I want to create a filtered array with LINQ inside the function I created and print it on the screen. I got some errors.     static void Main(string[] args)     {         //created an integer array         var values = new[] {2,9,5,0,3,7,1,4,8,5 };          // display original values         Console.WriteLine("Orijinal Dizi:");         foreach (var element in values)         {             Console.WriteLine($"{element}");         }          FilteredArray(values);              }     public void FilteredArray(int[] values)     {         var filtered =             from value in values             where value > 4             select value;         Console.WriteLine("4ten büyükleri filtreleyen dizi");         foreach (var item in filtered)         {             Console.WriteLine($"{item}");         }     }  "FilteredArray (values);" is underlined in red. Error CS0120: An object reference is required for the non-static field, method, or property 'Program.FilteredArray(int[])'

Consider:  namespace WindowsApplication1 {     public partial class Form1 : Form     {         public Form1()         {             InitializeComponent();         }          private void button1_Click(object sender, EventArgs e)         {             //int[] val = { 0, 0};             int val;             if (textBox1.Text == "")             {                 MessageBox.Show("Input any no");             }             else             {                 val = Convert.ToInt32(textBox1.Text);                 Thread ot1 = new Thread(new ParameterizedThreadStart(SumData));                 ot1.Start(val);             }         }          private static void ReadData(object state)         {             System.Windows.Forms.Application.Run();         }          void setTextboxText(int result)         {             if (this.InvokeRequired)             {                 this.Invoke(new IntDelegate(SetTextboxTextSafe), new object[] { result });             }             else             {                 SetTextboxTextSafe(result);             }         }          void SetTextboxTextSafe(int result)         {             label1.Text = result.ToString();         }          private static void SumData(object state)         {             int result;             //int[] icount = (int[])state;             int icount = (int)state;              for (int i = icount; i > 0; i--)             {                 result += i;                 System.Threading.Thread.Sleep(1000);             }             setTextboxText(result);         }          delegate void IntDelegate(int result);          private void button2_Click(object sender, EventArgs e)         {             Application.Exit();         }     } }   Why is this error occurring?     An object reference is required for the nonstatic field, method, or property 'WindowsApplication1.Form1.setTextboxText(int)


I am trying to make a paintbrush to assist me and my friends build a city.  My idea for the paintbrush is when held, it uses raycasting to place blocks where the entity is looking.  I can't use scripting because one of my friends is on Xbox and can't use scripting for some reason.  For the raycasting, I'm using a mcfunction.  How do I run a slash command or function when a player holds a specific item in Minecraft bedrock?  I think it's possible because it says in the Minecraft addon documentation entity events can call slash commands, other entity events, and MoLang.  I'm attaching a picture of that section of the documentation so you can see what I mean.  Here is what the image says in case the image fails to load.  Events Events consist of three categories, all represented by a string:  Entity events Slash Commands MoLang Expressions  In detail: Entity Events: Server side (behavior packs) only. Currently, we only support entity events to self, and these take the form "@s event". These are events declared in the events section of the entity definition file. For example, in the cat.json, "minecraft:ageable_grow_up" event causes the kitten to grow up. This would take the form of "@s minecraft:ageable_grow_up" Slash commands: Server side (behavior packs) only. Any slash command can be invoked, such as /particle minecraft:example_smoke_puff ~ ~ ~. The assumed entity for the slash command is the invoking entity, so this particular slash command will spawn a smoke puff effect at the entity's location. MoLang Expressions: This executes a MoLang expression. The primary usage is to set MoLang variables that can be used later. For example, a state transition might be looking at a particluar MoLang variable, and this expression could change that variable. A particle effect on the entity might change color due to MoLang variables that the effect uses for color tints. An animation to move an arm might use a MoLang variable that was set by an animation event. // entity event (behavior packs only), put the particular event name` after the @s "@s minecraft:entity_event"  // slash command (behavior packs only), can be any server-side slash command // is invoked from the entity, so a teleport, for example, will teleport the entity by default "/tell @a this is a message"`  // MoLang Expressions, executes a molang expression on the entity "variable.something_to_set = 3;"   Am I misunderstanding?  If not, how do I do this?  If any of this is unclear to you please ask questions in the comments.  Thanks!

This question was recently split into different questions for each workaround. See   meta posts for more information.   Can you use NBT tags in commands? I’ve tried commands that normally work in Java Edition like: give @s minecraft:planks 30 1 {display:{Lore:["Wooden planks"]}} give @s stone_pickaxe{Unbreakable:1b} give @s item_frame{EntityTag:{Invisible:1b}} summon villager ~ ~ ~ {Offers:{Recipes:[{buy:{id:"emerald",Count:5b},sell:{id:"diamond_sword"}}]}} summon tnt ~ ~ ~ {Fuse:20s}


I have wanted to create a .desktop file to create an application icon which would execute a .run file as admin. Since the gksu package is deprecated, I've used  Exec=gnome-terminal --command="sudo /opt/lampp/manager-linux-x64.run"   in the .desktop file. This opens a new terminal window and I type my sudo password to open the application.  So, are there any better solutions, which are more elegant for instance without having a terminal window opened?

I've read a lot of threads about gksu being removed from many Linux flavours, including Ubuntu 18.04.  Many state that gksu is an abomination and no user should ever need to use anything like it.  I have 2 examples where, as far as I know, I must have something that allows me to run as root (not just for editing files).    First, I have a need to start mysql only after an encrypted folder is opened on (GUI) command.  This means having a script run by the encryption system that starts the mysql service.  That has to be done as root, so I use gksu in that startup script which asks me for a password.  How else can I start a service from a GUI system?  I also run Ubuntu system backups as root, otherwise many system files can't be backed up.  So the desktop file uses gksu to start the backup.  pkexec looks complicated, needing policy files.  Is that the only alternative, and if so, why is it any safer?  Other answers to similar questions don't seem to address individual issues that people have now that gksu is no more (or harder to find...).  I think such questions from non-expert users would benefit from more detailed answers.  I now have some, and so would like to answer my own question.


I am a level 6 bard playing a campaign in 5e. I have the ability "song of rest"      Beginning at 2nd level, you can use soothing music or oration to help revitalize your wounded allies during a short rest. If you or any friendly creature who can hear your performance regain hit points at the end of the short rest, each of those creatures regains an extra 1d6 hit points (PHB pg 54).   Does this work if they use a potion during the rest? How long is this ability active? What about if a cleric is using a mass heal spell, Or a paladin's Lay on hands? It does say when they regain health points. So can this potentially give them multiple cases of life gain? Or only with the use of Hit Dice?  Song of rest with potion (+1d6) song of rest with hit dice (+1d6) song of rest with mass cure wounds (+1d6)

In D&D 5e, the benefit of the Bard's "Song of Rest" feature triggers "if you or any friendly creatures who can hear your performance regain hit points at the end of the the short rest."  Does Song of Rest's benefit apply just when spending hit dice to regain hit points? Or does it apply to any other way that a player might regain hit points at the end of a short rest (e.g. by casting a spell, using a Second Wind, eating a Goodberry, etc.)?


I am working on a project and used a particle system to create the branches of a tree. I am now trying to make take that tree and create another particle system in order to create a forest with many of these trees. The problem is when I create the second particle system the trees show up without the branches of the tree or the first particle system. Lmk what I can do to solve this problem or if there is any other information you need to answer.

I have a seed object with some particle hair strands. I've specified this object to be instanced in another particle system, then specified that object to be instanced in yet another particle system.  To clarify:      I have a cube with hairs strands I have a Suzanne coated in cubes with hair strands (the hair strands only appear in the render, which is fine) I have another Suzanne coated in Suzannes, but these Suzannes don't have cubes or strands like I was hoping..     Is there a way to get the particle systems to keep recursing, so that the last Suzanne is coated in Suzannes coated in cubes coated in strands?


I sent a friend a question in the form:     Just trying to remember how we know each other?   That is a "statement" without the question mark at the end. Is there a term for this? Since it does not begin with a "How", "Why", "Where" etc..

I have often noticed people who make statements, actually ending with a question mark when written, but where there is no actual question asked.    The question is implied sufficiently enough in the context of the statement, and/or the previous statement that the question portion can be omitted.  Some examples:     Sandra: I'm not walking to the theatre as I didn't bring a jacket.Julie: I have a spare jacket?   In the above, it is clear that Julie is asking "would you like to borrow my spare jacket so that we can walk to the theatre".     Paul: We aren't going to Pizza Hut at lunch as it's too far to walk in an hour.Dave: I have my car today?   Again, it is clear that Dave is offering to drive and asking if that is an option.  Is there a term to describe this?


EDIT : How to Mix the different mechanisms (a , mx , ip4 ,  ptr and include) to create single SPF file from 4   I know that 2 simple SPF records like  v=spf1 include:_spf.google.com ~all v=spf1 include:otherdomain.com ~all   can be merged to one as  v=spf1 include:_spf.google.com include:otherdomain.com ~all   I have bit more complex SPF records with mechanisms  like a mx ip4  ptr and include  as shown below  v=spf1 a mx ptr include:icpbounce.com include:spf.mandrillapp.com ~all     v=spf1 mx ip4:x.x.x.x include:mktomail.com ~all      v=spf1 mx ip4:y.y.y.y include:mktomail.com ~all     v=spf1 include:spf.mandrillapp.com ?all   How can merge all this to one TXT record, as mandrilapp is giving me an error      has more than one TXT record that looks like an SPF record   I cant try a trial and error as its in production and i am very new to this SPF domain

This is a  about setting up .     I have an office with many computers that share a single external ip (I'm unsure if the address is static or dynamic). Each computer connects to our mail server via IMAP using outlook. Email is sent and received by those computers, and some users send and receive email on their mobile phones as well.  I am using  to generate an SPF record and I'm unsure about some of the fields in the wizard, specifically:   Enter any other domains who may send or relay mail for this domain Enter any IP addresses in CIDR format for netblocks that originate or relay mail for this domain Enter any other hosts which can send or relay mail for this domain How stringent should SPF-aware MTA's treat this?   the first few questions i'm fairly certain about... hope i have given enough info.


Hello I am currently scraping information from online and putting it into a list however the elements are appearing as :   ['\n      Michael\n    ',  '\n      Elad\n    ',  '\n      Yair\n    ',   '\n      Liron\n    ',   '\n      Idan\n    ',   '\n      Tomer\n    ',   '\n      Ofer\n    ',   '\n      Asaf\n    ',   '\n      Tomer\n    ',   '\n      Ronit\n    ',   '\n      Guy\n    ',   '\n      Lior\n    ']   Is there a way to format the list to erase the line indentations and the white space?   Thank you

What is the Python equivalent of Perl's chomp function, which removes the last character of a string if it is a newline?


So I'm running Ubuntu 18.04 from an external hard drive attached via USB to my Windows 10 machine. I boot it by using a Ubuntu USB booter and choosing the 'Linux' option from Windows' 'Advanced Restart' menu. I tried to be able to boot it on startup from the UEFI boot menu for a long time, to no avail.  It works perfectly fine except I need to resinstall everything every time I restart - I even get the 'Do you want to install/try Ubuntu' selection menu each time (though I don't need to actually install Ubuntu every time, just all the sudo apt-get stuff). Only data I've saved to the external hard drive disk persists.  Is there some configuration that will allow all of the packages I've installed in one session to remain for the next? I should mention that the external hard drive is cannibalized from an old laptop and requires a wall outlet to run, maybe that has something to do with it?

OS: Windows 7. I want install Linux Ubuntu on portable external Hard Drive USB 2.0. I read a variety of methods, but I'm confused by contradictory advices and methods. Actually, installing Ubuntu on anything other than clean PC looks much more complicated than installing Windows. I need to have Ubuntu package + Python 2.7 + C compiler installed. My external hard drive is partially filled, I need to keep all files.   Will Ubuntu run entirely on external hardrive, without writing anythinhg to Windows system folders and to registry?  Can anyone post detailed guide how install Ubuntu on external hard drive?


Is there any word for a person who does not like to share information?

What do you call a person who is unwilling to share information?


Consider the following MWE.   \documentclass{article} \usepackage{enumitem} \def\widestnumber{25}  \newlist{mylist}{enumerate}{1} \setlist[mylist,1]{      leftmargin=40pt,   labelsep=1.0em,    itemsep=0.0em,    topsep=0.5em,    label=\arabic*.,   widest*=\widestnumber}  \begin{document}  \begin{mylist}    \item Here is a list item which consists of two paragraphs. This is the first paragraph.      Here is the second paragraph. I want it to have a normal indent at the beginning.    \item Here is another item. \end{mylist}  \end{document}

I want to insert a paragraph or possibly even a box with a background color into a list that uses the whole \textwidth. Something like this:  1st item     a subitem 1    b subitem 2  2nd item    a subitee  \begin{use the full width}    [ Here the text should use the full text width ignoring the list indent] \end{use the full width}    b subitem 3rd item   The list is a normal enumerate.


I know that  states that if a system in equilibrium is at zero temperature, its entropy is minimum.   Expansion of the universe made a transition from  (rde) to matter dominated era(mde). So the same question  occurred to me as well. But the answers did not satisfy me indeed. How is it possible that rde had lower entropy than today even if it was at higher temperature in the very early beginning of the universe? Isn't there any contradiction here?

The Big Bang theory assumes that our universe started from a very/infinitely dense and extremely/infinitely hot state. But on the other side, it is often claimed that our universe must have been started in a state with very low or even zero entropy.   Now the third law of thermodynamic states that if the entropy of a system approaches a minimum, it's temperature approaches absolut zero.  So how can it be that the beginning universe had a high temperature and a low entropy at the same time? Wouldn't such a state be in contradiction to the third law of thermodynamics?


what are the difference between,  var Human = function(){ this.age = 21; };   and  Human.prototype.age = 31; var ME = new Human(); document.write(ME.age);    It showing output 21, why not 31 ?

What's the difference between  var A = function () {     this.x = function () {         //do something     }; };   and  var A = function () { }; A.prototype.x = function () {     //do something };


Which word or words can be used in order to denote the person standing just before the last person in a row? Is the word second last correct in this matter?

Actually, I'm not even sure if the "second-last" is the correct term. Here is how I would use it:     Go down the hallway, it's the second-last door on your right.    which I want to describe the door that is immediately next to the last door.   What are other ways to describe it? Can I say, e.g., next-last?   Also, how about the one that next to second-last? Can I say third-last?   EDIT: broadening the usage, can I say "this is the next-best choice"? Are there any other ways to express it?  Thanks


My issue was that when I was plugging in my XBox One controller in my Windows 7 PC, the error was popping up that the 'USB Device could not be identified.' Good job Microsoft.   The sad thing about this is that on Windows 7, the drivers for the Xbox One Controllers specifically are supposed to download automatically when the device is plugged in. Obviously, since the Device Manager cannot identify the device in the first place, it doesn't know what drivers it needs to automatically download.   Unfortunately for all of us, the solution to manually download the drivers on the support website () is, at the time of writing, obsolete.   The webpage instructs you to follow these instructions:    Navigate to the Xbox One Controller results page on the Microsoft Update Catalog Download the correct version of the driver for your operating system (64bit vs 32bit) Extract the contents of the .cab into a file directory. Right click on the xb1usb.inf file, click install, and click yes.   However, users will find that when doing 'Right Click/Install' on the 64bit version of the drivers that the method of installation is no longer supported in the file. It throws the following error:     The INF file you selected does not support this method of   installation

Following these  my aftermarket Xbox 360 controller is not working on Windows 7.  Any suggestions?


Please can someone explain the steps for deriving the probability density function of median for Normal Distribution

If I calculate the median of a sufficiently large number of observations drawn from the same distribution, does the central limit theorem state that the distribution of medians will approximate a normal distribution? My understanding is that this is true with the means of a large number of samples, but is it also true with medians?  If not, what is the underlying distribution of sample medians?


I recently spilled water on my computers keyboard, and as a result the left shift key seems to be stuck in the on position. This means that the system always boots into safe boot unless I hold down the option key. I have managed to change my password to one which is all caps and once I login I use keyremap4mac but it is still very annoying. Is there anyway which I can remap the keyboard during boot? Possibly with a startup bash script or something similiar? If that is not possible is there any way to use a script to bypass safe boot? I was planning on installing a new bootloader anyway in order to dual-boot linux, I don't know if this will help. Advice is appreciated.

This is an attempt to write a canonical QA for this issue, as per the Meta post:   I expect it to be periodically edited with the goal of becoming a comprehensive information resource.  I have a MacBook Pro that has a key(Shift, Return,   Command, P, etc.) that doesn’t respond when pressed or is stuck in the down position.    It's possible that my favorite beverage was spilled (or some other liquid damage).  It's also possible that I have no idea what happened.  It was working yesterday and suddenly today it's no longer working.  Is there any way to bypass or remap the key?  Can I  have the system ignore it completely?  (This question can also apply to external USB keyboards or the Bluetooth keyboards)


I have a specific sentence in which I feel inclined to use "your's" but in not sure if it's correct. Then sentence is:  "Every story has a beginning - This is your's."  What "your's" stand for here is simply "this is your story's beginning" but to spell it out like that doesn't create the same feeling.   Albeit, is this a correct usage of "your's"?  Edit: This is not a duplicate of "Yours vs your's" as I'm asking for a situation in which "yours" can't be used since it would mean their beginning, not their stories' beginning.

Which is correct “Is that yours?” or “Is that your’s?”?  I ask because it is possessive, so I would think it would be the latter, but I typically use and see the former usage.  Are there particular cases in which one should be used instead of the other? Or is one simply correct and the other not?  This is one of the few things that still confuse me, so help is greatly appreciated.


Is it possible to ungroup an imported Wavefront(.obj) object? I have created the object in EasyToy and would like to finish it with Blender due to it's better functionality.  The object looks like this:     But I can't select just for example an ear or eyeball. So my question is: is it possible to do this or do I have to select the single parts by selecting faces, edges etc.?

I've just made a set of armor by using a male body mesh model I downloaded and selecting certain faces from the model and duplicating them to create viable armor pieces.   Since the pieces are just duplicated from the same mesh male model, then it's still part of the same object.   How do I separate the armor piece from the model to make the pieces separate?


In how many ways can we assign $m$ employees to $n$ projects so that every employee is assigned to exactly one project and every project is assigned to at least one employee? Also, $m>n$.  My answer:  Let's choose $n$ employees from $m$ and assign them projects such that each project has exactly one employee working under it. Thus, $mPn$.  For the remaining $m-n$ employees, each employee can work under $n$ project options. Thus, $n^{m-n}$.  Thus, total answer $= mPn \cdot n^{m-n}$.  For $m = 5$ and $n = 4$, my answer $= 480$ and expected answer $= 240$.  For $m = 6$ and $n = 3$, my answer $= 3240$ and expected answer $= 540$.

It is quite easy to calculate the total number of functions from a set $X$ with $m$ elements to a set $Y$ with $n$ elements ($n^{m}$), and also the total number of injective functions ($n^{\underline{m}}$, denoting the falling factorial). But I am thinking about how to calculate the total number of surjective functions $f\colon X \twoheadrightarrow Y $.  The way I thought of doing this is as follows: firstly, since all $n$ elements of the codomain $Y$ need to be mapped to, you choose any $n$ elements from the $m$ elements of the set $X$ to be mapped one-to-one with the $n$ elements of $Y$. This results in $n!$ possible pairings. But the number of ways of choosing $n$ elements from $m$ elements is $\frac{m!}{(m-n)!\,n!}$, so the total number of ways of matching $n$ elements in $X$ to be one-to-one with the $n$ elements of $Y$ is $\frac{m!}{(m-n)!\,n!} \times n! = \frac{m!}{(m-n)!}$.  Now we have 'covered' the codomain $Y$ with $n$ elements from $X$, the remaining unpaired $m-n$ elements from $X$ can be mapped to any of the elements of $Y$, so there are $n^{m-n}$ ways of doing this. Therefore I think that the total number of surjective functions should be $\frac{m!}{(m-n)!} \, n^{m-n}$.  Is this anything like correct or have I made a major mistake here?


So I am not able to target my functions inside my jQuery object at all and I want to see if someone is able to assist me with this: I keep getting the following error: getAuthentication is not defined when I attempt to use it on my on click call - I want to be able to click #insta-auth and have the current window open the auth_url inside the getAuthentication() function. So here is what I have: <button id="insta-auth" class="loginBtn loginBtn--facebook">Authenticate Instagram</button>  <script> // Setup our Instagram object var FHInstagram = window.FHInstagram || {}; FHInstagram.name = "cwd";  (function ($, window, document, undefined) {          // Define our Instagram object     const Instagram = {         APP_ID: '32222',         API_URL: 'https://graph.instagram.com/',         API_OAUTH: 'https://api.instagram.com/oauth/authorize',         API_OAUTH_TOKEN_URL: 'https://api.instagram.com/oauth/access_token',         API_FIELDS: 'caption,media_url,media_type,permalink,timestamp,username',      initialize: function (options, element) {         this.element = element;         this.$element = $(element);         (this.accessToken = $.fn.FHInstagram.accessData.accessToken), (this.options = $.extend({}, $.fn.FHInstagram.options, options));          this.messages = {             defaultImageAltText: "Instagram Photo",             notFound: "This user account is private or doesn't have any photos.",         };          this.getPhotos();     },      // Call the API to grab all of our items     getItems: function () {       return $.ajax({         type: "GET",         dataType: "jsonp",         cache: false,         url: this.API_URL + 'me/media?fields=' + this.API_FIELDS + "&access_token=" + this.accessToken,       });     },      // Authenticate Instagram     getAuthentication: function () {         auth_url = API_OAUTH + "?client_id=" + this.APP_ID + "&redirect_uri=" + encodeURIComponent(window.location.origin) + "&scope=user_profile,user_media&response_type=code"         return auth_url;     },   };    jQuery.fn.FHInstagram = function (options) {     if (jQuery.fn.FHInstagram.accessData.accessToken) {       this.each(function () {         var instagram = Object.create(Instagram);         instagram.initialize(options, this);       });     } else {       $.error("You must define an accessToken on jQuery.FHInstagram");     }   }; })(jQuery, window, document);  $('#insta-auth').on('click', function() {     window.location = getAuthentication(); }); </script>

What is the scope of variables in javascript? Do they have the same scope inside as opposed to outside a function? Or does it even matter? Also, where are the variables stored if they are defined globally?


I get this problem when doing sudo apt-get update && upgrade on Ubuntu 16.04:  Err:39 http://archive.getdeb.net/ubuntu xenial-getdeb InRelease Could not connect to archive.getdeb.net:80 (144.76.200.19), connection timed outFetched 4,750 kB in 2min 0s (39.5 kB/s) AppStream cache update completed, but some metadata was ignored due to errors. Reading package lists... Done W: Failed to fetch http://archive.getdeb.net/ubuntu/dists/xenial-getdeb/InRelease Could not connect to archive.getdeb.net:80 (144.76.200.19), connection timed out W: Some index files failed to download. They have been ignored, or old ones used instead.   How can I fix this?

I'm trying to install programs/files from the getdeb repo but get a "check your internet connection" error.  Programs than I've tried include Qbittorrent and Mozilla-Plugin-VLC.    Through the terminal I get the following errors:  Err http://archive.getdeb.net/ubuntu/ natty-getdeb/apps qbittorrent amd64 2.8.2-1~getdeb2   Could not connect to archive.getdeb.net:80 (209.105.191.78). - connect (113: No route to host) E: Failed to fetch http://archive.getdeb.net/ubuntu/pool/apps/q/qbittorrent/qbittorrent_2.8.2-1~getdeb2_amd64.deb: Could not connect to archive.getdeb.net:80 (209.105.191.78). - connect (113: No route to host)   &  Err http://archive.getdeb.net/ubuntu/ natty-getdeb/apps mozilla-plugin-vlc amd64 1.1.10-1~getdeb1   Could not connect to archive.getdeb.net:80 (209.105.191.78). - connect (113: No route to host) E: Failed to fetch http://archive.getdeb.net/ubuntu/pool/apps/v/vlc/mozilla-plugin-vlc_1.1.10-1~getdeb1_amd64.deb: Could not connect to archive.getdeb.net:80 (209.105.191.78). - connect (113: No route to host)   I'm not having any problems adding/removing other programs/files from my machine.  Is there a problem with GETDEB repo (and if so, is there any way to fix it on my end) or is there something wrong with my computer's configuration?


this code prints Kth to the last element in the LinkedList using recursion.  With LinkedList containing abcdef and k=4.  The expected output is cdef  With recursion, I wanted to use a local Iterator to trace the position of the node, itrLocal in method kToLast().  But, I found that itrLocal was not  saved when returned from the recursive call.   Is this a bug ?    import java.util.Iterator; import java.util.LinkedList;  //with recursion  O(n) space and O(n) time. public class KthToLast {      public KthToLast() {     }      public static void main(String[] args){          LinkedList s = new LinkedList();          s.add("a");         s.add("b");         s.add("c");         s.add("d");         s.add("e");         s.add("f");          KthToLast k = new KthToLast();         LinkedList resultList= new LinkedList();         int n = k.kToLast(s.iterator(), 4, resultList);          }//main       private int kToLast(Iterator<String> itr, int k, LinkedList resultList)    {          Iterator<String> itrLocal = itr;           if (!itr.hasNext()) {            return k;          }         else {             String data = (String) itr.next();              int n=  kToLast(itr,k, resultList)-1;              if (n >= 0) {                 resultList.add(data);             }             if (n==0){                 Iterator reverse = resultList.descendingIterator();                 while (reverse.hasNext()){                     System.out.print(reverse.next());                 }//if                //value of data is reserved for each recursion             if  (n >= 0) {              /* why would itrLocal change with itr ? itrLocal at each                  recursion call was not reserved.   is this a bug ?              */               while (itrLocal.hasNext()){                   System.out.println(itrLocal.next());               }                            }//if                        return n;                    }//else                  }//ktolast }//class

I always thought Java uses pass-by-reference. However, I've seen a couple of blog posts (for example, ) that claim that it isn't (the blog post says that Java uses pass-by-value). I don't think I understand the distinction they're making. What is the explanation?


I would like to create a show/hide button that appears on a typeset PDF so that when it is clicked, the content appears. This is similar to the ideas here:  and here: , but I would like the option to show up in the PDF itself as a simple button that could be clicked (or something similar) Ideally, this would end up looking something like this:  \documentclass{article} \newcommand{showhide}[1]{Does what I am describing}  \begin{document}  \showhide{Displays a button, that when clicked, shows this text and when clicked again, hides this text.}  \end{document}   Anyone know how do do this, or something similar?

Is it possible to get tooltips into a LaTeX pdf?  I am working on my CV. I would like to show some more information on my electronic version once you swipe over that field with the mouse. i.e. when swiping with the mouse over education I want to show my subjects taken in undergrad through a tooltip.  Is this possible and if yes would if work for all kind of pdf readers?


Let $v_1, v_2,\dots, v_n$ be a basis of the vector space $V$. Let $k$ be an integer such that $1 \leq k \leq n$, and put $U = \operatorname{Span}\{v_1, . . . , v_k\}$ and $W = \operatorname{Span}\{v_{k+1}, . . . , v_n\}$.  I want to show that $V = U\oplus W$.  Would it be enough to prove that $U$ and $W$ are bases of $V$ using linear independence, and then show that there are unique $v\in V$ for every $v = u + w$?

Prove that if $W_1$ is any subspace of a finite-dimensional vector space $V$, then there exists a subspace $W_2$ of $V$ such that $V = W_1 \oplus W_2$   What I have done so far is to note that since $V$ is finite and $W_1$ is a subspace of $V$, we have $\dim(W_1) \leq \dim(V)$. If we have equality, then let $W_2 = \{0\}$, so that we have $V= W_1 \oplus W_2$. So now I need to look at the case when $\dim(W_1) \lt \dim(V)$.  What I have tried for this case is to let $$\beta = \{v_1,v_2,..,v_n\}$$ be a basis for $V$ and $$\gamma=\{u_1,u_2,..,u_m\}$$ a basis for $W_1$. My idea was to extend $\gamma$ to a basis for $V$, so let $$\alpha=\{u_1,u_2,..,u_m,w_1,w_2,..,w_{n-m}\}$$ be the extension of $\gamma$ to $V$, where $w_1,w_2,..,w_{n-m}$ are basis vectors for $W_2$. If I'm doing this right then I would just have to show that $W_1 \cap W_2 = \{0\}$ and $W_1 + W_2= V$   Am I heading in the right direction? Any hints would be greatly appreciated.


Using Blender 2.8, when creating a primitive circle using the API like this: import bpy from mathutils import Vector, Euler bpy.ops.mesh.primitive_circle_add(vertices=8, enter_editmode=False, location=(0, 0, 0.03), rotation=Euler((0,0,0.3927)), radius=0.05) bpy.ops.object.transform_apply()  It ends up with normals like this, pointing upwards a bit:  I noticed when not setting the location of the circle, like so, it does not happen. import bpy from mathutils import Vector, Euler bpy.ops.mesh.primitive_circle_add(vertices=8, enter_editmode=False, location=(0, 0, 0), rotation=Euler((0,0,0.3927)), radius=0.05) bpy.ops.object.transform_apply()  I have failed thus far to understand why. In any case, I would like the normals to be pointing outwards, like so:  Is this possible? If yes, how? Thanks.

In the duplication options for the dupli verts there is a option for Rotation. Witch brings me to my question, is there anyway to rotate a vertex? Vertex's have normals, is there any way to control which way the normal of a single unconnected vertex points?


I was looking through the various nuclear fusion approaches and it struck me that they all suffered from one of two problems. Either they wasted a lot of energy trying to accelerate fusion fuel to the needed speed by using heat, which produced a distribution of particle energies instead of a single energy, or they couldn't get the needed particle density for the reaction to progress fast enough to burn all the fuel before it flies apart.   The reactor that comes closest in terms of accelerating fusion fuel efficiently is the polywell, because it uses an electrostatic potential difference to get the fuel to the needed speed for fusion. However, since the nucleii are ions, it is very hard to get the densities (150 g/cm^3) for rapid fuel burn.   So a thought came to me. Why can't an electrostatic accelerator accelerate deuterium ions to fusion energies, and have the accelerators arranged to have the ion beams converge to a focal point. However, after accelerating the ions, and moving them towards the focus, neutralize the ions using an electron beam, so the particle beam is both at high speed, and neutral to allow compression without electrostatic repulsion.   I think this might, work and googled it and couldn't find anyone having attempted this. Am I missing something fundamental here? If so, what is it? Why wouldn't this work?

So I know the basic gist is that fusion power's main issue is sustaining the fusion. I also know that there are two methods. The Torus method and the laser method. The torus magnetically contains plasma and heats it with radiation and accelerates the plasma around to make strong enough collisions that protons fuse. The laser method uses 192 lasers and focuses it on tiny frozen hydrogen pellets and aims to initiate fusion each time pellets are dropped.  The though struck me when we could sorta combine the two designs together. The torus doesn't have to worry about making fusion happen at a specific location but it has issues in that the plasma is unevenly heated and leaks. On the other hand, the laser design is extremely complicated in the level of precision needed and would have to repeat this for every pellet. This lead me to think to make something precise and contained at the same time.  I see that particle colliders are able to direct two beams of protons and have them collide at a specific spot with a very precise energy. Couldn't we tune the energy of the two beams of protons to the energy required for them to fuse? We have the ability to smash them into bits, surely we have the ability to have them fuse. (I'm thinking about the type of collider that circles two beams in opposite directions)  It would be at much lower energies than normal colliders and would be very precise and it would be possible to fuse at a specific location that has greater leeway because for protons that missed collision, they'd just circle around again! Thus protons would efficiently be used and very little would be wasted. There wouldn't be problems of plasma leakage because we are focusing them in a thin tight beam.   It seems that this idea has girth, or I feel this way at least, can someone back me up by offering some calculations on how to calculate the efficiency? How would I go about calculating the two circling beams of protons and at what specific velocity would be needed? etc.


I looked all over this profile: , and was unable to locate a "Flag for Moderator" button. But as you can see, it's well needed: Warning: Graphic!     So, I located one of his posts to flag for moderator attention, but there should be an easier way. And if there is - then it should be much more noticeable and easier to find. My proposal should be clear by now, but if it's not; please add a "Flag User" button within a user's profile.

I think the community does a great job policing questions/answers, etc. and the community has some good tools available to do this.  Between flagging questions with some reasons behind it and editing posts, closing them, and deleting them, the only thing that seems to be missing to me is the ability to flag a user.  Reasons to flag a user as abusive:   Duplicate User Abusive Behavior Offensive user name or profile User profile consists of spam Others?


Could you advise - which is correct?  It's my and Louise's cat. It's mine and Louise's cat. It's Louise's and my cat.  Thanks

I just stumbled upon a :     My wife and I's seafood collaboration dinner. How does it look?   Sure enough, the top comment immediately points out that it should be "my wife's and my". However, a cross-post to the Grammar subreddit produced :     It's fine as it is written. "my wife and I" is a noun phrase, functioning as a subjective pronoun in the singular and made possessive with the apostrophe. It is exactly the same as "our".      It seems weird because you would never use "I's" on its own but it is not on its own here - it is part of a noun phrase.   That's a rather intriguing argument. Does it hold any water?


An interesting thought struck me today, can sound be recovered? I mean sounds from the past, maybe a year or a millennium back.

From this , I am certain that it is possible to view the past.   But then this interesting question came to me.  Is it possible to hear the past?  Ok, you might say, "Well, we are hearing the past, aren't we?" and go onto immense details about the speed of sound against the difference and stuff.  But what if I wanted to hear the sound of a place extremely close by days, weeks, months or even years back?  Would that be possible?


I know the eigenvectors of the Laplacian of a ring graph with $n$ vertices are  $$x_k(u) = \sin \left( \frac{2 \pi k u}{n} \right)$$  and  $$y_k(u) = \cos \left( \frac{2 \pi k u}{n} \right)$$  for $1 \leq k \leq \frac n2$. However, I can't understand which one is an eigenvector of the Laplacian of the ring graph. Actually, what is the value of the $i$-th element of the $j$-th eigenvector of the Laplacian of a ring graph with $n$ vertices?  I couldn't find anything that directly explains this issue.

The eigenvectors of the Laplacian of a Ring graph with $n$ vertices are:  $x_k(u) = \sin(2\pi ku/n)$ and  $y_k(u) = \cos(2\pi ku/n)$  for $1\leq k \leq n/2$. The explanation according to  is:     The best way to see that $x_k$ and $y_k$ are eigenvectors is to plot the graph on the circle using these vectors as coordinates. That they are eigenvectors is geometrically obvious.    Why is this "geometrically obvious"? I can see that embedding the graph into the plane using $x_k$ and $y_k$ as coordinates places the vertices uniformly over the unit circle. What I cannot understand is why the eigenvectors of the Laplacian must produce this embedding.


Given an user made a clean and successfull:  sudo rm -r * #erase all folders and files recursively starting from root   How to get all the hard drive's data back ?

Possible Duplicate:          Hi,  Is there any simple way to undo an rm command?  The question is purely theoretical; I have NEVER deleted the log of a benchmark queue who took a whole lunchtime to run.


In java passing an array mimics a concept called "pass-by-reference", meaning that when an array is passed as an argument, its memory address location (its "reference") is used. In this way, the contents of an array can be changed inside of a method, since we are dealing directly with the actual array and not with a copy of the array.  Now in this example       class ChangeIt      {     static void doIt(int[] arr)     {     arr[0]=arr[arr.length-1];     /*arr=null;*/     }     }     public class TestIt {       public static void main(String[] args) {     int[] arr={1,2,3,4,5};     ChangeIt.doIt(arr);     for(int i :arr)         System.out.print(i +" ");       }      }   If I run the program i get the output 5 2 3 4 5  but if I comment this line in my program         arr[0]=arr[arr.length-1]; and uncomment this line in my program         arr=null; still I get the  output as 1 2 3 4 5  My question is why is the java.lang.NullPointerException is not raised when passing an array mimics a concept called "pass-by-reference" ?

I always thought Java uses pass-by-reference. However, I've seen a couple of blog posts (for example, ) that claim that it isn't (the blog post says that Java uses pass-by-value). I don't think I understand the distinction they're making. What is the explanation?


In the following MWE, what is responsible for the large space before the align environment? How can I remove it (it doesn't appear if I change to \[ \] and remove amsmath) ?  \documentclass{article}  \usepackage[english]{babel} \usepackage{amsmath,amssymb} \usepackage{lipsum}  \begin{document} \setlength{\parskip}{0pt} \setlength{\abovedisplayskip}{0pt} \setlength{\belowdisplayskip}{0pt} \setlength{\abovedisplayshortskip}{0pt} \setlength{\belowdisplayshortskip}{0pt}  \lipsum*[2]  \lipsum*[2]  \begin{align*}1, 2, 3\end{align*}  \lipsum*[2]  \lipsum*[2] \end{document}   I have read  (but it doesn't cover the case in which there's a \par before \align and  (but it attributes the space to \parskip, which seems wrong: setting \parskip to 0 pt doesn't remove the space). I also read  and , but they just say that one shouldn't leave a \par before an \align.  I'm curious to know what actually causes this blank space, even with all seemingly relevant lengths set to zero.   Edit for Reopen   is related, but it doesn't address the why: it says that leaving a blank line in the source causes the space but it doesn't say who is adding this space (and it's clearly an amsmath-specific this: the regular displaymath doesn't do that).

What is the typographic reasoning here? Does it make the text look less crowded?


When I use sudo apt-get -f install in terminal, the following happens:  Do you want to continue? [Y/n] y (Reading database ... 237694 files and directories currently installed.) Preparing to unpack .../linux-tools-3.16.0-31_3.16.0-31.41_amd64.deb ... Unpacking linux-tools-3.16.0-31 (3.16.0-31.41) ... dpkg: error processing archive /var/cache/apt/archives/linux-tools-3.16.0-31_3.16.0-31.41_amd64.deb (--unpack):  trying to overwrite '/usr/lib/libcpupower.so.3.16.0-31', which is also in package linux-lts-utopic-tools-3.16.0-31 3.16.0-31.41~14.04.1 dpkg-deb: error: subprocess paste was killed by signal (Broken pipe) Errors were encountered while processing:  /var/cache/apt/archives/linux-tools-3.16.0-31_3.16.0-31.41_amd64.deb E: Sub-process /usr/bin/dpkg returned an error code (1)

For example:  $ sudo apt-get install curl Reading package lists... Done Building dependency tree Reading state information... Done You might want to run 'apt-get -f install' to correct these: The following packages have unmet dependencies: bsh : Depends: libjline-java but it is not going to be installed groovy : Depends: libjline-java but it is not going to be installed rhino : Depends: libjline-java but it is not going to be installed E: Unmet dependencies.   Try 'apt-get -f install' with no packages (or specify a solution).   I get the same or similar errors when I attempt to install clojure1.3, leiningen, and several other packages.   When I try the suggestion made in the error message, this is what happens:  $ sudo apt-get -f install  Reading package lists... Done Building dependency tree        Reading state information... Done Correcting dependencies... Done The following packages were automatically installed and are no longer required:   diffstat linux-headers-3.2.0-26-generic linux-headers-3.2.0-26 dh-apparmor dkms html2text libmail-sendmail-perl libsys-hostname-long-perl Use 'apt-get autoremove' to remove them. The following extra packages will be installed:   libjline-java Suggested packages:   libjline-java-doc The following NEW packages will be installed:   libjline-java 0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded. 23 not fully installed or removed. Need to get 0 B/72.0 kB of archives. After this operation, 129 kB of additional disk space will be used. Do you want to continue [Y/n]? Y (Reading database ... 226243 files and directories currently installed.) Unpacking libjline-java (from .../libjline-java_1.0-1_all.deb) ... dpkg: error processing /var/cache/apt/archives/libjline-java_1.0-1_all.deb (--unpack):  trying to overwrite '/usr/share/java/jline.jar', which is also in package scala 2.9.2-400 Errors were encountered while processing:  /var/cache/apt/archives/libjline-java_1.0-1_all.deb E: Sub-process /usr/bin/dpkg returned an error code (1)  $ sudo apt-get upgrade Reading package lists... Done Building dependency tree        Reading state information... Done You might want to run 'apt-get -f install' to correct these. The following packages have unmet dependencies:  bsh : Depends: libjline-java but it is not installed  groovy : Depends: libjline-java but it is not installed  rhino : Depends: libjline-java but it is not installed E: Unmet dependencies. Try using -f.


I'm embarrassed to ask this. At one time I knew the answer and even had a printed copy of the code. I have tried texdoc with various options but was unable to come up with the one I needed.  At the moment I am particularly interested in the definitions of \addcontentsline, \contentsline, \addtocontents and any friends.  GOM

I can't find official documentation for the \@startsection command. I already looked in:   LaTeX Wikibook LaTeX: Structured document for TEX, 2008 beginLatex — a book that comes with ProTeX in the files that comes with MikTeX in the folder doc   and Google. I found a lot of sites that show examples and discussions about it but I'd like to find the official help or document.


As we know, in java and some other object-oriented programming languages, fields value can be set in constructor or be initialized in fields declaration statements. I want to know the essential differences between the two ways above. And what conditions I should initialze fields by constructor and what condtions I should't.  Thanks for your help.

I've been programming in C# and Java recently and I am curious where the best place is to initialize my class fields.  Should I do it at declaration?:  public class Dice {     private int topFace = 1;     private Random myRand = new Random();      public void Roll()     {        // ......     } }   or in a constructor?:  public class Dice {     private int topFace;     private Random myRand;      public Dice()     {         topFace = 1;         myRand = new Random();     }      public void Roll()     {         // .....     } }   I'm really curious what some of you veterans think is the best practice. I want to be consistent and stick to one approach.


Stewart in "Multivariate Calculus" defines a conservative vector field as a gradient of some scalar function. He goes on to say that a conservative vector field has zero curl. How about $$f(x, y, z) = \begin{cases} \frac{xy(x^2-y^2)}{x^2+y^2} &\mbox{if } (x,y,z) \neq 0 \\ 0 & \mbox{if } (x,y,z)=0, \end{cases}$$ which according to  has second partials on all of $\mathbb{R}^3$ and satisfies $f_{xy} (0,0,0) \neq f_{yx} (0,0,0)$? If I'm not mistaken, won't the gradient of this function have a non-zero curl at $(0,0,0)$?

I know that for a continuously differentiable vector field $F: D \subset R^3 \to R $ where $D$ is an simply connected subset of $R^3$ to be conservative, it must satisy $curl(F)(P) = 0$ at every $P \ \epsilon \ D$.   But $curl(F)(P) = 0$ for every $P \ \epsilon \ D$ is a necessary condition for the vector field to be consevative only when the vector field is continuously differentiable. So what I want to ask is the follwing:    Does there exist a conservative vector field  which is differentiable but not continuously differentiable and whose $curl \ne 0$ at every point in its domain? If not can we show that a differentiable vector field must always have a vanishing curl?


I have Windows and Ubuntu both installed in my laptop. Recently, during Windows installation when the computer took an update, the whole computer broke down. I had to fix the boot loader with Boot-Repair from a live Ubuntu USB. I have Ubuntu back, but after repair it is no longer possible to login into Windows. I checked my HDD with GParted, and it was showing errors in the Windows partition and also other NTFS partition. I am trying to fix the partition with the following commands but still having this error.   rashed@rashed:~$ sudo ntfsfix /dev/sda2 Mounting volume... OK Processing of $MFT and $MFTMirr completed successfully. Checking file system overflow... FAILED Error: Failed to fix the alternate boot sector   Is there a way to fixed the problem?

I installed Ubuntu on my laptop and something happened and my Windows 7 bootloader is missing. I can boot only Ubuntu. So, I tried to do something like suggested here  or , but when I see system recovery option there is no Windows 7 option.


Prove that any smooth, orientable, and connected surface can be equipped with a Riemann surface structure (in the sense of a complex 1-dimensional manifold). My idea is to modify the chart so that the transition map satisfies the Cauchy-Riemann equation and is thus holomorphic. Since the manifold is orientable, the jacobian of the transition maps everywhere is invertible. And say let $f = \phi_\alpha \circ \phi_\beta^{-1}$ for some transition maps  on $U \subset R^2$. I want to compose each $\phi_\alpha$ with some $\psi_\alpha$ where $$J_{\psi_\alpha \circ \phi_\alpha \circ \phi_\beta^{-1}\circ \psi_\beta^{-1}}(\psi_\beta^{-1}(p))= J_{\psi_\alpha}(f(p))J_f(p)J_{\psi_\beta^{-1}}(\psi_\beta^{-1}(p))$$ such that $$J_{\psi_\alpha}(f(p)) = \begin{bmatrix}      a &b \\  b & -a \end{bmatrix}^{\frac{1}{2}}\begin{bmatrix}      \partial_xf_1(p) &\partial_yf_1(p) \\  \partial_xf_2(p) & \partial_yf_2(p) \end{bmatrix}^{-\frac{1}{2}}$$ and $$J_{\psi_\beta^{-1}}(\psi_\beta^{-1}(p)) = \begin{bmatrix}      \partial_xf_1(p) &\partial_yf_1(p) \\  \partial_xf_2(p) & \partial_yf_2(p) \end{bmatrix}^{-\frac{1}{2}}\begin{bmatrix}      a &b \\  b & -a \end{bmatrix}^{\frac{1}{2}}$$   for some $a,b$ properly chosen. If such construction exists, then the jacobian for the new transition map is $\begin{bmatrix}      a &b \\  b & -a \end{bmatrix}$, satisfying the Cuacy-Riemann equation and thus the transition holomorphic. Does such construction work and does there exist such $\psi_\alpha$? I think properly not because I didn't use the connectedness property. So is there any modification I can do to make this construction valid?

I am trying to understand the fundamentals of Riemann surface theory and so far I have the following:  --Definition 1. A conformal structure on a Riemann surface $\Sigma$ is an equivalence class of metrics $$ [g]=\{e^{2u}g \colon u\in \mathcal{C}^\infty(\Sigma)\} $$  --Definition 2. A complex structure on a Riemann surface $\Sigma$ is an equivalence class of complex atlases, where two atlases are considered equivalent iff their union forms a new complex atlas.  Note 1. Each complex structure has a canonical representative given by the maximal atlas  ---Riemann's Uniformization Theorem. In any given conformal structure, there exists a unique metric with constant curvature of either $1,0$ or $-1$.   Note 2 This gives a means of choosing a canonical representative for each conformal structure.  My questions are these:  (I) Which theorem tells us that there is a bijection between these two definitions of conformal and complex structures?   (II) What is meant by the "Riemann moduli space"?  Many Thanks, A.  EDIT: In establishing the claim (I), it appears to be neccessary to take as assumption that a surface is orientable.


Where can I ask Health and Medical related questions on this site?  Is there a stackexchange site to ask questions about Health and Medical ?

Is there any Stack Exchange website to ask questions related to medical?  Is the physical fitness website including medical too? Can anyone ask questions related to psychology?


I am using xampp Apache server but it works locally i want to access it from public ip and i know the whole process but i am stuck how to change the port for Apache server because i dont want to access it with port 80 but is it possible that apache will run on other port please help and also how to change the port of mysql

My website work only if I run:     domain.com:44400   How to set port 44400 as the default in Apache?  I need have access by domain.com not domain.com:44400


The question I am looking at asks to use a combinatorial argument to show that   $$ \begin{bmatrix} n \\ 2 \\ \end{bmatrix} = \frac{n!}{2} \sum_{m=1}^{n-1} \frac{1}{m(n-m)}$$  I tried to use the recurrence relation for Stirling numbers of the first kind but couldn't find a way to make this work, help appreciated thanks.

How do I show that   $${ n\brack 2} = \frac{n!}{2} \sum_{m=1}^{n-1} \frac{1}{m(n-m)}$$  using a combinatorial argument?  My definition of ${n \brack 2}$ is "the number of elements of $S_n$ which can be decomposed as the product of exactly $2$ disjoint cycles".


I'm formatting a table, and I the bottom row has to have the "table notes". I'm not allowed to use the threeparttable package (or any other special package). I know I can use something like  \multicolumn{ncols}{p{10cm}}{Contents}   or  \multicolumn{ncols}{p{0.8\textwidth}}{Contents}   but I want the width of this cell to be computed automatically: it should be the width of the table, so something like \tablewidth (but that one doesn't exist).  Is this possible? If yes, how? Thanks in advance.

I have a two column table with a single multicolumn spanning both of them. The text on that multicolumn is rather long so I need to set its width so it wraps around. I can set the width with \multicolumn{2}{p{whatever}}{text} but what should I set "whatever" to? What is the actual width of a table? Is there a variable holding that value? I first thought to use \textwidth but that's not it. Building the document on draft mode shows that it's going out a tiny bit. The following table should show my problem. In draft mode will display a black box on its side. \begin{tabular}{l l}   \toprule   \multicolumn{2}{p{\textwidth}}{\lipsum[1]} \\   \bottomrule \end{tabular}  I do have more rows, I'm just keeping the example simple. I'm using the memoir document class. The actual text inside the multicolumn is using the seqsplit package. EDIT: I should have been more specific with the question. The only row that would make the table go over the limit is the one that I'm also trying to limit. And by limit I mean, so I don't get an overfull warning. So my question can be better rephrased as how to find the available space for a table so it is not overfull?


I'm a brand new user to Ubuntu and need some help installing programs. I can't get them to install and I don't know why. I download them from their websites, such as google chrome download, but after that I can't do anything. I'm starting to think it's because I'm "Trying Ubuntu". Is this true? Thanks for helping! :)

How can I install applications like Google Chrome on Ubuntu?  Are there any commands to install an application?    Index of answers:


I am using a desktop application that reads/writes folders and files on the local filesystem.  PROBLEM: Some of these files have paths longer than 260 characters, triggering such errors:     PathTooLongException: The specified path, file name, or both are too long. The fully qualified file name must be less than 260 characters, and the directory name must be less than 248 characters.   Question: How to make Windows allow long paths? I am using a wide array of Windows versions so I appreciate answers split by versions.  Different from  as that question is only about a missing option.

For some time, Microsoft has supported an option to remove the limit of 260 symbols for NTFS file name length.  The web is full of articles, describing what should be done.   Hit the Windows key, type gpedit.msc and press Enter. Navigate to Local Computer Policy > Computer Configuration > Administrative Templates > System > Filesystem > NTFS. Double click the Enable NTFS long paths option and enable it.   However, I don't have such option. Please see the screenshot below:    Am I missing some Windows update, or is it something else?


With a macro such as:  \def\naive{na\"{\i}ve}   I find that the space which I would hope to follow it, is absent. So, with  the \naive approach   I get     the naïveapproach   in the output. How do I bring back the space?

I have a definition:  \newcommand{\arnold}{Arnold Schwarzenegger}   When I refer to it by:  \arnold is a   it is rendered as:   Arnold Schwarzeneggeris a    In order to have a space in front of "is" I would need to write  \arnold\ is a   Is there some other shorter way?


I often use an array modifier (or two) to quickly create a grid of identical or symmetric objects, which can be really useful when modeling all sorts of man-made objects. Once I've made the grid, though, is there any way for me to make it so that each of the objects are individually manipulatable?  Simply applying the modifier does not seem to be the full answer, since it still only allows me to select the grid-of-objects as a whole in object mode. Is there any way to separate them so I work with them each individually?


I'm not sure if this is a duplicate question (I can't find anything like it), but I've tested using the == operator on 2 separate strings with the same value in 2 different IDEs and both have worked? I'm especially confused with this snippet of code:       public static void main(String args[]) {         String s1 = new String("aaab");         String s2 = new String("aaa");         System.out.println(Integer.toHexString(s1.hashCode()));         System.out.println(Integer.toHexString(s2.hashCode()));          s2 += "b";         System.out.println(Integer.toHexString(s1.hashCode()));         System.out.println(Integer.toHexString(s2.hashCode()));          Boolean b = s1==s2;         System.out.println(s1==s2);         System.out.println(b);         if (s1.equals(s2)){             System.out.println("this works");         }     }   (sorry if my formatting kinda sucks) For me, the console output is  2d9041 17841 2d9041 2d9041 false false this works   (I know the memory addresses might be different for different people, the point is the similarity between the two) This output doesn't make sense to me? Shouldn't s1==s2 return true because the memory addresses are the same? Is this an OS/Windows thing? Or an IDE thing? Sorry for the long question and thank you for any answers

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


I've found this example somewhere, and I cannot understand it.  >>> mult = [lambda x:x*i for i in range(4)] >>> mult [<function <listcomp>.<lambda> at 0xb6823464>, <function <listcomp>.<lambda> at 0xb682341c>, <function <listcomp>.<lambda> at 0xb68234f4>, <function <listcomp>.<lambda> at 0xb682353c>] >>> [m(2) for m in mult] [6, 6, 6, 6] >>>    As I see, the first line creates a list of lambda functions which I can call afterwards. What I don't understand is the output of [6,6,6,6]. As I can see, the elements of mult are located in different parts of memory, so, these are not several references to the same data block. But why do they produce the same results? Do all these functions reference the same i (which is the last one, which is 3), and why is this happening? And is there a quick way to make such a list of lambdas that would produce [0,2,4,6] instead?

The following test fails:  #!/usr/bin/env python def f(*args):     """     >>> t = 1, -1     >>> f(*map(lambda i: lambda: i, t))     [1, -1]     >>> f(*(lambda: i for i in t)) # -> [-1, -1]     [1, -1]     >>> f(*[lambda: i for i in t]) # -> [-1, -1]     [1, -1]     """     alist = [a() for a in args]     print(alist)  if __name__ == '__main__':     import doctest; doctest.testmod()   In other words:  >>> t = 1, -1 >>> args = [] >>> for i in t: ...   args.append(lambda: i) ... >>> map(lambda a: a(), args) [-1, -1] >>> args = [] >>> for i in t: ...   args.append((lambda i: lambda: i)(i)) ... >>> map(lambda a: a(), args) [1, -1] >>> args = [] >>> for i in t: ...   args.append(lambda i=i: i) ... >>> map(lambda a: a(), args) [1, -1]


A black body hypothetically absorbs all wavelengths of light and simultaneously emits all of them at the same time. Since the visible spectrum combines into white light, is true to say that emitted radiations must also appear white?

I know a black body is an object that absorbs all wavelengths of light, and also emits all wavelength of light too back out, but if it emits all wavelengths of light, why does it appear black, as all wavelengths combined appear white?  Also, with stars, I know they are assumed to be black bodies, but do they appear a certain colour just because they emit more of one wavelength than any other.   Edit: Looking at the link in the comments, I kind of understand why black bodies don't have to be black, but what does,it mean for something to be the colour black, like a black radiator? is black paint a black body?


Prove mathematical induction $$\sum_{i=0}^{k-1} 2^i = 2^k-1$$

Possible Duplicate:          Proof to the formula  $$1+x+x^2+x^3+\cdots+x^n = \frac{x^{n+1}-1}{x-1}.$$


I will refomulate my question() because it seems  that i did not make it clear. In order to have  $G_c^{(2)}(x_1,x_2)=G_0^{(2)}+G_0^{(2)}\Pi G_0^{(2)}+G_0^{(2)}\Pi G_0^{(2)}\Pi G_0^{(2)}+...$  the reducible diagram must be of some form. for example the 2 loop in $\phi$ theory is of the form     and the 3 loop is    how can we prove that there is not multiplicative constant say for example a 7 times the 2 loop and a 8 times the 3 loop that would invalidate the geometrical series?

In deriving the expression for the exact propagator  $$G_c^{(2)}(x_1,x_2)=[p^2-m^2+\Pi(p)]^{-1}$$   for $\phi^4$ theory all books that i know use the following argument:  $$G_c^{(2)}(x_1,x_2)=G_0^{(2)}+G_0^{(2)}\Pi G_0^{(2)}+G_0^{(2)}\Pi G_0^{(2)}\Pi G_0^{(2)}+...$$  wich is a geometric series so the formula for the exact propagator.Here  $$G_0^{(2)}$$   is the free propagator and   $$\Pi=X+Y+Z+...+W$$  is the sum of all irreducible diagrams.Here the irreducible diagrams is represented by $X,Y,Z,...,W$.  Using the path integral i can see, that  connected diagrams $D$ can be written in the form  $$D=G_0^{(2)}XG_0^{(2)}Z...G_0^{(2)}W$$  Question: But how to prove that there is no constant $C$ so that instead we have  $$D=G_0^{(2)}XG_0^{(2)}Z...G_0^{(2)}W$$  we would have  $$D=CG_0^{(2)}XG_0^{(2)}Z...G_0^{(2)}W~?$$  In the last case we would not have a geometrical serie. Can someone explain me i t please  or give me another way to derive it.


According to Microsoft, "Extension methods are a special kind of static method, but they are called as if they were instance methods on the extended type".  Is there a way to add an extension method that it called as if it was a static method? Or to do something else that has the same effect?  Edit: By which I mean "called as if it was a static method on the extended class". Sorry for the ambiguity.

I'm a fan of extension methods in C#, but haven't had any success adding an extension method to a static class, such as Console.  For example, if I want to add an extension to Console, called 'WriteBlueLine', so that I can go:  Console.WriteBlueLine("This text is blue");   I tried this by adding a local, public static method, with Console as a 'this' parameter... but no dice!      public static class Helpers {     public static void WriteBlueLine(this Console c, string text)     {         Console.ForegroundColor = ConsoleColor.Blue;         Console.WriteLine(text);         Console.ResetColor();     } }   This didn't add a 'WriteBlueLine' method to Console... am I doing it wrong? Or asking for the impossible?


I typed following command in vim to show white space characters, such as eol, tab, and space.  :set listchars=eol:$,nbsp:_,tab:>-,trail:~,extends:>,precedes:<   This file was cloned from git repository.  Indentation is setup for tabs.  How do I convert indentation to space?   50 addtask listtasks$  51 do_listtasks[nostamp] = "1"$  52 python do_listtasks() {$  53 >-import sys$  54   print('Hello World')$  55 >-for e in bb.data.keys(d):$  56 >->-if d.getVarFlag(e, 'task', False):$  57 >->->-bb.plain("%s" % e)$  58 }$

I would like to convert tab to spaces in gVim. I added the following line to my _vimrc:  set tabstop=2   It works to stop at two spaces but it still looks like one tab key is inserted (I tried to use the h key to count spaces afterwards).  I'm not sure what should I do to make gVim convert tabs to spaces?


In ,  she says this at the end of the chorus:   You’re gonna hear me roar   Why did she use the bare infinitive form of the verb roar here instead  of that verb’s ‑ing form?   You’re gonna hear me roaring   In case the context helps, the entire chorus runs like this:     I got the eye of the tiger, a fighter     Dancing through the fire.        Cause I am a champion, and you’re gonna hear me roar     Louder, louder than a lion.      Cause I am a champion, and you’re gonna hear me roar.

"Heard me [infinitive]" vs. "heard me [present participle]"             At that time, you wouldn't have heard me talk about it.   At that time, you wouldn't have heard me talking about it.         At that time, you wouldn't have heard me condemn it.   At that time, you wouldn't have heard me condemning it.         Which one of the above sentences are incorrect and why?


Let $f: \mathbb{R} \to \mathbb{R}$  be differentiable and assume that there is no $x \in \mathbb{R}$ such that $f(x)=0\ \& \ f'(x)=0$. Show that the set $S=\{x \in [0,1]\ : \ f(x)=0\}$ is finite.  Here is how I tried it.   Say that $S$ is not finite. Then, there is a atkeast countably many $ x_n$ so that $f$ is $0$ and $f'$ is nonzero at those points. i.e. $f $ attains local minima/maxima at those countably many points. Since $ f$ is continuous, local maxima/minimas keeps on exchanging. Can we somehow proceed in this way and get any contradiction on the fact that $f$ is differentiable.

Let $f:[0,1]\to \mathbb{R}$ be a differentiable function. If there do not exist any $x\in[0,1]$ such that $f(x)=f'(x)=0$, prove that $f$ has only finite number of zeros in $[0,1]$.   I'm not getting any idea how to proceed.


Unlike in random forest, I can check the oob_score_ to verify how much my model is overfitting. How can I verify this for boosted trees algorithms?  Currently, Using GBM I'm getting a accuracy of 95% on training set and 87% on test set. These numbers are after tuning on my validation set. How do I judge if this model is good enough or not?  Also, I ran 10 K-fold cv and my variance is around 1% for test set.  UPDATE: I'm using SMOTE to balance my classes

I had a job interview for a data science position. During the interview, I was asked what do I do to make sure the model is not overfitting. My first answer was to use cross-validation to assess the performance of the model. However, the interviewer said that even cross-validation cannot identify completely overfitting. Then I mentioned regularization, but the interviewer said that this could help to reduce overfitting (which I agree), but not to detect it. Are there other techniques that can be used to make sure a model is not overfitting?


I'm building an application which allows the users to embed widgets. These widgets can be any type of html/css code, for example a YouTube iframe, a Twitter embed timeline or pretty much anything else. I store user's login details in the Localstorage as a bearer token. I want to understand if a user could host a script which access the token and sends it somewhere. From what I understood if the scripts are loaded from an external domain they won't be able to access the localstorage, right? However if the user puts in the embed code something like this: <script> const str = window.localStorage.getItem('whatever')  </script>  They will be able to get it because it runs on my domain. Is there a way to disable localstorage for embed scripts? How everyone else does it? Thanks

I'm wondering if it's possible to sandbox JavaScript running in the browser to prevent access to features that are normally available to JavaScript code running in an HTML page. For example, let's say I want to provide a JavaScript API for end users to let them define event handlers to be run when "interesting events" happen, but I don't want those users to access the properties and functions of the window object. Am I able to do this? In the simplest case, let's say I want to prevent users calling alert. A couple of approaches I can think of are:  Redefine window.alert globally. I don't think this would be a valid approach because other code running in the page (i.e., stuff not authored by users in their event handlers) might want to use alert. Send the event handler code to the server to process. I'm not sure that sending the code to the server to process is the right approach, because the event handlers need to run in the context of the page.  Perhaps a solution where the server processes the user defined function and then generates a callback to be executed on the client would work? Even if that approach works, are there better ways to solve this problem?


I have html      <head>      </head>       <body>       </body>       <footer>        </footer>   now what I want is the footer stay at the very end of the page and the user should scroll to see it. would you help me please?  I tried :  footer{     position: fixed;     bottom:-100px;     height: 100px;     left: 0;     width:100%;     text-align: center; }   but setting height:100px and bottom:-100px get it hidden while I want the user to be able to scroll down to see it

I have a simple 2-column layout with a footer that clears both the right and left div in my markup.  My problem is that I can't get the footer to stay at the bottom of the page in all browsers.  It works if the content pushes the footer down, but that's not always the case.


I was writing a generator for an old assignment that made a binary tree in-order and printed it to a binary file where then I could check that the nodes were written correctly using od in bash. I noticed that when the 2 char array carrying the values for the nodes was written it ended up taking 4 bytes in comparison to the expected 2 at most. Not only that but without fail every time the third node is written that extra 2 bytes is negative filled with 0xFFFF. When I remove the char array from the Node struct and all related code to it, whatever those extra bytes were disappeared completely. I was able to complete the assignment fine by ignoring that part of the file when read back but I'm still stumped why it was ever written in the first place. I will include my code and the output from 'od -x' after running it on the output file from making a tree with 10 nodes.       int32_t loc;      char value[2];      int32_t left;      int32_t right;  }Node;  char getRandUpper() {     return (char)('A' + (rand() % 26)); }  int main(int argc, char* argv[]) {     srand((unsigned int)time(NULL));      int numOfNodes = atoi(argv[2]);     char* fileName = argv[1];      FILE* filePtr = fopen(fileName, "wb");      Node biTree[numOfNodes];      for(int i = 0; i < numOfNodes; i++) {         biTree[i].loc = i;         if((i * 2) >= numOfNodes) {             biTree[i].left = -1;             biTree[i].right = -1;         } else {             biTree[i].left = (2 * i) + 1;             biTree[i].right = (2 * i) + 2;         }         for(int j = 0; j < 2; j ++) {             biTree[i].value[j] = getRandUpper();             printf("%c", biTree[i].value[j]);             printf("size of char array: %ld bytes\n", sizeof(biTree[i].value));         }     }      fwrite(biTree, sizeof(Node), numOfNodes, filePtr);      fclose(filePtr);     return 0; }   Here is the output from od:  0000020 0001 0000 484f 0000 0003 0000 0004 0000 0000040 0002 0000 4652 ffff 0005 0000 0006 0000 0000060 0003 0000 4657 0000 0007 0000 0008 0000 0000100 0004 0000 4557 0000 0009 0000 000a 0000 0000120 0005 0000 4152 0000 ffff ffff ffff ffff 0000140 0006 0000 4a41 0000 ffff ffff ffff ffff 0000160 0007 0000 414a 0000 ffff ffff ffff ffff 0000200 0008 0000 4c41 0000 ffff ffff ffff ffff 0000220 0009 0000 504e 0000 ffff ffff ffff ffff 0000240   Anything to demystify this for myself would be appreciated. It's probably just my stupidity but who knows.

Why does the sizeof operator return a size larger for a structure than the total sizes of the structure's members?


Hi I am user of Samsung Galaxy S4, I want to know how can I change the default location of the Received files to SD Card instead of the phone storage?

I have an Android 2.3 device (Samsung Galaxy Y Duos, S6102) and want all files that I receive via bluetooth to save to my SD card.  How can I do that?


I have an invisible face in unity, and a black/flickering face in blender, I've looked it up,  but cant seem to find answer, so I have no idea how to fix it.    I have tried things like normalizing, it did fix parts of my problem, but this is the only one left and I can't seem to add a texture to the cube for some reason, as it just appears white.

I was following  on creating a watch and noticed that when I rendered the watch, some pieces were messed up.  I'm new to 3D modeling and I've just learned Blender, I can't explain it well, so here's a picture:    Other examples:     I don't know if it's a problem with my World texture, the object, or the object's texture/material, so I can't even guess how to fix it. What causes this? Is it possible to fix it?


I once thought  aren't always , but that made no sense. So here comes the topic.  Tag wiki excerpts:     : for questions regarding anonymous users      : This tag is for questions about the anonymous users, i.e. users who haven't registered on the Stack Exchange site or browsing it anonymously (not logged in).   Usage: same   has only 1/4 as much questions tagged as , so it's better that the longer one is merged into the shorter one.

On Meta Stack Exchange, there are two tags,  and . These two tags are synonyms since the tag wiki of  says "This tag is for questions regarding anonymous users". The  tag, on the other hand, doesn't have any tag wiki, but I think that regarding its name it's fairly obvious that that tag is also about anonymous users.  I think that we should keep  because although it's less popular than , its name is less ambiguous. I've seen several cases where  was used in questions about the fact that voting is anonymous that have nothing to anonymous users. Here are a few examples:        I therefore suggest that all questions about anonymous users that are tagged  should be retagged to  (I personally think that it would have been better to call it  but since we already have  we might as well use it). The  tag could be made a synonym of  or simply burninated. If  becomes a synonym of , questions tagged  that aren't about anonymous users could be retagged manually (this shouldn't be too difficult since  only has 65 questions).


Prefab structure:   MainObject (parent; prefab instance in the scene)  |-Child  |-Child  |-Triggers      |-Trigger1   MainObject has: ScriptIWantToEnable (Script) component (Disabled)  Trigger1 has: ScriptThatTriesToEnableIt (Script) component  Hello,  I'm trying to enable a script component on a prefab instance(MainObject) from a child object script component(Trigger1). For some reason though it doesn't get enabled. Run-time error shows up and the game breaks. Trigger works fine, up until the "enable" part. I checked it with the Debug.Log(). The MainObject is in the Hierarchy view already when the game starts.  Error:     NullReferenceException: Object reference not set to an instance of an   object ScriptThatTriesToEnableIt.Update () (at   Assets/Scripts/ScriptThatTriesToEnableIt.cs:30)   Part of the code in ScriptThatTriesToEnableIt that tries to enable the ScriptIWantToEnable script component of MainObject:   public class ScriptThatTriesToEnableIt : MonoBehaviour {      public GameObject MainObjectRef; //MainObject prefab instance drag&dropped in the Inspector       void Update() {          // if triggered          MainObjectRef.GetComponent<ScriptIWantToEnable>().enabled = true; //breaks here and throws the error      }  }

Since many users are facing the NullReferenceException: Object reference not set to an instance of an object error in Unity, I thought that it would be a good idea to gather from multiple source some explanation and ways to fix this error.  Symptoms I am getting the error below appearing in my console, what does it mean and how do I fix it?  NullReferenceException: Object reference not set to an instance of an object


How can I solve this problem?  Prove that for all $r\in (0,1]$, there exists a Vitali's set $V\subseteq [0,1]$ such that $\mu^{*}(V)=r$  My approach: I know that there exists a Vitali' set $V$ such that $V\subseteq [0,1]$ and I know that set is no Lebesgue-measurable,  but also I know that the value of is not known $\mu^{*}(V)$. So how can I prove that using that hypothesis we have $\mu^{*}(V)=r\in (0,1]$? I think that prove is by construction, but I don't know how can I start de construction.

Is it possible to construct a non-measurable set in $[0,1]$ of a given outer measure $x \in [0,1]$? This will probably require the axiom of choice. Does anyone have a suggestion?  Edit: I forgot to mention that the set has to be in $[0,1]$ which seemed "clear" in my head, but which obviously isn't.  Edit 2: Now it is clear that I just need a non-measurable set with outer measure 1, from that I can make any other one. I have once seen somewhere that they do this with transfinite recursion (if I recall correctly), but I don't remember where and how because I didn't know that transfinite recursion was back then.


I have finished installing RabbitMQ on Windows Server 2016, and service is running and plugins are installed however i cannot access the RabbitMQ Management Console. Can someone please assist on what could be the cause?

I have started with RabbitMQ. I have a (windows) machine on which I installed two RabbitMQ nodes as a service - I have choose the nodename, port and service name for each of them. The services are running normally (i see that they are listening in a netstat-a).  I have also installed management plugin with "rabbitmq-plugins enable rabbitmq_management" and restarted both services. But the plugin isn't running - I dont see it listening in a netstat and I can't connect to the management console via browser.  Any idea what could be wrong? Is there any log to see what is goind on?  Updated: when I do rabbitmq-plugins list i get:  c:\RabbitMq\sbin>rabbitmq-plugins list [e] amqp_client                       3.0.1 [ ] cowboy                            0.5.0-rmq3.0.1-git4b93c2d [ ] eldap                             3.0.1-gite309de4 [e] mochiweb                          2.3.1-rmq3.0.1-gitd541e9a [ ] rabbitmq_auth_backend_ldap        3.0.1 [ ] rabbitmq_auth_mechanism_ssl       3.0.1 [ ] rabbitmq_consistent_hash_exchange 3.0.1 [ ] rabbitmq_federation               3.0.1 [ ] rabbitmq_federation_management    3.0.1 [ ] rabbitmq_jsonrpc                  3.0.1 [ ] rabbitmq_jsonrpc_channel          3.0.1 [ ] rabbitmq_jsonrpc_channel_examples 3.0.1 [E] rabbitmq_management               3.0.1 [e] rabbitmq_management_agent         3.0.1 [ ] rabbitmq_management_visualiser    3.0.1 [e] rabbitmq_mochiweb                 3.0.1 [ ] rabbitmq_mqtt                     3.0.1 [ ] rabbitmq_old_federation           3.0.1 [ ] rabbitmq_shovel                   3.0.1 [ ] rabbitmq_shovel_management        3.0.1 [ ] rabbitmq_stomp                    3.0.1 [ ] rabbitmq_tracing                  3.0.1 [ ] rabbitmq_web_stomp                3.0.1 [ ] rabbitmq_web_stomp_examples       3.0.1 [ ] rfc4627_jsonrpc                   3.0.1-git7ab174b [ ] sockjs                            0.3.3-rmq3.0.1-git92d4ba4 [e] webmachine                        1.9.1-rmq3.0.1-git52e62bc


At the WineHQ site I followed the last step to install one of the available packages, I choose the stable branch and the command is sudo apt install --install-recommends winehq-stable, it unpacking some wine file and end up getting this error: dpkg: error processing archive /var/cache/apt/archives/wine-stable-amd64_5.0.2~ focal_amd64.deb (--unpack):  cannot copy extracted data for './opt/wine-stable/lib64/wine/d3dx9_24.dll' to  '/opt/wine-stable/lib64/wine/d3dx9_24.dll.dpkg-new': failed to write (No space  left on device) No apport report written because the error message indicates a disk full error         d pkg-deb: error: paste subprocess was killed by signal (Broken pipe) Errors were encountered while processing:  /var/cache/apt/archives/wine-stable-amd64_5.0.2~focal_amd64.deb E: Sub-process /usr/bin/dpkg returned an error code (1)

My Ubuntu cloud server has left only 900MB of disk space.   I'll just empty the directory /tmp and wondering if there is any other location to clean up.


I have ncurses apps (say, aptitude) working nice in plain xterm (or gnome-terminal, or any other terminal I've tried), but if I run it inside tmux session, screen isn't properly refreshed while I do some navigation through the menu.  Example screenshot:   (full resolution: )  The same happens with other ncurses apps inside tmux: say, . And again, without tmux they work nice.  How to make it work correctly in tmux too?  (OS is Linux Mint 13, if that does matter)

The problem:   I open a terminal (in Linux Mint, so mate-terminal) zsh is the shell Then I run tmux Edit a file with nano Scroll up and down that file with the cursor Issue: When scrolling down in nano, only the bottom half of the terminal window gets refreshed Issue: When scrolling up in nano, only the top half of the terminal windo gets refreshed   The complete nano view of file does not get refreshed in my terminal window when scrolling. Any tips?  Edit: my .tmux.conf  It seems that this line specifically is the culprit (as commenting it out fixes the problem):  set -g default-terminal "xterm-256color"   I'm pretty sure I added that line because I have issues even running nano during an SSH session.  Here is the full file:  set-option -g default-shell /bin/zsh  # Make sure tmux knows we're using 256 colours, for # correct colourised output set -g default-terminal "xterm-256color"  # The following were marked as "unknown", so # I do know what I'm doing wrong. #set -g mode-mouse on #setw -g mouse-select-window on #setw -g mouse-select-pane on  # Attempting to stop "alert" sound upon startup # but none of these are working... set-option bell-on-alert off set-option bell-action none set-option visual-bell off


$2730=2\cdot3\cdot5\cdot7\cdot13$  $n^{13}-n=n(n-1)(n+1)(n^2+1)(n^8+n^4+1)$  Divisibility by $2$ and $3$ follows from the product of two and three successive terms.  Divisibility by $5$ follows from Fermat's little theorem: $$n^{5-1}\equiv1(\mod 5)\Rightarrow 5|(n^{13}-n)=(n^4-1)(n^8+n^4+1)$$  How to prove divisibility by $7$ and $13$?

Show that $2730\mid n^{13}-n,\;\;\forall n\in\mathbb{N}$   I tried, $2730=13\cdot5\cdot7\cdot3\cdot2$  We have $13\mid n^{13}-n$, by Fermat's Little Theorem.  We have $2\mid n^{13}-n$, by if $n$ even then $n^{13}-n$ too is even; if $n$ is odd $n^{13}-n$ is odd.  And the numbers $5$ and $7$, how to proceed?


Find ab if  $$ \int \frac{dx}{e^x+1}=ax+b\ln\left(e^x+1\right)+C $$

How do I solve evaluate $$\int \frac{\mathrm{d}x}{e^x + 1}\ ?$$  I know that I have to use $u$ substitution but I can't seem to find something to substitute with.


I like most computer users, have many Windows based programs. Can these be operated under Ubuntu and if so what is required. Thanks for your help Chris

Can .exe and .msi files (Windows software) be installed in Ubuntu?


Is there a word for a pair of words that would appear to be antonyms from their construction, but actually have the same or similar meanings?  For example, brief / debrief.  From :     A spokeswoman for the European commission said Barnier would debrief ambassadors and MEPs on the European parliament’s Brexit steering group.   The meaning wouldn't change much if it instead said:     A spokeswoman for the European commission said Barnier would brief ambassadors and MEPs on the European parliament’s Brexit steering group.   One can debate on a subtle change of meaning and as to whether the second use is actually correct (some dictionaries state that the verb brief means to inform ones superiors specifically), but we can probably agree that debrief is not, in this context, the antonym of brief, despite the prefix de- usually indicating a reversal (such as in decode, decompress, demystify, detoxicate).    Another example may be flammable and inflammable.  The prefix in- often indicates a reversal (incredible, invisible, inalienable), but inflammable is rather a stronger version of flammable (intoxicate is not an antonym of toxicate, but doesn't have a similar meaning either).  Is there a word for the situation where two words would appear to be antonyms but aren't?  I was thinking of , but that is a single word having two opposite meanings.  Here, we have two seemingly opposite words having (almost) the same meaning, which is related but not quite the same.

The words flammable and inflammable mean the same thing, but (to someone unfamiliar with their meaning) appear to be opposites (because of the "in" prefix). Is there a name for such word pairs that appear to be opposites but actually mean the same thing? A few other examples are ravel/unravel, regardless/irregardless, radiation/irradiation, incite/excite, culpatory/inculpatory, press/depress, to/unto, part/depart, fat chance/slim chance, thaw/dethaw/unthaw, candescent/ incandescent, canny/uncanny, dead/undead, write up/write down, valuable/invaluable, habitable/inhabitable


The use of Final keyword inside the method argument puzzles me  public void helloWorld(String str) {  }   public void helloWorld(Final String str) {  }  What is the differences between them?

I can't understand where the final keyword is really handy when it is used on method parameters.    If we exclude the usage of anonymous classes, readability and intent declaration then it seems almost worthless to me.   Enforcing that some data remains constant is not as strong as it seems.    If the parameter is a primitive then it will have no effect since the parameter is passed to the method as a value and changing it will have no effect outside the scope.  If we are passing a parameter by reference, then the reference itself is a local variable and if the reference is changed from within the method, that would not have any effect from outside of the method scope.    Consider the simple test example below. This test passes although the method changed the value of the reference given to it, it has no effect.  public void testNullify() {     Collection<Integer> c  = new ArrayList<Integer>();           nullify(c);     assertNotNull(c);            final Collection<Integer> c1 = c;     assertTrue(c1.equals(c));     change(c);     assertTrue(c1.equals(c)); }  private void change(Collection<Integer> c) {     c = new ArrayList<Integer>(); }  public void nullify(Collection<?> t) {     t = null; }


This is not a duplicate question. There is an answer posted in the question. Hope it can help.  There are two doubles with the same value with decimals.  (Sorry, this is not a good case. because it will return false sometimes, but I can't find the case. If you try this case, it may not have any problem. So don't waste time to test it.)  double a = 0.70448; double b = 0.70441;   I want to compare them with only 4 decimals.  I have this helper function to round them down to 4 decimals first.  public static double RoundDown(this double value, int decimals) {     var multiplier = Math.Pow(10, decimals);     return Math.Floor(value * multiplier) / multiplier; }   And then I want to check if a is larger than b like this: RoundDown(a, 4) > RoundDown(b, 4)  Sometimes, for some cases, it will return true even they look equal. I understand very well this is floating issue, so I would like to know if there any elegant solution to compare them.  Updates:  I have tried to multiply it and compare them in integer. However, for this solution, I need to handle double infinity and NAN.      private static CompareResult Compare(double a, double b, double decimals = 0)     {         var multiplier = Math.Pow(10, decimals);         var aInt = Convert.ToInt32(a * multiplier);         var bInt = Convert.ToInt32(b * multiplier);         return aInt > bInt ? CompareResult.Greater : aInt < bInt ? CompareResult.Less : CompareResult.Equal;     }      private enum CompareResult     {         Greater,         Less,         Equal     }   System.OverflowException is thrown if one of the double is larger than int max or infinity. Also, this is not an elegant way to compare double.  Importants:   I am not going to round down with x significant figures. I have already provide this solution in my question, my question is: Even round down to x significant figures, it will return true when comparing them.  Again  I am not finding a way to round down or truncate the doubles to x significant digits. I have no problem on this part.  Answer  Thanks for @m88 answer. But it still cannot solve my problem. I finally solve this issue using sigma. (Reference: .)  Thanks to some people misunderstand the problem and vote it as a duplicated question. I can't post my answer for others facing the same problem. So I post the answer in my question. I hope it can help others.  public static int CompareTo(this double value1, double value2, int decimals) {     var diff = value1 - value2;     var sigma = Math.Pow(10, -decimals - 1);     return Math.Abs(diff) < sigma ? 0 : diff > 0 ? 1 : -1; }

If I have a double (234.004223), etc., I would like to round this to x significant digits in C#.  So far I can only find ways to round to x decimal places, but this simply removes the precision if there are any 0s in the number.  For example, 0.086 to one decimal place becomes 0.1, but I would like it to stay at 0.08.


I've got two displays arranged like so:    I'd like my dock to appear along the bottom of my primary (horizontal) screen but show on the left of my secondary (vertical) screen.  Is there any way to do this on MacOS?

Is it possible to have the dock in different positions in different desktops? In particular I'd like to change the settings between a normal desktop and a desktop where there's an app at full screen. In this way I'd keep the dock in lower side of the desktop when there's an app at full screen and vertically on the left side during normal use.  I have this problem that, sicne I usually have the dock vertically on the left, it pops out everytime i go to the far left in an app I'm using with full screen, and using this app I have to move the mouse to the left quite often.


I would say British English seems to adhere to English grammar books that I learned in school more than American English.  For example, I was taught that we use present perfect with "ever" because the time is unspecified or something which happened in the past which is important now.  See  say:     Present perfect simple: uses      We use the present perfect simple to refer to events in the past but   which connect to the present.      We often use present perfect for talking about something which   happened in the past which is important now.      we often use general time expressions like ever, never, before, in my   life, so far, up until now with this use of the present perfect   simple:      We often use ever, not … ever and never when we talk about   experiences:      Have you ever tried to write your name and address with your left hand?      American English      In American English the past simple is often used instead of the   present perfect simple, often with already and yet.      American English Did you eat (yet)? Did you finish (already)?      British English Have you eaten (yet)? Have you finished (already)?    confirms this:     The Present Perfect Tense in British and American English      British and American grammar differences – present perfect vs. simple past      In American and British English, we can also use ‘just’ with the   simple past to talk about recent events. So what’s the difference   about the way American and British people use ‘just’? When we’re   giving news in British English we generally use the present perfect.      Oh, your mother’s just called.       Oh, what did she want?      When we’re giving news in American English, we often use the simple   past.      Your sister just called.       Oh really? What did she want?      So both these sentences are possible in both varieties. It’s just that   we use the present perfect more frequently in British English.      The words ‘yet’ and ‘already’ indicate a time up to now or until now.      That relation to the present time means we commonly use them with the   present perfect. That’s true in both British and American English. In   American English, especially spoken English, you’ll often hear us use   these words with the simple past, too.      I’m going outside to practice soccer.       Wait a sec.       Did you do your homework yet?      Yeah, I already did it.       OK.      In British English, these sentences would be unusual. With ‘yet’ and   ‘already’ we usually use the present perfect, not the simple past. So   when do Americans use the present perfect and when do they use the   simple past? In written English and when we’re speaking carefully, we   often use the present perfect with ‘yet’ and ‘already’. But when we’re   speaking informally, we often use the simple past. ‘Did you do it   yet?’ sounds a little more informal than ‘Have you done it yet?’,   especially if we use the less careful pronunciation ‘Did ja do it yet?.   And there’s something else. My theory is ‘Did you do it yet?’ can   sound just a little more urgent in American English than ‘Have you   done it yet?’   And I guess that usage may apply to "ever" as well  Have you ever watched the film? ( we use present perfect because we don't know the time the that person watched the film or the specific time that that action happened is not important or its result is important now, ie I just want to know if you have watched it, the time is not important)  But American people will say:  Did you ever watch the film? (I feel strange when hearing it, why would the asker want to know the specific time right at the beginning)  Is that how American people say daily? or  American grammar is not as strict as British English?

According to  the use of past simple and present perfect is quite strict in British English, while in American English you can normally use simple past instead of present perfect:  In British English, the use of Simple Past and Present Perfect is quite strict. As soon as a time expression in the past is given, you have to use Simple Past. If there are no signal words, you must decide if we just talk about an action in the past or if its consequence in the present is important. Note that the following explanations and exercises refer to British English only. In American English, you can normally use Simple Past instead of Present Perfect. We cannot accept this in our exercises, however, as this would lead to confusions amongst those who have to learn the differences.  In the case of the noun to choose, if I'm correct, the difference between "did choose" and "have chosen"; the second is more definitive than the last. Can somebody give me a clear example of where the British use diverges from American English? As a non-native speaker, I find it hard to see/feel the difference between its use in British- and American English respectively.


Can i port Ubuntu Touch on samsung galaxy s2 plus i9105p?  thanks

I would like to port Ubuntu Touch to a device that is currently not supported. What are the requirements for doing this and where do I begin?