How to bake Simple Deform modifier animation for exporting?

I've animated my object with Simple Deform modifier (keyframed Angle property in Bend tab) and i would like to export this animation into game engine via .fbx. If i'm not wrong, i need to bake animations first, but i don't know how to bake modifier animation. "Bake Action" doesn't work, it just removes Simple Deform modifier, but animation is not baked after that.  Edit: I've discovered that i can "Apply As Shape Key", but baking shape keys also seems not to work...


How to compare the Firebase retrieved value with a string?

Is there a way I can store the value retrieved from the Firebase to be stored in a String Variable? Here is my code retrieving the Value of "rface":  ref.addListenerForSingleValueEvent(new com.google.firebase.database.ValueEventListener() {                 @Override                 public void onDataChange(com.google.firebase.database.DataSnapshot dataSnapshot) {                     rface = dataSnapshot.child("face").getValue(String.class);                 }                  @Override                 public void onCancelled(DatabaseError databaseError) {                 }             });   And I want to implement and if condition:  if (rface=="0") {     do this }   The rface contains a string value in my Firebase Database. When I try to use this If condition Android Studio says:      Operator "==" can not be applied to 'java.util.Objects','java.lang.String'


How do I make smoke fill a specific object

How do I make it so that smoke only fits a specific object like a cube or sphere so the smoke makes the shape of the object.  Let's say I have a single object of a hat and what I want to do is make the smoke in the shape of the hat.  Help


linker error when trying to serialize a vector of objects with boost

I've lost so much time on this problem. I have two classes, one for a set of cards   #include <boost/serialization/vector.hpp> #include <boost/archive/text_oarchive.hpp> #include <boost/archive/text_iarchive.hpp> #include <vector>  class Set { private:   friend class boost::serialization::access;   std::string _name;   std::vector<Card*> _cards;  public:   template <class Archive>   void serialize(Archive & ar, const unsigned int version);   Set(); };   And an other for a card itself :  class Card {    private:     friend class boost::serialization::access;       std::string _front;     std::string _back;     std::vector<CardReview> _reviews;        public:     template <class Archive>     void serialize( Archive & ar, const unsigned int version);     Card();  };   Here are my serializers :   template <class Archive> void Set::serialize ( Archive & ar, const unsigned int version ) {   ar & _cards; // If I comment this line, everything works !!   ar & _name; }  template <class Archive> void Card::serialize ( Archive & ar, const unsigned int version ) {     ar & _back;     ar & _front;     ar & _id;     ar & _reviews; }   Unless I comment the line serializing the vector of cards called _cards, I get the following linker error :  [ 33%] Building CXX object CMakeFiles/supercards.dir/set.o Linking CXX executable supercards CMakeFiles/supercards.dir/set.o: In function `void boost::serialization::access::serialize<boost::archive::text_oarchive, Card>(boost::archive::text_oarchive&, Card&, unsigned int)': set.cpp:(.text._ZN5boost13serialization6access9serializeINS_7archive13text_oarchiveE4CardEEvRT_RT0_j[_ZN5boost13serialization6access9serializeINS_7archive13text_oarchiveE4CardEEvRT_RT0_j]+0x1b): undefined reference to `void Card::serialize<boost::archive::text_oarchive>(boost::archive::text_oarchive&, unsigned int)' CMakeFiles/supercards.dir/set.o: In function `void boost::serialization::access::serialize<boost::archive::text_iarchive, Card>(boost::archive::text_iarchive&, Card&, unsigned int)': set.cpp:(.text._ZN5boost13serialization6access9serializeINS_7archive13text_iarchiveE4CardEEvRT_RT0_j[_ZN5boost13serialization6access9serializeINS_7archive13text_iarchiveE4CardEEvRT_RT0_j]+0x1b): undefined reference to `void Card::serialize<boost::archive::text_iarchive>(boost::archive::text_iarchive&, unsigned int)' collect2: error: ld returned 1 exit status make[2]: *** [supercards] Error 1 make[1]: *** [CMakeFiles/supercards.dir/all] Error 2 make: *** [all] Error 2 *** Failure: Exit code 2 ***   I really don't understand why this is happening. If I comment the above mentioned line, there is no compile-time error and the serialization works fine - but the _cards property is not included of course. So this not a linker error, the library is correctly linked. I've spent 3 hours trying to find out what is missing in my code without success.  Any idea would be appreciated,  Thanks !


SqlServer: can one table's PK be the FK of other two table's?

I have three tables project, users and proj_user.  The PK of proj_user table is the FK of project and users table's pk e.g.(project_id,user_id)  My question is, is it possible for the project_id and user_id's data to be different, like?: project_id = '12345' and user_id = 'abc987'    Edit Thanks for the quick response. But just look at this scenario  TABLE project (     project_id PRIMARY KEY     ... )  TABLE users (     user_id PRIMARY KEY     ... )  TABLE proj_user ( proj_user_id project_id user_id PRIMARY KEY (proj_user_id), FOREIGN KEY (proj_user_id) REFERENCES projects (project_id), FOREIGN KEY (proj_user_id) REFERENCES projects (user_id) )   I want the project_id and user_id values to be different.  What do I need to change here?


Calculating optimal number of bins in a histogram

I'm interested in finding as optimal of a method as I can for determining how many bins I should use in a histogram. My data should range from 30 to 350 objects at most, and in particular I'm trying to apply thresholding (like Otsu's method) where "good" objects, which I should have fewer of and should be more spread out, are separated from "bad" objects, which should be more dense in value. A concrete value would have a score of 1-10 for each object. I'd had 5-10 objects with scores 6-10, and 20-25 objects with scores 1-4. I'd like to find a histogram binning pattern that generally allows something like Otsu's method to threshold off the low scoring objects. However, in the implementation of Otsu's I've seen, the bin size was 256, and often I have many fewer data points that 256, which to me suggests that 256 is not a good bin number. With so few data, what approaches should I take to calculating the number of bins to use?


Prove the following identity by counting two sets of partitions in two different ways.  \begin{equation}\prod_{i\geq 0}(1+x^{2i+1})=1 + \sum_{n\gt 0}x^{n^2}\prod_{j=1}^n\frac{1}{1-x^{2j}}.\end{equation}  I know the partition on the left side, it's the number of partitions with $i$ distinct odd parts. I just need help doing the right side. The second part of the second term , the product is the number of partitions of $n$ and for each $i$, the parts of size $i$ occur an even number of times. Now it's being multiplied by the summations of $x^{n^2}$ times. How would that effect the partition?


Will Fermat's last theorem hold true on the Complex Plane?

Fermat's Last Theorem      In number theory, Fermat's Last Theorem (sometimes called Fermat's conjecture, especially in older texts) states that no three positive integers a, b, and c can satisfy the equation $a^n + b^n = c^n$ for any integer value of $n$ greater than two.   Now the question is will Fermat's last theorem hold true if we extend the question to the complex plane. Ie when $a$, $b$ or $c$ can be complex numbers. Why or Why not and is there any prove to it?


ORA-00933: SQL command not properly ended In an Insert command

I tried to look for this online and read my code, but I wasn't able to find a solution.   I am using ORACLE Application Express 11G Edition.   Insert into Owner(O_ID, O_First, O_Last, O_Line, O_City, O_State, O_Zip,  O_Phone, O_Email)  VALUES   (1102, "Chris", "Leaves", "141-17 Union Turnpike Apt 3P","Flushing", "NY",  "11367", "7182105108","chris2@gmail.com"),  (1433, "Steve", "Jobs", "88-12 Main Street","Flushing", "NY", "11367",  "7189998476", "steve12@gmail.com"),  (2443, "Chris", "Melvin", "151-17 Jewel Avenue","Flushing", "NY", "11367",  "7189971034","chris41@yahoo.com"),  (2425, "John", "Fellow", "131-14 Bell Blvd","Bayside", "NY", "11361",  "7184413254","john32@yahoo.com"),  (2645, "Fish", "Mini", "171-14 169 Street", "Fresh Meadows", "NY", "11366",  "7184435489","fish4ever@yahoo.com"),  (3514, "Aaron", "Hernadez", "51-14 Hollis Avenue","Hollis", "NY", "11423",  "7185617865", "aaron81@gmail.com"),  (3621, "Gang", "Taylor", "230-11 Hillside Avenue","Queens Village", "NY",  "11427", "7187764728", "Wiztaylor@gmail.com"),  (4214, "Brock", "Obama", "260-04 Hillside Avenue", "Bellerose", "NY",  "11004", "7183432536", "brockobama@gmail.com"),    (4314, "Astro", "Miller", "58-45 251st Street", "Little Neck", "NY",  "11362", "7182156709", "astro214@yahoo.com"),  (4423, "Bin", "Bulu", "58-50 251st Street","Little Neck", "NY", "11362",  "7185437832", "binbulu@gmail.com"),  (4928, "Alvin", "Chimp", "15 Garden Street", "Great Neck", "NY", "11021",  "5168297189", "ChimpA21@gmail.com"),  (7841, "Allen", "Clover", "105 Station Road", "Great Neck", "NY", "11023",  "5168298965", "allenC3242@yahoo.com"),  (4547, "Aiden", "Wyness", "28 Berkley Street", "Valley Stream", "NY",  "11581", "5168258952", "aiden32421@gmail.com"),  (7849, "Derek", "Williams", "56 Hoffman Street", "Valley Stream", "NY",  "11580", "5167918912", "DWill23@yahoo.com"),  (1892, "Antonio", "Burito", "3522 101st Street","Corona", "NY", "11368",  "7182715567", "antonio212112@gamil.com"),  (5627, "Bob", "Iverson", "10912 34th Ave","Corona", "NY", "11368",  "7185928911","Bobiverson23@gmail.com"),  (7829, "Phil", "Chang", "387 Andrews Rd","Mineola","NY","11501",  "5168331106", "phillchang9@gmail.com"),  (8526, "Jacky", "Chu", "313 Columbus Pkwy", "Mineola", "NY", "11501",  "5162487912", "jackychu54@gmail.com"),  (1720, "Kiba", "Wolf", "122 Beech St","Floral Park", "NY", "11001",  "5163305792", "kibawolf4@gmail.com"),  (1920, "Kakashi", "Hatake", "40 Beechhurst Ave","Floral Park", "NY", "11001",  "5168309910", "HatakeKaskashi@gmail.com");   This is just sample data, for example reasons. I encountered this error:      ORA-00933: SQL command not properly ended.    I don't know what is the reason for this, even though I am following the syntax    INSERT INTO table_name VALUES (value1, value2, value3, ...);    Any help would be great thank you in advance!.


Physical Explanation for "Kolmogorov -5/3 spectrum" in Fluid Mechanics

According to Kolmogorov, the energy spectrum function of a turbulent fluid is given as,  $E(k)=C\epsilon^{\frac{2}{3}}k^{\frac{-5}{3}}$  where $\epsilon$ is the energy flux and $k=\frac{2\pi}{r}$ where $r$ is the length scale.   The normal explanation I see in most physics texts and articles is that the -5/3 exponent is found purely through dimensional analysis. Obviously dimensional analysis is very useful, but often times there is a more physical explanation as well. Does anyone have any insights?


How do I identify SMD components? (or how do I identify any component)

How do I identify the markings on an SMT component and match it up with a part number so I can be a good designer and actually look at a datasheet (and read the whole thing)? Or identify a part to replace an unknown part on a PCB?


Immediately returns to login screen after logging in

So I just had a software update on ubuntu 14.04 and now when I try to login, it just sits there for a few seconds then returns to the login screen. I've tried restarting and doing a few things I found on the web but none of them helped. If you can, please help!


I need a good book for learning mechanics in non-inertial frames

I'm studying classical mechanics, but without those stuffs Lagrangians and Hamiltonian mechanics...just Newtonian..the problem is a find hard to learn this non-inertial frames system, like $r=R+r'$...only that I find difficuly, because they say "the absolute vector is the sum of the distance between the origins and the relative vector of the rotating system", but how can I add two vector of different basis systems? How can I say after I add these two vectors of different basis axis, and say that the result, belongs necessarily to the first basis system? Can anyone tell me about a book that goes deep into this with a good amount of graphics and examples?


Ping times keep oscillating on Wi-Fi: Boom network load?

I have a 2012 retina MacBook Pro that lags in a very specific way: I have normal ping times for about 5 seconds and then they spike to 100-300ms more than normal for about 5 seconds, and back and forth. Example:  64 bytes from 216.58.192.46: icmp_seq=844 ttl=58 time=5.694 ms 64 bytes from 216.58.192.46: icmp_seq=845 ttl=58 time=5.508 ms 64 bytes from 216.58.192.46: icmp_seq=846 ttl=58 time=6.203 ms 64 bytes from 216.58.192.46: icmp_seq=847 ttl=58 time=6.665 ms 64 bytes from 216.58.192.46: icmp_seq=848 ttl=58 time=6.074 ms 64 bytes from 216.58.192.46: icmp_seq=849 ttl=58 time=7.480 ms 64 bytes from 216.58.192.46: icmp_seq=850 ttl=58 time=54.219 ms 64 bytes from 216.58.192.46: icmp_seq=851 ttl=58 time=101.125 ms 64 bytes from 216.58.192.46: icmp_seq=852 ttl=58 time=144.924 ms 64 bytes from 216.58.192.46: icmp_seq=853 ttl=58 time=188.527 ms 64 bytes from 216.58.192.46: icmp_seq=854 ttl=58 time=5.604 ms 64 bytes from 216.58.192.46: icmp_seq=855 ttl=58 time=5.553 ms 64 bytes from 216.58.192.46: icmp_seq=856 ttl=58 time=9.515 ms 64 bytes from 216.58.192.46: icmp_seq=857 ttl=58 time=5.364 ms 64 bytes from 216.58.192.46: icmp_seq=858 ttl=58 time=16.086 ms 64 bytes from 216.58.192.46: icmp_seq=859 ttl=58 time=8.182 ms 64 bytes from 216.58.192.46: icmp_seq=860 ttl=58 time=28.378 ms 64 bytes from 216.58.192.46: icmp_seq=861 ttl=58 time=27.358 ms 64 bytes from 216.58.192.46: icmp_seq=862 ttl=58 time=73.504 ms 64 bytes from 216.58.192.46: icmp_seq=863 ttl=58 time=119.722 ms 64 bytes from 216.58.192.46: icmp_seq=864 ttl=58 time=174.853 ms 64 bytes from 216.58.192.46: icmp_seq=865 ttl=58 time=210.945 ms   And so on. It does this at home and at work, and plugging into ethernet via thunderbolt does not exhibit these behaviors. I don't have corresponding spikes in CPU usage so I'm unsure of how to track this issue down.  Please help!  EDIT:  After doing a binary search of killing apps, I have discovered that killing the  app causes the spikes to go away, which is strange because I wouldn't figure that an audio enhancement app would have anything to do with the network. It's not sending or receiving bytes according to Activity Monitor, but merely being active somehow causes ping times to fluctuate in this manner only on wifi. Anybody have an inkling of why this might be the case?


Show that $a_n<\sqrt{2}$ for every $n\in\mathbb{N}$.

We define $a_1=1$ and $a_{n+1}=\dfrac{1}{2}\left(a_n+\dfrac{2}{a_n}\right)$.  I want to prove that $a_n$ converges. But first I'd like to show that $a_n<\sqrt{2}$ for every $n\in\mathbb{N}$.  I try to use induction. For a fixed $n$, I suppose that $a_n<\sqrt{2}$.  Any hint to prove that $a_{n+1}=\dfrac{1}{2}\left(a_n+\dfrac{2}{a_n}\right)<\sqrt{2}$?  Thanks.


What is this design style called in which lots of simple polygons make up an image?

What is the design style called where they create form with simple shapes, usually triangles like they have done with the ground in the    Or like the images below:


Bluetooth speaker and buds: Delay in playback, truncates short sounds

Recent android phone.  I initially observed this issue just with Boom and Megaboom bluetooth speakers, but I now have Jabra buds, and see the same issue:  The first 100-500 milliseconds of audio do not play.  This is an issue if it is a language app (that says a word), or a workout app (that says "start" and then 30 seconds later says "stop") because all or most of the sound does not play at all.  What is the resolution?  I have been forced to use wired buds for language learning (which is NO fun!)  When I used apple airpods I did NOT have this issue. (I no longer use airpods because they  or battery-replaced)


How to prove $f(x,y)$ is continuos in $\left(x_{0},y_{0}\right)$?

Is there any standard method to prove that an arbitrary $f:\mathbb{R}^{2}\mapsto\mathbb{R}$ function is continuous in a given $\left(x_{0},y_{0}\right)$ point? If I consider the definition of continuity  in the case of $f:\mathbb{R}\mapsto\mathbb{R}$, then I take the limits of $f(x)$ from the left and from the right side in $x_0$. If $$\lim_{x\rightarrow x_{0}-}f\left(x\right)=\lim_{x\rightarrow x_{0}+}f\left(x\right)=f\left(x_{0}\right),$$ then I say $f$ is continuous in $x_0$, but I can't do this in $\mathbb{R}^{2}$ because there are infinity possibilities to approach $\left(x_{0},y_{0}\right)$. (In the case of $f:\mathbb{R}\mapsto\mathbb{R}$ there are only two ways to approach $x_0$: from the right and from the left.) What can I do in $\mathbb{R}^{2}$ or more generally in  $\mathbb{R}^{n}$? It is much easier to prove something is not continuous, because if I find at least one case when $$\lim_{\left(x,y\right)\rightarrow\left(x_{0},y_{0}\right)}f\left(x,y\right)\neq f\left(x_{0},y_{0}\right)$$ happens, then I can say $f$ is not continuous in  $\left(x_{0},y_{0}\right)$, but it is not the question just a remark. If there is no standard method then can you say any trick what could be useful here?


Off-by-one error on "X new answers to this question"

While perusing a question on Stack Overflow, I was presented with the familiar "X new answer to this question, click to refresh". When I did, I was presented with the following:    This pattern continued with "4 new answers" and "5 new answers", at which point I got bored watching it and came here to report it.  FWIW, the correct number of answers was displayed when I did an F5 on it.


Is there any way to set up pin or password for a directory and file in ubuntu?

I wanted to lock any directory with a password, is it possible to set up pin or password for any directory or file without using third party tools like cryptkeeper.


Prove that $a\sin x+b\cos x=\sqrt{a^2+b^2} \sin\left(x+\tan^{-1}\left(\frac{b}{a}\right)\right)$

Recently, I came across a beautiful question. I tried several ways of solving it, but I could not reach anywhere. The question goes like:  Prove that:  $$a\sin x+b\cos x=\sqrt{a^2+b^2} \sin\left(x+\tan^{-1}\left(\frac{b}{a}\right)\right)$$  Please give me a hint. Thanks in advance.


Desktop or Taskbar shortcut of shellscript - easiest way with 18.04 LTS?

I'm new to ubuntu and Linux and just installed Ubuntu 18.04 LTS.  I know there are tons of tutorials out there how someone could create a shortcut. Unfortunately none of them really worked for me.  I have a ~/shellscript.sh which I'd need to call periodically.  How can I create a shellscript launcher as simply as   e.g. ln -s ~/shellscript.sh ~/Desktop/run-shellscript  where I simply can click on it to run it? (Remark: ln command above doesn't work)  Thanks for your contributions!


NullPointerException while checking if array is empty

I'm getting a NullPointerException when i'm checking if the length of the array is equal to 0 or not, and I can't find why it isn't working. Anyone could tell me what i'm doing wrong ? Here's my entire function code:      public static ArrayList<String> searchZone(Player p){     openConnection();     ArrayList<String> data = new ArrayList<String>();     WorldEditPlugin worldEdit = (WorldEditPlugin) Bukkit.getServer().getPluginManager().getPlugin("WorldEdit");     Selection selection = worldEdit.getSelection(p);     String query = "SELECT * FROM " + db + ".blocks";     ArrayList<String> res = executeQueryWe(query);     String[] items = res.toArray(new String[res.size()]);     int i = 0;     int iters = items.length;     while(i < iters){         try{         if(selection != null){             String[] locs = items[i].split(",");             World world = Bukkit.getServer().getWorld(locs[0]);             int x = Integer.valueOf(locs[1]);             int y = Integer.valueOf(locs[2]);             int z = Integer.valueOf(locs[3]);             Location loc = new Location(world, x, y ,z);             if(selection.contains(loc)){                  String query2 = "SELECT * FROM `blocks` WHERE `world`='" + world.getName() + "' AND `x`='" + x + "' AND `y`='" + y + "' AND `z`='" + z + "';";                 data = executeQuery(query2);             }         }         } catch(Exception e){             closeConnection();             p.sendMessage(prefix + ChatColor.RED + "An error occured while reading database");             break;         }         p.sendMessage(prefix + ChatColor.RED + "Please make a selection first");         break;     }     if(data.size() != 0){ //<---------------------------- ERROR COMES FROM HERE         closeConnection();         return data;     } else {         data.add("No entries has been found.");         closeConnection();         return data;     } }


Button text for 'Are you sure you want to cancel this order' alert?

I'm working on an eCommerce site where we're implementing a feature that allows the user to cancel an order (of physical goods) that's in transit.   On the line item (parcel level) the user can 'cancel this parcel'.  On Click, I want to display a warning along the lines of: Are you sure you want to cancel this parcel? This cannot be undone.   Here's the bit I'm struggling with.  There should be a positive Yes, I want to cancel, and a negative, No I do not want to cancel.   It feels like I've got to be cognisant of the word 'cancel' in this solution.   The cancel of the cancel order action might cause confusion unless I get it crystal clear.  Any ideas on the button text for the two options?  I want to keep the button actions super clear, easy to understand and not too long.


I have a problem with a hard disk. This used to be in my Lacie Network Space 2, but it crashed.  Under Windows I don't get to see anything, of course, so I ordered a USB - SATA cable, and a live boot USB from Ubuntu.  So far, that's what I have done. Because otherwise I am a layman and I try everything to get my photos/videos back.  To be precise, when I start Ubuntu, I get the following message when I click on the disk:  Error mounting /dev/sda2 at /media/ubuntu /cea89a46-6cf3-492e-80f3-d270280237ac: can't read superblock on /dev/sda2


ispalindrome recursive function in JavaScript

This function is not sum correctly. sum=1    aj=121 sum=12   aj=12 sum=121          aj=1 This is not show in the alert.   // declaring the recursive function /////////////////////////////////////////////////// function isPal(aj, n) {   var sum = 0;   //alert("aj=" + aj);   if (Math.trunc(aj) != 0) {      sum = sum * 10 + aj % 10;      alert("sum=" + sum + " aj= " + aj + " n=" + n);     isPal(aj / 10, n); // recursive call same as while(n!=0) using loop   } else if (sum == n)     return 1;   else     return 0; } //////////////////////////////////////////////////// var palindrome; n = parseInt(prompt("Enter a number to check for Palindrome", "121")); palindrome = isPal(n, n); alert("palindrome = " + palindrome); if (palindrome == 1)   alert(n + " is palindrome\n"); else   alert(n + " is not palindrome\n");


Past perfect or Simple Past: "I had [had] a hard day"

Question :  I was really tired last night. I ______________ (have) a hard day.   Which one of the two is correct sentence and why?  (by the way I wrote the second one.)   I was really tired last night. I had had a hard day.  I was really tired last night. I had  a hard day.    When do we use had had or have have together?


Ethernet: how important is the magnetics topology?

I have some Ethernet issues with a set of boards (6/10 are bad). They're possibly just assembly house mistakes... but I'm very concerned about my magnetics jack.  I could have sworn I saw a example schematic with my jack's topology used with my PHY before, but I can't find it. The PHY's datasheet and suggested magnetics jacks are all identical in topology, and very different than what I have.  I'm using a SMSC  PHY, with a Bel  magnetics jack.  The transformer ratios on my jack vs. a suggested jack for this PHY like the  are the same (1:1).  The inductance is the same, 350uH. However, the choke on mine is on the circuit side, not network side. Also, while the TLA has four 75 ohm resistors from taps tied to a single 1nF/2kV cap, mine has an extra set of 1nF caps between the taps and the 75 ohm resistors.  The main difference is that my jack is a POE jack, and I thought I found an example that used one exactly like it. So, the topology is obviously different just because of that feature.  At the moment, I have 4 good boards, 1 'sometimes' board, and 5 boards that just blink a LED at 11.68Hz representing some error that no datasheet explains.  How important is this? Of course there's no other jack with that footprint.  EDIT  I added some detail on the magnetics jacks above. I was just recommended the SI-60152-F, so I'll compare to that one. Of course like all the other recommendations... it also has no stock at anyone on FindChips.  LATE EDIT  It turns out my problem was the crystal layout that fed the Ethernet PLL.  On the respin, I went with a more standard non-POE jack.


Doubts in an introduction to classical field theory

I started to study classical field theory using the book "Field Quantization" of Greiner and Reinhardt, and I have some doubts. First, the book write the Lagrangian $L(t)$ as a functional of a field $\phi(\textbf{x},t)$:  $$L(t) = L[\phi(\textbf{x},t), \dot{\phi}(\textbf{x},t)].$$ After, it defines the Lagrange density $\mathcal{L}$ by $$L(t) = \int d^{3}x \mathcal{L} ( \phi(\textbf{x},t), \nabla \phi(\textbf{x},t), \dot{\phi}(\textbf{x},t)),$$ and the book compute the variation in $L$: $$\delta L (t) = \int d^{3}x\  \delta \mathcal{L} = \int d^{3}x\ \left( \frac{\partial \mathcal{L}}{\partial \phi}\delta \phi + \frac{\partial \mathcal{L}}{\partial (\nabla \phi)}\delta \nabla \phi + \frac{\partial \mathcal{L}}{\partial \dot{\phi}}\delta \dot{\phi} \right),$$ Using that $\delta \nabla \phi = \nabla \delta \phi $ and integrating by parts the second term, it gives $$\int d^{3}x \nabla \frac{\partial \mathcal{L}}{\partial (\nabla \phi)}\nabla \delta \phi  = \int d^{3}x \nabla \left( \frac{\partial \mathcal{L}}{\partial (\nabla \phi)}\delta \phi \right) - \int d^{3}x \left(\nabla \frac{\partial \mathcal{L}}{\partial (\nabla \phi)} \right)\delta \phi.$$ But the book consider only the second term of the second member of the expression above. The first integral should be zero, but why?


Can I Change/Cancel My Hotel Bookings after getting Schengen visa, will that get my visa cancelled?

I made the hotel reservations in Spain and the Netherlands, I received the visa. I recently found a better deal on internet, in that case can I cancel the booking I presented in the Itinerary provided for visa and are the hotels in the Netherlands and Spain liable to inform embassy in case of hotel booking cancellation ?


Made a kit on Saturday, 1/2 lb. Caramel 80 specialty grain, 9.15 lbs rye extract. Kit came with the Wyeast American Ale smack pack. When I got the yeast pack out of the fridge, the pack was already smacked, so to speak. The inner sugar pod had already been breached at some indeterminate time, and so the yeast had eaten and gassed, etc. Since I had no idea when this had happened, I figured I was better off using some of the dry yeast I had on hand. So, I pitched 1 packet of Safale-05 Saturday around 5PM.   Sunday went by, blowoff tube was quiet, and I started thinking one packet wasn't going to be able to deal with 1.075 SG. Sunday night I went to my fridge full of jars, pulled out the jar of S-05 culture, made 2 pints of starter with a half cup of dextrose and poured that in Monday morning. Before opening the bucket lid to add the starter Monday morning, the blowoff tube was burping a little bit, so I figured the extra yeast would make sure everything got going great. Since then, silence. No activity as far as I can tell. It's pretty cool where the bucket is, air temp around 64, and the bucket was sitting on the tile/concrete floor. So I put it in a tub this morning and filled it up with 65 degree water. Did I pitch 32 oz. of infection/disaster into a fermentation that was doing ok? Or is the cool temp keeping things from getting going?


Looking for insightful explanation as to why right inverse equals left inverse for square invertible  matrices

The simple proof goes:  Let B be the left inverse of A, C the right inverse.  C = (BA)C = B(AC) = B  This proof relies on associativity yet does not give any insight as to why this surprising fact about matrices is true.  AC means a bunch of linear combinations of of columns of A. CA means a bunch of linear combinations of rows of A. Completely different numbers get multiplied in each case.  The proof above is just a bunch of syntactical steps not having much to do with matrices directly, I cannot see how CA=AC=I.  Can anyone shed some light on this?


$a_n=(1+\frac{1}{n})^n$ and $n\geq 1$ I check first $n\to \infty$ then $\lim_{n\to \infty}=(1+\frac{1}{\infty})^\infty$ $=(1+0)^\infty=1^\infty$ I don't find the next step.Help me


How to solve for integral $\int \frac{dx}{\left(x^2+4\right)^2}$

How to solve for:  $\int \frac{dx}{\left(x^2+4\right)^2}$  What I have tried so far:  Let $x = 2 \tan \theta$ so that $dx = 2 \sec^2\theta d\theta$    $I = \int \frac{2 \sec^2 \theta d\theta}{\left(16 \sec^4\theta \right)^2}$  Not sure where to go from here.  The answer that I expect:  $C + \frac{1}{16} tan^{^-1} \frac{x}{2}+\frac{1}{8}x(x^2+4)^{^-1}$


Narration cartoon about a town that has weird paranormal occurrences in it

It's a narration cartoon about a town that has weird paranormal occurrences in it.  It focused on different characters from time to time but the main character narrates an intro and the outro in a lessons learned kind of style.  Main character is a short kid with light blue/greenish skin and darker blue hair.(and if I am not mistaking a Hawaiian shirt).  His friends are a yellowish skater with a baseball cap and 3-d glasses and a slender girl with pinkish skin and purple pigtail hair and a large nose.  It is a western animation (set in North America it seems) and aired on FoxKids/Jetix about over decade ago (in the Netherlands).  An example of an episode is when the skater friend of the main character discovers he has a guardian angel who is in love with him, feeling invincible he becomes more and more reckless and the guardian angel becomes more protective restricting his freedom (don't remember how it ended).  It was an okay show, nothing special but it has been bugging me for weeks that I can't remember the name.


Position of question mark after a quotation (that is not itself a question) and a citation

In British English, where should one place the question mark in the following sentence?  Was it true that "the food was all gone" (Bloggs, 2013, p. 287)  Inside the quotation marks, after them, or even (ugh!) after the brackets? I've come across all three in 'reputable' sources.  Thanks.


How can I determine if a wall is load bearing?

I am doing some renovations on our home and would like to open up some areas but not sure if the walls are load bearing or not I have a three story semidetached home no basement just a crawlspace were furnace is and duck work. also would like to open up stair ways but keep part of walls


What good is the force in a lightsaber duel?

I have watched Star Wars (episodes 4, 5 and 6) and I am curious to know why there is so much importance on mastering the Force. Until now, I have seen the Force being used for pushing, raising heavy objects and pulling (and occasionally strangulating people!) but I fail to see how that helps one wield the lightsaber.  So, how does the Force help one in a lightsaber duel?


Are points in Elliptic curve uniformly distributed?

I need to find an isolated point in an elliptic curve that has the farthest distance from other points.  For example, if we take an elliptic curve $E_{13}(a,b)$, then according to Hasse's theorem, the possible number of points $\#E(p)$ lies between $(13+1-\sqrt(13),13+1+\sqrt(13)) \approx (11,17)$. Considering the worst case, we take $\#E(13)=11$. One of the points is $(0,0)...1^{st} point$. Since elliptic curve points often come in pairs let us take the other points as   $(1,y_1)...2^{nd} point;$  $(1,13-y_1)...3^{rd} point;$  $(2,y_2);...4^{th} point;$  $(2,13-y_2);...5^{th} point;$  $(3,y_3);...6^{th} point;$   $(3,13-y_3);...7^{th} point;$  $(4,y_4);...8^{th} point;$   $(4,13-y_4)...9^{th} point;$   The remaining two points be $(12,y_5)...10^{th} point;$   $(12,13-y_5)...11^{th} point$.  In the recent experiments I have performed, I have found no such curve where a cluster of points exist farthest away from an isolated point pair.  My question: Is there an Elliptic Curve that exhibits such a characteristic ?   OR   Are points in an elliptic curve always uniformly distributed ?


How can i set particle system resolution more 50?  Paticle system must be: emit - volume and grid  Please help!


Suppose we have Lie algebra $\mathfrak{g}$ with basis $t_a$ with a representation $$ t_a \mapsto K_a: V \to V. $$ Denote by $c^a$ the dual basis. Chevalley differential is defined as $$ Q = c^i K_i - \frac{1}{2} f_{ab}^c c^a c^b \frac{\partial}{\partial c^c}. $$ If I try to write BRST transformation for the theory of free relativistic point, $\mathfrak{g}$ will be the algebra of vector fields on the line, which is infinite-dimensional. I don't want to compute structure constants in some basis. Note that the first part of the differential is the action of geberal odd element of the Lie algebra $v = c^i t_i$. Its square is  $$ v^2 = c^i t_i c^j t_j = \frac{1}{2} c^i c^j f_{ij}^k t_k. $$ Than to compute the action of $Q$ to $c$-ghost we should take the square of the universal odd element with minus sign. In the case of the relativistic particle the universal odd element is  $$ v = c(t) \frac{d}{dt}, $$ its square is $$ v^2 = c \dot c \frac{d}{dt}. $$ Then we get $$ Q X = c \dot X, Qc = -c \dot c, $$ but the sign is wrong. I can't figure out mistake. This $Q$ is not nilpotent. Are there other ways to copmute BRST-transformation not introducing the basis of the Lie algebra?


Predicative Position of Adjectives: Do We Hyphenate after the Verb?

Do the words in the following sentences get hyphenated?   She is old-fashioned. He was ill-at-ease. He is well-informed, well-read, well-educated, and well-known. He brought me up-to-date. (Adverbial.) He is up-to-date. (Adjectival.) Joe said, "The test is multiple-choice and fill-in-the-blank." The technology is state-of-the-art and the new software is cutting-edge.


Have the Linux kernel bugs that caused data loss when using a Samsung 850 Pro SSD been resolved?

I just got a brand new Samsung 850 Pro SSD, and I would like to install Ubuntu 14.04 onto it.  I have read some pretty ugly stories of data loss with the 850 series SSDs when using Linux due to bugs in the kernel, as well as bugs in the TRIM operation.  I have done my research, but most of what I'm finding is very outdated. For example, see , and , as well as .  My question is, what is the current status? Have all major the bugs been worked out yet?


Google Search Console reports increase in Soft 404's

I received an alert this morning from Google Search Console reporting that there has been a sharp increase in "Soft 404's". Here is an example of the url that is triggering the 404:  search/%E5%A4%A7%E5%A5%96%E5%A8%B1%E4%B9%90%E6%80%8E%E4%B9%88%E4%B8%8B%E8%BD%BD%E4%B8%8D%E4%BA%86+Q82019309.com.com/   Which is reportedly linked from here:  https://www.example.com/?s=%E5%A4%A7%E5%A5%96%E5%A8%B1%E4%B9%90%E6%80%8E%E4%B9%88%E4%B8%8B%E8%BD%BD%E4%B8%8D%E4%BA%86+Q82019309.com.com   I'm confused by what could be triggering this? It seems like a bot would be doing something like this but why would Google be reporting this as a Soft 404 when it really doesn't exist anyway?


How can i add new elements to generated elements with jQuery?

I was able to generate a new
 to another
 and those new
 have a custom id generated by a counter, i need the code to be able to add new
 to those that where generated.  Code :
     <button type="button" ID="BtnAdd" class="btn btn-basic">Add</button>     <button type="button" ID="BtnRev" class="btn btn-danger">Remove last step</button>
     Title:      <input type="text" id="StepTitle" class="form-control" placeholder="Title..." />     Description:      <textarea rows="5" id="Description" class="form-control"></textarea>

This is how the steps will look like:

   I've tried this:  $("#" + "Btn" + counter).click(function () { $("#" + "div" + counter).append("

" + counter + ". " + StepTitle.value + "

" + Description.value + "
<button type='button' ID='Btn" + counter + "' class='btn btn - basic'>Add</button>
"); });   But it's not working, the expected output should be several
 within themselves all of them generated by jquery, if you guys have any other methods i'll be more than glad to check them out, thanks in advance!


Are $\mathbb{Q}$ or $\mathbb{Z}$ flat modules?

I have the following three question about flat modules.   Why is not $\mathbb{Z}$ a flat $\mathbb{Z}$-module. Why is $\mathbb{Q}$ a flat module $\mathbb{Z}$-module. I need an example of a module which is not flat, nor injective, nor projective.    Thanks a lot!   Note:  I need only a hint to attack those problems not the complete answer.


Convert "ção" and other portuguese characters into proper characters

The following code is returning:   pontuaÃ§Ã£o   I'd like it to return:  pontuação   Code:  $msg = texto("pontuação"); echo $msg;  function texto($string){     return mb_convert_encoding($string, 'utf-8', 'iso-8859-1'); }   Can someone please help with this?


Intuition behind (statistical) completeness

I was wondering if any of the members of this community would like to share his/her intuition about completeness in statistics. For the sake of "completeness", here's the definition, taken from :  Consider a random variable $X$ whose probability distribution belongs to a parametric family of probability distributions $P_\theta$ parametrized by $\theta$. The statistic $T$ is said to be complete for the distribution of $X$ if for every measurable function $g$ (which must be independent of $\theta$) the following implication holds: $$E(g(T(X))) = 0 \mbox{ for all }\theta \mbox{ implies that }P_\theta(g(T(X)) = 0) = 1\mbox{ for all }\theta.$$  Now, to give you an idea of what kind of answer I am looking for, here's how I think about (minimal) sufficiency: I think of a statistic as a partition of the sample space. In that context, a statistic is sufficient for $\theta$ if this partition does not result in a loss of "information" about $\theta$; it is minimal sufficient if it is the coarsest partition which does not result in a loss of information (superlatives carry a uniqueness connotation, which I am ignoring here). Note: I am aware that a  has been asked before, but I'm looking for a different answer.


Policy regarding questions related to unethical or "shady" practices

I recently saw a question on Stack Overflow relating to the . The guy wasn't asking for code at all, meerly asking what the process involved.  It was immediately slapped with a comment directing him to the  (which after reading I still couldn't see why the asker was being directed there), and closed shortly thereafter as "Not a real question".  Since I asked this question, it has been suggested that the question was closed because the asker was asing whether he could ask a question, or because he may have been asking how to unlock his iPhone, where I assumed he was asking for the technical specifics of what happened. Both fair points, it may have been my mistake  As Brad has stated the question  received a very positive response. Another relevant question suggested by Brad, but received a negative response:   Now I know some people out there want to be the Stack Overflow Police, and some people are scared of questions that slightly hint at subversive or underhand methods, or that the asker is trying to do something illegal (either for the sake of the site, or for maintaining their own halos).  However in my opinion it is perfectly acceptable to ask about processes and methods, even in the areas of reverse engineering and programming practicies that are invariably used to exploit other software. Questions like "How do I crack software X?" are obviously unacceptable.  I'd like to know what the community thinks about this; what is your opinion?  Is it ok to ask about shady practices, for educational purposes, as long as they are non-specific (in terms of cacking a certain piece of software, or asking for code to unlock iPhones, etc.)


Given a string $S$,How many different strings can be formed if you are allowed to do   1. at most one swap  2. at most two swaps  By swap I mean interchange characters at two different positions in the string.  All I could figure out is that if $S$ has all unique characters , answer would be $^nC_2$ where $n$ is the length of $S$.


How do stock trades actually go through?

I am trying to get a handle on how stock trades actually go through practically. Let's assume a stock with only one buyer and one seller to make things easier to understand.  Scenario 1: Alice has an ASK price of $10.00 and Bob has a BID price of $9.00. Scenario 2: Alice has an ASK price of $9.50 and Bob has a BID price of $9.50. Scenario 3: Alice has an ASK price of $9.00 and Bob has a BID price of $10.00.  In scenario 1, the trade obviously doesn't happen, because they aren't compatible. The seller wants more than the buyer is willing to pay.  In scenario 2, the trade goes through because it's a match made in heaven.  In scenario 3, I am confused. I'd like to think the trade goes through, because why wouldn't it? But at what price does the trade happen? At the seller's price? Or the buyer's? Or does the stock get sold at the ASK price and bought at the BID price and the difference goes somewhere?  I wish to understand how scenario 3 works. And in general, I want to understand if I am thinking about this correctly. How do trades happen? How do buyers and sellers get matched with each other?


Is 20 dollars here a direct object or a predicate complement? 'This book cost me 20 dollars.'

In this sentence:     This book cost me 20 dollars.   Is 20 dollars a direct object or a predicative complement?


Story about aliens that swap out Earth's government and improve quality of life

I am trying to find a short story about aliens that take over the world's government. The premise is that humanity finds a species at a similar level of technological development. Earth's fleet takes off to fight, but simply disappears, while the alien fleet takes over the world (peacefully, since no one is around to protest). The government is benevolent, and the quality of life on Earth increases dramatically. It turns out that Earth's fleet had performed a similar operation on the alien planet. Both organizations seek highly motivated and idealistic individuals to replenish their ranks and perpetrate the ruse.  The story is told from the point of view of one such highly motivated candidate. He was brain-washed to believe that he belongs to an anti-alien insurgency, and discovers the truth throughout the story. His companion is an alien female, whom he has to transport somewhere in secrecy. Throughout the story, he meets common people that pretty much unilaterally support the new overlords, and realizes that the insurgents are in the minority, but tolerated/manipulated as a necessary evil.  One of the minor plot points is the construction of a highway around the entire globe, that was shown to have created gainful employment for a significant portion of the population, and made travel and trade that much easier for the general population.  The aliens as described as nearly human, but with blue skin. At least the females have partially shape-shifting ability.  I don't remember the exact format of the story (novel, novella or short story). I read it in an anthology some time within the last 10 years, but the story could be much older.


Systems of equations with a single number

I want to write a numbered system of equations. Right now, this is what I do and I am satisfied with the output, but I have a feeling it's not the best way to do it.  \begin{equation}   \begin{array}{ccl}     a + b + c & = & d \\     e + f     & = & g \\     h         & = & i   \end{array} \end{equation}   How should I handle system of equations with a single number associated to it?  UPDATE :  I have read the  and I feel more comfortable with what it offers. However, are there still some situations in which using the array environment is still relevant. For example, I would not know how to produce this result otherwise :  \begin{equation}   \left\{   \begin{array}{lcl}     x_1 + x_2 + x_3 & = & 1 \\     x_1 + x_2       & = & 2 \\     x_1             & = & 3   \end{array}   \right. \end{equation}   In the case the spacing seems correct, and it would not bee desirable to have the first column aligned to the = sign.


Does the OP get notified when I place a bounty on their question?

Nobody's ever posted a bounty on any of my questions, so I have no idea. *  I did try searching for a dupe, didn't find anything.  I just started a bounty on someone else's question. Were they notified about it?  * = Plot twist: What if they have, and I just didn't notice? Depends on the answer to this question.


SQL LEFT JOIN: difference between WHERE and condition inside AND

What's the difference between   select t.*, a.age from t left join a on t.ID = a.ID and a.column > 10   and  select t.*, a.age from t left join a on t.ID = a.ID where a.column > 10   ? Specifically, what's the difference when I put the condition on the table I am joining to the main table inside AND versus inside WHERE condition?


How to install the add-on to import Rhino .3dm files

This question/answer seems exactly what I need.  But I tried installing import_3dm-master.zip as it suggests, and the rhino3dm-master.zip on which it seems to depend (downloaded zips from GitHub) and don't see a new import format on the File->Import list. What simple, obvious thing am I missing? (And I can't just add a comment to that thread because I just signed up and apparently need a 50 to comment. Hmmm.)


What's the General Expression For Probability of a Failed Gift Exchange Draw

My family does a gift exchange every year at Christmas. There are five couples and we draw names from a hat. If a person draws their own name, or the name of their spouse, all the names go back in a hat and we re-draw names. This happens maybe 7 times out of 8.  Using a computer, I know that the probability of this happening is   1 - (440192 / 10!)   or about 88%.  (It's been too long since I took combinatorics) What's a general expression for n couples?  Edit Oct 19, 2011: I was so impressed with the answer, I wrote a blog post about it:


CROSS JOIN and updatable model design for Ruby on Rails

I am trying to build the multi-level model in rub on rails to allow the following to happen: When a user creates a campaign they will select some categories and some metros from tables Category and Metro. Those selections will then be placed within two tables as campaign_category and campaign_metro. But upon the creation of those entries I wish for then another table to be populated with the permutation of those combinations within that table or a series of tables to allow for linking the campaign, the category and metros selected for a user to set a bid price on.  For example say a user creates a campaign that has id 10 and selects category with id 1 and 2, and metros with id 3 and 4. In the tables campaign_category appears:    and in table campaign_metro appears:     How can I allow for the third level table (or series of tables) to be populated with the total permutations of selected category and metro upon the creation of a campaign and also work with ruby on rails active record constructs?


$|e^a-e^b| \leq |a-b|$ for complex numbers with non-positive real parts

Came across this problem on an old qualifying exam: Let $a$ and $b$ be complex numbers whose real parts are negative or 0. Prove the inequality $|e^a-e^b| \leq |a-b|$.  If $f(z)=e^z$ and $z=x+iy$, then $|f'(z)|=e^x\leq 1$ given that $x \leq 0$. I played around with the limit definition of the derivative, but wasn't able to get anywhere. Not sure what else to try; a hint would be very helpful!


Prove a result on transitive group actions.

Let $G$ be a group and $A$ & $B$ be two sets s.t. $G$ acts transitively on each of $A$ & $B$. Choose some $\alpha$ and $\beta$ in $A$ & $B$ respectively then prove that if $G=G_\alpha G_\beta$ then $G=G_x G_y$ for all $x$ $\in A$ & $y$ $\in B$   where $G_x$ is stabilizer of $x$ in $G$ and similarly $G_\alpha$ be the stabilizer of $\alpha$ and $G_y$ is the stabilizer of $y$.  I know we have to choose some elements and apply some manipulative trick. it is hardly 2 liner but just can't think of right elements. help!


According to the , there are four main kinds of galaxies:   Spirals - as the name implies, these look like huge spinning spirals with curved "arms" branching out Ellipticals - look like a big disk of stars and other matter Lenticulars - those that are somewhere in between the above two Irregulars - galaxies that lack any sort of defined shape or form; pretty much everything else   Now, from what I can tell, these all appear to be 2D, that is, each galaxy's shape appears to be confined within some sort of invisible plane. But why couldn't a galaxy take a more 3D form?  So why aren't there spherical galaxies (ie: the stars and other objects are distributed within a 3D sphere, more or less even across all axes)? Or if there are, why aren't they more common?


What free/open source image design programs can you recommend?

Are there any free/ open source image designing programs that you can recommend?


Prove $\frac{1}{f(x)}$ is Riemann integrable

If $f(x)$ is Riemann integrable on $[a, b]$ and  [$\forall x \in [a, b] \  f(x) \ne 0 \land \frac{1}{f(x)}$ is bounded]  then prove $\frac{1}{f(x)}$ is Riemann integrable on $[a, b]$.  I am thinking:  Since $f(x)$ and $\frac{1}{f(x)}$ are bounded, $\exists M \gt 0 s.t. |f(x)| \lt M \land \frac{1}{|f(x)|} \lt M$  Therefore $\frac{1}{M} \leq |f(x)| \leq M$. $\left| \frac{1}{f(x)}-\frac{1}{f(y)} \right|= \left| \frac{f(y)-f(x)}{f(x)f(y)} \right| \leq M^2 |f(y)-f(x)| \ \ (x, y \in [a, b])$ but I don't know what to do.


What is wrong with my Opera installing ? - Public key not available - 16.04

I don't really know what to try.    From the error message it looks like the Opera source is simply missing a signature and to me that means I should not try to use the file because I need to trust Opera when I use it.  If I can do something to refresh or fix the information on my computer about the public key it could solve the problem I think.  sudo apt update Hit:1 http://us.archive.ubuntu.com/ubuntu xenial InRelease Get:2 http://us.archive.ubuntu.com/ubuntu xenial-updates InRelease [102 kB]                    Hit:3 http://ppa.launchpad.net/ondrej/php/ubuntu xenial InRelease                                        Get:4 http://security.ubuntu.com/ubuntu xenial-security InRelease [102 kB]                                 Hit:5 http://ppa.launchpad.net/webupd8team/java/ubuntu xenial InRelease                                              Get:6 http://us.archive.ubuntu.com/ubuntu xenial-backports InRelease [102 kB]                   Get:7 https://deb.opera.com/opera-stable stable InRelease [2,592 B]                           Err:7 https://deb.opera.com/opera-stable stable InRelease   The following signatures couldn't be verified because the public key is not available: NO_PUBKEY D615560BA5C7FF72 Fetched 309 kB in 1s (276 kB/s) Reading package lists... Done Building dependency tree        Reading state information... Done 1 package can be upgraded. Run 'apt list --upgradable' to see it. W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://deb.opera.com/opera-stable stable InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY D615560BA5C7FF72 W: Failed to fetch https://deb.opera.com/opera-stable/dists/stable/InRelease  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY D615560BA5C7FF72 W: Some index files failed to download. They have been ignored, or old ones used instead.


Should I accept wrong answers to boost my accept rate?

I have posted questions on SO for which I have received answers that do not answer the question. No correct answers were offered (I guess I have really good questions ;) )  People tell me my accept rate is low, making my questions less attractive for answering.  Should I accept the wrong ones to boost my accept rate? Is there another option? Can I mark an answer as wrong?


How would I make a network protocol for my 2D game in java?

I have recently made a 2d game in java and need help with making a network protocol that works. I am currently using DataOutputStream and DataInputStream with Sockets and ServerSocket. The Joining is working but the communication between the client and the server is not working. The way I want to have it work and the way i have it set up is so the server does the running and updating and the client receives the position info and data and renders the game and sends back control inputs for the player on the server.   Process:   server: starts client: starts and sends username to the server  server: replies with a UID witch is used to identify the        client and is assigned to the player that is the client  client: sends inputs to server and server receives them        updates the player and sends the data and position info        to the client client: reconstructs the data to a player and renders it (repeat last 2 steps)   This is what I have currently for the reading and writing functions    What I am looking for is suggestions of things I could do or Ideas to try. Thanks


Why are votes locked after a period of time?

I upvoted an answer a while ago, but I realized it was not a good answer. The system does not allow me to take it away, but it allows me to upvote answers long after I have seen it. Shouldn't I be able to unupvote if I'm allowed to vote?


"This is a beautiful pants" or "This are beautiful pants"?

How should I refer to things that are necessarily to be in pair but they are as one, such as pants, trousers, tweezers, scissors, glasses? Should I refer them as singular or as plural in the sentences as follow:      "This is a beautiful pants"      "This are beautiful pants"?      This is the best tweezers that you can have.      These are the best tweezers that you can have.      It is a nice glasses.      They are nice glasses.


This seems a bit odd! I did a program which required me removing duplicated from the list and choose the second last number. I did it using set(). however I came up with something unexpected. set([32.0,36.0,39.0,40.0])  gives me an output of [32.0, 40.0, 36.0, 39.0]. I want to know why this happens. I'm using python 3.9.1 Thanks in advance


Monitors that share the same model yet produce different colors

How could these 2 screens have the settings and are the same model, yet the colors are extremely different and the difference between blue links and purple links is not clear in the one in the right?


Are Stack Overflow mods spending enough time evaluating each flag?

This question arises from a few off-hand comments I have been seeing lately that there is an impression about the Stack Overflow mods that they are so buried in a sea of flags that they don't take the time to properly evaluate each question or answer that gets flagged.  In particular, there seems to be an impression that mods should be doing more work that I personally feel belongs more properly to the community, such as cleaning up spelling errors in posts, or fixing them instead of closing.  I also see signs that the community expects, for example, mods to evaluate a post in its entirety before deleting an answer that has been flagged "Not an Answer," or to provide a pinpoint ruling on the correct use of that flag, rather than focus on whether the answer actually provides any benefit.  Is my perception correct?  Can (or should) the mods be evaluating these decisions more closely than they are?  Could the thought process be improved?  If so, how?    For some references to what I am talking about, see here:


Product of two i)non-differentiable functions and ii)differentiable functions in Complex plane.

Is the product of two non-differentiable functions in $\mathbb{C}$ always non-differentiable ? similarly for differentiable functions ? and if $f$ is not differentiable in $\mathbb{C}$ does that imply that $f$ will always be differentiable in $\mathbb{R}$ ? If Yes , how should i approach this ?


Where can we ask encoding-related questions which are not related to security or encryption?

I want to ask a question, related to encoding for machine learning. I tried on the encryption Stack Exchange site, but it was not related to encryption.  So where should I ask such a question?


Emails sent via Amazon SES going to spam in Gmail

Firstly I have read this question  -- I'm verified on Amazon SES and have DKIM enabled.  I'm sending emails via Amazon SES - on Worpdress (using a plugin MyMail).  I have for the past year been sending weekly newsletters which have been working fine, no problem.   For the past month I have been sending daily automated emails to subscribers (who have double opted in) who have asked for betting tips (horseracing). Each day these tips are generated from my clients database. The email consists of four tips and then links to betting pages on my clients site. There is an unsubscribe button on all emails.  I have noticed in the past few days that Google is sending to spam all emails coming from this domain whether it be a weekly newsletter or these daily betting tips. This wasn't happening before I started sending the daily automated emails. My emails stats haven't changed too drastically though but I presume that's cause most of the receivers aren't using Gmail.  My open rate is about 20% and the click rate about 50%. I realise the terms 'betting' and 'tips' probably flag as spammy but all of my subscribers asked specifically to be on this list.  How I can address this problem? Am I stuck between a rock and hard place owing to the nature of the content - betting and tips  Bearing in mind the subscribers want these daily tips, they signed up for them. I get the feeling these daily emails (not the weekly newsletter) are damaging the website domains reputation.  I'd appreciate any advice on how to approach this situation?


Same gravatar is displayed for different users in stackexchange.com filters

Same gravatar is displayed for different users in the stackexchange.com , under the Top Network Askers in the right side bar.   The red circled image's source (<img src=) are from   https://www.gravatar.com/avatar/?s=18&d=identicon&r=PG&s=30                                ^   Seems the gravatar id is missing here in the image source.  For an example from the list, the user  gravatar id should be    https://www.gravatar.com/avatar/66c66c4d97a7bc3859a85253f003e1fb?s=18&d=identicon&r=PG&s=30   but it is mapped with   https://www.gravatar.com/avatar/?s=18&d=identicon&r=PG&s=30   which caused the display issue.


OK, I'm really confused. I run an Apache 2.2 website on a Mac 10.8.5, and have been doing so for years. I inspect the logs regularly, and I'm careful about service denial in my .htaccess to parties that aren't friendly.   So my logs list IPs. Every once in a while, the log oddly lists a hostname instead of an IP. No big deal. As of the other day, this has changed, for no apparent reason. Now, the majority of my log entries show hostnames, and a few just show IPs. So my system is working hard to look up hostnames for almost everyone!  So I go look in /etc/Apache2/extra/httpd-default.conf, where I find the default   HostnameLookups Off   I go looking around in other conf files to see where there might be a rogue HostnameLookup command, but find none.   So what's is going on? Why is my system looking up hostnames when I'm telling it not to? More to the point, why has it suddenly started doing that? I have not installed any third-party crap, nor have I been doing anything in my conf files. I restarted Apache and rebooted the machine, to no avail.   Now, interestingly, I get several log lines with host names, followed immediately by log lines with just the IP for that hostname. So it's not as if it can't get an IP for that hostname. It just suddenly decides not to.


Include an image in itemize in a beamer presentation

I have to do a presentation with beamer. In a frame I want to insert an image as a object in itemize, so in the first step is only visible the writings, while in the second step the image appears. Here is my code:  \documentclass{beamer} \usepackage[italian,english]{babel} \usepackage[latin1]{inputenc} \usepackage[T1]{fontenc} \usepackage{amsmath} \usepackage{ragged2e} \usepackage{media9}  \begin{document}  \begin{frame} \frametitle{Key Variables in the \textit{Bubble} Phenomena} \begin{itemize} \setbeamercovered{transparent} \item[]<1-> The mean value $\bar{\beta}_{i,t}$ of the intensity parameter is crucial for the development of the synchronization phase, hence it also affects the production volume: %\vspace{0.1cm} \begin{center} \item[]<2-> {\includegraphics[width=.45\textwidth]{gdp_betaC}} \end{center} \end{itemize} \vspace{2cm} \end{frame}   I don't know why, but if I use itemize with different writings as steps the code works, but if I include the image in the second step, the latter appears together with the first one.


"All of them, that is, but Storm."  Is the above line a sentence fragment, and if so, why?  Thanks.


Why does my daily reviews count go up and down depending on the amount of outstanding reviews?

On some sites such as SO, it may happen that for specific review queues there are hundreds (thousands?) of outstanding reviews. For such queues, users may be allowed to perform up to 40 (instead of 20) reviews on a single day. Here is a sample of some of those queues (as shown to me on the /review page today):  ... 2.2k posts (First posts): Thank you for reviewing 40 first posts today; come back in 8 hours to continue reviewing. 139 posts (Late answers): Thank you for reviewing 40 late answers today; come back in 8 hours to continue reviewing. 131 posts (Low quality posts): Thank you for reviewing 20 low quality posts today; come back in 8 hours to continue reviewing. ...  And even though you cannot tell from the above sample, for all these 3 queues, I already performed 40 reviews. So for the low quality posts queue, the number is actually 40, and not 20. At first I thought "hm, this might be some caching issue or something, give it some time and it'll probably show as 40 instead of 20 also". However, that does not appear to be the case. Instead, what seems to happen is:  If the number of outstanding reviews (like the 131) increases enough, e.g. to somewhere around 150 or so, then the 20 will become 40 as well.  If the number of outstanding reviews (like the 131) does not increase anymore that day, i.e. it always remains 131 or less, then the 20 will never become 40.  If the number of outstanding reviews (like the 139 for the Late answers) goes down enough again (say to somewhere below 100 or so), then the 40 (for Late answers) will become 20 again.   My question: what's going on here, is this the intended design? If so: what is the actual design? Or is it some undocumented feature (aka bug)? Update: On Apr 18, 2021 (early morning, before performing any Low quality posts reviews, the number of outstanding reviews was 156. After I completed 40 reviews there were 111 outstanding reviews, and at that point this is what was (correctly) shown:  111 posts (Low quality posts): Thank you for reviewing 40 first posts today; come back in 15 hours to continue reviewing.  However, about 5 hours later, without me performing any additional reviews (since I had reached my daily limit of 40 about 5 hours before), this is what was shown:  109 posts (Low quality posts): Thank you for reviewing 20 first posts today; come back in 15 hours to continue reviewing.  That 20 is wrong, it was already 40 since about 5 hours ago ... Notes:   is not a duplicate question, e.g. because the (accepted) answer to it states “... after 20 reviews in a given queue*, you're done for the day ...”, which is clearly not what my question is about.  is not a duplicate question either, e.g. because the (accepted) answer to it explains (within the reviews part of it) what the maximum number of reviews for a given queue is, while my question is about the mismatch between the number (40 or 20) as shown, as compared to the correct number (it is actually 40 for each of the 3 queues).


The space $c_0$ of sequences that converge to 0 is not reflexive

Consider the Banach space $X$ of null sequence whose elements are complex sequence which converges to $0$. In addition the norm is defined as $$\|(a_1, \dots, a_n)\| := \sup_n |a_n|.$$ Show this space is NOT reflexive. Recall that the dual of $X$ is $l_1$. Also use the following fact. If $X$ is reflexive space and $(x_n)$ is a sequence in $X$ and for all $\psi \in X^*$, the sequence $\psi(x_n)$ has a limit in $\mathbb C$, then $x_n$ converges weakly to some $x \in X$.   Suppose that $X$ is reflexive. Consider the sequence $$u_n = (1, \dots, 1, 0, \dots) \in X,$$ where first $n$ entries are $1$. Then for any $y \in l_1$, we have $$y(u_n) := \sum_n y_n\times u_n = y_1+\dots+y_n \to \sum_n y_n < \infty,$$ since $y$ is absolutely convergent. Now it is only left to show that $u_n$ does not converges weakly to some $u \in X$ which I guess is $(1, 1, \dots)$. That is, for all $y \in l_1$, $$y(u_n) \nrightarrow y(u).$$ However, this seems correct to me. Where did I make mistake, please? Thank you!


I am trying to have a label with the text "I(X;Y)". However, it fails to compile due to the semicolon. Is there any way to escape the semicolon?  Edit: The following code works perfectly  \documentclass[tikz,border=3.14mm]{standalone}  \begin{document}  \begin{tikzpicture} \node at (0,0){$I(X;Y)$}; \end{tikzpicture} \end{document}   However, in my document I had \usepackage{breqn} and compilation does not complete when used with it.  \documentclass[tikz,border=3.14mm]{standalone} \usepackage{breqn}  \begin{document}  \begin{tikzpicture} \node at (0,0){$I(X;Y)$}; \end{tikzpicture} \end{document}


Why can a set of random variables be called a sample?

I am trying to understand this slide on sample means. I understand the meaning of the word sample  as if grabbing a handful of jellybeans from a packet. Yet in this slide, when the jellybeans are themselves random variables, why is it called a sample? The slide does not state that it is talking about a "Random Sample" Should it?


I'm looking for a list of nearly all elements and the temperatures they can reach when in a state of plasma. It is for a project I am working on. However, there isn't a list on google.  Preferably one that is hot enough to survive a drop from orbit.


How do I get the boot manager to give me an option to choose from which os I want to boot?

I have a computer in which Windows 10 is installed.Recently I have installed  Ubuntu on it.The boot manager automatically boots my computer with Windows.Now I want the boot manager to give me a boot menu each time I login automatically so I can choose from which OS I want to boot my computer.How can I do that? My computer has Ubuntu and Windows on it.


Is a merge supposed to be able to yield the Necromancy badge?

I'm pretty sure that when I posted , the question was very different and fairly recent, which makes me suspect a .  However, I just got  for that answer.  Is the Necromancer badge supposed to be given when an answer "with score of 5 or more"  gets merged from a recent question to a question that is "more than 60 days" old?


Remote Desktop connection starts up, screen draws, then goes black

Sometimes when I remote into my computer, I can get in and see everything and drive the mouse for a few seconds -- then the screen goes black and just sits there.   Anyone seen this before and know the reason or how to fix?


Java - How to check if a abstract superclass is a particular subclass

The question might look trivial but I couldn't find the solution anywhere!  I have an abstract superclass Vehicle, and there are 4 subclasses that extend it, viz Car, Bus, Lorry and Bicycle.  I also have an ArrayList<Vehicle> V containing many Vehicle objects but we don't know which type of vehicle.  Now I am not able to calculate the number of Cars in the ArrayList V  int carCount = 0; for (Vehicle ob: V){     if (ob is a car) {         carCount++;         }     } return carCount;   Would like to know what should be the code inside if(ob is a car) in the code above.  Thanks!


How to tighten up mesh before subsurface mod added

I'm modelling this detail and when I add the subsurface mod, it does odd things.  I cant make any loop cuts on it for some reason so have to use the knife tool.  Would I have to add alot of cuts to be able to get a clean looking mesh... any help on where to make cuts without creating ngons?


htcacheclean doesn't seem to be cleaning the cache

I'm running mod_cache with apache 2 on a fairly high traffic'd site.  I've set the htcacheclean to run in demon mode every 10 minutes to keep the cache at 4GB. It's currently at 15GB and doesn't seem to be shrinking.  When I call htcacheclean manually it hangs for (at time of writing) 40 minutes.  Some preliminary research turned up this question     said that I should ensure index_dir is on, which it seems to be  # tune2fs -l /dev/sda3 | grep dir_index Filesystem features:      has_journal ext_attr resize_inode dir_index filetype needs_recovery extent flex_bg sparse_super large_file huge_file uninit_bg dir_nlink extra_isize   Are there other settings that I can turn on / ensure are turned on to help htcacheclean keep up with the cache generation?


Difference between Differentia and Quality

No matter how many ways I think of it - just how Socrates is a Man, any differentia is a Quality. So for eg, one much used example is 'rational' - man is a rational animal, where man is species, animal the genus and rational a differentia. Isn't rational a Quality? Doesn't it come under the category of Quality?


After a few days why does my hot sauce separate leaving liquid in the bottom?

After making my hot sauce it tends to separate leaving a vinegar at the bottom and sauce at the top. When I shake it up then it's back to normal. Any suggestions?


Is it possible to book return but travel oneway?

It seems like one-way tickets are always more expensive than buying round-trip. So I am planning to book a return ticket. For example I would like to go on the following itinerary this May. Myself & my friend are planning to travel.  I have a valid visa for Malaysia and I am going to Vizag on May22nd using another itinerary and will return using below itinerary ( May 28th )   May 12th - Malaysia --> Vizag  ( wont do journey ) May 28th - Vizag    --> Malaysia ( will do journey)   My friend did not visit Malaysia yet, but if I booked below itinerary for him, could he do only the one way journey on May 28th ?   May 12th - Malaysia --> Vizag  ( wont do journey because never visited before ) May 28th - Vizag    --> Malaysia ( will do journey)


Could we make the Help Centers easier to find?

Every Stack Exchange site has the same six buttons along the top banner:    Questions Tags Users Badges Unanswered Ask Question   I've been a regular on SE some time now, and I've seen countless instances where a new user was exhorted to visit the Help Center, to learn more about site norms, what is on-topic, how to ask a question, etc. I've left some of those comments myself.   As I was doing this for the umpteenth time today, I started wondering: Why isn't a link to the Help Center more prominently displayed? In order for  newcomers to find it, they would need to click on an odd-looking chat bubble icon.     (I realize that a link to the Help Center also shows up once a user clicks the Ask Question button, but, by then, I think most newer users are focused on their question, and not so interested in interrupting their train of thought to go tour the Help Center.)  I also realize this would not be a panacea – we will always have users who will ask questions first, and then learn more about the site later. Still, I wonder if we aren't putting more work on ourselves than necessary by making the Help Center so well-hidden in the first place, particularly since we'd like everyone to read all the material there that explains what makes this place so unique.  Would a seventh button across the top of all the sites be an improvement?  I'd like to find a way to make a link to the Help Center a bit more prominent and easier to find.


How to get information about deb package archive?

How to get information about .deb package archive?   Like: package information, version, installed-size, architecture, description and licensing information etc. from .deb package archive?


Let's say we're trying to give a Giant Ape three-quarters cover from a distant archer. A spellcaster casts Silent Image to place a rock in between them of the right shape and size to cover 3/4 of the Giant Ape in that direction. Does the archer shooting the Giant Ape have to overcome +5 AC from cover? Or does the fact that the illusion is permeable by arrows result in no additional AC?


I have a list with more than 5000 items and this number can change daily (can go up to 10's of thousands). The length of list changes on almost a daily basis. So I want to split the list into smaller lists of length of 300 but I want the name of these smaller lists to be defined dynamically.  I.e.:  main_list = ['1029', '2314', '466754', '6345', '3456' ....]   to  list1 = ['1029', '2314' ... first 300 elements] list2 = ['342343', '3425' ...  next 300 elements]   and so on.


I have a javaScript file in which i am trying to bind a function named change by using jQuery i tried this code but it is not working?   script.js   for(var i=1; i<suggestionList.length; i++)             {                 $list.append("<li>" + suggestionList[i] + "</li>");                 // attach handler for click on the suggestions                 $list.find("li").eq(i).click(function() {                     change(suggestionList[0], suggestionList[i]);                 });             }       function change(changeto,changewith)         {             var replaceto=document.getElementById(changeto).innerHTML;             var replacewith=changewith;             var text1=document.getElementById("para").innerHTML;             var afterRe=text1.replace(replaceto,replacewith);             document.getElementById("para").innerHTML=afterRe;         }   please help me why my code is not working?


Check the empty field validation in visualforce page by using json

I am using some Table! which is  wrapper list, and when i will hit some button and if the values in those fields are blank i need to show a validation message on page with help of json. i am new in salesforce. please provide me solution


Posting a link to a post on 3D Printing site, for example  https://3dprinting.stackexchange.com/q/5736, does not produce a onebox in chat.   I suppose it's because the chat does not expect there could be digits in site names.


Using Thunderbird and gmail, sent items appear as unread in "All Mail"

I'm using a gmail account in Thunderbird. When I send a message, a new mail notification appears (sound and system try icon), an unread message appears in the gmail All Mail folder, and the account name turns blue.  I have to click on "Sent Mail" or "All Mail" to get rid of the notification. Unsubscribing from "All Mail" is not effective (it still turns the account name blue).  This seems to be popping up elsewhere (), but nobody has posted a helpful answer.  How do I keep Thunderbird from thinking that a sent message is new unread mail in the All Mail folder?


Filter messages to one group mailbox and not to a second group mailbox

I am a part of multiple groups in my corporate Gmail account, and would like to filter out all emails from my Inbox that come to group1@gmail.com so that they are marked as read and archived, except when the message is also addressed to group2@gmail.com, in which case I want to keep it in my Inbox.  To summarize:   If a message is addressed only to group1@gmail.com, filter it out of my inbox If a message is addressed only to group2@gmail.com, keep it in the inbox If a message is addressed to both group1@gmail.com and group2@gmail.com, keep it in the inbox.   I tried a lot of filters but somehow could not get it right. Is there a way to achieve this ?


Amount of decimal places and fixing column formating

Here is the problem I have to answer: (Compare loans with various interest rates) Write a program that lets the user enter the loan amount and loan period in number of years and displays the monthly and total payments for each interest rate starting from 5% to 8%, with an increment of 1/8.    import java.util.Scanner; // Scanner is in java.util public class FinancialApp {    public static void main(String[] args) {      Scanner input = new Scanner(System.in); // Scanner object       System.out.print("Enter loan amount: "); // input value for loan       double loanAmount = input.nextDouble();       System.out.print("Enter number of years as an integer: ");       int years = input.nextInt();       System.out.println("Intrest Rate" + "\t" + "Monthly Payment" + "\t" + "Total Payment");       for(double i = 5.000; i <= 8.000; i += 0.125){     double monthlyIntrest = i / 1200;    double monthlyPay = loanAmount * monthlyIntrest / (1 - 1 / Math.pow(1 + monthlyIntrest, years * 12));    double totalPay = monthlyPay * years * 12;     System.out.println(i + "%" + "\t" + monthlyPay + "\t" + totalPay);    }  } }    First off I'd like to say that I'm very inexperienced when it comes to coding and my professor hasn't taught us anything at all, so if it could be explained simply I'd really appreciate it. I'm struggling with this class enough. Ok, to the real problem: The code runs, however, it gives me numbers for monthly payment and total payment that have 6+ decimal points and I have no idea how to get it to 2 decimal places. Also, the numbers for the monthly payment are offset to the left (not lined up with the column label).


Any stock means of inserting a period by pressing the spacebar twice?

I've grown to really appreciate the ability to press space twice on my iOS devices and have a period manually inserted without having to switch keyboards.  Though I realize the need isn't quite there on actual keyboards since the key is accessible at all times, I'm curious: Is there any way to get the same behavior using baked-in functionality on Mac OS X?  This is assuming the most recent version of Mountain Lion is installed.


Why only 3 last rep events shown and no "view more"?

Usually I have this picture (as on my  now). 4 last events and "view more".        But now in  there on Meta only 3 last events and no "view more".        Could anyone explain me why?


Android class member, should I declare protected?

Should I declare an Android class member protected? What would be the benefits? All examples I see just declare the field type and its name ("package protected").  protected TextView mName;   vs   TextView mName;   I don't need to extend such class.


Laptop shuts down when placed on top of another laptop

I can reproduce this 100% reliably. We have two Dell XPS 13 laptops, both running Ubuntu. If one is placed on top of the other (the bottom one is closed, the top one is open), the one on top will shut down. If we restart it, it will shut down again within a minute or two. The two computers are the same model. All it takes to make the shutdown happen is for one computer to be on top of the other—no other action needed. There must be some communication going on between them, but what? And why is the top one shutting down? Any ideas?


I was trying add ones to some specific position in a 100*100 zero matrix. My code was something this:  adjacency=[[0]*100]*100 while ...     x=...     y=...     adjacency[x][y]=adjacency[x][y]+1   But it adds to other positions as well. In face, adjacency[0]=adjacency[1]=..=adjacency[99], while there's no way that the calculation of x, y in while-loop will produce this kind of result.  So, I changed to array. The only thing I changed was:  adjacency=np.zeros((100,100))  And the result is right this time. Adjacency[i] no longer equals to each other.  Does anyone know why? (Using Python2.7.)


Let $A, B\in M_n(\mathbb{C})$ s.t. $AB=BA$. Show that the eigenvalues of $A+B$ is the sum of eigenvalues of $A$ and $B$.   First I tried to find a counterexample and I found out this property without proof.


How can I integrate $\int \frac{\sqrt{\sin x}}{\sqrt{\sin x}+\sqrt{\cos x}}dx\;$?

$$\int \frac{\sqrt{\sin x}}{\sqrt{\sin x}+\sqrt{\cos{x}}}dx$$ Does a closed form exist for this integral? It has withstood every integration technique I know and WA shows an error ("try the following.." etc)


How to find if my hardware supported by Ubuntu?

It is better to let make sure if System can/will be worked effectively & efficiently.  So, before installing Ubuntu, how can I find out if my hardware like motherboard components, graphics card, etc, are supported by Ubuntu?  Can I find through model or chipset or as better as possible?


Huge Wallch icon in Xubuntu 14.04 (xfce-panel)

I have strange problem. My Wallch icon is huge. See the screenshot:    I removed XFCE settings and reordered items a little. How can I restore normal Wallch icon size?  Update:  My /usr/share/applications/wallch-nautilus.desktop file:  [Desktop Entry] Version=4 Name=Wallch Comment=Change desktop wallpapers automatically Exec=/usr/bin/wallch %U Icon=wallch Terminal=false Type=Application Categories=Utility;Application; MimeType=inode/directory;  Actions=Change_Wallpaper;Start;  [Desktop Action Change_Wallpaper] Name=Change Wallpaper Once Exec=/usr/bin/wallch --change TargetEnvironmet=Unity  [Desktop Action Start] Name=Start/Stop Wallpapers Exec=/usr/bin/wallch --start TargetEnvironment=Unity   And the /usr/share/pixmaps/wallch.png:


What's wrong with a new installation of Drupal 8.6.10?

A fresh install of Drupal results in a WSOD including a very helpful error message which says "The website encountered an unexpected error. Please try again later."  I normally install Drupal with the drupal-project template from github and at first, I thought this was a problem with my local DDEV environment. I then tried with MAMP Pro to find exactly the same.   Finally I tried on simplytest.me to realise that it isn't me.  A look at my local error logs reports the following;  "NOTICE: PHP message: Uncaught PHP Exception Twig\Error\SyntaxError:  An exception has been thrown during the compilation of a template  ("Attribute "name" does not exist for Node  Twig\Node\CheckToStringNode) in  core/themes/bartik/templates/block--system-menu-block.html.twig"." at  /var/www/html/public_html/vendor/twig/twig/src/Environment.php line  797"   I found that is was possible to access the site via the admin path, and changing the theme to Stark allowed me to view the site.   I then attempted to view recent system messages at admin/reports/dblog - only to once again to get the "Please try again later" message.


Find the value of $x,y$ for the equation $12x+5y=7$ using number theory .

I tried the solution using other ways like:  $12x+5y=7$  $12x=7-5y$  $x=7-5y/12$  putting the value of $x$  $12(7-5y/12)+5y=7$  both $12$ will cancel out  $7-5y+5y=7$ here comes the problem please help me ?


How to make "open in terminal" in the right click menu use Terminator instead of gnome terminal?

I have set the default terminal emulator to terminator using update-alternatives and I can open terminator now with ctrl-alt-t, but when I use the right click menu on the desktop or in a folder it will open gnome-terminal.   Is there another setting to change to fix this?   I've edited compiz to try the 3d cube effect and from then had to reset compiz to default settings to revert which reset my terminal default. To get ctrl-alt-t working after this I also had to do gsettings set org.gnome.desktop.default-applications.terminal exec 'terminator'. I found this suggestion in  , but this did not make it so the right click option open terminator.  I am using Ubuntu 15.10


Python - Is it possible to generate nodes in a loop?

and make a singly linked list while looping? like so:  def make_nodes(n):     head_node = Node(0,None)     for i in range(1,n):         node("i") = Node(i, None)         #somehow link them    so that the nodes will be named: node1 node2 node3 ... node9  Many thanks in advance!


Rotating ~90° using Two-Point Equidistant projection with Proj4

I'm trying to rotate a tif raster in R using Proj4's  projection - I think the only way to rotate spatial geometries to custom angles.  But I'm finding the operation gets very slow approaching 90°, and in fact fails for that angle (possibly 2 separate issues).  This demonstrates:  require(raster) require(rgdal) # demo raster r <- disaggregate(raster(volcano[1:60,1:60]), 4) extent(r) <- c(-5,5,-5,5) crs(r) <- "+proj=longlat +datum=WGS84"  # proj4 two-point equidistant rotate transformations tpeqd_45 <- CRS("+proj=tpeqd +lat_1=2 +lon_1=-2 +lat_2=-2 +lon_2=2 +a=6371000 +units=m +no_defs") tpeqd_80 <- CRS("+proj=tpeqd +lat_1=1.9 +lon_1=0.35 +lat_2=-1.9 +lon_2=-0.35 +a=6371000 +units=m +no_defs") tpeqd_90 <- CRS("+proj=tpeqd +lat_1=2 +lon_1=0 +lat_2=-2 +lon_2=-0 +a=6371000 +units=m +no_defs")  system.time(r_45 <- projectRaster(r, crs=tpeqd_45))    user  system elapsed    0.350   0.051   0.404  par(mfcol = c(1,2)); image(r, asp=T); image(r_45, asp=T)     system.time(r_80 <- projectRaster(r, crs=tpeqd_80))    user  system elapsed    3.857   0.879   4.877 system.time(r_90 <- projectRaster(r, crs=tpeqd_90)) Error in if (value[1] != nrow(x) | value[2] != ncol(x)) { :    missing value where TRUE/FALSE needed In addition: Warning message: In `dim<-`(`*tmp*`, value = c(nr, nc)) :   NAs introduced by coercion to integer range   Note the increasing time to process for 80°.  For a 10x bigger raster this crashes my Macbook.  Does anyone know if this is a problem in the math for this projection and/or if there is any other way to rotate these in R?


İf $\lim x_{n}=x$ then how to show this equation?

If  $\lim_{n \to \infty} x_{n}=x$ equality is true how to show this equations? $\lim_{n \to \infty}\dfrac {x_{1}+x_{2}+\ldots +x_{n}} {n}=x$


Any difference between "be subject to" and "be subject*ed* to"?

"Children are subject to colds" vs. "Children are subjected to colds" Q. Is there any difference between "be subject to" and "be subjected to"?


Show that $|a-b|<\frac{|b|}{2}$ implies $\frac{|b|}{2}<|a|$

Pretty simple, for $a,b \in \mathbb R$, show that $|a-b|<\frac{|b|}{2}$ implies $\frac{|b|}{2}<|a|$.  I can see this graphically on the number line, but I can't seem to show it algebraically. I'm think it involves the triangle inequalities:  $$|x+y|\le|x|+|y|$$ $$|x-y|\ge||x|-|y||.$$


Empty question and answer view on specific question

I saw on  today, viewing it through the Android app, that the question body, and answers body is missing.   This is the first time I saw this problem.


pgfplots matrix plot "perfect" rectangles

Edit: I removed the duplicate part of the question, which was answered here:  and here:  (Feature Request for PGFplots )  I'm trying to plot a matrix with pgfplots and have three questions one question regarding the following MWE. Should I ask every question separately? Edit: Yes I should have.  \documentclass{standalone} \usepackage{pgfplots} \usetikzlibrary{pgfplots.colormaps} \pgfplotsset{compat=newest}  \usepackage{filecontents} \begin{filecontents}{\jobname.dat} x y C 0 0 32 0 1 0 0 2 0 0 3 0 0 4 0 1 0 0 1 1 16 1 2 0 1 3 0 1 4 0 2 0 0 2 1 0 2 2 16 2 3 0 2 4 0 3 0 0 3 1 0 3 2 0 3 3 16 3 4 0 4 0 0 4 1 0 4 2 0 4 3 0 4 4 16 \end{filecontents}  \begin{document} \begin{tikzpicture} \pgfplotsset{%     colormap={WhiteRedBlack}{%         rgb255=(255,255,255)         rgb255=(255,0,0)         rgb255=(0,0,0)     }, } \begin{axis}[%     small,     every tick label/.append style={font=\tiny},     tick align=outside,     minor tick num=5,     %     xlabel=$\beta$,     xticklabel pos=right,     xlabel near ticks,     xmin=-1, xmax=5,     xtick={0, 5, ..., 4},     %     ylabel=$\alpha$,     ylabel style={rotate=-90},     ymin=-1, ymax=5,     ytick={0, 5, ..., 4},     %     point meta min=0,     point meta max=32,     point meta=explicit,     %     colorbar sampled line,     colormap name=WhiteRedBlack,     scale mode=scale uniformly, ] \draw (axis description cs:0,0) -- (axis description cs:1,0); \addplot[matrix plot, mesh/cols=5] table[meta=C] {\jobname.dat}; \end{axis} \end{tikzpicture} \end{document}    When one zooms into the drawn rectangles, one can see a short line dropping from the left-lower and right-upper corner of the rectangle, so not a "perfect" rectangle is drawn (see screenshot). Can this be fixed?    Regarding the question if this stems from a problem with the PDF viewer: I checked it with Evince, the Firefox PDF viewer, mupdf (here the lines appear) whereas Adobe Acrobat and Okular showed the PDF without these lines..


I want to use 'audience' in the following sentence. In what form should I use it? Is it a singular or plural noun?     How the audience demotivate players in the NBA.      How the audience demotivates players in the NBA.


I was using Euler's formula $ e^{ix} = \cos(x) + i \sin(x)$ with the case when $ x = 2\pi$. $$ e^{i2\pi} = \cos(2\pi) + i\sin(2\pi) = 1 + 0i $$ So I end up with the identity $ e^{i2\pi} = 1$. Now, if I apply $\ln$ it goes $$ \ln e^{i2\pi}=\ln1$$ $$ i2\pi = \ln1$$ How $\ln1=0$, Should be that $i2\pi=0$ its true, or not? The first implication I found its that you can divide any imaginary number by zero. $$ {ai\over 0} = {ai\over i2\pi} = {a\over 2\pi}$$ What don you think?


Shell script to convert the date format in a file

I would like to convert the date format in file, using a shell script.  Input:  S.no|Name|Joining_Date|Address 1|asdasd|09/18/2018|asdas 2|asd|09/18/2018|asdasd 3|asdas|09/18/2018|aadadw   Output:  S.no|Name|Joining_Date|Address 1|asdasd|18/09/2018|asdas 2|asd|18/09/2018|asdasd 3|asdas|18/09/2018|aadadw   Below are the scripts which have tried  Input File: cat datesep.txt  :  asdasd|asdasd|asdasd|30/08/2018|sadasd   asdasd|asdasd|asdasd|12/09/2018|sadasd   asdasd|asdasd|asdasd|23/06/2018|sadasd   asdasd|asdasd|asdasd|26/10/2018|sadasd   asdasd|asdasd|asdasd|23/09/2018|sadasd   asdasd|asdasd|asdasd|12/07/2018|sadasd    cat test.sh    #!/bin/bash   date +'%d-%m-%y'   DATE=`date +%d`   MONTH=`date +%m`   YEAR=`date +%y`   echo "${MONTH}/${DATE}/${YEAR}"     cat test1.sh    #!/bin/bash   SOURCEDATE=`awk -F '|' '{print $4}' /home/work/datesep.txt`   TEMP=$SOURCEDATE   echo $TEMP   DATE=`cut -c 1-2 ${TEMP}`   MONTH=`cut -c 4-5 ${TEMP}`   YEAR=`cut -c 7-10 ${TEMP}`   echo "${MONTH}/${DATE}/${YEAR}"     cat test2.sh    #!/bin/bash   awk -F '|' '{print $4}' /home/work/datesep.txt > /home/work/temp.txt   TEMP=$SOURCEDATE   echo $TEMP   DATE=`cut -c 1-2 /home/work/temp.txt`   MONTH=`cut -c 4-5 /home/work/temp.txt`   YEAR=`cut -c 7-10 /home/work/temp.txt`   echo "${MONTH}/${DATE}/${YEAR}"     cat test3.sh    #!/bin/bash   awk -F '|' '{print $4}' /home/work/datesep.txt > /home/work/temp.txt   TEMP=/home/work/temp.txt   COUNT=`cat ${TEMP} | wc -l`   echo $COUNT   echo $TEMP   LINE_NUM=1   while read LINE   do           DATE=`awk -F '/' '{print $1}' LINE`           MONTH=`awk -F '/' '{print $2}' LINE`           YEAR=`awk -F '/' '{print $3}' LINE`           echo "${MONTH}/${DATE}/${YEAR}"           ((LINE_NUM++))   done < $TEMP    cat test4.sh    #!/bin/bash   awk -F '|' '{print $4}' /home/work/datesep.txt > /home/work/temp.txt   TEMP=`/home/work/temp.txt`     for LOOP in `/home/work/temp.txt `   do           DATE=`awk -F '/' '{print $1}' $LOOP`           MONTH=`awk -F '/' '{print $2}' $LOOP`           YEAR=`awk -F '/' '{print $3}' $LOOP`           echo "${MONTH}/${DATE}/${YEAR}"   done


colouring vertices of cube while considering symmetry

Let $G$ be the rotation group of a cube $Q.$ How many ways (up to symmetry under the action of $G$) can we colour the $8$ vertices of $Q$ using $2$ colours?  I know the Burnside or Cauchy-Frobenius Lemma, which says that for a finite group $G$ that acts on a set $S, |G| |S/G| = \sum_{a\in G}|Fix(a)|,$ where $Fix(a) := \{x \in S : ax = x\}.$ I know there are $24$ elements in $G$. Let $S$ be the number of colourings without considering symmetry. Then $|S| = 2^8.$ The rotation group induces a natural action on the set $S$, but I'm not really sure how to formally describe this action. However, once I can formally describe the $24$ elements of $G$ and then determine their corresponding $Fix$ cardinalities (the corresponding $Fix$ cardinality of element $A\in G$ is $|Fix(A)|$) it should be fine. For instance, $|Fix(I)| = 2^8,$ where $I$ is the identity rotation.  Could someone help me uncover the cardinalities of $Fix(A)$ for $A\in G$?


Java: Easy way of passing a method as a parameter

I'm attempting to create a better logging situation for myself. Currently I'm just custom writing a string and logging that string. What I'd like to do instead is know the exact Class#method combination that I'm logging. Currently I'm writing it out such as:  Logger.push(String s) where s is something like "ClassA#myMethod: Successfully implemented database  What I want to do it make it a little easier on myself, my reducing the text I have to write if possible. I don't want to have to type ClassA#myMethod, instead what I want to do is pass a method and use reflection to get the desired names. Here's the example logger function I've created:  public static void push(String msg, Method cont){     logger.info(cont.getDeclaringClass().getSimpleName() + "#" + cont.getName() + ": " + msg); }   My issue is with passing the method. Ideally I'm looking for something like this, but for the actual method. Currently the only way I could think of is something like:  Logger.push("Hello World", getClass().getDeclaredMethods("thisMethodName");   I was just wondering if there was an easier to get the currently used function. Thanks!


How to preview an Illustrator document at different rasterized sizes?

I'm designing a favicon in Illustrator and I'd like to see what it would look like in pixels at 128px and 16px as I'm working on it.  Is this possible?  Edit Found the answer - posted below.


How do you check the windows version in Win32 at runtime?


I've been messing around with modular arithmetic recently, and stumbled across this, but couldn't find a proof for it anywhere. I hate taking things as truth without knowing why, so could anyone provide a (fairly simple) proof?


During a Cycles render an object behind glass looks striped

Using Cycles I rendered a object inside a tube (it's glass material). The problem is the object edges are striped as shown here:    The same thing happened for another project too:     In the first render I tried different options but the issue is still there. Is there any way to fix this?


Prometheus to Alien: Who is on the crashed spaceship in Alien?

In Prometheus, towards the end the Engineer leaves his spaceship to pursue Dr. Shaw, and we last see him on the floor of the escape pod after an alien pops from his chest. In Alien, when examining the spacecraft, the crew finds the Engineer skeleton inside of a cockpit with a hole in it's side. Isn't this supposed to be the same Engineer that chased Shaw? How is he still in the cockpit?


how to see all network requests made by an application

Suppose i have an application running abc.exe, how to see all the network requests made by this application? Wireshark is good to see all the requests from the pc, but is there any filter for requests from particular application.  The requests made by abc.exe can be of any type, http, https, or just LAN pings. Is there any way to do it apart from seeing all network requests, just for an application.  For example: how we use charles for firefox, like that anything available? Thanks.  EDIT: From using smartsniff i understood that we can't have single requests sent by an application. Only browsers do that, send a request line and get a response. So most applications open an address and port & starts reading/writing from/into it.So how to trace them for an particular application?


How can I make a surface look wet in cycles?

I am trying to recreate a wet road with lights reflecting off of it. I started by making the object glossy but this did not give a very realistic look  I think I need to increase the specularity of the reflection to make it look more real but I can't find this option anywhere in cycles. Also what other techniques can I use to make a surface look wet in blender? I can link directly due to licening but  is what I am trying to recreate.


How to add line numbers to a program listing/code?

How do I copy code in to latex to get a result which looks like this:    ...Without the red bars of course. I don't know how to get the numbering on the left side when I compile LaTeX. Using \verbatim only gives me the code.  Update: Having the code colored as it would appear in Matlab is necessary.


Why does reversing the rules of "an" vs "a" make speech easier at times?

Background From what I’ve learned during grade school, information which can easily be , you should use an when the following word starts with a vowel:  "An animal" "An alien" "An ewok"  And a when the following noun starts with a consonant:  "A car" "A radio" "A xylophone"  Following these rules seem to ease how we pronounce things. If I reversed the rules and tried saying An xylophone, or a alien, I seem to struggle more than if following the rules.  Confusion When pronouncing the acronym LEA, short-hand for Local Educational Agency Representative, myself and my peers would use "an", such as:  "Do you have an LEA?" "An LEA is required for that."  I’m not sure if this is specific to acronyms, since a LEA may be ambiguous:  a LEA ALEA  However, I’ve seen/used acronyms following an a without issue:  a PHP file exists in the system   Question Would saying an LEA be improper? Is there a documented reason for why this rule complicates how we pronounce our words?