I am wondering if it makes a difference if you pass an immutable type into a method in constrast to passing an mutable type into a method. I'm asking this because of the following code:   I have the following two methods, one taking a String (immutable) parameter and the other taking a StringBuilder (mutable) parameter:  static void change(String s) {     s = "!!!"; }  static void change(StringBuilder sb) {     sb.append("!!!"); }   Code for executing the code (with results written as comments):  public static void main(String[] args) {     String s = "Hello";     change(s);     System.out.println(s); //Prints Hello      StringBuilder sb = new StringBuilder("Hello");     change(sb);     System.out.println(sb); //Prints Hello!!! }   The String object (immutable type) doesn't get changed by the method while the StringBuilder object (mutable type) gets changed by the method. Is this all the outcome of String being an immutable type and StringBuilder being an mutable type?  In both scenarios the reference/pointer is passed into the method right? Because the String object is immutable, it creates a new String and because the StringBuilder is mutable (and points to the same object), it changes the same StringBuilder right?

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 tried to ask this question before, but I don't think I was clear. I replaced my recessed lighting with recessed dimmable LED fixtures.  The bulbs are contained in the fixture, and I don't believe they can be changed. Perhaps I'm wrong about that. They are from Commercial Electric, Model T61.  They are 6" recessed LED swivel fixtures and I really don't think there's any way to change the bulbs inside. If I'm wrong and you know a way to change them, I'd so appreciate it.  They are labeled "soft white", but they are bright and harsh.  They are dimmable, but even at the lowest setting they are pretty bright. So are there photo gels or some other way to "warm up" the lighting to more closely match my old halogens which were just beautiful.

I recently bought  white LED reading lamp. I like it a lot, but the "white" light produced is significantly blue; I'll guess its  is about 5000K.  I've noticed that, when this is the only source of light, printed text appears slightly fuzzy, and is more difficult to read than with a standard incandescent reading lamp. My guess is that this is  causing color fringing in my eyes, making it harder to read with this new lamp.  Is there a way to make this lamp less blue using some sort of transparent/translucent filter over the lens? This could filter out some of the blue end of the spectrum, or include a  to convert some of the blue to yellow (as  do). The fluorescence idea would be better, as there'd be less light lost. I don't want to go too far, though; a strongly yellow lamp might be worse for reading than this currently blueish lamp.


I am an formalist in the sense that I think that mathematics is just manipulation of symbols. But I think that this manipulation is motivated by the phantasy of humans: mathematical objects are for me created by human mind. What form of formalist am I?

What would it mean to say that mathematics was invented and how would this be different from saying mathematics was discovered?   Is this even a serious philosophical question or just a meaningless/tautological linguistic ambiguity?


The title pretty much sums it up. I have an application compiled for x86 platforms, which has the /largeaddressaware flag set. Running it on an x64 system, I get the expanded 4gb User Mode virtual memory "for free", without having to specify the /3GB boot option. On an x86 system this would mean that the Kernel Mode memory would only be 1gb, but since x64 systems can address more memory, does the Kernel Mode retain the 2gb or even get bumped up to 3gb?  Edit: To be clear, I'm wondering about per-process limits. The question stems from reading .  Edit 2: This question is not a duplicate of  because that question addresses only the application-accessible memory, not the system accessible memory. If I have been misunderstanding and there is no memory reserved for the system for each process, I'd appreciate it if someone could write that up as an answer. I'm sure I'm not the first to be confused about this.

On Windows, under normal circumstances a 32 bit process can only access 2GB of RAM (or 3GB with a special switch in the boot.ini file). When running a 32 bit process on a 64 bit operating system, how much memory is available? Are there any special switches or settings that can change this?


"  No crash in this case, but I made the mistake of toggling to fullscreen mode on my netbook running Ubuntu 12.04. It's now impossible to escape this "No Menus" view, and it seems to have disabled the popout unity launcher as well. Steps I've already taken:  Alt-Tab to move to a different program, then back - QGIS remains in fullscreen Alt-V, Ctrl-F and F11 get no response I've unistalled QGIS, deleted the /.qgis/ profile data folder, and reinstalled. Still launches fullscreen   To add to the weirdness, it now launches - still in fullscreen - into a different workspace than the active one.  I realize this has the sound of a Unity problem, but it's just this program that has a malfunctioning UI.  Thanks to all the crew; this in no way changes my opinion of QGIS as an essential tool. qgis ubuntu shareedit  asked Sep 13 '12 at 17:28 Bill Morris 1179 "  ***I got the same problem mentioned above and also found a simple solution. I could't post any answer due to lack of reputation in this forum (I am a newbie here). The solution for escaping the Full Screen trap of QGIS on Ubuntu 12.04 is  (1) - press Alt + F4  (2) - QGIS will ask you about Close without saving, cancel or save, however, when you move your mouse arrow to the top of the screen the menu will appear again, then you go to "view" and click the last option "toggle full screen".  That's all!*

No crash in this case, but I made the mistake of toggling to fullscreen mode on my netbook running Ubuntu 12.04. It's now impossible to escape , and it seems to have disabled the popout unity launcher as well. Steps I've already taken:   Alt-Tab to move to a different program, then back - QGIS remains in fullscreen Alt-V, Ctrl-F and F11 get no response I've unistalled QGIS, deleted the /.qgis/ profile data folder, and reinstalled. Still launches fullscreen   To add to the weirdness, it now launches - still in fullscreen - into a different workspace than the active one.  I realize this has the sound of a Unity problem, but it's just this program that has a malfunctioning UI.  Thanks to all the crew; this in no way changes my opinion of QGIS as an essential tool.


I am working on a project where I have a class named dBase with getter and setter methods for fields such as first and last names. However, When I run the code, line 6 of the code portion is highlighted with a java.lang.NullPointerException error, which doesn't help me at all.  How do I make this work? Thanks, in advance  case 3: input.nextLine(); for (int i = 0; i < num; i++){ System.out.println("Enter first name of student " + (i + 1)); String firstN = input.nextLine(); roster[i].setfName(firstN); System.out.println("Enter last name of student " + (i + 1)); String lastN = input.nextLine(); roster[i].setlName(lastN);     }         break;

What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?


As explained on  tags where the Taxonomist badge was awarded show the creator, while the rest don't. This was introduced by .   Link:     Link:   This has no value, and only causes confusion (see question's history and first linked question). All or none would be better.

Some  show who created the tag:    while  don't. I'm pretty sure I created that one as well, if you hover over the timestamp you can see when it was created:    which more or less matches with  where I created the tag:    I understand that some tags like  were probably created by the Community user while the site itself was created (so it ), but some newer tags like   even though  still has an account here.  What's going on here? Would this also mean I wouldn't get a  for  if I ?


Basically the title says everything. There is no action after I post a comment, just a notification that the comment was posted successfully and white screen.   App Version: 1.6.6.2 Device: iPhone 6 OS Version: Version 12.0 (Build 16A366)

Since iOS 11.2 all the way through 12.2 beta 4, if you post or discard a comment on any post on any SE community, the screen will turn white. This has been ongoing continuously for a year now, and it affects both the SE app and the SO app.   You can go back to the previous screen and open the question again, and everything appears as normal. You can also rotate the screen to get the text to come back. Using the arrows to navigate between the question and answers updates the HUD, but the screen remains white unless one of the above is done to get the text back.        UPDATE: After posting anything (comment, answer), the screen goes all white except for the sidebar. Perhaps it is intentional, but I prefer last week’s behavior of going back to the content. Not major, since the sidebar icons still work.


I try to get distinct values in LINQ i try this for this first i create method and then i call this method on page load and assign   regiondrop.DataSource = getregion(); regiondrop.DataSourc=DataTextField="Region" regiondrop.DataSourc==DataTextField="RID"    private List<tab1> getregion()         {             using (T1 tee = new T1())             {             var tempList = tee.tbl1.ToList();             var list = (from ta in tempList             select new { ta.Region, ta.RID }).Select(x => new tbl1             {              Id = x.RID,              reg=x.Region              }).ToList();             return list;             }          }   Data in db like this  RID Region 1   Canada 2   UK 3  London 4  Paris 5  UK 6  Brazil 7  London   Data in drop-down like this   Canada UK London Paris UK Brazil London   but i want data like this   Canada UK London Paris Brazil   any solution?

I am playing with LINQ to learn about it, but I can't figure out how to use Distinct when I do not have a simple list (a simple list of integers is pretty easy to do, this is not the question). What I if want to use  on a list of an Object on one or more properties of the object?  Example: If an object is Person, with Property Id. How can I get all Person and use Distinct on them with the property Id of the object?  Person1: Id=1, Name="Test1" Person2: Id=1, Name="Test1" Person3: Id=2, Name="Test2"   How can I get just Person1 and Person3? Is that possible?  If it's not possible with LINQ, what would be the best way to have a list of Person depending on some of its properties in .NET 3.5?


I've heard that it's quite awkward to say "You're welcome" in actual talks. Is there any alternative for this sentence?

Possible Duplicate:                I'm getting thanked a lot these days and want to find lots of different ways to say you're welcome.  Could for sure mean you're welcome?


My family is an Apple household (Macs and iOS devices), and we are getting into Minecraft. I've been trying in vain to find a definitive answer as to whether there are any options for letting family members use these separate devices to play on common servers or worlds.   It seems doubtful at this point, but I cannot find a trusted source that says, Yep, it's not possible in any way, so you can stop trying to find a solution.  The Minecraft website has a , and both Mac and iOS are listed as sharing common features, namely "Realms," "player-hosted multiplayer servers," and "LAN or WiFi Multiplayer." The Minecraft page on the App Store for iPhone and iPad also advertises “Play with friends on mobile (and) PC...!” (See screenshots.)  I briefly thought that the "Realms" feature was our ticket, since the option was displayed prominently on the interfaces of both Mac and iOS. But when I had trouble getting them to work, I learned (on Arqade and elsewhere) that this common feature is actually restricted. Namely, users can only play with each other if they're running the same Minecraft edition, e.g. Java (on our Macs) or Bedrock/Pocket (on our iPad/iPhone).   I tried looking for Minecraft multiplayer server communities that host both platforms, but I've come up short.   I tried researching what it would take to host a home-based server, but I wasn't able to determine if it would be worth the effort.   We were able to get our iPad and iPhone to run multiplayer on  our LAN/WiFi, but my Mac was unable to see this activity.  Are there ways to make these different Apple devices play nice with each other, or are we SOL?

My kids are playing Minecraft on 2 PCs, creative mode.  They are connected by the way of one of them starts a single player game on the other one than joins that game over the LAN.  Can I, using Minecraft PE on my iPad, join their game as well?


Each time I restart my computer , the nameserver change automatically , and it changed to 127.0.0.1  .  Hence in order to connect to the internet I need to edit the resolv.conf file . After each restart I find my resolv.conf file as  nameserver 127.0.0.1   then I need to edit the file to   nameserver 8.8.8.8 nameserver 8.8.4.4   What is the possible reason behind this and how can I solve it ?  My OS is ubuntu 14.04

I have finally migrated to 12.04 from 7.10. I have one last part to complete but I am stumped. I am using Puppet on each server, and in the past I have included a nameserver address and a search domain name for the puppetmaster in resolv.conf.   search puppetmaster.com nameserver 192.168.1.XXX   In 12.04 resolv.conf gets overwritten when rebooted. I cannot use a static IP for these, so using the /etc/network/interfaces to help me out is a nill point.  # Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8) #     DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN nameserver 127.0.0.1   Is there a way to get resolvconf to handle this either in the head, tail or base? If there is, are there any examples I can use to tweak on my server.   Any help is much appreciated.


I have edited this question because I thought that I had not conveyed my problem in the non edited one.  I want to ask that how 3rd law was so obvious to Newton.How Newton guessed that for an action there is always equal and opposite reaction.How can one so accurately perform an experiment in 17th century and state a law which is universal?How he isolated two bodies in the lab and said that force exerted by two bodies on each other is equal and opposite?Based on some finite experiments how he guessed that it is a universal law.  Well,I am nothing in front of newton to question his laws which are governing whole macroscopic phenomena but I think that I should be able to ask about  these laws which are so obvious  for Sir Issac Newton.  Coming to 2nd law how he guessed that force is directly proportional to time derivative of linear momentum?Well,one could say that he defined force in this manner but my motive is to ask here that if we expand this derivative then we come to know that if mass is not constant then force is directly proportional to rate of change of mass.See it is not very intuitive for anyone to say that if mass is changing with time there would be a force on an object.But one would say that he was a genius so his intuition was very strong but I think that this would not be the answer because according to one's intelligence and intuition he can not frame laws of physics.  By just observing these phenomenon by finite no. of experiments how Newton can universalise these laws for each and every entity in universe.  As per one comment I want to ask here that is 3rd law a consequence of law of conservation of linear momentum?If it is true then why 3rd law is a law?

My father explained to me how rockets work and he told me that Newton's Third Law of motion worked here. I asked him why it works and he didn't answer. I have wasted over a week thinking about this problem and now I am giving up. Can anyone explain why Newton's Third Law works? For reference, Newton's third law:  To every action there is always opposed an equal reaction: or the mutual actions of two bodies upon each other are always equal, and directed to contrary parts.


Logcat says 15th line has error. But I don't know the reason. :( I'm noob so plz explain me softly plz.. Down below is the whole content of logcat. ... 2020-10-17 16:50:03.488 9840-9840/? E/city_implement: Unknown bits set in runtime_flags: 0x8000 2020-10-17 16:50:04.351 9840-9840/? E/AndroidRuntime: FATAL EXCEPTION: main Process: com.example.acticity_implements, PID: 9840 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.acticity_implements/com.example.acticity_implements.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3270) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3409) at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83) at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016) at android.os.Handler.dispatchMessage(Handler.java:107) at android.os.Looper.loop(Looper.java:214) at android.app.ActivityThread.main(ActivityThread.java:7356) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930) Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference at com.example.acticity_implements.MainActivity.onCreate(MainActivity.java:15) at android.app.Activity.performCreate(Activity.java:7802) at android.app.Activity.performCreate(Activity.java:7791) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1299) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3245) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3409) at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83) at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016) at android.os.Handler.dispatchMessage(Handler.java:107) at android.os.Looper.loop(Looper.java:214) at android.app.ActivityThread.main(ActivityThread.java:7356) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930) ... xml code of buttonRed is this.


Totally confused. In an apex controller, adding a new parameter to the constructor for a class somehow causes this error. How can I get more information?  It doesn't appear to be the same issue as linked to, even though the gack ID is the same.  I have an apex controller being called from a lightning component. This controller has a inner class ProjectData, and a list of these are returned. This works fine.  The error occurs upon changing 2 lines of code. All it takes is adding a single parameter to the constructor, i.e. changing  public ProjectData(Project__c proj, String client, Boolean favourite)   to  public ProjectData(Project__c proj, String client, Boolean role, Boolean favourite)   I then added a True value to the only place this constructor is called. Upon refresh, I get the error. There is no difference to any objects other than this one change, so it can't be a permissions error.

Opening Lightning Application which refers to SObject for which current running user doesn't have permission raises internal server error with Gack Id -227057212  Steps to reproduce:   Create custom object Custom_Object__c Create Apex Class   public class PILexCont { @AuraEnabled public static Custom_Object__c performBusinessLogic( ){     Custom_Object__c record = new Custom_Object__c();     insert record;     return record; } }  Create an App  <aura:application controller="PILexCont"> <aura:attribute name="record" type="Custom_Object__c"/> <button onclick="{!c.performLogic}">Perform business logic</button> </aura:application>  With Javascript Controller   ({ performLogic : function(component, event, helper) { var action = component.get( "c.performBusinessLogic" );  action.setCallback(this, function(response  ) {     var state = response.getState();     if (component.isValid() && state === "SUCCESS") { /* component.isValid() simply, checks if the component has been destroyed or not. (http://salesforce.stackexchange.com/questions/81998/what-does-the-lightning-component-method-component-isvalid-do) */         alert('component valid, state success');          var record = response.getReturnValue();         component.set("v.record", record );      } else {         alert('error?'  );     }   }); $A.enqueueAction(action); } })  Open an app by a user who doesn't have permission to Custom_Object__c      Obtain the error         An internal server error has occurred     Error ID: 1557802061-15979 (-227057212)


How does a rocket push against its exhaust? Does the reaction come from the rocket nozzle or as a result of the imbalance of forces in the combustion chamber?

I know Newton's third law of motion might be the answer for this but still I am wondering how the rockets could thrust in the empty space and move in the opposite direction. I guess an astronaut wouldn't be able to push in the empty space with his hands or legs to move himself, but with a rocket engine it's possible. How? What might be the explanation for this in General Relativity?


Why doesn't Stack Exchange develop an IM-like rich client for us to more conveniently ask questions and get answers in real-time?  I want to join this open source project if somebody is interested.

t's actually a good monetizing idea. Make it possible to sign up as an expert (on your tag badges, one would presume) with available hours, set an hourly fee (billed in 15 minutes increments), SE takes a cut and let the "Ask an expert" commence.  Edit: so many downvotes, so quick! Why?


The point of potential energy is to say that the amount of KE in an object doesn't resemble all it's potential to do work(like a battery,  or gasoline they both have ability to do work even though their momentum is 0).   This contradicts the concept of conservation if momentum,  which says that the amount of potential to do work,  is always there as speed and mass.   Here are some examples.   When you hold a ball above the ground it has Some PE. When you drop the ball, it  loses PE and gains KE, increasing the ball's momentum.  Clearly the momentum wasn't conserved.  When a driver hits the gas pedal in his car,  it starts accelerating,  turning PE of the fuel to KE of the car,  increasing the car's momentum. Before he hit the gas pedal,  the car had 0 momentum (relative to earth).  The momentum wasn't conserved.   There are thousands of examples like those.   Where did my intuition go wrong?

I did lot of searching but couldn't find any textbook nor any webpage which could clarify my doubt. Maybe my doubt is insanely stupid and I was dumb for not realizing it at the first place.  The negative of the work done by the electrostatic field in bringing a charge from infinity to a point is called electric potential.   Let us assume that there is a positive charge at the origin. Let work done by the external force to bring a positive from infinity to a point P close to the origin be W. And hence work done by the field to bring a positive charge from infinity to the point P will be -W.  If I did work W to bring the charge from infinity or if the field brought the charge from infinity, either way the change in potential energy will be same.  In case of work done by the field, we say that the work done is stored in the form of electrostatic potential energy.  In case of work done by the external force, we say that the work done was positive and the energy was taken by some external source.  In the above case, I did work W in bringing it & the field did work -W on the charge trying to push it away so I did positive work of W & the field did negative work of W. We can say that the work done by the field was stored as potential energy.   Where did the work done by the external force (me) go?  I can summarize the whole doubt in the following line: I did work W to bring an charge towards another unlike charge, and therefore the field also did work -W, the net work done on the charge is 0. But there is still a change in potential energy. Why did the potential energy change? Isn't conservation of energy being violated here?  Please clarify my doubt (I do understand that there is a horrible conceptual error in one of my arguments but I do not know which one it is). If I am not wrong this has nothing to do with electrostatics rather has to deal with field theory/inverse square law. I believe I will be encountering the same problem again when I would be studying another force, maybe gravitational, which obeys inverse square law.  Thank You


:  .... Simple is better than complex.  ....   So why does it use both double quote " " and single quote ' ' to indicate something is a string literal.  I was lost when I typed:  x = "aa" x   And saw:  'aa'   But not:  "aa"   When I saw the above philosophy, I doubted it. It needs some explanations.

According to the documentation, they're pretty much interchangeable.  Is there a stylistic reason to use one over the other?


I've recently installed VS 2012 Professional.  When i try to build my MVC4 Web Project. It doesn't recognize error in razor view when i do "Build" or "Re-Build".  Example :  I removed a namespace from the project / or say renamed it. i build the solution, it gave me errors in all cs files, which i fixed by changing the namespace. The entire solution build successfully. When i run the project it gave me Compilation Error saying that namespace not found, because the old namespace was still referred in some of the views (*.cshtml files).  Expected Solution :  I wish when i do "Build" or "Re-Build", it should recognize such errors and show me along with any other errors.  This was working fine with VS 2010, am i missing any configuration?  Thanks In Advance !! Amit  Edit I found the answer myself, i think it was early to post the question :       Another Problem      After changing value to True in .csproject file, when i start building   the project it shows error, but it shows only one error at a time.   let's say, i've 5 errors in total 3 views. it would just show me one   error. Is there any solution so that it shows all the 5 errors ?

I want an msbuild task to compile the views so I can see if there are compile time errors at well... compile time.  Any ideas?


Problem 15-24 of Michael Spivak's Calculus (first edition) is      Prove that $|\sin x - \sin y|< |x-y|$ for all numbers $x$ and $y$. The   same statement, with $<$ replaced by $\leq$, is a very straightforward   consequence of a well-known theorem; simple supplementary   considerations then allow $\leq$ to be improved to $<$.   OK, so $|\frac{d}{dx} \sin (x)|\leq 1$, so the mean value theorem gives us the weak inequality. The strict inequality seems intuitively clear to me when I draw a line of slope 1 through the origin and compare it to the sine graph. But I'm trying to make this rigorous.  There are some ideas , but I suspect the author had something more elementary in mind to strengthen the inequality. Note that this is before the fundamental theorem of calculus has been introduced in the book. Any ideas?

From Spivak's Calculus:     Prove that $|\sin x - \sin y| < |x - y|$ for all $x \neq y$. Hint: the same statement, with $<$ replaced by $\leq$, is a straightforward consequence of a well-known theorem.   Now, I might even be able to prove this somehow (?), but I can't seem to figure out what "well-known theorem" the author is alluding to here... any hints?


Please, I have used rm * in a script shell, it deleted all my files? (a typo)  Is there a solution to recover these files ?

Can we undo operations done in a terminal, for example, file deletion through rm?  Solutions obtained:  Aliasing Undelete utilities Backup utilities  Versioning (FUSE)


Im working on a project that under SVN. i need to logout from svn and logged in as a new user to checkin files to the subversion.  i tried  $ svn co svn://hostname/myproject myproject --username user_name no luck  Thanks Roshan.

I'd like to know how to get Subversion to change the name that my changes appear under.  I'm just starting to use Subversion. I'm currently using it to version control code on an XP laptop where I'm always logged in under my wife's name. I'd like the subversion DB to show the changes under my name.  Later on I'll replicate the DB so it is accessible to the whole house. My wife uses the office computer where she is always logged in under my name. I'll probably set it up so that it automatically checks in modified documents... preferably under her name.  Eventually I'll probably be using it from a linux machine under another username.  Is there some way to modify the user environment to change the user name that Subversion calls you? I'd expect something like setting SVN_USERNAME='Mark' which would override however it usually gets the name.  Update: It looks like the --username flag that Michael referred to does work to change the name reported by "svn stat", even for local file: repositories. In addition, it is sticky so you don't need to specify it for the next command. I even rebooted and it still used the "--username" value from my previous boot.


I have a Garmin Nuvi 1350 GPS and would like to know if I could download maps from the garmin Website like I do in Windows. In Windows, you need the Garmin Express app, but no such thing seems to exist in Ubuntu 12.04.

Is there a way to update the GPS' (Garmin nüvi 255) maps with Ubuntu?  I'm hoping for a free (as in doesn't cost anything... I already bought the darn thing) solution.  I have installed the plugin, and it works with myGarmin, however I cannot register my device because I need to install whatever Windows software (Garmin Express) it requires, and all I can find is "Purchasing maps update"...  This is my first GPS and I just want to get the most recent maps as my local streets don't show up.


I know nothing about relativity but I cannot accept that there is a phenomenon called . However I have no problem with it because of mathematics behind it. I have no problem if time is dilated, because I don't know what time is. But I wonder when they say a clock will work slowly with respect to the other same clock if its speed is higher.   Which kind of clocks they mean? Analog clock, digital clock, etc. As far as I know some mechanical clocks work by a torsion spring inside them. So, how does the material of the spring know that it must unroll slowly at higher speed? Does higher speed change chemical structure or physical properties of the material of the spring?

Please will someone explain what time dilation really is and how it occurs? There are lots of questions and answers going into how to calculate time dilation, but none that give an intuitive feel for how it happens.


I got one of those phone boosters for Android but it looks like it does not work very well because when I run a clean it stops at 88% or somewhere and immediately tells me that I have to clean again.  I figured that it is some kind of bug or that an app is using a lot of RAM and it can't be cleaned.  Is there a way to clean more RAM so my phone can get faster?

I have a Samsung Galaxy S (AT&T Captivate) that is rooted.  I have various ways to tweak the amount of free RAM the OS leaves on the phone.  The default is 48 MB, but I was wondering if I could actually go lower without impacting phone performance.  Are there guidelines posted anywhere, or that can be deduced based on knowledge of the Android platform?  Or should I trust that the default settings are appropriate?  I understand that when it comes to free RAM, more isn't necessarily better, but I understand that there is still a threshold that I don't want to dip below.   I'm running a 2.3.6 Gingerbread based ROM.  For what it's worth, I'm running the Zeam launcher.


I'm preparing some marketing materials for my boss, and one section contains the phrase "Here are a few examples:". The list that follows contains two items, which strikes me as being incorrect, though I can't find much evidence of this.  Is it semantically correct to refer to two items as "a few"? Is there a solid rule for this, or is it just personal preference?  Edit - As Armen correctly pointed out, this question is about semantics rather than grammar. I changed my phrasing to reflect this.

What does “a couple” mean to you, and what does “a few” mean to you?  Is there a proper way to use these words?  It was striking to hear that “a couple” meant two (2) to someone.  My reaction was, “how/why do you make a short word longer by adding an extra syllable to just say ‘two?’”  I think Few: 2-3, Couple 4-6, Several 7+.  What are your thoughts?


I recently had a glitch with the game so I had to delete it. When I got it back, it made me start all over and I can't sign into my old account that was on my Game Center. Is it possible to log in to my old account or do I have to start over?

How do I login to the Gamecenter on PewDiePie's Tuber Simulator, if you have not done it when they asked?


My question is find all homomorphism $ f: \Bbb Q \to \Bbb R$.  I think I should use ring isomorphism theorem to do this problem, but I just don't know how to do this.

Let $A$ be a ring. I'm trying to prove that there is only one ring homomorphism (different from the zero one) from $\Bbb Q$ into $A$ or there are no ring homomorphisms between $\Bbb Q$ and $A$.    I have proven that if $A=\Bbb Z$ or $A=\Bbb R$ then there are no ring homomorphisms between $A$ and $\Bbb R$ (not taking into account the zero one) but I don't know how to prove it for any $A$.


I purchased a wifi thermostat and cannot located the common wire. My unit is old and is a Coleman 70 with no terminals inside labeling the wires.     As you can see in the second image, there is a blue wire that is not being used that goes to my thermostat. I am trying to use this as a common wire, I am just unable to determine where this wire connects to.  THank you for the help.

So, the spiffy new wi-fi thermostats want power on the C wire from thermostat, but the old thermostat doesn't have a C wire at it.  What's the easiest way to add the C wire/24 volt to the thermostat location?


Is there a way to ping an IP , and know the PC mac address of this IP ?  For exapmle in my network there is a printer which has the ip 192.168.1.99 (dynamic) , i need to   its mac address to give it a reservation in  dhcp .

How can I list all  and their associated  of the machines connected to my local network (LAN)?


I have a MacBook air and want to attach a external graphics card but it's already attached to a monitor, so the thunderbolt port is in use so does anyone know of a hub-like device to make my 1 thunderbolt port have 2 plugs. For clarification I want to take the 1 thunderbolt port in my Mac and add a hub (like 100$ or less) so I can instead have 2 thunderbolt ports. (If it's not clear, I want you to submit possible hubs I can buy (off Amazon if possible))

Apple has just announced the new MacBook Airs, Mac mini, and Thunderbolt display. One of the features of the Thunderbolt display that caught my eye was its ability to daisy-chain two displays together from one Thunderbolt port (on a MacBook Pro).  I already have two 24" monitors and I don't feel like paying for two £900 displays. I worked out that all I need is a Thunderbolt hub/splitter so that I can plug the two cables that emerge into mini DisplayPort-to-DVI adapters.  Does anyone know of any Thunderbolt hubs or splitters? Or does anyone know of an alternative method?


The option to select the "List" type on the new custom settings screen is not available (disabled and set to "Hierarchy.") I see a notification to use Custom Metadata types, however they will not work for this particular application because the data will need to be modified by a test class.   Is there a way to create new list custom settings?

I am trying to create a new custom setting in salesforce but the Setting Type field is greyed out and fixed to Hierarchy. What could be the possible problem?


How I can return from function to main function 3 variable (c++). In the code need be function with take a,b,c value [funk()] and then returning to the main and then those values taking into function [rezult()] My code: #include <iostream> #include <cmath> using namespace std; int funk(); float rezult(float a, float b, float c){     //ax^2+bx-c=0     float D, x1, x2, help;     /*     D=b^2-4ac     x1 = ((-1) * b - sqrt(D)) / 2 * a     */     D = b * b - 4 * a * c;     if (D > 0){         help = (-1) * b - sqrt(D);         x1 = help / (2 * a);         help = (-1) * b + sqrt(D);         x2 = help / (2 * a);         cout << "x1 = " << x1 << endl;         cout << "x2 = " << x2 << endl;     }else if (D == 0){         x1 = ((-1) * b) / (2 * a);         cout << "x1,2 = " << x1 << endl;     }else{         cout << "x1,2 = n" << endl;     } }  int main() {     float a = 0.00, b = 0.00, c = 0.00; funk(); cout << a << b << c<< endl; rezult(a, b, c); return 0; } funk(){     float a, b, c;     cout << "a: ";     cin >> a;     cout << "b: ";     cin >> b;     cout << "c: ";     cin >> c;     return a, b, c; }  But in function funk(); code don't retuning a,b,c values. Where is mistake? a,b,c need be float type

Is there a preferred way to return multiple values from a C++ function?  For example, imagine a function that divides two integers and returns both the quotient and the remainder.  One way I commonly see is to use reference parameters:  void divide(int dividend, int divisor, int& quotient, int& remainder);   A variation is to return one value and pass the other through a reference parameter:  int divide(int dividend, int divisor, int& remainder);   Another way would be to declare a struct to contain all of the results and return that:  struct divide_result {     int quotient;     int remainder; };  divide_result divide(int dividend, int divisor);   Is one of these ways generally preferred, or are there other suggestions?  Edit: In the real-world code, there may be more than two results.  They may also be of different types.


How can we prove that $$\sum_{i=1}^n\cos\left(i\pi\frac kn\right)=\begin{cases}n&\text{, if }k=0\\ 0&\text{, if }k\in2\mathbb N\setminus\left\{0\right\}\\-1&\text{, if }k\in2\mathbb N+1\end{cases}$$ where $n\in\mathbb N$. I suppose it's an easy application of some trigonometric identities, but I wasn't able to figure it out.

Possible Duplicate:          Prove $$\cos(\alpha) + \cos(\alpha + \beta) + \cos(\alpha + 2\beta) + \dots + \cos[\alpha + (n-1)\beta] = \frac{\cos(\alpha + \frac{n-1}{2}\beta) \cdot \sin\frac{n\beta}{2}}{\sin\frac{\beta}{2}} $$


My question is somewhat similar to . However, my question is different because of the following:   The question was not asked in a specific flavor. It doesn't contain any of the regex pattern in JavaScript flavor, except one which only validates two level of nesting. It only contain some algorithms, which I don't need because I'm trying to learn Regex.     I'm trying to learn Regex by validating an expression as "Balanced Parenthesis".     Balanced Parenthesis is an expression in which every ( is closed with a corresponding )   For example, the below expressions are valid:  (1+2)*(2+5) (1+2(3+4)-6)/(2+4) ((()))   But, (3+4() is invalid. For sake of simplicity, assume the terms inside the parenthesis to be digits and operators.    I'm using JavaScript regex. So, I tried the below regex. However, it .  ^(\((?:[^()]|\1*)\)[^()]*)+$   But, when I tried the below PCRE regex, it .  ^(\((?:[^()]|(?1))*\)[^()]*)+$   The only syntactical difference in both the regex was how the first capturing group was re-used: \1 in JS and (?1) in PCRE. I know that \1 isn't a kind of subroutine, so are there any alternatives present in JavaScript, except repeating the whole pattern again?  I know a way using variables inside RegExp constructor. But, my regex is nested and so that one is ruled out.

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


I have found in some test problem:  Given $0 < a < b < 1$, can we conclude that $\sqrt{a + b} < \sqrt{a} + \sqrt{b}$?  I divide the combination of a and b into a few cases. Then, see what happens.  case 1 : $a \rightarrow 0$ and $b \rightarrow 0$  When $a$ approaches to zero and $b$ approaches to $a$ (which is zero), the expression will be evaluated as $\sqrt{0 + 0}$ and $\sqrt{0} + \sqrt{0}$. Since $0 = 0$, this case cannot conclude that $\sqrt{a + b} < \sqrt{a} + \sqrt{b}$  case 2 : $a \rightarrow 1$ and $b \rightarrow 1$  When $b$ approaches to one and $a$ approches to $b$ (which is one), the expression will be evaluated as $\sqrt{1 + 1}$ and $\sqrt{1} + \sqrt{1}$. Since $\sqrt{2} < 2$, then this case concludes that $\sqrt{a + b} < \sqrt{a} + \sqrt{b}$  case 3 : $a \rightarrow 0$ and $b \rightarrow 1$  When $a$ approaches to zero and $b$ approches to one, the expression will be evaluated as $\sqrt{0 + 1}$ and $\sqrt{0} + \sqrt{1}$. Since $1 = 1$, then this case cannot concludes that $\sqrt{a + b} < \sqrt{a} + \sqrt{b}$  case 4 : $a \rightarrow b$  When $a$ approaches to $b$ the expression will be evaluated as $\sqrt{b + b}$ and $\sqrt{b} + \sqrt{b}$. Since $\sqrt{2b} < 2\sqrt{b} $, then this case concludes that $\sqrt{a + b} < \sqrt{a} + \sqrt{b}$    From above cases, am I still missing some point? If not, How should I write the conclusion from that pieces of thinking mathematically? Because I instinctively believe that $\sqrt{a + b} < \sqrt{a} + \sqrt{b}$ should be true (and not $\sqrt{a + b} \leq \sqrt{a} + \sqrt{b}$).

I thought of this a while ago, but can't make up a proof or a counterexample. Does anyone know more about this?  $$\sqrt{a+b}  \le \sqrt a + \sqrt b , \forall a,b \in \mathbb R_+$$  Moreover, what happens with more variables? Say:  $$\sqrt{x_1+x_2+...+x_n} \le \sqrt x_1 +\sqrt x_2 + ... + \sqrt x_n $$  with $ x_i \in\mathbb R_+ \forall i \in \{1,2,...,n\} $  Or when $i = \mathbb N$  PS: I tried looking on the internet for this but I don't know how I would call this.


I want a true deep copy. In Java, this was easy, but how do you do it in C#?

I want to do something like:  MyObject myObj = GetMyObj(); // Create and fill a new object MyObject newObj = myObj.Clone();   And then make changes to the new object that are not reflected in the original object.  I don't often need this functionality, so when it's been necessary, I've resorted to creating a new object and then copying each property individually, but it always leaves me with the feeling that there is a better or more elegant way of handling the situation.  How can I clone or deep copy an object so that the cloned object can be modified without any changes being reflected in the original object?


I'm reading Schwartz QFT, Chapter 18 (mass renormalization) and I'm confused about the equations about on-shell subtraction/pole mass. He writes:  The renormalized propagator should have a single pole at $\not p = m_P$ with residue $i$. The location of the pole is a definition of mass.  But $\not p$ has two spinor indices (i.e. a 4x4 matrix) while $m_P$ is just a number, so how does this make sense? I thought maybe it means $\not p = m_P \mathbf{1}$, but in the Weyl representation for instance, the $\gamma^\mu$ have zeros on the main diagonal so $p_\mu \gamma^\mu$ can't be proportional to $\mathbf{1}$ (unless it's all zeros). He also goes on to write the equation, $$i = \lim_{\not{p}\to m_P} (\not p - m_P) \frac{i}{\not p - m_R + \Sigma_R(\not p)} = \lim_{\not{p} \to m_P} \frac{i}{1 + \frac{d}{d\not{p}} \Sigma_R(\not p)} \tag{18.41}$$ I don't understand what $\lim_{\not{p}\to m_P}$ and $\frac{d}{d\not{p}}$ mean if $\not p$ is a 4x4 matrix. Is it a limit/derivative in the 16-dimensional space of the matrix entries? Edit: It did occur to me that maybe $\not p = m_P$ is a shorthand for $m_P = \sqrt{p^2} = \sqrt{\not p^2}$. However, for there to be a pole at $\not p = m_P$ they would have to coincide fully. $m_P = \sqrt{p^2}$ seems insufficient.

In the theory of free scalar bosons (KG field) it is a basic result that the propagator $\Delta(p)$ has poles at $p^2=m^2$, with residue $1$ (or any other constant, depending on conventions). Thinking of $p^2$ as a variable is acceptable because it can be shown that the propagator is a function of $p^2$, even in the interacting case.  On the other hand, in the theory of free spinor fields (Dirac field), we can show that the propagator is not a function of $p^2$, but of $\not p$, so we can't use the $p^2$ trick. Conventions aside, the propagator is $$ S(p)=\frac{\not p+m}{p^2-m^2+i \epsilon} $$  It is clear that we cannot think of poles as $p^2\to m^2$, because $S(p)$ depends on $p$ in a non-so-trivial way. The usual solution is to think of $S$ as a function of $\not p$, as if $\not p$ was a number instead of a matrix, thus writing $$ S(\not p)=\frac{1}{\not p-m+i\epsilon} $$ and, again, we find a pole at $\not p=m$, with residue $1$. I think this is not mathematics. This is just nonsensical to me (may be I'm too skeptic, and we can give a meaning to this last formula).  In an interacting theory, we define the field strength normalisation $Z$ as the residue of the propagator at the poles: $$ \Delta(p^2)=\frac{Z}{p^2-m^2+i\epsilon}+\int_{M_\text{thresh}^2}^\infty \mathrm d\mu^2\rho(\mu^2)\frac{1}{p^2-\mu^2+i\epsilon} $$ $$ S(\not p)=\frac{Z}{\not p-m+i\epsilon}+\int_{M_\text{thresh}^2}^\infty \mathrm d\mu^2\frac{\not p\rho_1(\mu^2)+\mu \rho_2(\mu^2)}{\not p^2-\mu^2+i\epsilon} $$  Now, I don't understand what's the proper definition of $Z$ as a residue. In what sense is it a residue? What's the variable? I just can't accept it is a residue as $\not p\to m$. Do we really take this "think of $\not p$ as a variable'' seriously? Is it possible to formalise these matters, by thinking of a residue for an actual variable (as $p_0$)?  Perhaps the $\not p$ trick is just that: a trick, which may simplify calculations, but such that it can be shown that the actual result, found by a more standard procedure, is the same. Is this the case? If so, what is the correct procedure?  (I would really appreciate if the answers don't assume that we can boost to the rest frame of the particle, as I'd like it to be as general as posible. I want to take into account the possibility of $m=0$, so please don't boost into $k=(m,\boldsymbol 0)$ if it's not really necessary)


I am trying to find values of $r>0$ such that $\lim\limits_{n\rightarrow \infty} \sum\limits_{k=1}^{n^2}\frac{n^{r-1}}{n^r+k^r}$ is finite. I have tried to use integral methods for this limit such as $\sum\limits_{k=1}^{n^2}\frac{n^{r-1}}{n^r+k^r}=\sum\limits_{k=1}^{n}\frac{n^{r-1}}{n^r+k^r}+\sum\limits_{k=n}^{n^2}\frac{n^{r-1}}{n^r+k^r} = \frac1n\sum\limits_{k=1}^{n}\frac{1}{1+(\frac kn)^r}+\sum\limits_{k=n}^{n^2}\frac{n^{r-1}}{n^r+k^r}$. So the first term, I could use the integral method to estimate. However, the second one is hard to evaluate. Could you please help me with this? Thanks

Let $r>0$ and   $$ a_n(r)=\sum_{k=1}^{n^2}\frac{n^{r-1}}{n^r+k^r} $$ When do we have   $$ \lim_{n\to\infty}a_n(r)<+\infty? $$     One can write $$ a_n(r)=\frac1n\cdot\sum_{k=1}^{n^2}\frac{1}{1+\left(\frac{k}{n}\right)^r} $$ which looks simpler but I don't see how it would help. Also I tried to bounded $\{a_n(r)\}$ but I don't see how.   [ADDED:](Thanks to Daniel) It does look like a Riemann sum. I think this is not an integral on a finite integral. Instead it looks like $$\int_0^\infty\frac{1}{1+x^r}dx.$$ But I'm not sure if this the corresponding integral or not.


I am working on an enterprise wiki site collection inside SharePoint 2013, and sometimes especially when modifying the wiki page name , users will get the following exception :-    I checked the logs and i find the following error "UserAgent not available, file operations may not be optimized. ... ". so can anyone adivce on this please? Thanks  Edit   Here is the log file uploaded to onedrive after enabling verbose logging , correlation id = 4bce009d-3c69-c0b7-30fc-0153080d3219 :-    i found the following 2 exceptions inside the log file :-   04/27/2015 12:51:36.38*   w3wp.exe (0x4640)                           0x225C  SharePoint Foundation           Files                           ak8dj   High        ...ecutionStep.Execute()     at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)     at System.Web.HttpApplication.PipelineStepManager.ResumeSteps(Exception error)     at System.Web.HttpApplication.BeginProcessRequestNotification(HttpContext context, AsyncCallback cb)     at System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest wr, HttpContext context)     at System.Web.Hosting.PipelineRuntime.ProcessRequestNotificationHelper(IntPtr rootedObjectsPointer, IntPtr nativeRequestContext, IntPtr moduleData, Int32 flags)     at System.Web.Hosting.PipelineRuntime.ProcessRequestNotification(IntPtr rootedObjectsPointer, IntPtr nativeRequestContext, IntPtr moduleData, Int32 flags)     at System.Web.Hosting.UnsafeIISMethods.MgdIndicateCompl...  4bce009d-3c69-c0b7-30fc-0153080d3219 04/27/2015 12:51:36.49    w3wp.exe (0x4640)                           0x225C  SharePoint Foundation           Runtime                         tkau    Unexpected  System.NullReferenceException: Object reference not set to an instance of an object.    at Microsoft.SharePoint.Publishing.WssObjectCache.RemoveItemFromCache(Guid webId, Guid itemGuid, Boolean isList)     at Microsoft.SharePoint.Publishing.WssObjectCache.HandleChanges(SPChangeCollection changes)     at Microsoft.SharePoint.Publishing.CacheManager.CheckForChanges(SPSite site, Boolean forceGetChanges)     at Microsoft.SharePoint.Publishing.CacheManager.GetManager(SPSite site, Boolean useContextSite, Boolean allowContextSiteOptimization, Boolean refreshIfNoContext)

I have two sites that were originally migrated from SPS2003.  It worked well in SharePoint 2007 and even on SharePoint 2010,  however when we migrated it to SharePoint 2013,  the home page throws following errors on the ULS Log.     5/24/2013 09:57:46.62  w3wp.exe (0x0D50)   0x1D24  SharePoint Foundation   Files   ak8dj   High   UserAgent not available, file operations may not be optimized.    at Microsoft.SharePoint.SPFileStreamManager.CreateCobaltStreamContainer(SPFileStreamStore spfs, ILockBytes ilb, Boolean copyOnFirstWrite, Boolean disposeIlb)     at Microsoft.SharePoint.SPFileStreamManager.SetInputLockBytes(SPFileInfo& fileInfo, SqlSession session, PrefetchResult prefetchResult)        05/24/2013 09:57:46.62 w3wp.exe (0x0D50)   0x1D24  SharePoint Foundation   Cobalt  ajoii   Medium   Mapping Store error to Cobalt error. [Store Error: System.NullReferenceException: Object reference not set to an instance of an object.     at Microsoft.SharePoint.CoordinatedStreamBuffer.SPCoordinatedStreamBufferFactory.CreateFromDocParams(SqlSession session, Guid guidSiteId, Int32 cbContent, Nullable1 parentId, Guid docId, Nullable1 level, SPChunkedArray`1 rgbContent, Byte[] rgbRbsId, Int64 bsn, Byte partition, Int32 pageSize, Boolean bStartFilling)        05/24/2013 09:57:46.62 w3wp.exe (0x0D50)   0x1D24  SharePoint Foundation   Cobalt  aintx   High    Failed in CobaltStream.LockBytes: ErrorException --- Error: Unknown (Win32=0x80004003) --- Error message: System.NullReferenceException: Object reference not set to an instance of an object.     at Microsoft.SharePoint.CoordinatedStreamBuffer.SPCoordinatedStreamBufferFactory.CreateFromDocParams(SqlSession session, Guid guidSiteId, Int32 cbContent, Nullable1 parentId, Guid docId, Nullable1 level, SPChunkedArray`1 rgbContent, Byte[] rgbRbsId, Int64 bsn, Byte partition, Int32 pageSize, Boolean bStartFilling)     at         05/24/2013 09:57:46.64 w3wp.exe (0x0D50)   0x1D24  SharePoint Foundation   Files   ak8dj   High    UserAgent not available, file operations may not be optimized.    at Microsoft.SharePoint.SPFileStreamManager.CreateCobaltStreamContainer(SPFileStreamStore spfs, ILockBytes ilb, Boolean copyOnFirstWrite, Boolean disposeIlb)     at Microsoft.SharePoint.SPFileStreamManager.SetInputLockBytes(SPFileInfo& fileInfo, SqlSession session, PrefetchResult prefetchResult)     at         05/24/2013 09:57:46.64 w3wp.exe (0x0D50)   0x1D24  SharePoint Foundation   Database    ab1a9   High    Failed to get document content data. System.NullReferenceException: Object reference not set to an instance of an object.     at Microsoft.SharePoint.CoordinatedStreamBuffer.SPCoordinatedStreamBufferFactory.CreateFromDocParams(SqlSession session, Guid guidSiteId, Int32 cbContent, Nullable1 parentId, Guid docId, Nullable1 level, SPChunkedArray`1 rgbContent, Byte[] rgbRbsId, Int64 bsn, Byte partition, Int32 pageSize, Boolean bStartFilling)     at   I could not find any materials related to this on the internet,  I am not even sure if it has to do something with SPS2003 compatibility.  Any help pointers?


Can you help me recalling the title of a sci-fi movie I saw first in 2000:  About the plot:   A group of young people can access a (recorded) memory of a man (the man is possibly dead) They must dig through the memories of him, but I forgot the purpose of it. The memories are about the childhood of the man The room in which they access the mans memories is blueish and only the head of the man is visible on a kind of screen   It looks like the Short Movie '', but I miss the childhood memories in this movie and the group of young people investigating. As far as I know, the movie is not part of any series  I would very much like to see the movie again.

Some years ago I saw part of an episode of a sci-fi miniseries (maybe British) with a brain in some research laboratory.  It was the brain of a man who died many years ago.  The time is in the future (I think), and the scientists managed to resurrect the brain with some kind of electrical futuristic equipment, some wires and sensors. We see strange flashbacks of the past mixed with unfocused images of the scientist.  The brain is kept inside a liquid and gradually with time he understands what happened, that he was brought to life, and connected to a some kind of equipment that allows him to see, watch, and think. The scientists explain everything to him and I remember that in the end he gets some kind of body but I'm not sure.  Does anybody remember the name of this nineties TV series or made-for-TV movie?


Let $G$ be a finite group. Explain why it is impossible for $G$ to have one Sylow $2$-subgroup isomorphic to $\mathbb{Z}_4$ and another Sylow $2$-subgroup isomorphic to $\mathbb{Z}_2 \times \mathbb{Z}_2$.  My idea: By the second Sylow theorem we know that the Sylow $p$-subgroups are always conjugate to each other; and thus, they have the same order. So $\mathbb{Z}_4$ and $\mathbb{Z}_2 \times \mathbb{Z}_2$ must be conjugate. In other words,  $\mathbb{Z}_4$ and $\mathbb{Z}_2 \times \mathbb{Z}_2$ are isomorphic, wich is impossible. Is this correct?

The Sylow theorems say that all $p$-Sylow subgroups are conjugate.   Is that the only thing they are conjugate to? In other words could a $p$-Sylow subgroup also be conjugate to something that is not a $p$-Sylow group?   Or does the fact that every element with order dividing $p$ is in a $p$-Sylow group mean that that is never possible?


I have tried refreshing and everything, but I still can't get rid of this so am starting to think that this is server-side rather than me (and many others are saying that hey have it too):    And it is not just the chat rooms, the whole SE chat site is messed up...:    I am running Firefox 41 on Ubuntu GNOME 15.10.  Information Update:  I am also noticing similar problems on this site (where I am posting this question).

When loading TeX.SX over TLS (e.g. ) with HTTPS Everywhere, images are not displayed.  Firefox shows this error (e.g. for ):     An error occurred during a connection to i.stack.imgur.com. Peer   reports it experienced an internal error. (Error code:   ssl_error_internal_error_alert)


I am taking a course in classical mechanics, and I was wondering what the difference between the two time derivatives $\frac{\text{dL}}{\text{dt}}$ and $\frac{\partial \text{L}}{\partial \text{t}}$ in a Lagrangian mechanics?

What is the difference between implicit, explicit, and total time dependence, e.g. $\frac{\partial \rho}{\partial t}$ and $\frac{d \rho} {dt}$?  I know one is a partial derivative and the other is a total derivative. But physically I cannot distinguish between them. I have a clue that my doubt really might be understanding the difference between implicit, explicit and  total time dependence.


I have a script that I want to run on startup.  This script launches vms using sudo VBoxManage.  How can I a) Execute this vm start script on the computer startup and b) make sure the sudos don't need me to actually type in a password.    I figured rc.local somehow but not sure how to handle the fact that it requires sudo to run VBoxManage with

I'm running a remote bash script (using ssh -t 'bash doscript.sh'). In "doscript.sh" I have a sudo su anotheruser. At that point, the script seems to push a shell and I'm left in that "interactive" script and the rest of my script (doscript.sh) doesn't run unless I type "exit". Is there a workaround that gets around this problem?  Thanks in advance.  Here is the contents of my test script "doscript.sh":  sudo su diy cd pwd whoami exit whoami


Prove that $$\limsup(a+b) \leq \limsup(a) + \limsup(b)$$ and $$\liminf(a+b) \geq \liminf(a) + \liminf(b)$$ where $a,b:\mathbb{N}\to \mathbb{R}$ are two bounded sequences.  I'm not sure where to begin on this proof.

I am stuck with the following problem.     Prove that $$\limsup_{n \to \infty} (a_n+b_n) \le \limsup_{n \to \infty} a_n + \limsup_{n \to \infty} b_n$$   I was thinking of using the triangle inequality saying $$|a_n + b_n| \le |a_n| + |b_n|$$ but the problem is not about absolute values of the sequence.  Intuitively it's clear that this is true because $a_n$ and $b_n$ can "reduce each others magnitude" if they have opposite signs, but I cannot express that algebraically...  Can someone help me out ?


After making my hot sauce it tends to separate leaving a vinegar at the bottom and sauce at the top. When I shake it up then it's back to normal. Any suggestions?

I make homemade cayenne pepper sauce every year. I do add some liquid pectin to slightly thicken it so it will stick to food rather than roll off. After a month or so on the shelf it seems to separate a bit. What can I add to this so that it won't or is there a method I can do to stop this. We are slowly working our way into marketing this product down the line and this won't work for that reason. We are using a water bath canning method, vinegar based, no sugar added.


I'm in $9th$ class and I was wondering how to solve this problem. I only know how to prove that $0.1010010001\dots$ is irrattional.

We write all postive whole integers after the comma, how do we prove that this is an irrational number? ($0.1234567891011121314...$)


$$\lim_{n \to\infty }\sum_{k=0}^n {1 \over k!}=e$$ Which is the proof for the limit listed above?I know its a famous limit,but i cant figure out how to solve it(I'm a 12th grader).

I've been asked by some schoolmates why we have $$ \sum_{n=0}^\infty \frac{1}{n!}=e.$$ I couldn't say much besides that the $\Gamma$ function, analytic continuation of the factorial, is defined with an integral involving $e$. Then I also know that actually $$ \sum_{n=0}^\infty \frac{x^n}{n!}=e^x.$$ Is there a reason for these facts?  P.S. I added the tag "intuition", please remove it if you think it is not pertinent.


I have a alcatel pixi 3 (4.5) 5017x.  I would love ubuntu phone on it,  but that fails me,  I really tried everything,  Please help my,  grt gunter

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


Where can I download the 32-bit ISO of Ubuntu?

I would like to see a full how-to guide on how to install Ubuntu.


I was in creative and then I put an Enderdragon egg in the wrong place and I couldn't get rid of it. I kept punching it but nothing happened.

So I finally killed the Ender Dragon! As I was climbing the portal back to the world, I noticed that on top of the column there was an egg. So I attacked, mined, clicked and nothing happened, it just teleported away. What does the egg do and how do I get it?


A question was posted on site X, but it looks like it might be suitable on site Y.  How should moderators and close-voters decide whether to migrate it to site Y?  What criteria should be used?  This was a subject of a lengthy discussion among multiple site mods, and it became clear there is a broad range of opinions about this subject and apparently no definitive reference outlining an approach.  So, this is an attempt to create a reference question, in hopes that it generates answers that help outline possible ways to think about this.

I posted a question which was closed as off-topic and it seems like it could fit on another site in the network. How can I go about moving it there?   What is migration? When can a question be migrated, and who can migrate it? When should I consider migration, and when is it inappropriate? What causes a migration to be blocked and what happens after? What causes a migration to be rejected and what happens after? Anything else I should know about migration?


ASP.NET 4.0 has not been registered on the Web server. You must manually configure your Web site for ASP.NET 4.0 if you want your site to run correctly.  How can I fix this in Visual Studio 2012 on Windows 7.

When I start a new ASP.NET project in Visual Studio, I can create an ASP.NET Web Application or I can create an ASP.NET Web Site.  What is the difference between ASP.NET Web Application and ASP.NET Web Site? Why would I choose one over other?  Is the answer different based on which version of Visual Studio I am using?


The derivative of a function $y = f(x)$, $\frac{dy}{dx}$ seems to behave like a quotient in many cases:  $$ dy = \frac{dy}{dx} dx,$$  or  $$ u = h(x) $$ $$\int f(x) dx = \int h(f(x)) \frac{du}{dx} du$$  Yet we're often told that it's not correct to view it that way. For example, the wikipedia article on Leibniz' notation says  The expression dy/dx should not be read as the division of two quantities dx and dy.  Is there an example of a situation in which viewing $\frac{dy}{dx}$ as a quotient will lead to an incorrect result?

Background  I am a first year calculus student so I would prefer if answers remained in Layman's terms.  It is common knowledge and seems to me a mantra that I keep hearing over and over again to "not treat differentials/derivatives as fractions".  I am of course, in particular, referring to Leibniz notation.  However, aside from a quick response such as "oh, it's because its not a fraction but rather a type of operator", I never really got a full answer as to why we can't treat it as such. It just kind of sits at the edge of taboo in my mind where it sometimes gets used and sometimes doesn't.  Confusion is further compounded when a lot of things seem to just work out if we treat them just as fractions (e.g. u-substitution / related-rates)    Example     Air is being pumped into a balloon at a rate of $100cm^3/s$. We want the rate of change of radius when the radius is at $25cm$.   $$\text{we are given}\ \frac{dv}{dt}=100cm^3/s$$ $$\text{we want}\ \frac{dr}{dt}\ \text{when}\ r=25cm$$ Thus we will solve this by using the relation $v=\frac{4}{3}\pi r^3$ $$\frac{dv}{dt}=\frac{dv}{dr}\frac{dr}{dt}$$ $$\frac{dv}{dt}\frac{dr}{dv}=\frac{dr}{dt}$$ $$100\frac{1}{4\pi r^2}=\frac{1}{25\pi}$$ So the answer is $\frac{dr}{dt}=\frac{1}{25\pi}$ when $r=25cm$  *Note the manipulation of derivatives just as if they were common fractions using algebra.    Question  When exactly can I treat differentials/derivatives as fractions and when can I not?   Please keep in mind that at the end of the day, I am a first year college student. An answer that is easy to understand is preferred over one that is more mathematically rigorous but less friendly to a beginner such as me.


Reviewing , I hit Improve Edit and further updated the post.  Now the suggested edit is "orphaned".  It shows in :        but not in : (History for all users is shown. You need 10K to see it using the link.)         And  shows just the Community User:        when it should also show the reviewing user. For example:         So, how did this suggested edit get orphaned? I've seen this a few times now over the years.    PS: If it's not obvious, I am user Brock Adams on Stack Apps.

The day before yesterday I reviewed  in  (I have > 2K rep there).  I clicked on “Improve Edit”, made some more changes, and saved (submitted) them.  All the changes were made (both the ones “suggested” by  and mine), and  shows two revisions — #5, by Chema, and #6, by me — made at the exact same time.   The issue is that revision #5 is shown as having been reviewed by the Community user, with no indication that I did an Improve Edit:          unlike the normal way it looks when I improve an edit:         Also, I looked at my editing stats, and they were the same before and after:        [Scott has approved 1267 edit suggestions and rejected 750 edit suggestions and improved 289 edit suggestions] Normally the third number (improved ___ edit suggestions) would go up by one. Also, it does not appear in my Review history ( → “Activity” → “all actions” → “reviews”) or .   This happens on a recurring, but occasional (irregular, irreproducible), basis.  For example, see , , and .  I did “Reject and Edit” on all three, but I didn’t “get credit” for .


I have been refused UK visit visa 4 times. First time is 2015 Jan, they refuse visa because I applied wrong visa type and second time is 2015 Dec they refused again due to my bank statement.   Third time  May 2019, I am planning to go UK to attend my graduation but they refused again bank statement and economic social ties. And then I reapply again after 5days later, they refused again due to bank statement n they want to know originated fund as per photo.   If I explain all my financial details, do I have chance to approve it? Please advise me should I reapply again?   Thanks

Over the course of time here on TSE, I have observed individuals whose pattern of visa applications is best described as ''...     serial refusals - Two or more consecutive visa refusals issued by the same regime to the same person. Commonly for the same, or nearly the same, reasons. In some visa regimes Serial refusals can have a cumulative effect wherein the applicant's credibility is increasingly eroded, especially when the application pattern suggests a secondary agenda.   A common thread appears to be the need to visit the destination country (especially Schengen, the USA, or the UK) with a special sense of urgency. Also common in these cases are the following types of questions...   Should I just reapply once again? What are my chances? What can I do to improve my odds in the future? Can I somehow address the previous refusals to avoid them being a burden on all future applications? How can I break the pattern?      NB: This question is intended as a canonical about serial refusals. I have never been personally denied a visa.


As I understand it, then when I am standing on Earth I feel a force on my feet and is accelerated through spacetime. But what if a person is standing on the other side of Earth. That person is also accelerated. I kind of feel this is strange because it is in a different direction. But I guess it is because I am not allowed to look at it from the Earth frame? Or is it because I can´t use my own local frame to look at the other person?

I know this question has been asked in other forms, generally regarding the balance of forces.  This time I want to focus on motion.  I've got a laser accelerometer on my desk.  It tells me that I'm accelerating at $9.8~\rm m/s^2$.  For the first experiment I'm travelling in space.  I pick a nearby star and discover that I move about $490$ meters in $10$ seconds from that star.  For the next experiment I'm on the surface of Earth.  I measure the same acceleration with my laser accelerometer.  I pick a spot (the center of the Earth) and discover I don't move at all in $10$ seconds.  How is acceleration without motion possible?


Let $f: V \to W$ be a finite surjective morphism of varieties, with $W$ proper and normal. Does there exist a trace map $$ \operatorname{trace}\colon f_* \mathcal O_V \to \mathcal O_W? $$ I know that such a thing exists if $f$ is etalé, or (more generally) finite and flat. Does normality of $W$ help here? Lipman seems to assume the existence in his exposition Dualizing sheaves, differentials, and residues on algebraic varieties, but doesn't explain it further.  In general, if $A \subset B$ is a finite ring extension, there is a finite fileld extension $K \subset L$ of fraction fields, and a  $\operatorname{trace}: L \to K$. I guess one wants to restrict this to $B$ and hopes it ends up in $A$? I find it hard to find examples where $f$ is not finite and flat, but , $$\mathbb C[x^2, xy, y^2] \subset \mathbb C[x,y]$$ gives an example where $X$ is regular, $Y$ is normal, but $f$ is not flat. However, considering the extension of quotient fields $K \subset L$ one sees that $L = K(x)$, and $x$ has degree $2$. The trace mapping is then given by \begin{align*} \operatorname{trace}: L & \to K \\ 1 & \mapsto \operatorname{trace} \begin{pmatrix} 1 & 0 \\ 1 & 0 \end{pmatrix} = 2 \\ x & \mapsto \operatorname{trace}\begin{pmatrix} 0 & x^2 \\ 1 & 0 \end{pmatrix} = 0 \\ y & \mapsto \operatorname{trace}\begin{pmatrix} 0 & xy \\ \frac{xy}{x^2} & 0 \end{pmatrix} = 0. \end{align*} Since $\mathbb C[x,y]$ is generated by $x,y$ as a $\mathbb C[x^2, xy, y^2]$-module, we see indeed that the trace morphism descends to a morphism $$ \mathbb C[x,y] \to \mathbb C[x^2, xy, y^2].$$ Are there examples where the trace map does not descend?

I am trying to understand why if $f: Y \rightarrow X$ is a finite surjective morphism of normal (irreducible) complex varieties, there is a trace-map $f_{\ast} \mathcal{O}_Y \rightarrow \mathcal{O}_X$ splitting the natural inclusion in the other direction.   What I understand so far is (1) that the finiteness condition ensures that $f_{\ast} \mathcal{O}_Y$ is integral over $\mathcal{O}_X$, so $K(Y)$ is algebraic over $K(X)$ and (2) that there is a trace map from the algebraic closure $K(Y)$ to $K(X)$, which restricts since the extension is integral.  However these steps feel a little shakey to me, and also I haven't used normality. Is it just required for the extension of fields to be Galois (I guess it guarantees it will be a normal extension?) I don't quite understand this part.   For reference, I am trying to understand the proof of the Injectivity Lemma 4.1.14 in Lazarsfeld.   Thanks for your help.


I am trying to simulate a coin toss using R. For that I used both sample function and rbinom function. But I am getting different results. > set.seed(1) > rbinom(10,1,0.5)  [1] 0 0 1 1 0 1 1 1 1 0  > set.seed(1) > sample(c(0,1), 10, replace = TRUE)  [1] 0 1 0 0 1 0 0 0 1 1  What may be the reason for that? I thought for the same seed value, both sample function and rbinom should give the same result.

I'm trying to model a Roulette game where if you bet on red (out of red(18/37), black(18/37), green(1/37)) and if you the ball lands on red you win 1 dollar and if it doesn't you lose $1. So in this case, is it a binomial distribution? Since there are only 2 outcomes from the gamblers perspective, red or not red. If thats the case are these 2 R functions the same?  set.seed(3) sample(c(0,1),100,replace=T,prob=c(19/37,18/37))     rbinom(n = 100, size = 1, prob = 18/37)


I saw a video on youtube with link  ""  In the video a stream of water is run from a nozzle attached to a speaker diaphragm. The speaker plays a 24Hz sinusoidal tone, which is the same frequency as the shutter on the camera filming the video. With the speaker playing, the video appears to show the stream of water frozen in a zigzag or wave shape.   Is there someone kind enough to explain what is happening in the video I mean by science used.

A  posted on Youtube.  How does this phenomenon work? I know he is using frequency to propagate water in a sine/cosine wave, but how does it exactly work this way? Why do we see it as if its paused, or in slow motion, or even in reverse?  Can someone please explain this? I am intrigued by the video and want to know it's physics.


Proof.  Let $\sum_{k = 0}^N c_k \rightarrow s$, let $\sigma_N = (S_0 + \dots + S_{N-1})/N$ be the $Nth$ Cesaro sum where $S_K$ is the $Kth$ partial sum of the series.  Then $s - \sigma_N \\= s - c_0 - c_1(N-1)/N + c_2(N-2)N +\dots+c_{N-1}/N \\ =c_1/N + c_2 2/N + \dots + c_{N-1}(N-1)/N + c_N + \dots$  Where do I go from here?

I wanted to prove the following:  if $x_n \to x$ then $y_n \to x$ where $$ y_n = {x_1 + \dots + x_n \over n}$$  Please can you tell me if my proof is correct? My proof is this:  Let $\varepsilon > 0$. Fix $N$ such that $n > N$ implies $|x_n - x| < {\varepsilon \over 2}$.   Then $\left |{1 \over n} \sum_{k=N+1}^{N + n} x_k - x \right | < {\varepsilon \over 2}$. Now let $M$ be such that ${|x_1 + \dots + x_N | \over M} < {\varepsilon \over 2}$ and $M > N$. Then  $$ \left | \sum_{k=1}^M {x_k \over M} - x   \right | \le  \left | \sum_{k=1}^N {x_k \over M}   \right | +  \left | \sum_{k=N+1}^M {x_k \over |M-N|}  - x   \right | < \varepsilon $$ Here the proof is finished. But one can observe:  It is possible that $y_n$ converges even if $x_n$ doesn't: If $x_{2n} = 0$ and $x_{2n + 1} = 1$ then $x_n$ does not converge but $y_n \to {1 \over 2}$.


$$ \sum_{n=1}^\infty \frac{n!e^n}{n^n} $$ Where $e$ is Euler's number.  Recently on calculus class we were covering convergence tests and my group got stuck with this infinite series. Our calculus teacher told us that it diverges but he doesn't see any elementary way or simple test to prove it. He told us something about Euler's Gamma function and said that he knows it diverges because of Stirling's formula but this is not quite our level yet.  I tried to think about it myself but I established only that this  is some kind of an edge case. We could generalize the problem to series of $\frac{n!a^n}{n^n}$. Then, from the ratio test we know that it converges for $a <e$ and diverges for $a>e$. For $a=e$ the test is inconclusive. I've also tried to compare it with various divergent series, but nothing worked...  Does anybody have any idea for a simple solution?

I want to find the convergence interval of the infinite series $\sum\limits_{n=0}^\infty \dfrac{n!x^n}{n^n}$. I will use the ratio test: if I call $u_n = \dfrac{n!x^n}{n^n}$, the ratio test says that, if the following is true for some values of $x$, the series will be convergent for these values of $x$: $$\lim_{n\to+\infty}\left|\frac{u_{n+1}}{u_n}\right|<1$$ So, I will first calculate the value of $\left|\dfrac{u_{n+1}}{u_n}\right|$: $$\left|\dfrac{\dfrac{(n+1)!x^{n+1}}{(n+1)^{n+1}}}{\dfrac{n!x^n}{n^n}}\right|=\dfrac{(n+1)!|x|^{n+1}}{(n+1)^{n+1}}\times\dfrac{n^n}{n!|x|^n}=\frac{(n+1)n^n|x|}{(n+1)^{n+1}}=|x|\left(\frac{n}{n+1}\right)^n$$ So, $\lim\limits_{n\to+\infty}\left|\dfrac{u_{n+1}}{u_n}\right|$ becomes: $$\lim_{n\to+\infty}\left|\frac{u_{n+1}}{u_n}\right|=\lim_{n\to+\infty}|x|\left(\frac{n}{n+1}\right)^n=|x|\lim_{n\to+\infty}\left(\frac{n}{n+1}\right)^n$$ Now I must evaluate the value of $\lim\limits_{n\to+\infty}\left(\dfrac{n}{n+1}\right)^n$. For this, let $y = \left(\dfrac{n}{n+1}\right)^n$; so, instead of calculating $\lim\limits_{n\to+\infty}y$, I will first calculate $\lim\limits_{n\to+\infty}\ln y$: $$\lim_{n\to+\infty}\ln y=\lim_{n\to+\infty}\ln \left(\dfrac{n}{n+1}\right)^n=\lim_{n\to+\infty}n\ln\left(\frac{n}{n+1}\right) =\lim_{n\to+\infty}\frac{\ln\left(\frac{n}{n+1}\right)}{\frac{1}{n}}$$ Applying L'Hôpital's rule: $$\lim_{n\to+\infty}\frac{\ln\left(\frac{n}{n+1}\right)}{\frac{1}{n}} =\lim_{n\to+\infty}\frac{\frac{1}{n(n+1)}}{-\frac{1}{n^2}} =\lim_{n\to+\infty}\left(-\frac{n}{n+1}\right)=-1$$ Now, since we know that $\lim\limits_{n\to+\infty}\ln y = -1$, we have that: $$\lim_{n\to+\infty}y=\lim_{n\to+\infty}e^{\ln y} = e^{-1} = \frac{1}{e}$$. Substituting this back into the expression $\lim\limits_{n\to+\infty}\left|\frac{u_{n+1}}{u_n}\right| = |x|\lim\limits_{n\to+\infty}\left(\frac{n}{n+1}\right)^n$, we have that the limit of $\left|\dfrac{u_{n+1}}{u_n}\right|$ as $n\to+\infty$ is: $$\lim_{n\to+\infty}\left|\frac{u_{n+1}}{u_n}\right|=\frac{|x|}{e}$$ Therefore, the series will certainly be convergent for the values of $x$ for which $\dfrac{|x|}{e}<1$, that is, $|x|<e$. So, I know that the series is convergent for $-e < x < e$, but I have to test whether the series is convergent at $x = e$ or $x = -e$. That is, I have to test whether $\sum\limits_{n=0}^{\infty} \dfrac{n!e^n}{n^n}$ and $\sum\limits_{n=0}^{\infty} \dfrac{(-1)^nn!e^n}{n^n}$ are convergent. Since these limits don't approach zero, I know they are both divergent, but I'm not sure how to find the limits, because of the factorial function. Also, I can't use integral test here, because of the factorial. Probably I should use comparison test, but I haven't found any divergent series to which to compare it. Any hints? Thank you in advance.  Edit: Using the suggestion by Ragib Zaman in the answer below, since the Taylor polynomial $P_n(x)$ of $e^x$ at $a=0$ is $$e^x = 1 + x + \dfrac{x^2}{2!} + \cdots + \dfrac{x^n}{n!}+\cdots,$$ if we substitute $n$ for $x$ we see that $e^n>\dfrac{n^n}{n!}$; therefore, $\dfrac{n!e^n}{n^n} > 1$, and, thus, we show that $\sum\limits_{n=0}^{\infty} \dfrac{n!e^n}{n^n}$ is divergent, because its term doesn't approach zero. $\sum\limits_{n=0}^{\infty} \dfrac{(-1)^nn!e^n}{n^n}$ is also divergent, because, although the absolute value of the ratio between two successive terms, $|e|\left(\frac{n}{n+1}\right)^n$, approaches 1 as $n\to\infty$, it approaches 1 from values bigger than 1; therefore, the absolute value of a term is always greater than the absolute value of the previous term.


I just upgraded windows 7 to windows 10. It was looking fine and working good. But comparing to windows 7, it was accessing more bandwidth. I have only low data plan, but Windows 10 accessing more data.  In windows 7, I can disable automatic updates. That too windows 7 not consuming more data bandwidth. But I can't disable the updates in Windows 10.   So, Please anyone let me know how to stop windows 10 from unwanted bandwidth access, like auto update, automatic apps update and automatic driver updates...

We've upgraded some machines to Windows 10 and realized there were some updates which updated as required. However, I realized there was no option available to stop the download similar to that on Windows 7 and 8.1. The only way I could stop the download was to stop the Windows Update service.  My question is does anyone know of a way to stop auto updates or is stopping the service is the only solution?


I am trying to create dynamic input fields on button click for contact fields using $A.createComponent.  From the examples I find online I am able to create <ui:inputText/> components but when I use <force:inputField/> I am getting error in browser console.  DemoComp.cmp  <aura:component >     <aura:attribute name="contact" type="Contact" default="{ 'sobjectType': 'Contact', 'LastName': 'Satapathy' }"/>     <force:inputField aura:id="contactName" value="{!v.contact.AccountId}"/>     <lightning:button label="Adjust Width" onclick="{!c.editField}"/>      <div aura:id="fieldPopup"></div> </aura:component>  Working code for <ui:inputText>  ({     editField: function(component,event,helper) {          var contact = component.get("v.contact");         $A.createComponent(             "ui:inputText",             {                 "aura:id" : "123",                 "value": "hello world"             },             function(newButton, status, errorMessage){                 //Add the new button to the body array                 if (status === "SUCCESS") {                     var popup = component.find("fieldPopup");                     var body = popup.get("v.body");                     body.push(newButton);                     popup.set("v.body", body);                 }                 else if (status === "INCOMPLETE") {                     console.log("No response from server or client is offline.");                 }                 else if (status === "ERROR") {                     console.log("Error: " + errorMessage);                 }             }         );     } })  Failing <force:inputField>  ({     editField: function(component,event,helper) {         var contact = component.get("v.contact");         $A.createComponent(             "force:inputField",             {                 "aura:id" : "123",                 "value": contact.AccountId             },             function(newButton, status, errorMessage){                 //Add the new button to the body array                 if (status === "SUCCESS") {                     var popup = component.find("fieldPopup");                     var body = popup.get("v.body");                     body.push(newButton);                     popup.set("v.body", body);                 }                 else if (status === "INCOMPLETE") {                     console.log("No response from server or client is offline.");                 }                 else if (status === "ERROR") {                     console.log("Error: " + errorMessage);                 }             }         );     } })

With the release of Spring '16 there appear to be significant improvements to the force:inputField components especially for the lookup fields.  We are trying to use them in our application, but are having issues generating them dynamically. In our use case the user may define a set of fields that they want displayed for their form. This means we need to generate a list of inputs based on a dynamic set of fields.  Here is a statically defined example of how we can show the Custom_Acccount_Lookup__c field.  <aura:attribute name="contact" type="Contact" default="{ 'sobjectType': 'Contact' }"/> <force:inputField value="{!v.contact.Custom_Account_Lookup__c}"/>   However how can we generate this same code if the field we want displayed was user defined? The code below obviously doesn't work, but is it possible to achieve this some other way? We have also tried to generate the component in the controller but run into similar issues when passing in the value.  <aura:attribute name="contact" type="Contact" default="{ 'sobjectType': 'Contact' }"/> <aura:attribute name="fieldToShow" type="String" default="Custom_Account_Lookup__c"/>  <force:inputField value="{!v.contact[v.fieldToShow]}"/>   We are starting to suspect that there is some pre-processing of the component code before it renders. Upon code inspection the component actually generated is a force:inputLookup which is not one that we can create but apparently Salesforce uses to display the lookup field.


How can we find limit of the sequence $\dfrac{n!e^n}{n^n} $? I know its limit is infinity. First, I showed it is strictly increasing(by taking ratio of terms) and then showed it is not Cauchy sequence. I want to prove this by some other method, like comparing with other sequence. Can any one give some hint?

$\lim n^n/(e^nn!)=0$ using Stirling approximation it is obvious. But can we do it without using Stirling approximation.  Now series with terms $x^n n^n/n!$ has ROC $1/e$. What we can say about behaviour of power series at endpoints?


I was wondering if there is any way to see the total hard drive space used by any  program, after the installation has been completed?

When using apt-get install <package_name>, and there are dependencies that need to be downloaded, the terminal outputs names of additional packages and total size, and asks for confirmation before downloading.   But, when dependencies are satisfied and nothing but the named package needs to be downloaded there is no size output and no confirmation.  When using Synaptic, I can see the total size that new packages that will use after installation but no way to see the size that needs to be downloaded, except to go from package to package and use properties to see the compressed size.  I would like to know if there is a way to see the size of a package(s) in terminal and Synaptic prior to downloading and installing it/them?


Let $A\subset B$ be integral domains, and let $b\in B$ be a unit. I am trying to show that $A[b]\cap A[b^{-1}]$ is integral over A.  Let $x\in A[b]\cap A[b^{-1}]$. It suffices to show that $A[x]$ is a finite $A$-module.   $x\in A[b]\cap A[b^{-1}] \implies x = a_0 + a_1b+\cdots+a_nb^n = c_0+c_1b^{-1}+\cdots+c_mb^{-m}$. In particular, $$0=x-x=(a_0 + a_1b+\cdots+a_nb^n) - (c_0+c_1b^{-1}+\cdots+c_mb^{-m})=b^{-m}(a_0b^m+\cdots+a_nb^{n+m}-c_0b^m-\cdots-c_m).$$ Since $b$ is a unit in the integral domain $B$, we get atleast that $b$ is algebraic over $A$. I don't know how to proceed.

Let $A$ and $B$ be two commutative rings with a unit element, with $B$ subring of $A$. Suppose $x$ is an invertible element in $A$. Then prove that the intersection of the two rings $B[x] \cap B[x^{-1}]$ is integral over $B$, i.e., prove that for any $a \in B[x] \cap B[x^{-1}]$ there is a monic polynomial $f$ with coefficients in $B$ such that $f(a)=0$.


Supposing I want to measure 1-5A over a range of 1-40V on an ammeter, should I change the shunt resistor every time the voltage changes so that the voltage drop across the shunt resistor stays the same?  If yes, how do ammeters on lab bench power supplies work over a wide range of voltages?

I have the following ammeter:   The seller recommends 75mV 100A shunt be placed with it. I want to know what will happen if I change the voltage going through the shunt. Should I be changing the shunt as well to read amps correctly?   I want to build a 1-40V (or maybe 50V) adjustable DC power supply and use this ammeter to measure current. What the right value of shunt that I should use to get the right measurement? Changing shunts in a lab bench power supply is impractical, of course.  EDIT: I am planning to measure only up to 5A or so. Sorry I forgot to mention this previously.


I'm trying to use FFmpeg to convert a bunch of Png's into a gif, while setting the duration of each frame and while using an optimal palette (and other parameters, such as dither) on a single command.  I was reading , but the examples are using two commands and a temporary palette.png file.    Here's what I got, without using palettegen and paletteuse:  -vsync 2 -safe 0 -f concat -i "concat.txt" -y "example.gif"   The concat.txt file contains each frame path and duration, like:  file 'C:\0.png'   duration 0.066    It outputs a gif with a default palette as expected.    So, my question is how can I use palettegen and paletteuse on the same command, without a temporary file?

Following  I managed to create high quality gifs in reasonable memory size.  Using piping, what I'm currently doing is this  # Generate palette ffmpeg -y -i - -vf fps=15,scale=600:-1:flags=lanczos,palettegen some_dir/palette.png  # Generate gif using palette ffmpeg -y -i - -i some_dir/palette.png -filter_complex fps=15,scale=600:-1:flags=lanczos[x];[x][1:v]paletteuse output.gif    This is working great, but I read in the tutorial above that it is possible to generate a different palette for EVERY frame, how can I do that ? (Generate and use different palette for every frame)


A lady friend overseas at the moment, got robbed the other day. And asked for my acct info to make deposits into my acct and me withdraw them out and moneygram them back to her...is it safe?

A woman on Facebook recently contacted my dad.  She asked him to get a bank account so she could send him money, and he would send money to her employees (about 12 people), and she would pay him for doing so each time. She said the last person who she had do this for her ran away with all her money. But he would have made more money continuing to do this money transfer thing for her. I am not sure if this is a scam or not. Sounds weird to me, but my dad said it’s worth the try.  I had to get the bank account in my name because my dad has bad notices on his records for falling for fraud traps and asking for refunds too many times. She stressed to him that it had to be the bank “American Christian Credit Union;” for what reason, I’m not sure. There is no large amount of personal money in this bank account, just the minimum amount to open the account: $25.  I’m skeptical about this and confused as to why this person would send a large amount of money to a random person on the Internet?  Has anyone heard of any scams like this?  What should I look out for?


Here is my answer in python for generating all permutations of a list It's not giving me the correct solution, and I'm not sure where I went wrong. sol=[] def prem(A,lis=[]):   if len(A)==0:     print(A)     sol.append(lis)   else:     for index,elem in enumerate(A):       print(A)       prem(A.pop(index),lis.append(elem))

How do you generate all the permutations of a list in Python, independently of the type of elements in that list?  For example:  permutations([]) []  permutations([1]) [1]  permutations([1, 2]) [1, 2] [2, 1]  permutations([1, 2, 3]) [1, 2, 3] [1, 3, 2] [2, 1, 3] [2, 3, 1] [3, 1, 2] [3, 2, 1]


When I use the figure environment to set an image as a float in a separate page ([p] specifier), I want to be able to use up the full text height, so that the image and its caption are precisely alligned with text on the adjacent page. I want to have captions at the bottom. This means I need to set the image height to \textheight MINUS the height of the caption that comes after.  I am aware of question:  and the solution offered there works in continuous text, but not in the figure environment.  I was also made aware of question , which comes very close to what I need, except I think that having to set the number of lines in a caption manually is a little awkward, and I am looking for a completely automatic way of computing the caption height.

I have a figure with a 3 line caption. I would like to insert the figure as tall as possible. If I use  \includegraphics[height=\textheight]{file}   The figure is as high as the textblock and the caption is at the footnote position. Is it possible to set the height the figure, so the caption is aligned with the bottom of the textblock?


I need to take a lot of Products Pictures , I need to generate and adding at the same time that i trigger the photo a Bar Code with, is it posible? Please, teach me

I need a DSLR camera with a barcode scanner for on-site tours photography, which means it needs to be untethered! The image would have to contain the barcode scanned information in the image metadata or in the name itself.  I've seen solutions like, Foolography and a $2600 Canon Studio Edition launched in 2010. But I'm not sure of either those products!  So I'm asking the gurus here how I can get this working, which camera would I need and any accessory necessary?  I'm trying to recreate something like I saw the on-site volume photographers do in Disney's parks.


Context: 16.04  How does one mouse right-click action to compute the MD5 sum of a file?

Possible Duplicate:          I'm trying to make a Mark as executable command for the right click in nautilus for a faster work flow. I came up with this script:  #! /bin/bash for file in $NAUTILUS_SCRIPT_SELECTED_FILE_PATHS; do gksudo "chmod +x $file" & done   How do I get this to work though. I currently have a .sh file and have no idea where to put it.


I run Ubuntu from the USB drive, and select trial mode, because I do not want to install on the computer, just use it as a portable system on different computers that I have.  The problem I have, when I turn off the computer, all the settings I have selected and the applications I have installed are deleted, because they are saved in RAM rather than USB  I ask how can I do that they will be saved on the USB and will not be deleted  Would appreciate help,  Excuse me for using translation

I'd like to have Ubuntu installed on a USB stick, that I could plug in (almost) any computer and boot from it, and that I could use (almost) normally, as if it was installed on that computer. I'd also like to have a data partition on it that could be used by (almost) any computer, mostly to store some portable apps, just in case.    I've been told that if I installed Ubuntu in BIOS mode, I wouldn't be able to boot from a computer in UEFI mode, and vice versa.  Since I'd like to be able to boot on any computer, it's a big problem.  What can I do to be able to boot on computers in BIOS or UEFI modes in my case?  I've been searching for solutions but most of them are for specific needs that are different than mine, so it's difficult to extract the minimum requirements from those solutions to apply them to my problem.  Is there a simple, "clean" and quite generic solution to this problem?  I'd appreciate some explainations about the reasons why a specific solution is good or a specific step is needed.    My current setup:   USB stick:  OS: Xubuntu 16.04 i386 installation: full install (from a Live USB built with Rufus) drivers: none proprietary file systems:    partition table:    2: , /boot/efi, 128 Mio, FAT32, [boot,esp] 3: , 128 Mio, HFS+ 4: , 2 Mio, [bios_grub] 5: swap, 512 Mio 6: , /, 24 Gio, ext4, defaults,errors=remount-ro,lazytime,commit=60 1: , /media/data, ~3.6 Gio, FAT32, defaults,lazytime,check=strict  RAM:   /tmp, tmpfs, defaults,nosuid,nodev,noexec,mode=1777   swap:    vm.swappiness=5 swap partition: 512 Mio, for emergency zRAM swap files:    /var/swap/hib.swp: same size as RAM, for hibernation, generated by a script at startup /var/swap/opt.swp: if needed, generated by a script   overprovisioning: ~5.6%   built-in: ~1.2 Gio (apparently) added: 512 Mio  scheduler: deadline


I have AMD Graphics Card, which have model number Radeon HD 8450G. It is on a Notebook, HP PROBOOK 445 G1  My Ubuntu Installation worked good . It was a fresh install.  In the details tab of System Settings, Graphics driver is shown as "Unknown".

I am new to Linux/Ubuntu. I installed Ubuntu 11.10 on my Lenovo IdeaPad y510.   System info says    Graphics: unknown.   Driver: unknown,   Experience: Standard.   What should I do to use all my laptop hardware components to work properly with Ubuntu? Screenshot:


So I'm having a problem with what I believe to be a recent Windows 8.1 update (probably ). I use a vertical taskbar on the right side between two monitors. When I move my mouse across the split at a slow enough speed, the mouse ends up "sticking" to the current monitor. This catches me off guard several times a day at least and I find it intensely annoying. I haven't found any option to turn it off.  It also happens when the taskbar is on the left on the other monitor. It does not happen when there are no taskbars on that edge. It may also happen with a horizontal taskbar in a multimonitor layout with screens stacked vertically, but I haven't tested this.    Any ideas on how to disable this behavior?

In windows 8.1 and below, the mouse would seamlessly move through all my monitors.  However, in windows 8.1 update 1 the mouse needs to be going at a certain speed before it goes to a different monitor. How do I disable this?  A google search has turned up nothing, so I'm not sure what exactly is going on


Does anyone know how I can root my lg ms690. It is android version 2.2.1. Build # FRG83. Kernel version 2.6.32.9. SW version MS690ZV4. HW version 1.1. PRL verdion 3042. ERI version 1003. I have tried both zroot and gingerbreak, both with no success.

How can I root my LG Optimus M MS690 on Metro PCS? I've tried Gingerbreak, Superoneclick, and z4root without luck.


I am quite new to graphs (and could use some practice with math in general) and couldn't find a solution with zero intersections to this problem.  Assume you have two sets of 3 nodes (set H and set L) where each node (ex. h1, h2, h3) from one set should connect to every node on the other set (so l1, l2, l3). Is there any way you could arrange the connections so that there are no intersections?  Example of one edge intersection:

There's a puzzle where you have 3 houses and 3 utilities. You must draw lines so that each house is connected to all three utilities, but the lines cannot overlap. However, I'm fairly sure that the puzzle is impossible. How is this proved?


These questions must be at least 3-4 years old but it looks like someone is trying to spite me for some reason?  Is there any course of action I can take if someone is just following all my questions just to down vote them?

I just noticed that I lost a bunch of points from my reputation score, and I used the "reputation" tab on my user profile page to try and track down the cause.  During my investigation, I noticed there was an unusual event of type "reversal". In the normal place of a question title, it says "voting corrected".     What does this mean, and what caused it?  Did I do something wrong? Why did I lose all of that reputation? Is the system punishing me for leaving too many good answers?  Is there any way to earn it back?