Connecting all points to each other in QGIS
Creating all possible line segments between all points using QGIS
No custom off topic message when flagging on SO I have less than 3000 rep on StackOverflow. Now that the new closing changes are live, I cannot supply a custom off topic message:    I can enter a custom off topic flag message without issue here on meta, though it only has three canned off topic reasons, rather than five.  I'm not sure if this is the same for users with enough rep to vote to close directly, but the lack of a custom message eliminates the ability to use the correct flag reason in some cases.  For example, I wanted to flag , which is simply off topic on SO. However, I can't use a custom message, and none of the canned ones are appropriate.    appears to be the most up to date official information on custom reasons, and indicates that they are remaining in play for now.  supports that.  If this is by design, how should I flag such questions? This is not a case worth bothering the mods over, so I don't want to use a custom diamond attention flag. difference between accuracy and Rand index (R) I'm very confused, when I read on the wikipedia "From a mathematical standpoint, Rand index is related to the accuracy, but is applicable even when class labels are not used."   and   But when I use in R the rand.index function from fossil package and the Accuracy function from MLmetrics it doesn't give the same answer  &gt; Accuracy(predicted, real) [1] 0.8266667  &gt; rand.index(predicted,real) [1] 0.7114989  Please can someone explain to me the difference between these two and which one should I use?  NB:I use the k-medoids clustering algorithm (function pam from cluster package) What is scientific mind? Terms for collections of animals As I watched the murder of crows sitting on the line above my house this evening, I got wondering where all of the collective nouns for animals (pod of whales, gaggle of geese, pride of lions) came from and why we need so many.    If sheep can be a flock, why can't whales, geese, lions, and crows? I know that symlinks have a separated inode from the original file and that they only point for the inode containing the data. My question is, where is the hardlink name stored if there's no field in the inode structure refering to "name". I know that this could be a a relatively easy question, but as all hardlinks have the same inode number i assume that no inode is created when creating a hard link. proving logical equivalence $(P \leftrightarrow Q) \equiv (P \wedge Q) \vee (\neg P \wedge \neg Q)$ I am currently working through Velleman's book How To Prove It and was asked to prove the following  $(P \leftrightarrow Q) \equiv (P \wedge Q) \vee (\neg P \wedge \neg Q)$  This is my work thus far  $(P \to Q) \wedge (Q \to P)$  $(\neg P \vee Q) \wedge (\neg Q \vee P)$ (since $(P \to Q) \equiv (\neg P \vee Q)$)  $\neg[\neg(\neg P \vee Q) \vee \neg (\neg Q \vee P)]$ (Demorgan's Law)  $\neg [(P \wedge \neg Q) \vee (Q \wedge \neg P)]$ (Demorgan's Law)  At this point I am little unsure how to proceed.   Here are a few things I've tried or considered thus far:  I thought that I could perhaps switch some of the terms in step 3 using the law of associativity however the $\neg$ on the outside of the two terms prevents me from doing so (constructing a truth table for $\neg (\neg P \vee Q) \vee (\neg Q \vee P)$ and $\neg (\neg P \vee \neg Q) \vee \neg (P \vee Q)$ for sanity purposes)  I can't seem to apply the law of distribution since the corresponding terms are negated.  Applying demorgans law to one of the terms individually on step 2 or 3 doesnt seem to get me very far either.  Did I perhaps skip something? Am I even on the right track? Any help is appreciated Which form should be used for at­tribu­tive nouns like “stu­dent union”: sin­gu­lar or plu­ral, or pos­ses­sive sin­gu­lar or pos­ses­sive plu­ral? When should a noun that’s used at­tribu­tively to de­scribe an­other  noun be plu­ral, and when should it be sin­gu­lar?  And when should it be pos­ses­sive, like bak­er’s dozen and when should it be plu­ral pos­ses­sive, like farm­ers’ mar­ket?  In other words, why do we say teach­ers union rather than teacher  union?  And why do we say wed­ding plan­ner rather than wed­dings plan­ner?  Which of these vari­ants is or are cor­rect?        stu­dent union   stu­dents union   stu­den­t’s union   stu­dents’ union      What about com­mu­nity val­ues ver­sus com­mu­ni­ty’s val­ues?  Please note I am look­ing for a gen­eral rule or at least some tips.  These are only ex­am­ples.  Up­date: It seems even na­tive speak­ers fol­low their per­sonal  style to write such com­pound words. I won­der why in the IELTS lis­ten­ing sec­tion, the lan­guage learner has to write a spe­ci­fic form and there is no rule for this. Blender 2.78 with Windows 10 lags when interacting with the UI How do we see? Where do the photons disappear? Brasero says it won't burn the CD because the file is too big, what's going on? Last seen not updating when using Android app This isn't directly related to the app, but probably more on the APIs it's using. The last seen on the profile page doesn't seem to reflect that I'm actively using the Android app, or taking actions. I was able to vote on items and the last seen property on the profile page said I was last seen 50 minutes ago, when I was using a computer.  I'm assuming it won't count as a visit for the Enthusiast and Fantic badges either. I don't want someone angrily posting on Meta swearing they used the app for a day, yet they lost the consecutive days and has to prove it by showing they voted for something (we're probably far from this situation since it's alpha...) JavaScript private methods To make a JavaScript class with a public method I'd do something like:  function Restaurant() {}  Restaurant.prototype.buy_food = function(){    // something here }  Restaurant.prototype.use_restroom = function(){    // something here }   That way users of my class can:  var restaurant = new Restaurant(); restaurant.buy_food(); restaurant.use_restroom();   How do I create a private method that can be called by the buy_food and use_restroom methods but not externally by users of the class?  In other words, I want my method implementation to be able to do:  Restaurant.prototype.use_restroom = function() {    this.private_stuff(); }   But this shouldn't work:  var r = new Restaurant(); r.private_stuff();   How do I define private_stuff as a private method so both of these hold true?  I've read  a few times but it doesn't seem like "private" methods can be called by public methods and "privileged" methods can be called externally. 80's Animated movie: An old man joins mission to save a boy stranded on a hostile world sort() and reverse() functions do not work How to add Excel sheet to console application How can I determine how much bleed to use? ORA-00918: column ambiguously defined in SELECT * I like to be thorough, but if you feel confident you can skip the first paragraph.  Review: A ring is a set $R$ endowed with two operations of + and $\cdot$ such that $(G,+)$ is an additive abelian group, multiplication is associative, $R$ contains the multiplicative identity (denoted with 1), and the distributive law holds.  If multiplication is also commutative, we say $R$ is a commutative ring. A ring that has no zero divisors (non-zero elements whose product is zero) is called an integral domain, or just a domain.  We want to show that for a domain, the equation $x^2 = 1$ has at most 2 solutions in $R$ (one of which is the trivial solution 1).    Here's what I did:   For simplicity let $1,a,b$ and $c$ be distinct non-zero elements in $R$.  Assume $a^2 = 1$.  We want to show that letting $b^2 = 1$ as well will lead to a contradiction.  So suppose $b^2 = 1$, then it follows that $a^2b^2 = (ab)^2 = 1$, so $ab$ is a solution as well, but is it a new solution?  If $ab = 1$, then $abb = 1b \Rightarrow a = b$ which is a contradiction.  If $ab = a$, then $aab = aa \Rightarrow b = 1$ which is also a contradiction.  Similarly, $ab = b$ won't work either.  So it must be that $ab = c$.  So by "admitting" $b$ as a solution, we're forced to admit $c$ as well.  So far we have $a^2 = b^2 = c^2 = 1$ and $ab = c$.  We can procede as before as say that $(abc)^2 = 1$, so $abc$ is a solution, but once again we should check if it is a new solution.  From $ab = c$, we get $a = cb$ and $b = ac$, so $abc = (cb)(ac)(ab) = (abc)^2 = 1$.  So $abc$ is not a new solution; it's just one.  At this point I'm stuck.  I've shown that it is in fact possible to have a ring with 4 distinct elements, namely $1,a,b$ and $c$ such that each satisfies the equation $x^2 = 1$ and $abc = 1$.  What am I missing? ReSharper likes to point out multiple functions per ASP.NET page that could be made static. Does it help me if I do make them static? Should I make them static and move them to a utility class? How do I disable DVD auto eject in Windows 7? I just discovered an incredibly annoying "feature" of Windows 7 tonight.  If you click on your optical drive in Explorer, and there is no disc in the drive, Windows 7 is kind enough to open the tray for you.  I'm finding it hard to contain my rage over this idiotic design decision.  WTF?  According to , this behavior was apparently introduced in Vista.  The author posted a workaround, but I don't want a workaround.  I want it to stop doing this.  Like he, I have a case with a door that covers the drive bays.  If it's closed, and I accidentally click on that optical drive, it knocks on that door 10 or 12 times before giving up.  Can this behavior be turned off in Windows 7?