Show that $\mathbb{E}(T) = \sum\limits^\infty_{k=1}\mathbb{P}(T \geq k)$ for $T$ nonnegative integer valued and $E[T] < \infty$

Let T be a non-negative integer-valued random variable with $\mathbb{E}(T) < \infty $. Prove that $\mathbb{E}(T) = \sum^\infty_{k=1}\mathbb{P}(T \geq k)$.  Had a few attempts, haven't really got anywhere. I'm wondering as I'm typing this if proof by induction is a good way to go.  Edit: One major thing I forgot to add, am I correct in thinking that also, $\mathbb{E}(T) = \sum^\infty_{k=1}k\mathbb{P}(T = k)$?


Does punishment from god contradict the idea of free will?

In various religions it is often preached that god has given humans free will. But at the same time those religions preach that there is punishment for sinning.  Assuming a god does exist, and god does punish people for sinning, doesn't that contradict the idea of free will because if humans know they will be punished by god for sinning, it might stop them from doing the action in the first place?


I'm trying to generate unique purchase order numbers that start at 1 and increment by 1. I have a PONumber table created using this script:  CREATE TABLE [dbo].[PONumbers] (   [PONumberPK] [int] IDENTITY(1,1) NOT NULL,   [NewPONo] [bit] NOT NULL,   [DateInserted] [datetime] NOT NULL DEFAULT GETDATE(),   CONSTRAINT [PONumbersPK] PRIMARY KEY CLUSTERED ([PONumberPK] ASC)     );   And a stored procedure created using this script:  CREATE PROCEDURE [dbo].[GetPONumber]  AS BEGIN     SET NOCOUNT ON;      INSERT INTO [dbo].[PONumbers]([NewPONo]) VALUES(1);     SELECT SCOPE_IDENTITY() AS PONumber; END   At the time of creation, this works fine. When the stored procedure runs, it starts at the desired number and increments by 1.  The strange thing is that, if I shut down or hibernate my computer, then the next time the procedure runs, the sequence has advanced by almost 1000.   See results below:    You can see that the number jumped from 8 to 1002!   Why is this happening?  How do I ensure that numbers aren't skipped like that?  All I need is for SQL to generate numbers that are:   a) Guaranteed unique.  b) increment by the desired amount.    I admit I'm not a SQL expert. Do I misunderstand what SCOPE_IDENTITY() does?  Should I be using a different approach? I looked into sequences in SQL 2012+, but Microsoft says that they are not guaranteed to be unique by default.


Should you tune 'ntree' in the Random Forest algorithm?

In the original paper, I was under the impression that the RF couldn't really overfit.  However, in practice I'm seeing that increasing 'ntree' sometimes increases test set error. Is this due to randomness, or is there an optimal level for 'ntree'? Right now, I'm only using cross-validation to choose the optimal 'mtry'.  I am using R and the randomForest package implementation.


Android App Missing Delete Functionality?

Is the Android app missing the feature to delete your own posting, or am I missing it?  I've seen  and agree with it but that is about voting to delete, I'm talking about deleting ones own answers/questions.  I also tried to post a comment stating I was going to delete the answer I made but that also failed to post.


I would like to create a pdf file that containes only the table captions, but not the content of the table. So I tried to redefine the tabular environment in the preamble of my document (it is probably not the best solution but I don't mind quick and dirty - I need to use it only temporarily):  \let\oldtabular\tabular \let\endoldtabular\endtabular \renewenvironment{tabular}{\iffalse\oldtabular}{\endoldtabular\fi}   or  \usepackage{etoolbox} \preto\tabular{\iffalse} \appto\tabular{\fi}   Unfortunatelly, it seems to have no effect on my document. If I manually frame the tabular environment it works:  \begin{table}[htbp]     \centering     \caption{my captiontext}     \iffalse         \begin{tabular}             Content I don't want to see         \end{tabular}     \fi     \label{myTableLabel} \end{table}   Thanks in advance for any input!


Find all $f  \in \mathscr{C^\infty}(\mathbb R)$ that satisfy the equation   $$f'(x) = f(x+1) - f(x).$$   The 'obvious' answer is the set of all affine maps, but I'm not entirely sure.  Some progress:  For any $x \in \mathbb{R}$, we have $$f(x+h) = f(x) + f'(x)h + r(x,h),$$ where $r(x,h) = o(h)$. Letting $h = 1$, $$f(x+1) = f(x) + (f(x+1) - f(x)) + r(x,1).$$ This implies $r(x,1) = 0$ for all $x$, so the linear approximation is exact for an increment of 1.  I thought of Taylor's theorem as well. For any $x \in \mathbb R$, $$f(x+h) = f(x) + f'(x)h + \frac{f''(c)}{2}h^2$$ for some $c \in (x,x+h)$. Again letting $h = 1$ we get that $f''(c) = 0$, but that only shows that the second derivative vanishes at some point, not all points.  I have a feeling that the first proof just needs one extra step to finish the job. This problem is not for a class, so I would be interested in seeing the solutions if the $\mathscr{C}^\infty$ condition were weakened (my first proof only requires differentiability, so I would assume a proof requiring $\mathscr{C}^1$ would be on a different route).


I am from Turkey and I am married to a Spanish woman. We live in Spain and I have Family Resident Card issued by the Spanish authorities. We are going to the  UK for a 4-day trip. I applied for an EEA family permit but was told that it can take more than 4 weeks to be issued. Our trip is in 20 days.  My wife said that, if I don't receive before we leave, we can go to the airport, taking our marriage document with the official translation, and try to travel without the visa. She believes that I have the right to travel with her anywhere in the EU and they can't refuse me entry.    Is this accurate or is it a big risk? She claims that I could be stopped at the border, but they have to let me enter after questioning me.


While rewatching Star Wars my skin was crawling while watching Luke practice saber technique against a remote on the Falcon.  There's no way I'd want to be in the same room with a beginner waving a lightsaber around, let alone a beginner with his eyes covered.  Samurai apparently practiced with  to reduce training injuries.  Do lightsabers have lower power settings so that a wrong move while practicing doesn't sever a limb or chop through the hull into vacuum?


How to read a single character from the user?

Is there a way of reading one single character from the user input? For instance, they press one key at the terminal and it is returned (sort of like getch()). I know there's a function in Windows for it, but I'd like something that is cross-platform.


Import a shapefile to postgis with ogr2ogr gives: Unable to open datasource

I want to use ogr2ogr in order to import a shapefile in a postgis database. I have successfully installed ogr2ogr and I run from the pgsql the following command:  ogr2ogr -f "PostgreSQL" PG:"host=localhost user=user_1 password=***** dbname=imports" world_boundaries.shp   What I get back is an error message:  Unable to open datasource `world_boundaries.shp' with the following drivers: --a list of drivers follows (ESRI Shape File etc.)   I have also tried to define the full path of the shapefile but I got the same message.  Also I tried to run the:  ogrinfo world_boundaries.shp   Same thing.    After fixing the issues with the permissions of the file I get the following error:    ERROR 1: AddGeometryColumn failed for layer world_boundaries, layer creation has failed.   ERROR 1: Terminating translation prematurely after failed   translation of layer world_boundaries (use -skipfailures to skip errors)   I also tried to import it through the GUI shp2pgsql and I get the following error:   ALTER TABLE "public"."" Failed in pgui_exec(): ERROR:  permission denied for relation spatial_ref_sys  CONTEXT:  SQL statement "SELECT SRID         FROM spatial_ref_sys WHERE SRID = new_srid" PL/pgSQL function addgeometrycolumn(character varying,character   varying,character varying,character varying,integer,character varying,integer,boolean) line 50 at SQL statement  SQL statement "SELECT AddGeometryColumn('',$1,$2,$3,$4,$5,$6,$7)"  PL/pgSQL function addgeometrycolumn(character varying,character  varying,character varying,integer,character varying,integer,boolean) line 5 at     SQL statement  Shapefile import failed.   The issue this time was that this database user didn't have sufficient permissions. This fixed it:  GRANT ALL ON TABLE spatial_ref_sys TO my_user_name;   Next error message is:    Warning 1: Geometry to be inserted is of type 3D Multi Polygon, whereas the layer geometry type is 3D Polygon.  Insertion is likely to fail  ERROR 1: INSERT command for new feature failed.  ERROR:  Geometry type (MultiPolygon) does not match column type (Polygon)   So it seems I need to use the parameter: -nlt MULTIPOLYGON But when I do so I get another error, which doesn't make any sense to me:  ERROR 1: PostgreSQL driver doesn't currently support database creation. Please create database with the `createdb' command. PostgreSQL driver failed to create PG:host=localhost user=my_user_name dbname=my_database password=password -nlt POLYGON   But it gets loaded using the shp2pgsql GUI.    Comment of @elrobis enabled this to finally work. Data loaded in db correctly!  ogr2ogr -f "PostgreSQL" PG:"host=localhost user=geonode dbname=geonode_imports password=geonode" -nlt GEOMETRY wld_bnd_adm0_gaul_2015.shp


How to detect Windows 64-bit platform with .NET?

In a  2.0 C# application I use the following code to detect the operating system platform:  string os_platform = System.Environment.OSVersion.Platform.ToString();   This returns "Win32NT". The problem is that it returns "Win32NT" even when running on Windows Vista 64-bit.  Is there any other method to know the correct platform (32 or 64 bit)?  Note that it should also detect 64 bit when run as a 32 bit application on Windows 64 bit.


I'm using PDF-XChange to view pdf's. I have one pdf that has lock on it:    And I can't copy text from it:    How to solve copy/paste problem?


Pass object of a class to a method of another class

I have a class Matrix which contains the class definition:  import java.util.Scanner;  public class Matrix {      private int[][] matrix;      //construct matrix with given number of rows and columns     public Matrix(int n, int m){         matrix = new int[n][m];     }      //input values into matrix     public void readMatrix(){         Scanner input = new Scanner(System.in);         for (int r = 0; r < matrix.length; r++){             for (int c = 0; c < matrix[r].length; c++){                 matrix[r][c] = input.nextInt();             }         }     }      //display values of matrix     public void displayMatrix(){         for (int r = 0; r < matrix.length; r++){             for (int c = 0; c < matrix[r].length; c++){                 System.out.print(matrix[r][c] + " ");             }             System.out.print("\n");         }     } }   and a class MatrixApp which contains the main:  import java.util.Scanner;  public class MatrixApp {      public static void main(String[] args) {         Matrix m1 = null; //create matrix m1         promptMatrix(m1); //ask for data for m1 from user         m1.displayMatrix(); //display m1     }      private static void promptMatrix(Matrix m) {         Scanner input = new Scanner(System.in);         int rows, columns;         //ask for number of rows         System.out.print("Enter the number of rows: ");         rows = input.nextInt();         //ask for number of columns         System.out.print("Enter the number of columns: ");         columns = input.nextInt();         //create matrix         m = new Matrix(rows, columns);         //ask for matrix data         System.out.println("Enter matrix: ");         m.readMatrix();     } }   I get the Null Pointer Exception error on m1.displayMatrix(). I guess that is because nothing has been stored in m1 although I have passed m1 to the method promptMatrix. Why is that and how can I solve that, please?


What is taking up all this space on my hardly-used tablet?

I have a tablet that I got about 2 years ago, but never opened it until recently (it was a package deal, and my laptop finally died).  When I booted it up, it went through a whole bunch of automatic updates, which makes sense.  It eventually ended up running Windows 10 (this may have been one of the automatic updates).  What doesn't make sense is that Windows Explorer shows less than 2GB of free space out of 28.5GB on my C drive.  This makes it virtually impossible to install any new software.  I tried running disk cleanup and removing all programs that I had no use for, but this hardly put a dent in the used space.  Visible folders show nothing unusual.  There is both a Windows package and a Windows10Upgrade package, but the latter doesn't seem to be taking up excessive space.  Other than that there's just the Program Files and Program Files (x86), Users, and a small number of my own files that don't take up much room.  My only guess is that all of the upgrades left some sort of garbage behind (maybe copies of earlier Windows versions or something?), but I can't figure out where it's being stored or how to get rid of it.


How to restrict SSH users to a predefined set of commands after login?

This is a idea for a security. Our employees shall have access to some commands on a linux server but not all. They shall e.g. have the possibility to access a log file (less logfile) or start different commands (shutdown.sh / run.sh).  Background information:  All employees access the server with the same user name: Our product runs with "normal" user permissions, no "installation" is needed. Just unzip it in your user dir and run it. We manage several servers where our application is "installed". On every machine there is a user johndoe. Our employees sometimes need access to the application on command line to access and check log files or to restart the application by hand. Only some people shall have full command line access.  We are using ppk authentication on the server.  It would be great if employee1 can only access the logfile and employee2 can also do X etc...  Solution: As a solution I'll use the command option as stated in the accepted answer. I'll make my own little shell script that will be the only file that can be executed for some employees. The script will offer several commands that can be executed, but no others. I'll use the following parameters in authorized_keys from as stated :  command="/bin/myscript.sh",no-port-forwarding,no-X11-forwarding,no-agent-forwarding,no-pty ssh-dss AAAAB3....o9M9qz4xqGCqGXoJw= user@host   This is enough security for us. Thanks, community!


How to reset an NPC's dialogue options to reset a quest in Skyrim?

So I got married a few months back to an inn keeper, Wilhelm, but wanted to re-marry someone different. So, like any adventurer, I killed him. Unfortunately, (a) his body is still in my house, on the floor and won't leave and (b) I can't seem to re-marry. I went back to the temple of Mara in Riften and talked to Maromal, but the dialogue that triggers the quest, (Love is in the Air, or something like that.) that allows you to be married, won't come back. I have an amulet of Mara, but no one has given me the interaction to pursue marriage. How do I either reset the quest so I can re-do it, or reset Maromal's dialogue so I can get the quest? Also, how can I get rid of Wilhelm's body? Thanks :)


What is the vertical spacing caused by the \intertext or \shortintertext command?

\documentclass[letterpaper,10pt]{article} \usepackage{amsmath} \usepackage{nccmath}  \begin{document}  \begin{align*} \intertext{what is the vertical spacing here?} \\[-30pt] 1+2 \\ =3 \end{align*} \end{document}   There is an automatic vertical gap that the \intertext command inserts. I would like to know how many pts that gap is to exactly get rid of it with the \\[...] command explicit since manually adjusting this height gives me the freedom I require. -30pts is close, but it appears no integer value works and the ams manual doesn't specify the exact spacing of the intertext command.


Did Kurama become a whole after the last war?

Did Kurama get his half from Minato and become a whole after the war? Thus, in Boruto, is Kurama composed of yin and yang already?


Finding GIS consultancy/project work (rather than jobs)?

The post  listed resources for finding a GIS job (as in a full-time or contract position).  What resources are available for finding GIS projects or consultancy work? eg:   a small project to integrate a map into an existing site; incorporate an address-search into a workflow; migrate legacy GIS code to a new format;   These are one-off tasks which require a GIS professional, but which don't entail a full-time position. How do you find the right people for the task, or find the task if you're the right person? All the online resources I've seen are aimed at "jobs".


Does the uncertainty principle for energy and time prove it is impossible to reach absolute zero?

I have long wondered why nobody seems to think that this form of the uncertainty principle proves it impossible to reach absolute zero.  I noticed that there is a proof suggesting it requires infinite time to reach absolute zero in :     "Here, we provide a derivation of the principle that applies to arbitrary cooling processes, even those exploiting the laws of quantum mechanics or involving an infinite-dimensional reservoir. We quantify the resources needed to cool a system to any temperature, and translate these resources into the minimal time or number of steps, by considering the notion of a thermal machine that obeys similar restrictions to universal computers. We generally find that the obtainable temperature can scale as an inverse power of the cooling time."   But they do not mention a connection to the uncertainty principle. Can anyone help?


How to show if $|a_{n+1} - a_{n}| \le \frac{1}{2^n}$ then the sequence is Cauchy.

Let $\{a_n\}$ be a sequence of real numbers such that $|a_{n+1} - a_n| \le \dfrac{1}{2^n}$.   I would like to show that this sequence is Cauchy.    Letting $\epsilon > 0$, I said choose $N$ such that $1/2^N \le \epsilon$. However, I'm not sure if this is the right $N$, since $m, n > N$ doesn't seem to necessarily imply $|a_n - a_m| \le \epsilon$.  Can someone show me the light?


Inability to view MathJax in Questions list in Android App

I use the Android app of SE to access the site. However, I cannot see any MathJax formatting in the questions list:    However, I can see clearly MathJax formatted text when I open a question.  Is this a bug, or the feature is missing? In any case, it should be corrected.  N.B.: I've used the example of Mathematics SE, but this is valid in any other site as well.


Normal random vector with some known values

I need help with some questions regarding the normal random vector. Suppose that I have a random vector that follows a multivariate normal distribution $$ \boldsymbol{X} = \begin{bmatrix} X_1 \\ X_2 \\ X_3 \end{bmatrix} \sim \mathcal{N}_3 \left( \begin{bmatrix} \mu_1 \\ \mu_2 \\ \mu_3 \end{bmatrix}, \begin{bmatrix} \sigma_{11} & \sigma_{12} & \sigma_{13} \\ \sigma_{21} & \sigma_{22} & \sigma_{23} \\ \sigma_{31} & \sigma_{32} & \sigma_{33} \end{bmatrix} \right) $$ Now, for some reason, I can observe $X_1 = x_1$. I know that the sub-vector $\begin{bmatrix} X_2 \\ X_3 \end{bmatrix} \sim \mathcal{N}_2 \left( \begin{bmatrix} \mu_2 \\ \mu_3 \end{bmatrix}, \begin{bmatrix}  \sigma_{22} & \sigma_{23} \\  \sigma_{32} & \sigma_{33} \end{bmatrix} \right)$, but I wonder if it is the case that $$ \boldsymbol{X} \ \mid X_1 = x_1 \quad \text{or} \quad \begin{bmatrix} x_1 \\ X_2 \\ X_3 \end{bmatrix} \sim \mathcal{N}_3 \left( \begin{bmatrix} x_1 \\ \mu_2 \\ \mu_3 \end{bmatrix}, \begin{bmatrix} 0 & 0 & 0 \\ 0 & \sigma_{22} & \sigma_{23} \\ 0 & \sigma_{32} & \sigma_{33} \end{bmatrix} \right) \quad ? $$ That would be my first question. Another question would be, with the same normal random vector $\boldsymbol{X}$, I know that any linear combination of the components of $\boldsymbol{X}$ is also normally distributed. Specifically, $$ a_1 X_1 + a_2 X_2 + a_3 X_3 \sim \mathcal{N}_1 \left( \begin{bmatrix} a_1 & a_2 & a_3 \end{bmatrix} \begin{bmatrix} \mu_1 \\ \mu_2 \\ \mu_3 \end{bmatrix}, \begin{bmatrix} a_1 & a_2 & a_3 \end{bmatrix} \begin{bmatrix} \sigma_{11} & \sigma_{12} & \sigma_{13} \\ \sigma_{21} & \sigma_{22} & \sigma_{23} \\ \sigma_{31} & \sigma_{32} & \sigma_{33} \end{bmatrix} \begin{bmatrix} a_1 \\ a_2 \\ a_3 \end{bmatrix}  \right) $$ Now, again, I can observe $X_1 = x_1$, and I wonder what the distribution $\boldsymbol{X} \ \mid X_1 = x_1 \quad \text{or} \quad \begin{bmatrix} x_1 \\ X_2 \\ X_3 \end{bmatrix}$ is. I think this is related to my first question. Please give me some insights if you can. Thank you so much.


Is there a way to use an animated gif as ImageBrush's ImageSource?

The following code works, but the loaded gif isn't animating. It looks like the imagebrush uses the gif's first frame for displaying. I'd like to get the gif moving if it's possible.  string imagePath = $"pack://application:,,,/Resources/Images/{imageName}.gif"; return new ImageBrush() {     ImageSource = new BitmapImage(new Uri(imagePath)),     TileMode = TileMode.Tile,     ViewportUnits = BrushMappingMode.Absolute,     Viewport = new Rect(0, 0, CELL_SIZE, CELL_SIZE), };


Failing Case I ran across an UnboundLocalError exception that I could not understand. I isolated the simplest chunk of the code: def wrapper_func():    x = 0    def test_unbound():        x += 1        return x    return test_unbound()  Then if I call it: >>> wrapper_func() Traceback (most recent call last):   File "<stdin>", line 1, in <module>   File "<stdin>", line 6, in wrapper_func   File "<stdin>", line 4, in test_unbound UnboundLocalError: local variable 'x' referenced before assignment  But as I understood it, x should be available to the inner function. Functioning Case I tested it by doing something almost identical: def outer_func():    x = 1    def inner_func(val):       print(val + x)    inner_func(2)  If I test this out, no error: outer_func() 3  What Am I Missing? Can someone help me understand why the failing case fails and the successful case works?


I've been learning about Quantum Dynamics, time evolution operators, etc. I am confused about the notation used in integrals. Normally I am used to integrals written in this way (with $dx$ on the right side):  $$\int f(x)dx$$  In this manner of notation, I can easily see the integrand as it is sandwiched by the integral sign and the $dx$. However, I often see integrals written in this way (with $dx$ beside the integral sign):  $$\int dx f(x)$$ Is this notation not ambiguous? This is especially confusing for me when used in products, as I cannot identify what is the integrand sometimes. For example, I don't understand which is true in the following (when evaluating time evolution operator): $$\begin{align}\left(\int ^t_{t_0} dt' H(t')\right)^2\stackrel{?}{=}\int ^t_{t_0} H(t') dt'\int ^t_{t_0}  H(t'')dt''\\\stackrel{?}{=}\int ^t_{t_0} dt' H(t')\int ^t_{t_0} dt'' H(t'')\\\stackrel{?}{=}\int ^t_{t_0} dt'\int ^t_{t_0} dt'' H(t') H(t'') \end{align}$$  The last line is especially confusing for me as I'm not sure if the integrand changes. Could I please get clarification for these different notations? Is there a reason for such notation? (If I'm not wrong, it is to group the integrals and the integrands in separate places for convenience? I'm not sure if it sacrifices clarity for this though.)  EDIT: There is also an issue of when operators are involved: $$\begin{align}\int dx \hat{F}(x) \hat{G}(x)\stackrel{?}{=}\int \hat{F}(x)dx\hat{G}(x)\\\stackrel{?}{=}\int \hat{F}(x)\hat{G}(x)dx\end{align}$$ How do you know which operator is in the integrand? And assuming the general case where $\hat{F}$ and $\hat{G}$ do not commute, you cannot write the integral with $\hat{G}(x)$ on the left of the integral. How is this not ambiguous?


I would like to know if the word "data" is plural or singular? I have looked up some dictionaries but failed to find any relevant information. Thanks!


How do I fix invalid filename extension?

Ignoring file 'sublime-text.lis' in directory '/etc/apt/sources.list.d/' as it has an invalid filename extension


I know the speed of light problem has been beaten do death by hundreds of questions and answers, but I wanted to explore a new possibility and perhaps show an indication that light-speed as a constant is a man-made theoretical limit.  Would you please tell me if my musings are incorrect?  Now onto the subject at hand.   Suppose somewhere in the universe there are about 5000 different celestial bodies in a gargantuan solar system, each spread out the distance between the earth and the moon, each weighing approximately the size of 1 earth.   If by certain miracle, the orbits of those celestial bodies (planetoid objects) are arranged as such that 1) they are on the same plane, and b) all bodies line up almost perfectly with one another (at the time of the experiment).   It follows that if we launch a space vehicle, say a shuttle, and use gravity assist around those celestial bodies, we could theoretically increase the speed of that vehicle (provided that it doesn't rip itself apart from the inertia) 5000 times. As we have already achieved speeds of 150,000 mph using gravity assist in the past - wouldn't it follow that doing this 5000 times in sequence would eventually break the light speed barrier?


If $x$, $y$ and $z$ are positive integer and $3x=4y=7z$, then What is the least possible value of $x+y+z$?


How do I set focus so I get a blurred background?

I am a newbie and I clicked this photo at around 8 PM:    I was around 1.5m away from  the subject. I wanted to focus on the lady and blur the remaining photo. How can I achieve that?   Should I rely on post processing to always change the focus? Any suggestion would be greatly appreciated.


Make post type more obvious in suggested edits queue

I just got full editing privileges on SO, and started reviewing edits. When checking out my edit history in order to find out how others have decided in some particular cases, I noticed that one post which I  has been deleted a few minutes later. It took me quite some time to realize that the edited post, which looked like a valid question, has been posted as an answer (and thus is obviously NAA). Unfortunately, this information is only shown in the bottom left corner, with low contrast:  After reviewing X questions, this one just slipped through. I obviously learned my lesson, but it might still help preventing similar mistakes: Could you move the post type information to a more obvious location? One could for example adapt the layout from the First Posts Queue, where there is a big dark gray "Question" or "Answer" above the post title.


Why does most galaxies resemble a 2 dimensional plane?

Older galaxies mostly tend the revolve forming a disk. Why are the stars not revolving around the center of the galaxy like a sphere instead similar to electron in an atom?


Is it possible to change /pictures/wallpapers which is used automatically when selecting "use as background image"?

is it possible to change of /pictures/wallpapers which is used automatically when selecting "use as background image" on a picture in a folder?  I have read in another thread that this specific folder is hardwired into nautilus, which is kind of inhibiting the setup for me.  It automatically makes a local copy of the picture, whereever the picture might be, to /pictures/wallpapers, and I don't want that.   The folder/ the issue is not mentioned in the "marked as duplicate:XDG paths".  I see no way to change this, can someone help me out?


Prove that if $A$ is positive, then $\exists\;\alpha>0$ such that $\langle Ax, x \rangle\geq \alpha|x|^2$ for $x\in\Bbb{R}^n$

Let $M_{n\times n}(\Bbb{R}).$ We say that $A$ is positive if $\langle Ax, x \rangle>0$ for $x\neq 0.$  I want to prove that if $A$ is positive, then $\exists\;\alpha>0$ such that    $\langle Ax, x \rangle\geq \alpha|x|^2$ for $x\in\Bbb{R}^n.$  Please, I need help for this! Proofs and references will be highly regarded!


I'm having a little problem getting an information. In my plugin, I got a situation where I have to throw, in a very specific situation, a 403 error. But I can't find in the documentation if there is a recommended way to throw a 403, because WP LOVES wrap everything it's own way.  So! Do you know a way to trigger a 403 manually ?  Thanks


What is this virtual memory for the applications on macOs?

I had a look in the activity monitor and when I pulled more information about TabNine, I didn't quite understand the concept of "virtual memory". It says "390GB". How can it have a virtual memory of 390GB when I have a base variant mac with 8GB|256GB spec ?


What is the purpose of "serializable" interface in Java when every object is serializable automatically?

I've read that the "Serialization is the conversion of an object to a series of bytes."  But, this definition is true for every Java object since all Java objects are represented as bytes in memory anyways.  What is the purpose of implementing "Serializable" interface if all java objects can be represented as bytes anyways?  My guess is that implementing "Serializable" interface acts as some flag (you don't even need to implement any methods), but doesn't it make more sense to have an interface called "NotSerializable"?  EDIT: I found that this question is a duplicate of previous question:   I also found a good documentation:   Thanks for the answers!


how to delete constraint when you don't remember constraint name

I've add a constraint on my table named cours a few days ago with mysql. the problem is that i want to delete the constraint and I don't remember the constraint's name I've used. When I want to delete the constraint they ask me to check if it exist  ALTER TABLE cours DROP FOREIGN KEY idEtudiant;   I expect my constraint to be removed but they say that is not exist


Restarting in safe mode without using the shift key under Mojave

I'm trying to restart my MBP (now running Mojave) in safe mode, and for whatever reason holding down shift isn't doing the trick (this complaint is scattered across the internet). Apple  this alternative for cases in which you don't have a keyboard:   Access the command line by opening Terminal remotely, or logging into the computer using SSH. Use the following Terminal command: sudo nvram boot-args="-x"    Unfortunately, when I run this command I get nvram: Error setting variable - 'boot-args': (iokit/common) not permitted. Googling this error gets me a  to this bit of info:     ...you must use the nvram command to properly set boot-args NVRAM   variable. Starting with macOS Sierra, you must be booted to the   recovery partition to run this command.   Booting from the recovery partition sounds even harder than getting into safe mode, so it appears I am back to square one. Are there any other ways to get to safe mode?


Multiple leader lines on one annotation (non feature-linked)

Is it possible to link multiple leaders lines to one piece of annotation?  I'm working in ArcGIS 10.2 Desktop Advanced with non-feature linked geodatabase annotation. I have hundreds of numbers labeling various polygons, but some polygons share a number. Instead of creating multiple numbers/annotations for each polygon I'd like to have one number with multiple lines pointing to each polygon.   So, in the image below, the number 5 corresponds to multiple polygons. Here I've moved 5 from it's ideal location to show that the second leader line is not connected to the number annotation. My workaround has been to create another piece of geodatabase annotation with a blank text string to serve as a placeholder for a leader line. The other option was to use map/graphic annotation to create the second leader line, but with the multiple disadvantages of not being in the same annotation feature class as the number annotation.    My goal would be for each piece of number annotation to be connected to multiple leader lines like appears below.


My friend asked me if $\displaystyle \lim_{n \to \infty}\frac{2}{n(n+1)}=-12$ and burst into laughter.  I'm a little bit confused because I thought the limit is $0$.  Is this a joke or something?


Virtualbox 4.3 causing error on running any guest in 16.10

Every time I start any virtual machine it give's me error:  Kernel driver not installed (rc=-1908)The VirtualBox Linux kernel driver (vboxdrv) is either not loaded or there is a permission problem with /dev/vboxdrv. Please reinstall the kernel module by executing  '/etc/init.d/vboxdrv setup'as root. If it is available in your distribution, you should install the DKMS package first. This package keeps track of Linux kernel changes and recompiles the vboxdrv kernel module if necessary.  where: suplibOsInit what:  3 VERR_VM_DRIVER_NOT_INSTALLED (-1908) - The support driver is not installed. On linux, open returned ENOENT.  I tried installing kernel driver again but no success. I'm using ubuntu 16.10 and really want that specific version 4.3


Apply jquery to page that loaded to a div

I have a div that load an external page.  index.php

     external.php  Load Another Page   As you can see, loadWow DIV will load external.php.  My question is, how can i change the loaded page on the loadWow by clicking the link from an external page (external.php).  Thank you in advance.


Should we retract badges in case of serial voting by multiple sock puppets?

As far as I know all badges being earned once will be never retracted, e.g. when votes are changed on vote dependent badge like “great answer” etc. But what if the badge was earned by serial voting of unrelated to the badge owner user and when that user(s) is(are) suspended for creating sock puppet accounts. Should the badge be retracted? I think it should. Looking for the community opinions.


Misplaced tooltip in Site Analytics graph

The tooltips in the Posts graph on the  are misplaced. Sometimes, they appear to be part of the next graph (see below) - the arrow indicates the point I was hovering over.  This could be caused by the new responsive design; when I originally reported the bug, I checked two other sites (Ask Different and Chess) which didn't have the new design back then, and there the tooltips appeared reasonably close to the data point (the bottom right one in ).


Steam doesn't start after upgrade to Ubuntu 16.04

After upgrade to Ubuntu 16.04, Steam doesn't start. When I execute it from the command line, I get the following error:  $ steam Running Steam on ubuntu 16.04 64-bit STEAM_RUNTIME is enabled automatically grep: symbol lookup error: grep: undefined symbol: pcre_jit_stack_alloc grep: symbol lookup error: grep: undefined symbol: pcre_jit_stack_alloc grep: symbol lookup error: grep: undefined symbol: pcre_jit_stack_alloc Installing breakpad exception handler for appid(steam)/version(1459463254)


Different filesizes on different computers

I have a file and I want to know its size. On computer 1, I get:  $ ls -lh file > -rw-r--r--. 1 user group 441 May 30 15:41 file   On computer 2, I get   $ ls -lh file > -rw-r--r--. 1 user group 441 May 30 15:41 file   Okay. They agree. The filesize is 441 bytes. But now I use du on computer 1:  $ du -h file > 1.0K    file   and on computer 2:  $ du -h file > 32K    file   Why do they not agree? I assume it has something to do with the cluster size on the filesystem. Now a folder with several subfolders and files and a total size of several 100 Megabytes is about twice as large on computer 2 than it is on computer 1. Why would one use the cluster size as it is on computer 2? It will take up much more space, depending on the typical file sizes.  Filesystem on computer 1 is afs, filesystem on computer 2 is nfs.


When I type in any plaintext to an Enigma machine () the substitution does not seem to follow any pattern. In other words, there is no cycle in the use of enciphering alphabets (defined as the number of switches done when turning a plaintext letter to a ciphertext letter - which can vary from 0 to 26).   But since the key is the alignment of the rotors, there must be a finite key length even though it probably is longer than any plaintext ever would be. I imagine if you keep writing long enough, the rotors will eventually align in a way they already were. If I'm right - how long is the key?  And if the key is much longer than any plaintext, wouldn't that mean the Enimga is a one-time pad? From what I can read, the OTP is defined as an algorithm with a key longer than the plaintext. Is this wrong?


Do instant and sorcery cards reach the graveyard before their effects go on the stack?

For example, will a  kill a  that just came out?


How to solve $\sum_{k=1}^{\infty} ke^{-k}$?

I am interested in  $$\sum_{k=1}^{\infty} ke^{-k}$$  And I can get the closed form on Wolfram Alpha, $\frac{e}{(e-1)^2}$, but I am curious how to derive it. It doesn't appear to be a typical geometric series.


Filter list of Cities with latitude and longitude on given Distance from another City (with lat/long)?

How can I filter a given list of cities with longitude and latitude based on a given distance (in km) from another city with longitude and latitude.   I would like use Google Maps API (javascript) or another solution that fits.   cities = {           ['zürich','47.368650', '8.539183'],           ['City2','21.568650', '2.439183'],           ['City3','41.568650', '4.439183'] }   distance   = 2; //2 km targetCity = ['zürich','47.368650', '8.539183'];   need: getNearCities(targetCity,distance,cities);  Thank you


Add a Question Ban Meter in the profile page

Background  I was recently banned from asking questions, and appealed my case . As I think about my problems, I have begun to realize that I was never notified of the question-ban policy - neither were others like me. To remedy the situation, I propose a question ban meter in a user's profile, which shows how close they are to being banned. The meter would look somewhat like this:   (source: )    New users would begin in the middle (where green and yellow meet.) Using the secretive algorithm, the users would then be able to see if they needed to improve questions (in the red) or if they should continue on their current path (in the blue).  This meter would also be used to help people who have been banned. Their pointer would show up to the right of the red, and as they gradually improved it would slide towards the meter until they were able to ask questions again.  Uses   Users in the blue could give up their "question expertise" to help question banned users. This would add a small amount of user input on the ban algorithm, effectively adding much needed community moderation.   Alternative Idea: These "trusted users" (different from [this][4]) would be able to turn down the severity of the ban from permanent to temporary. The notches would be as follows:   Vote to have this ban reviewed (10 "Question Points") One Month Ban (50 "Question Points") One Week Ban (100 "Question Points") One Day Ban (250 "Question Points") Unbanned (500 "Question Points")  Also, users who were able to do this could pool their points together - this would make it even more of a community moderation process.   People who have a good question reputation would show up further on the list of unanswered questions - this would mean that Stack Overflow visitors could find their answers quicker. It would also act as another incentive for people to ask thoughtful questions.  This would help new users realize that there is a question ban in effect, potentially lowering the number of ban appeals on the    Thoughts? Comments? Questions? Please let me know if you think that this is a good idea (or not) in comments and answer sections.  Edit  Many users have said that Stackoverflow could be "gamed" if this were to go into effect. Before you say that, please try to answer these questions:   What do you mean by "gamed"? If "gamed" means using the system to make sure that questions are not downvoted, or to realize when to focus more on the question... then that is not "gaming" the system - it is using it in the appropriate manner. This is somewhat unrelated to the origninal question, but they are definitely intwined: What is the reason for the secrecy of the algorithm? If people knew what it was, most people would try to avoid doing things that would hurt themselves instead of using it to somehow "ruin" the experience for others.


I want to calculate the integral, $\int_0^x \frac{t^n}{1-t} dt$, where $n \in \mathbb{N}$ and $x \in (0;1)$ are some constants, but I do not know how to do it. I tried the following methods:  Decomposition of $\frac{t^n}{1-t}$ into the sum of primitive fractions  $$ \begin{align*} \int_0^x \frac{t^n}{1-t} \, dt  &= \int_0^x \frac{(1-(1-t))^n}{1-t} \, dt \\  &= \sum_{k=0}^n (-1)^{k}C_n^k \int_0^x (1-t)^{k-1} \, dt \\  &= \sum_{k=0}^n (-1)^{k}C_n^k \int_{1-x}^1 t^{k-1} \, dt \\  &= -\ln(1-x) + \sum_{k=1}^n (-1)^{k}C_n^k\frac{1 - (1-x)^k}{k}  \end{align*} $$ And here I am stuck, not knowing how to find the closed form of this sum.  Integration by parts  $$ \begin{align*} \int_0^x \frac{t^n}{1-t} \, dt  &= \frac{1}{2} \int_0^x \frac{t^{n-1}}{1-t} \, dt^2 \\  &= \frac{x^{n+1}}{2(1-x)} - \frac{1}{2} \int_0^x \frac{t^2 ((n-1)t^{n-2}(1-t)  + t^{n-1})}{(1-t)^2} \, dt \\  &= \frac{x^{n+1}}{2(1-x)}  - \frac{n-1}{2} \int_0^x \frac{t^{n}}{1-t} \, dt  - \frac{1}{2} \int_0^x \frac{t^{n+1}}{(1-t)^2} \, dt  \end{align*} $$ $$\int_0^x \frac{t^n}{1-t} dt = \int_{1-x}^1 (1-t)^n d \ln(t) = -x^n\ln(1-x) + n \int_{1-x}^1 (1-t)^{n-1}\ln(t)dt$$ Neither of the right parts of those equalities seems to be any easier than the initial integral.  WolframAlpha   Standard computation time exceeded... Try again with Pro computation time


VT-x is not available, but is enabled in BIOS

Recently I started having an issue with VT-x on my Windows 10 running on HP EliteBook. I was using Oracle VirtualBox to run some VMs on it before and VT-x was enabled in BIOS and was working fine.  I started getting VT-x is not available error every time I was trying to start any of my VMs. That started happening after I installed Docker on my machine, so I tried uninstalling it and rebooting. Didn't help.  I checked BIOS settings and it says VT-x is enabled but checking with Intel(R) Processor Identification Utility shows that VT-x is not supported and Oracle VirtualBox also doesn't see it.  There were no hardware changes and the only software change was installing/uninstalling Docker.  How can this issue be fixed?


How do I check if someone accessed my computer?

I need to check the list of files accessed in my computer (ex: yesterday on particular time). Is it possible?   Or   I need to check whether anybody accessed my computer (when I left it unlocked) or not for a particular time.


Curly brackets with long content cross the margin

I wonder if there is a way to break a line when it is too long with a curly bracket crossing the margin. Thanks.  \documentclass[12pt]{article} \begin{document} blablabla blablabla blablabla blablabla blablabla  blablabla blablabla blablabla. Here comes a long form, and it is extremely long. $\{1,2,3,4,5,6,7,8,9,10,1,2,3,4,5,6,7,8,9,10\}$.    \end{document}


When taking double/triple derivatives of multivariable functions, we see that no matter which order we take the derivative in, as long as we take the derivative od the function with respect to the same number of variables, the same number of times, our answer is the same? Is there an intuitive explanation for this? I cannot seem to understand how.


I am tasked to sketch the locus of complex numbers $z$ that satisfies $$(z-2+i)^2 + (z^*-2-i)^2 + 2zz^* + 6 = 0$$ I was wondering if there’s a special trick to this question, or if this is only solvable by plugging in $z=x+iy$ ? I noticed that the second term is the conjugate of the first, and wanted to substitute $w = z-2+i$, however this gives me a complicated expression for $zz^*$ which makes it more confusing. Is there a trick I’m missing out? Thanks! Edit: I have already solved it through direct substitution (parabola intersecting real axis at $x=3$ and $x=-1$) but it took a good 5 minutes or so, expanding everything correctly, which seems rather long (I was attempting it under exam conditions). I was just wondering if it is possible to exploit the $w$ substitution I made in particular.


Why does the likelihood function of a binomial distribution not include the combinatorics term?

So the likelihood function for a binomial distribution is:    Why is the likelihood function above not multiplied by a combinatorics term: n! / (x! * (n - x)!)   If the likelihood function is interpreted as the probability of an outcome occurring x times out of n trials as the parameter, θ, varies, shouldn't there be a combinatorics term as that would provide the actual probability?  Thanks!


Perfectly scale figure to the rest of a page

I want a figure to fit perfectly inside a slide in beamer. This means that it should scale to the smallest dimension between width and height, maintaining proportions, and allowing space to the rest of the content of the slide.  I wrote my following example using code from   \documentclass{beamer} \usepackage{calc} %code from https://blogs.gnome.org/muelli/2011/04/perfectly-scale-an-image-to-the-rest-of-a-page-with-latex/ \newlength{\textundbildtextheight} \newcommand{\textundbild}[2]{ \settototalheight\textundbildtextheight{\vbox{#1}} #1 \vfill \begin{center} \includegraphics[width=\textwidth,keepaspectratio=true,height=\textheight-\the\textundbildtextheight]{#2} \end{center} \vfill                                                                                } \begin{document} \begin{frame}{Title}   \textundbild{description}{fig.png} \end{frame} \end{document}   However, using this way, the figure still does not fit perfectly.  See that the figure overlaps the navigation bar on the bottom of the page.    How do I automatically scale a figure so it respects the content of the frame?


How to align text and checkboxes consistently?

I'm making a little quiz. My problem is when ever the first question is generated the text and checkbox isn't aligned properly. All the other questions are fine. If I refresh the page it is fine as well. At first I thought maybe I could find a way to automatically refresh the page one time, but I was wondering if there is something simpler.However, if that's the only way, I'm all ears.    var pos = 0,   test, test_status, question, choice, choices, chA, chB, chC, correct = 0; var questions = [   ["Question 1?", "Answer A", "Answer B", "Answer C", "B"],   ["Question 2?", "Answer A", "Answer B", "Answer C", "C"],   ["Question 3?", "Answer A", "Answer B", "Answer C", "A"],   ["Question 4?", "Answer A", "Answer B", "Answer C", "A"],   ["Question 5?", "Answer A", "Answer B", "Answer C", "C"] ];  function _(x) {   return document.getElementById(x); }  function renderQuestion() {   test = _("test");   if (pos >= questions.length) {     test.innerHTML = "
You got " + correct + " of " + questions.length + " questions correct
";     _("test_status").innerHTML = "Test Completed";     pos = 0;     correct = 0;     return false;   }   _("test_status").innerHTML = "Question " + (pos + 1) + " of " + questions.length;    question = questions[pos][0];   chA = questions[pos][1];   chB = questions[pos][2];   chC = questions[pos][3];   test.innerHTML = "
" + question + "
";   test.innerHTML += "<input style='float:left;' type='checkbox'  name='choices' value='A'>
" + chA + "
";   test.innerHTML += "<input style='float:left;' type='checkbox'  name='choices' value='B'>
" + chB + "
";   test.innerHTML += "<input style='float:left;' type='checkbox'  name='choices' value='C'>
" + chC + "
";   test.innerHTML += "<button onclick='checkAnswer()'>Submit Answer</button>"; }  function checkAnswer() {   choices = document.getElementsByName("choices");   for (var i = 0; i < choices.length; i++) {     if (choices[i].checked) {       choice = choices[i].value;     }   }   if (choice == questions[pos][4]) {     correct++;   }   pos++;   renderQuestion(); } renderQuestion();


I cannot update the ubuntu-keyring package on my Ubuntu WSL.  I tried to run sudo apt update ubuntu-keyring and this is the command output:  Reading package lists... Done Building dependency tree Reading state information... Done The following packages will be upgraded:   ubuntu-keyring 1 upgraded, 0 newly installed, 0 to remove and 86 not upgraded. Need to get 0 B/26.9 kB of archives. After this operation, 6,144 B of additional disk space will be used. Preconfiguring packages ... (Reading database ... 91158 files and directories currently installed.) Preparing to unpack .../ubuntu-keyring_2018.09.18.1-4_all.deb ... Unpacking ubuntu-keyring (2018.09.18.1-4) over (2012.05.19) ... dpkg: error processing archive /var/cache/apt/archives/ubuntu-keyring_2018.09.18.1-4_all.deb (--unpack):  trying to overwrite '/usr/share/keyrings/ubuntu-cloudimage-keyring.gpg', which is also in package ubuntu-cloudimage-keyring 2013.11.11 Warning: The postinst maintainerscript of the package ubuntu-keyring Warning: seems to use apt-key (provided by apt) without depending on gnupg or gnupg2. Warning: This will BREAK in the future and should be fixed by the package maintainer(s). Note: Check first if apt-key functionality is needed at all - it probably isn't! Warning: apt-key should not be used in scripts (called from postinst maintainerscript of the package ubuntu-keyring) Warning: 'apt-key update' is deprecated and should not be used anymore! Note: In your distribution this command is a no-op and can therefore be removed safely. Errors were encountered while processing:  /var/cache/apt/archives/ubuntu-keyring_2018.09.18.1-4_all.deb E: Sub-process /usr/bin/dpkg returned an error code (1)  I also tried to download the ubuntu-keyring_2018.09.18.1-4_all.deb file and then install it using sudo dpkg --install ubuntu-keyring_2018.09.18.1-4_all.deb, but the same error shows up.


Input format for response in binomial glm in R

In R, there are three methods to format the input data for a logistic regression using the glm function:    Data can be in a "binary" format for each observation (e.g., y = 0 or 1 for each observation); Data can be in the  (e.g., y = cbind(success, failure)) with each row representing one treatment; or Data can be in a weighted format for each observation (e.g., y = 0.3, weights = 10).   All three approach produces the same coefficient estimates, but differ in the degrees of freedom and resulting deviance values and AIC scores. The last two methods have fewer observations (and therefore degrees of freedom) because they use each treatment for the number of observations whereas the first uses each observation for the number of observations.  My question: Are there numerical or statistical advantages to using one input format over another? The only advantage I see is not having to reformat one's data in R to use with the model.   I have looked at the , searched on the web, and this site and found one tangentially related , but no guidance on this topic.   Here is a simulated example that demonstrates this behavior:  # Write function to help simulate data drc4 <- function(x, b =1.0, c = 0, d = 1, e = 0){     (d - c)/ (1 + exp(-b * (log(x)  - log(e)))) } # simulate long form of dataset nReps = 20 dfLong <- data.frame(dose = rep(seq(0, 10, by = 2), each = nReps)) dfLong$mortality <-rbinom(n = dim(dfLong)[1], size = 1,                               prob = drc4(dfLong$dose, b = 2, e = 5))  # aggregate to create short form of dataset dfShort <- aggregate(dfLong$mortality, by = list(dfLong$dose),                       FUN = sum) colnames(dfShort) <- c("dose", "mortality") dfShort$survival <- nReps - dfShort$mortality  dfShort$nReps <- nReps dfShort$mortalityP <- dfShort$mortality / dfShort$nReps  fitShort <- glm( cbind(mortality, survival) ~ dose,                   data = dfShort,                   family = "binomial") summary(fitShort)  fitShortP <- glm( mortalityP ~ dose, data = dfShort,                    weights = nReps,                        family = "binomial") summary(fitShortP)  fitLong <- glm( mortality ~ dose, data = dfLong,                  family = "binomial") summary(fitLong)


I am trying to update with sudo and get's this error from the terminal below:  404  Not Found [IP: 13.80.99.124 80] Reading package lists... Done                                                   N: Repository 'http://archive.ubuntu.com/ubuntu groovy InRelease' changed its 'Suite' value from 'groovy' to 'groovy-backports' E: Repository 'http://archive.ubuntu.com/ubuntu groovy InRelease' changed its default priority for apt_preferences(5) from 500 to 100. N: This must be accepted explicitly before updates for this repository can be applied. See apt-secure(8) manpage for details. W: Conflicting distribution: http://packages.microsoft.com/repos/code stable InRelease (expected stable but got disco)  Should i change something or??


This is probably related to whether one should capitalize Internet or not. I am looking for the correct spelling of wifi when referring to a wireless connection to the Internet. I want to tell the users of my iPhone app that they cannot use their cellular network to watch the HD videos.  If I use the capitalized and hyphenated version as seen on , will I be referring to the Wi-Fi brand rather than the concept of wifi?      "Wi-Fi" is a trademark of the Wi-Fi Alliance and the brand name for   products using the IEEE 802.11 family of standards.   Some dude on  made this claim with no explanation:      WiFi" is a bit better than "wifi" as it asserts the etymology, compare   history of usage of "hifi" from which it derives. – Steve-o Aug 29 at   3:59


Where in Tbilisi can I get very early morning public transport towards Azerbaijan?

I will be arriving in Tbilisi on Tuesday 4 april at 04:30, and need to get to Baku from there as quickly as possible by bus.  My questions is, what bus station should I go to for transport at around this time?  Didube, Ortachala, Sadg. Moedani etc?  Any form of public transport is good - buses, mashrutkas, shared taxis, etc - so long as I can reliably find it at around that time in the morning.


Mapping Node, Box projection, and rotation

Goal  I'm trying to map a texture on a cube;   Since my texture is not exactly fitting the correct orientation, I need to rotate it. The results are not as expected.  Setup description  I'm using the setup shown in the following pictures. I've set the projection mode to Box have the texture visible on all faces. Texture mode is set on Repeat to avoid undesired clamping (default value). What I'm trying to achieve is to have the planks horizontal instead of vertical on the front face (rotate around X axis). The rotation is applied in a Mapping Node.   Results   The face I need is properly rotated, but the others get this blurry effect, which reminds me of the "Clamp" mode in OpenGL. Is this expected behavior ? How to solve this ?  **Additional note (edits) **  Both the cube and the material are simplified versions of the original problem. The meshes I have are more complex, a few thousands faces, and with complex shapes (such as switches or sockets outlets). Very few faces are not aligned with the world axes, and thus they can be ignored. The material needs to be applied on various shapes, so UV map can't be made manually. The purpose of this is to automatically create a diffuse map of each textured item, where every face with a similar direction/normal would have a similar rotation applied.  For simplificity sake, the cube seems to be a good sample


Duplicate edits submitted at nearly the same time both go through

I posted  a short while ago and accidentally left a few zero-width spaces from a bug I was testing earlier. odnU pointed out my error, and we both made edits to fix it, which you can see in  (edits #2 and #3). We both made the exact same edit (removing the 10-20 spaces), and submitted the edit within 2 seconds of each other. The odd thing is that the second edit created a new revision in the history, even though it changed nothing from the revision before it.  I have no idea how this is possible, but I'm pretty sure it's not supposed to be.


I need to prove that:  $$0 = \sum_{k=0}^n\binom{n}{k}(−1)^k$$  Any ideas, please?


__init__.py imports expose also modules I use, not only my own classes

There's something that I'm not grasping about python imports. I've read dozens of articles but I'm not finding a satisfactory answer. The situation is this:  I'm writing a package made of several modules. Let's say that the package is named pack1. In the __init__.py file, in order to expose the classes and functions I defined in my modules, I wrote:      from .module1 import *     from .module2 import *     ...   Now, in module 1:      from math import sqrt  # a tool that I need      class class1:          <body>      class class2:          <body>     ....     class class100:          <body>   My problem is that when I      import pack1   in another project, I see sqrt in pack1's namespace. Do I have to import each one of the 100 classes separately in the __init__.py file in order to avoid this and keep my namespace clean? Do I have to do some hack with the inspect module in __init__.py in order to identify the classes that were defined and not imported (I think this would be very ugly)? Or, as I suspect, I'm mistaking something about how I should handle the module structure or the import statements?


A question about the arctangent addition formula.

In the arctangent formula, we have that:  $$\arctan{u}+\arctan{v}=\arctan\left(\frac{u+v}{1-uv}\right)$$  however, only for $uv<1$. My question is: where does this condition come from? The situation is obvious for $uv=1$, but why the inequality?  One of the possibilities I considered was as following: the arctangent addition formula is derived from the formula:  $$\tan\left(\alpha+\beta\right)=\frac{\tan{\alpha}+\tan{\beta}}{1-\tan{\alpha}\tan{\beta}}.$$  Hence, if we put $u=\tan{\alpha}$ and $v=\tan{\beta}$ (which we do in order to obtain the arctangent addition formula from the one above), the condition that $uv<1$ would mean $\tan\alpha\tan\beta<1$, which, in turn, would imply (thought I am NOT sure about this), that $-\pi/2<\alpha+\beta<\pi/2$, i.e. that we have to stay in the same period of tangent.  However, even if the above were true, I still do not see why we have to stay in the same period of tangent for the formula for $\tan(\alpha+\beta)$ to hold. I would be thankful for a thorough explanation.


When running isc-dhcp the leases file seems to grow indefinitely (several hundred MB). If I restart the isc-dhcp service, the file shrinks to 1.5MB.   How can I have isc-dhcp flush expired records periodically without restarting the full service?


Convergence $I=\int_0^\infty \frac{\sin x}{x^s}dx$

Hi I am trying to find out for what values of the real parameter does the integral $$ I=\int_0^\infty \frac{\sin x}{x^s}dx $$ (a) convergent and (b) absolutely convergent.     I know that the integral is convergent if $s=1$ since $$ \int_0^\infty \frac{\sin x}{x}dx=\frac{\pi}{2}. $$ For $s=0$ it is easy to see divergent integral since $\int_0^\infty \sin x\, dx$ is divergent.  However I am stuck on figuring out when it is convergent AND or absolutely convergent.  I know to check for absolute convergence I can determine for an arbitrary series $\sum_{n=0}^\infty a_n$ by considering $$ \sum_{n=0}^\infty |a_n|. $$ If it helps also $$\sin x=\sum_{n=0}^\infty \frac{(-1)^{2n+1}}{(2n+1)!} {x^{2n+1}}$$. Thank you all


On a new install with default Twenty Fifteen theme and no activated plugins. I used Really Simple CSV Importer to import ~4000 pages with title and one word content for each. This is to have my pages ready for use with Advanced Custom Fields (pages will have dozen text areas metaboxes, not really using any advanced ACF features like repeaters or anything)  edit.php and post-new.php take a long time to load on a good, not crowded SSD, high RAM server (confirmed this with others on the server and my host).   I guess the number of pages are the factor. I wanted to see what effect deactivating ACF and all other plugins have. No noticeable difference, I turned off all screen options and reduced the 'Number of items per page' too. So now the edit.php?post_type=page only shows pages titles and post-new.php?post_type=page only the title and content boxes and Publish buttons.  When I looked at the page source I guess I see the issue, on both edit.php and post-new.php after all I have done above (deactivate, turn off, etc.)  a list of all my pages are loaded like:

           Page Attributes

Parent
 Parent <select name='parent_id' id='parent_id'> <option value="0">Main Page (no parent)</option> <option class="level-0" value="3">Page 1</option> <option class="level-0" value="4">Page 2</option> . . . <option class="level-0" value="4300">Page 4000</option> </select>    Is it possible to not have that load every time? If so, using a filter or plugin?


Why isn't $\lim \limits_{x\to\infty}\left(1+\frac{1}{x}\right)^{x}$ equal to $1$?

Given $\lim \limits_{x\to\infty}(1+\frac{1}{x})^{x}$, why can't you reduce it to $\lim \limits_{x\to\infty}(1+0)^{x}$, making the result "$1$"?  Obviously, it's wrong, as the true value is $e$.  Is it because the $\frac{1}{x}$ is still something even though it's really small?  Then why is $$\lim_{x\to\infty}\left(\frac{1}{x}\right) = 0\text{?}$$  What is the proper way of calculating the limit in this case?


I just wanted to buy more unicoins using the "alternative payments - valuables - bacon", but this procedure fails. What should I now do with all this prepared bacon?


Whatever is inside finally blocks is executed (almost) always, so what's the difference between enclosing code into it or leaving it unclosed?


Calling a class defined from another module

I am calling the method defined in a class implemented from another module using the following code.  use Drupal\module_name\MyClassName;  $instance = Drupal\module_name\MyClassName::getinstance($host, $user, $pass);   My code doesn't work, as I get an error about a class not found. What am I doing wrong?  The class is contained in module/src/controiller/controller_name.php.


How did I exceed the daily reputation limit?

I didn't  even know there was a daily reputation limit until I earned this badge today, and I appear to have exceeded it already.  Curious.


How do you make Google's interface always be in your chosen language?

Google's interface and search results don't always appear in my preferred language, English.  I'm located in Mexico City and, although I generally have no problem with Spanish, I would prefer search results in English most of the time.  (The exception is when I'm using search terms in Spanish.)  I'd also prefer the interface to be in English, but that's far less important to me than search results.  Google looks at your IP to decide where you're coming from and thus what language to present results in.  So, when I type www.google.com into the URL bar, it redirects me to www.google.com.mx.  Is there a way to force Google to use one language all the time?  Here are some things I've done and tried:  0) I have a Google account, and I've configured it such that it should know that English is my preferred language.  I don't often explicitly log out of Google, so generally Google knows I'm me and my preferences when I access its services.  1) I've configured my browser to ask for pages in English.  Very few sites support this feature at all; Google isn't one of them.  2) From www.google.com.mx, I can click on "Google.com in English".  This works until, I think, I close the browser.  2a) From www.google.com.mx, I can go into account configuration, which is English.  From then on, everything's in English.  3) I can append &hl=en (Human Language = English) to the end of the URLs of result pages.  2, 2a, and 3 all "work", but they're all mildly annoying.  I'd rather avoid them if I could.  (At the risk of stating the obvious, English and Spanish are the languages I'm dealing with, but I imagine that, say, a francophone using Google from Korea would run into basically the same issue.)


Pages like this that have many embedded videos, freeze Ubuntu for a long time, then Flash crashes.  Is this just a Ubuntu 64-bit problem? Do I need more than my current 2gb ram?   I'm surprised that it can completely freeze up Firefox, since Firefox uses a separate process for plugins? Should this be reported as a bug, in Firefox, or Ubuntu?


Android Null pointer exception while using Async Task method

While executing Async Task in android and getting Json response and while converting response into JSONArray,i am getting NUll pointer Exception. I am trying fron two days Please help me. Here is the code to get the Json String. error is at task.get().  DownloadTask task=new DownloadTask();         task.execute(new String[]{"URL"});         try {             jsonArr=new JSONArray(task.get());                 Toast.makeText(getApplicationContext(), jsonArr.toString(), Toast.LENGTH_LONG).show();                 for (int i = 0; i < jsonArr.length(); i++) {                     obj = jsonArr.getJSONObject(i);                     name = obj.getString("name");                     phno = obj.getString("phone");                     dcount = obj.getString("count");                 }         } catch (JSONException e) {             e.printStackTrace();         } catch (InterruptedException e) {             e.printStackTrace();         } catch (ExecutionException e) {             e.printStackTrace();         }   Here Is the Async task code.  class DownloadTask extends AsyncTask<String,Void,String>{          private ProgressDialog mProgressDialog=new ProgressDialog(MainActivity.this);          @Override         protected void onPreExecute(){             mProgressDialog.setMessage("Processing");             mProgressDialog.show();         }          @Override         protected String doInBackground(String... targetURL) {             URL url;             HttpURLConnection connection = null;             try {                  url = new URL(targetURL[0]);                 connection = (HttpURLConnection)url.openConnection();                  connection.setRequestMethod("GET");                 connection.setRequestProperty("Content-Type",                         "application/json");                  connection.setUseCaches (false);                 connection.setDoInput(true);                 connection.setDoOutput(true);               /*   //Send request                 DataOutputStream wr = new DataOutputStream (                         connection.getOutputStream ());                 wr.writeBytes("BID1");                 wr.flush();                 wr.close();*/                  //Get Response                 InputStream is = connection.getInputStream();                 BufferedReader rd = new BufferedReader(new InputStreamReader(is));                 String line;                 StringBuffer response = new StringBuffer();                 while((line = rd.readLine()) != null) {                     response.append(line);                     response.append('\r');                 }                 rd.close();                 return response.toString();              } catch (Exception e) {                 e.printStackTrace();                 return null;              } finally {                  if(connection != null) {                     connection.disconnect();                 }             }         }         @Override         protected void onPostExecute(String result) {              Toast.makeText(getApplicationContext(),result, Toast.LENGTH_SHORT);             mProgressDialog.dismiss();          }     }


Loading GeoDataFrame to PostGIS when GEOM column contains MULTILINESTRING and LINESTRING

How can I load GeoDataFrame (populated from shapefile) to PostGIS when GEOM column contains MULTILINESTRING and LINESTRING e.g.:  LINESTRING (14.2384666 46.6304714, 14.2386703 46.6304123)  MULTILINESTRING ((13.90433020000000042 46.61830880000000121, 13.90393929999999934 46.61873270000000247, 13.90390771785250124 46.61876445408692859),(13.90327032848085764 46.61940531353186401, 13.90327032848085587 46.61940531353186401))   I have tried with "to_sql" but I need to specify GEOM type and when I chose   'geom':Geometry('MULTILINESTRING', srid=4326)}   I got an error: ProgrammingError: (psycopg2.ProgrammingError) can't adapt type 'LineString'


I was wondering if walk slow and walk slowly are both correct or if there's a difference between them.    English isn't my first language and I'm sure the rules I learned would only accept slowly as the right word, because it follows a verb.  When I search for walk slow on Google I still get 250,000 results and for walk slowly I get 525,000 results, so walk slow can't be completely wrong.  Which one is right?


I have a table address and a table route.  Route stores 2 ids of Address and the distance between these Locations -> idStart, idEnd, distance.  +-------+-------+-----+--------+ |idRoute|idStart|idEnd|distance| +-------+-------+-----+--------+ |0      |1      |3    |2698    | |1      |2      |4    |914     | +-------+-------|-----+--------+   +---------+---------+-------------+ |idAddress|country  |city         | +---------+---------+-------------+ |0        |USA      |Indianapolis | |1        |Brasil   |Rio          | |2        |Germany  |Munich       | |3        |Argentina|Buenos Aires | |4        |Italy    |Rome         | +---------+---------+-------------+   `  So i'd like to query and get all routes as follows:  +-------+-------+-------+--------+---------+------+------------+--------+ |idRoute|idStart|idEnd  |CountryS|CountryE |CityS |CityE       |distance| +-------+-------+-------+--------+---------+------+------------+--------+ |0      |1      |3      |Brasil  |Argentina|Rio   |Buenos Aires|2698    | |1      |2      |4      |Germany |Italy    |Munich|Rome        |914    | +-------+-------+-------+--------+---------+------+------------+--------+   If i do some subqueries and outerquery a specific route id it'll work since i got a specific where id=#         SELECT             ro.idRoute,             ro.idStart,             ro.idEnd,             ro.distance,             ro.time,             (select a.country from address a              left join route ro                  on (a.idAddress=ro.idStart)             WHERE ro.idRoute='.$id .') as country_start,             (select a.country from address a              left join route ro                  on (a.idAddress=ro.idEnd)             WHERE ro.idRoute='.$id .') as country_end, FROM route ro         LEFT JOIN address a ON (a.idAddress=ro.idStart)         LEFT JOIN countries c ON (a.country=c.code)         WHERE ro.idRoute='.$id . $this -> presetFilter . ';   But in most cases i'd need all records of route and i cant get this working since for the subqueries i would miss the where Statements.  Something like outer query -> "set fieldname as outerResult" and use outerResult in where Statement of inner query????


I am working on a model and facing some problems. The problem is that some of the triangles have different color and i want to make it same color as the whole model is. In the image you will see that some of triangles are in light red color and the remaining model is in dark red color, so how can i change that light red color to dark red color, one material is applied on that mesh.


Should the notation “$\log x$” mean the decimal logarithm?

I'm confused how do i can justifying to my students the difference between the two Notation “$\log x$” and “$\ln x$” however i checked the definition  in wikipedia. Really many people understand that the notation “$\log x$” must be the decimal logarithm (base $10$). But what I think is $\log x$ can be written as $\log_{e}x$ which is $\ln x $. The difference occurs only when I put the base $a$ as $\log_{a}x$ different from $e$.  My question here is:     Should the notation  “$\log x$” mean the decimal logarithm and how can I give the correct notation with the correct definition to my students?   Thank you for any help


div inside col takes the full width (bootstrap 4)

I have the following code:

test

  The div with the text "test" uses the full width inside the col. So the whole cols background is #1b6d85. But why? I didnt't declare the width of this div so ´shouldn't it be only the width of the text?


I have problems in using Biblatex, when I compile when file,  the references are not shown and an error message of "empty bibliography" is shown.  Then I tried find a biblatex template provided by the overleaf platform. The following is the link of the template I found.  I open the file in overleaf, and everything works fine when I compile the file, I can see the references and citations correctly.  Then I tried to delete the contents of the .bib file, and then I compile, a message of "empty bibliography" is shown. This is also ok, because the .bib is blank.  However, when I put back the contents to the .bib file, and compile, the message of "empty bibliography" is shown again, and no referencing can be seen.  I tried the same procedure in two different computers (with the same overleaf account), and the same problem appears.  I would want to know how to fix the problem. Thank you in advance.


Don't understand this switch and why the output is that

I don't understand why the output is only Warren. And what does switch(money,money*2) mean?  #include<stdio.h> #define L 10 void main(){      auto money=10;      switch(money,money*2){         case L: printf("William");                break;         case L*2: printf("Warren");                break;         case L*3: printf("Carlos");                break;         case L*4: printf("Inqvar");                break;         default: printf("Lawrence");      } }


Is there a simple way to create an arch? Different type of arches on . I'm interested in the Round arch or Elliptical arch type of arches.


Notify upvoters and answerers when a question is closed

In an  about whether closed questions should be deleted unless improved, a painful corner case has emerged: what to do with bad questions that have good answers?  Whatever the answer to this question, I think we should do our best to enlist those users interested in a question to improve it so that it may be reopened. Arguably, answerers should be on top of the list and upvoters directly afterwards; these are users who thought the question (and/or its answers) are worth keeping.  Now, as far as I know nothing prevents this from happening:   I find a question I like. I upvote and/or answer the question. I go on with my life. Some time later, the question is closed. Some time after that, the question is deleted. If I keep an eye on my rep, now I realise something has happened. Unless I can see deleted questions, I have almost no way of finding the deleted question. Only applicable for answerers; upvoters might never know the question vanished.   So, users that thought the question worthy are kept out of the loop. Why is that? I propose we should send users who upvoted a question and/or answered it a notification when it is closed, asking them to improve the question and vote/flag for reopening if they think the question should be saved.  Aside from improving the site by keeping more good content around, this extends some courtesy towards those who invest time to answer a question even if it is not stellar. It also creates awareness of the possibility for involvement in the quality control process.  Related question:  (old, no official reaction)


Forward declaration or complete definition required

Although i have been using forward declaration for a considerable amount of time but never gave a thought to it seriously (my mistake)  Would be helpful if someone could give me pointers or any link regarding following queries :   How do we determine if we require a forward declaration or include is required ? How does compiler actually works in such cases ? any overhead ? Suppose i have two interdependent classes A and B. Both of them uses objects of each other, do i need to forward declare in both the classes.


Apex REST API - Unable to set StatusCode to 429

I am trying to set the status code to 429 for Too many request using the code below:  if(Limits.getQueries() < Limits.getLimitQueries()){               upsert UpdateData;               }               else if((Limits.getQueries() >= Limits.getLimitQueries()))               {                   RestContext.response.statusCode = 429;                   UpdateError[] err = new UpdateError[]{                    new UpdateReturnError(UpdateData.Id, 'Too many Requests', 'Error updating MessageID ' + msg.MessageId)                 };                 RestContext.response.responseBody = Blob.valueOf(JSON.serialize(err));                 RestContext.response.addHeader('Content-Type', 'application/json');                 break;               }             }   I am getting the following error in the raw response:    Can someone help me out with this?


What desirable properties should an S-box have?  My current standard selection process is to just pick them at random and verify that they fit the following criteria:   The probability that any random two bits $S[a]_b$ and $S[c]_d$ are equal (for any random $a$, $b$, $c$ and $d$) is 50%. The probability that any random two bits $S[a]_n$ and $a_n$ are equal (for any random $a$ and $n$) is 50%. No entries exist such that $S[a] = a$ No entries exist such that $S[a] = \bar{a}$   Are there any other important properties that need to be applied?  Edit My reasons for asking are that I wish to combine this S-Box design with a CBC mode cipher as discussed on .


Links that are italics and bold not showing as links in Mobile Web

I saw a link to IMDB in  on Movies.SE site. This link text has been italicized and emboldened by the user. It says Time Enough At Last.  And now the link is hidden. It loses its blue coloring that other links receive,  making it impossible to know it is a hyperlink. Can this be fixed? It's likely a conflict in CSS rules.  Android 4.4, default browser (chromium), Galaxy S5.  Notice the Wikipedia link is blue. I had not visited either url so they should not be colored differently. The same page, in full site/desktop mode, shows the same link blue, so this is just a problem on mobile web.  Just tested, on regular Safari, with the iPhone 6 user agent, it also has the same issue.    The Inspector shows the problem. The em style is overriding the a > em somehow in the mobile CSS.  em { color: #0C0D0E; } a, a:visited { text-decoration: none; color: #07C } a, a > em { color: #07C }


I'm having some trouble running the code I wrote.  meal = float(raw_input("How much did your meal cost? "))  tax = 6.75 / 100 tip = 15 / 100  total = (meal * tax) * tip  print total   You can see above that I made this "tip calculator". Whenever I enter a number, it returns with zeros. It seems like it's skipping the entire calculation part.  Any solution?


A word that refers to saying something in an attempt to anger or embarrass someone into doing something that they don’t want to do?

I’m looking for a word to refer to the act of trying to embarrass someone to the point that they do something they don’t want to do.  Example: Let’s say all of your friends are jumping off of a cliff into a lake, but you don’t want to, for whatever reason. One friend remains at the top with you, trying to convince you to jump. One tactic they use is to try and embarrass you enough or anger you into doing it by saying something along the lines of - “So, basically, you’re too chicken to jump, right?”  I believe I could use the phrase ‘egg on’ for this, but would rather have a singular, more specific word for it. I’m pretty sure there is one, but I just can’t bring it to mind. I’ve considered ‘reverse psychology’, too, but it just doesn’t fit what I’m trying to say.


weak convergence of a bounded linear operator

I need help with this problem  Let $X$ be a reflexive Banach space and $T: X \to X$ a linear operator. Show that $T$ belongs to $\mathcal{L}(X,X)$ if and only if whenever $\{x_n \}$ converges weakly to $x$, $\{T(x_n)\}$ converges weakly to $T(x)$.  any hints or suggestions, thank you!


Should I remove link and put screen shots instead in editing?

Possible Duplicate:          In CSS related questions people put links to sites to show what they want to do. In some cases links are not required only providing a screen shot is enough. So my question is "Should I remove link from such a question and put a screen shot or leave it as it is and comment author to do this?"  Example of such a question is:


When pedaling forward my bike suddenly disingages and goes limp

My Ridgeback Velocity bicycle suddenly disengages and goes limp and loose when pedalling forward, similar as if I'm pedalling backwards.


How to create gaussian blur in ArcGIS for Desktop Advanced with Spatial Analyst?

I am trying to create a gaussian blur for a buffer polygon around a border.    I have Spatial Analyst and ArcGIS for Desktop Advanced, but am not sure if it is possible.  Can anyone suggest a way to do it in ArcGIS for Desktop?


Show $\sum_{k=1}^\infty \frac{k^2}{k!} = 2\mathrm{e}$

I stumpled upon the equation  $$\sum_{k=1}^\infty \frac{k^2}{k!} = 2\mathrm{e}$$  and was just curious how to deduce the right hand side of the eqution - which identities could be of use here? Trying to simplify the partial sums to deduce the value of the series itself didn't help too much thus far.  Edit:  The only obvious transformation is $$\sum_{k=1}^\infty \frac{k^2}{k!} = \sum_{k=0}^\infty \frac{k+1}{k!}$$ but there was nothing more I came up with.


Having problems proving $ \sum_{r=0}^{n}(r+1) \binom{n}{r} = (n+2)2^{n-1} $

I'm trying to prove the following  $$ \sum_{r=0}^{n}(r+1) \binom{n}{r} = (n+2)2^{n-1} $$  using the identity $$ \sum_{r=0}^{n} \binom{n}{r} = 2^{n} $$  but I'm not able to. This is what I did so far,   $$ \sum_{r=0}^{n}(r+1) \binom{n}{r} = (1) \binom{n}{0} + (2) \binom{n}{1} + ... + (n+1) \binom{n}{n} $$


Ubuntu 18.04 boot install error: Couldn't get size 0x800000000000000e

I installing Ubuntu to get a feel for it. On my old system it works fine, but right now I get a weird glitchy screen when I boot a USB stick / DVD drive / hard drive.    Couldn't get size 0x800000000000000e  If I turn up my volume after a bit of time when I clicked on either Install Ubuntu or Try Ubuntu without installing I hear the typical Ubuntu boot sound and I can blindly turn off my system, so I guess the error is just a graphical one.   I am Using right now:   OS: Windows 10   CPU: Intel i7-8700K 3.7   RAM: 16GB DDR4   motheroard: MSI H310M pro-M2 plus  GPU: Nvidia  RTX 2070    What I tried before was:   Boot from different media: USB stick, DVD, hard drive Do the same Stuff using Secure Boot (earlier I got another message "couldn't get db list", but that fixed itself after Secure Boot). Using different versions of Ubuntu, I only tried 16.04 and 19.10, but on each media.   I roamed through the forum for a few days now and honestly I can't find anyone experiencing this graphical issue like mine, so if you know of someone tell me then I will put down my request so there is no double posting.  I can't seem to enter anything like the GRUB menu or anything.


I had applied for a UK visitor visa and it got refused saying there were not enough funds and also they thought I would not be able to take care of my wife and child. I checked the mistakes and reapplied with more precise information and proof of funds.  The first time I had applied I got the reply in 10 days however this time it has already been 14 days and there is no reply. Only I got an email on 16 August, 2016 informing that it is reached British High Commission, Chennai.  Could anyone help me how much time will this take?  In the email they mention with 15 working days. August 18 was a holiday as it was Raksha Bandhan and also September 5. I wanted to know how much time could it take as i applied for Visitor Visa for 6 months and do i need to count 15 working from the day I got the email or from the next date ? Any help could be great.  My brother is in UK as he is a citizen so attached sponsorship letter too.


bash: adduser: command not found on centOS

I installed CentOS 5.5 on my VMWare 8 recently and I am trying to add a new user on the system. I am unable to add the user unless I use su - option. I believe it has to do something with path not set properly.  I updated the path and here is what it looks like  /usr/kerberos/sbin:/usr/kerberos/bin:/usr/local/bin:/usr/bin:/bin:/usr/X11R6/bin:/home/uone/bin:/sbin   I believe the command is in /sbin dir which is already a part of path. Can anyone suggest me what else I might be missing?


I have Googled and also checked Stack Overflow answers for this. But I am not able to understand clearly on this. Can anyone help explain simply the following example please?  function myObject(){     this.iAm = 'an object';     myObject.prototype.values = "value";     this.whatAmI = function(){         alert('I am ' + this.iAm);     } } var myObject1 = new myObject(); myObject1.values = "value2"; myObject1.iAm = "New";  alert(myObject1.values);   var myObject2 = new myObject(); alert(myObject1.values);   In the above code if I use this.iAm, it behaves in the same way prototype behaves.   I am new to Javascript Object Oriented Programming.   I expect many down votes. But I'm not concerned with that, because I just want to receive an explanation in a clear and simple way, that I have been able to find yet.


I have been reading all over the internet trying to solve this problem but I have not found a solution to my situation. I am running out of space on my ubuntu partition (dual-boot with windows 10) and I am trying to increase the size of it:    I have been trying from both ubuntu and windows. Now that I have created an unallocated partition (well, two) I thought I would just be able to increase the size by dragging it. But I am unable to change the size of the ubuntu partition, even decreasing it.   What can I do?


Ito Integral and brownian motion question

Can you prove directly from the definition of Ito integral (By that I mean limit of simple functions)   $$\int_{0}^{t}B(s)^{2} dB(s) = \frac{1}{3}B(t)^{3}-\int_{0}^{t} B(s) ds $$  So I started by writing $B(t)^{3} - B(0)^{3}= \sum_{0}^{n-1}B(s_{i+1})^{3}-B(s_{i})^{3}$ Where $0=s_{0}<s_{1}<...<s_{n}=t $ and $s_{i+1}-s_{i}$ tend to 0 as n tends to infinity. Where to go from here? Maybe bring in $(B(s_{i+1})-B(s_{i}))^{3}$.  Thanks!


How to export attribute table to Excel using ArcGIS Desktop?

In previous versions I could just export as a .DBF file, open it with Excel and then convert it to an Excel file. However, now in ArcGIS 9.3.1 the .DBF file can no longer be open by Excel. I have also tried saving as a text file but to no avail.


In the Academia SE, I can talk about academic professionalism, expectations, and advice. I'd like to know what SE site discusses similar topics related to careers/jobs. I have some questions I'd like to ask or research regarding answering certain questions in interviews, wording something on my resume, and getting endorsements.


Let's say I have a metal bar (which does not expand or contract at all) that's 1 light-second long which is connected to a block at the end. I am in space holding the other end of the bar. If I pull on the bar, what happens?  If the block moves instantly, then shouldn't the bar appear to get longer, because I don't see the end move until one second later?  On the other hand, if the block takes one second to move, does the bar actually expand, as my end has moved but the block's end hasn't?


I have done half an hour reading around to prepare to clone my hard drive.  It has multiple partitions, including a Windows partition.  I am going to buy a very large external hard drive for the backup.  I would like to be able to use this clone to restore the whole drive in case something goes wrong (I'm about to do some OS re-shuffling).  I want do learn how to do this using dd, as I like low-level tools that don't require installing anything.  I found the following useful code from the  (entered from a root shell using a live CD):  dd if=/dev/hda of=/dev/hdb & pid=$! while kill -USR1 $pid; do sleep 1; done   (I know that I will have to edit the input and output locations.)  However I have two questions.  The first one is very noobie: this command is split across two lines.  Surely when I press enter after the exclamation mark it will start the process?  Two, on other sites it recommended entering block size.  Like this:  # dd if=/dev/hda conv=sync,noerror bs=64K of=/mnt/sda1/hda.img   I don't know anything about block sizes.  Is 64K right?  It looks like my block size is 512 bytes from the following, the output of sudo fdisk -ul:  Disk /dev/sda: 750.2 GB, 750156374016 bytes 255 heads, 63 sectors/track, 91201 cylinders, total 1465149168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0xc3ffc3ff     Device Boot      Start         End      Blocks   Id  System /dev/sda1   *          63   143364059    71681998+   7  HPFS/NTFS/exFAT Partition 1 does not start on physical sector boundary. /dev/sda2       976867328  1465147391   244140032    7  HPFS/NTFS/exFAT /dev/sda3       143364094   976867327   416751617    5  Extended Partition 3 does not start on physical sector boundary. /dev/sda5       143364096   162895871     9765888   82  Linux swap / Solaris /dev/sda6       162897920   205864959    21483520   83  Linux /dev/sda7       205867008   976867327   385500160   83  Linux  Partition table entries are not in disk order  Disk /dev/mapper/cryptswap1: 10.0 GB, 10000269312 bytes 255 heads, 63 sectors/track, 1215 cylinders, total 19531776 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0x433bb3a7  Disk /dev/mapper/cryptswap1 doesn't contain a valid partition table   Thank you.


links are autocompleted on preview but not rendered when posted

Using question links conversion into links with titles, if you paste https://meta.stackexchange.com/q/350279/209901 in a post, then it gets converted into a proper link to that question: . Also, and according to  in , <s>bla</s> strikes the text in it: bla. However, I noticed that this does not work if within a <s> block of strikethrough without a space on both sides:  https://meta.stackexchange.com/q/350279/209901 (this is <s>https://meta.stackexchange.com/q/350279/209901</s>)     (this is <s> https://meta.stackexchange.com/q/350279/209901 </s>)   The funny thing is that it renders well in the preview:


How can i get better crop marks in InDesign CC that are simpler to cut?

I  know how to add regular crop marks to a design, my issue is when I go to cut out my prints on a paper cutter most of my crop marks are gone after 2 cuts so lining up the paper cutter gets really difficult. Is there any way to change the crop marks or an advanced crop mark script or something I can use on the latest version of InDesign?   I print out a number of labels and drawing lines on each one or using a knife to cut the inside out is kind of overkill. I remember someone turning the lines into a T (with a pen afterwards) so when you cut there are still lines inside you can use to guide you, just how would I do that in InDesign?  I sometimes do get me labels printed and would hate to have to make 2 versions just so i can print them myself. Would I really have to add in my own lines/custom crop marks in my document? Is there not enough people printing their own stuff to make a simpler solution?   (source: )


"I didn't know Ed was Welsh" or "I didn't know Ed is Welsh"?

I came across these two sentences and asked myself whether I could always use both versions:      I didn't know Ed was Welsh.   Did you know that Cliff's wife is Canadian?   Both relates to someone's nationality. I assume both people still live. So could I say I didn't know Ed is Welsh? Or as I know now - do I have to use the simple past (was) here?


Why is window glass only transparent from one directional axis?

If you look through a pane of common window glass the way it was meant to be looked through, it's clear.  But if you look at it from the side it's not very clear at all, but a dark green color.  One might think at first that this is due to thickness, that the glass is actually green (but highly translucent) throughout, but when looking straight through a pane it's thin enough that you don't notice the green color.  But if you pick up a small piece of a broken window, a shard no larger than the thickness of a window pane, you can still see that it's transparent from one direction but dark green when looked at from the side, so clearly (no pun intended) it has to do with some property of the glass itself and the angle at which it's looked through, rather than the thickness of the glass.  Can anyone explain why the same uniform material has a radically different color depending on which way the light travels through it on the way to your eyes?


How to pre-populate paragraphs when creating a page

I have tried for some time to find out a way to populate a new page with a few paragraphs to save time on most of the pages (but which might change position or even get dropped for some pages) but so far haven't found a way to do.  I think I have found out how to do the paragraph adding part, but what I am missing is how to fire the code when a new node of relevant content type is created.  I have tried hook THEME_node_create and THEME_node_insert, but they seem not to be fired when a new node is requested. I read that not all hooks are implemented for a theme but how then to achieve this functionality?   I probably (as most of the times) am missing something trivial, but please, help me find the light.  wbr  hank


Way to directly enter name of new created file

I installed Ubuntu 18.04 and I enabled the UI option for creating a new file(add file in Templates folder). But is there a way when click on 'New Document' (I named it in that way) to create file and focus you on its filename to directly edit it? Not I have to create file, click on it to rename it and then to enter the new name.  Thanks in advance!


I have a body in 3D-space and I would like to calculate the rotation axis when the body moves from A to B. I know the location (x, y and z) and the orientation (rx, ry and rz (axis angles)) at both A and B.  I have read about Rodriguez' rotation formula and know how to find the axis of rotation, but how can I incorporate the translation components as well?  Any help is appreciated!   /Daniel


When is the appropriate time to use "a" vs "an"?  For example, "I have a array of..." vs "I have an array of..."  I may be mistaken but I would typically use an in this case.   Firstly, am I correct to use an in this case? Secondly, is there a rule of thumb or grammatical rule that defines the appropriate usage? Lastly, If there is a grammatical rule, what is a recognized resource to its definition?


How to resolve a C++ template link error in XCode?

My template class compile successful but link error.   Error message: Undefined symbols for architecture x86_64:  "calculate<int>::plus(int, int)", referenced from: _main in main.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation)   Code is very simple: 1. calcualte.hpp  template <class T> class calculate {   public:     T plus(T a, T b); };   2. calculate.cpp  template <class T> T calculate<T>::plus(T a, T b) {    return a+b; }   3. main.cpp  calculate<int> cal;  int a = cal.plus(11,20);   If I move the code in calculate.cpp to calculate.hpp, it will build successful. It should be link configuration in XCode. Anyone can help?


How can I support different resolutions with Monogame?

I want to support the following 4 resolutions in my Windows Phone 8 game: 480 × 800, 768 × 1280, 720 × 1280, 1080 x 1920. How can I do that with Monogame? If I draw a sprite with Monogame, the sprite is not drawn on the right place in every resolution. For example, with a resolution of 768 × 1280, the sprite is drawn in the center of the screen, but if I use another resolution, the sprite is no more drawn in the center of the screen.  What should I do so that the sprite is in every resolution on the same place?


Given $\Sigma a_n$ diverges show that $\Sigma \frac{a_n}{1+a_n}$ diverges.

Intuitively speaking, I first thought that if the series $\Sigma a_n$ is divergent then  $$\lim_{n \to \infty} a_n \ne 0$$  therefore it was clear that $\Sigma \frac{a_n}{1+a_n} $ would be divergent, but when I thought about it there are cases where the limit of the sequence does approach to $0$ and yet diverge, like the harmonic series.  Then I tried to go with since the sequence diverges, the series is not Cauchy (I m not even 100% sure if this is true but I tried)  $$|\sum_{i = m}^{n} a_n| \gt \epsilon$$  and derive the other series to not be Cauchy as well, only to not being able to reach.  I appreciate all the help.


Can't spot the null exception in program

I want to pick a particular “short” word in an array of words, that is, words with at most three characters. For this example, if you are passed an array containing the strings  "Mary", "had", "a", "little", "lamb" and you are asked to return the second short word, you would return "a".  import java.util.*; public class Numbers {     String[] words = {"Mary", "had" , "a" , "little" , "lamb"};        int n = 2;        public String Numbers;        String[] word;        {           int counter = 1;           int length = 0;           int count = 0;            for (int i = 0; i < words.length; i++)           {              length = words[i].length();            if (length <= 3)            {               count++;               **word[count] = words[i];**            }           }           String answer = word[n];           System.out.println(answer);         }  }   When I run the code, it gives me a null exception error, and I'm not sure how to fix it.  The debugger told me it had to do something with the word[count] = words[i];  What is wrong with my code?