Why are rep and badges now collapsed on Safari iPad?

This is the right edge of my topbar, starting today:    Any particular reason why I'm not seeing my total reputation and badges there? Since it's a major part of the "gamification" setup, am I correct in thinking it's a bug? Is it exclusive to Safari iOS?  Update: I highly doubt it's my viewport, since there's plenty of space for it:    If this is a viewport problem, why is there so much space for it?


Conjectures that have been disproved with extremely large counterexamples?

I just came back from my Number Theory course, and during the lecture there was mention of the Collatz Conjecture.  I'm sure that everyone here is familiar with it; it describes an operation on a natural number – $n/2$ if it is even, $3n+1$ if it is odd.  The conjecture states that if this operation is repeated, all numbers will eventually wind up at $1$ (or rather, in an infinite loop of $1-4-2-1-4-2-1$).  I fired up Python and ran a quick test on this for all numbers up to $5.76 \times 10^{18}$ (using the powers of cloud computing and dynamic programming magic).  Which is millions of millions of millions. And all of them eventually ended up at $1$.  Surely I am close to testing every natural number? How many natural numbers could there be?  Surely not much more than millions of millions of millions. (I kid.)  I explained this to my friend, who told me, "Why would numbers suddenly get different at a certain point?  Wouldn't they all be expected to behave the same?"  To which I said, "No, you are wrong!  In fact, I am sure there are many conjectures which have been disproved by counterexamples that are extremely large!"  And he said, "It is my conjecture that there are none! (and if any, they are rare)".  Please help me, smart math people.  Can you provide a counterexample to his conjecture?  Perhaps, more convincingly, several?  I've only managed to find one! (Polya's conjecture). One, out of the many thousands (I presume) of conjectures. It's also one that is hard to explain the finer points to the layman. Are there any more famous or accessible examples?


I want to ask why is $$0! = 1$$ the same as $$1! = 1.$$   As a student I was lost and when I tried to ask the question the teacher said this will be done in complex analysis.  I know here I will thirst my quest by the help of people who understand it.   I know We define $n!$ as the product of all integers k with $1\leq k\leq n$. When $n=0$ this product is empty so it should be 1.   I was just wondering if for factorial we take:  $$6! = 6\cdot 5\cdot 4\cdot 3\cdot 2\cdot 1$$ $$5! = 5\cdot 4\cdot 3\cdot 2\cdot 1$$  In normal multiplication any number multiplied by $0$ = $0$  hence $$0! = 0\cdot 0 = 0$$ hence $$1! = 1\cdot 1 = 1$$  I am confused by this help Thanks.  But then the factorial rule of $0!$ being $1$ is misleading because $0$ x emptyset = emptyset why would it be 1?


Get time difference between db time values and today's time in mysql

I want to send email before 2 hours in db time. I developed following code to get all email addresses which has time gap equals to 2 hours or less.      include('connection.php'); //get current date and time     $time = date("c");     $timestamp = strtotime($time);        $sendtime = date("Y-m-d H:i:s", $timestamp);       echo $sendtime;   $sql = "SELECT  email FROM confirmed_user WHERE 7200>=TIME_TO_SEC(TIMEDIFF(sendTime, '$sendtime')) diff";     // $sql = "SELECT sendTime FROM confirmed_user WHERE sendTime='$timestamp'";  $result = $conn->query($sql);  if ($result->num_rows > 0) {     // output data of each row     while($row = $result->fetch_assoc()) {     echo "Email: " . $row["email"]. "<br>";     } } else {     echo "0 results"; } $conn->close();     So I think my sql query is wrong. I got following error.       Trying to get property of non-object and 'o results'.    I keep date time values as date time format in db(  2016-05-11 12:00:00 ) in sendTime field. Any suggestions?


Consider a continuous function $f$ over an interval $[a,b]$. Let $S$ be the set of all values that $f(x)$ takes over $I$. Intuitively speaking, I believe this set has a maximal and minimal value. Is this the case? How can I prove it?


Why does A New Memory Card Needs to be Formatted Before Use?

Why does a new memory card or flash drive need to be formatted before using it?  All of I get from internet is just a tip to format it before use.  But they don't explain why we need to format it first.


Solve $x\equiv 1\pmod2$, $x\equiv 2\pmod3$, $x\equiv 3\pmod4$, $x\equiv 4\pmod5$, $x\equiv 5\pmod6$ and $x\equiv 0\pmod7$

$$\begin{align*} x&\equiv 1\pmod2\\ x&\equiv 2\pmod3\\ x&\equiv 3\pmod4\\ x& \equiv 4\pmod5\\ x&\equiv 5\pmod6\\ x&\equiv 0\pmod7\\ \end{align*}$$  So the solution says we can eliminate $x\equiv 5(\bmod6)$ because the first two cases cover it, but I don't really know how it does. How do we solve it in cases like this where the moduli are not mutually relatively prime.


Community Wiki punishes users for improving their posts

Posts enter community wiki mode when... the post has been edited ten   (10) times by the original owner. -    Good users occasionally edit their posts to add new info, correct bad info, update the status, fix typos, etc. Many users make legit edits for legit reasons and end up getting their post locked into Community Wiki, ensuring they do no receive reputation for their improved post. A high edit count is more indicative of a user's editing habits than it is of the quality of the post. Can anything be changed to prevent the system from punishing users for improving their posts? Is there a better way to prevent gaming the system by edit-bumping posts?     Voting on a community wiki post (up or down) does not affect any   user's reputation.  -    This post is similar to , but there are a couple reasons this should not be closed as duplicate:   That question was from 2009, and can be considered localized in time Many upvotes were received since that was declined (now +60), begging the issue be reconsidered The problem hasn't been fixed!


Are 'ages' and 'aged' acceptable in those sentences?

I teach children aged 10 to 14. I teach children ages 10 to 14.


I am going to use Chi-squre test to see if two categorical variable are independent or not and I just realized the number of observation can affect the result of test:  Data set 1:      Group 1      Group 2 A    10              20 B    30              40   Date Set2:      Group 1      Group 2 A    100              200 B    300              400   The result of test for the second data set is 10 times bigger than the first data set and it affect the result rejecting/accepting null hypothesis.  As the ration of groups in both data set are the same it does not make sens to me to get two different result...Could you please help me to understand what sort of data I nee to use for chi test?  Thanks, Amir


Whats stopping C# compiler from implementing 'Switch' statement on 'Type'?

I understand that C# compiler as it stands does not let switching on Type like  switch (typeof(MyObj))     case Type1:     case Type2:     case Type3:   There are solutions where a Dictionary of Type and Action could be used or a static class (), but I am just curious, why is this a bad practice or not implemented in the compiler yet ?  Thank you in advance.


Can someone reset my iPad without knowing the PIN or having the "Find My iPhone" account access?

Just a hypothetical question. I'm using an iPad Air with a PIN to unlock it and a Find My iPhone set up on it. If I lost it, can someone simply reset it and start using it like if it was a new iPad without knowing the PIN or having access to my iCloud account?  PS. I see , as well as many posts on this site, claiming that if put the iPad in the DFU-Mode it can be reset. So what's the point of setting up the Find My iPhone feature then?


Setting a single value in Python nested list makes the whole row changed


I apologize if this has already been covered in some other posts, but I couldn't find it anywhere and I'm not even sure if "brace diagram" is the correct name in English.  I have found some examples of probability trees, and some others that are close (like this: ), but while playing with them I couldn't get the correct output (The part of the first "text here" when out of boundaries into the brace).  What I'm trying to do is something like this with TikZ:    I know there are some ways to do this with mathmode, but I'm really interested in learning a little more about TikZ and how it works for diagrams like this.


How to evaluate $\int\int_SF.dS$ where $F=(xz,yz,x^2+y^2)$?

Evaluate $\int\int_SF.dS$ where $F=(xz,yz,x^2+y^2)$  Where $S$ is the closed surface obtained from the surfaces $x^2+y^2\leq 4,z=2,x^2+y^2\leq 16,z=0$ on the top and the bottom and $z=4-\sqrt{x^2+y^2}$ on the side.  How we can solve such integrals?I need your help.  Without using the Gauss Divergence theorem.


Why is it not possible to visualise a 4th dimension object?

By drawing a cube on a paper or by seeing it on a screen (a 2D surface - see Figure below), we can sort of visualise how a 3D cube would look like.     I was wondering whether we will be able to visualise the tessaract (4D cube) if we build a 3D model of it? However, if we are able to, it will contradict the common belief that one (as a 3D organism) cannot visualise the 4th Dimension. This leads to the question below.      Question: What is the fundamental difference between seeing the 4th dimensions in 3-dimensions and seeing the 3rd dimension in 2D view that stops us from being able to extend our understanding of the 3D to 4D?    Well, some thoughts so far is that to visualize depth in 3D, we use light/shading (for example a 3D object looks lighter nearer to the edge and darker in the centre). The 4th dimension is time/duration, so a question would whether we can make use of time (e.g. moving the object through time???) to help us visualise the 4th dimension better??? If so, how and if not, why not?


Had J.K. Rowling planned Snape's storyline when she started writing the first book?

Had J. K. Rowling already planned all along the surprise storyline revealed in Deathly Hallows that Snape      is secretly in love of with Lily?   In my opinion this is probably true from the fifth book on, because, reading through the lines, I always thought that Dumbledore's trust toward Snape based itself on the knowledge of this secret. Is this true? Can this be extended to the other books?


Relation between confidence interval and testing statistical hypothesis for t-test

It is well known that confidence intervals and testing statistical hypothesis are strongly related. My questions is focused on comparison of means for two groups based on a numerical variable. Let's assume that such hypothesis is tested using t-test. On the other side, one can compute confidence intervals for means of both groups. Is there any relation between overlapping of confidence intervals and the rejection of the null hypothesis that means are equal (in favor of the alternative that means differ - two-sided test)? For example, a test could reject the null hypothesis iff the confidence intervals do not overlap.


Can you attack with a Loading and different weapon in the same turn?

If a creature has Multiattack (or Extra Attack), can they fire a shot from a weapon with the Loading property (such as a crossbow) and then still get an attack with a different weapon, such as a melee attack?


Numbers that can be expressed as the sum of two cubes in exactly two different ways

It seems known that there are infinitely many numbers that can be expressed as a sum of two positive cubes in at least two different ways (per the answer to this post: ).  We know that  $$1729 = 10^3+9^3 = 12^3 + 1^3,$$  and I am wondering if there are infinitely many numbers like this that can be expressed as the sum of two positive cubes in exactly two ways?  In fact, are there even any other such numbers?  EDIT: As provided by MJD in the comments section, here are other examples: $$4104 = 2^3+16^3 = 9^3+15^3,$$ $$13832 = 20^3+18^3=24^3+2^3,$$ $$20683 = 10^3 +27^3 = 19^3 +24^3.$$


Should I clean my camera sensor, or take it to a professional?

Possible Duplicate:          Can anyone offer me advice on how to clean my camera's sensor?   Should I do this myself, or take the camera to a professional? Is it precarious, or easy with the right amount of care?   I have a Nikon D3000 that has a small dot off-center of the sensor. I believe it is dirt, and I would like to remove it. I'm tempted to use a cotton-bud, but I'm afraid that I might damage the sensor.  The dot appeared after a trip to a tropical area where the camera became wet. I took the lens off and a lot of moisture, and possibly some dirt, went into the camera. The lens became fogged-up.  When I returned from my trip I ran a hair dryer for (air only, without heat) 10 minutes through the battery compartment, believing this would circulate around and dry the camera. Consequently, I noticed many speckled dots around the sensor. I also believe there's a subtle but persistent haze when I look through the lens, but I could be wrong.  It's worth noting that the photos are fine, with no evidence of distortion or blurring. The camera is now dry and it's been months since this happened. But the dot on the sensor has been there since, like an itch I can't rub.


From other's conversation,I found out they mentioned I was and sometimes they also mentioned I were. Is there any rules for I was/were?


Random Explanatory / Independent Variables

Are explanatory variables in regression always considered non-stochastic? If the explanatory variables are random or stochastic will the regression be still valid? What are the implications on the coefficients or issues with hypothesis testing one would face ?


My partitions are not shown since I installed Ubuntu 14.04

I had Windows 8.1 installed in my system and I had 3 partitions in it.  I installed Ubuntu 14.4 with the Replace Windows 8.1 option.  After installing Ubuntu I had only one partition.  Have all my partitions been erased? If so how can I recover my data?


Index Exists, data is present, but statistics are empty. Why?

I’ve created a dump of all statistics on all tables in a Production database (based on the three sets returned by DBCC SHOW_STATISTICS). The database has been up and running for several months, and is actively used around the clock.  Reviewing it all, I find that several statistics are not actually set. That is, the statistics entry is there, but “LastUpdated” is null, and there are no steps in the histogram table. I am not able to find a consistent reason for this—some are for indexes, unique indexes, filtered, indexes, filtered unique indexes, and auto-generated stats.  Why is this? I can see a handful of remotely possibly reasons. Many are for where there is no data in the table (this makes sense), but there are many that do have rows (up to 10s of millions), and for any reason that might barely explain it ( “first-column duplicates” of other stats/indexes, unique indexes, filtered indexes, unlikely datatypes such as bit or large nvarchars), I can find something similar in another table/index where statistics are present.  I’m mostly convinced it’s not just one single thing. What are the possible reasons that statistics might not be present for tables under these conditions? How worried should I be about this?


Syntax Error: unexpected end of file -- Bash script

I am trying to create an spritz app! Everything was working fine, but since yesterday I keep getting this error: ./spritz: line 176: syntax error: unexpected end of file  I have checked the script file and everything seems perfect! I am confused I have an if statement at last and it looks correct! Here is the last portion:      #checks if speed is 150 157 if [[ $2 -eq 150 ]]; 158 then 159 starttime=$SECONDS 160      FS=$'\n' 161      for j in `grep --color=always -iP '\b[^aeiou\s]*[aeiou][^aeiou\s]*\K[aeiou]' $1`; 162      do 163            #Reads the text file in the centre of the screen 164            echo "                                                    ___________________" 165            echo "                                                             $j"; 166            echo "                                                    ___________________" 167            echo "                                                                               Speed 150 wpm" 168            sleep  0.9; 169            clear; 170       done 171 endtime=$(($SECONDS - $starttime)) 172            echo "You read $words_read words in $endtime seconds!" 173       exit 8 174 fi


I have given this code for intersection: function intersectPolyByPolyFC(poly,fcPoly){         var fgp=[];//variable for feature group         var bbPoly=turf.bboxPolygon(turf.bbox(poly));//polygon representation of the bounding box of a reference polygon         for(var i=0;i<fcPoly.features.length;i++){//loop through the feature collection of polygons             var bb=turf.bboxPolygon(turf.bbox(fcPoly.features[i]));//variable bb represents each polygon for feature collection             if(turf.intersect(bbPoly,bb)){//condition to check if the two bounding boxes intersect                 var int= turf.intersect(poly,fcPoly.features[i]);                 if(int){                     int.properties=fcPoly.features[i].properties;                     fgp.push(int);                 }             }         }         return turf.featureCollection(fgp);     }  and the function definition I have given as var bufline=turf.buffer(line,0.05,{units:"kilometers"}); var intBUOWL= intersectPolyByPolyFC(bufline, lyrBUOWL.toGeoJSON()); L.geoJSON(intBUOWL,{style:{color:'red',weight:5}}).addTo(mymap);  When I am drawing a line over a polygon for intersection I am getting this error Uncaught TypeError: Cannot read property 'map' of undefined     at Object.t.collect (turf.min.js:1)     at summarizePointsByLine (buffer.html:440)     at NewClass.<anonymous> (buffer.html:155)     at NewClass.fire (Events.js:190)     at NewClass._fireCreatedEvent (leaflet.draw.js:8)     at NewClass._fireCreatedEvent (leaflet.draw.js:8)     at NewClass.completeShape (leaflet.draw.js:8)     at HTMLAnchorElement.handler (DomEvent.js:92)  How can I resolve this error?


Is it okay to have a multi-language deck?

I want to buy a few booster pack from a local shop that only gets them in French. Is it generally acceptable to show up to a tournament with cards in different languages?


How can I download a website and the links it references, but nothing more?

I have a list of links here:   That I would liked all downloaded. Would anyone know how this would go?


How could Narcissa Malfoy trust Harry and take his word for it that Draco is alive?

Narcissa  (mother of Draco) is asked to check whether Harry is alive after he has been "killed". At this point Narcissa asks whether her son is alive. How could she trust Harry and believe him? Notwithstanding that she considered Harry to be her 'enemy'. Harry could've have lied and said Draco was alive (if Draco was dead). In this case, Harry gets the benefit (as he escapes by being declared dead), while Narcissa is given the false hope that her son is alive. What matters isn't whether Draco is dead or alive, Harry could simply get away by saying yes. So why did Narcissa trust Harry and take his word that Draco was alive?


javascript function scoping "it prints hello instead of undefined"

var sagas = [];     var newfunction = function () {         var saga = 'hello';         sagas.push(function () {             var deed = 'nice man';             console.log(saga);         });     };     newfunction();     sagas[0]();     when we run sagas[0]() it prints hello it should print undefined as per function scoping ? I tried to think why it prints hello but couldn't


Product Identity Multiple Angle or $\sin(nx)=2^{n-1}\prod_{k=0}^{n-1}\sin\left(\frac{k\pi}n+x\right)$

I have run across this interesting identity that I am unable to verify.  $$\sin(nx)=2^{n-1}\prod_{k=0}^{n-1}\sin\left(\frac{k\pi}n+x\right)$$  Can anyone provide a hint as how one would prove this?   This identity was found on the Wolfram site.


How do you install Minecraft mods on a Mac?

I've seen videos for Minecraft mods which add features like oil, pipes and guns.  Where can I find these mods, and how do I install them on a Mac?


Asphalt career performance isn't synced between my PC and Android phone

I am playing asphalt 8 airbone on my pc which runs on windows 8.1 pro and on my android smartphone. I connected Asphalt 8 with my same facebook account but it doesn't show same career performance, my car pack, etc. Help me out with this.


How to recover photos from an iPhone 3G?

I used an iPhone 3G from May of 2009 until around the spring of 2013, at which time I upgraded to the iPhone 5. I've always been a prolific iPhotographer :) and recently pulled around 12,000 photos off my iPhone 5 for backup and to free up disk space. I've kept the old iPhone 3G, though, and suspect it has thousands of pictures on it that need to be removed from the phone and backed up on my cloud, my laptop, and an external hard drive. However, Apple no longer makes available the OSX that supports and grants access to an iPhone 3G through iTunes. I can't hook it up to my laptop (Dell XPS 15Z, if it helps to know what I'm running, with Windows 7) and access the pictures to manually move them off the phone.  How do I recover pictures from an iPhone 3G? Is there anything that can be done?  Is there anything that can be done? As it is, I can't get my computer to even see the 3G, much less charge the phone through the computer or allow me to access the phone's drives and my pics. I'm currently charging the 3G via wall plug/USB, which I think will allow me to look at my photos on the phone itself once the phone is juiced up ... but I really just want to recover and transfer my images off the iPhone 3G for safekeeping.  I did search this site prior to posting and could not find my exact question. Please don't hesitate to VTC if I've accidentally submitted a duplicate.


Where are the links of the saved pages of Opera Mini are stored in Android?

I have an Android 2.3 Gingerbread and have installed Opera Mini. I used it to save many useful pages for offline viewing and I want to save the links of the pages in a text file. So I need to find the place where the links of the saved pages are stored.


Probability mass function of the sample mean

Suppose that $X_1,X_2,\ldots,X_n$ is a random sample from a distribution with probability function:  $$p_X(x)=\begin{cases} 1/2 &x=-1,1 \\ 0 & \text{otherwise} \end{cases}$$  Now if we define the average   $\bar{X}= \frac{1}{n} \sum X_i$, I need to show that that for an odd $n$ the probability function for $\bar{X}$ is:  $$p_{\bar{X}} (x)= \frac{\binom{n}{\frac{n}{2} (x+1)}}{2^n}$$ for $x=\pm 1/n,\pm 3/n,\ldots,\pm 1$, $0$ otherwise.    Since $P[\sum X_i=k] =P [\bar{X}=k/n ]$, I thought it would be easier to first derive the probability function for the sum. Since they are still $2^n$ n-tuples and each one is equilikely, I need to count the ones whose sum is $k$ for:  $k=\pm 1,\pm 3,\ldots \pm n-2,\pm n$ (since even numbers are not a feasible combination)  The problem here though is that I do not immediately recognize how I could count all these tuples. Could you please help me with this? If it is easier to proceed another way, I am of course all ears.


Term for a word that's a different word when spelled backwards

Palindromes are words, sentences, numbers that are the same forwards and backwards. Is there a term for words that are one word forwards but a different word backwards? For example, star backwards is rats, or god is dog.


Why is the intersection of the empty set the universe?

I haven't found an answer yet that I can make complete sense of, so I'm asking again to try and clear it up if I have any misconceptions.   If one defines $\cap_{i\in I}\alpha_i = \{x:\forall i\in I, x\in\alpha_i\}$ then apparently if $I = \emptyset$ this definition yields the absolute universe. This is just stated as if it is clear why, though I cannot see why. If $i\notin I \forall i$ then there is no set $\alpha_i$ for any $x$ to be a member of...?  I know I must be misreading this, but I can't see how by so much...  Edit: Let this intersection be $Z$, for convenience.


Why is there no official Stack Overflow Android app?

I was looking at  trying to find and official Stack Overflow app for an Android smartphone. Is there any reason why SO doesn't have any?


How many syllables are there in the word "fire"?

We were making up Haiku, and there was some disagreement about the number of syllables in "fire."  Now granted Haiku isn't technically about syllables (see ), so technically it was a meaningless discussion.    However, I still do not know how many syllables are in "fire."  I understand an  might be at play.


I know i can create an instance of a Type Paramter using the method given . But why doesnt  the following statement compile?  public static <E> void append(List<E> list) {     E elem = new E();  // compile-time error     list.add(elem); }  List<String>list=new ArrayList<String>(); append(list);   1.Cant the type of E be detected based on what i pass in the method append()? Then what is Type Inference used for? 2. Even if Type Inference is not applied, then wont E elem=new E() will b converted into Object elem=new Object() at run time, which should be fine? In any case, it should work. But why it doesnt?  EDIT: The duplicate qeustion that they have given link to only answers the methods by which we can create an instance of Type Parameter. It doesnt answer why this method wont work.


random nullpointerexception on bufferedreader?

I've been making a game and when it came to making the code much less messy i came across a null-pointer so i gave up and held Ctrl+z (undo) for a bit until it stopped. The code was back to normal but when i ran it, it comes up with the same null-pointer to do with a class that i didn't change what so ever. The null-pointer is as follows:  Starting programm... Exception in thread "main" java.lang.NullPointerException     at java.io.Reader.<init>(Unknown Source)     at java.io.InputStreamReader.<init>(Unknown Source)     at game.shaders.ShaderProgram.loadShader(ShaderProgram.java:98)     at game.shaders.ShaderProgram.<init>(ShaderProgram.java:25)     at game.shaders.StaticShader.<init>(StaticShader.java:34)     at game.renderEngine.MasterRenderer.<init>(MasterRenderer.java:32)     at game.engineTester.MainLoop.main(MainLoop.java:57)   The ShaderProgram seems to be causing the problem at line 98 were a bufferedreader is created and defined. The ShaderProgram lines that causes the error is as follows:          try{             InputStream in = Class.class.getResourceAsStream(file);             BufferedReader reader = new BufferedReader(new InputStreamReader(in)); // line 98, has nullpointer ???             String line;             while((line = reader.readLine())!=null){                 shaderSource.append(line).append("\n");             }             reader.close();         }catch(IOException e){             e.printStackTrace();             System.exit(-1);         }   i am using lwjgl for this the source for this DOES exist even though some people are complaining that it isnt. it is within the shaders package and it is vertexShader.txt and fragmentShader.txt


I can not install any application due to a repository update error

When I run sudo apt-get update, I receive this error message:    W: The repository 'http://ppa.launchpad.net/ubuntu-wine/ppa/ubuntu yakkety Release' does not have a Release file.   N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.   N: See apt-secure(8) manpage for repository creation and user configuration details.   E: Failed to fetch http://ppa.launchpad.net/ubuntu-wine/ppa/ubuntu/dists/yakkety/main/binary-amd64/Packages  404  Not Found   E: Some index files failed to download. They have been ignored, or old ones used instead.     Due to this error I can not install any application, please help me in detail, I am very new to Linux.


How would I find the sum below?    $$ \sum_{k=0}^{n} {\frac{1}{k+1} {n \choose k}}=?$$  I need help starting on the problem. Would I first need to utilize the Binomial Theorem proof to get started on it?    Thank you.


Two Definitions of the Special Orthogonal Lie Algebra

I am encountering two definitions of the special orthogonal lie algebra, and I would like to know if they are equivalent, and if there are advantages to working with one over the other.  If we begin with an $n$-dimensional vector space $V$ over a field $k$ and a chosen basis, we can define a bilinear form on $V$ by a matrix $S\in M_n(k)$, ie, let $\langle v,w\rangle=v^tSw$ for all $v,w\in V$.  Now $g\in GL_n(k)$ preserves the form ($\langle g(v),g(w)\rangle=\langle v,w\rangle$) if and only if $g^tSg=S$, so all such $g$ form a linear algebraic group $G$.  The tangent space at the identity of $G$ will be contained in that of $GL_n(k)$, so $T_eG\subset T_eGL_n(k)=M_n(k)$, and in fact, $T_eG=\{B\in M_n(k)\mid B^tS+SB=0\}$.  $T_eG$ becomes a lie algebra, $Lie(G)$, if we define the bracket to be the commutator of two matrices.  Now, if $S=I_n$, it follows that $G=O_n(k)$ is the orthogonal group of matrices satisfying $g^tg=I_n$, and $Lie(G)=\mathfrak{so}_n$ is the lie algebra of antisymmetric matrices.  In Humphrey's Introduction to Lie Algebras and Representation Theory, he defines $\mathfrak{so}_n$ to be all matrices $B$ satisyfing $B^tS+SB=0$, where $$ S=\begin{pmatrix} 1&0&0\\ 0&O&I_l\\ 0&I_l&O \end{pmatrix} \hspace{.5in}\text{or}\hspace{.5in} S=\begin{pmatrix} O&I_l\\ I_l&O \end{pmatrix} $$ depending on the parity of $n$.  The matrices obtained in this way are not antisymmetric, nor is the group $G$ preserving the form defined by $S$ the orthogonal group $O_n(k)$.  Are the two groups obtained from considering different $S$ isomorphic?  Are the two lie algebras isomorphic?  If so, why would one prefer one form to the other?


How to solve for $y$ the equation $x= y^y$?

I need an equation where I receive a number that when raised to itself equals the input.  Formally: in $x=y^y$ solve for $y$.  Intro to Calculus level knowledge. If the Lambert function is necessary, please explain it to me.


I am trying to wrap text around a figure, but I would like this figure to be centered in the middle of the page. I have been using the wrapfig package. My code is below. \begin{wrapfigure}{r}{0.5\textwidth}   \centering     \includegraphics[width=0.7\textwidth]{AvgReLease.png}   \caption{AvgReLease}  \end{wrapfigure}  My code aligns the image to the right. Is it possible to align the image in the centre of the page instead, such that it separates two bodies of text (say, in between paragraphs)? I have also tried to use the code below, \begin{wrapfigure}{R}{0.5\textwidth} \textbf{\begin{figure}[htp]     \centering     \includegraphics[width=10cm]{AvgReLease.png}     \caption{Average Re-Lease (days) vs Storage Type}     \label{fig: Average Re-Lease vs Storage Type} \end{figure}} \end{wrapfigure}  but the image appears on a different page.


I have a difficulty with understanding following example:  We have $N$ balls amongs them there are $b$ white colored. We take from them $n$ balls(we take them without replecments). Let $X$ be a number of white balls we get. Calculate $EX$. Now lets have $X=\sum^{N} X_i$ where $X_i$ is $1$ if we get white ball in $i-th$   sampling and $0$ otherwise. Then we calculte $E X_i=P(X_i=1)=\frac{b}{N}$ And so $E X=\frac{n\cdot b}{N}$. I can agree that if we take one ball probability will be indeed $\frac{b}{N}$, but if we take another there will be one ball less, intuitively that should affect probability.


How to find the fundamental period of the product of two periodic functions?

Say you wanted to find the period of $x(t)=\sin(at)\sin(bt)$ where $a$ and $b$ are real constants. How could you go about this?


Good references for 'predictive models'?

I am a recent graduate working as a Data Scientist and I often get lost in 'choosing' which model/models to use for a predictive task. Just recently I was trying to build a prediction on time-series and the number of different models/methods available such as ARIMA, SARIMA, ARIMAX etc is pretty large. Not only that, but even though I can read more about them and have an 'educated guess' at which one to use; I still do not know the assumptions behind the models and whether they are suitable for a task at all. It is like a try and see if it works method. So I am looking for some books/reference mostly concerned with traditional statistical inference models I can dive deep into and learn as much as I can about it. (I have a background in Mathematics and Statistics) Thank you


How do I label different rows or columns of a matrix using braces?

I have a matrix enclosed in brackets [ ] (or (), or {}, or |'s, or ||'s):   - a b c d - | e f g h | | i j k l | - m n o p -   which I want to label like so:             R          |---|   -- - a b c d -  A|  | e f g h |   -- | i j k l |      - m n o p -     Where the dashes by the labels are meant to be giant {'s as in this picture:  How can I do this?    Although two answers have been provided that work to an extent, I've added a bounty because I'd like to see if anyone has, or can come up with, a neat, robust solution.


Why do we use "the" followed by "user" in "a window prompts the user to make..."?

I've found this piece of text in the Android Developers Documentation:     A dialog is a small window that prompts the user to make a decision or enter additional information. A dialog does not fill the screen and is normally used for modal events that require users to take an action before they can proceed.   Please explain why they use 'the' followed by 'user', even though they don't talk about a specific user or 'the user as a class'.


I may be dense here, but here is my problem. I am writing an android app that is supposed to manage an inventory of items.  There are multiple Spinner and AutoCompleteTextView objects on one of my layouts that I am trying to populate from one function, instead of having one function for each.  Here is what I have... The object _type is supposed to become a reference to the class for the Sqlite query to populate data in. I used Object in this sample code, but I have run it, as var, object, type...  I have several issues coming up here,  1) I get '_table' is a variable but is used like a type 2) I am getting a similar problem with _res when I start trying to parse the data returned from the db connection  In essence what I want to do is use a variable as a place holder for a type.  I've tried using a number of casts, and functions like .GetType(), but they still throw the same "x is a variable but used like a type". When I use it in the context of the list that receives the data I get the message "list requires one type argument"  At the moment I have this working by just having independent functions for each form item I am working with, but that's chunky, and I'd love to extend this to work on all form items that get data from the DB.        public ArrayAdapter<string> PopulateAdapter(Context _c,                                                  MyDatabase.enTables _which,                                                 MyDatabase.Options _o =null)             {                 string[] _l;                 SQLiteConnection db = new SQLiteConnection(MyDatabase.GetDBFilePath());                 string _sql;                  Object _table;                 List<_table> _res;                  switch (_which)                 {                     case GMDatabase.enTables.Manufacturers:                         _sql = "SELECT * FROM Manufacturers";                         _table = MyDatabase.Manufacturer;                         break;                     case GMDatabase.enTables.Styles:                         _sql = "SELECT * FROM Styles";                         _table = MyDatabase.Styles;                         break;                  }                  _res<_table> = new List<_table>;                 _res = db.Query<_table>(_sql);                 if (_res.Count)                 {                     for (int i = 0; i < size; i++)                     {                         _l[i + 1] = _res[i].Name;                     }                     return new ArrayAdapter<string>(this, Android.Resource.Layout.SimpleSpinnerDropDownItem, _l);                 }                 return null;             }   Thank you for taking a look, and any advice or ideas would be most appreciated!


I'm trying to write a two sided permutation test to test the alternative hypothesis there is a difference in the medians of 2 independent samples. My question is this: am I calculating the p-value correctly? Thanks SO much!  sample1 <- groundwater$West[!is.na(groundwater$West)] sample2 <- groundwater$East ts <- median(sample1) - median(sample2) > ts [1] 0.105 R <- 9999 all <- c(sample1, sample2) k <- 1:length(all) reps <- numeric(R) for (i in 1:R) {     m <- sample(k, size=length(sample1), replace=FALSE)     permsample1 <- all[m]     permsample2 <- all[-m]     reps[i] <- median(permsample1) - median(permsample2) } pvalue <- sum(c(ts, reps) <= ts)/9999 > pvalue [1] 0.9223922


Singular or plural verb form where subject includes a "parenthetical" element

My question arises from , where OP asks whether he should use the singular or plural verb form after "the title, as well as the tone,"  As luck would have it, when I searched Google Books for , I found...        ...and...        At the risk of having this question closed as just peeving, I feel that the first one should have been plural "err", because without the commas it seems to me both "the title" and "the tone" have more or less equal status as "joint" subjects of the verb, making it plural.  On the other hand, I feel the commas in the second example effectively demote "the tone" to "parenthetical" status (the clause is almost incidental). Since this encourages us think of "the title" as the primary subject, it should have been singular "derives".  I'm no great fan of "grammatical rules", but it seems weird to me that the only two relevant examples for this specific wording should both (in opposite ways!) contradict my inclinations.  What's going on?


How many times was Picard's mind taken over?

I can think of at least three episodes of Star Trek: The Next Generation in which Picard's mind was taken over, or at least intentionally messed with in order to make him do specific things.   By an energy being in  By Bok, using a "thought maker" in  By the Borg, by assimilating him in    Are there more examples of Picard's mind being taken over?


Decrypt files after Petya ransomware attack in 2017

Does anybody know if the recent flavour of  (active in June 2017) is somewhat different from one that appeared back in 2016?  I am only interested in the decrypting approach.  This was asked back . But I can't find any info on how relevant that solution is to the recent case.  Thank you.


How do I tell the concepts of subclass function implementation, @Override annotation and "overloading" functions apart?

I have an abstract class like so:  abstract class Player {          //some stuff          public abstract String getName();      }   and in one of the subclasses I am implementing (and overloading / overriding as well? Here is where I am not sure) the function getName() like so by typing out the whole function again:  public String getName(){     return "John"; }   but I can also in my subclass simply write "getName()", press enter and my IDE automatically fills out the following code for me, which also works (if I change null to "John" in this case):  @Override public String getName(){     return null; }   Obviously since it states "Override" I am here overriding the function in the abstract superclass. But am I not already overriding the function even without putting "@Override" above the function?   What I am saying is: I have an abstract function, so it is only implemented in a subclass and not in the superclass itself. Doesn't this mean that by implementing it I am automatically overriding it as well, since it has no implementation in the superclass to begin with? Why should I write @Override then? Or am I just "overloading" if I don't put "@Override" in there?


Are there any open-source simple network monitoring applications?

I am debugging a problem with one of our systems. Every Sunday, it stops communicating with another server. If we reboot both servers, communication works again.   I was wondering if there are any small footprint apps that monitor TCP port availability and network connectivity, possibly logging any downtime. I'd also like it to be open source if possible, but if there is another solution that is proprietary, I'd like to hear about it also.


Why is the determinant of a rotation matrix equal to 1? I would like a geometric interpretation of this. Just curious.


Failure of isomorphisms on stalks to arise from an isomorphism of sheaves

It is well-known (Hartshorne 2.1.1) that if $F$ and $G$ are sheaves on a space $X$, then $\phi:F\rightarrow G$ is an isomorphism if and only if the induced stalk map $\phi_p:F_p\rightarrow G_p$ is an isomorphism for all $p\in X$. However, if we have a collection of isomorphisms $\{\psi_p:F_p\rightarrow G_p\}_{p\in X}$, this does not guarantee that $F$ and $G$ are isomorphic, because the $\psi_p$ might not be related to each other, i.e. there might not be a sheaf map $\psi:F\rightarrow G$ such that $\psi_p$ is the induced stalk map for all $p\in X$.  However, I was recently making this point to someone and was unable to think of a good example of non-isomorphic $F$ and $G$ having isomorphisms $\psi_p:F_p\rightarrow G_p$. I'm sure I knew one at some point, but I'm blanking on it now. Can someone provide an illustrative example, e.g. an example that occurs in some natural or basic problem, or one that captures the essential pattern of any example where this issue arises, or one where it is clear that $F$ and $G$ could not be isomorphic?


What category does the 'the recent perfect' belong to?

A scholar has said that there are 4 usages of the present past tense:   The Universal sense of the Perfect, used to indicate that a state of affairs prevailed throughout some interval stretching from the past into the present       I've known Max since 1960.  The Existential sense of the Perfect, used to indicate the existence of past events     I have read Principial Mathematica five times.  The Stative/Resultative sense of the Perfect, used to indicate that the direct effect of a past event still continues     I can't come to your party tonight - I've caught the flu.  The Hot News sense of the Perfect, used to report hot news     Malcolm X has just been assassinated.    To what category does the recent past belong?


How to make a Generic library closed source?

Why cannot a C++ library with Generics (ie. templates) be closed source ?  Suppose I want to make an object file for my library and provide only the implementation and the header file, what should i do ?  I understand that at the time of linking the compiler will be confused about the data type and hence this is not possible.   So isn't there any work-around that C++ provides for people who don't want to make their libraries open-source ?  How do other languages(Java) manage this ?


If I have a simple List< Point2D > declared.  Example:  List<Point2D> listOfPoints;  /* What I tried */ Point2D point1; listOfPoints.add(point1);   But, how does one initialize point1 so that I can have a coordinate of let's say (3,2)?


how to show that $a_{n+1}=\sqrt{6+a_{n}}$ is bounded?

I have to show that the sequrnce $\{a_n\}$ with $a_{n+1}=\sqrt{6+a_{n}}$ is bounded, i know : $a_{n-1}<a_{n}$ because i demonstrated this. I tied to use this relation: $ab\leq \frac{a^2}{2}+\frac{b^2}{2}$. I don't kow how to increase $\sqrt{6+a_{n}}$


Change swedish appendix title 'bilaga' to 'appendix'

I'm writing a document in Swedish, and appendices are then called 'bilaga' which is a translation of 'appendix' not widely used in my field. Hence, I'd like the title in appendix A to read 'Appendix A' and not 'Bilaga A'. I've tried using \renewcommand\appendixname{Appendix} but it changes nothing. The toc is fine as it is - doesn't use the word Appendix or Bilaga at all, just A, B and so on.  EDIT: Don't know what a MWE is, but here are pieces of my latex code that I think may be relevant:  \documentclass[a4paper,11pt,fleqn,twoside,openright]{report} \usepackage[swedish]{babel} %...{lots of other stuff related to figures and page layout} \usepackage{appendix}  \renewcommand\appendixname{Appendix}  \begin{document}  \chapter{oneone}  bla1 bla1  \chapter{twotwo}  bla  \appendix \chapter{titel first appendix}  appendix text  \end{document}


Define $S_n=f(S_{n-1})$ for $n\geq 1$. Prove $S_n$ is a convergent sequence.

Let $f$ be differentiable on $\mathbb R$ with $a=\sup \{|f'(x)| :x\in \mathbb R\}<1$ Select $S_0\in \mathbb R$ and define $S_n=f(S_{n-1})$ for $n \geq 1.$ Prove that $\{S_n\}$ is a convergent sequence.  My attempt  I know that I might have to show that $S_n$ is cauchy since it's convergent. By definition $S_n$ is cauchy if there exists a natural number $N$ such that $m,n>N$ implies $|X_m - X_n| < \epsilon$.  I was given a hint that we have to use the IVT to show that it is cauchy. The professor wrote on the board:  By IVT,  $$|S_{n+1}-S_n|=|f(S_n)-f(S_{n-1})|$$  I understand this step but I don't understand the next few steps  $$ = f'(c)|S_n - S_{n-1}|<a|S_n-S_{n-1}| \\ < a^2 |S_{n-1}-S_{n-2}| \\ a^n|S_1 - S_0|$$


I want to check whether the sum of two list is same or not.   lst1 = [1 2 3 4] lst2 = [0 3 3 4] if sum(lst1) == sum(lst2):     return true   Here the sum returns true. If I hash the list I get different values but hashing is computationally expensive. I only want to check whether the elements in the two lists are same (only with the exception of 1 element). I am using Binary search technique of dividing the list and then checking the hash. if hashes are different I am checking if its more than once.  But as I said hashing is computationally expensive. Also the order does matter here. Thank you


Rounding raster pixel values to one decimal place in QGIS

I have single band raster whose values somehow were set to something like 1.399999999 instead of 1.4, 1.29999999999 instead of 1.3 (I'm not sure about the number of 9's there.), 1.2000047683 instead of 1.2. While some pixels do have a value 0.5. I actually need all values to one decimal place like0.5, 1.2, 1.3, 1.4. For this I searched around and bumped into . I did not find gdal.calc as suggested but found r.mapcalculator (dialog box looked similar). I then used the function round(A,1). But it did not work.   How can I round the pixel values to one decimal place ?  When I used raster calculator raster@1 * 100 the new raster formed has values like 50, 120, 130, 140 and then again used newraster@1 / 100 to obtain 0.5, 1.20000047683, 1.299999999, 1.399999999.


Pattern and Matcher in Java: Matcher only finds one match instead of two

I'm working with Pattern and Matcher in Java. I have the following code:  String searchString = "0,00,0"; String searchInText = "0,00,00,0" Pattern p = Pattern.compile(searchString); Matcher m = p.matcher(searchString); while(m.find){   ...  }   My Problem is that the Matcher only finds one match from the first zero to the 4th zero. But there should be another match from the 3rd zero to the last zero.   Can someone help me? Is there a workaround?


How to use files selected in nautilus as arguments to a script

I wrote MyScript.sh! MyScript.sh works great from the command line; it takes one or more file paths as its arguments.  In Ubuntu 18.10 how can I:   After selecting one or more files in Nautilus/Files. Trigger MyScript.sh using the selected file/files as arguments?   I am happy to use either a contextual menu (i.e. right click), or a keyboard shortcut (.e. through Settings > Keyboard > Custom Shortcuts).  Unacceptable answer: I am not looking for someone to tell me to type ./MyScript.sh in the command in a terminal, and then drag-and-drop a file/files onto it from nautilus followed by <ENTER>.  Edit 1: I have tried placing MyScript.sh in ~/.local/share/nautilus/scripts/, ensuring it is executable, and right clicking on a file to apply, but no Script submenu appears.  Edit 2: I have set a Keyboard Shortcut in Settings > Keyboard, but the script does not execute.


Question about writing a proof with continuous functions

How would I write a proof for this example?  We know that all polynomial functions on the reals are continuous by using the sequential definition of continuity. In particular, we know that the function $f: \mathbb{R} \rightarrow \mathbb{R}$ given by $f(x) = x^2$ is continuous. Prove this using the $\epsilon$-$\delta$ definition.


I am trying to configure mod_wsgi to use Python 2.7.  I downloaded and unpacked the source and ran  ./configure --with-python=/usr/local/bin/python2.7   After this mod_wsgi.so-2.4 and mod_wsgi.so-2.5 appeared in /usr/lib/apache2/modules.  I restarted the server but this reports "internal server error".  Error logs show that on start-up the server is reporting usage of Python 2.5.2 -- the same version as previously.  How do I get Apache to run Python 2.7? How do I get mod_wsgi configured properly to run with Python 2.7?


How can I get Emacs to correctly place auto-saves and backups outside of my source tree?

Emacs creates backup files (which I want it to do) but it puts them in my source tree (which I do not want it to do). Following instructions elsewhere, I've placed the following in my .emacs file:      ;; Disable auto save                                                                                (setq auto-save-default nil)      ;; Save all tempfiles in $TMPDIR/emacs$UID/                                                                                (defconst emacs-tmp-dir (format "%s/%s%s/" temporary-file-directory "emacs" (user-uid)))    (setq backup-directory-alist          `((".*" . ,emacs-tmp-dir)))   It seems to be ignoring these directives and merrily continues to create the autosave files in the source directories. Any ideas?


Is it safe to travel to Miami Beach shortly after hurricane Irma?

Two months ago my girl and I booked our vacation. We are from Berlin, Germany and wanted to see the U.S. Our first stop is Miami Beach at the 15th and we want to stay there for 3 days and continue to NYC. Later on we will go to Vegas and come back to Miami the 26th of September and stay there another 4 nights.  I expect the hurricane will be gone by the 15th, but I have no idea whether it will be okay. For me okay means that we can reach our hotel and sleep there.  What do you suggest? I know this question is primarily opinion based, but here in Germany we don't have hurricanes and I don't know how fast the state will recover.


Highlighting Java annotations in lstlistings

Is it possible to highlight Java annotations in lstlisting?   I could not find any similar questions in tex.stackexchange. I'm searching for some yellow-like color.  Update: I found another question similar to mine, but it didn't work well. My code is:      \documentclass{report} \usepackage{xcolor} \usepackage{listings}          % for source code snippets. \definecolor{pblue}{rgb}{0.13,0.13,1} \definecolor{pgreen}{rgb}{0,0.5,0} \definecolor{pred}{rgb}{0.9,0,0} \definecolor{pgrey}{rgb}{0.46,0.45,0.48} \lstdefinestyle{Javastyle}{       showspaces=false,     showtabs=false,     breaklines=true,     showstringspaces=false,     breakatwhitespace=true,     commentstyle=\color{pgreen},     keywordstyle=\color{pblue},     stringstyle=\color{pred},     basicstyle=\ttfamily\singlespacing,     moredelim=[il][\textcolor{pgrey}]{\$\$},     moredelim=[is][\textcolor{pgrey}]{\%\%}{\%\%},     rulecolor= \color{black}  }  \begin{document}  %\lstset{style=Javastyle} \begin{lstlisting}[language=Java] @NonNull public static byte[] longToBytes(long x) { buffer.clear(); buffer.putLong(0, x); return buffer.array(); } \end{lstlisting} \end{document}   When I remove the % before \lstset{}, I get an error message:  Undefined control sequence. \begin{lstlisting}[language=Java]


Spacing changes when using unicode-math range feature. Why?

You can use the range feature of unicode-math to set the math font for a specific unicode slots or the macro accessing the glyph. I tried this with the sum sign & Latin Modern, see my example:  \documentclass{scrartcl}  \usepackage{amsmath} \usepackage{unicode-math} % use unicode in math & setup math fonts \setmathfont{Asana Math} %\setmathfont[range=\sum]{Latin Modern Math} % substitute Sum sign  \begin{document}  Notice the different sum sign $\sum$, as intended.   Notice also, the difference in spacing, not intended: \begin{equation}     \begin{bmatrix}         0           & \frac{1}{2}   & \frac{2}{3} \\         \frac{3}{4} & 0             & \frac{4}{5} \\         \frac{5}{6} & \frac{6}{7}   & 0     \end{bmatrix}     \begin{pmatrix}         A \\         B \\         C     \end{pmatrix} \end{equation} \end{document}   However, not only the sum sign, but also the spacing in the matrices changes. With Latin Modern commented out (as in the example):  With Latin Modern active (remove % before relevant line):  Why is that? BTW, I'm using Lualatex from TeXLive 2012.


Distribution of number of Bernoulli trials to a given number of successes

Suppose you have a series of n trials, where the probability of success  in each trial is p.  The distribution of the number of successful trials follows a Binomial distribution with parameters (n, p).  The mean is given by np whereas the variance is np(1-p).  So far so good: this is pretty mundane Stats 101 stuff.  But suppose now that I only knew about the successful trials, and had no knowledge of the total number n of trials, which is the variable I am interested in estimating.  For example, I knew I had 100 successful trials, where each trial had a 0.1 chance of success.  Is there a known probability distribution that describes the probable outcomes for n, the total number of trials?  Estimating the mean is easy: if m is the number of successes, then it's just m/p.  But what about variance and other measures?  What if each success had a different (but known) chance of success?  Suppose I had the following records:   success1 (with p=0.1) success2 (with p=0.1) success3 (with p=0.2)   Again, a good estimation of the total number of trials can be obtained by simply summing 1/p for each successful trial.  In this case that number  is 10+10+5=25.  But what about variance and other measures?


It looks like it's currently not possible to view the revision history of a post from the mobile site. I think it would be a lot simpler than loading the desktop site on a phone just to get the revision history.


A few months ago, I started getting these pop-ups from evolution-alarm-notify. They are some kind of calendar reminder. But they are horribly inaccurate. They either don't reflect any changes I have made to calendar events or they include all previous versions of the events and may or may not include the current version of those events. And I can't seem to mark events as complete in the evolution-alarm-notify window. I don't need these pop-ups and would prefer to just make them go away permanently. I don't have the Evolution mail app installed, and can't find an evolution-alarm-notify app on my system. So how do I get rid of evolution-alarm notify? Ubuntu 20.04.2 LTS GNOME 3.36.8 Dell Precision 7740


How do I print an image over multiple pages?

I have a very tall image (880x9445 pixels) which I would like to print (specifically, to PDF).  But when I print the image it always comes out as one page; there does not seem to be any way to scale its width to a page and thus end up with multiple pages.  I tried using the image viewer and GIMP, is there anything else that will give me this option?


Do I wait to get to the Point of Entry before I declare my interest to spend extra 3weeks on a conference visa or do I book my flight with allowance for the extra stay of 3 weeks.


1.I will study hard until I get a high score on this exam. 2.I will study hard until I've gotten a high score on this exam.  I think these sentences are grammatically correct. but if I add a specific time, I think these sentences have to be only this one:  3.I will study hard until I get a high score on this exam on July 25th.  And how about these?  a. I'd like to watch all of the holocaust movies present in the world until I've become an expert on it. b. I'd like to watch all of the holocaust movies present in the world until I become an expert on it.  Since there's no a word representing a specific time, both of them are okay, right? And what I'd like to know is the difference between "have gotten" and "get". What I know about them is we can use "future perfect" to refer to unspecific future event that might happen before some accident. but "get" refers to future event that could be either a specific scheduled event or unspecific future event. that's why if I add a specific time mentioning, I have to use "get".


Why in quantum mechanics must orthogonal states stay orthogonal?

Given two states $|A(t)\rangle$ and $|B(t)\rangle$. If $\langle A(0)|B(0)\rangle=0$ then for all $t$, $\langle A(t)|B(t)\rangle=0$.  This is a fundamental rule of quantum mechanics. And we can imply that states evolve unitary with $|A(t)\rangle = U(t)|A(0)\rangle$.  Which is equivalent(?) to saying that states evolve with linearly.  One can think of this as two arrows on a circle. And they evolve by going round the circle, keeping at right angles from each other.  But one could imagine an evolution where the speed of the arrow on a circle depends on it's position on the circle. Then the arrows would not stay orthogonal.  It would be replacing the unitary group with the holomorphic-diffeomophism group.  States would evolve with operators $\psi'(t)=iH(\psi(t))\psi(t)$. i.e. non-linearly. But would always remain distinguishable.  Would this be against some physical principle?  Edit: Although the arrows would move around the circle at different speeds they would stay on the circle and hence the evolution is still unitary and hence states would always stay the same length. You would simply have a unitary operator dependent on the state e.g. $U(\psi(t))$. e.g. $\langle A(t)|A(t)\rangle$ would always stay the same value. But $\langle A(t)|B(t)\rangle$ would not.


What is the difference between covariance and correlation?

I am analysing stock returns and whether they move in the same or opposite directions across different regions, investment styles or company sizes.   Which of the covariance or the correlation gives the best measure of this? And what is the difference between what both statistical tests tell you?


Assuming we have this circuit:     – Schematic created using  Assuming D1 is a silicon diode and D3 is a germanium diode,Will D1 be turned on so the VAB  = Vfd1 or not? I know that if we didnt have the resistor D1 would not turn on but now i am unsure.I also know that if we had a resistor ,with a smaller resistance than R1, in series with D1 both would turn on. [] I assumed that D1 conducts and found the current 0.003A.But I assumed D1 conducts it may not what should I do from here?


Multiple resistors in series instead of using a single resistor has any advantage: heat produced by the resistors of diffent watts are different?

I have two doubts, requesting you to answer my doubts separately. :)  1) I need a resistance of 'X', so is it better to use a single resistor of 'X' value or multiple resistance of r1+r2+r3='X'? What  I mean is using multiple resistors in series instead of using a single resistor has any advantage? Will it reduce the resistors getting overheated?  2) Consider a 1W 2k2 resistor and a 1/4W 2k2 resistor. Is the heat produced by resistors of different watts different? Which resistor will get more heated in the same conditions (I mean the current, voltage etc given both resistors are same)  Regards, Kiran.


Invalid Data Source when importing geojson to QGIS

Im trying to import geojson, I add data, select protocol and use the uri  QGIS says "Invalid Data Source:  is not a valid or recognized data source"  I've followed the tutorial here  but I cant get the data to come in, any ideas? I'm using QGIS version 2.18.13


C# implementing dispatcher in async/await code

I have a wpf app in which one of the functions is to copy files. It functions correctly but can sometimes freeze the UI, so I am trying to add async/await functions to it. this is the code: if (dialog.ShowDialog() == System.Windows.Forms.DialogResult.OK)         {             string[] files = filePickedTextBox.Text.Split('\n');             await Task.Run(() =>                 {                     foreach (var file in files)                     {                         try                         {                             AddValueLoadingBar(20, true);                             File.Copy(file, Path.Combine(dialog.SelectedPath, Path.GetFileName(file)));                             newDirTextBox.Text = Path.Combine(dialog.SelectedPath, Path.GetFileName(file));                         }                          catch(Exception ex)                         {                             newDirTextBox.Text = ex.ToString();                         }                          finally                         {                             AddValueLoadingBar(100, true);                         }                     }                                     });  I have tried adding dispatcher.invoke in several locations but always get an error that it's asking for a request from a different thread, when it needs to talk to the textbox. I've been at this for hours and have searched many stackoverflow threads and other documents online but I cant figure out how to implement this. Also I know my progress bar implementation sucks..but I'm not worried about that at the moment since I cant get this to run without freezing in the first place. Any help would be great. Thx


I am creating a simple animation with flame. I followed a tutorial and flame appears in viewport but is not present when creating an animation or image. I am using Blender Render (not Cycles and GPU which seems to be a common problem). What seems to be my issue?


Latest MiKTeX update breaks XeLaTeX + fleqn

I updated the MiKTeX on my system two days ago. After that, compiling my codes using XeLaTeX gives the following error:  ("C:\Program Files\MiKTeX 2.9\tex\latex\base\fleqn.clo" File: fleqn.clo 2015/03/31 v1.1i Standard LaTeX option (flush left equations) \mathindent=\dimen102  ! Undefined control sequence. l.50 \IncludeInRelease                   {2015/01/01}{\[}{Make \[ robust}%   Here is the MWE:  \documentclass[fleqn]{article}  \begin{document}     Hi! \end{document}   I have tried the following:   Reinstalled MiKTeX; Refreshed the file name database; Updated all format files;   but all those were to no avail.  Does anyone have any idea on what else I can do?    EDIT:  This is XeTeX, Version 3.14159265-2.6-0.99991 (MiKTeX 2.9 64-bit) (preloaded format=xelatex 2015.2.18)  18 JUN 2015 00:48 entering extended mode **Sandbox.tex (Sandbox.tex LaTeX2e <2014/05/01>


Is it OK to call a professor by his first name when he/she signs emails by only first name?

If a professor in a North American country presents his- or herself by his/her first name in email messages, does this mean that students can refer to him/her by his/her first name? Or is this generally not a good idea, unless the professor has explicitly mentioned that he/she can be referred to by first name? I've noticed that most professors, who prefer to be referred to more formally, do not sign their emails with just their first names, but usually initials or first and last name.


"Heard me [infinitive]" vs. "heard me [present participle]"             At that time, you wouldn't have heard me talk about it.   At that time, you wouldn't have heard me talking about it.         At that time, you wouldn't have heard me condemn it.   At that time, you wouldn't have heard me condemning it.         Which one of the above sentences are incorrect and why?


How is Rey capable of flying a spacecraft in “The Force Awakens?”

I must have missed something, because  Rey is a scavenger who dismantles spacecraft, etc., and can drive a speeder/swoop.   It’s likely she has never even seen someone operate a spaceship. Are we to believe that their purported background is enough to inform them on the operation of these, to where they’re doing all kinds of fancy tricks within two minutes of their first moment behind the controls?


Find $\lim_{n \to \infty} \frac{n\ln(n)}{\ln(n!)}$

The answer is  $$\lim_{n \to \infty} \frac{n\ln(n)}{\ln(n!)}=1$$ but I have no idea how to solve it. I tried to apply the L'hospitals rule since top and bottom tend to infinity, but $$\frac{d}{dn}\log(n!)=\frac{1}{n}+\frac{1}{n-1}...$$  and I don't know if that helps or not. Thanks for any hints/answers.  UPDATE: Thank you all for the answers, I am currently working through them to see if I understand it. I don't know why you all have been downvoted. It wasn't me!


Applying Fourier transform to a gaussian

Let $$G_\beta(w) = e^{\beta w^2}$$  Now I get the process of applying a fourier transform (or inverse) to get a new  gaussian:  $$G_\beta(x) = G_\beta(0) e^{\frac{-x^2}{4\beta}}$$  but in doing the derivation the constant $G_\beta(0)$ never arose. I know how to calculate the constant, but where did it come from in the derivation?  edit: Fourier form used: $$\int_{-\infty}^{\infty} f(w) e^{-iwx} dw$$


How do I get Askubuntu.com to recognize the fact that i'm already logged-in on Stackexchange?

I have a profile on AskUbuntu.com which is recognized on my StackEchange profile (). I have already asked and answered questions there. But even though I'm logged in stack exchange, Askubuntu does not see me as logged in. I have a long history of problems with that and though I have been able to access it up to end 2018, and I don't understand why it can't do it anymore. I have seen multiple questions about similar problems, but they all are older than 2018 and do not really helped me solve it. Amongst other, they proposed to log in with the same user and password, but using the same user and password on two different log in systems is a security hole. either your credential cookies are shared, or one should use different logging info. EDIT: it has been suggested to deactivate third party cookies blocking, but I do not want to ruin my browser's tracking protection.


How can I transfer a Minecraft Java Edition save to Minecraft Windows 10 (Bedrock) Edition save?

I have a Minecraft Java Edition file that I would like to convert to use in Minecraft Bedrock Edition on Windows 10.  Is there any way to do this?


Have any conclusions been made regarding the interaction of Covid-19 and ACE inhibitor medications?

About two months ago, I started to see articles appear regarding the potential interactions between ACE inhibitor medications (commonly used to treat high blood pressure) and the severity of Covid-19  The articles centered around the idea that Covid-19 attaches to the ACE2 enzymes and people taking these medication have more of them.  Various studies have been conducted questioning if it would make the people taking these medications more prone to infection, or if the infections would be more severe, etc. Some hypothesis was also made that a higher level of ACE2 could have a protective role if an infection is established.  A quick search returns many links and all of them seem to say that more research is needed. The general conclusion is that people taking these medications should continue to take them for now. Many of these papers are in pre-print, some by people that do claim receiving grants from companies manufacturing these drugs, etc.  Has a consensus been somehow reached? or are things still totally fuzzy in that domain?


is there any way (what is the easiest way in bash) to combine the following:  mkdir foo cd foo   The manpage for mkdir does not describe anything like that, maybe there is a fancy version of mkdir? I know that cd has to be shell builtin, so the same would be true for the fancy mkdir...  Aliasing?


Replacing a 1963 GE 125 Amp, 240V service panel

In a recent question I asked about finding parts for my old 1960s electrical panel. I've given up on finding parts, and this new question is about replacing it with a new, modern panel:  One of the lugs burned up in my house's service panel. It was installed when the house was built in 1963. The lug is integral to the panel, and the panel is no longer available. I've looked for used panels of that model -- a GE TRX2012F -- but did not find any. So I'm told I need a new service panel.   I want to do the replacement myself. I've done minor DYI electrical work but nothing this involved. I'm reading and watching what I can find on replacing electrical panels. Can anyone offer answers to any of my questions below?  1) First, any suggestions on what panel to choose? The current one is installed flush in an unfinished stud wall. But surface-mount on top of the studs sounds fine to me too. There is about 14.5" between the studs, and they are about 3.5" deep. There is no real limit on height except that some bolts for the meter pipe extend into the wall about 6 - 7 inches above where the feeder wires come out of the wall from the meter.  2) Next, should I expect to reuse the breakers, or do I need new ones? If new ones, can you suggest what I need?  3) Regarding the fat black wires running from the breaker at the upper left down to between breakers below -- would I be duplicating that, or is that done differently in today's panels?  4) I'll need to know how to shut off the power to the panel box. If I understand correctly that would be done at the meter. And since the meter is locked by the power company, I believe that would mean calling them and asking them to turn it off, then asking them to come out and turn it back on when I'm done. Is that correct?  5) Are there any other components, or any special tools, I'll need?  Thanks! Pictures below:              More pictures:


Are all means of heating equally efficient?

In terms of cost of electricity, does it matter if I heat my room using a space heater, an open oven, a flood light, an ASIC? Assume no energy escapes the room, that the heat quickly becomes uniformly distributed, and ignore the fact that these produce heat at different rates. Consider only the amount of heat produced per unit of electricity.


Adding numeric navigation to Custom Post Type with no truncating

I am building a custom WordPress site for an artist with some Custom Post Types set up in it to display his artworks (I set up several Custom Post Types such as Artwork-painting, Artwork-sculpture etc).  On each Custom Post Types post page, I want to put navigation buttons that is more complete than just Previous and Next button - I want to show links to all the posts within that Custom Post Types. For example, there are 50 posts in the artworks-sculpture Custom Post Types. The navigation will have the links to all the posts -  1 to 50  ( 1 2 3 until 50 ). I don't want hiding/truncating any numbers. ( I see some sites condense the numeric pagination with ellipsis, I don't want that).  How can I do that?


Last week I've noticed that my C drive was out of disk space. So for the past few days I've been looking into what folders occupy my disk space, and started cleaning up a bit. I've ended up freeing 75 GB. Ever since, I've seen that my efforts to free up disk space were useless. Today already, I'm right back at only 12 GB free disk space again. Once again I've started looking into what folders are taking up space.  Read this picture as follows:  Invisible files/folders are shown in Windows Explorer My SSD has a capacity of 475 GB All files/folders on my disk are taking 166 GB (only 1/3 of my capacity) My disk is full  Why does this keep happening? Where do these 309 Gigabytes go to? I'm a .NET developer, so I , but even so, the file size of the SQL-server cache folders should show up in the measurements.  EDIT I did a scan using the tool that @Señor CMasMas suggested (run as administrator)  And it's indeed the folder C:\Program Files\Microsoft SQL Server\MSSQL15.MSSQLSERVER\MSSQL\Log\Polybase\dump that's taking up all disk space (literally 256 GB), even though you can't see it under the Program Files folder size. EDIT 14/06/2021 I had installed the latest version of SQL Server. Now we're 3 weeks in, and once again my C drive is getting seeded with the same file:


How does Hendo hoverboards achieve the self-propelling motion? What is the MFA?

From what I understand of the idea behind , they use .  I also understand that it uses Lenz's law and eddy currents. And that the hendo-hoverboards only work in non-ferromagnetic material.   From what I re-call, Lenz's law states that eddy currents are created when magnets are moved relative to conductive materials. In particular, lenz's law states that eddy currents are formed when there is a change in magnetic flux. So they used magnetic field architecture.   Magnetic Field Architecture (MFA) is a design where there are 4 electromagnets on the base of the board that propels on non-ferromagnetic material.   However, I don't understand how that works? How do they calculate the gravitational pull such that the MFA exerts more force to over come that gravitational pull?


When is a CDATA section necessary within a script tag?

Are CDATA tags ever necessary in script tags and if so when?  In other words, when and where is this:  <script type="text/javascript"> //<![CDATA[ ...code... //]]> </script>   preferable to this:  <script type="text/javascript"> ...code... </script>


Fatal error: Allowed Memory Size of (X Size) when running drush migrate-upgrade

I'm trying to use drupal migration module with drush to migrate a database. I'm getting this error below.  Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 32 bytes) in /Applications/XAMPP/xamppfiles/htdocs/drupal-eight-iom/core/modules/migrate_drupal/src/Plugin/migrate/source/DrupalSqlBase.php on line 76  I have already tried editing the memory_limit on php.ini file  memory_limit=5024MB  Not sure what else I need to do in order to make it work. I'm using Drupal 8.4.4  $databases['default']['default'] = array (   'database' => 'drupal-eight-iom',   'username' => 'root',   'password' => '',   'prefix' => '',   'host' => '127.0.0.1',   'port' => '3306',   'namespace' => 'Drupal\\Core\\Database\\Driver\\mysql',   'driver' => 'mysql', );  $databases['upgrade']['default'] = array (     'database' => 'drupal-seven-iom',     'username' => 'root',     'password' => '',     'prefix' => '',     'host' => '127.0.0.1',     'port' => '3306',     'namespace' => 'Drupal\\Core\\Database\\Driver\\mysql',     'driver' => 'mysql',   );   $settings['install_profile'] = 'standard'; $config_directories['staging'] = 'sites/default/config'; $config_directories['sync'] = 'sites/default/files/config_zB_DnNUK68i5Owp5a8FzTiClQfp3d3jrwcy0_HuS1hNCGv9Y_Iva2Ahm8LCH-P0j0M2jwmQAsA/sync';


Problem with Rest Webservice Code coverage

I have the following set of lines in my code      RestRequest req = RestContext.request;     RestResponse res = RestContext.response;     AreaRequestWrapper areaRequestRecord = (AreaRequestWrapper)System.JSON.deserialize(requestString, AreaRequestWrapper.class);             if(areaRequestRecord.OpportunityId == null || areaRequestRecord.OpportunityId == '')             {                 res.statusCode = 401;                  res.responseBody = Blob.valueOf(res.statusCode+' : Mandatory field OpportunityId was not sent in the Request JSON');             }   My issue is that, when I am writing the test class for the above code, the the code is covered till line   res.statusCode = 401;   But the responseBody line does not get covered.


I've heard that you can't use extend twice.  I have two classes:  Base32 and SecureRandom  Which I need for TOTP.  How can I use both of these for it?


apt-get complains about untrusted packages

Since installing Kubuntu 13.04, apt-get (and all other packaging tools) complain about untrusted packages. As an example, when I try to install ruby1.9.1-dev:  # aptitude install ruby1.9.1-dev   The following NEW packages will be installed:   gcc{a} gcc-4.7{a} libc-dev-bin{a} libc6-dev{a} libgcc-4.7-dev{a}    libitm1{a} libquadmath0{a} linux-libc-dev{a} manpages-dev{a}    ruby1.9.1-dev  0 packages upgraded, 10 newly installed, 0 to remove and 3 not upgraded. Need to get 15,8 MB of archives. After unpacking 41,0 MB will be used. Do you want to continue? [Y/n/?]  WARNING: untrusted versions of the following packages will be installed!  Untrusted packages could compromise your system's security. You should only proceed with the installation if you are certain that this is what you want to do.    ruby1.9.1-dev gcc-4.7 libgcc-4.7-dev libquadmath0 gcc libc6-dev libitm1    linux-libc-dev manpages-dev libc-dev-bin   Do you want to ignore this warning and proceed anyway? To continue, enter "Yes"; to abort, enter "No":    I'm pretty sure gcc is an official package :-)  What's causing this and how can I get rid of it?


I cannot get VirtualBox to install on my Ubuntu Linux machine. I type in sudo apt install virtualbox And it reads the dependency tree and asks me if I want to install 161 MB of information. I confirm, and get the following string of error codes: Do you want to continue? [Y/n] y Err:1 http://archive.ubuntu.com/ubuntu disco-updates/main amd64 dkms all 2.6.1-4ubuntu2.5   404  Not Found [IP: 2001:67c:1360:8001::23 80] Err:2 http://archive.ubuntu.com/ubuntu disco/universe amd64 libgsoap-2.8.75 amd64 2.8.75-1   404  Not Found [IP: 2001:67c:1360:8001::23 80] Err:3 http://archive.ubuntu.com/ubuntu disco/multiverse amd64 virtualbox-dkms all 6.0.6-dfsg-1   404  Not Found [IP: 2001:67c:1360:8001::23 80] Err:4 http://archive.ubuntu.com/ubuntu disco/multiverse amd64 virtualbox amd64 6.0.6-dfsg-1   404  Not Found [IP: 2001:67c:1360:8001::23 80] Err:5 http://archive.ubuntu.com/ubuntu disco/multiverse amd64 virtualbox-qt amd64 6.0.6-dfsg-1   404  Not Found [IP: 2001:67c:1360:8001::23 80] E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/main/d/dkms/dkms_2.6.1-4ubuntu2.5_all.deb  404  Not Found [IP: 2001:67c:1360:8001::23 80] E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/universe/g/gsoap/libgsoap-2.8.75_2.8.75-1_amd64.deb  404  Not Found [IP: 2001:67c:1360:8001::23 80] E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/multiverse/v/virtualbox/virtualbox-dkms_6.0.6-dfsg-1_all.deb  404  Not Found [IP: 2001:67c:1360:8001::23 80] E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/multiverse/v/virtualbox/virtualbox_6.0.6-dfsg-1_amd64.deb  404  Not Found [IP: 2001:67c:1360:8001::23 80] E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/multiverse/v/virtualbox/virtualbox-qt_6.0.6-dfsg-1_amd64.deb  404  Not Found [IP: 2001:67c:1360:8001::23 80] E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?  I'm a rank amateur at this so the solution is hopefully simple. Any help with this would be appreciated.


Populating a field in an attribute table with a consecutive number sequence?

I know that this is probably a very basic question but I can't seem to find an answer through Google searches.   I would like to create a field in an attribute table (in ArcMap 10.2) for a Number Label (i.e.. 1, 2, 3, 4, ... etc.) is there a way to calculate this field with the field calculator rather than typing in each individual number?


Short story where man rejected from learning program and identified as untrainable

I read a story when I was a child in the 70's that I cannot forget. It may have been from fiction written between 1950 - 1975. My older brother subscribed to several short fiction scifi magazines.  The story is of a young man who lived in a village. When villagers turned 16 their brains were measured as to what they could best hold.  At age 18, a specialized program was uploaded to their brains to make them the best possible specialist they could be, as needed by the society. One person would become the best keymaker, the best tailor, etc. Each persons identity in the social structure was based on optimizing the brain for their best possible application. The citizens were very proud of their occupations.  The young man was identified as imbecile and untrainable. He was sequestered to a prison. He read books and questioned his detainment - eventually breaking out. He goes on a journey to find out why he was imprisoned since he has demonstrated he is intelligent by learning so much while in prison. I will refrain from saying the ending...  Please help me identify this!


How can I compare the schema of two databases?

Is there a way to find the differences in two SQL Server databases (schema only).  One is local and the second is at a customer's site.  We are experiencing problems with crystal reports running some reports and some code not executing and it would appear that the schemas don't match.  Can I run the same command on both databases and compare the results to tell where the differences are?


Markdown in chat works on multi-line messages on the star board

Markdown in chat is broken disabled on purpose for multi-line messages,  and appears to be .    However, if you star a multi-line message, Markdown actually works:    As you can see, over at the right, Can you star this message? appears in italics.  The behavior should probably be made consistent, so it would make sense to break disable Markdown on the starboard for these messages as well.  (Or, y'know, , since this is basically a bug rather than a feature on the natural language sites.)


I understand that wheels should be trued for efficiency. Are there any safety risks (or risk  of damaging the bike) in using untrued wheels?  Are the risks different between wheels untrued left-right and up-down?  My question is motivated by the following fact: I have an up-down untrued wheel and not much time to take it to the shop, should I keep using the bike?


How to count the number of occurrences of an element in a List

I have an ArrayList, a Collection class of Java, as follows:  ArrayList<String> animals = new ArrayList<String>(); animals.add("bat"); animals.add("owl"); animals.add("bat"); animals.add("bat");   As you can see, the animals ArrayList consists of 3 bat elements and one owl element. I was wondering if there is any API in the Collection framework that returns the number of bat occurrences or if there is another way to determine the number of occurrences.  I found that Google's Collection Multiset does have an API that returns the total number of occurrences of an element. But that is compatible only with JDK 1.5. Our product is currently in JDK 1.6, so I cannot use it.


18.04: ThinkPad p50 Fingerprint Scanner not working even when recommended answer tried

Installing  and  do not enable the fingerprint scanner on a  to work with Ubuntu.   If there is another linux-based OS that supports this, I would gladly switch to that, but I haven't found any.   The output from lsusb is:  Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 003: ID 138a:0090 Validity Sensors, Inc.  Bus 001 Device 002: ID 04f2:b596 Chicony Electronics Co., Ltd  Bus 001 Device 004: ID 8087:0a2b Intel Corp.  Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub   Valadity Sensors, Inc. is my fingerprint sensor. How do I get it to work in Ubuntu?


How to upgrade firmware on OKI MC562dn from USB-Stick?

Unfortunately all my attempts to connect my OKI MC562dn with the official firmware update tool fail. The hints given  doesn't work for me. The tool can't find any device in the network.  The strange thing is: The printer works fine in general. I can print from several windows PCs in the same network without problems, in color, black&white and duplex. I can ping the printer. I can manage the device with the webserver reachable at 192.168.1.21. I can even scan documents and fotos from my OKI MC562 to several different locations in my home network.  To update the firmware I also tried to connect the printer to a laptop and his USB Port. The same thing: I can print, but the update tool doesn't find the printer.  How can I update my OKI MC562 with the  and the use of a USB stick?  The  isn't clear enough for me to find all necessary files and the needed "model specific folder structure" to get it working. Has anyone done this succesfully?


If a vector subspace is in a union of other subspaces, then it's contained in one of them

Problem: Let $V$ be a finite dimensional vector space and $V_1,\ldots,V_n\subset V$ vector subspaces. Show that if $W\subset V$ is a vector subspace and   $$W\subset V_1\cup\cdots\cup V_n,$$   then   $$W\subset V_k$$   for some $1\le k\le n$.   I get the intuitive idea of why this should hold by drawing pictures, but I can't prove it rigorously. I know that if $V_1,V_2$ are two subspaces and $V_1\cup V_2$ is also a subspace, then $V_1\subset V_2$ or $V_2\subset V_1$. Does that help?


How to successfully put a bibliography in a report on TexShop?

I'm trying to put a bibliography in my LaTeX document, but I get various errors when I run it in BibTeX (saying no \citation found etc.), and no bibliography is printed in the PDF when I typeset it in LaTeX. My code reads as follows:  \documentclass[12pt]{report} ... \usepackage{biblatex} \addbibresource{SUSYBib.bib} ... \begin{document} ...\cite{1}... ...\cite{2}... \nocite{*} \printbibliography \end{document}   And my .bib file reads as  @book{1, title={The Schrödinger Equation}, author={F. A. Berezin, M. A. Shubin}, year={1983}, publisher={Moscow State University, Moscow}, pages={57-59} } @book{2, title={An Introduction to Measure Theory}, author={Terence Tao}, year={2011}, publisher={American Mathematical Society}, pages={91} }


MySQL injection protection and vulnerability signs using PHP

What are the best ways to protect from MySQL injection? What are weaknesses I should look out for?  I know what it is, but I really have no idea how vulnerable I might be. Though I have taken (what I think to be) steps toward protecting myself and my database.  Is there any sure-fire way of stopping someone?  BTW...I write in PHP:)


A question on  got me thinking, ignoring , "Do we weigh less in the morning?"  During the night, the sun is above us, and the earth below us. Conversely, at night, both the earth and the sun are "below" us. Our mass obviously stays the same, but would there be a greater gravitational pull on us since the added gravity from both the earth and the sun on the other side are acting on us?  Or do we not notice the gravitational pull from the sun, for the same reason astronauts aboard the ISS don't notice the gravitational pull from the earth?


Evaluate forecasting ability of GARCH models with RMSE and MAE

I am evaluating different forecasting models and their ability to forecast index volatility during period of market turmoil, using two measurements, Root Mean Square Error and Mean Absolute Error. For the previous evaluated models, ARMA (1,1) as an example, I was able to obtain the residuals and calculate the RMSE quite easily in Stata.   When estimating the GARCH (1,1) model in Stata I am however not able to correctly obtain the residuals in the post estimation procedure, no option to directly obtain the RMSE is available. Perhaps I have misunderstood how one should evaluate the forecasting ability of GARCH models, since the models specifies the conditional variance unlike ARMA which specifies the conditional mean.   Does anyone have a suggestion on how to obtain these evaluation measurements after estimating a GARCH model? And preferably how to do it in Stata.


Exporting multi layered Illustrator to Photoshop

Is there a way to export large multi-layered Illustrator file to Photoshop?  When I export with preserve layers and text edit-ability, the complex layers are flattened. I've reorganized my layers to have simple groupings but that's time consuming.  Is there a more effective way of doing this? Or script to automate it?


I would like to delay a hover event in jquery.  I am reading from a file when user hovers over a link or label.  I don't want this event to occur immediately in case the user is just moving the mouse across the screen.  Is there a way to delay the event from firing?  Thank you.  Example code:  $(function() {     $('#container a').hover(function() {         $('
').load('ReadTextFileX.aspx',             {filename:'file.txt'},             function() {                 $(this).appendTo('#info');             }          );     },         function() { $('#info').remove(); }     }); });   UPDATE: (1/14/09) After adding the HoverIntent plugin the above code was changed to the following to implement it.  Very simple to implement.  $(function() {     hiConfig = {         sensitivity: 3, // number = sensitivity threshold (must be 1 or higher)         interval: 200, // number = milliseconds for onMouseOver polling interval         timeout: 200, // number = milliseconds delay before onMouseOut         over: function() {             $('
').load('ReadTextFileX.aspx', {filename:'file.txt'},                 function() {                    $(this).appendTo('#info');                 }              );         }, // function = onMouseOver callback (REQUIRED)         out: function() { $('#info').remove();  } // function = onMouseOut callback (REQUIRED)     }     $('#container a').hoverIntent(hiConfig) }


Why does this property hold for odd integers except for 5?

In working on a game I noticed that if I were to take the first ten multiples of seven and consider the last digit of those numbers, the result was exactly one occurrence of each unique digit, zero through nine:   1 × 7 = 7   =>  7  2 × 7 = 14  =>  4  3 × 7 = 21  =>  1  4 × 7 = 28  =>  8  5 × 7 = 35  =>  5  6 × 7 = 42  =>  2  7 × 7 = 49  =>  9  8 × 7 = 56  =>  6  9 × 7 = 63  =>  3  10 × 7 = 70 =>  0   This struck me as surprising (I'm not a mathematician), so I tried the same thing with all of the other numbers and found the same was true for all of the odd single-digit numbers except for 5.  Why does this property exist? Is there a name for this? What is special about 5 that causes it to not have this property?


How do I change the login screen in Ubuntu 16.04+?

The  in 14.04 [EDIT ] don't work in 16.04. The "custom" background shows for a split second and then fades to the Ubuntu one. So, how do I change the login screen background in 16.04?  [Edit: this post is not a duplicate because all other related questions specifically refer to previous versions of Ubuntu, and the solutions to those do not apply here (as they do not work on 16.04).]


A friend of mine suggested that I learn Swift, as it would help me get a job that I had applied for, and I thought this was a good idea. The only problem: I don't own a Mac computer, or anything with OS X. Is there any way I can try programming on Swift in a non-OS X environment, like Windows or iOS? Any help would be appreciated. I don't want to have to buy another computer just to learn a language.


How does a body on the surface of the earth apply a force on the ground? Since neither the body nor the surface of the earth is in motion, there is no acceleration and, hence, there can be no force because force equals mass times acceleration.


How can I control the master volume in Windows?

Some keyboards have volume controls on them that can be pressed anytime to control the master volume.  My keyboard does not have that.  Is there a way that I can create a key macro that will work like the volume controls on those keyboards?  It should always allow me to control the volume, even if I'm playing a game.


Factoring polynomials of the form $1+x+\cdots +x^{p-1}$ in finite field

Suppose $p$ and $q$ primes and $p$ is odd. Then, are there nice and clever ways to factorize polynomials of the form $$f(x)=1+x+\cdots +x^{p-1}$$ in the ring $\mathbb{F}_q[x]$ ? What about the case when $q=2$ ?   I know that there are factorization algorithms but they are too general. I want to know if there are clever ways to do this for these special type of polynomials. Like for example, in $\mathbb{F}_2$ one might add terms $x^r+x^r$ and rearrange them so that $f(x)$ gets factorized.  In case there are no good methods to factorize, are there nice ways to check whether $f(x)$ is irreducible in $\mathbb{F}_q[x]$ ?


Will we feel the gravity of a star 10 light years away for the next 10 years if, somehow, it vanishes today from its position?

I was watching a relativity video, and although I am not sure, I felt that it was trying to tell that the effect of gravitation of a body is instantaneous, in the sense that a sudden change in the mass of a body will instantaneously be felt by any object at a distance, even before light can be exchanged between them. So I want to make sure if its true. You don’t have to explain me why this is so if you don’t wish to. Also, please tell me if this has been experimentally established, or it is just a theory.


Google AdSense: what does function(G,o,O,g,L,e) do?

I am trying to understand some of the source code behind Google AdSense. Google's code generator () says to put the following in the HEAD element: <script type="text/javascript" charset="utf-8">     (          function(G,o,O,g,L,e) {             G[g]=G[g] || function(){(G[g]['q']=G[g]['q'] || []).push(arguments)},                      G[g]['t']=1*new Date;              L=o.createElement(O), e=o.getElementsByTagName(O)[0];             L.async=1;             L.src='//www.google.com/adsense/search/async-ads.js';             e.parentNode.insertBefore(L,e) /* no semicolon...why? */         }      )(window,document,'script','_googCsa'); /* argument list */ </script>  My knowledge of JS syntax is not very good, and I don't know answers to the following: (1) A function inside a set of parentheses, and then what looks like an argument list, (2) No semicolon after the last line in the curly braces...what's going on here? (3) What is function(GoOgLe) actually doing? (I tried Googling "function(G,o,O,g,L,e)", but only got others' source code.) Any help would be appreciated.


Is there any front end  that sit over R and execute codes - basically making usage of R further simpler? In my team we used to run lots of statistical things using R. There are some people who are from different background and don't have  any knowledge of statistics. For them we are planning to make some front end using R. Using which they can run the analysis by doing some simple clicks.But before doing that I thought to check with you guys if there is any readily available front end for R  Thanks in advance


How to generate a subtotal amount using the DOM

i'm trying to generate a simple subtotal amount for a small shopping cart project and it does not seem like the function can see the input value  my input HTML is: <input id="valueTest1" type="text" value="0" data-price="10.99">  and i just need simply the data-price to * the value entered and then show in my subtotal HTML (shown below)
£0.00
  here is my function..  function calculateSubTotal() {     let subtotal = 0;     for (i = 1; i <= itemTotal1; i++) {          itemID = document.getElementById('valueTest1');         if (typeof itemID === 'undefined' || itemID === null) {             alert("No such item - " + "valueTest1");         } else {             subtotal = subtotal + parseFloat(valueTest1.value) * parseFloat(itemID.getAttribute("data-price"));         }      }     console.log(valueTest1.value)     document.getElementById('itemTotal1').innerHTML = "£" + subtotal; }   I can console.log the input (valueTest1.value) outside of the function and it shows 0 but when i try to console.log the input in the function i get nothing, any help would be appreciated.


Intel-microcode package upgrade in ubuntu 18.04 leads to unbootable system

in my earlier question you can find at:   i describe my error:     I'm using an Asus Zenbook UX562F with an integrated GTX 1050 Max-Q.   After the installation, I installed Nvidia-390 and updated the kernel   with ukuu to 4.20.17 to fix no sound issue.      After the reboot, everything went well and I did:      apt-get update apt-get upgrade + J      All was done well, so I restarted and on the next boot after selecting   Ubuntu in GRUB it gave me a long black screen (violet screen) where   nothing changes after so much time.      I tried to add nomodeset and noveau.modeset=0 single and together but   didn't help so I don't know what to do.   After investigating deeper by installing packages and try to boot i found out that the package which is causing the error is:  intel-microcode   when i purge and block this package with:  sudo apt-get purge intel-microcode sudo apt-mark hold intel-microcode   before upgrading wuth  sudo apt-get upgrade   my system is able to boot normal.  The problem i see is that as i understand it the package protects my intel cpu  Intel® Core™ i7 8565U 1.8 GHz   is vulnearable to meltdown attacks which get fixed by the package.  What can i do to fix the vulnearbility and also get my system to a bootable state?  Thanks for your help Vimu  Edit: I used the manual update technique mentioned at (in german):    and i used the files from the intel github repo:    with the following code mentioned in the tutorial to update the firmware microcode files  sudo cp intel-ucode/06-8e-09 /lib/firmware/intel-ucode/ echo 1 | sudo tee /sys/devices/system/cpu/microcode/reload   i overwrote the old microcode firmware with the newest available on the intel repo  it leada to a bootable system  will this be the best possible fix without upgrading the intel-microcode package provided by apt?


How to split comma separated string using JavaScript?

I want to split a comma separated string with JavaScript. How?


How to limit 1 connection per 5 seconds? (IPTABLES)

I want to limit 1 connect per 5 seconds using IPTABLES for people, which are connecting to port "12871/12881". I was trying to find rule for it, but ineffectively. It must be like a "queue" of connects - for example 1 connect per 5 seconds.  I had here discussion:   but Im not able to reply on this account, previous was unregistered and logged me out.