The question I have is: Why is space (almost perfectly) flat in our neighbourhood? (I am disregarding the deviations due to the sun and the planets.)  Is it correct to say that space is (almost) flat because throughout the universe, masses are distributed (almost) homogeneously? (Greetings to Sciama.)  Or is it more correct to say that space is (almost) flat because that is what occurs without any mass at all? In this case, the answer might be: space is almost flat because there is so little mass in the universe. Is this closer to the truth?  Or is there a third answer?

I know that in our particular case the inflaton field expanded the volume of the universe while simultaneously maintaining a mass-energy density close to the critical density all the while, thus the flatness.  But why that number? Why didn't the inflaton field maintain a density which would have caused some other kind of curvature instead? I thought inflation was supposed to solve the fine tuning problem but I still run into the problem.  Basically, what makes inflation "choose" which energy density to maintain? And if it always picks the critical density (for flat curvature), why is that?


I'm trying to do the Boethiah's Calling quest and I need a follower for it of course to sacrifice. But whenever I ask someone to be my follower they say I already have one. This is a problem because I don't have a follower. I had a dark brotherhood follower a month or two ago but I lost her and haven't been able to find her since. I've fast traveled and slept and tried multiple things to find her but to no avail. Now I can't get a new follower for the quest or get rid of my old one.

Whenever I try to get somebody to follow me in Skyrim they something in the lives with "You already have a follower.". The problem is, I don't.   I have not, to my recollection, had a follower at any given point in the game.  The only thing I can think of is that I have (spoiler)      finished Anriel's Endeavors and gotten him as a summon creature.    Or do I have a hidden follower that I can't remember. A dog or a horse perhaps? Note that I do not have a dog or horse following me now. I talked to dog once, and had a horse that died.  Is this a common/known issue? Is there a work around?  Any tips?


I need to download database structure with data. Total size of the DB is more than 3GB. If i use phpmyadmin it is not working. I have also tried by increasing the execution time in php.ini. I need some tool to import and Export the data base. My database server is Mysql server.  My requirement is any tool that will help to download Large database and Upload to another server. It should hold the download when internet fails. IF internet is ready it should continue the download process.  The answer already existing haven't worked for me. My issue is I need to export and import data from one server to other. if Internet Connection fails. It should not start a fresh export. It should continue the incomplete process.

I need to move 20 Gb MySQL database from on Debian server to another. The problem is that there is no way to create its backup since there are almost no free HDD space on the source server. What would you suggest?


I am a Filipino and have just been refused a UK Standard Visitor visa. My husband is British and currently working as a groundworker. It is so frustrating because the officer stated that my husband doesn't have the funds to support me. They even said that they're not convinced that my husband and I have a genuine relationship! That is totally absurd.  What should we do next?  We are planning to go to the embassy next month to complain about the result. Appended is a scan of the refusal letter.

Many of the UK visa refusals we see here share a common pattern and the prevailing reasons refer to V 4.2 (a) and (c).    I do understand that, while the applicants may describe very different individual circumstances, there's a consistent pattern and, broadly, fall into specific categories:    Credibility (lifestyle, lack of ties, visit history, lies & omissions) Funding (insufficient funds, provenance of funds, funds parking) Sponsorship (family, friends, employer)   Question: What most commonly triggers a UK visa refusal where V 4.2 (a) and (c) are given as the grounds?  Secondarily: Given that there is a clear pattern, to what extent are these refusals predictable? Does sponsorship make a difference? Is there a set of personal circumstances, however abstract, where a refusal is all but guaranteed? For example, why do those we see here on TSE who sought entry for the PLAB or British Army appear to be refused with a common theme? Is there a uniform shortcoming or is it just discrimination?   PLAB: What is about applications for a visa, for the purpose of sitting the Professional and Linguistic Assessments Board (PLAB) exam, that seem to invite refusals. After all, the test is given so that international medical graduates can show that they qualify to practise medicine in the UK. The first part, PLAB 1, can be taken in centres outside of the UK. However, PLAB 2 can be taken only in the UK. Why can't you can't get a visa just to sit the exam, promising that you'll leave immediately after?    British Army: Since Commonwealth citizens are eligible to apply online to join, even those who don't reside in the UK, why is it so difficult to get a visa just to attend an interview to see whether you are suitable? Even with an invitation from the Army, such visa applications seem to be unsuccessful. Isn't a career in the British Army a valid reason?     Lastly:  After such a refusal, what approaches would increase the chance of a successful application?


What is the correct punctuation when repeating a question as a statement? See the following example, and my best guess:  John: Sorry I missed your phone call. What's happening? Bob: I was wondering if you wanted to get some lunch.  My discomfort with Bob's response is the following: Bob's response very strongly alludes to an underlying question, but because it is technically a statement, it doesn't get punctuated with a question mark. Question: If I wanted to communicate this response but include a question mark (to more obviously visually communicate that there is a question that needs answering), how could this be done? My best idea is to simply restate the question in its entirety and join with a colon. For example (please correct me if any part of is incorrect):  I was wondering: "Do you want to get some lunch?"

This may be related to a general grammar rule, but which of these is correct?     I wonder if Steve Jobs will be giving the keynote speech at WWDC this year?   or     I wonder if Steve Jobs will be giving the keynote speech at WWDC this year.   My hunch tells me the question mark is incorrect, but I find myself instinctively wanting to add it. Is there a rule about this type of situation?


I was looking around a bit and stumbled on something I found really strange...  First thing that prompted my curiosity was seeing a certain user who obtained the badge "Enlightened" several times in a row within a short time span of 1 minute:    Looking around some other badges ("Nice Answer", "Good Answer", "Great Answer"), there seemed to be some more of the same thing. Well, no more about badges (you can see a bit of them on the activity page under badges), let's move on.  Onto the user's page, all the rep are in multiple of 3:    I mean, don't you just find it strange? Even the downvotes are in multiple of 3 and at exactly the same time. Could it be a bug or is it really that easy to stack up so many badges in a row. If so, I'd like to know the secret ;)  NOTE:   I hope it's okay if I don't blur the username. I don't want to bring the user negative attention, but it just jumped out to me. I'm not sure what to tag, so I'm using the discussion tag for now, since I'm not even sure what's happening here.

I just took a look at the Recent Badges column and the high frequency of occurrence of a username caught my attention:    I then visit the links of these badges to see how this user (jrharshath) earn all these badges at once. It turns out that these questions are quite old and he should have earned them a long time ago.  Famous Question:     Notable Question:     Good Question:     Why did he earn all these badges at the same time?


How do I, and is it even possible, get actual maximum size of character array passed to a function as a pointer?  int size=0; while (char_array[size++])   this won't work, as it will return number of characters in the array, and I need its actual size.  Also I cannot use any libraries (specifically string) or my own classes or basically anything useful.  EDIT as it turns out, I will have to explain the assignment quickly. And I am told not to do it in the comments. So here it is:  I have to implement a function that has three character arrays passed as pointers. Cannot change that in any way. First one is a string with commands included in that string (important). The commands are simple: delete x letters, and so on, but some are tricky, like add x letters from second/third character array to the right. Why tricky? Because those arrays may contain more commands, which will then be added to the string I'm working on. So one way to do it is to work on the string passed to a function, but that would be very slow, and I would have to add/delete characters in the middle, which basically means moving the rest of the letters many times. So I would have to have m*n opertions, where n is size of string and m is ammount of commands. But only n operations if I could write to another string. However I don't know how much space would I need, because the commands could add more commands, which would add more letters to initial ammount of characters. Checking the ammount and type of commands beforehand would be slow and make the whole thing rather pointless. However I know that the string passed to the function will have enough space (it's in the assignment specifications). So if I just could access it's size, I could declare another string with same size, knowing it would fit the resulf for sure.  So what will I do? I will declare this local string that I'm writing into with initial size and then if the result is greater I will rewrite it to a bigger string. Which will give me n times z operations, where z is a number of rewrites, which is still better than n times m, but worse than just n.

First off, here is some code:  int main()  {     int days[] = {1,2,3,4,5};     int *ptr = days;     printf("%u\n", sizeof(days));     printf("%u\n", sizeof(ptr));      return 0; }   Is there a way to find out the size of the array that ptr is pointing to (instead of just giving its size, which is four bytes on a 32-bit system)?


Background Many events are included in the revisions list, primarily:  edits deletions closures  However, the only thing that creates the link to the revisions list is edits. This link is in the form of "edited x minutes ago". This means an  assortments of events can occur to a question that has never been edited without any evidence of that fact. I tested this on a question of my own which I had never edited, but probably needed a minor edit. You can see the . I deleted it then undeleted it, all without any revision list link appearing, I finally edited it and the full revisions list was available How this affected me This affected me when I asked a question regarding an on going event. I was criticised for posting a duplicate of a question that was "still on the front page!". However what had actually happened (I eventually found out) was that the original was posted, self deleted and then undeleted a few minutes later (for whatever reason). I posted my duplicate while the original was deleted but there was no (available) record of that until the question was later edited. Request Have any event that are included in the revisions history also generate an appropriate link to the revisions list on the question

In the latest  I saw this:     2013-02-18: The revision history of a question that was closed as a duplicate is now showing the chosen originals as part of the "Closed as duplicate" notice.   That sounds cool, so I went to go see what it looks like and realized that questions with , but no edits, don't have an "edited <date>" link to click.  This applies to questions which had a bounty posted, or have been closed, reopened, locked, deleted, etc.  Examples:   , revisions:  , revisions:          I realize I can manually type the URL:  https://meta.stackoverflow.com/posts/168761/revisions   But it would be nice to simply click. It could say "revised" instead of "edited" if there were no edits:


trigger Splittrigger_newclass on Indexing__c (before delete,after insert) { list<C_Voyage__c> lstvoyage=new list<C_Voyage__c>();     list<string> q = new list<string>();     list<string> p = new list<string>();         //To store parent ids     list<id> IndIds=new list<id>();     for(Indexing__c Ind:trigger.old)     {         IndIds.add(Ind.id);         system.debug('inids>>>'+IndIds);     }       //Collecting all child records related to Parent records     list<C_Voyage__c> listVoyage=[select id,main_case_id__c from C_Voyage__c where Indexing__c in :IndIds];     system.debug('listVoyage'+listVoyage.size());     //deleting child records     delete listVoyage;      for(Indexing__c y:trigger.new)     {         system.debug('INdex>>>>>'+y);         if(y.Voyage_Created_Ref__c !=null)         {     p=y.Voyage_Created_Ref__c.split(',');     for (Integer i = 0; i < p.size();i++) {         C_Voyage__c tst = new C_Voyage__c();         tst.Voyage_Ref__c = p[i];         tst.Voyage_Type__c = 'Created';         tst.Indexing__c= y.Id;         tst.main_case_id__c= y.Case_Indexing_Ref__c;         lstvoyage.add(tst);         system.debug('listofvoyage>>>>>'+lstvoyage);     }    upsert lstvoyage;      if(y.Voyage_Amended_Ref__c !=null)     {      q=y.Voyage_Amended_Ref__c.split(',');      for (Integer j = 0; j < q.size();j++) {         C_Voyage__c atst = new C_Voyage__c();         atst.Voyage_Ref__c = q[j];         atst.Voyage_Type__c = 'Amended';         atst.Indexing__c= y.Id;         atst.main_case_id__c= y.Case_Indexing_Ref__c;         lstvoyage.add(atst);     }     upsert lstvoyage;     }     } } }

This is a canonical question and answer developed by the community to help address common questions. If you've been directed here, or your question has been closed as a duplicate, please look through the resources here and use them to shape more specific questions. To browse all canonical questions and answers, including more unit test resources, navigate to the  tag.  This canonical question is intended to address several classes of common questions by providing a quick summary and links to comprehensive resources:   How is code coverage obtained and calculated? How do I increase my coverage?  Why can't I cover these lines? Why isn't the body of my loop or conditional statement covered?


When you accept an answer, it seems you should also (by etiquette?) upvote the answer. Why doesn't the checkmark count as an automatic upvote?

Is there ever a case where you would want to accept an answer, but not upvote it?  I can't think of a single situation where this would be the case.. So would it not make sense to have the "Accept" button upvote the answer too?


Often we see in news they say AstraZeneca is 95% effective, while Chinese vaccine is 50%. I have question how to interpret these numbers.  Does this mean that if you get vaccinated with AstraZeneca for example, then assuming above numbers, there is 5% chance you will get the virus?  Also my question is do these percentages say anything about whether you will develop severe symptoms or not? For example does it mean that when we say Chinese vaccine is 50% effective does it mean it will reduce the severity of symptoms on half (due to 50%)?

Pfizer's paper () published recently states the following in the Efficacy subsection of the Results section:  Between the first dose and the second dose, 39 cases in the BNT162b2 group and 82 cases in the placebo group were observed, resulting in a vaccine efficacy of 52% (95% CI, 29.5 to 68.4) during this interval and indicating early protection by the vaccine, starting as soon as 12 days after the first dose.  Can anyone explain in simple terms the calculation of 52%? I am guessing that this number was obtained from:  But why is that the calculation? Does it depend on the fact that the vaccine and placebo groups were in equal numbers, such that by observing 82 COVID-19 cases in the placebo group, we match 82 subjects in the vaccine group, and since only 39 confirmed cases were observed in the vaccine group, the authors conclude that the "complementary (to 82)" 43 subjects did not become sick, and thus the vaccine is efficient in 52% of the subjects?


I heard several strategy about macbook power supply connection:   keeping alway at least 50% of battery level let unplugged until reaching the 10% warning perform once a month a full discharge   What is the best strategy to keep the battery performant on the long run? I suppose it involve some physical battery notion but also how OSX handle the battery management at the software level.

How do you maximize the cycle count of your battery?  There seems to be a debate between:   Leave plugged in 24/7 but do a full cycle once a month Charge to ~100%, drain to ~10%, repeat.   NOTE: Taking your   Which method is better and why? How much of a difference does it really make?  Here are some of the better sources I've found about battery behavior so far. Even still I feel they don't conclusively answer the question above. See my elaborations below:           Elaborating on Option 1  Now IF Apple engineers were smart and optimized for AC draw when plugged in to not use up your charge cycles, then it seem logical to assume that you are using effectively none of your 1000 charge cycles while plugged in. If that's the case, it would seem that the LiPo drop from holding at 100% would be vastly outweighed by the fact you're not using any charge cycles.  However, this is a purely speculative assumption and I could find no evidence to either confirm or deny.  If this is NOT true, and the AC adapter only goes to charging the battery, then there would be no difference. Your battery would drain to 99%, then back up to 100%, then back down to 99%, etc. Those micro-charge cycles would add up at the same rate as 100% -> 0% -> 100%, and you would get no gain. In this case the negative effect of holding LiPo batteries at 100% would outweigh everything else.  Elaborating on Option 2  There are lots of good reasons why Option 2 is the way it is:   Because of known LiPo chemistry issues, holding a 100% charge for a long time causes the battery to degrade Apple specifically recommends not to leave it plugged in all the time  Draining a battery all the way to zero all the time is bad for the cell (Which is why ~10% is used) Heat is a killer, and when plugged in AND charging, you get extra heat that causes damage.   There are a couple reasons why I'm challenging Option 2:   It seems silly that the most intuitive use case for thousands of people that use their macs as primary computers is wrong. If the hypothesis in option 1 is true, you're just burning unnecessarily through your finite charge cycles. It's a pain to have to remember to keep plugging in and plugging out and be worried about whether or not your device is plugged in.


The question is about ship stability calculations. We need to solve moment = force × distance, but in stability they put mass × distance. How, and why? Deadweight is the total weight of cargo, stores, etc. which a ship carries or can carry. -"this will produce a maximum dead weight of 72,350 tons". If it is in tonnes how can it be weight? It should be mass. If the cargo of 200 kg is loaded 2 meters from center line it will create momentum of ? Moment = 200 × 2 = 400 kg m, or 0,4 tm.  How can we put mass in equation for moment, is should be force, and force is in Newtons. Weight is force, mass is not. In water ship has weight or mass? Why do they use word weight in stability when the measure is in kg or tonnes. It should be mass?!  I know that in physics mass and weight are two different things. Mass is not a force, weight is force, but ship in water has force, but we express it in tonnes, not newtons. Is it because mass × gravity = volume × density × gravity so if we remove gravity we get mass = volume  × density, so if the ship, water it floats in and cargo that is going to be loaded are in the same gravity force field we can use amount of mass as weight?

Yeah, those circular metal disks. Weights or masses? I call them weights because when I attach them to a spring I'm interested in their weight, but it feels odd saying a "Pick up the 100g weight". "Pick up the weight with a mass of 100g sounds better" but it still feels wrong.   I don't like to call them masses, because I've never heard anyone else call them masses, unless it's someone trying to correct me for making the 'mistake'.


How to search a string in c# using Regex, ignoring accents;  For example in Notepad++, for ancient Greek, searching with regex : [[=α=]] will return: α, ἀ ἁ, ᾶ, ὰ, ά, ᾳ, ....   I know Notepad++ is using PCRE standard. How to do this in c# ? Is there an equivalence syntax ?  Edit:  I've already tried string normalization. Is not working for Greek. for example : "ᾶ".Normalize(NormalizationForm.FormC) will return ᾶ. It looks like normalization removes accents only in case of "Combining characters". The ᾶ character is a separate character in Unicode!

I'm trying to convert some strings that are in French Canadian and basically, I'd like to be able to take out the French accent marks in the letters while keeping the letter. (E.g. convert é to e, so crème brûlée would become creme brulee)  What is the best method for achieving this?


I encountered idea of considering Sample space $\Omega$  as collection of function so far as I saw.  Can you show the proof of thesis $x \neq \{x\}$? In a book I saw this thesis is included in context of Russell's paradox.  Best regards,

In Russell's famous paradox ("Does the set of all sets which do not contain themselves contain itself?") he obviously makes the assumption that a set can contain itself. I do not understand how this should be possible and therefore my answer to Russell's question would simply be "No, because a set cannot contain itself in the first place."  How can a set be exactly the same set as the one that contains it? To me it seems unavoidable that the containing set will always have one more additional level of depth compared to all the sets which it contains, just like those russian matryoshka-dolls where every doll contains at least one more doll than all the dolls inside it.  Of course one can define something like "the set of all sets with at least one element" which of course would include a lot of sets and therefore by definition should also include itself, but does it necessarily need to include itself just because its definition demands so? To me this only seems to prove that it's possible to define something that cannot exist beyond its pure definition.


According to the "list verse" time gets to a pause when someone or something travels at the speed of light. But a question still lies in my mind, if time always travels forward and does not stop at any point then how come it gets to a pause with respect to a body travelling at speed of light?

I read with interest about Einstein's Theory of Relativity and his proposition about the speed of light being the universal speed limit.    So, if I were to travel in a spacecraft at (practically) the speed of light, would I freeze and stop moving?  Would the universe around me freeze and stop moving?  Who would the time stop for?


It's always bugged me. My research behind this question was rather shallow, so I apologize if it's a duplicates. Thanks!  Edit, example: Say you don't know who you are talking to on Reddit, you simply know -their- username. Is it just the way in English to call people when you don't know who -they- are? Thanks again!

Is there a pronoun I can use as a gender-neutral pronoun when referring back to a singular noun phrase?  Each student should save his questions until the end. Each student should save her questions until the end.


So I have a String of text lets say "hello world () (foo bar) (foo bar 2 (this looks cozy)) (foo bar 3..." Is there a regex pattern I could use that will get the parentheses and include any parentheses inside them to nth depth. So the matches would be "()", "(foo bar)", "(foo bar 2 (this looks cozy))", ...?

I need a regular expression to select all the text between two outer brackets.  Example: some text(text here(possible text)text(possible text(more text)))end text  Result: (text here(possible text)text(possible text(more text)))


I'm reading a file line-by-line with Java and parsing the data in each line for a report. Periodically, there will be a URL that's been written to a line, and I want to bypass that line. I need to set up an if...then that tests for the presence of a URL -- in this specific case, I define that as the first four bytes of the line reading http. If the condition is true, read the next line in the file, but if the condition is false, send the current line to the parser for report output.   Simple, no? I'm running into issues where I cannot get my if..then statement to accurately recognize a true condition. My only clue is that when my inputString is equal to the test value, it passes as true. Beyond that...I can't spot anything out of the ordinary.   public class testClass {     public static void main(String args[])     {         String inputString1 = "http://www.google.com/r";         String inputString2 = "google";         String inputString3 = "google search";         String inputString4 = "http";         parseInput(inputString1);         parseInput(inputString2);         parseInput(inputString3);         parseInput(inputString4);     }     //     private static void parseInput(String inputString8) {         int httpFlag;         if (inputString8.substring(0,4) == "http")              { httpFlag = 1467; } else             { httpFlag = 10644; }         System.out.println(inputString8+" "+inputString8.toLowerCase().substring(0,4)+" "+httpFlag);       }  }   Here's my output:  http://www.google.com/r http 10644 google goog 10644 google search goog 10644 http http 1467   I am expecting 1467 for both inputString1 and inputString4.  The console appears to display my input and substring properly, and nothing in the Java Documentation suggests that my substring would be a char array or anything apart from a string, so I can't figure out why http as the first four bytes of a 4-byte string is "different" from the first four bytes of a (4+x)-byte string. What am I missing?

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


I am looking to take a portable AC unit and hopefully run a tube through a wall in another room while still cooling the room the unit is located. I have searched to attachments that could help but have come up empty. Any help would be appreciated.   DR

I have a Kenmore portable air conditioner model - 408.72012.  this particular model can be housed on the outside of the building and the A/C air is vented into the inside space (normally through a window).  Almost the opposite of what you normally do with a portable A/C unit.   I have an office right next to my LR and want to pump the A/C into my LR sometimes and other times into my office.  Because I did not have a window to have my A/C Air come into my office through a hole we cut and placed and  fit a flexible dryer vent pipe (the white floppy accordion style)through the wall and on the inside of my office I have the dryer vent cover with flaps (like you would normally see on the outside.  This prevents and critters from getting in.  I am trying to figure out how to split the out flowing A/C air though a "dual Y pipe of some type to flow into my office when I want it in there and my LR when I want it in there.   IS there any such  thing as a U pipe that is not rigid that I could use for this and also some how block them when I want it to flow in only one side or the other?


Does anyone know any simple way to retrieve the country from a given IP Address, preferably in ISO_3166-1 format?

I want to retrieve information like the city, state, and country of a visitor from their IP address, so that I can customize my web page according to their location. Is there a good and reliable way to do this in PHP? I am using JavaScript for client-side scripting, PHP for server-side scripting, and MySQL for the database.


Today i installed ISO on my USB through Rufus. At the end of unpacking progress it gave me a crash and now my USB is in read-only mode. I tried all ways on Windows and even something on live Ubuntu. Nothing helps.

When I plug in my USB flash drive, it shows up on my computer as write-protected or read-only. I am unable to transfer data to it, nor can I modify or delete any files already stored on it. I also cannot repartition or reformat the drive using Windows Disk Management, DiskPart, GParted, or other tools. The drive does not have a write-protect switch.  Why did this happen and what can I do about it? Is there a way to remove the write protection?  (Note that this can happen with some memory cards, too, as they often use controllers similar to those used in flash drives. In some cases, the system may report that the drive or card was formatted successfully even though it was never actually formatted; the original data reappears when the device is reinserted.)     This question comes up often and the answers are usually the same. This post is meant to provide a definitive, canonical answer for this problem. Feel free to edit the answer to add additional details.


What is the difference between following two implementaion,if no difference why we need Extension methods ? (public static List<TSource> ToList<TSource>(this IEnumerable<TSource> source);)  1.IEnumerable<Student> myExtension = mtyStudent; // "mtyStudent is colletion"     myExtension.ToList();  2.List<Student> myStudent= Enumerable.ToList(myExtension);

A "non-believer" of C# was asking me what the purpose to extension methods was. I explained that you could then add new methods to objects that were already defined, especially when you don't own/control the source to the original object.  He brought up "Why not just add a method to your own class?" We've been going round and round (in a good way). My general response is that it is another tool in the toolbelt, and his response is it is a useless waste of a tool... but I thought I'd get a more "enlightened" answer.  What are some scenarios that you've used extension methods that you couldn't have (or shouldn't have) used a method added on to your own class?


We know that dna is an acid which is elaborated by deoxyribo nucleic acid.It has 4 nucleo bases.Now,the question arises, why dna has no uracil base?

What is the advantage gained by the substitution of thymine for uracil in DNA?  I have read previously that it is due to thymine being "better protected" and therefore more suited to the storage role of DNA, which seems fine in theory, but why does the addition of a simple methyl group make the base more well protected?


I want to publish the title of last uploaded videos of my favorite channels on my blog.  Is there any feature on YouTube for that?

The default "Subscriptions" feed on the YouTube homepage shows all of the activity of the people that I am subscribed to on YouTube or have in circles on Google+. However, I'm most interested in new videos that the people I subscribe to (either on YouTube or by circling on Google+) create and post (neglecting comments or sharing other people's videos - what you see when you check the "show uploads only" checkbox on the YouTube homepage). However, being able to bring anything off of the YouTube homepage and into Google Reader as an RSS feed would be good.  Is there a way to do this?


I'm reading the following book: .  In page 26, they attempt to prove the following theorem using Induction:     For all $n \in \mathbb{N}$:   $$1 + 2 + \cdots + n = \frac{n(n+1)}{2}$$   In order to prove the theorem we need to prove the following statements:   $P(0)$ is true. For all $n \in \mathbb{N}$, $P(n)$ implies $P(n + 1)$.   Proving the first one is easy:  $$P(0) = 0 = 0 * (0 + 1) / 2$$ $$= 0 = 0 * 1 / 2$$ $$= 0 = 0 / 2$$ $$= 0 = 0$$  In order to prove the second, they state the following:  $$1+2+\cdots + n + (n+1) = \frac{n(n+1)}{2} + (n+1) \tag{1}$$ $$ = \frac{(n+1)(n+2)}{2} \tag{2}$$  I don't understand how they get from (1) to (2) and how that proves that proves that for all $n \in \mathbb{N}$, $P(n)$ implies $P(n + 1)$ is true.  I'm clearly missing something in the process. Can someone clear the fog for me?

I am currently studying proving by induction but I am faced with a problem.  I need to solve by induction the following question.  $$1+2+3+\ldots+n=\frac{1}{2}n(n+1)$$      for all $n > 1$.  Any help on how to solve this would be appreciated.    This is what I have done so far.  Show truth for $N = 1$   Left Hand Side = 1  Right Hand Side = $\frac{1}{2} (1) (1+1) = 1$  Suppose truth for $N = k$  $$1 + 2 + 3 + ... + k = \frac{1}{2} k(k+1)$$  Proof that the equation is true for $N = k + 1$  $$1 + 2 + 3 + ... + k + (k + 1)$$  Which is Equal To  $$\frac{1}{2} k (k + 1) + (k + 1)$$  This is where I'm stuck, I don't know what else to do. The answer should be:  $$\frac{1}{2} (k+1) (k+1+1)$$  Which is equal to:  $$\frac{1}{2} (k+1) (k+2)$$  Right?  By the way sorry about the formatting, I'm still new.


I left my bone broth out after pressure cooking for 3 hours. It was warm when I got home and consisted of a chicken carcass, lamb bones with a bit of meat and the second boiling of marrow beef bones with some vinegar. It gelled so perfectly in the fridge but should we eat it? Would boiling it again for a while make it safe?

If I left food out of the refrigerator for some period of time, is it still safe? If I left it out too long, can I salvage it by cooking it more?


I'm wondering if there is a historical explanation as to why the New in "New York" is pronounced /nu/ (as in "Noodles") rather than /nju/ (as in RP "New Year").  Has this always been the case? Or did the pronunciation change over time?

My coworker and I have been having this discussion for a day or two...  What is the most correct way to pronounce 'new' or 'news' ?  Does it rhyme with 'few' ? or 'snooze' ?  Does 'new crew' rhyme?  I know both 'noo' and 'nyoo' are correct, but what are the origins of the two different pronunciations?  Asking around the office, it seems that 'nyoo' might have a British English origin, but I would like to know if anyone is more knowledgeable on this topic.


I'm running MacOS Mojave.  For months, I have the following file in my bin which I'm unable to remove:  ~/.Trash/Recovered files #1/(A Document Being Saved By Quick Look Helper)/thumbnails.fraghandler  Stuff I've tried:  sudo rm -rf ~/.Trash/Recovered\ files\ \#1/(operation not permitted)  chflags uchg thumbnails.fraghandler(operation not permitted)  chmod the directory (operation not permitted)  I can move the file to another folder (e.g. Desktop), but unable to remove it from there as well.

I have this file (see attached);   And I cannot delete it. it doesn't exist...  I have tried typing rm in the prompt then dragging the file on to it, I have gone to the actual location of the file and it's not there, I have deleted .Trash folders left right and center and I still can't find it... I have just run First Aid on ALL the volumes I have and the file still mocks me. Does anyone else have any suggestions?


How do you get these arrows in math mode? Is there a standard command or package?

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?


It isn't too hard to show that there are infinitely many non-invertible matrices, and finitely many invertible ones. But how do we find all the possible matrices?  Edit : The other question has not given all the matrices.

The question is:  If A is a square matrix such that $A^2=A$ then $A^n =A$ for all natural numbers $n$  greater than one. What is $A$ if $A \ne 0$ and $A \ne I$.   I figured out an answer but I can't tell if that's the only answer. Let's say that $a_{kk}$ is a value in $A$. Every value in $A$ is $0$ except for $a_{kk}$ and $a_{00}$, they're $1$. I haven't gotten this answer mathematically.  I've tried a few approaches but ended up with the identity matrix.


There were a group of kids (3 or 4) and they were joined by a Chinese girl from a well off family. I remember they visited a plant and something about flies buzzing in their brains at the end where she betrayed her shipmates or something. There was something about having 'encoded cards' that they got on the black market.

I'm looking for a sf story that was broadcast on BBC children's TV in the early 1980's, probably as part of the long running Jackanory series. Based on what i recall of other events at the time of watching I think this was 1982. The story is of a group of children who are either orphans or in a boarding school and who build a spaceship from the scrap of other ships and (I think) an asteroid. They launch it into space and have subsequent adventures. One scene that particularly sticks in my mind was the oxygen failing on the ship and the children all falling asleep except for a girl who is bullied by a robot into fixing the problem. I'm reasonably sure that the author of the stories would be British as it was an adaptation for the BBC. I also have a feeling that this was adapted from a series of children's books with each volume being compressed into one episode. It ran Monday to Friday for one week. I vaguely recall a female narrator. The story was interspersed with still drawings and acted scenes with children. I'm looking for the title of the story (stories) in either TV or book form and the author. Note, the description of acted scenes and drawn illustrations makes this sound like Captain Zep: Space Detective, another BBC show. It was not this one although they would have been made at similar times. Hope there is enough detail here for a answer. Thank you!


Which basic physics principle could I use to formulate a simple explanation of the homogeneous distribution of electric charge on the surface of a hollow metallic sphere?  P.S.: targeted audience with no background in physics.

If the charge $q_1$ has to repel the charge $q_2$, the electric field has to go inside the conductor which contradicts the fact that electric field inside conductors is zero. Then why do the charges distribute themselves in a particular manner? Why can't they be distributed over a small place on the conductor?


Is there a singleton design which can completely prevent the creation of more than one object?  Asking this question keeping in mind that, in Java, we can recreate 'singleton objects' using serialization-deserialization and reflection.

What is an efficient way to implement a singleton pattern in Java?


This is a minor bug which I noticed while reviewing..  I accidentally pressed backspace when the review question poped up. I then pressed forward to go back to review question, and I found that NEXT button now no longer functions.. See image below        Notice there are duplicate question message appearing on screen which is uncommon.  Then, I just did refresh and ISSUE seems to be resolved.. see image below..        I did term this as minor bug because it in no way affected the site functionality or did stop me from reviewing(after refresh of-course..)   Steps to reproduce bug   Go one screen back by clicking back or backspace button. then again go forward to the review question screen. Buttons dont work then.   Can we look to solve this...

These are the steps to reproduce what I noticed.   I clicked on the link to review the suggested edits, and I was given  as post to review I clicked on "Skip" to pass to the next I was taken to  I clicked on "improve" by mistake When I noticed that, I clicked on the back button to go out of the edit page   After I did that, I was shown the previous post to review, but in that page the review buttons didn't work. What I described happens even in the case the suggested edit is already approved/rejected; in that case the "next" button doesn't work.  Is this a bug, or is it expected to happen?  It happens in Firefox 17, and Safari 6.0.1, and Google Chrome 22.0.1229.94. Stack Exchange revision is 2012.10.20.4492.


You will see here:    What is the trick with modulus for proving irrationality?  What about $\sqrt{2}$  Can you prove this is irrational by that trick?

I was reading Ian Stewart's Concepts of Modern Mathematics.     Using congruences, It's possible to explain why all perfect squares end in $0,1,4,5,6,9$ but not in $2,3,7,8$.    With this I had the idea of exploring the congruences for both sides of $n^2=2m^2$ in Mathematica:  Table[Mod[n^2, 9], {n, 0, 20}]  Table[Mod[2 m^2, 9], {n, 0, 20}]  And had the results:  {0, 1, 4, 0, 7, 7, 0, 4, 1, 0, 1, 4, 0, 7, 7, 0, 4, 1, 0, 1, 4}  {0, 2, 8, 0, 5, 5, 0, 8, 2, 0, 2, 8, 0, 5, 5, 0, 8, 2, 0, 2, 8}  But I'm still not sure if the outputs really show what I'm looking for, I have also tried $mod \;10$. The idea is still pretty loose in my mind, I'm stuck on deciding if this proves something or what directions I could take in this enterprise.


I made the mistake of installing Windows 10 after installing Linux (Kubuntu 18.04).  How can I make Grub the controlling boot loader at this point without disturbing either of the existing installations?  Most of the discussion of this subject seems to assume that one or the other of the systems has been installed, but not both.  If the existing setup boots into Windows, how do I get Grub installed?  (I also have a live Kubuntu on a memory stick.)  Update: I've been able to get into my Kubuntu system by pressing Esc on power-up, which on this particular machine (HP Pavilion) gives me a choice of where to boot from.  Kubuntu and Windows are the two important choices.   But I still can't get the machine to boot directly into grub.  I've installed and run Boot-Repair.  It completed successfully but didn't solve the problem.  Further Update: I've finally gotten the dual boot to work, but I did it the scorched-earth way: I completely cleared the disk by installing a new partition table with gparted, reinstalled Windows 10 and then reinstalled Kubuntu 18.04. My conclusion is that if you're in a bad initial state, fixing the problem is almost impossible unless  you have specialized knowledge.  Most of the fixes proposed in this forum are dependent on a favorable initial state.

I have Ubuntu on my laptop. Now I want install Windows 7 in a dual-boot. How can I do this? I can't lose my Ubuntu files, and I'm afraid that I might break . Go  for UEFI only!


A function $f : I\to \mathbb{R}$ is convex on an interval $I \subseteq \mathbb{R}$ when $\lambda f(x) + (1 − \lambda)f (y) \ge f (\lambda x+(1 − \lambda)y )$ holds for all $x,y \in I$. Prove $$ \sum_{i=0}^n \lambda_i f(x_i) \ge  f\left(\sum_{i=0}^n \lambda_i x_i\right) $$ holds for all $n\ge 2, x_1, \ldots, x_n \in I$ and $\lambda_1, \ldots, \lambda_n \ge 0$ satisfying $1 =  \sum_{i=0}^n \lambda_i$.  My Attempt: If $\lambda_1>0$ then I take $\lambda_0 = \lambda_1 + \lambda_2$ and $\Lambda_1 = \lambda_1/\lambda_0, \Lambda_2 = \lambda_2/\lambda_0, x_0 = \Lambda_1 x_1 + \Lambda_2 x_2$ and $$ \lambda_0(\Lambda_1 f(x_1) + \Lambda_2 f(x_2)) + \sum_{j=1}^n \lambda_i f(x_i). $$ Pls help me on what to do next and how to complete the proof

I want to prove that     Suppose there is a function $f:[a,b] \to \mathbb R$, and there are $x_i \in [a,b], w_i \gt 0 $ for $i=1,\dots,n$ such that $\sum_{i=1}^nw_i=1$, then if the function is convex, the following inequality holds $$\sum_{i=1}^nw_if(x_i) \ge f(\sum_{i=1}^n w_ix_i)$$   and if the function is concave, flip the sign of inequality.   Please include (very) detailed explanation, because I do not have much mathematical maturity, and perhaps may not be able to understand what the equation defining convex means if the explanation is too concise.


I have a list of objectsList<Batch> batchesList new List<Batch>();with fields  string orderNo and int lineNo   I print "orderNo-lineNo"  I want to sort it by orderNo then lineNo. The problem I have is that using linq's sort(), this will sort as a string, thus 11AG131-13 would actually come before 11AG131-2  batchesList.Sort((x, y) => (x.orderNo + x.lineNo).CompareTo(y.orderNo + y.lineNo));   Thanks for help

I have two tables, movies and categories, and I get an ordered list by categoryID first and then by Name.  The movie table has three columns ID, Name and CategoryID. The category table has two columns ID and Name.  I tried something like the following, but it didn't work.  var movies = _db.Movies.OrderBy( m => { m.CategoryID, m.Name })


Or should it be without the second "to" like this: "A manual written to help students understand the module"? I'm guessing that either is generally acceptable but is there a traditional grammar rule about this? Thanks

What is the correct way to use infinitive after the verb "help": with or without "to"?  For example:     Please, help me to understand this.   or:     Please, help me understand this.


I've been experimenting with lights in Blender 2.8, and I came across a curious situation. When working and rendering with Eevee, adding or subtracting lights responds accordingly (i.e. no lights, dark render. add lights, lit objects render appropriately depending upon placement and number of lights).  If however, I switch over to cycles for a comparison render, every object seems to be lit up whether there are lights in the scene or not. Renders the same way. Adding or subtracting lights makes no difference. It's almost as if the objects were 'emissing' their own light, but this makes no sense as plain objects I add to the scene without texturing or materials do the same thing.  Is there a setting I am missing when I switch between the two? I've been through most of the settings, but it just doesn't seem to make sense. Has anyone else experienced this? Thanks...

I am making a house in Blender Cycles. In rendered mode, all shaders are somehow visible, even though I don't use any lamps. I do have an environment texture, however it shouldn't light up the inside of the house. Especially when there are no windows. Even if I set the background strength to 0, it still lights up the inside and outside of the house.  So now, if I add any lamps, I has nearly no impact on shadows, shaders, reflections etc. What could be wrong with my scene?  Let me know if you have any questions on my settings that might help you find the problem.  File:   These are the world settings:   For the Ambient occlusion I always use this node:   It usually works fine.


I know it is probably silly question but I did not found the answer. I use ubuntu 16.04 and the terminal colors are just black and white even if using ls ll etc. The .bashrc file doesn't contain any content about the terminal colors for some reason. How can I set the terminal colors to match those in 18.04 version? (green usr name blue current path colored folders files etc.)  I tried to change some things on the preferences menu but it didn't help to solve the issue.

Is it possible to change the colors in the command prompt for the user@computer, as well as the the current directory and command parts of the prompt display?   I've already seen something like this done by OSX users, but I don't know how to do the same thing in gnome terminal (I can only change foreground and background colors).   It'd be very useful when, for example, trying to compile programs that have errors, since long, unformatted messages make it hard to distinguish which lines are commands and which are output.


If we send a photon away from earth, it would eventually reach a comoving distance of about 16.5 billion light years (the universe's event horizon). I'm interested in how far (in comoving distance) particles moving below $c$ can eventually travel and at what velocity they would arrive if they were to reach a distant comoving galaxy near the end of this journey.  A simple answer to both would be that a particle moving at $kc$ (where $0<k<1$) could eventually travel $k$ times as far as light could. This is what I get if I assume $v_{peculiar}$ is always equal to $kc$ and $v_{recessional} = H(t) \cdot distance(t)$ (both in proper coordinates) and take the integral of velocity over time to get the distance.   However, I've also heard that the momentum of a particle reduces as it travels, resulting in redshift for photons (since they can't lose velocity) and in velocity loss for other particles. It seems that this could affect the above calculations. For example,  says $\frac{\dot{p}}{p}=-H$.  Does this mean that a particle launched at $kc$ would instead travel less than $k$ times 16.5 billion light years and arrive at a galaxy near that limit with a relative (proper) velocity near zero?  (Bonus points if you could derive an equation for the the maximum distance as a function of $k$.)

Suppose you have an object some distance from you and moving at a velocity different to the Hubble velocity you'd expect at that point. How does the motion of this object change with time? Does it travel in a straight line (i.e. geodesic), and if you wait long enough how far will it get?


I'm writing a Windows/Mac app, it is the same as a mobile app I have. I have no experience releasing PC apps, only mobile apps. On mobile I know how to monetize with ads and sales, but on PC I have no idea what the preferred methods are. So, which Stack Exchange site would be the right one to ask that type of question?

So much I don't know.  Would love to be able to ask, learn, and discuss as I do in your other forums.


It just came to my attention that when flagging (not VTC) a Question as duplicate one is presented with the following options:    As we can see, among those is the "a duplicate..." option. However, if we select the "should be closed..." option instead, we are presented again with an option to flag as duplicate:      I wonder what is the reason for the redundancy in that specific option? Are users more prone to select "should be closed..." instead and thus justify including the option there as well?

We've changed the flagging format from today(AFAIK) as below,        looks good.  But, when I select it should be closed for another reason...  I can see the same reason duplicate on the top.        What is the need of placing that reason over there? It should not be there. Please remove the dupe.


I tried to make guacamole the other day and it completely failed because some of the avocados that I bought were not ripe. How can I know which avocados to pick in order to make good guacamole?

I've been trying to ignore my burning desire to make some guacamole because every time I go to the supermarket to buy avocados I can't manage to pick out good ones.  They always either become too soft before I have a chance to do anything with them or are hard and not very tasty.  How can I tell when an avocado is perfectly ripe?


Is there an easy way to accomplish something like this:  I am aware this is scanned, what I want is the random ink distribution and character placement.

Is there a way to simulate imperfections of some of the older books in LaTeX? Like the missing pieces of letters, extra splotches of ink and such?  Here is an interesting artifact:   P.S.: I guess one way would be to get an old printer haha :-0


It is the default version of the imagemagick program convert that comes with ubuntu 14.04  ip-173-31-35-119:~ [prod]$ convert -version Version: ImageMagick 6.7.7-10 2014-03-06 Q16 http://www.imagemagick.org Copyright: Copyright (C) 1999-2012 ImageMagick Studio LLC Features: OpenMP      In another shell I have downloaded the latest version of source code and compiled locally.  If I start a new shell, I can see  $ bash - ip-173-31-35-119:~$ convert -version Version: ImageMagick 6.9.2-3 Q16 x86_64 2015-10-07 http://www.imagemagick.org Copyright: Copyright (C) 1999-2015 ImageMagick Studio LLC License: http://www.imagemagick.org/script/license.php Features: Cipher DPC OpenMP  Delegates (built-in):    So the new binary is already available.  In both shell, they report the same result from which and ls -l:  $ which convert /usr/local/bin/convert ip-173-31-35-119:~ [prod]$ ls -l /usr/local/bin/convert -rwxr-xr-x 1 root root 6336 Oct  7 20:11 /usr/local/bin/convert   Why the first shell seems to still running the old version of the binary? How can I clear this?

When looking for the path to an executable or checking what would happen if you enter a command name in a Unix shell, there's a plethora of different utilities (which, type, command, whence, where, whereis, whatis, hash, etc).  We often hear that which should be avoided. Why? What should we use instead?


Here is the code below:  #include <stdio.h>  int main() {   printf("Stack Overflow");   main(); }   After compiling and executing this program it will print "Stack Overflow" until its stack overflows. Here, I know what a stack overflow means, that means it will print until memory is full. My question is which memory is it? What is the size of the stack that is overflowing?

Programming language books explain that value types are created on the stack, and reference types are created on the heap, without explaining what these two things are. I haven't read a clear explanation of this.  I understand what a stack is. But,    Where and what are they (physically in a real computer's memory)? To what extent are they controlled by the OS or language run-time? What is their scope? What determines the size of each of them? What makes one faster?


Let $\alpha\in\mathbb C$. Recall that $\mathbb Q[\alpha]$ = {${f(\alpha) : f(X) \in \mathbb Q[X]}$} and that $\mathbb Q[\alpha]$ is a vector space over $\mathbb Q$.  Suppose that $\mathbb Q[\alpha]$ is finite dimensional as a vector space over $\mathbb Q$. Prove that $\alpha$ is algebraic over $\mathbb Q$.  I'm not sure where to start with this proof, so any help is much appreciated. Thanks!

If $[L:K]$ is finite, then $[L:K]$ is algebraic.  The author's proof is to simply state that given $[L:K] = n$, then ${1, x, x^2, ... , x^n}$, for any $x$ in $L$, would contain $n+1$ elements, so it must be linearly dependent over $K$.  First of all, why must ${1, x, x^2, ... , x^n}$ be linearly dependent over $K$? I do undertsand that if $L=K(a_1, ... , a_m)$, and we pick an non-algebraic $a_i$, then ${1, a_i, a_i^2, ... , a_i^n}$ would be, by definition, linearly dependent over $K$. But how can we know that this works with all the elements in $L$?  Second of all, even if we find that $c_0+ c_1x+c_2x^2 + ... + c_{m-1}≠0$, for some $x$ in $L$, $c_i$ in $K$, why would this mean that $[L:K]=∞$?    I asked this question a couple days ago, though I didn't explain my doubt in such detail as in this post. Anyway, the replies asked if I understood the meaning of being 'linearly dependent over a field $F$'. My understanding is that a set ${b_1, ... , b_n}$ is linearly independent over $F$ if each element in $F$ can be written as $f_1b_1+...+f_nb_n$ (so that  the different combinations of $b_i$ form the whole $F$) and that the only way $f_1b_1+...+f_nb_n=0$ is for all the $b_i$ to be $0$ (so that we make sure all the elements in the set are needed to map create $F$).  I guess they asked me that question because is rather obvious why the author's proof works. Yet I don't know why, but it isn't that obvious to me.    I would really appreciate any help/thoughts.


So I'm doing a bit of practise in database design, and a question arose that I couldn't figure out how to correct.  I'm pretty new at this, so I'm not the best but here it goes.  So I want to create two different tables, one called Team, and one called Player. These tables are pretty different from one another.  I then want another table called Challenge, which I want to reference either Team or Player.  Basically there are competitions, and they are either competed individually, or as a team. I want a foreign key to reference Team, if its a team challenge, or Player if its individual.  I can't combine the two tables, as they contain very different elements.  Im just a bit confused as to how to do it. Can I have just one foreign key, that will reference one table or another. Or shall I have two, with one null.   Or can I add another ID key in the Team and Player. And then in Challenge if a new Type key indicated its a group, it'll reference Team, and if its individual, it references Player.  Again, pretty new at this, so hope I made sense.

Well here's my problem I have three tables; regions, countries, states.  Countries can be inside of regions, states can be inside of regions.  Regions are the top of the food chain.  Now I'm adding a popular_areas table with two columns; region_id and popular_place_id.  Is it possible to make popular_place_id be a foreign key to either countries OR states.  I'm probably going to have to add a popular_place_type column to determine whether the id is describing a country or state either way.


I have not worked with 3d coordinate systems for a while and this is giving me a bit of a struggle. I have the coordinates of four points in XYZ. Two points I use to generate the line AB and the other two I use to generate line CD. I would like to find the closest XYZ coordinate on AB to line CD and the closest XYZ coordinate on CD to line AB. My idea was to find the equation for the perpendicular line between AB and CD and then find the intersection of this new line with AB and CD. However, I do not really know where to begin. If anyone could help that would be very much appreciated

I have two arbitrary lines in 3D space, and I want to find the distance between them, as well as the two points on these lines that are closest to each other.  Naturally, this only concerns the skew case, since the parallel and intersecting cases are trivial.  I know how to find the distance, as the question was asked before and answered .  I haven't found a good explanation on how to find the two points that determine that distance, though.  So specifically, given two lines  $$L_1=P_1+t_1V_1$$ $$L_2=P_2+t_2V_2$$  I would like to find two points $X_1$ on $L_1$ and $X_2$ on $L_2$ such that the distance between $X_1$ and $X_2$ is minimal.


Can someone clarify whether or not a capacitor blocks current at DC?         – Schematic created using

I am confused with this! How does a capacitor block DC?   I have seen many circuits using capacitors powered by a DC supply. So, if capacitor blocks DC, why should it be used in such circuits? Also, the voltage rating is mentioned as a DC value on the capacitor. What does it signify?


I am trying to change a node color of Tikz node with only option as:  \documentclass[10pt,xcolor=dvipsnames,xcolor=table]{beamer} \usepackage{tikz} \usetikzlibrary{positioning,arrows} \usetikzlibrary{decorations.pathmorphing} \usetikzlibrary{decorations.markings} \begin{document} \begin{frame}     \centering     \begin{tikzpicture}[sibling distance=12em, level distance=3em,         every node/.style = {shape=rectangle, rounded corners,           draw, align=center, font=\footnotesize,     top color=Red, bottom color=Red, color=white}]]     \node {Foo}     child {node{Bar1}}     \only<1>{child {node{Bar2}}     \only<2>{child[top color=Blue] {node{Bar2}}       child {node{bar21}}     child {node{bar22}}};   \end{tikzpicture}  \end{frame} \end{document}   This works fine when no only thing is involved, but with only, its giving error:  Runaway argument? \centering \begin {tikzpicture}[sibling distance=12em, level distance\ETC. ! File ended while scanning use of \frame. <inserted text>                  \par  <*> mwe.tex   What I am doing wrong here? Please help.

I have a diagram of 4 nodes in my beamer slide.    \begin{figure}[h]   \begin{centering}   \begin{tikzpicture}[system/.style={draw,rectangle,rounded corners=3,minimum width=2cm,text width=1.8cm,text centered}]     \node [system] (fe) {Feature Extraction};     \node [system] (am) [right=of fe] {Acoustic Model};     \node [system] (lm) [right=of am] {Language Model};     \node [system] (d) [below=of lm] {Decoder};      \draw[->] (fe) |- (am);     \draw[->] (am) |- (d);     \draw[->] (lm) -- (d.north);    \end{tikzpicture}   \end{centering}   \end{figure}   How can I in a second slide "highlight" one of the nodes, like I can do with <alert@n> for a item in a list?  With highlighting I mean for example giving a color and thickening the lines.


I had previously hosted my domain in a different instance in a different aws account but for some reason I had to delete that aws account  and create a new one. I am now trying to host my domain in the new instance. So I went to my registrar`s account and deleted all the nameservers from the domain name and added the new nameserver. Then I added my domain into the hosted zone in aws.   After waiting for 2 3 hrs my domain is still now working but if I visit the public IP it works.  I have edited the /etc/hosts file and added domainname.com there and also I have edited the /sites-available/default and added       server { #        passenger_ruby /usr/bin/passenger_free_ruby;         rails_env development; # add this if you get error like “Incomplete response received from application” from nginx / passenger         listen 80 default_server;         server_name fuitter.com, *.fuitter.com;         root /usr/share/nginx/html/maggie/public/;          # You must explicitly set 'passenger_enabled on', otherwise         # Passenger won't serve this app.         passenger_enabled on;     }   I have restarted my nginx server but still it is not working. security group then, in inbound rule I have set HTTP to anywhere and SSh to custom ip and in outbound i have set all traffic to anywhere. Is there anything wrong with this?

I have updated a domain name DNS zone on 123-reg.co.uk where I bought the domain name. I have only updated blog A record to different hosting(IP)   On my PC home (windows) or another PC in the same network (MAC or phone) when I visit the blog.domain.com still shows old IP address (hosting).  But when I connect to 4g on my phone or try from different network, they visit new IP (hosting)  I did ipconfig /flushdns I have restarted the router at home. I have cleared browser cache  Why do you think the reason is? How can I solve this?   Thanks.


I have to go to school.  I have to go to the school.  Which is correct sentence?  Can we use article before the word "School"?

Why is this sentence wrong about the article usage?     Don't be late for the school.   I was told that the correct sentence is Don't be late for School.


$a,b,c \geq 0$ and $a^2+b^2+c^2+abc=4$ prove that $ab+bc+ac-abc \leq 2$ can any one help me with this problem,I believe Dirichlet's theorem is the key for this sorry for making mistake over and over again,but i'm certain that the inequality is true now.

Let $a,b,$ and $c$ be nonnegative real numbers such that $a^2+b^2+c^2+abc = 4$. Prove that $$0 \leq ab + ac + bc - abc \leq 2.$$   I tried using rearrangement to get $a^2+b^2+c^2+abc = 4 \geq ab+bc+ac+abc$. Then I just need to show that $0\leq ab + ac + bc - abc$ and $4-2abc \leq 2$. I am not sure if this method will work, though.


I got two JavaScript objects. I want to compare both objects to one another. If object 1 has a key which is missing in object 2 add this key to object 2.  But this must also be the case if object 2 has a key which is missing in object 1.  So for example, object 1 looks like this.  var object_1 = {     "Address": "Address",     "AccessDeniedText": "You do not have access to the page you requested.<br>Use the navigation menu on the left to select a page you want to open.",     "Basket": "Shopping cart",     "BasketVAT": "VAT {0}"     ... };   object 2 looks like this.  var object_2 = {     "Address": "Address",     "Basket": "Shopping cart",     ... };   In object 2 the key AccessDeniedText and BasketVAT are missing.  Expected result What i now want is to have an new object, lets say object 3 that would now output the following.  var object_3 = {     "Address": "Address",     "AccessDeniedText": "",  // I can fill this missing text     "Basket": "Shopping cart",     "BasketVAT": "" // I can fill this missing text }   I tried to use $.each() and for(key in object). However, this made my whole browser crash. Not so wierd, because each object has more then a 1000 rows.  I also tried to awnser of this question:  It didn't work for me.  Is there a simple way to do it? Without my browser crashing of the heavy payload? I dont care using jQuery.

I need to be able to merge two (very simple) JavaScript objects at runtime.  For example I'd like to:  var obj1 = { food: 'pizza', car: 'ford' } var obj2 = { animal: 'dog' }  obj1.merge(obj2);  //obj1 now has three properties: food, car, and animal   Does anyone have a script for this or know of a built in way to do this?  I do not need recursion, and I do not need to merge functions, just methods on flat objects.


Normally, we say      "He was caught with his mistress."   Here, we know that the male is a married person. The meaning is clear.   If he is not married, then we can say     "He was caught with his girlfriend."   But, how to convey that a married female was caught with her lover.     a female was caught with her ____.   Saying that, she was caught with her boyfriend does not clear the air that she is married or not.   So, is there any male-gender specific word opposite of mistress and clears the air that female is cheating her husband?   I googled few words:  lover, sweetheart, loved one, love, beloved, darling, dearest, young man, man friend, man, escort, wooer, admirer etc.  And, from Wikipedia,     "Paramour" is sometimes used, but this term can apply to either partner in an illicit relationship, so it is not exclusively male.   But, none fits the requirement.

The mistress definition, Oxford dictionary     a woman having an extramarital sexual relationship, esp. with a married man   I am looking for the male equivalent of 'mistress' as defined above. Some sources on the net come up with 'master' and 'mastress'. But I could not find both words in dictionary as male equivalent of mistress.  So, any male equivalents of mistress in formal English?


It started few days ago. I'm running sudo apt update command and it never ends. Terminal output is  Get:1 http://ru.archive.ubuntu.com/ubuntu xenial InRelease [247 kB] Hit:2 http://archive.canonical.com/ubuntu xenial InRelease                      Hit:3 http://ppa.launchpad.net/attente/java-non-latin-shortcuts/ubuntu xenial InRelease Hit:4 http://ppa.launchpad.net/webupd8team/sublime-text-3/ubuntu xenial InRelease Ign:5 http://dl.google.com/linux/chrome/deb stable InRelease                    Hit:6 http://ru.archive.ubuntu.com/ubuntu xenial-updates InRelease              Get:7 http://security.ubuntu.com/ubuntu xenial-security InRelease [94,5 kB]     Hit:8 http://dl.google.com/linux/chrome/deb stable Release                      Hit:9 http://ru.archive.ubuntu.com/ubuntu xenial-backports InRelease            Fetched 341 kB in 2s (150 kB/s)   While this proccess system fan speed is boosted on my laptop and it's kinda annoying to listen to this. There is no excessive cpu activity though. Can you guys hint me why it happens?

I tried to install crossover and after downloading the .deb from their website, I followed the steps as indicated when opening it with Ubuntu Software Centre:     On 64-bit flavors of Debian and some Ubuntu variants, first open a   terminal and run sudo dpkg --add-architecture i386 ; sudo apt-get update   Since I have Ubuntu 16.04 LTS 64 bit I perform the command.  But when copying and pasting that command into my terminal, it stopped at Fetched 535kb in 7sec and stalled there for about 20 minutes. I ended up  closing it and tried to run both commands separately but after doing the sudo apt-get update command it also stalls again after "Fetched XXKb in XXsec."  I restarted my computer and decided to run the software updater and it stays stuck at roughly 75% for hours.


I have a 14.4v NI CD power drill with a charger that outputs 18v 400mA (original charger for drill) but the charger supply lead no longer works. Looking to get a replacement but finding it difficult to get an exact match The charger voltage output (18v) is larger than the voltage of battery (14.4v) but does the output amps have to be the same as original (ie 400mA) if not what amps could i go upto?

Power supplies are available in a wide range of voltage and current ratings.  If I have a device that has specific voltage and current ratings, how do those relate to the power ratings I need to specify?  What if I don't know the device's specs, but am replacing a previous power supply with particular ratings?  Is it OK to go lower voltage, or should it always be higher?  What about current?  I don't want a 10 A supply to damage my 1 A device.


I would like to know the derivation of the general equation of a conic:  $$Ax^{2} + Bxy + Cy^{2} + Dx + E y + F = 0$$  I have searched over the internet, but I did not find any resource which doesn't make use of trigonometry.

Let me start with some basic definitions:  Definition 1. A conic section is the curve resulting from the intersection of a plane and a cone.  Definition 2. A  conic  section  is  the  set  of  all  points  in  a  plane  with  the  same  eccentricity  with respect to a particular focus and directrix.  Definition 3. A conic section is the set of points $(x,y)$ satisfying the implicit formula  $$Ax^2+Bxy+Cy^2+Dx+Ey+F=0$$  All these definitions are familiar to me and they are taken from a paper of Mzuri S. Handlin, Conic Sections Beyond $\mathbb{R}^2$.  Now, in by university textbook I have the following theorem,     Theorem.  Any conic has an equation of the form      $$Ax^2+Bxy+Cy^2+Dx+Ey+F=0$$      where $A,B,C,D,E$ and $F$ are real numbers and $A,B$ and $C$ are not   all zero. Conversely, the set of all points in $\mathbb{R}^2$ whose   coordinates $(x,y)$ satisfy an equation of the form that above, is a   conic.   Proof to this theorem is omitted, and reference are not included. I've been searching for a proof, but failed to find one.  It seems that the above theorem make motivate us to define definition 3, right?   If one can provide me a reference for the proof of the theorem or sketch guidelines for possible proof?  Thank you.


DJ didn't have the rose broach thing that Maz said he'd have, but I had the feeling that nevertheless he was the person they'd been sent to find and maybe the guy they saw with the broach had either stolen, won and bought the broach from DJ who was clearly in some kind of desperate situation (i.e. in jail and presumably broke). And Maz had said there was only one person (she knew of) that could break them on to the First Order's ship and DJ did actually do that...  Is there any evidence to support DJ being the person they were looking for? Or was it just sheer luck that they happened to find the only other person that could break them in that Maz didn't know about?

In The Last Jedi, Finn and Rose are tasked with finding "the master code breaker" by Maz. They travel to the city of Canto Bight and after searching      think they found him by the unique lapel pin he wears.    However, they are then apprehended by the local security and thrown into jail where they meet     another character (played by Benicio del Toro, I think the character is DJ?) who seems to fit the role of master code breaker based on his actions.    Then later once aboard the First Order ship      DJ betrays Finn and Rose by selling them out. Which seems out of character for someone loyal to Maz.    So my question is who was the "real" master code breaker that Maz has told Finn and Rose about? The one they thought (based on lapel pin) or the one they actually ended up with?


I have abstractly thought of Pure Linux as a just Linux which has only basic functions.  What is the exact definition of Pure Linux?  How far is it different from Ubuntu or something ?  How can I download the Pure Linux image?(I want to install it on virtual machine)

I was going through an article on GNU which goes something like below     There really is a Linux, and these people are using it, but it is just   a part of the system they use. Linux is the kernel: the program in the   system that allocates the machine's resources to the other programs   that you run. The kernel is an essential part of an operating system,   but useless by itself; it can only function in the context of a   complete operating system. Linux is normally used in combination with   the GNU operating system: the whole system is basically GNU with Linux   added, or GNU/Linux. All the so-called “Linux” distributions are   really distributions of GNU/Linux.   I always thought Linux as a kernel and Operating System but it looks like Linux = Linux kernel and GNU OS.   Could someone point out the exact functionality of each in the "Linux" terminology we use in our day to day life. Also, according to the wiki, GNU's design is Unix-like but differs from Unix by being free software and containing no Unix code. I thought Unix is opensource. Isn't it?


Apache 2.4.x :    prefork event worker     What are the conceptual differences between these three? What are the types of applications or each or situations in which each MPM is useful?

This is a  about selecting the right Apache httpd MPM.   I'm a little confused between the different MPMs offered by Apache - 'worker', 'event', 'prefork', etc.  What are the major differences between them, and how can I decide which one will be best for a given deployment?


I'm running some scripts to check the UFW status and would like to run sudo ufw status without having to do sudo. I was hoping to find a firewall or ufw group to add myself to, but I didn't find any.   How can I allow any user X to do the ufw status without being root or asking for sudo password?    UPDATE:   I wanted to try to add my own file to /etc/sudoers.d/, but was lazy so decided to copy one already existing, like this:  sudo cp /etc/sudoers.d/mintupdate /etc/sudoers.d/firewall_status   Don't do That! You will not be able to do sudo or login again. I had to do a boot recovery. Instead use:  sudo visudo -f /etc/sudoers.d/ufwstatus   Now just follow the accepted answer below.

On one particular machine I often need to run sudo commands every now and then. I am fine with entering password on sudo in most of the cases.  However there are three sudo commands I want to run without entering password:   sudo reboot sudo shutdown -r now sudo shutdown -P now   How can I exclude these commands from password protection to sudo?


Well as you can figure out, most primates such as monkeys, gorillas and chimpanzees, have all their body covered with fur. As we know they are evolutional "relatives" to us humans, but we dont have much hair(only on the head,on the armpits, on the groin, etc.). I would like to know why this "evolution" happened in a such brief era and why.

The little amount of body hair humans have don't seem to be of much use for keeping warm. Our Simian cousins on the other hand sport thick furs.  At which point during the species evolution and why did humans lose their fur?


I have factory method that returns Type of a POCO given a Key.       public static Type GetType(string key)     {         var name = string.format("MyPOCOClass{0},MyAssembly",key);         return Type.GetType(name);     }   So lets say value of the Key is One and assume that the class MyPOCOClassOneexists in MyAssembly  in above case i wanted type of IEnumerable<MyPOCOClassOne> How do i do that?

The title is kind of obscure. What I want to know is if this is possible:  string typeName = <read type name from somwhere>; Type myType = Type.GetType(typeName);  MyGenericClass<myType> myGenericClass = new MyGenericClass<myType>();   Obviously, MyGenericClass is described as:  public class MyGenericClass<T>   Right now, the compiler complains that 'The type or namespace 'myType' could not be found." There has got to be a way to do this.


This is my first day after upgrading from 17.04 to 17.10. I've noticed that xdotool is not working as it used to. For example:  xdotool type "Lorem ipsum" types nothing.   xdotool key ctrl+shift+t doesn't open a new tab in gnome-terminal.  xdotool mousemove 0 0 doesn't move the mouse.  xdotool click 1 doesn't click on the stuff under the mouse.  xdotool getactivewindow windowmove 100 100 doesn't move the active window and returns an error:   XGetWindowProperty[_NET_ACTIVE_WINDOW] failed (code=1) xdo_get_active_window reported an error   What I found is still working:   xdotool search --classname Navigator windowactivate does activate the browser.  xdotool getmouselocation --shell returns info about mouse position.  xdotool selectwindow does allow me to click on a window to get its id.  I have some scripts that rely on this tool. Any suggestion how to fix this?  UPDATE: I'm using Wayland display manager. Switching to Xorg makes it work again. Is it possible to make xdotool work again while still using Wayland?

Need to bind an F key to perform Ctrl-S in Gedit and reload page browser. Can't get xdotool to find Gedit window on Ubuntu 17.10  $ xdotool search --name "Opera" | tail -1 58720257 $ xdotool search --name "Gedit" | tail -1 $    Tried changing search string to "Text Editor", file name, etc. xdotool can't find only Gedit. Works for any other desktop window. It's always the active window so finding that would also work.


When I try to ask a question, I receive the message:     Oops! Your question couldn't be submitted because:      Sorry, we are no longer accepting questions from this account.   And strangely when I logged in on Ubuntu everything was fine. What's the problem?

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 dun goofed. I thought my Windows was booting using UEFI, and I installed Ubuntu using UEFI. But now I think my Windows was booting using MBR, and GRUB can't detect it.  I'm confident the disk is MBR:  > sudo gdisk -l /dev/sdb GPT fdisk (gdisk) version 1.0.3  Partition table scan:   MBR: MBR only   BSD: not present   APM: not present   GPT: not present   and that I'm booting via UEFI:  > ls /sys/firmware/efi/ config_table  fw_platform_size  runtime      systab efivars       fw_vendor         runtime-map  vars   How can I fix my GRUB so that it boots using MBR instead of UEFI?  I've tried:   Running os-prober and update-grub Running boot-repair    Neither gave me a GRUB menu with Windows listed.

I have a dual boot of Windows and Ubuntu. When I switch on the machine, the BIOS does POST and after that the bootloader starts.  I want to understand how the BIOS chooses which bootloader to run. I want to know the process going on between the BIOS and the bootloader in a dual boot computer.


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

Is it possible to create an instance of a generic type in Java? I'm thinking based on what I've seen that the answer is no (due to type erasure), but I'd be interested if anyone can see something I'm missing:  class SomeContainer<E> {     E createContents()     {         return what???     } }   EDIT: It turns out that  could be used to resolve my issue, but it requires a lot of reflection-based code, as some of the answers below have indicated.  I'll leave this open for a little while to see if anyone comes up with anything dramatically different than Ian Robertson's .


The whole diagram shifts up when more children are added in the second level. Is there a nice way to adjust this automatically, so that the top nodes do not change their position from one slide to the next? For example, see slide 1 and 2 in the following code: (Thanks in advance) \documentclass{beamer} \mode<presentation>{\usetheme{Madrid}}   \usepackage[style=verbose]{biblatex} \usepackage{tikz} \usetikzlibrary{shapes.geometric, arrows} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \tikzset{startstop/.style = {rectangle, rounded corners, minimum width=3cm, minimum height=1cm,text centered, draw=black, fill=red!30}} \tikzset{io/.style = {trapezium, trapezium left angle=70, trapezium right angle=110, minimum width=3cm, minimum height=1cm, text centered, draw=black, fill=blue!30}} \tikzset{process/.style = {rectangle, minimum width=3cm, minimum height=1cm, text centered, text width=3cm, draw=black, fill=orange!30}} \tikzset{decision/.style = {diamond, minimum width=3cm, minimum height=1cm, text centered, draw=black, fill=green!30}} \tikzset{arrow/.style = {thick,->,>=stealth}} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \title[tikzpicture with beamer]{}  \begin{document} \begin{frame}{tikzpicture}{} \begin{tikzpicture}[node distance=3cm]  \node (root) [process] {root}; \node (child1) [process, below of=root, xshift=-4cm] {child1}; \draw [arrow] (root.south) -- (child1.north);  \node (child2) [process, below of=root, xshift=0cm] {child2}; \draw [arrow] (root.south) -- (child2.north);   \node (child3) [process, below of=root, xshift=4cm] {child3}; \draw [arrow] (root.south) -- (child3.north);  \node<+(1)-> (child21) [process, below of=child2, xshift=-3cm] {child21}; \draw<.(1)-> [arrow] (child2.south) -- (child21.north);  \node<+(0)-> (child22) [process, below of=child2, xshift=3cm] {child22}; \draw<.(0)-> [arrow] (child2.south) -- (child22.north);  \end{tikzpicture}     \end{frame}  \end{document}

This question is essentially the same as one of my , except the only difference is that I am using "only" to change the text at the same location (i.e., ). In other words, I am destroying my earlier text as I go, and not adding new ones underneath the previous ones.   Since the text for the first "only" is shorter than the second "only", therefore the image will shift location. I would like for the image to remain at its location.   Here is an example     it may not be obvious but the second image is higher up than the first.  The code is here, can someone find a solution?  \documentclass{beamer}  \usepackage{graphicx}  \title[Title]{Presentation} \author{Sandro Botticelli} \institute{Italy} \date{1484}  \begin{document}   \begin{frame} \begin{figure} \includegraphics[scale = 0.8]{Venus}     \caption{Nascita di Venere} \end{figure}  \only<1>{In the centre the newly-born goddess Venus stands nude in a giant scallop shell. Its size is purely imaginary, and is also found in classical depictions of the subject. }    \only<2>{Alternative identifications for the two secondary female figures involve those also found in the Primavera; the nymph held by Zephyr may be Chloris, a flower nymph he married in some versions of her story, and the figure on land may be Flora. Flora is generally the Roman equivalent of the Greek Chloris; in the Primavera Chloris is transformed into the figure of Flora next to her, following Ovid's Fasti, but it is hard to see that such a transformation is envisaged here.} \end{frame}   \end{document}


So suppose I go to like  or  there's gonna be a bunch of stuff like say [UTCDate "2018.01.03"] [WhiteElo "2706"] [BlackElo "2940"]  How do I get this data into a spreadsheet like column 1 is all the dates, column 2 is the corresponding white elo, column 3 black elo, col4 white username and col5 black username?  Update 2: Fixed now. see the 'json' vs the 'preformed'. WOW. Update 1: It appears Mike Steelson has an answer , where the code is given as =arrayformula( regexextract(split( substitute(substitute(substitute(getDataJSON(A1;"/games";"/pgn");"[";"");"]";"");"""";"") ;char(10));"\s.*") )  with an example given here  It appears there's a problem when it gets to the case of chess960 only. Consider for example : Replacing 'gmwso' with the player's username will yield a weird output. i imagine the output will be messier for mixed chess960 and chess.

Both  and chess.com have the feature to play the variant  live. However, only lichess has a graph showing how your live chess960 rating has changed over time. Lichess also shows other statistics like highest, lowest, best wins, worst losses, average opponent rating, etc. (chess.com does have this for correspondence chess960 though.) I could create my own graph and statistics in Excel/Google Sheets by manually recording each game's date and my rating afterwards indicated beside my username, but... Question: Is there a way to obtain, or what in general is the way to go about obtaining, ratings after each chess960 game using some kind of script that sees a player's public profile and then extracts the data? I have a feeling this kind of script has been done before even if this was not specifically done for chess.com's live chess960. The script doesn't have to graph (pretty easy to do once you have to the data: just use excel/google sheets). I just need the script to collect all the dates and rating numbers for each line of the user's games.  Update 2: Fixed now. see the 'json' vs the 'preformed'. WOW. Update 1: It appears Mike Steelson has an answer , where the code is given as =arrayformula( regexextract(split( substitute(substitute(substitute(getDataJSON(A1;"/games";"/pgn");"[";"");"]";"");"""";"") ;char(10));"\s.*") )  with an example given here  It appears there's a problem when it gets to the case of chess960 only. Consider for example : Replacing 'gmwso' with the player's username will yield a weird output. i imagine the output will be messier for mixed chess960 and chess.


I'm using Minecraft Java version 1.12.2. I have a fake player called Alive that shows the amount of players still active inside the arena. When a player loses a round that counter will lower by 1. When the count reaches 1 the game will stop (don't worry about that; I already know how to handle this). The problem I'm having with this is that I don't know how to tell a command block to keep an active count of the number of Alive players.  Does anyone know how to count players within a radius and set that for the score of the fake player Alive?

I want to run a command when there are only 10 entities left. I know you can use /execute unless entity to detect when all matching mobs have died, but it doesn't work if you want to run a command when there are for example 10 entities left.  A command like /execute if entity @e[limit=10] does not work, it also triggers if there is only one entity.  Such a counting system could also be used to determine once there is only one player left in an arena, meaning they have won a battle or similar.


I can understand the need to audit editing etc and when I get the first user and first answer privileges the system seemed to work well.  However I just unlocked close votes and now it seems that every third vote I do is an audit. That is just annoying and feels like an enormous waste of my time and doesn't really encourage me to put any effort into trying to clear the enormous backlog of close votes stack overflow has.  So I was already getting a bit annoyed by it, and then I got an audit:   The answer from OldCurmudgeon came up in the audit to be reviewed and it was indeed an excellent answer. However the process failed because I went and read the question and saw the answer was already there! So I hit flag to report that the answer was a duplicate of an already posted answer...and got told that I should be paying more attention?  So I get told I should pay more attention because I was paying too much attention?  What does the audit failed actually mean? Beyond being a slap in the face for trying to help what does one or two failed audits actually do in real terms?

I just had a review queue audit question "fail" because I clicked "Close" on a post that the community felt should be left open. This particular meta question is about the close vote review queue, but the same principle should apply elsewhere.  Audits are good. I see what the idea behind them is, and for the very most part I agree wholeheartedly. However, just clicking "Close" in the review queue doesn't actually do anything. All it does is bring up a dialog box with a bunch of options for how to close the question. Nothing of significance happens until you actually vote to close.  I often pull up that dialog box to refresh my memory if I am uncertain what is considered on topic by the community on various sites. For example, product recommendation questions are off topic on SuperUser but not on Unix & Linux. On the other hand, on Unix & Linux non-reproducible problems are specifically off topic, which they are not on SuperUser (though posts about nonreproducible problems may be off topic for other reasons). Since there can be quite a bit of overlap between the sites, sometimes I'd rather just check to be sure before deciding to leave a question open. There have been a number of times when actually checking has made me decide that a question really is not off topic where it was posted; it might have been off topic on a different site, but it's fine on this one according to the earlier judgement of the community.  However, unless you really go out of your way, before you're able to make that determination you have already failed the audit.  If the issue at stake is (as has been indicated previously) that  in voting, that can easily be detected (handled, mitigated, fixed, ...) by putting in some random votes in the audit "close" dialog box, or not displaying any votes at all in the case of audits. Or even possibly showing exactly such a set of "wrong reason" votes. The reason for that being that what one should be trying to catch is people taking action based on incorrect judgment, which is quite different from just clicking on the "Close" button quite possibly without even a clear intention (see above about the memory refresher).  Hence:  In a review queue audit, only actually doing something that would ordinarily result in taking action should cause you to pass or fail the audit. That is, for example, clicking "Close" in the outer view shouldn't fail you even if the question should be left open, although clicking "Vote To Close" in the resultant dialog box should.


According to refractive index's formula, we say that speed of light is other mediums is smaller than that of speed of light in air/vacuum. What quantum mechanical effects govern the increase in speed of light when it moves from another medium back into air/vacuum?

As I learned today in school, my teacher told me that when light enters a glass slab it slows down due to the change in density and it speeds up as it goes out of the glass slab. This causes a lateral shift and the light emerges out from the point different than that from where it should have actually emerged from.  Okay so what I mean to ask is, when light enters point A on glass slab and emerges from point C why does the light speed up? Where does it get the energy it has lost when it entered the glass slab?  P.S.: Also, if I place a very very very large glass slab and make a beam of light pass through it will the light never come out as all the energy was lost in place of heat?


I have a list that needs to contain a variable number of independent sets.  When I run the following piece of code, I want to add the string "testing" to only the first set.  numberOfSets = 3     test = [set()]*numberOfSets test[0].add("testing") print test   However, when I print test, it shows three identical sets that all contain testing. How can I set up my list so I can separately access each set?

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


I searched a lot for static variables in python but could not find a direct answer  . Just as java would have a variable defined as static within a class , can the same be done for python?

Is it possible to have static class variables or methods in Python? What syntax is required to do this?


If I connect to TS over RDP and after that run application which resides on SBS 2003 server (shared app directory), do I need to buy SBS 2003 CAL beside TS CAL?

This is a  about Licensing.    Questions on licensing are off-topic on Server Fault.  If your question has been closed as a duplicate of this question, then this is because we want to help you understand why licence questions are off topic rather than just telling you "it just is". In all likelihood, this question will not address your question directly, it was not meant to.    I have a question regarding software licensing. Can the Server Fault community please help with the following:   How many licenses do I need? Is this licensing configuration valid? What CALs do I need to be properly licensed? Can I run this product in a virtual environment? Can I downgrade this product to an earlier version? Am I entitled to feature X with license Y?


While reading  written by Grant Fritchey, I found it difficult to understand the following part: avoid RAID 5 for t-logs because, for every write request, RAID 5 disk arrays incur twice the number of disk I/Os compared to RAID 1 or RAID 10.  I know that RAID 5 differentiate from other RAIDs with its parity feature. It means that if some of the drives fails, then it is possible to recover lost data from the other drives. I want to understand why it is not recommended to use RAID 5 for a transaction log file. Explanation in the book was not enough for me to get it. Maybe someone could explain it to me or provide a good article.

We are trying to evaluate the potential performance improvements that could be gained by switching an existing applications .mdf files to a RAID10 LUN vs. the existing RAID5 LUN they are living on right now. The transaction log already lives on a RAID10 LUN.   So the question is, if we move data files to RAID10 would the end user see performance improvements in the GUI? or would it be just faster writes to the data files when a checkpoint occurs and the changes get written to the data file but no improvement would be seen at the end user level?