I need to look into an issue with an old version of a Debian package <pkg>, and would like to download it in both binary and source forms. A quick apt-cache show <pkg> just displays the most recent versions of <pkg>, but not a complete history. Is there a way to display the version history of <pkg> using APT?

I am trying to install the latest version of subversion on Sid, and because it has a bug I receive a warning and I abort the installation. How do I get to locate the previous version version, install it and pin until the bug is resolved?  root@server01:~# apt-get install subversion   Reading package lists... Done                                                                                Building dependency tree                                                                                Reading state information... Done                                                                                Suggested packages:                                                                                db5.3-util subversion-tools                                                                                The following NEW packages will be installed:                                                                                subversion                                                                                0 upgraded, 1 newly installed, 0 to remove and 205 not upgraded.                                                                                Need to get 0 B/981 kB of archives.                                                                                After this operation, 4,844 kB of additional disk space will be used.                                                                                Retrieving bug reports... Done                                                                                Parsing Found/Fixed information... Done                                                                                critical bugs of subversion (-> 1.9.2-2) <Outstanding>                                                                                b1 - #803725 - subversion: dump-load of a repository modifies verbose log output: M line lost serious bugs of subversion (-> 1.9.2-2) <Outstanding>  b2 - #803589 - FTBFS with ruby2.2 (only) Summary:  subversion(2 bugs) Are you sure you want to install/upgrade the above packages? [Y/n/?/...] n ********************************************************************** ****** Exiting with an error in order to stop the installation. ****** ********************************************************************** E: Sub-process /usr/sbin/apt-listbugs apt returned an error code (10) E: Failure running script /usr/sbin/apt-listbugs apt


I'm new with unity and c#. I have a class with subclass as below. Now I want to add new data inside the list of friends.  [Serializable] public class PlayerData {     public string playerName;     public string playerId;     public Friend[] friends; }  [Serializable] public class Friend {     public string playerName;     public string playerId; }   I want to add new friend in the friend class list. Code I have tried till now.  public string AddFriends(string friendId)     {         PlayerData pd = playerDataDict[playerId];         Friend friend = new Friend();         friend.playerId = friendId;         pd.friends.Append(friend);         return "sdwsd";     }   Thank you

Probably a really simple one this - I'm starting out with C# and need to add values to an array, for example:  int[] terms;  for(int runs = 0; runs < 400; runs++) {     terms[] = runs; }   For those who have used PHP, here's what I'm trying to do in C#:  $arr = array(); for ($i = 0; $i < 10; $i++) {     $arr[] = $i; }


I use emacs as an editor in the command line (aliased with alias em='emacs -nw') and would like to be able to make an alias for !em to open up the file most recently opened in emacs.  I've tried alias e='!em', alias e='${!}em', alias e='${!em}', but so far can't find anything that works.   I've found some related posts about aliasing !!:

I'm trying to set an alias for sudo !! in Bash. I tried alias sbb='sudo !!', but it interprets that as a literal  !! and prints   sudo: !!: command not found   If I use double quotes, it substitutes the double bang in the string itself, so that doesn't work.  Is there any way to make this work? Or an alternative alias? `


I have a macbook pro late 2011.  At this moment I am running the basic 2x 2GB 1333MHz rams ,but I want to upgrade.  Now,I have read on some forum that this macbook can run 1600MHz rams even though Apple sold it with 1333MHz rams.  Any ideas what's up with this?I am a bit confused at this point as I don't know what to buy.  Also, are Kingston memory sticks good?I had a kingston SSD a few months ago and it was just great ,but don't know about rams.

I bought a Mac (13", early 2011) almost 5 years ago. When I first got it, it was running under OS X 10.7 and it was pretty fast. I've being upgrading it ever since and it's now running under Mac OS X 10.11.  I guess it didn't totally survive the upgrades because, today, there's a lot of bugs, freezes, lags, "spinning beach ball" appearing,... for example, when I write something on a normal program/editor, the cursor freezes for a few seconds, then catches up to what I'm writting.  As you can guess, that's really annoying! I've been thinkning about upgrading the hardware but I don't know what to do: should I change the RAM to 8 GB - 1 333 MHz (currently my computer has 4 GB - 1 333 MHz)? Or should I upgrade to an SSD (which is pretty expensive and difficult to install)?  Thank you very much.


We define the set:   $$\mathbb{Q}[\sqrt[3]2]=\{a_{0}+a_{1}\sqrt[3]{2}+a_{2}\sqrt[3]{2^{2}}:a_{0}, a_1,a_2\in\mathbb{Q}\}$$  It's easy to prove all the properties of fields, except for the unit elements.  So, how can we prove that $$\forall x\in\mathbb{Q^{*}}[\sqrt[3]2],\exists x^{-1} \in\mathbb{Q}[\sqrt[3]2]:xx^{-1}=1$$   And how can we prove this in general for the set $$\mathbb{Q}[\sqrt[n]2]=\{a_{0}+a_{1}\sqrt[n]{2}+a_{2}\sqrt[n]{2^{2}}+...+a_{n-1}\sqrt[n]{2^{n-1}}:a_{0}, a_1,a_2,...,a_{n-1}\in\mathbb{Q}\}$$

I need to rationalize $\displaystyle\frac{1}{a+b\sqrt[3]2 + c(\sqrt[3]2)^2}$  I'm given what I need to rationalize it, namely $\displaystyle\frac{(a^2-2bc)+(-ab+2c^2)\sqrt[3]2+(b^2-ac)\sqrt[3]2^2}{(a^2-2bc)+(-ab+2c^2)\sqrt[3]2+(b^2-ac)\sqrt[3]2^2}$  But I fail to see the motivation behind this.  Can someone give a more general explanation of how to come to this expression?


Please help me to input a symbol like >---<.   It is like \leftrightarrow but \leftrightarrow is <--->.

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?


Canadian universities have Faculty of Graduate Studies for supporting graduate programs and students. However, I do not under stand how it can operates without conflicting overlap with the technical departments/faculties.  For example, someone is a student in Department of X, Faculty of Y. His academic and official matters are normally within the Department/Faculty. Now with the presence of Faculty of Graduate Studies, how is dealing with other different academic units?   How is the role of Faculty of Graduate Studies in parallel with the technical Department/Faculty? Is there an equivalent system in the US or UK (an other European) universities too?

Specifically, why do some universities have a defined "graduate school" and associated "graduate faculty," with separate appointment process, and some do not, even when they offer many graduate programs?  What is the organizational and administrative thinking behind this?


The L3fp package proposes the range of randint parameters to be +- 10^16 - 1; yet, I seem to be restricted to +-2^31 - 1, any value above it produces the Number too big compilation error. On the other hand I am getting the expected full 16-decimal digit accuracy for fp values. Why?  \documentclass{article} % RN. 15 April 2017 % BRIEF DESCRIPTION: %======================= \usepackage[check-declarations]{expl3} \usepackage{xparse} %----------------------- \ExplSyntaxOn \int_new:N \l_rn_someInteger_int \fp_new:N \l_rn_someFp_fp \NewDocumentCommand\mySetInteger{m}   {     \int_set:Nn \l_rn_someInteger_int {#1}     some~integer:~\int_use:N \l_rn_someInteger_int\\     \int_set:Nn \l_rn_someInteger_int {\fp_eval:n {randint(#1)}}     some~random~integer:~\int_use:N \l_rn_someInteger_int\\     \fp_set:Nn \l_rn_someFp_fp {\fp_eval:n {rand()}}     some~random~real:~\fp_use:N \l_rn_someFp_fp\\     -------------------------------------------\\   } \ExplSyntaxOff %----------------------- \begin{document}     \mySetInteger{1234}     \mySetInteger{2147483647}  %   \mySetInteger{2147483648} %   \mySetInteger{9999999999999999} \end{document}

I am using counters to save positive integers, something like that:  \setcounter{mycoutervalue}{59}   Is there any limit in the value I can save in a counter, in this case mycountervalue? And what is the exact limit?  Thanks! I do not want to get an unexpected overflow.


When cutting a 1-1/8" to 1-1/2" carbon steer tube, what is the maximum length you can leave outside the head tube and the stem clamp? Is there a maximum? How would you determine what the maximum steer tube length for you frame could be? Does it make a difference if the steerer is 1.5" on the bottom?

I'm building my first road bike, which means I'll have to find appropriate bar height through personal experience and cut the fork steerer in process at least once. I plan to start with the following combination, from down to top:    8mm conical spacer that came with headset. 20mm and 10mm spacers. 40mm high stem. 5mm spacer.   In summary, 38mm before stem, 5 after, resulting in total of 83mm of exposed steerer after cut. The fork has 1 1/8 inch (~28mm) tapered carbon fibre steerer, without metal liner inside. Headset is integrated, upper bearing is almost flush with head tube.  Will it be safe or I'll have to cut shorter? Fork manufacturer did not answer the question. I do not plan to ride out of saddle too much, at least during initial fitting, so bars won't experience significant load, and I'm pretty lightweight.


That  says     Exploratory Data Analysis (EDA) is an approach to analyzing datasets to summarize their main characteristics. It is used to understand data, get some context regarding it, understand the variables and the relationships between them, and formulate hypotheses that could be useful when building predictive models.     Both "to doing" and "to do" are used in this sentence, "an approach to analyzing datasets to summarize their main characteristics".  By "to doing" and "to do", I mean "to analyzing" and "to summarize" respectively.  I know "doing (in this case, analyzing data sets)" is a gerund that could be the subject or object of sentences, but when should I use "to doing"? This kind of usage confuses me, so I searched these keywords.  This  discussed "to doing" but didn't give a doable guide when to use which. I guess that's why the asker didn't mark any of the answer as accepted.  Leave a general talking alone, consider this particular case, is that tutorial use "to doing" the right way? When should I use "to doing"?  Note: I am asking what situation should I use "to doing" rather than what is gerund.

Some verbs are followed by ing, e.g. I enjoy swimming. We can't say I enjoy to swim. Likewise, some verbs are followed by to, e.g. I decided to make a plan.   Which particular verbs are followed by ing and to? Can you please provide a list for that?  Moreover, which verbs can be followed by both without having the meaning changed?


I have used Ubuntu for a while and want to find a way to give back to the community and help Ubuntu get better; is there a team in the Ubuntu community that is dedicated to helping users transition from user to contributer?

I would like to know what kinds of contributions someone can make to Ubuntu. Such as Programmer, User, Proofreader, etc.


I made a suggested edit here:   removing the iPhone tag as the question didn't relate to iPhone. The edit was rejected by "Community", but the same edit was made later () by   Just wondering why my edit to remove the tag wasn't good enough, while Geoffroy's was?

Why does the Community user sometimes approve or reject edits? How does a machine know if my edit is valid? What does it mean if my edit was rejected by Community?     See also:


I wanted to make a file read-only (440)in internal storage but it shows "failed",as it seemingly requires root permission but I can't unlock bootloader as of now so is there any means we can do the above task?

I have a rooted OnePlus One running LineageOS 15.1 (Oreo 8.1).  I am trying to adjust some file permissions/ownerships on the emulated sdcard partition. The partition seems to be mounted as an sdcardfs:   A0001:/ # mount | grep /storage/emulated                                                                                /data/media on /storage/emulated type sdcardfs (rw,nosuid,nodev,noexec,noatime,fsuid=1023,fsgid=1023,gid=1015,multiuser,mask=6,derive_gid)   I'm not sure what that means. Some people suggest that Android used to use mount then switched to fuse and now with Oero uses sdcardfs.  I'm not sure if that makes any sense, but I'm a bit scared that something like mount -o remount, rw /mnt/sdcard/ (which apparently is what you had to do in the past to be able to set file permissions on the emulated sdcard partition).  Short demonstration showing that file permissions won't be applied:  A0001:/ $ su A0001:/ # ls -la /storage/emulated                                                                                total 12 drwx--x--x  4 root sdcard_rw 4096 2018-07-24 17:44 . drwxr-xr-x  4 root root        80 2018-07-24 17:21 .. drwxrwx--x 14 root sdcard_rw 4096 2018-07-24 17:20 0 drwxrwx--x  2 root sdcard_rw 4096 1970-01-01 01:12 obb A0001:/ # touch /storage/emulated/a A0001:/ # ls -la /storage/emulated/a -rw------- 1 root sdcard_rw 0 2018-07-24 17:44 /storage/emulated/a A0001:/ # chmod 777 /storage/emulated/a A0001:/ # ls -la /storage/emulated/a                                                                                -rw------- 1 root sdcard_rw 0 2018-07-24 17:44 /storage/emulated/a   (Note: the same happens if I use /storage/emulated/0 instead of /storage/emulated)  My question is: What do I have to run in order to be able to change the file permissions and file ownerships on this weird sdcardfs partition.


On the beta , I can "Recommend Deletion" of answers. It currently doesn't do much, just .   To me, deleting a post is pretty serious stuff, so if I "recommend" such an action, I'd like to be able to track the post. I've been doing this by raising "Not an answer" flags, and keeping track of the posts from my Flagging Summary page. Moderators usually handle those flags pretty fast. And seeing if my flags were helpful or not is valuable feedback to me for deciding how to act on future posts.  But, you cannot flag from the Low Quality review queue, and the posts you Recommend Deletion on simply vanish after you click the button and confirm. I understand the beta tool wants to keep things more simple and focused, and probably also reduce the load on moderators. That's great! But we should have a way to track the posts we Recommend Deletion on.  I was thinking it could be shown on activity > reviews, together with the suggested edits:    The red answer link would indicate a deleted answer so we can easily spot them. If I Recommend Deletion, and it's still blue after a while, I go back there and flag it.  Do you think that could work? Or maybe we should just have a regular flag link on the Low Quality Posts task, like in ?    UPDATE  So now the activity tab on my profile is logging more review actions, such as "Close", "Edit" (improve), "Edit" (from low the quality posts task), and "Looks good". But no sign of "Recommend deletion". Will that be added too?

This post is an expansion of  For many graduated sites (eg Physics), moderators do not want to apply the unilateral close vote in all cases--it is better to let some community votes pile on first.  We only use the unilateral in obvious cases then. This renders the CV queue useless to us. If we "skip" something, we can't get back to it. If we say "do not close", it's removed from the queue and our community can't see it. If we use "close", we are using a unilateral mod vote--we don't want to do that. What I propose is a set of "next/previous" buttons, that let us navigate the queues, looking for closeable questions, and coming back to the others later. Thoughts? Update and bounty reason Due to the recent Great Flag Overhaul, mods no longer see close flags in the flag queue. Which means that the only way to get to them is via the review queue 1 Shog's solution is ideal in this case; let mods view the close queue as a list. (In fact, a list similar to the old flag queue -- which shows a list of mods who have seen the post and what mod actions have already been taken -- would be great) On Physics, the majority of the flags that we get are VTC flags. And the community isn't always able to close things on their own, so we have to step in. However, powering through the close queue isn't an option; because "skip"ing a post2 leads to it being dumped into the void (I can't get back to it unless I have a link). Extremely inconvenient. Could the workflow here be improved? 1. The /tools listing for posts with outstanding close votes doesn't work because it doesn't list posts which have been flagged but not VTCd 2. which I may want to take a closer look at later; gotta be careful with the binding votes.


I'm trying to remove an entity when isActive is false. When the entity attribute isActive is set to false, it enters if statement and removes the entity, when iterating through the entities list again after that and then crashes. From what I've researched I am using the correct way to remove an object from an array list.  the code when removing the entity and iterating through the list is      for (Entity entity : entities) {// itaarate through all the entities in list of entities          entity.render(shader, camera, this);// render each entity          if (!entity.isActive())// checks if entity attribute is active             entities.remove(entity);// removes entity from list      }   when using the debugger after it removes the entity from the list, it goes back to the top of the for loop and then displays this page    the Variables window when debugging     the full error that displays in the console is  Exception in thread "main" java.util.ConcurrentModificationException at java.util.ArrayList$Itr.checkForComodification(Unknown Source) at java.util.ArrayList$Itr.next(Unknown Source) at project.World.render(World.java:196) at project.Main.<init>(Main.java:152) at project.Main.main(Main.java:167)   the list being  created is  public static ArrayList<Entity> entities; // contains all entities

We all know you can't do the following because of ConcurrentModificationException:  for (Object i : l) {     if (condition(i)) {         l.remove(i);     } }   But this apparently works sometimes, but not always. Here's some specific code:  public static void main(String[] args) {     Collection<Integer> l = new ArrayList<>();      for (int i = 0; i < 10; ++i) {         l.add(4);         l.add(5);         l.add(6);     }      for (int i : l) {         if (i == 5) {             l.remove(i);         }     }      System.out.println(l); }   This, of course, results in:  Exception in thread "main" java.util.ConcurrentModificationException   Even though multiple threads aren't doing it. Anyway.  What's the best solution to this problem? How can I remove an item from the collection in a loop without throwing this exception?  I'm also using an arbitrary Collection here, not necessarily an ArrayList, so you can't rely on get.


I am trying to put 3 figures in this format:   but they appear like this:   I am using this code:  \begin{figure}[!htb]     \begin{subfigmatrix}{2}         \subfigure[Dados do vento e respectiva potência por modelo de turbina]{\includegraphics[width=0.4\linewidth]{Figures/tabvento.png}}         \subfigure[Perfil de vento típico da ilha da Brava]{\includegraphics[width=0.5\linewidth]{Figures/perfilvento.png}}         \subfigure[Curva de potência dos 2 modelos de aerogeradores]{\includegraphics[width=0.5\linewidth]{Figures/curvaaero.png}}     \end{subfigmatrix}     \caption[Dados gerais do recurso eólico utilizado para as simulações]{Dados gerais do recurso eólico utilizado para as simulações}     \label{fig:irrfdad} \end{figure}   Any suggestion how to solve it?

Is it possible to achieve the following layout with the subfigure package (and any other package/command I don't know about):  ############# ############## #           # #            # #  pic1     # #            # #           # #      pic2  # #           # #            # ############# #            #               #            # ############# #            # #           # #            # #   pic3    # #            # #           # #            # #           # #            # ############# ##############    Each picture should have a subcaption.


I've a table with 100+ (nullable) columns and 10,000+ rows. I'd like to fetch rows that have no columns null. id|f001|f002|f003|....f100 1 |null|aa  | ss |sada 2 |sdad|aa  | ss |sada 3 |as  |aa  | ss |sada 4 |null|null| ss |sada  In above case, only rows with ID 2 and 3 should be the output. I cannot use cursor nor can I specify the column names individually. PK is of course ID. It is legacy code and almost the entire application depends on it - can't do anything about the table design. Microsoft SQL Server 2016 (SP1) (KB3182545) - 13.0.4001.0 (X64) Oct 28 2016 18:17:30   Copyright (c) Microsoft Corporation Developer Edition (64-bit) on Windows Server 2016 Datacenter 6.3 <X64>  (Build 14393: ) (Hypervisor)

I'm trying to figure out an easy query I can do to test if a large table has a list of entries that has at least ONE blank (NULL / empty) value in ANY column.  I need something like  SELECT * FROM table AS t WHERE ANY(t.* IS NULL)   I don't want to have to do  SELECT * FROM table AS t WHERE t.c1 = NULL OR t.c2 = NULL OR t.c3 = NULL   This would be a HUGE query.


I making a tuning for our production servers for a portal, we have 4 servers, 2 for web and 2 for app, and there is a firewall before and after web servers (so yes there is a firewall between app and web servers) the issue here started from dropping idle connections between app servers and web servers by firewall, tried with a lot of solutions and now seemed that issue moved from stuck broken connections that was in app because dropping from firewall, this issue was happens when I have low load to portal, and to solve it I need to restart all app servers, now I have issue with high load days instead, and urgent solution was simply a quick restart Apache web servers, how to solve this issue.  I made changes by helping of Jboss loadbalancing configuration generator :    And monitoring connections in both servers using netstat command and with google analytics Real Time overview, I got the following stats with ~ 40 visitors after 3 days of last restart:  Web side (2 servers but connections her "for each" not total):  ESTABLISHED ~700 - 750 TIME_WAIT: 100-200 (big jumbs for one second 150 another 200 another 170 and then 120 and so)   App Side (here I counted all connections, most of them ESTABLISHED and few CLOSE_WAIT 0 - 5 each time I check):   S1 (4 instances running) : 900-950 S2 (5 instances running) : 1000-1100   Servers details :    On web 2x servers: Apache 2.2.14 / mod_jk 1.2.37  on app 2x servers: Clustered Glassfish 2.1.1 with ajp13 (6 instances / each server) All servers Solaris SPARC 64 V-CPUs 32GB ram.   My configurations :  Mostly like the generator gave me (u can see link) :  httpd.conf:  KeepAlive On ServerLimit         12800 StartServers        5 MinSpareServers     5 MaxSpareServers     20 MaxClients          12800 MaxRequestsPerChild 5000  ExtendedStatus Off   worker.properties:  worker.maintain=30 worker.template.type=ajp13 worker.template.session_cookie=JSESSIONID worker.template.lbfactor=1 worker.template.ping_timeout=10000 worker.template.connection_pool_timeout=10 worker.template.socket_keepalive=True worker.template.socket_timeout=600 worker.template.connect_timeout=10000 worker.template.prepost_timeout=10000 worker.template.connection_ping_interval=20 worker.template.ping_mode=A worker.template.socket_connect_timeout=600000   From glassfish side time-outs 10 seconds from cluster configuration side, I have:  HTTP service property :    connectionTimeout= 10000   Request Processing:    Thread Count: 2133 Initial Thread Count : 20 Thread Increment : 10    Keep Alive (enabled):    Thread Count: 400 Max Connections 256 Time out : 10 seconds   Connection Pool:    Max Pending Count 4096 connections   So:   So Is my configurations is correct ? How to solve high number of established connections or its safe?, I don't want down time again for apache if got high load again.

This is a  about  Related:      I have a question regarding capacity planning. Can the Server Fault community please help with the following:   What kind of server do I need to handle some number of users? How many users can a server with some specifications handle? Will some server configuration be fast enough for my use case? I'm building a social networking site: what kind of hardware do I need? How much bandwidth do I need for some project? How much bandwidth will some number of users use in some application?


I'm writing a multi-page resume and I have a long bulleted list that breaks in between page one and two. Since I have a lot of details about my time at one company I want to have the company's name followed by "(cont.)" as a header on page 2 but leave page 1 alone. That is to say, I don't want anything resembling a header on any page except page 2, so the top margin of page 1 should be unaffected. How do I do this?

I have a long header on my document (WORD 2010) and I want to remove it from the two first pages. But I don't know how to do that.


Anyone know how to get photos/files from a galaxy 4 that has a broken / blacked out screen - Ive tried every method possible ive read online and im getting no-were and ready to scream ...I cant seem to unlock the screen to allow a computer to extract files - Ive pluged the phone into multiple computers it wont read the phone...ive tried the Kies Program...the Samsung recovery system - can I plug the phone into something and see the screen separate from the phone?

So, yesterday my phone took a serious tumble.  It is now essentially useless, as the screen either fails to turn on, or when it does, there is nothing useful to see (just lines of primary colors, mostly).  I believe (from the fact that it still chirps at me when emails come in, etc), that the phone is still functional, otherwise.  I would like to perform a full system dump, so that I can get off any files from the phone (a TMobile SGS2 (hercules) running slimrom 4.3 build 1).  The sdcard probably isn't important, as I can just pull it, but the phone's own internal storage I should like to get a copy of.  When I plug the phone into a usb port, it 'mounts' the usb via MTP, and I can see all the files.  Unfortunately, when I do a select all | copy | paste operation, the paste op dies before transferring all files.  I've tried a couple other ADB shell operations, in hope of flipping regular USB mounting on, but nothing has worked.  Any ideas how I can get a full dump of my poor phone's contents?  Edit  Currently running a adb pull /sdcard/ ... Its copying files presently, but its too early to tell if its going to get evertying I'm expecting.  Edit #2  looks like its going to work...its taking a rather long time, but it appears to be grabbing everything I was expecting it to.


What I can remember is there was some sort of grotesque man killing monster that evolved(mutated) in the toxic sludge of a sawmill pond or the polluted area adjacent to the pond. The mill was closed down because of high levels of (mercury?) something used in the sawmill. It was causing animal mutations and infant mortality. A man was sent to the area to identify the cause of these problems and has to battle an organism bent on his destruction.   I probably read this novel in the late 70's or early 80's.

Sometime in the 1970s (I think) I saw a really awful film set in a small town by a lake. The film opened with some people camping out in the woods. One of them was zipped up in a sleeping bag. Something (as yet unidentified) moved in between the sleeping camper and the camera, and we heard a "crunch." When the creature moved off, we saw that it had bitten the head off the camper, causing a fountain of blood to spout of of the neck. Far from being shocking or gory, it was so badly done as to be laughable.  The main story was that these huge and nasty mutated creatures were coming out of the lake and eating people. A local industrial company was under suspicion for poisoning the lake, but repeated water tests showed it to be clean.  In the end, someone had the idea of testing the water at the bottom of the lake, which revealed it to be heavily poisoned with mercury. As mercury is much heavier than water, it had sunk, so the previous tests (done from a small row boat) had missed it as they only sampled the water at the surface.  They got it all sorted out eventually, and the bad guys ended up in prison.  After the credits had rolled, and you thought it was all over, another monster reared up in front of the camera and roared. I think we were supposed to go "Oh no, it's not all over!" However, the few people stupid enough not to have left by now laughed at the ridiculous sight and left, shaking their heads wondering why they had bothered!  I have a morbid fascination to see it again. Anyone have any idea what it was called?


I've the following but it doesn't work:  <%= (5..30).sample %>

How do I generate a random number between 0 and n?


I try to write test then it use static class.   I have class Person:  public class Person {   private int id;   public Person(String name) {     id = Id.generate(name);   }   public int getId() {     return id;   } }   And class Id:  public class Id {   public static int generate(String name) {     if (name.equals("I")) {       return 42;     }     return 100;   } }   This is my test:  import org.easymock.EasyMock; import org.junit.runner.RunWith; import org.powermock.api.easymock.PowerMock;  import org.powermock.core.classloader.annotations.PrepareForTest; import org.powermock.modules.junit4.PowerMockRunner; import org.testng.Assert; import org.testng.annotations.Test;  @RunWith(PowerMockRunner.class) @PrepareForTest( { Id.class } ) public class MockStaticTest {    @Test   public void test() throws Exception {     PowerMock.mockStatic(Id.class);     EasyMock.expect(Id.generate(null)).andReturn(55);      PowerMock.replayAll();     Person person = new Person(null);     Assert.assertEquals(person.getId(), 55);     PowerMock.verifyAll();   } }   When I run test, it throws NPE:  java.lang.NullPointerException     at Id.generate(Id.java:3)     at MockStaticTest.test(MockStaticTest.java:17)     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ...   On line 17 it calls code of static method Id.generate. In my opinion, it is wrong behavior.

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?


How to create a view of hierarchical taxonomies and each taxonomy lists all its nodes?  Item1 --node1 --node2 Item1.1 --node3 Item1.2 --node4 Item2 Item2.1 --node5

I am using Drupal 7 and Views.  I'm trying to use the generic Taxonomy/Term view and get a grouping I don't want. I want this:   Taxonomy 1:   Node A Node B  Taxonomy 2:   Node B Node C    (Notice Node B is in both taxonomies.)  What I'm getting is the following one:   Taxonomy 1:   Node A  Taxonomy 2:   Node C  Taxonomy 1, Taxonomy 2   Node B    How do I get the first example to display,  where Node B just appears under the different Taxonomies and doesn't create a new heading with multiple taxonomies?


If you open a user profile from any post on meta sites (not MSE) via Android app, the title, site icon, about section and badges will be from the user's most popular site, but the list of the post from this meta site.  E.g. if you open my profile from any of  (e.g.  can be opened via app) you will see the following:        Here are title, rep and badges from the Stack Overflow in Russian, but list of the posts and about section are from the Meta Stack Overflow (in English).   App Version: 1.0.95 Device Manufacturer: LGE Device Model: LG-H860 OS Version: 7.0 (172342203b663)

Steps to reproduce:    Go to a per-site meta. Find any post. Touch the user that posted it. See something like this (click to enlarge):           As you can see, it says "Stack Overflow" as the site, and shows my SO rep and badges, but it shows my Meta.Code Golf posts.


I'm following  to install git on my laptop. When I do:  $ sudo apt-get install git-core  This is what my terinal shows:  Reading package lists... Done Building dependency tree         Reading state information... Done The following packages were automatically installed and are no longer required:      libasprintf0c2:i386   libcroco3:i386   libgettextpo0:i386   libgomp1:i386   libunistring0:i386 Use 'apt-get autoremove' to remove them. The following extra packages will be installed:   git git-man liberror-perl Suggested packages:   git-daemon-run   git-daemon-sysvinit   git-doc git-el   git-arch git-cvs   git-svn   git-email   git-gui   gitk gitweb The following NEW packages will be installed:   git git-core git-man liberror-perl   0 upgraded, 4 newly installed, 0 to remove and 0 not upgraded.  Need to get 6,825 kB of archives. After this operation, 15.3 MB of additional disk space will be used. Do you want to continue [Y/n]? y  WARNING: The following packages cannot be authenticated!    liberror-perl git-man git git-core Install these packages without verification [y/N]?       E: Some packages could not be authenticated lucas@lucas-Inspiron-N5050:~$ sudo apt-get install git-core Reading package lists... Done Building dependency tree Reading state information... Done The following packages were automatically installed and are no longer required:   libasprintf0c2:i386   libcroco3:i386   libgettextpo0:i386   libgomp1:i386   libunistring0:i386 Use 'apt-get autoremove' to remove them. The following extra packages will be installed:   git git-man liberror-perl Suggested packages:   git-daemon-run git-daemon-sysvinit   git-doc git-el git-arch git-cvs git-svn   git-email git-gui gitk gitweb The following NEW packages will be installed:   git git-core   git-man liberror-perl  0 upgraded, 4 newly installed, 0 to remove and 0 not upgraded.  Need to get 6,825 kB of archives. After this operation, 15.3 MB of additional disk space will be used. Do you want to continue [Y/n]? y WARNING: The following packages cannot be authenticated!   liberror-perl git-man git git-core Install these packages without verification [y/N]? y Err httpq://py.archive.ubuntu.com/ubuntu/quantal/main liberror-perl all 0.17-1    Something wicked happened resolving 'py.archive.ubuntu.com:http' (-5 - No address associated with hostname) Err httpq://py.archive.ubuntu.com/ubuntu/ quantal/main git-man all 1:1.7.10.4-1ubuntu1    Something wicked happened resolving 'py.archive.ubuntu.com:http' (-5 - No address associated with hostname) Err httpq://py.archive.ubuntu.com/ubuntu/ quantal/main git amd64 1:1.7.10.4-1ubuntu1    Something wicked happened resolving 'py.archive.ubuntu.com:http' (-5 - No address associated with hostname) Err httpq://py.archive.ubuntu.com/ubuntu/ quantal/main git-core all 1:1.7.10.4-1ubuntu1    Something wicked happened resolving 'py.archive.ubuntu.com:http' (-5 - No address associated with hostname)  Failed to fetch httpq://py.archive.ubuntu.com/ubuntu/pool/main/libe/liberror-perl/liberrorperl_0.17-1_all.deb    Something wicked happened resolving 'py.archive.ubuntu.com:http' (-5 - No address associated with hostname)  Failed to fetch httpq://py.archive.ubuntu.com/ubuntu/pool/main/g/gi/git-man_1.7.10.4-1ubuntu1_all.deb    Something wicked happened resolving 'py.archive.ubuntu.com:http' (-5 - No address associated with hostname)  Failed to fetch httpq://py.archive.ubuntu.com/ubuntu/pool/main/g/git/git_1.7.10.4-1ubuntu1_amd64.deb    Something wicked happened resolving 'py.archive.ubuntu.com:http' (-5 - No address associated with hostname)  Failed to fetch http://py.archive.ubuntu.com/ubuntu/pool/main/g/git/git-core_1.7.10.4-1ubuntu1_all.deb   Something wicked happened resolving 'py.archive.ubuntu.com:http' (-5 - No address associated with hostname) E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?   How could I install git on Ubuntu 12.10? I can't even do it from the Ubuntu Software Center.  Thanks in advance!

I am getting this error frequently while updating Ubuntu 12.04 LTS. How can I fix it? Log is:  Ign http://archive.scrapy.org precise/main Translation-en Fetched 6,620 kB in 1min 21s (81.2 kB/s) W: Failed to fetch http://archive.scrapy.org/ubuntu/dists/precise/Release.gpg Something wicked happened resolving 'archive.scrapy.org:http' (-5 - No address associated with hostname)


When dealing with a problematic user, it is beneficial to be able to see if they have behaved badly in general.  Especially in the case of spammers, one of the greatest indicators that a post is promotional is if they are making similar posts across multiple sites, however, if other sites have removed the SPAM posts prior to reviewing their post, there is currently no easy way to tell if they are simply a new user who happens to have genuinely felt that a product was helpful to the question or if they are posting a self promoting link.  If diamond moderators were given the ability to see deleted posts on other sites, at least by users who have an account on a site they moderate, it would allow much better understanding of the intent of a user and aid determining if they are a problem user or not.

Possible Duplicate:             Having had a (hopefully) minor problem on Physics.SE, I asked for some advice and help from other moderators in the chatroom.   Alas, the user had deleted , so the moderators from other sites couldn't help, only Physics.SE mods and Stack Exchange team members were able to see the deleted post.  Is this use case a sufficiently compelling reason to grant community moderators the power to see deleted content on sites where they are not moderators and do not have 10k?


I run in my ubuntu the command dd if=/dev/zero of=/dev/null | dd if=/dev/zero of=/dev/null | dd if=/dev/zero of=/dev/null yes it did create 3 dd process but when i run jobs it only create 1 process. Please help to find the single command that will run dd if=/dev/zero of=/dev/null both in "tops" and "jobs" as background.

I've encountered a headache problem.  I want to execute mulitple commands in background, so I want to start them in bash one by one. It's easy to start one command in linux shell in background, just like this:  myCommand &   It's also easy to start multiple commands, just like this:  myCommand1 && myCommand2   or  myCommand1 ; myCommand2   But if I want to run multiple commands in background, I tried the following command format, but failed:  myCommand1 & && myCommand2 &   or   myCommand1 & ; myCommand2 &   Both formats fail. How can I run multiple commands which have & in one command line?


volition@sjb:~/gd/openslide-3.4.1$ sudo apt-get update Hit:1 http://archive.ubuntukylin.com:10006/ubuntukylin xenial InRelease Ign:2 http://dl.google.com/linux/chrome/deb stable InRelease                           Hit:3 http://dl.google.com/linux/chrome/deb stable Release                             Hit:5 http://cn.archive.ubuntu.com/ubuntu bionic InRelease                             Ign:6 http://ppa.launchpad.net/hzwhuang/ss-qt5/ubuntu bionic InRelease                 Hit:7 http://cn.archive.ubuntu.com/ubuntu bionic-updates InRelease   Hit:8 http://security.ubuntu.com/ubuntu bionic-security InRelease Hit:9 http://cn.archive.ubuntu.com/ubuntu bionic-backports InRelease                   Err:10 http://ppa.launchpad.net/hzwhuang/ss-qt5/ubuntu bionic Release            404  Not Found [IP: 91.189.95.83 80] Reading package lists... Done E: The repository 'http://ppa.launchpad.net/hzwhuang/ss-qt5/ubuntu bionic Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details.

When updating, I get the following error message:   W: The repository 'http://ppa.launchpad.net/mc3man/trusty-media/ubuntu xenial Release' does not have a Release file.   Here, I find another statement on this error:   This recommends removing certain PPAs; and, I'm not sure if I should do that since it might mean not getting the updates that I need.    Is this what I should do?


I am trying to learn more about macro programming - if that's the right word - in TeX and LaTeX.  I began by defining a quantity I called Sum : \newcount\Sum.  I then wrote \Sum=0.  Then I did some arithmetical operations on Sum, by using \multiply . . . by . . .  and \advance . . . by . . ..   Finally I wanted to print out (in the document) the value of Sum. For that I used the line    The Sum equals **\number**\Sum ,    and it worked as expected !  But later on, I discovered that I might just as well have written   The Sum equals **\the**\Sum ".    And now I wonder which of the two is the preferred way to write out a numerical value.  Are they equivalent ?  Or are they intended for different purposes - even if the results overlap in my example ?   Here is an MWE:  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %% %% Here is the example tex-file that illustrates use of \number and \the .    %%                                            %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%         \documentclass{article} \usepackage[paperwidth=4in, paperheight=0.8in]{geometry}  \begin{document}  \newcount\a  \newcount\b  \newcount\Sum  \a=1   \b=5  \Sum=0 \advance\Sum by \a  \multiply\Sum by \b \advance\Sum by \a  \multiply\Sum by \b  \noindent The Sum equals \number\Sum  \quad;\quad I used ``number''. \par \vskip 10pt \noindent The Sum equals \the\Sum     \quad;\quad I used ``the''.  \end{document}


When I try to export a map from the Layout Manager in QGIS, all the elements apart from the text annotation come through fine. These come through as tiny objects, with tiny font.  I could put labels on in the layout manager, rather than on the project window, but as far as I can see, there is no option for using the handy call-out boxes that are available in the main project window.

I made a map with annotations in QGIS 3.0.  This is how it looks like in the layout view:    If I print the map as PDF, one would expect to get the PDF to be WYSIWYG, right? However, it looks like this (it's about half the size):    Is there a way to influence the the scaling of the Annoations? I already tried to play with the Scale and Magnifier in the map view. I also tried to change the Scale in the map item.   The strange thing is, I believe it worked a few days ago. But today I installed QGIS 3.0 on a new PC and it showed the same behaviour...


In my paper, I tried to create an appendix and refer to it from the main text.  I tried to post it a very easy example. It does not depend on the journal class thus I don't know what's wrong with this simple syntax.    \documentclass[a4paper,10pt,draft]{article} \usepackage{pslatex,graphicx}  %opening \title{bla bla} \author{a, b, c} % \begin{document} % \maketitle % \begin{abstract} ipse dixit  \end{abstract} % \section{ introduction} % In Figs.~\ref{figA1}, \ref{figB1}, \ref{figC1} % Should be: In Figs. 1, 2, 3 \section*{Appendix} % \appendix % \begin{figure*}  \centerline{\includegraphics[width=0.2\textwidth]{figureB1.png}}  \label{figA1} \caption{Ipse dixit...}  \end{figure*}  \begin{figure*}  \centerline{\includegraphics[width=0.2\textwidth]{figureA1.png}}  \label{figB1} \caption{See Fig.~\ref{figA1}.} %Should be "See Fig. 1"  \end{figure*}  \begin{figure*}  \centerline{\includegraphics[width=0.2\textwidth]{figureC4.png}}  \label{figC1} \caption{See Fig.~\ref{figB1}.}  %Should be "See Fig. 2" \end{figure*}  \end{document}   I add two explicative images here:     shows the numbering in the main part of the text. Which should be "1, 2, 3" not "1, 1, 1" and the      shows the reference calling in the  appendix itself which, again, is wrong.  Many thanks in advice for your help.

\documentclass{article} \usepackage{algorithm}  \begin{document} \setcounter{section}{54} \section{A section with no label} \begin{algorithm} \label{myalg} \caption{An algorithm with the label `myalg'.} \end{algorithm} Reference to myalg: \ref{myalg}. \end{document}   With this code, the reference givens 55 (the section number); if I move the label after the caption command, I get the correct reference (1).  Why should this be the case? I find it confusing: when thinking about an algorithm as an environment, you expect to be able to label it right after you began it. At the very least I would expect some kind of error or "??" to appear, rather than the previous environment or reference-able entity being used.


I have two EditTexts:  <EditText     android:id="@+id/edit_text_1"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:text="0.35" />  <EditText     android:id="@+id/edit_text_2"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:text="0.3" />   and I parseDouble these EditTexts:  EditText e1 = (EditText) findViewById(R.id.edit_text_1); EditText e2 = (EditText) findViewById(R.id.edit_text_2);  double a1 = Double.parseDouble(e1.getText().toString()) double a2 = Double.parseDouble(e2.getText().toString()); Log.e("a1", a1 + ""); Log.e("a2", a2 + ""); Log.e("Result", (a1 - a2) + "");   0.35 - 0.3 = 0.05 but the result is:  12-06 13:14:00.816 11557-11557/com.example.android.test E/a1: 0.35 12-06 13:14:00.816 11557-11557/com.example.android.test E/a2: 0.3 12-06 13:14:00.816 11557-11557/com.example.android.test E/Result: 0.04999999999999999   Why is this happening?

public class doublePrecision {     public static void main(String[] args) {          double total = 0;         total += 5.6;         total += 5.8;         System.out.println(total);     } }   The above code prints:  11.399999999999   How would I get this to just print (or be able to use it as) 11.4?


I bought a used iPhone 4.  The previous owner re-set the phone, but did not remove the device from their iCloud.  It is asking me for their iCloud information when I try to set-up the phone.  I don't have contact with the previous owner anymore.  Is there a way to remove the device from their iCloud so I can use a new one?

Apple showed this new feature in iOS 7 called Activation Lock, that if you enable "Find My iPhone" on a device that is lost or stolen, a person that finds/gets the iPhone will not be able to wipe it or reset it. I'm curious whether the lock is designed to prevent these avenues to defeat the lock:   Can they completely drain the battery and leave the phone in that state for a couple of months and then try it? Or, can they use any third-party software that can access iPhone from outside the iTunes and wipe it that way? Or, can they simply "jailbreak" it and forget about this Activation Lock?   By what methods can this lock be defeated or bypassed?


I know a girlfriend that departed the USA Januanry 5, 2020  from NYC to Shenzhen. Trying to get her back to me in Long Island.  Are Chinese citizens permitted to re-enter the USA? She is a girlfriend and doing my best to help find an answer for her.  I know she can go to USA consulate in China  Shenzhen if there is one there.  I can also look that up.  Anyway,  quick and easy answer will be greatly appreciated.

This community wiki explains the current restrictions by the United States of America on the entry of individuals who may pose a risk of transmission of the SARS-Cov2, the virus which causes the Covid-19 disease.


I have read the tutorial on this and a fair amount of post and I am having trouble python3 regex matching in multi line mode. Consider the simple test:  text = "abcdef\nghijkl" exp1 = "^.*(def)" exp2 = "^.*(jkl)" print(text) import re re.compile(exp1, re.MULTILINE).match(text) is not None re.compile(exp2, re.MULTILINE).match(text) is not None   This results in:  abcdef ghijkl True False   This is the most basic example I could find, and all the other online regex matching ones of tried show that both should match with multi line but this doesn't. What am I missing? Any help is appreciated. Thank you.

For example, this regex  (.*)<FooBar>   will match:  abcde<FooBar>   But how do I get it to match across multiple lines?  abcde fghij<FooBar>


1.Let u and v be two positive integers with u/3<v<u/2.Then u mod v = u−2v. 2.Let u and v be two positive integers with u>v and let gcd(u,v) represent the greatest common divisor of u and v. If  u and v are both odd, then gcd(u,v)=gcd(u−v,v) How do I solve these questions? Can you share the steps to these quiz problems? Asked my prof and he says:In general, exercising in some rudimentary basic number theory, e.g. to see how modp behaves, helps. The simplest way is of course just to use the definition of remainder and quotient: For any two positive integers u and v there exist unique non-negative integers q and r such that u=qv+r and 0≤r<v. Just manipulating these q and r alone one can accomplish a lot (personal experience).

Let $a$, $b$, and $n$ be integers with $0 \le a \lt n$ and $0 \le b \lt n$. Suppose $a \equiv b \pmod n$. Then $a-b=0$ and $a=b$. Why does the congruence of two non negative integers imply that they must be equal?


While trying to export a query result set from PGAdmin4 on PostgreSQL12 to a CSV I am encountering the following error: ERROR:  could not open file "/home/linuxusername/Downloads/data.csv" for reading: Permission denied HINT:  COPY FROM instructs the PostgreSQL server process to read a file. You may want a client-side facility such as psql's \copy. SQL state: 42501  I'm somewhat new to PGAdmin but am familiar with Linux and SQL. Is there a configuration setting that I'm unaware of to allow PGAdmin to read and write to files and directories of Linux users? Using the /tmp works fine, but it's a pain to have to keep moving files to and from other directories and it's seriously cramping my work flow and slowing me down. Any help is much appreciated.

I have asked this question on SO but perhaps that was the wrong location. Apologies for double posting but the question may have a better audience here.  The original question is:   And the text is below. Thanks.    When running the postgresql [9.3] "COPY TO" functionality, the postgres user creates a file. I have told it to put the file in the tmp directory (although this can be changed if needed).  This is run as part of a cron job, the user is an "export" user set up especially for this task. The end goal is for the exported file to end up in /home/export/created_file.csv.  1) postgres can't stash the exported file straight into the home directory of another user without setting up the folder to be overly permissive.  2) the export user can copy the file from /tmp to it's home directory, but then can not clean up (delete) the postgres owned file in /tmp.  This is a daily process and so old files will need to be deleted in some way. I can add a cron job to clean up the files afterwards but I was hoping for a cleaner solution - either a way to change the permissions on the file that postgres creates, or some way to give the export user the additional permission of being able to delete that file in advance of it's creation.  Giving the export user the same permissions as postgres in general however isn't an option, as it would then have free reign over the database.  Any advice, be it unix based or postgres based would be very welcome, thanks.


I was trying to prove that $$\gcd(2a+1,9a+4) = 1 , a\in Z$$ My proof went like this: $$ (9a+4) = 4(2a+1) + a$$ $$ (2a+1) = 2(a) + 1 $$ $$ \Rightarrow \gcd(9a+4,2a+1) = \gcd(2a+1,a)=\gcd(a,1) = 1$$ The last line of reasoning seems intuitive for me; The greatest common divisor of any integer with 1 is definitely one because the only divisor of 1 is itself. However, the question of how to prove it formally arose. Thanks for any suggestions!

I am having trouble completing the proof if $a \mid b$ then $\gcd(a,b) = |a|$. My attempt: If $a\mid b$ there is a $k \in \mathbb{Z}$ such that $b = ak$. Let $d = \gcd(a,b)$. Then $d \mid a$ and $d\mid b$ so by hypothesis we have $d\mid a$ and $d\mid ak$. Hence, $d \leq \gcd(a,ak)$. We can easily see that the largest common denominator of $a$ and $ak$ is $|a|$, thus $d \leq\gcd(a,ak) = |a|$ so $\gcd(a,b) \leq |a|$. I am stuck and not sure how to show the reverse inequality $|a| \leq \gcd(a,b)$ to complete the proof.


I'm trying to install (from DVD) Ubuntu 14.04 LTS on my desktop computer along side Windows 8.1.  I am never given the option to do so.  I never get this screen:

Whenever I startup from the LinuxLive USB, and try to install Ubuntu 12.04, it only gives me two options instead of the usual 3 or 4. My options are "Replace Windows 7 with Ubuntu" and "Something Else". Whenever I go into "Something else", it looks extremely confusing. How do I install it side-by-side while using the "Something else" section? These are my partitions.   /dev/sda /dev/sda1 ntfs (104Mb, System Required Partition) /dev/sda2 ntfs (1000097Mb, Windows 7 Partition)   Or should I try reinstalling my installer on a CD rather than USB and maybe then it will have the "Install alongside" function?


I have a many to many association such as   class User < ActiveRecord::Base   has_many :working_groups   has_many :groups, :through => :working_groups  class Group < ActiveRecord::Base   has_many :working_groups   has_many :users, :through => :working_groups  class WorkingGroup < ActiveRecord::Base     belongs_to :user     belongs_to :group   And the Working_Groups association has some additional info about each relationship (such as order and type of membership):  create_table "working_groups", :force => true do |t|     t.integer  "group_id"     t.integer  "user_id"     t.integer  "position"     t.string   "role"     t.datetime "created_at", :null => false     t.datetime "updated_at", :null => false   In the user view, I'm trying to display a list of all the groups the user belong toand their type of membership (which is stored in the join table). The only way I found to get this done is something like this, that looks extremely ugly and not the most efficient thing ever...                Name         Role                                                                                Is there a better way to do this? There must be a better way...

New to both Ruby and Rails but I'm book educated by now (which apparently means nothing, haha).  I've got two models, Event and User joined through a table EventUser  class User < ActiveRecord::Base   has_many :event_users   has_many :events, :through => :event_users end  class EventUser < ActiveRecord::Base   belongs_to :event   belongs_to :user    #For clarity's sake, EventUser also has a boolean column "active", among others end  class Event < ActiveRecord::Base   has_many :event_users   has_many :users, :through => :event_users end   This project is a calendar, in which I have to keep track of people signing up and scratching their name out for a given event. I figure the many to many is a good approach, but I can't do something like this:  u = User.find :first active_events = u.events.find_by_active(true)   Because events don't actually HAVE that extra data, the EventUser model does.  And while I could do:  u = User.find :first active_events = [] u.event_users.find_by_active(true).do |eu|   active_events << eu.event end   This seems to be contrary to "the rails way".  Can anyone enlighten me, this has been bugging me for a long time tonight (this morning)?


Can i instal ubuntu on my Samsung Galaxy S Advance? If yes, what are the procedures?

With the announcement of the Ubuntu Phone OS I'd like to know what phone (and tablet) models are supported at this time.  Note from foss & Oli: We are making this the master question for all future "Will this work on <insert random tablet/phone/device here>?!" questions


Below I have an example image of a list with two separate icons. I am curious which one conveys the best action of removal from the list, either a trash icon or a closing x.  Specifically, this is being used to remove an entry from a list that the user has added.  Is there a better way to display this?  Note: I do not care about the UX interactions etc, purely the icon representation!

In the application I'm working on, we have two forms of getting rid of an item.   Delete: Permanently deleting an item from the system. Once removed, the data is gone. Remove: Removing a linked item from a group within the system. Data is not deleted and item can be added back into a group   Got 2 related questions   Is "Delete" and "Remove" as describe above common verbiage for these two actions? What icons should be associated to these actions?   Currently I've been using the Trash icon to represent Delete and "X" to represent Remove. I have comments from people in Dev saying Trash icon represent something that is recoverable when Delete isn't, would "X" be more representation for Delete.  I've also considered relabelling Remove as "Unlink/Unassociate", but those do not fit well since the user is putting items into a group instead of loosely associating them together. An un-link icon also has a more complex form and is less easy to recognize as compared to Trash and X.


I tried sudo apt-get upgrade and sudo apt-get update but any of them doesn't work. always  same error messages are showing 404 error.Not Found [IP: 2001:67c:1562::18 80]

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 have write the code of a table with more than hundred rows,  (in fact set of tables, with more than hundres rows at all !) and five columns.    Let's call the columns from left to right by A, B, C, D, E; I want to reverse the order of the columns, i.e. to get a table with columns E, D, C, B, A, respectively from left to right.       Is there any code or package to do this for me?   My code is something like the following:   \begin{table} \caption {computations of the first class} \begin{center} \scalebox{1} {  \begin{tabular}{| c || c | c | c | c |}  \hline A0 & C0 & B0 & D0 & E0 \\  \hline \hline  A1 & C1 & B1 & D1 & E1 \\  \hline A2 & C2 & B2 & D2 & E2 \\  \hline A3 & C3 & B3 & D3 & E3 \\  \hline A4 & C4 & B4 & D4 & E4 \\  \hline A5 & C5 & B5 & D5 & E5 \\  \hline A6 & C6 & B6 & D6 & E6 \\  \hline A7 & C7 & B7 & D7 & E7 \\  \hline A8 & C8 & B8 & D8 & E8 \\  \hline A9 & C9 & B9 & D9 & E9 \\  \hline \end{tabular} } \end{center} \end{table}       As @Alan Munn has been guided me to this , I have added one line to my code(befor \begin{tabular}):   \def\1#1&#2&#3&#4&#5\\{#5 &#4 &#3 &#2 &#1 \\}    But this does not changes any thing. Where is the problem?

I want to reverse (flip horizontal) all columns in some tables like this:  \documentclass{book} \begin{document} \begin{center} \begin{tabular}{c|c|c} $p$ & $q$ & $p\vee q$ \\ \hline $T$ & $T$ &T\\ $T$ & $F$ &T\\ $F$ & $T$ &T\\ $F$ & $F$ &F   \end{tabular} \end{center} \end{document}   I wrote these tables in Persian Xe-TeX and this language is a right to left writing language, and these tables appear reverse in output, so I used \lr command but the tables broke down and went out from centering also. I don't want to rewrite them. How can I fix it?


How to increase the size of overall appearance in Ubuntu 18.04. Consider the following screenshots with low appearance as shown below

I installed Ubuntu and the resolution of the desktop is so big that it only shows about 50% of the screen, but is shows up normal while using command line.   What should I type in the command line to change the desktop screen resolution?


I was trying to remove the last comma in the loop so it wouldn't show the extra comma on the last part. Already tried experimenting bunch of times on the code but it does not work at all.  System.out.println("--Unsorted Array--");   for(int i = 0; i < mergeS.length; i++){     System.out.print(mergeS[i]);     for(int j = 0; j < 1; j+=mergeS[i]-1){       System.out.print(", ");   } }   My expected output is 95, 85, 75, 65, 55 but the actual output is 95, 85, 75, 65, 55,

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]


Can any creature with the  (such as the third-party race ) qualify for character options which require the character to be an elf (such as the  feat), or are such options limited to full-blooded elves (and creatures with the Elf Blood racial trait)?

In Pathfinder, half-elves have the following racial trait:     Elf Blood: Half-elves count as both elves and humans for any effect related to race.   Since now I always considered that it meant that a half-elf could for example be an  which is "available to elven oracles", or a  which has "race: elf" as a prerequisite.  But it seems to me more and more odd that this is possible, on top of the other stuff that is specifically designed for half-elves.  What is the official ruling on the subject? Can a half-elf took an archetype, a prestige class, a feat or other stuff with "being an elf" as a prerequisite?  As a sidenote I deliberately didn't put "elf" as a tag since the same question could be asked for any race with the "X blood" racial trait (eg half-orcs).


Why is  so often performed on $z$'s that correspond to one-tailed $p$-values, when the mathematics allows for $z$'s that correspond to two-tailed $p$-values?

About combining multiple test statistics,  says     This Z-score (for the overall meta-analysis) is appropriate for   one-sided right-tailed p-values; minor modifications can be made if   two-sided or left-tailed p-values are being analyzed.   What are those minor modifications?


I need to use a feature that was recently introduced in the  package. Currently .  Since opening an account on  is impractical for an individual, I launch this question to the broad TEX.SE community.  Does anybody know of any online LaTeX editors that specifically provide the latest packages?

I have heard rumors that you can compile documents online, and more specifically that Google has a free online compiler, but I have never been able to find any. Is there a way to compile documents online, so that I can write and compile documents even if I don't have a TeX distribution installed on my computer?


I'm learning calculus, specifically derivatives and applications of MVT, and need help with the following exercice:      Show that, for all $n > 1$ $$\frac{1}{n + 1} < \log(1 + \frac1n) < \frac1n.$$    I tried to follow the below steps in order to prove the RHS inequality:   Proving that $f < g$ on $I$ from $a$ to $b$:  Step $1$. Prove that $f' < g'$ on $\operatorname{Int}(I)$.  Step $2$. Show that $f(a) \leq g(a)$ or that $f(a^+) \leq g(a^+)$  Following the above steps, let $f(x) = \log(1 + \frac1x)$ and $g(x) = \frac1x$, for all $x > 1$. One has  $$f'(x) =  -\frac{1}{x^2 + x} \quad \text{and} \quad g'(x) = -\frac{1}{x^2}.$$  We note that, for every $x > 1$, $f'(x) > g'(x)$. Moreover, $f(1^+) = \log(2) < 1 = g(1^+).$   My problem is that I got the wrong inequality sign in Step $1$.    Looking at the solution in my textbook, the author suggests using the MVT but I don't know how to apply it in this case.

Use the defintion of a logarithmic function to prove $$ \frac{1}{x+1} \le \ln(1+\frac{1}{x}) \le \frac{1}{x}$$ for any positive integer x.   ( Using defintion : $e^y=\ln^{-1}y$ )     Attempt:    Using the definition,  $e^y=\ln^{-1}y$ ,    I tried to prove the right hand side of the equality first by $ 1 +\frac{1}{x} \gt \frac{1}{x}$,     $\ln(1 +\frac{1}{x})\lt \frac{1}{x} \Rightarrow   e^{\ln(\frac{x+1}{x})} \le e^{\frac{1}{x}}$ but I am really stuck and lost on how I should do it so that one of the sides there is ln and the other side is the value and also for the equality to be $\le$ as $ 1 +\frac{1}{x} \gt \frac{1}{x}$  is strictly less than and is not equal.


Why does it only work if I invoke makeindex <filename>.nlo -s nomencl.ist -o <filename>.nls from the terminal/command window?

I have spent many many hours failing to implement nomencl for my PhD thesis. The problem seems to be with invoking makeindex and creating the .nls file  I keep reading that I must invoke makeindex or write a Unix command:  makeindex filename.nlo  -s nomencl.ist -o filename.nls   But I don't know how to do this. I would be grateful for some instructions i.e. where do I type the command?    I am using TeXShop 2.43.


This is the code:  \section{Introduction}  \subsection{Background of the Project} \setlength{\parindent}{10ex} An Information System (IS) is a collection of integrated modules that collect, manipulate, and...   This is the output:    The \parindent doesn't seem to be working. I need the paragraph to be indented.   I'd prefer a global solution, where all paragraphs are indented unless otherwise instructed.

I am trying to write a text where the first line of each paragraph has an indent(tab). But for some reason, in a chapter or a section or subsection, except the first paragraph, the rest of the paragraphs have an indent(tab). Is there any way to add an indent to the first paragraph in a chapter or section or subsection?


I have a scene in Blender in which I want to apply freestyle effects to just one object. Is this possible. How can I do it? (I'm using Cycles)

The question is how can I exclude an object from the freestyle render?  What I need to do is create a Clay render with the wire only on the airplane.  My scene is simple I only have two objects the "Toy Plane" and the "floor". For the Clay render I only override the materials to a simple clay material and done.    But this happens when I use freestyle. How can I tell freestyle to ignore the "Floor"?


Recently I have encountered an issue with steam. If you turn off your computer too fast, steam will register a game you were running as uninstalled. In my case it is GTA V. I have looked far and wide but only found that I should start installing and then steam will recognise the previous files. The problem is, I don't have enough space to start the download to be able to register it. I have slow internet and don't want to wait 5-7 hours to reinstall the game.

I've been playing a Elite Dangerous over the past few days. Now today, when I start up steam, it suddenly says it is uninstalled (name in sidebar is dimmed, and play button is replaced with install button). To check, I took a look at CCleaner's uninstall tab and it said Elite Dangerous was there: 24.9 GB of space.   I was thinking maybe just to install it again, maybe it will just install specific files that somehow got lost, but I don't have 24.9 gigabytes of space left on my computer, so it won't let me.  I'd rather not have to install it all over again, as it would take around 8 hours.  I have tried restarting my computer and steam.  What's happened?  EDIT: I am able to launch it from running EDLaunch.exe in the Elite Dangerous folder in steamapps/common, so it is purely a steam issue. But I'd like not have to do this everytime...


i'm trying to add about 50 points in certain areas in QGIS and they all have the same exact value,  so i figured i can just have the placed without entering the data and then select them and add the value through a formula  i just have on issue that i have to confirm using "enter" after placing each point .. so is there any way to add a point with just a click without going through the attribute dialogue and pressing "Enter"?

I need to create a lot of points with lots of attributes, but most of the fields are the same, so I don't want to edit all the fields all the time. Is there a "remember previous fields" function available?


Take three events $A,B,C$. Is it true that if $A\perp B$, $A\perp C$, and $B\perp C$, then $A\perp (B,C)$?   I don't see how to prove this. I stopped here: $$ p_{A|B,C}=\frac{p_{A,B,C}}{p_{B,C}}=\frac{p_{A,B,C}}{p_{B}p_{C}}=???=p_A $$

The example in question is from Rick Durrett's "Elementrary Probability for Applications", and the setup is something like this:     Let $A$ be the event "Alice and Betty have the same birthday", $B$ be the event "Betty and Carol have the same birthday", and $C$ be the event "Carol and Alice have the same birthday".   Durrett goes on to demonstrate that each pair is independent, since for example,   $P(A \cap B) = P(A)P(B)$.   However, he concludes that $A, B$, and $C$ are not independent, since   $P(A \cap B \cap C) = \frac{1}{365^2} \neq \frac{1}{365^3} = P(A)P(B)P(C)$.  I understand the reasoning here, and that one can generally show that arbitrary events $X$ and $Y$ are not independent by showing that $P(X\cap Y) \neq P(X)P(Y)$.   I am a little new to probability, though, and don't understand why exactly $P(A \cap B \cap C) = \frac{1}{365^2}$.   My progress so far:   I do see why $P(A) = P(B) =P(C) = \frac{1}{365}$, and thus why $P(A)P(B)P(C) = \frac{1}{365^3}$.  It seems like the sample space $\Omega = \{ (a, b, c) \mid a,b,c \in [365] \}$ -- i.e., all of the possible triples of numbers from 1 to 365, where 1 denotes January 1st, 2 denotes January 2nd, etc. From that, I can conclude $|\Omega| = 365^3$, but I'm not sure where to go from here.   It seems like once a single birthday is chosen, the rest are completely determined if they're all equal to each other - is this a good direction to go in?


I'm trying to install i3 desktop environment and I just can't figure out how. I'm following tutorial . and I'm stuck on the line:  echo "deb http://debian.sur5r.net/i3/ $(grep '^DISTRIB_CODENAME=' /etc/lsb-release | cut -f2 -d=) universe" >> /etc/apt/sources.list.d/sur5r-i3.list   My terminal says Permission denied

Sometimes I see sites offering Ubuntu packages via something like     Add this line  to your software sources: deb http:// something something   How can I add these to my package manager so I can install the software and keep it up to date? I'd like both GUI and command line options.


i was writing some code for 3d graphics and was making a simple window i get an error  Exception in thread "main" java.lang.NullPointerException at Display.main(Display.java:40) i read different articles about this type of exception but i cant resolve my problem even though i know what is this exception  i have added the comment in front of line 40 import javax.swing.*; import java.awt.*;  public class Display extends Canvas implements Runnable { public static final long serialVersionUID = 1L; private Thread thread; private JFrame frame; private static String title = "myframe"; private static final int width = 800; private static final int height = 600; private static boolean running = false;  public void Display (){     this.frame = new JFrame();     Dimension size = new Dimension(width , height);     this.setPreferredSize(size); } public synchronized void start(){     running = true;     this.thread = new Thread(this, "Display");     this.thread.start(); } public synchronized void stop(){     running = false;     try {         this.thread.join();     }     catch(InterruptedException e){         e.printStackTrace();     } } @Override public void run() {  }  public static void main(String[] args) {     Display display = new Display();     display.frame.setTitle(title);//this line has an exception     display.frame.add(display);     display.frame.pack();     display.frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);     display.frame.setLocationRelativeTo(null);     display.frame.setResizable(false);     display.frame.setVisible(true);     display.start();   }  }

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?


Context: Originally I had a dual boot machine, with Windows occupying around 180 GB and Ubuntu occupying 59 GB. However, I decided that I just wanted to use Ubuntu and I didn't need Linux, so I deleted the space for Windows (it's unallocated), and now I end up with the following situation:    However, when I try to resize Partition /dev/nvme0n1p5, it doesn't allow me to resize it futher. What specific steps should I take?

I am not able to expand my Ubuntu partition even though I have unalloacted space adjacent to it. Can someone help me please?


Is there any way to keep the two synchronised? So when a new event is added to facebook (regardless of attending or not), it comes up on google calendar?  I've tried pasting the webcal link from Facebook into google calendar, but this only gives me one event (the one furthest in the future).

I get a lot of invitations via Facebook, but I keep track of my schedule with Google calendar. Is there any way to automatically import or sync my Facebook events to my Google calendar?


Command was   sudo auto-apt run ./configure   Error message:  DISTRIB_DESCRIPTION="Ubuntu 16.04.1 LTS"     Location of "tcl.h": /usr/include/tcl8.6     Location of "tk.h": /usr/include/tcl8.6     Location of Tcl 8.6 library: not found     Location of Tk 8.6 library: not found     Location of X11 library: /usr/lib/x86_64-linux-gnu     Checking if your system already has zlib installed: yes.  Not all settings could be determined! See above for details.  The default Makefile was written. You will need to edit it before you can compile Scid.   I also can't find the libraries. How do I overcome this?

Simple enough question: is there some shell command (or GUI method) I can use that, given the path to a file on my system, tells me what package put it there? Assuming the file did in fact come from a package, that is.  Bonus question: what if it's a file that isn't installed on my system? Is there, say, a website that will let me look up a file and see what packages, if any, provide it?


dear all.i get some bad things.i try ask a questio at SO but my question is too obvious and then this closed.after that i try to ask a question again but it cant posted.why it happens?

If you are reading this, you may have been affected by one of our post quality bans. If so, it is important that you  to understand what has happened and how to regain the permissions that you lost. While trying to ask a question, one could see:  We are no longer accepting questions from this account. See  to learn more.  Likewise, for answers:  We are no longer accepting answers from this account. See  to learn more.   Why am I getting this message? Are deleted posts taken into account too? Is a question/answer ban the same as a suspension? How do I avoid getting a question ban? How long do I have to wait before I can post again? What can I do to release the ban? How can I reactivate my account? Can I simply create a new account? I'll just ask somewhere else on the SE network, and they'll migrate my question to the correct site! Will a ban on one Stack Exchange site affect my standing on other sites in the network? Does this apply to meta sites too? My account is in good standing. Why am I still blocked?


I have found a way to do something (safely remove of OAuth of .NET MVC4 application) on my own. I've searched a lot on the internet about this and can't find how to.  There's any place here that I can put the step by step on Stack Overflow?  -- EDIT --  Thanks for all replies and sorry for not seeing similar questions before asking. Later I'll put the step by step in Answer/Question format on the SO, I think this will help a lot of people.

I went looking for answers to a question I had, but didn't find what I was looking for.  Now that I've found the answer myself, I'd like to share what I've learned.  What's the best way to do this, if nobody else has asked the exact question I did?  Should I ask the question myself, and immediately post my own answer?  Or should I mark the question as a tutorial in the title?  ("Tutorial: How to ABC when using XYZ")


There is an "Informed" badge for reading the meta about page but it was awarded zero times and to make sure I tried reading the about page but did not receive it. If the badge is to be awarded here, then this should be 'fixed'. If not, it should be removed from the list of badges.

I've gathered from   that the Informed badge is not awarded here on the Big Meta.  But  does have this badge.  Why did this one user get the badge when the rest of us can't?


The two magnet pairs $N_2$ and $S_2$, $N_1$ and $S_1$ attract each other respectively which causes the wheel$_1$ to move in the clockwise direction and wheel$_2$ to move in the anti-clockwise direction. The rest of the magnets does not produce any effect because they are shielded by a magnetic screen. The continuous rotation of wheels can be used to run a turbine which can produce energy.so energy can be produced.

As a child, I imagined this device, which may seem to rotate indefinitely. I have two questions.   Is this perpetual motion machine already known? If it is, could you please give some references? What is the exact mechanism that makes it stop? By this, I mean an explanation, not simply "because it would break law of energy conservation". Of course energy conservation is true and this machine cannot work indefinitely. But for any known (presumed) perpetual mobile, there was an explanation, usually based on showing that the force generating the motion is . For example, Stevin obtained the laws of the inclined plane from the perpetual motion device     I would like to make some observations.   I don't try to convince anyone that it will move forever because I don't believe in breaking the energy conservation. It is true that , and nowadays some who think that there may be  in MWI believe, but I don't. But I don't consider an enough explanation simply to refer to the energy conservation. I am interested in an explanation showing exactly how the magnetic forces making it rotate, are balanced.  If the forces are balanced, only then friction will make it slow down and stop. I don't think that we can explain only by referring to friction, which in principle can be made as small as needed. There has to be a balance of forces. Why spending time trying to understand or explain something that admittedly can't work? Well, even though perpetual motion machines cannot actually work, I think they may be interesting as puzzles.


I want to find functions  $f: A \to B$ and $g: B \to A$ such that $g(f) = i_A$ but $f(g) \neq i_B$.   Is this possible? An exercise for one of my classes is to actually prove that if $g(f) = i_A$, then $f(g) = i_B$.   I've found functions where $f(g(x)) = x$ for most $x$, but failed for an exceptional choice of $x$. Would that be a counter example?   Are there examples where $g(f(x)) = x$ for all $x \in A$ and $f(g(x)) \neq x$ for all $x \in B$?

Two functions $f:A\rightarrow B$ and $g:B\rightarrow A$. Can someone give me an example where $g\circ f=id_A$ but $f\circ g\neq id_B$?


When running this Code:  import arcpy  from arcpy import env import os  #Specify the map document and the data frame mxd = arcpy.mapping.MapDocument(r"G:\\PythonCode\\mxd_test.mxd") env.workspace = r"G:\\LoopTest.gdb" #output file folder outPath = r"G:\Mxd_MapAutomation\\Test4\\"  FCs = arcpy.ListFeatureClasses()  # loop through all Featurecalsses in env.workspace for FCLASS in FCs:      #Skip all Text. OID and Geometry Fields - unfortunately WID, Shape Area etv is still included     AllFields = [f.name for f in arcpy.ListFields(FCLASS)]     LeaveOutField = [f.name for f in arcpy.ListFields(FCLASS,field_type='String')]     LeaveOutField.extend([f.name for f in arcpy.ListFields(FCLASS,field_type='Geometry')])     LeaveOutField.extend([f.name for f in arcpy.ListFields(FCLASS,field_type='OID')])     attrlist = [x for x in AllFields if x not in LeaveOutField]      # layer which has to change the attribute field     flayer = arcpy.mapping.ListLayers(mxd, "*")     featurelayer = flayer[7]      # text element that has to change (e.g. title...)     title = arcpy.mapping.ListLayoutElements(mxd, "TEXT_ELEMENT", "map_title")[0]     for attr in attrlist:          # change value field         featurelayer.symbology.valueField = attr          # change tilte         title.text = attr          # update view         arcpy.RefreshActiveView()         arcpy.RefreshTOC()          # export as jpeg         outJPEG = os.path.join(outPath, FCLASS + "_" + attr + ".jpg")         arcpy.mapping.ExportToJPEG(mxd, outJPEG, "PAGE_LAYOUT", 200, 200, 300, False, "24-BIT_TRUE_COLOR", 90, False)  del mxd   I get following error:      Traceback (most recent call last):   File "G:/DDP_loop_Code.py", line 35, in <module>     featurelayer.symbology.valueField = attr   File "C:\Program Files (x86)\ArcGIS\Desktop10.1\arcpy\arcpy\arcobjects\_base.py", line 87, in _set     return setattr(self._arc_object, attr_name, cval(val)) ValueError: hhfishing   and I have no idea why.. the code basically runs through all FC in the GDB. It does it correctly with the first FeatureClass and stops with the error in the second Feature Class. Even if I would put in other Feature Classes the Error would appear in the same way. All the fields are either float or integer and the field where the error appears is not different to any other field where the code works on..

How would I change the following code (outJPEG section) if I'd like to have the original attribute table name (eg Adress) and the attribute field name (eg ZipCode) as file name? (Adress_ZipCode)  The code as I have it now would just name the output JPG after the field in the attribute table (ZipCode)  Maybe os.path.split is an option but I am not so familiar with python and cannot make it work..  # export as jpeg  outJPEG = os.path.join(outPath, attr + ".jpg")  #atrr and outPath are defined in another part of the code arcpy.mapping.ExportToJPEG(mxd, outJPEG, "PAGE_LAYOUT", 200, 200, 300, False, "24-BIT_TRUE_COLOR", 90, False)


Let $f:\mathbb{C}\to\mathbb{C}$ be a holomorphic function such there exists a $c\in\mathbb C$ with $|f(z)|\leq c\cdot |z|^n$ for all $z\in\mathbb C$. Show that there exists an $a\in\mathbb C$ with $f(z)=a\cdot z^n$.   Proof.  My general idea is to show that the taylor series only has one non-zero coefficient:  $\displaystyle |a_k|\leq\frac{k!}{2\pi}\oint_{|w|=r}\frac{|f(w)|}{|w|^{k+1}}dw\leq \frac{k!}{2\pi}\oint_{|w|=r}\frac{c\cdot|w|^n}{|w|^{k+1}}dw\leq \\\displaystyle\leq \frac{c\cdot k!}{2\pi}\oint_{|w|=r}|w|^{n-k-1}dw$  Now using the standard estimate since $\oint=2\pi r$:  $\displaystyle \leq c\cdot k!\cdot r^{n-k}\longrightarrow\begin{cases}0,\ k>n\\c\cdot n!,\ k=n\\ \infty,\ k<n\end{cases}$ as $r\to\infty$  In conlusion the taylor series for now looks like $f(z)=\sum_{k=0}^{n-1}a_k z^k+ a_n z^n$ with $|a_n|\leq n!\cdot c$. What do I do with the remaining summands?  Edit: I would say that for $k<n$ we have $|z|^k>|z|^n$ for $z\in D_1(0)$. So since the estimate has to hold for all $z\in \mathbb C$ we can't have that either.

Function $f(z)$ is an entire function such that $$|f(z)| \le |z^{n}|$$ for $z \in \mathbb{C}$ and some $n \in \mathbb{N}$.  Show that the singularities of the function $$\frac {f(z)}{z^{n}}$$ are removable. What can be implied about the function $f(z)$ if moreover $f(1) = i$? Draw a far-reaching conclusion.  My attempt: If the singularities of $\frac {f(z)}{z^{n}}$ are removable, it is entire (not sure, need help with the justification) and bounded, so constant from Liouville's theorem, the constant value of the funcion is $i$, hence $f(z)=iz^{n}$.   But what about the $n$ here, is it arbitrary? Could somebody help me prove the removability of the singularities and suggest if my attempt is going the right way?


Is there a word to describe something that is not our own?  For instance:  The thoughts I was having were not my own, they were _______.  A possibility I thought of is alien.

ie.:  The idea was "(blank)".  It didn't come from myself, it was divine inspiration, dumb luck, etc.  or maybe: My essence/spirit was outside my body.  It was "(blank)".


gpg: [don't know]: invalid packet (ctb=6d) I tried sudo apt-get upgrade after sudo apt-get update in my tty4 because my close and minimise button,etc are not showing for any window and I can't even use my keyboard. So when I tried to upgrade it the /usr/bin/dpkg error was thrown and i tried to configure it but it shows ubuntu-keyring error processing package. There's a lot of keyring_get_keyblock failed and invalid keyring, on trying sudo dpkg-reconfigure ubuntu-keyring it says ubuntu-keyring is broken or not fully installed. Please help! It started when an article asked me to purge python and then I deleted a few files that made my inkscape disappear and while trying to fix that I rebooted my system and voila I can't even see any close or minimise or any buttons my terminal isn't working and now I'm stuck with tty.

I am a new Ubuntu user running Ubuntu 13.04.  I've been trying to install and use a DeDRM tool, but I've been having problems doing so. I was following some directions that said I needed a version of Python 2.7, but not anything Python 3.0 or later (because 3.0 versions are missing some necessary libraries?). I tried to install Python 2.7.5.6, but it didn't work. I thought it was probably because I had the later version of Python, so I went through terminal and removed Python 3.3, so I could install the earlier version of Python.  Now that I've uninstalled Python 3.3, a lot of applications no longer work, including the terminal and the Ubuntu Software Center. I have no idea how to fix this problem now.


The new  is terrible. But there's a reasonable problem that has been identified: non-signed-in users don't get to say anything. For obvious reasons, we have avoided letting them change the publicly displayed score or cast votes which award rep. But instead of letting the vote numbers pass into the void, we could simply display the number of <15 rep votes cast to the author of the post. Or it could be a high-rep feature, like vote counts, which is fetched upon request. That solves the problem without putting too many confusing numbers in front of users who may not know what exactly is going on, and without introducing any new 'reaction'-like features which disrupt the user's flow.

Anonymous and unregistered users with < 15 reputation (the amount required to earn the upvote privilege) will now see       feedback   on every post in the area that a logged in user would see "add comment":    When the post area is moused over, the area expands to:     Was this post useful to you? [Yes] [No]     once clicked it will say     sending feedback...   and eventually     Thank you for your feedback.   The goal is to offer the 90% of our traffic that is anonymous users a way to provide more meaningful feedback on posts rather than passively incrementing a view counter.  This click data is currently being evaluated to see what we can do with it. Ideas welcome!


If x = 0.999... (a) -> 10x=9.999... -> 10x-x=(9.999...)-(0.999...)  -> 9x = 9 -> x = 9/9 = 1 (b)   x = 0.999 (a) = 1 (b) ?  So... what is the right explanation for this occur? I know that exists a tiny error somewhere... I think that the subtraction of the repeating decimal is incorrect, because the principle of infinity. That's it? Am I right?

I'm told by smart people that $$0.999999999\ldots=1$$ and I believe them, but is there a proof that explains why this is?


Is there an analytical solution for adding up this sequence of numbers?  $$ n + \frac{n}{2} + \frac{n}{4} + \frac{n}{8} + \ldots + 1 $$  For example, let $n=32$,   $$ 32 + \frac{32}{2} + \frac{32}{4} + \frac{32}{8}+ \ldots + 1 = 32 + 16 + 8 + 4 + \ldots + 1 $$  I believe, we can express the formula like this:  $$f(n) = \sum_{i=1}^{\log(n)} \frac{n}{2^i}$$  However, is there an analytical solution to this problem?

I have a summation series of the form: $n + n/2 + n/4 + n/8 + n/16 +\ldots  + 1$. Is there a formula for this series? Basically, the denominators are powers of 2.


Yesterday I upgraded from ubuntu 12.04 LTS to 14.04 using the update manager. Everything went smoothly. But when I restarted my laptop, it went till the login screen and as i entered my password, it prompted an error      Failed to start session   I read in some blogs and even tried to use sudo dpkg-reconfigure -a, but even that failed with some errors. I feel it does not connect to the Internet through my router when I use the recovery mode.  Can someone please help me. I have lot of data in there and don't want to install a fresh copy of ubuntu 14.04. I am using a Dell Studio 1555 laptop with ATI Mobility Radeon 4500 HD graphic card.  I ran the following command  $ sudo dpkg --configure -a  Output: dpkg: error: unable to access dpkg status area: Read-only file system

While upgrading to 14.04 using sudo do-release-upgrade my network connection was interrupted and several packages failed to upgrade.  Running do-release-upgrade again reported No new releases found but apt-get listed many packages "kept back", so it seemed the system was in an intermediate state. I ran apt-get dist-upgrade which installed those packages again, then apt-get autoremove after which apt seemed happy.  However, after restarting I cannot log in at the GUI prompt. After entering my password the error "Failed to start session" appears in red. I am still able to log in from the command prompt, but I don't know what to do to solve or debug the GUI log in failure.


I have a Git commit, which has a summary, and then some description. So when I see the commit message via git log --format=%B -n 1 <commit>, it looks like this:  Commit Summary Line * Commit Description Line 1 * Commit Description Line 2 * Commit Description Line 3  When I try to store this in a Bash variable, however, thus:  message=$(git log --format=%B -n 1 <commit>)  and then I try to echo $message, I get the folder names from my current directory mixed with each of the lines from the commit message. What's more, I am not even seeing all lines from the commit message, just some of them. So, $message looks something like this:  Commit Summary Line folder1 folder2 folder3 Commit Description Line 1 folder1 folder2 folder3 Commit Description Line 3  Is there any explanation for this behavior? I just want $message to have all lines from the full commit message. I don't even care if they are in new lines or all in one line, I just want all lines stored in a string variable. How do I achieve this?

I've got a script 'myscript' that outputs the following:  abc def ghi   in another script, I call:  declare RESULT=$(./myscript)   and $RESULT gets the value  abc def ghi   Is there a way to store the result either with the newlines, or with '\n' character so I can output it with 'echo -e'?


I want to make a Feynman diagram using the Tikz-Feynman package, that is aligned horizontally. The command I use looks like:  \documentclass{book} \usepackage{tikz-feynman} \usepackage{tikz} \usetikzlibrary{shapes,arrows,positioning,automata,backgrounds,calc,er,patterns} \tikzfeynmanset{compat=1.0.0} \begin{document} \begin{center} \feynmandiagram[horizontal=a to b]{   i1 -- [fermion] a -- [fermion] i2,   a -- [photon] b,   f1 -- [fermion] b -- [fermion] f2, }; \end{center} \end{document}   According to the documentation, this should look like this:   but instead it looks like this:    How do I fix this?  PS: I am using a Sharelatex installation on my own server to compile the document.

Today I downloaded and installed the new  package to draw Feynman diagrams. I included the packages   \usepackage{tikz}  \usepackage{tikz-feynman} \tikzfeynmanset{compat=1.0.0} \usetikzlibrary{shapes,arrows,positioning,automata,backgrounds,calc,er,patterns}   into my preamble (changed them already many times).  However, already a simple sample code like  \begin{tikzpicture} \begin{feynman} \vertex (a) {\(\mu^{-}\)}; \vertex [right=of a] (b); \vertex [above right=of b] (f1) {\(\nu_{\mu}\)}; \vertex [below right=of b] (c); \vertex [above right=of c] (f2) {\(\overline \nu_{e}\)}; \vertex [below right=of c] (f3) {\(e^{-}\)}; \diagram* { (a) -- [fermion] (b) -- [fermion] (f1), (b) -- [boson, edge label'=\(W^{-}\)] (c), (c) -- [anti fermion] (f2), (c) -- [fermion] (f3), }; \end{feynman} \end{tikzpicture}   directly gives the error:     Package pgfkeys Error: I do not know the key '/graph drawing/node distance'.   Can you please help me? Thanks in advance!


I made some measurements near few cell towers and i have noticed that i get 2 values that is changing every few seconds. For example i get a reading of 20uW/cm2 for few seconds and after that the value spikes to 60uW/cm2 for some seconds and again it go down to 20uW/cm2 and so on. What is the reason for this phenomenon? Thanks.

I want to know how much power is radiated by cell towers of GSM (1.8 Ghz), 3G (2.1 Ghz), 4G (2.6 Ghz) ?   I want links to references if exist.


$$\operatorname {Var} (X)=\operatorname {E} \left[(X-\mu )^{2}\right]$$ Is the formula of variance. But if you think of it, you can assume that square was introduced just that something other than zero could be computed. But is there other mathematical explanation of raising in power? Can it be 3,4 etc instead of square?

So there is  about  why variance  is squared.   And the answer seems to be "because we get to do groovy maths when it is squared". Ok, that's cool, I can dig.  However, I'm sitting reading some financial maths stuff, and a lot of the equations on pricing and risk are based on variance. It doesn't seem to be the best basis for, you know, pricing exotic vehicles that are worth in the millions (or billions) that a formula for variance is used "because the maths is better".    To make a point  then, why not have the variance be from the cubed, abs cubed, or the 4th power (or even a negative power)?   eg (apologies, I don't know Latex)  Sum 1/N * |(x - mean)^3|   OR  Sum 1/N * (x - mean)^4   Would using variance-to-a-different power measurably alter pricings/valuations if the equations still used variance as usual (but the variance was calculated with the different power)?  Is there a reason why we stopped  at "power of 2", and are there any implications of using a variance concocted from a different (higher or lower) power?


My main breaker panel is feeding a panel in my basement. The main panel feed to the basement panel is 2 60amp breakers that have the thing across them so they trip together. My question is am I feeding 120amps to the basement panel or still only60 amps. My main breaker in the basement is a 100amp, how does that affect the double 60 amp feed to it?

On our circuit breaker, we have several circuits that are linked together by a metal handle. For instance, there are several cases of three 20A circuits all linked together, meaning you can only flip all three at once. Does that mean those three 20A circuits equal 60A? If not, what is the purpose of having multiple circuits linked together?


I want to show that for some proper subgroup $H\subsetneq G$ ($G$ finite) we always have $$G\neq\bigcup_{g\in G}gHg^{-1}$$ My attempt so far is letting $G$ act on the set $M$ of its subgroups of order $|H|$ by conjugation: $$\begin{matrix}G.M\end{matrix}\to M\\g.H\mapsto H^g$$  The stabilizer $G_H$ obviously then contains $H$, so $G.H$ is not empty and therefor we have that $|G.H|$ is a non trivial divisor of $|G|$. How do I continue from here?

Let G be a finite group and H be a proper subgroup. Prove that the union of the conjugates of H is not the whole of G.  Thanks for any help


Three Rings for the Elven-kings under the sky,      Seven for the Dwarf lords in their halls of stone,      Nine for Mortal Men doomed to die,      One for the Dark Lord on his dark throne      In the Land of Mordor where the Shadows lie.      One Ring to rule them all, One Ring to find them,      One Ring to bring them all and in the darkness bind them      In the Land of Mordor where the Shadows lie.   Everyone who has read the Lord of the Rings is familiar with the poem above. I am still making my way through the Silmarillion and will eventually get to reading the Unfinished Tales, which may hold the answer to my question: Is there any significance to the number of rings given to each race or is it just based on the number of kings/lords who ruled each race? Perhaps there is some information somewhere of why Tolkien chose these odd numbers or why the total number of rings is 20? Or perhaps there is no significance at all...

Is there any data in Tolkien (books/letters/etc..) to explain why there were precisely 9 Men rings and 7 Dwarf rings and 3 Elf rings? (the latter assumes that Sauron planned the number of Elvish rings to be 3 before he was thwarted by Elves making the rings themselves)  Was it because of the amount of tribes/kings he needed to deal with? Some magical/power limitations? Magical properties of numbers 9 and 7 (ala 7 Horcruxes)? A whim of Sauron's?    UPDATE: Looks like 3 and 7 are explained in the answers (3 elf lords and supposedly 7 Dwarf houses, though nobody provided canon proof).  What was NOT explained was why there were 9 Man rings?    If 9 was a meaningful amount, why? If it was merely "19-7-3" leftover, then why were there 19 total non-One rings made?


Can $\displaystyle\int_0^{\pi/2}x\cot x\,dx$ be found using elementary functions? If so how could I possibly do it? Is there any other way to calculate above definite integral?

$$\int_{0}^{\frac{\pi }{2}}x\cot(x)dx$$   I tried integration by parts and got $\dfrac{1}{2}\int_{0}^{\frac{\pi }{2}}x^{2} \csc^{2}x dx$ which doesn't help at all. I don't really know what to do. Any help will be greatly appreciated.