I messed up the tip on my soldering iron. Is there any saving it?

I accidentally left my soldering iron, an XYTronic 258, on all night last night, set to a pretty high temp setting. Today I found that the tip was all oxidized and pitted looking. I tried cleaning it, I tried re-tinning it, but to no avail. Then I tried sanding and finally filing the tip. I got down to clean metal, but solder won't stick to it any more.   Did I ruin the tip? This is for hobby use, and I don't know of any places locally that sell tips for this iron. I'd really rather not wait a week for a replacement tip.  I read on other threads here that the tip is iron coated in Copper. Is that correct?   Is there anything I can do to rejuvenate the tip, short of getting some copper sulfate and electroplating a copper coating on it? Or is even that hopeless? I have stuff I'd like to solder this evening, but the heat transfer stinks now.  I have a fixed temp Radio Shack soldering iron that this one replaced (along with a fresh tip for that one) but my memory is that it is dreadful. The tips are not interchangeable between them, either.  It looks like my iron is variable power rather than thermostatic. It sounds like what I really need is a thermostatically controlled iron. Is there a moderately priced iron my readers can recommend? (I've been doing a lot of electronics lately, using it several times a week, and do end up doing electrical/electronic soldering a few times a month even when I'm not in the middle of an electronics project.) And what should I expect to spend on a decent iron for electronics and general electrical soldering?


Google Indexed demo site with same content

I have two server one is production abc.com other demo.abc.com problem is Google has indexed the demo server as well.   What is fastest possible fix to it and to remove it from Google index?  What harm it has given to my live site and is that possible to recover in future?  Thanks


Ubuntu 18.04.3 crashes on VirtualBox VM in Windows 10 Pro (1903)

My system is:   Dell Latitude 7400 i5-8265U with Windows 10 Pro (1903) VirtualBox 6.0.12 Ubuntu-18.04.3-desktop-amd64 1024MB RAM is assigned to VM (by default).   After clicking on "Try Ubuntu or Install", Ubuntu 18.04.3 crashes, the screen freezes/goes to full black, and nothing else.  What's the solution?


How to install 32 Bit Wine on 64 Bit Ubuntu?

Currently I'm running Ubuntu 11.10 64 Bit on my laptop and I want to install some Windows programs with Wine (Dreamweaver CS5/Starcraft II etc) but these programs require the 32Bit version of Wine to work even being in a 64Bit environment... I'm a Fedora user most of the time and in that distro installing 32Bit versions of apps inside of a 64Bit system is never a problem, but didn't find a way to do that on Ubuntu.


I have just learned from what I consider a reliable source, that the following sentence is correct:     One of us is wrong, aren't we?   I would never in my life have written this, but I am assured that   As I realize comments don't live forever I will quote the relevant parts:     oerkelens : So you  would really write One of us is wrong, aren't we? I guess by analogy you would not bat an eyelid at One of these balls is blue, aren't they?   Matt Эллен : yes, "Then one of us is wrong, aren't we?" is exactly how it would be written. Same for the balls.   Could someone please enlighten me how it is possible that the number in a question tag supposedly has to be in discordance with the subject of the main clause?  I admit that I am not the youngest any more, and my school days are long gone, but back in the days, I was taught that  1. a verb and its subject concord in number 2. a question tag concords with the subject of the main clause  I was given examples like:     It is warm today, isn't it?   We will be on time, won't we?   Mary is pretty, isn't she?   John isn't the brightest, is he?   Some people may notice that the subject of the main clause seems to determine every time the subject of the question tag. When the main clause subject is singular, so are verb and subject in the question tag.  I was under the impression that a) this made sense and b) this would be a general rule.  I fully realize that grammar does not have to make sense, so a) is immaterial. As for b), today I learned I was wrong :)  So when (and possibly why?) do we form question tags that are different in number from their main clause?   To exemplify, also the other example sentence that I used and was corrected on:     One of these balls is blue, isn't it? (so this is wrong)   One of these balls is blue, aren't they? (and this is correct)   As an afterthought, does this strange grammatical number mix-up only appear in question-tags, or should I always refer to singular subjects in the plural if certain conditions are met? And what are those conditions?  Which versions are correct?     One of the cars is broken, aren't they? They (the car(s?) that is(are?) broken) should be fixed.   One of the cars is broken, aren't they? It (the car that is broken) should be fixed.   One of us must be wrong, mustn't we? We (the one(s?) that is (are?) wrong) should make amends.   One of us must be wrong, mustn't we? He (the one that is wrong) should make amends.   (In the last one, they could of course be used as the singular they, but that would avoid the issue...)


What is the intuition behind gamma distribution?  For instance, I understand how to "construct" Gaussian distribution. This is my intuition:   Bernoulli distribution - which is simple concept A sequence of Bernoulli trials is a Binomial distribution. I understand how binomial coefficient is constructed Using Stirling approximation we can deduce Gaussian distribution   Hence I understand that shape of a Gaussian distribution is determined by the binomial coefficients and so on.  How can Gamma distribution be derived step by step using relatively simple concepts?


Where are crontab files stored in OS 10.8

I've already looked at this question:    But there is no real answer except for 10.7.  I'm trying to migrate crontab from an old drive that I can't boot so using crontab -e is out of the question.  Just need to read the user crontab file to pull existing jobs to a new server.


Show that $\left( 1+\dfrac {1} {n}\right) ^{n}$ is increasing

I see intuitively $\left( 1+\dfrac {1} {n}\right) ^{n}$ is increasing but I think, it is not obvious. How can I prove this?    Recall. If sequence of $\left\{ x_{n}\right\} _{n}$ is increasing then $x_n<x_{n+1}$ for all $n\in\mathbb{N}$.  Note that the limit converges to $e$ (Euler's number).


Using definition of derivative to differentiate $f(x)= \sqrt{x}+1$

Using $$\frac{f(x+h)-f(x)}{h}$$ how would I find the derivative of $f(x)= \sqrt{x}+1$   The answer is $$\frac{1}{2\sqrt{x}}$$ but I keep getting $$\frac{1}{2 + 2\sqrt{x}}$$


Looking for Cantor's original proof of the Cantor-Bernstein theorem that relies on the axiom of choice?

Even a sketch of it would be good enough. Thanks.


Shared sub-directory between multiple users

I have two users with home directories:  /home/user1/ /home/user2/   I would like to share a folder between the two users:  /home/user1/some/path/to/folder   but would only like user2 to have access to /home/user1/some/path/to/folder and not any of the parent directories.  I tried to chmod 777 /home/user1/some/path/to/folder, but that didn't work.


1  How to do that?  2  How to approach this?  Do these sentences need interrogative mark?   In what cases, ? symbol can be avoided? Suppose sentence start with How as in above two sentences.


If $a-b$ divides the difference $f(a)-f(b)$, must $f$ be an integer polynomial?

Background: Suppose $f:\mathbb{Z}\rightarrow\mathbb{Z}$ is an integer polynomial. Then $a-b|f(a)-f(b)$ for distinct integers $a, b$. This can be proven by induction on the number of terms in $f$ as well as the degree for monomials. However, what if we consider the converse? If $f:\mathbb{Z}\rightarrow\mathbb{Z}$ is a function satisfying $a-b|f(a)-f(b)$, must it be an integer polynomial? Must it even be a polynomial?


I have lots of windows programs in .exe because i've changed windows 7 to Ubuntu 12.04. Help please


We are displaying few charts on an excel sheet.  How to remove the scroll bars, row numbers and columns headers from excel web access webpart?


Is it possible to add a Lightning Web Component to a Visualforce Page in Salesforce Classic?

My employer is planning a transition to Lightning Experience in the coming months, so I have been learning to develop LWCs and practicing with real projects. I am wondering if it is possible to add those components I have developed to a Visualforce page for use in our org before we roll out Lightning to our users. If so, what is best practice?


Bijections as the composition of 2 involutions

How can we prove that any bijection from any set to itself is a composition of 2 involutions ?  So I know that any involution is a bijection, and so it has an inverse (which happens to be itself here). Also, I was thinking that maybe we could use the identity function on the set somehow because the identity function is also an involution right ?  Also the case where the bijection in the question is already an involution is trivial since we can take the composition of itself with the identity.  Thanks for your help.


As far as I know, there are no special conditions other than this is a space with only real numbers. I'm not sure how to move forward with the problem. I know that $x^2 = |x|^2$ but I don't know how to make use of that.  $2|xy|≤ x^2 + y^2$


If $f_1(z), ···, f_n(z)$ are analytic in domain $D$, and continuous to its boundary. Prove that  $ \varphi (z) = \lvert f_1(z) \rvert + ··· + \lvert f_n(z) \rvert$ is continuous and achieves its maximum value on the boundary.  The question emerges in the chapter "taylor series" from the book, but I have no clue.


prominently sports purple hair.    Is this her natural hair color?  Natural extensions in the answer depending on the correct answer: Is she wholly human and humans in the Galaxy Far Far Away can have this hair color?   Or is she partly human or not human?   Or does she dye her hair?   Or is there another hair color changing technology?


Cannot translate vertice/edge will duplicate

Most of the time when I try to move a vertex or an edge, instead of translating that, it extrudes it, it creates another face or, vertiex or whatever. I do not really get why it behaves like that. I hope I explained it in depth. I am sorry if this is a duplicate post but I could not find anything!


Why the forward bias voltage of a silicon diode is 0.7V?If we apply a voltage of 0.1V then the depletion region will be minimized.In a diode there is the chemical potential which creates diffusion and there is the electrostatic potential created by the donor and acceptor ions.So if we apply a small voltage which will help the cjemical potential then the majority charge carriers of the n-type semiconductor will diffuse into the p-type semiconductor and the depletion will be destroyed.Where am I wrong?


Anyone have a good resource or provide a sample of a natural order sort in C# for an FileInfo array?  I am implementing the IComparer interface in my sorts.


Why is $\lim_{n\rightarrow \infty } \frac{\sum_{i=1}^{n} 2^{1/n}}{n}$ equal to 1?

As the title states, why is this? The original sequence is $b_n=\frac{2+\sqrt[]{2}+\sqrt[3]{2}+\cdots +\sqrt[n]{2}}{n}$, however:  $$b_n=\frac{2+\sqrt[]{2}+\sqrt[3]{2}+\cdots+ \sqrt[n]{2}}{n}=\frac{\sum_{1}^{n} 2^{1/i}}{n}\Rightarrow \lim_{n\rightarrow \infty } b_n=\lim_{n\rightarrow \infty } \frac{\sum_{1}^{n} 2^{1/i}}{n}$$ I would assume $\sum_{1}^{n} 2^{1/i}$ to converge to an $a$, as $lim_{n\rightarrow \infty }\sqrt[n]{2}=1$, so that $\lim_{n\rightarrow \infty } \frac{a}{n}$ would go to 0, however, the result is 1, why is that? And, how could I properly evaluate this expression?


Sobject Get on Relationship fields : Invalid Field

I am working on a module where I have to create complex nested JSON dynamically based upon configs stored in custom metadata, The metadata contains Object name, fields names as text fields.  Now the problem I am facing is I can't use Sobject get on relationship fields, it gives runtime error.  Minimum viable code to reproduce:  Opportunity opp = [Select id,Account.Name from Opportunity Limit 1][0]; opp.get('Account.Name');   Exception:      Error on line 2, column 1: System.SObjectException: Invalid field   Account.Name for Opportunity AnonymousBlock: line 2, column 1   How can I dynamically access relationship fields using Sobject get?


I just installed Ubuntu 14.04 and have tried to configure the adapter which is a Linksys WUSB6300, but seem to have no response. I have tried using the startup CD to activate the adapter but seem to get only errors.


How can I see a read out of my CPU or in general how much my laptop is overheating? I tried this () where all the temperature info is shown when you type "sensors", but I'm not getting anything -   I have Ubuntu 14.04 and I don't know anything about it so what can be the problem? I also noticed I can't run new programs like Blender (donloaded as as ZIP so it doesn't require instalation). How can I check if I have a limited version of the OS because I believe it shouldn't work like this. Here's the program folder -   I'm just plain confused, please help!


I have a problem. I want to make a generic method to convert my errors enums to specific response. for instance my response object  public class ErrorResponse {     public ulong Code { get; set; }     public string Description { get; set; }     public string OrigionationSystem { get; set; } }   and I want to convert my all errors to this response for eg  public enum ProductErrors:ulong {     None,      [Description("Prouct Not Found")]     ProductNotFound,      [Description("Invalid Product Isbn")]     InvalidIsbn }  public enum CustomerErrors:ulong {     None,     AlreadyExists,     InvalidEmailAddress }   and now i want to make generic method to convert my enums to ErrorResponse. previously i was using this method to convert my error codes to error response.  public static IList<ErrorResponse> ParseErrorCodeToErrorResponse(this IEnumerable<ProductErrors> errorCodes) {     return errorCodes.Select(x => new ErrorResponse     {         Code = (ulong)x,         Description = x.GetDescription(),         OriginatingSystem = Extensions.GetCurrentSystemName()     } ).ToList(); }   problem raise here :   public static IList<ErrorResponse> ParseErrorCodeToErrorResponse<T>(this IEnumerable<T> errorCodes) where T : struct, IConvertible {     if (!typeof(T).IsEnum)     {         throw new ArgumentException("T must be an enumerated type");     }     return errorCodes.Select(x => new ErrorResponse     {         Code = (ulong)x,         Description = x.GetDescription(),         OriginatingSystem = Extensions.GetSystemName()     }).ToList(); }   when it's for only one enum it's working fine but when i made it generic it said      Type T can't convert to ulong and on x.GetDescription() it is saying can't resolve GetDescription()


How to remove unwanted list brackets from within a list?

What would be the most pythonic way to convert the below list of lists into a single list? [['MyValue1'], ['MyValue2'], ['MyValue3']]  Desired output" ['MyValue1', 'MyValue2', 'MyValue3']  Thank you in advance!


How long are the life phases of a dragon?

The life phases of a dragon in 5th edition D&D are:   Egg Wyrmling Young Adult Ancient   Given that a dragon lives for at the least 15-ish centuries, up to I think well over two thousand years, how long does each phase of their life last?


How to make a domain receiving email behind cloudflare?

I have a web server hosting multiple domains (centos + postfix + dovcot), one of my domain  its dns is hosted on cloudflare (ie. abcd.com), but when I use gmail to send email to a user@abcd.com, user@abcd.com will not be able to receive the email. Here is the MX record I set in cloudflare:  Type   Name   Value                                       TTL          Active mx     mail   handled by mail.abcd.com with priority10    Automatic      cname  mail   is an alias of abcd.com                     Automatic    grey cloud   Any knows how can I make the domain receive the emails?


random number generation and probability problems

I recently ran into two problems:   given a rand() function that generates 0 and 1 with 50% probability respectively (binary outcome), how to write some code to generate 1 with 90% of the chance and 0 with 10%?  There is a society where people will NOT stop having babies until they have a boy. What's the ratio of boys and girls in that society? Consider it's equal probability to have either a boy or a girl.    If possible, please advise what kind of background prob/stats materials these relate to. Thanks!


Files with the extensions .ts show up in finder as the kind "MPEG-2 Transport stream".   However I am developer and they are are actually text files, specifically TypeScript.  I tried changing the app associated with the files but that does not change the "kind".  Is there anyway I change the kind that MacOS associates with the extension .ts.   As when I use Spotlight and use "kind:movie".  All these text files show up.


I am getting a deal on a Canon T3 cam with 18-55mm kit lens and I have choice of one extra lens: 75-300mm f4-5.6 and 55-250mm f4-5.6. I generally like to shoot street, abstract and nature photos and I'm not sure which lens is going to be more suitable to my needs. Are their pros and cons to either lenses given my preferred subjects?


Everyone knows the story about countersteering. For those who don't, I will explain it below and after the explanation I will ask my question.  You can watch this short video as a beginning:   .  This an excellent graphic demonstrating what is happening:    The key is that moving your butt moves the CG ($y$ and $x$ are the location in the image.) Basically what has to happen is for the moments created from the weight ($mg$) and the centrifugal force $\left(\frac{mv^2}{r}\right)$ to cancel out. (A moment is a force times a distance, in this case the distance to the contact patch in the direction parallel to the force - $mg\times y$ for weight, $\frac{mv^2}{r}\times x$ for centrifugal force.). You can express $x$ and $y$ with sine and cosine times the distance from the contact point to CG. Then the bike goes around the corner and sparks fly from your titanium knee sliders. You can speed up and lean over (or drop your butt) until the centrifugal force equals the maximum force that the tires/road combination can handle. This is of course assuming that you're not doing anything else like braking or accelerating which takes away from the grip available for cornering. If you want the equations to play with: $\frac{mv^2}{r}\times y = mg \times x , m = mass$, cancels out! It doesn't matter how fat your ass is for computing the speed/turn radius, just where it is and the ratio of ass fat to bike fat (it does matter for maximum speed though) -> $v =$ velocity -> $r =$ radius of turn -> $y =$ vertical distance of cg from center of rotation (contact patch) -> $g = $ acceleration due to gravity (constant $9.81$ $m/s^2$) -> $x = $ horizontal distance of CG from center of rotation The two forces are trying to rotate the bike in opposite directions which is why the are on opposite sides of the equation. so: $v = \sqrt{\frac{rgx}{2y}}$ OR $r = \frac{2yv^2}{gx}$ You can see that as $y$ drops or $x$ gets bigger (lean over more or hang off more for both, basically) either $r$ has to go down (tighter turn) or $v$ has to go up!  Now comes my question. In ALL explanations (including my own) the centripetal force in the picture (free body diagram) is pointing outwards. But this doesn't make sense, because the centripetal force should point inwards. Then you get the problem that BOTH torques try to turn you to the inside. In practice we can obviously see that this doesn't happen. So you would say that in this case the centripetal force (better: centripetal torque) is pointing outwards. How is this possible? I have always learned that the centripetal force should point to the centre of the circle. Please help !!!


I've just purchased a new Olympus E-M1 Mark II from Jessops as Brand New.  It's my first semi-expensive camera so I'm looking for opinions. At the moment there is a promotion that gives you cashback when you purchase this camera, as with all my products I'll register the warranty as soon as I receive it, did the same with the cashback.   In this case I decided to check the shutter actuation's as recommended by a friend but slipped my mind until I've submitted the warranty etc.  The MS: 347  Have spoken to Jessops and they say there is nothing they can do (In terms of a refund or replacement) as I've registered the product and can only offer me £15 for the trouble.  So my question's are:   Is this normal? If it isn't, how much should I be asking for back? (Body was £1400).   Thank you all.


Correct and simplest syntactical way to initialise an array to 0

I am trying to find out the correct way to initialise an array to all zeros (i.e. as if you have done a memset on the array).  I have found the following methods from various areas in stack overflow (and other sources):  char myArray1[10] = {0}; char myArray2[10] = {0,}; char myArray3[10] = {[0 ... 9] = 0}; char myArray4[10] = {0,0,0,0,0,0,0,0,0,0};   I would prefer the simplest syntax variant... I was using {0}, but I have not found any proof this actually is correct.


Transvection matrices generate $ \operatorname{SL}_n(\mathbb{R}) $

I need to prove that the transvection matrices generate the special linear group $\operatorname{SL}_n \left(\mathbb{R}\right) $.  I want to proceed using induction on $n$.  I was able to prove the $2\times 2$ case, but I am having difficulty with the $n+1$ case.  I supposed that the elementary matrices of the first type generate $\operatorname{SL}_n(\mathbb{R})$. And I want to show that an elementary matrix of the first type of order $n+1$ can generate $\operatorname{SL}_{n+1}(\mathbb{R})$


polynomial such that p($\sqrt2$+$\sqrt3$)=0

Are these following exercises equivalent?   Let $\mathbb R$ be an extension of $\mathbb Q$.Find a polynomial p(x) in $\mathbb Q$[x]-{$0$} such that p($\sqrt2$+$\sqrt3$)=$0$.   and  2.Find the minimal polynomial of $\sqrt2$+$\sqrt3$ over$\mathbb Q$[x]


dead key after switching two keys with xmodmap

My keyboard switches the (German) keys [^] and [<], so I want to switch the two keys.  I identified the keycodes using xev and created a file ~/.xmodmap containing  keycode 94 = asciicircum degree keycode 49 = less greater   When executing xmodmap ~/.xmodmap hardware key 94 now correctly outputs "^" instead of "<". Unfortunately the other key does not output any character at all.   xev returns the following output when the key is pressed  KeyRelease event, serial 32, synthetic NO, window 0x2e00001,     root 0x4b, subw 0x0, time 258843335, (169,-12), root:(185,111),     state 0x4000, keycode 49 (keysym 0x0, NoSymbol), same_screen YES,     XLookupString gives 0 bytes:      XFilterEvent returns: False   do you know what the problem might be?  As far as I understand it the  says that remove only works for modifiers, but I don't care for modifiers, I want to switch regular keys. Might there be another problem that is not related to that 'possible duplicate'?


How to change JLabel when JButton is clicked?

import java.awt.*; import java.awt.event.*; import javax.swing.*;  public class JCalculator implements ActionListener {  private JButton[] buttons; private JLabel display; private String[] button_Shapes; //private String s0, s1, s2;  //Create new form Calculator public JCalculator(){      //Create new JFrame container     JFrame jfrm = new JFrame("Calculator");      //Set the initial size for frame     jfrm.setSize(500,500);      //Terminate the program when the user closes the application.     jfrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);      //Set the calculator to center on the screen     jfrm.setLocationRelativeTo(null);      //Set the icon     ImageIcon icon = new ImageIcon("C:/Users/zetsu/Desktop/JCalculator.png");     jfrm.setIconImage(icon.getImage());      //Create label     display = new JLabel("0", JLabel.RIGHT);       //Put border around display label     display.setBorder(BorderFactory.createLineBorder(Color.black));      //Create a grid layout     GridLayout layout = new GridLayout(4,4);      //Create a panel and set layout     JPanel bottom_Panel = new JPanel();     bottom_Panel.setLayout(layout);      //Create an array of buttons     buttons = new JButton[16];              //Put buttons in an array     String[] button_Shapes = {"7", "8", "9", "/", "4", "5", "6", "x", "1",                      "2", "3", "-", "0", "C", "=", "+"};      for(int i = 0; i < button_Shapes.length; i++){         //make new button name         JButton btn = new JButton("" + button_Shapes[i]);         buttons[i] = btn;         //add action listener for each button         btn.addActionListener(this);         //add each button to panel         bottom_Panel.add(btn);     }      //Set [=] button to default     jfrm.getRootPane().setDefaultButton(buttons[14]);      //Set Mnemonic to Alt+[C]     buttons[13].setMnemonic(KeyEvent.VK_C);      //Add label to content pane     jfrm.add(display, BorderLayout.NORTH);      //Add panel to content pane     jfrm.add(bottom_Panel, BorderLayout.CENTER);      jfrm.setVisible(true);  }  @Override public void actionPerformed(ActionEvent e) {     //try left operand, operation, right operand     Object event = e.getSource();     if(event == buttons[0]){         display.setText(""+button_Shapes[0]);     } }  public static void main(String[] args){     SwingUtilities.invokeLater(new Runnable(){         public void run(){             new JCalculator();         }     }); }   }   Program Description:      Implement a simple integer calculator with the following features:         Center the calculator on the default screen at startup.   The display must have a border.    All the operations are in the form:    (operand1 operator1 operand2 =) operator2 operand3 =   The [C] button will clear the calculator, eg. initial state. Must support Alt+[C]    Ctrl+[C] Ctrl+button combination will display “(c) your-name”   Only the [C] button can be used to restore the current display.   The [=] button is the default button.    The result can be negative.    Only allow up to 8 digits.    Display error such as “Overflow”, “Div by 0”, …, and the [C] button will clear the error and reset the calculator.    Use JCalculator.png as the program icon.       I am trying to write a program to create a swing gui of a simple calculator. I want the number clicked to show up on the label. However, I keep receiving NullPointerException error whenever I click the number. I think the actionPerformed part is wrong but I'm not really sure.


Uniqueness of $k$th root mod $m$ if $(k, \phi(m)) = 1$.

I'm trying to prove a fact about $k$th roots that says that if $(k, \phi(m)) = 1$ and $(b,m) = 1$, then there is a unique $k$th root modulo $m$ (composite $m$).   I'm not sure how to go about it but here's an attempt;  Suppose towards a contradiction that there are two solutions $x_1 = b^r$ and $x_2 = b^s$ to the congruence $x^k \equiv b \bmod m$. Then $$x_1^k \equiv x_2^k \equiv b \bmod m$$  so that $b^{kr} \equiv b^{ks} \equiv b \bmod m$, or equivalently, $b^{kr - 1} \equiv b^{ks - 1} \bmod m$. We can then conclude that $m \mid b^{kr - 1} - b^{ks - 1}$. Now we can factor to obtain $b^{kr - 1} - b^{ks - 1} = b^{kr - 1}(b^{k(s-r)} - 1)$ to conclude that $m \mid b^{kr - 1}(b^{k(s-r)} - 1)$. But since $(b, m) = 1$, we must have $m\mid b^{k(s-r)} - 1$, or equivalently,   $$b^{k(s-r)} \equiv 1 \bmod m$$  which would imply $k(s-r) = \phi(m)v$ for some $v \in \mathbb Z$.  I feel like there could be a way to extract a contradiction from this last step but I can't see it, would somebody be able to check if this is a good way to go?


how to move or copy specific file quantities to other directory

I would like to know how to move or copy specific number of files to another directory.  For example: If I have 880 files in directory A and want to move or copy 150 files from A to directory B and also 150-300 files from A to directory C.  I already tried this command   $ find . -maxdepth 1 -type f | head -150 | xargs cp -t "$destdir"   But this is copying 880 files to directory B


code says: Exception in thread "main" java.lang.NullPointerException when I try to run

it keeps saying   Exception in thread "main" java.lang.NullPointerException     at jframe.game.JFrameGame.main(JFrameGame.java:29) Java Result: 1   whenever I try ro run the code and I have no clue why. also ive been using this video tutorial series:   package jframe.game;  import java.awt.Canvas; import java.awt.Dimension; import java.awt.Graphics; import javax.swing.JFrame;  public class JFrameGame extends Canvas implements Runnable{     int height = 500;     int width = 500;      private JFrame frame;     private Thread thread;     private boolean running = false;      public synchronized void start(){         running = true;         thread = new Thread((Runnable) this);           thread.start();      }      public static void main(String[] args) {         JFrameGame thegame = new JFrameGame();          //frame = new JFrame();          thegame.frame.setResizable(false);         thegame.frame.setTitle("hello frame");         thegame.frame.add(thegame);         thegame.frame.pack();         thegame.frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);         thegame.frame.setLocationRelativeTo(null);         thegame.frame.setVisible(true);          thegame.start();     }      public void run(){          while(running == true){             System.out.println("running the run method");         }      }      public JFrameGame(){         Dimension size = new Dimension(500, 500);         setPreferredSize(size);      }  }


How do I get the current bandwidth speed of an interface from the terminal?

I want to get the current Bandwidth of an interface say "eth0" from the terminal. It better be as simple as possible. Say          up 10 dn 30. Instead of giving out a lot of text like "vnstat" does.    Edit: I need this for a command line program for auto-monitoring, not to view it manually.


Translation mess up with fields which are not translatable used in views

Example set up:  Content type news with fields   Body (translatable) date (another date field beside node published date - translatable) type of news (list field - not translatable, the news should be of the same type in every language)   View with filters:   Published: yes Content type: news Content language: currently activated interface language field "type of news" -> exposed to the user   Default language in the project is German.  When I go to the view in German and choose a type of news in the exposed filter there is no problem - the expected news are listed. The problem appears when I enter the page in English and I choose a type of news -> no results are found although the same nodes are translated into English.  I found out that this is due to the fact that the "type of news" values in the fields table are saved with the language id of the original node which is 'de' but the full view query expects the field value to have a language code 'en' (like the currently activated language has).  See this query and especially the INNER JOIN:   SELECT node__field_date.field_date_value AS node__field_date_field_date_value, node_field_data.nid AS nid, node_field_data.langcode AS node_field_data_langcode FROM {node_field_data} node_field_data INNER JOIN {node__field_news_typ} node__field_news_typ ON node_field_data.nid = node__field_news_typ.entity_id AND (node__field_news_typ.deleted = '0' AND node__field_news_typ.langcode = node_field_data.langcode) LEFT JOIN {node__field_date} node__field_date ON node_field_data.nid = node__field_date.entity_id AND (node__field_date.deleted = '0' AND node__field_date.langcode = node_field_data.langcode) WHERE (( (node__field_news_typ.field_news_typ_value = 'press') )AND(( (node_field_data.langcode IN  ('en')) AND (node_field_data.status = '1') AND (node_field_data.type IN  ('news')) ))) ORDER BY node__field_date_field_date_value DESC LIMIT 10 OFFSET 0   You may see that the inner join expects the langcode field in node__field_news_typ to be the same value as node_field_data.langcode which is 'en' when I enter the view in English. But looking into the table of node__field_news_typ I do not find one entry with 'en' as the field is not set to be translatable and all the nodes are originally written in German.  Maybe I did not get some basics of the multilanguage architecture in Drupal 8 but I find it a little bit strange that fields which are not translatable filter out nodes in views where a filter is set to "current active language". Is there not UNDEFINED_LANGUAGE ('und') anymore? Why do fields get a fix languagecode when they are not translatable? How can I avoid this behavior?   It seems to me that there is no other way as setting the field to translatable although I want to assure that translated nodes have the same value?!


Matrix doesn't shrink when put in fraction.

This is my minimal example, the problem is the different size of the two x. I would expect the matrix to be shrunken too, but it isn't. Why is this and how is it corrected?  \documentclass[a4paper,12pt]{article} \begin{document} $\frac{\begin{pmatrix}x\end{pmatrix}x}{2}$ \end{document}   edit: I just realized: this is not matrix specific. \underbrace does it too. seems like the information to be smaller doesn't get through these "frames":  \documentclass[a4paper,12pt]{article} \begin{document} $\frac{\begin{pmatrix}x\end{pmatrix}x}{2}e^{\begin{pmatrix}x\end{pmatrix}x}\int_{\begin{pmatrix}x\end{pmatrix}x}$ $\frac{\underbrace{x}x}{2}e^{\underbrace{x}x}\int_{\underbrace{x}x}$ \end{document}


How to set unlimited scrolling on a TTY?

On  a TTY ( ctrl+alt+f1 to f6 ), I use Shift+page up to scroll up and Shift+page down to scroll down. But the problem is, the scrolling is limited to certain number of lines.   How can I get unlimited scrolling on a TTY ?


Spam sent from my domain after a Wordpress exploit

I have 2 domains on my dedicated server running debian.  One of them is linked to a wordpress site, mydomain.com.  I've noticed that on both my sites, lately, the performances were horrible so I started to look for a reason.  I noticed that in the last few days, my daily syslogs were as big as 800mb, filled with notices of deferred emails coming from emails looking like name_surname@mydomain.com, obviously programmaticaly generated.  I updated my wordpress, deleted the deferred queue (all 130 000 deferred mails making it) of postfix, and waited 10mn.  After 10mn, the queue is filled with 4000 mails and counting, and can't locate any fishy script anywhere.  I can't find any information about such an exploit, so I'd like to know what I could do get rid of that spam that is killing my server.  If that can help, it seems that every address sends batches of 20 emails.


What will be the size settings in photoshop of 4x6 feet?

I want to make a family tree more in font (minimum of 12pts) of 4x6 feet for a poster sticker so what will be the size settings in photoshop?


Removing artifact from PDF figure in LaTeX, compiled with pdflatex

I am working on a document in LaTeX, and when inserting pdf figures I get a weird black line down the right side.  This is not present in the original pdfs (I've checked).  I thought it might be some scaling issue, since several of my figures are large and I have to scale them smaller than actual size in LaTeX, but it also appears in this figure, which is actual size. My code for the figure is:  \begin{figure}[t] \includegraphics[height = 9.6cm]{"testschema"} \caption{Database Schema for test case, simulating results from a test suite} \label{fig:schematest} \end{figure}   And the output after compiling with pdflatex is:


Is first authorship a big deal (in terms of highlighting it on CV, etc.)?

From August 2015 through August 2016 I was on a Nuclear/Radiation Physics based work placement in a scientific research institute, between my second and third years of my university Maths degree. I am now back at university, half way through my third year.  About half way through my work placement (which I thoroughly enjoyed), my supervisor suggested that the work I was doing could be considered publishable. Being an undergraduate this was (and is) obviously a very exciting prospect. It turned out that we did decide to write a paper, and my supervisor said to be that I would get to be the first author. I don't understand much, but I'm under the impression that's something to be excited about too.  I finished with all the analysis and wrote a draft of the paper. It was then time for me to leave my placement and my (now ex-)supervisor are still in correspondence, whilst he finalizes the paper. There have been various (unrelated) issues which have held him back from spending time on it - but he suspects (as it stands) that he will possibly finish it and submit it to a journal by the end of February. He's basically completely reformatting a lot of the paper, and probably rewriting a whole bunch of it, because being an undergraduate I have no idea how to write a paper. Of course this means that if I do turn out to be first author, my supervisor has probably been very generous.  Long story short - if things go well and the paper is accepted in whichever journal, is this a big deal or nothing to be so bothered about? I ask basically to figure out where this ranks in terms of putting it on a C.V. (or something). Is this something to simply add on as an achievement, or something to really highlight?   I understand my question is really rather ambiguous. Essentially I'm really not sure what to expect under the circumstances that the paper is published - if anything.


I'm on SQL Server 2014 and I have a User table:  +----+------+-----+ | ID | Name | ... | +----+------+-----+ | 11 | John | ... | | 12 | Jack | ... | | .. | .... | ... | +----+------+-----+   And I have many tables which references this one. Can I get a list of all tables which references this table? And, in particular, can I get a list of all tables which references a particular row on this table?  I will then need to update all references to User 12 to User 11.


Is there a number $n$ such that there are exactly 1 million abelian groups of order $n$?   Can anyone please explain. I would yes because numbers are infinitive, and so any number n can be expressed as a direct product of cyclic groups of order n.  Can anyone please help  me understand.  Thank you.


Expressions - is there an easy and "visual" way to combine them into another expression?

I started to use expressions to encapsulate business logic and be able to pass it to EF directly. However I can't figure out how to "nicely" combine and/or reuse expressions in another expressions. For example, I have the following 2 business rules for valid products and clearance products: internal static Expression<Func<Product, bool>> fnValidProduct = (p) =>         p.DoNotDisplayProductsOnSite == false &&         p.CategoryId != null          internal static Expression<Func<Product, bool>> fnClearanceProduct = (p) =>          (p.ProductFlags & ProductFlags.Clearance) > 0 && p.Qty > 3;  However, I cannot figure out how to make a rule for "valid clearance products" using these building block. Code below won't compile for expressions: internal static Expression<Func<Product, bool>> fnValidClearanceProduct = (p) =>         fnValidProduct(p) &&         fnClearanceProduct(p);  I've looked into this sometime ago, and I even recovered some codes which I can't really understand now - which really defies the purpose of combining expressions: internal static Expression<Func<ProductContainer, bool>> fnValidProduct {     get     {         var parameterExpression = Expression.Parameter(typeof(ProductContainer));         var propertyOrField = Expression.PropertyOrField(parameterExpression, nameof(ProductContainer.product));         var combined = Expression.Lambda<Func<ProductContainer, bool>>(Expression.Invoke(fnValidProduct, propertyOrField),             parameterExpression);         return combined.Expand();     } }  Question is then - is there a way or NuGet libraries or something - to achieve that "code reuse"?


How to prove that the Einstein velocity addition is a one-parameter composition formula of a one parameter group?


All groups where underlying set has at most 4 elements

I have this homework problem.  It states:  By constructing the possible Cayley tables, list all groups where the underlying set has at most 4 elements, up to isomorphisms.  That is, no two groups in your list should be isomorphic.   I understand the basic use of Cayley tables in the sense that they are used to see what the operation on two of the elements becomes.  One group that I know that would fit this would be $\mathbb Z_4$.  I'm not sure how to list all of them and if there is a way to know if it will be isomorphic or not.


Topology on cartesian product and product topology.

Let X and Y be sets.  Does it have every topology on cartesian product X$\times$Y must be product topology ?


Reinstalling Ubuntu without formatting partition - what folders are deleted?

When re-installing Ubuntu on a partition where an existing Ubuntu installation already exists, and not choosing to format the partition, the installer shows a warning message before it begins installing:  The file system on /dev/sda5 assigned to / has not been marked for formatting. Directories containing system files (/etc, /lib, /usr, /var, ...) that already exist under any defined mountpoint will be deleted during the install. Please ensure that you have backed up any critical data before installing.  The list of "system directories" here does not seem complete. Furthermore, I would expect /home to be a system directory, but from experience I know that /home is not erased. What is the complete list of directories that will be removed during install?


What units and structures in Starcraft can be repaired? Can allied units from other races be repaired?


How does sudo handle $HOME differently since 19.10?

In Ubuntu releases prior to Ubuntu 19.10 Eoan Ermine, when I run a command with sudo, that command receives my home directory in the $HOME environment variable. This is the behavior I have long expected and . If I want sudo to reset the $HOME environment variable, so that it refers to the target user's home directory instead of my own, I have to pass the -H option (or -i, though that does more).    ek@Kip:~$ lsb_release -d Description:    Ubuntu 18.04.3 LTS ek@Kip:~$ sudo printenv HOME  # Shows ek's home, not root's. /home/ek ek@Kip:~$ sudo -u as printenv HOME  # Shows ek's home, not as's. /home/ek ek@Kip:~$ sudo -H printenv HOME  # Shows root's home. /root ek@Kip:~$ sudo -Hu as printenv HOME  # Shows as's home. /home/as   When I first upgraded to Ubuntu 19.10, I was surprised to discover that sudo seems to reset $HOME no matter what! I continue to observe this now that 19.10 is released and I've installed updates--both on newly installed systems and one I upgraded to 19.10.  ek@Cord:~$ lsb_release -d Description:    Ubuntu 19.10 ek@Cord:~$ sudo printenv HOME  # Shows root's home, even without -H or -i. /root ek@Cord:~$ sudo -u as printenv HOME  # Shows as's home, even without -H or -i. /home/as ek@Cord:~$ sudo -H printenv HOME  # Also shows root's home. /root ek@Cord:~$ sudo -Hu as printenv HOME  # Also shows as's home. /home/as   I thought this might be due to .  But I checked, and always_set_home does not appear in any Defaults line in my 19.10 /etc/sudoers file.  What makes sudo treat $HOME differently starting in 19.10, and why was this change made? Does this make it safe to use plain sudo in cases where I would previously have used sudo -H?


Converting Esri Shapefile to Geojson file

I am trying to convert an Esri shapefile, e.g. wards boundary data, to a Geojson file format.


I would like to know whether or not a verb in its bare infinitive form can be used as the subject of a sentence.  In other words, is it grammatically correct to say:     Do what her/his mother asks is something a child has to learn.   I have checked a few grammar books and none mentions this use (if any). Still, it does not necessarily exclude the case.  Thanks.  [Added] If possible, I would appreciate it if a reference source can be provided to support your input. Many thanks for the discussion.


For what types of research designs should (Days|Subject) vs. (1|Days:Subject) random effect specification be used?

I am learning generalized linear mixed effects model, and today I realized that there are two ways to set random slope in lmer(), when dealing with data where same subjects are repeatedly measured.   fit1 <- lmer(Reaction ~ Days + (Days | Subject), sleepstudy) fit2 <- lmer(Reaction ~ Days + (1|Days:Subject), sleepstudy)   Looking at the results, it seems like lmer() doing different things. How each command differs from each other, and which should I use and when?  Update: Thanks to Matteo Lisi's answer and to the earlier post , I now understand the mechanism that the lme4 package is doing. However, I am still having difficulty understanding WHEN should I use WHICH. I would appreciate if you could explain for what types of research designs I should use which syntax.   Is that something I can choose based on AIC? Or, I should choose the syntax based on the design of the research? Could you provide examples of research designs?


The sum of an uncountable number of positive numbers

Claim: If $(x_\alpha)_{\alpha\in A}$ is a collection of real numbers $x_\alpha\in [0,\infty]$ such that $\sum_{\alpha\in A}x_\alpha<\infty$, then $x_\alpha=0$ for all but at most countably many $\alpha\in A$ ($A$ need not be countable).  Proof: Let $\sum_{\alpha\in A}x_\alpha=M<\infty$. Consider $S_n=\{\alpha\in A \mid x_\alpha>1/n\}$.  Then $M\geq\sum_{\alpha\in S_n}x_\alpha>\sum_{\alpha\in S_n}1/n=\frac{N}{n}$, where $N\in\mathbb{N}\cup\{\infty\}$ is the number of elements in $S_n$.  Thus $S_n$ has at most $Mn$ elements.   Hence $\{\alpha\in A \mid x_\alpha>0\}=\bigcup_{n\in\mathbb{N}}S_n$ is countable as the countable union of finite sets. $\square$  First, is my proof correct? Second, are there more concise/elegant proofs?


What is the difference between sigaction and signal?

I was about to add an extra signal handler to an app we have here and I noticed that the author had used sigaction() to set up the other signal handlers. I was going to use signal(). To follow convention I should use sigaction() but if I was writing from scratch, which should I choose?


Visit the UK with Schengen tourist short-stay visa

I'm Russian, and I have touristic  Schengen short stay visa. I want to know, can I stay for some period in UK without getting UK visa, or it is not possible (I heard about 36 hours free of visa staying or something like that)


How to change the purple background color in grub?

How to do this manually, not installing any tools?


Powering a load with specified maximum current of 300mA. Is it safe to use a matching voltage power supply with a higher current rating?

I just bought a guitar amp that can be powered by a 9v battery or a 9v power supply.  The instructions that came with the amp specify that the power supply should deliver 300mA maximum.  As far as I understand, the load determines how much current is drawn, so why would it be dangerous to use a power supply with say, 1A?  I don't want to fry the amp, but I also don't want to go track down a different supply.  Here's my guess.  I think it's probably not safe.  I noticed that when I turned the volume up while using a 9v battery, playing a note loudly would cause the amp to die for a moment, which I assume means it's trying to draw more current than the battery can supply.  This seems to imply that louder volume equals more current draw from the power source.  If I plug in a power supply with a current rating of higher than 300mA, there's the possibility that the amp will attempt to draw in more current than it can handle when playing loudly and fry itself.  Is this what's going on?


Can I develop ubuntu for phones apps in Python?

Does anyone know if we can develop apps for ubuntu for phones in Python ?  PyQT / PySide would seem to support also QML. But can we use them on the phones ?


List all tables that a specific login has permissions

This might be repetitive, but I haven't found a solution that serves my purpose 100%. What I'd like to achieve is to have a script (or SP) that'll list all tables that a user has permissions on. Any insight will be helpful.  PS: I'm not very good with TSQL. :(  Thanks a lot.


Prove $\lim_{x\rightarrow c} \sin x =\sin c$ using $\epsilon$-$\delta$ definition

Proof. $\forall \epsilon>0$, choose $\delta=\epsilon$. Now $\forall x$, if $0<|x-c|<\delta$, then $|\sin x -\sin c|=|2\cos\frac{x+c}{2} \sin\frac{x-c}{2}|\le 2|\sin \frac{x-c}{2}|\le 2|\frac{x-c}{2}|=|x-c|<\delta=\epsilon $, which completes the proof. The proof above uses $|\sin x|\le |x|$, which is easy to show geometrically. However, I am afraid it is not rigorous. Can anyone tell me how to show $|\sin x|\le |x|$ without using derivative or Taylor expansion? Thanks in advance.


It is possible to get tier demoted on season 5?

Is it possible to fall from Platinum to Gold and from Gold to Silver on season 5? Since in every season stuff like that change I would like to know. And if yes, how many games you need to lose in a row in order to get demoted?


Could you please describe how SQL Server 2014 do cardinality estimation of Join predicate?

I found the information about CE of single filter predicate, multiple filter predicated but I have not found anything about JOIN predicate.


Inequality involving $\limsup$ and $\liminf$: $ \liminf(a_{n+1}/a_n) \le \liminf((a_n)^{(1/n)}) \le \limsup((a_n)^{(1/n)}) \le \limsup(a_{n+1}/a_n)$

This may have been asked before, however I was unable to find any duplicate. This comes from  of "Mathematical Analysis: An Introduction" by Browder. Problem 14:     If $(a_n)$ is a sequence in $\mathbb R$ and $a_n > 0$ for every $n$. Then show:   $$ \liminf(a_{n+1}/a_n) \le \liminf((a_n)^{(1/n)}) \le \limsup((a_n)^{(1/n)}) \le \limsup(a_{n+1}/a_n)$$   The middle inequality is clear. However I am having a hard time showing the ones on the left and right. (It seems like the approach should be similar for each). This is homework, so it'd be great if someone could give me a hint to get started on at least one of the inequalities.  Thanks.


What is the command line statement for changing the System clock?

Is there such command for changing the System clock's date and time?  For example:  The current date and time is January 1, 1970 22:30:59:980 where 59 and 980 refers to the seconds and millisecods respectively  And I want to change it to January 2, 1971 23:31:59:990  Is there a command for this?


How to access the grub boot menu in order to generate bootchart?

I am running Ubuntu Gnome 15.04, and I want to generate a bootchart to help me diagnose some system problems. However in  it says:    So how do I access the grub boot menu in order to append this text? And just to be clear, how should the line look once I have appended the necessary text? Also, is grub already installed for I don't appear to have either or these packages: grub or grub2?    OS Information:  No LSB modules are available. Distributor ID: Ubuntu Description:    Ubuntu 15.04 Release:    15.04 Codename:   vivid


Is it normal to have 28.5% of various income taxes deducted from my paycheck?

I just got out of college, still live with the parents (saving up money) been employed for a year in the industry, and got a not bad starting salary. First check I received was shocking, to see 28.5% cut off for Federal + MA State + SS Employee. And this is prior to enrolling in the 401k.  Is that normal?


If $x,y,z \in \mathbb{R^+}$ such that $x+y+z=3$. Prove the inequality $\sqrt x+\sqrt y+\sqrt z\ge xy+yz+zx$.    My work: We have   $$3(x+y+z)=x^2+y^2+z^2+2(xy+yz+zx) \implies (xy+yz+zx)=\dfrac12(3x-x^2+3y-y^2+3z-z^2)$$  So, we have to prove, $\sqrt x+\sqrt y+\sqrt z-\dfrac12(3x-x^2+3y-y^2+3z-z^2)\ge 0$    Now, I cannot proceed further. Please help.


Tag links are broken on stackexchange.com

Search results on  may contain questions which have tags.         These tags are clickable, but .  Seems related to old one:


Clicking links in pdfs opened with Okular opens Abiword (instead of the default browser)

I work with Xubuntu 12.04 and use Okular (version 0.14.3) to view pdf files. If I click a web link in a pdf file (created with "pdflatex" using the "hyperref" package), "Abiword" (It's a word-processing software, like Libreoffice writer) is opened instead of my default browser google-chrome. How can I change this behavior? The settings in Okular do not seem to provide a solution.   (Note that I set google-chrome as the preferred application for web browsing under Settings -> Preferred Applications, so that's not the problem).


can't figure out where are Errors compilations in apa7 or apa6

I can't figure out where are the errors during the compilation in latex here is a sample with my preambule.      \documentclass[man]{apa7}     \usepackage[american]{babel}      \usepackage{amsfonts,amssymb,amsmath,amsthm,mathtools}     \usepackage{marvosym}     \usepackage{pifont}     \usepackage{fancybox,fancyhdr}     \usepackage{graphicx}     \usepackage{eso-pic}     \usepackage{booktabs,tabularx}     \usepackage[T1]{fontenc}     \usepackage[utf8]{inputenc}     \usepackage[dvips]{epsfig}     \usepackage{caption,subcaption}     \usepackage{algorithmicx}     \usepackage[ruled]{algorithm}     \usepackage{algpseudocode}     \usepackage{xcolor}     \usepackage{csquotes}     \usepackage[backend=biber,style=apa]{biblatex}     \usepackage[backend=biber,style=apa,sortcites=true,sorting=nyt]{biblatex}     \DeclareLanguageMapping{american}{american-apa}      \DeclarePairedDelimiter{\norm}{\lVert}{\rVert}     \DeclarePairedDelimiter{\abs}{\mid}{\mid}     \captionsetup{labelfont=bf,skip=0.5\baselineskip,justification=raggedright,singlelinecheck=false}     \usepackage{pdfsync}     \usepackage{hyperref}      \newtheorem{rem}{Remark}[section]     \newtheorem{defi}{Definition}[subsection]      \addbibresource{distbib.bib}       \title{Sample APA-Style Document Using the \textsf{apa7} Package}     \author{Daniel A. Weiss}     \affiliation{A University Somewhere}     \leftheader{Weiss}     \abstract{This demonstration paper uses the \textsf{apa7} \LaTeX\     class to format the document in compliance with the 7th Edition of     the American Psychological Assocation’s \textit{Publication Manual.}     The references are managed using \textsf{biblatex}.}     \keywords{APA style, demonstration}     \begin{document}     \maketitle     We begin with \textcite{Scha85}. We can also cite this work in     parenthesis, like this: \parencite{Lam1}.     A three-author paper \parencite[e.g.,][]{rao} lists all     three authors for the first citation, then only the first author     on all subsequent citations \parencite{rao}.     Note the use of five heading levels throughout this demonstration     Method section.     %\input{chap2}     \section{Method}     \subsection{Participants}     We had a lot of people in this study.     \subsection{Materials}     Several materials were used for this project. Some of them were     already created for prior research.     \subsubsection{Paper-and-Pencil Instrument}     We used an instrument that we found to be highly successful.     \paragraph{Reliability}     The reliability of this instrument is extraordinary.     \paragraph{Validity}     We now discuss the validity of our instrument.     \subparagraph{Face validity} The face validity is exceptionally     \section{Discussion}     This is a lengthy and erudite discussion. It demonstrates amazing     skill in interpreting the results for the masses.     \printbibliography     \end{document}


I want to ask a question whose meaning is "what is the exact way in which X works?". Where is the most appropriate place for the adverb "exactly"?   How exactly does X work? How does exactly X work? How does X exactly work? How does X work exactly?


I have Written all the code well but i dont know what is the erroe and how to slove it. While i run the programm the following error will occure


How to visualize multivariate linear regression?

When I have data which has one dependent and one independent variable, I can clearly explain it in cartesian coordinate system  here is a regression line when my $y$ approximately equals to $2x + 3$ but what about a second variable ? what if my model was $y = 2x + z +3 $ ? would visualizing it be only possible with a three-dimensional coordinate system ? if it is, what about four and more ? My question might be a bit pointless, thanks in advance.


Consider the following code example:  \setuppapersize[A8,landscape][A8,landscape] \starttext \startformula     \startalign         \NC 1 \NC= 1\NR         \NC 2 \NC= 1\NR         \NC 3 \NC= 1\NR         \NC 4 \NC= 1\NR         \NC 5 \NC= 1\NR         \NC 6 \NC= 1\NR         \NC 7 \NC= 1\NR         \NC 8 \NC= 1\NR     \stopalign \stopformula \stoptext   Coming from a LaTeX background I would expect align to break over pages and  tells me     Somewhere between March and Arpril, \startalign lost the ability to break equations across pages. Hopefully, it will be added back soon.   So basically it is intended to have page breaks, isn't it? Question: How to enable them for align?


I understand, that similar questions were already asked here, and I have tried some of suggested solutions (latex2rtf, converting output pdf to doc with different convertors), but didn't find one that works for me.     What are my circumstances: I work on Windows 8.1, in TexStudio, using TexLive. I use xelatex, because I need Times New Roman Cyrillic in output pdf. My text are mostly in Russian and English, don't contain equations, but contain illustrations and text fragments in Oldchurchslavonic and Greek. I use biblatex and biber for building bibliography.   Often I need to send documents in .doc format, because many journals in my knowledge area don't accept articles in .tex or .pdf. So LaTeX fits perfectly in my workflow except of the final stage.   I tried to use latex2rtf, but run into some encoding problems. What I did finally was converting pdf to doc with trial verstion of Nitro PDF and then spending about two hours cleaning the file from double spaces, hyphens turned into dashes, unexpected line breaks etc. It was definitely not the best solutoin, but I don't have time to search a different one.   Is there any solution for converting latex to .doc or .rtf that will work under described circumstances OR a pdf to doc converter that produces editable .doc?


Pass environment variables to .desktop file Exec entry

I want to create a shortcut that executes a program with an environment variable set, for example:  [Desktop Entry] Version=1.0 Name=Chromium test UTC Exec=TZ=UTC chromium-browser   The syntax above doesn't work (the shortcut is invalid) and I can't find anything about passing env vars in .  Is that just not possible and I need to create a launcher script?  Ubuntu 18.


Get browser popup blocker status using JavaScript

To end a user´s browsersession successfully on browser-unload we need to open a new window to call some webservice to reset the user´s session data on the server. With an active popup blocker this will not succeed.  Our solution is querying the popupblocker-status when starting our application, stop further execution when the blocker is turned on, and request the user to turn off popup-blocking, or at least make him/her accept popups from our application/url or not....  I have read a lot on how to determine if a popup is being blocked. All examples are using window.open which actually opens a window if the blocker appears to be off.  We would like to avoid this window to appear (and close it right away), just to check if the blocker is turned on.  Do you happen to know if there is an alternative way to get a browser´s popupblocker-status? By reading a browser-property for example?


How to tell Google my content will expire after a certain period?

Right now I'm facing issues with 404 (Not Found) errors, because my content will deleted automatically after two months. I cannot change this behavior, because it is a real estate web site and once it is rented or sold it needs to be deleted and also so many factors behind this.  So I want to tell search engines about the availability of my contents and don't return a 404 error.


Questions with once good answers that are now out of date and need updates

What is the endorsed way of requesting updated answers to an old question?  Say I'd like to know the best GUI application for some command line tool. Of course this question already exists and has an accepted answer dating of two years ago. Since then new applications have seen the light and are maybe also featured in some comments or answers, but I'm not sure that their votes have catched up because old questions don't get that much attention.  Should I just ask a new question pointing out that I consider the duplicate question stale?   There's another  where the answer suggests that the mechanism for keeping answers up to date is downvoting older and upvoting newer answers. I don't have the impression that this mechanism really works for all types of questions.


Do incoming wires to my bank account get reported to the IRS?

If I wire a large amount of money from an online exchange to my bank account, will it get reported to the IRS? The money is coming from a Crypto trading exchange. Edit: this question is not related to the 2013 loan question answered below.


Now that the tag editing privilege has been removed, tag edits go through the Suggested Edits queue.  The problem is that users are suggesting edits that are pure tag edits. I'm sure most are in good faith and not trying to game the system, but there are usually other problems with the post. The suggested action is to either reject as "Too Minor" or to improve the edit.  The problem is that I don't want to award the reputation when there are other problems with the post. I want the user to learn that minor edits are discouraged. However, sometimes, their tag edit is really good. So, I want to keep that tag edit, but I don't want to award the reputation. The only thing I can do is look for something else that can be changed (like removing a "Thanks"), fixing it, and unchecking the "Suggested Edit was helpful" box.  However, , that soon becomes a problem. Especially with users who click through to earn badges with no regards to quality!  I also feel that having an edit rejected due to my "improvement" can discourage users. That's not what we want! We want users to improve the site through editing!  We need a way to approve tag edits without discouraging users by rejecting. The only way to due this currently is to approve them. The flaw with that, as mentioned above, is that the user doesn't learn.  I propose we keep tag edits going through the queue, but either don't award reputation, or only award one rep point.  Who's with me?!


Why is the price between these two lens differ so much?

I am a beginner in photography and trying to understand about camera lenses. This morning I came across Mike Matas' video which was made using this thousand dollars .   I also have a 50mm lens for my , but it only cost me way less than his lens did. Other than the obvious maximum aperture difference, what makes their prices differ so much - and how does it will affect the quality of the pictures taken?


My question was marked as a duplicate of a question that involved a more obscure use case

The voting seems to suggest that my question helped promote the other question. I don't know if chronological precedence is a criterion. I wonder if it is fair that the votes my question might have continued to receive will now most probably be received only by that question, which hadn't got too many votes before I asked my question.  I'm asking out of curiosity. I am actually pleased with the way my question was handled. And it's not like I asked it for the votes anyway.


I try to type correct password. but it say "Sorry Try again" I try to type so long time. But nothing happen. Why?


In a group $G$, if $a^3=e$ for all $a$ belongs to $G$, then is $G$ abelian?

It's easy to show that $G$ is abelian if $a^2=e.$  Can't seem to figure out how to prove/disprove this.


Book about princess who travels to another planet to wed the prince who then is exiled

I can't remember the name of this novel. Non-traditional princess is sent across space by her father the king to marry the crown prince as a diplomatic move. There are priests and a type of angelic presences.  The princess set up sword-fighting lessons for the ladies of the court and scandalized everyone. The prince gets a disease that causes him to be exiled to a walled city where the diseased are sent to die.  There are factions among the exiled.  Princess eventually goes to the city. I think the prince was hiding his identity.  Eventually, there was a battle against the king's soldiers.    This was probably published 3 to 5 years ago.  I listened to the audio-book.  It seemed like it may have been the first of a series but I'm not positive.  My library had it classified as science fiction but it had a lot of fantasy elements.


Is there any Potterverse explanation for a wand?

Is there a reason in the Potterverse to use a wand?  There are many creatures that use magic without a wand, why do wizards need to use wands?


What is $[\mathbb{Q}(\sqrt [3] {2}+\sqrt {5}):\mathbb{Q}]$? A straight forward way will be to just set $x=\sqrt [3] {2}+\sqrt {5}$, take powers and reach at a polynomial in $x$ and show the polynomial is irreducible. But the method is very tedious and seems to be hopeless. Any idea?


Is it safe to unplug a iPad or iPhone without ejecting first?

Should I eject the device first? Or can I just unplug my iPad or iPhone when I am done charging.


I'm trying to graph the function $y = \frac{x^2-4}{x-2}$.  I factored the numerator into $(x+2)(x-2)$, and then canceled the common factor (x-2), leaving the function as $y = x + 2$.    Is it acceptable to graph the original function as $y = x + 2$, a straight line with domain and range all real numbers?  Or do you have to restrict the domain as in the original function?  Thanks, Sean


Trying to run a JFrame with BorderLayout but the program is having a run-time error. java.lang.NullPointerException pops up

import java.util.ArrayList; import javax.swing.*; import java.awt.*; import java.io.*;  public class Login  {     private JFrame theWind;     //private JPanel thePane;     private JLabel title;     private JButton ok;     //private JButton cancel;     private JTextField theText;      public Login(){     }      public void open(){         theWind = new JFrame("Login");         title = new JLabel("Please Enter Your Voter ID:");         ok = new JButton("OK");         //cancel = new JButton("Cancel");         theText = new JTextField();         theWind.setLayout(new BorderLayout());         theWind.add(title,BorderLayout.NORTH);         theWind.add(theText,BorderLayout.CENTER);         theWind.add(ok,BorderLayout.SOUTH);          theWind.pack();          theWind.setVisible(true);     } }   I apologize this isn't the complete programs so some of the variables are not used yet. So when i click a button on another JFrame, this JFrame is supposed to open up. The problem occurs when it hits the line that sets the value for the Jframe. (the code below).  theWind = new JFrame("Login");   I get a run time error claiming a  NullPointerException on that line. I checked to see if the the JFrame was declared, and it is.  This is weird considering that my other JFrame runs fine, and I have all of the necessary java libraries imported. I have a JPanel and a JButton commented because I was trying to figure out if those things were messing up with the borderlayout but I don't think that's the problem. It's a relatively short code and I'm really stumped on this. I would be glad to receive any inputs/advice. thank you!


Why does the surface of a lake suddenly change texture

What causes the surface of a lake to suddenly change texture. More specifically, what causes short wavelength water waves to dissipate in certain regions of a body of water with fairly sharp transition between regions with short wavelength waves and those without?     I took a kayak out on lake Michigan (not pictured) and paddled out to a line of transition between water textures. I was about 0.5km from the shore in water much deeper than the wavelength of the surface waves (>2m; longer than my paddle).  The air was still, with almost no detectable wind. The water was clear, and I could see at at down to at least the length of my paddle (2m), and there were visibly no fish in the water.  To my left the water was rough, with both short wavelength waves (1-5cm) and long wavelength waves (20cm - 1m). To my right, there water was smooth with no visible short wavelength waves but the same long wavelength waves. The transition between the two regions was about 4 meters wide, and both the smooth and rough regions cover very large areas with apparently consistent wave texture within them. It's as if something was low-pass filtering the waves, and I have no idea what it could be. What causes that?   (Neither the smooth nor the rough region featured speckled interference waves like those here: )  Here's some stock photo of the effect:


When am I notified of edits on my posts?

I know that I'm always notified of suggested edits on my post, I also remember being notified of an edit on my answer by a 2ker and other times, but I don't know which are the triggers of the later. Other than suggested edits, what are the conditions to be notified of edits made by people with editing privileges?


Blockquotes should be formatted to support bullet points and numbered lists

I was proposing an idea on a , and I noticed that you cannot use bullet points inside a blockquote. To show what I mean, here are some images:  Part of the original post I was trying to quote   My post on MA.meta   Notice that the bullet points are outside the blockquote. This is frustrating, because I don't want to have to change the quote at all, then it's not really a quote. Should blockquotes have closing tags as well or have a different markup symbol? Even when I use

 bullet points aren't recognized; they turn out like this:   This is an issue, because   A. It looks bad  B. It's technically not a quote anymore  C. It takes away the entire emphatic purpose of bullet points in the first place


I was wondering if there's a nice general solution for the following problem:  How many numbers in the $n^\text{th}$ row of Pascal's triangle are even? How many are odd?


How can I print lines containing 3 words

I would like to print lines in my file which containing 3 words seperated my 2 spaces.  for example:   AAA BBB CCC BB AA CCCCCCCC   only AAA BBB CCC sshould be printed.  I already use grep for it but I cant handle the spaces.


What is the word, a noun or an adjective that describes majority of comments, on an article for example, as “useless” compared to just one brilliant comment. “Useless” comments are dull, idiotic, stupid, ignorant, nonsense,  etc. The word Garbage would be accurate, but it is insulting. The word should not insult anyone. The point of that word is to emphasize the opposing brilliance of one comment compared to 100 of others.   Example sentence:  "Most of these comments are ________, but a few are brilliant."


How to quickly search and navigate to the particular sub directory?

I often find myself in the situation where the directory structure is like:  a/b/c/d/f/g/...  and I am at a as pwd and wish to quickly navigate to f or g.  Is it possible to search and move to the particular directory from a as my pwd?


Calculate the area covered by a pixel in Google Earth Engine?

I am doing a project on calculating the growth of urban areas in different cities located in different parts of India.   I have been able to classify the area into urban, vegetation and water.   I cannot calculate the area covered by each pixel. I searched on Google and the available methods use band values, what I need is to find the area covered by urban/water/vegetation based on spectral end-member values that are been defined.   If anyone has the idea on how to perform it please share and if possible suggest an idea to export it into a graph.  Here is a link to the script:    EDIT: my aim to find the growth of an urban area or loss of vegetation in a region over the years. The urban area is indicated in red colour when you run the script.   I am finding how much area is covered by urban area so that I could measure the growth of the region.   I'm fairly new to Earth Engine.


What will be the equation of a wave on a string?

I have simple but a frustating doubt. I have seen that equation of a wave on a string can be given by $y=Asin(wt-Kx)$ or by $y=Asin(Kx-wt)$, where $w$ represents angular velocity of wave, $A$ represents amplitude, $K$ ($K=\frac{2\pi}{\lambda}$) represents wave number and $x$ represents displacement of wave at any time $t$. I was confused when I saw a sentence "Let's take a equation of a wave as $y=Asin(wt-Kx)$" in my textbook and a another statement "Let's take a wave equation as $y=Asin(Kx-wt)$" in another book. But how can both these different equation represents a wave tavelling in the same direction?. Because one of the wave equation represents wave travelling in $+ve$ y-axis and another represents the wave travelling in $-ve$ y-axis, from mean position at $t=0$  Being simple I would just ask that, If I am asked to write a wave equation which is traveling with a angular velocity $w$, with some amplitude $A$ starting from mean position at $t=0$ what would be my answer? Is it be  $y=Asin(wt-Kx)$ OR $y=Asin(Kx-wt)$? I get much confused while dealing with word problem questions as using these two equation gives two different answers. So I don't know which one to use when.


I'm new to this, so wondering if someone could please advise why isNaN() is undefined? package nan;  public class nan {      public static void main(String[] args) {                 {            if (isNaN(1))            {System.out.println("true");}             };      } }  thanks


How to avoid "unchecked or unsafe operations" warning in case of generic method

I would like to avoid "unchecked or unsafe operations" message from java compiler, but I have no idea how to do it, when I have a generic method, and would like to return the values from a generic Map. The Map's values should be the same generic type as the generic method, but I couldn't figure it out how to achieve.  I've created a bitbucket project to show the problem:   You can check the following snippet as a quick overview, but the best to clone the project and check it there.  public class VehicleServiceImplementation implements VehicleService {  private static Map<Long, VehicleResult> resultMap = new HashMap<Long, VehicleResult>();  static {     resultMap.put(5L, new VehicleResult<Car>(new Car(5L))); }  public <CAR extends Car> VehicleResult<CAR> retrieve(final CarRequest request) {     return resultMap.get(request.getId()); }}   Please note that I have no access to the interface itself, so I can't change it's signature  Please note that it's not about how to deal with Object returning methods, but about how to deal with generic methods.


Does the accepted sample based on the acceptance-rejection algorithm has the same distribution as X~$f(x)$?

In Bayes Statistics, does the accepted sample based on the acceptance-rejection algorithm has the same distribution as X~$f(x)$? Intuitionally it does, but how to prove it under the discrete and continuous cases respectively?


Adding ArcGIS Online Services to QGIS using MAC OSX?

I just read , but I do not have the options mentioned.     These are my options under Add Layer... Can't seem to find Add ArcGIS Map Server Layer. I'm running 2.18 on a Mac. There must be a difference between mac and pc versions? Is there a way to add ArcGIS Map Server Layer on a Mac??


Why do the temporal police of the 29th century Federation not correct the timeline when Spock creates an alternate reality?

Why do the "temporal police" from the 29th century that appeared in Voyager (USS Relativity and all that) not correct the timeline when Spock creates a black hole with Red Matter and gets sucked back to the 23rd century? You'd think that they would somehow attempt to eliminate the accidental alternate timeline... I would love an in-universe answer to this question.


I'm in need of a new desktop machine for both work and play. I'll be running a few VBox instances at once and would like to have multiple monitors connected to this machine to support these instances. The goal is to have 4 monitors so I can run these instances and view them at the same time (still need the money for this but it is my goal hahaha). Rather then just tossing money around and hoping I'd like to start doing some research now on hardware. Where should I look to get a good idea which items are compatible with Ubuntu and fully support the OS? In the past I was building more for Windows and would run Ubuntu in an image but now I an finally be done with Windows and really want to build this machine solely for Ubuntu :)


Can good letter of recommendations offset bad GRE scores?

I'm applying to graduate math programs and my subject test score was abysmal, but I'm very confident that I will have excellent letters of recommendation from my professors. Will these LOR offset the bad test scores? I know every situation is different, but in general what is your opinion?


In the terminal I get Command not found when I type:  airmon-ng start wlan0   What can I do to access the airmon-ng command?


Difference btw "Meanwhile", "in the meanwhile", "meantime", "in the meantime"

I've gone through the dictionary definitions but I'm honestly still confused. Is there any distinction at all between them? Can someone please use an example to explain the four words and how they differ, if they do differ?


How can I show only the current directory after the prompt in Ubuntu 10.04

I have tried the suggestions here:    But adding these lines to the .bashrc file had no effect.   Uname -a :  #46-Ubuntu SMP Wed Mar 7 13:47:05 UTC 2012 x86_64 GNU/Linux


I am using Ubuntu 17.10 with Wayland. It is detecting my Wacom tablet and I can use it for free painting, but the pen does not take over the main cursor, so I can see 2 cursors.  Seeing them would not be an issue, but if I want to paint straight line in MyPaint for example, it automatically takes the second cursor as start of the line, which makes it impossible to paint straight lines.  Is there a way to disable the second cursor and have only one when I use the pen?


Convert numeric string character to int32

If I have a string of digits and int variables a, b, c and I want to assign the first digit to int a, the second to int b and so on, how do I do that?  This snippet illustrates my problem:  var str = "123"; int a = Convert.ToInt32(str[0]); Console.WriteLine(str[0] + " " + a );   Output:  1 49   What do I do (besides subtract 48 from every attempted conversion)?  EDIT  Today I learned that str[0] produces a Char, not a string.


How to install bicycle pedals without a notch on the spindle?

I bought a pair of bicycle pedals that to my surprise had no notches on the pedal spindle to use when tightening them. I managed to screw them in by hand, but they are not quite tight since I can't use a spanner on them. So what would be the correct way to tighten them? Are there any special tools or similar that I'm supposed to use?  The offending pedals can be seen below. The spindle is, as you can see, completely smooth.


Impact on assigning value for variable with and without 'this' in javascript

function Myfunc() {     this.a = 10;     a = 20;     alert(this.a);     alert(a); }   Myfunc();   O/P: 20,20  What is the differnce bw this.a = 10; and a = 20; in the above code?


Which sites currently have review-audits?

Some sites have , and some don't. Which ones currently do and what is the criteria for activating this feature?


Taking a passport photo with DSLR Canon 1200D

New to this community. I have had a DSLR for a few years now so familiar with a few settings.  I tried and failed to take a passport photo . The main issue I am facing is getting shadows around the ears and cheeks?  I am not using any special lights, just using standard flash that comes with the camera  Am I trying the impossible here? just looking for any DIY tricks :)


Advice on beginning self-learning physics from scratch

I am pursuing masters degree in computer applications. I have no formal Mathematics and Physics background but for masters degree entrance examination I have studied senior high school level Mathematics with some introductory college level Mathematics like multi-variable calculus, advance linear algebra etc but that was 2 years back.  In my personal opinion computer programming is a monotonous work which is making me bored and from past 2 years (after studying mathematics)and I have a strong urge to self learn Mathematics and Physics.  Maths is prerequisite for both computing especially advanced topics (Algorithms, Artificial Intelligence etc) and Physics so I have decided to cover these Mathematical topics first  1. Linear Algebra by using   2. Trigonometry by using   3. Coordinate Geometry (Need Recommendation for book to cover this topic)  4. Calculus (Confused which book to use Thomas' Calculus or Stewart's or some other)   And finally  as my first physics book  It will take a lot of time to cover all this therefore I don't want to make any mistake in selecting wrong text for a newB. Can you help me by recommending some good books which i can use with or instead of books mentioned above and a suitable strategy to attain the goal in parallel with my regular studies.


My current tube was badly pierced by a screw in the street, so I wanted to replace it with a new one. The tire is a Continental 32 - 622 (28 x 15/8 x 1 1/4 - 700 x 32c), so I bought a 28" tube, exactly . (Actually I said in the shop that my tire was a 700 x 32c and they gave me the 28", which made sense at the point).  Then, when I put it in the wheel, it was obviously too long (excess length). How comes? Shouldn't a 28" tube fit perfectly a 28" tire? I got a 26" tube and it fits better. I'm very confused.  PS: The pierced tube was also too long, as it was folded. It's a second hand bike and it's the first time I've taken the tube out in 4 months.


Can we use HYPERLINK FORMULA field in salesforce 1?

I have created a HYPERLINK formula   HYPERLINK("/apex/my_VF_Page?Id="+ Id , "MY VF Page" )   If I use link in saleforce 1 App.  This link doesn't work any workaround so I add any logic in HYPERLINK for redirect to VF page in saleforce 1App.  Any Idea if we can use sforce.one.navigateToURL or something  javascript:sforce.one.navigateToURL('/apex/SimpleSiteProgram?id='+Id)


Debugging LaTeX Errors: how to isolate the problem

Using TeXWorks and TeXLive, usually errors display the relevant text, and I can go find the problem.  Of course, it would be nice if there were a button I could click to go there, but it's not crippling.  However, I now have a large document, and suddenly, I get the following error, with no clue about where in the document it is failing:  (c:/bin/texlive/2013/texmf-dist/tex/latex/hyperref/hyperref.sty (c:/bin/texlive/2013/texmf-dist/tex/generic/oberdiek/hobsub-hyperref.sty (c:/bin/texlive/2013/texmf-dist/tex/generic/oberdiek/hobsub-generic.sty)) (c:/bin/texlive/2013/texmf-dist/tex/latex/oberdiek/auxhook.sty) (c:/bin/texlive/2013/texmf-dist/tex/latex/hyperref/pd1enc.def) (c:/bin/texlive/2013/texmf-dist/tex/latex/latexconfig/hyperref.cfg) (c:/bin/texlive/2013/texmf-dist/tex/latex/url/url.sty))  Package hyperref Message: Driver (autodetected): hpdftex.  (c:/bin/texlive/2013/texmf-dist/tex/latex/hyperref/hpdftex.def (c:/bin/texlive/2013/texmf-dist/tex/latex/oberdiek/rerunfilecheck.sty)) (c:/bin/texlive/2013/texmf-dist/tex/latex/geometry/geometry.sty) (c:/bin/texlive/2013/texmf-dist/tex/latex/listings/lstlang1.sty)  (./QuickFlippedLessons2.aux ! Undefined control sequence. l.75 \@writefil  ?    I don't have a previous version saved, so finding this could be an extremely tedious process of deleting sections until I find the relevant one.  Is there anything I can do?


I want to install Firefox browser on my Mac laptop. I go to the Firefox website from Google and click on download. It downloaded a Firefox 77.0.1.dmg file. How do I install Firefox using this file? This does not look like Firefox icon.


How to do I save a file that has been put into the clipboard?

I'm using a program that exports an image to the clipboard. If I goto Finder->Edit->"Show Clipboard" a windows pops up showing the image.  How do I save this image to the Finder?  If I goto the Finder->Edit-> "paste" is greyed out.  Things I've tried:   pbpaste doesn't seem to see the image but the man page seems to insinuate that it only understands Encapsulated  PostScript  (EPS) .ps files New from Clipboard in SnagIt works but I'm guessing that it creates a new file and I'd like to get the original file. Paste into PowerPoint puts the file there...but I can't seem to take it out of there.  IE, dragging the image from PowerPoint to Finder doesn't work.


Requires installation of untrusted packages?

I tried installing VLC Player yesterday, and I got the Requires installation of untrusted packages error.  I searched for hours for a solution to this problem, and finally came upon a suggestion that said to change servers for downloading updates from.  I did this, and it gave me a 404 error when I clicked on "Check" in the Update Manager.  I tried switching my server back to the main one (and after that, several other ones), but I am now still getting a 404 error:   And the other error I get when downloading or updating:   Edit: Output of cat /etc/apt/sources.list:  deb-src http://us.archive.ubuntu.com/ubuntu/ precise main restricted #Added by software-properties  # See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to # newer versions of the distribution. deb http://us.archive.ubuntu.com/ubuntu/ precise main restricted multiverse deb-src http://us.archive.ubuntu.com/ubuntu/ precise multiverse universe #Added by software-properties  ## Major bug fix updates produced after the final release of the ## distribution. deb http://us.archive.ubuntu.com/ubuntu/ precise-updates main restricted multiverse deb-src http://us.archive.ubuntu.com/ubuntu/ precise-updates restricted main multiverse universe #Added by software-properties  ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team. Also, please note that software in universe WILL NOT receive any ## review or updates from the Ubuntu security team. deb http://us.archive.ubuntu.com/ubuntu/ precise universe deb http://us.archive.ubuntu.com/ubuntu/ precise-updates universe  ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu  ## team, and may not be under a free licence. Please satisfy yourself as to  ## your rights to use the software. Also, please note that software in  ## multiverse WILL NOT receive any review or updates from the Ubuntu ## security team.  ## N.B. software from this repository may not have been tested as ## extensively as that contained in the main release, although it includes ## newer versions of some applications which may provide useful features. ## Also, please note that software in backports WILL NOT receive any review ## or updates from the Ubuntu security team. deb http://us.archive.ubuntu.com/ubuntu/ precise-backports main restricted universe multiverse deb-src http://us.archive.ubuntu.com/ubuntu/ precise-backports main restricted universe multiverse #Added by software-properties  deb http://us.archive.ubuntu.com/ubuntu/ precise-security main restricted multiverse deb-src http://us.archive.ubuntu.com/ubuntu/ precise-security restricted main multiverse universe #Added by software-properties deb http://us.archive.ubuntu.com/ubuntu/ precise-security universe  ## Uncomment the following two lines to add software from Canonical's ## 'partner' repository. ## This software is not part of Ubuntu, but is offered by Canonical and the ## respective vendors as a service to Ubuntu users. deb http://archive.canonical.com/ubuntu precise partner deb-src http://archive.canonical.com/ubuntu precise partner  ## This software is not part of Ubuntu, but is offered by third-party ## developers who want to ship their latest software.


Transforming the dummy values to be able to take logs

I have a panel data model with double-log functional form. I have 4 variables, one of which is a dummy. What is the best way to transform the values of 0 for my dummy to be able to take natural logs (since you can't take logs from zero)? I have found 2 options so far, but I dont know which is the best (or perhaps there is a 3rd option).  1) Transform all the values of 0 into a very small value (0.00000000001) and then take the logs. I'm not sure this wouldn't still change the outcome of my model quite a bit. 2) Change the values of 0 into 1 and the dummy values of 1 into e (the base of natural logarithm). The log of this newly defined dummy then takes on the values of zero and one and the interpretation of my betas would remain the same.


How to write method that return an object pointer, function is declared in another header

I want to write a class like this. How can I define findMin and findMax function in another cpp file?  template <typename Comparable> class BinarySearchTree { private:     struct BinaryNode     {         Comparable element;         BinaryNode *left;         BinaryNode *right;          BinaryNode(const Comparable & theElement, BinaryNode *lt, BinaryNode *rt)         : element(theElement), left(lt), right(rt){}     };      BinaryNode * findMin(BinaryNode *t) const;     BinaryNode * findMax(BinaryNode *t) const; }


My problem is that when im trying to create a circle on a surface with loop tools' circle tool i end up with tis deformation.  To create the circle i subdivide the surface, delete the inner faces that i dont need and select the loop thats going to be my circle. Then i hit the circle tool and the deformation appears. If i create a seperate object no matter the "scales" or any transformation i apply to it the prosess above will be successfull. Clearly i am missing something but i cant find it. Thanks for your time.  ps. im relatively new to blender so anything at all would help


Exception when using CompareTo with a generic Bag of objects

I'm trying to implement a generic Bag class which, can count the number of Objects in the bag greater than object x, for this I'm using a Date class to test it.  Bag code:  class Bag<T extends Comparable<T>>  {// generic class with T standing for a class  private T[] bag = (T[])(new Object[100]);                  private int numElements = 0; // junk in bag[numElements..]   void add(T x)  { // put x in bag         bag[numElements] = x; numElements++; }  int freq(T x)  { // how many x’s in bag?         int count = 0;         for (int i=0; i<numElements; i++)             if (bag[i].equals(x)) // .equals because T a class                  count++;         return count; }  int numGreater(T x) {//number of objects greater than x      int greaterThan = 0;     for(int i = 0; i<= bag.length; i++)     {         if(bag[i].compareTo(x) == 1)         {             greaterThan++;         }     }     return greaterThan; } }   Date code:  import java.util.*; import java.lang.*;  class Date implements Comparable<Date>   { // dates  private int day, month, year;  Date(int day0, int month0, int year0)  {     day = day0; month = month0; year = year0; }  public String toString()  {     return "" + day + "/" + month + "/" + year; }  private int elapsedDays()  {     // Number of days elapsed from 1/1/1900 to this date     int days = (year-1900)*365+(year-1901)/4;      int k = 1;     while (k<month)      {         int daysInMonth;     if (k==9||k==4||k==6||k==11)daysInMonth = 30;         else if (k==2)          {             if (year%4==0 && year!=1900) daysInMonth = 29;             else daysInMonth = 28;         }         else daysInMonth = 31;         days = days + daysInMonth;          k++;      }     return days + day;     }      public int compareTo(Date d)     {         if(d.elapsedDays() > elapsedDays())         {             return -1;         }         if(d.elapsedDays() == elapsedDays())         {             return 0;         }         return 1;     }    }   and finally the test program i'm using:  import java.util.*; import java.lang.*;  class BagTest { public static void main(String[] args)  {//finds dates greater than today     Bag<Date> ds = new Bag<>();     Date today = new Date(07,11,2013);     Date d1 = new Date(1,11,2013);     Date d2 = new Date(8,11,2013);     Date d3 = new Date(9,11,2013);      ds.add(today);     ds.add(d1);     ds.add(d2);     ds.add(d3);      System.out.print(ds.numGreater(today)); } }   The error message i'm receiving is as follows:  Exception in thread "main" java.lang.ClassCastException: [Ljava.lang.Object; can not be cast to [Ljava.lang.Comparable;         at Bag.<init>(Bag.java:6)         at BagTest.main(BagTest.java:8)   Thanks in advance for any help!


"It had now been two weeks since he had left the house"

It had now been two weeks since he had left the house.   Is this use of since correct? Is the tense of the verb after it correct?


After the DEM creation, I wanted to create slope layer.   However, the result has not satisfied me. I don't think the slope map is correct. Have you ever encountered false calculated terrain map?  This is the DEM:    And this is the slope layer.


WMD/Prettify does not support dot character for XML elements

The WMD (or possibly Prettify)  does not support the dot (.) character for elements, despite it being part of the . This comes up on StackOverflow with XAML related questions.  Below is an example of the rendering of an element and attribute, both with a "." in their name. Notice that ".suffix" is coloured incorrectly.  <prefix.suffix />   (As a new user on this site I cannot mark this question as 'xml' or 'xaml', as was my intention)


regular expression allowing only english alphanumeric and "-"

I need a regular expression that allows english alphabets and numbers and "-" and not allow every thing else.  but recently I found out that my regular expression not stopping french language alphabets and numbers  My regular expression is as follow,  @"[^\w\d-]";   How can I change the above regular expression so only english alphabets, numbers and "-" can be allowed only?


What white point temperature should I set my LCD monitor to?

I've got the Xrite Eye One Display 2, and tried the advanced calibration today for the first time.  It asked what white point I wanted, and had a default of 6500K.  I didn't realize that was up for discussion!  I would have assumed the daylight temperature, around 5500K, would be desired.  What temperature do I want my whites to be? Why can't white just be white?!


I bought some prime trimmed beef brisket on March 9 with a sell by date of Mar. 12. It was kept in the frig in its foam/plastic wrap container until Mar.16. There was some odor when I opened it up and put it up to my nose. I washed it off and cut away some meat and scraped it off. Not much odor anymore. It had reached room temp for a short period of time before I did this and then I wrapped it and froze it.  Is it likely safe to eat? No children or immune compromised people will eat it and it will be thoroughly cooked first.


I don't understand this one part in the proof for convergent sequences are bounded.  Proof: Let $s_n$ be a convergent sequence, and let $\lim s_n = s$. Then taking $\epsilon = 1$ we have: $n > N \implies |s_n - s| < 1$ From the triangle inequality we see that: $ n > N \implies|s_n| - |s| < 1 \iff |s_n| < |s| + 1$. Define $M= \max\{|s|+1, |s_1|, |s_2|, ..., |s_N|\}$. Then we have $|s_n| \leq M$ for all $n \in N$.  I do not understand the defining $M$ part. Why not just take $|s| + 1$ as the bound, since for $n > N \implies |s_n| < |s| + 1$?


I refer to   which seems to question the importance of the normal distribution of the residuals, arguing that this together with heteroskedasticity could potentially be avoided by using robust standard errors.  I have considered various transformations - roots, logs etc. - and all is proving useless in resolving completely the issue.  Here is a Q-Q plot of my residuals:    Data   Dependent variable: already with logarithmic transformation (fixes outlier issues and a problem with skewness in this data) Independent variables: age of firm, and a number of binary variables (indicators) (Later on I have some counts, for a separate regression as independent variables)   The iqr command (Hamilton) in Stata does not determine any severe outliers which rule out normality, but the graph below suggests otherwise and so does the Shapiro-Wilk test.


How to limit charging to a user defined limit?

My UleFone Armor 2 has a 4700mAh battery and I would like to limit the charging to 60% to reduce battery aging. The batteries in most of the phones are not user-replaceable and I am worried that a factory/service battery replacement might affect water resistance negatively.  How can I limit the charging to 60%? (But not limiting charging speed. I love fast charging.)  Lenovo ThinkPads have a built-in feature that does this, called “battery preservation mode”.


Find all functions $f:\mathbb{R^*}\to\mathbb{R^*}$ that satisfy $$f(x)f(\frac{1}{x})=1\hspace{1 em}\forall x\in\mathbb{R^*}$$  I only found that every function $f(x)=x^n, n\in\mathbb{N^*}$ is a solution. Can you find all the solutions to this?