   Website ABC.com (not Web Application) BLL (business logic layer in a seperate assembly) DTO (dto objects in their own assembly) DAL (data access layer in it's own assembly as well).   The BLL has a reference to the DAL. The BLL has a reference to the DTO layer. The Website project references the BLL.    When one compiles the website project, the following DLLs will appear in the BIN directory: BLL.dll DTO.dll DAL.dll    When one goes to preview the site, an error occurs about not having the necessary assembly references... Now if one right clicks on the website project, Add Reference, and explicitly add the reference to the missing assemblies, it will work fine.  It seems to me like ASP.NET pulls the referenced assemblies of the referenced assembly being added/referenced in the website.    Why does one need to add explicit references to the references of the references... ? Sorry if I'm not wording this correctly or if it confusing.


I was just trying to solve a problem that had the following item which I needed to split into separate generating functions:  $$\frac{x}{(1-2x)^2(1-5x)}$$  I had assumed I needed to split it into:  $$\frac{A}{1-2x} + \frac{B}{1-2x} + \frac{C}{1-5x}$$  But according to Wolfram Alpha it appears I had to split it into:  $$\frac{A}{1-2x} + \frac{B}{(1-2x)^2} + \frac{C}{1-5x}$$  Can anyone explain the intuition behind this? Is this a general rule that when you have a repeated factor in the denominator, you split it into all powers of that factor?

I'm learning about partial fractions, and I've been told of 3 types or "forms" that they can take  (1) If the denominator of the fraction has linear factors:  $${5 \over {(x - 2)(x + 3)}} \equiv {A \over {x - 2}} + {B \over {x + 3}}$$  (2) If the denominator of the fraction has quadratic factors that don't factorise:  $${{2x + 3} \over {(x - 1)({x^2} + 4)}} \equiv {A \over {x - 1}} + {{Bx + C} \over {{x^2} + 4}}$$  (3) If the denominator has a factor that repeats:  $${{5x + 3} \over {(x - 2){{(x + 3)}^2}}} \equiv {A \over {x - 2}} + {B \over {x + 3}} + {C \over {{{(x + 3)}^2}}}$$    I'd appreciate it if someone could explain to me how these equivalence relationships are derived, essentially how do they take the forms that they do? I sort of understand the first one, but the other two I don't.  Thank you


When is is appropropriate to include or exclude the intercept from a regression model? SPSS provides this option in the GLM menu.  I am assessing group difference (gender) on tasks performed (X) and income earned (Y). In this case, if no task is performed, then no income is earned.     The SPSS guidelines states :  "Include intercept in model. The intercept is usually included in the model. If you can assume that the data pass through the origin, you can exclude the intercept."  My stats knowledge is a bit rusty now but I remember my teacher saying that you should never exclude the intercept!

I am running linear regression models and wondering what the conditions are for removing the intercept term.   In comparing results from two different regressions where one has the intercept and the other does not, I notice that the $R^2$ of the function without the intercept is much higher. Are there certain conditions or assumptions I should be following to make sure the removal of the intercept term is valid?


Is there a way to use different keyboards in different apps? I want to use GBoard for every app except for my Terminal, in which I want to use Hacker's Keyboard. I want to do this because GBoard is a great keyboard, but I can't use arrow keys, ctrl+c, etc.  How could I use different virtual keyboards for different apps without using paid software?  This is different from  because the answer includes paid software.    I am using the OnePlus 5 with OxygenOS 4.5.10 (Stock ROM) (Based on Nougat 7.1.1)  Using this kernel:   Rooted with Magisk   Using the Kali Nethunter terminal:   Kali Nethunter installed with this Magisk module:

I would like to tell my Android that when I'm in a given app it should switch to a given keyboard. My use case is that I want to use Hacker keyboard with Connectbot.


Well, I'm asking for help from other SF fans because I'm trying to recover the title of a novel I read years ago... Obviously I don't remember the title or the author. I remember that the plot was about a spaceship that, for some reason, finds itself in a distortion due to which it begins to increase in volume (I think it's something like that). An image that I remember well is that at a certain point, in the central area of said spaceship, where a corpse had been placed, something milky appears and gets bigger. At the beginning the crew thinks it is a ghost but as time goes by they realize that it is a galaxy.

The Book is about an earthship exploring the frontiers that I read as a kid (80's). All the stories are told by the same character but different encounters and events.    The first story is about the crew exploring the planet in a number of separate ships when one of them is taken over by a telepathic alien. As the ship returns however the surprise is sprung on the alien that the Mother ship is Computer controlled. Another is the ship shrinking and then finding after its shrunk beyond the atom that it comes back in as gigantic compared to the Universe in a closed loop.   Hopefully that's enough to trigger a memory.


import java.util.ArrayList;  class Knapsack {  // A utility function that returns maximum of two integers static int max(int a, int b) { return (a > b)? a : b; }  // Returns the maximum value that can be put in a knapsack of capacity W static int knapSack(int W, int wt[], int val[], int n, ArrayList<Integer> iteration) {      int i, w;     int K[][] = new int[n+1][W+1];      // Build table K[][] in bottom up manner     for (i = 0; i <= n; i++)     {         for (w = 0; w <= W; w++)         {             // add 1 to count up the iterations.             iteration.add(1);             if (i==0 || w==0)                 K[i][w] = 0;             else if (wt[i-1] <= w)                 K[i][w] = max(val[i-1] + K[i-1][w-wt[i-1]],  K[i-1][w]);             else                 K[i][w] = K[i-1][w];         }     }      return K[n][W]; }   // Driver program to test above function public static void main(String args[]) {     // 16 items     int Weights[] = {1, 4, 6, 2, 5, 10, 8, 3, 9, 1, 4, 2, 5, 8, 9, 1};     int Values[] = { 10, 5, 30, 8, 12, 30, 50, 10, 2, 10, 40, 80, 100, 25, 10, 5 };      // Max weight      int  W = 20;      // number of item which is 16     int n = Values.length;      // Count up the iteration      ArrayList<Integer> iteration = new ArrayList<Integer>();      // Will print out the Max value result.      System.out.println(knapSack(W, Weights, Values, n, iteration));     // returns 280      // Should print out the number of iteration.     System.out.println(iteration.size());     // returns 357    }  /*This code is contributed by Rajat Mishra */ }   Hello! This is my first questions to StackOverflow, Hope it is not a duplicated question.   The code above is originally from . I made a slight change to find out how many iterations needed to solve the problem.   Dynamic programming algorithm for Knapsack problem should give a time complexity of O(nW), When n is the number of items and W is the capacity of the knapsack.   But The algorithm returns iterations of 357. Because I thought, since   n = 16 W = 20   Thus, It should give 320 iterations.   Can anybody explain what's wrong with this?    The code is wrong Time complexity doesn't always match to the result.

I'd prefer as little formal definition as possible and simple mathematics.