I know that this question has been asked before, but I still can't find a clear answer, I read here this question:  and a guy wrote: $\emptyset, \{1\}, \{2\}, \{1, 2\}, \{3\}, \{1, 3\}, \{2, 3\}, \{1, 2, 3\}, \{4\}, \ldots$, this would be the power set of $\mathbb{N}$ listed in a row, why would this create a bijection between $\mathbb{N}$ and this set? (which would prove that the power set of $\mathbb{N}$ isn't equinumerous with $\mathbb{R}$)? Or for example writing: $\{1\}, \{2\}, \{3\}, \{4\}, \ldots$ $\{1, 2\}, \{1, 3\}, \{1, 4\}, \ldots$ $\{1, 2, 3\}, \{1, 2, 4\}, \{1, 2, 5\} \ldots$ $\{1, 3, 4\}, \{1, 3, 5\}, \{1, 3, 6\} \ldots$ $\{1, 10, 11\}, \{1, 10, 12\}, \{1, 10, 13\} \ldots$ $\vdots$ $\{2, 3\}, \{2, 4\}, \{2, 5\}, \ldots$ $\{2, 3, 4\}, \{2, 3, 5\}, \{2, 3, 6\} \ldots$ $\vdots$ and then do the diagonalization thing that Cantor used to prove the rational numbers are countable:  Why wouldn't this work? P.s: I know the proof that the power set of a set has a larger cardinality that the first set, and I also know the proof that cantor used to prove that no matter how you list the real numbers you can always find another one that is not inside that list. I know the proof that the power set of $\mathbb{N}$ is equal to $\mathbb{R}$ as well, I'm not saying that my argument is correct and theirs is wrong, I'm just trying to understand why mine is wrong

I'm having trouble understanding Cantor's diagonal argument.  Specifically, I do not understand how it proves that something is "uncountable".  My understanding of the argument is that it takes the following form (modified slightly from the  article, assuming base 2, where the numbers must be from the set $ \lbrace 0,1 \rbrace $):  \begin{align} s_1 &= (\mathbf{0},1,0,\dots)\\ s_2 &= (1,\mathbf{1},0,\dots)\\ s_3 &= (0,0,\mathbf{1},\dots)\\ \vdots &= (s_n \text{ continues}) \end{align}  In this case, the diagonal number is the bold diagonal numbers $(0, 1, 1)$, which when "flipped" is $(1,0,0)$, neither of which is $s_1$, $s_2$, or $s_3$.  My question, or misunderstanding, is: When there exists the possibility that more $s_n$ exist, as is the case in the example above, how does this "prove" anything?  For example:  \begin{align} s_0 &= (1,0,0,\mathbf{0},\dots)\ \ \textrm{ (...the wikipedia flipped diagonal)}\\ s_1 &= (\mathbf{0},1,0,\dots)\\ s_2 &= (1,\mathbf{1},0,\dots)\\ s_3 &= (0,0,\mathbf{1},\dots)\\ s_4 &= (0,1,1,\mathbf{1},\dots)\\ s_4 &= (1,0,0,\mathbf{1},\dots)\ \ \textrm{ (...alternate, flipped } s_4\textrm{)}\\ s_5 &= (1,0,0,0,\dots)\\ s_6 &= (1,0,0,1,\dots)\\ \vdots &= (s_n \text{ continues}) \end{align}  In other words, as long as there is a $\dots \text{ continues}$ at the end, the very next number could be the "impossible diagonal number", with the caveat that it's not strictly identical to the "impossible diagonal number" as the wikipedia article defines it:     For each $m$ and $n$ let $s_{n,m}$ be the $m^{th}$ element of the $n^{th}$ sequence on the list; so for each $n$,      $$s_n = (s_{n,1}, s_{n,2}, s_{n,3}, s_{n,4}, \dots).$$      ...snip...      Otherwise, it would be possible by the above process to construct a sequence $s_0$ which would both be in $T$ (because it is a sequence of 0s and 1s which is by the definition of $T$ in $T$) and at the same time not in $T$ (because we can deliberately construct it not to be in the list). $T$, containing all such sequences, must contain $s_0$, which is just such a sequence. But since $s_0$ does not appear anywhere on the list, $T$ cannot contain $s_0$.      Therefore $T$ cannot be placed in one-to-one correspondence with the natural numbers. In other words, it is uncountable.   I'm not sure this definition is correct, because if we assume that $m = (1, \dots)$, then this definition says that "$s_n$ is equal to itself"&mdadsh;there is no "diagonalization" in this particular description of the argument, nor does it incorporate the "flipping" part of the argument, never mind the fact that we have very clearly constructed just such an impossible $T$ list above.  An attempt to correct the "diagonalization" and "flipping" problem:  $$s_n = (\lnot s_{m,m}, \lnot s_{m,m}, \dots) \quad \text{where $m$ is the element index and} \quad\begin{equation}\lnot s_{m,m} = \begin{cases}0 & \mathrm{if\ } s_{m,m} = 1\\1 & \mathrm{if\ } s_{m,m} = 0\end{cases}\end{equation}$$  This definition doesn't quite work either, as we immediately run in to problems with just $s_1 = (0),$ which is impossible because by definition $s_1$ must be $ = (1)$ if $s_1 = (0)$, which would also be impossible because...   Or more generally, with the revised definition there is a contradiction whenever $n = m$, which would seem to invalidate the revised formulation of the argument / proof.  Nothing about this argument / proof makes any sense to me, nor why it only applies to real numbers and makes them "uncountable". As near as I can tell it would seem to apply equal well to natural numbers, which are "countable".  What am I missing?


How is this possible, technically? What is the logic behind this?

Below is a visual proof (!) that $32.5 = 31.5$. How could that be?    (As noted in a comment and answer, this is known as .)


Very new programmer here, sorry if this sounds stupid. I'm doing an exercise of  in which I found that I needed to do something like this:  class Person(): """Just creates a person with name, address and email"""     def __init__(self, name, address, email):         self.name = name         self.address = address         self.email = email persons = {} #dictionary to store various persons as an address book, with each person's name as the key to their object def changeperson(): """This is going to be able to access any person in persons, and change their variables"""     persontochange = raw_input("What person do you want to change?")     thingtochange = raw_input("What do you want to change?")     result = raw_input("What should that be?")     #here assign to persons[persontochange].thingtochange the value of result, I don't know how   Sorry if this sounds stupid and for any problems with my English. Thanks for reading.

Suppose I have a python object x and a string s, how do I set the attribute s on x? So:  >>> x = SomeObject() >>> attr = 'myAttr' >>> # magic goes here >>> x.myAttr 'magic'   What's the magic? The goal of this, incidentally, is to cache calls to x.__getattr__().


this is my first post/question and I wanted to see if there is some plugin/way that I don't know of to get a c4d file to import to Blender or to convert c4d files to fbx without cinema 4d. If there is no current way to do so, who would like to team up with me to create a plugin to import c4d file contents into blender??  Hope someone can help me with this, Thanks for reading this regardless of if you can help or not ^^

How can I import a .c4d static model (Cinema 4d) on Blender? Is there any plugin could help me? I didn't notice anything on Internet.


I only have one partition created and i was thinking, if i wanna have Ubuntu and Windows, can Ubuntu create another partition for itself in the process of installing?

I'd like to see the full How-To on how to use manual partitioning during Ubuntu installation. The existing guides (at least those I found here) cover only automatic part and leave untouched the manual part (or extremely short and contain no pictures).  I'd like to cover such situations:     If your disk contains other systems:


This is my current code in Python. From here, I need to strip the gutenberg.txt of its punctuation. How would I go about this?   import bs4 import urllib.request  #make a string to record location loc = 'http://www.gutenberg.org/files/1155/1155-h/1155-h.htm' #create page object page = urllib.request.urlopen(loc).read() #create the soup object soup = bs4.BeautifulSoup(page,'html.parser') #save into text file  print(soup.prettify()) print(soup.get_text())  string = str(soup.get_text())  f = open("gutenberg.txt","w") f.write(string); f.close()

It seems like there should be a simpler way than:  import string s = "string. With. Punctuation?" # Sample string  out = s.translate(string.maketrans("",""), string.punctuation)   Is there?


works:  sudo iptables -A OUTPUT -m owner --uid-owner {USERNAME} -j REJECT   to block internet for a specific user. But it's not permanent.  What's the easiest way to make this persistent after a reboot, with newer systems (with systemd)?  Creating a specific .service file is always tricky and takes some time to figure out: one-shot? stoppable? forking? etc. and , so I was wondering what is the most natural way to persist a iptables rule with new systems.

I add this rule:  sudo iptables -t nat -A OUTPUT -d a.b.c.d -p tcp \        --dport 1723 -j DNAT --to-destination a.b.c.d:10000    When restart computer rules are deleted. Why? What I can do to make the rules persist?


When water is poured out in space, why does it always take a spherical ball-like shape?

Consider a drop of water floating in an inertial frame in STP air (e.g., the ISS). Intuitively, the equilibrium shape of the drop is a sphere.  How would one prove that? Is it equivalent to showing that the minimal surface area for a simply connected volume in $\mathbb{R}^3$ with a sufficiently smooth boundary is that of a sphere, i.e., the result of the isoperimetric inequality?


I am using Ubuntu 12.04 with a dual monitor setup.  I like Firefox to have a specific position and size on my screen. So I resize it and position it like I want it. But when I close and reopen it, it randomly resizes and positions itself as it wants.    Is there a way to make Firefox remember it's size and position?  I have tried compizconfig settings manager but this changes the default behavior of all firefox windows, including pop up dialog boxes.  I'm hoping there is a better method.  Thanks

When I log in Ubuntu, I would like all windows opened at previous session (terminal and Firefox mainly) to be re-opened automatically at the same size and position.  How to proceed?


Filezilla was acting weird with version 3.21, which is pretty old; the current one is 3.30. So, I decided to update it but it looks like this is not possible. After spending hours trying it, I returned to the old version 3.21.  Is there any possible way to update it , or is there any other FTP client that works better (and can be updated)?  Update:  I run Ubuntu 16.04 TLS, the post about repositories not having latest versions is not relevant because I need procedures to follow, not an open discussion.

How can I install the latest  FileZilla from its official ?  I can find FileZilla from my software centre and install it. But it is version 3.24.0. While the latest is 3.25.2.  Can I upgrade the version 3.24.0 that I have already installed to 3.25.2?  I always wonder how to install from its official site, but it is not a .deb. It looks like the source files of FileZilla that you need to compile or build. But how can I do it?  Any ideas?  This is from the site but it is just not very helpful to me:     Installing on GNU/Linux and other Unix(-like) systems      It is recommended that you use the package manager of your   distribution. If you're using GNU/Linux, you can also try using the   precompiled binaries. After extracting the files to any location   (location does not matter, FileZilla can detect its own installation   prefix), you can start the program using the filezilla executable in   the bin/ subdirectory. Please note that due to differences in   distributions, the provided binaries might not work on your system.   Alternatively you can also compile FileZilla from source.


If you're traveling on a US passport leaving Dubai returning to the USA with a 2 hour layover changing planes in Doha, Qatar, do I need a Transit Visa?

My fiance is traveling from Dubai back to the USA with a layover in Doha, Qatar for two hours.    Does he need a Transit visa?


This sample code  DateTime date = new DateTime(2020, 01, 27); string str = Newtonsoft.Json.JsonConvert.SerializeObject(date, Newtonsoft.Json.Formatting.None,     new Newtonsoft.Json.JsonSerializerSettings() {          DateFormatHandling = Newtonsoft.Json.DateFormatHandling.IsoDateFormat });   returns str = "\"2020-01-27T00:00:00\"" - so the string's content is surrounded with quotes (here written in escaped form as the debugger does).  But I want only the date and time in ISO format. Why are there quotes? How can I avoid them without removing them afterwards?  I already looked for all serializer options, but didn't found the one helping me...

Given:  DateTime.UtcNow   How do I get a string which represents the same value in an -compliant format?  Note that ISO 8601 defines a number of similar formats. The specific format I am looking for is:  yyyy-MM-ddTHH:mm:ssZ


Hi I have to apply dark theme flair but it is not updated (Reputation) from last 2 days.  Show image Below:

There is an update issue with the new flairs. Yesterday I replaced all my flair snippets with the new ones, but the rep value on the "default theme" has not been updated. Here is a screeny:    The other themes show the correct value whereas the default one does not.


Everything in Minecraft is red & blue and makes it hard to see.  It's like one of those red & blue 3D movies. How do I change it back to normal?

I have updated my drivers, updated java, restarted my computer and downloaded the game several times. When I try to play the game everything is duplicated in opaque red and blue. Does anyone else have this problem?


Well let's just say that this used to work fine then I started it up again today and now it doesn't....  pin is 1234 and no matter what I do it says it's not valid...  and yes I know that it doesn't check the third time. I have to fix that too:      import java.util.Scanner;      import java.util.Scanner;     public class ATM   {        public ATM()        {           Scanner console = new Scanner(System.in);            final String pin = "1234";           String userPin = "";           int pinCount = 1;           boolean error = false;            do{               System.out.print("Enter PIN: ");               userPin = console.nextLine();                if (pinCount == 3) {                   System.out.println("Bank account is blocked");                   break;               }               else if (userPin.length() < 4 || userPin.length() > 4) {                   error = true;                    pinCount += 1;               }               else if (isNumeric(userPin) && userPin == pin && pinCount < 3) {                   System.out.println("Your PIN is correct");                   break;               }               else{                   System.out.println("Your PIN is incorrect");                   error = true;                   pinCount += 1;               }           }while(error);                 }        public static boolean isNumeric(String str)         {            try             {               double d = Double.parseDouble(str);             }             catch(NumberFormatException nfe)             {               return false;             }             return true;           }   }   Don't ask me why I have it split:  public class ATMtest  {     public static void main(String[] args)      {         ATM atm = new ATM();     }  }   Any help would be greatly appreciated.

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?


The quantum state of an electron in a hydrogen atom is specified by 4 quantum numbers: $n$ , $\ell$, $m_\ell$, $m_s$ which can take the following values: $$n =  1, 2, 3, ... $$ $$\ell = 0, 1, 2, 3, ..., n-1 $$ $$m_\ell =  -\ell , -(\ell-1), ... , (\ell-1), \ell$$ $$m_s = +\frac{1}{2} ,-\frac{1}{2} $$ If I'm not mistaken, the condition that specifies that specifies the highest $\ell$ value can be found when solving the radial Schrödinger equation.  Therefore, why can we also apply the same rules for determining the electronic configuration of an atom with many electrons? Wouldn't the potential energy term in the radial equation be altered by the presence of all of the other electrons, hence resulting in a different relationship between $n$ and the highest possible value of $l$?

The solutions of the Schrödinger equation for hydrogen are the "electronic orbitals", shown in this picture:  ()  They have the following degeneracy structure:  ()  It is often said that atoms in other elements simply have more electrons "filling up" the orbitals in increasing order of energy, as required by the Pauli exclusion principle.  This is somewhat confirmed via xray spectroscopy:  ()  But why would non-hydrogen atoms have the same orbital degeneracy structure as hydrogen, if the actual Hamiltonian is different from one atom to another?


Recall that from Vizing's theorem, the chromatic index $\chi'(G)$  can only be either $\Delta(G)$ (we call the graph Class 1) or $\Delta(G) +1$ (Class 2). My question is regard to determining the class of a given complete graph $K_n$. I don't know how complicated this question is, so it is very appreciable if there is a suggestion for me to tackle this.

If G is a graph containing no loops or multiple edges, then the edge-chromatic number $X_e(C)$ of G is defined to be the least number of colours needed to colour the edges of G in such a way that no two adjacent edges have the same colour.  How to find edge-chromatic number :  1)Complete Graph($K_n$)  [I know $k_n$ is (n-1)regular and if n is even then edge-chromatic number of $k_n$ is n-1 and if n is odd then edge-chromatic number of $k_n$ is n,but how to prove it??]  2)Wheel($W_n$)


I am facing issues in uploading an image to my answer. I have cleared cache and cookies and tried in another browser. But the issue still persists. My image size is less than 2MB.  Here is my :    Is anybody facing the same issue?

When I try to upload an image, I'm presented with the following dialog box,    The dialog box does not allow uploading either from my computer or by posting a link.  This happens only on Chrome browser (running on Windows). Clearing cache and cookies, and restarting computer do not resolve.  Is this just my computer? Or is this a site-wide bug?  Additional info:  Clicking on 'click' to upload does nothing. Dragging an image onto dialog redirects me to the file location on my computer. Clicking 'Add picture' redirects me to http://[SE-domain].com/upload/image?https=true.  UPDATE: A Norton extension for Chrome was the source of the problem.


Let $\Phi$ be the class of all fonctions  $\phi$ (let's say from $\mathbb{R}^+$ to $\mathbb{R}^+$) such that: For each sequence $\{t_n\}\subset \mathbb{R}^+$ that converges, the sequence $\{\phi(t_n)\}$ converges also.  Is there any specific name for this class of functions?  It will be interesting to see some interesting examples/counterexamples.

Pugh, "Mathematical Analysis", exercise 2.17:     Assume $f : M \to N$ is a map from one metric space to another which satisfies the following condition: for every convergent sequence $(a_n) \subset M$, the sequence $(f(a_n)) \subset N$ converges. Prove that $f$ is continuous.   (I know that if $f$ commutes with limits then the answer is affirmative, but I can't prove it with that hypothesis).


I'm sure everyone already thought about this at least one time. Why matrix multiplication is not defined the way showed below?  $$\left( \begin{array}{ccc} a_{11} & a_{12} & \ldots \\ a_{21} & a_{22} & \ldots \\ \vdots & \vdots & \ddots \end{array} \right) \cdot \left( \begin{array}{ccc} b_{11} & b_{12} & \ldots \\ b_{21} & b_{22} & \ldots \\ \vdots & \vdots & \ddots \end{array} \right) = \left( \begin{array}{ccc} a_{11}\cdot b_{11} & a_{12}\cdot b_{12} & \ldots \\ a_{21}\cdot b_{21} & a_{22}\cdot b_{22} & \ldots \\ \vdots & \vdots & \ddots \end{array} \right) $$  I know this definition has it's limitations. The product only works with same order matrix and any matrix with some zero entry won't be invertible. But this definition is associative, commutative, has identity element, the distributive works, is simpler and more intuitive.  I have no problem about the classic definition, but this definition also has good properties, why it is never used?

I was just wondering why we don't ever define multiplication of vectors as individual component multiplication.  That is, why doesn't anybody ever define $\langle a_1,b_1 \rangle \cdot \langle a_2,b_2 \rangle$ to be $\langle a_1a_2, b_1b_2 \rangle$?  Is the resulting vector just not geometrically interesting?


We have a WAMP based server set up. php.ini is set up with the following:  session.gc_maxlifetime = 60*60*12 session.save_path = "d:/wamp/tmp"   The problem we are facing is that session files inside the tmp folder are being sporadically deleted and we can't tell why. Sessions will last anything from about 10 minutes to 40 minutes, when they should be lasting 12 hours.  This is a virtual host environment, but none of the code we use in these sites overrides this setting (with ini_set, apache config PHP values or otherwise) so we can't see why they are being deleted. There are also no scheduled tasks deleting the files.  Is there a way to successfully figure out why gc_maxlifetime is being ignored? For the record, I changed one of our sites to use session_save_path('D:/wamp/tmptmp'); temporarily just to double check it was the garbage collection, and session files remain in there untouched - though admittedly this doesn't give really many more clues.

This is a  about  the use of a *AMPP's stack.    I recently had a talk with some experienced people and they suggested to me not to use a WAMP stack, and instead install apache, mysql and php separately.  I don't understand why they have suggested this, though, so can anyone tell me?  Is there a particular disadvantage of WAMP, or a particular advantage to installing all of them separately?  Since a WAMP stack itself is composed of apache, mysql and php, then what's the difference between using the WAMP stack and installing them all separately?


I need to split words by space separated in java, so I have used .split function in-order to achieve that like as shown below   String keyword = "apple mango "; String keywords [] = keyword .split(" ");   The above code is working fine but the only is that I sometimes my keyword will contain keyword like "jack fruit" , "ice cream" with double quotes like as shown below  String keyword = "apple mango \"jack fruit\" \"ice cream\"";   In this case I need to get 4 words like apple, mango, jack fruit, ice cream in keywords array  Can anyone please tell me some solution for this

I'm new to regular expressions and would appreciate your help.  I'm trying to put together an expression that will split the example string using all spaces that are not surrounded by single or double quotes. My last attempt looks like this: (?!") and isn't quite working. It's splitting on the space before the quote.  Example input:   This is a string that "will be" highlighted when your 'regular expression' matches something.   Desired output:  This is a string that will be highlighted when your regular expression matches something.   Note that "will be" and 'regular expression' retain the space between the words.


Can the spectrum of a quantum mechanical operator contain both real and complex numbers?

Why can't we measure imaginary numbers? I mean, we can take the projection of a complex wave to be the "viewable" part, so why are imaginary numbers given this immeasurable descriptor? Namely with operators in quantum mechanics, why must measurable quantities be Hermitian, and consequently real?


We know that there are bijections between $[0,1]$, $(0,1)$ and $\mathbb{R}$. But my question is can we obtain a continuous bijection between $[0,1]$ and $(0,1)$, and between $[0,1]$ and $\mathbb{R}$?  I think there will not exist but I am not sure.

Does there exist a continuous bijection from $(0,1)$ to $[0,1]$? Of course the map should not be a proper map.


[root@host dir1]# ls -lrt total 412 -rw-r--r-- 1 root root  13747 Jun  3 16:01 -lang?[5~?[5~?[5~?[5~?:q!   We tried different ways and they don't work.  [root@host dir1]#  ls -lrt | tail -1 | awk '{print $9}' | xargs -I file rm file rm: invalid option -- 'l' Try `rm ./'-langq!'' to remove the file `-lang\033[5~\033[5~\033[5~\033[5~\033:q!'. Try `rm --help' for more information.  [root@host dir1]# rm ./'-langq!'' > ^C

Somehow a file named -]???????q got created on my terminal. I tried  rm -f "-]???????q"  (in double quotes), but it did not get deleted. (Error::  rm: invalid option -- ]).  How do I delete it?


Given the statement $X \implies Y$ and $Y \implies X$, we have the common notation $X \iff Y$. Ok so is there an opposite of this concept? Suppose I have $X$ doesn't imply $Y$, nor does $Y$ imply $X$...i.e. neither implies the other. What would you say or write for this? Whats the correct word?

Let a statement P is "X is true if and only if Y is true". What is the negation of P? I am little confused. It seems that digital equivalent of this statement is P = X and Y. Hence negation of P is (not X) or (not Y) i.e. Either X or Y is false. Am I right guys?


I need pointing to an accurate up to date method to install Wordpress. I also need details on setting up Apache for it. There is NO official help or support that I can find. Is there anything else beyond the virtual host file and the /etc/hosts edit? How exactly should they be configured? My ip just leads me to the Apache test page, how to I get it beyond that into the sub directory?

I am trying to install Wordpress on Lubuntu. I followed the instructions . Including PHP Apache and MySQL setups. Apache and MySQL appear to be running fine.  However, when I go to http://localhost/blog/, I get the following error:     Neither /etc/wordpress/config-localhost.php nor /etc/wordpress/config-localhost.php could be found.   Ensure one of them exists, is readable by the webserver and contains the right password/username.


I have a div which completely created on the fly when the page is loaded and this div is visible to the user and in firebug but when i view the page source its not available.. the content within the div changes dynamically.  im trying to bind a click event to it so when someone clicks on that div to alert a message..  i have go through almost all the suggestions but none of them work  my dynamic div
Hello this a mootoo test
   Tested JQuery functions  $(document).on('click', ".mootoo", function() {       alert("clicked"); });    $('.mootoo').on('click',function() {    alert("clicked");     });    $('.mootoo').live('click',function() {    alert("clicked");     });   Can someone please tell me what am i doing wrong?    actually i cant find the JQ code where it generates the div But im having the exact same problem with this    if you see when i click it doesnt alert "chosen-choices" is the dynamically created class..  in that case i when a user selects and or clicks on that div or box i need to put an alert

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.


There are animals in the matrix. Does this mean that real animals are hooked up to the machine and give it energy and exist in the matrix? Or every time there is an animal seen in the matrix, it's just a program?  I don't think this question is a duplicate of "why there is no animals in the matrix?". Why are there only programmed animals in the Matrix? Why wouldn't they use animals as a source of energy as they use humans?

Aside from the repetitive appearance of the black cat, I can't remember seeing any living animals, either inside the Matrix simulation or in Zion.  How come? Is there an in-universe explanation?


Does using netfilter.ip_conntrack in the kernel in anyway help mitigate (d)DoS attacks or does it make it worse?  I know it adds the ability to track connections and such but just curious if it helps or just makes the attacks worse by bogging down connections.

This is a  about DoS and DDoS mitigation.   I found a massive traffic spike on a website that I host today; I am getting thousands of connections a second and I see I'm using all 100Mbps of my available bandwidth.  Nobody can access my site because all the requests time out, and I can't even log into the server because SSH times out too!  This has happened a couple times before, and each time it's lasted a couple hours and gone away on its own.  Occasionally, my website has another distinct but related problem: my server's load average (which is usually around .25) rockets up to 20 or more and nobody can access my site just the same as the other case.  It also goes away after a few hours.  Restarting my server doesn't help; what can I do to make my site accessible again, and what is happening?  Relatedly, I found once that for a day or two, every time I started my service, it got a connection from a particular IP address and then crashed.  As soon as I started it up again, this happened again and it crashed again.  How is that similar, and what can I do about it?


I've downloaded a patch from some site and trying to apply it (twisted, python web framework).  Several hunks failed.   How do I automate manual patching process using vim?  Details:  I'm trying to automate the process of applying failed hunks.  Many tiny changes, each about adding/removing 1-2 chars. Difficult to see.   I Have to create two new temporary files and :diffthis them manually to see the difference. Yes, outside VCS.  I can imagine a neat way to deal with it using git, but I would prefer to avoid creating git repo for that.

I'm having trouble applying a patch to my source tree, and it's not the usual -p stripping problem. patch is able to find the file to patch.  Specifically, my question is how to read / interpret the .rej files patch creates when it fails on a few hunks. Most discussions of patch/diff I have seen don't include this.


I have the above code and before the insert of try-catch I had this error at logcat     java.lang.NullPointerException: Attempt to invoke interface method   'java.util.Iterator java.util.List.iterator()' on a null object   reference   The problem was into the for loop for the List cellInfoList. Where exactly is the problem.  List<CellInfo> cellInfoList = tm.getAllCellInfo();             try {                 for (final CellInfo info : cellInfoList) {                     if (info instanceof CellInfoLte) {                         final CellSignalStrengthLte lte = ((CellInfoLte) info).getCellSignalStrength();                         final CellIdentityLte identityLte = ((CellInfoLte) info).getCellIdentity();                         test1 = lte.getDbm();                         //lte.getTimingAdvance();                         test2 = identityLte.getMcc();                         //identityLte.getMnc();                         test3 = identityLte.getCi();                     }                 }             } catch (Exception e) {                 Log.e(TAG, "Unable to obtain cell signal information", e);             }   Thank you

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


I've been stuck on some complex Regex writing. I have some textual request - like a SQL request - that I've to transform into a JSON object in Javascript. To do it, I was thinking about making a regex with a pattern which could be repeated n times.   Here is a request example:  INSERT INTO {{ruleName}} RULES {{conditions}} WHEN {{true|false}}  My main problem in here is the conditions part as it can contain a basic condition (object.property {=|!=|<|<=|>|>=} value) or multiple and nested conditions with {AND|OR} or parenthesis (same rule as mathematics).  To catch the first condition, I wrote this regex:/(\s*(\w+.?\w*)\s*(=|!=|>|<|<=|>=)\s*'(.*?)'\s*)/gi  But I cannot manage to write a good regex for the multiple condition or nested condition case.  This is my regex at the moment: /(\s*(\w+.?\w*)\s*(=|!=|>|<|<=|>=)\s*'(.*?)'\s*)((\bAND\b|\bOR\b)(\s*(\w+.?\w*)\s*(=|!=|>|<|<=|>=)\s*'(.*?)'\s*)\s*){0,}/gi  Can anyone help me about it ?  EDIT: As asked, here are two examples of multiple or nested conditions   {condition1} AND {condition2} OR {condition3} multiple conditions here {condition4} AND ({condition5} OR {condition6}) nested conditions there

Is it possible to write a regular expression that matches a nested pattern that occurs an unknown number of times? For example, can a regular expression match an opening and closing brace when there are an unknown number of open/close braces nested within the outer braces?  For example:  public MyMethod() {   if (test)   {     // More { }   }    // More { } } // End   Should match:  {   if (test)   {     // More { }   }    // More { } }


I want to include some figures that are created by tikz package. The figures are in pdf files. Then I convert them to images and include images in other tex files. The reason is that I only need to include part of pdf pages in other files.  I wonder if there is a way to create image directly from latex and tikz codes to save time. Thanks.     Edit by       The user states in a comment that he uses  (a   WYSIWYG LaTeX-based word processor) which apparently does not support   tikz and friends.

I'd like to know how to insert Tikz code in Scientific Workplace tex file. Since SW doesn't support Tikz directly, now I just create Tikz code in another tex editor and export as pdf. Then I convert pdf to images, and import images into SW.


Today someone suggested that my post was a duplicate of another post. I disagreed and dismissed the message by selecting the [No] button below, and clicking the [Submit] button.  This however doesn't dismiss this question. It comes back time and time again when reloading the post.

I have  today and one member was voted as duplicate and private feedback was there, I choose no and submitted the form. When I revisit the question or refresh the page same notice reappears with yes/no options.  In-network tab I got 200 OK status and response as "success":true  Environment: OS: Windows 10 Browser: Chrome 79.0.3945.117 (Official Build) (64-bit)  From the comments, the same issue is happing with   (might be with whole StackExchange network)      From network tab


I've been running into a lot of problems on my Ubuntu 18.04 installation with a package named libidn11. Not having a functioning version of it gets in the way of installing other packages or upgrading installations such as my installation of R. How would I go about fixing this problem without choosing the nuclear option (fresh reinstallation of Ubuntu)?  E: The package libidn11 needs to be reinstalled, but I can't find an archive for it.  Simply trying to reinstall in  doesn't work, and I get the same error message shown above.  EDIT: See @steeldriver's comment  arta@lappy-486:~$ apt policy libidn11 libidn11:   Installed: 1.33-2.1ubuntu1.1   Candidate: 1.33-2.1ubuntu1.1   Version table:  *** 1.33-2.1ubuntu1.1 100         100 /var/lib/dpkg/status      1.33-2.1ubuntu1 500         500 http://archive.ubuntu.com/ubuntu bionic/main amd64 Packages   EDIT 2: Here is the output of sudo apt update:  arta@lappy-486:~$ sudo apt update [sudo] password for arta:  Ign:1 http://dl.google.com/linux/chrome/deb stable InRelease Hit:2 https://repo.nordvpn.com/deb/nordvpn/debian stable InRelease                                                  Get:3 http://dl.google.com/linux/chrome/deb stable Release [943 B]                                                  Hit:4 http://archive.ubuntu.com/ubuntu bionic InRelease                                                                                Ign:5 http://ppa.launchpad.net/kxstudio-team/hydrogen/ubuntu bionic InRelease                                                                 Get:6 http://dl.google.com/linux/chrome/deb stable Release.gpg [819 B]                                                  Err:9 http://ppa.launchpad.net/kxstudio-team/hydrogen/ubuntu bionic Release                                                                     404  Not Found [IP: 91.189.95.83 80] Get:7 http://ppa.launchpad.net/webupd8team/java/ubuntu bionic InRelease [15.4 kB] Hit:8 https://packagecloud.io/slacktechnologies/slack/debian jessie InRelease        E: Repository 'http://dl.google.com/linux/chrome/deb stable Release' changed its 'Origin' value from 'Google, Inc.' to 'Google LLC' N: This must be accepted explicitly before updates for this repository can be applied. See apt-secure(8) manpage for details. Do you want to accept these changes and continue updating from this repository? [y/N] y Get:10 http://dl.google.com/linux/chrome/deb stable/main amd64 Packages [1,103 B] E: Repository 'http://ppa.launchpad.net/webupd8team/java/ubuntu bionic InRelease' changed its 'Label' value from 'Oracle Java (JDK) 8 / 9 Installer PPA' to 'Oracle Java (JDK) 8 Installer PPA (DISCONTINUED)' N: This must be accepted explicitly before updates for this repository can be applied. See apt-secure(8) manpage for details. Do you want to accept these changes and continue updating from this repository? [y/N] y Reading package lists... Done                                                                                E: The repository 'http://ppa.launchpad.net/kxstudio-team/hydrogen/ubuntu bionic Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.

I am looking for the best method to restore /etc/apt/sources.list to default from the command line.  Is there no way to reference the source code of the package which generates this file or something like that? I want a trusted and version-independent way of restoring this file.  Solutions Ruled Out  Before you mark this as a duplicate, note that I have reviewed  already. It is only applicable if you have the Ubuntu GUI available. This question is specific to the command line.  I have also reviewed  where the accepted solution is someone pasted the contents of their sources.list file. This is not an appropriate way to restore the file as the intentions of the person providing the file contents cannot be verified and the file is subject to change with new releases.  I checked out the , but this is also not from Ubuntu so I do not plan to use it.


Let $G$ be a group and $H$, a proper subgroup of $G$ with $[G:H]<\infty$. Is it  right that $\bigcup\limits_{g\in G}gHg^{-1}$ is a proper subset of $G $? If $G$ is a finite group we can prove this claim, but is this right for infinite groups?

Let G be a finite group and H be a proper subgroup. Prove that the union of the conjugates of H is not the whole of G.  Thanks for any help


* I did an update on my Macbook Retina 13" to the most recent version of Sierra OS X. The computer never gets past the Apple logo (black screen with a full progress bar). *  This is a copy of the problem previously written up in November.  None of the solutions worked nor a few others.

I did an update on my Macbook Retina 13" to the most recent version of Sierra OS X. The computer never gets past the Apple logo (black screen with a full progress bar).   I booted into Verbose Mode (command + v) and see that it is stuck at the following point:  SmartBattery: finished polling type 4  Every now and then it will add another line of text (same text) but it never moves beyond that point.  Any advice please! It is a real pain to keep restoring from my Time Machine backup!


Let $A$ be a finely generated Abelian group. Prove that there is a topological space $X$ with a basic point $x_0$ such that $\pi_1(X,x_0)\cong A$.  I'm trying to solve this problem but I do not know where to start, here are several posts similar to this that I do not understand:     Is there an easy way to prove my proposition? Thank you very much

I am studying elementary Algebraic Topology recently. I have seen that a topological space is identified with a group. We are telling the group as Fundamental Group. So every topological space $X$ and for any $x \epsilon X$ there is a fundamental group $\pi_1 (X,x)$. I have a question about the converse. If we consider any arbitrary group $G$, then does there exist a topological space $X$ and an element $x\epsilon X$ such that $\pi_1 (X,x)=G$?


I have a simple 404 redirect in my .htaccess file:  ErrorDocument 401 /404.htm  ErrorDocument 404 /404.htm  RewriteEngine On  RewriteCond %{SERVER_PORT} 80  RewriteRule ^(.*)$ https://hypnosis-retreat.co.uk/$1 [R,L]   When I enter the domain https://example.co.uk/bhabha it correctly renders the 404 page. Where I enter the URL https://example.co.uk/bhabha/morebhabha it fails to render the 404 page correctly.  I need to trap a path that goes nowhere.

I am trying to make my url from this:  example.com/view.php?id=15   To this:  example.com/watch/15   My code in .htaccess is as follows:  Options -Indexes Options +FollowSymlinks RewriteEngine On RewriteRule ^watch/([^/]+) view.php?id=$1 [NC]   Now if I go to example.com/watch/15 it loads the content but without any JS, CSS because in this case it looks for CSS and JS under the /watch folder which doesn't exist.  How do I make this option work properly? I don't want to create watch folder and copy-paste CSS and JS so it will embed properly.


I assume this is a big no-go for user experience but I wasn't able to find a question covering this (common) issue.  We are rewriting our desktop GUI and we have to deal with lots of settings / form fields. Some of them include units and I wonder if there is a best practice for dealing with units and labeling them. Right now we put it like this:    What would you recommend doing instead?

Do you have experience implementing text inputs or drop-downs in-line with other text or forms? Is this approach any better than just creating a separate field/label?  In the example below the user has the option to indicate when to be reminded again (in one, two, or three days). When they are reminded of an assignment, they simply get an email or text message.


This may be a stupid question in the sense that it is obvious to everyone who has done it once - but I haven't.  So, I know that adb backup -f myAndroidBackup.ab com.corp.app can back up a single app's data without root. Will restoring this backup with adb touch only com.corp.app, or will it wipe other apps first?

ICS devices support creating backups using adb backup, and restoring them using adb restore. Using adb backup, one can select that everything should be backed up, or only a certain package.  However, adb restore lacks all the options of adb backup. When I call adb restore backup.ab, where backup.ab is only the backup of a single package, the phone shows me a warning dialog saying that all settings are going to be lost after restoring the backup. Is it true that restoring a single package backup wipes all data on the phone? If yes, is it somehow possible to restore a single package using adb restore?


I am trying to take the href attribute from an a tag, and apply that as the background-image of the anchor tag's child. For some reason it is not working. I have the following html:

   and the following javascript(using jquery):    $('figure').each( function() {     var thumb = $(this).find('.thumbnail');     var image = $(this).find('a').attr('href');     $(thumb).css('background-image', image);   });

I have an image URL in a imageUrl variable and I am trying to set it as CSS style, using jQuery:  $('myObject').css('background-image', imageUrl);   This seems to be not working, as:  console.log($('myObject').css('background-image'));   returns none.  Any idea, what I am doing wrong?


I was practicing English online and a guy created a room and wrote "No Indian, Pakistani and Bangladeshi accent." He was an Indian himself and I said: "I'm not offended being from the subcontinent but some people even from other countries might get/be offended." He got a little offended and told me to leave and I said: "Please don't be/get offended. I'm just saying." Question- Please let me know the difference between 'be offended' and 'get offended.'

I was used to working long hours. I got used to working long hours.  What meaning do the verbs be and get have here? My textbook doesn't explain it. But from the examples they're used in, I have an impression that get emphasizes that there is some transition between one state and another. For example in my sentence got used means that I was not used to it before but then became used to it. While was used doesn't imply that, maybe I was always used to it. And this usage in Present Simple:  I am used to it. I get used to it.  Does get imply that however I am not used to it at the moment but I will be used to it soon?


I have tried to delete all of the music off through iTunes and through settings. the computer and settings says it is gone but when i go to the music app it is all still there just not downloaded. all of my songs are shown but they have the cloud icon with the arrow pointing down next to them. I went them all gone to the point that I can't even see them on my phone. How do i do this?

I have an iPhone 4s with iOS7 and somehow I see iCloud music which I haven't downloaded yet on my iOS device. How can I get rid of these, I do not need to see them.


I have come across at a proof in the book (I'm not writing it all down) but at the last lines it says: $9(73+8)^n + (73-9)8^n$ Is congruent to $9x8^n - 9x8^n$ is congruent to 0 (mod 73). What i don't get is that how is $9(73+8)^n + (73-9)8^n$ when divided by 73 leaves the remainder $9x8^n - 9x8^n$ Or zero? I mean the value of n can be any and its binomial expansion can be bigger so how to know its really divisble by 73. Is there any simpler expression of above line so that i can understand it clearly. Or with other similar example which can be helpful to understand the concept. Thanks

I have seen other criteria for divisibility by 7. Criterion described below present in the book Handbook of Mathematics for IN Bronshtein (p. 323) is interesting, but could not prove it. Let $n = (a_ka_{k-1}\ldots a_2a_1a_0)_{10} = \displaystyle{\sum_{j=0}^{k}}a_{k-j}10^{k-j}$. The expression $$ Q_{3}^{\prime}(n) = (a_2a_1a_0)_{10} - (a_5a_4a_3)_{10} + (a_8a_7a_6)_{10} -\ldots  $$ are called alternating sum of the digits of third order of $n$. For example,  $$ Q_{3}^{\prime}(123456789) = 789-456+123=456 $$ Proposition: $7 | n \ \Leftrightarrow \ 7 | Q_{3}^{\prime}(n)$.  proof. ??  Thanks for any help.


I'm trying to draw a bar diagram with 4 value groups each consisting of 5 bars. I think it's a scaling problem, so not all the groups were drawn. I already had a look at the documentation but I couldn't find the right config to make that happen...  \documentclass[tikz, border=10pt]{standalone}  \usepackage{pgfplots}  \pgfplotsset{compat=1.16, x tick label style={font=\tiny,align=center}, y tick label style={font=\tiny},% }  \begin{document} \begin{tikzpicture} \begin{axis}[% ybar,% enlargelimits=0.05,% title={title},% symbolic x coords={a,b,c,d},% xtick={data},% ylabel={y-label},% xlabel={},% xticklabels={ValueGroup 1,ValueGroup 2,ValueGroup 3,ValueGroup 4}, legend style={at={(0.5,-0.15)}, anchor=north,legend columns=-1}, ybar interval=0.7, ]  \addplot coordinates{(a,34) (b,36) (c,70) (d,65)}; \addplot coordinates{(a,45) (b,45) (c,43) (d,43)}; \addplot coordinates{(a,23) (b,32) (c,22) (d,20)}; \addplot coordinates{(a,76) (b,25) (c,35) (d,25)}; \addplot coordinates{(a,22) (b,12) (c,45) (d,34)};  \legend{\tiny{bar 1},\tiny{bar 2},\tiny{bar 3},\tiny{bar 4},\tiny{bar 5}} \end{axis}  \end{tikzpicture} \end{document}


I recently made the stupid mistake of uninstalling python3.6 because I upgraded to python 3.9, not knowing how important python is for Ubuntu. I got signed out automatically and when I tried to sign in it said something like "Start of session failed" (it could have been something slightly different, I don't remember exactly), so I rebooted my computer and then, instead of showing my username, a text console was shown. I asked about it in another question and they told me that the easiest solution is to back up my files and completely reinstall everything. However, I don't know how to get out of the text console, Ctrl+Alt+F7 doesn't work and neither does "Login as root" Also, I don't know how to recover my files, I plugged in a flash drive and nothing happened.

I am a new Ubuntu user running Ubuntu 13.04.  I've been trying to install and use a DeDRM tool, but I've been having problems doing so. I was following some directions that said I needed a version of Python 2.7, but not anything Python 3.0 or later (because 3.0 versions are missing some necessary libraries?). I tried to install Python 2.7.5.6, but it didn't work. I thought it was probably because I had the later version of Python, so I went through terminal and removed Python 3.3, so I could install the earlier version of Python.  Now that I've uninstalled Python 3.3, a lot of applications no longer work, including the terminal and the Ubuntu Software Center. I have no idea how to fix this problem now.


Looking for some input experience here. I have a Nikon D3300 and the following lenses:  18-55 VR kit 55-200 VR 18-200 VR 35mm fixed  I primarily use the 18-200 lens out of convenience but was doing some comparison shots today and noticed something that I wasn't expecting. What I was trying to do is take a pictures with each lens where the focal points intersect and compare results / settings / etc. Usual observations and pro's con's that have been discussed many times between the lenses but one observation surprised me and I wanted to know if this is right and others observe the same.  At 200mm, the 55-200 has a noticeable smaller FOV or higher zoom compared the the 18-200 at 200mm.  I always assumed that 200mm was 200mm but that is not what I observed. Does this result make sense and have others experienced the same? TL;DR - Observed 55-200 @ 200 smaller FOV / higher zoom than 18-200 @ 200. Does this make sense?

I've been testing out a Nikon 18-200mm F3.5-5.6 against a Nikon 55-300mm F4.5-5.6   I took two pictures of a door knob from an equal distance of about 3 meters away with the same Nikon d7100 DX camera but each with the different lenses both set to the same focal length of 200mm.   To my surprise, the image taken with the 55-300mm lens gave a considerably tighter crop than the one taken with the 18-200.   Is this normal, and if so how is this possible? I was under the impression that the field of view should be the same if both lenses are set to the same focal length. I'm asking this question because I bought the 18-200mm lens second hand and I'm worried there is something wrong with it even though it does appear to be fine.   Here are the example photos. Note the meta data on the images do confirm both were taken at 200mm. I was not using a tripod, so there was probably a slight discrepancy, but I did make sure to sit in the exact same position and leaning back against a wall in the same spot to take the photos. The difference in crop was immediately apparent


I tried to set Alt+Shift as the keys to switching a keyboard layout in my Ubuntu 13.10.  The only problem is every time I type Alt+Shift when I set the keys, it is also writing "Next Group".  When I try to switch layouts, it doesn't work. What is this "Next Group" key and what I did wrong?    I also tried:  setxkbmap -option grp:alt_shift_toggle en,he   but I got this error:  Error loading new keyboard description   My question is what is this "Next Group" key and why is it showing when I don't press any other key, and not how to use shift_alt to change keyboard layout.

I recently upgraded to Ubuntu 13.10, with the new keyboard handling system. The little "switch keyboard" option does not let me set it to Alt+Shift. How can I get this keyboard binding, as I have absolutely no interest in using the Mac-esque Super+Space combo?


Does software like Dr. Fone, MiniTool that required "root" on android really work 100% for recovering my lost photo?  First of all my phone is not rooted.  I've lost my important photo (deleted permanently) which I kept in internal storage. And recently i always keep my phone clean that is always using cleaner app like CCleaner for cleaning my DCIM folder, thumbnails, and cache. And i've tried a lot of app like DiskDigger and another app in playstore for recover my photo, but they didn't work.  And my last hope is rooting my phone and use software like Dr. Fone, or MiniTool. (If these gonna work)  And i'm really really searching the accurated answer here which will advise me for rooting my phone or not. Because as you know, rooting is very dangerous cz i have bad experience with rooting. I mean if there is no way to recovery my data so i oughtn't to root my phone.  Please help me. Thanks in advance!

I factory reset my rooted Android M phone but now I realize that there was a file in the /data directory which I need.  Is it possible to create an image (.img or something similar) of the /data partition so that I could run some recovery software for ext4 on that image? I have a little knowledge about ADB.


i have a string "8120, 8120NGE, 8120NG, 8130, 8130NG, 8130NGE".  And i have a char* (0x0012d094 "8130")  I want to see if the "8130" is in. That exact word.  So i am using     istringstream iss(boards);   string token;   AVBOOL foundBool=FALSE;   while(std::getline(iss, token, ','))   {     const char * compareToken = token.c_str();       token.compare(board);     // with that : it doesn't work cause "8130" is not    equal   0x0012d094 "8130"     if(strcmp(compareToken,board)==0) //with that it doesnt work cause 0x0012cef0 " 8130" is not equal 0x0012d094 "8130"       {         foundBool=TRUE;       }   }   So the question is how do i compare a string with a char * .  Do I need to convert the char into a string and then use string.compare OR  Do i need to convert the string into a char and use strcmp? OR Do i need to do something else?  I am kind of lost here.

What is the preferred way to remove spaces from a string in C++? I could loop through all the characters and build a new string, but is there a better way?


I have this table:  Name    Address                  Code James   CT                       Homeaddress Mark    mark@goole.com           Email John    John@hotmail.com         homeemail ...   This is what I want:   Name        Homeaddress      Email           homeemail james       CT mark                         mark@google.com john                                         John@hotmail.com   I am creating a view and dont have privilages to alter the base tables. I was thinking maybe an IF statement might help

I have a SQL Server instance that has a linked server to an Oracle server. There is a table on the Oracle server called PersonOptions which contains the following data:  ╔══════════╦══════════╗ ║ PersonID ║ OptionID ║ ╠══════════╬══════════╣ ║        1 ║ A        ║ ║        1 ║ B        ║ ║        2 ║ C        ║ ║        3 ║ B        ║ ║        4 ║ A        ║ ║        4 ║ C        ║ ╚══════════╩══════════╝   I need to pivot that data so the results are:  ╔══════════╦═════════╦══════════╦══════════╗ ║ PersonID ║ OptionA ║ Option B ║ Option C ║ ╠══════════╬═════════╬══════════╬══════════╣ ║        1 ║       1 ║        1 ║          ║ ║        2 ║         ║          ║        1 ║ ║        3 ║         ║        1 ║          ║ ║        4 ║       1 ║          ║        1 ║ ╚══════════╩═════════╩══════════╩══════════╝   Any suggestions?


I've been using the original Java Edition on my old Windows 7 PC for years and my family just gave me a new Windows 10 PC for Christmas. Can I keep using my old Java Edition on the new machine or do I have to switch to the Windows 10 Edition of Minecraft? I really don't want to switch...

I have Minecraft PC on my computer, which is on Windows 7. We are upgrading to Windows 10.  My question is, can I play my current version on Windows 10, or must I play the Windows 10 Pocket Edition Style gameplay? If I must have the Windows 10 edition, do I have to buy it, or will it be free since I bought regular Minecraft?


When a user votes to close their own question as a duplicate, it is treated like any regular vote to close, auto-adding a comment to the page suggesting the possible duplicate.    Upon refreshing the page, the user is prompted to re-confirm that yes, their question is a duplicate.    "This question may already have an answer here" - You don't say? :P  Users can already decide to close their own question as a duplicate. It only takes a single extra step to confirm the closure.  When a user votes to close their own question as a duplicate, shouldn't the question be closed instantly without needing to refresh and reconfirm?

Someone voted to close my question as a duplicate. I agreed, so I cast my close vote (I have enough reputation to vote to close).  . So I expected this to happen.  But it didn't. This confused me — is this not a question I asked after all? No, it is. Maybe I need to reload the page? Nope, the question still isn't closed. Is the asker confirmation feature broken? Well, there's the “This question may already have an answer here” banner at the top. What if I click “That solved my problem!”? Ah, that does close the question.  It turns out that only clicking “That solved my problem!” instantly closes the question. Casting a close vote has a different effect, it's just an ordinary close vote.  Please make casting a close vote equivalent to clicking “That solved my problem!”.


Twice now I've seen questions on Stack Overflow where one of my company's products might provide an answer to the question.  One was a slightly vague connection about object-relational mapping, but the other was a specific question about workshop/event management where we have a product which is almost an exact match for the questioner's needs.  Of course the questioner should take a pinch of salt with anything I say about it, but it might be useful to have the product brought to his attention as one possible solution.  What are the rules and guidelines about answering with something I worked on?

I would like to help my fellow Stackizens, using material from my blog or other website.  But external links are sometimes viewed as excessive promotion.  From the FAQ:     Be careful, because the community   frowns on overt self-promotion and   tends to vote it down and flag it as   spam. Post good, relevant answers, and   if they happen to be about your   product or website, so be it. However,   you must disclose your affiliation in   your answers. Also, if a huge   percentage of your posts include a   mention of your product or website,   you're probably here for the wrong   reasons.   I have tried posting answers that reference my blog, and I have followed the above rules, but my answers still get flagged as spam.  How can I craft an answer that references my blog, website or other resource, but is still acceptable to the community?


I saw closure being declared using function expression and not function declaration. Being new to java script i have below queries. i tried referring similar question but it didn't helped me.   Do closure always need to be declared using function expression and not function definition Do closure need to be self invoked in function expression I understand key difference between Function declaration and function expression id hoisting. can anyone help me when and which in situation i should decide whether i should go with function declaration or function expression. what are the other advantages and disadvantages of using any one of them   Sorry some questions might be answered previously or kind of basic but being new to it i feel its confusing  below is the example i have done using function declaration but its not giving me proper result    function counter() { var count = 0;  return function() { return count++; } } <!-- using function declaration -->  <button onclick="alert(counter())">Counter</button>       var counter = (function() {   var count = 0;  return function() { return count++; }   increment(); })(); <button onclick="alert(counter())">Counter</button>

How would you explain JavaScript closures to someone with a knowledge of the concepts they consist of (for example functions, variables and the like), but does not understand closures themselves?  I have seen  given on Wikipedia, but unfortunately it did not help.


Does a foe declare its intent to make an attack of opportunity when a creature declares its intent to provoke attacks of opportunity by moving within the foe's threatened area, into the foe's space, or exiting the foe's threatened area?  That is, is an Acrobatics skill check made in response to a creature's intent to make an attack of opportunity or does the creature make an Acrobatics skill check first to negate the possibility of the foe making the attack of opportunity?  Similarly, can a foe "take back" its declared but unmade attack of opportunity if it "wastes" its attack of opportunity against a creature that would have provoked an attack of opportunity but doesn't provoke an attack of opportunity because the creature made an Acrobatics skill check?

I think I would need at least 2.  One for moving past the enemies occupied square and another for the threatened square, but do I need an acrobatics check for every threatened square I move past or just one check for all of them?  For example;  At the start of my turn I (a medium sized creature) am not in any threatened squares.  I want to move past a medium sized creature with 5 ft reach right in front of me completely and in a straight line.  That means I would need to move through 1 threatened square, then his occupied square, then another threatened square to clear my way to the other side into an square that isn't threatened.  How many checks would I need? 2 or 3?  Also, if 2 enemies are threatening the same square the table states that I simply increase the check by 2, but what if they have different CMD?  Do I take the highest one and increase it by 2?


Let (X,d) a metric space. Show that the function y↦d(x,y) is continuous. Please help me, I don't know where to start.

Let $(X, d)$ be a metric space. Is the function $x\mapsto d(x, z)$ continuous? Is it uniformly continuous?


I'm a beginner in electronics world, I've developed things before but not so sofisticated. Now I have to create a prototype and I need to measure voltages up to 120V. I've seen there are sensors that can do this job but they're only capable to measure 5-25V. Is there any way I can transform voltage from 5-120V to 5-25? I need to know when there's a change in voltage. Or any other idea that could help me? I explain: my controller will have storaged the voltage when there's a device plugged-in and it's working, I need to find the way to measure this voltage so I'll be able to storage it dynamicly and compare this storaged value to the actual so I'll know when the device plugged-in is ON or OFF. I appreciate your attention, thanks.

I'm a Electrical Engineering student and I want to sense and sample the voltage signal  coming from a wall socket (110V - 220V). I came up with the following circuit using a voltage divider with high impedance and a diferential amplifier. I would like to avoid using a transformer because of weight constraints.  Is there a better way to solve this problem? Should I use a capacitor divider instead?


In Python I want to find the maximum value out of dictionary which has the duplicates, for example :  my_dict = {1: 0, 12: 2, 36: 2, 24: 2, 33: 2, 4: 1}   and the maximum value is 2.  And I want to find the maximum key of the maximum value which is 36:2 in this example.

I have a dictionary: keys are strings, values are integers.  Example:   stats = {'a':1000, 'b':3000, 'c': 100}   I'd like to get 'b' as an answer, since it's the key with a higher value.  I did the following, using an intermediate list with reversed key-value tuples:  inverse = [(value, key) for key, value in stats.items()] print max(inverse)[1]   Is that one the better (or even more elegant) approach?


The context is  "The mercenaries lie/lay dead." "The animal lies/lays dead."  It's present tense and there's a corpse involved. I've looked it up elsewhere and I just don't understand the rules. Something about an object? Is a corpse an object?

How do I know when to use lay and when to use lie, and what are the different forms of each verb? I'm always getting them confused.


Trying to do the following:  let obj = {     user: 'john',     foo: 'bar',     someKey,     ...KeyParse.explode(model.key) // returns an object };   Is there any way to do the above? ie. spread the object returned from KeyParse.explode() into obj? So all the KeyParse.explode() keys would be populated into obj...

I need to be able to merge two (very simple) JavaScript objects at runtime.  For example I'd like to:  var obj1 = { food: 'pizza', car: 'ford' } var obj2 = { animal: 'dog' }  obj1.merge(obj2);  //obj1 now has three properties: food, car, and animal   Does anyone have a script for this or know of a built in way to do this?  I do not need recursion, and I do not need to merge functions, just methods on flat objects.


Is this T or F? and most importantly, why?  I'll be using any answers for a basis or completely my other questions, since my understanding  is still a little poor.

I am trying to prove:     $a\mid b \land b\mid c \Rightarrow a\mid c $   $a\mid b$ means that a divides b if there is an integer k, that $b=k\cdot a$  Please give me a hint on how to start, because I have no idea.


For example, I just saw this phrase on social media:  The way 2020 going, I ain't buyin' no PS5.  I mean, in this instance, I can ultimately see that what the poster actually mean is that "I ain't buyin' any PS5". But I actually saw many instances of phrases like this in the past that's a lot harder to decipher whether the poster actually meant the phrase to be a positive or negative.

In my native language, double negations "cancel out". I have been trying to learn English using movies and such things, but double negation confuses me. I see instances when double negation cancels out, and some when they do not.  For example, "I haven't got no money" is interpreted as "I have no money." "There wasn't anyone who didn't enjoy the party" is interpreted as "Everyone enjoyed the party."  Is this context dependent? If so, how does one decide which interpretation is correct?


I want to check if a file exists, and if it doesn't exists, I want to ask the user if they'd like to create it. Whether the user inputs Y or N, only "Whatever you say" appears on the screen.   #!/bin/bash  #This is testing if a file (myFile) exists  if [ -f ~/myFile  ] then          echo "The file exists!" else         echo "The file does not exist. Would you like to create it? (Y/N)"         read ANSWER fi  if [ "$ANSWER"="N" ] then         echo "Whatever you say!" else         touch myFile         echo "The file has been created!" fi

I am using the below script to move two days back when script runs at starting two days of the year and also check first and second days of every month and move two days back. if [$month="01"] && [$day="01"]; then         date="$last_month/$yes_day/$last_year"         fulldate="$last_month/$yes_day/$last_year" else         if [$month="01"] && [$day="02"]; then                 date="$last_month/$yes_day/$last_year"                 fulldate="$last_month/$yes_day/$last_year"         else                 if [ $day = "01" ]; then                         date="$last_month/$yes_day/$year"                         fulldate="$year$last_month$yes_day"                 else                         if [ $day = "02" ]; then                                 date="$last_month/$yes_day/$year"                                 fulldate="$year$last_month$yes_day"                         else                                 date="$month/$yes_day/$year"                                 fulldate="$year$month$yes_day"                         fi                 fi         fi fi  But my bad am getting the below error message Etime_script.sh: line 19: [06=01]: command not found Etime_script.sh: line 24: [06=01]: command not found


While looking at a tutorial on the Anisotropic shader I got stuck. The controls it tells me to use are nowhere to be found.   One of the first things is tells me to do is to add an hdr file for some lighting. In the video when he has the World tab selected there is an option called Surface and within that there is a Color option but it's not there, and also isn't there for materials!  Did these things move to a hidden location between 2.65 (when the tutorial was written) and 2.74? Might I be in some mode that causes that option to be missing?   This is the tutorial I got stuck on:   Any pointers to good resources for beginners would be great as would any ideas on what stupid mistake I'm making. I didn't bother making the sauce pan in the tutorial instead just going with the cube you get by default but I don't think that would cause this issue.

Complete beginner here.  I'm trying to follow  tutorial on Anisotropic shaders, but my property panel looks nothing like the property panel in the tutorial.  For example, when creating a material, this is what his property panel looks like:    But this is what mine looks like, if I follow the same path:    I'm sure I'm missing something obvious.  How can I see the property panel shown in the tutorial?


Blender is being used by Openshot and by default Blender uses Bfont to create text objects.   Currently Bfont that my system has from the 2.79 lacks russian characters. So the only way to render russian text is to load a different font, which I can't do as Openshot uses Bfont in most of Blender interactions without my intervention uses blender -b.   So question is:  how can I make sure that when blender is started it uses (as Bfont, default font to render text objects another font of my choice) and this is loaded upon startup.    I know how to do it by modifying source files and recompiling blender and openshot from scratch.  I can put another font for blender as bfont and recompile.  I can also edit python scripts on openshot side and try to use/load another font, prior to calling blender.  However, I wanted to achieve the same with vanilla blender (those that I download from blender website)  So any way to call as Bfont some other fine via  config option (User prefs) or placing a file in some ~/.blender/... directory?

I have been playing with the settings for the text object recently, and every time I add a new text object, I need to change the font to my favorite one. (Eurostile LT ExtendedTwo) Is there any way to change the default font so I do not need to change it every time I add a new text object?   Example:


There is a website called CodeFights, and they have a challenge which has caused me a little bit of a problem.  Here is my code:  boolean checkPalindrome(String inputString) { String[] inputStringArray = inputString.split("");      String reverseInputString = "";      for (int x = inputString.length() - 1; x >= 0; x = x - 1) {         reverseInputString = reverseInputString + inputStringArray[x];     }      System.out.println(reverseInputString); // for debugging purposes only      System.out.println(inputString); // for debugging purposes only       if (reverseInputString == inputString) {         return true;     } else {         return false;     } }   The weird stuff:   Let's say that inputString equals aba. Then System.out.println(reverseInputString); and System.out.println(inputString); are both going to print out aba, which is just what I want. However, my if statement is going to return false, and I don't have a single clue why it is always happening.   I mean literally, I've tried everything in my knowledge to debug my humble "application", but nada; it doesn't seem to show any sign of working properly. It might very well be that the solution is quite easy, in which case I apologise for even asking this question, however, I've only been learning Java for 3 days, which is not a long period of time.  I am looking forward to reading your ideas and opinion on this matter.  Thank you for your help :)

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 want to change operating systems from Windows XP to Ubuntu.   System Info • Microsoft Windows XP Professional 2002 Service Pack 3 • Pentium 4 CPU 2.80GHz • 5GB RAM    What is the best version of Ubuntu to install on my computer?

For a given hardware configuration, how do I find out if Ubuntu will run on it? What considerations should I take into account when choosing an Ubuntu version and  such as:    with a lighter desktop than the usual Gnome and Unity  with the even lighter LXDE desktop   Obviously Ubuntu does not run on some processor architectures. So how do I go about choosing the right version and derivate. How can I find out the minmal system requirements?


How can one prove that the random sample is normally distributed if the sample mean and sample variance are independent?

I was wondering if there are any distributions besides the normal where the mean and variance are independent of each other (or in other words, where the variance is not a function of the mean).


Imagine you have a button like this:  <input name="myButton" type="button" value="button" onclick="return test();" >   where the test functions is as follows:  function test(){   // do something   return true; // based on some logic return boolean }   Now let's say,I don't know what is set for the onclick event, and at runtime I need to read the function or any code set to onclick and run it. Here is an example:  var btn = getElementById('myButton'); var btnOnClickFunc = btn.onclick; if (btnOnClickFunc) {     // do something }   I know this doesn't work, and that's actually my question. How can I read the button's onclick event in this example at runtime?  An example of this case is when the onclick is attached to the button later using jQuery.

I have a page where some event listeners are attached to input boxes and select boxes. Is there a way to find out which event listeners are observing a particular DOM node and for what event?  Events are attached using:    Event.observe; DOM's addEventListener; As element attribute element.onclick.


I'm using both Windows 7 and XP (simulatnateously on two machines) and I'm getting frustrated with the fact that both versions use different keystrokes to move up the folder hierarchy in explorer.  Windows 7 uses [Alt+Up] and XP uses [Backspace].  I've had a look around and tried  but as it says:  Things that SharpKeys will not do:   Map multiple key presses to one key - e.g. it will not support an attempt to remap Ctrl+C to the F5 key    So, is there any solution?  TIA, Paolo

I just bought an IBM Model M keyboard. While awesome, it lacks a windows key and multimedia keys. While there are many programs out there that can map one key to another, or one key to a key sequence, are there any programs that will map a keyboard sequence to a single key?  Edit: OS = Win7


I have a weird problem with my ASUS K556UB laptop. When I start the computer, the touchpad doesn't work, it is shown in xinput output and in /proc/bus/input/devices.   Here's the weird part: it starts working when I wake the computer from suspend. So the driver is working. Anyone got any idea how I could get it working without suspending and waking? Here are the outputs from xinput, cat /proc/bus/input/devices and synclient, respectively:        As you can see, it's an Elantech touchpad, I've had a few laptops with Elantech touchpads and they worked perfectly. A mouse is also in the outputs, I had to attach it to use the computer. It had no effect on the touchpad.  Hardware: Asus laptop K556UB OS: Ubuntu 16.04 64 bit

So I have and Asus R558UF notebook with an Elantech Touchpad. After installing Ubuntu 16.04, the touchpad worked once but after restarting, it failed to work and has not been working ever since.  This is output of xinput:   ↳ Elan Touchpad                            id=12   [slave  pointer  (2)]   In Mouse and Touchpad settings, the touchpad is enabled. What should I do to fix this?


I'm trying to figure out how to change which version of PHP the php alias uses...  I want it to use: /opt/plesk/php/5.6/bin/php  But it currently uses: /usr/bin/php (I think)  How can I ensure that when typing php through SSH, that it's using the updated plesk version?

Our hosting providers have installed 3 versions of PHP onto our linux box and when I SSH into it the command php points to use/bin/php which is version 5.2, the command php-5.4 points to usr/bin/php-5.4 which is version 5.4 of course.   This isn't a problem when I just need to run a single script that needs a newer version of php, I can just specify php-5.4, however when I try to run the Laravel installer or try to install Laravel using Composer it is throwing errors that are caused by php 5.2 being used.  Is there a way to change where the php keyword points? Or do I need to remove bin/php and rename bin/php-5.4?


How can I explain to someone who is a beginner, the basic idea and intuition behind dy/dx? I'm introducing calculus to one of my friends and here are the questions I might encounter: Why dy/dx? What do I even need to find the slope? How does that relate to rate of change of y with respect to x? What could be some real life examples for a better understanding? What information does the slope at every point of a curve, which is just a line, give me?  I'd like to explain all of this giving an intuitive sense to the formal differential calculus. Thanks!

In the book Thomas's Calculus (11th edition) it is mentioned (Section 3.8 pg 225) that the derivative $dy/dx$ is not a ratio. Couldn't it be interpreted as a ratio, because according to the formula $dy = f'(x)dx$ we are able to plug in values for $dx$ and calculate a $dy$ (differential). Then if we rearrange we get $dy/dx$ which could be seen as a ratio.   I wonder if the author says this because $dx$ is an independent variable, and $dy$ is a dependent variable, for $dy/dx$ to be a ratio both variables need to be independent.. maybe?


I installed Lubuntu and created 3 partitions:   1 swap 1 Lubuntu 1 Windows   I turned my laptop on and I got the boot menu and I looked for Windows 7, but there's just Lubuntu.  The device is a Toshiba Satellite c855-s5203 with 2 GB RAM.  I have checked in the drive application and Windows does not show up.  How can I fix this?

I installed Windows on my computer, followed by an installation of Ubuntu. However, now I'm unable to boot into my Windows install.  What can I do to fix this?


Professor required his students to return their papers typed.      vs        Professor required that his students return their papers typed.      Which of the examples is correct? Do they have the same meaning? What is the preferred usage?   and  do not mention any usage differences

Isn't kindness already implied when you say "I request you to..."?  When I say "I humbly request you to...", the word humbly helps me to label the state of my behavior during the request.  On the other hand, what value does the word kindly add to the request?


I want my docs en pics in the cloud but also a backup. Want to backup to a TimeCapsule with TimeMachine (or if necessairy an other softwareprogram). Wonder if that’s possible.

Does TimeMachine backup the files I have in iCloud Drive? I want to use iCloud Drive more for files I don't use a lot. But it is important that there is a regular backup.


There are some MacBook Pros for example from 2013 which have an NVIDIA graphics card built in by Apple and they are supported under macOS Mojave or Catalina. But if you upgrade one of those models to Catilina, will you lose your NVIDIA graphics and be stuck with the Intel Iris one or does this only apply to eGPUs, user-upgraded GPUs and with Hackintoshs? To my mind, just losing your NVIDIA graphics is rather unlikely as Apple does not have any warnings regarding this on their website, but I am asking here so I can be completely certain.

I own an early 2013 15'' MacBook Pro (MacBookPro10,1), and I've been running every macOS update till Mojave, included. The mac has two GPUs, which get selected automatically depending on the running apps:   Intel HD Graphics 4000 (integrated) NVIDIA GeForce GT 650M (discrete)   Recently I've been reading about the fact that macOS Mojave has dropped any support for Nvidia GPUs, and digging further I've found out that users have been reporting issues with my model specifically. Apparently, since High Sierra there have been issues with the GeForce GT 650M and macOS, with GUI slow downs and crashes. I've found plenty of posts of people complaining about the lack of support and drivers from Apple.  Personally I have not observed any of these issues, but now I wonder. I know for sure that I've been using the discrete GPU often (I track my energy usage), but maybe I've just not noticed the slowdowns.  I've inspected the version of the Nvidia drivers (system report > software > extensions), and it says:  GeForce:    Version:          12.0.24   Last Modified:    12/10/2018, 05:10   Bundle ID:        com.apple.GeForce   Notarised:        Yes   Loaded:           Yes   Get Info String:  GeForce 12.0.24 355.11.10.50.10.103   Obtained from:    Apple   Kind:             Intel   Architectures:    x86_64   64-Bit (Intel):   Yes   Location:         /System/Library/Extensions/GeForce.kext   Kext Version:     12.0.0   Load Address:     18446743521870100000   Loadable:         Yes   Dependencies:     Satisfied   Signed by:        Software Signing, Apple Code Signing Certification Authority, Apple Root CA   They seem to have been updated one year ago (with Mojave?), but that doesn't fit with what I've been reading about the total lack of support.  Does anyone know what's the current state of the game for my MacBook Pro model?


Are we allowed to embed full length copyrighted pirated movies on Stack Exchange? If not, what should someone do if they see this happen? I flagged a post that had one but it was declined.      answered 7 hours ago by Richard      Piracy/Copyright infringement. Full movie posted. – cde 4 hours ago   declined - flags should only be used to make moderators aware of content that requires their intervention   I know SE takes copyright infringement very serious, as the standard policy is to ban someone for tag edits that include Wikipedia text, but are pirated movies exempt?

I recently came across a question asking how   Included is both links to torrent sites, and direct links to "torrent download pages" for copyrighted content.  I took the liberty of turning them into non-links. So people wanting to answer the question could see the link structure, without SO actually linking to the pages in question.  The OP has since gone in and reinstated the links.  I feel I was correct, doing my bit to help clean up SO. I'm not a mod, so I can't enforce anything, and I don't want to start some sort of ping-pong editing battle removing these links just to have him put them back.  So what's the policy on links to links to pirate content? Should I be flagging this post for mod attention?


Can someone help me with this integral? I can't even think of where to begin.  $$\int_0^\infty \frac{|\sin (2x)| - | \sin (3x) |}x dx$$  Thanks!

How can I prove the Theorem of Frullani? I did not even know all the hypothesis that $f$ must satisfy, but I think that this are  Let $\,f:\left[ {0,\infty } \right) \to \mathbb R$ be a a continuously differentiable function such that $$ \mathop {\lim }\limits_{x \to \infty } f\left( x \right) = 0, $$ and let $ a,b \in \left( {0,\infty } \right)$. Prove that $$ \int\limits_0^{\infty}  {\frac{{f\left( {ax} \right) - f\left( {bx} \right)}} {x}}dx  = f\left( 0 \right)\left[ {\ln \frac{b} {a}} \right] $$  If you know a more general version please give it to me )= I can´t prove it.


I am using the following formula in a column of cells: `=if(XXnn="";"";timevalue(now()))`  (nn according to the row XX to the column). This enters the time correctly as a value is entered in the relevant cell. However, when entering a value in any other cell in the sheet, the time value already entered is then also changed to the timevalue(now()). I see from  that the (NOW) function is volatile but does anyone have a work around to suggest? How can one use this formula so that it is persistent and doesn't change when another cell is accessed?

I'm using Google Spreadsheet's  function as a shortcut to insert the current timestamp now.   However, the value in the cell changes whenever the spreadsheet is modified in any way, even when the changes have nothing to do with that particular cell.  How do we stop the value in the cell from being automatically updated?


Suppose $(x, y)$ and $(p, q)$ are coordinates in the plane related by rotation around a fixed point $(a, b)$, as follows: $$\begin{bmatrix} p\\ q\end{bmatrix} = \begin{bmatrix} \cos(t) & -\sin(t) \\ \sin(t) & \cos(t) \end{bmatrix} \begin{bmatrix} x-a \\ y-b \end{bmatrix}$$ where $t$ is the rotation angle. Applying the chain rule show that $u(p(x,y), q(x,y)) $ satisfies $u_{xx}+u_{yy}=0$ iff $u_{pp}+u_{qq}= 0$.  Where would I use chain rule in this problem? I am kind of confused because $u$, $p$, and $q$ are all functions of two variables.

I'm trying to show the Laplace operator is rotationally invariant. Essentially this boils down to showing $$\frac{\partial^2 f}{\partial x^2} + \frac{\partial^2 f}{\partial y^2} = \frac{\partial^2 f}{\partial u^2} + \frac{\partial^2 f}{\partial v^2}$$  where $$u = x \cos \theta + y \sin \theta$$ $$v = -x \sin \theta + y \cos \theta$$  I think I'm on the right track by noting that  $$\frac{\partial^2 f}{\partial x^2} = \frac{\partial}{\partial x}\left(\frac{\partial f}{\partial x}\right) = \frac{\partial}{\partial u}\left(\frac{\partial f}{\partial x}\right)\frac{\partial u}{\partial x} + \frac{\partial}{\partial v}\left(\frac{\partial f}{\partial x}\right)\frac{\partial v}{\partial x}$$ but I'm having difficulty reaching an end game where I show $$\frac{\partial^2 f}{\partial x^2} + \frac{\partial^2 f}{\partial y^2} = \frac{\partial^2 f}{\partial u^2}({\sin}^2 \theta + {\cos}^2 \theta) + \frac{\partial^2 f}{\partial v^2}({\sin}^2 \theta + {\cos}^2 \theta)$$


I'm using Workflow state on a content type. What is the correct HOOK should I use in my custom module to check if the workflow state of the node changed from value to another value to add some actions.

i actually need it for the content_moderation_state entity   function hook_entity_presave(Drupal\Core\Entity\EntityInterface $entity) { if ($entity->getEntityTypeId() !== 'content_moderation_state' ) {     return; }     $moderation_state = $entity->get('moderation_state')->getString();   //code to get the original entity moderation state


I have one page there displaying three different action buttons. As per UX guidelines how to display or style this button and more focus able.   If can be three action level :    Primary Secondary Third

Usually, we only have 2 buttons at the bottom of a form or a page that requires an action: Submit & Cancel.  This one is quite easy to style. However, what if we are dealing with multiple buttons at the bottom of a page? For example:   ← Back | Send Email | Booking Paid | Check-in Guest   I'm thinking of making "Back" just a link (not a button) and making "Send Email" / "Booking Paid" secondary buttons (light gray). Then I'd make "Check-in Guest" as the primary button (green).  I still feel that there's a better way of doing it or dealing with multiple buttons / actions. What do you think?


(I'm assuming that some tags exist on more than one site.)  e.g. I tried doing search across all sites (i.e. here on META), for the tag iOS, by using syntax of [iOS], but the results seem to indicate that it's just finding string matches, rather than restricting the search to just tags.  If this is even possible, what should such a search's syntax look like?

For example, I see there are questions with the  tag on Stack Overflow, but there are also such questions on Super User, Unix/Linux, and other sites in the network.  Is there a way to follow a tag across all of the Stack Exchange sites, so that one can see the global activity of a topic without visiting all the sites separately?


Often after voting to close a question as a duplicate, you come across some other original that is even better, and more fitting. Sometimes, even more than one.   However, you can't suggest that one any more. The only option left to you is to manually add it as a comment. However,    a manually added comment will never make it into the "possible duplicates" section that gets auto-pasted into the question head when it gets closed the comment's link won't be automatically turned into a fancy one with the question title.   I suggest allowing users to suggest as many duplicates as they like, while of course only the first suggestion counts as an actual vote.  Except for not counting as a vote, the additional suggestions would be first-class citizens in that:    they get an auto-inserted possible duplicate of comment they are shown in the "other users suggested these ...." list when voting to close as a dupe they are auto-inserted into the grey "duplicates" box when the question gets closed

When searching for duplicates of a question often multiple ones turn up, but when voting to close only one of them can be specified.  It would be useful to be able to add more than one duplicate link when voting to close.  This is not a duplicate of  as that feature only allows gold-badge users to add multiple targets; this proposal would allow everyone to propose multiple duplicates.


Normally, the close/lock/delete history of a post (including the reversal of such actions) is easily accessible along with the posts revisions.  However, if the post has not been edited (aside from closures/lockings/deletions), there is no link to the revision history, and no indication (aside from maybe comments) that the post was ever closed and reopened, locked and unlocked, or deleted and undeleted.  Example:   Of course, the revision history is still accessible via the direct URL, so the close/lock/delete history can be seen, but there is no indication that such history exists.  I propose that if there are no edits on a question that has been closed, locked, or deleted, there be a link to the revision history in the typical location, with a timestamp of the closure/locking/deletion activity.  It'd be useful to know by looking at the post that there is disagreement as to whether it should be open or closed, locked or unlocked, deleted or undeleted, and it's unclear enough that it's gone both ways without even being edited.    Another example is here:   The question was closed (and then reopened) by a moderator. There is a comment about expanding/improving the question, but no indication that it has been closed/reopened or why.

In the latest  I saw this:     2013-02-18: The revision history of a question that was closed as a duplicate is now showing the chosen originals as part of the "Closed as duplicate" notice.   That sounds cool, so I went to go see what it looks like and realized that questions with , but no edits, don't have an "edited <date>" link to click.  This applies to questions which had a bounty posted, or have been closed, reopened, locked, deleted, etc.  Examples:   , revisions:  , revisions:          I realize I can manually type the URL:  https://meta.stackoverflow.com/posts/168761/revisions   But it would be nice to simply click. It could say "revised" instead of "edited" if there were no edits:


Apex class:  public class ProdImedComAr {     public class Respuesta {         public Integer Codigo;         public String Descripcion;         public Long NroOperacion;         public String MensajeAdic;         private String[] Codigo_type_info = new String[]{'Codigo','http://www.w3.org/2001/XMLSchema','int','1','1','false'};         private String[] Descripcion_type_info = new String[]{'Descripcion','http://www.w3.org/2001/XMLSchema','string','0','1','false'};         private String[] NroOperacion_type_info = new String[]{'NroOperacion','http://www.w3.org/2001/XMLSchema','unsignedLong','1','1','false'};         private String[] MensajeAdic_type_info = new String[]{'MensajeAdic','http://www.w3.org/2001/XMLSchema','string','0','1','false'};         private String[] apex_schema_type_info = new String[]{'https://test.imed.com.ar/','true','false'};         private String[] field_order_type_info = new String[]{'Codigo','Descripcion','NroOperacion','MensajeAdic'};     } }   can someone help me on how to write test class for the above

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So when i go to breed villagers i usually give each one 3 bread. But in this new world i have made to play with a friend they don't want to make babies. When the bread is given to them they have hearts around them but then after a couple of seconds another particle comes up... The particle when you hit them. The gray cloud with lightning i guess that's what it is... Anyone know how to fix that ?

I’ve got one villager up 7 blocks surrounded with 6 doors. On ground level I have villagers who are supposed to breed. They are willing, their inventories are full of potatoes, and I’ve been sitting here for hours.  Hearts are popping up above their heads but nothing happens. I am playing on Xbox One.


I have been learning basic statistical testing as it relates to agriculture and have become familiar with the common practice of summing squared raw deviation values, whether in something simple like a standard deviation calculation or something more complex, like ANOVA and Chi square.   I understand the logic in squaring the values so that negative numbers do not reduce the total sum of squares to zero. It makes sense. But when working with deviations that are decimals between -1 and 1 the act of squaring the values reduces the sum of squares, which is counter intuitive to the idea of squaring the values in the first place.   Why is the reduction in overall sum associated with squaring simple deviations between -1 and 1 acceptable? That part of the process seems to run in opposition to the concept of squaring the values in the first place.

In the definition of standard deviation, why do we have to square the difference from the mean to get the mean (E) and take the square root back at the end? Can't we just simply take the absolute value of the difference instead and get the expected value (mean) of those, and wouldn't that also show the variation of the data? The number is going to be different from square method (the absolute-value method will be smaller), but it should still show the spread of data. Anybody know why we take this square approach as a standard?  The definition of standard deviation:  $\sigma = \sqrt{E\left[\left(X - \mu\right)^2\right]}.$   Can't we just take the absolute value instead and still be a good measurement?  $\sigma = E\left[|X - \mu|\right]$