Showing that $x \mapsto |x|^p$ is strictly mid-point convex for $2 \leq p < \infty$

Let $2 \leq p < \infty$ and consider the function $f : \mathbb{R}^n \to \mathbb{R}$ defined by $$f(x) := |x|^p.$$ Then this function is mid-point convex (in fact strictly), i.e. we have that $$f\left(\frac{x + y}{2}\right) \leq \frac{f(x) + f(y)}{2}$$ holds for all $x,y \in \mathbb{R}^n$. Is there a nice way of showing this?


Please have a look at this sentence:     We haven't gotten a lot of Finnish groups that we liked here at Bananas but I'm pretty happy with this four tracker from Helsinki, apparently recorded in the same place where the Ramones played in the 70's.     The first verb is in present perfect (up to now) and the second is in simple past tense. I don't understand the simple past for the second verb.  Why "like" is not in its present perfect form as the first verb is?


A bioinformatics department at a University has 100 professors- some are honest and hardworking, while others are deceitful & do not like students. The honest prof. always tell the truth, while the deceitful ones sometimes tell the truth and at other times lie. You can ask any professor Y the following question: “Professor Y, is Prof. X honest?” Y will answer either “Yes” or “No”. Design an algorithm which will help you figure out which Profs are honest and which lie. What is the minimum number of questions you need for this purpose? [It is known that there are more honest Prof. than deceitful Profs]  Question is taken from a book. I really can't solve this problem. Can somebody help?


Is it imperative , interrogative or what ?  A question I got online asks, " What is the simple subject of the following sentences ? is the sentence imperative or interrogative ?   question 17 : Will you check the tires.  using a( full stop) not a question mark.  First, is it correct or wrong to start with ( will) and ending the sentence with a full stop ?  OR perhaps it is mistyping, but it is not the only question   It is already a request ( polite command ) but how it doesn't end in a question mark ?


Is it possible to reverse perspective projection with simple scale and translate?

Basically I'm asking this question (which seems to have gone un-answered):   I'm using perspective projection and would like to scale up certain objects in the background (z < 0) such that they would render unscaled and in the same relative position. In other words, I want to reverse the perspective foreshortening for bg objects.  I've figured out how to unscale accurately: basically I project the top left and bottom right corners of the image to z = 0, then do the same at the current z value. I then compare the change in distance between the points in order to derive the scale factor.  The problem I have though is once I unscale the object, its position is incorrect. I've tried scaling around different anchor points, with no luck. I can't seem to derive a generic formula to position the images in the correct places after scaling.  Any ideas how to do this? Is this even mathematically possible?


I wanted to move  1000 files in a directory to another dir.  I can do it if I'm in the original dir but if I try this   mv $(ls /home/jeremy/source|tail -1000) /home/jeremy/dest   from elsewhere, the path gets stripped and so I would need to append the path somehow. I find the $ convenient and wanted to avoid xargs as it seems tricky.


Resolving Java script Alert that This page was unable to display Google Maps element?

Whenever I try to load the Google Hybrid layer on QGIS 1.8.0 and 2.0.1, I get this error:     This page was unable to display a Google Maps element. Please contact the site administrator. If you are the administrator of this site, please check the JavaScript console or check the following page for troubleshooting:    How do I correct the error so that the map can load?


Command to find the folders modified on a particular date

I need to find the folders that are modified on a particular date, month and year  i was able to find the files modified based on date and month. I also want to include the search based on year ls -ltr | awk '$6 == "Aug" && $7 >=01 && $7 <= 31 &&  {print $9}'


A class from a subpackage needs to access a class from a package one level up. So, I need to keep the target class as public. But I don't want that class to be accessed by any other class. What can I do?


Show that $S$ is subset of f$^{-1}(f(S))$

Here is the full question:  Let $f : X → Y$ be a function from one set $X$ to another set $Y$ , let $S$ be a subset of $X$, and let $U$ be a subset of $Y$. Show that $S \subset f^{-1}(f(S))$  My main problem is that I am not able to translate my reasoning to a formal Mathematical proof, here is what I am thinking of: Every element $x \in S$ has a forward image $f(x)$ , $f^{-1}(f(S))$  will either return the same set $S$ (in case the function is one-to-one) or will return a set with more elements than $S$ (function isn't one-to-one, multiple inputs mapping to one output) where all elements of $S$ are in this set along with another new elements, either way all elements of $S$ will be in $f^{-1}(f(S))$ which is the definition of a subset. What I tried: I tried going back to the original definitions of a forward and inverse image in a way that I start with an element $x\in S$ and prove it's in $f^{-1}(f(S))$ but I can't see it using the formal definitions.


Show that   $\log_7 n$ is either an integer or an irrational number where n is a positive number.   I assumed that it is rational and tried to get a contradiction for $\log_7 n = a/b$, where b does not divide a, but how can I show that $7^{a/b}$ is not an integer to achieve a contradiction since n is an integer ? If I can exclude rational numbers from the range of log function then it is either integer or irrational.  Or do you suggest other methods ?


I don't know what to do to unfreeze my question, ask again?


Excel grey and black boxes on secondary display

My secondary screen doesn't display Excel properly: it has gray, black and white boxes and lines everywhere. As I scroll up and down, or zoom in and out, the boxes disappear and and then reappear in different places. I have tried upgrading from Excel 2013 to Excel 2016, but the issue is the same.    (Click image to enlarge)  Laptop: Dell XPS 13, Intel HD 520 Monitor: Dell U27"


I encountered a problem using equals, let me first add the code here :  Operateur o = new Operateur(nom, age, sexe, grade, role); for(Operateur op : Membre.getOperateurs()){   if(o.equals((Object)op)){     already_exists = true;     break;   } }  if(already_exists){   ret = ">Can't create it : already exists";   Membre.removeLast();   o.finalize(); }else{   ret = ">Created it"; }   Here I check if a new Operateur isn't just a copy of an old one (Membre.getOperateurs gets me the list of all instances of Membre that are actual Operateur).      My problem is that when I run this bit of code, if my Operateur is brand new it appears as already existing (which he should not, since he's brand new).  For instance, when I create the first Operateur ever it evaluates it as a duplicate of an already existing one.  As :  import cmd.*; import matrice.*; import persona.*; import non_grata.non.*; import non_grata.grata.*; //all above is importing packages to use all classes required   public class Debug{   public static void out(String s){     System.out.println(s);   }//handy    public static void main(String[] args){     Membre.init();//Membre.membre = new ArrayList<Membre>();     Personnel.init();//Personnel.membre = new ArrayList<Membre>();     Vaisseau.init();//Vaisseau.vaisseaux = new ArrayList<Vaisseau>();     MatrixCmd cmd = new MatrixCmd();//Create the command parser      String parser_input = "afficherMembres";//get some input     String parser_output = cmd.execCommand(parser_input);//process it     out(parser_output);//use it     //empty list, correct since we only initialized it      parser_input = "newOPsion mikebike 10 o string string";     parser_output = cmd.execCommand(parser_input);     out(parser_output);     //outputs ">Impossible de créer cet Opérateur : Il existe déjà" which it shouldn't     //since there are no other Operateur and this is only     //given as output when it founds a similar Operateur      parser_input = "afficherMembres";     parser_output = cmd.execCommand(parser_input);     out(parser_output);     //outputs an empty list, meaning that there are no Membre created     //and therefore no Operateur      parser_input = "newOPsion mikebke 8 f tring sring";//command that will trigger the bit of code above     parser_output = cmd.execCommand(parser_input);     out(parser_output);     //outputs">Impossible de créer cet Opérateur : Il existe déjà" which it shouldn't   } }


"There is any number of" vs "There are any number of"

There is any number of ... There are any number of ...  Intuitively I'd say 'are', but 'number' is singular, right? Please note that this question is different from these two questions here:     This is because verb agreement is not nearly so straightforward in existential constructions. We see many phenomena that occur in existential constructions that don't occur in normal sentences. This question is asking about this choice within an existential construction. Also, would it be more appropriate to put " in the title of this question, or ' ?


Change page title from Views preprocess function

I want to be able to change the main page title based on some value that I get in a views preprocess function.  The View is displayed as a page.  function MYTHEME_preprocess_views_view(&$variables) {    // Can I set the page title from here? }   The title I am trying to override is the title printed by the /templates/content/page-title.html.twig below:  {# /**  * @file  * Theme override for page titles.  *  * Available variables:  * - title_attributes: HTML attributes for the page title element.  * - title_prefix: Additional output populated by modules, intended to be  *   displayed in front of the main title tag that appears in the template.  * - title: The page title, for use in the actual content.  * - title_suffix: Additional output populated by modules, intended to be  *   displayed after the main title tag that appears in the template.  */ #} {{ title_prefix }} {% if title %}   <h1{{ title_attributes }}>{{ title }}</h1> {% endif %} {{ title_suffix }}


Permanent redirect all http requests to include www subdomain

I have noticed both google.com and amazon.com, redirect requests to www.google.com and www.amazon.com  I am thinking of doing the same for my website which is hosted on AWS. What is the best approach to do this? I am not sure if it would be better to implement this in Load Balancer or S3? Also is there any downside to always redirecting to www sub-domain?


Is there a way to specify fragile mode as default for all frames? Now I know how to define a fragile frame: \begin{frame}[fragile].


Why do I not get a p-value and F value from ANOVA in R?

I am asked to determine using an appropriate test whether the internal concentration of isoleucine is statistically different between appropriate experiments. So I constructed a data frame in R as follow: dat <- data.frame(experiment = c('no glu', 'glu', 'gluFCCP', 'gluV', 'gluN', 'gluNV'),internal_concentration = c(2.38, 8.57, 3.42, 6.17, 4.58,3.51))  print(dat) experiment     internal_concentration 1     no glu                   2.38 2        glu                   8.57 3    gluFCCP                   3.42 4       gluV                   6.17 5       gluN                   4.58 6      gluNV                   3.51  I chose to perform an ANOVA test: model<-lm(dat$internal_concentration~dat$experiment)  anova(model)  Analysis of Variance Table  Response: dat$internal_concentration                Df Sum Sq Mean Sq F value Pr(>F) dat$experiment  5 25.558  5.1117                Residuals       0  0.000    I need the F and p values to determine if there's a significant difference, but this result is not working. How should I interpret this error and any suggestion on how to change the code/method?


Proxy for Mahalanobis distance when n < p?

I'm working on a ranking problem where I want to measure the distance between a collection of query points (as a group) and each target point in my database. Each query point is part of the set of target points. I started with the Euclidean distance and cosine similarity by using the mean vector of the query points. However, the results were not satisfactory possibly because both of these measures don't take into account the variance and covariance of the query points. I stumbled across the  which seems to be exactly what I want to try: Measuring how many standard deviations a point is away from the mean of the subsample.  The problem is that I work in a 256-dimensional space while the number of query points is usually much lower than that. Therefore, I cannot calculate the Mahalanobis distance which relies on the covariance matrix. In order to calculate it, I need more observations n than dimensions p.  1) Is this assumption correct?  The past days I've been thinking about how I could still do "better" than the Euclidean distance without having enough data to calculate the Mahalanobis distance.  I thought about switching out the covariance matrix for the diagonal matrix of variances. As long as none of the variances is zero an inverse can be calculated.   2) Does this idea have a flaw?  Since the 256-dimensional vectors are the result of PCA over all target points, I could use n points to create a covariance matrix over the first n-1 dimensions and then fill the rest of the needed 256-dim covariance matrix with the diagonal of variances from before.  3) Would that make any sense?  4) Any other ideas that might help me to measure a more meaningful distance between a point and a subsample of points?  Please note: A very similar question has been asked  but I believe my problem is still different. There, OP wanted to measure pairwise distances between points given all points. I want to measure the distance between the distribution of a subsample to all other points. I believe, the reasoning of the accepted answer does not apply to my problem since the distribution of the subsample is likely to be different.


Are units of angle really dimensionless?

I know mathematically the answer to this question is yes, and it's very obvious to see that the dimensions of a ratio cancel out, leaving behind a mathematically dimensionless quantity. However, I've been writing a  (the specifics of which are out of scope), which has me thinking about the problem because I decided to handle angle units as dimensioned quantities, which seemed natural to enable the unit conversion with degrees. The overall purpose of the library is to disallow operations that don't make sense because they violate the rules of dimensional analysis, e.g. adding a length quantity to an area quantity, and thus provide some built-in sanity checking to the computation. Treating radians as units made sense because of some of the properties that dimensioned quantities seemed to me to have:  The sum and difference of two quantities with the same dimension have the same physical meaning as both quantities separately. Quantities with the same dimension are meaningfully comparable to each other, and not meaningfully comparable (directly) to quantities with different dimensions. Dimensions may have different units that are scalar multiple (sometimes with a datum shift).  If the angle is treated as a dimension, my 3 made up properties are satisfied, and everything "makes sense" to me. I can't help thinking that the fact that radians are a ratio of lengths (SI defines them as m/m) is actually critically important, even though the length is cancelled out. For example, though radians and steradians are both dimensionless, it would be a logical error to take their sum. I also can't see how a ratio of something like (kg/kg) could be described as an "angle". This seems to imply to me that not all dimensionless units are compatible, which seems analogous to how units with different dimensions are not compatible. And if not all dimensionless units are compatible, then the dimensionless "dimension" would violate made-up property #1 and cause me a lot of confusion. However, treating radians as having dimension also has a lot of issues, because now your trig functions have to be written in terms of $\cos(\text{angleUnit}) = \text{dimensionless unit}$ even though they are analytic functions (although I'm not convinced that's bad). Small-angle assumptions in this scheme would be defined as performing implicit unit conversions, which is logical given our trig function definitions but incompatible with how many functions are defined, especially since many authors neglect to mention they are making those assumptions. So I guess my question is: are all dimensionless quantities, but specifically angle quantities, really compatible with all other dimensionless quantities? And if not, don't they actually have dimension or at least the properties of dimension?


What happens when we type a simple command on shell?

I have a simple question regarding the execution of a simple command. As per my understanding, when we type a command such as ls in an interactive shell,    Shell interprets the command. Shell creates a child process and executes the command on the child process. Shell waits for the child process's completion.   If my understanding is correct, a simple command we typed on shell prompt is executed on a child process and the command's result does not affect current shell's environment.  If so, what about built-in commands like cd? If cd is executed on a child process and can not affect current shell's environment, how can the current shell's working directory can be changed?


How would embedded quotations be used when quoting from passages/sources within an essay? What would be the difference between normal quotations and embedded quotations?


In Java 8, is it possible to use JVM parameter to control when(or in what condition) to unload class?

In my JMeter test I find that JMeter keep loading classes javascript_gen_cmd__xxx and it makes the test can't reach the throughput I set.   When I click "Perform GC" button in JVisualVM, the classes are unloaded and the throughput is reached.  So i think it would help if I could indicate when the GC should happen, for example when the total number of loaded class reach certain number.  I tried -XX:MetaspaceSize=120M but it didn't trigger class unload when the metaspace usage reached 120MB.


Start new line automatically when otherwise content would overflow cell

I don't know when Google changed the version of Spreadsheets. Right now when the cell's text is longer than the cell width the display of this line is no longer what it used to be. I want the display of the text to be broken into lines when it is too long, as before.  I've made two examples :    Cell 1: Since there is no content in the cells adjacent to the right, content is displayed over the cells beside it, which makes the cell look like a super long combined cell.    Cell 2: Since there is content in the cell beside it, much of the content is hidden automatically. People cannot see the content unless the cell is clicked.  How can I make such text automatically break into enough lines that all is visible?


Book series with a shape shifting dragon girl

Does anyone know the name of the book series about a girl who finds out she can turn into a dragon and has to learn how to? She falls in love with a human guy who is fine with her being a dragon and she ends up having to fly to an island where other dragon people are to find them and save their race...


How to attack a "many-time pad" based on what happens when an ASCII space is XORed with a letter?

I've already sent my correct solution to :  "Let us see what goes wrong when a stream cipher key is used more than once. Below are eleven hex-encoded ciphertexts that are the result of encrypting eleven plaintexts with a stream cipher, all with the same stream cipher key. Your goal is to decrypt the last ciphertext, and submit the secret message within it as solution. Hint: XOR the ciphertexts together, and consider what happens when a space is XORed with a character in [a-zA-Z]."  I managed to get the key by XORing ciphertexts #1 and #2, then XORing the result with the string " the " at each possible position.  Combined with a lot of guesswork, this gave me the first plaintext. My question is: What would I have to do if I want to follow the hint? I know that if I XOR a space with a letter, I change the case of the letter, but then what? I don't understand how I can recognize spaces!  Suppose I see a letter in $c_1 \oplus c_2$; how can I tell if there was a space in one of the plaintexts?


Coding in Java, Issues with Initializing Deck of Cards

I am writing code that is supposed to initialize a deck of cards, shuffle them, and then deal them to a specific number of players. I have written all the necessary methods, however when I try and implement them it compiles but when I run it I get a NullPointerException that's originating from my shuffle method.   What I'm thinking is that something is going wrong in my initialization of the deck of cards and thus when I try and access the deck in subsequent methods I'm getting the exception.  I'm just not sure what's going wrong and would be very grateful for some help! Here is the code:  (The exception appears when I attempt to switch the cards in the Shuffle method)  import java.util.Random; import java.util.Arrays;  public class Deck {      private Card [] arrCards;     public Deck()    {      Card [] arrCards = new Card[52];       String [] suits = {"Hearts", "Spades", "Diamonds", "Clubs"};       int count = 0;       for(int i = 0; i < suits.length; i++)      {        for(int j = 1; j <= 13; j++)        {           Card deckCards = new Card(suits[i], j);           deckCards.print();           arrCards[count] = deckCards;           count++;         }        }      }    public void shuffle()   {     int seed = 123;     //create arbitrary new temp card     Card temp = new Card("Hearts", 1);     Random randNum = new Random(seed);      for(int i = 0; i < 1000; i++)    {       int firstRand = randNum.nextInt(52);       int secondRand = randNum.nextInt(52);        temp = arrCards[firstRand];      arrCards[firstRand] = arrCards[secondRand];      arrCards[secondRand] = temp;     }    }   public Card [] dealHand(int n, int playerNum)  {      Card [] playerCards = new Card[n];       int counter = 0;      int start = (n  * (playerNum - 1));      int end = start + 12;      for(int i = 0; i < n; i++)     {       for(int j = start; j < end; j++)       {        playerCards[i] = arrCards[j];         }       }     return playerCards;  }   }  Thank you so much I really appreciate it! (Especially since this is probably a really basic mistake somewhere)  :)


How fast can the Galaxy class Starships go in reverse?

I've seen them maneuver. They definitely can go backwards. How fast can they go in reverse? Is warp speed possible, or is reverse limited to impulse power? If it is limited to impulse power, can they travel backwards under impulse power as fast as they travel forwards under impulse power?


Find values of $a$ for which function will have real roots

Find the range of values of $a$ for which the equation $$2x^3-3x^2-12x+a=0$$ will have all roots real and distinct.   what i tried  I found the derivative and got the roots of $f'(x)$ as $-1,2$ but now i need another condition to find values of a but i don't know what that condition should be.  Thanks in advance !


Supervisor process exits with 'exit status 1; not expected'

I'm trying to run a gunicorn_django process in supervisor but it always exits immediately, giving this error:   INFO exited: my_app (exit status 1; not expected) INFO received SIGCLD indicating a child quit INFO gave up: my_app entered FATAL state, too many start retries too quickly   My server script looks like this:  #!/bin/bash set -e LOGFILE=/var/log/gunicorn/my_app.log LOGDIR=$(dirname $LOGFILE) NUM_WORKERS=3 USER=my-www-user GROUP=my-www-user cd /home/my-www-user/my_app source /home/my-www-user/.virtualenvs/my_app/bin/activate test -d $LOGDIR || mkdir -p $LOGDIR gunicorn_django -w $NUM_WORKERS --debug \  --user=$USER --group=$GROUP \  --log-level=debug --log-file=$LOGFILE 2>>$LOGFILE\  --pythonpath=my_app --settings=settings.active \  my_app.wsgi:application   And my supervisor config looks like this:  [program:my_app] directory=/home/my-www-user/my_app/ user=my-www-user command=/home/my-www-user/my_app/server.sh stdout_logfile=/var/log/supervisor/my_app.log stderr_logfile=/var/log/supervisor/my_app-error.log autostart=true autorestart=true   When I su into the my-www-user account the server starts normally. When I do sudo supervisorctl start my_app it simply hangs until I do CTRL-c, then I find the error above in the supervisord.log file.  Does anyone have a clue about what I am missing?


"along the river" vs "alongside the river"?

In a question on "along" vs "alongside", I have seen this question and the correct answer on the web site makes me confused.      The question is: I enjoyed my walk _________________ the river.  a) along b) alongside  I selected "...along the river" as the correct answer, but on the web site it is shown as wrong and the correct answer is "alongside".  How can that be? I still do not agree, because I have studied the difference between the two. "along" is just the right preposition for thin and long places like road, path, street, beach etc".   So, why would the correct answer be "alongside" which simply means "next to"? Do you not think "along" seems to be better fitting?  Regards,  Note: I would be more than gratefull, if somebody show it to me in a video, like "a walk along the river" and "a walk alongside the river". Maybe I can understand the how "a walk along the river" and "a walk alongside the river" would take place.


Equality of determinants $\det(1+AB)=\det(1+BA)$

Can someone help me out with this identity?  We are given two matrices $A$ and $B$. The matrix $A$ is $m\times n$ while $B$ is $n\times m$ matrix. We need to prove that     $\det(I+AB) = \det(I + BA)$ where $I$ is the corresponding identity matrix.   Please use elementary steps to solve as I don't have enough knowledge of matrices.  I checked out the Sylvester's determinant identity page in maths stack exchange. The proofs were out of my scope. Can it be done in an easier way?


Toggle Switch to swap the connections of two buttons

I am trying to mod my arcade stick so I can switch two commonly swapped buttons on the controller.  Essentially they are simple 2 terminal momentary switches connected directly to the controller PCB. I would like to switch their responsibilities, so in my case the Back button and the LB button on the XBox pcb I would like to swap so the Back actuates the LB button on the PCB and the LB actuates the Back button.  My assumption is that I would need a switch with 8 terminals, 4 in 4 out.  What type of switch am I looking for?


Nvidia Optimus not connected to any display?

While trying to spec out a Lenovo T440p ThinkPad with Nvidia graphics and a docking station allowing for dual monitors, I found a  implying that the Nvidia Optimus could not be used with docking station outputs.  This claim was made from display topology information found in a :     Since Optimus Technology has the ability to use two display adapters, some    display monitors (or displays) are assigned to specific adapter. Below    describes which display adapter controls the display connector for a certain    display monitor.      Thinkpad T440, T440s, T440p, T540p   Intel HD Graphics      - (Computer's LCD)      - Computer's analog VGA connector      - Computer's DisplayPort connector      - Docking Station's analog VGA connector      - Docking Station's DVI connector(s)       - Docking Station's DisplayPort connector(s)      - Docking Station's HDMI connector  NVIDIA GeForce GT 730M, GeForce GT 720M      - No display is connected to this display adapter.    What good is the Nvidia adapter if it isn't connected to any display?  I assume there is more to the story here, but I am not familiar with how these two graphics adapters interact with each other.  Is there any way to use the Nvidia adapter with docking station ports?  And if not, how does the Nvidia adapter work at all?  The text file goes on to talk about "standard mode" and "advanced mode".  The "advanced mode" seems to allow more display pin configurations, but isn't available on the T440p.  There is also a note about cross-adapter display cloning, but I do not believe this applies to my situation.


AMD RX480 Screen flicker after update to 18.04

As mentioned in the title. Was upgrading from 17.10. Having this screen flickering.  My GPU is AMD RX480  What I did:   Search for similar issues for 18.04, can't find any Perform fresh install. Still the same.   Please help. It is very annoying. I can't work.


I can use many of the site's features while unregistered. I am looking for a simple explanation of what benefits a user can have from registering.     For more information, see  in the .


Force sum of random varables to equal to 1

Suppose I have 3 random variables, $X1, X2,X3$. Define $Z$ as:  $Z=X1+X2+X3$  I want to force $Z$ to equal 1 for every "realization" of $X1,X2,X3$ ($X_i \sim Beta(a_i,b_i))$. As an example, let $X_i$ denote the percentage of votes a party will get. In a hypothetical country, there are only 3 parties. Therefore, $Z$ is the total percentage of votes, which equals to 100%. Statistically, how could someone force Z to equal 1, and by simulation or through an analytical expression derive the percentages of party A,B and C?


Deriving Transition Matrix of the Embedded Markov Chain given the generator matrix?

Full Problem: A continuous-time Markov chain has generator matrix  $$Q=     \begin{pmatrix}     -1 & 1 & 0 \\     1 & -2 & 1 \\     2 & 2 & -4 \\     \end{pmatrix} $$  (i) Exhibit the transition matrix of the embedded Markov chain.  (ii) Exhibit the holding time parameters for each state.    OK, I must be misunderstanding something. I have the following for the embedded chain transition probabilities:  $$P_{ij} = \frac{q_{ij}}{q_i}$$  where $q_i$ is the parameters of the exponential length of time that the process stays in i.  The problem is that I know $q_i$ is the minimum with exponential distribution and parameter $\sum_k q_{ik}$.  But when I calculate $P_{11}$ that gives me $-1$ which is impossible..  Obviously there is an error in my thinking but can anyone shine light on what I'm misunderstanding? Thank you greatly in advance.


How far away is the Gnome's "Clockwork Toy" or "Music Box" audible?

Rock Gnomes possess the capability to produce small devices such as the "Clockwork Toy", "Fire Starter" and "Music Box". The book specifically states that they produce sound. My expectation on how I would personally use this is as a distraction. So from how far away are these devices Audible?


App is crashing , Null pointer exception . List view is giving the null exception

One activity in my project is crashing. LogCat says "Null EXception " . Simple Adapter giving null exception. I have posted the feed_activity.java and feed_activity.XML file .  import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.widget.ListView; import android.widget.SimpleAdapter;  import com.parse.FindCallback; import com.parse.ParseException; import com.parse.ParseObject; import com.parse.ParseQuery; import com.parse.ParseUser;  import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; public class FeedActivity extends AppCompatActivity {  @Override protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setTitle("Your Feed");     setContentView(R.layout.activity_feed);     final   ListView listView =  findViewById(R.id.listview);     final  List<Map<String,String>> wordData= new ArrayList<>();                 for (int i=1;i<=5;i++){                   Map<String,String> wordInfo = new HashMap<>();                   wordInfo.put("content","word                    content"+Integer.toString(i));                   wordInfo.put("username","user"+Integer.toString(i));                   wordData.add(wordInfo);                 }     SimpleAdapter  simpleAdapter = new SimpleAdapter(this,      wordData,android.R.layout.simple_list_item_2, new String[]     {"content","username"}, new int[]     {android.R.id.text1,android.R.id.text2});     listView.setAdapter(simpleAdapter);             }         }   [LogCat for feedactivity][2] XML Activity_feed :- ListView is used inside a constraint layout .  <?xml version="1.0" encoding="utf-8"?>  <android.support.constraint.ConstraintLayout   xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:app="http://schemas.android.com/apk/res-auto"  xmlns:tools="http://schemas.android.com/tools"  android:layout_width="match_parent"  android:layout_height="match_parent"  tools:context=".FeedActivity">  <ListView     android:id="@+id/listView"     android:layout_width="395dp"     android:layout_height="590dp"     android:layout_marginStart="8dp"     android:layout_marginTop="5dp"     android:layout_marginEnd="8dp"     android:layout_marginBottom="8dp"     app:layout_constraintBottom_toBottomOf="parent"     app:layout_constraintEnd_toEndOf="parent"     app:layout_constraintHorizontal_bias="0.0"     app:layout_constraintStart_toStartOf="parent"     app:layout_constraintTop_toTopOf="parent"     app:layout_constraintVertical_bias="1.0" /> </android.support.constraint.ConstraintLayout>


What happens to light as it passes through a medium?

Light travels at its maximum speed in a vacuum. But when it enters a medium such as glass, air, water, etc. it slows down. What is actually happening to the photons as they pass through the medium? Are they being absorbed by the atoms, exciting the electrons and after some time somehow being re-emitted in the same direction? Are they travelling at vacuum speed between atoms?


Is it possible for many domain names to share one IP address? For example, www.xjtl.com, www.fmie.com, sdmfl.com, etc.  Hundreds of domain names share just one IP – when you do a DNS query for each of them, the same IP is returned.  Are there any laws or Internet rules that disallow this?


First-order trigonometric differential equation

Find $f(x)$ that satisfies the first-order differential equation: $$f'(\sin^2x)=\cos^2x+\tan^2x\tag{for $0<x<1$}$$


In a book I saw this statement.  Before words beginning with h and not accented on the first syllable, an is often used ; as,   An historical , an hotel.  I want to know whether h in hotel is pronounced or not. I would be really grateful if someone can explain this more.


I want to move(archive) the multiple files from say directory /users/wahasan to /users/wahasan/old. The archive files should be autodated.  files are of the format CHKBOI.pos, CHKUTI.pos, CHKSBI.pos,so on. here CHK and .pos are common in every file name.  I need a single shell script that should move all the files from source directory to destination with date-stamp.


Seeing there are various ways to install on Ubuntu. What are the various ways to uninstall items?  Which ways always work? How can I be sure something was uninstalled?


jQuery validator plugin without using form

I have multiple section is asp.net that submits data in chunk and i want to use jquery validation plugin, but issue is that asp.net wraps everything in form and child forms not wokring right and technically incorrect.  So only alternative is forget about form and implement validation for divs. But all sames i see are using form. As not being not good at jquery i can't figure out how to use this validator on section of page(On div).  Is it possible? or any other good alternative?   Source:


Save BOTH handout + standard beamer pdf outputs

Is it possible to configure LaTeX to simultaneously output a standard .pdf for a presentation and also a handout version?  Platform: Texmaker Compiler: XeLaTeX


Why can't Stack Overflow just email me immediately when someone responds to my questions?    I feel like an a-hole when I find out someone posted on a question I asked a month ago and I only find out because I happened to browse to it. Every other forum does it.


If you're starting a sentence with "and" or another conjunction, must you follow the conjunction with a comma?

When I was a kid, I was always told that starting a sentence off with "and" was improper. However, now it seems as if the consensus amongst members of the English cartel is that it is totally acceptable with one addendum, "you must always follow the conjunction with a comma."  My girlfriend just started a sentence with "and" and she didn't use a comma. Was she wrong? Could someone elucidate on "and", and conjunctions at the start of a sentence, and subsequent commas? Here is the exact context,     Did you see those people giving us the finger? And the counter protest?   Should that and have been followed by a comma?


illustrator cc pathfinder minus front function

I'd like to know what the difference is between click on the Minus Front option in the Pathfinder palette and Alt+click.


I am trying to install the old (holo) version of Google Play Music on my device (  - VERSION    Google_Play_Music_v4.4.811H.526848.apk to be exact ) because I only use local media files and the new orange cremesickle version from the past year or so is terrible at this and I loathe it.  However, my roomates have an All Access Subscription which requires the new version, leading to a lot of tension over what version to keep on the device.  I have read that it is possible to install two versions of an app side by side by changing the package name via APKtool. This seems like a trivial thing to do, but it is not working for me.  Following the guide at  i attempted to change the package name, but the line 'cur_package_name' and 'orig_package_name' are not in my apktool.yml, and there is an additional 'original-package' entry in the androidmanifest alogside the line with the package attribute.  Also, upon doing the find-replace trick with notepad++ that they mentioned, it is unable to find any occurrences.  Where can I go from here? I attempted to recompile and run the app on the tablet, but it force closes immediately as something is incomplete. Is there a version of this app that is already modded for side by side loading out there? or how can I proceed?


Proof that if $f$ and $g$ are uniformly continous on an interval $(a,b)$ then so is $f+g$.

I'm trying to prove that if $f$ and $g$ are uniformly continuous on an interval $(a,b)$ then so is $f+g$. I have a picture in my head but I can't seem to make it into a formal proof.


Using a particle system to fill up a container

I want to use a particle system to fill a container. The particles are solid objects and not liquid. I just want a container to look like it was filled naturally, and not like a grid. It would be quicker to set up a particle system to do this than to manipulate tons of separate meshes individually. I'm not sure if this can be done in blender, but any help with this would be nice. I also need this to work with the cycles rendering engine.


I am new here and I am wanting to start my own vampire and werewolf roleplay game but I honestly don't know how role playing works. Can someone please explain it to me.


I've got a problem with my apt file sources.list. Whenever I'm trying to update or install something I keep getting this error and I don't know how to fix it. I tried using vi to remove the malformed line but it doesn't get deleted. E: Malformed entry 58 in list file /etc/apt/sources.list (Component) E: The list of sources could not be read.  Thank you in advance.


Java array declaration syntax difference?

Is there any difference in declaring array argument in java like:   public void method(Type[] arg) { ... }    and in that way:   public void method(Type arg[]) { ... }    Just curiosity...


How do I estimate a smooth cdf from a set of observations?

I have a set of observation, let's call it $X$ and would like to fit a cdf to it. $X$ has a distribution which is roughly approximable with the normal distribution. This CDF should correspond to a continuous distribution function.  So far I've used a parametric approach by estimating mean and standard deviation and using a normal cdf but I would like to know what other options are available and how to use them.  How does the set of available option change if I require the cdf to be a smooth curve?


I saw this series incidentally: $$\sum_{n=1}^\infty (\sin n)^n $$ Result from WolframAlpha seems to say the series diverges but I don't know how to prove it. Thanks for any help!


NullPointerException on assigning value of another variable

I am reading a value from application.yml file: This is a global variable. @Value("${config.key}")     public String variable;  for My use case I need to the value of this variable to another global variable: String secondVariable = variable;  logs show that the key is stored inside the variable but I assign secondVariable the value of first it gives null. The secondVariable need to be global as I need to assign it a updated value when the scheduler runs. What is the right way to achieve this?


Python problem: local results cannot be stored in a global list

I am facing a confusing python problem when generating all lists summed to a number with a fixed length using DFS. The problem is that local results (temp variable) cannot be stored in a global list (res). When I print res with print(res, y), there are numbers of lists in the res, however, there is none using return res in the last line (attached figure). class Solution:     def connect(self , m , n ):         res = []         def helper(x, y, res, temp):             if len(temp) == y:                 temp.sort()                 print(temp, y)                 res.append(temp) #+= [temp]                 print(res, y)                 return             if x >= 0:                 for i in range(0, x+1):                     temp.append(i)                     helper(x - i, y, res, temp)                     temp.pop()         temp = []         helper(m, n, res, temp)         return res #len([i for i in res if sum(i) == m])  Solution().connect(5, 3)


Gift tax on gifts from multiple, unrelated individuals

Based on my “pay no tax” research I found this gift law. I think I’m on the right track and would like clarification because, I literally detest the government for very good reasons; not the least of which their employees murdered my son and destroyed my family without consequence. So, to give them even one penny is unacceptable to me.  Can I teach children an invaluable skill for free and provide a website or PayPal link for anyone who appreciates the result of my gift to their child and wishes to gift me money (or maybe they don’t have a child but believe in my revolutionary contribution to the future) as they see fit, up to $10K?


Since 2008 I've been using a Gmail account as my main mailer, and I'm happy with the service. Unfortunately, I'm slowly but surely entering the business world, and my mail uses a children's name (along the lines of DarkShadow). Embarrassing to say the least.  This all wouldn't be a problem if I could just make a new mail, but all of my services, including my YouTube account and a bazillion forums, are linked to that mail. Plus, I have all mails up until the first one from 2008 archived.  Google has a feature to add secondary mails to accounts, but that unfortunately only works partially, because it writes it like " on behalf of ", defeating the whole point.  Is there a feature to migrate absolutely everything to my new mail address? Apart from setting up a universal redirect, I can't think of anything.


Was refused flight registration as a US resident/non-US citizen

I was flying from Kiev through Munich and Frankfurt to US. In Kiev I was refused a registration for the flight by airport official due an absence of Schengen visa. I had also just a carry on language, no check in. I presented my green card, but he said it did not matter. I had to buy another ticket, which was expensive, directly to USA. Was that a correct action of the official?


I tried downloading the zip file but I couldn't find any binary or install file.  Is it available via apt or can we access the latest .deb file somehow?  edit  uname -a      Linux XXXX 2.6.38-11-generic #50-Ubuntu SMP Mon Sep 12 21:17:25 UTC   2011 x86_64 x86_64 x86_64 GNU/Linux


A subset of $[0,1]\times[0,1]$ containing at most one point from each horizontal and vertical section whose boundary is $[0,1]\times[0,1]$

How can one build a subset $A\subset [0,1]\times[0,1]$ containing at the most one point from each horizontal and each vertical section and whose boundary (frontier) is $[0,1]\times[0,1]$?  I don't know how to build this set. I know that if $A$ contains points in each quarter of the square it's enough.


Does .exe setups work? On windows if I need a software I just download it from filehippo and install it but is it the same on Ubuntu.


I'm trying to parse a string object that carries simple XML.  I have parsed XML files at the past but I can't use the code because it refers to files and not strings- please review the code I used for files and let me know how can I parse the same way string  object  code example:  DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance(); DocumentBuilder dBuilder = dbFactory.newDocumentBuilder(); Document doc = dBuilder.parse( GET_XML.toString()); doc.getDocumentElement().normalize();   xml example:  <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <TccSubscriptionData xmlns="tcc.generated.interfaces.com">     <MessageKey>         <MessageKey>12</MessageKey>         <Receiver>sc</Receiver>         <Timestamp>2018-06-20T14:33:22.968+02:00</Timestamp>         <ResponseType>Subscription</ResponseType>         <CorrelationId>0</CorrelationId>     </MessageKey> </TccSubscriptionData>


How to derive a hash function from another hash function?

Problem: Hash functions derived from another hash function (4 marks) Suppose that $H:\{0,1\}^* \rightarrow \{0,1\}^n$ is a collision resistant hash function. Define a new hash function by $G:\{0,1\}^* \rightarrow \{0,1\}^n$ such that $G(x) = H(H(x)).$ Prove tht $G$ is also collision resistant    I'm trying to figure out how to solve this, apparently, it's hashing the hash value itself. So G has two rounds of hashing the original message x. I tried searching for the relationship properties that I could use to achieve this   Collision resistance implies 2nd-preimage resistance  If the output values of 𝐻 are uniformly distributed, then collision resistance implies preimage resistance  If the output values of 𝐻 are uniformly distributed, then 2nd-preimage resistance implies preimage resistance  Preimage resistance does not imply 2nd-preimage resistance  2nd-preimage resistance does not imply collision resistance   But I didn't find anything I could use, I'm really having trouble, so I'd appreciate any help.


Proving this inequality that involves the Trace of matrices

Let $A, B \in M_n(\mathbb{C})$ be Hermitian. Show that $\text{tr} (AB)^2 \leq \text{tr} (A^2B^2$).  What we can say is that $AB - BA$ is skew-hermitian since $BA = (AB)^*$. Since it is Skew-hermitian, its eigenvalues are all imaginary. And its square is similar to a diagonal matrix whose diagonal entries are all negative. And so $\text{tr}(AB-BA)^2 \leq 0$.  How do you proceed from here?


Problem with bleutooth on Lenovo G510 and Ubuntu18.04

I have problem with bluetooth at Lenovo G510. I can turn on bluetooth but it can not find any device. I tried this solution , and it worked for one day. Next day Ubuntu made small update and bluetooth crashed. Please help me to resolve this problem. If you need output from commends i can execute and place inside post. Instruction: lspci -knn | grep Net -A3; lsusb; dmesg | grep -i blue  gave me: 08:00.0 Network controller [0280]: Broadcom Inc. and subsidiaries BCM43142 802.11b/g/n [14e4:4365] (rev 01)     Subsystem: Lenovo BCM43142 802.11b/g/n [17aa:0611]     Kernel driver in use: wl     Kernel modules: wl Bus 002 Device 002: ID 8087:8000 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 002: ID 8087:8008 Intel Corp. Integrated Rate Matching Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 003 Device 004: ID 0bda:0129 Realtek Semiconductor Corp. RTS5129 Card Reader Controller Bus 003 Device 006: ID 105b:e065 Foxconn International, Inc. BCM43142A0 Bluetooth module Bus 003 Device 003: ID 045e:0745 Microsoft Corp. Nano Transceiver v1.0 for Bluetooth Bus 003 Device 002: ID 5986:0295 Acer, Inc Lenovo Integrated Webcam Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub [  111.627937] Bluetooth: Core ver 2.22 [  111.627958] Bluetooth: HCI device and connection manager initialized [  111.627962] Bluetooth: HCI socket layer initialized [  111.627964] Bluetooth: L2CAP socket layer initialized [  111.627969] Bluetooth: SCO socket layer initialized [  111.774197] Bluetooth: hci0: BCM: chip id 70 [  111.775192] Bluetooth: hci0: BCM: features 0x06 [  111.791305] Bluetooth: hci0: abcd-Lenovo-G510 [  111.791314] Bluetooth: hci0: BCM (001.001.011) build 0000 [  111.803491] bluetooth hci0: Direct firmware load for brcm/BCM.hcd failed with error -2 [  111.803495] Bluetooth: hci0: BCM: Patch brcm/BCM.hcd not found [  113.834314] Bluetooth: hci0: command 0x1003 tx timeout [  113.835288] Bluetooth: hci0: unexpected event for opcode 0x1003 [  211.634168] Bluetooth: BNEP (Ethernet Emulation) ver 1.3 [  211.634170] Bluetooth: BNEP filters: protocol multicast [  211.634174] Bluetooth: BNEP socket layer initialized [  211.651277] Bluetooth: RFCOMM TTY layer initialized [  211.651285] Bluetooth: RFCOMM socket layer initialized [  211.651289] Bluetooth: RFCOMM ver 1.11 [  213.663101] Bluetooth: hci0: command 0x1003 tx timeout [  213.664288] Bluetooth: hci0: unexpected event for opcode 0x1003 [  412.849614] Bluetooth: hci0: BCM: chip id 70 [  412.850548] Bluetooth: hci0: BCM: features 0x06 [  412.866557] Bluetooth: hci0: abcd-Lenovo-G510 [  412.866563] Bluetooth: hci0: BCM (001.001.011) build 0000 [  412.866585] bluetooth hci0: Direct firmware load for brcm/BCM.hcd failed with error -2 [  412.866588] Bluetooth: hci0: BCM: Patch brcm/BCM.hcd not found [  414.887733] Bluetooth: hci0: command 0x1003 tx timeout [  414.888569] Bluetooth: hci0: unexpected event for opcode 0x1003


Let $C_b((a,b))$ be the space of continuous and bounded functions on $(a,b) \subset \mathbb{R}$, let $||f||_\infty := \sup\{|f(x)| : x \in (a, b)\}$. Is ($C_b((a,b)),||\cdot||_\infty)$ a complete metric space? I really have no idea how to proceed with this problem... Sorry for my english skills, english is not my first language...


Function continuous at irrationals and discontinuous at rationals

Q: Given the function $f(x)=\sum_{n=1}^\infty f_n(x)$, where $f_n(x)=      \left\{      \begin{array}{lr}        0;   \;\;if  \;x< r_n \\        \displaystyle \frac{1}{2^n}; x\geq r_n      \end{array}    \right.   $  Here $r_n$ is an enumeration of $\mathbb{Q}$. Show that $f(x)$ is contionuous at irrationals and discontinuous at rationals.  Here is my work. I proved that each $f_n(x)$ is continuous at irrationals. But now stuck in proving $f(x)$ continuous at irrationals. Can anyone please help me?


I have some code. In main function i push six element in BST. when i look to debugger, i see that variable  size = 5, but variable root = null. Why variable root not change.  package Search;  public class BST<Key extends Comparable<Key>, Val> { private class Node{     Key key;     Val val;     Node left;     Node right;     Node prev;     Node(Key k, Val v){         key = k;         val = v;     } } public void push(Key k, Val v){     push(root,k,v); } private void push(Node x, Key k, Val v){     if(x == null){         x = new Node(k,v);         size++;         return;     }     int cmp = x.key.compareTo(k);     if(cmp > 0)         push(x.left,k,v);     else if(cmp < 0)         push(x.right,k,v);     else         x.val = v;  } Node root = null; int size = 0; public static void main(String args[]){     BST<String,Integer> bst = new BST<String, Integer>();     bst.push("c",1);     bst.push("b",2);     bst.push("d",3);     bst.push("a",4);     bst.push("e",5);     bst.push("c",6); }   }


Array.filter duplicates when returned variable changes

Note: I am using react, hence please consider the family array as props.family.  Issue:    Step1: Pass an number argument to getRowData(). Step2: We will get the result stored in filteredData variable as an array. Step3: Now I try to add a new data to filteredData[0] which doesn't exist before. Step4: Value of filteredData[0] changes as expected, However the same value is reflected in matching family array aswell.   Expected: Change only the filteredData array, family array should never change unless I directly change it.              var family = [{"name":"Jack",  "age": 26},                           {"name":"Jill",  "age": 22},                           {"name":"James", "age": 5 },                           {"name":"Jenny", "age": 2 }];              const getRowData = age => {                 const tmpval = [...family];                 return tmpval.filter(members => members.age > age);               };              const filteredData = getRowData(18);             //Everything works perfectly till the above line.              filteredData[0].number = '1';             console.log(filteredData);             console.log(family);             //The number field and value will reflect in both filteredData and family array aswell.   Please help me understand better. The filter function better, filteredData becomes a shallow copy of family array.


How to always run as administrator applications on Windows

The problem is, when I open applications I need to always right click, select run as admin.     When I don't do it getting unexpected application errors. BTW, I turned off UAC.   It's annoying. Is there any way to change behavior of double left-click to act as "Run as administrator" action? I mean to make "Run as administrator" action by default. Thx in advance


Image before adjustments:-   Image after adjustments:-   How would I achieve this effect in Photoshop?


I'm using the online tool shareLatex, when I compile the document I have some random blackbox appears in the right-side of the document. I have no errors in the document. Does anyone knows what is the reason of these black boxes.


Prove that A×(B∩C) = (A×B)∩(A×C) by using the set builder notations.  I know how to prove this using containment proof but am lost on how to prove it using set builder notations. What would a proof like this look like?  Can anyone help me with this or give me a clue on how to start with this notation?


When can I treat infinitesimals as numbers?

Even if many mathematicians don't like the notation, I have found in many rigorous math books things like  $\frac{dy}{dx}=Ay$  so  $\frac{dy}{y}=Adx$  What I don't understand is this:  under which conditions is ok to treat infinitesimal as numbers ? (multiplying for example both sides of an equation by dx).  Edit:  Not only, what allows me to integrate both sides of the last equation ???


If $\mathcal{E}$ are subsets of $X$ and $A \subset X$. Show that $\mathcal{A}\mathcal{(E \cap}$ A)=$\mathcal{A}\mathcal{(E)} \cap$ A

If $\mathcal{E}$ is collections of subsets of a set $X$ and let $A \subset X$ be a subset. Show that the generated $\sigma$-algebra of $\mathcal{(E \cap}$ A) =the generated $\sigma$-algebra $\mathcal{E}$ $ \cap A$, i.e.,   $\mathcal{A}\mathcal{(E \cap}$ A)=$\mathcal{A}\mathcal{(E)}  \cap$ A


Is it safe to publicly share Minidump files?

Is it safe to publicly share Minidump files which are created after windows crash for like diagnosing let's say posting there links here at SO so other users can have a look and diagnose the issue??  Does those files contain information such as username, password, ip etc. that can compromise the security of one?


Windows 7 "Waiting for background program to close"

I am using Windows 7 Home Premium. When I shut down my computer why does the screen show this:    Before shutting down I'm close all programs.


I get this error message   NMI watchdog: BUG: soft lockup - CPU#2 stuck for 23s! [plymouthd:305]    on the startup of my system (even with live-cd).  My PC is a dell inspiron 7559 with intel graphic and nvidia.  UPDATE - this issue also happens when attempting to install ubuntu 18.10 using LiveUSB


Is there any way that one could bind a parameter directly to the connection variable so it could be replaced in every prepared statement?  Could this work? :  $database = 'users'; $pdo_conn = connection variable; $pdo_conn->bindValue(':usersdb', $database, PDO::PARAM_STR);  // Query $pdo_query = $pdo_conn->prepare("SELECT * FROM :usersdb.users");   Thanks in advance!


I want to start using TEX to write up assignments and labs

I want to start coding in my assignments and lab reports in TEX (I'm not sure that's the correct software name) as they look more professional.  The only TEX knowledge I have is writing mathematical equations like:   $$ \lim_{h \to 0} \frac{f(x+h)-f(x)}{h} $$   As for coding experience goes, I have done programming in C and C++ before.   My question is then:  What program or online editor is the best to use? and where can I find some good tutorials?   (I'm sorry that my Tag does not relate to what I'm asking, I don't know what the appropriate tag is.)


I am sculpting a column and noticed, that my edges vertically are very smooth, but when I do them horizontally they are rough. I want them smooth and clean, but I don't want to use the smoothing-brush. It just should work look the horizontal line. Why do they look different and how can I achieve the clean edges? Thank you for helping!


Sickbeard and Sabnzbdplus won't start at boot

I seem to have some problems with automating some services at startup. I've had this problem before, but I couldn't find out the exact reason what caused this.  I've added both services to startup with:   $ sudo update-rc.d sickbeard defaults   Then:  $ sudo service sickbeard status  * sickbeard is not running  $ sudo service sabnzbdplus status  * SABnzbd+ binary newsgrabber: not running  $ service --status-all   [ + ]  acpid  [ - ]  rsync  [ + ]  rsyslog  [ - ]  sabnzbdplus  [ + ]  saned  [ ? ]  sendsigs  [ - ]  sickbeard   (list is truncated) Screenshot from jobs-admin:   As you can see the app is not starting at boot... What might be causing this?


I need an algorithm that can determine whether two images are 'similar' and recognizes similar patterns of color, brightness, shape etc.. I might need some pointers as to what parameters the human brain uses to 'categorize' images. ..   I have looked at hausdorff based matching but that seems mainly for matching transformed objects and patterns of shape.


Mathematical software for calculating Christoffel symbols, curvature, etc

I'm looking for a Mathematical software that can do the following:  I put in a metric (some kind of a two-dimensional matrix), and the software calculates Christoffel symbols, Ricci curvatures, Paneitz operators, etc.  What software should I use? Can I do this somewhere online?


Do Overwatch characters say different things when they cast their ultimate?

This is for Mei  Dòng zhù! Bùxǔ zǒu! (self and hostile)  Freeze! Don't move! (friendly)    What actually happened?  Mei just screamed a sentence and all her foes will listen to Dòng zhù! Bùxǔ zǒu! and her friends will listen Freeze! Don't move!  Or Mei shout two sentences. One to her friends' headsets and the other to his foes headsets?  What actually happened?  Or it's just a game mechanic. The foes listen to hostile?  Realistically I see no reason why a character would bother "warning" their opponents before killing them. But how is this actually done in game.


What does ex - muslim pakistani mean grammatically. Does it mean ex muslim ex pakistani?

If ex is followed by two words or adjectives, then does ex imply to the first adjective only or it will be applied to second adjective aswell e.g, ex-muslim pakistani.


How do I restrict my kids' computing time?

Access to our computer (not only to the internet) needs to be restricted for the accounts of my kids (7, 8) until they are old enough to manage this by themselves. Until then we need to be able to define the following:   the hours of the day when computing is o.k. (e.g. 5 - 9 pm) the days of the week when computing is not o.k. (e.g. mondays to fridays) the amount of time allowed per day (e.g. 2 hours)   In 11.10 all of the following that used to do the job don't work any more:   : for > 11.10 no more available through the ppa. : command line alternative, but from 11.10 removed from the repositories. : Looks great but repeatedly crashes to force restarting X-server. So we can't use or recommed this program at the moment.   Are there any other alternatives?


Text files - how to programmatically mimic opening in Wordpad and overwriting as plain text

My app writes the contents of text files to a db memo field. Most files display properly in the db form, but some display in a run-on fashion (all contents on one line). If I open these files in Wordpad they display correctly, so I save them as plain text to make them display properly in the db form.  I'm tired of doing this :-) and would like to perform this "conversion" programmatically. Using the "analyze the bom" method I found online, it says both types of files are ASCII.  Trying to load a problem file into a RichTextBox as rich text returns "input file not in correct format". Using the immediate window in debug, I've found the files that display properly use \r\n for newline, and the ones displaying improperly use only \n.  Using Regex.Replace \n, \r\n just causes the \r\n to appear visibly as text (rather than encoding characters). The question "Text shown in single line in notepad" seems to be the same type of issue, except the file is being streamed and massaged line-by-line, which I'm thinking shouldn't be necessary.  So... all I need to do programmatically is to somehow mimic the behavior of opening the file in Wordpad and overwriting it as plain text.  I've experimented extensively (unsuccessfully) with Encoding.Convert and the thing that really baffles me, is that the problem files appear to be ASCII encoded just like the "good" files, only difference is that the good files use \r\n where the problem files use just \n.  Any help is appreciated...  For what it's worth, this is the statement that's loading the text file contents into the temporary string array (whose contents are later loaded to db). I realize I might need to ReadAllText into a "work" string and massage it before loading it to the array... but the only massaging it needs is to be opened in Wordpad and then overwritten as plain text. If only I could figure out how to do that!  txtfileary[aryctr] = File.ReadAllText(textfile, Encoding.ASCII);


I have a vacuum sealed 8 lb. beef tenderloin that was in my refrigerator.  The door was not closed completely and the refrigerator warmed to 42 degrees just at the beginning of the danger zone.  The refrigerator could have been at that temp for 6 to 8 hours.  The tenderloin was in the middle back of a bottom shelf.  Is this safe to use?


Finding contiguous ranges in grouped data

I have a table with the following structure:  CREATE TABLE `Rings` (     ID_RingType CHAR(2),     Number MEDIUMINT UNSIGNED,     ID_User INT(11) );   and with data:  INSERT INTO `Rings` VALUES   ('AA',1,1),   ('AA',2,1),   ('AA',3,1),   ('AA',11,1),   ('AA',12,1),   ('AA',13,1),   ('AA',14,1),   ('AA',15,1),   ('AB',16,1),   ('AB',17,1),   ('AB',18,1),   ('AB',19,1),   ('AB',20,2),   ('AB',21,2),   ('AB',22,2);   I wish to group the data based on ID_User and ID_RingType and for each contiguous range of numbers list the MIN and MAX.  The results should look like:  ID_User | ID_RingType | MIN  | MAX 1       | 'AA'        | 1    | 3 1       | 'AA'        | 11   | 15 1       | 'AB'        | 16   | 19 2       | 'AB'        | 20   | 22   I went through several posts on this topic but was not able to tweak them to fit my data.  Any help would be appreciated.


How to generate Table of Contents on left side of Preview?

It's easy to generate a Table of contents inside a LaTeX document using "\tableofcontents", but when opened in Preview on Mac (Preview is an app to view PDF), The left side doesn't show any table of contents. Here is an example of what I want:  Do you know any package or setting step that can generate this kind of table of contents? Thanks.


How to install custom fonts in Ubuntu 20.04?

I want to install the secondary font in ubuntu, I have downloaded it locally. How I can install it?


btrfs with multi devices fails automount in fstab

I'm trying to automount btrfs  on 12.04-desktop-amd64. During bootsplash, fstab failed to mount btrfs and asked skip or manually prepare.  On the rootshell, btrfs device scan and mount -a could automount properly. It seems "btrfs device scan" was missing from bootstrap.  Where should I add the line to prepare bootstrap?


Let ${X_1},...,{X_n}$ be a random sample from uniform distribution   $U\left[ {0,\theta } \right]$. Find the MLE of $\theta $.   I wrote the likelihood function of this distribution, that being a uniform one has $f\left( x \right) = {1 \over {b - a}} = {1 \over \theta }$ as $$l\left( \theta  \right) = \prod\limits_{i = 1}^n {{1 \over \theta }} $$  which has an equivalent loglikelihood function  $$\log \left( l \right) = \sum\limits_{i = 1}^n {\left[ {\log \left( {{\theta ^{ - 1}}} \right)} \right]}  =  - n\log \left( \theta  \right)$$  Now if I want to find the MLE, I'll set its first derivative to zero: $$\eqalign{   & {\partial  \over {\partial \theta }}\left( { - n\log \theta } \right) = 0  \cr    & {{ - n} \over \theta } = 0 \cr} $$  And that's where things stopped making sense for me, for I can't solve for $\theta $ like I normally can (for other distributions). Checking a bunch of different threads in this community, apparently writing $\theta  = {X_{(n)}}$, that is, the highest observation from the sample, is enough as an answer.   However, I can't stop thinking about the fact that no ${X_{(n)}}$ on the planet would make the first derivative be equal to zero, so how can that be a valid estimator?


I use youtube-dl to download videos for watching later offline. Usually, it works fine. However, due to frequent changes on the video sites, it sometimes requires a quick update. It wasn't a problem before on 13.04 but after upgrading to 13.10, I get  # youtube-dl -U It looks like you installed youtube-dl with a package manager, pip, setup.py or a tarball. Please use that to update.   I tried updating it via apt-get but there is no new package. So the app's update mechanism has been disabled and the maintainers aren't keeping up, what is the solution? How do I update it?  And why was it changed at all? It was updating a package manager version just fine in raring.   I'm already running into compatibility problems.   $ youtube-dl "http://vimeo.com/55784152" [vimeo] 55784152: Downloading webpage [vimeo] 55784152: Extracting information ERROR: Unable to extract info section; please report this issue on https://yt-dl.org/bug . Be sure to call youtube-dl with the --verbose flag and include its complete output. Make sure you are using the latest version; type  youtube-dl -U  to update.   QUICK UPDATE:  As requested,  # type youtube-dl youtube-dl is hashed (/usr/bin/youtube-dl)  # apt-cache policy youtube-dl youtube-dl:   Installed: 2013.08.29-1   Candidate: 2013.08.29-1   Version table:  *** 2013.08.29-1 0         500 http://pl.archive.ubuntu.com/ubuntu/ saucy/universe amd64 Packages         100 /var/lib/dpkg/status


What do the brackets around processes mean?

$ ps -Awwo pid,comm,args   PID COMMAND         COMMAND     1 init            /sbin/init     2 kthreadd        [kthreadd]     3 ksoftirqd/0     [ksoftirqd/0]     5 kworker/u:0     [kworker/u:0]     6 migration/0     [migration/0]     7 cpuset          [cpuset]     8 khelper         [khelper]     9 netns           [netns]    10 sync_supers     [sync_supers]    11 bdi-default     [bdi-default]    12 kintegrityd     [kintegrityd]    13 kblockd         [kblockd]    14 kacpid          [kacpid]    15 kacpi_notify    [kacpi_notify]    16 kacpi_hotplug   [kacpi_hotplug]    17 ata_sff         [ata_sff]    18 khubd           [khubd]   What do the brackets mean? Does args always return the full path to the process command (e.g. /bin/cat)?


Circuit to construct a $n$-qubit state which is a superposition of states with only a single qubit being $\lvert1\rangle$

So the question came up in a book I am working through. Given a circuit with $n$ qubits, construct a state with only $n$ possible measurement results, each of which has only $1$ of $n$ qubits as $1$, such as $|0001\rangle$, $|0010\rangle$, $|0100\rangle$, $|1000\rangle$, obviously normalized.  The only way I can think to do this is to take the all $|0\rangle$ input state, apply $\operatorname{H}$ to each qubit and then used multiple-controlled $\operatorname{CNOT}$ gates to affect the change on each qubit, but I feel like this won't lead to the desired end state.   To be clear, I am enquiring how to create a $W_n$ state can be arbitrarily prepared, given $n$ qubits.


According to the statistics displayed on my suggested edits. I mean    According to what is shown above. I have 120 edit suggestions approved but in my badge progress     Its shows 82 edits.  I even just got my  Badge. My Question is how are edits counted and what is the reason for the inconsistency?


Which object does `this` refer to inside an event handler?

Does it refer to the object the handler it is defined in or the object than handle belongs to:  example:  class foo   {  Object a;  public foo()  {   a.handle += function;      }   void function()  {        this;<--What does this "this" refer to foo or object a?  }     }


Can just make or design the photo in 72dpi, and just change it to 300dpi later on?

:) I'm not a professional graphic designer or anything but I love making stuff on photoshop. I have a problem here with DPI & printing. I want to make a 24 " x 36" canvas for my friend's birthday this June. I've been 'designing' in photoshop for fun and for web only. I'm kind of new to making a design for print.  From what I have read through the internet, 300dpi is the best resolution for printing, yes? But when I tried to input 36 x 36 inches in 300dpi resolution in photoshop, the file is HUUUUGE. Gigantic. The image that I have to design just looks like a dot on it. T__T  I was wondering if I can just make or design the photo in 72dpi, and just change it to 300dpi later on? Would it work or is it just a fool's hope?   Could someone with a good heart please enlighten me on photoshop & prints? I would really appreciate all the help I can get. I am really confused on this one. Thank you so much. :)


Is it possible to have multiple stop codons in one exon?

I would be very happy if someone can help me to find the answers for the following related questions.   Can one exon have many stop codons? Can protein synthesis happen, if the stop codon is at the beginning of the exon?


How can I position equation numbers always to the left side?

Equations and amsmath environments put equation numbers to the right side by default, the output of  \begin{multline}   some equation \end{multline}   is:  equation (number)   How can I change it this way:  (number) equation


Adverb order: 'has largely been' or 'has been largely'

Does the placement of an adverb affect its meaning or application? Does each paired sentence here mean the same as the other?      1.1 Mobile technology progress has largely been consumer-driven rather than enterprise-driven.   1.2 Mobile technology progress has been largely consumer-driven rather than enterprise-driven.        2.1 Mobile technology progress has largely been shaped by consumers.   2.2 Mobile technology progress has been largely shaped by consumers.


I was reading the discussion about "" and noticed that several types of flour were mentioned.  I looked at my bread flour and noticed that it says 4%.  I looked at the AP flour, a common brand, it says 3%. My question is, is it possible to add gluten to increase the protein content in the flour?  I am relatively new at making bread.  I am trying to bake an Italian recipe for crusty bread by translating the ingredients into what is available in the US.  The recipe calls for Flour 00.  Thanks for the advice.


How do I delete unique rows from a table with duplicate keys?

I have the following data:        road        |  ID  | other column  | other column |  ------------------+------+---------------+--------------+           MAIN ST           |  1   |     ...       |     ...      | MAIN ST           |  2   |     ...       |     ...      |         MAIN ST           |  3   |     ...       |     ...      | BERRY LN          |  4   |     ...       |     ...      | BERRY LN          |  5   |     ...       |     ...      | BERRY LN          |  6   |     ...       |     ...      | JOHN RD           |  7   |     ...       |     ...      | JOHN RD           |  8   |     ...       |     ...      |   I want all rows with duplicates in the road column removed. It does not matter to me which duplicates are removed. The end result can look something like this:        road        |  ID  | other column  | other column |  ------------------+------+---------------+--------------+           MAIN ST           |  3   |     ...       |     ...      | BERRY LN          |  4   |     ...       |     ...      | JOHN RD           |  8   |     ...       |     ...      |   where the id's are any value, as long as the road column is unique.   Is there a simple way to do this in SQL or T/SQL? I followed the guide , but it only applies to duplicate keys with non-unique rows.


What's the past participle form of the word exit? Is it exit (irregular, like set)? exited? exitted? On one page I found exited but if that's the case why isn't it exitted (double t) like with the word emit - emitted? Is there a rule when the consonant at the end is doubled and when not?


Checking for an Internet connection before executing a page refresh

I know this question has been discussed many times but there does not seem to be a universal working answer.   I have a web page that displays data which is continually updated and I need to work out how I can prevent the web page from refreshing if there is no internet connection.   I have tried many different approaches but without exception, went I disable my internet connection, browsers displays   Firefox: Server not found   Chrome: There is no internet connection   IE: You’re not connected to the internet   I have looked into various browser plug-ins but none of them work.   I have taken a look at navigator.onLine but even using this browsers still display their own not connected pages. I have looked at using some sort of AJAX call without any success.   I do not need to worry about who is using which browser because this script is going to run on a known device configured to a known specification.   Is there a full proof method of preventing a page refresh until there is a connection?  loadDoc("example.com/comms_true.png", myFunction1); function loadDoc(url, cFunction) { var xhttp; xhttp=new XMLHttpRequest(); xhttp.onreadystatechange = function() { if (this.readyState == 4 && this.status == 200) { cFunction(this); setTimeout(function() { location.reload(); }, 30000); } else { } }; xhttp.open("GET", url, true); xhttp.send(); }  function myFunction1(xhttp) { setTimeout, 30000; }


When is $F(x)=x^a\sin(x^{-b})$ with $F(0)=0$ of bounded variation on $[0,1]$?

I'm trying to show that $F(x)=x^a\sin\left(x^{-b}\right)$ for $0<x \leq 1$ and $F(0)=0$ has bounded variation only if $a>b$.      I know I have to show there exist an $M< \infty$ such that for any partition $0=t_0<t_1<...<t_n=1$ we have  $$\sum_{j=1}^N |F(t_j)-F(t_{j-1})|<M \iff |F(t_1)| + \sum_{j=2}^N |F(t_j)-F(t_{j-1})|<M .$$  I'm stuck here.


Is there a pair of alien species, one in Star Wars, one in Star Trek, that are too similar for coincidence?

We all know that there are a huge number of different alien species created for the Star Wars and Star Trek universes. I'm wondering if there's a pair of species that are so similar, it doesn't seem like it can be a coincidence.  The creators may be influenced, intentionally or not.   Or if there's evidence of plagiarism, that would be a good part of an answer. Before someone answers "people":  In order to satisfy the question, it means the candidates can't be human (obviously) and can't match some simple description whose conception predates Star Trek and Star Wars (examples: human with green skin; anthropomorphic lizard, etc).


Interpretation of interaction term in R lm(): .L .Q

I ran a regression in which I have an interaction term of two factor variables.  The one of the variables has 2 levels: Condition_A & Condition_B (therefore the first one is the reference category) but the other one is called Group.Membership has 3 levels: Group_1, Group_2 & Group_3 (therefore the first one is the reference category).  What I am not sure about is how to interpret the output. What I get as part of the lm() ouput is :       ConditionB:Group.Membership.L         (Beta and p-value)     ConditionB:Group.Membership.Q         (Beta and p-value)   Should I interpret the .L as the coefficient for Group_2 compared to the reference category (Group_1), and the same goes for .Q? Or there is another interpretation of this type of output?  Thank you for your help!  EDIT ----------------  I have another question. I have tested the interaction term of the Condition variable with many other factor variables. Why sometimes I get in the ouput the .L and .Q in the end, whereas in other occasions I get the levels of the second variable of the interaction term without the .L and Q.? Am I doing something wrong in my lm() ?


Im a newbie here.I need help how to decode a html string "&#128081" to char in c#? it should be show crown character or if its not supported it should show a rectangle.Im working for iOS.  Thank you for all your help.


I am very new to Mac and Apple world, please excuse me for my ignorance if any. I do see Macbook pro or Air doesn't come with Hard Disk drive..!! It comes with flash storage with just storage like 128GB etc (which is very low I feel). Can anyone let me know why no Hard Disk on Macbook pro? Is it possible to install third party hard disk to it?


Order of any element divides the order of the group proof

Show that the order of any element $g \in G$ divides $n$, where $n$ is the order of a group $G$.   So far I have shown that: $G$ - finite group and let $g \in G$, therefore, the order of the subgroup generated by $g$ equals the order of $g$. Using Lagrange's Theorem we get that the order of $g$ divides $n$, which we had to prove. Is this a valid proof or am I missing something? Any ideas?


How to find the limit of $a_1=1\:,\:a_{n+1}=\frac{a_n+2}{a_n+1}$?  I think to find the limit, first I need to prove that the sequence is convergent then it is easy to find the limit :   $L = \frac{L+2}{L+1}  \to  L = \sqrt{2}$ because the sequence $>0$   any hint to prove that the sequence is convergent?   thanks


Increasing display to higher resolution to capture HD screenshot

I am using an HP laptop with Windows 10, this is showing maximum screen resolution of 1366x768. I see that this is maximum available display:     However, I require a minimum of 1920×1080 screen resolution to capture web page screenshots.  If I have to install additional software or hardware, so that I can increase resolution?


Looking for help with a proof that n-th derivative of $e^\frac{-1}{x^2} = 0$ for $x=0$.

Given the function   $$ f(x) = \left\{\begin{array}{cc} e^{- \frac{1}{x^2}} & x \neq 0 \\ 0 & x = 0 \end{array}\right. $$  show that $\forall_{n\in \Bbb N} f^{(n)}(0) = 0$.  So I have to show that nth derivative is always equal to zero $0$. Now I guess that it is about finding some dependencies between the previous and next differential but I have yet to notice one. Could you be so kind to help me with that?  Thanks in advance!


Boot partition full, failing to delete old kernels. Broken packages

Sorry for asking about what is probably really simple, but I've been Googling about for a week now and I've tried a lot of stuff without success.  To start off, I get a pop-up every time I boot saying my /boot partition is full, and the Synaptic Manager says linux-image-generic is broken, but it fails to reinstall either of them (linux-image-extra-3.13.0-54-generic and linux-image-generic).  My terminal tells me to try using install -f to fix things so I've tried that, and this is what it returned. Sadly, I'm still learning and I haven't been able to crack the code, I would like some help  aksel@aksels-PC:~$ sudo apt-get install -f Reading package lists... Done Building dependency tree        Reading state information... Done Correcting dependencies... Done The following extra packages will be installed:  linux-image-3.13.0-54-generic Suggested packages:  fdutils linux-doc-3.13.0 linux-source-3.13.0 linux-tools The following NEW packages will be installed:  linux-image-3.13.0-54-generic 0 upgraded, 1 newly installed, 0 to remove and 344 not upgraded. 5 not fully installed or removed. Need to get 0 B/14,7 MB of archives. After this operation, 32,8 MB of additional disk space will be used. Do you want to continue? [Y/n] y (Reading database ... 431129 files and directories currently installed.) Preparing to unpack .../linux-image-3.13.0-54-generic_3.13.0-54.91_i386.deb ... Done. Unpacking linux-image-3.13.0-54-generic (3.13.0-54.91) ... dpkg: error processing archive /var/cache/apt/archives/linux-image-3.13.0-54-generic_3.13.0-54.91_i386.deb (--unpack):  cannot copy extracted data for './boot/vmlinuz-3.13.0-54-generic' to '/boot/vmlinuz-3.13.0-54-generic.dpkg-new': failed to write (No space left on device) No apport report written because the error message indicates a disk full error  dpkg-deb: error: subprocess paste was killed by signal (Broken pipe) Examining /etc/kernel/postrm.d . run-parts: executing /etc/kernel/postrm.d/initramfs-tools 3.13.0-54-generic /boot/vmlinuz-3.13.0-54-generic run-parts: executing /etc/kernel/postrm.d/zz-update-grub 3.13.0-54-generic /boot/vmlinuz-3.13.0-54-generic Errors were encountered while processing:  /var/cache/apt/archives/linux-image-3.13.0-54-generic_3.13.0-54.91_i386.deb E: Sub-process /usr/bin/dpkg returned an error code (1)


In Creative mode, do you have to find an End portal to get to the End?

I want to build something in the End in Creative, but how can I access it? Do I have to find an End portal to get to the end? or is there a way to simply go to the end? (Like a command line or something)  Same question could apply if you wanted to go to the nether, do you have to use your creative tools to build a nether portal and then go through, or is there an option to quickly change the world you're into?  PS: I currently am at work and can't try to simply build an end portal, but if I can remember right, if your end portal is not one made by the game, it won't work?


I am trying to install Spotify on Ubuntu 16.04. I type the command into the terminal sudo apt-key adv... etc. and hit enter. It prompts me for the password and when I type on the keyboard nothing happens. How do I get this to work?


Why do electromagnetic waves have the magnetic and electric field intensities in the same phase?

My question is: in electromagnetic waves, if we consider the electric field as a sine function, the magnetic field will be also a sine function, but I am confused why that is this way.  If I look at Maxwell's equation, the changing magnetic field generates the electric field and the changing electric field generates the magnetic field, so according to my opinion if the accelerating electron generates a sine electric field change, then its magnetic field should be a cosine function because $\frac{d(\sin x)}{dx}=\cos x$.


The  says, when use /Z7:     Produces an .obj file containing full symbolic debugging information   for use with the debugger. The symbolic debugging information includes   the names and types of variables, as well as functions and line   numbers. No .pdb file is produced.   Because obj files will be link into exe file finally. So I think the debug info will write into the final building file (exe file).  In , MSDN says:     It is not possible to create an .exe or .dll that contains debug   information. Debug information is always placed in a .pdb file.   After I test it, I found:   whatever /Z7 or /Zi was set, PDB file always get generated.  build with /Z7, and generate a core dump file, use vs open this core dump file, it still need a PDB file to debug.   It seems first msdn doc I refer is outdated.  Can I debugging windows core dump file like linux app which only need a single core dump file? without any additional files like a PDB? Or this is an mission impossible.


18.04 can't turn-on WiFi on Lenovo Ideacentre 510-15ICB

I have Ubuntu 18.04.3 LTS on a new Lenovo Ideacentre 510-15ICB with a Realtek RTL8821CE but I cannot get my WiFi working. The error message is -      no network adapter not found   How do I troubleshoot this?


Perform matrix operations (addition, product, transpose, etc.) in LaTeX?

I know the calc package can perform infix-notation arithmetic in LaTeX... but I want more!  I'd like to perform (not necessarily infix-notation) linear-algebra operations  such as scalar multiplication, matrix addition and product in LaTeX, and then print the result in an array or in some matrix environment from amsmath.  Why would I want to do that in LaTeX directly? Why do I not simply use some linear-algebra software, such as Matlab, Mathematica, etc.?  Well, suppose I want to walk my readers through a detailed linear-algebra calculation with many numerical examples. Of course, I could perform all the steps manually first and then hardcode the result of each step in my input file. However, this approach   is prone to errors (LaTeX' arrays are not very user-friendly to typeset), lacks maintainability (I may decide to change the data in my example, which means I have to modify everything that follows).   Hence my question: Is there a way of easily performing linear-algebra operations in LaTeX?    Ideally, I would like to   mimick Matlab's syntax for defining matrices (using commas as column separators and semicolons as end-of-row characters), performing operations on them, extracting sub matrices, etc.. The syntax could be something like the following:  \let\A{1,2,3;4,5,6} \let\b{1;0;0} \let\c\matrixprod{\A,\b} \let\d\submatrix{\c}{(2,1)}  have a command that typesets a "matrix object" in an array or matrix environment, e.g.  \typesetmatrix[bmatrix]{A}  be able to perform operations on matrices of arbitrary--albeit relatively small--dimensions (edit: not just 2x2 and 3x3 as in the calculator package).   Is that currently possible with some package? If not, I'm considering rolling up my sleeves and implementing something, but this would probably prove quite difficult, and I would like to avoid reinventing the wheel :)    Edit about other operations that would be useful:   diag (extraction of the diagonal of a square matrix) trace  determinant norm(s) condition number(s) inverse   Even more advanced matrix operations that would be awesome, but probably tough to implement:   eigenvalues & eigenvectors, QR, least squares etc. SVD, other common matrix factorisations.


how would i use rm to delete all files without certain wildcard?

using rm *text* you can delete all files which have a certain string in them. How would I make it so that it removes every file except for the ones with the specific wildcard?  I have attempted to use other things I've found, such as:  find . -type f -print0 | xargs --null grep -Z -L 'text' | xargs --null rm   or  grep -r -L -Z 'text' . | xargs --null rm   but these do not work. Instead, they are deleting all files in a given directory.  How could I do this?


Allow only certain hostname in Nginx block

how do you allow only certain hostname in Nginx so that one can only access myhostname.example.net but not example.net?


Why on average does each bootstrap sample contain roughly two thirds of observations?

I have run across the assertion that each bootstrap sample (or bagged tree) will contain on average approximately $2/3$ of the observations.   I understand that the chance of not being selected in any of $n$ draws from $n$ samples with replacement is $(1- 1/n)^n$, which works out to approximately $1/3$ chance of not being selected.   What is a mathematical explanation for why this formula always gives $\approx 1/3$ ?


How can I find out a file's range of LBA's using its inode?

While answering this U&L question titled: , I tried to figure out if it was possible to determine a file's LBA using it's inode.  My answer determined that I could use hdparm as one method for finding LBAs:  $ sudo hdparm --fibmap afile   afile:  filesystem blocksize 4096, begins at LBA 0; assuming 512 byte sectors.  byte_offset  begin_LBA    end_LBA    sectors            0  282439184  282439191          8   But I was curious if there was some method using a file's inode to also get the LBA's; without using hdparm.  I think there might be alternative methods hiding in the tools filefrag, stat, debugfs, and tune2fs but teasing it out is eluding me.  Can anyone think of alternatives?    Here's some of my research thus far that might be useful to those brave enough to attempt to answer this.  filefrag  I suspect you could use the tool filefrag to do it, specifically using the results from its -e switch, perhaps by performing several calculations to get there that I'm not that familiar with.  sample output  $ filefrag -e afile Filesystem type is: ef53 File size of afile is 20 (1 block of 4096 bytes)  ext:     logical_offset:        physical_offset: length:   expected: flags:    0:        0..       0:   35304898..  35304898:      1:             eof afile: 1 extent found   inodes  Another potential method I suspect might have potential is to use a file's inode information, either directly or through some complex math that is poorly documented on the interwebs.  Example  First we find out the file's inode. We can do this using either the stat command or ls -i.  stat  $ stat afile    File: ‘afile’   Size: 20          Blocks: 8          IO Block: 4096   regular file Device: fd02h/64770d    Inode: 6560281     Links: 1 Access: (0664/-rw-rw-r--)  Uid: ( 1000/    saml)   Gid: ( 1000/    saml) Context: unconfined_u:object_r:user_home_t:s0 Access: 2013-12-27 18:40:12.788333778 -0500 Modify: 2013-12-27 18:40:23.103333073 -0500 Change: 2013-12-27 18:44:03.697317989 -0500  Birth: -   ls -i  $ ls -i  6560281 afile   With the inode information in hand, we can now open up the filesystem this file resides on using the tool, debugfs.  NOTE: To determine the filesystem a file resides on you can use the command df <filename>.  Now if we run debugfs and run the command stat <inode #> we can get a list of extents that contain this file's data.  $ sudo debugfs -R "stat <6560281>" /dev/mapper/fedora_greeneggs-home debugfs 1.42.7 (21-Jan-2013) Inode: 6560281   Type: regular    Mode:  0664   Flags: 0x80000 Generation: 1999478298    Version: 0x00000000:00000001 User:  1000   Group:  1000   Size: 20 File ACL: 0    Directory ACL: 0 Links: 1   Blockcount: 8 Fragment:  Address: 0    Number: 0    Size: 0  ctime: 0x52be10c3:a640e994 -- Fri Dec 27 18:44:03 2013  atime: 0x52be0fdc:bbf41348 -- Fri Dec 27 18:40:12 2013  mtime: 0x52be0fe7:18a2f344 -- Fri Dec 27 18:40:23 2013 crtime: 0x52be0dd8:64394b00 -- Fri Dec 27 18:31:36 2013 Size of extra inode fields: 28 Extended attributes stored in inode body:    selinux = "unconfined_u:object_r:user_home_t:s0\000" (37) EXTENTS: (0):35304898   Now we have the extents information above, and this is where I get lost and do not know how to proceed.  References


Is there any  channel for Stack Exchange?  Reason for asking the question:  I was trying to figure out best out of two books which have very less information on Internet in forms of review, etc. So I thought I should ask it on a Stack Exchange site. But I came to know that Stack Exchange doesn't encourage recommendation type questions. That's where the thought of IRC channel came to my mind. I am open to suggestions and any information.


What are the origins of the word orientated?  As far as I know, the correct spelling is oriented and orientated is not an alternative spelling but an error that is in common use.  Is it for example more commonly used in a certain country or by a certain people? Is there a reason for people choosing to say or write orientated instead of oriented?


Prove that $\left| f'(x)\right| \leq \sqrt{2AC}$ using integration

Suppose that $f(x)$ is a $C^2$ function on $\mathbb{R}$ such that $\left| f(x) \right| \leq A$ and $\left| f''(x) \right| \leq C $ for $x \in \mathbb{R}$. Prove that $\left| f'(x)\right| \leq \sqrt{2AC}$.


Name the novel, 197x.  Setting is a world of human(oid)s most of whom have the psi ability to enslave weaker others.  (Maybe the word slave and its derivatives are not used.)  Masters and slaves form a tree rather than a dichotomy; everyone delegates as much as they can. The protagonist is an outworlder on a mission, maybe simply doing a survey.  He wears the green robe of a native subculture who lack the power (or maybe they renounce it?) and are immune to it – by law or custom, I think, rather than by nature. His host or primary contact is Jael Forty of Lant, the number being how many slaves he can control; it can fluctuate.


How would I find the solutions in polar form to $$z^3=-8$$  Can you provide a step by step solution?


Word for intelligence-kind (akin to humankind, but not homocentric)

I am looking for a word that is similar in nature to humankind, but not doesn't focus specifically on humans.  The need arose from a discussion about the meaning of life, where a possible answer is "The betterment of humankind" (what ever that means, doesn't matter).   I am however looking for a word to replace 'humankind' that is more inclusive term, encompassing all kinds of intelligence/forms of consciousness (e.g. other animals, artificial intelligence, aliens).  I preferably looking for a layman term (if possible) that is viable in a non-fiction context.


How to count mutual words in 2 strings in Java?

Say I have two strings:  String s1 = "My name is Alex."  String s2 = "My name is Nick."   I want the program to count mutual words and return the value. With those strings, the returned value would be 3, because of the 3 words both have in common: my, name, is. For some reason, in my program, the num value returned is always 0.  public static int sameWord(String s1, String s2) {      int num = 0;     String[] a = s1.split(" ");     String[] b = s2.split(" ");      for (int i = 0; i < a.length; i++) {          for (int j = 0; j < b.length; j++) {             if (a[i] == b[j]) {                 num++;             }          }     }      return num;  }


I am painting the room in our basement that contains the electrical panel. I think it would look a lot better to paint the panel the same color as the wall, instead of the plain grey-green metal. I've heard that it's against code (USA) to paint the electrical panels, but I wasn't sure why. It's my own house and we don't rent it out, so I'm not too worried about the code violation.  Is there any reason why I shouldn't paint the electrical panel, and are there any problems I should watch for when painting it? The panel is brand new with no rust, so I will likely need to roughen the surface with sandpaper first.


The Cartesian product of a finite number of countable sets is countable

The Cartesian product of a family $(A_i\mid i\in I)$ is defined as $$\prod\limits_{i\in I}A_i=\{f:I\to\bigcup A_i\mid f(i)\in A_i\}$$ Let $I_n=\{i \in \mathbb N \mid i \le n\}$ for $n\in \Bbb N$ and $A_i$ be countable for all $i\in I_n$. Then $\prod\limits_{i\in I_n}A_i$ is countable.   My attempt: Lemma 1: $(\prod\limits_{i\in I_n}A_i) \times A_{n+1}$ and $\prod\limits_{i\in I_{n+1}}A_i$ are equinumerous for all $n \in \mathbb N$. (I presented a proof ) Lemma 2: If $A$ and $B$ are countable, then $A \times B$ is countable. (I presented a proof ) I will prove the theorem by induction on $n$. The theorem is trivially true for $n=0$. Assume that the theorem is true for $n=k$, then $\prod\limits_{i\in I_k}A_i$ is countable. Since $\prod\limits_{i\in I_k}A_i$ is countable (by inductive hypothesis) and $A_{k+1}$ is countable, then by Lemma 2 $(\prod\limits_{i\in I_n}A_i) \times A_{n+1}$ is countable. Furthermore, by Lemma 1 $(\prod\limits_{i\in I_k}A_i) \times A_{k+1}$ and $\prod\limits_{i\in I_{k+1}}A_i$ are equinumerous, then $\prod\limits_{i\in I_{k+1}}A_i$ is countable too. Thus the theorem is true for $n=k+1$. This completes the proof.   Does this proof look fine or contain gaps? Do you have suggestions? Many thanks for your dedicated help!


When I asked here why neutrons in nucleus (with protons) don't decay I was told that it would require energy for the neutron to decay, it wouldn't give energy. And since that wasn't really what I wanted to hear, since I already knew that, I'm now asking a similar question.  I know that strong force holds protons and neutrons together in nucleus, but how does that effect a neutron in a way that it doesn't decay?