Using GDAL Virtual I/O (/vsicurl) when Adding a Geoserver Store

I was under the impression that configuring Geoserver with the GDAL plugin would allow me to utilize GDAL's virtual I/O prefix for accessing data stores in a zip file, s3, etc. using /vsicurl/ or /vsis3/.  Having gone through the installation of GDAL and geoserver, I am able to use gdalinfo with the vsi prefix to successfully retrieve information about a file hosted in cloud, but when attempting to do this by adding a data store, I'm pretty sure Geoserver thinks this is just a file.  Any tips?


Intersection between line and circle doesn't go all the way

I'm trying to get the intersection point between a line and a circle but then when I draw from that point to another it does not start just at the intersection. Here is my code:    \documentclass[margin=1mm]{standalone}  \usepackage{tikz} \usetikzlibrary{intersections}  \begin{document}     \begin{tikzpicture}         \draw [name path = circle]         (0,0) circle (1);          \path [name path = en1] (-3,.4)--(3,.4);         \path [name path = en2] (-3,-.4)--(3,-.4);          \draw [name intersections={of=en1 and circle}]         (intersection-1) node (ne) {}         (intersection-2) node (no) {};          \draw [name intersections={of=en2 and circle}]         (intersection-1) node (so) {}         (intersection-2) node (se) {};          \draw         (0,0) -- (ne);     \end{tikzpicture} \end{document}   And my result:


I wanted to put a link to one of the comments on  into chat. But it seems that isn't supported, for some reason. Normally you can just click the "x hours ago" link on a comment, and that takes you straight to it and lets you link to it. But on the election page there's no link, just straight text.  I'm guessing this is intentional, because it would be a really weird bug, but I'm wondering 1) why this is the case and 2) if there isn't a really compelling reason, can we change it? I'd like to be able to discuss nominations with people and point out specific comments, just like I would with any other post.


Finding differences between shapefiles using ArcGIS for Desktop?

Every month I have to QA/QC some streets data for an entire county (over 47,000 records). The first step is to compare the two files. Currently, I'm using a tool that was created in house via VBA approx 5 years ago. It works compares the two files and reports back the differences based on a few factors (added records, deleted records, address changes, city changes, segment length/vertices changes). I then export these to individual shapefiles. Additionally, the tool works in ArcGIS 9.3 but will no longer work in ArcGIS 10.1  The tool works great, but it takes approximately an hour to complete.  I've started to work on hopefully improving this tool to speed up the performance. I've looked into a variety of methods including the Compare Feature Tool and Select by Location.   Both of these tools work significantly faster, however, they don't seem to capture everything that I need. The big issue I have with the Compare Feature Tool is that I cannot choose which field to compare on. It defaults to ObjectID when I need to compare by Segment_ID. There isn't an option to select that.   Does anybody have a good solution or ideas on how to achieve a full compare like I've described?    For some reason, ArcGIS isn't recognizing the join that I'm attempting per RyanDalton's answer.   But  Taking the advice of a join I have figured out how to find the added records and deleted records differences in the two files by:   Joining the Previous Month shapefile to the Current Month shapefile via the Segment_ID field Performing a definition query where Segment_ID IS NULL Exporting that to a new shapefile (Added Features)   I then reverse the joins and find the Deleted Features  Still working on a way to find the other differences listed and then string them all together in a model.    I can find all records that have changed by performing a select by location records from one of the datasets that are identical to the other dataset. I then switch the selection and it gives me all the records that are not identical.  I'll put it all in a model and hopefully it works just as well.


iOS App Store: Can't scroll to see more results

When searching with a keyword in the App Store app on my iPhone, I unable to scroll to see more results. What could be causing the issue? I am running iOS 12.


Best way to compare 2 XML documents in Java

I'm trying to write an automated test of an application that basically translates a custom message format into an XML message and sends it out the other end.  I've got a good set of input/output message pairs so all I need to do is send the input messages in and listen for the XML message to come out the other end.  When it comes time to compare the actual output to the expected output I'm running into some problems.  My first thought was just to do string comparisons on the expected and actual messages.  This doens't work very well because the example data we have isn't always formatted consistently and there are often times different aliases used for the XML namespace (and sometimes namespaces aren't used at all.)  I know I can parse both strings and then walk through each element and compare them myself and this wouldn't be too difficult to do, but I get the feeling there's a better way or a library I could leverage.   So, boiled down, the question is:  Given two Java Strings which both contain valid XML how would you go about determining if they are semantically equivalent?  Bonus points if you have a way to determine what the differences are.


What are the eigenvalues of matrix that have all elements equal 1?

As in subject: given a matrix $A$ of size $n$ with all elements equal exactly 1.   What are the eigenvalues of that matrix ?


Why does the command chmod 6754 correspond to the file permissions rwsr-sr-?  I understand that Read = 4, Write = 2, and Execute = 1, but what value does the s (setuid) permission or the dashes have?


Looking for a template which reference paper has a title

I guess this question has been asked several times but still I did not find a solution :(  I used the template for physical review A, \bibliographystyle{spphys}, which the reference paper only has author name, journal title, volume, page e.g.     XXX, Phys. Rev. Lett. XX, XX (XXXX)   I need a template that could display the title of the quoted paper.  e.g.     XXX, title, Phys. Rev. Lett. XX, XX (XXXX)   Where can I find such a template? and/or bst file?


What is gained by giving categories an identity arrow?

We give groups their axioms of closure, associativity, inverse, and identity, so we can "do algebra" or equivalently, study symmetries in a very general sense. What new can we do by adding the requirement that a category contain arrows from an object to itself? Surely this removes some level of generality, which I think the idea of creating categories was seeking after?   I know there are many examples of categories, and that this is used to show the importance of them. But I'm sure there's a reason we use categories in each case, and that there must be at least a vague thread that goes through all of them. I'm not so interested in specific applications, if possible but if so that's fine.   QUESTION: by giving category objects unique identity arrows what useful (but AS GENERAL AS POSSIBLE) property is gained? Since I'm not familiar with this part of math I'd appreciate something that's intuive and in layman's terms. :) Thanks.


I have an application that needs to manage a priority queue of some items, where the priorities themselves can actually be fractional quantities (like 2.4 or 0.3). Smaller is better, as with usual integer priorities. The following one-liner generates a DoubleStream with DEFAULT_CAPACITY - many doubles pseudo-uniformly distributed between 0 and SCALE:  DoubleStream priorities = IntStream.range(0, DEFAULT_CAPACITY).map(_ -> r.nextDouble() * SCALE);   My question is: how can I avoid the unnamed parameter _ in the lambda that is given as an argument to map? Unfortunately, Random::nextDouble() is not static, so a method reference is not possible.   This question generalizes, of course: lacking a static method and given a known number of iterations, how can we avoid an unnecessary unnamed lambda parameter? Effectively, the generation of an intermediate Stream (the result of calling IntStream::range()), should really not be necessary.  // Edit: After looking at my IDE a bit closer, I am noting that the syntax above is actually NOT compilable since Java 9! The compiler says: As of Java 9, '_' is a keyword, and may not be used as an identifier. So this question is even more important to me now :)


Can not install Ubuntu 16.04 or 16.10 on Asus GL 552vx

I have Asus GL552VX with Corei7 6700hq, 16Gb RAM and 128 Gb SSD.  I tried with both Ubuntu 16.10 and 16.04.  I create bootable USB with Rufus.  And the installation stop at the loading screen forever.... ( so sad )  Does anyone know what is the issue?  And which version of ubuntu can be installed on my machine ?  Thank


It is very well known that the higher the viscosity the higher the resistance offered.  But why do we slip more on oil as compared with water even if oil has higher viscosity than water?


If $A/I \cong A/J$ as rings and $I\subseteq J,$ then $I=J.$

Let $A$ be a commutative Noetherian ring and let $I$ and $J$ be ideals of $A.$  Suppose that $I\subseteq J$ and that $A/I \cong A/J$ as rings.  I want to prove that $I=J.$    Observations so far:  1) If we drop the hypothesis $I\subseteq J,$ then the result is false:  $$\mathbb{Q}[X,Y]/(X)\cong \mathbb{Q}[X,Y]/(Y) \text{ but } (X)\neq (Y).$$  2) If $A/I\cong A/J$ as $A$-modules, then $I=J$:  $$I=\mathrm{Ann}_A(A/I)=\mathrm{Ann}_A(A/J)=J.$$  I'm now a bit stuck as to how to proceed. Any hints would be most helpful!  Many thanks :)


Is it possible that the speed of light has changed since the beginning of the universe?

Asking purely out of curiosity:  Is there any research or publication in Modern Physics that considers the possibility that the speed of light has changed since the Big Bang, and not remained constant (as what we know it today)?  By changed, I mean either gradually or abruptly, though I guess that the former makes more sense.  Now, I am guessing that the answer to this question might be more of "a matter of terminology".  For example:  We can say that the speed of light hasn't changed in the perspective of everyone who is within the given space, but since this space by itself has expanded, anyone theoretically "outside it" will "see" that light is in fact covering a larger distance per time unit (larger than what it used to when the given space was smaller)... Or we can say that it has slowed significantly, while the universe itself hasn't expanded at all.  On the other hand, I might be speaking nonsense here, so I'd be happy if one of you out there (or here) could enlighten me on this...


Show that $E(X)=\sum_{n\in\mathbb{N}}P(X\ge n)$

Let $X$ be a discrete random variable over $\mathbb{N}$, $E$ its expected value.  I want to show that $\displaystyle E(X)=\sum_{n\in\mathbb{N}}P(X\ge n)$  I thought of an "Euler sum" approach :  $\displaystyle E(X)=\sum_{n\in\mathbb{N}}nP(X=n)=P(1)+2P(2)+3P(3)+\cdots=\\ [P(1)+P(2)+P(3)+\cdots]+[P(2)+2P(3)+\cdots]+\dots=[P(1)+P(2)+P(3)+\cdots]\\ +[P(2)+P(3)+\cdots]+[P(3)+\cdots]+\cdots=\sum_{n\in\mathbb{N}}P(X\ge n)$  but that approach seems "too easy" and not rigorous enough to me (I do know that changing the order of the terms in the expected value's sum does not affect its final value, though).  What would be a rigorous way to prove it ?


Flex: Database driven DataGrid: arrows disappearing

In Flex I'm using the following code to allow sorting in a DataGrid (the data is paged and sorted serverside).            private function headerReleaseHandler(event:DataGridEvent):void         {             var column:DataGridColumn = DataGridColumn(event.currentTarget.columns[event.columnIndex]);              if(this.count>0)             {                 if(this.query.SortField == column.dataField)                 {                     this.query.SortAscending = !this.query.SortAscending;                 }                 else                 {                     this.query.SortField = column.dataField;                     this.query.SortAscending = true;                 }                 this.fill();             }              event.preventDefault();         }    This works perfectly, except that the arrows that indicate sorting isn't shown. How can I accomplish that?  Thanks! /Niels


how to get player heads on xbox one 1.14.6

So I am making a map for DanTDM, Logdotzip, etc. and my family. I am only 12 and I have no idea how to do advanced commands I only know basics. So I was wondering how you get player skulls on 1.14.60. I tried this command, /give @p minecraft:skull 1 3 {SkullOwner:Logdotzip} and others but it didn't work. I am on bedrock.


Show that a function from a Riemann Surface $g:Y\to\mathbb{C}$ is holomorphic iff its composition with a proper holomorphic map is holomorphic.

I'm trying to show the following:  Let $f:X\to Y$ be a proper holomorphic map between connected, non-empty Riemann Surfaces. Show that a map $g:Y\to\mathbb{C}$ is  holomorphic if and only if  its composition with f is holomorphic.  So far I know that $f$ is surjective, since it's proper and holomorphic. My next step was to look at the charts, but it's there, I get stuck.


Can we make a Vpn server run on Android?

Can we make a Vpn server run on Android. Can applications do this? If yes, which protocols are supported and is this a good idea to use such apps? If not, what are some issues that we may face?


I want to be a Telnet Server, but i couldn't troubleshooting that why other computer on my LAN couldn't connect to me. I went these same steps on other computers but there were no problems to connect them and i can telnet to them. 1) i turned Telnet Client and Telnet Server features from "Control Panel\All Control Panel Items\Programs and Features" 2) then i enabled TELNET service from Services.msc and set that to Automatic. 3) also i enabled Telnet Server option from "Control Panel\All Control Panel Items\Firewal\Advanced settings (Inbound Rules)" and allowed the connection. 4) so i started Telnet Server service from CMD using "net start telnet"  then i tried to connect my Telnet Server from other LAN Computers. but it said:   Connecting To 192.168.1.103...Could not open connection to the host, on port 23:  Connect failed   How can i Fix this problem ?  I'm using Windows 7 and Avast! Anti-virus and Avast! internet security.  note: I did these same steps on another LAN computers , so i could connect to them.


Steam missing the following 32-bit libraries : libc.so.6

I installed Steam through the Ubuntu Logitec and got the following messages:     You are missing the following 32-bit libraries, and Steam may not run:   libc.so.6   Some people advised in previous threads to download through the  and I did but it remains the same.   I am not familiar with Ubuntu yet so pardon my basic question.  Processor:  Graphic card:  OS:


I wanted to report a small UI bug on the iOS app.  Yesterday I was answering a question () in the iOS app, and in the meantime I was typing my answer the question got closed by a user.  I didn't receive the usual warning you have on the web version while you type and the question got closed, and I was able to submit my answer. I found it was already closed after I clicked Submit, as the iOS app shows you the question after.  I double checked today with another question, and if the question is already closed the iOS app does not offer me the option to add an answer (and my mobile browser does not allow me either).  Is it a wanted behavior from the iOS app?   App version: 1.6.6.2 Device: iPhone 5s (GSM) OS version: Version 10.3.2 (build 14F89)


How can a "proper" function have a vertical slope?

Plotting the function $f(x)=x^{1/3}$ defined for any real number $x$ gives us:   Since $f$ is a function, for any given $x$ value it maps to a single y value (and not more than one $y$ value, because that would mean it's not a function as it fails the vertical line test). This function also has a vertical tangent at $x=0$.   My question is: how can we have a function that also has a vertical tangent? To get a vertical tangent we need 2 vertical points, which means that we are not working with a "proper" function as it has multiple y values mapping to a single $x$. How is it possible for a "proper" function to have a vertical tangent?  As I understand, in the graph I pasted we cannot take the derivative of x=0 because the slope is vertical, hence we cannot see the instantaneous rate of change of x to y as the y value is not a value (or many values, which ever way you want to look at it). How is it possible to have a perfectly vertical slope on a function? In this case I can imagine a very steep curve at 0.... but vertical?!? I can't wrap my mind around it. How can we get a vertical slope on a non vertical function?


Union of two Dictionaries to Dictionary>

I want to find a union of two dictionaries, that may contain the same keys, but different values. If key exists in both dictionaries, then I want to merge the values (if they differ) into list. If key exists in only one dictionary, then I want to create a List and add that item to it. So, for example: var dict1 = new Dictionary<int, string>(); var dict2 = new Dictionary<int, string>();  dict1.Add(1, "a"); dict2.Add(1, "b"); dict1.Add(2, "c");  var resultDict = Combine(dict1, dict2);  Result dictionary will be the type of Dictionary<int, List>, and will contain { 1: ["a", "b"], 2: ["c"]}. The simplest solution I can think of, is to traverse union of keys and add empty lists, then traverse both dictionaries and add all values to list for given keys. Is there any good, functional solution to combine these two Dictionaries?


NullPointerException when accessing Boolean Java

I have a boolean which checks if an action is to be performed or not, the boolean is being being accessed through setters and getters, I have other booleans am accessing in a similar way and they are not giving me any errors except this one, at first I was checking it in a piece of code within a seperate thread and that part was not working without producing an exception so I put it in a toggleButton just to do a simple read and write on it, then the nullPointerException came up, here is my code I have commented it  toggleButton.setOnMousePressed(new EventHandler<MouseEvent>() {         @Override public void handle(MouseEvent event) {          //this part is executing perfectly          //meaning my toggleButton is ok          System.out.println("Toggle Button Clicked");           //this is where I am getting the NullPointerException          if(!getblackAndWhite()){              setblackAndWhite(true);           }else{                setblackAndWhite(false);            }         }});   private void setblackAndWhite(Boolean blackAndWhite)  {     this.blackAndWhite = blackAndWhite; }  private Boolean getblackAndWhite() {     return this.blackAndWhite; }


"count noun" or "non-count noun" -- how to know the difference?

The book English Grammar: Understanding The Basics makes the following declaration:     If you can use many with a noun (when it is pluralized), it’s a count   noun. If you can use much with a noun, it’s a noncount noun.   and elsewhere, it says:     If you can use fewer with a noun (when it is pluralized), it’s a count noun. If you can use less with a noun, it’s a noncount noun.   Consider this example: "I have less high schools in my area than in your area." According to the grammar rules above, high schools is a noncount noun but, far as I know, it is a count noun.


Input across RC circuit is not showing a square wave though the input is a square wave

I wanted to observe the transient response of the capacitor so applied a square wave of 205mHz from a function generator as that would allow complete charging and discharging for the capacitor in the circuit below (results came as they were expected), but to compare the difference in input and output signal when i placed the second probe of the oscilloscope across the input it gave the weird waveform below instead of a square wave. Any reason for that ?  R=1 k ohms, C = 470 uF , f = 205 mHz


Can I use my laptop as a second monitor?

Is it possible to make my laptop's screen act as a second monitor for my desktop computer?


continuum, cofinality must be uncountable

How does it follow from $\kappa < \kappa^{cf \kappa}$ that continuum $2^{\aleph_0}$ cannot be $\aleph_{\omega}$?   It is mentioned everywhere that it is obvious.


Why define $\bigcup_{n\in I} A_n=\emptyset,\bigcap_{n\in I} A_n=\Omega$ when $I$ is the empty set

In the textbook I used on Probability and measure theory, a definition catches my eye:  If $I=\emptyset$, we define $\bigcup_{n\in I} A_n=\emptyset,\bigcap_{n\in I} A_n=\Omega$  I didn't draw attention to this definition initially, but this definition puzzles me a lot now. I don't get what it means to map an empty index set to a collection of a subset of $\Omega$. I also don't understand why the author would bother talking about the scenario where the index set is empty.


Some broad|O/T questions on StackOverflow belong on Programmers, but P.SE is prohibitive

I began reading through much of the Meta.SO posts on the subject, notably .  On a daily basis, questions such as the ones below are asked on StackOverflow, many of which are are (for good reason) flagged as "too broad" or "off topic".          These are only a handful of thousands like this. Several of these 'broad' questions may be better suited to be asked on , while others are still too ("immature"?) for P.SE. So much so, that .  Question 1   Is there a more suitable forum for new programmers to get generic or beginner help? I have scoured  for any mention of such a SO site, but to no avail.   Question 2  While many of the aforementioned questions may belong on programmers, the community there is prohibitive to intentionally subjective questions, despite being intended for "conceptual questions about software development".    Do SO's policies support helping the OP re-word their question properly so it can be migrated to it to P.SE? Usually subjective questions are flagged and put on hold before this can even be suggested.   Question 3   It has been debated (endlessly) why or why not some subjective questions are allowed to pass through. Can anyone reference specific posts/conversations that discuss establishing a SE site for subjective and/or beginner programming questions?


I need step by step guidence to recover grub

Yesterday I removed some two tiny partions from the disk,today it won't boot. I opened my computer from USB now, but I can not install grub from chroot. I run sudo blkidand I noticed that my ubuntu installed partition moved from sda6 to sda5.  First  I ran sudo mount  /dev/sda5 /mnt then  sudo grub-install --root-directory=/mnt /dev/sda5 but I got the following error.   /usr/sbin/grub-bios-setup: warning: File system `ext2' doesn't support embedding.  /usr/sbin/grub-bios-setup: warning: Embedding is not possible.  GRUB can only be    installed in this setup by using blocklists.  However, blocklists are UNRELIABLE and their   use is discouraged..  /usr/sbin/grub-bios-setup: error: will not proceed with blocklists.   Would you please tell me what to do now?


POST:- is used to create and update resources PUT:- is used to update existing resources  Can I use POST instead of PUT method? and If I use POST method over PUT method, what will be disadvantages?  If POST can do work of PUT method, why PUT method is required?


Show that if all row-sums of a square matrix $A$ are equal to $0$, then $A$ is singular

I need to show that if all row-sums of a square matrix $A$ are equal to $0$, then the matrix is singular.  My idea was that to represent the situation, I can do as follows:  $$A\vec{x} = \vec{0}$$  and let $\vec{x} = \vec{u} = \begin{pmatrix} 1_1 \\ 1_2 \\ \vdots \\ 1_n\end{pmatrix}$, since   $$\begin{pmatrix} a_{11} & a_{12} & \cdots & a_{1n} \\ a_{21} & a_{22} & \cdots & a_{2n} \\ \vdots & \ddots \\ a_{n1} & a_{n2} & \cdots & a_{nn} \end{pmatrix} \begin{pmatrix} 1_1 \\ 1_2 \\ \vdots \\ 1_n\end{pmatrix}  = \begin{pmatrix} 0_1 \\ 0_2 \\ \vdots \\ 0_n\end{pmatrix}$$ which would mean that the null-space of $A$ is non trivial (i.e. it contains other objects rather than just the $\vec{0}$), in fact it contains also $\vec{u}$.  Does this fact alone proves what I wanted to prove?


Young Adult novel set in underwater city

This is my first post, so I hope I have this set out correctly.  I'm looking to identify a story that I read many years ago, probably written in late 70's or early 80's.  The main points I can remember are below but the plot concerned a young boy/man and an attempt to destroy an undersea city or habitat.  The main protagonist was the son of a diplomat and came from somewhere with lower than normal gravity, I recall one of the early scenes in the book with the boy swimming to build his leg muscles and a girl being in the pool when he arrives.  They talk and she tells the boy about the underwater city she lives in.  As earth gravity made the boy weak, his father sends him to the underwater habitat that the girl lives in, and once there he becomes involved in various adventures, discovering men with artificial gills and other elements that I can no longer remember.  I think the overall plot was to bring down the Earth government by destroying the habitat in an explosion.  Can anyone help identify the story?


I have an array  $DATA = array( array(     "id" => "23",     "rate" => "4.555" ), array(     "id" => "12",     "rate" => "4.555" ), array(     "id" => "20",     "rate" => "4.555" ),  array(     "id" => "29",     "rate" => 5.1025" )    );   Now i need to sort above array by key: rate (ascending) and id (ascending).  So:      function mySort($a, $b) {        return strcmp($a['rate'], $b['rate']);       }   uasort($DATA,'mySort');   Now sort perfect but only by rate....  Adding new funcion:  function mysortID ($a,$b){ //AD         return ($a['id'] > $b['id']) ? 1 : -1;       }   Let's try:    uasort($DATA,'mySort');  uasort($DATA,'mySortID');   But doesn't work.... how to that ?


When the user enters several names, I would like to break only if the user enters the value end.   I am trying this but it doesn't work.  Scanner sc = new Scanner (System.in);      String name = "";      while(name != "end"){       System.out.print("Enter name : " + name);       name = sc.next();       if (name == "end") {      break;      }    }


Connecting GSM SIM900A module with Ardunio

I have bought an SIM900A Mini V4 GSM module. Here is the module,   I want to configure with arduino to send and receive SMS.   Do I have to connect TXD of this module--Tx of Arduino & RXD of this module--Rx of Arduino or other way around?  There is no datasheet or documents on this new module.  When I search about RXD & TXD, I found this in      TxD means "Data to be transmitted over the comms link" - which will clearly be an input to the modem;    Similarly, RxD means "Data that has been received from the comms link" - which will clearly be an output from the modem.    But I couldn't send or receive SMS using this configurations.  As I am new to this, It would be very helpful if anyone help on this.  Thank you in advance.


Rule for if a verb can take -ing (simple present vs present cont.)? eg. I love vs I am loving

As a BrE. speaker, there are come constructions using verbs in their present continuous form which just sound wrong. The best example being, "I am loving Stack Exchange."  After reading around the internet, all the information I can find seems to be addressing the difference in usage and meaning between -ing and infinitives such as "he went on to sing the National Anthem" and "he went on singing..."  Is there a rule as to which verbs can or should be used in a continuous form "I am drinking tea" and those which shouldn't, "I am loving this tea so much right now*"  Thanks  *In a thick Californian accent!


do you multiply the 120 V ac with same DC 2500 mAh ?

I have 2500 mAh on the battery and 3.7 V normal voltage and I get 55 watts for the pack in DC, then after changing my voltage to 120 AC, how can I calculate the wattage? I mean multiply the 120 V ac with same DC 2500 mAh on the battery? point is does it change? the mAh on the battery ?


What does it mean that a function is uniformly continuous? (Geometrically)  I have this definition but i dont understand the definition geometrically. Can someone help me to understand this?  Let $D\subseteq\mathbb{R}$ and $f:D\rightarrow\mathbb{R}$, $f$ is uniformly continuous if $\forall\epsilon>0$ exists $\delta>0$ such that $\forall x,y\in D$ and $\text{|x-y|<}\delta$ then $|f(x)-f(y)|<\epsilon$


Looking for short story about martians coming to earth and 1 of them helping them colonize it again?

I don't remember the exact title, but it was part of a book of short stories, some of which I am also looking for. Its title was along the lines of 'My name is Devil', or 'I am Devil/Satan'.  Basically, a small Martian expedition travels to Earth after a great plague/war occurred, and the Martians don't find much. The Martians speak telepathically, too.  They leave one behind, who resides in a cave. He eventually finds a boy, and I think he has to touch the alien to speak with him, and the kid tells the Martian  'you're a devil'.  The kid and Martian eventually travel with a sled-toboggan type floating vehicle to an old man, who explains to the Martian how some kind of virus wiped them all out. They start a colony, where they find many different kinds of people.  I believe years pass, and the virus comes back. people leave, but the alien and I think the infected human go away for a few days, and both return, healthy again.  In the ending, the Alien goes to hibernation, that apparently happens to all of the Martians. A second Martian expedition arrives, and are surprised to see the thriving colony. The boy from the beginning meets them, tells them his name, and asks them when will the original Martian wake up.  The Martians go inside, and announce he will be waking up soon.


Java/JCE: Decrypting "long" message encrypted with RSA

I've got a message contained in an byte[], encrypted with "RSA/ECB/PKCS1Padding". To decrypt it I create a Cipher c and initiate it with  c = Cipher.getInstance("RSA/ECB/PKCS1Padding");   Untill now I have only decrypted small messages, using the doFinal() method, returning an byte[] with the decrypted bytes.   c.init(Cipher.DECRYPT_MODE, privateKey); byte[] decryptetBytes = c.doFinal(encryptedBytes);   But in this case the data is bigger (approx 500 Bytes), and the doFinal()-method throws an exception (javax.crypto.IllegalBlockSizeException: Data must not be longer than 128 bytes). I guess I need to use the update()- method, but I can't figure out how to get it to work properly. How is this done?


bound on the cardinality of the continuum? I hope not

Suppose we don't believe the continuum hypothesis. Using Von Neumann cardinal  assignment (so I guess we believe well-ordering?), is there any "familiar" ordinal number $\alpha$ such that, for non-tautological reasons, $\aleph_\alpha$ is provably larger than the cardinality of the continuum? I would hope not since it would seem pretty silly if something like $\alpha = \omega_0$ worked and we could say "well gee we can't prove that $c = \aleph_1$, but it's definitely one of $\aleph_1, \aleph_2, \ldots , \aleph_{73}, \ldots$". I (obviously) don't know jack squat about set theory, so this is really just idle curiosity. If a more precise question is desired I guess I would have to make it     For any countable ordinal $\alpha$ is the statement: $c < \aleph_\alpha$ independent of ZFC in the same sense as the continuum hypothesis?   assuming that even makes sense. Thanks!


Biblatex - bibliography sectioning and numbered list of references

I am using Biblatex and sectioning my references into two different sections like this:  \printbibliography[type=book,title={Books}] \printbibliography[type=misc,title={Miscellanous}]   This works fine, except for the fact that the book section is not numbered the way I want it, I want it to start with '1' and then the next ones '2', '3',... This is how it looks like right now:


Why does include with brackets not find the header file?

I have a header file DCM_Types.hh which is in fact located in the project directory. Why cannot find the source file?


I have this doubt when it comes to sports and teams.  Is it England is playing or England are playing? Similarly, is it "Arsenal is playing..." or "Arsenal are playing..."?


Should my foot be able to step flat on the ground, when I sit on a bike seat?

I was wondering, for a correctly sized mountain bike, or hybrid, should I be able to place my foot flat on the ground, when I sit on the bike seat?


$|(z_0-w_1)...(z_0-w_n)|=1$ for some $z_0$ in the unit disk

Let $\mathbb{D}=\{z\in \mathbb{C} \,\,|\,\,|z|<1\}$. Prove that, if $\{w_1, \,...\,,w_n\}\subset\mathbb{D}$, then there exists a point $z_0\in \mathbb{D}$ such that:  $$|(z_0-w_1)...(z_0-w_n)|=1$$  [Hint: use the Cauchy inequalities or the maximum modulus principle]   My idea initially was to prove, somehow, that $\exists\alpha\in\partial\mathbb{D}$ with $|P(\alpha)|>1$, where $P(z)=(z-w_1)...(z-w_n)$. If that is true, than from the maximum modulus principle:  $$\sup_{z\in\mathbb{D}}|P(z)|=\max_{z\in\partial\mathbb{D}}|P(z)|>1$$  That means $|P(\beta)|>1$ for some $\beta\in\mathbb{D}$ close enough to the border. Since $|P(0)|=|w_1|...|w_n|<1$ and |P| is continuous, from the intermediate value theorem, $|P(z_0)|=1$ for some $z_0\in\mathbb{D}$.  But I'm having trouble to prove that such $\alpha$ exists. Any ideas?  Thanks!


Over the last few days I have been observing a feature of Stack Overflow, namely “CLOSE”, through which a question can be closed to answers.  In my observation I have found that there are many questions which are closed within 10-20 minutes from the time of asking. Some of these questions have upvotes, and have answers as well, and the answers also have upvotes.  According to the rules, if a question gets five close votes, that question will be closed immediately. Here's what I'm worried about:  If five users vote for closing, that question will be closed immediately. At the same time, if other users want to give an answer to that question, they can’t because the question is closed.  In that scenario, it does not make sense to close that question immediately.  Users who vote for closing the question give reasons like: this question cannot be answered, it is vague, etc., etc.  My suggestion is that a question should not be closed immediately. There should be a one hour time limit. If a question has five close votes, then this question should be closed after one hour, not before that. If some users think that this question can be answered, in my scenario one hour would be sufficient for them to answer.  If you community members still think that closing a question immediately is right, then my suggestion is the question should be deleted, not closed. If a question cannot be answered or is vague, it does not make sense to keep the question only for viewing. It is a loss of time and space.  Sometimes closing a question immediately hurts the feelings of the user who has asked the question.  So now I would like to know your opinion on the follow two suggestions:    Question should be close after 1 hour. Question should be deleted instead of closed.


I created a script ./abc.  I want to break the ouput into new lines.  mycode:  #!/bin/bash dir="$1"  echo -n "size of file:" du -hba $dir | sort -n -r | tail -1   my output is:   size of files: 20kb /path/to/sport   I want the output as:  size of files: 20kb          /path/to/sport


Regex in vb.net get all A elements in a string

Say I have a string consisting of HTML, in a string Dim HtmlString as string = "bla bla bla blala bla22"  I need to get an array of string containing all the A elements found in the HtmlString say Dim AElementsInHtmlString as String()  How can I get ?


C++ how to handle alignment padding when casting raw data to class objects

I read big sections of a file as "blobs" of data to char arrays. I know how these blobs are structured, and have created classes for the different structures. Then I want to cast the read char arrays to arrays of appropriate class objects.  This has worked well for certain cases, but I have gotten to a case where alignment / padding of the class members is an issue.  Here is a minimal example, but instead of getting data from a file, I define the data in data_i1, data_d1 and data_i2, then cast it to c_data.  c_data represents the data read from the file and contains data_i1, data_d1 and data_i2 twice.  Without alignment being a problem, if I cast c_data to and array of Data, I should get the initial data in Data[0] and Data[1].  #include <iostream>  class Data { public:     int     i1[2];     double  d1[3];     int     i2[3]; };   int main() {     //Setting some data for the example:     int     data_i1[2] = {  1,   100};          //2 * 4 =  8 bytes     double  data_d1[3] = {0.1, 100.2, 200.3 };  //3 * 8 = 24 bytes     int     data_i2[3] = {  2,   200, 305   };  //3 * 4 = 12 bytes                                                 //total = 44 bytes      //As arrays the data is 44 bytes, but size of Data is 48 bytes:     printf("sizeof(data_i1) = %d\n",    sizeof(data_i1));     printf("sizeof(data_d1) = %d\n",    sizeof(data_d1));     printf("sizeof(data_i2) = %d\n",    sizeof(data_i1));     printf("total size      = %d\n\n",  sizeof(data_i1) + sizeof(data_d1) + sizeof(data_i2));     printf("sizeof(Data)    = %d\n",    sizeof(Data));       //This can hold the above that of 44 bytes, twice:     char c_data[88];      //Copying the data from the arrays to a char array     //In reality the data is read from a binary file to the char array     memcpy(c_data +  0, data_i1,  8);     memcpy(c_data +  8, data_d1, 24);     memcpy(c_data + 32, data_i2, 12); //c_data contains data_i1, data_d1, data_i2     memcpy(c_data + 44,  c_data, 44); //c_data contains data_i1, data_d1, data_i2 repeated twice      //Casting the char array to a Data array:     Data* data = (Data*)c_data;      //The first Data object in the Data array gets the correct values:     Data data1 = data[0];     //The second Data object gets bad data:     Data data2 = data[1];      printf("data1 : [%4d, %4d] [%4.1f, %4.1f, %4.1f] [%4d, %4d, %4d]\n", data1.i1[0], data1.i1[1], data1.d1[0], data1.d1[1], data1.d1[2], data1.i2[0], data1.i2[1], data1.i2[2]);     printf("data2 : [%4d, %4d] [%4.1f, %4.1f, %4.1f] [%4d, %4d, %4d]\n", data2.i1[0], data2.i1[1], data2.d1[0], data2.d1[1], data2.d1[2], data2.i2[0], data2.i2[1], data2.i2[2]);      return 0; }   The code output is:  sizeof(data_i1) = 8 sizeof(data_d1) = 24 sizeof(data_i2) = 8 total size      = 44  sizeof(Data)    = 48 data1 : [   1,  100] [ 0.1, 100.2, 200.3] [   2,  200,  305] data2 : [ 100, -1717986918] [-92559653364574087271962722384372548731666605007261414794985472.0, -0.0,  0.0] [-390597128,  100, -858993460]   How should I correctly handle this? Can I somehow disable this padding/alignment (if that is the right term)? Is it possible to create a member function to the class to specify how the casting is done?


How many functions are possible to create in this example?

Let $A = \{ 1,2,3,4 \}$ Let $F$ be a set of all functions from $A \to A$.  Let $S$ be a relation defined by : $\forall f,g \in F$ $fSg \iff f(i) = g(i)$ for some $i \in A$  Let $h: A \to A$ be the function $h(x) = 1 $ for all $x \in A$.   How many functions $g \in F$ are there so that $gSh$ ?  My solution : $gSh$ means that $g(i) = h(i)$ for some $i \in A$. So $g(i) = 1$.  So number 1 always needs to connect to some x - 4 choices.  Then we have $3$ left-over numbers that can connect to $4$ numbers each.  So solution is $4 \cdot 4 \cdot 4 \cdot 4$. Is this correct at all? Thanks in advance !! :)


how to read specific values from text file using c++?

I have a textfile as follows:  Value1 = windows Value2 = Processor Value3 = pwower plug   Right now i am retrieving complete file as follows:  std::ifstream myfile; myfile.open( "D:\\values_user.txt", std::ios::in );  if( !(myfile.is_open()) ) {   std::cout << "Error Opening File"; std::exit(0);   }  std::string firstline;   while( myfile.good() ) {     std::getline( myfile, firstline);     std::cout<< "\n" << firstline <<"\n"; }   I want to  retrieve window, processor and pwower plug i.e. just want to have values after '='. So, suggest me how can i achieve this.


I updated android studio and it seems that something went wrong  Internal Error. Please report to https://code.google.com/p/android/issues  com.intellij.ide.plugins.PluginManager$StartupAbortedException: java.lang.reflect.InvocationTargetException     at com.intellij.ide.plugins.PluginManager$2.run(PluginManager.java:96)     at java.lang.Thread.run(Thread.java:745) Caused by: java.lang.reflect.InvocationTargetException     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)     at java.lang.reflect.Method.invoke(Method.java:498)     at com.intellij.ide.plugins.PluginManager$2.run(PluginManager.java:93)     ... 1 more Caused by: java.lang.NoClassDefFoundError: io/netty/channel/ChannelHandler     at com.intellij.idea.SocketLock$2.call(SocketLock.java:154)     at com.intellij.idea.SocketLock$2.call(SocketLock.java:128)     at com.intellij.idea.SocketLock.underLocks(SocketLock.java:191)     at com.intellij.idea.SocketLock.lock(SocketLock.java:128)     at com.intellij.idea.StartupUtil.lockSystemFolders(StartupUtil.java:318)     at com.intellij.idea.StartupUtil.prepareAndStart(StartupUtil.java:140)     at com.intellij.idea.MainImpl.start(MainImpl.java:34)     ... 6 more Caused by: java.lang.ClassNotFoundException: io.netty.channel.ChannelHandler     at com.intellij.util.lang.UrlClassLoader.findClass(UrlClassLoader.java:207)     at java.lang.ClassLoader.loadClass(ClassLoader.java:424)     at java.lang.ClassLoader.loadClass(ClassLoader.java:357)     ... 13 more   I want to remove it completely from my laptop


I can't remember my passcode and I have Find my phone app turned on my phone is disabled and says connect to itunes but it wont let me restart my phone as i have find my phone app turned on i have deleted my find my phone account in hope it would fix it but it didnt and  now i cant get it working at all what should I do? :( and it also wont let me connect to the wifi or data as it is disabled.(IPhone 4s)


How to install OpenLayers plugin in QGIS1.8

I am using QGIS 1.8.0 on Windows 7 (32-bit) but am unable to install the OpenLayers plugin.  The Python plugins menu does not include OpenLayers on the plugin list.  Can it be somehow added manually?


Potential energy of an infinitesimal length of elastic rod

I am having an embarrassingly hard time with the derivation for the potential energy of an infinitesimal element of an elastic rod of area $A$. The picture shown below is an element of the rod that has been extended by $du$ by the force $F$.        I've tried this derivation several times and have yet to obtain the factor of $\frac{1}{2}$ in      $$dU=\frac{1}{2}AY\big(\frac{du}{dx}\big)^2dx,\tag{1} $$    which is given in my lecture notes. Here is my best attempt so far: From the stress strain relation, $\sigma=Y\epsilon$, where $Y$ is Youngs modulus we obtain:  $$\frac{F}{A}=Y\frac{du}{dx}.\tag{2} $$  I asked a  a few days ago, and based on that response I've assumed that the work done in extending the rod element from length $dx$ to $du+dx$ is   $$dW=F\big[ (du+dx)-dx\big]\tag{3}  $$  $$=YA\frac{du}{dx}du.\tag{4} $$  And I can make it look more like the answer given in my lecture notes if I divide and multiply by $dx$:  $$dW=YA\big(\frac{du}{dx}\big)^2dx.\tag{5}$$  And I am assuming that $dW=dU$ here ($F=-\frac{dU}{du} $ but forget about the negative sign)  I have tried other approaches but they make even less sense to me. A formula that I think will come in handy is the deflection at section x of a rod:   $$\delta(x)=\frac{F}{AY}x ,\tag{6}$$   and I think an integral will come in to play but I'm not sure what I'm integrating over any more (I'm dealing with an infinitesimal element of the rod). So how do I use the infinitesimal Work to find the infinitesimal change in potential energy here to get that factor of $\frac{1}{2}$ (assuming that it does in fact belong in $dU$)?


How do I remove default comment validation in drupal 7?

Drupal is showing error message for empty comments by default. how can i remove that error message. Note:- (I have not written any custom validation. It's the default validation provided by drupal module.) My changes in comment.module  if (empty($comment->cid) && empty($comment->pid)) {  if(($form['#node']->type=='iks_videos_youtube_video') || ($form['#node']-               >type=='iks_videos_vimeo_video' || $form['#node']->type=='iks_videos_video')){ if(isset($form['#node']->type) && $form['#node']->type=='iks_videos_youtube_video') {   $vtype='yt';} else {   $vtype='v'; } $form['#action'] = url('video/' . $form['#node']->video_id[LANGUAGE_NONE][0]['value'] . '/'.$vtype.'/' . strtolower(str_replace(' ', '_', $form['#node']->title)));   }else{ $form['#action'] = url('comment/reply/' . $comment->nid);}   }  my custom module code  function  iks_videos_form_comment_node_iks_videos_youtube_video_form_alter(&$form, $form_estate) { if (isset($form['actions']['preview'])) unset($form['actions']['preview']); $form['subject']['#access'] = FALSE; unset($form['author']['mail']['#description']); $form['#submit'][] = '_iks_videos_comment_form_submit';     }   alter form  function _iks_videos_comment_form_submit($form, &$form_estate) {  if(($form['#node']->type) && $form['#node']->type=='iks_videos_youtube_video')     $vtype='yt'; else      $vtype='v'; $form_estate['redirect'][0] = 'video/' . $form['#node']->video_id[LANGUAGE_NONE][0]['value'] . '/'.$vtype.'/' . strtolower(str_replace(' ', '_', $form['#node']->title));   }


I'm trying to setup my iMac running 10.6 to be a wireless bridge. I have it working, but I need to disable DHCP and let my network's DHCP server provide an IP for the connected device(s). I can't seem to find a way to disable DHCP in Internet Connection Sharing. Does anyone know if this is possible? I'm guessing there's a key one could set in /Library/Preferences/SystemConfiguration/com.apple.nat.plist, but I can't find it. I checked the man page for InternetSharing and it doesn't mention anything useful, except changing the subnet that the DHCP server uses.


What's the difference between 'why would you do that' and 'why did you do that'?

What's the difference between      Why would you do that?   and      Why did you do that?   I always saw the sentence 'why would you do that' while watching movies. Why they prefer to use the word 'would'?


Generalized rotation matrix in N dimensional space around N-2 unit vector

There is a 2d rotation matrix around point $(0, 0)$ with angle $\theta$.  $$ \left[ \begin{array}{ccc} \cos(\theta) & -\sin(\theta) \\ \sin(\theta) & \cos(\theta) \end{array} \right] $$  Next, there is a 3d rotation matrix around point $(0, 0, 0)$ and unit axis $(u_x, u_y, u_z)$ with angle $\theta$ ().  \begin{bmatrix} \cos \theta +u_x^2 \left(1-\cos \theta\right) & u_x u_y \left(1-\cos \theta\right) - u_z \sin \theta & u_x u_z \left(1-\cos \theta\right) + u_y \sin \theta \\ u_y u_x \left(1-\cos \theta\right) + u_z \sin \theta & \cos \theta + u_y^2\left(1-\cos \theta\right) & u_y u_z \left(1-\cos \theta\right) - u_x \sin \theta \\ u_z u_x \left(1-\cos \theta\right) - u_y \sin \theta & u_z u_y \left(1-\cos \theta\right) + u_x \sin \theta & \cos \theta + u_z^2\left(1-\cos \theta\right)  \end{bmatrix}  How it is possible to generalize rotation matrix on $N$ dimension around zero point and $N-2$ dimensional unit axis with angle $\theta$?


Difference between limit and limit point

My question is that ,what is the diffrence between limit and limit point?


Finitely generated monoids - how to show that there is not first order set axiomatizing them.

Let $\mathbb{M}=\langle M,\circ, e\rangle$ be a monoid. We say that   $\mathbb{M}$ is finitely generated when there exist finitely many   elements in $M$ such that each element of $M$ may be generated using   only these elements.         For example, $\langle A^*, \cdot, \epsilon\rangle$ is finitely   generated if only and only alphabet $A$ is finite.   Show that the class of finitely generated monoids is not axiomatized.      I would like to use Ehrenfeucht-Fraissé games to prove it.  I solved some tasks about showing not-axiomatization with these games, however mentioned exercises were about graphs.  So my solutions are based on relations (edges, degrees..). Here, I have no idea which side of this exercise should be attacked by me.     Help me please.  Edit after hints of @Noah Lets suppose that such $\Delta$ exists. Then, lets extend signature by constans: $c_1,c_2,...$ and let $\Delta'=\Delta\cup \Gamma$, where $\Gamma=\{\forall_{x\in A}\forall_{y\in A}x\circ y \neq c_i:i\in\mathbb{N} \}$.  Of course we have infinitely many elements not generated by rest of elements. Using compactness theorem we conclude contradiction. Let $\Delta_0\subseteq\Delta'$ will be finite set. Then it is easy to see that it is satisfable - We can add properly many elements to $A$ generated by nothing and assign to them finitely number of constanst $c_i$.     What do you think about this solution ? If I am wrong, tell me where.


How can I respawn at a specific location after dying?

Whenever I respawn, I will either spawn into my map, or outside. This happens everytime, even when I set the worldspawn to the correct location.  Am I supposed to use the sort of contraption where you can play a title when you die, but instead use it to teleport when they are dead?    I'll be very thankful if you could tell me anything!


Temperature and kinetic energy of molecules

I was wondering if temperature is related to the average translational kinetic energy of the molecules then why does the average kinetic energy of say a moving object not affect the temperature? What is the mechanism regarding these vibrational motions that imparts temperature. Also do a gas and liquid at the same temperature possess the same kinetic energy? and a heavier molecule traveling at the same speed as a lighter molecule will have a greater temperature?


What Are the Current "Fault"and "No-Fault" Closes?

Before the recent change in close/on hold reasons, certain close reasons (e.g. "off topic") would carry an automatic downvote (what I call a "fault" close). Others such as "duplicate," would not (the OP isn't penalized for not realizing his question is a a duplicate, meaning "no fault."  With the new close reasons, which are the "fault" closes (automatic downvote), and which aren't?


Letter class alternatives with support for figures, tables, and labels

I'm increasingly fed up with the arbitrary restrictions that the standard LaTeX letter class has. Today I discovered that the table environment is not defined in the standard letter class, which means one can't use labels or captions.  CTAN has a . Can anyone suggest a good LaTeX letter class to work with for general use? I'd like something as flexible and with as few restrictions as possible, well maintained, not excessively complicated to use, and not buggy. I was earlier recommended newlfm (on comp.text.tex).  was about the fact that the letter class does not allow the addition of a subject.  A similar question has been asked already, , where scrlttr2 is recommended.


Why are the eigenvectors of $A$ orthogonal when $AA^T=A^T A$?

Prof. Gilbert Strang mentions, in , that a matrix $A$ has orthogonal eigenvectors when $A^T A=AA^T$; i.e., when it is normal. Could someone provide me a (preferably intuitive) proof of this?


Let $x\in \mathbb{R^n}$ be a nonzero columns vector. Define $A=xx^T\in  M_n( \mathbb{R})  $. What is the necessary and suffcient condition for $I-2A$ to be an orthogonal matrix?  Should I use $AA^T=I$?


I just began studying electrostatics in university, and I didn't understand completely why the electric potential due to a conducting sphere is  $$   V(\vec{r})=\begin{cases}     \dfrac{1}{4\pi\epsilon_0}\dfrac{Q}{R}, & \text{if $r \le R$}.\\ \\     \dfrac{1}{4\pi\epsilon_0}\dfrac{Q}{r}, & \text{if $r \gt R$}.   \end{cases} $$  Where Q is the total charge and R is the radius of the sphere (the sphere is located at the origin).  I only understand the second part of this equation (when $r > R$).  I know Gauss Law. know the charges go to the surface. I know the electric field strictly inside it must be zero. (I also know the electric field is not defined for a point that lies exactly in the surface). And I know $\vec{E} = -\nabla{V}$.  Therefore, I know the electric potiential inside the sphere must be constant. Let $C$ be this constant.  It seems that  $$ C = \lim_{r \to R^+} V(r) = \dfrac{1}{4\pi\epsilon_0}\dfrac{Q}{R} $$  But why is this true? My textbook says: because the electric potential must be a continuous function. But why? I am hoping for a non-experimental reason.  Please be precise when mentioning $r<R$ or $r\le R$. Those are different and I get easily confused when people misuse those.


QGIS display does not reflect projection

I have slight experience with ArcGIS, but am new to QGIS.  I'm trying to set the projection of my map, and I understand that this is done by altering the CRS (coordinate reference system) of each layer and/or the entire project.  When I right click a layer and select "Change Layer CRS", however, the visual representation of the map (the distortion) does not reflect the selected projection. My world map looks like it has a Robinson (or similar) projection, even if I select a Mercator CRS. The EPSG code in the lower right corner changes, as do the coordinates.    Setting the project CRS to the same projection does not help, nor does enabling on-the-fly projection.  My goal is to export the map to SVG, so the visual distortions are important.  Am I doing something wrong?


Info option is missing from the dropdown on tag pages

When a tag page is visited from mobile site, info option is missing from the dropdown. Mobile site:  Full site:


Zariski closure of some set in an affine scheme

Let $R$ be a ring and let $X = \operatorname{Spec} R$. Let $S$ be a subset of $X$. I want to show that $\overline{S} = V(T)$, where $T = \bigcap_{P \in S} P$. Given any $P \in S$, clearly $T \subseteq P$ so $S \subseteq V(T)$, hence   $\overline{S} \subseteq V(T)$. How can I get the other direction? Thank you!


Assuming Bale twin #1 is the bad-ish one who ties the fatal knot and twin #2 is the meek and gentler one and that Angier met twin #2 both the times when he wanted to know which knot had been tied, why didn't twin #2 lie to Angier?   It's not as if he has sworn to tell the truth throughout his life. Why not tell him he tied the simple knot instead of giving him an annoying and obviously impossible 'I don't know'.


I have two objects A(parent) and B(child) related by a lookup relationship. I  need to update records in object A using data loader. There is an after update trigger on object A which updates some fields on related records of object B. On object B as well there is an after update trigger which updates a field on parent object A. How can i handle recursion.


Pinouts of 4-digit Seven Segment Display!

I have a display as in photo I sent you. But it has no label so I can't get data sheet. It has seven pins only. How to know  its pin  configurations? Please help me.


How would you make an edge circle around a cone?

I tried using the knife tool, which turned out to be a disaster since I have partially paralyzed hands.  I tried loop slide and whatever and it appeared to not do anything.  I tried subdivide and got something I think I can work with but there has to be an easier way.  Can anyone give me a hint or a link to a good basic tips tutorial or anything?


What is the difference between the normal average and weighted average?

What is the difference?For what kind of purpose do we use the weighted average method?Why don't we instead always use the normal average method?and also,how to get the weighted average of some numbers?Also,do we have first to get the mean(normal average) of numbers in order to get their weighted average?  Thank you so much.


So I have just started using tocloft in LaTeX for my report in order to generate a list of equations. The list works fine and it does what I need it to, but the only issue so far is that the heading 'List of Equations' is in much bigger font than the other headings for 'Contents' , ' List of Figures' etc... How can I change this?  Here is the code I have for the list.  \usepackage{tocloft} \newcommand{\listexamplename}{List of Equations} \newlistof{example}{exp}{\listexamplename} \newcommand{\example}[1]{% \refstepcounter{example} \par\noindent\text{Equation \theexample. #1} \addcontentsline{exp}{example} {\protect\numberline{\thechapter.\theexample}#1}\par}


Question about a bijection between $\mathbb R$ and $\mathbb R \cup \{\infty\}$

About a bijection between $\mathbb R$ and $\mathbb R \cup \{\infty\}$  If we'll take a line $f(x)=\begin{cases} ax &, x\in\mathbb R\\ 0 &, x=\infty  \end{cases}$ then we'll have a bijection.   But about this function: $g(x)=\begin{cases} x &, x\in\mathbb R\setminus \{0\}\\ 0 &, x=\infty  \end{cases}$ ? it appears to be a bijection and it's even simpler.


How to make Thunderbird Mail runs at startup?

Is that possible that I can make Thunderbird Mail app runs at the startup or as soon as I log into my Ubuntu? This is my first time using Ubuntu, I create a Dual Boot Ubuntu and I learn about Linux from my Introduction to Linus course at my college. I hope I can learn a lot here about Linux/Ubuntu as I am sick of Windows. Thanks.


Why are assets (images) in Unity build reported as 28 times larger

I'm trying to reduce a Unity WebGL build size which, for the data asset, is currently at 30 Mb.  I installed the .  On clicking the "Source assets" tab and choosing "Size" it showed the top entries were images.  Fine.  But all the sizes reported were between 4 and almost 30 times the size of the file on disk.  Is this just a bug / artifact of the build reporter or a genuine problem which I need to address to reduce the build sizes?  ** Edit **  Two of the files are text files.  Their size in unity build report is the same as that on disk.  Why?    ** Edit 2 - after Ed Marty's answer **  Using low quality with crunch compression at 70 results in slightly lower image quality but it went from 10 Mb to 300 kb, i.e. 30 times smaller size (and about 10x smaller than actual file size on disk).


New to all of this. Which ranges of inner tube would fit in a 29 X 1.4 SLICK MOUNTAIN BIKE TYRE WILD RUN'R? Should I also worry about valve size? If possible, can I have a good source for learning what those numbers mean?


Why is space inserted at beginning of table or figure caption when using macros to define caption label?

Here is my MWE. As you can see, the problem only happens when we use the macro \suppOrApp.  \documentclass{article}  \usepackage[english]{babel} \usepackage{blindtext}  \usepackage{caption} \usepackage{float} \usepackage{ifthen}  \title{A caption test} \author{Some one} \date{\today}   \begin{document}  \newcommand{\suppOrApp}{   \ifthenelse{\boolean{thesisStyle}}     {Appendix}     {Supplementary} } \newboolean{thesisStyle} \setboolean{thesisStyle}{false} % Might want to reconsider this here.   % This has additional space: \renewcommand{\tablename}{\textbf{\suppOrApp Table}} % But this would work fine. %\renewcommand{\tablename}{\textbf{Supporting Table}}   \begin{table} \begin{tabular}{cc} 1 & 2 \\ 3 & 4 \\ \end{tabular} \caption{\blindtext} \label{mytable} \end{table}  \blindtext  Please refer to Supporting Table~\ref{mytable}.  \end{document}


If a function $f$ is holomorphic on the closed unit disk centered at the origin and is real valued whenever $|z| = 1$, then $f$ is constant.

I am preparing for qualifying exams, and this is a question from the Penn State Qualifying Exam for Fall 2015. It is stated as follows  Let $\epsilon > 0$ and let $f$ be holomorphic (analytic) on the disk $S = \{z \in \mathbb{C} \ | \ |z| < 1 + \epsilon \}$. Suppose that $f(z)$ is real valued whenever $|z| = 1$. Prove that $f$ is constant.  I have tried a few things in showing this to be true, but I keep finding holes in my logic. My largest issue is that the portion of the domain in which $f$ is real valued is not open, and so I'm not able to use many of the theorems I otherwise feel would be helpful (Open Mapping Theorem, Cauchy-Riemann Equations, Maximum Modulus, etc.).   Most of my attacks towards this problem have centered around showing things for the unit disk $\mathbb{D}$ instead of $S$, because I figure if I can show that $f$ is constant on $\mathbb{D}$, then I can use the Identity Theorem to extend it to $S$. However, since I don't know anything about the specific values that $f$ obtains, I can't use Schwarz' Lemma either.  I played with the idea, also, of suggesting that, if we consider the closure of $\mathbb{D}$, then $f(\partial{\mathbb{D}}) \in \mathbb{R}$. Since $\partial\mathbb{D}$ is closed and bounded and $f$ is analytic, it's image should also be bounded. That would put, for some $M \in \mathbb{R}$, $f(\partial{\mathbb{D}}) \in [-M,M]$, which is bounded and obtains a maximum (since $f$ is continuous and real valued here). I know that this set isn't open, but there is a Corollary in my text (Complex Analysis - Freitag) that says the following:  "If $K$ is a compact subset of the domain $D$ and $f:D \rightarrow \mathbb{C}$ is analytic, then the restriction of $f|K$ being a continuous function has a maximal modulus on $K$. By the Maximum Modulus Principle, we can moreover affirm that the maximal modulus value is necessarily taken on the boundary of $\mathbb{D}$."  The proof of that statement follows from the Open Mapping Theorem. Would it be appropriate to use that in this case, then? If $K = \partial \mathbb{D}$, even though it's technically not an open set, can I say that $f$ obtains its maximum on $\mathbb{D}$, state that it's constant, and then extend this to $S$ using the Identity Theorem? My issue here is that the constant itself isn't actually in $\mathbb{D}$,  I appreciate any help for this problem (or any tips for showing that complex functions will be constant, as these types of problems show up often).  Edit: My function $f$ is not necessarily entire, so Liouville's Theorem does not apply


Did Nolan leave the ending of Inception up to the audience?

I know that a lot of discussion about this one has taken place already. But as you know its "INCEPTION"! every time you see it, it blows your mind...         So if you see closely you can see that in the last couple seconds of movie the totum trembles and the moment we think its going to fall down Nolan ended the scene. So here, was Nolan trying to suggest that everyone can decide there own version? Either you can think that the totum kept spinning and Cobb is stuck in limbo or the totum stopped spinning and Cobb is really back home.         Any thoughts???


Just how accurate is the frequency of US Wall Outlets?

I have a submersible pump for which I'm trying to determine the variability in flow rate, to high precision. Since this is just an impeller driven by an AC motor, what is the % error in frequency of a US wall outlet? Is there a commonly accepted 'ballpark' value, such as 60 hz +/-0.5 hz?   My suspicion is that for most electrical grids, this largely depends on the citywide usage throughout the day.   I apologize because I have an inkling that my question is poorly presented -- that being said, if anyone knows of where I can find real-time data regarding the West Los Angeles electrical grid, I'm all ears. Thanks!


What is a good texture packing algorithm?  Technically,  is , so a heuristic is what I'm really after.


number of ordered pairs of integers $(x,y)$ satisfying the equation

I need to find the number of ordered pairs of integers $(x,y)$ satisfying this equation:   $$x^2 + 6x + y^2 = 4.$$   I have tried, and I think $x<0 . $  Is there a specific way to solve such equations?


How can I write multiple lines in a subscript?

Is there a way to force a line break inside a math mode text?  My example:  \[   \underbrace{....}_\text{Some long text that should be multiline} \]   Trying  \text{Some long text that\\ should be multiline}   Didn't do the trick.


Query about approaches to extract energy out of Quantum Vacuum Fluctuations

Are we aware of any theoretically sound approach that would potentially allow us to extract energy out of the Quantum Vacuum Fluctuations indefinitely.  The magnitude of the energy extracted doesn't matter, just the soundness of the approach (not just speculation) based on our current knowledge.  For example (Specifically): Why can't we use Static Casimir Effect to do it?


passing parameter from one batch apex into another batch apex

I want to know whether it is practically possible to pass a parameter from first batch apex into second batch apex. I do not want code but a brief concept would be greatly helpful.


how to move specific files based on their extensions

I want a command that allows to select specific files based on their extensions to move them to another directory.


$$\mu = \sum\limits_{k=0}^{\infty}\dfrac{2^{k}}{\displaystyle{2k+1 \choose k}}$$  The answer is $\dfrac{\pi}{2}$. But I don't know how to do it. Please show me the way! Thank you.


On a linux system what is the purpose of the .profile file I know a small amount on this topic but I need an explanation of the purpose of the .profile file and a explanation of the contents.


Show that space of all linear transformations from $V \to V$ is a vector space

Show that space of all linear transformations L(V,V) from $V \to V$ is a vector space.   Vector spaces have 8 characteristics that describe them as vector spaces. Therefore, I think that to check if $L(V,V)$ is a vector space I need to check if it meets all the points.  Take as the basis of $V$ $t_1,t_2,...,t_n$  1) Given any two transformations $T:V \to V$ and $U: V\to V$ we must show that for any $v \in V$ $T(v) + U(v) \in L(V,V)$.  Since $T: V\to V$ $\exists v_1 \in V$ such that $T(v) = v$. The same for $U: V\to V$ $\exists v_2 \in V$ such that $U(v) = v_2$. Therefore, $T(v) + U(v) = v_1 + v_2$. Since $V$ is itself a vector space, then $v_1+v_2 \in V$, so $T(v) + U(v) \in V$. Also we have that $T(v) + U(v) = (T+U)v$ is linear. Therefore, $T(v) + U(v) \in L(V,V)$.  2) Given any transformation $T:V \to V$ and $a \in K$ we must show that for any $v \in V$ $kT \in L(V,V)$.   For any $v \in V$. Since $T: V\to V$ $\exists v_1 \in V$ such that $T(v) = v_1$. Since $T$ is a linear transformation by default then $kT(v) = kv_1$. Since $V$ is itself a vector space then $kv_1\in V$. Hence, $kT \in L(V,V)$.  3)  Given any two transformations $T:V \to V$ and $U: V\to V$ we must show that for any $v \in V$ $T(v) + U(v) = v_1 + v_2$ and $U(v) + T(v) = v_2 + v_1$. Since $v_1 + v_2 = v_2 + v_1$ because of $V$ being linear space $T(v) + U(v) = U(v) + T(v)$  I guess, the other points will be done in a similar manner. Is this approach right? Are there any mistakes in the logic?


What is the grammar used in this sentence

“Love is too weak a word for the way I feel.” Can anyone explain to me what the grammar behind “too weak a word” is? Specifically the usage of ‘a’


Is it worth going to an academic conference if I'm just attending?

There's a maths conference coming up and the whole thing amounts to about $1K, which is not the problem. I'm not going to be presenting, and I'm just going to be attending. I am planning to go next year to present a project I've currently started. Is it worth going this year?   Thanks!


Mail.app how to archive messages with delete key?

Recently I have noticed that Mail.app on Mojave is sending discarded messages to the trash instead of archive.  I have set the preference "Move discarded messages into archive", but that doesn't seem to make a difference.  The user guide says this setting is for swip guestures, but I was hoping it would apply to the delete key as well.   On the toolbar, I have two separate buttons for Delete and Archive.  Both of these buttons work correctly, but I like to discard messages using the delete (backspace) key.  I did figure out that setting Trash Mailbox to None will effectively make all discarded messages go to archive.  But this makes it impossible to trash a message.  I want the delete key to archive and I want the trash button to trash.  There is a menu item to Archive, but Sys Prefs does not allow assigning a custom shortcut for the delete key with no modifier.


Why does the edit button say 'improve this question/answer' when logged out but 'edit' when logged in?

Why, when I am logged out, does the button say “improve this question” or “improve this answer”, but when I am logged in it says “edit”?   I have ~450 reputation.


I'm trying to update an account list and I need to get the Ids when the update fails.  I use the getId() method but for accounts which fail I get null.  It's an update so my account already has an Id.  Is it normal ? If it is, how can I get the Ids list of non-updated accounts ?  Here is my code :  List<Account> accountsList = [select Id from Account];  for(Account a : accountsList) {     a.Name = 'Test', }  List<Database.SaveResult> res = Database.update(accountsList, false);  for (Database.SaveResult s : res) {     if (!s.isSuccess()) {         system.debug(s.getId()); // I get null here      }  }


Animating the merging of multiple video strips

I'm trying to achieve the merging of multiple video strips like in the following . I think the clip has been animated with a vertical strip.    Could this animated area be achieved with masks in Blender?  If so, how would I go about achieving an animated visible video area, over another video?


What are these fuse-looking cartridge case components on small, battery operated RF tranceivers?

I have recently opened up 3 dead, battery-operated RF transceivers lying around, both wearable and key-chains. I've noticed that all three had components that looked like fuses (cartridge case), soldered down, that are quite large compared to the size of the circuit. See the pictures below. I'm not posting full circuit pictures because I don't know if I should, I can update if they are necessary.  Device 1:    Device 2:    Device 3:    I can't see why such a device will require a fuse, and I couldn't find any other common components manufactured in cartridge cases, maybe I'm not using the correct name. I don't see them on any applications notes or reference designs for the ICs used either.  I've tried to figure out how they are connected to the circuit, I don't have schematics and PCBs are more than 2 layers so they may not be complete, but see the schematics I've figured below.  Device 1:    Device 2:    Device 3:    Also, when I do a continuity test between the terminals of the components with a multimeter, resistance starts in ~50 Ohms range and goes down to short as I keep the probes on its terminals so my best guess is something for ESD protection, maybe Varistors or Thermistors?   Does anyone know what these components are and why they are there?


subject placeholder - It is reported that, It appears that

Is "it" a subject placeholder in the sentences below?     It is reported that one ancient Greek athlete ate dried figs to enhance training.      It appears unlikely that interest rates will fall.


Auto shutdowns on windows 10, remote attacks

Few days ago my windows 10 desktop was attacked, and changed the shutdown file/process, or modified it. Now there's a random shutdowns after 5 seconds or 30mins to 3 to 4 hours. Found a similar post, link  But there's no definite answers how to solve or fix this, Is it possible to create a counter command of shutdown -a to run in loop ? Until finding out which file or process causing this ? Any other available options to solve this ?


I often come across these kinds of problems in A-level exam papers:     Prove that    $$ \begin{vmatrix}     (a+b)^2 & 1       & 1      \\     a^2     & (1+b)^2 & a^2    \\     b^2     & b^2     & (1+a)^2  \end{vmatrix}  = 2ab(1+a+b)^3 $$   or      Prove that    $$ \begin{vmatrix}     1  & 1  & 1 \\     x  & y  & z \\     yz & xz & xy  \end{vmatrix}  = (x-y)(y-z)(z-x) $$   Questions which involve nice determinant results, but which are quite a pain to prove by expanding.   Are there any tricks that one can use to prove such results? I'm familiar with Vandermonde matrices for example, but I haven't come across anything that might help me with these, especially the first one.


Why does the conversion of mass to energy have anything to do with the speed of light?

Not looking for derivation, that is self explanatory.  But why the speed of light, not some other constant like avagadros number or number of stars or anything else?  Seems like lightspeed is special.  Can’t find this answer by google


This is what I have done so far. Although the problem in this code is that in 6th line, after 9 it prints 10,11 and so on instead of starting again at 0,1... etc.


I am planning a database which has a mini chart of accounts.  My account codes are names like:   CURRENT_DEBTORS CURRENT_CREDITORS CASH_AT_BANK   I am thinking of using the account codes as a primary key in the account database, which would mean it would be a foreign key in a transactions table.  The field would be something like CHAR(20) in MySql.  The transactions table would get about 10,000 entries per month.  How will this long-ish character index affect performance?  I can use a surrogate key if I have too, but would prefer not too.  (I'm not too worried about disk space, of course).


Can I configure an aggregate "home page" with questions from different sub stacks which meet my tags there?

I have been a Stack Overflow member for a couple of years but I'm also interested in a variety of non-computer related topics. I often check the "Hot Questions" list. But those questions, while interesting both in themselves and as an indication of what moves the community, are not custom-tailored to my interests.  Is there a way to configure a book-markable page that assembles questions from various Stack Exchange Sites which match my respective tags there, similar to my configured Stack Overflow start page but aggregated from all stacks?


Prove that $1+x+\frac{x^2}{2}+\dots+\frac{x^n}{n!}<e^x$ for all $x\in(0,\infty),n\in\mathbb{N}$

Intuitively this makes sense but I don't know how to formally show that this is true. I tried using induction but that got me nowhere .


i'm using a php script in my Android project to delete a lign from the database . here is the php file content :  <?php $pseudo = $_POST['pseudo'];  define('HOST','localhost'); define('USER','root'); define('PASS',''); define('DB','ract');  $con = mysqli_connect(HOST,USER,PASS,DB);  $sql = "DELETE from utilisateur where pseudo=$pseudo"; $res = mysqli_query($con,$sql); ?>   I think that the main problem in comparing pseudo to $pseudo


Distinguish between original and photo-shop

I have a color photo. Is it possible to find out whether it is original or made by photo-shop?


How to check file against a hash on windows 7?

How to check downloaded file against its hash (SHA-256 Hash, SHA-1 Hash, MD5 Hash) on windows?


How do I make a button take up all available space when its parent has a min height?

I have a button inside a flex box. I wanted to take up as much space as possible, but I also want this flex box to have a min height, because after you click this button it will be replaced by dynamic text. If this dynamic text is really long, I want to flex box to grow in height so that all the text fits.  Here is what I've tried:   <div class="container">     <button disabled="" tabindex="0"> Text </button> </div>  .container {     display: flex;     flex-direction: column;     margin-bottom: 3em;     width: 100%;     text-align: center;     border-style: outset;     min-height: 5em; }  .container button {     align-self: stretch; }


There are many similar questions like this. But I haven't found a usefull answer yet. So I hope some of you have a suggestion to this.  I've done some flyovers with the drone at a contruction area, and then got a DSM out of these, using Pix4D.  Now I have 2 different DSM, and then imported these into QGIS. Through rastercalculator i've withdrawn these from each other to get the height difference. See below:   I then would like to find out the volume of where there have been a height difference.. So some of the area I have marked red (increased volume) and the blue (decrease in volume). Also using rastercalculator and polygonize. See below.      Is there a smart way to find the volume of the blue and red marks of these rasterlayers in QGIS, or do any of you have an alternative program that would do the job easier and faster?


What are the options for audio equalizers in Ubuntu 15.10?

I have looked around but only found discontinued projects. What audio equalizers are able to be used in 15.10.


connect my galaxy s duos phone as mass storage or drivers

i want the drivers of my phone to be installed in Ubuntu 12.04 Lts  please help me on this


Why Standard Deviation is more popular than Mean Absolute Deviation?

$$ Mean\;Absolute\;Deviation = \frac{1}{n}\sum_{i=1}^n |x_i-mean(X)| $$ Almost all textbooks and papers are using Standard Deviation as a measurement of dispersion. And of course, almost all the models are built based on Standard Deviation.  But I don't understand how Standard Deviation has gained such popularity. I mean, Mean Absolute Deviation is a very intuitive measurement of dispersion. It tells you exact average distant that each value deviates from their mean. Standard Deviation, on the other hand, makes the result more sensitive to outliers. Why we need this sensitivity. Is there any historical reason leads us to use SD way more often than MAD?


Need help with ways to make money in Skyrim

I tried looking for similar questions to this one but was unable to find any.  I'm wondering if theres someone that knows how to make real money in Skyrim.  I don't have dawnguard or hearthfire.  My blacksmithing is around 80, maybe 82ish, and ive tried mining kolskeggr mine and selling the gold ore to pavo but that seems really slow due to the respawn rate of the mine.  Any suggestions would be greatly appreciated.  Thanks.


I want to change the name of a windows 7 machine from input from a user using a BAT file. The name i want to change is the name of the computer in advanced system settings. (see screen shot below)    The below code is what i have tried, but does not work. I have also tried running the code as administrator, and then restarting, did not work either.  SET /P PCNAME=Please enter your name:  REG ADD HKLM\SYSTEM\CurrentControlSet\Control\ComputerName\ComputerName /v ComputerName /t REG_SZ /d %PCNAME% /f


SHOULD THERE BE A QUESTION MARK OR NOT? IT'S AN INDIRECT QUESTION BUT AN ANSWER WOULD BE EXPECTED.    There's a party later if you're interested.   There's a party later if you're interested?


Incorrect icon assigned when navigating from chat

When navigating from chat, the Writers Stack Exchange seems to be assigned the World Building Stack Exchange icon. I am using Firefox 57.0 on Ubuntu.    The error was duplicatable upon revisit.


So I have this:  export ti_arg='';  if [[ -t 1 ]] ; then    # allow us to kill container if attached to terminal    export ti_arg='-ti' fi  (   cd "$(dirname "$BASH_SOURCE")"     docker build <...> '.'     docker run "$ti_arg" --rm  "test-$commit_id" )   the problem is that even if $ti_arg is empty, the shell still sees it as an argument, and I get:     docker : invalid reference format   The only solution I can think of is and if/else to run basically the same docker command except for that one arg, or to find some pass through argument that I can use with docker, like this:  export ti_arg='--noop';  if [[ -t 1 ]] ; then    # allow us to kill container if attached to terminal    export ti_arg='-ti' fi   anyone have a good solution? I guess a CLI design would always provide a --noop flag for this use case 🤣🤣...now go update all your own CLI tools 🤣


Unable to push a figure to the top of an empty page

I am writing a thesis and I have a figure which appears near the end of a chapter. It happens that there is no sufficient space for it at the last page so it is floated to the next new empty page. And it appears in the middle. I want it to appear at the top of the empty page.  I have spent a lot of time trying different combinations of the figure optional arguments "t", "!", "h" and "p". I also tried to use \phantom{\blindtext} trying to use some invisible text to push the figure up. Both approaches do not work for me. The only way is to write some visible garbage texts at the end of the figure, then it will be pushed up to the top; but of course I don't want garbage texts to appear in my thesis.  I read through some answers on similar questions but I don't want to change the margin and format of the thesis. That will make this figure inconsistent with the other figures in my thesis.  This is the last paragraph and the figure I have:  \begin{figure}[!t]         \centering         \begin{subfigure}[b]{0.48\textwidth}                 \begin{center}                \includegraphics[height=3.5cm]{pic/Pic1}                \caption{Pic1}                \label{fig:pic1}             \end{center}        \end{subfigure}%        \begin{subfigure}[b]{0.48\textwidth}             \begin{center}                \includegraphics[height=3.5cm]{pic/Pic2}                \caption{Pic2}                \label{fig:pic2}                \end{center}        \end{subfigure}        \caption{Pictures}\label{fig:pictures} \end{figure}   blah blah blah blah blah Figure~\ref{fig:pic1) blah blah blah blah Figure~\ref{fig:pic2}.


We've bought two laptops running Windows 10 Home for our employees. We need to upgrade them to Windows 10 Pro so we can set them up with BitLocker.  How can I easily buy two license keys for these computers?  I'm aware that it's possible to purchase an upgrade on the computers directly using the Microsoft Store (as detailed in the question: ), but I'd like to purchase product keys in bulk.


I try to install make on Ubuntu 12.04 LTS Server  apt-get install make   But I observe error:  Temporary failure resolving 'de.archive.ubuntu.com   Failed to fetch http://de.archive.ubuntu.com/ubuntu/pool/main/m/make-dfsg/make_3.81-8.1ubuntu1.1_i386.deb   Could you describe me what happened?


How do I list all package names in a specific category using Terminal?

How do I list all package names in one section? If, for example, I want to list all applications in section "web", which command do I need to input?


What is the mysterious stranger doing in my vault?

This morning after the new Fallout Shelter update (1.2), I saw a mysterious stranger hiding in one of my rooms. When he is tapped  there is a sound cue and he disappears in a puff of black vapor.   Does anyone know what's going on here?


How to make an iso image of linux machine

Ok so basically I wipe my machine a lot. And I take about an hour to reinstall Linux and reinstall/uninstall all my programs. It would be nice to just load Linux with all my preferences already there. Is there a way to do this? I’ve tried DD and it seems to use my ENTIRE hard drive (even empty parts of the drive).


Why negative and positive degree of cosine function is the same?

I calculated $\cos(30^{\circ})$ and it is $\frac{\sqrt(3)}{2}$. I calculated $\cos(-30^{\circ})$ and it is $\frac{\sqrt(3)}{2}$. And, I don't know why? Can you explain me simply? I think that figures will be very much helpful.


What's the workflow to bulk delete e-mails from within Gmail?

I'm getting the out-of-storage space error for Gmail:    Since I'm , what's the correct way to delete all e-mails within a label without creating a filter or deleting the label itself?


I am currently staying in eastern/northern Iceland and am trying to spot the northern lights. Do you have any tips to see them and/or can tell me how likely it is to spot them in the next week?  The  shows aurora activity around 2 (moderate) on a scale from 0 to 9.


dimension of a symmetric matrix with trace zero

what will be the dimension of symmetric matrix of order $n\times n(n\geq2)$ with real entries and trace is equal to zero?  The answer is given as :$\frac{n^{2}+n}{2}-1$  can anyone explain how will get this answer?  according to me is should be:$\frac{n^{2}-n}{2}-1$


Google is counting the domain home page ("/") as a duplicate of "/index.html"

For only my index pages, I am receiving this warning in Google Search Console:     Duplicate, submitted URL not selected as canonical   I know that this occurs because Google is attempting to track both the default landing "page" (i.e. www.domain.example/) and the page to which to which DirectoryIndex points (i.e. www.domain.example/index.html). They are, in fact, the same page, and so the warning is the result of a false positive.  Two questions for our community:   Why does Google not conflate these and count them as a single page? Alternately, is there something wrong with my set up if this has happened? I can easily force both pages to point to a single canonical URL. But which is preferable, "/" or "index.html"?


java.lang.NullPointerException: Cannot print array contents

I am trying to write a simple Banking program.  The basic functions are :   1. open account - (open <amount>)-- returns account number 2.check balance - (balance <AccountNumber>)   The code for following is this.I am not posting my other classes and the class which contatins   main(), because I believe the problem lies somewhere in this code ::  public class BankAccount { private static int bankAccNoGen=1001; private int balance; private int bankAccNo; private  int i=0;  BankAccount[] bankArray=new BankAccount[10];  public void openBankAccount(int openAmount){     BankAccount ba =new BankAccount();     ba.balance=openAmount;     ba.bankAccNo=bankAccNoGen;      bankArray[i] = ba;     System.out.println("Account opened with the account number : "+bankArray[i].bankAccNo);     System.out.println("Please note the account number for later use.");     System.out.println("Balance for account no : "+bankArray[i].bankAccNo+" is : "+ bankArray[i].balance);     ++bankAccNoGen;++i;  } public void printBalance(int accNo){       for(int i=0;i<10;i++){         if(bankArray[i].bankAccNo==accNo){             System.out.println("Account Number :"+ accNo +" currently has :"+bankArray[i].balance);         }     }  }   }  After running this I can open a bank account by :  open 1000   output:  Account opened with the account number : 1001 Please note the account number for later use. Balance for account no : 1001 is : 1000  I can check balance by :  balance 1001   Error:    Exception in thread "main" java.lang.NullPointerException  at  BankAccount.printBalance(BankAccount.java:27)  at  ReadInput.inputRead(ReadInput.java:36)     at  SimpleBank.main(SimpleBank.java:11)


Bootloader Problems Grub Won't Load Windows 7

I sent this to boot.repair@gmail.com, still no response thought I could get a faster solution here.  I am running Windows 7 64-bit and Ubuntu 12.04 LTS on separate partitions.  The message is sent is:  Boot-Repair URL:    Originally I was unable to access Ubuntu after a windows update (Ubuntu was installed using wubi). Rather than logging into Ubuntu from the Windows 7 Bootloader, it lead to the grub> command prompt.  No matter what I did here, it would not log me into linux.  As a result I uninstalled Ubuntu from the Add/Remove Programs application in Windows 7.  I then re-installed Ubuntu 12.04 LTS using a liveCD-USB.  This time however, I created a partition.  I then restarted and got the GRUB bootloader which loads Ubuntu 12.04 LTS with no problems, however when I select windows (listed as "Windows 7 (loader)"), it just refreshes the grub bootloader instead of loading Windows 7.  I then used the Windows 7 repair disk to run bootrec/fixmbr and bootrec/fixboot.  This led to no bootloader coming up when I started my computer.  Instead I got a blank black screen with a flashing white cursor.  I went on to do a bootrec/buildbcd and bootrec/scanos.  These did nothing to change the situation.  When I ran bootrec/scanos it said that no Windows 7 installations were present.  After this I decided to reinstall WIndows 7 only for this to do nothing to change the situation.  Afterwards I did a boot-repair in which I began to get the GRUB bootloader, which would load ubuntu 12.04 LTS, but still would not load Windows 7.  I also did a sudo update-grub which recognized Windows 7 as being installed, but still didn't fix the issue of loading Windows 7.  While running Ubuntu I have no problem accessing my WIndows 7 partition which is formatted as NTFS.  It shows all the files and folders reflecting that the re-install did take place, and it also shows all of my old applications and folders in the Windows.old folder.  I am completely stuck at this point and have no clue what I should do next.  Any help you can offer me will be greatly appreciate.  Thank You  --gap


How do I get Bumblebee working on Ubuntu 14.04?

I have an Alienware 14 that I plan to dual boot Windows 8.1 and Ubuntu 14.04 on. I'm wondering what the best procedure to get Bumblebee working is.  Would I be okay to install bumblebee (if someone could give me the exact package names I need to install I'd appreciate it) and then go get the latest NVIDIA drivers from NVIDIA's website? The "Additional Drivers" section only has version 331 which is outdated.  From what I understand, NVIDIA has their own solution but it drains battery life. Ideally, I'd like to be able to just select which GPU I want to use to run a program just like in Windows.


Estimating Spline curve by OLS. Is a good idea to fix the knots at Chebyshev sites?

I am writing my master's degree thesis on a novel method for fixing knots in an adaptive way and while reading the literature I've found many references to the so-called Chebyshev sites. This sites or points are basically the roots of the Chebyshev polynomials, and there's a proof showing that the Lebesgue constant (a measure that allows us to see how good is a polynomial interpolation) is very close to its lower bound if we put our knots in those sites. A practical guide to splines (De Boor, 1972) for example provides such a proof.  Anyway I am not interested in polynomial interpolation with splines, but in regression using LASSO on a set of B-splines . On Numerical methods in economics (Judd, 1998) it's stated that the results regarding the 'optimality' of the Chebyshev sites hold also for the regression case, but there is no proof showing that the latter is true.  I would like to know if it's a good idea to estimate the regression using B-splines constructed over a knot sequence given by the Chebyshev sites, since in the OLS framework I am not interested on minimising the Lebesgue constant but rather I want to minimise the $\| \cdot \|_2^2$. In many articles I've found phrases like "we will set the knots at the Chebyshev sites, that are well known to be good..." making allusion to the results presented in De Boor, but ignoring that those refer to the interpolation case.  If your could put some light on the problem I will be very grateful.


What does the ~ symbol mean next to the files that are listed with ls?

I created a file named xxx on my Desktop and then I (re)moved it using terminal. Now when I execute ls on Desktop I see a file named xxx~ that is not visible at GUI. What does it mean?


How to check if field of type reference revisions is paragraph or others?

I am creating paragraph field programmatically dynamically from array.   The logic for creating a paragraph field is different from others entity revisions.  Is there a way we can identify if field of entity type revisions is paragraph and not others?


How do I delete all music from an iPhone 5? It got loaded from my computer without me checking the box. I tried to follow the directions from one search result with no success.


Using Fermats prime numbers to prove that there is infinitely many prime numbers

A Fermat number $F_n$ is of the form $F_n = 2^{2^n} + 1$  Furthermore, $F_n = 2 + F_0F_1F_2......F_{n-1}$ Now I already proved that  if $n \neq m$ then $\gcd(F_n,F_m) = 1$  Here is the proof  Without loss of generality , I assume that $m > n$ then we know that $$F_m = 2 + F_0F_1F_2........F_nF_{n+1}.....F_{m-1}$$ I assumed here that $n > 2 $ and $n < m-1$  Now we assume that $\gcd(F_n,F_m) = d$ then $d \mid F_n$ and $d \mid F_m$  Now if $d \mid F_n$ then $d \mid F_0F_1.....F_nF_{n+1}...F_{m-1}$ and so $d$ divides any linear combination of $F_m$ and  $F_0F_1.....F_nF_{n+1}...F_{m-1}$, In particular $d \mid Fm- F_0F_1.....F_nF_{n+1}...F_{m-1}=2$ and hence $$d \mid 2$$  Now since all Fermat numbers are odd then $d \neq 2$ and hence $d=1$  Now I want to use this to prove that there exists infinitely many primes.  I know that since Fermat numbers form an infinite sequence of increasing numbers and each Fermat number is relatively prime to all other Fermat numbers then we have infinitely distinct prime divisors for each composite Fermat numbers and we also add to those Fermat prime numbers.  I feel like there is a better mathematical argument that that novel that I wrote above :)


So I got a problem here. So I installed SDL 2.0.1, everything worked fine, I installed dependencies of sdl as well, so I saw that it didn't worked, so I rebooted my pc, after that I get to gnome, and don't know what do, maybe some help? :)


Prove, that if the commutative ring has no zero divisors, then it is a field

Let $R$ be a commutative finite ring in which $ab = 0$ implies either $a = 0$ or $b = 0$ for any $a,b \in R$. Then, $R$ is a field.   I do not understand how I should act. I tried different ways, but I was not able to prove this assertion.


I'm running on a couple of different Linux distros (Fedora 11, CentOS 5 and SuSE 10.2) and  often run into a problem where a new script that I want to run as a cron job works fine when called direct from the command line, but fails when called from cron due to slight variations in the PATH or other required environment variables.  Is there a way I can test run an individual script as if it's being run from cron, without having to run the entire crontab or use run-parts to run the entire cron.daily/ .hourly etc. directory ?  I guess I could temporarily edit my crontab to run the script in the next couple of minutes, but I'd rather have a more standalone solution so that I don't risk messing up the crontab.


How to Select "Inverse" of intersection of two polygon layers?

I'm wondering if there's a way to intersect two polygon layers, take the intersection, and remove that from one of the polygon layers, making a new layer out of whatever is left over? Basically, the idea I have is one of "punching holes" in a map of Africa where the holes are points around which I construct some sort of buffer. I have QGIS and ArcGIS 10.0. Is there a built-in or user created script for this?


How to keep cell blank until date entered

So basically, "INVOICE DUE DATE" is the SUM of D11+7 ("Date invoice sent out" + 7 days as this is when the invoice is due). However, when there is no date inputted in "DATE INVOICE SENT OUT" the "INVOICE DUE DATE" cell shows 07/01/1900. I want it to show blank until I input a date into D11.   Also - the "DAYS REMAINING" column (K11) is made up of E11-B2 (invoice due date - =TODAY(). I again want this to show as blank until the SUM is complete.  Finally - 2day, 4day and 6day chase are made up of D11+2,D11+4 and D11+6. I want these to show as blank until D11 date entered.


I'm having trouble understanding how a  (not the  that is generated as a result but the material itself) work. The particles are aligned in a specific direction to give rise to force but I don't see how this alignment gives rise to "attraction" or force.


What is the best way to declare "string" variables in C #?

I'm a new developer and I have two questions, I researched and it wasn't very clear to me.  What is the difference between using a "string" variable to "String"?  what is the difference between the two examples below  string my_example = "title (..)";  to   const string my_example = "title (..)";


So I just created the .bash_aliases and wrote the following:  callNotepad(){      wine C:\\Program\ Files\\Notepad++\\notepad++.exe $1 }  alias notepad++=callNotepad   Now whether notepad++ is already running or not, if it is not it does open notepad++ and either way, it opens whatever file I specify when I call  notepad++ someFile   However, if notepad++ was not running prior to that command, it gives me a      fixme:ole:RemUnknown_QueryInterface No interface for iid   {00000019-0000-0000-c000-000000000046}   and then blocks the calling terminal for as long as notepad is running.  How would I implement that alias correctly? For I have no idea what that fixme is supposed to tell me.  Also, I would prefer not having to open a second terminal after opening a file in notepad++ (ctrl+C reenables the terminal but closes notepad++).


What are the equivalencies between the higher education in France (Licence - Master - Doctorat) and the higher education in the United States?

In France the higher education is like this:   3 years of "Licence" 2 years of "Master" 3 years of "Doctorat"   But what about in the United States?  I heard that they have things called "undergraduate", "graduate" and "postgraduate". How many years do each of those take? And what are the equivalencies between these and the "Licence - Master - Doctorat"?  Note: If the answer to this question depends on the field of studies, then the field is physics.


I have a custom content type in Drupal 8.6.x. I want to be able to change the text used for a field label based on the value of a taxonomy term reference in the node.   For example, I want to change the field label used for the body field, to display "Description" or "Definition" or "Introduction", etc. based on the value in the taxonomy reference field. This is when rendering the node - I don't need to change the field label on the form. I'll need to alter the label in the full and teaser display modes, and just for the custom content type. I don't need to change any of the text in the body field, just what label is shown above it.