Duplicate icons on taskbar in IntelliJ – Windows 10

I have an issue with IntelliJ IDEA and Android Studio when I pin the icons to my taskbar. If I click on the icon, the actual window opens in a smaller duplicate icon on the taskbar rather than opening the window in the pinned icon.  I have tried uninstalling with Revo Uninstaller Pro and reinstalling, but to no avail. Copying the .exe file directly to the AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar folder doesn't work – the icon does not appear.  This is not a duplicate of this question:   I have tried all the suggested solutions from the earlier question, to check, but there is still a duplicate icon, so maybe it is a problem with Windows 10 specifically. I do not have any problems with any other programs.


Show that $A + B$ is bounded below and $\inf(A+B) = \inf(A) + \inf(B)$

Suppose that $A$ and $B$ are non-empty subsets of $\textbf{R}$ which are bounded below. Let $A+B = \{x\in\textbf{R}: x = a + b\,\,\text{for some}\,\,a\in A,b\in B\}$. Show that $A + B$ is bounded below and $$\inf(A+B) = \inf(A) + \inf(B)$$ What about products? MY (NEW) ATTEMPT If $a\in A$ and $b\in B$, then $a\geq\inf(A)$ and $b\geq\inf(B)$. Consequently, $a + b\geq\inf(A) + \inf(B)$, which means that the set $A + B$ is bounded below. Since it is not empty, it admits an infimum. We shall prove that $\inf(A + B) = \inf(A) + \inf(B)$. Given that $\inf(A) + \inf(B)$ is an lower bound to $A+B$, it results that $\inf(A) + \inf(B) \leq \inf(A + B) $. Let us assume by contradiction that $\inf(A + B) > \inf(A) + \inf(B)$. Then I get stuck. Could someone provide a solution based on contradiction? On the other hand, if we consider the set $AB = \{x\in\textbf{R}:x = ab\,\,\text{for some}\,\,a\in A,b\in B\}$, then $\inf(AB)\neq\inf(A)\inf(B)$ in general. Indeed, consider $A = [0,1]$ and $B = [-1,0]$. Then $\inf(AB) = -1$, $\inf(A) = 0$ and $\inf(B) = -1$. Thus $\inf(AB)\neq\inf(A)\inf(B)$. Could someone please verify if the wording of my proof is good enough? This question has already been asked  and , but I'd like to know if there is another approach to the first part.


There exists a Snail lineage . in each generation every snail, independent from the other: Dies at probability 1/3, Have a single offspring and then dies at probability 1/3 Have 2 offspring and then dies at probability 1/3  the lineage goes extinct if from the single offspring in generation 0 ,there are no remaining offspring in some generation i . what is the probability that the lineage goes extinct?  this is so confusing to me i cant even wrap my head around it to start, please help.


Limit of a Riemann sum $\lim_{n\to \infty} \frac{1^p+2^p+\ldots+n^p}{n^{p+1}}$

I have$$\lim_{n\to \infty} \frac{1^p+2^p+\ldots+n^p}{n^{p+1}}=$$ I managed to simplify it down to $$=\lim_{n\to \infty}\left( \left(\frac1n\right)^p \cdot \frac1n + \left(\frac2n\right)^p \cdot \frac1n + \ldots + \left(\frac{n}{n} \right)^p \cdot \frac1n \right)=$$ $$=\lim_{n\to \infty} \sum_{i=1}^{n} \left(\frac{i}{n}\right)^p \frac{1}n$$ How should I calculate this limit?


I'm  trying to make a website on my own, but i don't have a lot of pictures. Can anyone tell me a website with a lot of pictures of different styles like photography, flat design, etc...


Can private key used in ECDSA be discovered when many signatures were colleced?

Can private key used in ECDSA be discovered when many signatures of different messages were collected (1M+) or may signatures of the same message were collected? Will small nonce bias be easily exploitable?


Switching yum from RHEL to .. something else?

My various managers have decided that it's too expensive to keep paying for a subscription to the RedHat network for OS updates. Is it possible to switch to Fedora/CentOS or do I need to reinstall the OS to do this properly?  EDIT: Just found  duplicate. Oops.


id name books 1  dan  history,physics,english 2  ron  chem,social,biology 3  mon  it,ece,eee   I need an output as   id name books 1  dan  history 1  dan  physics 1  dan  english 2  ron  chem 2  ron  social 2  ron  biology 3  mon  it 3  mon  ece 3  mon  eee


I have two path one is "book/content/9(book_id)" render a View page and another is "book/content/book_alias" (autopath)   Now view get a argument 9 and display a View Page but when "book/content/book_alias" is requested display a node rather than node in View Page why this happen ? and how to solve this ?


Is the vacuum empty? Are virtual particles in the vacuum? Is the vacuum non-zero?

I have read a lot about this stuff.    Is the vacuum empty? How is it not-empty?    But nobody can it explain serious and simple that I can fully understand it.  Some physicists tell may that virtual particles were a big lie.    There don't arises in the vacuum?  What is the truth about the vacuum?   I found this:      Is the Universe a Vacuum Fluctuation?      EDWARD P. TRYON      1.Department of Physics and Astronomy, Hunter College of the City University of New York, New York, New York 10021      Top of page   Abstract      The author proposes a big bang model in which our Universe is a fluctuation of the vacuum, in the sense of quantum field theory. The model predicts a Universe which is homogeneous, isotropic and closed, and consists equally of matter and anti-matter. All these predictions are supported by, or consistent with, present observations.      Nature 246, 396-397 (14 December 1973) | doi:10.1038/246396a0    What does this paper tells us?  Is the vacuum empty or not?  Are virtual particles in the vacuum?  Can a universe arise from nothing?


In electrostatics, why the electric field inside a conductor is zero?

In electromagnetism books, such as Griffiths or the like, when they talk about the properties of conductors in case of electrostatics they say that the electric field inside a conductor is zero.  I have 2 questions:    We know that conductors (metallic) have free electrons which randomly moves in all directions, so how come we can talk about electrostatics which by definition means stationary charges? When the textbooks try to show why the electric field inside a conductor is zero they say let us put our conductor in an electric field. What happens then is that there will be an induced surface charge density which consequently induces an electric field within the conductor such that the total electric field within the conductor will be zero. That is perfectly understood, but my problem is the following: the original claim was that the electric field within a conductor is 0, not the electric field after putting the conductor in an external electric field it became zero. I do not understand the logic!


Why won't Windows 7 record crash details when the paging file is separated from the operating systems drive, and can I do something about this?

I've got a secondary harddrive (a separate physical device, not a logical partition) specifically dedicated for the Virtual Memory paging file.  The drive is 3.5x larger than my RAM, so it's plenty large.  When I configure Windows 7's virtual memory to put the paging file on this second harddrive and not the same drive as the operating system, I'm warned,     If you disable the paging file or set the initial size to less than 800 megabytes and a system error occurs, Windows might not record details that could help identify the problem. Do you want to continue?   So in other words, if I get a Blue Screen of Death, I won't be able to investigate why, just because I put my paging file at a more efficient location.  The best explanation I can find from searching the web is that Windows just doesn't want to make error dumps on a drive separate from the operating system location.  Can anybody give me a less nonsense explanation for this?  I don't want to have to tell Windows, "Sure, go ahead and continue managing a paging file on the primary drive," just so I can get a debug dump, as that totally defeats the purpose of a physically separated paging file.  Is there a workaround to having my paging file on a separate drive and still get error dumps?


What can I do about 99% disk usage (only 0.9 MB/s)?

My new laptop is two months old, the first day I got this laptop I noticed this but I assumed it was a bug in Windows 8. However I still have this issue today after reformatting and installing all updates.  The problem is that the disk shows 99% usage from an application...  In this case Dropbox, but the usage is never over 2 MB/s; in this case it is 0.8 MB/s.  What can I do about this?


Calculating the best approach speed to take a corner based on rotation speed

I am learning programming for computer games and it seems i am struggling to work out an equation for a steering behaviour.  I have a vehicle that navigates around objects. Some times it has to take a really sharp turn and so has to slow down before it approaches this turn to take it without over/under steering. It may even need to stop completely whilst its rotating (like a tank would).  I am wondering how you can calculate the best approach speed to take a given corner/angle.  I have 3 properties for the vehicle, a max speed, an acceleration (same for increasing and decreasing the speed) and a rotation speed.  Is there any general equation that can help with this that i can then try to translate into code.


Python/Cython on Windows, CString causing issues

AttributeError: 'CString' object has no attribute 'decode'  Scouring the internet doesn't find me much. AFAIK it seems to be part of Cython. Anyone who can point me in the right direction? Im also not getting much of a stack trace. (Inherited a fairly large django project)


I work in Thailand, can my employer by any means cancel my USA visa? Does the employer have that right ?  Visa on the passport of an employee is the property of an employee or employer ?


Best practice for saving Persistent Settings in C#

I have a C# WinForm that runs a batch file to flash a device through CMD.  I have a few variables (mostly file paths, but also a COM port # and a "setup" bool that drives a setup window if they're all unset) that are dependent on where the app was installed and what the port happens to be on that specific machine.  My initial thought process was to have a simple txt file that would have one of these on each line. I would stream read them in order at app startup and then decide to either run the app as normal, or first run a startup.  That said, there is a App.config already in my project, and I wondered if I would be better off using that, as I can't seem to include a txt file in my C# app the way I could in C++ and just refer to it.  Is one of these ways considered better than the other, or is it situational or just by choice? Or is there a better way I should be handling this that I haven't thought of?  I've never written a C# app to the point where I build it and set it up with an installer (there is a second program running in the background) so I'm a little lost with this - i'm not used to doing initial setup stuff as I do a lot of webapps which are all pretty persistent just by default or just write tools for myself and run them from within VB


An English idiom for "solve a problem that has been solved"?

In Polish, and I believe in a number of other European languages, there is an idiomatic expression which translates to "to force a door which is already open". It is used to describe a situation when much effort is spent on solving a problem which has already been solved, or did not exist in the first place. For example, if someone was doing research to answer a question which has already been answered, one would be said to be "forcing an open door". The same would apply to a person who is arguing a point that everyone already agrees with.  As far as I am aware, this phrase does not carry similar meaning in English. (Or does it?). Hence, I would like to know if there is an idiom with similar meaning? If not, is there a succinct way to describe such situations?


Adware changed file type of extensionless file

[Solution]The issue has been resolved. I ran the 'Advanced Renamer' program as suggested, and changed the file type of my make file from make to make.mak. Then after the program was done I removed the extension and it showed as type File. From then on, every extensionless file that I create has that type.  Recently my system (Windows 7) had become infected by some Adware. I removed its entries in the registry and deleted the relevant files in my Program Files and ProgramData folders. A few days later I was working on a coding project when I noticed my make file had a type that was the name of the adware program.  Here is an image of my make file in a folder:   I'm pretty sure that the adware is not active anymore. However, I'm not sure how I can change the file type of an extensionless file. How can I change the type back to the generic 'File' descriptor?  [Edit] I have attempted to use the suggested answers in the thread linked but HKEY_CLASSES_ROOT\Type was not present in my directory. I then tried to create a new key: HKEY_CLASSES_ROOT\..  This did not change the file assosiation back to 'File' unfortunately. So I removed the HKEY_CLASSES_ROOT\. key, but it didn't change the association either.  [Edit 2] To clarify on the extension: The image shown is already showing the file extension. That is to say, there is no file extension. I have the hide file extensions for known file types unchecked in the image and my make file has no extension. All extensionless files will show the file type 'AulleCheapPrice.'


How to get my actual data from ContentNote API in Salesforce using SOQL?

My Notes has Title-Task2 and Content is "Talk to customers"  When I run following query:  SELECT Title,Content FROM ContentNote  Output is:  ('Title', 'Task2'), ('Content','/services/data/v42.0/sobjects/ContentNote/0692x000000WFDKAA4/Content')])]  how to get my actual content from this?


which line feature connected to which two point feature?

i have point Feature (man hole) and line feature (cable). just i want to know which cable length is connected in between which two manhole. if i put spatial joint it will take only starting point or end point. i want know the both point.  Please revert me further clarification. i am new to the GIS Field. so please kindly help me out.


Prove $p\mid\frac{x^{a}-1}{x-1}$ using Fermat's little theorem

Fermat's little theorem states that if $p$ is a prime number, then for any integer $a$, the number $a^{p} − a $ is an integer multiple of $p$. In the notation of modular arithmetic, this is expressed as $a^{p} \equiv a \pmod p.$  Using this theorem prove:  Given a prime number $p$, show that if there are a positive integer $x$ and a prime number $a$ such that  $p$ divides  $\frac{x^{a}-1}{x-1}$, then either $a = p$ or $p \equiv 1 \pmod a$.  $$p\mid\frac{x^{a}-1}{x-1}$$  So, I'm thinking: $$\frac{x^{a}-1}{x-1} = x^{a-1}+x^{a-2}+...+1$$  I tried the telescoping technique but that doesn't work, assuming $a = p$, shows that $x^{p-1}\equiv 1 \pmod p$.  So, what else can I do?


prove that $\lim _{x \to \infty} x\sin x$ doesn't exist

i don't even know how to start.. just how we can turn choosen $\epsilon$ into $M$ so that we can find suitable $x$ if L is unknown ?


Prove there are no other solutions of functional equation $f(x+y) = \frac{f(x)+f(y)}{1-f(x)f(y)}$

I have the following functional equation. Find all continuous functions $f:(-1,1) \to \mathbb R$ such that $$ f(x+y)=\frac{f(x) + f(y)}{1 - f(x)f(y)} $$ The first obvious solution is $f(x) \equiv 0$. Another one I guessed, it is $f(x) = \pm \tan x$. I suspect, that there are no more solutions. The problem is that I don't know how to prove that.  Since we have a rational equation, I have no idea how to make any substitutions in order to get expression for $\tan x$ (as it is not a rational expression).  P.S. I can also show that it is true that (a) $f(0) = 0$ (take $x=y=0$), and (b) $f(-x) = -f(x)$ (take $y=-x$).  Update: there is a solution of this problem also here:


Solving inequality for convex functions.

A function $f : I \rightarrow \mathbb R$ on an interval $I$ is convex   if $f((1-t)x+ty)\le (1-t)f(x)+tf(y), \forall x,y \in I, t \in [0,1]$      Assume now that $I$ is an open interval.  Show that if $f$ is convex   then for each $c \in I$ there exists $m \in \mathbb R$ such that $m(x  − c) + f(c) \le f(x)$ for all $x \in I$ , and if in addition $f$ is   differentiable at $c$ then $f'(c)$ is the unique $m$ that works. In   general, must m be unique?   (we have previously shown that convex functions are continuous)  I think I'm missing the point of the question.  Surely, by the mean value theorem we can find some $y\in (x,c)$ such that $f'(y)=\frac{f(x)-f(c)}{x-c}$ setting $m=f'(y)$ we get $m=\frac{f(x)-f(c)}{x-c}, m(x-c)+f(c)=f(x)$ such an $m$ fits the inequality we're asked to show.  I also cannot see why $f'(c)$ would be the unique solution or why we would ever get a unique solution of the inequality at all for that matter.  Clearly I'm misunderstanding the question, so if someone could point out where I would appreciate that.  Thank you


Linear functional $f$ is continuous at $x_0=0$ if and only if $f$ is continuous $\forall x\in X$?

Let $f$ be a linear functional on a normed space $(X, \|\cdot\|)$. Prove that $f$ is continuous at $x_0=0$ if and only if $f$ is continuous at every $x\in X$.  I understand that the $\Leftarrow$ is trivial but what about the other way?


Showing that $\frac{n}{(n!)^{1/n}}$ is monotonically increasing

I would like to show that the sequence   $$\frac{n}{(n!)^{1/n}}$$   is monotonically increasing.    I know that this sequence is non-negative, and that it converges to $e$, but I am unable to show that it is increasing.


Prove that the norm of a linear transformation satisfies the inequality $\|Tx\| \leq M\|x\|$ for all $x$.

Proof.  Let $T$ be a bounded linear operator.  Then $$\|T\|=\sup_{x\neq 0}\frac{\|Tx\|}{\|x\|}$$  So $\|T\| \geq \frac{\|Tx\|}{\|x\|}$, that is, $\|T\|\cdot\|x\|\geq \|Tx\|$.  I'm not understand if I let $M=\|T\|$. Is this proof correct?


Fetching the last update time of a table in database

I need to find out the last update time (or last changed time) of a table in the database (i.e. the last time when data in a specific table is updated, deleted or inserted) for deciding whether a backup is needed or not. As per the MySQL/MariaDB manual, I have used the following SQL statement to get the last modified time of a table in the database:  SELECT update_time FROM information_schema.tables WHERE table_schema='my_db' and table_name='my_table'; -- For table named 'my_table' in database 'my_db'  Here's the problem: The value of the resultant update_time field is always returned NULL even though changes are made in the specified table. What's more unanticipated is that when I manually browse the tables table in the information_schema database, there are no entry of my_db and my_table in table_schema and table_name fields respectively, meaning that the activities are not logged. Can someone please help me solve this problem and explain me the reason behind it?  EDIT: This question is not a duplicate as the question also asks about the fields of information_schema.tables being NULL rather than just asking how to get last update time.


Looking for a big fantasy novel about scholarly monks that sort of worship math?

Earlier this year, I read a huge (1000+ pg) novel about a cloistered group of monks that sort of worshiped math. The story involved alternate dimensions or time travel or something. A big thing in the book was coordinates, containing data like for speed or something as an alternate axis. There were several rings of the monastery.   At some point the main character was called out of his monastery to never return. I'm hoping to figure out the name so I can discuss it with my book club.


Energy stored in a capacitor vs Work that the battery does

Say we have a battery at a fixed voltage of $V$ charging a capacitor with capacitance $C$.  When the capacitor is fully charged, the energy stored in it will be $\frac{1}{2}QV$, where $V$ is the final voltage of the capacitor (and the voltage of the battery).  However, I'm a little confused as to the work the battery does...  To me, it seems that if the battery pushed $Q$ onto the capacitor, and the voltage of the battery is $V$, it must've done $QV$ of work, which means that the energy stored in the capacitor only accounts for half of it.  Where did the rest of the work the battery did go?


Avidemux is no longer available in Ubuntu 18.04, what is an alternative?

The software avidemux seems to be no longer available in Ubuntu 18.04.  The command   sudo apt install avidemux   gives the prompt  Reading package lists... Done Building dependency tree        Reading state information... Done Package avidemux is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source  E: Package 'avidemux' has no installation candidate   So what is the GUI alternative of avidemux?


How to create new partitions for a linux system that contains Logical volumes

I am trying to add new partitions which are not logical volumes. But I have a system with logical volumes. I tried reducing the lv_home partition size using ‘lvresize’, and reduced a LV size by 5GB successfully. And I want to create new partition with that 5GB. But I am not able to find that space.  xvda 202:0 0 150G 0 disk  ├─xvda1 202:1 0 500M 0 part /boot  └─xvda2 202:2 0 149.5G 0 part     ├─VolGroup-lv_root (dm-0) 253:0 0 50G 0 lvm /     ├─VolGroup-lv_swap (dm-1) 253:1 0 3.9G 0 lvm [SWAP]     └─VolGroup-lv_home (dm-2) 253:2 0 90.6G 0 lvm /home   I reduced lv_home from 95 to 90GB. Now where this free space is available?. When I tried to make partion using "fdisk xvda" it says no free sectors. I want to create 2 or 3 partitions using that 5GB. Would some one help me in doing that?


Task manager view   Process explorer view    Process thread details    I have noticed over the past weeks, that my system thread in task manager is always around 10%, which wasn't the case before.  Exploring the task in Process explorer showed something to do with  ntoskrnl.exe!DbgSetDebugFilterState+0x20 but searching on google for those things didn't come up with answers.   I don't know if some OS expert can give advice on what happened here?     UPDATE I went through the linked question and was able to install the Windows SDK for analyzing the performance, but even with the logs and analysis I couldn't find a specific culprit.     Eventually I was able to resolve the issue by disabling the page file first, and then setting custom size from 9GB to 100MB - 1GB.  This seems to have eliminated the kernel pagefile manipulation that would keep going on. I hope this is the correct culprit.


Let ${A}$ be a $2 \times 2$ matrix. For every two-dimensional vector ${v}$, there...

Let ${A}$ be a $2 \times 2$ matrix. For every two-dimensional vector ${v}$, there exists a two-dimensional vector ${w}$ such that Aw = v. Show that ${A}$ is invertible.  I'm not sure how to do this.


Print application version using terminal

Just out of curiosity, Is there any terminal command that prints out the version number of any application that is installed? For example, the version number of wine?


Is $\frac{\partial}{\partial x_1}=\frac{\partial}{\partial y_1}$ if $x_1=y_1$?

Let $M$ be a manifold, $p\in M$ and $(U,\varphi=(x_1,\dots,x_n))$, $(V,\psi=(y_1,\dots,y_n))$ two local charts such that $p\in U\cap V$ and $x_1=y_1$. Is it true that $(\frac{\partial}{\partial x_1})_p=(\frac{\partial}{\partial y_1})_p$?  My professor says that the answer is yes, and so I build a proof. But then I found the following counterexample:  Let $M=\mathbb{R}^2$, $p=(0,0)$, $U=V=\mathbb{R}^2$, $\varphi(u,v)=(u,v)$ and $\psi(u,v)=(u,u+v)$. Then $x_1(y_1,y_2)=y_1$ and $x_2(y_1,y_2)=y_2-y_1$. Using the formula for the change of basis I've got  $$(\frac{\partial}{\partial y_1})_p=\sum_{i=1}^2(\frac{\partial x_i}{\partial y_1})_p(\frac{\partial}{\partial x_i})_p=(\frac{\partial}{\partial x_2})_p-(\frac{\partial}{\partial x_1})_p\neq (\frac{\partial}{\partial x_1})_p$$  What's wrong with this counterexample?


I want to program somthing using opengl es , i search software center for anything related and i found libgles1-mesa-dev , then i wrote a simple main program and included :    #include <GLES/gl.h>   #include <GLES/glext.h>     and it compiles , but if i try to use an opengl es function it says undefined reference . (meaning the include without using functions compiles , but after writing a function it gives that error)    i compiled using simple    gcc ./*.c -o xxx     how can i use this library to program opengl es 1.x ? or opengl es in general ?


On the search result page if you exclude tags in filter, for example, , there is not translated word "not".         I didn't find this string neither in Transifex nor in traducir. Could you add it? So we will be able to translate this string.  Related discussion on SOru: .


Definite article "the" with places/buildings

Could you tell if this is correct? Why sometimes the names of schools, museums and churches have the definite article while the others have not?     Kazimierz Wielki Primary School in Przedbórz       John Paul II Junior High School in Przedbórz      Folk Museum in Przedbórz      Church of Saint Alex in Przedbórz   Should I use "the" before the names? There is no "official name" in these cases (I mean whether is with "the" or not). What would you use? I know that with "of" phrases the article "the" is used but I also found a confusing case: In wikipedia there is the name:      the Johns Hopkins University   but on their website there is:      Johns Hopkins University   Could you explain this?


trace part of an image, extrude into 3d object?

I have a logo it's an image of earth and around it are arrows, I would like to trace a plane along those arrows please   if there's any special instructions to extruding it please let me know


SFDX Can't Pull Source from Scratch Org "Metadata API received improper input" AppMenu and AppSwitcher

I'm using SFDX and I made a change to the visibility of my app in my scratch org but when I try to pull the changes down (sfdx force:source:pull) I get:     ERROR:  Metadata API received improper input. Please ensure file name and capitalization is correct. Load of metadata from db failed for metadata of type:AppMenu and file name:AppSwitcher.   Has anyone seen this error or know of a fix?


My fiance left me and married her ex husband 2 months later. We had two financed vehicles. Both in our name. One got repossesed. She took the other one with her.   My questions are: How can I get my name off the title and loan? Is bankruptcy the only way? Can I sue? Am I supposed to be listed on their insurance?   I cant get a car loan because of this. Thanks


Spaceship crew loses piece of equipment, lies about it, causes all other spaceships to be grounded

Years ago I read a short story about a spaceship crew who were reviewing a checklist of equipment but couldn't figure out what one of the items was supposed to be (it was some sort of abbreviation). It was a military spaceship, so inspectors were used to make sure that no equipment was lost (and it would be a huge problem for them if they had to tell the inspector that they "lost" this item).  Rather than admit they couldn't find this piece of equipment they devised a scheme to report it as destroyed, and then they would be issued a new one and figure out what it was. They claimed it was destroyed in an FTL jump (or something similar). When this was reported, the high command immediately ordered all other spaceships grounded until the cause could be determined.  The reveal turned out to be that the item they were missing was      the ship's dog, who of course was perfectly fine and had been on the ship the whole time. They didn't realize it was the dog because the checklist item used an abbreviation. The high command ordered all ships grounded because they were concerned that there was a problem with the FTL technology that would harm dogs and humans.   I believe the story was written several decades ago, perhaps in the 70s or so. I think the author is fairly well known.  What is the title of this short story?


SharePoint 2013: Get multiple UserProfile with REST API

There are over 10000 User Profiles.   So I want to get all user Profiles in single request with all user properties.   Is it possible to get multiple users in single request matching particular criteria?  I need to know what will be the best approach from the performance point of view? It can't afford to be slower.  Please suggest something.


How can I build a custom distribution for running a simple web browser?

We are assembling some lightweight machines with the express purpose of displaying a single web page over a large screen. I need the machine to essentially boot up as lightweight and as quickly as possible and essentially have it run a browser (WebKit?) in full screen, loading one page which will be controlled dynamically by JavaScript. I'll be using an Intel D525 dual-core processor with integrated GPU, so I shouldn't need to set up any proprietary graphics drivers. Once I get one of these machines set up properly, I should just be able to dd the hard drive onto my computer and then dump it onto each new machine.  I have the following questions:   How can I create a "distribution" which includes only what I need? I suppose I'll need the kernel (;]), X, and a web browser of some sort, but not really too much else. Could I take something like Ubuntu Server and simply install X Server and find a way to have the machine automatically log in, start X, and start the web browser, no questions asked? Is there a book I can read or an article or something?  What can I use for a nice, stripped-down web browser that essentially runs a "chromeless Chromium?" These machines won't be accepting user input at all. If I need to manage them, I'll use SSH.


I have read so many questions and answers on this but none of them seem to fix my problem. Basically I have an HTML and CSS slideshow and I am trying to center this slideshow. I have position: absolute in the code, however when I try to remove that, the images are no longer in a slideshow and are just all down the page.   Here is my code:


Are Spellcasting Focuses inherently magical?

Im having a bit of a quarrel with my DM about if spellcasting focuses are magical. He believes that they are magical since it seems magical to him that you now dont need actual material components since your holding one, but I counter with  that no where does it state they are magical and that they are just a conduit for your magical power to come out. I have looked around on the internet a bit but have found nothing about it, does anyone know a definitive answer to this?


Random but very interesting probability question!

There are 100 types of cards, each type with a number from 1 to 100 on it. Each minute I am given a random card. Random means that the number of my card has an equal chance of being 1,2,3,...,100. I stop when I have cards of each number, that is, I stop collecting once I have each number on at least one card. How many minutes is this process expected to take? That is, find the expected value of the number of minutes I have to wait.  E.g. I could potentially get duplicates so this method will take a lot more than 100 minutes. Once I get 99 different cards, I will stop as soon as I get the other one which I haven't got yet.  Thanks for helping everyone!


I have used the below query with a constraint to check the values which are inserting to the stu_code column start with 's'.  mysql> CREATE TABLE student_info(        no INT(3) PRIMARY KEY,        stu_code VARCHAR(10),        CHECK (stu_code like 's%'));  Query OK, 0 rows affected (2.68 sec)   but it does not work. When I inserting the values (like below) I can insert values which are not starting with 's'.  mysql> INSERT INTO student_info VALUES (1,'k001'); Query OK, 1 rows affected (0.47 sec)   I am beginer with SQL, Can anyone help me find out what is the issue?


What are the fonts / template used by Foreign Affairs in this document?

Apologies if this is not the right forum to ask this question.  I'm astonished with how beautiful this document is: .  I was hoping somebody could give me their best guess as to the font of the following:   The Foreign Affairs logo Each of the fonts used in the title, subtitle, author name, and Volume Number Body text   Is there a template that is widely available that would allow me to recreate this?


Is there a function $f:\mathbb N \to \mathbb N$ such that $\forall n \in \mathbb N, f(f(n))=n+2015$ ?   Here's what I've done:  Assuming such a function exists,   $f(f(f(n)))=f(\color{red}{f(f(n))})=f(n+2015)=\color{red}{f(f(}f(n)\color{red}{))}=f(n)+2015$.  Hence $\forall n, f(n+2015)=f(n)+2015$.  A simple induction yields $\forall n,\forall k, f(n+2015k)=f(n)+2015k$.  This means that $f(n) \operatorname{mod}2015$ only depends on $n \operatorname{mod}2015$.  What then ? I can't reach a contradiction from here.


My suggestion is to add a Stack Exchange website for cryptocurrencies in general. There is just a Bitcoin website, but I have questions about cryptocurrencies in general. Maybe back when that website was started, Bitcoin was the only popular cryptocurrency, but now cryptocurrencies like Litecoin and Dogecoin are gaining popularity and they should be represented here as well. Is there a place to ask about non-Bitcoin cryptocurrencies, or would I need to propose a new site for it?


How can I calculate the affect of cooking my food on its nutrition

If I look on nutritiondata.self.com for the nutrition value of raw lentils (as an example), it tells me the . However, 1 cup of boiled lentils is good for !   I looked up the question, however the popular answer is that . But judging by those numbers, I think that it does!   So, what should I do?  Lentils being just an example! This applies to other foods too..


any help/explanation is appreciated (i know this is such a newb question but nonetheless)  when I try to "sudo apt update" the command fails on one "link" (Failed to fetch   403  Forbidden [IP: 143.95.32.90 80] )  why is that? did the apt update command complete successfully? does this have anything to do with updating repositories in /etc/apt/sources.list?  Thank you in advance for any help folks, greatly appreciate any feedback.


If we live not in 3 dimensional space but in 4 dimensional space time, then, why can't we "see" the fourth dimension? Shouldn't I see time like any other spatial dimension? Instead, I perceive it to be as flowing.   How is time fundamentally different from space in this sense?


Confusion about Length Contraction (ex in Muon decay)

I am a bit confused about the implications of length contractions;   For example, in the muon decay problem, we assume that the distance between the muon and the earth is contracted only in the frame of reference of the muon (I've heard justification saying this is because it is Earth's atmosphere) but suppose there were no atmosphere then in the reference frame of Earth shouldn't the length between them also be contracted?  What I don't get is if one object is moving at a speed relative to another object, shouldn't this movement affect the distance between them in the reference frames of both of them, since their movement is merely relative?


There is a command   if [ -f ~/.bashrc ]; then     . ~/.bashrc    I need to know why there is "." right before ~/.bashrc?


Is this workaround used by my book to find the value of $1/0$ legitimate?

I was doing a physics problem and found that I reached an interesting equation:   To cross the river directly from A to B (making a right angle with the velocity of the stream), how must the fisherman direct his/her boat's motion? Find the angle ($\alpha$) between the velocity vector of the stream and the velocity vector of the boat. The magnitude of the velocity of the boat is $v=2.778\mathrm{ms}^{-1}$ and that of the stream is $u=1.3889\mathrm{ms}^{-1}$.  Solution: We know from the : $$\tan\theta=\frac{Q\sin\alpha}{P+Q\cos\alpha}$$ Similarly, $$\tan(90^{\circ})=\frac{u\sin\alpha}{v+u\cos\alpha}$$ $$\implies\frac{\sin(90^{\circ})}{\cos(90^{\circ})}=\frac{u\sin\alpha}{v+u\cos\alpha}$$ $$\implies \frac{1}{0}=\frac{u\sin\alpha}{v+u\cos\alpha}$$ $$\implies{v+u\cos\alpha}=0$$ Now, isn't $\;\dfrac10\;$ undefined? How is cross-multiplication valid here? I'm very confused.


Is it "are" or "is" when the noun is plural after a gerund?

Playing shooting games are/is my forte.      Watching movies is/are fun.      Reading books is or are good for you.   Do we use is or are for these sentences?


How do I take off body armor in GTA V online?

I am sick of the Armor, and I want to wear a purple shirt. In my attempts to remove the armor I have used the select option, gone into stores, and went into my wardrobe. How do I take the armor off?


Not sure how to go about solving this integral

$\displaystyle \int \left( \frac{1}{x^2+3} \right)\; dx$  I've let $u=x^2+3$ but can't seem to get the right answer.  Really not sure what to do.


how to change "§" (section symbol) key to write "`" (back quote)

I'm using back quote many times but never use the '§' symbol.  I'd like to change the key to always write back quote instead. does anyone know how can I change it programtically?


Determining convergence of divergence with justification: $\sum\limits_{n=1}^\infty\left(\sqrt[n]{n}-1\right)$

So I was asked to determine and justify the convergence or divergence of $$\sum_{n=1}^\infty\left(\sqrt[n]{n}-1\right)$$ and I think it diverges and was trying to use the Comparison Test by finding a function less than it that diverges but I am not sure what the function would be...  Thanks in advance for any help!


When you cook spaghetti, do you add olive oil to the boiling water?

Many people (at least in Germany) think that Italians add olive oil to the boiling water for spaghetti. However, Italians tend to tell the opposite (from my experience).  So, can you please state objective reasons for or against adding olive oil to the boiling water for spaghetti?


Im trying to prove that if $f\colon \mathbb{R}\to\mathbb{R}$ such that for all $x,y\in\mathbb{R}$ we have $\lvert f(x)-f(y)\rvert \leq (x-y)^2$ then $f$ is constant.  I have shown that if $f$ is differentiable, then the statement is true. But without the differentiability condition, I'm having a hard time.


Automatically (re)classify data from layer using QGIS?

Is it possible to automatically (re)classify the data of a layer? (properties-symbology-delete all-classify) Because now I have to do this manually each time my data source changes.


$\lim_{x\to \infty}e^{-x^2}\int_x^{x+1/x}e^{t^2}dt$  This is problem from Spivak calculus 1994, chapter 18, 31.  The book gives following solution: simply apply Lhopitatal rule, but what puzzles me is the way numerator is differentiated.   So they got $e^{(x+1/x)^2}-e^{x^2}\over 2xe^{x^2}$  But I think it should be  $(1- 1/x^2) e^{(x+1/x)^2}-e^{x^2}\over 2xe^{x^2}$ . I think they are missing derivative of $x+1/x$. Am I wright or wrong?  P.S Could anyone please help me editing this question?


What information does stock Android send to Google by default, and how do I opt-out?

I'm about to buy my first Android phone. My understanding is that, in order to download apps and get updates from Google Play, I need to be permanently signed into a Google account that's linked to my name via credit card information.  I find Google's  too ambiguous to understand what data is logged from Android users. I don't want to share more information than the device needs to operate.  Here are some steps I plan to take already:    Don't use Gmail Use a non-stock browser Use DuckDuckGo for search   My questions:   What other information does Android send to Google by default? What actions should I take to minimise data collection from Google and other apps? (I'll be using stock Android 4.2 on a Nexus 4.) Is Android still a good choice if I don't plan to use Google's services?


extend mounted Ubuntu drive with unallocated space

I have installed two operating systems i.e. WINDOWS 10 and UBUNTU 16.04.  Windows 10 C: drive (shows /dev/sda5 in GParted) is 130GB whereas accidentally, Ubuntu 16.04 drive (shows /dev/sda2 in GParted under extended which is mounted) is 9.59GB and giving me no free space available which is a headache for me.  I have freed 90.66GB from Windows 10 drive (it had became 130GB) and I make it unallocated. Now, I wanted to MERGE it with Ubuntu drive but Ubuntu drive is mounted and the unallocated space tends to merge in C: drive instead of the Ubuntu drive.    Note: I have tried every possible solution but all in vain. I have tried using GParted in Ubuntu and Disk Management and Easeus Partition Master in Windows 10. In GParted, I can create standalone drive and also can merge in the C: drive but cannot merge in Ubuntu drive. Same happens for the Windows 10 softwares.


I have a process creating the following files, which share a similar pattern.  file_1.txt file_2.txt . . . file_1000.txt . . . file_1901.txt file_1902.txt   But, there are only 1890 files in the folder. I would like to know if there is a way to identify the missing files from the list of files sharing a pattern.


Scaling vs Offsetting in Quasi-Poisson GLM

I  modeled insurance claim frequency assuming a Quasi-Poisson distribution in R. My frequency dependent variable was calculated, in advance of modeling, as the number of claims per underlying exposure. Someone  that it would be incorrect to do this, and that the correct method was to model the observed claim counts and use the underlying exposure as an offset.   Can someone explain the theoretical and practical differences between scaling and offsetting? I ran the code both ways and noticed that the deviance residuals are significantly smaller when using offsets, but otherwise there were no material differences in variable selection.   P.S. Note the similar but still different question .


List.contains() not returning correct result, but manual search does

I have a strange issue happening with my code below:    RestAPIHeader requestedBy = new RestAPIHeader("X-Requested-By", "test");    // Act   RestAPIRequest req = prepareLoginRequest(USER_NAME, PASSWORD);    // The following returns a list of header objects such that one of them   // is "X-Requested-By: test"   List<RestAPIHeader> headers = req.getAllHeaders();    boolean foundRequestedBy = false;   for (RestAPIHeader h : headers) {       Log.d(LOGTAG, "Header: " + h.toString());       if (requestedBy.equals(h)) {           foundRequestedBy = true;       }   }    // Assert   assertNotNull(req);    // This assertion passes   assertTrue(foundRequestedBy);    // This assertion fails   assertTrue(headers.contains(requestedBy));   What bothers me is that it seems like headers.contains(requestedBy) should be equivalent to foundRequestedBy in this code (since this is the result of a simple search). However, as I mention in the comments, it doesn't actually return the same value. It almost seems as though contains isn't using equals(), but rather ==. Can someone point out why this is the case?  Edit:  The equals method of the RestAPIHeader class is as follows:    public boolean equals(RestAPIHeader aOther) {     return mPropertyName.equals(aOther.getHeaderName())       && mPropertyValue.equals(aOther.getHeaderValue());   }


I have an upload script that I need to check the file extension, then run separate functions based on that file extension.  Does anybody know what code I should use?  if (FILE EXTENSION == ???) { FUNCTION1 } else if { FUNCTION2 }


Expiration of passport one month after leaving Canada

Can I travel to Canada end of March to 4 April 2019 if my visa expires with my passport on 29 May 2019


As you can see on the pictures below Area51 top bar popup contains narrow strings in some cases:  Site switch:        Reputation change:


Why do we assume electromagnetic fields to be doubly differentiable?

It seems like the identities of curl of gradient, divergence of curl, and the simple derivations of electromagnetic waves from Maxwell equations all rely on the symmetry (interchangeability of their order) of partial derivatives.  But mathematically speaking, this tacitly assumes that the electric/magnetic fields in question are continuously double differentiable, something which needs justification.  Why do we assume that in the real world, the fields are smooth enough for the identities to work, atleast almost everywhere?


Proof that if $(X,d)$ is a metric space and $\forall f:X\to \Bbb R, (f\text{ continuous} \implies f \text{ is bounded})$ then $X$ is compact

Is my proof of this correct? We will prove the contrapositive, that if $X$ is not compact there exists a continuous real valued function on $X$ that is unbounded. Since $X$ is not compact, there exists a sequence with no convergent subsequence. Consider such a sequence, $a_n$. Because $X$ is a metric space, $X$ is Hausdorff, and the sequence $a_n$ does not have an accumulation point lest it would have a convergent subsequence, so for each $a_n$ we can construct $B_{\epsilon_n}(a_n)$ such that each ball is disjoint. Now define $$f(x) = \begin{cases} 0 & x \not \in B_{\epsilon_n}(a_n)\\ n - n\frac{d(x, a_n)}{\epsilon_n} & x \in B_{\epsilon_n}(a_n)\\ \end{cases}$$ $f(x)$ is unbounded as $f(a_n) \rightarrow \infty$ as $n \rightarrow \infty$. $f(x)$ is also continuous by the pasting lemma as it is continuous on the closure of $\cup_{n=1}^{\infty} B_{\epsilon_n}(a_n)$ and the complement of $\cup_{n=1}^{\infty} B_{\epsilon_n}(a_n)$, which are both closed sets which union to $X$. Therefore $f(x)$ is continuous on $X$. So we have shown that if $X$ is not compact, there exists a continuous real valued function on $X$ that is unbounded, which is the contrapositive of the statement we were to prove.


I have copied some data into Excel 2010. I have found that some of the cells need to be widened to allow the data to fit. How do I automatically adjust the height of the cells to fit the content?


Please check the image, on my profile the CSS in the datepicker is gone - I'm using the latest version of Chrome.


Rearranging the alternating harmonic series and finding differences in its sum

I am to prove that if $$1-1/2+1/3-1/4+1/5-1/6+...=s$$ that $$1-1/2+1/3+1/5-1/4+1/7+1/9-1/6+...=3s/2$$    My approach:  $s/2=1/2-1/4+1/6-1/8+1/10-1/12...$ so that  $s+s/2=3s/2=1-(1/2-1/2)+1/3-(1/4+1/4)+1/5-(1/6-1/6)...=$ $1+1/3-1/2+1/5...$    This sort of leads to what I want to approach, but the terms are not quite in the right order. I assume I may not change the order of the last set of terms for it to match what I'm looking for. Any other suggestions?


Pearson correlation of data sets with possibly zero standard deviation?

I am having a problem computing the pearson correlation coefficient of data sets with possibly zero standard deviation (i.e. all data has the same value).  Suppose that I have the following two data sets:  float x[] = {2, 2, 2, 3, 2}; float y[] = {2, 2, 2, 2, 2};   The correlation coefficient "r", would be computed using the following equation:  float r = covariance(x, y) / (std_dev(x) * std_dev(y));   However, because all data in data set "y" has the same value, the standard deviation std_dev(y) would be zero and "r" would be undefined.  Is there any solution for this problem? Or should I use other methods to measure data relationship in this case?


What are the advantages and disadvantages of zoom lenses with a wide range of focal lengths?

Are there some disadvantages of a zoom-lens with wide range focal length compare to a lens with narrow range both having the same max. aperture?  For example, if we have two lenses:   Sigma 18-55mm f4 Sigma 18-300mm f4   Does the second lens have some advantages, except zoom, of course?  I mean when producers of camera lenses try to stow a wide range of focal length in one lens, does it affect the quality?


How to enable Synaptics Touchpad While Typing (without disabling palmcheck)?

All of the solutions to enable pressing a key while dragging the mouse involve disabling palmcheck. The problem is that palmcheck is extremely helpful. Is there a hack to keep palmcheck enabled and at the same time allow me to use the keyboard? This seemed to work for me on Windows 7, but when I upgraded to 8 and installed the latest synaptics drivers it became one or the other.


Does a body always rotate purely about its center of mass?

For example : A rod is held stationary in vertical position on a smooth horizontal ground and then released.  Now the center of mass has velocity and acceleration and every point of the rod has some acceleration and velocity which are different from center of mass'. How can one prove that the rod is rotatating purely about centre of mass?


Can I connect to a sandbox using JWT Flow and Prod connect app?

I'm trying to connect to a sandbox using the sfdx cli and the JWT flow through force:auth:jwt:grant. According to , we can use the same connected app information from Production to connect to our Scratch Org.  Is it something that should work for sandbox too ? I'm getting a "Failed: Not approved" error.  Connected app in sandbox comes from the refresh but has a different consumer key. The Permission set is set correctly on my user.  Is there a way to connect to a recently refreshed sandbox using the JWT flow (without manually changing something like the consumer key) ?


$x_n$ is the $n$'th positive solution to $x=\tan(x)$. Find $\lim_{n\to\infty}\left(x_n-x_{n-1}\right)$.


In Ubuntu 15.04, boot-repair running forever, trying to fix the system after deleting all kernels

I have deleted all my kernels.  I am trying to fix the problem with  from live USB  I have LVM enabled    How can I fix this?


I apologize for the dumb question but is the dx (or dy or similar) used in calculus a multiplier? I don't have a good grasp on what it really means or why it's there.  I'm getting to the point in integration where we are converting dx to du and it's weird for me to manipulate it like this.  An ELIF answer would be nice if that's even possible!


How can I tell, from the command line, whether the machine requires a reboot?

When you install certain updates (e.g. a new kernel) in Ubuntu Desktop, you get an indication that a reboot is required (in Lucid, the logout icon turns red).  How can I check, from the command line, whether an Ubuntu server requires a reboot?  I could grep for 'System restart required' in /etc/motd, but I'd like a solution that's more elegant.  Also, I want a solution that works in older releases, e.g. Hardy (8.04 LTS).


Existence of a Pivot Point in Euclidean Geometry

In geometry there is a term called a pivot point. There exists a pivot point 'P' in the interior of a convex polyhedron in a euclidean space if and only if every single line through 'P' contains exactly zero or two vertices of the polyhedron.  I asked one of my professors, but he gave me a very narrow example of a cube, but I want to know the maximum number of pivot points that exist in a polyhedron. Can someone please help me prove how many exist?


I'd like to be able to install packages for PyMOL like  and to do so I understand I need to know where it is installed (i.e., the file directory). I installed it using Ubuntu Software Centre.


What is the sorting rule for a user's list of network accounts?

The page I'm talking about is the Accounts tab in the Network Profile, example . The primary sort key seems fairly clearly "reputation," descending. However, secondary sort keys don't seem obvious. What I would expect is that:  If two accounts have equal reputation, question count, answer count, the one with more badges (perhaps gold, silver, bronze in that order) would appear higher in the list. If two accounts have the same reputation and badge counts and answer count, the one with more questions should appear higher in the list. If two accounts have the same reputation and badge counts and question count, the one with more answers should appear higher in the list. If two accounts have the same reputation, badge counts, question and answer count, the one most recently visited should appear higher in the list. (?) If two accounts have the same reputation, badge counts, question and answer count, and visit recency, the older account should appear higher in the list. (?) If two accounts have the same reputation, badge counts, question and answer count, visit recency, and age, they should be in alphabetical order. (?)  Currently, "" seems to be the "actual" current state unless I'm missing a pattern. Why not add additional sort criteria to the list creation, to more easily sort by level of activity descending? Also, I'll make this one more of a feature request for additional sort levels than  which asks more about the current state of the art, so as to help distinguish the two.


Error Measures, why is the sum halved? why not use the absolute value?

In a neural network class I'm taking the error measure is defined as:    If the purpose of squaring the difference of the predicted and target values is to always have a positive value, then why not just use the absolute value of the difference instead?  Secondly, why is the summation halved?


eBay buyer wants to send me $700 for shipping to Malaysia - Scam

I recently received the :     Hello!   I want to buy your 1080 ti and to be ship to my store in malaysia I will offer you the amount listed plus the shipment charges $700 all together also if there is more of it or any brand let me know. And payment via my PayPal, text me back on my business line if the item is still available ( 908.__455.__8461 ) waiting to hear back from you soon. so i can pay-in your funds thanks   Santos.   Don't worry, I am certainlly not accepting this offer.  Despite the incredibly sketchy-looking overall appearance of this message, the account that sent this is brand new, and has no feedback whatsoever. That, and the offer is simply far too good to be true makes me almost 100% certain that this offer is NOT legitimate.   Even if the sender did have an electronics store in Malaysia, there is no possible way to make a profit here buying the card I have listed and reselling it. (I assure you that a used 1080 Ti is not worth anywhere close to $1,210).  In plenty of other examples of scams on this site, when someone offers you a large amount of money to cover a supposed delivery cost, they will pretend they overpaid and request a portion of it back via a non-refunable means (pre-paid gift cards, Western Union, etc). However, since the transaction would take place using eBay through PayPal, wouldn't ebay's dispute resolution process prevent the buyer from simply being able to dispute the PayPal charge and get their $700 back?  I did notice though that the message is blatantly trying to get me to arrange the sale outside of ebay (seriously... who writes a phone number in such an awkward and obviously filter-circumventing manner?)  Perhaps ebay's ordinary systems would prevent this scam from working, and that is why the buyer wants to be contacted directly?  How is this scam supposed to work?


Could anyone help me with c#, please! If I have: bool x = true;  bool y = true; string temp = "x & y" ; bool myBo = temp; // my intention is myBo = x & y;  = true from the string  Is it possible to do that? Thanks


I am trying to solve exercise 1.1 in Neural Networks for Pattern Recognition by Bishop.  They give the gamma function as:  $\int_{0}^{\infty} u^{x-1}e^{-u} du$  I can only solve it using the form of the gamma function:  $2 \int_{0}^{\infty} u^{2x-1}e^{-u^2} du$   Which is equation 3   It is very unclear to me how these two forms of the gamma function are equal. Is there a well-known proof?


How do I get started with the google io mission dashboard?

Google released a new online game at    And it appears as if the first step is determining the cluster name, but I can't figure out how to determine the cluster name.  I've tried typing in random strings found around the console, and pieces of various satellite properties, but I'm stuck.  I would prefer not just knowing the answer, but how I'm supposed to figure it out. Is there a help option I'm not reading? Is this supposed to be some deep hacking of the javascript (it appears to be sending data to a server to be validated, so I don't think source loading will help.)


I'm working on a proof of AM-GM inequality, but for now I would like to prove more basic propositions.      Prove that the arithmetic-geometric mean inequality holds for lists of   numbers of length $2$. In other words, prove that for all positive   real numbers $a$ and $b$   $$\frac{a+b}{2}≥\sqrt{ab}$$   My attempt:  We know that $(a-b)^2 ≥ 0 $  Expanding  $$a^2 - 2ab + b^2 ≥ 0$$  Adding $4ab$ to both sides  $$a^2 + 2ab + b^2 ≥ 4ab \implies $$ $$(a+b)^2 ≥ 4ab \implies $$ $$a+b ≥ 2\sqrt{ab} \implies $$ $$\frac{a+b}{2} ≥ \sqrt{ab}$$  $\Box$  Is it correct?


This is straight from an exam question: Find the order of the permutation $(1465732)(358)(79)$ in $S_9$  So I understand that I first have to write this permutation in disjoint cycle notation, but I'm having trouble doing so. For example if you look at 3, (going from right to left) we have  $ 3 \to 5 $, $ 5\to 7$ so in effect $3 \to 7$  But then we also have from the first cycle $3 \to 2$?  So where is 3 actually sent by this composition of permutations? Thanks.


Why is this code using class variables not working as it would in Java?

I am moving from Java to Python. In Java, Static variables will return the same value to all objects of a class even if it is changed by another object of the same class. In the Python book that I'm reading, the author says, a data member is entered into class namespace if it's assignment takes place within the immediate scope of the class definition.  I'm using IDLE, the Python Interpreter, and below is the Python code:  class ABC:     OVRLIMIT_FEE=5  >>> a=ABC() >>> b=ABC()  >>> a.OVRLIMIT_FEE+=1 >>> a.OVRLIMIT_FEE 6 >>> b.OVRLIMIT_FEE 5   But if it enters the class namespace, should it not return same value when it is accessed with both a and b ?


Using integral test for convergence of $\sum_{n = 1}^{\infty} \frac 1 {n^3}$

How do I show that the series  $\:\large\sum_\limits{n=1}^{\infty}\large{\frac 1 {\:n^3}}\:$ is convergent using the integral test ?


I can't connect a Socket to another device - cannot evaluate StructAddrinfo.toString()

I'm trying to move a Java project I've made and tested to Android. My problem appears when I create the Socket with the Strings for the IP and port (which are not null and correspond to the IP of an open and working server). A NullPointerException appears. The code is an AsyncTask that is activated when the user presses a button. This is the doInBackground method:  @Override protected Void doInBackground(String... strings) {     client = new Client(strings[0]);     DataStorage.getInstance().setClient(client);      try {         boolean a = client.connectToServer(strings[0]); //It dies here         if (!(un).equals("")&&a) {             Toast.makeText(context,"Connected",Toast.LENGTH_SHORT).show();              Intent intent = new Intent(context, AvailableClientsActivity.class);             context.startActivity(intent);          } else {             Toast.makeText(context,"Username invalid",Toast.LENGTH_SHORT).show();         }     } catch (UnknownHostException e) {         e.printStackTrace();     } catch (IOException e) {         client.resetConnection();     }      return null; }   This is the message I get Method threw 'java.lang.NullPointerException' exception. Cannot evalueate android.system.StructAddrinfo.toString()  I've just started with Android so it might be something basic I've skipped.


Short story about a robot who wants to become a writer

I don't remember much about it, but I remember reading it about 5-8 years ago while on an Asimov kick. It may be one of his stories, but I can't remember names/places.  All I can remember is that the main character, a robot, decides that he wants to become an author and experiences opposition to his claims that a machine can be creative.  Any help?


I have followed many answers here for my case and it doesn't work.  I have some Arabic values inserted in the database. I am getting Arabic values as \u0645\u0628\u0627\u0631\u0627.  My database collation is : UTF8_general_ci Server charset: UTF-8 Unicode  Tables and columns collation are : UTF-8 Unicode   This is my connection php file :  <?php  $host=""; $user=""; $password=""; $db="";   $con= mysqli_connect($host,$user,$password,$db) or die("Unable to connect"); $sSQL= 'SET CHARACTER SET utf8';  mysqli_query($con,$sSQL);  if(mysqli_connect_error($con)) { echo "Failed to connect to database ".mysqli_connect_error(); }   $sql="select id_livestream,name_match,time_match,name_league,name_stadium,name_team1,name_team2,image_team1,image_team2,live from Livestream,staduim,League WHERE Livestream.stadium=staduim.id_stadium and Livestream.league_type=League.id_league"; $result=mysqli_query($con,$sql); if($result) {     while($row=mysqli_fetch_array($result))     {     $flag[]=$row;     }     print(json_encode($flag));     }     mysqli_close($con);    ?>   Note : Arabic values have been successfully inserted in the database but when I am retrieving the data I am getting it like \u0645\u0628\u0627\u0631\u0627


Elementary proof of the primes of the form $4n+3$

I am a highschool student going through the elementary number theory found the following please help me understanding this.     prove that there are infinitely many primes of the form $4k+3$   My book start this way :  Let $n=4k+3$ and $S=\{d\,|\,d\text{ is a divisor of $n$ of the form $4m+3$}\}$. As $n$ belongs to $S$ so $S$ is not the empty set, so there must be a least element say $p$. Then $p=\min\{d\mid d\in S\}$. Now there are two possibilities that $p$ may be prime or composite, say if $p$ is composite then $p=ab$ as $p=4m+3$ at least one of the $a,b$ must be in the same form. Say $a=4l+3$ for some $l$. Hence as $a<p$ it contradicts our assumption of minimum element. Thus $p$ is prime.    Up to this I got it but after this I am unable to grasp :    So from this we can conclude that every number in the form $4k+3$ must have at least one prime divisor of the same form. Now consider $4(n!-1)+3=4n!-1$ so from the above it should have prime divisor of the same form. But  $p$ does not divide  $4n!-1$ for any natural number  $p$ in $[2,n]$ so $p>n$. Hence there are infinitely many primes.    Please help me in the last part, I did not get why $p$ does not divide $4n!-1$ when $p$ is less than equal to $n$


i have a shuttle barebone pc (link to description: ). I would add some RAM, but i don't know if the one i want to buy is compatible (DDR3 1333 MHz 2gb 10600). Could someone help me?


What if MSE used a different rep model for privileges?

Say you're a 50k rep user on SO who, while active on MSO, only visits MSE when discussions or feature requests affect SO itself. If all you ever do is comment and vote on MSE, you can easily run yourself out of rep... thereby losing your voting voice in matters that affect your site.  How would MSE be impacted if its privileges, like those of site-specific metas, were driven by main-site participation rather than its own rep system, e.g.:   Your aggregate rep across the network Your maximum rep from any site across the network*   What would privilege distribution look like? Potential problems?  *It may be worth discussing how we could normalize for rep pool disparity between sites.


Finding the correct family of equations for the given equation

In my calculus book, (not for homework, I was just looking around), I was given the following equality and was told to find all valid functions that fit it.  Find all families of functions that satisfy the following equality: $$\bigg(\int f(t)dt\bigg)\bigg(\int {1\over f(t)}dt\bigg)=-1$$  My two failed attempts to solve this yielded $f(x)=e^x+C$ and $f(x)=e^{-x}+C$ depending on my methods.  What families of functions satisfies this relationship?


"Join this community" gives 404 when called from add comment on a site meta

Steps to reproduce:   Goto a post on a meta site you don't have account on () Click "add a comment" Click "join this community" Click "confirm and create this account" Receive 404 page not found   I have seen this on multiple site metas (Chemistry and Portuguese).


I cannot see underwater in Skyrim. Every time I go underwater everything is completly blue. I recall being able to see underwater before when I began to play the game but now I can't


What is the two-pin polarity indicator for a PCB?

I inserted a two-pin header (P1) into this circuit using EasyEDA.  Does the square outline mean that is the positive pin, or is there another meaning?


My phd advisor send me a tex version of his slides, I try to update it, but when I run it, the result is totally ruined (for example, all the graphs do not download at the right place, the slides are totally "deconstructed", the first page is totally blank, I also see that bullets are not installing correctly, I do not know where it come from). My knowledge about latex is quite narrowed.   Would you know where would it come from?   Thank you very much in advance.  Images of the result (on the left) with the original (on the right).     Edit:  It seems that the problem would come from the use of theme... When I do not use any theme, things appear better.


Find all matrices [3x3] that commute with given matrix

Find all $3\times 3$ matrices that commute with  $$A =\left( \begin{array}{cc} a_1 & 0 & 0\\ 0 & a_2 & 0\\ 0 & 0 & a_3\end{array} \right)$$  My progress:  I know that a I need to find a matrix such that $AX = XA$. However I'm getting stuck when:  $$AX =\left( \begin{array}{cc} a_1x_{11} & a_1x_{12} & a_1x_{13}\\ a_2x_{21} & a_2x_{22} & a_2x_{23}\\ a_3x_{31} & a_3x_{32} & a_2x_{33}\end{array} \right)$$  $$XA =\left( \begin{array}{cc} a_1x_{11} & a_2x_{12} & a_3x_{13}\\ a_1x_{21} & a_2x_{22} & a_3x_{23}\\ a_1x_{31} & a_2x_{32} & a_3x_{33}\end{array} \right)$$  The answer has been given as:   $$\left( \begin{array}{cc} b_1 & 0 & 0 \\ 0 & b_2 & 0 \\ 0 & 0 & b_3 \end{array} \right)$$  I don't understand how they're getting that form. Can someone please explain?


For specific functions and $a_n >0$, we can say that $\sum a_n$ converges $\iff$ $\sum f(a_n)$ converges. I want to show this specifically for the case that $f(x)=sin(x)$. This is what I have thus far (which I admit is essentially nothing). Any direction would be welcome.  Proof:  $(\rightarrow)$ $\sum a_n$ converges. We know that:  (i) the partial sums of $a_n$ are bounded.  $(\leftarrow)$ $\sum f(a_n)$ converges. We know that:  ...  This is not a duplicate of a previous question that I asked. Before, I asked for a proof of this concept (if it could be proved). This, I am asking for help with a direct application of the concept.


In five years he will come back.     After five years he will come back.      As a non-native speaker, these two sentences are grammatically right for me.  But semantically speaking, I think there is a slight difference. Could anyone explain the difference to me?


How can I remove system apps on my amazon fire 7 9th gen tablet using adb commands?

I'm tired of bloatware on my amazon fire 7 tablet (9th gen)


problem in installing : unmet dependencies

When I try to install any application or update, it shows unmet dependencies- Try apt-get -f install.  How to solve this ?


I'm trying to set up individual system sounds for ubuntu 15.04. I've read some instructions but they're a bit pithy for me.  Is there an app to add?


Minecraft Sign Command give tool help [1.8]

I'm trying to make a command that summons a sign that you can buy a certain item from, however I keep on getting a error with inserting the lore and the custom name, the command that I have used is,  /give @p sign 1 0 {BlockEntityTag:{Text1:"[{\"clickEvent\":{\"action\":\"run_command\",\"value\":\"/tellraw @p[score_Grains=0] {\\\"text\\\":\\\"You do not have enough Grains to buy that\\\",\\\"color\\\":\\\"dark_red\\\"}\"},\"text\":\"[Buy]\",\"bold\":\"true\"}]",Text2:"[{\"clickEvent\":{\"action\":\"run_command\",\"value\":\"/tellraw @p[score_Grains_min=1] {\\\"text\\\\\\\":\\\"You just bought 1 Test for $1\\\",\\\"color\\\":\\\"dark_green\\\"}\"},\"text\":\"Test\",\"underlined\":\"true\"}]",Text3:"[{\"clickEvent\":{\"action\":\"run_command\",\"value\":\"/give @p[score_Grains_min=1] minecraft:paper 1 0 {display:{Name:"Test",Lore:["Test"]},ench:[{id:0,lvl:10}]}\"},\"text\":\"$1\",\"color\":\"green\"}]",Text4:"[{\"clickEvent\":{\"action\":\"run_command\",\"value\":\"/scoreboard players remove @p[score_Grains_min=1] Grains 1\"},\"text\":\"1\"}]"},display:{Name:"Buy Test"}}   However, there is a error message which is,   [13:21:48] Data tag parsing failed: Unexpected token 'T' at: Test",Lore:["Test"]},ench:[{id:0,lvl:10}]}\"},\"text\":\"$1\",\"color\":\"green\"}]",Text4:"[{\"clickEvent\":{\"action\":\"run_command\",\"value\":\"/scoreboard players remove @p[score_Grains_min=1] Grains 1\"},\"text\":\"1\"}]"   What is wrong? And how do I fix this?


Compare element between two similar array

Suppose such a minimal task to select elements in B but not in A  file_list1=(a.sh b.sh c.sh) file_list2=(b.sh c.sh d.sh)  for i in files_list1; do     for k in files_list2; do         if [[ $k in $(echo $i) ]]; then         echo          else         echo $k         fi     done done   it report errors:  $ bash compare.sh  compare.sh: line 5: conditional binary operator expected compare.sh: line 5: syntax error near `in' compare.sh: line 5: `        if [[ $k in $(echo $i) ]]; then'   if not apply in, how could get the code working?


how to select a proper aperture for 50mm portrait lens?

I am using 50 mm 1.8 potrait lens with my canon 600D. But when i take a portrait with f1.8 on Av mode using autofocus, only subjects eyes are sharp and rest of the other face is slightly blurry. How to overcome this?


Can I dynamically create a list of variable type?

I have 4 public classes, with a bunch of properties each: MoveUpdateEntry, FullServiceEntry, SeamlessAcceptanceEntry, and UndocumentedEntry. I have a dictionary containing excerpts of a given filename, along with a correlation in place to determine the string equivalent of the class's name I need to instantiate: private static Dictionary<string, string> dEntryCorr = new Dictionary<string, string>() {     {"MU_MU", "MoveUpdateEntry" },     {"FS_BQ", "FullServiceEntry" },     {"FS_BF", "FullServiceEntry" },     {"SE_NS", "SeamlessAcceptanceEntry" },     {"SE_U_", "UndocumentedEntry" } };  , but simply trying to run the following gives me an error: string fileToProcess = "MU_MU.json"; Type entryType = Type.GetType( dEntryCorr[ fileToProcess.Substring(0,5) ], true );  System.TypeLoadException: 'Could not load type 'MoveUpdateEntry' from assembly 'DataLoaderJSON, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'.' My end goal here is to be able to dynamically pick a type to make a List<> of, based on the filename. (e.g. MU_MU.json will create List<MoveUpdateEntry>, FS_BQ.json creates List<FullServiceEntry>, etc.) Is this possible in C#? TLDR: I want to create a List<> with a class type that is determined by a string. This is a matter of abstraction.


In Views admin, is there a section to insert CSS to style the view? i.e. how to style view without editing theme code or other drupal PHP?

In the Views admin (i.e. admin/structure/views ), is there a section in the settings to insert CSS to style the view? i.e. how do I style a view without editing theme code or other drupal PHP?   I am able to find out which class identifiers that I need to style - see question/answer at:   But I don't know where to put the CSS code to actually style the view.  I assume that it is possible to style a view within the drupal views admin pages, without having to resort to editing/creating themes, PHP and HTML code via FTP (?). Obviously one can do those things too but I'd rather try to find a (non-theme specific) solution within the views admin first.


How to get a bunch of letters/envelopes (PDF) from a list of clients (CSV)?

Say I have a letter like this:  \documentclass{letter} \usepackage{hyperref} \signature{Joe Bloggs} \address{21 Bridge Street \\ Smallville \\ Dunwich DU3 4WE} \begin{document}  \begin{letter}{Director \\ Doe \& Co \\ 35 Anthony Road \\ Newport \\ Ipswich IP3 5RT} \opening{Dear Sir or Madam:}  I am writing to you on behalf of the Wikipedia project (http://www.wikipedia.org/), an endeavour to build a fully-fledged multilingual encyclopaedia in an entirely open manner, to ask for permission to use your copyrighted material.  % The \ldots command produces dots in a way that will not upset % the typesetting of the document. \ldots   That said, allow me to reiterate that your material will be used to the noble end of providing a free collection of knowledge for everyone; naturally enough, only if you agree. If that is the case, could you kindly fill in the attached form and post it back to me? We shall greatly appreciate it.  Thank you for your time and consideration.  I look forward to your reply.  \closing{Yours Faithfully,}  \ps  P.S. You can find the full text of GFDL license at \url{http://www.gnu.org/copyleft/fdl.html}.  \encl{Copyright permission form}  \end{letter} \end{document}   And say I have a list of clients like this:    How can I run a loop through my list of clients to produce letters and envelopes for each one so that each is addressed correctly?


How do you prove Cov $\left( \bar{X} , X_i - \bar{X} \right) = 0$?

How do you prove Cov $\left( \bar{X} , X_i - \bar{X} \right) = 0$ given $ X_1 ,..., X_i$ are i.i.d. each with variance $\sigma^2$ and $\bar{X}$ is the sample mean?? In other words, how do you show that the sample mean and the differences of the observations from that mean are not linearly correlated???  Am I on the write track?  I've written  $Var \left( \bar{X} + \left( X_i - \bar{X} \right) \right) = Var  X_i =  Var \bar{X} + Var \left( X_i - \bar{X} \right) + Cov \left( \bar{X} , X_i - \bar{X} \right)$ .   I know  $Var  X_i = \sigma^2 , Var \bar{X}= \frac{\sigma^2}{n}$, so all I need left to find the covariance is $Var \left( X_i - \bar{X} \right)$.   I don't know if this is right, but I wrote  $Var \left( X_i - \bar{X} \right) = E\left( \left( \left( X_i - \bar{X} \right) - \mu_{ X_i - \bar{X}} \right)^2 \right)=E \left( \left( X_i - \bar{X} \right)^2 \right)=s^2$, but I don't know if that's right or helpful at all.   Am I on the right track??


App crash when editing comment or uploading image

I've got a , the latest version of the Stack Exchange app, and here is the repro video:         Original Link to video gif:   Also, when I tried to upload this GIF file to this question, again using my phone, choosing the GIF file from the device also crashes the app, hence the Imgur link.  I've edited comments on my phone before, so I know it works/worked. All of a sudden the app is crashing.


How to install netbeans v8.1 in Ubuntu 14.04?

Nobody seems to talk about version 8.1, can anyone please guide me through?


Regex validation for North American phone numbers

I am having trouble finding a pattern that would detect the following   909-999-9999   909 999 9999  (909) 999-9999  (909) 999 9999  999 999 9999   9999999999  \A[(]?[0-9]{3}[)]?[ ,-][0-9]{3}[ ,-][0-9]{3}\z   I tried it but it doesn't work for all the instances . I was thinking I can divide the problem by putting each character into an array and then checking it. but then the code would be too long.


Posterior derivation with prior as Normal-Gamma distribution

I am studying Gary Koop's Bayesian Econometrics , it is bit confusing in the beginning. I will reproduce some results from the textbook here in order to smoothly move to my question.   For a simple linear regression model with normal distribution assumption for the error term, its likelihood can be rearranged into $$p(y|\beta, h)=\frac{1}{(2\pi)^{N/2}}\bigg\{h^{\frac{1}{2}}\mathrm{exp}\bigg[-\frac{h}{2}(\beta-\hat{\beta})^2\sum_{i=1}^Nx_i^2\bigg]\bigg\}\bigg\{h^{\frac{\nu}{2}}\mathrm{exp}\bigg[-\frac{h\nu}{2s^{-2}}\bigg]\bigg\}$$ the first curly brace on the right hand side resembles Normal distribution, the second curly brace resembels Gamma distribution, where $h=\frac{1}{\sigma^2}$, $\nu$ the degree of freedom, $s^2=\frac{\sum (y_i-\hat{\beta x_i})^2}{\nu}$, $N$ the sample size.   Then we have a natural conjugate prior, with a Normal-Gamma density $$\beta,h \sim NG(\underline{\beta},\underline{V},\underline{s}^{-2},\underline{\nu})$$, underline indicates the prior parameters. $\underline{V}$ is the variance of $\beta|h$.  After this, the author provide the posterior directly $$\beta,h|y \sim NG(\bar{\beta},\bar{V},\bar{s}^{-2},\bar{\nu})$$ where  $$\bar{V}=\frac{1}{\underline{V}^{-1}+\sum x_i^2}$$ $$\bar{\beta}=\bar{V}(\underline{V}^{-1}\underline{\beta}+\hat{\beta}\sum x_i^2)$$ $$\bar{\nu}=\underline{\nu}+N$$ and $\hat{\beta}$ is the OLS estimate.   I have no idea how author get these results, I checked the reference he mentioned, but I still could not figure out the deriviation. Would anyone show me how do get posterior as author did under these model settings? Thank you!!


In TF2, I have heard of a term known as "Gib" What exactly does this term mean? There is even a strange part called: "gib kills" What does that mean? Low health kill? Adrenaline kill?   Could I please have some clarification on what both terms mean? Both the term "gib" itself and "gib kills".


If a multivariable continuous real function has $\lim_{\Vert x\Vert\to\infty} f(x) = L$, it is then uniformly continuous?

An exercise sheet of my Multivariable Calculus subject asks you to prove that a continuous function $f:\mathbb{R}^n\longrightarrow\mathbb{R}$ is uniformly continuous if $\lim_{\Vert x\Vert\to\infty} f(x) = L$. I think I have nevertheless found a counterexample: taking $n=1$, the function $f(x)=\sin(1/x)$ for $x\neq 0$, $f(0)=0$ has limit 0 as x approaches both negative and positive infinity, but it is not uniformly continuous. Is my reasoning correct? Otherwise, can you give me some hints on how to deal with this proof? Thanks in advance.


Assume f is a bounded continuous function on $\mathbf{R}$ and $X$ is a random variable with distribution $F$.  Assume for all $x \in \mathbf{R}$ that  $$ f(x) = \int_\mathbf{R}f(x+y)F(dy) $$  Please help conclude that $f(x+s) = f(x)$ where $s$ is any value in the support of $F$.  The hints that I have come across are to use Martingale theory and consider $\{ X_n\}$ to be i.i.d. with distribution $F$ and make a martingale with some function of $S_n = \sum_{j=1}^nX_j$.    Thanks!


I want my table to look like the one below:   But this is what is turning out:   Here’s an MWE:  \documentclass{article}  \usepackage{multirow}  \begin{document}  \begin{tabular}{|c|c|c|} \cline{1-3} \multicolumn{1}{c}{} & \multicolumn{2}{c}{Treatment Received}\\ \cline{2-3} & All Respondents & Prejudiced Respondents\\ \hline Culturally Foreign &    25.6 & 44.4\\  Culturally Familiar & 20.0 & 19.0\\ Difference & 5.6 & 25.4*\\ (95\% Confidence Interval) & (-1.1 to 12.4) & (6.6 to 44.1)\\ p-value & 0.101  & 0.009\\ \hline \end{tabular}  \end{document}


How do I calculate weapon damage as I level up?

I updated my weapons' damage rolls with the help of a friend when I reached level 13, but now I'm level 16, and I don't know how to do it myself.  My weapons are a huge size Chakram (ranged), a Web Knife (melee) and a Whip Dagger (ranged(with the Web Knife attached.)) At level 13 they were:   2d6+14 for my Chakram. 1d6+6 for the Web Knife. 1d8+6 for the Whip Dagger.   My current attack bonuses are +19/+14/+9 for melee and +18/+13/+8 for ranged. My Strength is 24. I have the Brutal Throw and Boomerang Throw feats.


Why do we say "try and" [verb] instead of "try to" [verb]? (E.g., "Try and call me tomorrow.")

In written and standard semi-formal (and above) spoken English, one would use "try to":  Try to be a better person. Try to get the fishhook out of my thumb, please. Try to find a pharmacy when you need one.  But in spoken English, we (Americans, at least) usually substitute "try and" for all those cases. "Try to" makes sense because the "to" begins the construction of an infinitive: "try to be", "try to do", "try to act" and so on. "Try and" on the other hand doesn't seem to make any sense. I'm curious how the "try and" crept in, and when. It's really tough to Google small words like these, so I'm not finding anything on the Web. Is it a contraction of something like "Try hard, and ..."? Note: I've seen  and it is somewhat related but doesn't tell me what I want to know. Edit Observe how, even on this site,  construction. Turning it on its head Note that you can't make a negative construction with "try and":  It's raining. Try not to get wet. It's raining. Try not and get wet. [?]  Even adding do doesn't help. The following means something different from "try not to get wet."  It's raining. Don't try and get wet.  Even use of to instead of and there means something else:  It's raining. Don't try to get wet.  "Try not to get wet" means try to stay dry. "Don't try to get wet" means avoid actively seeking out a soaking, and implies that a soaking might in fact be what you are looking for. MORE I just happened to notice a video from an editor for Merriam-Webster on this very topic, so I include the link here: .


I just , and rejected it for "no improvement whatsoever."  When I hit the "reject" button, I noticed that the text box for entering a custom reject reason is wider than the whole reject box:    This was seen today in Chrome 40.0.2214.93 (and thank you for making me check the version, I'm currently updating my browser)  I believe this is a .


There is a bug in beamer which is quite annoying, and I don't know how to solve it properly. In my theme, the title of a frame is always in white:    However, if the example block is empty, or if it contains only a list, the frame title is black, which makes it hard to read:    Do you know why, and how to solve this problem? I tried to add at the beginning a tilde,but it adds an empty line that I don't like...  Thank you.  MWE  \documentclass[]{beamer} \usepackage[T1]{fontenc} \usepackage[utf8]{inputenc} \usepackage[francais]{babel}      \usetheme{Warsaw}  \begin{document} \begin{frame}{My great title}   \begin{exampleblock}{Exemple}     \begin{itemize}     \item a     \item b     \end{itemize}   \end{exampleblock} \end{frame} \end{document}


Any help is greatly appreciated!     Outline: Hermione has been thinking about the imminent return of the Dark Lord, so she has been busy packing her bag with all the items required for her survival. Because she has so many different items, it is impossible to list them all here; however she knows that she can formulate the problem even without knowing those (trivial) details. She has $N$ items indexed from $1$ to $N$; each item $x_i$ is associated with a value $c_i$, weight $w_i$ and volume $v_i$. She cannot carry more than $W$ in weight, and the bag can only hold up to $V$ in volume. Items must either be in the backpack or not; i.e. we cannot put half a book in the bag! She needs to maximize the value of the items that she is carrying, because she knows she will not be able to replenish these for a very long time.   How would I formulate this problem using summation notation?


How to standardize data for hierarchical clustering?

When running hierarchical clustering analysis of a matrix of individuals x samples (e.g., employee performances across different days), there are several possibilities for normalization. If one is clustering the columns (to see whether on certain days individuals perform similarly), one could   z-score normalize across the rows to make each individual employees mean and standard deviation comparable across days, or z-score normalize across the columns to make all employees comparable within a day, or  not normalize at all and cluster the raw values   Could someone explain the relative advantages/disadvantages of each approach here? To clarify, I am using correlation distance.  Methods 1 or 2 in practice give different results but it's not clear that for the task of seeing if days cluster together, whether #1 or #2 are more appropriate if one chooses to normalize.


What is the maximum value of $n$ if $n + 5$ divides $n^5 + 5$, $n$ being a natural number? I tried to solve by binomial theorem but it failed.


Word for someone that always has to be right

Is there a word for someone that always has to be right? The person gets angry if they are not.


Audio from VLC will get quiet when focusing other applications

OS: Windows 8.1  I'm noticing that when playing something from VLC (though it happens when playing audio from Chrome) that my sound will pseudo-randomly become quiet.   Chiefly it happens on the 'new tab' screen of google chrome, as well as google searches through windows chrome. It will occasionally happen when I open other applications - though I've not yet found any rhyme or reason to it.  Device is the built-in realtek device through my headphone jack, driver is most current according to their website.   Not really sure how to diagnose or fix this. Help appreciated.  EDIT: Logging in as a different user fixes the issue. Disabling all extra chrome extensions does not. Still looking for a solution for my regular user account.  Related:   List of things causing the issue:   Chrome Launching a windows 7 virtualbox VM (not VBox manager though) Mumble Will update with more as found NOT Foobar2000 (I had suspected the issue may be coming from applications that play sound?) Installed Skype to test, during the initial 'setup' of my account (for sound/mic/video) my audio was hushed, despite that I have the 'communications activity' set to 'do nothing'.


Books with mages exploding on death normally - but not when other mages siphoned their magic through their blood in their last moments

I remember reading a series of three books that started in some sort of slum with the female protagonist. At a certain point every kid, no matter the status, is tested for their ability to use magic. This is because magic can be extremely problematic when left alone. Mages normally explode quite violently when they die and their remaining magical energy gets out of control. Therefore everyone with an aptitude for magic gets recruited and trained in a special school to learn how to use magic.  The school also has a room where mages are supposed to die without hurting anyone. But strangely for most people, there is also some sort of old graveyard and nobody understands why - after all there is no body to bury if a mage dies.   The protagonist learns a lot of simple magic - little shields to be safe from physical attacks and methods to raise the core temperature when it's cold outside. Raising the core temperature was mentioned as something students starting in winter would learn really fast - they were only allowed certain clothes in the school.   The problem comes later in the books. The reader learns that there are other kinds of mages who were banned a long time ago and lived in the desert. They still knew how to raise their magical energy, which normal mages of the current time forgot. By cutting someone and touching their blood a mage could siphon their energy and increase their own pool of energy. The normal process was that there was one master and one student. The master taught the student and in turn got to take their magical energy. This also allowed to take all of the energy of a mage in their last moments, which means there was no energy to go wild after death and therefore no explosion.   By constantly increasing their magical energy their spells were extremely powerful. Once these people learned that others forgot about extracting magical energy from others they decided to start a war. They could easily kill most of the normal mages. Those were extremely weak compared with the bad guys and didn't expect such power.   Luckily the protagonist and one of her teachers(?) were different. He knew about this kind of magic and taught her about it. So they started fighting back and I think in the end they were able to defend themselves against the invaders by showing them, that the old knowledge was not lost and killing a handful of the enemies. Their numbers were really low and explosions from mage deaths were extremely devastating after all.   The magic system was really fascinating and I would love to read them again, but I only borrowed them from a friend around 2010 or so. I've read the books in German and each one had the female protagonists name in the title.   Can you help me remember what the name of the series was


In Objective-C, id<protocol> or NSObject<protocol> are frequently used for delegate declaration.  What are the main differences between id and NSObject? When do you want to use one versus the other?


How to guarantee existence of a finite field

Existence of a finite field:  Solution:  I can understand that if I  have a finite field $F$ of characteristic $p$ where $p$ is prime then I can consider $\mathbb Z_p$ as its prime field and hence $F$ will have $p^n$ elements  But how to find such a field $F$ ?


How to take a screenshot with an Android device?

Is there a way to take a screenshot of an Android device and save it as an image file?


I was wondering what the best way to go about updating a semi old version of R to the latest version, which I believe is 3.2.2-1. I havent needed it for a while but now will need it more with a few features that are only on the latest version.


Changing itemsep without using enumitem package

I know that you can change the itemsep of an itemize environment by loading the enumitem package. To the extend of my knowledge, this method has the disadvantage that every time I use an itemize/enumerate environment to manually adjust itemsep.  Thus, I want to ask if there is a method (preferably) or a package in which I can set itemsep=0.2cm (or its corresponding value in pt) globally (i.e. for my entire document).  Thanks in advance!  PS: A workaround is to record a macro with my settings (itemsep, label, etc..). However, I don't think that is a proper way to handle such thing


how do I bypass frp without sim card on boost mobile zte prestige?

I need to bypass or find a way to make a zte prestige w/o sim card boost (mobile) into a wifi phone or a phone that can at the very least connect to wifi for internet. it will connect to wifi but it wont open anything so there's no way to get internet or get to a browser because of FRP Google Lock. Anyone know how I can use the internet at the very least and/or bypass the google frp or get internet browsing capabilities? Thank you, appreciate any help.


Append huge files to each other without copying them

There are 5 huge files ( file1, file2, .. file5) about 10G each and extremely low free space left on the disk and I need to concatenate all this files into one. There is no need to keep original files, only the final one.  Usual concatenation is going with cat in sequence for files file2 .. file5:   cat file2 >> file1 ; rm file2   Unfortunately this way requires a at least 10G free space I don't have. Is there a way to concatenate files without actual copying it but tell filesystem somehow that file1 doesn't end at original file1 end and continues at file2 start?  ps. filesystem is ext4 if that matters.


If $R$ is commutative, the left $R-$module can be given the structure of right $R-$module.

The definition of the module is given in Hungerford's Algebra by:    And I can not understand the following paragraph, could anyone explain this for me please especially why commutativity is needed for (iii)? Thanks!!


I have created a folder in my file system called "opt". It contains two other folders. How do I delete it with signing in as a root user? Thanks


When I am trying sudo add-apt-repository --yes ppa:persepolis/ppa its showing  Hit:1 http://ppa.launchpad.net/persepolis/ppa/ubuntu bionic InRelease           Get:2 http://security.ubuntu.com/ubuntu bionic-security InRelease [83.2 kB]     Hit:3 http://in.archive.ubuntu.com/ubuntu bionic InRelease                      Get:4 http://in.archive.ubuntu.com/ubuntu bionic-updates InRelease [88.7 kB]    Ign:5 http://ppa.launchpad.net/ubuntu-wine/ppa/ubuntu bionic InRelease          Err:6 http://ppa.launchpad.net/ubuntu-wine/ppa/ubuntu bionic Release              404  Not Found [IP: 91.189.95.83 80] Hit:7 http://in.archive.ubuntu.com/ubuntu bionic-backports InRelease Reading package lists... Done E: The repository 'http://ppa.launchpad.net/ubuntu-wine/ppa/ubuntu bionic Release' does not have a Release file. N: *****Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.***** .   please Solve this!!


How to turn packages with an install.sh into a .deb file?

I'm trying to install the arduino ide from a tar archive it happens to have an install.sh. I don't want to install by running it straight up because it won't show up on apt or synaptic. (The package isn't available on a PPA) Is there a way I could turn it into a .deb package? I know checkinstall is used for things with a make but here that isn't the case. I was wondering if this is possible.


How to deal with slow peer reviewing process

I submitted a short (10 page long) manuscript to a math journal. It has been 9 months. Almost 4 months ago I emailed them to see what's going on. Their response was: "Your paper has been sent out to review but we haven't heard back".  What are the options at this point? The journal is one of the best in the field but at the same time I'm concerned thaat I might wait a long time just to receive a rejection letter.


408 error in browser using Google or openid on some networks in Ubuntu

I have searched here and the web and many other people have similar issues going back a few years ( for example), but no one seems to have fixed it.  I get the same results in Chrome, Firefox and Epiphany browsers. Have done complete removal's and re-installs of them all and Ubuntu.  I originally had this problem in Mint, but re-installed Ubuntu, same problem  I have this problem on 3 Ubuntu machines, 2 on 13.10 (fresh installs, not upgrades) and one on 11.10, the 11.10 dualboots windows 7 and that is what I am using now.  Only in windows can I log on to any Openid site, and only on windows can I use all Google services with out problems.  Dropbox client in Ubuntu can not connect, windows can.    So Openid and Google search results time out, in firefox I get the 408 error, in chrome the oops message.  But I can log into Gmail without problems in both browsers.  With all of them the problem started with a change of service from my ISP (worldnet.co.nz when I moved from adsl to fiber optic or UFB).  Speed tests using speedtest.net produce similar download speed, but the Ubuntu machines are unable to do the upload tests, it just sits on 0.00 for as long as I can wait.  One of the machines is a laptop and it works fine when I take it else where and use other networks.  So this would appear to be a network issue, but after 2 weeks my ISP can find nothing wrong, and have completely removed any firewall protection from my connection.  My main desktop is in the DMZ zone for my router, I have a static IP address, and no fire wall running on it at present.  Windows 7 works correctly which suggests my ISP is correct when they say it's not a problem at their end. My router does not support IPv6 and I have disabled IPv6 in one of the machines, no change.  Ubuntu updates work fine, I have no problems with apt-get.  I can browse all generic web sites like www.nzherald.co.nz or askubuntu, but I can't log into some sites.  I have tried changing dns servers, no difference, and nslookup and dig return the expected results always.  traceroute works fine.   Can any one help here?    I have installed dnsmasq. unistalled it, tried static ip, dhcp (my router is assigned static ip by my isp which changed with the new fiber connection).  Tried Google dns, my isp dns manually added, auto assigned dns.  ifconfig reports a virbr0 interface on 192.168.122.1, the rest of the machines on my router are on 192.168.0.* and I do not know where this virbr0 comes from.  Gnome boxes maybe?  All machines on the router can see each-other in files folders.  So to recap, a fresh wipe all data re-install does not fix it, booting of the Ubuntu 13.10 live usb shows the same problems.  Windows has no problems.  Please help me, as bizarrely this seems to be a problem with Ubuntu only.  Thanks,


can't change file permissions of key file

I have a .pem file. The normal chmod [4/6]00 [key_name_here].pem command doesn't work. The permissions are stubbornly stuck at 444 or 644.


The images on the stack snippets blog post are broken

On , none of the images show up for me. Several others .  I can still click the broken image links and they open on imgur normally.  The images in  I've checked seem to work fine. This includes  which are broken according to .


How and from where does a mathematician learn physics from a mathematical stand point? I am reading the book by Spivak . The first couple of pages of Lecture 1 of the book summarizes what I intend by physics from a mathematical stand point. I wanted to find out what are the other good sources for other branches of physics.


Is there any way to override the standard css provided by salesforce in LWC?  I tried the way we did for aura components but it doesnot seem to affect the structure in any way.  Do we have different method of doing so?


What would happen to a star if a Dyson sphere lined with mirrors reflected a significant portion of the stars light back to the star

I have looked for similar questions here on stack exchange. The closest example to this that I found is . That question assumed less than perfect absorption of material lining the inside of the sphere, and the effect of thermally re-radiating it inside the sphere.  A lot of the answers focused on that much of the thermal radiation would not be reflected back to the star, and is likely to be reabsorbed by the sphere at another location. On the other hand, this question asks what would happen if the Dyson sphere, using mirrors, deliberately refocus a significant portion of the rays directly back at the star.


One Object Looks Like Material / Texture is Noisy

I have rendered a 2 min animation that I'm pretty happy with (my first go with Blender) using models I created. The render was great, noticed a few mistakes so I was going to do some more editing.   I now notice one of the objects has become very noisy, screenshot below. I can't get the texture back. Everything looks fine within Material & Texture in the Properties section of the object. I've even tried to relink the material and UV maps from the object beside it in the screenshot as they are essentially the same object.   Have I just accidentally added noise to the object somehow? To new to Blender to figure it out.  Thanks in advance.