Edit: This Question was marked duplicate of  but its not duplicate one, here i am asking about does this problem happening because of icu4j jar and WebSphere.    I am running application on WebSphere 7 and i am using STS for development at one point i am calling UCharacter.offsetByCodePoints from icu4j 58.2 jar that i have added my application's web-inf/lib folder. when i click on method STS is able find this method but at run time i am getting below error.        java.lang.NoSuchMethodError: com/ibm/icu/lang/UCharacter.offsetByCodePoints(Ljava/lang/CharSequence;II)I   I have added this jar at every required place like in WEB-INF/lib folder.  Is it due to WebSphere is getting confused between sun.text.normalizer.UCharcter and com.ibm.icu.lang.UCharacter or does webSphere has older version of icu4j or what ?  What could be possible solution for it.

I'm getting a NoSuchMethodError error when running my Java program.  What's wrong and how do I fix it?


In general, there's a lot of push back against documenting why a post gets deleted. In looking at various posts similar to this, it's been explained that nothing really needs to be documented, that the reasons for deleting a post are pretty clear.   That any requirement to document a reason could be circumvented.  That there are not enough admins and more than enough users...etc...  In my humble opinion, it should be done, in fact it should be 100 percent mandatory.  I can give a great example why:  I'm well aware that there are a few reasons an answer can be deleted. The most glaring is if  you don't answer the question. The other reasons are: Answers that do not fundamentally answer the question may be removed. This includes answers that are:  commentary on the question or other answers  asking another, different question  “thanks!” or “me too!” responses  exact duplicates of other answers  barely more than a link to an external site  not even a partial answer to the actual question   Now, on the answer I linked to, the answer given doesn't qualify as any of the above reasons. It is, in fact, a different explanation for the error with an explanation that included an image.   However, a mod came by and deleted that answer and in fact, turned it into . If you'll look at the comment, it's ended before the actual answer is ended and the image is removed, both of which change the answer. Without a comment as to why this was deleted there's no way to tell what the mod thought was wrong with the answer. To add to this, it can't be undeleted if you have less than 50 points.  You can flag it, HOWEVER if you do that, you must explain why you're flagging it. In other words, you have to make a case for un-deletion but the mod / admin that deleted has to do nothing other than click a button.  That's simply not correct. In both cases documentation needs to exist. This does two things:  It allows the user to see why the admin/mod deleted it, and it creates a record for other admins / mods to view and to see why this was deleted.  It allows the user to see what rule was violated and why. That way the user learns. It also gives the user something to challenge directly , if they choose to do so. As of right now, the challenge is blind and as a result, unfairly weighed in the direction of the mod.  Allows for documentation on the admins side, in case this user is engaging in a pattern of disruptive behaviour. For example, if this user's contributions were looked at and say they had 10 good posts and 3 deletions all in one area for the same reason, this could be used to show a pattern of behaviour in one area, creating a real and convincing reason for this user to be possibly banned or blocked from a certain area in stack.   As you can see, this is a case where everyone wins. There's literally no reason not to do it. As to the reasons against: The reasons are clear - although we have a link that explains why posts can be deleted, I think you'll agree this post doesn't fit any of those rationales, therefore a note from the admin would have been extremely helpful (see points 1 , 2 and 3 ).  The pointers on the question offer on generic explanations and not specific explanations as to the reason for deletion. That it can circumvented - Yes, nothing's 100 percent foolproof, but if any admin/mod tries to circumvent this, they should loose their mod/admin rights on the spot. Too many users, not enough admins - That's true of any site. HOWEVER you have to remember, although we can flag that post and ask for it to be reviewed, we're absolutely required to give reasons for our flag, we can't just flag it and be done with it.  Further, we can't undelete our message and request a concensus from other users. It's obvious that the system is weighed in favor of the admins / mods - so I propose to even the odds, if the admins / mods want to delete a message, they must indicate why this is so.  Once again, per points 1 , 2 and 3 it's an everyone wins situation.

Could we have a method of explaining why we think a question or answer should be deleted?  It could work identically to closing a question, maybe with an additional text-input box (like the "Requires Moderator attention" flag option) to provide additional info because the reasons for deletion should really be more specific..  For example, "exact duplicate" doesn't explain to me the user has re-posted the same question, thus, it should definitely be deleted (not just left closed). Like with close-messages, these reasons would be listed under the deleted item (or answer).   I don't think comments are suitable, as they can be a pain to quickly.. "extract" deletion reasons from them - I have to scan through the comments, and they may all be irrelevant.  Equally, for un-deletion, it'd be useful to know why another user thinks a question should be restored. For example "new user deleted the question after they accepted an answer", or "Jeff went insane and started deleting any questions with the letter O in it".  I think requiring un-deletion reasons is possibly more important, since commenting is disabled on deleted questions - we have no way of explaining why we think it should be restored


Why this limit does not exist?  $$\lim_{z\to 0}\frac{(\bar{z})^2}{z^2}$$  I know that the limit exists and equals to $1$ is $z$ is real. When $z$ is complex, I tried  $$\frac{(\bar{z})^2}{z^2}=\frac{e^{-2i\theta}}{e^{2i\theta}}=e^{-4i\theta}$$  Then put the limit back,  $$\lim_{z\to 0} \frac{(\bar{z})^2}{z^2}=\lim_{z\to0} e^{-4i\theta}$$  Then I got a little bit confused because I wasn't sure if $\lim_{z\to 0}$ is equivalent to $\lim_{r\to 0}$? I was thinking something like "$z$ gets small iif $\|z\|$ gets small iif $r$ gets small".

For$$\lim_{z\rightarrow0}\frac{\bar{z}^2}{z^2}$$   Does $\lim_{z\rightarrow0}\frac{\bar{z}^2}{z^2}$ exist? If the answer is no, why? Does $\bar{z}$ represents $a-bi$?


I have a folder with a complicated folder structure:  ├── folder1 │   ├── 0001.jpg │   └── 0002.jpg ├── folder2 │   ├── 0001.jpg │   └── 0002.jpg ├── folder3 │    └── folder4 │         ├── 0001.jpg │         └── 0002.jpg └── folder5      └── folder6            └── folder7                 ├── 0001.jpg                 └── 0002.jpg      I would like to flatten the the folder structure such that all the files reside in the parent directory with unique names such as folder1_0001.jpg, folder1_0002.jpg etc.  I have attempted to use the code suggested in    $ find */ -type f -exec bash -c 'file=${1#./}; echo mv "$file" "${file//\//_}"' _ '{}' \;   The echo demonstrates that it is working:  mv folder3/folder4/000098.jpg folder3_folder4_000098.jpg   But the output files are not placed in the parent directory and I have searched the drive cannot be found the output files.  I have also attempted    $ find . -type f -name "*.jpg" | sed 'h;y/\//_/;H;g;s/\n/ /g;s/^/cp -v /' | sh   -v demonstrates that it is working:  ‘./folder3/folder4/000098.jpg’ -> ‘._folder3_folder4_000098.jpg’   However the output creates hidden files in the parent directory, this complicates my workflow. I am able to view these hidden files in the parent directory using ls -a   I have also tried the suggested code below from    find . -mindepth 2 -type f | xargs mv --backup=numbered -t . && find . -type d -empty -delete   But the command overwrites files with similar file names.   Any suggestions on how to flatten the folder structure without overwriting files with similar names?    My ultimate goal is to convert the unique names into sequential numbers as described in    a=1   for i in *.jpg; do   new=$(printf "%04d.jpg" "$a") #04 pad to length of 4   mv -- "$i" "$new"   let a=a+1  done

I have this folder structure:  ├── foo1 │   ├── bar1.txt │   └── bar2.txt ├── foo2 │   ├── bar3.txt │   └── bar4 with a space.txt └── foo3     └── qux1         ├── bar5.txt         └── bar6.txt   that I would like to flatten into this, with an underscore between each folder level:  ├── foo1_bar1.txt ├── foo1_bar2.txt ├── foo2_bar3.txt ├── foo2_bar4 with a space.txt ├── foo3_qux1.bar6.txt └── foo3_qux1_bar5.txt   I've looked around and I haven't found any solution that work, mostly I think because my problem has two particularities: there might be more than one folder level inside the root one and also because some files might have spaces.  Any idea how to accomplish this in bash? Thanks!  Edit: Running gleen jackman proposed answer I get this:    There are two underscores for the first level folder. Any idea how to either avoid this or just rename it so that is just one underscore? Thanks.


Writing code to reverse the elements in an array. Both method1 and method2 perform the same operations, but are changing the values of the array in main, despite scope and no assignment.  import java.util.Arrays; public class ReversingMatrix {     public static void main(String[] args) {         int values[] = {1, 2, 3, 4, 5, 6, 7};         method1(values, 0, values.length - 1);             // Values array is now : {7, 6 ... 1} --> why?         method2(values);     }     public static void method1(int[] arr, int lPos, int rPos) {         if(lPos >= rPos) System.out.println("1D Recursion Reverse: " + Arrays.toString(arr));         else {             int temp = arr[lPos];             arr[lPos] = arr[rPos];             arr[rPos] = temp;             method1(arr, lPos + 1, rPos - 1);         }     }     public static void method2(int[] arr) {         int temp;         for(int a = 0; a < arr.length / 2; a++) {             temp = arr[a];             arr[a] = arr[arr.length - (1+a)];             arr[arr.length - (1+a)] = temp;         }         System.out.println("1D For Loop Reverse: " + Arrays.toString(arr));     } }   Why doesn't values array remain {1, 2, 3, 4, 5, 6, 7}, so I can use it multiple times?

I always thought Java uses pass-by-reference. However, I've seen a couple of blog posts (for example, ) that claim that it isn't (the blog post says that Java uses pass-by-value). I don't think I understand the distinction they're making. What is the explanation?


The counselor recommended that he go to a community college.   I found the above example . What is the context and why not goes after he?

I am confused between the two.     I demand that he leave!or I demand that he leaves!      I demand that this man leave!or I demand that this man leaves!   Which is correct with s or without and why?


Gilles :     character 27 = 033 = 0x1b = ^[ = \e   Demizey :     ^[ is just a representation of ESCAPE and \e is interpreted as an actual ESCAPE character   Then I also found this line from a      Make sure you write the key sequence as \e[24~ rather than ^[[24~. This is because the ^[ sequence is equivalent to the [Esc] key, which is represented by \e in the shell. So, for instance, if the key sequence was ^[[OP the resulting bind code to use would be \e[OP.   But I have been using mappings that use ^[ instead of \e.  So are they interchangeable? When do I need use one instead of the other?


Let $H$ and $K$ be subgroups of a group $G$. Then is the following true ?      If $[G : H] < ∞$ and $[G : K] < ∞$, then $[G : H ∩ K] < ∞$.   I think this's false because there's still a case that $H ∩ K$ could be empty. But the textbook requires to prove this statement. So I am a bit confusing on this point.. any help?

Let $(G,*)$ be a group and $H,K$ be two subgroups of $G$ of finite index (the number of left cosets of $H$ and $K$ in $G$). Is the set $H\cap K$ also a subgroup of finite index? I feel like need that $[G\colon(H\cap K)]$ is a divisor of $[G\colon H]\cdot[G\colon K]$, but I dont't know when this holds.  Can somebody help me out?


We decided to travel to Croatia using ferry, train and coach from the UK. We had booked our train tickets through DB and actually had three trains on that ticket. We successfully caught our first train from Bruges to Brussels. We were then due to  catch a train to Frankfurt and then a further connection onwards to Munich. We then had an overnight train to Zagreb.  Our train from Brussels to Frankfurt was cancelled and the solution from Belgian Railways was to catch a train towards the Belgian/German border from where buses would take us to Aachen. This is because it was a German service. From there we had to catch a train to Cologne and then a train to Munich. Obviously we missed our connection from Frankfurt and then from Munich as we didn't arrive in Munich until 1.45am (we were due at 21.20). We had to pay for coach tickets from Munich to Zagreb so we didn't lose a day of our holiday.  Which parts of that should DB compensate us for?  EDIT:  Thought I should add a little more detail. Our train from Bruges-Brussels, Brussels-Frankfurt and then Frankfurt-Munich were booked through DB. Our train from Munich to Zagreb was booked through Austrian Railways.  On being told by Belgian Railways that the train was cancelled I told them that we had an onward connection from Munich that evening. The guy spoke to his supervisor and he said that we'd need to get into Germany and speak to someone. Once we reached Verviers there was a bus to Aachen station. From there we were on our own. There were 2 people trying to assist the hundreds who had arrived on buses. We sort of pushed in and tried to explain that we needed to get to Munich for our onward connection. We were given a printout of train times to Munich and that was it.   When we got to Cologne I went to the Travel Centre and explained the situation and the staff member stamped my ticket and gave me a complaints form. She then suggested a direct train to Munich which was due to arrive at about 1.30am. She said that when we arrived in Munich we should go to the Travel Centre and they would give us a hotel voucher.   En route we had to decide what our options were. If we arrived at 1.30am and then had to find a hotel it would mean that we'd probably be in the hotel for no more than 4 hours before we had to return to the station for the 8.20 train to Zagreb. On arrival in Zagreb we had a 7 hour coach journey to our destination. This would have meant that getting the train to Zagreb the following morning would mean we would arrive in Zagreb at 17.00 and even if we were able to get on a coach straight within the hour we wouldn't arrive at our destination until 3.00 or 4.00am the following morning and we had no idea if we'd be able to get into our accommodation at that time. So we looked at other options and found a coach that left at 3.15am from Munich arriving in Zagreb at 11am, only 2.5 hours after our original arrival time. We thought this was a better option. There was nobody on the train who we could clarify this with, the only staff onboard didn't even bother looking at our tickets. So we went ahead and booked the coach.  By the time we arrived in Munich it was 1.45 and the Travel Centre was just closing for the night. I went and explained our situation but there was no offer of a hotel or an offer to pay for a hotel, just another stamped form. So we continued with our coach booking just so we could keep on moving and get to our holiday quicker.   Hope this clarifies a few details!

I recently traveled from the Basel area to Stuttgart for a weekend.  I had round-trip tickets including (paid) bicycle reservations.  At our first station change, we found that our EC train was canceled.  Information gave us a replacement train schedule, using slow RE trains which don't require reservations for bicycles.  As we continued our trip, every single train we boarded arrived late, eventually causing us to reach Stuttgart roughly 2 hours later than our initial itinerary.  What monetary compensation am I justified in requesting from Deutsche Bahn in this case?  In particular:   It seems clear I should get back the bicycle reservation money, since the train we reserved on was canceled. I know DB offers compensation for late travels.  I'm not sure whether we were 2 hours late or more, or just shy of 2 hours.  But does this apply if we weren't traveling by our original trains? If we had originally scheduled our journey with RE trains and other local transport, we could have bought a Baden-Württemberg ticket for much cheaper than our tickets including an EC cost.  Can I ask them to refund the difference? Am I entitled to any other type of compensation?


I'm asked to design a large banner 10m * 4m. I'm not sure how should I start with Photoshop. Should I create one with small size and high resolution? What is the number of PPI suitable for this size?  OR should I work with the actual size? If yes , Will Photoshop crash ? What is the number of PPI at actual size?  Thanks in advance :)

(This question is meant to be a resource to direct others to given that this is a common question.)  Given the task of creating an image that will be printed at a certain size, what pixel dimensions and resolution should I be setting my file at?


Q. The gravitational field due to a mass distribution is given by $E=k/(x^3)$ in $x$-direction. Taking the gravitational potential to be zero at infinity, find its value at a distance $x$. for the answer let the 'integral where the lower limit is infinity and upper limit x' be denoted as I The answer my textbook gives to the above question is :  shouldn't the dot product of E and dx (because we are traveling from infinity to a point) give - sign so the final answer should be negative.

A solid sphere has charge $q$ and radius $R$. Find the potential at a point a distance $r$ from the center of the sphere where $r>R$, using infinity as the reference point.  My attempt:  From Gauss' theorem we may deduce that $\displaystyle\mathbf{E}=\frac{1}{4\pi\epsilon_0}\frac{q}{r'^2}\hat{\mathbf{r}}$ where $r'$ is the distance of an arbitrary point from the center of the sphere provided $r'>R$.  $V=-\int_\infty^\mathbf{r}\mathbf{E}\cdot d\mathbf{l}$  My question: What is $d\mathbf{l}$? Since we are traversing in the direction opposite to $\hat{\mathbf{r}}$, I think it should be $-dr'\hat{\mathbf{r}}$. But when I use it to find $V$, I get a sign error. Please help!


hello guys I did not understand why we put * here   def print_people( # here # *people # here #): for person in people:     print("hello" + person)   print_people("blabla" , "love" , "blabla")

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


I am trying to update current items, but all items in the list get updated why?   public override void ItemAdding(SPItemEventProperties properties)     {         using (SPWeb web = properties.OpenWeb())         {              SPList myList = web.Lists.TryGetList("DocumentList");             SPListItemCollection itemCollection = myList.Items;             web.AllowUnsafeUpdates = true;              for (int iCount = 0; iCount < itemCollection.Count; iCount++)             {                  SPListItem _item = itemCollection[iCount];                  _item["MyField"] = "";                 _item.Update();             }             }}

I am trying to update list field using ItemAdding,  public override void ItemAdding(SPItemEventProperties properties)     {           SPListItem curListItem = properties.ListItem;         curListItem.Web.AllowUnsafeUpdates = true; // This property should be set to true for the update to go through         curListItem["Age"] = "";         curListItem.Update(); // This line should update the ListItem but it doesnt      }   UPDATE    public override void ItemAdding(SPItemEventProperties properties)     {          string empty = "";         properties.AfterProperties["Age"] = empty;         base.ItemAdding(properties);      }


I'm looking for the symbol above but I can't find them anywhere. Could someone help me identify it?

I know what my symbol or character looks like, but I don't know what the command is or which math alphabet it came from. How do I go about finding this out?


When I draw to a TCanvas using LineTo(), the lines end with a half circle bulge on them, not by a cut.  How can I disable this ending using the Windows API or Delphi's graphic system?

Is there any way to set the style for the lineends for the TCanvas.LineTo method? It seems to default to rounded ends, which looks very bad for several lines in a row of different colours when Pen.Width is set to a large value (e.g. 9).  It looks like this (rounded ends):   ********........****** **********........****** **********........******  ********........******   (where * is e.g. blue and . is yellow)  It is even worse if the two outer lines are drawn after the middle line:   ********........****** **********......******** **********......********  ********........******   I'd like it to look like this (streight ends):   ********........******  ********........******  ********........******  ********........******   Pen does not seem to offer any setting for this and neither does the LineTo method. Is there maybe a windows API function I could call?


I've modified a file in AppData/LocalLow to be 'read only'. Then I'm trying to undo the 'read-only' and I'm getting that I need the permissions of myself - meaning the permission of my user that now I am being logged in with this user. Also I can't delete the file. Any help?

I updated my laptop's OS from Windows XP to Windows 7. There are some leftover files from Windows XP on the computer now. If I try deleting them I get the following error:     You need permission to perform this action.      You require permission from S-1-.... to make changes to this folder.   What's weird is that I am logged in with the only user account on this machine and I have administrator privileges. I tried turning UAC off, but I still can't delete the files.  How can I force removal of these files?


I compiled PHP and compilation went fine (no errors). On the make test step I get one test that doesn’t pass. Should I ignore it since the compilation went right anyway or should I do something about it?  Relevant test output is:   ===================================================================== FAILED TEST SUMMARY --------------------------------------------------------------------- bool checkdnsrr ( string $host [, string $type = "MX" ] ); [ext/standard/tests/checkdnsrr.phpt] =====================================================================   The following communities don’t seem to fit:   Stack Overflow is for programming questions Server Fault is for sys-admin stuff, I guess Unix & Linux is for sys-admin stuff for Unix-like OSes Super User is for help with apps or userland OS questions.   Any suggestions?

There seems to be more than a few computer science/programming Stack Exchange networks (is that the correct term?). Stack Overflow, being the first, has by far the most users, questions, and answers.  What is the reasoning for creating the others, and are there clear guidelines for which kinds of questions should be posted? I can see a large amount of potential overflow, many cases of people not getting a good answer to their question, because the person who has the answer isn't browsing that particular network at the moment.  I understand that they were probably created for organizational purposes, but wouldn't it almost make more sense to just have them as categories under Stack Overflow, keep them separated but still connected, instead of making people have to create multiple 'account's, one for each network?  I am sure there was a very good reason to break them up, but as someone that is new to SE, it can be somewhat intimidating to decide which one to post in to ensure you get a good answer. For example, if I am a computer science student, my first instinct might to be to post in the computer science network, until I see that it literally has 1% of the users as the Stack Overflow network, which still seems to be for programming/computer science related questions.  So my second instinct would then to be to post it into the Stack Overflow site on the basis that I have a significantly higher chance of my question being seen and getting a good answer. Then I notice that there is also a 'programmers' network, and I don't even begin to know where that fits in. I, and I am assuming most people, will probably just post on Stack Overflow to be safe.  My question is, other than the short little description blurb of each one, is there a clear cut set of guidelines which what each network is intended for, what kinds of questions should go to each one, and is anything being done to encourage people to post in these newer, smaller (more specialized?) networks as opposed to just posting in big daddy Stack Overflow?  Now again, this is for computer science/programming/"why isn't this code doing what I want?" related questions, I am not saying that if I had a question about Linux or WordPress or something I would have the same confusion.


I'm new to Ubuntu and am running an old unsupported release and would like to gain some understanding of how the release schedule works.   What the difference is between an  end of life and a supported release is and how I can go about moving to a supported release?   Here's the extent of what I know: Windows executables don't run natively on Ubuntu and my update manager says the Ubuntu I have is no longer supported.

Recently I have installed an older version of Ubuntu on my old machine. Whenever I try to install any software, I get an error saying it couldn't be found:  $ sudo apt-get install vlc Reading package lists... Done                Building dependency tree        Reading state information... Done     E: Couldn't find package vlc


I am  modeling wood properties variation of several individual within the same tree species using multilevel lme().  I specified a first model as :   full <- lme(id ~ dist2 + I(dist2^2)                  ,data=dataGr                  ,random=list(ind=pdDiag(~ dist2 + I(dist2^2)),                               radius=pdDiag(~ dist2 + I(dist2^2)))                  ,control=ctrl, meth='ML')   with 'radius' nested within 'ind'.   As 'id' is a longitudinal variable  according to 'dist2' within 'radius' within 'ind', I want to add an AR(1) autocorrelation error term.  So, I wrote a second model by updating the first one with  :   fullc <-   update(full,  correlation=corARMA(p=1,q=0, form = ~ 1 | ind/radius))   Is it a good way to include autocorrelation error structure in my model?  This specification is also possible and gives slightly different results :    fullc <-   update(full,  correlation=corARMA(p=1,q=0, form = ~ dist2 | ind/radius))   But I don't clearly understand the difference between both specifications. Could you help me ?   Thank you.  Romain.

There's a lot of discussion going on on this forum about the proper way to specify various hierarchical models using lmer.  I thought it would be great to have all the information in one place. A couple of questions to start:   How to specify multiple levels, where one group is nested within the other: is it (1|group1:group2) or (1+group1|group2)? What's the difference between (~1 + ....) and (1 | ...) and (0 | ...) etc.? How to specify group-level interactions?


I was wondering about Dumbledore's age. What justifies that he's so old, as described in the books and websites. My first guess was that he owns one of the Hallows, but then, how could Abelforth be that old ans alive too? Then I came across this question  and notably the first answer, stating that JK Rowling says that "Wizards have a much longer life expectancy than Muggles. (Harry hasn't found out about that yet.)". This would render Dumbledore longevity not that impressive at all... Do we have any more information about Wizards life-span? And how come that every pure blood kid seems unaware of that too?

In the Harry Potter series is it clear that magically-inclined individuals (witches/wizards) will live to be considerably older than their Muggle counterparts? From the question , it is given that Dumbledore was roughly 115 years old when he died, and at that age he hardly seemed ready to kick the bucket naturally.  With that in mind, how old will a wizard typically live to be, barring accidents or murder?


I want to use VirtualBox but it is giving me the error VT-x/AMD-V hardware acceleration is not available on your system. And in the virtual box settings, I am not able to open accelerator tab as it's frozen:    Please give me a step-by=step guide on how to fix this.

So I am trying to run Ubuntu in a virtualbox but on installing 12.10 from the .iso I was greeted by a warning telling me that audio wouldn't work then I pressed next and this popped up:  Failed to open a session for the virtual machine Tux 3 VT-x features locked or unavailable in MSR (VERR_VMX_MSR_LOCKED_OR_DISABLED) Details  Result Code:  E_FAIL (0x80004005) Component:  Console Interface:  IConsole {db7ab4ca-2a3f-4183-9243-c1208da92392}   And then it doesn't work.  I assigned 4GB of my 8GB to Ubuntu, 100 dynamically allocated GB of space, and 12MB of graphics memory. I'm running an Asus p8z77 V LX mobo with an Intel i5 3550 processor.   Downloaded 12.04.2 on my PC and tried again. Still getting the same message.


$ lsb_release -a   No LSB modules are available.   Distributor ID:   Ubuntu   Description:  Ubuntu 16.04.3 LTS   Release:  16.04   Codename: xenial $ sudo apt-get install rpcbind   Reading package lists... Done   Building dependency tree          Reading state information... Done   Package rpcbind is not available, but is referred to by another package.   This may mean that the package is missing, has been obsoleted, or is only available from another source    E: Package 'rpcbind' has no installation candidate $ sudo apt search rpcbind   [sudo] password for mohet01:    Sorting... Done   Full Text Search... Done     How to install rpcbind?

There are now errors when updating and I cannot install most software due to a corrupted  /etc/apt/sources.list   file. Is there a copy I can download to replace it?  The file would be for Ubuntu 12.04 (Final Beta) in the United States.


list[0:9] and list[1:10] were showing same in my python IDLE. I'm not sure the logic behind, could some one please explain. Please see the values retrieved below.  >>> list[0:9] [1, 2, 3, 4, 5, 6, 7, 8, 9] >>> list[0:10] [1, 2, 3, 4, 5, 6, 7, 8, 9]

I need a good explanation (references are a plus) on Python's slice notation.   To me, this notation needs a bit of picking up.   It looks extremely powerful, but I haven't quite got my head around it.


I have a set of neutral density filters that are rated as .3, .6, and .9 stops. Are they actually multiples of 0.3, or are they really multiples of 1/3? For example 1/3, 2/3, and 1 stop? If I stack the .3, .6, and the .9 is that 1.8 stops or 2 stops?  If it really is multiples of .3, what's the reasoning for that?

When I search on Amazon for eg. neutral density 67mm, I get long list of different filters. Some of them are marked like: ND2, ND4, ND8 etc. I'm guessing this means 2-, 4- or 8-stops filter, am I right?  But what about filters, that say 0.6 or 0.9? What does this mean?   Is there any other thing (apart of stops and diameter) that I should also pay attention to when choosing a filter?


I'm learning about iterative methods to solve the system $Au = f$, and I came across the following in my book:     To construct an iterative scheme, we assume that a non-singular matrix $M$ exists and define the matrix $N$ as $N = M - A$. We can then write $$A = M - N$$ The linear system $Au = f$ can then be written as $Mu = Nu + f$. By multiplying to the left and right with $M^{-1}$ we can define an iterative scheme $$\begin{split}u^{k+1} &= M^{-1}Nu^k + M^{-1}f\\&=M^{-1}(M-A)u^k + M^{-1}f\\&=u^k + M^{-1}(f - Au^k)\\&=u^k + M^{-1}r^k\end{split}$$   Question: This all makes a lot of sense to me, except for one thing; why is it allowed to write $u^{k+1} = M^{-1}Nu^k + M^{-1}f$ with the superscripts $k+1$ and $k$ over $u$? The construction of an iterative method goes from $Mu = Nu + f$ to $u^{k+1} = M^{-1}Nu^k + M^{-1}f$ and I don't understand how.  Thanks in advance!

Firstly let me preface by saying I wasn't sure if this is the correct site to ask the question.  I am currently trying to gain a better understanding of where iterative methods to solve systems such as $Ax=b$ come from and I am missing what I think is quite a fundamental understanding.  The question is fairly simple.  Often we want to solve the aforementioned system but it isn't practical for reasons of stability etc to compute an inverse of $A$ and directly solve $x=A^{-1}b$.  So instead we aim to solve it using an iterative method by splitting $A$ into parts.  For example if we perform the following splitting of $A$, $A=S-T$, we could write   $$ Ax = b\\ Sx_{n+1}=Tx_n+b. $$  What I want to know is why does this now become an iterative system, other than the fact I have written it as such.  For me personally I would not come up with the step to split $A$ into $S$ and $T$ and then re-write iteratively.  I might split it and end up with a line such as   $$Sx=Tx+b$$  but I wouldn't make the jump myself to make it $iterative$.  I know how to apply the methods and I get that by doing so we slowly improve our guess for $x$ each time until we converge to a solution.  But why?  I am just making it iterative because I have been taught that's what to do.  I hope I managed to express what I don't get clearly but if I haven't please let me know.


This question has been asked before, but I have a different problem and the posted one is way outdated.  The problem is that I need an old and new firefox running at the same time to run a plugin called "Digital Pali Reader"  which will not work with the newer firefox. I followed the instructions from the website  and downloaded from:   It worked like a charm until I ran the new firefox.  Then it disabled the plugins which was the goal of running the old version.

What is the most straight forward way to downgrade Firefox 57 to Firefox 56?   This is to have more time to wait for working replacements for legacy extensions.


Take a look at attached picture of one of my wall outlet. I am removing switch from this outlet to make it always hot, and use that switch to control recessed lights. As you can see, 2 of the neutral push in connectors already occupied by 2 neutral wires ( one from power source and other going to next outlet). I need to connect 3rd neutral wire from switch( recessed lights). Can I use side screw to connect 3rd neutral wire ?

I'm tying into an existing outlet box to provide power for a new electrical outlet. The existing outlet already has 2 lines connected to it - one from "upstream" (to the fuse box) and one downstream to more outlets. The existing lines are connected to the "quick connect" holes in the back of the outlet, leaving 2 open terminals on each side of the outlet. Is it okay to connect the third new line to the side terminals, and the new ground wire in with the other two grounds?   So the new setup would consist of this:   2 lines (2 white + 2 black wires) connected through the backwiring holes 1 line (1 white + 1 black wire) connected via the side terminals (black on "long" side, white on "short" side). all three lines' ground wires pigtailed, with the pigtail connected to the one ground terminal on the outlet.


I have assembled an audio amplifier, starting from a cheap tpa3116d2 circuit board. It is powered up by using another cheap step-up circuit to reach 14V (manufacturer suggested 24V). I wanted to dissipate any potential heat by adding a (oversized) vent to the circuit. Both the amplifier + step-up are supplied by a 12v PSU from an old desktop pc. To feel safe that this setup wouldn't burn my house, I had decided to add a fuse on the +12V line between the PSU and the vent+stepup circuit, on a small prototype PCB. I had placed it the closest I could to the 12v connector. I had some 250V rated glass fuses, I had found (by trial and error) that the 0.5A glass fuse does its job (the 0.25A fused as soon as I have turned on the amplifier), and it has protected the speakers from a overcurrent spike by opening the circuit (the amplifier does not turn on properly when the volume is set to high on boot). Do I have to worry about the fact that the glass fuses are 250V and not 12v rated? Are there any factors to take into account when considering fuses?

Anyone knows the very common glass fuses in electronics etc. But I am uncertaion about the breaking conditions.  Example: A fuse rated as 5A/250V, it is the breaking point. But I have seen such used in devices with a much lower voltage, like 12V or 24V.  The breaking of the fuse is based on a maximum energy generated as heat to melt the internal lead by Ohm'S law, aka P = UxI.  But this does not correlate with the current (A) at different voltages. In the example, the nominal is P = 5A*250V = 1.250, which used with a 24V case, would be (I = P/U) = 1.250/24 = 52A which is way beyond the rated 5A.  In other words: We have different currents at different voltages to generate the same energy, if we are to follow Ohm'S law and that the breaking requires the same energy in any case.  This is a little confusing, because it must be the current that are the dominator and the current is driven by the voltage, so the voltage is certainly a factor...


Is it because Einstein described gravity not as a force but as a curvature of spacetime? Physicists usually say that it is hard to combine quantum mechanics with gravity. But I had doubt, is it because of Heisenberg’s uncertainty principle that quantum particles can be at multiple places at once and therefore the gravity associated with the electron (quantum particles) can be at multiple places? Or as Hawking suggested in his book “A Brief History of Time” that when we work to do the math we end up coming up with numerous infinities which does not gets cancelled, but the more successful theory of quantum mechanics also has infinities under singularities but still we call it a successful one, so can’t those infinities get ignored (And what those infinities even mean as no one clearly tends out to show us the math behind it). I strongly suspect that there is an incomplete understanding of quantum mechanics in me as for sure the great physicists cannot be wrong if the is, then can you please explain. Thank you. We all have heard about the genius of Einstein about description of gravity not as a force but as a curvature of spacetime. We have encountered numerous situations in which Einstein’s general and special theory of relativity have provided us with results with extreme precision then why are we searching for a particle associated with gravity when we know that gravity cannot be expressed as a particle as it is the mere bending of spacetime? Your views ..

It is well known that quantum mechanics and (general) relativity do not fit well. I am wondering whether it is possible to make a list of contradictions or problems between them?  E.g. relativity theory uses a space-time continuum, while quantum theory uses discrete states.  I am not merely looking for a solution or rebuttal of such opposites, more for a survey of the field out of interest.


My app is currently trying to connect a user and customer and here I am trying to do this via Firebase and GeoFire. However for some reason this switch is throwing me   2020-03-20 01:13:13.614 14508-14508/swift.fix.application I/Choreographer: Skipped 62 frames!  The application may be doing too much work on its main thread. 2020-03-20 01:13:13.907 14508-14508/swift.fix.application D/AndroidRuntime: Shutting down VM 2020-03-20 01:13:13.935 14508-14508/swift.fix.application E/AndroidRuntime: FATAL EXCEPTION: main     Process: swift.fix.application, PID: 14508     java.lang.NullPointerException: Attempt to invoke virtual method 'int java.lang.String.hashCode()' on a null object reference         at swift.fix.application.TradesmanMapActivity$4.onLocationResult(TradesmanMapActivity.java:180)         at com.google.android.gms.internal.location.zzau.notifyListener(Unknown Source:4)         at com.google.android.gms.common.api.internal.ListenerHolder.notifyListenerInternal(com.google.android.gms:play-services-base@@17.1.0:17)         at com.google.android.gms.common.api.internal.ListenerHolder$zaa.handleMessage(com.google.android.gms:play-services-base@@17.1.0:6)         at android.os.Handler.dispatchMessage(Handler.java:106)         at com.google.android.gms.internal.base.zar.dispatchMessage(com.google.android.gms:play-services-base@@17.1.0:8)         at android.os.Looper.loop(Looper.java:193)         at android.app.ActivityThread.main(ActivityThread.java:6669)         at java.lang.reflect.Method.invoke(Native Method)         at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)         at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)   The app crashes when I select to be a user, and crashes the app. I have looked through to see if I am missing a CustomerID somewhere but can't see anywhere. The stand out is the NullPointerException error.  switch (CustomerID){                     case "":                          geoFireWorking.removeLocation(UserID, new GeoFire.CompletionListener() {                             @Override                             public void onComplete(String key, DatabaseError error) {                              }                         });                         geoFireAvailable.setLocation(UserID, new GeoLocation(location.getLatitude(), location.getLongitude()), new GeoFire.CompletionListener() {                             @Override                             public void onComplete(String key, DatabaseError error) {                              }                         });                          break;                     default:                         geoFireAvailable.removeLocation(UserID, new GeoFire.CompletionListener() {                             @Override                             public void onComplete(String key, DatabaseError error) {                              }                         });                         geoFireWorking.setLocation(UserID, new GeoLocation(location.getLatitude(), location.getLongitude()), new GeoFire.CompletionListener() {                             @Override                             public void onComplete(String key, DatabaseError error) {                              }                         });                          break;                 }   I am not sure what I am missing and it is really bugging me as I assumed it was correct :(

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?


All upgrades in NMS say that they get activated as soon as they are available inside the inventory/suit/cartridge. Though, I have noticed that, suppose, if I put all mining tool upgrades close to each other, they all get a green coloured aura around them.  Does positioning of these upgrade modules also matter in the game? I've noticed that I can not move these upgrades around, unlike other commodities/objects/ores etc. So I thought that there might be this possibility!

So I recently discovered via  that upgrades should be adjacent to the thing they're upgrading (or other upgrades to it). You can see in the image below that the UI will color the border of adjacent upgrades but not ones sitting by themselves:    The post itself is a little unclear how much that helps, and suggests it gives them some sort of bonus, but has no details and is not 100% reliable. Are we sure it gives a bonus, or does the upgrade maybe just not work in the first place if it's not adjacent?  Recently I'd upgraded my jetpack, and while I didn't have a stopwatch out to time it, I wasn't noticing much difference. Then I looked at the text more carefully:    Is this implying that the upgrade won't work unless it's actually adjacent to the jetpack? If so, this seems problematic since when the game starts your jetpack already has things surrounding it and can't be dismantled or moved.   Overall I'm left very unclear on if upgrades must be adjacent to work, and if not, what kind of bonus they get when adjacent.


I have a simple, undirected graph where I'd like to detect "natural" subgraphs where vertices are connected intensively internally but sparsely externally. The problem is that I have no exact hint what could be here "intense" and "sparse", I wonder which graph statistics could give some hints here.  I'm also thinking to apply some kind of clustering on the vertices but no idea how to convert the "closeness" in a graph into feature for a node to apply traditional unsupervised method on these.

I am trying to split a network. I have an adjacency matrix that shows edges between nodes. The weight of the edge depends upon the total number of overlapping items between two nodes/union of items between two nodes.  Next, I am trying to partition this adjacency matrix into sub-networks that show tightness of these sub-networks based on the strength of the connections within them. Right now I am using Networkx python's modularity metric to do this splitting. I am looking for a second opinion. Also, I can keep splitting until the sub-networks further until there are no more sub-networks left.  In addition to that, I am searching for a metric that can tell me whether further splitting this sub-network gives me better information (aka better tighter sub-network than the last one).FYI, this is an unsupervised approach.  Hope this makes sense. If not please fire away your comments/questions and I will edit my response accordingly. Any help is much appreciated.  Rocky


I'm looking to create the following block diagram in Tikz. Any suggestions? Tips?

I'm looking to create something like this in Tikz environment. Any tips? help?


A friend asked me for the time. When I looked at my analog clock (which only has a minute hand and an hour hand, no second hand), I thought of telling her the time with the hour and minute hands swapped, and then have her work out the actual time. Then I realized that not all clock-hand configurations make sense when the hands are swapped. Let $T$ denote the set of all clock-hand configurations on an analog clock that occur over twelve hours. Question: What is the subset of times $S\subseteq T$ such that when the hands are swapped, the time still makes sense? (In other words, $S$ is the maximal subset of $T$ closed under the operation of swapping the hands.) Comments: $S\neq T$, since for example $3:00\notin S$. But $S$ is non-empty, since $12:00\in S$.

At 12 o'clock, the hour hand and minute hand of the clock can be swapped, and the clock still gives the same time, but at 6 o'clock, it can not be swapped. So in what cases when we swap the hour and the minute hand position does a clock still give a valid time?


I recently came across this theorem for the first time.  As I understand it, what she showed was that conservation 'laws' are often simply an artifact of symmetry or invariance.    For example, the source I read said that conservation of momentum flows naturally if all the physics gives the same answer at all places - e.g., Newton's laws are the same here as they are there.  It also said that conservation of energy derives from the laws of physics being invariant over time.  I sort of see the math in the proof, but don't quite get the intuition.  Can anyone provide a brief explanation?

is one of those surprisingly clear results of mathematical calculations, for which I am inclined to think that some kind of intuitive understanding should or must be possible. However I don't know of any, do you?  *Independence of time $\leftrightarrow$ energy conservation. *Independence of position $\leftrightarrow$ momentum conservation. *Independence of direction $\leftrightarrow$ angular momentum conservation.  I know that the mathematics leads in the direction of Lie-algebra and such but I would like to discuss whether this theorem can be understood from a non-mathematical point of view also.


My pc runs a program when it boots. Sometimes the program stops working after a few hours, but it will work fine when it reboots. So, I want to schedule my pc to reboot every 3 hours to prevent the program to be stopped. I'm using Ubuntu 14.04.  edit: The program doesn't stop, it just doesn't work with the maximum power of the pc but I need it to work with full power.

I'm having some periodic issues running a particular application, XBMC. If I use XBMC regularly I don't seem to have any issues but if I leave it unattended for more than about 12 hours I need to reboot to get it working again.  I know a scheduled reboot is NOT the answer but until I can figure out the problem I need to schedule a reboot each morning so my wife can use it if I'm away and it doesn't get thrown out the window :)  Any takers?


My laptop is overheating after installing Ubuntu GNOME16.04 LTS. It's hanging because of overheating. I think that my laptop's cooling system is not working properly and I am unable to find what to do.  sensors:    HTOP:

My PC (Lenovo Ideapad z580) is overheating while running Ubuntu GNOME 16.04 LTS.  $ uname -a Linux Mahadev 4.4.0-72-generic #93-Ubuntu SMP Fri Mar 31 14:07:41 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux  $ lspci -nnk|grep -A2 VGA 00:02.0 VGA compatible controller [0300]: Intel Corporation 3rd Gen Core processor Graphics Controller [8086:0166] (rev 09)   Subsystem: Lenovo 3rd Gen Core processor Graphics Controller [17aa:3977]   Kernel driver in use: i915   $ sensors acpitz-virtual-0 Adapter: Virtual device temp1:        +52.0°C  (crit = +104.0°C)  coretemp-isa-0000 Adapter: ISA adapter Physical id 0:  +54.0°C  (high = +72.0°C, crit = +90.0°C) Core 0:         +54.0°C  (high = +72.0°C, crit = +90.0°C) Core 1:         +54.0°C  (high = +72.0°C, crit = +90.0°C)  update vivek@Mahadev:~$ stress -t 300 -c $(getconf _NPROCESSORS_ONLN) &&  sensors stress: info: [4408] dispatching hogs: 4 cpu, 0 io, 0 vm, 0 hdd stress: info: [4408] successful run completed in 300s acpitz-virtual-0 Adapter: Virtual device temp1:        +73.0°C  (crit = +104.0°C)  coretemp-isa-0000 Adapter: ISA adapter Physical id 0:  +72.0°C  (high = +72.0°C, crit = +90.0°C) Core 0:         +69.0°C  (high = +72.0°C, crit = +90.0°C) Core 1:         +72.0°C  (high = +72.0°C, crit = +90.0°C)  update     vivek@Mahadev:~$ sudo lshw -C cpu     [sudo] password for vivek:    *-cpu                             description: CPU         product: Intel(R) Core(TM) i3-3110M CPU @ 2.40GHz         vendor: Intel Corp.        physical id: 0        bus info: cpu@0        version: Intel(R) Core(TM) i3-3110M CPU @ 2.40GHz        serial: To Be Filled By O.E.M.        slot: CPU Socket - U3E1        size: 1302MHz        capacity: 2400MHz        width: 64 bits        clock: 100MHz        capabilities: x86-64 fpu fpu_exception wp vme de pse tsc msr  pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx  fxsr sse sse2 ss ht tm pbe syscall nx rdtscp constant_tsc arch_perfmon  pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni    pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm pcid    sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer xsave avx f16c lahf_lm    epb tpr_shadow vnmi flexpriority ept vpid fsgsbase smep erms xsaveopt     dtherm arat pln pts cpufreq           configuration: cores=2 enabledcores=2 threads=4  Update This time I edited the sensors , htop command result in image. It's getting overheated, my laptop is getting hang cause of overheating, please watch and reply. Thanks.


Compiler issues: NullPointerException in the line "mass[i].mainN = scan.nextInt();". To my mind, I've inizialized all variables "mainN" and the array "mass". What can be the reason of the exception?  import java.util.Scanner;  public class Robotics{  public static void main(String[] args) {      Scanner scan = new Scanner(System.in);     int N = scan.nextInt();     Robo[] mass = new Robo[N];     for(int i = 0; i < mass.length; i++) {         mass[i].mainN = scan.nextInt();         mass[i].auxiliary = scan.nextInt();     }     scan.close(); }  class Robo{     int mainN;     int auxiliary; }


I'm fiddling out with new Lightning experience. How to get the list of app names available in Lightning Experience App Manager? either using SOQL or APEX or API  this is not duplicate question, what I'm looking is to find out what are the custom objects/components added to this app.  SELECT Id,Name,Type FROM AppMenuItem WHERE Lable = 'test' AND Type = 'TabSet'   below is the attached image.

I would like to query an object that would return the "Created by" date from all custom apps in my org. Is there a way to do this through SOQL?


Is CAN I START correct ?  Is it okay to use it instead of Shall I Start ? For eg I want to start my presentation in front of class  So can I say CAN I START  Like I'm asking for permission to start my presentation. Asking Teacher for permission

Which word to use when we ask for help?  Some conditions:     We know that the person asked is able to do it. We don't know if the person asked is able to do it.


@{     bool a = false;  }      <script>  var element = '<a href="www.testurl.com" + '?a=' + @(a)'; $('#anyElement').append(element);  </script>   The anchor tag will have the href of, www.testurl.com?a=False  In IE11, at least, variable a will be rendered as False instead of false. This causes an ECMAScript error because now the JavaScript/ECMAScript compiler thinks False is an undefined variable.  Why does RAZOR not render this variable in lowercase?

true.ToString()  false.toString();  Output: True False   Is there a valid reason for it being "True" and not "true"? It breaks when writing XML as XML's boolean type is lower case, and also isn't compatible with C#'s true/false (not sure about CLS though).  Update  Here is my very hacky way of getting around it in C# (for use with XML)  internal static string ToXmlString(this bool b) {     return b.ToString().ToLower(); }   Of course that adds 1 more method to the stack, but removes ToLowers() everywhere.


wise Blender-World folks,  I'd like to do a proper simulation of gold foil stickers on glasses (like a decorated long-drink glass).  I am pretty sure about pictures with transparency and stuff that works well on other materials, but blender's glass-material seems to have a mind of its own...  Anyone around who has some hints? That would be awfully nice, thank you so much in advance!  Pls have a nice day.

I'm designing this animal-type creature, and want to add a transparent .png image to its face with the face features (object has a subsurf). On the left is the image with the features, on the right is the part of the object where I want it to be.    I tried to import the image as a plane, but matching the shape of the plane with the face didn't work, and the lines of the face left shadows on the head, and could be seen as a different object from some angles (although it's the closest I've gotten yet). It looked like this:    So , I tried selecting the faces of the head that the features should go over, and create a new material for it. Unfortunately, since the .png is transparent, the result produced was this:    (where it's impossible to tell the transparency from a black background default color, and where I wouldn't know where to start to adjust size and position).  I also tried UV mapping, but then the whole object became black with the features repeated all over.   Is it something I have to go into Nodes for? I'm kind of stuck here. Creating a new material and applying it is simple, but applying a material that is an image is a bit more complex it seems... Ideally, I would reproduce the same technique for the adhesive bandage on its arm (seen on the right of image 1).


I was wondering how can I make an image stay 12mp and 300dpi. I want to participate in a contest about street photography but their requirements are that the image must be 12mp and 300dpi. I'm new to photography and I'm confused about the dpi and the image resolution at 12mp. Also if its okay to shoot at RAW for this case? And would I be able to edit in lightroom the image? I'm using a canon t5i rebel efs 30-135mm.   Thanks guys! Appreciate all the tips and advices.

I am submitting a photo for an exhibit.  They require a jpeg to be evaluated and then a print, if accepted.  The rules indicate "Entries must be in JPEG format sized at 300 dpi on a CD (4” width of image 1,200 pixels at 300 dpi is the largest dimension please)." The final submission will be a maximum of 36" x 36".  I don't see any of this in the photo's properties.  What exactly are they looking for?


public int[][] updateGame(String[] inarr, int c) {    int[][] userGuess = new int[10][4];    for (int i = 0; i < c; i++) {     for (int j = 0; j <= 3; j++) {       userGuess[i][j] = Integer.parseInt(inarr[j]);         System.out.println("user guess in for loop: " + userGuess[i][j]);        //return userGuess[i][j];     }    }    //System.out.println("user guess in method:"+userGuess);    return userGuess;  }   it only returns the address of array

In Java, arrays don't override toString(), so if you try to print one directly, you get the className + '@' + the hex of the  of the array, as defined by Object.toString():  int[] intArray = new int[] {1, 2, 3, 4, 5}; System.out.println(intArray);     // prints something like '[I@3343c8b3'   But usually, we'd actually want something more like [1, 2, 3, 4, 5]. What's the simplest way of doing that? Here are some example inputs and outputs:  // Array of primitives: int[] intArray = new int[] {1, 2, 3, 4, 5}; //output: [1, 2, 3, 4, 5]  // Array of object references: String[] strArray = new String[] {"John", "Mary", "Bob"}; //output: [John, Mary, Bob]


I'm using miktex and there are few packages that I don't have on my pc so I downloaded them , where should I put them to make them functional ( the folder name).

I'm new to LaTeX, investigating using it for some work projects.  I'm using MiKTeX on Windows.  My employer's locked-down network blocks the application's automatic installation function.  I can take my laptop home and successfully install from there, but if I need a package in the middle of the day I'm stuck.  I am able to access the CTAN website and download the package files (.dtx or .ins?), but I don't know what do do with them.  How can I do a manual package installation?


I'm trying to publish my own website with my own bind9 DNS server running in Ubuntu Server 12.04.3 I've registered the domain name example.com.ar in nic.ar  (entity that registers domains in Argentina) delegated to my own dns ns1.example.com.ar ip 200.44.44.244 and ns2.example.com.ar ip 200.44.44.245. I also need to know how to publish those DNS.  I have the following network configuration:  192.168.0.1 GATEWAY1 ext ip 200.44.44.244 FreeBsd PFSense Firewall 192.168.0.6 GATEWAY2 ext ip 200.44.44.245 Debian Iptables Firewall  192.168.2.111 WEBSERVER Ubuntu Server 12.04.3 BIND9+LAMP+DOVECOT  I need to configure WEBSERVER to be able to reach from the internet the websites allocated there from www.example.com.ar I'm having a lot of trouble with DNS zones and records.  I've tried nslookup example.com.ar from the outside of my network but it's unreacheble.  Any help would be appreciated. Thanks.  EDIT 1:  This is my example.com.ar zone:      $TTL    3h     @       IN      SOA     ns1.example.com.ar. admin.example.com.ar. (                               1        ; Serial                               3h       ; Refresh after 3 hours                               1h       ; Retry after 1 hour                               1w       ; Expire after 1 week                               1h )     ; Negative caching TTL of 1 day     ;     @       IN      NS      ns1.example.com.ar.     @       IN      NS      ns2.example.com.ar.       example.com.ar.    IN      MX      10      mail.example.com.ar.     example.com.ar.    IN      A       192.168.2.111     ns1                     IN      A       192.168.2.111     ns2                     IN      A       192.168.2.111     www                     IN      CNAME   example.com.ar.     mail                    IN      A       192.168.2.111     ftp                     IN      CNAME   example.com.ar.   If I just forward my port I'm able to reach the web site by using my external IP address but I can't by its domain name.  EDIT 2:  I still can't make the entity that registered my domain name example.com.ar to reach my server.

I have bought a domain name (without hosting), and at home I have a static ip address on Ubuntu server 11.04. How can I redirect users to my web server at home? What configuration needs to be done?


Sometimes a question may not be very useful but the answer may be. I know that the accepted answer is the most useful one to the OP. But for other users, the most useful answer might be some other answer. Being able to mark that answer as a favorite answer would make it easier to find for future reference.

Lots of questions are very generic, "share an experience" kinds of questions. In these cases, I am quite often interested in specific answers that may not have gotten that many upvotes. These questions also tend to elicit lots of responses, so going back to find the answers I'm interested in somewhere in the middle of a sea of responses is a pain. Is there a way to favorite or bookmark these answers?


The spell description specifically says you can freeze water, but it doesn't mention unfreezing/thawing water that was already frozen or if frozen water counts as water.  Can I use Shape Water to either:   Apply any of the standard effects to an equivalent volume of ice without thawing it? or;    Thaw an equivalent volume of ice (assuming the effect lasts for an hour then the water freezes again).   This question is specifically about using the spell to effect ice. My party is about to head into snowy mountain region and I want to know if I can use it whilst there.

I have been having a discussion regarding the Shape Water cantrip from the Elemental Evil Player's Companion. A friend and I are trying to come to an accurate view of how this spell actually functions.   Some example questions:   Must the targeted water be within a 5 foot cube area, or does it need to be of a volume not exceeding 125 cubic feet? If you shape water that is within a 5 foot cube, can the final shape you animate it to extend outside the cube? Can you cause the shaping to affect ice and snow, or only liquid water? Would you be able to carry a globe of water alongside you over distances?   Really, there are two parts:    What can be targeted by the spell? What are the limitations on the 'shape and animate' portion of the spell?   The answer I am looking for, if possible, would use the language of the spell, possibly with precedent from other game text, to clearly define the limitations of this cantrip.


I'm trying to build a low cost deck, so what cards are there like Flame Imp, Arcane Golem, Leeroy etc.? I couldn't find any related info on the internet.

I'm trying to build a strong deck with minions such as Flame Imp, Arcane Golem, Leeroy etc. that have good stats for their cost, but have downsides. Write down/send links to as many as you know, from any class.


Is there a word that means "somebody who is sponsored"?   E.g. if I sponsor somebody, that person is my ______?  Google results for  have scattered definitions in unreliable sources, so it does not appear that is a real word. I'm looking for something similar, a single word, preferably American English.  The specific context is a social group membership application where new members must be sponsored (as in  - "one who assumes responsibility for some other person or thing") by existing members. I am looking for a single word to describe the target of such a sponsorship.

Google results for sponsee have scattered definitions in unreliable sources, so it does not appear that is a real word. I'm looking for something similar, a single word.  The specific context is a social group membership application where new members must be sponsored (as in definition 2, here - "one who assumes responsibility for some other person or thing") by existing members. I am looking for a single word to describe the target of such a sponsorship. I am about to sponsor a fraternity, but I would like to have a more general word for what I'm sponsoring. Next time, the fraternity could well be a study club, or something else.  Therefore, what is the sponsored party also called? E.g. if I sponsor somebody, that person is my __?


I am an Ukrainina citizen living in Poland. I will be traveling to Thailand but I need to wait at the Dubai airport 9 hours for my next flight back to Poland. I will not be leaving Dubai airport. So in this case do I need a transit visa?

Do I need a transit visa for a layover via airports in the UAE, such as Dubai International Airport or Abu Dhabi International Airport? If so, what are the requirements for such a visa? Can I get the transit visa on arrival?


For example, right now the address is https://superuser.com/questions/ask, so will the "questions/ask" part be leaked?  Other case: https://superuser.com/posts/1385520/edit  Will a hacker know that I'm editing this question?

This is fairly easy.  If I go to https://webserver.com/someurl?a=b, will the someurl?a=b part be protected, or just the contents of the site?


I have always found prepositions to be a fishy part of grammar in English.  Suppose we have a train, a bus, a car, a plane, a ship, a boat.  We can either say:   To get in the train (bus, car, plane, ship, boat). To get into the train (bus, car, plane, ship, boat). To get on the train (bus, car, plane, ship, boat).   But what is the big difference between them.  As I feel it:   "in" shows location and firstly means to get inside of them. "into" shows motion rather than the location. "on" means to board. But you cannot board "a car" for instance, so it doesn't always work.

Examples:   In a car, van, etc. On a bus, boat, motorcycle, etc.   How can one decide which preposition to use? Is memorization the only way or is there a better way?  Note: People generally explain this by either distinguishing between open and closed vehicles or between large and small vehicles. However, the examples I've given defeat both explanations.


I earned a badge on Ask Different. I found out about this via the achievements dropdown while I was hanging out on Science Fiction & Fantasy:     The badge in the dropdown is the icon that comes with the SciFi site design even though it is a badge on a different site. This is confusing, especially on a site like SciFi where the badge design is so distinctive. It makes me think I somehow earned a badge on SciFi for a question I asked on Ask Different.   If I view the dropdown on Ask Different, it looks better:    Badges in the achievements dropdown should either:   Use the icon that corresponds with the site on which the badge was earned (instead of the site you're currently on), or Use a generic icon in all cases (the  or  designs come to mind)

It's so cool that the notification reminds you of the colour of badge you've earned. But I am a little puzzled by the symbols:      Is it feasible to use the symbol from the earned site? At the moment it uses the symbol from the site I happen to be on (as you can see by looking to the left of the dropdown in each case.)


I just found out that when you type Math.pow(5,25) % 5 in the console, it returns 2. This also happens when you first solve Math.pow(5,25) (298023223876953150 % 5 = 2). But that number is clearly divisible by 5, because it is a power of 5...  Has anyone an idea what is going on here?  (I also saw that the outcome of Math.pow(5,25) is wrong, it is 25 higher than the real number, does someone knows how this works too?)

Is this defined by the language? Is there a defined maximum? Is it different in different browsers?


Other than memorizing and documenting each user's credentials, is there way that I can use the Windows Domain Administrator credentials to login to a workstation-user's desktop as if I were them?  I think this is called impersonation, but my searches are finding articles dedicated to running scripts as a particular user, while I need this ability for non-script-administrative purposes.  Sometimes, after hours (for example), I need to see desktops from the User's perspective, and make modifications to aid their work-flows. I have some users who can't find an application unless it is a desktop shortcut! So I need this for stuff like this, and other things too.  Update: I found this question on Server Fault:    None of the answers offered much hope. I guess I'll just have to change the user's password if I don't know what it is an tell them what I changed it to next work-day?  As an admin, I wish I could just login with my admin-credentials to any non-admin user. In Linux, I can do this using the su command.

Is there a way (when logged in as an administrator, or as a member of the administrators group) to masquerade as a non-privileged user? Especially in an AD environment.  e.g., in the Unix world I could do the following (as root):  # whoami root # su johnsmith johnsmith> whoami johnsmith johnsmith> exit # exit   I need to test/configure something on a user's account, and I don't want to have to know their password or have to reset it.  Edit: runas won't cut it. Ideally, my whole desktop would become the user's, etc. and not just in a cmd window.


As indicated above, do we need to hyphenate said words?  The same questions apply to other "country-related terms" like Singapore quality, German precision, etc.  Thanks in advance

Some compound words are written without hyphens (nonaggression, nonbeliever), some with hyphens (well-intentioned), and others with spaces (post office).  Is there a rule or good guide as to which option should be used?


I'm a newbie to Ubuntu.  Is there some way to make Ubuntu compatible with Arabic language?  I don't mean the keyboard layouts  , I mean when open an exiting windows text file it's like this:    But when I create, type, save, re-open the text file Arabic works fine:

I sometimes need to open text files that are encoded in EUC-KR.    man gedit gives:      --encoding           Set the character encoding to be  used  for  opening  the  files           listed on the command line.    This can be used to open specific files with the desired encoding:  gedit --encoding euc-kr readme.txt   However, each file to be opened requires a similar command to be typed.  I can run iconv on the file(s), but then I have to deal with different file versions.    Do I have better options for dealing with non-utf8 text files?


my HDD partition is not opening  (MOON is my HDD partition name)  ERROR  Error mounting /dev/sda4 at /media/praveen/MOON: Command-line `mount -t "ntfs" -o "uhelper=udisks2,nodev,nosuid,uid=1000,gid=1000,dmask=0077,fmask=0177" "/dev/sda4" "/media/praveen/MOON"' exited with non-zero exit status 14: The disk contains an unclean file system (0, 0). Metadata kept in Windows cache, refused to mount. Failed to mount '/dev/sda4': Operation not permitted The NTFS partition is in an unsafe state. Please resume and shutdown Windows fully (no hibernation or fast restarting), or mount the volume read-only with the 'ro' mount option.

Whenever I boot Ubuntu, I get a message that it cannot mount my windows partition, and I can choose to either wait, skip or manually mount.  When I try to enter my Windows partition through Nautilus I get a message saying that this partition is hibernated and that I need to enter the file system and properly close it, something I have done with no problem so I don't know why this happens.    Here's my partition table, if any more data is needed please let me know.     Device Boot      Start         End      Blocks   Id  System /dev/sda1            2048    20000767     9999360   83  Linux /dev/sda2        20002814   478001151   228999169    5  Extended /dev/sda3   *   478001152   622532607    72265728    7  HPFS/NTFS/exFAT /dev/sda4       622532608   625141759     1304576   82  Linux swap / Solaris /dev/sda5        20002816   478001151   228999168   83  Linux


what I mean is that,if you have two objects(one hollow and other solid):  Lets say, a solid sphere and a hollow sphere and if you calculate moment of inertia of the two of them, you would find that moment of inertia is more in the hollow one than in the solid one.  So, is this concept i.e moment of inertia of a hollow object is more than its corresponding solid one always true?   Given:mass of both the bodies are equal  NOTE:THIS ISN'T A DUPLICATE QUESTION,ALL THE PREVIOUS QUESTION EXPLAIN IT FOR A PARTICULAR BODY ,BUT I'M QUESTIONING ITS VALIDITY FOR EVERYTHING(UNIVERSAL OR NOT)

Why is the moment of inertia (wrt. the center) for a hollow sphere higher than a solid sphere (with same radius and mass)? I have completely no idea and I am inquiring about this as it is an interesting question that popped in my head while doing physics homework.


Let $$f :  A \to B, \quad  g: B \to C, $$ be two functions. Show the following:  1) If $f$ and $g$ are surjective then $g \circ f$ is surjective   2) If $f$ and $g$ are bijective then $g \circ f$ is bijective.  3) If $g\circ f$ is injective then $f$ is injective.  4) If $g \circ f$ is surjective then $g$ is surjective.  5) If $g \circ f$ is bijective then $f$ is injective and $g$ is surjective.  How can I prove the following statements ? I assume that I can say that 2) is bijective If I can prove 1) (I know $g\circ f$ is injective)  A little bit help would be awesome thank you...

I'd like to see if these proofs are correct/have them critiqued.     Let $g: A \to B$ and $f: B \to C$ be functions.  Then:   (a) If $g$ and $f$ are one-to-one, then $f \circ g$ is one-to-one.   (b) If $g$ and $f$ are onto, then $f \circ g$ is onto.   (c) If $f \circ g$ is one-to-one, then $f$ is one-to-one?   (d) If $f \circ g$ is one-to-one, then $g$ is one-to-one?   (e) If $f \circ g$ is onto, then $f$ is onto?   (f) If $f \circ g$ is onto, then $g$ is onto?     (a)  Let $a,b \in A$.  If $(f \circ g)(a)=(f \circ g)(b)$, then $f(g(a))=f(g(b))$.  Since $f$ is one-to-one, we know that $g(a)=g(b)$.  And, since $g$ is one-to-one is must be that $a=b$.  Hence $f \circ g$ is one-to-one.    (b) Since $f$ is surjective we know that for all $c \in C$ there is a $b\in B$ such that $f(b)=c$.  Since $g$ is surjective, there is a $a \in A$ such that $g(a)=b$.  Hence, for all $c \in C$ there is an $a \in A$ such that $(f \circ g)(a)=f(g(a))=f(b)=c$.    (c)  This is false.  Let $A=\{1\}$, $B=\{1,2\}$, and $C=\{1\}$. Define $g(1)=1$ and $f(1)=f(2)=1$. Then $f \circ g$ is injective, but $f$ is not injective.    (d)  This is true.  Let $a,b \in A$ where $a \neq b$.  If $(f\circ g)(a)\neq(f\circ g)(b)$, then $f(g(a))\neq f(g(b))$.  Hence $g(a) \neq g(b)$.  (e)  Since $f \circ g$ is surjective, then for every $ c \in C$ there is an $a \in A$ such that $f(g(a))=c$.   Let $b = g(a)$.  Then $b \in B$ and $f(b)=g(f(a))=c$.  Thus $f(b)=c$.  Hence $f$ is surjective.  (f)  Using the same set up as part (c), we have that $g$ is not surjective since there is nothing in $A$ such that $g$ will go to 1.


I set up a clean Ubuntu 14.10 and am wondering why I can't use the tabulator key on the keyboard to jump between input fields for server, user, ...

I upgraded 14.04 to 14.10. I installed my apps(lamp, nodejs, filezilla, phpstorm, git etc.). I have some input problems in some apps.  In Filezilla,   I can't use tab and delete keys Some UI problems, in filezilla tabs   In Gedit,   After 2-3 minute I can't write anymore. (Old keys writing sometimes) (No keyboard problem) (I think GTK or RAM problem)


I am working with polynomials in the ring $\mathbb{Z}[X]/(X^n-1)$, so only polynomials with degree at most $n-1$ are allowed, and multiplications must be reduced modulo $X^n-1$. The thing is that I have a polynomial $f(X)$ and I want to compute its inverse modulo an integer $p$, $f_p(X)$, such that $$ f * f_p \equiv 1 \bmod p $$ How could I do that? Any known algorithm? I have heard about the extended Euclidean algorithm, but I'm not quite sure how to use it, for example, given $f(X) = -1+X+X^2-X^4+X^6+X^9-X^{10}$.

Let $\theta$ be a root of $p(x)=x^3+9x+6$, find the inverse of $1+\theta$ in $\mathbb{Q(\theta)}$.  So problems like this really annoy me but I did crappy on the last homework after making a lot of arithmetic mistakes so I want to run everything by you guys. This one isn't actually for homework it's just a suggested practice problem but okay lets go!!!  So I'm not sure if the method I used to do this was standard or not, I don't remember my professor showing me, but what I did first was used the canonical euclidean algorithm in $\mathbb{Q[x]}$ and wrote:  $x^3+9x+6$  $=(1+x)(x^2-x+10-\frac{4}{x+1})$  $=(1+x)(x^2-x+10)-4$  the reduced modulo  the minimal polynomial of $\theta$ i.e. $x^3+9x+6$ and so  $4=(1+x)(x^2-x+10)$  $\rightarrow$  $1= \frac{1}{4}(1+x)(x^2-x+10)$ and sooo ah $(\theta^2-\theta+10)\frac{1}{4}$ is what I believe is the inverse of $(1+\theta)$ in the quotient field... Like i said I hate these problems but ehh is this correct? On a lighter note it's finally getting cool enough for me to go on proper runs here and so that's pretty bomb!


I am very beginner at coding and most the answers I have come across have just gone straight over my head. The only code I have to make my slideshow work (which it is working) is:  <script type="text/javascript"> <!--> var image1=new Image() image1.src="congo.jpg" var image2=new Image() image2.src="snow.jpg" var image3=new Image() image3.src="mekong.jpg" //--> </script>   and in the body section:  <img src="congo.jpg" name="slide" width="400" height="300"> <script type="text/javascript"> <!-- var step=1 function slideit(){ document.images.slide.src=eval("image"+step+".src") if(step<3) step++ else step=1 setTimeout("slideit()",2500) } slideit() //--> </script>   I have no clue how to center this or put in a margin. I tried placing it within a table so I could manipulate its location, which didn't work (assuming it's just not that easy), and tried messing around with a  tag to center but I was just pulling at strings! What is the proper way to add margin/center? Thank you.

How can I horizontally center a
 within another
 using CSS?

Foo foo


I noticed this trend in Wolfram Alpha for that $x-y$ divides $x^3-y^3, x^5-y^5, x^7-y^7$ so I was wondring if it is true for all $ k \in \mathbb{N}$?

I did some mathematical induction problems on divisibility   $9^n$ $-$ $2^n$ is divisible by 7. $4^n$ $-$ $1$ is divisible by 3. $9^n$ $-$ $4^n$ is divisible by 5.   Can these be generalized as $a^n$ $-$ $b^n$$ = (a-b)N$, where N is an integer? But why is $a^n$ $-$ $b^n$$ = (a-b)N$ ?  I also see that $6^n$ $- 5n + 4$ is divisible by $5$ which is $6-5+4$ and $7^n$$+3n + 8$ is divisible by $9$ which is $7+3+8=18=9\cdot2$.  Are they just a coincidence or is there a theory behind?  Is it about modular arithmetic?


If $A$ and $B$ are two different complex numbers and $|B| = 1$, find the value of   $$\frac {|B-A| }{|1-\overline AB|}$$   where, as usual, $\overline A$ denotes the conjugate of $A$.   If possible please don't tell me the entire answer just tell me from where to begin.

If $z_1$ and $z_2$ are two different complex numbers and $\lvert z_1\rvert=1 $ then find  $$ \frac{\lvert z_1-z_2 \rvert}{\lvert 1-z_1\bar{z_2} \rvert} $$


So I have a small Vue.js project that displays 6 objects of "Ninjas" and when I click on the button toggle it suppose to toggle the "ninja's speciality":   <template>

{{x.name}}

{{x.speciality}}
       <button v-on:click="toggle(x.show)">Toggle</button>

 </template>       The problem is that the toggle function isn't working properly because when I click on the button it doesn't the show property of the given object (The first log is false then it changes to true however when I run it again the show property hasn't been changed to true it is false again).  However when I change the code from this:  <button v-on:click="toggle(x.show)">Toggle</button>   To this:  <button v-on:click="toggle(x)">Toggle</button>   And when I change toggle method to this:  toggle: function (n) {             console.log(n);             if(n.show===true) n.show=false;             else if(n.show===false) n.show=true;             console.log(n);           }   The program works properly.   Can anyone explain to me why the first time it doesn't work and the second time it works?  Thank you!

The primitive types (number, string, etc.) are passed by value, but objects are unknown, because they can be both passed-by-value (in case we consider that a variable holding an object is in fact a reference to the object) and passed-by-reference (when we consider that the variable to the object holds the object itself).  Although it doesn't really matter at the end, I want to know what is the correct way to present the arguments passing conventions. Is there an excerpt from JavaScript specification, which defines what should be the semantics regarding this?


I remember a story that deals with humans on Earth having some sort of long-term, long-distance interaction (perhaps war/conflict, but I think they were benevolent in some way; but I can't remember) with aliens, but over the course of those years or decades, no human ever saw one of the aliens. I remember the end being sort of a twist ending:  The story ends with the aliens landing on Earth and when the first one disembarks from their ship, we see they look a whole lot like the traditional image of a red devil with horns and a tail. They stayed hidden for so long because they were aware of the iconic devil image and didn't want us to associate them with the devil.  I don't know if this was a short story or novel. It may have been part of a collection of books a friend loaned me during the early to mid 1990's to broaden my SF/F perspectives; he included a lot of military fiction and some fantasy, both of which I hadn't read much. I've tried searching online using key terms but I have been unable to identify the story.

This is a sci-fi book where aliens arrive on Earth and push Earth towards world peace, but refuse to reveal themselves physically. When the aliens finally do show themselves, we find that they       look like .   I recall that the aliens seemed benevolent, but that humanity did not like the direction they were being told to go. I cannot remember the ending or if the aliens turned out to be truly benevolent.


i'd like very much your help with this one :   given a positive function meaning $$ f(x) \geq 0 $$ and $f$  is continuous.  Let $$ M = \sup(f(x)) $$ where $x$ belongs to $[a,b]$.  How can i prove that  $$\lim_{n\rightarrow\infty} \left[\int_a^b (f(x))^n \, dx\right]^\frac{1}{n}  = M$$

Show that $$\sup_{x\in [a,b]} f(x) = \lim_{n\rightarrow\infty} \left(\int_a^b (f(x))^n \;dx\right)^{\frac{1}{n}}$$ for f continuous and positive on [a,b].  I can show that LHS is greater than or equal to RHS but I can't show the other direction.


I am facing a very strange problem. I have written the below code.      if (verifiedStatus.equals("1")) {     imageView.setImageResource(R.drawable.ic_verified_user_black_24dp);     }      else if (verifiedStatus.equals("0")) {     imageView.setImageResource(R.drawable.ic_not_interested_black_24dp);     } else {}   As the code runs, if the value is 1, first the verified image comes but later it changes to the not interested image. I tried debugging and I saw that the code goes into an internal file/code and in the below lines, it changes the image to the other image.  for (;;) {     Message msg = queue.next(); // might block     if (msg == null) {         // No message indicates that the message queue is quitting.         return;     }   Can someone help me in resolving this issue?

I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?


I needed to create a list of lists in Python, so I typed the following: my_list = [[1] * 4] * 3  The list looked like this: [[1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1]]    Then I changed one of the innermost values: my_list[0][0] = 5  Now my list looks like this: [[5, 1, 1, 1], [5, 1, 1, 1], [5, 1, 1, 1]]    which is not what I wanted or expected. Can someone please explain what's going on, and how to get around it?


Let $X_{n}, Y_{n}$ be independent martingals. Is it also the case that $X_{n} + Y_{n}$  is a martingale? And if we drop the independence condition does ist also define a martingal?

Given two Martingale processes $(X_t)$ and $(Y_t)$, are their sum $(X_t+Y_t)$ and their product $(X_t \times Y_t)$ also Martingale?  If not, will the two $(X_t)$ and $(Y_t)$ being independent grant their sum and product Martingale? Thanks!


Question: Prove that if S is a countably infinite set then all the finite subsets of S are also countably infinite.   Where would I start?

Show that the set of all finite subsets of $\mathbb{N}$ is countable.   I'm not sure how to do this problem. I keep trying to think of an explicit formula for 1-1 correspondence like adding all the elements in each subset and sending that sum to itself in the natural numbers, but that wouldn't be 1-1 because, for example, the set {1,2,3} would send to 6 and so would the set {2,4}.  Multiplying all the elements in each subset and sending that product to itself in the natural numbers wouldn't work either since, for example, {2,3} would send to 5 and so would the set {1,5}. Any ideas?


Would I say:  What follows is the Xs... What follows are the Xs...  or something else? In my case X is a table.

Which sentence is more grammatically correct?     He is being tried on what look like trumped-up charges.   He is being tried on what looks like trumped-up charges.


If someone who is recently having chickenpox (2-3 day) ,comes in contact with me (I have already had it in past). Can the virus comes in my body again? Most importantly can virus enter in to third person through me?

My 3-year-old has had chickenpox for about 2-3 days, but a close friend has just had a baby and I want to go and help. Is it possible that I am infectious, despite not having the illness? I had it as a child, so (hopefully) can't actually get it myself. Thanks!


A friend handed me a logo file with an RGB color of #BA00FF. I'm having trouble finding an exact CMYK match for the bright purple color.  Any help appreciated.

I designed a poster in CorelDraw X5 for printing purposes. I was told by the Printshop guy to use colors only in CMYK. For the most part I did, I don't know why I missed it but I used one color in RGB. I liked this color so much that I've used it at many places. So, current situation is that some colors are in RGB and some are in CMYK. So, I want to convert all RGB to CMYK and thought the problem would be solved. But now I'm actually facing a lot of trouble. The colors are not at all same. I hate the colors that it is showing me.  This is the color I used in RGB:    When I changed the "Model" to CMYK, the color it shows is really different. As you can see in the picture below, it's too dull:    The RGB values of both colors are not the same. What can I do to get the same color in CMYK? I did a little bit of reading here and there. They say, that you can't get same. In that case, what is the closest color that I can get?


Kenobi wanted to fight Palpatine as he couldn't stomach the thought of fighting Vader ("as he was a brother").  Yoda dismissed the idea as he knew Kenobi was too weak.  Yoda decided he would fight Palpatine and Kenobi against Vader.  Was he just overconfident?  He thought Kenobi could take care of Vader and he could take care of Palpatine?  Wasn't choosing to 1v1 Vader and Palpatine the extremely risky choice?  What if they both died (Yoda and Kenobi)?  Then what?  Wouldn't the more logical and less risky decision be to jump Palpatine? Then take care of Vader together after?  Or even less risky, jump Vader and double-team Palpatine later?  Either-way I say the most logical choice was to double team one of them (Vader or Palpatine), then regroup, maybe collect a couple other jedi survivors and jump the remaining one.

In Revenge of the Sith, Yoda and Obi-Wan split up to confront Palpatine and Skywalker in single-combat. However, with the millions of lives at stake, and the obvious power of the Emperor with his immense skill in the force, and the massive armies at his disposal, wouldn't it have been better and safer to confront Palpatine together? With Anakin on a mission to Mustafar, he wouldn't be around to help Palpatine, and can be dealt with later.   This is especially so given that Mace Windu, widely regarded , whose  fighting style draws on the Darkness of the opponent and becomes even more effective against a Sith, attempted Palpatine's arrrest with two other accomplished Jedi Masters.   Yoda and Obi-Wan are also affiliated with the light side of the force and shouldn't be as susceptible to raw emotions like pride. In this sense, Palpatine appears surprisingly accurate when he tells Yoda that .


I've got a bunch of randomly-sized pillars and they are all connected. I want to create an even gap between all the pillars, almost like a city. I can't find a way to accomplish this.

If I have multiple objects selected can I use scaling to make the objects closer together (without rescaling the objects)?


IIANM, bash saves its history to ~/.bash_history (or to $HISTFILE) on exit from a login shell session. But - what if you want to occasionally persist it for fear of the shell getting prematurely killed (as in SIGKILL or power failure)? Is this possible without burdening the system or the shell session experience?

Following the :     When closing multiple bash instances at the same time, there is a   known race condition that may cause the history to be cleared. This   occurs because there is no locking used when the bash history file is   written.   How can I prevent against this cause of bash history purge?  I use i3wm and I think that it happens mostly when I shutdown the computer before I manually close urxvt terminals. The command used (via keybind) for shutdown is systemctl poweroff.


While my textbook explicitely writes down the mean and variance of the simple regression coefficients, I am interested in knowing $\text{Var}(\beta_0 + \beta_1 x)$ for a fixed $x$. My attempt is to write $$\text{Var}(\beta_0 + \beta_1 x) = \text{Var}(\beta_0 )+xVar(\beta_1)+x\text{Cov}(\beta_0, \beta_1)$$. Yet I am stuck trying to figure out how to compute the covariance term. I would appreciate thoughts on how to calculate this quantity.

I am reading a book on linear regression and have some trouble understanding the variance-covariance matrix of $\mathbf{b}$:    The diagonal items are easy enough, but the off-diagonal ones are a bit more difficult, what puzzles me is that  $$ \sigma(b_0, b_1) = E(b_0 b_1) - E(b_0)E(b_1) = E(b_0 b_1) - \beta_0 \beta_1 $$  but there is no trace of $\beta_0$ and $\beta_1$ here.


I'm trying to use jdbcTemplate to execute sql commands. In this case, I'm trying to insert things into a table. I'm getting a null pointer exception in the line : jdbcTemplate.execute(subscriptionStatusInsertQuery);  When I try to run the line: dbMapper.mapToDatabase(newEntry); where dbMapper is an instance of DBMapper.  @Repository public class DBMapper {      private JdbcTemplate jdbcTemplate;      public JdbcTemplate getJdbcTemplate() {         return jdbcTemplate;     }      @Autowired     public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {         this.jdbcTemplate = jdbcTemplate;     }      public void mapToDatabase(Status status) {         String id = status.getId();          String subscriptionStatusInsertQuery = "INSERT INTO t1 (ID) VALUES (id)";         jdbcTemplate.execute(subscriptionStatusInsertQuery);     } }   I've tried not having a setter for jdbcTemplate. I've tried taking out the @Repository annotation. I've tried having a setter that included datasource. Still getting error.  How should I fix this null pointer exception?  Edit:  My application.properties has the following setting:  spring.datasource.url=jdbc:mysql://localhost:3306/ee_internal spring.datasource.username=ee spring.datasource.driver-class-name=com.mysql.jdbc.Driver spring.datasource.password=mypassword spring.datasource.test-on-borrow=true spring.datasource.validation-query=SELECT 1   And from my pom.xml:  <dependency>             <groupId>org.springframework</groupId>             <artifactId>spring-jdbc</artifactId>         </dependency>

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?


I am using this code to disable wordpress default jquery and load from Google library to speed up website and reduce latency for this Big File.  But Here i want to make it defer or async loading, So How we can do this ?  Here is code which i am using in my function.php file:-  //Making jQuery to load from Google Library function replace_jquery() {     if (!is_admin()) {         // comment out the next two lines to load the local copy of jQuery         wp_deregister_script('jquery');         wp_register_script('jquery', 'http://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js', false, '1.11.3');         wp_enqueue_script('jquery');     } } add_action('init', 'replace_jquery');   I have tried this in my functions.php, but it does not work:  add_filter( 'script_loader_tag', function ( $tag, $handle ) {      if ( 'jquery/1.11.3/jquery.min.js' !== $handle )         return $tag;      return str_replace( ' src', ' async="async" src', $tag ); }, 10, 2 );

I couldn't add defer tag in plugin javascripts. Google developer pagespeed test suggests me to add defer tag in contact form 7 javascripts.   This is how contact form 7 includes javascript in header.  add_action( 'wp_enqueue_scripts', 'wpcf7_enqueue_scripts' );  function wpcf7_enqueue_scripts() {     // jquery.form.js originally bundled with WordPress is out of date and deprecated     // so we need to deregister it and re-register the latest one     wp_deregister_script( 'jquery-form' );     wp_register_script( 'jquery-form', wpcf7_plugin_url( 'jquery.form.js' ),         array( 'jquery' ), '2.52', true );      $in_footer = true;     if ( 'header' === WPCF7_LOAD_JS )         $in_footer = false;      wp_enqueue_script( 'contact-form-7', wpcf7_plugin_url( 'scripts.js' ),         array( 'jquery', 'jquery-form' ), WPCF7_VERSION, $in_footer );      do_action( 'wpcf7_enqueue_scripts' ); }   Now how to add defer="defer" tag in the above code?


Scenario: Bases loaded, two out. A ground ball is hit to third base. The runner from third crosses home plate before the runner from second is tagged out on their way to third base. Does the run count?

There is a runner on third with two out. Batter hits a slow roller to first base. First baseman charges and picks up the ball. Runner from third crosses home. First baseman tags the runner running from home to first, does the run count ?


In previous versions of Ubuntu (16.04, 18.04) I renamed the files on the desktop using the F2 hotkey. But in Ubuntu 20.04 I can't do this. This is possible only by right-clicking mouse on the file and selecting the "Rename" option that is very inconvenient. How to make the system allow me to rename desktop files using a hotkey?  I also tried to find something on Google, but I did not find anything useful.  But in nautilus I can rename file using hotkey.

I just did a clean install of 20.04 and I noticed that no key shortcuts for files manipulation work when my focus in on Desktop (not in Nautilus).   When I have copied a file to clipboard, I cannot Ctrl+V it to Desktop, when I click on a file on Desktop, I cannot Ctrl+C it, or I cannot Delete it with keys. Only ways to do it is either navigate to the Desktop folder in Nautilus, or right-click the file on the Desktop and copy/move to trash/paste...  Sorry if I'm missing something obvious, all the key shortcuts worked normally for me in 18.04.


I'm working on making a ledger app that shows transactions. The focus is always on a single ledger, so transactions have a positive or negative amount, which raises or lowers the ledger's balance. However, we have a hard reference to the "other party ledger," to which, or from which money moved. I'm having a hard time coming up with a word for the header that describes this column, since it could be the payee or the payer. E.g.,     Date Description ???? Amount Running Balance     2021-01-01 Initial account funding checking account 1234 +100 100   2021-01-02 Transfer to John Doe john.doe.1234 -50 50   2021-01-03 Transfer from Jane Doe jane.doe.5678 +25 75     I'd like to avoid using the word "account" since it has a different meaning elsewhere in the app, and "Payer/Payee" seems confusing since it doesn't indicate when one applies vs the other.

I am looking for a word or term that encapsulates both the payor and payee. ideally it would be used in a bookkeeping context.  Example:      Company X both receives and and sends payments to company Y. In the bookkeeping transactions they are ....   Please, do not feel limited to the example given.