Grub dont shows after windows 8.1 update
How can I repair grub? (How to get Ubuntu back after installing Windows?)
At what age is the Force detectable in children? Java Generics: Generic type defined as return type only I'm looking at some GXT code for GWT and I ran across this use of Generics that I can't find another example of in the Java tutorials. The class name is  if you want to look at all of the code.  Here are the important parts:  private RpcMap map;  public &lt;X&gt; X get(String property) {   if (allowNestedValues &amp;&amp; NestedModelUtil.isNestedProperty(property)) {     return (X)NestedModelUtil.getNestedValue(this, property);   }   return map == null ? null : (X) map.get(property); }   X is defined nowhere else in the class or anywhere in the hierarchy, and when I hit "go to declaration" in eclipse it just goes to the &lt;X&gt; in the public method signature.  I've tried to call this method with the following two examples to see what happens:  public Date getExpiredate() {     return  get("expiredate"); }  public String getSubject() {     return  get("subject"); }   They compile and show no errors or warnings.  I would think at the very least I would have to do a cast to get this to work.  Does this mean that Generics allow a magic return value that can be anything and will just blow up at runtime?  This seems counter to what generics are supposed to do.  Can anyone explain this to me and possibly give me a link to some documentation that explains this a little better?  I've went through Sun's 23 page pdf on generics and every example of a return value is defined either at the class level or is in one of the parameters passed in. What is the purpose of the Assemblies node in Web.Config? When creating a new ASP.NET AJAX Web Application in Visual Studio 2005, the default web.config contains the following section (inside the compilation node):  &lt;assemblies&gt;     &lt;add assembly="System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/&gt; &lt;/assemblies&gt;   Whether or not the assemblies node exists doesn't seem to affect the AJAX functionality.  Update panels, etc work fine regardless of whether or not the reference to System.Web.Extensions is included in Web.Config.  What's the purpose of this section, and can it be safely removed? I own a Nikon D40X and just the kit lens and I'm considering buying either a macro lens or some extension tubes.  I don't necessarily want to do true 1:1 macro, just some close ups of bugs, fungi and flowers. hotel occupancy counting problem The multiple-choice question:  A hotel has four vacant rooms. Each room can accommodate a maximum of four people. In how many different ways can six people be accommodated in the four rooms? (A) 4020 (B) 4068 (C) 4080 (D) 4096.  My attempt:  If there were no 'four person' constraint, the six people could be accommodated in $4^6=4096$ ways. however, this number includes combinations with 5 or 6 people in one room, which should be excluded.  If one room has 5 occupants, one other room has 1 occupant. The number of '1,5' combinations is ${{4} \choose {2}}$=12. If one room has 6 occupants, the other three rooms have no occupants, and there are four such combinations.  I believe the answer should be $4096-12-4=4080$, but am not confident. I'd be grateful for any comments on my attempt. I have 2 partitions (Windows and Ubuntu 13.04) and I am asked which one to boot each time I turn on my computer.  I want to install Ubuntu 13.10 to the entire disk.  I do not mind if all previous Ubuntu/Win data are lost.  How can I do that? It is usually said that existence of discrete spacetime violates Lorentz symmetry. What quantity is used to quantify such violation? I mean could someone points a reference for a derivation that shows such analysis.  My other question is: if Lorentz symmetry is violated, does that imply space-time is discrete? or not necessarily?) Limit of $\lim_{n\rightarrow \infty} \sum^{n}_{i=1} \frac{1}{\sqrt {n^2 +i} }$ How to draw density estimate on histogram by pgfplots? I know how to draw a density histogram using pgfplots from this answer: .  But how can I draw an estimate line on the histogram like this?    \documentclass{article} \usepackage{pgfplots} \begin{document} \pgfplotsset{     small,     every axis plot post/.style={         fill=orange!75,         draw=orange!50!black     },     trim axis left }  \begin{tikzpicture} \begin{axis}[ymin=0, title=\texttt{hist=density}] \addplot [hist=density] table [y index=0] {random.txt}; \end{axis} \end{tikzpicture} \end{document} Is it possible to prevent DHCP service on SBS 2003 from shutting down due to rogue DHCP server? $[K(\zeta_n):K]=\phi(n)$? Is it true that $[K(\zeta_n):K]=\phi(n)$ where $\zeta_n$ be primitive root of unity and K be field of char zero?  I think it should be equal to the degree of cyclotomic polynomial which has degree $\phi(n)$.  Can someone please elaborate that what is the procedure for finite fields I tried to change network interfaces name on this new Ubuntu 16.04 LTS version but doesn't have the /etc/udev/rules.d/70-persistent-net.rules.  So, I tried to use /lib/udev/write_net_rules but it not exist.  Why do I need this modification? Because I'm using a tool to Simulate virtual platforms that use flex licensing and the authentication need to be in eth0 interface name.  Any suggestion?  The command ip link returns:  user@laptop:~$ ip link  1: lo: &lt;LOOPBACK,UP,LOWER_UP&gt; mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: enp6s0: &lt;NO-CARRIER,BROADCAST,MULTICAST,UP&gt; mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT group default qlen 1000 link/ether b8:2a:xx:yy:xx:yy brd ff:ff:ff:ff:ff:ff 3: wlp7s0: &lt;BROADCAST,MULTICAST,UP,LOWER_UP&gt; mtu 1500 qdisc mq state UP mode DORMANT group default qlen 1000 link/ether 5c:e0:xx:yy:xx:yy brd ff:ff:ff:ff:ff:ff  user@laptop:~$ ifconfig  enp6s0    Link encap:Ethernet  HWaddr b8:2a:xx:yy:xx:yy   lo        Link encap:Local Loopback   wlp7s0    Link encap:Ethernet  HWaddr 5c:e0:xx:yy:xx:yy     (Some information were ignored and suppressed)  I already tried some links: What is the relationship between Guide Number and flash power level? From this , I understand that the flash guide number (GN) is given by the following formula:  Guide Number = Shooting Distance × f-number ÷ ISO factor   I'm assuming that the GN calculated via the equation above will be based on a flash that is firing at full power. Am I correct to assume that if I set the flash to fire at half power, that the guide number is effectively halved? i.e. the equation will now be:  Guide Number = Shooting Distance × f-number ÷ ISO factor * Power Level   where power level can be the following 1, 1/2, 1/4, 1/8, ... 1/64, etc? When a PHP application makes a database connection it of course generally needs to pass a login and password. If I'm using a single, minimum-permission login for my application, then the PHP needs to know that login and password somewhere. What is the best way to secure that password? It seems like just writing it in the PHP code isn't a good idea. Spoilers for the end of the second film      Towards the end of the fight against Ego, we see that the bomb Groot set off blows up Ego's core. Shortly thereafter, it cuts to a scene where Quill is shown apparently losing his powers.   Given that the movie builds up this finale so much, I'm left wondering:      Did Quill lose his powers or merely the means to access them after Ego's apparent death?   Answers from the film or comics are very much welcome. What's the difference between X = X++; vs X++;? Have you ever tried this before?  static void Main(string[] args) {     int x = 10;     x = x++;     Console.WriteLine(x); }   Output: 10.  but for   static void Main(string[] args) {     int x = 10;     x++;     Console.WriteLine(x); }   Output: 11.  Could anyone explain why this? Sum of two squares modulo p Why doesn't a bike/bicycle fall if going with a high speed? Why does a bike/bicycle fall when its speed is very low or close to zero and is balanced when going with a high speed? Explicit construction of a finite field with $p^n$ elements How can I pin a program to the Windows 7 Taskbar, with parameters?