Here is where i got a problem: When i want ot fire button Marchewkaim getting error null pointer exception:  public class MainFrame extends JFrame { public static  void Draw() {     mp.repaint(); } private static final long serialVersionUID = 1L; private JPanel jContentPane = null; static private MyPanel mp = null;  /**  * This method initializes mp     *    * @return MyPanel    */ private MyPanel getMp() {     if (mp == null) {         mp = new MyPanel();         mp.setLayout(null);     }     return mp; }  /**  * @param args  */ public static void main(String[] args) {      // TODO Auto-generated method stub     SwingUtilities.invokeLater(new Runnable() {         public void run() {             MainFrame thisClass = new MainFrame();             thisClass.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);             thisClass.setVisible(true);          }     });    }  /**  * This is the default constructor  */ public MainFrame() {     super();     initialize(); }  /**  * This method initializes this  *   * @return void  */ private JPanel getJContentPane() {     if (jContentPane == null) {         jContentPane = new JPanel();         jContentPane.setLayout(new CardLayout(0, 0));      }     return jContentPane; } private void initialize() {      this.setSize(668, 402);     this.setContentPane(getJContentPane());     this.setTitle("JFrame");     JPanel panel = new JPanel();     panel.setLayout(null);     this.getContentPane().add(panel, "Main");     panel.setVisible(true);     JButton btnMarchewka = new JButton("Marchewka");     btnMarchewka.setBounds(12, 25, 113, 49);     panel.add(btnMarchewka);      JButton btnArbuz = new JButton("Arbuz");     btnArbuz.setBounds(12, 87, 113, 49);     panel.add(btnArbuz);      JButton btnUsun = new JButton("Usun ostatni");     btnUsun.setBounds(12, 149, 113, 49);     panel.add(btnUsun);     btnMarchewka.addActionListener(new ActionListener() {         public void actionPerformed(ActionEvent e)          {             Draw();         }     });  }  /**  * This method initializes jContentPane  *   * @return javax.swing.JPanel  */   }  //  @jve:decl-index=0:visual-constraint="10,10"   Another class  public class MyPanel extends JPanel {  public GObject c;  public GObject w; //  @jve:decl-index=0: private static final long serialVersionUID = 1L; public List<GObject> list= new ArrayList<GObject>(); /**  * This is the default constructor  */ public MyPanel() {     super();     initialize(); } public void addCarrot() {     GObject[] c=new GObject[list.size()+1];     c[list.size()]=new Carrot();     list.add(c[list.size()]);     MainFrame.Draw();     } public void addWatermelon() {     GObject[] w=new Watermelon[list.size()+1];     w[list.size()]=new Watermelon();     list.add(w[list.size()]);      MainFrame.Draw();     }    public void remove()    {    list.remove(list.size()-1);      MainFrame.Draw();   }   /**  * This method initializes this  *   * @return void  */ private void initialize() {     this.setSize(400, 400);     this.setLayout(null); } @Override protected void paintComponent(Graphics arg0) {     // TODO Auto-generated method stub     super.paintComponent(arg0);     if             (list!=null){     for(int i=0;i<list.size();i++)     {         list.get(i).drawMe(arg0);     }     } }   }   I tried to resolve this error on my own but i cant find where im pointing at nothing. Doing this for 6 hrs and im sick and tired.Im looking for some tips .


For $a, b, c$ is the length of three sides of a triangle. Prove that $\left|\frac{a-b}{a+b}+\frac{b-c}{b+c}+\frac{c-a}{c+a}\right|<\frac{1}{8}$

For $a, b, c$ is the length of three sides of a triangle. Prove that $$\left|\frac{a-b}{a+b}+\frac{b-c}{b+c}+\frac{c-a}{c+a}\right|<\frac{1}{8}$$


How can I remove the references name from the list of table of contents. I am writing the Thesis

List of Figures  Figure 2.1  Linear System of Membrane and coil (Carlsson 2009) . . . . . . . . . .   6  Figure 2.2  The Six Degrees of Freedom in 3D (McLean 2016) . . . . . . . . . . . .   9  I want to remove my \cite from all figures name in TOC only. Not from the figure heading in chapters.


Is it possible to introduce an own table of contents in LaTeX? I would like to introduce an own tag, to define some terms in my document. At the end of the document I would like to automatically generate a list of defined terms, with links to the page, where the term was defined.


Does a simulacrum'd creature's statblock include its personality and knowledge/memories?

Basis: In the clone spell, it states clearly that      The clone is physically identical to the original and has the same personality, memories, and abilities, but none of the original’s equipment.   while simulacrum does not have this text. Simulacrum does state, however, that     Otherwise, the illusion uses all the statistics of the creature it duplicates, except that it is a construct.   The 5e SRD definition of "statistics" also refers to that as its "stat block", which consists of features like its type, race, ability scores, features, and notably, its alignment. And according to the suggested post (), it only makes mention of alignment without addressing personality or memories and does not provide me with a satisfactorily specific answer.  By the language of clone and true polymorph as examples, does a sim'd creature's statblock include its current knowledge/memories and personality?


I am trying to Insert Guest Additions CD Image and then run VBoxLinuxAdditions.run  I am new to Ubuntu and trying to learn. I am running Ubuntu 18.04LTS through Oracle VM v6.04r. My host laptop is running Windows 10 Pro. So I went to Devices>Insert Guest Additions CD Image. That created Vbox_GAs_6.0.4 on my Ubuntu Desktop. Then I tried to run VBoxLinuxAdditions.run through the terminal and go the following messages.  arijitpc@arijitpc-VirtualBox:/media/arijitpc/VBox_GAs_6.0.4$ sudo ./VBoxLinuxAdditions.run [sudo] password for arijitpc: Verifying archive integrity... All good. Uncompressing VirtualBox 6.0.4 Guest Additions for Linux........ VirtualBox Guest Additions installer Removing installed version 6.0.4 of VirtualBox Guest Additions... Copying additional installer modules ... Installing additional modules ... VirtualBox Guest Additions: Building the VirtualBox Guest Additions kernel modules.  This may take a while. VirtualBox Guest Additions: To build modules for other installed kernels, run VirtualBox Guest Additions:   /sbin/rcvboxadd quicksetup <version> VirtualBox Guest Additions: Building the modules for kernel 4.18.0-18-generic.  This system is currently not set up to build kernel modules. Please install the gcc make perl packages from your distribution. VirtualBox Guest Additions: Running kernel modules will not be replaced until the system is restarted VirtualBox Guest Additions: Starting. VirtualBox Guest Additions: Building the modules for kernel 4.18.0-18-generic.  **This system is currently not set up to build kernel modules. Please install the gcc make perl packages from your distribution.**   Request you to please help me as to what should be done. There are so many information out there, most of which are not working, its confusing. Also request to please provide me the commands I need to run on the terminal as I am mostly not familiar with most lingo in Ubuntu/ Linux environment.


Why do i see more steam coming out from the vessel containing water after i turned off the stove?

It is a little observation i did when i was boiling the water.   what i observe is that when i turned off the stove on which the water was boiling i could see more steam coming out from it  than the steam which was coming before the stove was turned off i.e. the amount of steam coming out per second was more  when the flames which waere giving heat to the water is turned off   Why is that so?


I have a written thesis, as my Final year project. I have submitted in university.   but now i want to make it professionally mine.   I want to publish it some where but i don't have such kind of experience before. I am total Rookie in this field.  Any Expert Opinion?  Note: Thesis in About "Handwriting Recognition "


Does Windows 7 allow auto-login with a stored password, like TweakUI did?

The TweakUI powertoy for Windows XP had an option to auto-login. It stored your password and did the login for you. This was useful, since you kept password protection, but had login programs loaded when you first booted.  When you switched users or hibernated, it would still ask for a password, which is the desired behavior.  Is there a way of doing this in Windows 7?


Do RSA keys contain a checksum mechanism?

I'm new to cryptography, and I was making an experiment a few minutes ago, but I want to have some deeper knowledge about RSA public and private keys.  I have a set of keys  One begins with   -----BEGIN RSA PRIVATE KEY----- MIIBOgIBAAJBAOlnH1jZ2YLfWuYMop1a4N9jsUPK...... -----END RSA PRIVATE KEY-----   and another with  -----BEGIN PUBLIC KEY----- MFowDQYJKoZIhvcNAQEBBQADSQA.... -----END PUBLIC KEY-----   I've parsed them using Java and I can make use of them, as RSA private and public keys respectively.  But the question I have is....   Are there some checksum mechanisms built into RSA keys ?   I ask this because, I'd like to know what happens if, by error or intentional, one or more characters from the encoded PEM are modified. Does this breaks the key ? Or changes the key internally, without breaking it ?


Can't find my bootable USB as an option in the UEFI options

I'm using a Dell laptop with Ubuntu 16.04 LTS.  I tried to make a bootable USB after downloading the Windows 10 ISO file, but it doesn't appear as an option in the UEFI bootable screen.  I didn't use woeusb or any other program as I couldn't install them. I just made it using the Disks utility, then I formatted it as FAT32 then used **Restore Disk Image and restored the Windows ISO file. Is this a correct method of making a bootable USB?


When I compile my tex file, it returns a wrong, "File `microtype.sty' not found. \usepackage"  How can I solve it?


I'm trying to hook up dual monitors (Samsung CF390) to my MacBook Pro, but when I do, I only have the desktop image projecting on both screens. When I go into Settings > Display, the "Arrangement" option isn't available.  I have both monitors' HDMI cables running through 1 USB-C to HDMI adapter. (The adapter has two ports.)  Is the solution to this problem having two adapters? My thinking is even though the adapter has 2 ports, the MacBook hardware or software can't Fully make use of both displays.   What can I change to get three total displays working on macOS High Sierra (10.13.x)?


Change the frame size of UISearchBar TextField?

I am unable to set frame of UISearchBarTextField.... Should I create my own Search Bar or Is there a way to do the above?


Bounty completed notice (and grace period notification email) happen before bounty ends

The email notice that bounties have ended and are entering the grace period as well as the inbox notification seem to happen before the bounty period is actually over.    Several similar requests marked as bugs have been turned away as "by design", but I believe this is kind of silly. This keeps coming up and should be fixed.  If the timing mechanism isn't going to get fixed so that it actually sends notices at a consistent time in relation to the end of the period, then at least update the copy. If you don't know whether the period is up or not, don't pretend like you do. Instead of "has completed" say "completes today at HH:MM UTC" and let the user figure it out when they follow the link. But even if the timing mechanism doesn't know ahead of time you should be able to query the end timestamp and regenerate the string based on the current time. There shouldn't be any reason the notification can't read just like the page does at the time the notification is sent.


Does weak topology preserve topological vector space structure?

Consider a topological vector space $X$ (not necessarily normed or metrisable or anything). Its topological dual is a well defined set of linear maps. With this in place, the weak topology is defined as the coarsest topology on $X$ such that all of the dual still consists only of continuous linear forms. It it possible that the weak topology be so coarse that $X$ equipped with its weak topology is no longer a topological vector space ?


Portable Speaker Powered by Battery and Power Supply Separately but Can Charge the Battery From the Same Power Supply

I'm building a portable speaker using a PAM8403 amp, 3.7v battery, and a battery charging module, all powered by USB input. What I want to do is be able to switch between   1) charging the battery from USB input  2) Power amp just from 3.7v battery.  3) power amp just from USB input(So when it is plugged into the wall it runs 5v. to the amp and gives it more power than when running off the battery).  I can't figure out how to do this without using switch for the battery, the power input, and to turn it all on and off. so many switches would be very user friendly. Is there a way to do this with less switches?


Using Remote Desktop to connect to different computers behind same IP

I'm trying to connect my computer from home to two computers in my office. The office has a router and I already forward the port for computer A. I can successfully connect to my computer A at my home by using static ip address. However, I am not sure how to connect to computer B since both computers use the same static IP address that is given by my ISP.  For example, at my home computer's Remote Connection box, I type 7x.8x.1xx.2xx. That IP address is for both computers.   I'm not sure how to distinguish the computer A and computer B. Any thoughts?


How can I color the output of this MWE like the screenshot?  \documentclass{book} \usepackage{tikz}  \begin{document} \begin{center} \begin{tikzpicture} \draw [thick] (3.25,-2) circle (1.5cm)      node[right=.7cm, above=.4cm] {$A$}; \draw [thick] (2.5,-3.5) circle (1.5cm)     node[left=.7cm,] {$B$}; \draw [thick] (4,-3.5) circle (1.5cm)       node[right=.7cm] {$C$}; \draw [thick](0,0) rectangle (6.5,-5.5)     node[left=6cm, above=.3cm] {$M$}; \end{tikzpicture} \end{center} \end{document}


Probability that all cards have been drawn

Let's say, I have a deck of $m$ cards from which I will draw $n$ cards at random, watch them and put them back in the deck. I want to know; what is the change after $k$ draws, that I have seen all cards in the deck.  It is actually a variant to the problem described , however in this and  case the number of items per draw is only one.  simulation  I made a simulation where the decksize is 10 and the number of cards each draw is 4, the results are plotted below ().   personal attempt  I only got to the point to calculate the probability that a single card is not in a single draw:  $\displaystyle P = (1 - \frac{1}{m})(1 - \frac{1}{m-1})(1 - \frac{1}{m-2})(1 - \frac{1}{m-3}) = \sum_{i=1}^n (1 - \frac{1}{m-i+1}) $


Is using the wrong mA on a power supply dangerous?

I recently moved and didn't properly mark a couple of power supplies before I packed them up. I have a turntable and a pre-amplifier that both use 15v power supplies. One of the two power supplies outputs 15v 250mA and the other outputs 15v 550mA. The documentation for both devices just says "15v". I have done an exhaustive search online to see if I can find which adaptor belongs to which device, and have come up with nothing.   I'm at the point where I'm going to have to just guess. But both of these components are fairly expensive, so I'm concerned about using the wrong power supply and damaging the device. I'm not understanding exactly what the difference in mA means, and what is the risk of plugging the wrong one in.


Installing Ubuntu on a SSD and HDD system

So I have this 128 GB SSD and a 1 TB HDD. And I plan to install Ubuntu on this system that uses them.  Now all the info that I have found in here about similar problems, are usually with limited SSD space, but mine is pretty big. It is a Samsung 840 Pro 128 GB.  So my question is, what would be the intelligent way of partitioning my system in this case?   Obviously the / will go on SSD. Then /home and /swap will go on HDD. But what else? Should I care about "/tmp" and "/var" also and move them on my HDD? How much size would it be smart to allocate for them then?


I read the original , I understand, but I don't do Python.  How would I "reset" my settings as shown? I've had trouble with these forever, so my Solid lighting as I work is bizarre. Even with a new startup they're kaflooey.  Added bonus: How to "put back" the settings I have now if I screw up?


Would you say 'yes, neither do I' / 'yes, me neither'?

My question does not have to do with the correctness/incorrectness of 'neither do I'/'me neither', but with the presence of the 'yes' (or 'yeah', which is how it most often 'comes out' for me) at the beginning.  If someone were to say:     I love chocolate.   I'd naturally answer (orally) one of the two:     Yeah, so do I. / Yeah, me too.   But if someone were to say:     I don't like driving.   Would it be normal to answer:     Yeah, neither do I. / Yeah, me neither.   Or with it be best to say:     No, neither do I. / No, me neither.     I do not understand why my question was marked as a duplicate. My question is not about the personal pronoun (I or me) but about the adverbs (Yes/Yeah or No). I do state in the first paragraph that my question concerns "the presence of the 'yes' (...) at the beginning.", whereas the question I'm supposedly 'duplicating' is clearly focused on the personal pronoun.  I shall edit to make the words I'm concerned with in bold to see if that clarifies that I'm not interested in the pronouns.


my MacBook Pro hard drive died (after dropping) I can see the disk when I book from DVD but I don't want to format not to lose data.  What is the best way to recover data? (what hardware and software if any I need)  I have other IMac and Windows computers


How can I make an indented cube without using a boolean operation?

As the title says, how can I make this shape without resorting to a Boolean operation?    This is obviously a very simple example, but I find myself needing to do something like this relatively often when modelling.  Despite using Blender for a couple of years, and considering myself an intermediate to possibly advanced user, I still know of no easy way to make this kind of indentation in an object.  Obviously, if you are looking to make an indentation in the middle of the surface, you can simply select a face and extrude down. As you will know, this does not work at the edge of the surface.  I can create this shape using loop cuts, deleting the faces and then using snap to edge to extrude the edges down to the same level (and then filling in the faces), but it feels cumbersome and a lot of work for what feels like it should be very simple.


c# compare two numbers got from two files

in c# i need to compare 2 numbers one from a local file, and one another from a downloaded file like a Patcher.  if I use Streamreader c# sad to me that he can't convert string into INT.  are there a solution for this? file a contains the value "1" , the file b contains the value "2"  so if b>a then download the new files catch from another updater file.  thanks


For example: Space (jump) + WASD (move) and  R (Sprint). In this case I can sprint, but I can't jump at the same time.  But if I try Space + WASD + another key like F it does work.  I have a Sharkoon Skiller Pro (it is made for gaming), and sticky keys are off.  PS: This is annoying in games like Minecraft.


I am seeing some very strange results when using du on some of my folders. For example: #cd /storage/main_folder  #du -h --max-depth=2 subfolder1 | grep subfolder2   1.8G    subfolder1/subfolder2/subfolder31 5.3G    subfolder1/subfolder2/subfolder32 352M    subfolder1/subfolder2/subfolder33 76K     subfolder1/subfolder2/subfolder34 1.8G    subfolder1/subfolder2/subfolder35 4.0M    subfolder1/subfolder2/subfolder36 301M    subfolder1/subfolder2/subfolder37 9.4G    subfolder1/subfolder2  # du -h --max-depth=1 subfolder1/subfolder2  1.8G    subfolder1/subfolder2/subfolder31 5.3G    subfolder1/subfolder2/subfolder32 352M    subfolder1/subfolder2/subfolder33 96G     subfolder1/subfolder2/subfolder34 1.8G    subfolder1/subfolder2/subfolder35 4.0M    subfolder1/subfolder2/subfolder36 301M    subfolder1/subfolder2/subfolder37 106G    subfolder1/subfolder2  As far a I can tell, there are no links or special files in subfolder2. The disk is a local RAID volume, ext4, mounted with rw,noatime,nodiratime,stripe=64 . What could be causing this, and what can I do to fix the problem, and get the correct results? Thank you! [ Edit, because I received a link to  : I am aware of apparent size vs block size. But in this case, note that:  subfolder34 shows up as 76K in one output, and 96G in the other. Too big a difference to be explained by apparent size... I am using the exact same du command, the only difference is the working directory when running the command. So we can exclude differences due to the way different utilities compute sizes ]


Almost all uncertainties (for example the position-momentum uncertainty or time-energy uncertainty) are greater than ${\hbar}/{2} $. But what is the derivation of this  by Heisenberg? Is there any sort of intuitive explanation behind the magnitude of uncertainty? I know why uncertainty happens but I do not why the value. It'd be great if somebody could provide a simple explanation.  $$  \mathrm{uncertainty} \geq  \frac{\hbar}{2} $$


I am working on a registration form. I am trying to find the friendliest way to organize the content. I would appreciate if you could tell me: 1. Which layout you find better 2. If double checking the password is essential 3. Any comments or suggestions are welcomed and appreciated too :)


Quantum computing w.r.t. the many-worlds theory

Quantum algorithms are inherently probabilistic. Let's say I run Shor's factoring algorithm on some number. There's a chance that the output I observe is incorrect. Does the many-worlds theory suggest that I'm simply in a universe where the output happened to be wrong? Because the probability of error is slim, does that mean the vast majority of universes realize a correct execution of the algorithm?  Edit: Thanks to  for pointing me to  which fully explores my question. Also, a big thanks to everyone who commented here! The questions raised and resources raised have only helped to enhance my curiosity about the subject.


Do different regions of the world have different names for spells?

It is well established that there is an international wizard in community of which there are many witches and wizards of varying nationalities. It think that just as there are varying traditions and normalities that there would also be varying incantations to cast spells with or without a wand. We see the spells in some kind of Latin form, and it makes sense as the book is written in British English and Latin is the root language for that and many other European languages. But what about places like India, who have Sanskrit as a kind of base language, or Old Chinese in China, and maybe Ancient Egyptian for Egypt (though I think that a select few Egyptian witches and wizards would study that, most people using Old Arabic instead)? So, do other parts of the world have different incantations for spells?


Is 45 mins enough in Newark airport terminal C to change the plane for connecting flight?

My flight will arrive Newark at 19:49 Terminal C and my connectiong internation flight will start at 20:35 Terminal C. There is no change in terminal, I just have to change the plane. Is this enough to manage? I am worried because layover is just 45 mins.


I have a dynamic form that I want to append some other html in, but when I want to use the event of my appended html I should include that script in that first script but also I want to add another html in the second script but I don't know how to deal with quotation tags:        $(document).ready(function(){     $("#registerNums").on('click',function(){       var inputnums = parseInt($("#inputnums").val());       alert(inputnums);       var outputnums = parseInt($("#outputnums").val());       alert(outputnums);       var rulenums = parseInt($("#rulenums").val());       for(var i=1; i < inputnums + 1; i++){         var inputmems =         '
'+           '
'+             '
'+               'Enter the number of your input'+ i +' membership functions:'+               '<input type="text" class="form-control" id="inputmems'+ i +'" name="inputmems'+ i +'" placeholder="Enter inputmems">'+             '
'+             '
'+               'Enter the name of your input'+ i +' membership functions:'+               '<input type="text" class="form-control" id="inputname'+ i +'" name="inputname'+ i +'" placeholder="Enter inputname">'+             '
'+             '
'+               'Enter the range of your input'+ i +' membership functions:'+               '<input type="text" class="form-control" id="inputrange'+ i +'" name="inputrange'+ i +'" placeholder="Enter inputrange">'+             '
'+             '
'+               '<input type="button" class="btn btn-primary" id="registerMems" value="register mems">'+               '


I am  using other language to save that in the  phpmyadmin, but it's working like that :  mysqli_query($con,"SELECT * FROM list"); mysqli_query($con,"INSERT INTO list (title,content)  VALUES ('other language TITLE', 'other language CONTENT ')");   and it's showing in phpmyadmin like that :                                                                                áƒ•áƒáƒšáƒ”áƒ áƒ˜ áƒ’áƒ”áƒšáƒ‘áƒáƒ®áƒ˜áƒáƒœáƒ   any solutions please?


Adding custom theme template to custom post type

I've created a new custom post type called MemberPost and want it to follow a slightly different template to my main index (which is where main news is kept). I've created a custom post type and inserted this into my functions.php.  add_filter('excerpt_more', 'new_excerpt_more');  add_action( 'init', 'register_cpt_member_post' );  function register_cpt_member_post() {  $labels = array(     'name' => __( 'MemberPost', 'member-post' ),     'singular_name' => __( 'MemberPost', 'member-post' ),     'add_new' => __( 'Add New', 'member-post' ),     'add_new_item' => __( 'Add New MemberPost', 'member-post' ),     'edit_item' => __( 'Edit MemberPost', 'member-post' ),     'new_item' => __( 'New MemberPost', 'member-post' ),     'view_item' => __( 'View MemberPost', 'member-post' ),     'search_items' => __( 'Search MemberPost', 'member-post' ),     'not_found' => __( 'No memberpost found', 'member-post' ),     'not_found_in_trash' => __( 'No memberpost found in Trash', 'member-post' ),     'parent_item_colon' => __( 'Parent MemberPost:', 'member-post' ),     'menu_name' => __( 'MemberPost', 'member-post' ), );  $args = array(     'labels' => $labels,     'hierarchical' => false,     'description' => 'Post containing the months member content',     'supports' => array( 'editor', 'title', 'thumbnail'),     'public' => false,     'show_ui' => true,     'show_in_menu' => true,     'menu_position' => 5,     'show_in_nav_menus' => true,     'publicly_queryable' => true,     'exclude_from_search' => true,     'has_archive' => true,     'query_var' => true,     'can_export' => true,     'rewrite' => array('slug' => 'member-post'),     'capability_type' => 'post' );  register_post_type( 'member_post', $args ); flush_rewrite_rules(); }   I then created the single-memberPost.php but I can't get the theme to use this custom post template.


I have noticed that some Linux Servers in Network takes long time to connect using ssh.   Situations:   There are two situations I have faced:   On some servers some times it takes a long time to ask for password but on other servers When I insert the password it doesn't respond . And after some time say 20 0r 30 seconds it just say Connection Closed   Detail for 1 case:  debug1: Authentications that can continue: publickey,gssapi-with-mic,password debug1: Next authentication method: gssapi-with-mic debug1: Unspecified GSS failure.  Minor code may provide more information Cannot determine realm for numeric host address  debug1: Unspecified GSS failure.  Minor code may provide more information Cannot determine realm for numeric host address  debug1: Unspecified GSS failure.  Minor code may provide more information   debug1: Unspecified GSS failure.  Minor code may provide more information Cannot determine realm for numeric host address  debug2: we did not send a packet, disable method debug1: Next authentication method: publickey debug1: Trying private key: /home/umairmustafa/.ssh/id_rsa debug1: Trying private key: /home/umairmustafa/.ssh/id_dsa debug1: Trying private key: /home/umairmustafa/.ssh/id_ecdsa debug2: we did not send a packet, disable method debug1: Next authentication method: password


Limit n approaches infinity of $\lim_{n \to \infty}(1+n)^{\frac 1n}$

I was wondering about $\lim_{n \to \infty}(1+n)^{\frac 1n}$. It is may not be as famous as Euler's limit but worth discussing. I searched the net but didn't get relevant proofs. I might miss though.  I thought one way, using LHopital, yeah kind of using a big result and don't know whether the proof is correct or not. I believe that there are plenty of easier proofs but I am not getting one.  Thinking $\lim_{x \to \infty}\log((1+x)^{\frac 1x})=\lim_{x \to \infty}\frac{\log(1+x)}{x}=\lim_{x \to \infty}\frac{1}{1+x}=0$ by raising it to the exponent we get the limit to be $1$.  Let me know your thoughts I think I still have to prove that the sequence is convergent first.


I would  like to understand  statement of Cauchy  integral theorem,which says that  Cauchy's integral theorem implies that the line integral of every holomorphic function along a loop vanishes: or     where  γ is a rectifiable path in a simply connected open subset U of the complex plane C whose start point is equal to its end point, and $f : U → C$ is a holomorphic function.   so  first  as  i know rectifiable means finite,also because we have such complex plane whose  start point is  the same as  end point,then does it means that it is similar to such situation when  we  have  $\int f(x)dx$ from $a$  to $b$  is equal to  $F(b)-F(a)$ and because  end  and start point is same ,then this  equals to zero? or  there is  two different path and they compensate each other?please help me to understand why this formula held?


Unable to access custom setting property obtained outside of Method()

In below class , I am unable to access the custom setting when it is queried outside of a method:  public class atestclass{      customsetting_Configs__c configs = customsetting_Configs__c.getValues('Custom_Setting_Name');     public static void aMethod(){        String hyperLink = configs.Field__C;    // Variable does not exist: configs.Field__C     } }   Works fine:  public class atestclass{       public static void aMethod(){         customsetting_Configs__c configs = customsetting_Configs__c.getValues('Custom_Setting_Name');         String hyperLink = configs.Field__C;    // Variable does not exist: configs.Field__C     } }


Difference between "will have to" & "would have to"

Joey: (picking up a leftover part) What's this?  Chandler: I would have to say that is an 'L'-shaped bracket.


How to speed up an st_intersects() query?

I have a "huge" spatial database: 72GB, 200 millions documents with geometries (points) I have a GIST index on the geometries  the database:  CREATE TABLE resources ( id bigint NOT NULL, accuracy varchar(3), owner varchar(100), title varchar(500), posted timestamp,    nbtags int, url text, description text, rawtags text, tags text, geom geometry NOT NULL, CONSTRAINT resources_pkey PRIMARY KEY (id) );  INDEX resources_index_rep ON resources USING GIST (geom);  CREATE RULE resources_rule AS ON INSERT TO resources WHERE EXISTS(SELECT 1 FROM resources             WHERE id =NEW.id) DO INSTEAD NOTHING;   Of course I want to query this database. Nevertheless, it's very very slow ... (I did analyzes and Vacuums)  for example with area of France:  EXPLAIN ANALYZE SELECT count(*)  FROM resources WHERE st_intersects(st_geomfromtext('POLYGON((-5.134723 41.364166,-5.134723 51.09111,9.562222 51.09111,9.562222 41.364166,-5.134723 41.364166))',4326), geom)  QUERY PLAN Aggregate  (cost=14411182.45..14411182.46 rows=1 width=0) (actual time=17368911.185..17368911.186 rows=1 loops=1)  ->  Bitmap Heap Scan on resources  (cost=890493.27..14391392.83 rows=7915848 width=0) (actual time=2627029.235..17357552.440 rows=21381758 loops=1)     Recheck Cond: ('0103000020E6100000010000000500000077137CD3F48914C05628D2FD9CAE444077137CD3F48914C0562B137EA98B4940F52EDE8FDB1F2340562B137EA98B4940F52EDE8FDB1F23405628D2FD9CAE444077137CD3F48914C05628D2FD9CAE4440'::geometry && geom)     Filter: _st_intersects('0103000020E6100000010000000500000077137CD3F48914C05628D2FD9CAE444077137CD3F48914C0562B137EA98B4940F52EDE8FDB1F2340562B137EA98B4940F52EDE8FDB1F23405628D2FD9CAE444077137CD3F48914C05628D2FD9CAE4440'::geometry, geom)     ->  Bitmap Index Scan on resources_index_rep  (cost=0.00..888514.31 rows=23747545 width=0) (actual time=2626090.609..2626090.609 rows=21381788 loops=1)           Index Cond: ('0103000020E6100000010000000500000077137CD3F48914C05628D2FD9CAE444077137CD3F48914C0562B137EA98B4940F52EDE8FDB1F2340562B137EA98B4940F52EDE8FDB1F23405628D2FD9CAE444077137CD3F48914C05628D2FD9CAE4440'::geometry && geom) Total runtime: 17368946.473 ms 7 row(s)   it took almost 5 hours.  and with Switzerland:  EXPLAIN ANALYZE SELECT count(*)  FROM resources WHERE st_intersects(st_geomfromtext('POLYGON((5.96611 45.829437,5.96611 47.806938,10.488913 47.806938,10.488913 45.829437,5.96611 45.829437))',4326), geom)  QUERY PLAN Aggregate  (cost=5623425.68..5623425.69 rows=1 width=0) (actual time=6798842.064..6798842.064 rows=1 loops=1) ->  Bitmap Heap Scan on resources  (cost=88982.29..5621452.65 rows=789212 width=0) (actual time=783383.496..6797250.482 rows=2539057 loops=1)     Recheck Cond: ('0103000020E61000000100000005000000AF5A99F04BDD1740D28BDAFD2AEA4640AF5A99F04BDD174028F38FBE49E74740B22D03CE52FA244028F38FBE49E74740B22D03CE52FA2440D28BDAFD2AEA4640AF5A99F04BDD1740D28BDAFD2AEA4640'::geometry && geom)     Filter: _st_intersects('0103000020E61000000100000005000000AF5A99F04BDD1740D28BDAFD2AEA4640AF5A99F04BDD174028F38FBE49E74740B22D03CE52FA244028F38FBE49E74740B22D03CE52FA2440D28BDAFD2AEA4640AF5A99F04BDD1740D28BDAFD2AEA4640'::geometry, geom)     ->  Bitmap Index Scan on resources_index_rep  (cost=0.00..88784.99 rows=2367636 width=0) (actual time=782664.847..782664.847 rows=2539063 loops=1)           Index Cond: ('0103000020E61000000100000005000000AF5A99F04BDD1740D28BDAFD2AEA4640AF5A99F04BDD174028F38FBE49E74740B22D03CE52FA244028F38FBE49E74740B22D03CE52FA2440D28BDAFD2AEA4640AF5A99F04BDD1740D28BDAFD2AEA4640'::geometry && geom) Total runtime: 6798852.955 ms 7 row(s)   it took almost 2 hours.  I'm looking for how to improve the performance?  About our server:  - CPU: 4 - RAM: 16 GB - OS: Ubuntu 12.04 LTS 64bit


How to create an annuity timeline on LaTeX

I was wondering, how can I create a timeline exactly like this one:    on LaTeX?  I am a Finance student, and write all of my notes using LaTeX. These timelines, are giving me a headache. Since we use a lot of different timelines because of annuities. I want to learn how to create one basic timeline, so that I can then change anything I want. But basically, I want something like this, with the arrows and everything.  Thank you so much guys!


Prove that if $T:V \rightarrow U$ is an invertible linear transformation then the inverse $T^{-1}: U \rightarrow V$ is also linear So, $T$ is linear and thus $T(v_1+v_2) = T(v_1)+T(v_2)$ for all $v_1,v_2 \in V$. Also, $T$ is invertible and so we can write $T^{-1}T(v)=v$ for all $v \in V$. I'm a bit confused trying to put this all together, help appreciated!!


Have a vague memory of an American film, possibly from the 90's about computers that became aware. Might have had some vague horror elements to it and the 'computers' were like shiny cubes.   I thought it was called Chronos but can't find anything under that.


Give a proof by cases that shows that $n(n ^2 − 1)(n + 2) $ is a multiple of  $4$, for all integers $n$  I have already done case 1 where n is even. I am doing case 2 where n is odd and I'm a bit confuse how to finish off the problem..Uploaded a picture of my work.. Is this work sufficient enough to prove that it is a multiple of 4? The 6k would not have any affect of the result in general?   I feel it is wrong because of the 6k. Right now my thoughts are if (statement) is a multiple of 4, then (statement) is a multiple of 2 as well. And work from there.


Settings menu in Ubuntu 17.10 is obliterated

I have no way of accessing any of my settings on my fresh install of Ubuntu 17.10.  I installed 15 minutes ago, added a few core packages, one of which was wine where dpkg failed and I had to restart it.  And it keeps telling me randomly that an install failed of : libsane1 (experimental).  After I installed those packages, no settings available.  The menus are gone, their icons are gone, they won't load even if they have an icon.    As soon as I got the first error message from dpkg, I did a   sudo apt-get remove libsane1   which went perfectly well and appeared to clear up the error.  Then back and did a   sudo apt-get install libsane1   which also went perfectly fine and no problems seemed to exist.  Only during the installation of wine-hq-staging on my fresh and clean ubuntu does the error appear.  Well it also appears on winehq-stable too but I did not use that this occasion.


I am smoothing the relationship between a binary variable y and a continuous variable x. For this I've looked into both GAM and LOESS, but I cannot find a good comparison of the pros and cons of the two methods. Could someone explain when to use one over the other?  I will not be using the smoothing for any predictive modeling, but only as a way of visualizing the relationship. I would of course prefer to find the most interesting aspects of the relationship between the two variables. I am not that interested in this question related to any particular dataset, but more in the general case of when to use one model over the other. That is why I haven't posted any plots or data.


I was wondering, because I couldn’t find that information anywhere, which version would be correct.  Let’s suppose somebody is telling me about :-) their :-) friend. I don’t know anything about the gender of that friend yet and I want to know how old... and here’s the question:        (...) how old they are.     (...) how old they is.       It’s about one specific friend that I don’t know the gender of.  Of course I could ask: „How old is your friend?” Or „How old is he or she?” but I’d like to use Singular they if possible.  So, should I ask: "How old is they?" or "How old are they?"? Or maybe Singular they doesn’t work here?


Analytical solution for adding up this sequence of numbers

Is there an analytical solution for adding up this sequence of numbers?  $$ n + \frac{n}{2} + \frac{n}{4} + \frac{n}{8} + \ldots + 1 $$  For example, let $n=32$,   $$ 32 + \frac{32}{2} + \frac{32}{4} + \frac{32}{8}+ \ldots + 1 = 32 + 16 + 8 + 4 + \ldots + 1 $$  I believe, we can express the formula like this:  $$f(n) = \sum_{i=1}^{\log(n)} \frac{n}{2^i}$$  However, is there an analytical solution to this problem?


In Java, how do I parse XML as a String instead of a file?

I have the following code:   DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(xmlFile);   How can I get it to parse XML contained within a String instead of a file?


Find a limit related to a convergent series.

If $\sum a_n$ is a convergent series and $S=\lim{s_n}$ where $s_n$ is the $n$th partial sum, how would I prove that $\lim_{n\to \infty} \frac{s_1+...+s_n}{n} = S$?   I'm not sure where to start, I've been having trouble understanding partial sums. Any tips on where to begin?


Story about human space explorers who run into alien telepath space crew

I read a short story in an anthology around 1998 (the book could have been older than that) which went like this - A human space exploration scientific crew is exploring an alient planet (peaceful planet, as I recall) when they run into an alien spaceship (from a different planet which also happened to be there) - the aliens were telepaths.   The alien commander and first officer discuss the earthlings after a meeting and realize that the human crew are the descendants of a species (Banthu/Klanthu/Zantha, something like that) which had tried to violently take over the galaxy some 20/30/50,000 years ago and which had been beaten back by the combined might of the rest of the galaxy. They had supposedly been eliminated but they somehow managed to survive and are back in space only a few thousand years after they were completely beaten (which is something the aliens are amazed by).   The alien commander kills the human explorers via telepathy but realizes that there is no information available to locate their home planet and speculate that they will be meeting again soon given the past history of the humans.  I vaguely think there was also a fantasy short by L Sprague de Camp in the same anthology, but can't be 100% sure. Any thoughts/ideas? Thanks!


Battery chargers that can recharge disposable batteries. How do they work and are they safe?

A few years ago a product called  appeared, which claimed that it could recharge disposable batteries. To a layman like me that sounded like a great idea, but does such a product really work, and is it actually safe to use?  The labels on the batteries promise nothing but certain death if you try to recharge them, and a charger for disposable batteries seemed like something that might be potentially hazardous.


What is the benefit of the "hover to reveal additional buttons" interface found in Gmail?

When you compose a new message in Gmail on a computer, the bottom of the compose window looks like this:    When you put your mouse over the + button, it looks like this (with the mouse being on the icon with the tooltip)    I'm not understanding the rationale for hiding these five additional buttons until the user hovers over the + button. There is enough real estate that this would not be necessary and it seems to me that there are downsides, notably the lack of immediate visibility making these features less discoverable (not to mention that it's not obvious what the + button is for). Indeed, I would think that they ought to always be visible. I haven't seen this sort of interface before and I'd like to think that Google had a good reason to do this. Could someone please let me know what it is?


Two humans land on a planet; one learns to communicate with aliens

I read a book sometime between 1999 and 2002, possibly young adult. It starts out with a spaceship containing two astronauts landing on a foreign planet. One, a man, is rendered unconscious; the other, a woman, is the main (human) character. The planet has native life, including an intelligent species. Chapters of the book alternate being narrated by the female astronaut and one of the aliens. The point of the plot is depicting the woman and the alien as they gradually learn to communicate. I believe it ends with the woman and her injured partner leaving the planet after she has successfully learned to communicate with the alien.  At one point the alien is confused by the woman's spacesuit, thinking it is her real skin, and is surprised when she starts "shedding" it.  The alien also consistently refers to fingers as "digits", something that really confused me when I was a kid.


How to obtain covariance matrix eigenvalues from singular values?

I would like to implement closed form of PPCA (). In this paper they calculate $W$ in formula (15):  $W=U_q(K_q-\sigma^2I)^{1/2}R$  where $K_q$ is a matrix from eigenvalues $\lambda_i$ of covariance matrix as defined in formula (5).   On one hand I , that it is possible to calculate eigenvalues with  $\lambda_i = \frac{s_i^2}{n-1}$  Is it true, that principal values depend on number of samples $n$?  On other hand I found python implementation of closed PPCA on github, , where it is written      mu = np.mean(self.y, 1)[:, np.newaxis]     [u, s, v] = np.linalg.svd(self.y - mu)     ...     else:         ss = s[:self.q]     ss = np.sqrt(np.maximum(0, ss**2 - self.prior_sigma))     w = u[:, :self.q].dot(np.diag(ss))   where author is apparently calculating with  $\lambda_i = s_i^2$  which is completely different.  UPDATE  Here $s_i$ is diagonal element of singular values matrix.   UPDATE 2  I have tried numeric example  X = np.float64(np.array([     [-1, -1],     [-2, -1],     [-3, -2],     [1, 1],     [2, 1],     [3, 2]]))  n_samples = np.shape(X)[0]  X -= np.mean(X, axis=0)  pca = PCA(n_components=2) pca.fit(X)  cov_matrix = np.dot(X.T, X) / n_samples  singularvalues = pca.singular_values_  for i in range(len(pca.components_)):     eigenvector = pca.components_[i]     eigenvalue = np.dot(eigenvector.T, np.dot(cov_matrix, eigenvector))     singularvalue = singularvalues[i]     eigenvalue2 = singularvalue**2 / n_samples     print("%f\t%f;\t%f" % (eigenvalue, singularvalue, eigenvalue2))   output  6.616286    6.300612;   6.616286 0.050381    0.549804;   0.050381   and found that answer depends on covariance matrix normalization.  UPDATE 3  In the other hand it is written in Python's :     The rows of v are the eigenvectors of a.H a. The columns of u are the   eigenvectors of a a.H. For row i in v and column i in u, the   corresponding eigenvalue is s[i]**2.   UPDATE 4  Ah, sure, a.H a is "scatter matrix", i.e. covariance matrix w/o normalization.


I have html code with radio buttons and some common button. After click common button I copy this code with .clone and insert after with .after. In first block I have radio buttons with name like 'name', in second I change this name like '1name', in third -'2name' and etc. Moreover I have js code      $('input[type=radio]').change(function(){             var index= $(this).attr('rbgindex');             var name = $(this).attr('name');             $('.hid-'+name).remove();             $(this).parent().after('<input class=hid-'+name+' type=hidden name='+name+index+' value='+index+' checked>');     });   It should create hidden filed after change radio button. But I have problem with it. If I change radio button in firsy work, it work, but in another it doesn't work. What's wrong?


Why is it possible to submit an answer to a closed question by tweaking the HTML of the page?

One time, I was writing an answer to a question, when the question was closed. I had spent a little time on the question, so I didn't want to lose it. The post button was disabled, so I inspected it and saw that there was a single attribute disabling it: disabled = "disabled"  I undid it, and was able to post my answer, even though the question was closed. There was no JS to keep me from posting it. Is this intentional, or just a mistake that the developers never thought about?


Why $\prod_{i\in I} \Bbb Z$ is not a projective $\Bbb Z$-module?

Let $\Bbb Z$ be the ring of integers and $I$ a non-countable index set. Why $$\prod_{i\in I} \Bbb Z$$ is not a projective $\Bbb Z$-module?


Import data with Comma as decimal seperator and do calculations

I would like to read data from a csv and then do some calculations. The problem here is the comma as a decimal separator. With a point as decimal seperator in my csv data everything woks but with a comma it does not. Are there any solutions available to solve my problem?   \documentclass{article} \usepackage{pgfplotstable} \pgfplotsset{compat=newest}  \pagestyle{empty} \begin{document}  \begin{tikzpicture} \begin{axis}[xlabel=$x$,ylabel=$y$] \addplot [             color=red,             only marks,             mark=*,             mark size=1.5pt,           ]          table          [ col sep=semicolon,            /pgf/number format/read comma as period,             x=x,             y expr=\thisrow{y}*2            ] {test.csv};  \end{axis} \end{tikzpicture}  \end{document}   The Data:  x;y 1;1 2;1 3;1 4;8,5 5;2 6;2


I've been having a debate (mostly with myself) over the best approach to deal with invalid input in text fields -- validation versus prevention.    Taking a  numeric text field as an example, is it better to prevent the entry of non-numeric characters (allowing for special cases like sign, decimal pt., etc.) or allow the entry of whatever and then indicate an error message (typically when focus is left) if the result is invalid?    The first approach is "don't allow the user to do something you know is wrong" but has the disadvantage that it may not be at all obvious what is going on if a keyboard key is typed and nothing happens.  It also breaks the expectation that, if you type something in a text field, you expect to see what you typed.    In the past, I've generally leaned towards the prevention approach but in general but feel perhaps, at the field input-level, the validation approach provides a better user experience.  Is anyone aware of a best practice here?


Using foreach iterator value inside EventHandler

I have something that looks similar to the following:  public class MyClass {     private List<MyOjectMapping> mappings;      public void Start()     {         foreach (var mapping in mappings)         {             mapping.ObjectA.PropertyA.PropertyChanged += (s, e) =>             {                 // do something with mapping.ObjectB             };         }     }      public void Stop()     {         // unhook events     } }  public class MyObject : INotifyPropertyChanged {     public object PropertyA;     public object PropertyB; }  public class MyOjectMapping {     public object SomeSortOfKey;     public MyObject ObjectA;     public MyObject ObjectB; }   As you can see, I'm trying to perform some action on the foreach iterator inside the lambda event handler. This works, but doing it this way, I can't figure out how to unhook the events in the Stop() method.  How should I go about hooking up the PropertyChanged event so that I can unhook it later and still access the foreach iterator?  Thanks


How can I see my favourite question in the Android App? I can favourite questions but don't know how to see them.


I want to fetch the text between ** and **.  This is what I am trying with:  /\**(.*)\**/ig   This is the sample string  ** The ** *quick* ~~brown~~ fox ** jumped **   please ignore the space after ** and before **  As a result, I am getting the whole string fetched


Bootstrapping Juju 1.13 to private OpenStack

I've been trying for ages now to get Juju to bootstrap with my private OpenStack installation. Starting with 1.11 I've been stuck with this error during bootstrap:  error: cannot start bootstrap instance: no "precise" images in RegionOne with arches [amd64 i386]   In 1.11 I was able to use 'juju image-metadata' to create the index.json and imagemetadata.json files for upload to Swift (though I still never got past the error), but this command no longer exists in 1.13, and I can't find any mention of a replacement.  Is there a way to bootstrap a private OpenStack cloud with Juju 1.13? And if so, is there any documentation to guide me through from scratch? I'm eager to learn how to develop Juju services, but I can't even get it bootstrapped!  ** Edit: The primary issue is that the 'juju image-metadata' is missing, so I'm not able to follow the instructions in the linked question. Is there a replacement to 'juju image-metadata'?  * I have tried both commands, both report as missing. Thanks for your help so far!


I'm trying this in 16.04 but it is not working. Taken from: .   Edit: Apparently this works if you copy and past it to a terminal but not on a script file. How do I get it to work the same way on a .sh file?  declare -a arr=("element1" "element2" "element3")  for i in "${arr[@]}" do    echo "$i" done   I get  old.sh: 2: old.sh: Syntax error: "(" unexpected   If I take out the brackets, I get   old.sh: 2: old.sh: declare: not found old.sh: 5: old.sh: Bad substitution


Should sentences like "I wonder..." end with a question mark?

This may be related to a general grammar rule, but which of these is correct?     I wonder if Steve Jobs will be giving the keynote speech at WWDC this year?   or     I wonder if Steve Jobs will be giving the keynote speech at WWDC this year.   My hunch tells me the question mark is incorrect, but I find myself instinctively wanting to add it. Is there a rule about this type of situation?


When deleting files from the Desktop folder on Win10, why do I need to refresh the Desktop?

Running Win10 (V 1511 b 10586.589)...  When I delete files from File Explorer > Desktop, the files remain on my desktop. If I try to open them from the actual Desktop (and not the folder in Explorer), an error message pops up saying the file has been removed. I need to manually right click on the root window and do a "Refresh". It seems very odd to me that major state changes on the primary UI don't trigger a UI refresh.    This equal parts gripe and genuine curiosity. I'd like to know if there is a programmatic reason behind this. Is it because Win10 is multi-platform and is associated with some weird table<>laptop UX conflict? Is it too computationally expensive to do a refresh? Might it trigger a long-latency IO (disk or network), so to hide the latency they associate it with a user-initiated action? Or is it a gross oversight?  This is not a duplicate of the Win7 question () because I want to know WHY this is the case. I already know how to fix it. I'd like to know if there is an underlying strategy for this odd UI behavior, specifically from windows super-users.


Principal Components Analysis Terminology

I've been studying PCA, and some of the terminology isn't very clear. I do not understand what they mean when they refer to a "principal component". One definition I have seen calls it the new coordinates after the transformation the original data. Another calls these new coordinates the principal component scores. Clarification would be greatly appreciated.


is there a way to reference the subsection part only? Example:  \documentclass{article} \begin{document}  \section{This is my section} For further information see subsection \ref{subsecthree} within this section. \subsection{One} \subsection{Two} \subsection{Three}\label{subsecthree}  \end{document}   Usually gives (without the stars):  1 This is my section For further information see subsection **1.3** within this section.   But I want:  1 This is my section For further information see subsection **3** within this section.   Is that possible?  [Edit] To make it more clear: I am looking for a command that works like \ref, but prints (the arabic number of) the value of the subsection counter at the position of the \label.  ======================= == Solution in LaTeX ==  There is another solution below. This is a different solution I came up with  (I cannot post an answer to my own question, so I put it here):  \documentclass{article}  \newcommand{\labelsubseccounter}[1]{     \renewcommand\thesubsection{\arabic{subsection}}     \addtocounter{subsection}{-1}     \refstepcounter{subsection}     \label{#1}     \renewcommand\thesubsection{\thesection.\arabic{subsection}} }  \begin{document}  \section{This is my section} For further information see subsection \ref{subsecthree} within this section,  which is called \ref{onepointthree}, not \ref{onepointfour}. \subsection{One} \subsection{Two} \subsection{Three}\label{onepointthree}\labelsubseccounter{subsecthree} \subsection{Four}\label{onepointfour}  \end{document}   (I would like to insert the compiled code, but don't know how, sorry)


Regular expression \p{f} and \p{Zs} in javascript

I'm the new to regular expressions in JavaScript. I see the expressions in C# have the label,such as"\p{f},\p{Zs},p{Lu},p{Lt},p{Lo}". But I add this in JavaScript , it doesn't work. So, how can I change these to JavaScript format that make it can work.


I have read that watchdog timer pushes microprocessor/controller into reset state whenever it experiences any software anomaly like executing in infinite loop. and after some time a very senior prof told us that after reset the processor resumes operation from the next instruction to the erroneous one.  when watchdog timer resets the processor, from where does the processor start its next execution?  I just wanted to know what is correct or if some other concept is employed?


Why I can't get the name through the pointer to the element before the last one?

I want to get all names and print them.  How to fill the array of structure and then print data from each element in the array?  I can't even get the name before the last one element. . The main problem in a char* because with string it works. But I need to do it without strings. It gives me this error:  Exception thrown at 0x0FADF6BC (ucrtbased.dll) in Vuz.exe: 0xC0000005: Access violation reading location 0x00000001  #include <iostream> #include <stdio.h> #include <vector> #include <algorithm> #define SIZE 2 using namespace std;  struct Student {     const char* name;     const char* surname;     const char* major;     int group;      Student(){}      Student(const char* name, const char* surname, const char* major, int grp)     {         this->name = name;         this->surname = surname;         this->major = major;         this->group = grp;     }  };   int main() {     Student* st = new Student[SIZE];      for (int i = 0; i < SIZE; i++)     {         char name[30];         char surname[30];         char major[10];         int group;          cout << "Enter name, surname, major and group of new student" << endl;         cin >> name >> surname >> major >> group;          st = new Student(name, surname, major, group);         *st++;     }     *st--;     *st--;//Here I have a problem     cout << st->name << endl;      return 0; }   I want to fill this array correctly(using char* ) and print all these names.


Should I use an equality sign or "iff" for a definition?

In many mathematical textbooks the definitions are given in the following form (considering even numbers as an example): "A natural number n is called even iff it is a multiple of 2". Now as we know a definition should serve only as an abbrevation. That is I can use the following form for defining even numbers. "Even number = a natural number that is a multiple of 2". Is there any difference between the above definitions? I was thinking that the first makes the definition more strict. For example, suppose that I state: "$1.5$ is an even number". According to the first definition this statement is meaningless because the term "even" is defined for natural numbers. According to the second definition the statement should be false because $1.5$ isn't a natural number. Which of the above definitions is more appropriate and why? Edit I have read the question with the proposed answer before I asked this question. But there is a difference because I am asking what notation should I use and if there is a difference between equality sign and "iff" whereas the other question is about the difference between "if" and "iff".


I'm creating a stopwatch with setInterval like this:  <!DOCTYPE html>               <meta charset="utf-8">         <title>Stopwatch</title>         <link href="https://fonts.googleapis.com/css?family=Saira" rel="stylesheet">         <link href="stopwatch.css" rel="stylesheet">         <link href="https://fonts.googleapis.com/css?family=Droid+Sans" rel="stylesheet">

Stopwatch

0
             <button id="start">Start/Stop</button>             <button id="reset">Reset</button>             <button id="record">Record Time</button>
              and the JavaScript file:  var timer = document.getElementById("timer"); var sec = 0; var on = false; var interval; //execution document.getElementById("start").addEventListener("click", startStop); //function function startStop(){     if(on == false){         counter();         on = true;     }else if(on == true){         clearInterval(interval);         on = false;     } }  function counter(){     interval = setInterval(time, 1000); }  function time(){     sec += 0.01;     timer.innerHTML = sec; }   I set the interval at 1000 to test it. It worked well at the first 5 seconds, but at the 6th second, the number shown was 0.060000000000000005, and the 9th, 10th, 11th didn't work as well. Can anybody help me fix this problem please?


Is Stack Exchange/Stack Overflow staff really interested in users' feedback?

After some years of enthusiasm about Stack Overflow and other Stack Exchange sites, admiring the politeness of the communities and the effectiveness of the whole system, I finally stumbled upon a serious problem, and decided to make a complaint to the staff. In this page , I've read about what to do in that case, of course after having made the other recommended actions. I wrote a message using the "Contact" link "at the bottom of any page", as stated. Two months have passed, and still nothing is happened, not even a signal that someone did read my complaint. I then searched for some other way, and found this page:  where there is a list of people that should "help you out, really". In their profile page you can find their email addresses. I wrote an email to three of them, leaving some day between each one. Again, no replies, no signals that someone has even received my messages. Now I wonder: are these people really interested in user's feedback, or at least interested in ensuring that no abuses or other serious problems grow in their communities? This is question 1. Question 2: Are those email addresses fake or what? Are they supplied just to give the impression that someone cares about users? Question 3: What can I do now? Should I sit in peace and leave? Or is there still something I can try, once again? --- update --- It has been suggested that this question:  could be the right answer. I think no, because it is 3 years old and it does not suggest what to do other than wait for a week. I've read that there are, these days, new efforts in improving exactly these kinds of problems. I am referring, for example, at the tag "status-review". Moreover, I want to understand better what the Community Team does (): I wrote an email to some of them, but nobody replied. Wouldn't it better, at least, to inform the user with something like "we received your email but we have no time to examine it: please be patient"? Now I have the doubt that the mail system does not work, but it seems more probable that the CM really does not reply.


How can you tell what version of minecraft you have?

How can you tell what version of Minecraft you have? I have tried looking in the app store and it doesn't show me the version I have.


Strange padding around reputation on Meta profile page

The way reputation is displayed on a user's profile page on meta sites is a bit off. There's gray padding around it:  which is not visible on the main site:  The 'top x%' label being so close to it makes it even worse. This affects both  and .


How we see laser light if it travels in a straight path?

Light travels in straight path, and our eyes detects an object's reflected light then we see the object. So if laser light is going in a straight path, how come we can see laser light?


Choosing an advanced group theory text: concerns

In  question, An Introduction to the Theory of Groups by Rotman is recommended twice as a good second-course group theory text.  However, after reading the reviews , and seeing  pdf of what seems to be corrections to Rotman, I am pretty concerned about the apparently many errors in the text.  While some errors and their corrections may be pretty self-evident, I would hate to constantly be worrying about developing some misconception as a result of some fact that isn't presented quite as it should be.     To those who have read An Introduction to the Theory of Groups by Rotman: do you feel the errors are a serious concern/disruption to the flow of the text, or is the book still pretty navigable?   Also recommended in the question linked to above was  by Robinson.  I really like the look of this text, based on the table of contents and the group-theoretic concepts that really interest me.  The Robinson text is said (in the linked-to question) to 'move pretty quickly into deeper waters.'  My background consists of basic group theory, ring theory, field theory, a little Galois theory, linear algebra, topology, real analysis, and graph theory (I have seen a decent amount of material and have been self-studying for a few years now).       Do you think that I can reasonably wade into these deeper waters without going in over my head and drowning?  I realize this is a little subjective since no one knows my exact abilities, but I love group theory and am definitely willing to put some real effort into it.   Thanks in advance for the advice.


I have an issue where I'm trying to make it a "Trusted host patterns" on settings.php. It gets an issue of "The provided host name is not valid for this server." I have tried many times to get it to work, the issue work with: $settings['trusted_host_patterns'] = array(   '^', );  But will not get the following to work $settings['trusted_host_patterns'] = array(   '^sandbox\.dev$', );  Thanks


Why does Ubuntu Download recommend 64-bit install?

Why would Ubuntu as a generalized statement recommend its 64 bit “flavour”?   As far as I understand a 64-bit OS can only be installed on a 64-bit hardware (CPU), i.e. 32-bit and 64-bit OS can be installed on a 64-bit hardware, but only a 32-bit OS can be installed on a 32-bit hardware (regardless of the amount of RAM available).  You can see this on the :  .   EDIT I understand , and I see the pros and cons. For users with a 32-bit hardware this is not a question of choice. Recommending a 64-bit OS without taking into account the hardware is like recommending petrol over diesel and neglecting the engine. The download site does not check for 64 bit processor hardware, and if detected recommend a 64-bit OS, but recommends a 64-bit OS to all users (with more than 2 GB RAM).   It has been stated that ”manufacturers don’t really make 32-bit systems any more” (Dalton), and that “almost all chips in recent history are 64 bit” (oldfred). This is true at least for . So this recommendation simply reflects a trend in industrial production?


70s YA novel about two boys travelling millions of years into the past, meeting a "cynogasaurus" and rival animal-themed caveman tribes

I read this in English in the late 70s in primary school. What I remember:  Two boys are somehow caught up in a time travel scenario. I think their father may have been the inventor of the time machine. Their initial journey takes them back about 200 million years. They meet an animal they identify as a cynogasaurus. At least, that's what my memory told me. Google tells me my memory may be playing tricks and they met a  instead. It was definitely cynogsomething. They somehow jump forward to caveman times with the cynogasaurus/cynognathus in tow. They befriend a similarly-aged kid who's a member of a particular tribe, possibly the leopard tribe. The leopard tribe are enemies of the zebra tribe. It's possible I've got both animals wrong. Each tribe has a sacred animal. Disputes between the tribes are settled by their sacred animals fighting. Somehow the kids have caused the death of "their" tribe's sacred animal so they offer the cynogawhatsit, which the cave-people call Nog, in its place. Nog wins the fight and stays on as the sacred animal when the kids leave.  Edit: I thought it may have been Lester Del Rey's "Tunnel Through Time", the subject of a few queries here over the years. The cover looks familiar and some details match. However two comments have verified that it doesn't feature the cynog* creature, sacred animals or the fight, which are what I recall about the book.


Is using htmlspecialchars() and using placeholders in SQL enough to stop attacks on my website?

I have finally finished my login and register form WITH e-mail verification and I am SO happy! I am just not sure if my form is secure enough. I've used htmlspecialcharacters() on all user inputs and used placeholders in SQL queries. Is this enough to stop attacks on my form? Please help, as all answers are appreciated. Thanks! This is the code for my register form:   <?php include_once 'compat.php'; $user = 0; $pass = 0; $mail = 0; if($_SERVER['REQUEST_METHOD'] == 'POST' && !empty($_POST['mail']) && !empty($_POST['user']) && !empty($_POST['pass'])) {      function an($subject) {         if(ctype_alnum($subject)) {             return true;         }     }      if(an($_POST['user']) && strlen($_POST['user']) <= 20) {         $user = htmlspecialchars($_POST['user']);     }     else {         echo 'username is invalid (a-z A-Z 0-9 and less than 20 characters, please)
';     }     if(filter_var($_POST['mail'], FILTER_VALIDATE_EMAIL) && strlen($_POST['mail']) <= 255) {         $mail = htmlspecialchars($_POST['mail')];     }     else {         echo 'email is invalid
';     }     if(strlen($_POST['pass']) <= 255) {         $pass = htmlspecialchars($_POST['pass']);     }     else {         echo 'password must be less than 255 characters
';     }     if($pass && $user && $mail) {         $hash = md5(rand(0, 1000));         require_once('db.php');         $sth = $db->prepare("                                 INSERT INTO user_info (username, password, email, hash)                                 VALUES (:username, :password, :mail, :hash)                 ");         $sth->bindValue(":username", $user, PDO::PARAM_STR);         $sth->bindValue(":password", password_hash($pass, PASSWORD_DEFAULT), PDO::PARAM_STR);         $sth->bindValue(":mail", $mail, PDO::PARAM_STR);         $sth->bindValue(":hash", $hash, PDO::PARAM_STR);         $success = $sth->execute();         echo 'You have been successfully signed up :)! To activate your account, click the link in your e-mail account (check your spam box if you don\'t get the e-mail!)
                 The last step to activating your account is clicking this link!:
                 http://localhost/verify.php?mail=' . $mail . '&hash=' . $hash . '
                 ';     } } ?>


How can I select a bunch of text and comment it all out?  Currently I go to the first line, go to insert mode then type # left-arrowdown-arrow and then I repeat that sequence, perhaps saving a few keystrokes by using the . repeat feature to do each line.  Is there anyway I could (for instance) select either multiple lines in visual mode or by using a range of lines and an ex ('colon') command and for that range comment out all the lines with a # to make them a "block comment".  The ability to quickly 'de-comment' (remove the #'s) for a block comment would also be nice.


Ordinary differential equation $y'(t)=\sin(f(t,y))$

One whose solution never makes me happy is the following: $$y'(t)=\sin(y+t)\text{.}$$ I would start by substituting $z(t)=y(t)+t$ to get an ODE in $z(t)$, but then I'm not sure about how to substitute back my solution to check if it's correct or not$\dots$


Prove by induction $4^n > n^2$ for $n \geq 1$

I am in a critical problem with the following question. Please help me.  Prove by induction: $$4^n > n^2 \text{ for }n >= 1$$  Base case: n = 1 $$4^1 > 1^2$$ 4 > 1 which is true and for some n = k > 1 we have $$4^k > k^2$$  Next, Induction step: Now setting n = k+1 we get $$4^{k+1} > (k+1)^2$$ $$4(4^k) > k^2 + 2k + 1$$ Now how will I proceed?


I changed my iTunes account location to German (with an Austrian credit card) in order to download a certain app that wasn't available in Danish (my primary language). I was now able to get the app from the German App Store. Afterward, I set the location back to Denmark and entered the Danish credit card that I was using before.   Problem: When I now visit the App Store (on my iPhone), it is still in German. How do I switch the iPhone App Store back to the language that is set in iTunes? iTunes has got it right, but why doesn't my iPhone see the same status?  I expected that it would be enough to just plug it into the PC and let it sync itself, but that wasn't the case. I've just synced the phone with the PC and that went without problems, but the iPhone App Store is still in German while the PC iTunes has the Danish account ("Country/Region: DNK").


Can I pull some files from a specific branch, modify them and push them to another branch in the same github repository?

I tried it with some random text files, that I created on github, pulled them on my computer, modified them, then I created a separate branch on github, called 'another'. When I tried pushing the modified files from my computer to github using git I got the message: error: src refspec another does not match any<br> error: failed to push some refs to 'https://github.com/username/repo-name.git'  What I typed before: git push origin another


I have a string of dates in php (dd/mm/yyyy) that I want to convert to yyyy-mm-dd format.  I have tried :  UPDATE `table` SET `DATE_VAR` = convert(datetime,'19/03/2015', 121) WHERE `ID`=160   Can you help me?


An  is a prime number such that when its decimal digits are reversed, one obtains a different prime number. Are there infinitely many ermips?  It is apparently open whether there are infinitely many   (a somewhat related but disjoint notion).


Differences between in and on the market

"The monitors in the market" or "The monitors on the market". What is the right way? The software I use says "in" is wrong and it suggests "on".   To give context: I am talking about the computer monitors that I could find in the market.  Can someone explain the two options here, please?


Why is the salt not more than 8 ~ 16 characters long?   Also, why in most cases is it in the front or end of the password, and not in different positions?  Is this to make it harder for the breaker? Or is it useless?


Let $G = A_5.$ Prove that $\langle (1,2)(3,4), (1,2,3,4,5)\rangle = G$ . State clearly any properties of $A_5$ you use.   So I know $A_5 = \{\sigma | \sigma \in S_5$ and $\sigma$ even permutation$\}$.  I'm trying to expand $\langle (1,2)(3,4), (1,2,3,4,5)\rangle$ to show that it equals $A_5$ but I'm not getting the answer.  $(1,2)(3,4)(1,2)(3,4) = (1)$  $(1,2)(3,4)(1,2,3,4,5) = (1,3,5)$ But this is odd, so it wouldn't be in $A_5$.  How do I approach the question correctly?


Calculating length of line using British National Grid projection?

I need to calculate the length of a line in (KM) in QGIS using the British National Grid as the Projection.  Can somebody explain to me how to do this?


I have 2 classes   public class A {     public A(string N)     {         Name = N;     }     public string Name { get; set; }      public void GetName()     {         Console.Write(Name);     } }  public class B : A {     public B(string N) : base(N)     {     }      public new void GetName()     {         Console.Write(new string(Name.Reverse().ToArray()));     } }   I create a new object B which I want to call GetName from A and GetName from B  B foo = new B("foo"); foo.GetName(); //  output "oof"   Expected Output "foooof"  I already tried public new void GetName() : base but that does not compile


Let $y_n$ be a sequence such that  $\lim_{n\to \infty} y_n= y$ then prove that     $ \lim \dfrac{y_1+y_2+...+y_n}{n}= y$   My try:  As  $\lim_{n\to \infty} y_n= y$ then given $\epsilon>0$ there exists $N$ such that $\forall n\ge N ;||y_n-y||<\epsilon $.  Now $||\dfrac{y_1+y_2+...+y_n}{n}-y||\le n^{-1}\{||y_1-y||+||y_2-y||+...+||y_n-y||\}$  How to make this limit tend to zero?


I am using Ubuntu 19.04 version. And when I want to install any software, I always use sudo apt-get update.  But it is failing every time. I am new in this field. Because of that error I can not install GNU Emacs.  It is showing:  $ sudo apt-get update Hit:1 http://ppa.launchpad.net/kelleyk/emacs/ubuntu disco InRelease Hit:2 http://archive.ubuntu.com/ubuntu bionic InRelease Get:3 http://security.ubuntu.com/ubuntu bionic-security InRelease [88.7 kB] Get:4 http://archive.ubuntu.com/ubuntu bionic-updates InRelease [88.7 kB] Reading package lists... Done                                         E: Release file for http://security.ubuntu.com/ubuntu/dists/bionic-security/InRelease is not valid yet (invalid for another 40min 7s). Updates for this repository will not be applied.


I can create a symlink:  > mklink bravo.png alfa.png symbolic link created for bravo.png <<===>> alfa.png         However this is on a virtual machine. For some reason if I create one on my actual computer I am getting this:        Notice:   No thumbnail image If I double click the symlink in the virtual machine, it opens alfa.png in Photo Viewer, as expected. However if I double click the symlink on my computer it presents the “Open with” window. The symlink says “PNG image” in the virtual machine, it says “SYMLINK File” on my computer.   I think some registry setting is the culprit here, but I am not sure which one.


Is there a way tp produce a similar plot in latex


Set $A\subset \mathbb{R}$ so that $\lambda(A\cap [a,b])>0$ and $\lambda([a,b]\setminus A)>0$.

Build a set $A\subset \mathbb{R}$ so that for all interval $[a,b]\subset \mathbb{R}$  meets the following two properties:   $\lambda(A\cap [a,b])>0$. $\lambda([a,b]\setminus A)>0$$   Where $\lambda$ is Lebesgue Measure.  The true is thatI do not have any idea how to build this set A. I hope can help me. Thanks!


Why is tension in string different for pulley having mass?

Why is the tension in the string different in the diagram below? Why can't we use the same tension for both the strings as we usually do in Atwood system?


Setting title for a vf page with rendered as PDF to view title when it loads

I am trying to change title of a visualforce page which is rendered as PDF. But adding title attribute to apex:page tag,   or even adding title in head tag,  <apex:page controller="NMAT_PaymentReciept" title="Payment Acknowledgment Receipt for NMIMS Application" showHeader="false" sidebar="false" renderAs="pdf">     As of now its showing pages Name  Please help...this is frustrating.  Thanks for time!


"It is one of the few terms that cast/casts a positive light on this subject."

What should the verb "cast" agree with in the example below?  Should the verb "cast" be conjugated as "cast", agreeing with "terms" (terms that cast a positive light)     It is one of the few terms that cast a positive light on the subject.   or should "cast" agree with "one" .. (one (of the terms) that casts a positive light)     It is one of the few terms that casts a positive light on the subject.   Should it be the first, the second, or is either correct?


Disable rsyslog remote server 's console messages

My console is been flooded with rsyslog messages. These are messages that come from a remote server:     Message from syslogd@MSAN-RSPAE_O1A0F at Mar  3 11:07:13 ...  rOT1[291]: 17/03/03 11:07:13 minor alarm occurred for service-id 703 mac-idx 17 (service affecting) : VPLS Duplicate MAC address, mac:00-A0-12-6F-4B-80,dup-port:ntio-1:sfp:7,dup-vlan:703,port:nta:xfp:1,vlan:703,cvlan:0,,   I'am trying to stop these messages to be printed to the console. Already tried changing the config file /etc/rsyslog.conf  #kern.*                                                 /dev/console   to  .*                                                      /dev/null   and restarting the rsyslogd after  sudo service rsyslog restart   Already tried the:  sudo dmesg -n0   And until now, the messages keep appearing in the console of all users.  How to disable them once and for all?


I want to have two matrixes of $ A $ and $B$ of a certain size, multiply them together $C = AB$, do some operations on $C$ to make $C_2$ and then decompose the matrix into to matrices of the same size as $A$ and $B$ so that $A_2B_2 = C_2$.  Which decomposition function can I use to achieve this?  EDIT: This is not a duplicate because the thread linked in the comments using LU decomposition says nothing about L and U being the same dimensions as the original matrix


Is there any equivalent to TortoiseSVN but for Ubuntu / Git? I'd like to integrate Git commands to Nautilus.


As I use the Docky Skype indicator, and the green Skype icon doesn't look good next to all the grey ones -- it would be nice to remove the icon from the system tray.   Is this possible? How can I do it in Ubuntu 12.04 -- or other earlier versions?


Showing that $\|f\|_{p}=\sup\left\{ \left|\int_{X}fg\right\|:g\in L^q(X),\|g\|_{q}\leq 1\right\}$

Let $f\in L^p(X)$ and $1/p+1/q=1$. Show that $\|f\|_{p}=\sup\left\{ \left|\int_{X}fg\right\|:g\in L^q(X),\|g\|_{q}\leq 1\right\}$ Hi. I'm stuck proving that $\|f\|_{p}$ is the lowest upper bound. I have only is upper bound because $\|fg\|_{1}\leq \|f\|_{p}\|g\|_{q}\leq \|f\|_{p}$ by Holder's Theorem, and $\left\|\int_{X} fg\right\|\leq \|fg\|_{1}\leq \|f\|_{p}$ but, why $\|f\|_{p}$ is the lowest upper bound?$}


What is exact value of $\sum_{n=1}^{\infty} \frac{1}{n^n}$ .

I would like to ask if anyone would help me with solving the following infinite series. \begin{equation}     \sum_{n=1}^{\infty} \frac{1}{n^n} = \,? \end{equation} Thank you in advance.


Answers deleted when the question is deleted

The other day I was answering to a question by a very long text, it take me a long time to do it because I have done some research, but anyway it was on an interesting subject, so it was worth it.   Some minutes after I had post my answer, I've seen that the question has been deleted by the user and my long answer too. I was a bit angry because I feel that I had lost my time... I personnaly want to contribute to stack overflow because when I try to answer a question I often learn something by doing research on it. I think it can be also usefull to retrieve some old answers we have posted to remember how we have resolve something.  According to me, our answers and the questions should be always visible in our account page, even if the user decided to delete them. Do you think it's possible ?  Is there a concrete reason to delete answers when a question is deleted ?


What would happen to a person's body if they entered a black hole?

One of the premises of the classic sci-fi show Farscape is that a person could travel through black holes, I'm curious as to what exactly would happen to a person body if you were to enter a black hole and how far out the premise of traveling through black holes really is?


The following "red" styles are prohibited, but are sometimes applied by LibreOffice Writer automatically. The following "red" styles are prohibited, but sometimes they are applied by LibreOffice Writer automatically.   Could somebody say which version is correct and sounds better? I tend to think that only the second one is grammatically correct in English, but I'm not really sure, and in my native language it would definitely sound cumbersome.


Subject-verb inversion / verb-subject-object -- is this correct?

I recently read the following in a schoolbook:     Wrote the researchers, "[...]"   I wonder if this is correct English. I have seen it a couple of more times. Is this just a matter of preference? English doesn't really have a very liberal word order, unless you're writing poetry or the like.  Can anyone tell me what this is called? I found some information on subject-verb inversion, but it only seems to be when the object is in front, but in this case, the word order is verb-subject-object.


Android application 'on hold'; 'duplicate';'closed' etc

I use android application to view question and answer them. Sometime i confuse with title of question which has been already marked on hold duplicate or closed. In web interface they get updated and shown in list (added to title in bracket)but in android app its missing. Am i missing something here?


Is there a way to connect my iPod touch to the internet without wireless connection (say, by usb)?

If I have no wireless connection, can I connect to the internet using the usb on the computer, or some other way?


How to know from where a function is called in Android?

Is there any way to know from where a function is called in Android ??  In my application (Its a huge one, that's source code is downloaded from the internet.) a set of functions executing. I cant figure out from where they are called !  Is there any ways ??


Potential Difference and Current dependence

When revisiting Ohm's Law, I wondered why (I know it's experimentally derived) the voltage change between two points would depend on current. I could understand this dependence with total energy dissipated in moving a current across a resistor but I can not understand why the P.D. (i.e. the work done per unit charge) depends on the current being passed. Essentially, I'm asking why does the amount of energy needed to move a single unit charge depend on how many charge carriers there are with it?


I have been given this question from my university to complete and I am having some trouble. The lecturer did not do a very good job of explaining the concept and I could not find any materials online to help so I came here. The question is-  What happens if you apply the method of steepest descent to  $f(x)=(x_1^2)+(x_2^2)+(x_3^2)$  Thank you.


Files (Nautilus?) shows the real location of Symbolic Links

I some of the "folders" in my home directory are symbolic links to a larger hard drive mounted on /mnt/data.   I would like it if when I click on (for example) Music in my home directory, Nautilus showed ~/Music. Instead it shows /mnt/data/Music. Not a bug exactly... but it would be nice if going "up" went back to my home directory instead of to the mount point.  Is there a way to change the behaviour of Nautilus in this regard?


How do I draw a little red square to label my right triangle?

The sample code:  \documentclass{minimal} \usepackage{tikz} \begin{document} \begin{tikzpicture} \draw  ( 0 , 0 ) coordinate (A)      -- ( 4 , 0 ) coordinate (C)      -- ( 0 , 3 ) coordinate (B)      -- (0,    0); \end{tikzpicture} \end{document}   The figure:    I would like to use a box in the lower left angle of the triangle to indicate a right angle.


Which word can describe programmer, coder and developer in computer science?

I have seen many questions here and there about programmers, coders and developers. Like "programmer vs coder vs developer" etc. All these words are having slightly different meanings. Can we describe them together using single word?  If yes what would that word be?  References:


Prove that sum of product of binomial coefficients is equal to 0

Show that $\sum\limits_{k = 0}^{n} (-1)^k C_n^k C_{3n-k-1}^{2n-k} = 0$ for any $n > 0$.  I've tried to prove it by induction, but it turns out to be not so easy.  I bet there is some natural solution without induction here. I tried to come up with some polynomials such that the coefficient of $x^{2n}$ in their product equals to the given sum and then to prove that actually it is zero, but didn't manage to do it.   Also I tried to apply Inclusion–exclusion principle here, but didn't find the way to do it in our problem.  Any help would be greatly appreciated.


Let $T\colon X\to Y$ be a linear operator with norm  $$\|T\|=\sup_{\|x\|=1}\|Tx\|.$$ Prove that  $$\|T\|=\sup_{\|x\|\leq 1}\|Tx\|.$$


Systemd start laptop even when lid closed

I use dropbear to activate laptop remotely and expect to detect SSH server port open after I login and decrypt disk remotely, but it seems that I have to leave laptop open for this to work, does anyone know how to work around this problem and startup correctly the default SSH server?  This problem is not “how do I ignore lid closed and avoid shutdown in that case”, it is opposite, how to ignore it already being closed when starting up.  I am on Debian 9 Stretch and here is how sshd service is set up so you don’t have to look up (so I want to reach multi-user target I guess)  [Unit] Description=OpenBSD Secure Shell server After=network.target auditd.service ConditionPathExists=!/etc/ssh/sshd_not_to_be_run  [Service] EnvironmentFile=-/etc/default/ssh ExecStartPre=/usr/sbin/sshd -t ExecStart=/usr/sbin/sshd -D $SSHD_OPTS ExecReload=/usr/sbin/sshd -t ExecReload=/bin/kill -HUP $MAINPID KillMode=process Restart=on-failure RestartPreventExitStatus=255 Type=notify  [Install] WantedBy=multi-user.target Alias=sshd.service


Let $X_1, X_2, \dots, X_n$ be $n$ positive iid random variables. Then show that $$E\left(\frac{\sum_{j=1}^k X_j}{\sum_{i=1}^{n} X_i}\right) = \frac{k}{n}.$$  Because of the linearlity of the expectation I known that $E\left(\frac{\sum_{j=1}^k X_j}{\sum_{i=1}^{n} X_i}\right) = \sum_{j=1}^k E\left(\frac{X_j}{\sum_{i=1}^{n} X_i}\right)$, so it's enougth to show $E\left(\frac{X_1}{\sum_{i=1}^{n} X_i}\right) = \frac{1}{n}$. But I'm unable to deal with the $X_i$ in the denominator.


Does layover for plane change require transit visa in usa?

I am travelling to Canada on a Migrant Visa. Flying Air India to Newark Liberty & by Air Canada from Newark Liberty to Toronto. Layover for a change of planes being 4hrs 20mins in Newark Liberty Intl. Would I require a US transit Visa for my travel?


How do I make a mirror in BI or cycles? I have very little experience with materials. I am just wanting to experiment with mirrors in Blender. For example, What I am thinking is to make two opposite walls inside a cube both mirrors. Can blender handle that or even 4 walls as mirrors?


My os is Fedora 24 and I tried to test the suid bit functionality.  I wrote below bash as Setuid.bash:  #!/bin/bash if [ $USER = 'root' ] then     echo "Like Root Run"     echo "Root User Add in " $(date) >> /etc/SetUid else     echo "Other User Run"     echo $USER "User Add in " $(date) >> /etc/SetUid fi   with -rwsrw-r-x. 1 root root 249 May 21 14:45 /bin/Setuid.bash permission and -rwx------. 1 root root 432 May 21 14:45 /etc/SetUid  Now, when I tried /bin/Setuid.bash as root I got:     Like Root Run   but when run that with Test user I encountered:     Other User Run      bin/Setuid.bash: line 8: /etc/SetUid: Permission denied   I'll appreciate if any one let me know, where is my way wrong?


Find all solutions to $1!\times 3! \times \cdots \times (2n -1)!=m!$   I have found $(n,m)=(1,1),(2,3),(3,6),(4,10)$  How can one prove there are no more? Also is it a coincidence that these are the triangle numbers? If not, why is this so? I cannot work it out.


Answer on really valuable review after rejection and invite reviewer into co-authorhship?

Let us suppose that we have received a rejection of our paper form a journal, but this rejection contains a really very valuable and detailed review, so some ideas of this review after some consideration and rethinking will be included into the new version of the paper.  And I here have two questions. No doubts: the new version of paper will contain acknowledgements to the anonymous reviewer. But:   Is it a good manner to answer editor's rejection letter and ask him to pass our deep appreciation to the anonymous reviewer? Is it somehow possible to ask the editor to pass our desire to invite this reviewer to be a co-author of our paper?


proof of an inequality $ \left( 1+ \frac{x}{p} \right) ^{p}$

Prove that for $x>0$  and $0<p<q$:  $$\left( 1+ \frac{x}{p} \right) ^{p}  < \left( 1+ \frac{x}{q} \right)  ^{q} $$


How much does someone absorb from the Sleep spell if they can't be put to sleep?

How much would someone absorb from the  spell if they can't be put to sleep? The spell states  This spell sends creatures into a magical slumber. Roll 5d8; the total is how many hit points of creatures this spell can affect. Creatures within 20 feet of a point you choose within range are affected in ascending order of their current hit points (ignoring unconscious creatures). Starting with the creature that has the lowest current hit points, each creature affected by this spell falls unconscious until the spell ends. [...] Subtract each creature's hit points from the total before moving on to the creature with the next lowest hit points. A creature's hit points must be equal to or less than the remaining total for that creature to be affected.  So what happens if an elf or a warlock with Aspect of the Moon (both are immune to magical sleep but not directly to the spell itself) is in the targeted area? Would it: A. Treat them like they don't exist B. Subtract their HP and then move on, leaving them awake or C. Let them absorb the full effect of the spell as regardless of their HP they can't be put to sleep  B seems the most likely but I feel like I've seen C ruled before in a game. A would also make some sense as well.


I am trying this code on the Firefox console, and I don't know how to get the correct answer(0.11). I would like to understand why this code doesn't work as I expected. Can someone help me understand. Thanks!    var a = "12,25";   var b = "12,14";    console.log("A: " + a);   console.log("B: " + b);    var parsedA = parseFloat(a.replace(',', '.'));   var parsedB = parseFloat(b.replace(',', '.'));    console.log('Parsed A: ' + parsedA);   console.log('Parsed B: ' + parsedB);    console.log("Dif Parsed Float: " + (parsedA - parsedB));    var numberA = Number(a.replace(',', '.'));   var numberB = Number(b.replace(',', '.'));    console.log('Number A: ' + numberA);   console.log('Number B: ' + numberB);    console.log("Dif Number: " + (parsedA - parsedB));


Java - Stacks using - private ArrayList list

I have researched stacks and have success using them in main with String or Integers. I can't seem to figure out what I am missing in my homework assignment. I continue to get a NullPointerException on my list.add(top, item). Am I forgetting something? I feel like I just need to understand what I am missing to finish the program. Once I can start pushing to the stack I think I am good to go.  The program does push: Enter a sentence, I will tell you if it is a palindrome:  test "t" is a here  Error:  Exception in thread "main" java.lang.NullPointerException at MyStack.push(MyStack.java:48) at CSCI254ProjectTwo.isPalindrome(CSCI254ProjectTwo.java:50) at CSCI254ProjectTwo.main(CSCI254ProjectTwo.java:22)    The below links makes sense and work fine for me:        public static boolean isPalindrome(String sentence) {     MyStack<Object> s = new MyStack<>(sentence.length());// declare a MyStack s     MyQueue<Object> q = new MyQueue<>(sentence.length());// declare a MyQueue q      String str;      for(int i = 0; i < sentence.length(); i++)     {         char temp = sentence.charAt(i);               if(Character.isLetter(temp)) // if ith character in sentence is a letter         {             Character.toUpperCase(temp);//convert to upper case and push it into s and q             str = Character.toString(temp); //i did this because I thought my issue was related to char which now I do not think is the issue             s.push(str);//*******************THIS IS WHERE I WANT TO PUSH TO THE STACK**             q.push(str);         }     }     while(!s.isEmpty())     {            if(s.peek() != q.peek()) // if the front of the queue not match the top of stack            {                return false;                 // return false            }            else            {                s.pop(); // pop out top of the stack and front of the queue                                 q.pop();            }     }     return true; }  import java.util.ArrayList; import java.util.List;  public class MyStack<E> {     //private ArrayList[] list;     private ArrayList<E> list; // used to store elements in stack // private ArrayList<E> testing; //private ArrayList[] test; private int top; // the index of top element private String[] stackArray; /**  * constructor construct an empty stack  */ public MyStack(int size)// {     //ArrayList<E> list = new ArrayList<E>(size);     List strLst = new ArrayList();     //List<String> testing = new ArrayList<>();     //new ArrayList<Object>();     top = -1; //empty stack     //test = (ArrayList[]) new Object[size];     //stackArray = new String[size]; }  /**  * push push a given element on the top of the stack  */ public void push(E item) {     top++;     System.out.println("\"" + item + "\" is a here");      //list.add(top, "E");     //stackArray[top] = item;     //System.out.println("\"" + stackArray[top] + "\" is a palindrome!");     //testing.add(top, item);     //list[top] = item;     //test[top] = (ArrayList) item;     list.add(top, item); **//****************HERE IS MY ISSUE** }


Do ability-boosting items or spells count for meeting feat prerequisites? I always reckoned that they do not. But now I wonder.  For example, the text for Gloves of Dexterity is     They add to the wearer's Dexterity score in the form of an enhancement   bonus   So it comes down to the question: does a bonus become part of the score itself? This seems logical in the case of an inherent bonus. The inherent bonus is just a means of keeping track of permanent magical boosting e.g. via wish spells. This kind of boost is limited to 5 points. As a DM I would judge that boosting an ability score via wish spells does count for meeting prerequisites for feats. But, if so: What is the difference to an enhancement bonus?  Ok, it may not be permanent. But there are rules what happens if you no longer meet prerequisites: the feat ceases functioning until you meet the prerequisites again.  This kind of ruling would even mean you could cast a boost spell before leveling up to meet prerequisites, take a feat and this feat only works while you have enough active boosts.  So my question: Do ability boosting items or spells count for meeting prerequisites for feats?


A process called "accountsd" is making my iMac Late-2013 unusable. Any ideas? (MacOS Catalina 10.15.7)

So, it has been a few days since my computer started having problems to open the google chrome browser. I checked the activity monitor and there is a process called "accountsd" which is using around 200% of the CPU power. Any suggestions? Thanks :D


how to get Personal Access Token from my integrated application LWC. I am using js only

I am using LWC for integration my application. I need to get the Personal Access Token at runtime. Is that possible to get?  Presently, I hardcode Personal Access Token in my LWC application. like this:   Http.setRequestHeader("Authorization", 'Bearer XXXXXXXXXXXXXXX');  i have clientId, ClientSecret, username and password. can i do auth 2.0 with it?  I am not able to get the Personal Access Token.


Configuring network on a fresh installed 18.04: RTNETLINK answers: File exists

I tried to install a new Ubuntu Server, but after the installation when I want to configure the network it didn't work using the Interface file. so i tried as per duplicate to set up the network with netplanbut thqt fqils too.  netplan file:  # Let NetworkManager manage all devices on this system network:   version: 2   renderer: networkd   ethernets:     enp3s0:       addresses:         - 193.171.201.236/27       gateway4: 193.171.201.225       nameservers:           search: [pro2future.at, pro2future.eu]           addresses: [140.78.2.62, 140.78.3.62]   How should I proceed?