If Quicksilver runs at speeds faster than the speed of sound then how come the song he's listening to on headphones is playing at a normal rate?
In Days Of Future Past, Quicksilver spends a lot of time playing with electronics.  In his famous tour de force scene in the Pentagon, he specifically puts his headphones on before running around the kitchen.  But why?  Does the music on his Walkman speed up with him as he uses it, or is it still operating at "normal" speed? Or indeed, does any electronic device that he touches speed up?
$f^2$ and $f^3$ are holomorphic implies $f$ is holomorphic. What are tag synonyms and merged tags? How do they work? After discussion with colleagues regarding the use of the 'var' keyword in C# 3 I wondered what people's opinions were on the appropriate uses of type inference via var?  For example I rather lazily used var in questionable circumstances, e.g.:-  foreach(var item in someList) { // ... } // Type of 'item' not clear. var something = someObject.SomeProperty; // Type of 'something' not clear. var something = someMethod(); // Type of 'something' not clear.   More legitimate uses of var are as follows:-  var l = new List&lt;string&gt;(); // Obvious what l will be. var s = new SomeClass(); // Obvious what s will be.   Interestingly LINQ seems to be a bit of a grey area, e.g.:-  var results = from r in dataContext.SomeTable               select r; // Not *entirely clear* what results will be here.   It's clear what results will be in that it will be a type which implements IEnumerable, however it isn't entirely obvious in the same way a var declaring a new object is.  It's even worse when it comes to LINQ to objects, e.g.:-  var results = from item in someList               where item != 3               select item;   This is no better than the equivilent foreach(var item in someList) { // ... } equivilent.  There is a real concern about type safety here - for example if we were to place the results of that query into an overloaded method that accepted IEnumerable&lt;int&gt; and IEnumerable&lt;double&gt; the caller might inadvertently pass in the wrong type.  var does maintain strong typing but the question is really whether it's dangerous for the type to not be immediately apparent on definition, something which is magnified when overloads mean compiler errors might not be issued when you unintentionally pass the wrong type to a method. I often see statements in discussions about web displayed image quality that go something like this: "I only upload pictures at 72 dpi and 1200 pixels on the long edge, so if someone copies and prints the image it won't look as good as if it were 300 dpi."  What? Have I missed something here?  Does an image edited and saved/exported with 1200x800 pixels at 300 ppi look any different online than the same image saved/exported with 1200x800 pixels at 72 ppi? Other than the metadata regarding ppi, is there any difference in the two images at all? If so, what is the difference? If I tell my printer to print the images at 4R (4X6 inches) will there be any difference at all in how the printer creates a print from the 1200x800 @ 300 dpi image versus the 1200x800 @ 72 dpi image? It's taken me almost 10 years of Linux usage to ask this question. It was all trial and error and random late-night internet surfing.  But people shouldn't need 10 years for this. If I were just starting out with Linux, I'd want to know: When to alias, when to script, and when to write a function?  Where aliases are concerned, I use aliases for very simple operations that don't take arguments.   alias houston='cd /home/username/.scripts/'   That seems obvious. But some people do this:  alias command="bash bashscriptname"   (and add it to the .bashrc file)   Is there a good reason to do that? I'm trying really hard, but I genuinely can't think of any circumstances in which I'd want to do that. So, if there is an edge case where that would make a difference, please answer below.  Because that's where I would just put something in my PATH and chmod +x it, which is another thing that came after years of Linux trial-and-error.  Which brings me to the next topic. For instance, I added a hidden folder (.scripts/) in the home directory to my PATH by just adding a line to my .bashrc (PATH=$PATH:/home/username/.scripts/), so anything executable in there automagically autocompletes.  If I needed to.  I don't really need that, though, do I? I would only use that for languages that are not the shell, like Python.  If it's the shell, I can just write a function inside the very same .bashrc:  funcname () {   somecommand -someARGS "$@" }   As I stated, I found a lot of this out through trial and error. And I only truly saw the beauty of functions when my computer died and I was forced to use the computers of the people around me when they weren't using them.   Instead of moving a whole directory of scripts from computer to computer, I ended up just replacing everyone else's .bashrc with my own, since they had never even made a single modification.  But did I miss anything?   So, what would you tell a beginning Linux user about when to alias, when to script, and when to write a function?   If it's not obvious, I'm assuming the people who answer this will make use of all three options. If you only use aliases, or only use scripts, or only use functions—or if you only use aliases and scripts or aliases and functions or scripts and functions—this question isn't really aimed at you. PostgreSQL execute a default query when no row are returned I need to calculate the average score of a list of userId.  I have a table user_place_score:  (user_id, place_id, score)   Sometimes I do not have the score (no row for (user_id,place_id) in the table) so I need to fetch a "default" score from the table default_place_score:  (place_id, score)   Is is possible in PostgreSQL to do this in one query? For a given list of users and one place_id, select all their scores in the user_place_score and if no row is found then take the score found if the default_place_score table?  Basically I want to avoid doing this kind of stuff:  for (Integer userId : userIds) {   score = (query to fetch the score for this userId)   if (score == null)     defaultScore = (query to fetch the default score for this PlaceId)    total = total + defaultScore }  //return the average return total/numberOfUser What are the rations Rey eats? In The Force Awakens, we see Rey pouring some flour-like polystarch rations into water so that the flour amazingly transforms into something that looks like bread. What are these rations? Is there any documentation of the fictional chemistry and biology that makes the starch rations behave as they do? Why is "chmod -R 777 /" destructive? This is a  about File Permission and Why 777 is "destructive".   I'm not asking how to fix this problem, as there are a ton of references of that already on Server Fault (reinstall OS). Why does it do anything destructive at all?  If you've ever ran this command you pretty much immediately destroy your operating system. I'm not clear why removing restrictions has any impact on existing processes. For example, if I don't have read access to something and after a quick mistype in the terminal suddenly I now have access well... why does that cause Linux to break? I would like to clarify something that I don't think is clear in   The first automatic delete rule kicks in at 9 days for closed questions:     If the question was closed more than 9 days ago, and ...         was not closed as a duplicate   has a score of 0 or less   has no answers with a score > 0   some other criteria that don't matter right now...      Then, at 30 days, there's:     If the question is more than 30 days old, and ...         has −1 or lower score   has no answers   is not locked      This rule applies to both open and closed questions, but it doesn't mention the same exemption for duplicates.  I'm pretty sure that I've seen old, downvoted duplicates disappear on ServerFault (and that fits what the rule says), but I'm also sure I've seen lots of comments along the lines of  "duplicates aren't deleted."  So what I'm after is a clear statement from a power-that-be or a clear reference that says "duplicate questions fall under the same 30-day automatic deletion rule as any other question."  (or that they don't)  (Note: I realize this doesn't apply the stub left behind when a question is merged into another.  Those "stubs" are locked and are never deleted.) How do get my sitelinks to appear on Google search results? Nested regression model Giving edit reputation bonus for same user for same post multiple times On Stack Overflow, I saw some users editing the same question multiple times, and getting the 2 point reputation bonus for each time.  I saw it during review of a suggested edit (some months ago, I forgot the question that's why I'm unable to paste the link here). I rejected it and gave the reason in the "Other" reason field.  Most of the time I saw that users first formats the code, and then after approval they edit the title and fix the grammar.  Why is this allowed?  My point is, if an user gained 2 reputation points for a particular edit, then why give another 2 points again for the same post? Because the second edit on same question/answer means that there were some mistakes or misses in their previous edit. What is the best way to randomize an array of strings with .NET? My array contains about 500 strings and I'd like to create a new Array with the same strings but in a random order.  Please include a C# example in your answer. How do I set a static IP address in Windows? Word for the opposite of "hypochondriasis" Why is filling a balloon from your mouth much harder initially? Why is it that when you first fill up a balloon, it's hard to get air through, but after inflating it a bit, it becomes much easier to further inflate the balloon? How to partially hide content in beamer latex? Converting PostGIS point to text causing loss of data? I have a road network and want to test connectivity between the features.  I am having trouble with two specific features, the rest of the dataset is functioning just fine.  When I get those 2 links' start &amp; end locations using ST_StartPoint and ST_EndPoint, the result is that they are slightly different.  However, when I convert the result to text by wrapping it like so:  ST_AsText(ST_StartPoint(geom)) and ST_AsText(ST_EndPoint(geom))  then the results are exactly the same.  Is it possible they are actually off by a tiny amount like .000000001 and the ST_AsText loses a decimal point? 'pyrcc5' is not recognized as an internal or external command I installed QGIS 3.0 on Windows 10. I get this error everytime i run the pyrcc4 or pyrcc5 command:  'pyrcc4' is not recognized as an internal or external command  Even if I find a place with a pyrcc4.exe file or a place with apyrcc5.bat file and add the path to the environment variables I get the same error. In the previous installation of osgeo4w i had a pyqtdev folder or something similar appear I think it was on C/. Was there supposed to be such a folder, do I need to download pyqt separately? Retrieving n rows per group I often need to select a number of rows from each group in a result set.  For example, I might want to list the 'n' highest or lowest recent order values per customer.  In more complex cases, the number of rows to list might vary per group (defined by an attribute of the grouping/parent record). This part is definitely optional/for extra credit and not intended to dissuade people from answering.  What are the main options for solving these types of problems in SQL Server 2005 and later? What are the main advantages and disadvantages of each method?  AdventureWorks examples (for clarity, optional)   List the five most recent recent transaction dates and IDs from the TransactionHistory table, for each product that starts with a letter from M to R inclusive. Same again, but with n history lines per product, where n is five times the DaysToManufacture Product attribute. Same, for the special case where exactly one history line per product is required (the single most recent entry by TransactionDate, tie-break on TransactionID.