Sometimes when I look at my suggested edits I see some which have been rejected by  even when accepted by other users. How can this be? I thought  was just a background, automated process. Does it really have veto over suggested edits?

Why does the Community user sometimes approve or reject edits? How does a machine know if my edit is valid? What does it mean if my edit was rejected by Community?     See also:


I will be travelling between Vienna and Prague in December. My plan is to buy local SIM card but as Vienna/Prague are very near to each other, i was wondering if any mobile operators offer combined plans for both cities.  Any ideas on this?

This summer I will go on a road trip from West to East Europe and back. Being able to call and especially access the internet is useful on the road, so it made me wonder whether I could buy a European SIM card or something that would let me access the web or make calls regardless of the country I was in.  I know of the provider Mobile Vikings that offers a . Are there any other alternatives? Data is the main priority because calling or texting within Europe isn't that expensive to begin with, with recent regulations. Also I could use the data to call using VOIP anyway, which is even cheaper.


Is there a terminal command or solution to allow me to visually remove the app icon from the Dock and from the shortcut viewer ( tab + option )?   Ideally, the app should be 100% invisible and running in the background.  i tried ghostviewer and it didnt work. thanks

Is there a way to hide certain apps from cmd+tab?  The problem I'm facing is that I have some apps (like iTunes and of course Finder) always open. But when I'm working and switching between apps that are relevant for me (Chrome, Sublime, Terminal) with cmd+tab I'll always see these 'irrelevant' apps in the menu.  Thanks


How should I define the function size_of so that it will return me 25, size of array A  from pointer p.      #include <stdio.h> #include <string.h>  int main() {     char A[25], B[]="My String";     strcpy(A, B);     size_of(A);     return 0; }  int size_of(char *p) {   }

First off, here is some code:  int main()  {     int days[] = {1,2,3,4,5};     int *ptr = days;     printf("%u\n", sizeof(days));     printf("%u\n", sizeof(ptr));      return 0; }   Is there a way to find out the size of the array that ptr is pointing to (instead of just giving its size, which is four bytes on a 32-bit system)?


I am trying to do an upsert using Database.Upsert() and getting this error: "caused by: System.DmlException: Upsert failed. First exception on row 200; first error: UNABLE_TO_LOCK_ROW, unable to obtain exclusive access to this record or 13 records:" Normally, the code works fine, but on occasion I get the above error. I know in SOQL statements you can use "FOR UPDATE", but I am doing Database.Upsert().  Is there anything that can be done to solve for this error?

Error Message:     Developer script exception from Nicomatic : quotepotential :   quotepotential: execution of AfterUpdate caused by:   System.DmlException: Update failed. First exception on row 0 with id   a0Q90000005PoxtEAC; first error: UNABLE_TO_LOCK_ROW, unable to obtain   exclusive access to this record: [] Trigger.quotepotential: line 14,   column 1      Apex script unhandled trigger exception by user/organization:   00590000001A6jh/00D90000000bovq      quotepotential: execution of AfterUpdate      caused by: System.DmlException: Update failed. First exception on row   0 with id a0Q90000005PoxtEAC; first error: UNABLE_TO_LOCK_ROW, unable   to obtain exclusive access to this record: []      Trigger.quotepotential: line 14, column 1   these mails are getting to my mail..........  trigger quotepotential on Quote_Line_Item__c (after insert,after update) {     Set<Id> quoteIds = new Set<Id>();     List<Quote__c> quotes = new List<Quote__c>();     for (Quote_Line_Item__c record: Trigger.new) {         if (record.Quote1__c != null){             quoteIds.add(record.Quote1__c);         }     }     for(AggregateResult ar:[                 SELECT                      Quote1__c,                      SUM(Max_Batch__c)sumMax                  FROM Quote_Line_Item__c                  WHERE Quote1__c=:quoteIds                  GROUP BY Quote1__c                 ]) {          quotes.add(new Quote__c(              Id=(Id) ar.get('Quote1__c'),              Potential__c = (Decimal) ar.get('sumMax')              ));     }     if (quotes.isempty() == false) {         update quotes;     } }


the is the function I want to set a test for, and it is in the .py file name_function.py def get_formatted_name(first, last):     """generate a neatly formatted full name"""     fullname = f"{first} {last}"     return fullname.title()  The main programe: import unittest from name_function import get_formatted_name as gfn  class NamesTestCase(unittest.TestCase):     """Test For 'name_function.py'."""     def test_first_last_name(self):         """Do names like 'Janis Joplin' work?"""         formatted_name = gfn('janis', 'joplin')         self.assertEqual(formatted_name, 'Janis Joplin')  I don't understand the block below if __name__ == '__main__':     unittest.main()

Given the following code, what does the if __name__ == "__main__": do?  # Threading example import time, thread  def myfunction(string, sleeptime, lock, *args):     while True:         lock.acquire()         time.sleep(sleeptime)         lock.release()         time.sleep(sleeptime)  if __name__ == "__main__":     lock = thread.allocate_lock()     thread.start_new_thread(myfunction, ("Thread #: 1", 2, lock))     thread.start_new_thread(myfunction, ("Thread #: 2", 2, lock))


Both Nvidia and Noveau were working fine before my bios update and now they both crash when I change the brightness. Integrated still works fine with brightness and I've tried several Nvidia drivers with no change. Any help would be greatly appreciated, I am not sure where to start.

I recently installed Ubuntu 11.10 on my Mac Book Pro 7,1. I installed the NVIDIA driver (285). The brightness keys are working (F1 and F2) and I get the box showing the brightness but it does nothing. I can change the brightness in the NVIDIA X Server Settings application. How can I get the brightness working without uninstalling the driver? Thanks in advance.


I have pc and laptop and I am using ubuntu 14.04 beside windows xp sp3 on both devices. I tried to share folders between them .   I installed Samba . Set a user and password . Set folders as shared (on ntfs partitions ) on both devices. Tried to get into Workgroup network but keeping ask password and do not response when I entered the password that I set on samba or user password.   I can get into shared files on windows using Ubuntu only but not vice versa. I tried Ubuntu-Ubuntu from desktop keep asking basswd and from laptop do nothing  Any help please.

I have a desktop (Ubuntu 13.04 & Win 7 Home Premium) and a Laptop (Ubuntu 12.04), both having WiFi adapters. I also have a WiFi router connected to internet which both my computers can access.  I want to share files between my desktop and my laptop using WiFi (similar to Homegroup on Windows 7 but without using Ethernet cables).  How do I set-up that?  I want to share files using both OSs, if anyone have have information about sharing files with any of the OS please answer!


When you start an HTML page you start with a certain set of elements. The user can then obviously add new elements to the page and those changes can immediately be viewed. One problem I have noticed though is that javascript/jquery isn't able to see these newly added elements, it is as though it can only see the elements that were present when the page was loaded (so the elements in the HTML page). Therefore you can't add any events to those new elements.  $('#old_element').on('click', function() {  var frag = $('

')  $('#old_element').append(frag); })  $('.new_element').on('click', function() { $(this).hide(); })   Here you can see an example I made.   I couldn't find any place that had an answer for this, so does anyone here have any?

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.


Given:  $F_0 = 1 , F_1 = 1$, For 2 and so on $F_n = F_{n-1} + F_{n-2}$ (Fibonacci series).  Need to prove by induction:   For each natural $n$ there is a natural number $k$ and numbers:   $a_0, a_1, ..., a_k \in \{0,1\}$  So it exists: $$n = \sum_{i=0}^{k}a_iF_i$$

Can anyone hint me to prove:  $\forall n\in \mathbb{N}: \exists$ Fibonacci numbers $ F_{i_1},\ldots,F_{i_k}$ such that: $$\sum F_{i_k}=n$$    Note: Every Fibonacci number can appear only once. Thanks


This issue has been previously raised e.g.  and  but it remains unanswered, so I would like to raise it again. The REVTeX package automatically merges some footnotes in the author list. For instance, consider the following. \documentclass[superscriptaddress]{revtex4-1}  \begin{document}  \author{Author A} \thanks{Footnote.} \affiliation{University A} \affiliation{University B}  \author{Author B} \thanks{Footnote.} \affiliation{University B}  \maketitle  \end{document}  Here, the repeated footnotes (affiliation B and the \thanks footnote) are merged:  However, adding email addresses messes things up. \documentclass[superscriptaddress]{revtex4-1}  \begin{document}  \author{Author A} \thanks{Footnote.} \email{a@a.edu} \affiliation{University A} \affiliation{University B}  \author{Author B} \thanks{Footnote.} \email{b@b.edu} \affiliation{University B}  \maketitle  \end{document}   I would like to merge the common \thanks footnote, but keep the email footnotes separate. Altogether, this would give 3 footnotes, with each author having two (in addition to affiliation). Is this possible with REVTeX? If not, is there an easy way to patch it to allow for this behavior?  A workaround which sometimes works is to put the \email after \affiliation, but this places the footnote mark in the affiliation and it only works when there is no ambiguity (no affiliation shared between different authors). To clarify why the answer in  is not applicable: the code provided there only works with one affiliation footnote (e.g. \thanks but no \email) and breaks down if one tries to use both, as I have shown above.

REVTeX automatically combines \email and \thanks macros into a single footnote, and uses the same footnote if multiple authors share the exact same set of macros.  Is there any way to force the \email and \thanks macros to have their own footnotes so that two authors can share the \thanks note?  e.g. I would like the author list to look like:     A. Author,a),b) B. Author,b) C. Author   a) Electronic address: a@example.com b) These two authors   contributed equally   The Review of Scientific Instruments  does this, however I cannot work out how to get this result in REVTeX.


What's the simplest way to join one or more arrays (or ArrayLists) in Visual Basic?  I'm using .NET 3.5, if that matters much.

Is there a built in function in .NET 2.0 that will take two arrays and merge them into one array?  The arrays are both of the same type. I'm getting these arrays from a widely used function within my code base and can't modify the function to return the data in a different format.  I'm looking to avoid writing my own function to accomplish this if possible.


I've freed some space on my Windows partition as you in the screen. I've 5 GB of clean unallocated memory that is ready for use. When I try to resize my Ubuntu partition, I've the option to shrink the storage space but not to augment it as you in the second screen. I've browsed through the whole related question but I can't find a clear answer as to why I can't allocate the free space to my Ubuntu partition which is "filesystem Partition 5". I would be really gratefull to anyone who can guide me combine that 5 GB with the memory space initially allocated to Ubuntu. First image:  Second image:

Till today I was using ubuntu 13.04 in my windows7/ubuntu dual boot. Just now I have upgraded to ubuntu 14.04. My software updater showed an updates available message. I proceeded with  Install Now . Soon I got the following window.    Then I tried sudo apt-get clean as recommended. Nothing happened! Not even a window opened. Teach me deleting the temporary packages.   Deleting temporary files may not be highly helpful in case of further updates and installs for I don't have too much space left in my /. I wanna extend my / partition with the help of the unallocated space in my HD. The following is my Gparted window.       I got an answer . But it wasn't useful for me. I had two choices. But the answer wasn't working for both my chioces.  Choice 1: I may use the 4.25 GiB unallocated space to extend my /dev/sda10. To do so, I must need to move my linux-swap partition. But my Resize/Move option is disabled for the linux-swap partition. Choice 1 failed!   Choice 2: I may use the 14.35 GiB unallocated space instead. In this case I must move more than one partition. /dev/sda4  partition is the first on the list. Even that partition has the same problem. Resize/Move option is disabled. Choice 2 failed!  I am out of choices now.  What shall I do? Help me to extend my / with Gparted.


I have Android 4.3 jelly bean on my Nexus 7. How do I get Kitkat?  I have tried exploring the Android website. I have also found some tutorials out there like this one -   but they seem to require taking steps that are quite low-level. I don't think a consumer like me is supposed to delve into such a low-level ...

Android 4.4 (KitKat) was officially announced on October 31, 2013.  (You can review  at the official Android Developer's site or the .)  Of course, not all devices will get this update right away and others won't get it at all. Each manufacturer and carrier often choose to add their custom modifications which tend to delay the official release.  When will each device get Android 4.4, either officially or unofficially, if ever?  See also:


To be more specific, i have a 16 GB USB with Ubuntu on it, and i use it to boot from it, but i want to save all my installations etc. so when i restart the computer or reboot again i wont have to restart my installations again. I also used terminal do install these programs, so will it be possible to sort of change the place where it is installed that way it will be on my C drive and ill only have to boot Ubuntu to run them. so in short I want to use the USB as another hard drive for the laptop. thanks,

If you are hurrying to reply, System → Administration → StartUp Disk Creator -- no, that's not what I'm talking about.   I want to try Ubuntu 11.04's Unity without touching my existing Ubuntu install.  To do this, I need to install the nVidia drivers first (sigh).  To do this, I need changes to persist a reboot.  To do this, I need to really install Ubuntu on a USB key.  How do you do that?    What I tried   I tried to make a USB key from , then boot from it, then choose "Install Ubuntu." The installer refused to install to the installation media itself. I tried, from my installed copy of Ubuntu:  sudo kvm /dev/sdb --cdrom .cache/testdrive/iso/ubuntu_natty-desktop-i386.iso   ...but the installer didn't detect the disk properly.


At the moment, I’m using a second, less restrictive Firefox profile to use SE. In my normal profile, I try to block everything from loading I didn’t really ask for. Sadly that breaks SE, as I can’t log in or show more answers. I think it would be possible to use scripts for all that which are not hosted by Google but by SE itself. Pity SE is following this ill fashion. I don’t think I’m going to be using the less restrictive profile every time I’d like to post on SE. I don’t think anyone will mind, on the other hand, but maybe this gives to think a bit. I bet I’m not the first one writing about this, still, should make it look more important.

I block everything Google, including Google APIs, as I don't like to to have Google tracking all of my usage on the Internet. Is there any way to use Stack Exchange without Google APIs?  I usually am browsing with Windows 7 and Firefox, but of course not Firefox with StackExchange.


In a somewhat similar problem as in  in Texstudio spellchecking does not work when I use \autocite.  Here is a MWE to show what I mean  \documentclass[12pt,a4paper]{memoir} \usepackage[utf8]{inputenc} \usepackage{lipsum} % just for dummy text \usepackage[notes, backend=biber, bookpages=false]{biblatex-chicago} \usepackage{filecontents}  \begin{filecontents*}{\jobname.bib} @book{book1, address = {Anytown}, booktitle = {Example book}, pages = {5}, title = {{Any book you want}}, year = {2000} }  \end{filecontents*}  \addbibresource{\jobname} % if you’re using biblatex \begin{document}  \lipsum[1]\autocite[Transcript of Letter from Mr A to Ms B with some mispelledd texte, p.89]{book1}  \end{document}   For some reason the misspelled text in the \autocite[mispelledd texte]{citekey} does not show up in the spellchecker. I have the biblatex-chicago.cwl ticked in the completion tab of configure TexStudio as per  but it has had no effect. I have english-gb dictionary loaded in Texstudio.  My question is that is there any way to enable spellcheck for \autocite?

I am trying to find a way to enable spell-check in cases such as:   \remark[I don't understend this]{$2+5=7$}   I found something that might look as an answer but it sadly does not work ... In 'configure TexStudio' -> 'editor' I unchecked both 'hide spelling errors in non-text ..' and 'hide grammar in ...'.


The  package transforms source-code hyphens (-, U+002D) into minus signs (−, U+2212) when using the default proportional fonts, though not when using the default monospaced typewriter font.  A minimal working example:  \documentclass{article} \usepackage{listings} \lstset{language=C}  \begin{document}   \lstinline[basicstyle=\rmfamily]{--x} \textrm{-{}-x} \par   \lstinline[basicstyle=\sffamily]{--x} \textsf{-{}-x} \par   \lstinline[basicstyle=\ttfamily]{--x} \texttt{-{}-x} \end{document}   The first two rendered lines clearly show the difference between the long minus signs and the short hyphens:    This is not just an aesthetic problem.  The listing is genuinely no longer correct code.  A minus sign is not a hyphen, and the syntax of C (and most other languages) does not treat them as interchangeable.  --x is valid C code, but −−x is not.  If a non-Unicode-savvy person tries to copy and paste the code from such a listing, she may find that it does not compile but be baffled as to the problem.  How can I prevent listings from turning hyphens into minus signs?

I'm just trying to insert source code into the LaTeX file with listings package. the TeX code goes as follows:  \documentclass{article} \usepackage{listings} \usepackage{color} \usepackage{fontspec} \newfontfamily\Monaco{Monaco} \lstset{    basicstyle=\footnotesize\Monaco }  \begin{document} \lstinputlisting[language=C++]{filename.cpp} \end{document}   However, the - symbol in the code was not displayed in the font Monaco I used, instead, it's using the Math-Type minus. (As shown in the image below)   I searched it on google and found several fixes, e.g. column=texcl, but none of them worked. Thank you for your help in advance.  btw, The environment is TeXLive 2017 on Windows 10


Is there any special incentive for universities to have many athletic students? I am speaking based on my personal observation on North American universities.  I often hear that universities look for students that are "well-rounded", but I do not believe that alone explains the numerous special early offers given to athletic students. This phenomenon, combined with some acknowledged cynicism, led me to this question.

In the USA, college sports are popular, and colleges .  Yet, , and .  Considering that the universities are losing money on it, and it's not their core task, then why do they spend big money on sports?  Who benefits, and how?  Do all  have commercialised sports teams, or are there major exceptions of universities choosing not to take part?


Consider the estimator of the variance given by the formula: $(S')^2 = \frac{1}{n} \sum_{i=1}^{n}(Y_i − µ)^2$      Is this   a biased or unbiased estimator?   I'm not sure if it is possible to prove this without any additional information. Is there something missing?

I was asked today in class why you divide the sum of square error by $n-1$ instead of with $n$, when calculating the standard deviation.  I said I am not going to answer it in class (since I didn't wanna go into unbiased estimators), but later I wondered - is there an intuitive explanation for this?!


I have submitted a manuscript to a reputed journal. After 2 months of peer review process, the response was “moderate revision has been requested” and they told me that the new version is required within 1 month. After making the necessary adjustments, I have resubmitted the revised manuscript back on the 14th of October 2017. On the 21st of October the status changed from “with editor” to “under review”. To date (16th December) the status is “under review”. In fact, I had made some readings about late reviews, I found that reviews are normally due 14 days after the invitation is accepted by the reviewer. Should I worry about manuscript rejection? Thanks in advance for your help

What steps does a manuscript typically go through from submission to publication (or rejection) in a typical journal? How are these steps referred to, in particular by editorial systems, and how long do they each typically take?  Note that this question is about the typical situation and hence not about:   Journals with an atypical workflow, e.g. those that allow for an instantaneous reviewer–author interaction. Exceptional steps or rare occurrences such as withdrawal or .   This is a canonical question on this topic as per . Due to its nature, it is rather broad and not exemplary for a regular question on this site. Please feel free to improve this question.


If the universe is constantly expanding faster than the speed of light, how could Einstein be right?

The observable universe is approximately 13.7 billion years old. But yet it is 80 billion light years across. Isn't this a contradiction?


I know that fermions have a spin of half of and bosons have a spin of 1 but at many places I have seen that their is written that spin for a boson can be 0,1,2.... Is there any physical meaning of spin greater than 1 or is it just a pridiction as to what possible spin magnitude can be.

It is commonly asserted that no consistent, interacting quantum field theory can be constructed with fields that have spin greater than 2 (possibly with some allusion to renormalization). I've also seen (see Bailin and Love, Supersymmetry) that we cannot have helicity greater than 1, absenting gravity. I am yet to see an explanation as to why this is the case; so can anyone help?


I have 2 integer values which represents a cell index in an excel sheet(excel 2010) and I need to create the corresponding excel cell representation(i.e 0,0 represents A1) out of it -  a basic string.  For example: - If the cell index is 0,0 then my code should output A1 (represents the first cell)   If the cell index is 0,1 then it should output B1 If the cell index is 0,27 then it should output AA1 If the cell index is 0,28 then it should output AB1 ..and so on.   I got it correct until A** and not beyond that from the below code..how can I modify the logic to output the correct excel cell representation for other indexes i.e beyond A** and it goes to B** and so on..  Code:   class Program     {         static void Main(string[] args)         {              for (int row  = 0; row < 2; row++)             {                 for (int column = 0; column < 50; column++)                 {                     var header = Headers(column + 1, row).Skip(column).First().ToString();                      Console.WriteLine(header);                 }             }              Console.ReadLine();         }          public static IEnumerable<string> Headers(int column, int row)         {             for (int index = 0; index < column; index++)             {                 if (index >= 26)                 {                     var firstInt = index / 26 - 1;                     var firstAplhabet = ((char)(firstInt + 65)).ToString();                     var secondInt = index - 26;                     var secondAlphabet = ((char)(secondInt + 65)).ToString();                      yield return firstAplhabet + secondAlphabet + (row + 1);                     continue;                 }                  var alphabet = ((char)(index + 65)).ToString();                  yield return alphabet + (row + 1);             }         }     }

How do you convert a numerical number to an Excel column name in C# without using automation getting the value directly from Excel.  Excel 2007 has a possible range of 1 to 16384, which is the number of columns that it supports. The resulting values should be in the form of excel column names, e.g. A, AA, AAA etc.


I am an American and will be moving to the UK next month and I would like to drive around in a week's time to look for houses.   I am sub-consciously oriented to driving on the right side of the road and I was wondering if there are any games or simulators that are effective to re-wire the muscle memory for driving on the left?  I am looking especially for simulators or games because I am not fully sold on the idea of "learn-as-you-make-mistakes" idea yet.

I have driven all my trucks on the right side of the road in the US. I will be traveling to a countries where cars are driven on the left side of the road.   Other than getting driving lessons, what would be an inexpensive way to comfortably acquire this skill?


So, the yellow-green spots in the upper-right corner of this image are my camera's indicator light reflecting off a double-pane glass window.  The bright spots are direct reflections, while the dimmer ones are the result of multiple reflections off the layers of glass.  But why are there four bright spots?  Shouldn't there be only two, one for each air->glass transition?

Last night my daughter was asking why a mirror "always does that" (referring to reflecting a spot of light). To help her figure it out, I grabbed my green laser pointer so she could see the light traveling from the source and reflecting off the mirror.  But as we were playing, I .  Rather than one spot, there were several. When I adjusted the angle to something fairly obtuse    The effect became quite pronounced    And when you looked closely, you could actually see several beams   (Of course, the beams actually looked like beams in real life. The picture gives the beams an elongated hourglass shape because those parts are out of focus.)  I made these observations:   The shallower the angle, the greater the spread of the split beams and resulting dots. The directionality of the reflection is due to the orientation of the mirror, not the laser pointer itself. Indeed, by rotating the mirror 360° the string of dots would make a full rotation as well. I can count at least 8 individual dots on the wall, but I could only see 6 beams with the naked eye. If you look at the split beam picture you can see a vertical line above the most intense dots. I didn't observe any intense spots of light there.   And when I looked closely at the spot where the beam hit the mirror    you can see a double image. This was not due to camera shake, just the light reflecting off the dust on the surface of the glass, and a reflection of that light from the rear surface of the mirror.  It's been a few years since college physics, I remembered doing things like the double split experiment. I also remembered that light seems like it does some strange things when it enters liquid/prisms. I also know that the green laser has a certain wavelength, and you can .  Why does the mirror split the laser beam? How does that explain the effects that I saw? Is there any relation to the double split experiment, or the wavelength/speed of light?


When Installing Ubuntu through virtual box I get an error  This kernel requres an X86-64 CPU, but only detected an I686 CPU. Unable to boot - please use a kernel appropriate for your CPU  How do I fix this?

I was trying to install Ubuntu 12.04 in VirtualBox 4.2.12r84980. I see    this kernel requires an x86-64 CPU, but only detects an i686 CPU, unable to boot   But I am using a 64 bit Windows 8, and trying same .iso for trying Ubuntu. Then what is the problem?


We know Red Skull is in Captain America: The First Avenger, but why is he in Vormir in the first place? How did he get there?  Apart from Marvel trying to close Phase: One, what was the point of portraying this character in this movie?

At the end of Captain America - The First Avenger, when Red Skull and Captain America are fighting on a plane, Red Skull holds the Tesseract in his hands. And soon a portal opens to another space dimension and the Red Skull disintegrates due to the power of the Tesseract.     Did the Red Skull actually die or was he sucked to another space dimension? Because the Tesseract is later revealed to be a Space Infinity Stone


I have a problem with my JQuery, I don't understand why the remove button don't work, could you help me please ? =) So here is my code :    $('.removeBook').on('click', function() {   $('div').remove(); });  $('#createBook').click(function() {   $('#list').append('
Hello' + '<button type="button" name="removeBook" class="removeBook">Remove</button>' + '
'); });  <button type="button" name="createBook" id="createBook">Create</button>

     Thanks in advance if you can help me !

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.


I recall a short lived TV show that I think was broadcast on the British TV channel ITV in the late 90s or early 2000s and it was about time travel. It was set in Britain in relatively modern times. The scene that really sticks in my head is when the protagonist goes to use their time travelling machine they go in to a room where the machine is and they close all the windows. The windows have latches on them and by closing the window it creates a circuit. By closing all the latches the circuit is complete and the machine is able to be activated. I don't know if it's much to go on, but it's been really bugging me for ages.

A British television series from the mid/late 90s, where the protagonist is a detective (?) somehow able travel back in time a few days (perhaps a week?) to solve crimes. I think other characters were unaware of his time travels...  I remember one episode where, during his investigation in the past, he saw a colleague and slipped him a piece of paper with some lottery numbers to play. When he arrived back, the rest of the team were celebrating his win with "bubbly", it then transpired it wasn't actually "real" champagne, confused we find out that:      his colleague had put down the numbers upside-down, somehow meaning he'd got four numbers (several hundred pounds) rather than all of them (several million).   The premise sounds a lot like , though I think this programme was aired prior to that...  Any ideas?


Why reputation of author is not showing on question page, but same is showing in tag page.    Reputation of author is shown in tag page     Reputation of author is not shown in question page

I cannot see reputation of any questioner or answerer on their user cards, but editors' rep & badges are still shown. Questions tab with any filter(new, active) is unaffected. Mobile sites are unaffected. It appears to be a network-wide issue.     New contributor banner expands.


Wolverine was sent back in time and he changed the timeline. But if he changed the events of X-Men: First Class, Apocalypse, etc. then how did he get paralyzed and bald?

Much like Superman III and IV were kind of just...ignored... was it the same with the 3rd and 4th X-Men movies when X-Men: First Class came out?  It seems that most of the inconsistancies with the First Class story come from the last two movies' story lines, so I was just curious.


How do I add and display a custom image field to a category?   I know I need to use the hook 'category_add_form_fields' however I am not quite sure how... I am relatively new to wordpress so any help is greatly appreciated!

I have a custom taxonomy and I want to add a custom field inside  , OK that's seems to be  easy but  the hardest part is when  I want to add a file input type the enctype="multipart/form-data" I already add it to the form .


I'm working with Typescript 2.4 and being stuck with a simple modulo operation :  I wrote a simple unit test of modulo operator to explain my problematic  fit('TypeScript should be able to do a simple mathematic modulo : ', () => {   expect(318.08 % 60).toBe(18.08); });   And as you can guess... this test fail (Expected 18.079999999999984 to be 18.08.).  What did i miss ?  As you wan see google is better as this game :D :

Consider the following code:   0.1 + 0.2 == 0.3  ->  false   0.1 + 0.2         ->  0.30000000000000004   Why do these inaccuracies happen?


When I run this code:  li=["It","is","funny","how","I","fiddled","with","this"] for i in range(0,len(li)):     word=li[i]     for j in range(0,len(word)-1):         if word[j] == word[j+1]:             li.pop(i)             break print(li)   My desired output is:  ['It','is','how','I','with','this']   However, I get the following error message:  Traceback (most recent call last): File "fiddle.py", line 3, in <module> word=li[i] IndexError: list index out of range   Please point out the mistake in my code.

Is there a built-in that removes duplicates from list in Python, whilst preserving order? I know that I can use a set to remove duplicates, but that destroys the original order. I also know that I can roll my own like this:  def uniq(input):   output = []   for x in input:     if x not in output:       output.append(x)   return output   (Thanks to  for that .)  But I'd like to avail myself of a built-in or a more Pythonic idiom if possible.  Related question:


$y_i=\beta_0+\beta_1x_i+\varepsilon $ is a simple linear model.   We know $R^2=1-\frac{SSE/(n-k-1)}{SST/(n-1)} $ where   $SSE=Y'(I-H)Y=\sum(y_i-\hat{y})^2$   and $SST=Y'(I-P_1)Y=\sum(y_i-\bar{y})^2$   (for $H=X(X'X)^{-1}X'$ and $P_1=\frac{1}{n}\mathbf{11'}$ and $\mathbf{1}=(1,\cdots,1)_{1\times n}'$, $Y=(y_1,y_2,\cdots,y_n)'$,$X=\begin{bmatrix} 1 & x_{11}\\   1& x_{21}\\   \vdots&\vdots \\   1&x_{n1 }  \end{bmatrix}$)   Define $r=\frac{\sum (y_i-\bar{y})(x_i-\bar{x})}{\sqrt{\sum (y_i-\bar{y})^2\sum (x_i-\bar{x} )^2}}$.  Show $R^2=r^2$  Thanks in advance.

It is often stated that the square of the sample correlation $r^2$ is equivalent to the $R^2$ coefficient of determination for simple linear regression. I have been unable to demonstrate this myself and would appreciate a full proof of this fact.


I recently graduated with the highest GPA in my undergraduate class of 350 students. My current CV reads -  GPA: 3.x/4 (Ranked 1st out of Undergraduate Class of 350 students)  However, this feels slightly forced and awkward. Is there any better way to write this?  Thanks!

I have a question about how to write my ranking in a class in my CV. I mean, after graduation from the university for my BSc degree, my ranking due to overall GPA among the class of 30 students was 2. The class and the students in which we started our BSc degree education and graduated after 8 or 9 semesters. I want to high light this ranking in my CV in the section of honors and awards. How should I mention this?


Let's say, I write the file testFunc.py, containing  def helloWorld():     print['hello world']   When I run inside the python interpreter (v. 3.5.2)  >>> import testFunc >>> testFunc.helloWorld()   as expected I get the error message  ... error ... line 2, in helloWorld print['hello world']   If I correct the code to  def helloWorld():     print('hello world')   and rerun only the command without closing python in the meanwhile, I get the following error message:  >>> testFunc.helloWorld()  ... error ... line 2, in helloWorld print('hello world')   So I get an error message, even though the code appearing inside the error message would be correct. Apparently Python stored the binary of the function somewhere and didn't recompile it. On the other hand, Python reads out the new source file, which doesn't contain the error anymore.  So why does Python do this? I find this behavior highly misleading. Why does Python not compare the time stamps of the source code and the temporary binary and recompile the source if it has been edited since? Is it because another instance of Python may be currently executing the temporary binary?

I have a long-running Python server and would like to be able to upgrade a service without restarting the server. What's the best way do do this?  if foo.py has changed:     unimport foo  <-- How do I do this?     import foo     myfoo = foo.Foo()


Question: Check whether the polynomial $x^4 - 20 x^2 + 16$ is irreducible over the rationals. Eisenstein's criterion cannot be applied here and I couldn't come up with any other method to check whether this is irreducible or not. Any help in getting this done is much appreciated.

The easy part is algebraic manipulation: $$x - \left( {\sqrt 5  + \sqrt 6 } \right) = 0 \Rightarrow {x^2} = 5 + 6 + 2\sqrt {30}  \Rightarrow {x^2} - 11 = 2\sqrt {30}  \Rightarrow {x^4} - 22{x^2} + 1 = 0$$ Solutions to this equation are ${x_{1,2,3,4}} =  \pm \sqrt 5  \pm \sqrt 6 $ and these are all candidates for the conjugates. However, not all of them are necessarily conjugates of ${\sqrt 5  + \sqrt 6 }$. The hard part is proving that $p\left( x \right) = {x^4} - 22{x^2} + 1$ is the minimal polynomial of ${\sqrt 5  + \sqrt 6 }$ over $\mathbb{Q}$. Eisenstein criterion doesn't give irreducibility when taking $p\left( {x + a} \right)$. Even though $p$ has no rational zeroes, that still doesn't mean that it is irreducible over $\mathbb{Q}$. One method which I can think of would be to calculate each of 7 divisors of $p$ and show that they are not in $\mathbb{Q}\left[ X \right]$. However, that would be impractical in the next problem which has a polynomial of degree 31. How to see that all the candidates are indeed the conjugates of ${\sqrt 5  + \sqrt 6 }$ ?


Suppose N points ((x1,y1),(x2,y2),...(xN,yN)) are given from a curve y=sin(ax+b) where a,b values are unknown. Before giving these N points to you, y coordinate of one point is randomly tampered so that it does not lie on the curve. Write a program to determine which point among N points is NOT on the sinusoidal curve, whose a, b values are unknown

Suppose $N$ points ($(x_1,y_1), (x_2,y_2), ... (x_N,y_N)$) are given from a curve $y=\sin(ax+b)$ where $a, b$ values are unknown. Before giving these $N$ points to you, $y$ coordinate of one point is randomly tampered so that it does not lie on the curve.  Write a program to determine which point among $N$ points is NOT on the sinusoidal curve, whose $a$, $b$ values are unknown.  Any logic on how to approach this question, would be highly appreciate would be very thankful!


I was reading about (simple) linear regression through origin and I have the following questions:   What are the standard assumptions of such a regression model? I am asking this of the true model not the fitted model. In specific if you were to write down before you even fit the model what are assumptions of the error term, assumptions for the distribution of the parameters for inference and so on.  How can you derive the MLE (NOT LSE) of the standard (Simple) regression model through the origin. And by derive I do not mean saying that MLE=LSE in this case and just minimizing the least Squares. I would be quite confused on whether to even start with normal distribution as I am still uncertain of the assumptions of the model through the origin.

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?


I want to create a function that creates an array with every permutation of the sum of positive integers that create a given integer (N).  The example N = 3 would create an array of:  1 + 1 + 1 2 + 1  As I am not a mathematician I do not know the correct terminology so even answers about that would be helpful.

Is there a way to get all possible partitions of an integer? Possibly specifying max and/or min summand. I'm interested in partitions themselves, not just partition count.


I am told there are four fundamental forces, and each of these forces has a boson that acts as its carrier.  Reading this  I find that the Higgs Field is not a force field      The Higgs field is not considered a force. It cannot accelerate particles, it doesn't transfer energy. However, it interacts universally with all particles (except the massless ones), providing their masses.   So I can get this argument, but then the article goes on to claim      The Higgs particle is considered to be a carrier of a force. It is a boson, like the other force-transferring particles: photons, gluons, electroweak bosons. One may call the force mediated by the Higgs boson to be universal as the Higgs boson interacts with all kinds of massive particles, no matter whether they are quarks, leptons, or even massive bosons (the electroweak bosons). Only photons and gluons do not interact with the Higgs boson. Neutrinos, the lightest particles with almost zero mass, barely interact with a Higgs boson. Top quarks, which have about the mass of a Gold atom, have the strongest interaction with a Higgs boson.   So ...   Is the Higgs Field a Force Field? Is the Higgs Boson a carrier of force? Does this mean there are actually 5 fundamental forces? Why is that elephant over there orange?

When I first learned about the four fundamental forces of nature, I assumed that they were just the only four kind of interactions there were. But after learning a little field theory, there are many other kinds of couplings, even in the standard model. So why isn't the Yukawa Higgs coupling considered a fifth fundamental force? To be a fundamental force, does there need to be a gauge boson mediating it?


Consider following system : \begin{cases} x  \equiv 2 \, \text{mod} \,  9   \\ x \equiv 3 \, \text{mod} \, 5 \\ x \equiv 8 \ \text{mod} \, 21 \end{cases} I can't apply the Chinese remainder theorem because the $\text{gcd}(21,9) \neq 1.$ So I want to factorize $21$ and $9$ in prime factors and make new equations. A theorem in my books says if the $\text{gcd}(n,m) = 1$ then $ x \equiv x' \, \text{mod}\ nm  \iff \begin{cases} x  \equiv x' \, \text{mod} \,  n   \\ x \equiv x' \, \text{mod} \, m \\ \end{cases} $. But how do I apply this with the first equation. Because $9=3*3$ and the $\text{gcd}(3,3) \neq 1$. I heard some solution who said that $x \equiv 2\,\text{mod}\, 9$ is the same as  $x \equiv 2\,\text{mod}\, 3$ but I don't understand why they are the same.  Thanks in advance!

$x=1 \pmod 8$  $x=5 \pmod{12}$  8 and 12 are not coprime, I could break it to:  $x=1 \pmod 2$  $x=1 \pmod 4$  and   $x=5 \pmod 3$  $x=5 \pmod 4$  But what are the next steps to solve it? By the way, $x$ should be $17$ not sure how to get that number ...  Thanks in advance.


Trying to create a generic lerp function in C#. My function currently looks like the one below.  public T Lerp<T>(T lhs, T rhs, float t) {     return (1.0f - t) * lhs + t * rhs; }   The question referenced as a duplicate constrains they type to built in types. I don't want to return a constraint I want to return an object of type T(Generic Object?) in C#.

Can anyone tell me if there is a way with generics to limit a generic type argument T to only:   Int16 Int32 Int64 UInt16 UInt32 UInt64   I'm aware of the where keyword, but can't find an interface for only these types,  Something like:  static bool IntegerFunction<T>(T value) where T : INumeric


I'm looking for something like presence of a file or its content that could indicate the headphone's presence. I am working on if statement on conky with condition being presence/absence of headphone/earphone.

I am trying to detect a signal when a headphone is connected or disconnected from the system.  What is the best way to do this?  If there is a special board with drivers, that will be my preferred way.


I know this is really basic, but I am new to javascript and can't find an answer anywhere.  How can I check if a string is empty?

I saw , but I didn't see a JavaScript specific example. Is there a simple string.Empty available in JavaScript, or is it just a case of checking for ""?


I am trying to perform a landscaping job for someone. However, they are telling me that the ex-owner of the house he is trying to buy does not accept credit cards. He is asking me to pay for the closing fee by sending me his credit card information and sending the ex-owner a certain amount to pay for it while giving me the downpayment for the landscaping work that is needed to be done. Should I be cautious of this?

I have a small landscaping business and I advertised through Facebook.   Some guy reached out to me via text message, asking me to do a job for him.  He asked for a quote  for installing sod in his front yard and I replied with $3,175. He agreed  to  that price.  He then asked me to assist him with with the ex-owner of the house. I asked him, what needs to be done? He said that he owes the ex-owner $10,000  and that the ex-owner  has no way of receiving it.  For he only has a credit card to pay with he has to do it as a transaction he will will send me $12,100. Once the money clears I have to Zelle or PayPal the ex-owner   the $10,000 and keep $2,000 as down payment for the job and $100 for a tip.    I thought that this was some kind  of joke so I agreed.  He asked if I could manually process his card.  I said no but I can invoice you.  So I did and to my surprise, he actually paid. I think that I’m being scammed.  What should  I do?


I understand in C , the operator ^is used for bit-wise EX-OR. In one of the C++ code I saw the following lines where this operator is used:   using namespace System::Threading;  public ref class Expert : public System::Windows::Forms::Form {     int i ;         float a ;   public:     int count;     Thread^ th;       }   What is the meaning of ^ here ?

I just came across this code and a few Google searches turn up no explanation of this mysterious (to me) syntax.  Hashtable^ tempHash = gcnew Hashtable(iterators_);  IDictionaryEnumerator^ enumerator = tempHash->GetEnumerator();   What the heck does the caret mean? (The gcnew is also new to me, and I asked about that .)


The "switch case" witch I have write for sin,cos,tan,cot doesn't work when I enter them in operator and it goes to entering second number. Where is my fault? Here is my code:  import java.util.Scanner;  public class MainClass {      public static void main(String args[]){         Scanner NumInput = new Scanner(System.in);         double firstNum = 0;         double secondNum = 0;         double result = 0;         System.out.println("Enter first number: ");         firstNum = NumInput.nextDouble() ;         System.out.println("Enter operator: ");         String amalgar = NumInput.next();             if (amalgar == "sin" || amalgar == "cos" || amalgar == "tan" || amalgar == "cot"){             switch(amalgar){         case "sin":             result = Math.toRadians(Math.sin(firstNum));             break;         case "cos":             result = Math.toRadians(Math.cos(firstNum));             break;         case "tan":             result = Math.toRadians(Math.tan(firstNum));             break;         case "cot":             result = (Math.toRadians(Math.cos(firstNum))/Math.toRadians(Math.sin(firstNum)));             break;          default :              break;                }             System.out.println(Math.toRadians(result));             }             else                  System.out.println("Enter second number: ");                 secondNum = NumInput.nextDouble();               switch (amalgar){         case "+":             result = firstNum + secondNum;             break;         case "-":             result = firstNum - secondNum;             break;         case "*":             result = firstNum * secondNum;             break;         case "/":             result = firstNum / secondNum;             break;          default:             System.out.println("nemifahmam chi neveeshti");         }              System.out.println(result);      } }

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?


I have the following code:  try {     using (var myHttpWebResponse = (HttpWebResponse) httPrequestCreated.GetResponse())     {         var streamResponse = myHttpWebResponse.GetResponseStream();          if (streamResponse != null)         {             var streamRead = new StreamReader(streamResponse);             var readBuff = new Char[256];             var count = streamRead.Read(readBuff, 0, 256);                       while (count > 0)             {                 var outputData = new String(readBuff, 0, count);                 finalResopnse += outputData;                 count = streamRead.Read(readBuff, 0, 256);             }             streamRead.Close();             streamResponse.Close();             myHttpWebResponse.Close();          }     } } catch (WebException ex) {     MessageBox.Show("something went wrong"); }   The error code is 404 Not Found, but instead of a MessageBox I get the following error:    Why is the exception never caught?

The following bit of code catches the EOS Exception  using (var reader = new BinaryReader(httpRequestBodyStream)) {      try {         while (true) {             bodyByteList.Add(reader.ReadByte());         }     } catch (EndOfStreamException) { } }   So why do I still receive first-chance exceptions in my console?      A first chance exception of type 'System.IO.EndOfStreamException' occurred in mscorlib.dll   Is there a way to hide these first chance exception messages?


I have a huge shapefile (roadnetwork of Europe) and a raster file (Europe, 100x100m resolution). I want to calculate the length of the roadnetwork for each raster cell, resulting in a new raster layer. The problem is that the number of raster cells is huge and the roadnetwork is very large. My current approach in R is to build 60x60 sub-raster (using the SpaDES-package, convert each sub-raster to polygons (using stars and sf) and then intersect the polygons with the road network. The problem is that this takes very long. Parallelizing the prozess does not work because of memory limitations (st_intersects/st_intersections cause doParallel to make copies of the whole road network for each thread). Is there a more efficient way to perform the task? Is there some software with which this taks can be done efficiently? Thanks!

I have a line shapefile representing a road network. I wish to rasterize this data, with the resulting values in the raster showing the total length of the lines that fall within the raster cell.  The data is in the British National Grid projection so the units will be meters.   Ideally I would like to perform this operation using R, and i'm guessing that the rasterize function from the raster package would play a part in achieving this, I just can't work out what the function applied should be.


I have had my N7 for about 5 or 6 months now, and I am considering rooting it. I would like to know the best one click rooting methods to use. I've heard of kingoroot, but I don't know if it roots 5.1.1 yet. Thank you

I am wanting to gain root privileges on my Google Nexus 7 tablet, running Android 4.1-4.2.1. How can I do this?


Here    someone stated: "If $p$ a prime number $\mathbb{Z}^{\times}_p$ is always isomorphic to $(\mathbb{Z}_{p-1},+)$" What is this Theorem called? Where can i find it? How to proove it?  Thank you in advance.

I'm looking for a proof of this that does not rely on the Chinese remainder theorem, since the exercise is from a book that has not reached such a point (Aluffi, Algebra).  Show that for $p$ prime, the multiplicative group $G=(\mathbb{Z}/p\mathbb{Z})^*$ is cyclic. You may use that for $p$ prime, the equation $x^d=1$ has at most $d$ solutions in $\mathbb{Z}/p\mathbb{Z}$. (hint: for $g\in G$ of maximal order, $\forall h\in G, |h|\;|\;|g|$, and in particular, $h^{|g|}=1$.)  My only idea for now is constructing an element $a\in G$ such that $|a|=|G|$, using the fact that a group of order $n$ is cyclic $\iff\exists$ an element of order $n$.


I am running into this issue, when i use Object.assign() previous value getting overridden.     var blueprint = {  name: {    first: "Default first name",     last: "Default last name"   } };  var person1 = Object.assign( {}, blueprint );  console.log( blueprint.name.first ); // Gives me "Default first name"  person1.name.first = "John";  console.log( blueprint.name.first ); // Gives me "John" console.log( blueprint.name.last ); // Gives me "Default last name"     Question is how can i override person1.name.first while keep my blueprint safe?

What is the most efficient way to clone a JavaScript object? I've seen obj = eval(uneval(o)); being used, but . I've done things like obj = JSON.parse(JSON.stringify(o)); but question the efficiency.  I've also seen recursive copying functions with various flaws.  I'm surprised no canonical solution exists.


Basically, I'm trying to replace a part of url in the middle ('#') with another one, and remove first part of url. Script replaces '#' with no problem but rfuses to remove the first part of url. Am i doing something wrong, or is there another solution for that?  html of it  Download pdf set   on condition changes to   Download pdf set   jquery  $(".imgdownload").each(function(){     this.href = this.href.replace('#', 'http://#.com/s/files/1/0183/2687/files/pass');    this.href = this.href.replace('http://www.#.com/pages/botanical', ''); });    It's supposed to happen on condition. Judging that the rest of the script works fine on the condition- looks like the problem is somewhere here

How can you change the href for a hyperlink using jQuery?


When I save the table after I set up the classifcation and then ArcGIS save it as a INFO file and then you have two columns that you want to merge into one. Is there a better way to do that ? What I want to get the columns from FROM and TO merge into One column. These are the feet Elevation numbers.  Here is the screenshot

I need to combine two fields in an attribute table.  I want to do this using the field calculator.  What is the proper script to write to combine a field called "name" and "type", so that it produces one field with "name type"?  I'm using ArcGIS Desktop 10.0.


I came across the formula for the $n$th Fibonacci number:  $$\frac{\Phi^n-(-\Phi)^n}{\sqrt5} = x,$$   where $x$ is the $n$th Fibonacci number.  This formula works one way around, but I cannot seem to get it to flip around.  How would I go about isolating $n$?

I'm already aware of the Binet formula $\displaystyle F_n = \frac{\varphi^n + \frac{1}{\varphi^n}}{\sqrt{5}}$. I'm attempting to find the inverse of that formula so I can find the position in the sequence of Fibonacci numbers. In fact, at first glance it's relatively easy:  $$ F_n\sqrt{5} = \varphi^n + \frac{1}{\varphi^n}\\ \varphi^nF_n\sqrt{5} = \varphi^{2n} + 1\\ \varphi^{2n} - \varphi^nF_n\sqrt{5}+ 1 = 0\\ \varphi^n = \frac{F_n\sqrt{5}+ \sqrt{5F_n^2 - 4}}{2}\\ n = \log_\varphi\left(\frac{F_n\sqrt{5}+ \sqrt{5F_n^2 - 4}}{2}\right) $$  But this isn't quite correct. The problem is that we must subtract or add 4 depending on whether the Fibonacci number has odd or even position in the sequence (or rather, whether $5F_n^2 - 4$ is a perfect square; admittedly, we could just go by this indicator, but I want to avoid that if at all possible). So the formula is actually:  $$ n = \log_\varphi\left(\frac{F_n\sqrt{5}+ \sqrt{5F_n^2 + 4(-1)^n}}{2}\right) $$  But that doesn't work for me, because n appears in multiple places in the formula, and you'd need to know if it's odd or even to be able to derive it. So if you do the work, you'll see that I'm trying to isolate n in the expression:  $$ \varphi^{2n} - \varphi^nF_n\sqrt{5} = (-1)^n $$  Or alternatively, find an operation that when applied to the numbers 3, 8, 21, 55, 144, etc. gives an even number, and when applied to the numbers 2, 5, 13, 34, 89 gives an odd number.  As a side note, I find it highly unnerving that the almighty quadratic formula fails in this particular case.  Update: I am only interested in solving either of the two problems posed above, not in other ways to find Fibonacci numbers' positions in the sequence.


The Dirichlet function is defined as the indicator function of rational numbers. I have also seen this function described by: $$f(x)=\lim_{k\to\infty}\lim_{j\to\infty}\cos^{2j}k!\pi x$$ How does this limit act as the indicator, and how does it yield an answer if cosine is limited to Infinity?

I stumbled upon this "relation" (is the name correct?):  $$ \lim_{m \to \infty} \lim_{n \to \infty} \cos^{2n}(m! \pi x) = \begin{cases} 1,&x\text{ is rational}\\ 0,&x\text{ is irrational}\end{cases} $$  How is it called and why is it so? I'm really not asking for a proof since I fear it would be too complicated for me to understand, but rather for an "intuition".


I am using Ubuntu 13.10, and looking forward for the launch of Ubuntu 14.04 LTS. Please suggest me how should I upgrade to 14.04 LTS?

What are the different ways I can use to upgrade Ubuntu from one release to another?


I've just started learning Java, when trying to compile the below source code using "Javac" I am getting the following error:  "C:\Java>javac 99Bottles.java  99Bottles.java:1: error:  expected  public class 99Bottles { //open Class "99Bottles"  Can't seem to figure out if this is a syntax error or if i'm missing something? Any advice would be greatly appreciated, thanks    public class 99Bottles { //open Class "99Bottles"     public static void main (String[] args) { //Open main method         int Beernum = 99; //delcate intergar called "Beernum" with value of 99         String word = "bottles"; //delcare the string "word" with a value of "bottles"          System.out.println(Beernum + " " + word + "of beer on the walL");  //prints         System.out.println(Beernum + " " + word + "of beer"); //prints         System.out.println("you take one down"); //prints         System.out.println("you pass it around"); //prints          Beernum = Beernum - 1; //subtract 1 from the value of "Beernum"          if (Beernum > 0) { //Check if Beernum is greater than 0                 System.out.println(Beernum + " " + "of beer on the wall"); //prints         } else { //if the if statement is not true run this                 System.out.println("no more bottles of beer on the wall"); //prints             }              } }

What characters are valid in a Java class name? What other rules govern Java class names (for instance, Java class names cannot begin with a number)?


I am searching advantage of using Do While, most of blogs and tutorials say its depends on requirement, without that is there any advantage we get from Do While ?  <?php $i = 0; do {      echo $i; } while ($i > 0); ?>

When I was taking CS in college (mid 80's), one of the ideas that was constantly repeated was to always write loops which test at the top (while...) rather than at the bottom (do ... while) of the loop. These notions were often backed up with references to studies which showed that loops which tested at the top were statistically much more likely to be correct than their bottom-testing counterparts.  As a result, I almost always write loops which test at the top. I don't do it if it introduces extra complexity in the code, but that case seems rare. I notice that some programmers tend to almost exclusively write loops that test at the bottom. When I see constructs like:  if (condition) {     do     {        ...     } while (same condition); }   or the inverse (if inside the while), it makes me wonder if they actually wrote it that way or if they added the if statement when they realized the loop didn't handle the null case.  I've done some googling, but haven't been able to find any literature on this subject. How do you guys (and gals) write your loops?


Would anyone know the most efficient way to look for duplicates in a String ArrayList and print out the duplicates?  For example I have an ArrayList containing the following:  ArrayList<String> carLIST = new ArrayList<String>(); carLIST = {"Car1", "Car2", "Car3", "Car1", "Car2", "Car2"};   Basically anything in the list more than once I'm looking to find the duplicates (which I think I've done below) and also return a System.out.println(); to show the following:  Car1   :   count=2  Car2   :   count=3  Map<String,Integer> repeatationMap = new HashMap<String,Integer>(); for(String str : carLIST) {     if (repeatationMap.containsKey(str) {         repeatationMap.put(str,repeatationMap.get(str) +1);     }     else {          epeatationMap.put(str, 1);     }  //  if (repeatationMap.get(str) > 1) { //       System.out.println(repeatationMap.entrySet()); //  } }   The code commented out is what I thought it would be to print out the duplicates but I'm seriously wrong! Have no idea how to print out the duplicate cars in the list and show its count.

How could I go about detecting (returning true/false) whether an ArrayList contains more than one of the same element in Java?  Many thanks, Terry  Edit Forgot to mention that I am not looking to compare "Blocks" with each other but their integer values. Each "block" has an int and this is what makes them different. I find the int of a particular Block by calling a method named "getNum" (e.g. table1[0][2].getNum();


Let A and B be two random variables both independent from another random variable C. If A is independent from B, is A*B also independent from C? And if A and B are no independent from each other?

Is the claim that functions of independent random variables are themselves independent, true?   I have seen that result often used implicitly in some proofs, for example in the proof of independence between the sample mean and the sample variance of a normal distribution, but I have not been able to find justification for it. It seems that some authors take it as given but I am not certain that this is always the case.


I want to count Words with several Threads and every thread has a "wordCount" variable. Now how can i wait till every thread is finished? At the end i should count every variable of each thread together and print it out?  How i create my Threads:  for (int i = 1; i <= THREADS_TO_USE; i++) {     long bytesToRead = splitManager();     new Thread(new CountWordsThread(file, bytesToRead, bytesCounted)).start(); }

I'm making a Java application with an application-logic-thread and a database-access-thread. Both of them persist for the entire lifetime of the application and both need to be running at the same time (one talks to the server, one talks to the user; when the app is fully started, I need both of them to work).  However, on startup, I need to make sure that initially the app thread waits until the db thread is ready (currently determined by polling a custom method dbthread.isReady()). I wouldn't mind if app thread blocks until the db thread was ready.  Thread.join() doesn't look like a solution - the db thread only exits at app shutdown.  while (!dbthread.isReady()) {} kind of works, but the empty loop consumes a lot of processor cycles.  Any other ideas? Thanks.


When installing Ubuntu on my VB I am not able to choose 64-bit because the option is not showing up and yet my laptop runs on a 64-bit CPU. The system is not booting and it keeps on telling me      This kernel requires an x86-64 CPU, but only detected an i686 CPU

I was trying to install Ubuntu 12.04 in VirtualBox 4.2.12r84980. I see    this kernel requires an x86-64 CPU, but only detects an i686 CPU, unable to boot   But I am using a 64 bit Windows 8, and trying same .iso for trying Ubuntu. Then what is the problem?


How can I change the language of just WordPress dashboard, so that the language of site still did not change? a lot of plugins and themes dashboard  becomes mess when I change it to my language, because it's RTL but plugins and themes are just LTR. I don't speak English very well, so sorry for my language.

I have installed a wordpress theme, i can see the .mo and .po /public_html/wp-content/themes/themename/lang, the language I want to use is available.  Could you please advise on how to use a specific language? I don't want to change the admin language just the theme language.


Could I replace "The loved ones are happy." with " The loved are happy." Is it possible to replace?  I learned that 'the' plus 'adjective' means 'prural normal noun'. I think that Past participal 'loved' is a adjective. Is it right?

An adjective appears to be used as a noun when denoting an animate plural and preceded by the definite article:     'The successful are those who strive.'      'The foolish are those who procrastinate.'   Is this always the case?


I was trying to use Mapbox in an LWC component, by importing its library using loadScript, but I am only getting an undefined error in the promise. I created a ZIP bundle with the CSS and JS files (mapbox.css and mapbox.js), and also a test JS file to check there is no problem with the ZIP itself (example.js with a console.log message). I have uploaded it using the Metadata API, and set it as an application/zip, here is the XML file contents: <?xml version="1.0" encoding="UTF-8"?> <StaticResource xmlns="http://soap.sforce.com/2006/04/metadata">     <cacheControl>Private</cacheControl>     <contentType>application/zip</contentType> </StaticResource>  This is the example code I am trying to run: import { api, LightningElement } from 'lwc'; import { loadScript, loadStyle } from 'lightning/platformResourceLoader'; import MAPBOX from '@salesforce/resourceUrl/mapbox';  export default class InquiryMap extends LightningElement {     @api recordId;     mapboxInitialized = false;      renderedCallback() {         this.bootMapbox();     };      bootMapbox() {         if (this.mapboxInitialized) {             return;         }          this.mapboxInitialized = true;                  loadStyle(this, MAPBOX + '/mapbox.css')         .then(() => {             console.log('Mapbox CSS is ready! =)');         })         .catch((err) => {             console.log('Error (CSS)', err);         });          loadScript(this, MAPBOX + '/example.js')         .then(() => {             console.log('Mapbox Example JS is ready! =)');         })         .catch((err) => {             console.log('Error (Example)', err);         });          loadScript(this, MAPBOX + '/mapbox.js')         .then(() => {             console.log('Mapbox JS is ready! =)');         })         .catch((err) => {             console.log('Error (JS)', err);         });     }; }  But this is the output in the console: I am a example JS file Mapbox Example JS is ready! =) Mapbox CSS is ready! =) Error (JS) undefined  The line with the content Mapbox Example JS is ready! =) is from the example.js file. I have checked the files are OK by opening them in a browser window in the Salesforce URL, and everything looks fine, but as I am not getting any details about the error I do not know what can I do.   The contents of the failing JS library can be found here: . Any help would be much appreciated!

Components often seem to work with external libraries until the Locker Service is enabled. What libraries work with locker service enabled and where can I go to find out?


I do not understand the concept of convolution. If possible could you please explain in layman terms so that I can solve this question.   What is the h(t)?

I am having trouble understanding the concept of convolution. I get the mathematical idea behind it. I am able to evaluate that the convolution of the following problem  is $$f*g(t) = {0,\ \ t <= -1,\ \ t >= 1;\\ t+1, -1 <= t <= 0;\\ 1 - t,\ \ 0 <= t <=1}$$ However, what exactly is happening to the signal on more physical level?


Our Analysis I lecturer in his last lecture for the course gave us a problem to think about. I've been thinking about it for a while and has been bothering me for some time. It looks like a generalisation of a theorem( or lemma) in the real 1D case.   The problem is as follow:     Let $(a_n)$ be a complex sequence tending towards $0$. Show that there exists a sequence $\delta_n\in\{-1,1\}$ for all $n$ such that $\sum\limits_n\delta_na_n$ converges.   This is true in the case for real sequence.  My only vaguely hopeful line of attacking the problem is to reduce it down to a finite case problem as follows. Suppose we have $A=\{a_i:n\le i\le m\}$ such that $a_i\le\epsilon$ for some $\epsilon$.  Then I wish to show that I can choose $\delta_n$ such that the partial sum is always bounded by some multiple of $\epsilon$ (say $\sqrt2$ or possibly $2$). I suspect this is true but I'm not entirely sure how one goes about doing this since the size of our set A is arbitrary.

I am trying to figure this out:  $\mathscr{S}=\big\{(a_n),(b_n),\dots \big\}$ is a finite set of real, null sequences. Does there exist a sequence $(\epsilon_n)$, where $\epsilon_k=\pm 1$ for each $k$, such that: $$\forall\;(x_n)\in\mathscr{S}:\quad \sum_n \epsilon_n x_n<\infty\;?$$  A special case of this problem was posed by one of my lecturers: does every null sequence in $\mathbb{C}$ admit a sequence $(\epsilon_n)$ of signs such that $\sum\epsilon_nz_n$ converges?   The answer is yes. We can always choose signs so that $|\epsilon_1z_1+\cdots\epsilon_nz_n|\leq \sqrt{3}$ for all $n$, with some assumptions on $|z_n|$.  The geometric nature of the proof prevents me from generalising though. Any ideas how to deal with the general case?


New install Ubuntu 12.04 64 bit is painfully slow and freezes on a Dell 5150 desktop. It has dual core 2.8 GHz Pentium 4 processors and 1 GB RAM. Usage is over 700 MB with just the desktop running.  I installed using Wubi and used the 64 bit kernel by mistake. Our other machine is flying with the 32 bit and has 2 GB RAM. Could the 64 bit be the reason for the freezing? Would upgrading the RAM alone fix it? How could a reinstall of the 32 bit be done - would Wubi simply overwrite the previous installation ?  Alternatively am I barking up the wrong tree entirely. My technical knowledge is zero so please go easy - but I do love Linux. Wish I had found it years ago. Graphics from pci devices in hardinfo  Good machine 32 bit. Intel 82G33/31 memory 512KB 256MB(32bit prefetch) 1MB (32bit non prefetch) Slow machine 64 bit  AMD/ATI RV370 (no memory entry) 32 MB prefetch  64kB non prefetch

What is the difference between 32-bit and 64-bit Ubuntu? I've heard the 64-bit platform performs better and can detect more than 4GB of RAM. Also, while some apps haven't ported to 64-bit yet, ia32-libs lets a 64-bit machine run them.  If so, why not promote 64-bit over 32-bit?


I often face this question. A friend gives me a lot of used modems and routers, but they usually don't come with a power adapter.  Currently, I'm trying to use a router that is specified to work with a 12VDC/0.5A, but the only power supply I have that fits it is 5VDC/0.85A. And of course I could look for an appropriate adapter, but since I got a lot of 5V adapters, I'd like to try.  Thanks

Power supplies are available in a wide range of voltage and current ratings.  If I have a device that has specific voltage and current ratings, how do those relate to the power ratings I need to specify?  What if I don't know the device's specs, but am replacing a previous power supply with particular ratings?  Is it OK to go lower voltage, or should it always be higher?  What about current?  I don't want a 10 A supply to damage my 1 A device.


The US embassy in Mumbai banned me in 2015 for giving wrong information about my marriage. I want to know how many years I'm banned for. How can I know?

A Jamaican committed marriage fraud about 30 years ago by marrying a US citizen in a marriage where the groom was paid a certain amount of money to marry her. The groom got in legal trouble for an unrelated matter, and the marriage fraud was discovered and the family friend was deported back to Jamaica. She no longer has any paperwork involved with the deportation and she can’t remember any of the details. I do not know if she simply agreed to return to Jamica when the fraud was discovered, or if she made any attempts to mount any type of legal defense in the case. I do know that she was cooperative with the immigration authorities and that they did not have to come looking for her. She would like to come the USA for a two-week visit. The main purpose of the visit is for her to visit a friend (US citizen) who is terminally ill.  I have been looking at 8 U.S.C. 1182 and from my reading of it, it would seem that she would not be admissible to the US because of the previous immigration fraud. My understanding is based on the section that says:     In general.-Any alien who, by fraud or willfully misrepresenting a material fact, seeks to procure (or has sought to procure or has procured) a visa, other documentation, or admission into the United States or other benefit provided under this Act is inadmissible.   What’s not clear to me is if this means that she would be inadmissible permanently or if this would be subject to the 10 year limit.  Can anyone help provide some clarity on this?  If the ban is not permanent are there any tips to being able to increase her chances of being able to get a visa.  She intends to honestly answer all questions during her application process for a visa.


In Java, is it faster to iterate through an array the old-fashioned way,  for (int i = 0; i < a.length; i++)     f(a[i]);   Or using the more concise form,  for (Foo foo : a)     f(foo);   For an ArrayList, is the answer the same?  Of course for the vast bulk of application code, the answer is it makes no discernible difference so the more concise form should be used for readability. However the context I'm looking at is heavy duty technical computation, with operations that must be performed billions of times, so even a tiny speed difference could end up being significant.

What, if any, is the performance difference between the following two loops?  for (Object o: objectArrayList) {     o.DoSomething(); }   and   for (int i=0; i<objectArrayList.size(); i++) {     objectArrayList.get(i).DoSomething(); }


I've used unattended and scheduled updates via root cron and am looking to perform updates on a larger scale (using command line: non gui).   Ideally it would download the updates from the repositories once and share a local copy of the updates amongst the machines.  How to keep an office or cluster of machines up to date in a download efficient manner?

I have multiple Ubuntu machines at home and a pretty slow internet connection, and sometimes multiple machines need to be updated at once (especially during new Ubuntu releases.)  Is there a way where only one of my machines needs to download the packages, and the other machines can use the first machine to get the debs?  Does it involve setting up my own local mirror?  Or a proxy server?  Or can it be made simpler?


My book states that the expected value of the product of two independent random variables equal the product of their expected values. Why cannot one use this to give the following?  $$E(X \cdot X) = E(X) \cdot E(X) = [E(X)]^2$$  Of course, this is incorrect, as if this were true the variance would always be 0.

I wish to use the  to calculate the variance of a normal-distributed function. For this, I need the expected value of $X$ as well as the one of $X^2$. Intuitively, I would have assumed that $E(X^2)$ is always equal to $E(X)^2$. In fact, I cannot imagine how they could be different.  Could you explain how this is possible, e.g. with an example?


I am  newbie to all this and I learned that electrons can be wave as well as particles.  I don't have problem with the particle thing but how is it a wave?  Isn't the wave just a path of energy travel.   For example: waves in string is a path of energy travel. Then how can electron be somethings like this?  Am I misinterpreting the term wave? Or is there something else?  Are waves also made up of particles? Please explain in simple words.

I often hear about the wave-particle duality, and how particles exhibit properties of both particles and waves. However, I wonder, is this actually a duality? At the most fundamental level, we 'know' that everything is made up out of particles, whether those are photons, electrons, or maybe even strings. That light for example, also shows wave-like properties, why does that even matter? Don't we know that everything is made up of particles? In other words, wasn't Young wrong and Newton right, instead of them both being right?


I've had 40 of these errors in the last 7 days.  Can anyone give an explanation of the error and what I might do to correct it?  I'm running Windows 7 Ultimate 64 bit.  As a possibly important aside I'm runnning a copy of Windows 7 that I've yet to activate (still trying to find the damn code before I cough up dough for the new one.)

I'm running Windows 7 RTM 32-bit.  I'm getting the following error in my event log every second or so:     Session "Circular Kernel Context   Logger" failed to start with the   following error: 0xC0000035    Source: Kernel-EventTracing Level: Error User: SYSTEM OpCode: Start   Any ideas what would be causing this?


I work for a magazine and every so often we get ads (PDF format) that run through the pre-flight process with no errors. I will export a PDF with the ads out of InDesign and these boxes appear. This does not show up when we go to print, but we have an online edition which has the boxes. Does anyone know what causes this? Thanks!

I am creating a PDF file from InDesign and sometimes(90% of the times) when I export my work from InDesign into a PDF file a strange annoying 1px line appears(view immage) at the edge of the document... Did you ever had this problem? Why does it appear ?


I have display html on page using jquery-ajax call. But javascript on that page not working for html added from jquery-ajax response. I tried "async:false " but this one working for on window load. I want to make it working for Click event as well.  Is there any solution to use existing javascript for appended or replaced html on click event?

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.


I have this RegEx:  ('.+')   It has to match character literals like in C. For example, if I have 'a' b 'a' it should match the a's and the ''s around them.  However, it also matches the b also (it should not), probably because it is, strictly speaking, also between ''s.  Here is a screenshot of how it goes wrong (I use this for syntax highlighting):   I'm fairly new to regular expressions. How can I tell the regex not to match this?

I have this gigantic ugly string: J0000000: Transaction A0001401 started on 8/22/2008 9:49:29 AM J0000010: Project name: E:\foo.pf J0000011: Job name: MBiek Direct Mail Test J0000020: Document 1 - Completed successfully  I'm trying to extract pieces from it using regex. In this case, I want to grab everything after Project Name up to the part where it says J0000011: (the 11 is going to be a different number every time). Here's the regex I've been playing with: Project name:\s+(.*)\s+J[0-9]{7}:  The problem is that it doesn't stop until it hits the J0000020: at the end. How do I make the regex stop at the first occurrence of J[0-9]{7}?


I did solve, I got four solutions, but the book says there are only 3.  I considered the cases $| x - 3 | = 1$ or $3x^2 -10x + 3 = 0$.  I got for $x\leq 0$: $~2 , 3 , \frac13$  I got for $x > 0$: $~4$   Am I wrong?  Is $0^0 = 1$ or NOT?  Considering the fact that : $ 2^2 = 2 \cdot2\cdot 1 $   $2^1 = 2\cdot 1$   $2^0 = 1$   $0^0$ should be $1$ right?

Could someone provide me with a good explanation of why $0^0=1$?  My train of thought:  $x>0$  $0^x=0^{x-0}=0^x/0^0$, so  $0^0=0^x/0^x=\,?$  Possible answers:   $0^0\cdot0^x=1\cdot0^0$, so $0^0=1$ $0^0=0^x/0^x=0/0$, which is undefined   PS. I've read the  on mathforum.org, but it isn't clear to me.


My question  was silently deleted by the community bot for lack of activity and votes. I've revised it and would like to reactivate. I voted to undelete but  that it doesn't appear in the review queue, so I'm forced to go to Space SE's chat room to beg for undelete votes. Questions:  Is this the intended way for this to work, one has to appeal for undelete votes in chat rooms or perhaps by flagging for moderator assistance? Was I notified of the deletion, or is my recollection correct that it happened without any notification to me?  note: I'm not requesting undelete votes or un-deletion here, I'm just trying to understand how the site works, thanks!

What circumstances can cause a question or answer to be deleted, and what does that actually mean?    How can a post be deleted? When can't I delete my own post? Can I still see my post even after it's deleted? Can I see a list of my deleted posts? How can I undelete one of my posts? What does deletion mean for a post? How do votes to delete work? What are the criteria for deletion? What else should I know about deleted posts? If I flag my question with a request to delete it, what will happen?       For more information, see the articles about  and  in the .


Today the Hot Network Questions list includes questions from several per-site metas:    (in case the election needed more visibility?)  (not especially hot, even)     (Maybe more; I didn't review all 100.)  Most hot site issues are hot site issues and don't benefit from broader exposure.  I trust this is a bug and not intended behavior?

At this moment there are 4 meta-site questions on the HNQ list:    (World Building Meta)  (Meta StackOverflow)  (Workplace Meta)  (Mathematica Meta)   When I first saw it, I only saw the SO Moderator question, so I assumed that this was a one-off special thing for the election; but now we've got four questions crept in. Was this an intentional change, or a bug?


What is the difference between these two sentences:   You should go to school.  You must go to school.    And when should I use them?

What is the difference between "should" and "must"?  e.g. "They should have called the police." Can I use "must" in that sentence or not?  e.g. "You should read his new book." How about this sentence?


I am amateur photographer and I don't plan any variants commercial use of my photos. But I want to evolve to take better pictures.  I started from the purchase of the camera Sony Nex-5 (with KIT-lens 18-55)  Then I added postprocessing of my pictures (white balance, contrast, brightness, etc.). I'm postprocessing of JPEG-files, often HDR.  Also I tried a bit of other lenses (cheap - Helios) and long-exposure.  Now I feel certain stagnation, I can't do better using the same approach.  Purchase better camera or lens would open up new possibilities, but now I cant much to spend on my hobby.  Will I get much better pictures if I start to work with RAW instead of JPEG?

In general shooting in RAW format uses a lot more file storage than JPEG. What am I gaining when shooting RAW? Besides file size are there any downsides to shooting RAW?


What's the difference between this:  List<String> list = new LinkedList<String>();   and this?  LinkedList<String> list = new LinkedList<String>();

would report a violation for:  ArrayList<Object> list = new ArrayList<Object>();   The violation was "Avoid using implementation types like 'ArrayList'; use the interface instead".  The following line would correct the violation:  List<Object> list = new ArrayList<Object>();   Why should the latter with List be used instead of ArrayList?


Based on the images that are shown right after the Snap, there seems to be a lot of deaths that are side effects of the snap. Everyone who was on a plane when the pilot went away, people in cars, and similar situations. Those were, strictly speaking, natural deaths, so the question is: were those deaths reversed and brought back by Banner's snap or would they stay dead? I’m not taking here about people that died before the Snap (i.e. Vision, etc) but about people that died after the Snap, because of the Snap, but without being “willed out of existence”.

In Avengers: Endgame, after recovering the 6 Stones, Hulk snaps his fingers and brings back all the lost characters but he can’t bring back Black Widow or Gamora as the sacrifices for the Soul Stone are final. However, he explicitly states he tried.  Since those characters had not died because of the snap it’s clear the resurrection part doesn’t need to be limited to just the snapped out people, do we have any information about all the people who died for reasons other than the snap? Were they resurrected too or are they still death?  I’m thinking here of Vision, Loki, the people from Xandar, the Dwarves, all the casualties on the fight with Thanos, etc.


I use Ubuntu Gnome 14.04 LTS, and I'm wondering if I can safely upgrade to 16.04 LTS.  Do I just click upgrade on the software upgrade utility, or should I run sudo apt-get dist-upgrade?  The last time I tried to upgrade from 12.10 to 14.04 LTS, my computer complained and gave me no end of issues.

Question is about Ubuntu release process. Are migrations from n to n+1 releases expected?  Assuming we have server with installed Ubuntu 14.04 LTS. Will it be smoothly upgradable to Ubuntu 16.04 LTS via apt-get upgrade ?  Assumptions:   scope is software therefore we assume that given hardware is supported on both releases (upgrading from and to) that's why, always before upgrade you are asked to make backup to be able to revert in case of failure


Hi I am new to this site and linux as well. Installed ubuntu on my dell inspiron 3543 laptop which already had windows 10. After successfully installing ubuntu and at the first reboot, It started to boot windows 10 as usual and there was no option to select between ubuntu and windows 10.  Please help. Many thanks.

I'm absolutely new to Linux. I would like to know how to install Ubuntu alongside the pre-installed Windows 8+ OS.  Should I do it with Wubi, or through the Live USB/DVD?  What steps do I need to take to correctly install Ubuntu?


I am from Canada. My flight will depart from Toronto to Chicago, United States, then Chicago to Asia. Do I need some kind of US transit visa to transfer airplanes? Or transiting to a different airport?

In Europe usually you don't need to go through immigration to change planes (unless you are entering/exiting Schengen). Is it the case in the US as well? May I catch a connecting flight on one of the US airports if I don't have US visa?


Let's say someone finishes their honours degree and would like to do their PhD.  However, the scholarship offers they receive aren't at the places they'd have hoped.  My question is whether it is worth doing an additional year to finish their masters with the hope of getting into their preferred university.  My personal situation is that I would like to study in Singapore or Hong Kong, but only received offers from Australian universities.

I am now in the middle of my master's degree and I plan to graduate in August 2015. I currently study in Germany and for most engineering students here it is common to finish the five-year program (3 or 3.5 years for the bachelor's degree and 1.5 to 2 years for the master's). I'm thinking about applying for robotics PhD programs at different US universities but I noticed that most of them have a deadline in December for programs starting 9 months later. I don't have any publications in any international journals because in Germany this is mostly done by PhD students. But I have worked a lot during my studies (1 year internship, part-time research in university).  I don't want to lose one year waiting to start my PhD but in the same time I think that my master thesis will be a great asset while applying for such a program, especially when I will be willing to continue my research and PhD thesis in the same field as my master thesis. Do you think I should take the GRE and apply for next December or wait until getting my master's degree? And how this would influence the selection process.


I am attempting to install Packet Tracer on my machine running Ubuntu 20.04, and I keep running into the same issue. While going through several different tutorials on installing Packet Tracer 7.2.2, I run into the same problem: I keep getting the 404 Error message when I get to the part of adding multiarch-support. The line in terminal that is causing me the errors is: wget http://archive.ubuntu.com/ubuntu/pool/main/g/glibc/multiarch-support_2.29-0ubuntu2_amd64.deb  Does anyone have any idea how to correct this? Or what am I doing incorrectly? Thanks for the help!

I am trying to install Packet Tracer 7.3 (latest version) on Ubuntu 20.04 but do not succeed to so so because of two dependencies which are not installable ("libdouble-conversion1" and "qt-at-spi").  However I successfully installed the previous version (7.2.2) which was available in an Ubuntu installer format (.run file) but I nothing happens when I run it from my gnome desktop.  I am quite a newbie in Linux so I appologies if answers are obvious...  Thanks in advance ;-)  Denis


how do I check if the following set of vectors $[3+i,0,i],[0,1+3i,2],[6+2i,3+9i,6+2i]$, or in general any set of complex vectors span the space $\Bbb C^3$, not using any matrix methods?  Thanks for helping out!

I want to know if the set $\{(1, 1, 1), (3, 2, 1), (1, 1, 0), (1, 0, 0)\}$ spans $\mathbb{R}^3$. I know that if it spans $\mathbb{R}^3$, then for any $x, y, z, \in \mathbb{R}$, there exist $c_1, c_2, c_3, c_4$ such that $(x, y, z) = c_1(1, 1, 1) + c_2(3, 2, 1) + c_3(1, 1, 0) + c_4(1, 0, 0)$.  I've looked around the internet, but all the answers I found involve setting up a matrix and finding the determinant, and I can't do that here because my matrix isn't square. What am I missing here?


I'm trying to learn java for AP computer science A and thought I would try to make a simple remainder calculator. This calculator prompts the user to enter a number and it will give the remainder when divided by 1 (it's not a good calculator). Here is my program: public class Unit2Lab2 {     public static void main(String[] args) {         Scanner scanner = new Scanner(System.in);         float Value = scanner.nextFloat();         float a = Value % 1;         System.out.println(a);     } }  It was all fine and dandy but when I tested it out by plugging in the value of 15.98, the result I got was 0.999999976. I don't know why this happened but I managed to circumvent the issue by using the df.format command I found online. I still want to know if there is a way to stop the remainder function from getting wonky.

public class doublePrecision {     public static void main(String[] args) {          double total = 0;         total += 5.6;         total += 5.8;         System.out.println(total);     } }   The above code prints:  11.399999999999   How would I get this to just print (or be able to use it as) 11.4?


Source code  I'm working on a  which brings 5 files:   cassio.bib: bibliography comandos.tex: a rich set of commands for easiness of typing tg.tex: document's source code tg.pdf: generated PDF Makefile: compilation tool   To compile it, type make tg.pdf to generate tg.pdf.  The problem  I have a problem related to algorithm environment in algorithm2e package.  Within tg.pdf, plase take a look at page 33. This algorithm should be placed within section (5.2) (in the page 32) and right before section (5.3). The corresponding code happens at line 1976 in the tg.tex file.  A similar problem  A similar problem happens at tg.pdf (page 43). This algorithm and the subsequent text (Parte I: Apêndice) should be separated by a page break; i.e., they should not appear in the same page.  My goal is to force algorithm to be rendered in the order it is written in tg.tex. Could anyone help me figuring out where is the problem?

How to influence the position of float environments like figure and table in LaTeX?   This is a general question and should collect useful answers for all users. I hope we can use this as a reference


The title explains most of it. I have a lenovo G580, originally windows 8, since I upgraded to windows 10 I got a crash report. I tried downloading Intel's upgrading graphics card software, it didn't work(That's how it's different from other questions!!). What should I do to fix it?     Here is my crash report (the header is normal text with dashes under it):    ---- Minecraft Crash Report ----   // This is a token for 1 free hug. Redeem at your nearest Mojangsta: [~~HUG~~]  Time: 10/3/15 10:59 AM   Description: Initializing game  org.lwjgl.LWJGLException: Pixel format not accelerated       at org.lwjgl.opengl.WindowsPeerInfo.nChoosePixelFormat(Native Method)       at   org.lwjgl.opengl.WindowsPeerInfo.choosePixelFormat(WindowsPeerInfo.java:52)       at org.lwjgl.opengl.WindowsDisplay.createWindow(WindowsDisplay.java:247)       at org.lwjgl.opengl.Display.createWindow(Display.java:306)       at org.lwjgl.opengl.Display.create(Display.java:848)       at org.lwjgl.opengl.Display.create(Display.java:757)       at org.lwjgl.opengl.Display.create(Display.java:739)       at ave.ap(SourceFile:534)       at ave.am(SourceFile:363)       at ave.a(SourceFile:310)       at net.minecraft.client.main.Main.main(SourceFile:124)     A detailed walkthrough of the error, its code path and all known details is as follows:   ---------------------------------------------------------------------------------------  -- Head -- Stacktrace:       at org.lwjgl.opengl.WindowsPeerInfo.nChoosePixelFormat(Native Method)       at org.lwjgl.opengl.WindowsPeerInfo.choosePixelFormat(WindowsPeerInfo.java:52)       at org.lwjgl.opengl.WindowsDisplay.createWindow(WindowsDisplay.java:247)       at org.lwjgl.opengl.Display.createWindow(Display.java:306)       at org.lwjgl.opengl.Display.create(Display.java:848)       at org.lwjgl.opengl.Display.create(Display.java:757)       at org.lwjgl.opengl.Display.create(Display.java:739)       at ave.ap(SourceFile:534)       at ave.am(SourceFile:363)    -- Initialization --   Details:   Stacktrace:       at ave.a(SourceFile:310)       at net.minecraft.client.main.Main.main(SourceFile:124)    -- System Details --   Details:       Minecraft Version: 1.8.8       Operating System: Windows 10 (x86) version 10.0       Java Version: 1.8.0_60, Oracle Corporation       Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation       Memory: 741648 bytes (0 MB) / 60702720 bytes (57 MB) up to 1037959168 bytes   (989 MB)       JVM Flags: 2 total; - XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G       IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0       Launched Version: 1.8.8       LWJGL: 2.9.4       OpenGL: ~~ERROR~~ RuntimeException: No OpenGL context found in the current thread.       GL Caps:        Using VBOs: No       Is Modded: Probably not. Jar signature remains and client brand is untouched.       Type: Client (map_client.txt)       Resource Packs:        Current Language: ~~ERROR~~ NullPointerException: null       Profiler Position: N/A (disabled)       CPU: <unknown>

Similar to  on the bugs in Minecraft, I would like a complete list of what error codes exist in Minecraft and how they occur, as well as how they can be resolved.


Microphone is not working in my Ubuntu 14.04.4 LTS. I've tried a bunch of ways that I picked from internet. alsamixer seems not updating the mic volume I've increased and is always zero on each reboot.    in the above screenshot Internal Mic Boost seems to zero on every reboot.  I've installed pavucontrol. There it seems internal microphone as unavailable. Microphone Plugged In is default selected option even I'm not using any other input devices.  In gstreamer-properties, the following are the configuration      Default Input    Plugin - Custom Device -  None Pipeline - autoaudiosrc   I've re-installed (twice) alsa and pulse-audio and other related sound libraries. I've disabled 'Allow Skype to automatically adjust my mixer levels'. Installed Audacity, and also some tweaks in alsa-base.conf, still could not resolve the issue.  I'm using Asus Zenbook UX305.

I have an internal microphone in my laptop. I think it uses Intel High Definition Audio. But I can't get it to work with Ubuntu. It doesn't work with either the Sound Recorder or Skype.  On the Input tab in 'Sound Preferences', I just see Internal Analog Input Device...