I have tried looking around for the answer, but I kept on getting answers for playing a sound on death. I want to play a sound when player respawns. Any suggestions?

I have a command block line set up so that it detects for a players death, then gives them weakness for 600 seconds. It applies weakness to soon before they get out of the respawn time. If there is not way to delay a command is there a way to detect a player respawn?


For two manifolds $M$ and $N$ I'm trying to prove that $M \times N$ is orientable if and only if $M$ and $N$ are orientable.  My attempt so far:  $\impliedby)$ Assume $M, N$ are orientable. Then $\widetilde{M}$ and $\widetilde{N}$ the orientation double covers of $M$ and $N$ are disconnected. But $\widetilde{M} \times \widetilde{N}$ is the orientation double cover for $M \times N$. Since $\widetilde{M}, \widetilde{N}$ are disconnected certainly $\widetilde{M} \times \widetilde{N}$ is disconnected. Therefore, $M \times N$ is orientable.  $\implies)$ Proceed by contradiction. Assume $M \times N$ is orientable and WLOG $M$ is nonorientable. Then the orientation double cover $\widetilde{M\times N}$ is disconnected. Now note that $\widetilde{M}$ is connected since $M$ is nonorientable. So $\widetilde{M} \times \widetilde{N}$ is connected since the product of a connected space and a disconnected space is connected. But $\widetilde{M\times N} = \widetilde{M} \times \widetilde{N}$, so $\widetilde{M\times N}$ is connected. But this is a contradiction, therefore it must be that $M$ is orientable.  This completes our proof.   The validity of this proof hinges on two assumptions that I'm unsure about: 1. $\widetilde{M\times N} = \widetilde{M} \times \widetilde{N}$ 2. The product of a connected space and a disconnected space is connected.  Are these two facts true? Is my proof valid? How do I go about proving these two necessary assumptions if they are indeed true? If I'm totally going the wrong way could someone send me in the proper direction?  Thanks

I'm studying orientability of manifolds currently and I'm having trouble to prove the following: $M\times N$ is orientable iff $M$ and $N$ are orientable.   I am able to prove that the product is orientable if components are orientable (chart is $\{(U_\alpha\times V_{\beta},\phi_\alpha\times \psi_\beta):(\alpha,\beta)\in A\times B \}$, and $\det J=\det J_1 \det J_2>0$ by Cauchy-Binet's theorem), but I don't know how to prove the other direction.   So why this holds: if $M\times N$ is orientable, then $M$ and $N$ are orientable?  Thanks in advance.


We would like to pick up a rental car at the Seatle, WA airport and two weeks later return it to the airport in Anchorage, AK. Don't understand why we can't find any agencies that will do this. Does anyone have any ideas? We have put off this trip for years because we can't seem to work it out.

I'm having a difficulty in finding one way car rentals from Alaska, which I can return in Seattle.  Do all the main rental agencies restrict such one-way rentals, as they involve crossing through Canada, before entering the lower 48 states?


I have an   let obj = { a:'Nasa', b:'Zezo'}   Is there a way to make that object look like obj = { a:'Nasa' }  I am not looking at delete operator because the key still exists.  the delete operator leaves me with {a:'Nasa', b:null }

Say I create an object as follows: let myObject = {   "ircEvent": "PRIVMSG",   "method": "newURI",   "regex": "^http://.*" };  How should I remove the property regex to end up with new myObject as follows? let myObject = {   "ircEvent": "PRIVMSG",   "method": "newURI" };


This is my first time getting Linux. I burned Linux to my disk. Every time i reset my computer it says "Windows could not install (or something like that). It says like something is missing. It worked when I installed it on  Virtual Box. But it won't let me install on my laptop. Please help.

I used to have Xubuntu 11.10 side-by-side with my Windows installation, installed via WUBI from Windows. After upgrading to Windows 10, however, this doesn't start any more, so I wanted to reinstall it.  However, I have noticed that WUBI is not included on the new 15.10 Xubuntu iso, and is also generally not supported any more.  Is there any way I can achieve what I had before, without partitioning my hard disk?


A vector space must satisfy closure under addition and multiplication. Sorry if this is obvious but does that mean that, assuming the normal rules of arithmetic and excluding the trivial examples like $V=\{0\}$  it is impossible for a vector space to have a finite number of elements? (since for every two elements $u,v \in V$ there must be another number $u+v \in V$)

I have only seen infinite vector spaces and the one finite vector space i.e the trivial vector space $\{0\}$. Is there any other finite vector space?


If a boggart appeared to someone as a basilisk, would direct contact with its eyes kill that person?

When it appeared as a snake to Parvati, would it really be able to bite or choke her, or is it just scaring without actually being able to attack?


When I see $PATH it seems like following . /bin:/bin:/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin /bin is duplicated in path, my question is how to drop duplicate these in path ? Are there any good way to achieve this? Thanks

Is there an easy way in zsh to add a directory to my PATH only if it's not already present? (or, more generally, any environment variable). I've tried:  PATH+=/my/directory   ... but if that's executed twice, it gets added twice.


When reading a column of integers (land cover classes) from a CSV file, ArcMap (10.5) automatically assigns a field type of 'string', rather than a number format (e.g. 'Long'). This makes it so you cannot use that field for symbology or mathematical operations.  Strangely, ArcMap reads the column of numbers from an original CSV as integers, but not from the version modified in Excel.  While I could add a field and then use field calculator to convert the string values to numeric, which is the only solution I could find online, this shouldn't be necessary. There must be a way to get numeric fields in CSVs to be interpreted as numeric, as most CSVs work fine.  Edit: This question differs from the suggested duplicate in that it relates to CSV files and not excel files. Also the CSV file is not being imported with Table to Table, or Excel to Table, but is being used directly as a table in arcpy. The workaround also differs from those other 'solutions', which are also just workarounds. None of the workarounds, including my own, explain the fundamental underlying reason why ArcMap only sometimes decides to read number columns as text. Calling them solutions is like a doctor saying that a painkiller will cure the disease. I don't want to have to convert the file unnecessarily.   Where is the real solution to why ArcMap only sometimes interprets a number column as text?

I have a large Excel spreadsheet that contains lots of numeric data that I would like to import to ArcGIS 10.2 as a table using the  tool.   The frustrating thing is that the numeric fields in Excel are repeatedly not recognised and are assumed as being text. I have set the cell format to numeric, cleared any possible blank cells, tried importing as CSV, removed invalid characters in the field headers. yet any possible iota of success evades me.  Does anyone know why this may be happening and/or how it can be resolved?


I am trying to find a cubic polynomial over GF(5) that evaluates to zero at the points (1,2,0),(2,0,0),(1,4,1),(-2,-1,-1),(-3,2,1),(1,-1,0),(2,-3,1),(-3,-2,2),(1,-2,1).  Clearly the zero polynomial would satisfy the condition, thus I'm looking for a proper cubic polynomial. I note that the generic form of such a polynomial is $f= ax^3+ by^3+ cz^3+ dx^2y + ex^2z+ fy^2x+ iy^2z+ gz^2x+ kz^2y+ lxyz$, that is I need to solve for the coefficients $a,b,\ldots,l$.  I would prefer to do this calculation in GAP as I am using the software already for other calculations.

given a polynomial $p(x,y)$ from $\mathbb Z[x,y]$. I want to substitute $x=1$ leaving $y$ as it is. The command Value(p,[1,y]) does not work. Can you give me a hint?  After that it gets a little more complicated. Let  $$p(x,y)=x^6+y^6$$ After substituting $x=1$ we have $p(1,y)=1+y^6$. Given a natural number $j$. I want to find all expressions $y^j$ in $p$ and substitute these $y^j$ by $1$ and the others by $0$. In this case (and for $j=6$) we would get $1+1=2$. If $$p(x,y)=x^4y^2+x^2y^6$$ we should get $0+1=1$. Is there any way to do this?  Thanks for reading! edit: Well, it turns out I used the function Value wrong. The right code for my problem would be Value(p,[x,y],[1,y]). So my first question is solved.


Is there a handy reference that corelates the number of decimal points in a coordinate to the precision in meters?  I had discussions like "4 decimal places will place you within a 500 meter radius" and "6 decimal places will place you in a house". I want a reference that can clear up such facts and requirements.

I have latitude and longitude as 19.0649070739746 and 73.1308670043945 respectively.   In this case both coordinates are 13 decimal places long, but sometimes I also get coordinates which are 6 decimal places long.   Do fewer decimal points affect accuracy, and what does every digit after the decimal place signify?


I saw this movie in the early 2000s where a teenager and an older man (probably his dad) travel back in time to the middle ages. Their time machine gets broken, it is rather big and looks more like a spaceship. Like a NASA space shuttle but smaller/shorter.  They meet a group of peasants who are rebelling against the local nobles, much like Robin Hood's merry men. A guy who seems in charge of the rebels ask them who they are and what they do. The "dad" says they are inventors and the time machine is used to keep food fresh for weeks, but it's broken. Talk about a big fridge! The rebel leader laughs, "Why keep food when you can eat it?". They help camouflage the time machine until it can be fixed.   Suddenly they are attacked by a "dragon" but the teenager calms them down by telling them that it's called a Triceratops and it doesn't eat meat. He makes friends with a young guy who was impressed with his knowledge of "dragons". Somehow there is also a real dinosaur they must fend off, not quite a T-Rex but a bigger raptor maybe. He also helps them out with a battle against the nobleman's soldiers by creating some sort of electroshock device(s). When the medieval friend asks him what's that electricity he's talking about he says "it's not magic, but a form of energy, like lightning" to which he is told "So it's magic then, you really are a magician!" and he and his friends are totally in awe.  I think in the end they fix the time machine after also helping the rebels battle the oppressing feudal lord. The entire movie was rather lighthearted. This is a live action 90s English movie, nothing too fancy about it.

I'm looking for a 90s (or early 2000s) scifi (mini)series where a boy and old man chase a black guy in metal suit. I think they were going through different dimensions. I remember part of it, but I don't think I ever saw how it ended. I remember my friend telling me there was a twist at the end. I think they were trying to find something and he was always ahead of them..


Middle click to paste is making scrolling impossible in Terminal on my thinkpad keyboard because of middle click pasting.   I'd prefer to just disable it on that app, but globally would be fine.   I found this question with 1 answer but I had too much trouble with Karabiner (it broke hyperdock) and it's specifically about how to disable middle click for terminal, not globally:

I have looked all over the Net and can't find a way to disable middle-click paste in the Terminal application in Mavericks? I want it scroll but not paste.   Anybody know how to fix this? I'd sure appreciate the tip.


I've read in a book that I should "use the subjective case if the pronoun is the complement of the linking verb to be".  That is the following sentences are correct:  They believed that the thief was I. /  Hey, it's I. /  Yes, this is she. Who's calling?  OK, a rule is a rule. I don't mind using it, but I have a question for native speakers:  Is this way to say it heard in everyday speech? Will it sound deliberate/unnatural if I use it?

Upon answering the telephone, the person calling asks if Joan is available. If Joan is the person who answered the phone, should she say "This is her" or "This is she"?


Prove that for all m > n $\ge$ 1,  $ \vert x_m - x_n\vert \le \frac{K^{n-1}}{1-K}\vert x_2-x_1\vert $  Where K is a contraction factor of f, such that K $\in$ [0,1) and $\vert f(x)-f(y) \vert \le K\vert x-y \vert $  $(x_n)$ is the sequence defined as $x_1 = \alpha \in R$ and $x_n = f(x_{n-1}) $ for all $n\ge2$  I have already shown that $\forall n \ge 1$, $\vert x_{n+1}-x_n\vert \le K^{n-1}\vert x_2-x_1 \vert$,  so that can be used without proof.  I tried using induction by showing m=n+1 holds, assuming m=n+k holds, but couldn't show that m=n+k+1 holds.  I don't know if you're supposed to use induction but that's the only method I could think of.

I'm interested in convergence of $f(x_n)=x_{n+1}$ and often hear this term referenced.  What does it mean to be a contraction mapping in the context of the sequence of real numbers given by $f(x_n)=x_{n+1}$? And what does it tell us about such sequence?  A search online gives the answer given by Wikipedia, that it is a function $f$ defined on a metric space $(M,d)$ from $M$ to itself with the property that for some real number $k \in [0,1)$,  $$d(f(x),f(y)) \leq k d(x,y)$$  This definition is quite unhelpful because I barely know what a metric space is. I feel like this definition is to generalized, and I'm interested in in the specific case of recursively defined real sequences $f(x_n)=x_{n+1}$ that there should be a more specific answer to my question.


i have sql table with data as given below      emp id     empname  dept     -------    ----     ------   1              a        Hr   2              b        Hr   3              c        Tech   4              d        Hr   5              e        Admin   7              f        Tech   8              g        Admin   Now i want to pivot the above table get the result like this                  Hr    Tech    Admin                -----  -----   ----- Empname        a       c       e Empname        b       f       g Empname        d   I am just wondering is this even possible using pivoting in sql or there is any other mean to achieve this

Trying to find some simple SQL Server PIVOT examples.  Most of the examples that I have found involve counting or summing up numbers.  I just want to pivot some string data.  For example, I have a query returning the following.  Action1 VIEW   Action1 EDIT   Action2 VIEW   Action3 VIEW   Action3 EDIT     I would like to use PIVOT (if even possible) to make the results like so:  Action1 VIEW EDIT   Action2 VIEW NULL   Action3 VIEW EDIT     Is this even possible with the PIVOT functionality?


[Readers] can tell at a glance whether the paper   was written using Word or LaTeX.     -- Graham Cormode. 2009. How NOT to review a paper: the tools and techniques of the adversarial reviewer. Page 2  I just read this and started to wonder, how exactly can one tell? I only know that I could tell if our professor used Powerpoint or LaTeX for the slides, because the PowerPoint slides were scaled a lot bigger on initial zoom. But how to decide between Word an LaTeX?    Thank's for pointing to . It does bring some good points, but that question is very specific in its aim. I want to find a broader series of answers, maybe not even related to visuals.

I really want to convince my friends and family that LaTeX is the choice for them when it comes to formatting and creating beautiful documents. I am aware of the major advantages that come with using LaTeX but some are not convinced. Can someone please provide a side by side comparison of a Word document (or something of the sort) and a LaTeX document that shows the obvious and subtle differences between the two? I want people to look at it and say "Ahhh, I see it, there's a major difference".


I am trying to prove that if cardinality of A is greater than cardinality of B, then there is no surjection from B onto A. Or any logically equivalent implication.   Formally,     card($A$) > card($B$) $\implies$ $\forall$ $f \in A^{B}$, $\exists$ $a  \in A$ : $\forall b \in B$,  $f(b) \neq a$.   It is my goal to avoid the use of the axiom of choice. Earlier I arrived at the equivalent implication     There exists a surjection from B onto A implies there exists an injection from A into B   But after defining the family of sets and failing to sufficiently arrive at the consequence I did some research and found that this statement does require the AC.  So I suppose my specific question is: can any logically equivalent statement be proven without the AC? Or is it just the direct proof of the second highlighted statement that requires AC?  Lastly, to be clear, the definition I am working with for card($A$) > card($B$) is there exists a set C that is a subset of A such that there is a bijection from $B$ onto $C$ but there is no bijection from $B$ into $A$  I will be on the computer for the next while and will be happy to post further information regarding my approaches and attempts if anyone wishes. Also I read through all the information here  regarding cardinals with and w/o AC and still couldn't deduce an answer.

I stumbled across this  earlier, and the top comment on the bottom answer asserts two claims: Without the Axiom of Choice,    It is consistent that there exists a function with domain $\mathbb{R}$ whose range has cardinality strictly larger than that of $\mathbb{R}$. It is consistent that there exist surjective maps $X\to Y$ but $|X|$ and $|Y|$ are incomparable.   I haven't studied set theory in years, but I find both these claims surprising and intriguing. I couldn't find any mention or proof of these facts online. Does anybody have a proof or reference to either of these? Thanks.


How can i enlarge icon in browse menu? When i want to upload some pictures to sites, and when a window opens for finding and selection images, icons are to small, i need to enlarge them so i can see pictures right away (dont want to click on every one to see preview). See image attached.

I have google chrome and when I upload photos to Facebook or Imageshack I cannot find a way to show thumbnails, only detail view. I also tried this in Firefox. This is quite important as it is stopping my friend from switching to Ubuntu over Windows.  Included a picture of the File Upload window, how do I  change this to a thumbnail view rather than the current list?


Okay, I'm still a bit confused as to this Training/Validation/Test Set split. I might be wrong here, but from what I understand, the model is first applied to the Training set, to "learn" from it and figure out the parameters to be used. Then comes the Validation set, and this is where I'm confused. I've read that the validation set is used for Hyperparameter tuning, to figure out which value of hyperparameter would be appropriate to use in the model. (After which, you can then apply and assess your final model on the test set.) Now let's suppose the model I'm applying is a Lasso or Logistic Regression, and the hyperparameter I'm tuning is Lambda. Or the model could even be, say, a Polynomial SVM, and the hyperparameters I'm adjusting is Degree and C.   My question is, as I'm tuning/adjusting these hyperparameters, wouldn't the value of my parameters change in the process? For example, for a Lasso Regression, the lambda is used as a weight to restrict the coefficients from getting too large. Therefore as I adjust lambda, the coefficient values change. Therefore what was the point of initially fitting the model to the training set in the first place?

In general, if we have a large dataset, we can split it into (1) training, (2) validation, and (3) test. We use validation to identify the best hyperparameters in cross validation (e.g., C in SVM) and then we train the model using the best hyperparameters with the training set and apply the trained model to the test to get the performance.  If we have a small dataset, we cannot create training and test set (not enough samples). Therefore, we will do cross validation (k-fold, leave-one-out, etc) to evaluate the model performance.  I have seen nested cross validation (whether repeated or stratified) has been used in the setting of small dataset, i.e., to generate generalized model performance while optimizing parameters selection. My question is, how can I obtain the best hyperparameters in nested cross validation (repeated/no repeated)?  I am interested in doing this in scikit-learn, if possible. I am a bit confused about how to do it.  I have read several resources but none gave me the definitive answer for this question:


The new top bar looks like a good improvement, but I think that at least the log out button and also the chat could return to a more prevalent place. Another thing that bothers me is that the quick link to privileges seems to have been removed. I kind of liked clicking on myself in the bar to see my recent reputation and such, although the new reputation looks cool. It does however get confusing with other sites being mixed in.  I'm sure we will all adapt to it pretty quickly, but please consider changing the position of some links, like moving chat, blog, and log out back to the bar itself. Thanks!

In the previous version the logout button is under your username, which it can be found by clicking the down arrow. However, in the new version, after a couple minutes of searching, it is under the "site-switcher" button:        This is really illogical since the logout button is usually under your username, including Google and Yahoo! services.  I suggest bringing back the  which will definitely benefit new users and even old users.


I wonder if it is possible to choose which layers would be visible in the Overview Map loaded in the Map Composer. Note that this is already possible for the Overview Panel in the QGIS Desktop: for each of the layer in your Map you can right-click on the name and check the "Show in Overview" (see image below).    But if I insert an Overview Map in the Map Composer I've no control on the layer's visibility: so all the layers (vectors and rasters) that are visible in the reference Map Frame will be also visible in the Overview Map (see image below).    I'm currently working with QGIS 2.14 Essen.

The title pretty much says it all.  I have a base map in QGIS that I am using with several Print Composers.  In one of the Print Composers, I don't want one of the layers to show up.  Is there any way to accomplish this?


maybe title is not correctly describing what I want to achieve, so here is an example:  I have a code where I call this:  object.AddProvider<definition, implementation>()   method description is:  public void AddProvider<TDefinition, TImplementation>()             where TDefinition: class             where TImplementation : class, TDefinition, IDataProvider   I have configuration where I define 'definition' (interface) and 'implementation'     "Interface": "MyAssembly.Abstractions.IMongoDataProvider,   MyAssembly.Abstractions" "Implementation":   "MyAssembly.DataProviders.MongoDataProvider, MyAssembly.DataProviders"   Then I call this to get types from the configuration:  var definition = System.Type.GetType(@"{Interface}", true, true); var implementation = System.Type.GetType(@"{Implementation}", true, true);   But I am not able to do this  object.AddProvider<definition, implementation>()   I don't know how to fulfill method's criteria (what to do between last two examples codes). Can anybody help me please?

What's the best way to call a generic method when the type parameter isn't known at compile time, but instead is obtained dynamically at runtime?  Consider the following sample code - inside the Example() method, what's the most concise way to invoke GenericMethod<T>() using the Type stored in the myType variable?  public class Sample {     public void Example(string typeName)     {         Type myType = FindType(typeName);          // What goes here to call GenericMethod<T>()?         GenericMethod<myType>(); // This doesn't work          // What changes to call StaticMethod<T>()?         Sample.StaticMethod<myType>(); // This also doesn't work     }      public void GenericMethod<T>()     {         // ...     }      public static void StaticMethod<T>()     {         //...     } }


I have three classes.  Person <-- Student <-- GradStudent, where <-- means extends (ie, GradStudent extends Student, Student extends Person)  Person person = new Student(); // this is perfectly legal  GradStudent gradStudent = (GradStudent) person; System.out.println(gradStudent); // java.lang.ClassCastException here   Why? Our person variable is a Student, and we could do Student s = new GradStudent(), and so why is this not working?  Similarly if I do  Student student = new Student(); GradStudent aGradStudent = (GradStudent) student; System.out.println(aGradStudent); // same error here   Why can we do Student s = new GradStudent(), but we cannot do Student student = new Student(), and THEN GradStudent aGradeStudent  = (GradStudent) student

Upcasting is allowed in Java, however downcasting gives a compile error.   The compile error can be removed by adding a cast but would anyway break at the runtime.   In this case why Java allows downcasting if it cannot be executed at the runtime? Is there any practical use for this concept?   public class demo {   public static void main(String a[]) {       B b = (B) new A(); // compiles with the cast,                           // but runtime exception - java.lang.ClassCastException   } }  class A {   public void draw() {     System.out.println("1");   }    public void draw1() {     System.out.println("2");   } }  class B extends A {   public void draw() {     System.out.println("3");   }   public void draw2() {     System.out.println("4");   } }


I'm having so much problem calculating the area, can anyone help?

From a square of unit length, pieces from the corners are removed to form a regular octagon. Find the value of the  removed area.  I got a weird answer, as I considered each side of the removed area will be $\dfrac{1}{3}$ and got $\dfrac{1}{18}$ for area of one triangle. Then I multiplied it by 4, to obtain  $\dfrac{2}{9}$ which I thought to be the answer but I was wrong.


Yesterday i updated my 12.04 to 14.04 which went very well except some smaller issues.  Today is installed the nvidia package 337 (through the additional drivers app) and rebooted, everything was just fine.  After some hours and several reboots (everything was fine until now), i thought to update from the older kernel version 3.5, wich was still installed and active from 12.04, to the actual kernel version 3.13le also. The update itself went well but after that i was stucked at bootsplash and i got an errormessage that the UUID is not yet ready.   Okay i got my LiveCD and repaired the grub installation. After that i was able to boot to the login screen. I was happy and tried to login but keyboard and mouse was gone.   I rebooted now several times, blacklisted driver, enabled blacklisted ones for usbkbrd and usbmouse but no way. At the moment i reach the bootsplash my keyboard/mouse are gone.  Im not able to log in and im also not able to start a command line. The recoverymode is exactly the same. Im happy to have CentOS also installed so i can access the system.  Xorg.0.log shows errros about the nvidia driver is not found. All .conf files depending from the nvidia installation in /etc/modprobe.d/modules are broken. I was just wondering why because i already used the nvidia driver yesterday on the old kernel. The Problems occurs after the kernel update.  For me it seems that the kernelupdate brings that lucky situation :-)  Any hints are welcome. Is there anything an could do from Centos?  I will now try to blacklist all my roccat hardware which i had also installed and see how that works.  EDIT The network is also disabled from what i can say here

I was trying to delete old kernels, but I must have deleted all of the kernels on my Ubuntu 11.04 laptop. Is there any way to fix this via USB boot or mounting hard drive on another system?


I searched for a lot of answers here but i still have a problem with the UTF8. "Special" letters doesn't appear in my browser.  I'm using:  php Designer 8 Wampserver 3.1.4_x86 MySQL 5.6 Navicat100_premium I'm using Google  [ those "?" are all "çççççççç"  This is the beginning of the code:    <html> <title> APPACDM </title> <meta name="viewport" content="width=device-width, initial-scale=1"/> <link rel="stylesheet" href="https://www.w3schools.com/w3css/4/w3.css"/> <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css"/> header('Content-type: text/html; charset=utf-8'); <head>     <meta http-equiv="Content-type" content="text/html; charset=utf-8" />     <meta name="viewport" content="width=device-width, initial-scale=1">

I'm setting up a new server and want to support UTF-8 fully in my web application. I have tried this in the past on existing servers and always seem to end up having to fall back to ISO-8859-1.  Where exactly do I need to set the encoding/charsets? I'm aware that I need to configure Apache, MySQL, and PHP to do this — is there some standard checklist I can follow, or perhaps troubleshoot where the mismatches occur?  This is for a new Linux server, running MySQL 5, PHP, 5 and Apache 2.


What are the several known and unknown closing costs associated while purchasing a house in USA? How can we significantly reduce closing costs ?

I see a lot of help online for calculating the actual cost of buying a house - this includes things like down payments, calculating the monthly payments and interest rate, the real utility cost of owning a home, pretty much everything that goes into the actual purchase price and upkeep cost. That's not what I'm interested in though. What I'm interested in knowing is the less talked about cost of the process of buying a house - the closing cost, the cost of hiring a real estate agent, the cost of the inspection prior to buying, all the things that add up before the purchase even takes place. In short, what is a normal range of cost for the purchase of a new home? For a couple of assumptions to work off of:  Assume my new home is in the range of $180,000 - $250,000 with a 5% down payment Also assume that I do hire a real estate agent Assume that I will be hiring an inspector for the entire property of the house Assume that I have agreed to cover closing costs BUT, if any of these costs are things that 'the seller would usually cover', then telling me that would be considered an acceptable part of your answer, so long as the actual cost of it is still included. Finally, moving costs should also be included - even though I know that's a normal cost for moving out.  The reason for this is - my wife and I are saving up for our first home purchase, and we're looking to go on the hunt next year. Since there are plenty of resources for the actual cost of the home itself, I'd like to know what the expected expenses will be for costs outside of the actual price of the home. My specific circumstances are most likely to be - living in New York State, planning to move to the state of Maryland (to help support her parents as they grow older) and either rent for an additional year to save up, or buy a new place outright when we move down - so moving costs should also be included.


This is used in Categories for the Working Mathematician to introduce two opposing functors U,V between the category of sets and the category of K-vector spaces, where K is a field. Can this be done in a LaTeX code that renders on MSE?

How can I label $\rightleftarrows$ above the top arrow and below the bottom arrow?


In various shell scripts I often see two approaches for getting information from databases supported by Name Service Switch libraries like /etc/group, /etc/hosts or /etc/services. One is getent utility and other is grep or some other text processing tool. For example:  root@fw-test:~# getent passwd root root:x:0:0:root:/root:/bin/bash root@fw-test:~#    root@fw-test:~# grep root /etc/passwd root:x:0:0:root:/root:/bin/bash root@fw-test:~#    ..or:  root@fw-test:~# getent hosts www.blah.com 189.113.174.199 www.blah.com root@fw-test:~#   root@fw-test:~# host www.blah.com www.blah.com has address 189.113.174.199 root@fw-test:~#    Which of those two approaches above should be used in scripts? I mean is one of the solutions more elegant or standard than the other?


I want to have a table under a subsection, but the place I write the table and its specifications in the source file seem not to matter. Can someone explain how to have a table at a desired position together with its vertical and horizontal position?  Thanks  Edit: The part of the code I mention is as follows:  \documentclass[12pt]{article} \usepackage{a4, color} \usepackage{amsmath, amsfonts, amssymb} \usepackage{siunitx} \begin{document}  \title{Understanding Semiconductor Lasers} \author{Ongun Ar\i sev} \date{Report: 15.10.2013\\ Experiment: 8.10.2013} \maketitle \subsection{Output characteristic of semiconductor laser diode}  \begin{table}[htbp] \centering \begin{minipage}[t]{.4\textwidth} \begin{tabular}[t]{|c|c|} \hline I\,(\si{\milli\ampere})&P\,(\si{\micro\watt})\\ \hline 2.5&0.53\\ 2.6&0.56\\  \hline \end{tabular} \end{minipage} \begin{minipage}[t]{.4\textwidth} \begin{tabular}[t]{|c|c|} \hline I\,(\si{\milli\ampere})&P\,(\si{\milli\watt})\\ \hline 11.0&12.63\    \hline \end{tabular} \end{minipage} \end{table} \newpage \subsection{Divergence angle of the beam measurement} \begin{table} \centering \begin{minipage}[t]{.4\textwidth} \begin{tabular}[t]{|c|c|} \hline I\,(\si{\milli\ampere})&P\,(\si{\micro\watt})\\ \hline  \hline \end{tabular} \end{minipage} \end{document}

Is there any package or a method to force LaTeX to keep floating environments like table and figure closer to where they are declared?


Good morning,  Can you give me a help to demonstrate this proposition:  $f$ is an even and continuous function on the interval $[-a,a], a>0$. Demonstrate:  $$\int_{-a}^a \frac{f(x)}{1+e^x} \,dx= \int_0^a f(x) \,dx$$

I have a question:     Suppose $f$ is continuous and even on $[-a,a]$, $a>0$ then prove that   $$\int\limits_{-a}^a \frac{f(x)}{1+e^{x}} \mathrm dx = \int\limits_0^a f(x) \mathrm dx$$   How can I do this? Don't know how to start.


Are commas below correct, please?  In the solution, we except  From the beginning, we search for

I am no native speaker and always confused about the comma in introductory phrases, in particular in prepositional phrases. Is there any hard rule when a comma must be set? If I make a google search for certain phrases, I often find both variants. Typical examples where I am not sure whether a comma must be set are:        First[ly][,] I must phone mother   In this case[,] we must...   For simple problems[,] the algorithm...   From Lemma 1.2[,] we obtain...   For a typical user[,] the algorithm...   In our theory[,] we...   A dark line on the horizon[,] the mountain range we were headed for seemed somehow not as threatening as when we had started out on the trip.   Avidly reading her novel[,] Jane did not notice that her stop was approaching.   To be sure[,] it is not easy to see a solution.   When you get to Rome[,] give me a ring.


I found the following in this forum:  \def\firstcircle{(0,0) circle (1.5cm)}    \def\secondcircle{(60:2.1cm) circle (1.5cm)}    \def\thirdcircle{(0:2.1cm) circle (1.5cm)}   My goal is to draw three circles with intersections. It works fine. But i do not know why. It's clear what the coordinate (0,0) in the definition of the first circle means.  But how can I interprete (60:2.1cm) or (0:2.1cm)?

\draw (0,0) -- (60:.75cm) arc (60:180:.75cm);   What does the colon in (60:.75cm) mean? Normally, I'd define a normal point there.


I'm trying to do a Blackjack game but I don't know how to change the value of "ACE" to 1 if 11 is too high. I'm now trying to search a Arraylist for A's to change the value of one ore more of them. But how can I see how much A's are in my Arraylist?        while (getPointsPC() < 17 || getPointsPC() < getPointsPL()){              int acees = 0;              random = bj.getRandom();             CardsPC.add(bj.getCard(random));             setPointsPC(random);              lblPointsPC.setText("Points Dealer: " + Integer.toString(getPointsPC()));              String text = CardsPC.get(0);             for(int i = 1; i < CardsPC.size(); i++){                 text = text + ", " + CardsPC.get(i);             }              if (CardsPC.contains("A") && getPointsPC() > 21 && acees < CardsPC.**HOW_MUCH_A's???**){                 setPointsPC(13);                 acees++;             }              lblCardsPC.setText(text);          }

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.


^ I've got those beautiful cubes to run a physiks simulation, but obviously they are one object so I they can't move independently. I want each of them to be a single object. Is it possible to split all of them simultaneously?

I've just made a set of armor by using a male body mesh model I downloaded and selecting certain faces from the model and duplicating them to create viable armor pieces.   Since the pieces are just duplicated from the same mesh male model, then it's still part of the same object.   How do I separate the armor piece from the model to make the pieces separate?


I want to know what the following code means and what each of a, b, and c become:  def addit(a,b,*c):      return a+b+sum(c)      addit(3,5,15,21,5)

In the following method definitions, what does the * and ** do for param2?  def foo(param1, *param2): def bar(param1, **param2):


How can I draw one of these Karnaugh maps using tixz? I would like to have q_x^+ in the corner.

I've been using LaTeX for a couple of years, but I'm pretty new to the tikz package. In particular, I'd like to add Karnaugh's maps in my document. I've already found a solution that satisfy me (can be found here: ), and I'd like to slightly adjust it to make the boolean params appear at the very first cell which I want it to be diagonally split like in this example: .  Would anybody help me? Thanks in advance!


I just saw a photo from NASA. This is it.    This is beautiful. But i am not being able to understand, what are those red and green lines above the earth surface? These cannot be due to Rayleigh scattering of course as there are no particles to do that.   Moreover, just above the surface of the earth, we see a blue colour( which is very faint ) . Is this due to Rayleigh scattering?   PS- I can assure you, that these are not photographic effects, so please don’t take it into account.

What could be the possible reason for the green border visible in this satellite image ?    ()


Let $A$ be a $n\times n$ matrix over $\mathbb{C}$. If $A^n$ = $I$ for some $n>0$, then how to show that $A$ can be diagonalized? The hint I have is to show that the characteristic polynomial has no repeated root.

Let $A$ be a complex matrix of size $n$ if for some positive integer $k$ , $A^k=I_n$ , then is $A$ diagonalizable ?


So I have a question where it says to find the last non zero digit of $20!$  I proceeded in the following way:  Found the prime factorization of $20!$ by calculation the greatest powers of $2,3,5,7,11,13,17,19$ in $20!$ using the following formula....for 2....as follows...  $$\left[\frac{20}{2}\right]+\left[\frac{20}{4}\right]+\left[\frac{20}{8}\right]+\left[\frac{20}{16}\right] = 18$$ and did the same for 3,5,7,9,11,13,17,19  This turned out to be $$20! = 2^{18}\times3^8\times5^4\times7^2\times11\times13\times17\times19$$  From here, multiplying in my head with just the unit digits gave me the answer that is, 4.  Is there any way to do it easier? I was able to do this as 20 is relatively small and it would have a max prime of 19, but what if, for example, the question was asked to find the last non zero digit in $77!$? Then this wouldn't be possible.   Any help would be appreciable

I ran into a cool trick for . This is actually a recurrent relation which states that:  If $D(N)$ denotes the last non zero digit of factorial, then   $$D(N)=4D\left(\left\lfloor{\frac N5}\right\rfloor\right)\cdot D(\mbox{Units digit of $N$})  \qquad \mbox{(If tens digit of $N$ is odd)}$$ $$D(N)=6D\left(\left\lfloor{\frac N5}\right\rfloor\right)\cdot D(\mbox{Units digit of $N$})  \qquad \mbox{(If tens digit of $N$ is even)}$$  Where $\left\lfloor\cdots\right\rfloor$ is greatest integer function.  I was wondering, if anybody could explain why this works?


I expected to find answers along the lines of quantum-computing insight into attacking AES; however, answers on this question aren't applicable because "Quantum computers give a quadratic speedup on a (sic) general search problems".  Let us suppose the very worst case: P=NP by constructive proof. Therefore, 3-SAT and direct polynomial attacks on AES and all other standard-model symmetric ciphers.  How do we construct something that takes a serious attack to break besides using ECB and sending one block per key? Do quantum-proof symmetric ciphers with properties other than those of the one-time pad actually exist?  I think I can prove that if you use any kind of MAC other than polynomial evaluation MAC (or something else with its characteristic deniability) your cipher must fail.  I can prove that ciphered random data is possible because you can't break ECB over random data, but that proof is useless.  I am aware of the implausibility of ending up in this world of P=NP. I am also aware of this old post describing very good reasons why P=?NP is a poor model for breakability. I am interested in this problem because I am reasonably certain that any solution must use an encryption method that is, of itself, deniable.  The one-time pad has this property; however, I'd rather have an answer that offers something less unwieldy, if possible.

From what I heard, many encryption algorithms are based on the assumption that some problems are computationally hard, i.e, NP-complete. In the unlikely event that someone proves that P=NP, these codes will break.  Is there a practical encryption algorithm that will remain safe even if P=NP? I.e, an algorithm that depends on problems that are more difficult than just NP-complete?  My guess is that the answer is no: to be practical, a code must be verified in polynomial time, i.e, the problem must be in NP. Is this correct?


Is it possible to think of something that does not contain anything that already exists? If not, why? Examples.   Flying alligators are animals. Flying straws are straws.   Is it possible for our thoughts to entirely base on objects that do not exist?

Descartes famously says "I think therefore I am." Does it follow that  anything I can think of exists?


In tex documents of mathematics, sometimes title of section involves some math symbols, such as   \section{Groups with $G'=Z(G)$}   However, using dollar sign in title of section always shows some warning.   What should be the way to write title of sections involving math symbols?

I have a section heading which includes an epsilon. Furthermore I am using the "hyperref" package to create links in my PDF document.  When compiling I get a strange warning that a math symbol is not allowed in a PDF string, e.g. Token not allowed in a PDF string (PDFDocEncoding): (hyperref) removing \varepsilon on input line 6.  However, if I open the compiled PDF there are no obvious errors and all links are clickable. Am I missing something, or can I just ignore this warning? Are there any alternatives to achieve the same result?  \documentclass{article} \usepackage{hyperref}  \begin{document} \tableofcontents \section{$\varepsilon$SOA}  Text about $\varepsilon$SOA.  \end{document}     Thanks in advance!


I still remember my Yahoo! ID and password but the problem is when I login, I'm asked to provide the security question which I already forgot the answer. I don't have any other recovery ways like "alternate email" or "phone number".  I tried also the answers from this  but seems to be not applicable to me or not working.  Is there any email we can send for support? Since hotline numbers are for UK & Canada only I think.

I have forgotten my Yahoo! Mail account password. What is the procedure to retrieve my password?  Note that I'm not asking where the link is. I want to learn about the procedure (i.e. if they ask me about my birthday, the secret question which I defined years ago, etc.).


I'm looking for a script/program which will display the top x largest directories/files and then descend into those folders and display the x largest directories/files for a configurable depth.  231MB bin  - 220MB ls   - 190MB dir   - 15MB def   - 3MB lpr  - 10MB asd  - 1MB link   How can I do that?

I was using df -h to print out human readable disk usage. I would like to figure out what is taking up so much space. For instance, is there a way to pipe this command so that it prints out files that are larger than 1GB in size? Other ideas?  Thanks


What I want to achieve is something similar to the following entity. Now I want data_(x)_i to be an array of std_logic_vector, with each individual length definable at component instantiation.  entity module_A is     port(         rst_i      : in  std_logic;         clk_i      : in  std_logic;         data_0_i   : in  std_logic_vector( 1 DOWNTO 0);         data_1_i   : in  std_logic_vector( 2 DOWNTO 0);         data_2_i   : in  std_logic_vector( 3 DOWNTO 0);         data_3_i   : in  std_logic_vector( 4 DOWNTO 0)     ); end entity module_A;   I tried the following code  utils.vhd:  package utils is     type int_array_t is array (integer range <>) of integer;     type data_array_t is array (integer range <>) of std_logic_vector;      function get_width (         int_array: int_array_t        ) return integer;  end package utils  package body utils is     function get_width(         int_array: int_array_t     ) return integer is     begin         for i in 0 to int_array'length-1 loop             return int_array(i);         end loop;     end function; end package body;   module_A.vhd:  entity module_A is     generic(         DATA_WIDTH : int_array_t := (2, 3, 4, 5)     );     port(         rst_i  : in  std_logic;         clk_i  : in  std_logic;         data_i : in data_array_t(DATA_WIDTH'range)(get_width(DATA_WIDTH)-1 DOWNTO 0)     ); end entity module_A;   Modelsim throws the following error      ** Error: D:/WORKSPACE/PERSO/HPD_ALT/RTL/RTL/pkg_utils.vhd(24): Parameter for attribute "left" must be locally static.   Is there a way to achieve what I want?

I'm writing a vhdl model and I'm stuck with a problem about port declaration. Let's say that I have an entity entityA that instantiates N entityB. Now, entityB has a port, out, with size M bits, and M can vary among all entities, so out is std_logic_vector(M-1 downto 0). These ports need to be propagated outsize entityB.  If all entityB components would have the same port size, say FIX_M, the solution would be to use a std_logic_vector(N*FIX_M-1 downto 0) in entityA. My problem is that the size M can vary. The first solution that comes to my mind is to use the same solution, using instead of M a MAX_M, but in that case a lot of pins would be left unused (and for input it is a problem, right?).   Do you have a better idea? Thank you in advance.


Just now I saw a user with a banner on his/her profile page that says the user is suspended until '18.  Right now, it is 2019.  The user should have been set free last year, but for some reason he/she still appears to be suspended with only 1 reputation.          Why is the user still appearing to be suspended?  It seems to be a kooky error to me.  Can anyone please try to fix this bug, or at least explain to me what is going on?  -

I came across a user with a notification that states:     This account is temporarily suspended network-wide. The suspension period ends on Dec 2 '18 at 2:35.   Screencap for posterity:    Unless this user is  (in which case the full year should be shown, or at least a tooltip), it seems like they should have been unbanned 4 months ago.


I'm trying to install CUDA and NVIDIA drivers to use a GeForce 1080 and a Titan XP GPU on my workstation.  However, running:  sudo apt-get install nvidia-driver-440   I got the following error, which I don't know how to solve:   Reading package lists...  Done   Building dependency tree          Reading state information... Done    Some packages could not be installed. This may mean that you have   requested an impossible  situation or if you are using the unstable  distribution that some  required packages have not yet been created or been moved out of  Incoming.  The following information may help to resolve the  situation:   The following packages have unmet dependencies:     nvidia-driver-440 : Depends: libnvidia-gl-440 (=  440.59-0ubuntu0.18.04.1) but  440.64.00-0ubuntu1 is to be installed                       Depends: libnvidia-compute-440 (= 440.59-0ubuntu0.18.04.1) but 440.64.00-0ubuntu1 is to be installed                       Depends: libnvidia-decode-440 (= 440.59-0ubuntu0.18.04.1) but it is not going to be installed                       Depends: libnvidia-encode-440 (= 440.59-0ubuntu0.18.04.1) but it is not going to be installed                       Depends: libnvidia-fbc1-440 (= 440.59-0ubuntu0.18.04.1) but 440.82-0ubuntu0~0.18.04.2 is to be installed                       Recommends: nvidia-settings but it is not going to be installed                       Recommends: nvidia-prime (= 0.8) but it is not going to be installed                       Recommends: libnvidia-compute-440:i386 (= 440.59-0ubuntu0.18.04.1) but it is not installable                       Recommends: libnvidia-decode-440:i386 (= 440.59-0ubuntu0.18.04.1) but it is not installable                       Recommends: libnvidia-encode-440:i386 (= 440.59-0ubuntu0.18.04.1) but it is not installable                       Recommends: libnvidia-ifr1-440:i386 (= 440.59-0ubuntu0.18.04.1) but it is not installable                       Recommends: libnvidia-fbc1-440:i386 (= 440.59-0ubuntu0.18.04.1) but it is not installable                       Recommends: libnvidia-gl-440:i386 (= 440.59-0ubuntu0.18.04.1) but it is not installable   E: Unable to correct problems, you have held broken packages.   Info on my OS (output of lsb_release -a):  No LSB modules are available. Distributor ID: Ubuntu Description:    Ubuntu 18.04.4 LTS Release:    18.04 Codename:   bionic   Any help? :)

After upgrading from 10.04 to 12.04 I am trying to install different packages.  For instance ia32-libs and skype (4.0).  When trying to install these, I am getting the 'Unable to correct problems, you have held broken packages' error message.   Output of commands:  sudo apt-get install -f Reading package lists... Done Building dependency tree        Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.   After running this:  sudo dpkg --configure -a foo@foo:~$ sudo apt-get install -f Reading package lists... Done Building dependency tree        Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.


I must be missing something obvious here. If there are two equally versioned RPM packages of the same software product, with one of them installed on one of my rigs (with a metric tonne of packages as dependencies), how can I replace it with another without going through the hassle of erasing and reinstalling an insane number of dependent packages?  I'd like to do it via yum. rpm-based solutions (with forcing) are grudgingly accepted.

Is there a way to add and remove packages at the same time with a single yum command? For example, installing postfix and removing sendmail without running two separate commands/transactions.


I recently bought a replacement battery for my Toshiba Equium L40-17M laptop. It is showing a 5400 mAh. Usually it seems this model takes a 4400mAh. Will the larger mAh damage my laptop?

I have an Acer Aspire 5536G. My battery is having problems so I am thinking of replacing it. I have searched online through many sites and I found some good deals. However, currently my laptop has a 4400mAh lithium ion battery so I was thinking of replacing it with 8800mAh 12-cell battery that lasts more hours than 4400mAh without power plug.


One time, I was writing an answer to a question, when the question was closed. I had spent a little time on the question, so I didn't want to lose it. The post button was disabled, so I inspected it and saw that there was a single attribute disabling it: disabled = "disabled"  I undid it, and was able to post my answer, even though the question was closed. There was no JS to keep me from posting it. Is this intentional, or just a mistake that the developers never thought about?

Question:   Answer:   The question was closed at 11:57:57 (according to the hover-over-"x-mins-ago" bar) and the answer was posted at 12:16:35. It's a fairly lengthy answer, so it's possible that it was started to be written before it was closed but I swear I've started to answer a question then I got a banner along the top saying "this question has been closed" and the answer was no longer post-able.


I have multiple foreach loops in my program which I want to break one of the inner loops at a certain met condition.  I know in Java you can give it some sort of label, and then when the condition is met you write break LabelName  Is there something similar to it in C#? I read there was something goto but goto is pointing to go somewhere to continue performing methods rather than just breaking the loop.  Sample code in Java:  STOPLOOP : for(Clause c : clausesList)             {                 // Random Coding                             if(!l.solved(hasExcl))                             {                                 literalCanBeRemoved = false;                                 c.complete = false;                                 break STOPLOOP                              }

If I have a for loop which is nested within another, how can I efficiently come out of both loops (inner and outer) in the quickest possible way?  I don't want to have to use a boolean and then have to say go to another method, but rather just to execute the first line of code after the outer loop.  What is a quick and nice way of going about this?  I was thinking that exceptions aren't cheap/should only be thrown in a truly exceptional condition etc. Hence I don't think this solution would be good from a performance perspective.  I don't feel it it is right to take advantage of the newer features in .NET (anon methods) to do something which is pretty fundamental.


Currently my command line prompt looks like this nuve@nuve-Inspiron-5547:~$ but I want to change it Azer's Terminal:"Path of current directory". How can I do this? I need exact code line to add to bashrc file.

Currently it is:   michael@Castle2012-Ubuntu-laptop01:~/Dropnot/webs/rails_v3/linker/spec/controllers$   Outside of renaming my machine and directory structure...  How could I make it be something more like:  michael:controllers$


I am running the macOS Big Sur Beta. Every little while, iCloud Drive will randomly start to download 50GB of files I don't need. I have a ~40GB zip file full of photos that I do not need stored on my laptop and this keeps downloading. This is wasting a lot of data. How can I fix this?

I have enabled storing Desktop & Document Folders in iCloud. I keep my Xcode projects on Desktop. Every hour or so, iCloud will store files, inside of Pods folder present alongside the Xcode Project in iCloud. This is very tedious as I then have to click on each one of them one-by-one to re-download.  How can I prevent iCloud from downloading my files in this manner, for this specific Xcode project?  I have tried disabling iCloud for Desktop, but this results in me losing all my Desktop folders/files, so I could rather not go this route.


I'm planning to put a window air conditioner in an apartment awning window. The window part that swings open cannot be removed so,the exhaust from the air conditioner would be blowing against the window. Would the exhaust be very hot and,if so could it cause damage to the window parts? Any suggestions?

I bought a window air conditioner thinking that I could alter my awning window to accommodate it. I have since discovered that I can't remove the part of the window that swings out or alter it so that it swings out farther. Has anyone found a solution to this, besides using a portable air conditioner, which I don't want to do?  I have thought of building a wooden enclosure for the air conditioner connected to and sealed with the window opening. In other words, a window extension. I would be concerned about a possible fire hazard because of the air (hot?) exhaust and if the exhaust would affect the material that the window is made of.


Below is the example -   I'm going to ??Location??. I will go to ??Location_New??  In these string values I need to capture the text surrounded by ?? mark. I can replace it if the values within the ?? mark is static using contains method. However it is not but I need to capture the text. So can you someone guide me on this.  Application purpose is, It should capture any values surrounded by ?? mark and prompt to user then user will enter the value that should replace the text surrounded by ?? mark. Not just one text value only. All the text surrounded with ?? mark

I have a string User name (sales) and I want to extract the text between the brackets, how would I do this?   I suspect sub-string but I can't work out how to read until the closing bracket, the length of text will vary.


$\textbf{Question:}$Find all positive integers $a, b$ such that the expression $$\frac{a^2+b^2+1}{ab-1}$$ is an integer. $$$$As the expression is symmetric in $a, b$, so let $a \geq b$. It is easy to check the cases when $a=b+k$ where $0 \leq k \leq 2$, so let $a \geq b+3$. Suppose $a, b$ satisfies the given condition with $a+b$ minimized. Let us write $$\frac{a^2+b^2+1}{ab-1}=k$$ then our equation becomes $$a^2-kab+b^2+k+1=0$$. Now this equation has a root $a$ and from the Viet's formula we get the second root $$a'=kb-a$$ and $$a'=\frac{b^2+k+1}{a}$$. Now the first equation shows that $a'$ is an integer and the second equation shows that $a'$ is a positive integer. Now to show that $a' < a$ we have to prove that $$a'=\frac{b^2+k+1}{a} < a$$. Now consider $$a^2-(b^2+k+1)=a^2-b^2-1-k=a^2-b^2-1-(\frac{a^2+b^2+1}{ab-1})=\frac{a^3b-ab^3-ab-a^2+b^2+1-(a^2+b^2+1)}{ab-1}=\frac{a(a^2b-b^3-b-2a)}{ab-1}$$. Now as $a \geq b+3$ so we have $$a^2b-2a=a(ab-2) \geq a((b+3)(b)-2)=a(b^2+3b-2) \geq a(b^2+1) > b(b^2+1) > b^3+b$$ and hence we get $\frac{a(a^2b-b^3-b-2a)}{ab-1}>0$ and hence we have $a' < a$ and hence $a'+b < a+b$ contradicting the minimality of $a+b$. So there are no solutions. $$$$Is My Proof Correct??

Determine all possible values of $\frac{a^2+b^2+1}{ab-1}$ where $a,b$ are positive integers.  I am quite certain one should use a Vieta jumping argument, but I cannot complete it.  Let $\frac{a^2+b^2+1}{ab-1} = k \in \mathbb{Z}$ with $a+b$ being minimal. Clearly $k > 0$ and we have $a^2 - kab + b^2 + k + 1 = 0$. Without loss of generality $a\geq b$. We see that $x_1 = a$ and $x_2 = kb-a = \frac{b^2+k+1}{a}$ are the roots of $x^2 - kbx + b^2 + k + 1 = 0$. The expression $kb-a$ shows they are both integers and $\frac{b^2+k+1}{a}$ they are both positive. To reach a contradiction, it suffices to have $b + \frac{b^2+k+1}{a} < a + b$, i.e. $b^2 + k + 1 < a^2$. Hmm, if we can perhaps somehow assure $k\leq a$, we will just consider pairs $(a,b)$ with $a\neq b$ and $a+b$ minimal $-$ that's how we can rule out the case $a\neq b$ and the rest will be very easy. So any idea how to complete this argument, if it indeed works?  Any help appreciated!


I currently have the second-highest rep on , which just went public beta.   says, "You need at least 1k reputation to review suggested edits."  Presently only one user has that much rep.  But the queue shows that users with less than 100 rep are reviewing suggested edits.  What is going on?

When clicking "edit" I see:  Your edit will be placed in a queue until it is peer reviewed. We welcome edits that make the post easier to understand and more valuable for readers. Because community members review edits, please try to make the post substantially better than how you found it, for example, by fixing grammar or adding additional resources and hyperlinks.  Like:     Likewise, when I am not logged in, clicking "improve this question" or "improve this answer" shows:  You are not . Your edit will be placed in a queue until it is .  And when I click 'Save', I get:  Thanks for submitting an edit. It is only visible to you until it's been approved by trusted community members  Like:     Who can suggest an edit? Where do suggested edits go? Who can vote on a suggested edit? How do suggested edits get reviewed? Can I earn reputation? What about abuse or bad edits? Sometimes the Community user approves or rejects my edit. Why is that? When can I not suggest an edit? Is there a minimum change requirement for a suggested edit? How do I check my suggested edit history? I disagree with the reasons why my suggested edit was rejected. What can I do? How do I know whether there are edits waiting for review? Someone suggested an edit to my own post, and the reviewers took the wrong action. What can I do? Are tag wikis included in this scheme? What do the "Improve Edit" and "Reject and Edit" buttons do? Why are apparently valid links to rejected edits resulting in 404 errors?   For more information about editing, see "" in the .


Assume I want to find the number of ways that a set with $n$ distinct elements can be partitioned into $k$ nonempty subsets, I know this is given by $ n\brace k$, But what is wrong with the following argument: $$\frac{1}{k!}\sum_{r_{1}+...+r_{k}=n}^{ }\binom{n}{r_1}\binom{n-r_1}{r_2}\cdot\cdot\cdot\binom{n-...-r_{k-1}}{r_k}\tag{$r_{i}\ge1$}$$$$\frac{1}{k!}\sum_{r_{1}+...+r_{k}=n}^{ }\frac{n!}{r_{1}!r_{2}!\cdot\cdot\cdot r_{k}!}\tag{$r_{i}\ge1$}$$ Which means choose $r_1$ of the $n$ elements to be contained in the first subset (cell of the partition) and so on till we need to choose $r_k$ elements from the $n−...−r_{k−1}$ elements to put them into the $k$th subset, on the other hand, this gives a permutation of the subsets and we need to divide by $k!$, since the cells of a partition are all identical. Why this does not give the number of such partitioning?

I have seen some recursive formulas for Stirling I and II kind but I am especially interested in explicit formulas.  I was thinking and get: $$ \left\{ {m \atop n} \right\} =  \sum_{k_i>0 \wedge k_1+k_2+...+k_n = m} \frac{m!}{n!}\cdot \frac{1}{k_1! \cdot k_2! \cdot ... \cdot k_n!}$$ I am not sure if it is ok but supposedly it is (I created it with combinatorics interpretation)  Can somebody look at that and tell me if it is ok/wrong?  By the way,if you have some nice formulas, I will be grateful for sharing that.


We have meter in the  - we use that to measure length. Other length units like light years can be expressed in meters. But how often do we express amounts or quantities in moles? Mole is a number of things, nut we do not define 1 in terms of mole, or a dozen, or a million. I have never seen anyone stating that a coil has $500/N_A$ moles of turns. It seems that we define none of the everyday counting units in moles.  However, it is included in SI, and it is even proposed to be included in . Why not just use 1 if we need the reference amount for the system of counting units, and make mole a derived or a non-SI unit used in SI (like liter)?  Inspired by

I am starting to study physics in detail and as I read about physical quantities, I was puzzled why mol (amount of substance) is taken as a physical quantity.  A physical quantity is any quantity which we can measure and has a unit associated with it. But a mol represents the amount of substance by telling the number of particles (atoms, molecules, ions, etc.) present. So it is a pure number and numbers are dimensionless. So mol should not be considered a physical quantity.  Also, fundamental physical quantities should be independent of each other. I am wondering whether mass and mol are independent. This is so as they surely affect each other as we can evidently see while calculating the number of moles and using the mass of that sample for calculation.  So how is the mol a fundamental physical quantity and independent of mass?


I installed VLC player using .  I don't know how to access other users, but root itself only, so I don't know if the video is outdated or works at all, anyway can I install VLC on root and run it from root as well?

I have installed a vlc in centos 6.5. I want to run it as root. But I get the following error,      "VLC is not supposed to be run as root. Sorry. If you need to use   real-time priorities and/or privileged TCP ports you can use   vlc-wrapper (make sure it is Set-UID root and cannot be run by   non-trusted users first)."


At the start of The Fellowship of the Ring Gandalf catches Sam eavesdropping on the conversation between him and Frodo about the true nature of the ring. Then Sam panics and pleas to Frodo:     ‘Mr. Frodo, sir!’ cried Sam quaking. ‘Don’t let him hurt me, sir!   Don’t let him turn me into anything unnatural! My old dad would take   on so. I meant no harm, on my honour, sir!’   Can Gandalf really do such a thing or is Sam just plain enough to believe that wizards are almighty?

Gandalf is a wizard. He is also the Tolkien equivalent of a mortal angel (if I understand what the Maiar are correctly.) What are his powers though? Specifically what magics does he use in The Hobbit and The Lord of the Rings? I assume he is a great and powerful wizard but I can't think of a single magical thing that he does that sticks out in my mind as showing his great power. He does fight a Balrog but it's a completely unseen battle. His wand glows and he speaks to eagles and telepathically with elves but that seems like minor magic to me. Grey or White what has he done?  Edit: Adding a link to a previous question that addresses specific uses of power.


I'm getting tired of reloading new systems on my ancient laptop. I started with Mint, then went to Ubuntu 15.04. Will I be able to go directly to the next long term release (and rest a little)?

I want to know where I can find updated information about all the stable and in-development versions of Ubuntu, where I can find this information?     This question is meant to be a canonical question. It expects to answer the following questions:         Is X version stable yet?   Is X version in beta?   Is X version still supported?   What versions are still supported?   What are the versions in Beta/Alpha?   Until where X version will be supported?   Have X version ceased support?   When will be X version released?   Where I can download any release?   When will the next LTS version of Ubuntu be released?         The list is not exhaustive.


Background  Hooray! Pi DAYYY! What I am trying to do is place random dots on a screen. The gui opens in screen state 0 and when I press 1 the screen state changes to screen state 1 which then should theoretically add random dots onto the screen. However, It doesn't work.  The problem  So if you look at the line "dotz.add(new Dot());" the compiler flagged that as a nullpointer exception but I wasn't sure why that was since i'm passing the Dot object  main controller code here-   package piday;  import java.awt.Color; import java.awt.Font; import java.awt.Graphics2D; import java.util.ArrayList;  import com.sun.glass.events.KeyEvent;  public class controllah extends GameDriverV4 {     int state = 0;     Font font = new Font("Helvetica Neue", Font.BOLD,50);     Dot Dot = new Dot();     ArrayList<Dot> dotz;     int time = 0;     int delay = 50000;     public controllah() {      }      public static void main(String[] args) {         controllah h = new controllah();         h.start();     }       public void draw(Graphics2D win) {         if (state == 0) {             win.setColor(Color.BLACK);             win.drawString("'MONTE CARLO'", 10, 200);             win.drawString("'PRESS 1'", 10, 200+font.getSize()+10);             if (GameDriverV4.Keys[KeyEvent.VK_1]) {                 state = 1;             }             win.drawString("'Needle Thing'", 10, 200+font.getSize()+10+50);             win.drawString("'PRESS 2'", 10, 200+font.getSize()+10+50+15);             if(GameDriverV4.Keys[KeyEvent.VK_2]) {                 state = 2;             }         }           if (state == 1) {             /*             if (time>delay) {                  time = 0;             }             else {                 time ++;             }             */              dotz.add(new Dot());             for (int i = 0; i<dotz.size()-1; i++) {                 dotz.get(i).draw(win);             }          }          if (state == 2) {          }      } }   Dot object code here-   package piday;  import java.awt.Color; import java.awt.Graphics2D; import java.awt.Rectangle; import java.util.Random;  public class Dot {     Color incolor = Color.BLACK;     Color outcolor = Color.BLUE;     boolean in = true;     int x;     int y;     public Dot() {         Random rand = new Random();         this.x = rand.nextInt(800);         this.y = rand.nextInt(800);     }       public void draw(Graphics2D g) {         if (in) {             g.setColor(incolor);         }         else {             g.setColor(outcolor);         }          g.fillRect(x-1, y-1, 3, 3);      }  }   I reasoned that since I've been trying to add a new "Dot" object into the arraylist "dotz" that it would be fine since the new "Dot" is not a null object

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


First I'd like to clear out that I know what a NullPointerException is and how to handle that. My question is about how to access the @ApplicationScoped bean that is created on server startup, through the scheduler that I would like to run once a day. All I get now is a new bean, which is null at the beginning and not the already created bean. The scheduler does the initiation of the bean so I end up with two beans, one that is updated by the scheduler (all the time) and one that is used when navigating in the web application.  So...  I have a web application with a @ApplicationScoped bean. This one is loaded from database on Tomcat startup. This means that if something is changed in database in some other way than through the web application the changes won't be viewable until the Tomcat has been restarted. So I thought I could make a Schedule to reload this @ApplicationScoped bean on a specific time during the day. The trouble is that I get a whole new @ApplicationScoped bean. So how should I do to get the current bean updated and not a new one?  I've tried the solution in this tread:  without any luck. My bean is still null.  I've also looked at the following threads without really solving my problem:      My ApplicationBean.java  import javax.enterprise.context.ApplicationScoped;  @Named(value = "applicationBean") @ApplicationScoped public class ApplicationBean {     @PostConstruct     public void init() {         //load variables from db     } }   My ScheduleTaskConfig.java  @WebListener public class ScheduleTaskConfig implements ServletContextListener {      private ScheduledExecutorService scheduler;      @Override     public void contextInitialized(ServletContextEvent event) {         Reloader reloader = new Reloader(event.getServletContext());         scheduler = Executors.newSingleThreadScheduledExecutor();         scheduler.scheduleAtFixedRate(reloader, 2, 3, TimeUnit.MINUTES);     }      @Override     public void contextDestroyed(ServletContextEvent sce) {         scheduler.shutdownNow();     } }   My Reloader.java  public class Reloader implements Runnable {      private ServletContext context;      public Reloader(ServletContext context) {         this.context = context;     }      @Override     public void run() {         ApplicationBean applicationBean = (ApplicationBean) context.getAttribute("applicationBean");         if (applicationBean != null) {             applicationBean.init();         }     } }   I just don't know what is wrong. I don't understand how to solve this.  I know I've written that the schedule should run every 3 minutes but when I get this to work the schedule should run once a day.  Is there a better way to do this or have I just forgotten something? I've googled the whole day without getting forward so I really need help. Thank you.  Edited: So my servlet context is up and my listener is notified before my application context is up?  What if I use the webpage then my application context is up (?) but my scheduler still doesn't work, the bean in the scheduler is still a new one and not the one I've been using when navigating in the web application. Or am I just confused over this? :) Thank you for your help.  Edited: I'm using Primefaces 6.0 and I suppose this bean is a JSF bean. Other beans used are Spring beans imported from a model class. Sorry for the confusion I have removed the Spring notation and added Primefaces instead. I hope this clears things out. Thank you


I'm attempting to rename a field in a shapefile. I select the layer, enabling editing and then apply changes, and save them. When I open the file again, it's been renamed 'field_to__1'. However this only seems to happen for certain (joined?) fields.  How can I save the field name changes in QGIS?

I would like to rename some fields in my attribute table:  Like rename "XRF_N3"in something else. It seems quite a easy issue but I don't find any information about how can I do that.


How can I have textHelp next to the Find button as shown below.   here is my Visualforce page source:

           Search:	           <apex:inputText style="width:100%" value="{!SearchText}" />	                        &nbsp;             <apex:actionStatus id="SearchIcon">               <apex:facet name="start">                 <apex:outputPanel >                   <apex:commandButton style="float: left;" disabled="true" value="Find" />                                    </apex:outputPanel>               </apex:facet>               <apex:facet name="stop">                 <apex:outputPanel >                   <apex:commandButton action="{!Find}" value="Find" rerender="BoxPanel" status="SearchIcon" />                 </apex:outputPanel>               </apex:facet>             </apex:actionStatus>

I have a Visualforce page which consists of questions and inputFields below the question .I want to use Help Text for that field so as to display the Text in place of question.How do i achieve it without using <apex:pageBlockSectionItem> ? My code:  <apex:pageBlock >    <apex:pageBlockSection >       <div class="questions">          <apex:pageBlockSectionItem helptext="{!$ObjectType.Survey__c.Fields.Impact_of_visit__c.InlineHelpText}">             {!$ObjectType.Survey__c.Fields.Impact_of_visit__c.label}              <apex:outputLabel value="{!$ObjectType.Survey__c.Fields.Impact_of_visit__c.Label}" />              <apex:inputField value="{!decision.Impact_of_visit__c}" />          </apex:pageBlockSectionItem>       </div>   </apex:pageBlockSection> </apex:pageBlock>   Its that i have to display 5 questions from the help text of the particular field.And if i use it in <apex:pageBlockSectionItem> ,i get blocks in the page which i dont want to display on the page.


I have been trying to get pdfLaTeX, Beamer, and PSTricks to be friendly. The following code compiles without hiccup, and a pics.pdf file containing my diagram is created, but the output presentation is completely blank.  \documentclass{beamer} \usepackage[pdf]{pstricks} \begin{document} \begin{frame} \begin{pspicture}(1,1) \psline(0,0)(1,1) \end{pspicture} \end{frame} \end{document}   Thanks in advance for your help.

\documentclass{beamer}  %\usepackage{pstricks,auto-pst-pdf} % works \usepackage[pdf]{pstricks} \usepackage{pst-tree}  \begin{document} \begin{frame}{Test}     \begin{postscript}         $\pstree{\TR{S}}{}$     \end{postscript} \end{frame} \end{document}   I get the following error:  Error: /typecheck in --div-- Operand stack:    1   0   0.0   -0.00706883   a   65781.8 Execution stack:    %interp_exit   .runexec2   --nostringval--   --nostringval--   --nostringval--   2   %stopped_push   --nostringval--   --nostri ngval--   --nostringval--   false   1   %stopped_push   1926   1   3   %oparray_pop   1925   1   3   %oparray_pop   1909   1   3  %oparray_pop   1803   1   3   %oparray_pop   --nostringval--   %errorexec_pop   .runexec2   --nostringval--   --nostringval--   - -nostringval--   2   %stopped_push   --nostringval--   --nostringval--   --nostringval--   --nostringval--   4   --nostringval--  %repeat_continue   --nostringval-- Dictionary stack:    --dict:1169/1684(ro)(G)--   --dict:0/20(G)--   --dict:123/200(L)--   --dict:100/300(L)-- Current allocation mode is local Current file position is 120580 MiKTeX GPL Ghostscript 9.05: Unrecoverable error, exit code 1   I use MiKTeX 2.9 and latest packages in Windows 7.


This example wanted to show if $k$ is a field, $X$ the affine line with a double point as in Ex 2.3.6, then X is not separated.  It argued that $X$(product over $k$)$X$ is affine plane with double axes and four origins. It is not closed because all four origins are in the closure of the diagonal.So the diagonal is not a closed immersion.  But I don't know how to display the product scheme explicitly. Although it looks natural, usually the underlying space of the product scheme may not be the product of the corresponding topological spaces.  I tried to construct it from the method in arbitrary product schemes but got messy. Can anyone help me with that?  Another question is if $ k$ is assumed to be algebraically closed here?

I know that the topological space of fibered product of schemes is generally distinct to the usual Cartesian product of toplogical spaces of schemes. Then how can we compute the top. sp. of fibered product of sch. explicitly? Is there any systematic procedure that I can do?  Actually this question arises from when I read the Hartshorne's Algebraic Geometry. In section 4 on Chapter2, the example says that the affine line with doubled origin(I may denote it by X) is not separated over the field k. In the explanation of the book, I can see that the top. sp. of the fibered product of two X . However, I cannot understand how to compute it. (If you want the exact statement, see the p.96 of Hartshorne)


I'm building a 5 V and 4 A circuit that will be in contact with the body.  How can I know if this amperage, in case something goes wrong, will not be a problem for my health or my life?

Related:        From what I've heard:   110 V (or 220 V; household voltage pretty much) is dangerous (i.e. can kill you) I think there's consensus on this, no need to try :) 60 V (old telephone lines) is supposedly dangerous (never tried, only heard it once... probably won't try)   From what I know first-hand:   9 V is not dangerous (I've put a 9-V battery on my tongue, nbd... actually it kinda hurt!) 1.5 V can indeed be quite shocking with enough current (fell for one of those "Do you want some gum?" tricks back in high school...), but they sometimes do not use 1.5 V with the low amperage levels, some use a DC motor to vibrate and complete the trick.   So I guess there's two parameters here, voltage and current... but are there rough numbers on how much of each (or in combination, which I guess would be power) would be considered hazardous?  No old telephone lines have always been 48vDC well at least since from 1950s, if your skin is wet you can feel it slightly, like on your forearm.  Now the ring voltage is 90-110vAC with a 2 on 4 sec off cycle (USA).  It will ring your bell but good, should you be touching the wires when someone calls. The ring voltage rides on top of the 48vDC, so its present on the same two conductors that the voice voltage(DC) is on. Luckily it's 4 seconds off will give you a chance to get off the conductors with a scream (of pain).


I am working on research involving probability tables. I simplified the problem to the following. Say we have the following:  $C_1, C_2, C_3, C_4$  $\forall i, C_i > 0$  $x = \frac{C_1 + C_2}{C_1 + C_2 + C_3 + C_4}$  $y = \frac{C_1}{C_1 + C_3}$  $z = \frac{C_2}{C_2 + C_4}$  I am almost positive (by just filling in numbers) that both $y$ and $z$ cannot $> x$ or $< x$. Meaning that unless $y = z$, then either $y < x$ and $z > x$ or $y > x$ and $z < x$. Does anyone have suggestions for an approach to prove this?   ==EDIT== Basically, I am trying to prove that either of these two situations are impossible:  $z \geq y > x$  $x > y \geq z$

We were trying to come up with an easy way to generate a rational number in between two existing rational numbers with a fairly low numerator and denominator (the way we were doing this earlier was to find the average of the two rationals, but that results in a denominator of up to $c * d$. Does this inequality hold for all values of $a, b, c, d$?


see also:   That question addresses why the TIF imported into QGIS has a dark gray background when the color set is set to 4096 when exported from PDFCreator.   That file's gdalinfo shows NBITS=4  Here, in this question, I would like to know if there is a way to render the dark gray transparent, much in the way that entering a "0" in  properties->transparency->no data value->additional no data value will make the black lines transparent.  Alternatively, is there a way to have QGIS render the dark gray as white?

using QGIS 2.6  I import a TIF file, and expect the import to show an image that has black lines on a white background (with some other colors here and there), as the native windows viewer will see a white background.   The file, 49MB, imports, but   The TIF image has a dark gray background instead of a white background  I can't tell why.   Any hints?  The same thing happens if I import the TIF image into georeference, which is how I discovered this in the first place.  I created/exported the TIF image using PDFCreator (from a print of a PDF to a TIF, using that program).   Within PDFCreator, I chose a TIF export that set the color map to 4096 colors, as the default created a TIF file that was twice as large.  On testing with the default size (16 million colors or some such).... That file imported and showed the background as white.  And I can't tell why, for that, either.   Any hints?  ======== In response to the comment/question by @BradHards:  The TIFFTAG_PHOTOMETRIC is not present in either file.  The gdalinfo for the large file and small file are identical, but for the presence of two extra lines on the file where the white background turns to dark gray.  Each band sets NBITS=4 for Image Structure Metadata: eg:     Band 1 Block=5100x68 Type=Byte, ColorInterp=Red   Image Structure Metadata:     NBITS=4 Band 2 Block=5100x68 Type=Byte, ColorInterp=Green   Image Structure Metadata:     NBITS=4 Band 3 Block=5100x68 Type=Byte, ColorInterp=Blue   Image Structure Metadata:     NBITS=4   Something about the NBITS=4 state turns the background dark gray.  Alternatively, there is some other problem with the PDFCreator export.  These are the full GDALInfo:  Small with dark gray background:   Driver: GTiff/GeoTIFF Files: small file.tif Size is 5100, 6600 Coordinate System is `' Metadata:   TIFFTAG_DATETIME=2015:01:28 16:41:04   TIFFTAG_RESOLUTIONUNIT=2 (pixels/inch)   TIFFTAG_SOFTWARE=GPL Ghostscript 9.07   TIFFTAG_XRESOLUTION=600   TIFFTAG_YRESOLUTION=600 Image Structure Metadata:   INTERLEAVE=PIXEL Corner Coordinates: Upper Left  (    0.0,    0.0) Lower Left  (    0.0, 6600.0) Upper Right ( 5100.0,    0.0) Lower Right ( 5100.0, 6600.0) Center      ( 2550.0, 3300.0) Band 1 Block=5100x68 Type=Byte, ColorInterp=Red   Image Structure Metadata:     NBITS=4 Band 2 Block=5100x68 Type=Byte, ColorInterp=Green   Image Structure Metadata:     NBITS=4 Band 3 Block=5100x68 Type=Byte, ColorInterp=Blue   Image Structure Metadata:     NBITS=4   Large with white background   Driver: GTiff/GeoTIFF Files: larger file.tif Size is 5100, 6600 Coordinate System is `' Metadata:   TIFFTAG_DATETIME=2015:01:28 17:07:16   TIFFTAG_RESOLUTIONUNIT=2 (pixels/inch)   TIFFTAG_SOFTWARE=GPL Ghostscript 9.07   TIFFTAG_XRESOLUTION=600   TIFFTAG_YRESOLUTION=600 Image Structure Metadata:   INTERLEAVE=PIXEL Corner Coordinates: Upper Left  (    0.0,    0.0) Lower Left  (    0.0, 6600.0) Upper Right ( 5100.0,    0.0) Lower Right ( 5100.0, 6600.0) Center      ( 2550.0, 3300.0) Band 1 Block=5100x68 Type=Byte, ColorInterp=Red Band 2 Block=5100x68 Type=Byte, ColorInterp=Green Band 3 Block=5100x68 Type=Byte, ColorInterp=Blue


I try to delete the folders in my update directory /Library/Updates, because my updates are corrupt and are failing. I need them to get downloaded again.  I tried it with the terminal like this sudo rm -Rf 041-57076 but it does fail with operation not permitted.  The output of ls -lO /Library/Updates/ is:  drwxr-xr-x 9 root wheel restricted 288 27 Mai 15:54 041-57076 ...   I only posted the relevant line

I'm running the command  sudo chmod 000 /System/Library/CoreServices/AirPlayUIAgent.app/Contents/MacOS/AirPlayUIAgent   Because AirPlay mirroring is messing with one of my programs, but it tells me "Operation is Not Permitted". I'm the owner of this Mac and should definitely be permitted, some help please?


Getting errors running sudo apt-get -f install:  "Reading package lists... Done Building dependency tree        Reading state information... Done Correcting dependencies... Done The following packages were automatically installed and are no longer required:   gstreamer1.0-plugins-base:i386 libcdparanoia0:i386 libdbusmenu-qt2:i386 libgstreamer-plugins-base1.0-0:i386 libgstreamer1.0-0:i386 libopus0:i386 liborc-0.4-0:i386 libqt4-opengl:i386   libqtwebkit4:i386 libtheora0:i386 libvisual-0.4-0:i386 libvlccore8 libxss1:i386 libxv1:i386 linux-headers-4.4.0-101 linux-headers-4.4.0-101-generic linux-headers-4.4.0-96   linux-headers-4.4.0-96-generic linux-headers-4.4.0-97 linux-headers-4.4.0-97-generic linux-headers-4.4.0-98 linux-headers-4.4.0-98-generic linux-image-4.4.0-101-generic linux-image-4.4.0-96-generic   linux-image-4.4.0-97-generic linux-image-4.4.0-98-generic linux-image-extra-4.4.0-101-generic linux-image-extra-4.4.0-96-generic linux-image-extra-4.4.0-97-generic linux-image-extra-4.4.0-98-generic   sni-qt:i386 vlc-plugin-notify vlc-plugin-samba vlc-plugin-video-splitter vlc-plugin-visualization Use 'sudo apt autoremove' to remove them. The following additional packages will be installed:   libvlccore9 The following NEW packages will be installed:   libvlccore9 0 upgraded, 1 newly installed, 0 to remove and 25 not upgraded. 14 not fully installed or removed. Need to get 0 B/472 kB of archives. After this operation, 1,240 kB of additional disk space will be used. Do you want to continue? [Y/n] y     (Reading database ... 462617 files and directories currently installed.) Preparing to unpack .../libvlccore9_4.0.0~rc1~~git20171225+r73378+113~ubuntu16.04.1_amd64.deb ... Unpacking libvlccore9:amd64 (4.0.0~rc1~~git20171225+r73378+113~ubuntu16.04.1) ... dpkg: error processing archive /var/cache/apt/archives/libvlccore9_4.0.0~rc1~~git20171225+r73378+113~ubuntu16.04.1_amd64.deb (--unpack):  trying to overwrite '/usr/lib/x86_64-linux-gnu/libvlccore.so.9.0.0', which is also in package libvlccore8:amd64 3.0.0~~git20171210+r73147+99~ubuntu16.04.1 dpkg-deb: error: subprocess paste was killed by signal (Broken pipe) Processing triggers for libc-bin (2.23-0ubuntu9) ... Errors were encountered while processing:  /var/cache/apt/archives/libvlccore9_4.0.0~rc1~~git20171225+r73378+113~ubuntu16.04.1_amd64.deb E: Sub-process /usr/bin/dpkg returned an error code (1)"   Tried several options and could not fix it. Any help appreciated!  Thx

For example:  $ sudo apt-get install curl Reading package lists... Done Building dependency tree Reading state information... Done You might want to run 'apt-get -f install' to correct these: The following packages have unmet dependencies: bsh : Depends: libjline-java but it is not going to be installed groovy : Depends: libjline-java but it is not going to be installed rhino : Depends: libjline-java but it is not going to be installed E: Unmet dependencies.   Try 'apt-get -f install' with no packages (or specify a solution).   I get the same or similar errors when I attempt to install clojure1.3, leiningen, and several other packages.   When I try the suggestion made in the error message, this is what happens:  $ sudo apt-get -f install  Reading package lists... Done Building dependency tree        Reading state information... Done Correcting dependencies... Done The following packages were automatically installed and are no longer required:   diffstat linux-headers-3.2.0-26-generic linux-headers-3.2.0-26 dh-apparmor dkms html2text libmail-sendmail-perl libsys-hostname-long-perl Use 'apt-get autoremove' to remove them. The following extra packages will be installed:   libjline-java Suggested packages:   libjline-java-doc The following NEW packages will be installed:   libjline-java 0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded. 23 not fully installed or removed. Need to get 0 B/72.0 kB of archives. After this operation, 129 kB of additional disk space will be used. Do you want to continue [Y/n]? Y (Reading database ... 226243 files and directories currently installed.) Unpacking libjline-java (from .../libjline-java_1.0-1_all.deb) ... dpkg: error processing /var/cache/apt/archives/libjline-java_1.0-1_all.deb (--unpack):  trying to overwrite '/usr/share/java/jline.jar', which is also in package scala 2.9.2-400 Errors were encountered while processing:  /var/cache/apt/archives/libjline-java_1.0-1_all.deb E: Sub-process /usr/bin/dpkg returned an error code (1)  $ sudo apt-get upgrade Reading package lists... Done Building dependency tree        Reading state information... Done You might want to run 'apt-get -f install' to correct these. The following packages have unmet dependencies:  bsh : Depends: libjline-java but it is not installed  groovy : Depends: libjline-java but it is not installed  rhino : Depends: libjline-java but it is not installed E: Unmet dependencies. Try using -f.


Prove that there are an infinite number of primes of the form $4n - 1$. I am having trouble solving this problem, so any help would be appreciated.

This is the proof from the book:     Theorem. There are infinitely many primes of the form $4n+3$.    Lemma. If $a$ and $b$ are integers, both of the form $4n + 1$, then the product $ab$ is also in this form.  Proof of Theorem: Let assume that there are only a finite number of primes of the form $4n + 3$, say  $$p_0, p_1, p_2, \ldots, p_r.$$ Let $$Q = 4p_1p_2p_3\cdots p_r + 3.$$ Then there is at least one prime in the factorization of $Q$ of the form $4n + 3$. Otherwise, all of these primes would be of the form $4n + 1$, and by the Lemma above, this would imply that $Q$ would also be of this form, which is a contradiction. However, none of the prime $p_0, p_1,\ldots, p_n$ divides $Q$. The prime $3$ does not divide $Q$, for if $3|Q$  then $$3|(Q-3) = 4p_1p_2p_3\cdots p_r,$$ which is a contradiction. Likewise, none of the primes $p_j$ can divides $Q$, because $p_j | Q$ implies $p_j | ( Q - 4p_1p_2\cdots p_r ) = 3$, which is absurd. Hence, there are infinitely many primes of the form $4n +3$.   END  From "however, none of the prime ...." to the end, I totally lost!    My questions:   Is the author assuming $Q$ is prime or is not? Why none of the primes $p_0, p_1,\ldots, p_r$ divide $Q$? Based on what argument?     Can anyone share me a better proof?     Thanks.


This question here asks about answering negative questions:      I have a completely different question. I want to know:   how do we agree or disagree with negative statements in English.   Example:  ––This is not a duplicate question.  ––Yes, it is a new one.  or  ––This is not a duplicate question.  ––No, it is a new one.

Q: "Don't you know?"   If I really don't know, how should I respond to this question? Yes or No?  There's a similar question on EL&U, but the answer isn't clear how it works:      Also here on ELU too:      These answers are confusing. I want to know what one word answer I can use. In other words I want to know:   What will native speakers understand if I reply No to this question? What will native speakers understand if I reply Yes to this question?


This question has been answered a couple of times on this site for other versions of Ubuntu, but the proposed solutions no longer work in Ubuntu 13.04. Specifically, I tried the solution described . However, after following the instructions on that link (i.e. creating a Skype AppArmor profile), skype fails to load with the following error message:   /usr/bin/skype: 8: exec: /usr/lib/skype/skype: Permission denied.   Strangely, the same permission denied error happens if I try sudo skype. So is there another way to remove the skype panel indicator in Ubuntu 13.04, preferably without removing sni-qt?

As I use the Docky Skype indicator, and the green Skype icon doesn't look good next to all the grey ones -- it would be nice to remove the icon from the system tray.   Is this possible? How can I do it in Ubuntu 12.04 -- or other earlier versions?