As noted in  question, the concepts of heaven and hell appear to exist in the galaxy far, far away;  Han even mentions the latter in The Empire Strikes Back:  RANDOM JERK REBEL GUY:  Your Tauntaun will freeze before you reach the first marker! HAN SOLO:  Then I'll see you in HELL!  The modern concepts of heaven and hell have their origins in the so-called Abrahamic religions:  Christianity, Judaism, and Islam. Therefore, since the galaxy far, far away has heaven and hell, it is logical to ask if the galaxy far, far away has some concept of the Abrahamic god. Adding fuel to the fire, DVK's answer  notes that Han's freighter contains a compartment he hasn't been able to open.  The ID number on the compartment is identical to the ID number on the crate in which the Ark of the Covenant is stored in Raiders of the Lost Ark.  Surely, if a holy relic associated with the Abrahamic god of Judaism is referenced (and perhaps located) in the galaxy far, far away, it is sensible to ask if that same god is known to some of the galaxy's inhabitants in some form or another.   Does the concept of the Abrahamic god of Judaism, Christianity, and Islam exist (in any form, or to any degree) in the galaxy far, far away? Note 1: I don't think this is addressed in the movies, and although I would prefer a canonical answer, Legends will do, if nothing else is available.  However, the Star Wars Holiday Special is not an acceptable source. Note 2:  The substance of this question is fundamentally different from "Do Heaven and Hell exist in Star Wars", because that question and its answers don't address the Abrammic god in any way.

In The Empire Strikes Back as Han Solo leaves to look for Luke Skywalker a rebel worker says     Your tauntaun will freeze before you reach the first marker.   Han replies     Then I'll see you in hell!   Is there a concept of heaven and hell in the Star Wars mythology? If not, to what is he referring?


A while ago, I think, I started hearing and reading people use the verb 'to sit' incorrectly, but it seems to becoming increasingly common.  Such as "I am sat", "We are sat", "They were sat". Sit is a pretty regular verb. The perfect form of it (sat) is the only irregular form of it, so it makes this doubly odd.   For instance:      Never is this more literal than when you are sat in front of the telly watching Gogglebox.         Wondering where you will be sat?        Feels like yesterday we was sat in college moaning to finish   Could this error be deliberate, as a form of inverse snobbery (attempting to appear mainstream)? This might also be a particularly British thing, rather than American. Certainly all the examples I can see online seem to be from British (typically colloquial) sources.

Is "I am sat" bad English? I believe it is incorrect and instead either the present continuous     I am sitting   or the predicate adjective     I am seated   should be used.  I hear this quite often, however, and ultimately usage overrules formality.  Does anybody know where this originated or how to describe it grammatically?


I'm just starting regular expression for python and came across this problem where I'm supposed to extract URLs from the string:  str = "<tag>http://example-1.com</tag><tag>http://example-2.com</tag>"   The code I have is:  import re  url = re.findall('<tag>(.*)</tag>', str)  print(url)   returns:  [http://example-1.com</tag><tag>http://example-2.com]   If anyone could point me in the direction on how I might approach this problem would it would be most appreciative!  Thanks everyone!

I have this gigantic ugly string: J0000000: Transaction A0001401 started on 8/22/2008 9:49:29 AM J0000010: Project name: E:\foo.pf J0000011: Job name: MBiek Direct Mail Test J0000020: Document 1 - Completed successfully  I'm trying to extract pieces from it using regex. In this case, I want to grab everything after Project Name up to the part where it says J0000011: (the 11 is going to be a different number every time). Here's the regex I've been playing with: Project name:\s+(.*)\s+J[0-9]{7}:  The problem is that it doesn't stop until it hits the J0000020: at the end. How do I make the regex stop at the first occurrence of J[0-9]{7}?


I play Minecraft 1.12.2 Java edition. I made a command block that basically shows a welcome intro (ex: Welcome to the world! Please ask  for creative mode.) I want it to repeat about every 30 seconds. I made a HUGE chain of redstone repeaters that takes up A LOT of space. It works, but I was wondering if there was any other easier way.

I found 11 questions like this on gamingSE already, but none of them have proper and up-to-date answers. So I'm creating this Q&A:  How do you either activate a command x seconds/minutes/hours/… in the future or every x seconds/minutes/… in a loop?  Repeating command blocks and ticking functions execute 20 times per second, redstone is  in many situations and most of the extremely fancy solutions, like falling blocks in cobwebs, have broken over time or are needlessly complicated.


Can anyone help in proving this statement. I have thought and tried but can't seem to do it. Let $(X,T)$ be a topological space and let $A$, $B$ be two closed subsets of $X$. If $A\cup B$ & $A\cap B$ are connected, then show that $A$ is also connected.

Let $X$ be a topological space. Let $A$ and $B$ be two subsets of $X$ such that: $A$ and $B$ are closed, $A \cup B$ is connected, $A \cap B$ is connected     Prove that $A$ and $B$ are connected.   Thoughts:  Suppose that $A$ is disconnected. Since $A$ is closed, there are two non-empty, disjoint, closed sets $E$ and $F$ in $X$ such that $A = E \cup F$. Then I attempted many things but all were not really useful.  Please help. Thanks.


I am using an array in conjunction with a curve modifier to make a stone wall along a path.  But the problem is that it is easily noticeable that all the stones have the exact same mapping (i.e. the exact same cracks in the exact same place) which looks terrible.  This problem is easy to eradicate for just the displace modifier by basing the texture coordinates on an empty.  I would like to be able to do something like this for the material mapping as well, altering the position of the UV pelt on the UV grid.  Though I am open to any suggestions on how to fix this problem.  Edit:  As a clarification, I need to use UV coordinates, not generated.

Using the array modifier and textures, can the individual array objects be slightly textured differently for individual look?


From experience (in-game, and through discussion), it is generally advised not to store gear/treasure in a random barrel in a cave, because   Obviously because you can easily lose where that barrel was More specifically, because the game can "reset" in that area, and delete your stash.   Is there actually any evidence that can be found to prove this (other than just situational), so I know where I can/cannot set up a "base". I.e. is there anything in the code (or elsewhere) that might indicate the difference between "Breezehome", an Inn, or a random cave?

I'd like to find a place to store stuff while I'm out adventuring, without spending 5000 on a house (at least, until I can afford that...). Where can I safely store items without worrying about them disappearing?   There are two possible places that come to mind,  (to which I have the key and was told I could stay), and the small bedroom given to me at the  (which I was told was mine, despite seeing J'zaro sitting in it later). Can I store items safely in either of these places?


I just wanted to know if it was possible to model a microwave resonator in spice software or somehow import it from somewhere to spice to carry out analysis.  Also if it is not possible to model the microwave resonator in spice, will using a series or parallel resonance circuit be able to 'replace' the microwave resonator/cavity. I would be grateful for any help.

Hi I am new to SPICE and after doing some research into the spice software, I need some help understanding which type and how to model microwave cavities in SPICE. I want to model a microwave cavity in SPICE, however I will need to use an equivalent structure, can I just use an LC circuit to do this ?. The microwave resonator I am trying to model is just the cavity used in labs.


I am installing RAGE on my PC, after installing it fully I go to play and Steam wants me to download 17.9GB, would that be updates or what? I cant play until I download that and my internet is capped and I cant download is there away around this??

Is is possible to install a steam game and then play it without having to download a huge update file?  I'm temporally on super slow broadband at my parents and want to play a game I got now, not in 10hours :-/  Thanks


"dick" has developed a lot of meanings. Pons.eu lists five different meanings. The semantic development of most of them can be understood, but  "dick all/dick" for nothing is a bit mysterious (AmE, slang). Does anybody know more about this American slang use?   He doesn't know dick all. He doesn't know dick about us. Tomy Clancy, USA, The Teeth of the Tiger.

Damn all, Bugger all, Sod all etc., etc. What does all mean here? How did the expression originate? Was there a single original term (expletive or not) preceding all in this usage?  At the risk of overbroadening the question, does the underlying linguistic mechanism that gives rise to this expression generate others that are very similar? And are there close parallels in other languages?


I had a few .mov video files in channel 1, and it rendered fine, but then I tried to add an mp4, and I got an error (xyz.mp4 could not be loaded), so I decided to add some .jpg images instead.  The images rendered fine, but when they weren't on screen, it would render as black. Even when I removed the images, it would render as black.  I tried duplicating one of the strips from the first channel and putting it into the second channel (hoping is was just an issue with the channels), and it still had that issue.  But when I added a new .mov, it would render that one fine, but it wouldn't fix the other strips.

I started using Blender couple of weeks ago to edit some of my video clips. Spent quite a while editing this one, and everything worked fine. Video rendered as it should. The whole project consists of a MP4 file with a whole lot of soft cuts. Came back to it a couple days later and now the preview won't show a thing. When I render the scene, it's just a black screen with no sound.  The original file is still working, as well as my other Blender projects. And the weirdest thing is that if I add a new movie clip to the project, the preview works just fine for that clip.  Can anyone guess what might have caused this? I've googled like crazy and haven't found anything helpful.


It seems that I can't delete my account from certain SE sites.  I have for many years had several accounts I don't use and am at the moment only active on Physics while I wish to keep a profile on only a few others.  On the user profile pages on the sites, there is a button called Edit Profile & Settings. After clicking the side menu gives several options, one of which is Delete profile... But on some sites this button is just gone.  For example I am unable to delete my account on ,  and  (this latter one is in beta).  How come that some sites are trying to hang extra much on to me? How do I delete my account on those?

How can I delete my Stack Exchange account(s)? Also,  What happens to my content? Can I request it be deleted as well? What if I'm suspended, rate-limited, or banned from posting questions or answers? What will happen to my votes? Will other users be impacted? Why wasn't my account deleted immediately after the timer expiring? What will happen to my pending bounties and close, reopen, delete, or undelete votes? I want my account deleted on all Stack Exchange sites. How do I do this? Will my profile on chat be removed once I delete my site account?   For more information, see "" in the .


I have updated my profile on SO by changing my Display Name, and today i have tried again to change my Display Name, but it showing the following error message:    What it make sense ?? that error message is displaying after the user tried to change their name, (this is the case same as user jump into the well, after that you are saving their life and giving alert).  Instead, you should show the alert message while the user is changing their Display Name or updating profile.

The policy on changing one's display name :  only one display name change is allowed every 30 days  However, there is no warning whatsoever when actually changing one's display name.  Thus, it came as quite a bit of a shock to me when I found out today that I might be stuck as "Unicorns are Yummy" on Stack Overflow for the next freakin' month. I would like to recommend that a warning be added to the "Edit Profile" page to warn people. Or, at least make the policy concerning display name changes more obvious. Workaround I was able to change my display name back (phew!) by copying my profile from Meta Stack Overflow. I still think a warning should be implemented, though.


I have an image, and in order for it to look good i need to make the width bigger that the part of the page where I am suppose to add text, so it gets shifted to the right. Is there a way to center it, even if it is too big (I am fine with it going beyond the margin, but I want to do so equally on both sides). Thank you!   This is my code  \begin{figure}[htbp]      \centering     \includegraphics[width=18cm, height=6cm]{Figure.png}      \caption{Caption}     \label{fig:outflow}  \end{figure}

I have a figure that is wider than the \textwidth of my document. (I don't want to change the \textwidth.) As a result, the leftmost part of the figure is flush with the left margin, while the rightmost part spills into the right margin too much. I'd like to center the figure, so that it will exceed the \textwidth equally on both sides.


I’ve noticed that, from time to time, my total reputation points are changed, generally for small  amounts: 5, 10 or 20 points for instance. The issue is not the adjustment itself but I wonder  how that comes about. There is no evidence of these adjustments in  “reputation” or “votes” summaries such as “user was removed” and the like. Apparently no visible action was taken. So my question is, are there reputation adjustments possibly made by the system, probably on old posts, that result only  in the change in the total reputation count  without any visible action to users?

If I am concerned that my reputation score is incorrect, how can I audit it, or get a report of a detailed breakdown of my reputation?


(This question was originally asked for my specific laptop: Dell XPS 15 L502X. But it seems that understanding I gained from the upgrade experience I am able help my friends to decide upgrading RAM their laptops of different models. If you dont have this specific laptop, you may hop on third-last paragraph starting as "While buying RAM you have to ensure that..." in the answer I have written.)  I bought my Dell XPS 15 L502X laptop almost 18 months ago. It has 4GB RAM and am thinking to upgrade it.  Processor: Intel 2nd Generation Core i7 2630QM   According to , it supports upto 16GB of DDR3 RAM at dual channel and at 1333MHz.  Currently I have 4GB 1333MHz DDR3 SDRAM RAM from Samsung. Running CPU-Z shows that it is a Single Channel:     Can I add , so that it will become total of 12GBs? I am concerned because the specs on the same page says Memory Configuration : Single Channel while at the same time says it is SO-DIMM. If it is a DIMM then it must be able to work in dual channels with others right? Am a bit confused. Do I need to do any configuration for that? or simply putting RAM in other slot will do?  post says that 2x8GB (total of 16GB) DDR3 1333MHz Corsair RAM worked on the same laptop model.  I am concerned about if I can setup RAM modules from two different manufacturers together in dual channel.  I also realized that the above mentioned RAM also has the same CAS latency as the one currently installed: 9-9-9-24.  From , I know that max supported RAM speed is 1333MHz, can I benefit from buying 8GB 1600MHz DDR3 SDRAM from Corsair? Can I use it in dual channel with my current 4GB DDR3 1333MHz RAM? Will I need to do any configuration for that? What is the different between   similar RAMs from Corsair, since they have different price tag? Second one specifies Memory Configuration : Single Channel in specs sheet, but the first one specifies none such parameter. Does that mean the first one can be used in dual channel with other DIMMs while second one cannot be? Out of these three (links in Q1 and Q3) RAMs from Corsair which one better suits to my situation?

If I want to add more RAM to my computer, how can I buy something compatible? What kinds are there? How do I determine which kind my computer will accept and how much I can add?


I am new to ubuntu. I recently updated my windows 10 OS and i also installed ubuntu from windows store and I am having trouble finding my C program files from compling it from this ubuntu.exe  Thank You!!

I have installed Ubuntu subsystem on Windows 10 (after enabling feature in settings), but where is the Ubuntu file system root directory located in the drive?


I was working with numbers recently and I had a situation where I want to set the precision of a double value say to 6 digits or 4 digits, depending on the value stored in the database.  For example, If in the database the precision is set as 4 digits then the output must look as,  10.0000.   I tried with DecimalFormat and using the string ##.####, but it is annoying to use symbols everytime.   Is there any better approach, say something like below:  Double value = 10.0; value.setPrecision(4);

What I would like is a method to convert a double to a string which rounds using the half-up method - i.e. if the decimal to be rounded is 5, it always rounds up to the next number. This is the standard method of rounding most people expect in most situations.  I also would like only significant digits to be displayed - i.e. there should not be any trailing zeroes.  I know one method of doing this is to use the String.format method:  String.format("%.5g%n", 0.912385);   returns:  0.91239   which is great, however it always displays numbers with 5 decimal places even if they are not significant:   String.format("%.5g%n", 0.912300);   returns:  0.91230   Another method is to use the DecimalFormatter:  DecimalFormat df = new DecimalFormat("#.#####"); df.format(0.912385);   returns:  0.91238   However as you can see this uses half-even rounding. That is it will round down if the previous digit is even. What I'd like is this:  0.912385 -> 0.91239 0.912300 -> 0.9123   What is the best way to achieve this in Java?


I have a correlation matrix A given below. Here A should be a positive-definite matrix so that we can perform Cholesky decomposition of A.  1.0,  0.5,  0.6,  0.7  0.5,  1.0,  ??,   ??  0.6,  ??,   1.0,  ??  0.7,  ??,   ??,   1.0   How to find the unknown correlation coefficients in A such that A will remain as positive-definite matrix without changing the given coefficients?

I have a question regarding correlation inference. Consider, I have two sets of variables X and Y. For an x element of X I know the correlation to an unknown variable z. I also have the covariance matrix X and Y. Moreover, I know a set of (y1,y2,y3) element of Y, which model best my variable x. So how to infer the correlation of (y1,y2,y3) and z?  I need a function: f(corr(x,z), corr(x,(y1, y2, y3)), cov(X,Y)) --> corr((y1,y2,y3),z)  This might be a very simple question, but I have no idea how to do it or for what I can search in the literature.  Thank you in advance!


When I create the function like this:     and whenever I put this script in any HTML element, it shows the recent post which is correct:     This is the  for the above one its working. But I want to manipulate the script src attribute but I cant achieve the result from it:

   This is the  for second one but not working.

Any idea why the piece of code below does not add the script element to the DOM?  var code = "<script></script>"; $("#someElement").append(code);


Facebook puts a little (1) in the page title whenever you have a comment, etc. I find this really handy when I have a bunch of tabs open, and it would be great on Stack Overflow too. So, could we get the development team to add this in? To clarify, when a notification or comment is received and shown as a number in a red/blue circle next to the Stack Exchange logo in the top bar, I think it would be a good idea to mirror that number in the page title, similar to the way Facebook does.

I understand a few similar questions have been asked, but this is hopefully completely separate functionality.  Say you have Facebook open in Tab 1 of your favorite browser (mine is Chrome). When someone posts on your wall, comments, adds you as a friend (the list goes on), you get a number in the title of the page(tab) saying Facebook(1), indicating some sort of activity. The same thing happens if you're ON the page itself, I presume there is a notification ticker of some sort.  I already love the new  logo which does show notifications but only when you refresh look at the page.  I often find myself at work answering a question here and there and then I forget about it and do some actual work. 4 hours later, I click on my profile and BOOM, you have 8 comments, probably because you forgot to .Dispose() of an object or something :)  If my Stack Overflow tab title showed something like      (4) What's your favorite C# book?   Or, for pinned tabs, a browser will also indicate the title changed:    It would attract my attention to go and see who's complaining about my answer, if the OP needs more information or whether someone is just happy with my post.  So rather than refreshing Stack Overflow on an hourly basis, could we automate this and make our lives easier?   What do you think?


I'm trying to do a simple IF check of a String that I know has been formatted correctly with:  Calendar c = Calendar.getInstance(); SimpleDateFormat df = new SimpleDateFormat("MM/dd/yyyy"); String formattedDate = df.format(c.getTime());   At this point formattedDate is "09/24/2015". I can confirm that this is true:  remoteViews.setTextViewText( R.id.widget_date, formattedDate);   It's showing me the correct date.  So I know it's good. So I test it:  if (formattedDate=="09/24/2015"){ //do some stuff }   For whatever reason, that condition is not true, and nothing happens. I have tried everything from removing the slashes, to just changing the format around, but formattedDate never equals what that string clearly is.  Is there something I'm missing here?

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 have a file with assets that we bought for some game. They are organized in "groups" - parented to empty objects. There are many many of these "groups" with another "groups" inside of them. How do I find where the object is?  Fastest way I found is to select all the elements by hand in viewport and then in outliner use Search - Selected, unparent objects so they're outside of groups.  Clicking all the elements by hand is the main issue though. I'd like to select a building for example, and have it automatically selected in outliner so it's easy to select other elements grouped with it in outliner instead of selecting in viewport.  Photoshop does what I like - when object I click is in group, Layers panel opens this group and focuses view on that object layer. It should be like that in Blender imo. :< Any plugin for that or simple workaround?

How can I jump to the selected object in the out-liner, I've got over 200 objects in my scene, all named cube.___ ... and I can't seem to find my selected object. How can I jump to it?


I want to copy and paste a file to /usr folder but I guess I need root access to do so so I need to learn how to copy and paste a file from one location to another through the terminal.

I have read about copying files with terminal but these examples will help me a lot. So here is what I want to do:  Examples:   I have a file in /home/levan/kdenlive untitelds.mpg and I want to copy this file to /media/sda3/SkyDrive and do not want to delete any thing in SkyDrive directory. I have a file in /media/sda3/SkyDrive untitelds.mpg and I want to copy this file to /home/levan/kdenlive  and do not want to delete any thing in kdenlive directory  I want to copy a folder from home directory to sda3 and do not want to delete any thing on sda3 directory and opposite I want to cut a folder/file and copy to other place without deleting files in that directory I cut it into.


I think below two function result will be same, but it is not.  def fib2(n):   return n and n < 2 or fib2(n-1) + fib2(n-2)  def fib3(m):   return m if m < 2 else fib3(m-1) + fib3(m-2)   When argument value is 4, fib2's output is 7, fib3's output is 3. Why this situation happen? I don't know about this. My Python version is 2.7.9 and os is osX 10.11.1

If Python does not have a ternary conditional operator, is it possible to simulate one using other language constructs?


Let $\{f_k(x)\}_{k=0}^\infty$ be a Littlewood-Paley decompositon, that is,  $$ f_k \in C_c^\infty $$  $$ \sum_{k=0}^\infty f_k (x) = 1,$$ $$ \text{supp} f_0 \subset \{ |x| \leq 2 \},$$ $$ \exists f \in C_c^\infty   \; \text{such that}\; \text{supp} f \subset \{ 2^{-1} \leq |x| \leq 2 \} \; \text{satisfying}\; f_k (x) = f(x/2^k).$$ Then I hope to show that there exist $C, C'>0$ such that $$ C' \sum_{k=0}^\infty \| f_k(g) \|_{L^2}^2 \le \| g \|_{L^2}^2 \le C \sum_{k=0}^\infty \| f_k(g) \|_{L^2}^2$$ for $g \in L^2 (\mathbb R)$. Here $C_c^\infty$ means $C^\infty$ functions with compact support and $\text{supp}$ means the support.

Let $f_j \in C_c^\infty$ and assume there exists $M>0$ such that $\text{supp}f_0 \subset \{ |x| \le M \}$ and $\text{supp} f \subset \{ 1/M \le |x| \le M \}$. Define $f_j$ by  $$ f_j (y) = f(y/2^j) $$ for $j =1, 2, \cdots$. Suppose that $$ \sum_{j=0}^\infty f_j (x) = 1.$$  Then how can I show that there exist $C, C'>0$ such that$$ C' \sum_{j=0}^\infty \| f_j (g)\|_{L^2}^2 \le\| g \|_{L^2}^2 \le C \sum_{j=0}^\infty \| f_j (g)\|_{L^2}^2?$$ $C_c^\infty$ means $C^\infty$ functions with compact support and $\text{supp}$ means the support.


Background   I was recently away from home for about two weeks.  On some of the sites I moderate I wasn't the only one, so we were already down a little on moderator attention.  While I wasn't going to pay as much attention to SE as usual, I was hoping to help out some.  Unfortunately, using my phone I couldn't even see flags, let alone handle them.  Now some flags would be hard to handle on a phone anyway, but some are easy (yeah, delete that; no, decline that; etc).  And even seeing the rest would make discussions in the mod chat room easier.  Request  On the mobile interface we can see the diamond notification for new meta posts, mod messages, and SE announcements.  That's good.  Could we also have the flags notification, the one that leads to the flags page?  I don't think we want to try to jam the in-page flags overlay into the mobile interface; there just isn't room for that.  But for tempoary use on a phone, the following workflow seems quite acceptable to me: (1) Go to flags list. (2) Read a flag and then click through to read the post. Make a decision. (3) Use the "back" button to go back to the flags page and handle the flag.  I wouldn't want to do that all the time or when using a keyboard and mouse, but for a touch interface with limited real-estate this seems ok.  This also means that if I want to discuss the flag with other mods, I can copy the URL of the flagged post and head off to chat.  Note that I am asking for this in the mobile web interface, not the Android or iOS apps.  That would be ok too, but I've not had much luck navigating efficiently in the Android app so I don't use it for my regular browsing, just for notifications.  Note also that I am aware of the "use desktop site" option in mobile browsers, but that's quite unworkable for me at that screen size.  I tried that once or twice while I was away but quickly gave up.

I spend a great deal of time surfing SE sites from my phone during commutes and other down times. The global inbox is quite effective at reaching me even for chat pings. Quite frankly the mobile site is very well done!  However as a community moderator, there is a whole class of information not getting through. There are no notifications for moderator flags! I can switch to the full site and see these but that is inconvenient for browsing, so I only end up checking for flags periodically.  Ideally the moderator tools should all be available in mobile templates, but as a stand-by it's reasonable to switch to the full view to handle flags, but flags would get addressed in a much more timely manner if I knew about them. As it stands I often come and go from the site without even knowing there are outstanding flags.  A simple flag counter added to the header next to the notification counter and linked to the tools page (which automatically opens the full version anyway right now) would fix this.


Suppose we have 5 studies of our choice with percentage in results. Can we perform meta analysis based on percentage, as mean, sd or other values are not reported in any of those studies.


Suppose I have a fair coin that I will flip 100 times. Obviously the expected outcome is 50 heads and 50 tails.  This is what I want to know:  How can I find the probability of this expected outcome happening. In other words, what is the probability that, given 100 flips, my outcome will be EXACTLY 50 heads and 50 tails.

folks,  i am new to this forum and not a math expert. so please bear with me if am asking silly questions.   The question is "probability of getting 50 heads from tossing a coin 100 times".  So the answer for this is, I guess, ${100 \choose 50} (2 ^{-100})$.  So all am trying to get is easier way to calculate ${100 \choose 50}$, or another approach to the parent problem only.  Thanks all, appreciate that.  raj


I am trying to create a list of lists, and want to update only a particular sublist by indexing, but when i try to do it via the following approach, all other sublist's also get updated.  times=[0]*4 shows_times=[] for i in range(4):     shows_times.append(times)  shows_times[0][0]+=1 shows_times[0][1]+=1 shows_times[0][2]+=1 print(shows_times)   Output:  [[1, 1, 1, 0], [1, 1, 1, 0], [1, 1, 1, 0], [1, 1, 1, 0]]   But when i use the following code, i get the desired output.  shows_times=[] for i in range(4):     shows_times.append([0,0,0,0])  shows_times[0][0]+=1 shows_times[0][1]+=1 shows_times[0][2]+=1 print(shows_times)   Output:  [[1, 1, 1, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0]]   Please explain me why this behavior happens, has this anything to do with pass by value or pass by reference or something like that?

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?


Forgive me if  it seems simple but I couldn't figure it out easily. I thought about using a loop but was wondering if anybody knows an easier way: I have:  Map<String, Integer> map = new HashMap<>();          map.put("ClubB", 1);         map.put("ClubA", 2);         map.put("ClubC", 2);         map.put("ClubD", 2);         map.put("ClubE", 3);         map.put("ClubF", 2);         map.put("ClubG", 2);   I need to get keys or values at specific index in my tests. For example I need to get the key and value at index 3 etc. The reason is that I use a comparator and sort the Map and would like to show that the value at a specific index has changed.  Thanks for any ideas.  UPDATE:  I used:  HashMap leagueTable = new HashMap(); Map<String, Integer> map = sortByValues(leagueTable);   public <K extends Comparable<K>, V extends Comparable<V>> Map<K, V> sortByValues(final Map<K, V> map) {         Comparator<K> valueComparator = new Comparator<K>() {             public int compare(K k1, K k2) {                 int compare = map.get(k2).compareTo(map.get(k1));                 if (compare == 0) {                     return k1.compareTo(k2); // <- To sort alphabetically                 } else {                     return compare;                 }             }         };         Map<K, V> sortedByValues = new TreeMap<K, V>(valueComparator);         sortedByValues.putAll(map);         return sortedByValues;     }   I then used aloop to print out values:  for (Map.Entry<String, Integer> entry : map.entrySet()) {                      System.out.println( entry.getKey() + ", " + entry.getValue() ); }

I am relatively new to Java, and often find that I need to sort a Map<Key, Value> on the values.  Since the values are not unique, I find myself converting the keySet into an array, and sorting that array through array sort with a custom comparator that sorts on the value associated with the key.  Is there an easier way?


I am trying to find the smallest subring of rationals containing $p/q$, where p,q are relatively prime. I am constructing the subring from $p/q $ and I think rationals of form $pZ/q^k$ where k is whole number is the answer.  Am I wrong? Is there any general solution for $p/q$?  Edit: I am looking for a general solution for any $p/q$. There is no constraint that 1 should be in the subring.

Find all rings $R$ satisfying $\mathbb Z \subset R \subset \mathbb Z[\frac {1}{2}]$.   Solution: Let $f \in R$. Then $f= \frac {m}{2^n}$ for some integers $m,n$.  Since $2^{n-1} \in R$, hence $\frac {m}{2} \in R$. Hence one gets that $ \frac {1}{2} \in R$, so $R=\mathbb Z[\frac {1}{2}]$, so there is no ring $R$ satisfying given conditions.     What are the other possible solutions of this problem?    P.S: You can give a solution using any theorem from commutative algebra also.


This question is a result of a  posted on the Philosophy.SE Meta. Since it's a feature request, the moderators there recommended that I post my proposal here.  Badge conditions are the same on all StackExchange websites, while visitor numbers can be drastically different. This means that contributors on websites with a higher number of visitors can get badges more easily. Not only is this unfair, on some websites, many of the gold badges are literally unattainable. I understand that you might want to opt for more promotion of websites with a lower number of visitors rather than change badge conditions. However, I think some subjects will always attract less visitors than others.   Therefore, I believe it's a good idea to link badge conditions to the number of visitors once the number of daily visitors has stabilised.  Gold badges still should be difficult to obtain - that's the point - but they should be obtainable given the number of visitors of a specific SE website.

Many badges have fixed requirements, such as:   Answer score of 100 or more   However different websites means a different level of difficulty: the more active users a website has, the easier the badge is to get.  On a new and/or low-view website getting this badge may be impossible for several months; on a website like stack overflow now you can obtain it in a day, and it's relatively easy (compared to other SE sites).  Do you think it would be a good idea to implement a formula that allows the required score to scale? The more active users voting, the more votes are required to get it?  If yes how would you handle people who got it for a post that no longer meets the requirements?


I'm adding 0.5 to a number every second. However, it seems to be adding 0.5000000000001 instead.  window.setInterval(function() {     number += 0.5;     // it says number as 0.50000000001, and after 1.00000000002 }, 1000);   Does anybody know why this is happening?

Consider the following code:   0.1 + 0.2 == 0.3  ->  false   0.1 + 0.2         ->  0.30000000000000004   Why do these inaccuracies happen?


Please help me for some reason the Windows 10 icon isnt showing up. I have a Windows 8.1 It dosn't show up.Also i have all my updates installed. Please Help Me. i cant reserve a copy for Windows 10 and im really worried because like this is only for a limited time so if you know anything to fix Please Help Me Asap

I want to get Windows 10, but I do not see this icon in the notification area (tray):    How do I get the icon to get Windows 10?


How to reset the autoincrement field in Mysql data base?

I know that in MySQL at the command line I can reset a table's auto-increment field to 1 with this:  ALTER TABLE tablename AUTO_INCREMENT = 1   I am curious if there is a way to do this from within phpMyAdmin.  Something like a check box to reset the auto-increment or something else along those lines?  Not that there is anything wrong with the command line approach.  More one of those curiosity things I keep thinking on...  Thanks in advance!


Prove that $$|\frac{a-b}{1-\bar{a}b}|<1$$ if $|a|<1$ and $|b|<1$.  After doing some calculation I ended up in a dead end  $$|\frac{a-b}{1-\bar{a}b}|=\sqrt{\frac{|a|^2+|b|^2-(a\bar{b}+b\bar{a})}{1+|a|^2|b|^2-(a\bar{b}+b\bar{a})}}$$  How do I proceed further ?  Is there any alternating ways like using cauchy's inequality ?

$z\overline{w} \ne 1 $ Prove that $|\frac{w-z}{1-\overline{w}z}|\le 1$ if $|z|\le 1$ and $|w|\le 1 $. How to proceed this question?


Take a look at this image:    It appears the page's title's is made up of someTag, dash, question title, but what tag is someTag?  This question has three tags, yet it shows the singlepage tag out of all three, so what is the tag that appears in the page's title and why?

Over at ,    To this end, the tag listed first on a question (sorted by popularity of the tag)  So, what's the basis for tag popularity? Views? It sure as hell isn't number of questions.


How to factory data reset my Ubuntu ?I really love Ubuntu(Linux) but i think there should be a software to backup all my system settings just like windows. Thank you

I want to reverse all my Ubuntu modifications and return the system to factory settings. I've installed useless stuff and now I want to uninstall everything I manually installed/factory reset.. Is there a way to do that?  I read this article, , and it told me to run this:  sudo dpkg-reconfigure -phigh -a   Then this:  sudo apt-get install -f   But Ubuntu can't figure out even what the first one means. It tells me unknown option -a. If you have another way of reinstalling Ubuntu to factory settings I would love to hear it!


I have 2015 MBA running Catalina that at some stage in the past I managed to configure that when opening my own created dmg files (used for business data storage with encryption security) it no longer goes thru the verify process when opening - just straight to asking for the password. So I have bought a new MBA and installed Big Sur with clean install. Now I get the verify process each time I try to open my dmg files. Tried sudo defaults write com.apple.frameworks.diskimages skip-verify TRUE but it does not work. (In fact on my 2015 MBA, this flag is not set anyway). It is extremely time consuming to have to go thru the verify process every time I want to open (several) of my data dmg files. In response to a comment, I have set up a service as a work around that executes an automator service using shell script: hdiutil attach -noverify "$@" However, I find that I need to run the service twice in order to have the dmg file appear in finder - am I doing something wrong? Finally - are there any other alternate solutions - given diskimagemounter does NOT verify dmgs when opening in my MBA running Catalina.

I have downloaded a dmg file but when I click on it it keeps verifying.   I've also tried to go to /System/Library/CoreServices/Installer.app but I can't click on the .dmg because it is greyed out.  How can I open it?


We are running Symantec anti virus on Ubuntu 16.04, but now we've upgraded to Ubuntu 18.04 and Symantec doesn't support Ubuntu 18.04.  Is there any anti virus for Ubuntu 18.04 out there which can match Symantec-like anti virus support?   Thanks.

Are there any antivirus applications that work on Ubuntu 16.04? Thanks!


Martial arts is a monk skill where, if you are using a monk weapon, you can attack with that weapon and also make an unarmed strike as a bonus action.   Monk weapons are shortswords and simple melee weapons that don't have the heavy or two-handed properties. But if you use a quarterstaff (which is a simple melee weapon that doesn't have the two-handed property) with two hands, could you still make an unarmoured strike as a bonus action?

When using either the quarterstaff or spear as a Monk weapon, do you still gain the unarmed bonus action from Martial Arts if using 2 hands(1d8)?   On pg.78 of the PHB under Martial Arts it states that a Monk weapon cannot have the 2-handed or heavy property, so I assume since the versatile property is not the 2-handed property or heavy property then it does not matter if I use it in one or two hands. However, why then would a distinction be needed since the only simple weapon that does have the 2-handed property is a Greatclub, which is also mechanically identical to a quarterstaff used in two hands. Why make a rule that doesn't apply to anything?  The other interpretation is that you're meant to use 1d6 for damage in order to gain the Monk's Martial Arts bonus action, and using a 1d8 will forfeit the bonus because the quarterstaff is now considered 2-handed. Pg.147 under Versatile states "A damage value in parentheses (in this case 1d8) appears with the property—the damage when the weapon is used with two hands to make a melee attack."


I have a PHP/JSON as show below. JSON: {"posts_id_en":"101, 102, 103","posts_id_fr":"", "reports_id_en":"101, 102", "reports_id_fr":"101"}  PHP code: echo count(explode(",", $data->posts_id_en));    //  Line A  (3)  echo count(explode(",", $data->posts_id_fr));    // Line B   (1)  echo count(explode(",", $data->reports_id_en));    // Line C  (2)  echo count(explode(",", $data->reports_id_fr));    // Line D  (1)  Line A php code, Line C php code and Line D php code print 3, 2, and 1. Problem Statement: I am wondering what changes I need to make in the php code above at Line B so that it prints 0 as there are no elements inside posts_id_fr

PHP's explode function returns an array of strings split on some provided substring. It will return empty strings when there are leading, trailing, or consecutive delimiters, like this: var_dump(explode('/', '1/2//3/')); array(5) {   [0]=>   string(1) "1"   [1]=>   string(1) "2"   [2]=>   string(0) ""   [3]=>   string(1) "3"   [4]=>   string(0) "" }  Is there some different function or option or anything that would return everything except the empty strings? var_dump(different_explode('/', '1/2//3/')); array(3) {   [0]=>   string(1) "1"   [1]=>   string(1) "2"   [2]=>   string(1) "3" }


I was wondering which of the built in python libraries, support DTD validation.  I've been looking around and haven't been able to get a straight answer. I know ElementTree does NOT Support DTD validation.  Which ones do?

I need to validate an XML string (and not a file) against a DTD description file.   How can that be done in python?


In my code, I need it to take in a letter grade and then it will print out it's corresponding numeric value. The problem I'm having is I can't figure out how to get it to call the method correctly. I feel like I'm close but am confused as to what to do.   public class Grade {     public static void main( String[ ]  args)    {     Scanner input = new Scanner(System.in);     System.out.print("Enter a letter grade: ");     String letterGrade = input.nextLine();     Grade number = new Grade(letterGrade);     double grade = number.getNumericGrade();      System.out.println("The numberic value is: "                         + grade);      }   public double getNumericGrade(String letterGrade)     {         double numericGrade = 0.0;     if ((letterGrade == "A") || (letterGrade == "A+"))         numericGrade = 4.0;     else if (letterGrade == "A-")         numericGrade = 3.7;     else if (letterGrade == "B+")         numericGrade = 3.3;     else if (letterGrade == "B")         numericGrade = 3.0;     else if (letterGrade == "B-")         numericGrade = 2.7;     else if (letterGrade == "C+")         numericGrade = 2.3;     else if (letterGrade == "C")         numericGrade = 2.0;     else if (letterGrade == "C-")         numericGrade = 1.7;     else if (letterGrade == "D+")        numericGrade = 1.3;     else if (letterGrade == "D")         numericGrade = 1.0;     else if (letterGrade == "D-")         numericGrade = 0.7;     else if (letterGrade == "F")         numericGrade = 0.0;     else          numericGrade = -1;         return numericGrade;     }      }

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?


So i'm following a guide by blender guru and i'm following his exact steps. when he goes into the node editor it shows the nodes for the quick smoke. when i do it its just blank. help?

I have blender 2.69 and I've been following a tutorial on how to make text.  The only problem is when I go to add a glossy shader in the node editor it does not exist. Neither does the shader category.


I m trying to calculate the value of prefixCount in Trie, as below.  I am puzzled why the value of count is not returned as 3  Just in case , Tries contains [by,bye, byer, rat]. Why count is return as 0, and not 3.  public int prefixCount(String prefix) {     int count = 0;     TrieNode node = searchPrefix(prefix);     if(node != null)     {         prefixCount(prefix, node, count);     }     return count; }  public void prefixCount(String prefix, TrieNode node, int count) {     if(node.isEnd())     {         count++;     }      for(int index = 0;index < 26;index++)     {         char value = (char) (index + 'a');         TrieNode next = node.get(value);         if(next != null)         {             prefixCount(prefix + value, next, count);         }     } }   Am i doing something wrong while doing DFS operation.  Thanks !

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


I want to update only one Application like VLC or Firefox instead of upgrading all applications.  sudo apt-get upgrade   above command will update all the application, but I want only one particular application to be update.   Using Ubuntu 18.04 LTS on HP 15 R006TX Notebook PC.

How do I update a single package? As far as man apt-get says apt-get upgrade doesn't take a package/list of packages as parameter:     upgrade      upgrade is used to install the newest versions of all packages   currently installed on the system from the sources enumerated in   /etc/apt/sources.list. Packages currently installed with new   versions available are retrieved and upgraded; under no circumstances   are currently installed packages removed, or packages not already   installed retrieved and installed. New versions of currently installed   packages that cannot be upgraded without changing the install status   of another package will be left at their current version. An update   must be performed first so that apt-get knows that new versions of   packages are available.


If a main sequence star runs out of hydrogen fuel in the core, the core collapses because of its own gravity, but what exactly leads to the expansion of the outer layers of the star when it is becoming a red giant?

What causes the dimensions of a star increase when its hydrogen fuel is exhausted? For example, the Sun is expected to increase its radius 250 times. What causes this if its temperature is expected to fall? How gas can expand if the temperature falls?


I have this exercise:     Let $R$ be a Noetherian ring. Let $S\subseteq R$ be a multiplicatively closed set. Prove that $S^{-1}R$ is a Noetherian ring.   First off we claim that given a subset $I\subset R$, $$S^{-1}I \lhd S^{-1}R \quad \Rightarrow \quad I\lhd R\ \land \ I\ \cap S=\emptyset $$ That's true because $$ S^{-1}I \lhd S^{-1}R \quad \Rightarrow \quad (\ \frac {i_k} s \in S^{-1}I \Rightarrow \exists \ d_k\ \mathrm {maximal} :d_k|i_k,d_k\notin S)$$ So if we take the ideal in $S^{-1}R\ $generated by the elements $(\frac {d_1} 1,\frac {d_2} 1,\dots ,\frac {d_k} 1,\dots)$, clearly we obtain $S^{-1}I$, plus $I=(d_1,d_2,\dots,d_k,\dots)\lhd R$. Since every ideal on $R$ is finitely generated, it follows that ideals are finitely generated on $S^{-1}R$ too.  Is this correct? Do I need to be more exhaustive or am I wrong with something? Thank you :)

This is an unproven proposition I've come across in multiple places.   Suppose $A$ is a commutative Noetherian ring, and $S$ a multiplicative subset of $A$. Then $S^{-1}A$ is Noetherian.  Why is this? I thought about taking some chain of submodules $$ S^{-1}M_1\subset S^{-1}M_2\subset\cdots $$ and pulling back to a chain  $$ M_1\subset M_2\subset\cdots $$ of submodules of $A$ which must eventually stablize. Is there more to it than this? I kind of wary of assuming all submodules of $S^{-1}A$ have form $S^{-1}M$ for $M\leq A$.


I am new user to this forum and ubuntu as well. Have used windows only and I am not a coder or programmer, have a very limited knowledge.  My query refers to the error flag on my desktop. A day before Firefox & Tor browsers were running and my system hanged all of a sudden. I didn't think much about it and after a while I just closed it and later on power went off. Afterwards when I started my system, a red flag kind of mark appeared on my desktop at the top which mentioned about "....malformed entry 52 in list file" I have gone through  and tried applying it to resolve but the red flag didn't disappear which means it didn't help. I do not know what all other information will be required, hence kindly let me know. I am using Ubuntu 18.04.  PS: The error message mentioned to run 'Package Manager' but I have been unable to locate it. I appreciate all the help you are offering.  Below is the output obtained using "cat /etc/apt/sources.list"  # See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to # newer versions of the distribution. deb http://in.archive.ubuntu.com/ubuntu/ bionic main restricted # deb-src http://in.archive.ubuntu.com/ubuntu/ bionic main restricted  ## Major bug fix updates produced after the final release of the ## distribution. deb http://in.archive.ubuntu.com/ubuntu/ bionic-updates main restricted # deb-src http://in.archive.ubuntu.com/ubuntu/ bionic-updates main restricted  ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team. Also, please note that software in universe WILL NOT receive any ## review or updates from the Ubuntu security team. deb http://in.archive.ubuntu.com/ubuntu/ bionic universe # deb-src http://in.archive.ubuntu.com/ubuntu/ bionic universe deb http://in.archive.ubuntu.com/ubuntu/ bionic-updates universe # deb-src http://in.archive.ubuntu.com/ubuntu/ bionic-updates universe  ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu  ## team, and may not be under a free licence. Please satisfy yourself as to  ## your rights to use the software. Also, please note that software in  ## multiverse WILL NOT receive any review or updates from the Ubuntu ## security team. deb http://in.archive.ubuntu.com/ubuntu/ bionic multiverse # deb-src http://in.archive.ubuntu.com/ubuntu/ bionic multiverse deb http://in.archive.ubuntu.com/ubuntu/ bionic-updates multiverse # deb-src http://in.archive.ubuntu.com/ubuntu/ bionic-updates multiverse  ## N.B. software from this repository may not have been tested as ## extensively as that contained in the main release, although it includes ## newer versions of some applications which may provide useful features. ## Also, please note that software in backports WILL NOT receive any review ## or updates from the Ubuntu security team. deb http://in.archive.ubuntu.com/ubuntu/ bionic-backports main restricted universe multiverse # deb-src http://in.archive.ubuntu.com/ubuntu/ bionic-backports main restricted universe multiverse  ## Uncomment the following two lines to add software from Canonical's ## 'partner' repository. ## This software is not part of Ubuntu, but is offered by Canonical and the ## respective vendors as a service to Ubuntu users. deb http://archive.canonical.com/ubuntu bionic partner # deb-src http://archive.canonical.com/ubuntu bionic partner  deb http://security.ubuntu.com/ubuntu bionic-security main restricted # deb-src http://security.ubuntu.com/ubuntu bionic-security main restricted deb http://security.ubuntu.com/ubuntu bionic-security universe # deb-src http://security.ubuntu.com/ubuntu bionic-security universe deb http://security.ubuntu.com/ubuntu bionic-security multiverse # deb-src http://security.ubuntu.com/ubuntu bionic-security multiverse deb https://deb.torproject.org/torproject.org bionic main deb [arch=i386,amd64] https://deb.opera.com/opera-stable/stable non-free # deb-src [arch=i386,amd64] https://deb.opera.com/opera-stable/stable non-free   Update 1:  (A) screenprint of desktop to read the error message correctly   (B) screenprint from terminal, it is in two parts

I have unistalled and reinstalled the Ubuntu Software Center as per info I found in a similar thread and I got the same response about line 91 or something like that.  I just tried to upload a screen shot but since I'm new it won't allow me to.  I also can not figure out how to cut and paste anything so I have to hand type what the error screen says, both when I attempt to open the software center and nothing happens, when I try to enter commands into the terminal to uninstall, reinstall, whatever I get the same following:  COULD NOT INTITIALIZE THE PACKAGE INFORMATION An unresolvable problem occured while initializing the package information Please report t:his bug against the 'update-manager' package and include the following error message: 'E: Malformed line 91 in source list/etc/apt/sources.list (dist parse)  E: The list of sources could not be read.,  E: The package list of status file could not be parsed or opened.   How do I report bugs?  What can be done about this.  I have searched and everything everyone says to do leads me back to the same line error message.  So, I don't know how to get to line 91 in the source list; to tell you what it says. Sorry, I'm really new to this. That is what I need is to find out how to get there and fix what it says. I would really like to NOT have to re partition my hard drive and start from scratch, so I'm really looking forward to getting this problem solved. I need to be able to install new software.


$ bash date /bin/date: /bin/date: cannot execute binary file  $ bash -c date Thu Apr 14 19:27:08 EDT 2016   What does the error message of bash date mean? What does bash expect date to be?

Why does bash <command> fail to run?  $ bash date /bin/date: /bin/date: cannot execute binary file  $ /bin/date Fri Mar 18 05:59:24 EDT 2016  $ bash -c date Fri Mar 18 06:00:39 EDT 2016


I press F12 to render the camera view, but I just get a pixelish version of the render.    Can somebody tell me how to change that? I have already changed the object's "Render" Resolution to 100%.  Well, I have something to report now: When I use the middle mouse button to scroll out a little, the render appears a little smaller (seemingly at 100%), and it looks the way I expected. However, I wonder why that is that the render appears at like 125% for me instead of 100%.

When I hit F12 to render an image and zoom in it is quickly pixelated. How can I render a higher res display? I have looked through the settings and couldn't find a solution.


I'm trying to track total question counts on a few Stack Exchange sites via the API and it seems that a bulk of questions are deleted on Saturdays. The chart below shows daily question count on StackOverflow. On Saturdays, the total number of questions goes down by approx. 5000 questions. Which questions are being deleted? Is this new spam questions that accumulated over a week or is it old questions which beyond retention filter, e.g. no votes/no views/older than 5 years? Update 1 Here's the query that counts total number of old and unpopular questions: . On Thursday it was just over 4K for StackOverflow which matches the observed drops on Saturday.

At Sat, 30 Nov 2013 14:51:01 GMT, there was a sudden drop in the close votes review queue size from 98932 to 98314. This is about 600 questions over the course of one minute.  It doesn't seem like a routine cleanup script. If it was, this is a very odd time for it to run. Also, the drop occurred over the span of a minute, so it's highly unlikely there was simply increased review activity. So, I ask: What was its cause?         (yes please don't shoot me I know my freehand circle is blue) (it's actually a dark teal look again) (the source for this script I  (slightly modified), found through  post)  Raw data:  Epoch time  CV Size 1385822821  98932 1385822881  98932 1385822941  98932 1385823001  98932 *** 1385823061  98932 *** 1385823121  98314     [author's note: the difference between iterations is 60 seconds] 1385823181  98314 1385823241  98314 1385823301  98314 1385823361  98314


If I run a company for children, do I run    a children's company a children company  a childrens company   I originally thought "children's company" was correct but the children are not in possession of the company as the apostrophe would suggest.

I’ve been looking over what has been posted regarding the use of ’s.   I used to be a Technical Writer (years ago). The title of one of our training documents was Users’ Guide.  Once, a coworker said every time he saw that title he expected users to start coming.    Never made any sense to me, but I have to admit that the majority of us didn't understand the use of s’ in place of ’s.  What is the difference?


I have two dates in javascript:  var first = '2012-11-21'; var second = '2012-11-03';   i would like make:   if(first > second){    //...  }   how is the best way for this, without external library?

Can someone suggest a way to compare the values of two dates greater than, less than, and not in the past using JavaScript? The values will be coming from text boxes.


We know that the accident that causes the universes of Star Trek to diverge happend in the XXIII century. We also know that everything that happens after it (and so TOS, TNG, DS9 and VOY) is set in the new timeline. But what about Star Trek Enterprise, which is set in the XXII century? Is it also set within the new movie timeline? Is it canon within it?

The series "Enterprise" takes place a century before the events of TOS.  Are the things that happened in Enterprise considered canon or would they be a spin-off series of sorts? The specific events I'm speaking of are the temporal cold war, and the storyline of the Xindi wanting to destroy Humanity on behalf of the Sphere Builders.  Is anything that happened during Enterprise considered part of the Star Trek canon or have the creators of Star Trek chosen to pretend it never happened?


Lots of examples out there to do this temporary, but can I make this secondary IP address permanent, so that it survives reboots "the fedora way", or does this really need some kind of non-standard script to make this work? While this question (*) answers this partially, there a a lot of settings in the "ifcfg" scripts these days, like UUID, AUTOCONNECT_PRIORITY and a lot of IPV_6 settings, which i do not need at this point.  So the question is really how to add a secondary ip adress properly without screwing up network settings ? I am worried that I will introduce some weird network behaviour of the machine if i just "copy" these values.  e.g. what do do with these values of the default "eth0" (copy them,  change them?)  UUID=5e14c1d3-a58a-4540-8a9d-107210cc45aa AUTOCONNECT_PRIORITY=-999 IPV6_FAILURE_FATAL=no IPV6_ADDR_GEN_MODE=stable-privacy   (*)

I've always used the ifcfg-eth0:1 alias files to create additional addresses. However, in , it states that:     As the ip command of the iproute package now supports assigning multiple address to the same interface it is no longer necessary to use this method of binding multiple addresses to the same interface.    Furthermore, numerous answers and comments on this site mention that ifconfig is deprecated and that "ip" should be used instead.  I'm fine using it for live changes, but how do I persist the changes across reboots without using the alias files?


There's this third party software called Gabb. It's designed for a particular game. Basically, what it does, it runs multiple instances of that game at the same time, allowing me to play multiple accounts at once. I've read on many sources that it contains a virus that can leak out the game's account login info(username & password). I have the option to run it in a virtual machine where my unimportant accounts are. My question is, can the virus still leak out of that virtual machine and leak out my main account's login info?

If I am running a Windows 7 virtual machine on a Windows 7 host using VMWare or VirtualBox (or anything else) and the virtual machine is completely overloaded with viruses and other malicious software, should I worry about my host machine?  If I have an anti-virus program on host machine will it detect any problems?


last ... date      {                                 Sun Mar 31 12:00 date      |                                 Sun Mar 31 12:00 date      {                                 Sun Mar 31 00:00 date      |                                 Sun Mar 31 00:00 ...   Why are there e.x.: "{" in the last commands output? Some sort of script could do this? (on OpenBSD 5.1)

We recently set up a new FreeBSD 7.2 machine on March 11. When looking at last, we noticed some funny characters for the TTY field.   What do these characters mean? Note that at this time, the sysadmin was battling with NTP.  # last |grep date date             {                         Fri Mar 10 17:26 date             |                         Fri Mar 10 15:26 date             {                         Fri Mar 10 15:26 date             |                         Fri Mar 10 03:14 date             {                         Fri Mar 10 03:11 date             |                         Sat Mar 11 15:22 date             {                         Sat Mar 11 15:21 date             |                         Sat Mar 11 09:20   And according to man last, I can specify the tty using -t tty:  # last -t { date             {                         Fri Mar 10 17:26 date             {                         Fri Mar 10 15:26 date             {                         Fri Mar 10 03:11 date             {                         Sat Mar 11 15:21


Just started playing SC2. Never played RTS before. It's been 3 and a half weeks since I'm number 1 in my bronze league (40 games won/ 41 games lost)-680 points.   What I don't understand is why I'm not moved to the next league?(silver). I'm not good enough or is there a bug?

I've only played one placement match so far and I won it because my opponents were less than stellar.  I'm afraid that if I get similar placement matches in the future and end up winning them all I might get put into a league beyond my skill.  How many different leagues are there?  Once placed in a league, is there any way to move to a different one?  How?


Hello stackoverflow community,  How can I get the script name when using execfile() in IPython to run the script?  Demonstration:  I've created this script (named printScriptName.py)  import os,sys print os.path.basename(sys.argv[0])   This is the output when running it using IPython:  In [37]: execfile('printScriptName.py') ipython-script.py   Which is obviously not printScriptName.py.  Thanks.

I have scripts calling other script files but I need to get the filepath of the file that is currently running within the process.   For example, let's say I have three files. Using :   script_1.py calls script_2.py.  In turn, script_2.py calls script_3.py.    How can I get the file name and path of script_3.py, from code within script_3.py, without having to pass that information as arguments from script_2.py?  (Executing os.getcwd() returns the original starting script's filepath not the current file's.)


I found the following claim in :  Let $\mathfrak{g}$ be a Lie algebra, let $\mathfrak{h}$ be a Lie subalgebra of $\mathfrak{g}$ and let $I$ be a Lie ideal of $\mathfrak{g}$. Then the commutator space $[\mathfrak{h}, I]$ is again a Lie subalgebra of $\mathfrak{g}$.  I’ve been trying to prove this claim by showing that for all $x, x' \in \mathfrak{h}$ and $y, y' \in I$ the commutator $[[x,y],[x',y']]$ is again contained in $[\mathfrak{h}, I]$. For this I’ve tried to repeatedly use the Jacobi identity, but I’m only going around in circles.

Let $L$ be a Lie algebra over $A$, $I$ a Lie ideal in $L$, $K$ a subalgebra of $L$. The goal is to show that $[I,K]$ (the $A$-submodule generated by $[i,k]$ for $i \in I$ and $k \in K$) is a Lie subalgebra as well. If $$ S = \{ [i,k] : i \in I, k \in K\},$$ I believe that by bilinearity of the bracket it suffices to show that $[S,S] \subseteq [I,K]$. So take two elements $i, i' \in I$, $k, k' \in K$. The goal is to then show $$ [[i,k],[i',k']] \in [I,K].$$ This is where I'm lost and would like a hint as to where to go. My initial idea is to use the Jacobi identity to get $$ [[i,k],[i',k']] = -[i',[k',[i,k]]] - [k',[[i,k],i']].$$ Since $I$ is an ideal, $[i,k] \in I$, $[[i,k],i'] \in I$, and so $-[k',[[i,k],i']] \in [I,K]$. The idea then is to show that $-[i', [k',[i,k]]] \in [I,K]$. Use the Jacobi identity again to get $$-[k', [i,k]] = [i,[k,k']] + [k,[k',i]], $$ so that $$ -[i',[k',[i,k]]] = [i',[i,[k,k']]] + [i',[k,[k',i]]].$$ Trying the Jacobi identity again gets us $$[i',[i,[k,k']]] = -[i, [[k,k'],i']] - [[k,k'],[i',i]], $$ $$[i', [k,[k',i]]] = -[k,[[k',i],i']] - [[k',i],[i',k]].  $$ It seems like this is going nowhere. If $K$ was assumed to also be a Lie ideal, then this result follows easily (in fact, $[I,K]$ would be an ideal), but otherwise it doesn't seem like there's a way to rearrange things with just the Jacobi identity so that we get a linear combination of elements in $[I,K]$. I've alternatively thought about just approaching it at the level of showing $$ [[I,K],[I,K]] \subseteq [I,K].$$ Here, we use the Jacobi identity to note $$ [[I,K],[I,K]] \subseteq [[I,[I,K]],K] + [[K,[I,K]],I].$$ Now use the fact that $I$ is an ideal to get $$ [I,[I,K]] \subseteq I,$$ so we have $$ [[I,K],[I,K]] \subseteq [I,K] + [[K,[I,K]],I].$$ The goal here is to show $$[[K,[I,K]],I] \subseteq [I,K],$$ which seems to require $$ [K,[I,K]] \subseteq K.$$ If $$ [I,K] \subseteq N_L(K) = \{x \in L : [K,x] \subseteq K\},$$ then the result follows, but I don't see why this is necessarily true either.


[Edit] I rewrote the whole example as told by the comments.     float value = 0.52631580f;      float sum = 0;     for (int i = 0; i < 10; i++)     {         float division = sum / value;         int result = (int)division;          Console.WriteLine(division.ToString("0.00000") + " - " + result.ToString("0.00000"));         sum += value;     }  The results are not the ones expected: 0,00000 - 0,00000 1,00000 - 1,00000 2,00000 - 2,00000 3,00000 - 3,00000 4,00000 - 4,00000 5,00000 - 5,00000 6,00000 - 5,00000 <---- It should be 6 7,00000 - 7,00000  If I do it manually,  (int)6.00000000000f  <-- Returns 6, of course. How is that possible?

Consider the following code:   0.1 + 0.2 == 0.3  ->  false   0.1 + 0.2         ->  0.30000000000000004   Why do these inaccuracies happen?


On the per-site-metas, users don't have a reputation score different from their score on the site (so a user's meta.stackoverflow reputation is just their Stack Overflow reputation). But meta.stackexchange has no base site, so it just has its own reputation score. But why?  The recurring theme on meta is that votes on meta mean different things. Most relevantly, feature request voting is completely different:     On posts tagged feature-request, voting indicates agreement or disagreement with the proposed change rather than just the quality or usefulness of the post itself.   Reputation by its very nature is using gamification to create incentives. On most of the sites this incentive is clear: have users contribute quality content. On meta, it's less clear. A user who submits an unpopular feature request on meta gets the double frustration of having their request denied and losing a bunch of reputation in the process. Additionally, given how the site-specific-metas work in terms of reputation, I'm left wondering whether meta was ever supposed to have reputation in the first place.  So what is the intended incentive of reputation on meta? Is discouraging users from submitting unpopular feature requests by design or an oversight?  Note: This question is not about functionality. I understand that privileges are unlocked with reputation, but that could easily be done via a Stack Exchange-wide reputation rather than a meta-specific one. This question is just about the incentives that reputation on meta creates.

I realize I am taking a risk by reopening what seems to be an old, hoary, and thorny discussion. However, it seems that in all the long discussions about Meta Stack Exchange reputation, what it means, and why it's separate from reputation on other sites, I have never seen a complete answer to this question:  If reputation on Meta Stack Exchange is used by the community to indicate agreement with an opinion instead of the quality of a post, why is it still tied to site privileges?  The association between reputation and privileges makes sense on other Stack Exchange sites, where reputation is a measure of your participation in the site and the quality of your questions and answers. If you contribute positively to the community your reward is increased privileges, whereas your punishment for "polluting" the site with bad questions or unhelpful answers is a loss of privileges.  However, on Meta Stack Exchange, reputation is a measure of the popularity, not the quality, of your contributions. Tying reputation to privileges means that losing privileges on the site is a punishment for expressing an unpopular opinion, and gaining them is a reward for agreeing with the majority.   My opinion:  I don't think that tying privileges to popularity makes sense as a feedback system. It doesn't really encourage quality contributions, and even worse, acts to suppress minority opinions through the threat of losing privileges. As a user with fairly low reputation, I am afraid of asking a question that may be controversial, because if enough other members disagree with me I will be stripped of the ability to vote and chat. Even if I had higher reputation, I would still be concerned that expressing a controversial opinion would cause me to lose helpful privileges like editing and viewing close votes.   The FAQ tells new users "not to be concerned" by downvotes because all it means is that the community disagrees with them. However, I think new users have every right to be concerned about downvotes, because they still mean the loss of privileges.


Can anyone provide me with an example of a non-trivial group $G$ which is isomorphic to $G\times G$. What is the mapping $G \to G\times G$?

I was trying to find an example such that $G \cong G \times G$, but I am not getting anywhere. Obviously no finite group satisfies it. What is such group?


deals with getting a list. So I get this:  $ psql --list                                     List of databases       Name      |  Owner   | Encoding |   Collate   |    Ctype    |   Access privileges ----------------+----------+----------+-------------+-------------+-----------------------  testdb1        | postgres | UTF8     | en_US.UTF-8 | en_US.UTF-8 |  odoo           | openerp  | UTF8     | en_US.UTF-8 | en_US.UTF-8 |  odoo-demo      | openerp  | UTF8     | en_US.UTF-8 | en_US.UTF-8 |  odoo8          | openerp  | UTF8     | en_US.UTF-8 | en_US.UTF-8 |   I could use psql --list|grep UTF8|awk '{ print $1 }' to get a list of just the databases. Can psql also give me a clean useful list directly?

I want to use psql to list all of the databases on a Postgres server, to be parsed by a script. This command lists them:  psql -l -A -t   but the output shows an obvious issue: the records are separated by newlines, but also contain newlines.  $ psql -l -A -t postgres|postgres|UTF8|en_CA.UTF-8|en_CA.UTF-8| template0|postgres|UTF8|en_CA.UTF-8|en_CA.UTF-8|=c/postgres postgres=CTc/postgres template1|postgres|UTF8|en_CA.UTF-8|en_CA.UTF-8|=c/postgres postgres=CTc/postgres   Using the -R option I can change the record separator, but it seems like no matter what I change it to, there's the risk of that string appearing in the data. Is it possible to instead tell psql to replace the newlines in the data with something else? (and then what if that string also appears in the data?)  I'd also tried to set the record separator to a null character with such sequences as -R '\000' and -R "\0", but it doesn't seem to interpret escape sequences in the parameter at all, and just uses the literal string \000 instead.  The other option I know of to list all databases is:  psql --quiet --no-align --tuples-only --dbname=postgres --username=postgres --host=127.0.0.1 --port=5432 --command="SELECT datname FROM pg_database"   but that requires me to give the password for the postgres user, so it's not desirable. Perhaps there's another way to get a list of the names of all databases?


I want to make Bootable USB device to install windows 8 on my pc. Please suggest most easiest way to this.  Any software available to that?

Possible Duplicate:          How do I make a bootable USB with Windows 8? I would like to install it on my device with a broken DVD device. Has anyone faced this situation?


Is it possible to purchase a pre-paid SIM card that with cellular Internet access in Iceland ? If so, in what parts of Iceland can I expect coverage ?

Next month I am traveling to country X, where I would need Y minutes of calls, Z text messages and most importantly Q megabytes of data. How can I find the cheapest/most reliable SIM card for my needs?


The corrupting effects of the One Ring on the hobbit Sméagol are well-known: when his relative Déagol found the Ring, Sméagol became instantly affected by its influence and strangled Déagol when he refused to hand over the Ring. The One Ring changed Sméagol into a grotesque creature that lived in the darkness and shadows of goblin tunnels and caves; and fed on stray goblins / fishes or basically whatever squiggly stuff that could be found. The ring also gave him unnaturally long life span and a personality like a crazy road lizard.  But how did Sméagol's name become Gollum? Why did people start to address him as Gollum? Was the name an inherent alter-ego that came with the ring? Did someone name him Gollum?

I don't recall any of the characters in Lord of the Rings or The Hobbit calling Sméagol Gollum in his face. It seems to be more of a private epithet. Is this correct? Does Gollum know that others call him Gollum?


I am using this to convert text to hash.  How should I convert the hash text to its original. It is needed to display the text.  C#:  private string HashPassword(string sText) { Byte[] data = System.Text.Encoding.UTF8.GetBytes(sText); Byte[] hash = new System.Security.Cryptography.SHA256CryptoServiceProvider().                ComputeHash(data); return Convert.ToBase64String(hash); }

The current top-voted to  states:     Another one that's not so much a security issue, although it is security-related, is complete and abject failure to grok the difference between hashing a password and encrypting it. Most commonly found in code where the programmer is trying to provide unsafe "Remind me of my password" functionality.   What exactly is this difference? I was always under the impression that hashing was a form of encryption. What is the unsafe functionality the poster is referring to?


I have 2 Monitors and want to observe on one monitor 1st sheet and on the other monitor 2nd sheet but no matter how many excel files I open they are all on one monitor.  Can I split them to two screens?  I have Excel 2007 and working on 2003 file. Thanks a lot for your time!

I have to do work between two spreadsheets and I need to view them side by side. I can't just open the workbooks in separate instances because I need to make use of features like paste formatting, and all of that goes away when the workbooks aren't in the same instance.  Is there anything I can do to get two windows open, each with a separate workbook, each maximized on a different monitor, and still have access to the advanced cut/paste features?


I own a Samsung galaxy scl i9003 and I would like to port Ubuntu touch on this device. We don't have an official cyanogenmod, but we have an unofficial version of it. I did the built of the unofficial cyanogenmod 10.1 but now I don't know how to proceed, and from where start following the porting guide to create a Ubuntu touch build flashable to my device.  Please, I hope someone could help me  Thanks in advance

I have a Samsung Galaxy S Plus i9001 and I would like to install Ubuntu Touch on it, but my device is not officially supported by cyanogenmod. Anyway a port exists and also some derived roms (like ehndroix). If exists, what is the path to create a working ubuntu-touch build for my device? Thank you in advance.


[Edit] Note that this is not a duplicate question. The law was changed on the 1st of April 2016:     Additionally, from 1 April 2016, all travellers wishing to enter the US under the VWP will need to hold a passport with an integrated chip (an ePassport).   I have an ePassport, but I'm not sure if the chip in it still works as the automated check in machines by Aer Lingus at Dublin Airport were unable to read my passport. The automated passport machines on arrival at Dusseldorf Airport seemed to work (although I have no idea if those machines literally just take a visual scan of the passport or read the (possibly broken) chip in my passport).   Just in case the chip in my passport is indeed broken, what would happen at a US port of entry under the new rules effective from April 1st 2016?   Would I be denied entry or just scrutinized more?  Is there a way to check if the chip still works?

My biometric passport inadvertently spent some time under the rain. It's not badly damaged but some sheets are a bit deformed and there are tiny brown spots on the side. I am wondering if there is an easy way for me to determine if the chip is still working. If it does not, can I still use the passport? Which countries require a biometric passport or actually use the data?  Also, how much of a problem can a lightly damaged/worn out passport be? Is it more likely to be an issue in some countries than others?  PS: Right now, I am preparing for a possible trip to the US and since there is still time, I will most likely ask for a (costly, turned out requesting a new one was free, for some reason) new passport just in case but I would be curious to know if that's really necessary or about potential issues in other countries as well. The passport in question is still valid for more than three years, still has many free pages and was issued by a EU country whose citizens are eligible for the visa waiver program.


After some apt upgrades my Wayland session seems broken, the mouse moves but I can't click on anything. I want to try if X.Org works, but as the UI is broken, I must change the session type in the text console.  How do I configure X.Org to start instead of Wayland when the desktop UI is unusable, in the text console?  I got a workaround by using the keyboard: type win, log out and change focus with TAB. From there I could switch to X.Org using keyboard.

Some of my applications don't work on Ubuntu 17.10 Wayland. How can I switch back to Xorg?


In OSX 10.10 there was an option to go to Finder > Empty Trash or Finder > Secure Empty Trash  In OSX 10.11 there now only seems to be an option for Finder > Empty Trash  Any ideas way i can get it back ?

There used to be an option to delete files securely in older versions of Mac OS X. However, I am unable to find the same in macOS High Sierra 10.13.5.  Is the option removed? If yes, what's the probable reason? As I understand, the command was useful to ensure that data could no longer be recovered from the hard drive.  I am using a Late 2013 15" retina MacBook Pro.


Basic Programming Concepts  Lab # 9 – Arrays Write a cinema reservation program to allow customer to reserve cinema seating. At the beginning of the program, ask the customer to input the name and display customize greeting message. Once the seat is reserved, it should be marked as ‘**’. If customer chooses a seat that has been reserved by other customer, display a message to inform customer and suggest the next available seat.  Sample output:  Hi, what is your name? Amy  Welcome, Amy!    CINEMA 1 SEATING PLAN    00  01  02  03  04 05  06  07  08  09 10  11  12  13  14 15  16  17  18  19 20  21  22  23  24 25  26  27  28  29 Which seat do you want? 21  Would you like to make another booking?(Y or N)  If seat chosen has been reserved by others, advice next available seat.  Now for the code. The problem with the code is because I probably don't know how to change someone's "y" into a "true" for boolean. Why can't coding ever be easy?  import java.util.*;  public class cinema {  public static void main(String args[]) {     Scanner input = new Scanner(System.in);      int booking;     String name;     int suggestion = 0;     boolean check1 = true;     String check2 = "_";     String check11 = "_";      //create array     final int ARRAY_LENGTH = 30;     int[] array = new int[ARRAY_LENGTH];      String[] seats = { "00", "01" , "02" , "03" , "04" , "05" , "06" , "07" , "08" , "09" , "10"                          , "11" , "12" , "13" , "14" , "15" , "16" , "17" , "18" , "19" , "20" , "21"                           , "22" , "23" , "24" , "25" , "26" , "27" , "28" , "29"};      System.out.println("Hi, what is your name?");     name = input.nextLine();      System.out.printf("Welcome,%s!\n",name);      System.out.println("*********************");     System.out.println("CINEMA 1 SEATING PLAN");     System.out.println("*********************");      do{      for(int a = 0; a < 30; a++ ){     System.out.printf("%s\t", seats[a]);     if (a % 5 == 4){     System.out.printf("\n");     }     }     System.out.println("Which seat do you want?");     booking = input.nextInt();      if(seats[booking] == "**"){         System.out.println("Sorry! Seat taken.");         for(int b = 0; b < 30; b++){             if(seats[booking + b] == "**"){                 check2 = seats[booking + b];             }             else if(seats[booking - b] == "**"){                 check2 = seats[booking - b];             }             else{             }         }//end for loop         System.out.printf("Suggest to take seat:%s\n", check2);     }//end if      seats[booking] = "**";      System.out.println("Would you like to make another booking?(Y or N)");     check11 = input.nextLine();      while(check11 == "y"||check11 == "n"){     if(check11 == "y"){         check1 = true;         System.out.print("a");     }     else if(check11 == "n"){         check1 = false;         System.out.print("b");     }     else{     System.out.println("Would you like to make another booking?(Y or N)");     check11 = input.nextLine();     }     }//end while       }while(check1);//outer while   } //end main }   Please don't flag it as a duplicate. The problem in it is different. I can't get the   "Would you like to make another booking?(Y or N)"  to work. When I meant I couldn't get it to work, I meant that the program wouldn't let me have the opportunity to enter y or n. The true problem is the check11 = input.nextLine();. Anyone can tell me what's wrong with it?  Also, the previous reference really didn't help. I didn't understand how it refers to my quetion.

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 running 18.04LTS but I cannot upgrade to 20.04LTS using either the updater or the command line.

I'm following the , but on launching the upgrade tool I get this response:  Checking for a new ubuntu release No new release found   Am I doing something wrong? Is there a workaround?


I'm having a hard time proving that $R_2$ with the standard topology is normal. I started off by trying to show that for any two disjoint closed sets, A and B, we could find balls (so since we're in $R_2$ open sets) around them, U and V, but I don't know how to guarantee that these two balls are disjoint from each other. Any hints would be appreciated!

I've seen this proof of the fact that a metric space is normal multiple times but I can't understand how it's valid. Notation used: For $x \in X$, and $Y$ a subset of $X$, define $D(x,Y)=\inf \{d(x, y): y \in Y\}$. The above proof uses that if $Y$ is a closed set, then $D(x, Y)>0$, $\forall x \in X \setminus Y $ and this in turn implies $\space D(x, Y)> \epsilon$, $\forall x \in X \setminus Y $ for some $\epsilon > 0$. If the above proof was true, then we could also argue that for any $y \in Y$ we have $B(y, \frac{\epsilon}{3}) \subseteq Y$ (since $d(y, x)> \epsilon, \space \forall x \in X \setminus Y \Rightarrow B(y, \frac{\epsilon}{3}) \cap \{X \setminus Y\} = \emptyset) $ so $Y$ is open which is obviously false. I don't know what I'm missing becuase this kind of proof seems to appear everywhere. Thank you!


What is the purpose of having different auxiliary verbs ("is", "are", "am") for different pronouns ("He", "You", "I"...) instead of simply using "is" for all pronouns? It seems like the pronoun always exists in a sentences where the auxiliary verb that relates to it appears, so, to me, having different auxiliary verbs seems to serve the sole purpose of overcomplicating the language and making it more difficult to learn.

In many languages, including English, the most important verbs are irregular. Examples include:   to be  to do  to get  to go  to have  to make   The same applies (roughly) to many other languages I know about (Dutch, German, French, Spanish, Swedish) and presumably to many other languages too.  Is there any reason why these everyday verbs tend to be irregular?


I will soon get my first paper submitted. Because my name is very common I think it will be hard to look for my papers in databases in the long term. If I want to decide on a pseudonym (author name different than my real name) it must be now before my first paper. I wonder about choosing a pseudonym that is a small variation from my own name so that it is unique in databases. Like changing my first name spelling (John -> Jon) or adding middle name or changing my last name (Smith -> Smyth). Is it a good idea or am I overthinking it? Will it be a problem later?

For a similar thing, , where Jay Wacker managed to get people to call him by the name Jay even though he didn't need to get a legal name change. I'm not sure how to go about this though.  The main problem with me is that I have such a frustratingly common name that a lot of people cannot find me when they google me. So many of them simply don't notice the middle initial that I always use in between my first and last names, and this could actually become a major issue in academia, since people have little time and are prone to giving up quickly if they want to look for me (or for my papers) and can't find me at all (I know this having seen how several academics use the Internet and how they look for people's names). This, in turn, could easily ruin my citation count in the future (it's not just that - it's helpful to others when I have a less common name so that they can more easily locate my stuff). I already know at least several people who specifically told me that they tried to find my email but that they couldn't find it (and this isn't limited to just them - there are many, many more - including long-lost friends who have wanted to talk to me for a long time, but who couldn't find me due to said ultra-common name). Of course, people can go through the respective university directories, but how many people really do that? From my observations (when I've seen people look for someone else), very very few do it. Hell, there are even several people at my OWN university who share the same exact first+last name as me.  In Academia, this is even a bigger problem because the vast majority of your connections will be people who only vaguely recognize/know you, so they may know most of the search clues. Even a "full name" + university won't solve all the problems, because I may switch universities and people may only remember the old university that I was in. I'm also very very interdisciplinary, so I want to be searchable to people outside my field as well.  And even if I fix the issue for Google with a massive SEO operation or whatever (that may even be impossible for my ridiculously common name), it's still not going to fix the problem for all of the other ways that people use search.  I'm currently transitioning between undergrad and grad school, so now may be the perfect time for a name change? But I don't know what to do. Is it better for me to change my first name or my last name? The problem is that a citation like "Chen 2011" is going to produce so many entries that no one will ever find them, even though they frequently do google things like that (and I simply cannot prevent people from googling something like that). Chen is so frustratingly common that even a "Chen and Name2 2011" paper could come from some random medical paper rather than from something I wrote.  As an additional complication, the % of Chinese people using the English Internet is exponentially rising, and I can only expect the problem to get worse in the future because of that (and not just for my first name, but even variants of my first name too).


So I've been accepted into a masters program and there is this professor that I really want to get involved with hopefully as a research assistant. And since many if not most researches are being conducted online, I was wondering if its a good idea to email the professor to see if there is any way I can get exposure to his research by either working as his assistant or intern. I'd appreciate any comments!!

When needing to ask a professor about something important and potentially delicate, what is an appropriate way to phrase the question or write the email?  Examples include:   Requesting a recommendation letter Asking for exceptions to policy (e.g., ignoring a course prerequisite, rescheduling an exam) Asking if you can do research with them, join a group, get into a program Scheduling a meeting, exam, or defense Letting them know about a change of plans Letting them know about a life event affecting your work or studies (e.g., wedding, funeral, sickness, vacation)


Let $X$ be a set. Define the following notion of convergence on the power set $P(X)$: A sequence of sets $(A_i)_{i\in \mathbb{N}}$ is convergent if and only if the limsup and the liminf of the sequence are equal. Is there a topology $T$ on $P(X)$ such that $(A_i)_{i\in \mathbb{N}}$ converges if and only if $(A_i)_{i\in \mathbb{N}}$ converges with respect to $T$? Background: Recall that the power set of $X$ is the set of all subsets of $X$. If $\{A_i\}_{i\in \mathbb{N}}$  is a sequence of points in $P(X)$, the liminf of $\{A_i\}$ is the set of points in all but finitely many $A_i$, and the limsup of $\{A_i\}$ is the set of points in infinitely many $A_i$. The notion of convergence if and only if the limsup equals the liminf behaves in many ways that suggest it is topological. For example, a nested increasing sequence of sets $A_1 \subseteq A_2 \subseteq \ldots$ converges to its union, a nested decreasing sequence $A_1 \supseteq A_2 \supseteq \ldots$ converges to its intersection, if two sequences agree on all but finitely many points then one converges iff the other converges. However, this is not sufficient to guarantee that it is indeed topological. For example, there is no topology on the space of functions from $\mathbb{R}$ to $\mathbb{R}$ that is equivelent to convergence pointwise almost everywhere with respect to Lebesgue measure.

Given a sequence of sets, is there some well-defined notion of a limit of a set?   In other words, given some universe set $U$, I am wondering if there is a topology on $2^U$ (the powerset of $U$) such that the usual intersection and the union limits converge in that topology.  As an explicit example, let $U=\mathbb{N}$,  $S_n = \{x\in \mathbb{N} | n< x \le 2n \}$,   $T_n = \{n\}$.  The limit of both sequences above should be the empty set by the following argument:  \begin{align} S_n &\subset (n,\infty) \\\\ \lim_{n\to\infty} S_n &\subset \lim_{n\to\infty} (n,\infty) = \cap_{n\in\mathbb{N}} (n,\infty) = \emptyset  \end{align}  (I'm not sure how to justify passing a set inclusion to the limit.)


As an example, for any one dimensional real valued function $f$, if $q<k$ then $\prod_{i=k}^q f(i)=1$. I thought it was $0$ and that was breaking my intuition about some formulas I'm working with. This makes much more sense. Why is this true? Has the fact that the zeroth power of any real number equals one has anything to do with this?

For example $\prod_{2 \le j  < 1} 2^j= 1.$ How does that happen?


Terminal.app does some very odd color shifting that makes it impossible to match colors consistently, and I'm wondering if there is any way to disable it or better control it. The "magic" is what shows purple instead of blue, for example, even when the ansi color for the theme is set to plain blue.  This behavior appears to be tied to setting the background color... setting any background color (with terminfo setab capability) disables the "magic" color shift, while an attribute reset (sgr0) re-enables it.  This is my test (sets the foreground, prints some unicode filled blocks, explicitly sets the background to black, prints again):  b=$'\xE2\x96\x88' && bs=$b$b$b$b$b$b$b$b &&   tput setaf 4 && echo -n "$bs" &&   tput setab 0 && echo "$bs"   With the default theme, it prints purple (magic) then blue (ansi). So, my first attempt was to sample the purple color, and update the preferences to use that purple instead of blue... everything should be consistent now, right?  On the next run, I get a slightly brighter purple and then the purple I entered. At first I thought I just put the color in wrong, but as I kept brightening the color setting to match what Terminal.app was showing without the background set explicitly, the Terminal.app just kept getting brighter too -- all the way up until it was white!  From this, it seems to me that Terminal.app is automatically scaling the the colors displayed on the default background color by some factor, but it leaves colors on any explicitly set background alone; making it impossible for the two colors ever to match (except white and black).  FWIW, the window background is set to fully-opaque black.  Is there any way to get rid of this behavior? I'm thinking that this is maybe bug-report-worthy, but I'm curious if there is just something I'm missing.

While it's great that Terminal now has built-in support for changing the ANSI colors, I find it annoying that it automatically adjusts the colors to improve contrast, which means the colors that I actually pick often end up washed out or off in some other way. Here's a screenshot explaining the problem:     This bugs me because I like to use the same color scheme in Terminal and MacVim, and with this handling of colors by Terminal, they don't match up to the ones in MacVim.  Does anyone know of a solution to this, besides switching to iTerm 2 (which I'd rather not – I like the rest of Terminal, especially some GUI touches like the pulsating visual bell). Thanks!