After re-watching the movie, I realised that although Snape is revealed to be the 'Half-Blood Prince' - it is never explained as to how he got his name.   I assume 'Half-Blood' would be Half Muggle?   Anyone know the answer?
My question comes from what I learned in the movies, considering I have not yet been able to read the books. I would just like to know why Severus Snape called himself the Half-Blood Prince? Did many people call him that or did he just think that it was a cool nickname? This question might be answered in the books so feel free to quote from it.
Not getting edit's +2 rep after reaching 2k rep After reaching 2k rep , I'm not receiving  +2 rep per edit. Why? I'm trying to do some scenes which use a mixture of 3D backgrounds with 2D animated characters.The best way I've figured this out so far is to use a plane with an image sequence of pngs which hold the frames.  The problem with this method is Blender seams to only load image sequences based on image numbering. If I wanted to do a sequence which loops say, frames 0-5, then repeats 4-0 for the 'return' of the animation, I would have to load frames doubled up.  Is there a way, maybe with a script, to change the sequence order? I can see it as a useful plugin but my python skills are pretty much non existent. What caused the oathbreakers in the Paths of the Dead to turn into shades? In Return of the King, we are told that the shades who populate the Paths of the Dead are the spirits of oathbreakers who refused to aid Isildur in the first fight against Sauron.  First, we are told of the oath (Book 5, Chapter 2):     But the oath that they broke was to fight against Sauron... For at Erech there stands a stands yet a stone that was brought, it is said, from Númenor by Isildur... and upon it the King of the Mountains swore allegiance to him in the beginning of the realm of Gondor.   Then, when they fail to honor the oath, we are told about Isildur's curse on them:     "...this curse I lay upon thee and thy folk: to rest never until your oath is fulfilled."   And as we see in the following chapters, the Sleepless Dead are indeed subject to this curse exactly as Isildur descibed it. What seems less clear, however, is how Isildur's curse manages to alter the fundamental nature of the oathbreakers' mortality, so that they became undead shades instead of simply dying in disgrace.   Do we have any other examples of Isildur performing similar acts of magic? Based on what we are told in LotR, Isildur appears to have been a great warrior, but not a regular practitioner of magic. Is the stone at Erech somehow magically involved? (If so, do we know anything more about it or how it works? Does its origin in Númenor have any significance?) It is mentioned that the oathbreakers had worshiped Sauron; could this be a clue? I make heavy use of screen's "log" command to log the output of a session to a file, when I am making changes in a given environment. I searched through tmux's man page, but couldn't find an equivalent. Is anyone aware of a similar feature in tmux, or do I have to write my own wrapper scripts to do this?  EDIT: I'm aware of 'script' and other utilities that allow me to log a session. The reason that screen's functionality is so useful is the ability to define a logfile variable which uses string escapes to uniquely identify each session.  e.g. I have a shell function which, given a hostname, will SSH to that host in a new screen window and set the window title to the hostname. When I start a log of that session, it is prefixed with the window title.  If this functionality doesn't exist in tmux, I'll have to create a new set of shell functions to set up 'scripts' of sessions I want to log. This isn't hugely difficult, but it may not be worth the effort given that screen does exactly what I need already. Is there such a thing as a deposit-only bank account? My employer wants me to give my routing-numbers, social-security numbers, and basically everything else required to take money out of my account, to several third-party direct-deposit websites (one for weekly paychecks, one for mileage reimbursements, etc.).  I am not comfortable giving my identity information away to all these places.  I'd like to give them access to an account which they can only deposit into, never withdraw (either a separate account, or, even better, a deposit-only alias to my real account).  Does such a thing exist?    [Edit] I'm not worried about the companies so much as I am worried about bad guys who inevitably hack those companies' databases, or get hired to work there.  This type of account would also be handy for giving read-only access to sites like mint.com or quicken.com, easing my mind about their hackers/unscrupulous employees. Why XML-Serializable class need a parameterless constructor I'm writing code to do Xml serialization. With below function.  public static string SerializeToXml(object obj) {     XmlSerializer serializer = new XmlSerializer(obj.GetType());     using (StringWriter writer = new StringWriter())     {         serializer.Serialize(writer, obj);         return writer.ToString();     } }   If the argument is a instance of class without parameterless constructor, it will throw a exception.     Unhandled Exception:   System.InvalidOperationException:   CSharpConsole.Foo cannot be serialized   because it does not have a   parameterless constructor.    at   System.Xml.Serialization.TypeDesc.CheckSupported()   at   System.Xml.Serialization.TypeScope.GetTypeDesc(Type   type, MemberInfo sourc e, Boolean   directReference, Boolean throwOnError)   at   System.Xml.Serialization.ModelScope.GetTypeModel(Type   type, Boolean direct Reference)    at   System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(Type   type , XmlRootAttribute root, String   defaultNamespace)    at   System.Xml.Serialization.XmlSerializer..ctor(Type   type, String defaultName space)    at   System.Xml.Serialization.XmlSerializer..ctor(Type   type)   Why must there be a parameterless constructor in order to allow xml serialization to succeed?  EDIT: thanks for cfeduke's answer. The parameterless constructor can be private or internal. When should "into" be used rather than "in to," and vice versa? "Into" (one word) and "in to" (two words) are frequently confused.  In what situations should the former be used?  The latter? Windows 8 turns program sound volume down randomly I recently upgraded to Windows 8 from Win 7 64 bit and have started to encounter a strange issue. When I have any program running which plays sound, such as a game or spotify, after a random interval (usually around 5-10 minutes) the program sound will set itself really low.    If I Alt-Tab to the desktop and check the Mixer I can see that the Application volume has automatically set itself really low - the other volume levels (i.e. the Device speakers) stay the same.  I'm able to just set the application volume back to a reasonable level and it stays that way for another 5 - 10 minutes then goes quiet again.  My sound is Realtek High Definition Audio and my machine is an Acer Aspire 5738G if that helps in any way.  Any help much appreciated! Limits: How to evaluate $\lim\limits_{x\rightarrow \infty}\sqrt[n]{x^{n}+a_{n-1}x^{n-1}+\cdots+a_{0}}-x$ This is being asked in an effort to cut down on duplicates, see here: , and here: .    What methods can be used to evaluate the limit $$\lim_{x\rightarrow\infty} \sqrt[n]{x^{n}+a_{n-1}x^{n-1}+\cdots+a_{0}}-x.$$  In other words, if I am given a polynomial $P(x)=x^n + a_{n-1}x^{n-1} +\cdots +a_1 x+ a_0$, how would I find $$\lim_{x\rightarrow\infty} P(x)^{1/n}-x.$$  For example, how would I evaluate limits such as $$\lim_{x\rightarrow\infty} \sqrt{x^2 +x+1}-x$$ or $$\lim_{x\rightarrow\infty} \sqrt[5]{x^5 +x^3 +99x+101}-x.$$ How can I prove that $xy\leq x^2+y^2$? How can I prove that $xy\leq x^2+y^2$ for all $x,y\in\mathbb{R}$ ? How to calculate time difference in java? I know that there is a very similar question, but I'm not interested in highlighting. What I'm looking for is some tool in Linux to edit pdf files. I've tried pdfedit which did the work for me, but if freezes after a few edits. I've tried this tool under Ubuntu 9.10 and under KDE Fedora 14 and the same thing happens. I've tried Okular but the notations are too big to fill out exercises from pdf workbooks.    Is there any tool that suits this job? I don't care whether it is open source or I have to pay a reasonable price for it. Plotting several 2d functions in a 3d graph I am trying to reproduce a similar figure to the following one. My first guess was to use pgfplots but I didn't find any example that I could use as a starting point. At the moment I am unsure if pgfplots is actually the right package or I should rely on something else e.g. TikZ.   Since I don't really know where to start, I would appreciate any piece of code that points me in the right direction.    EDIT  Here is some dummy data for the plots.  plot1   plot2   plot3   plot4 0       0       0       0 3.466   2.058   0       0 4.262   2.976   0.001   0 3.822   3.168   0.006   0.008 2.953   2.936   0.019   0.063 2.065   2.492   0.046   0.265 1.332   1.977   0.092   0.734 0.797   1.478   0.164   1.508 0.443   1.045   0.268   2.44 0.228   0.698   0.412   3.219 0.107   0.438   0.598   3.524 0.046   0.256   0.831   3.219 0.017   0.138   1.109   2.44 0.006   0.067   1.429   1.508 0.002   0.029   1.78    0.734 0       0.01    2.141   0.265 0       0.003   2.479   0.063 0       0.001   2.736   0.008 0       0       2.808   0 0       0       2.465   0 0       0       0       0 Adobe Illustrator: strange behavior while aligning objects I know there are many ways to prevent image caching (such as via META tags), as well as a few nice tricks to ensure that the current version of an image is shown with every page load (such as image.jpg?x=timestamp), but is there any way to actually clear or replace an image in the browsers cache so that neither of the methods above are necessary?  As an example, lets say there are 100 images on a page and that these images are named "01.jpg", "02.jpg", "03.jpg", etc. If image "42.jpg" is replaced, is there any way to replace it in the cache so that "42.jpg" will automatically display the new image on successive page loads? I can't use the META tag method, because I need everuthing that ISN"T replaced to remain cached, and I can't use the timestamp method, because I don't want ALL of the images to be reloaded every time the page loads.  I've racked my brain and scoured the Internet for a way to do this (preferrably via javascript), but no luck. Any suggestions? Is it possible to make the default scene fill two monitors at startup? I know how to set up the default scene by pressing Ctrl+U, but whenever I startup Blender it always fills only one of my screens, even if I set it to fill both before setting the default scene. I end up having to resize it every time I start it up. Is there a way to set this to happen by default? How can I replace a string in a file(s)? Replacing strings in files based on certain search criteria is a very common task. How can I    replace string foo with bar in all files in the current directory? do the same recursively for sub directories? replace only if the file name matches another string? replace only if the string is found in a certain context? replace if the string is on a certain line number? replace multiple strings with the same replacement replace multiple strings with different replacements Grant admin rights on an application I'm want to grant a user administrative rights to one application on Windows 7. I don't want them to be able to have full admin rights, but admin rights are required for one of the applications they need to use.   Is there a way to set up a batch script or something where the user won't know it's being run as admin?  Or is there another way?  How can I accomplish this? Are there any non-green, non-artifact mana ramp cards? I have looked and can't seem to find any.  I have seen many green cards and some artifacts that do this, but nothing in Red, Blue, Black or White.    Are there any?  Note: By "Mana Ramp" I mean a card that generates mana, or one that lets you play more than one land per turn.  The end result, for example, would be on turn 4, playing a white only deck, I could tap more than 4 mana.  (Normally you only get one land per turn so a max of 4 mana on turn 4.) Using the itemize environment inside a caption The following code does not compile. However, if I remove the itemize environment it does. I googled for this problem, and found suggestions that using the caption package would solve the problem, though I did not find any clear description of why the problem occurred in the first place. See for example    I'm using Debian squeeze with TeX Live 2009-11. The included version of caption has   \ProvidesPackage{caption}[2009/10/09 v3.1k Customizing captions (AR)]   I also tried downloading and using the caption package from     but this doesn't change anything. I put the sty files in my current directory. I assume that overrides the system files. This one corresponds to  \ProvidesPackage{caption}[2010/01/09 v3.1m Customizing captions (AR)]   Error message and example file follow.  *******************************************     ERROR: Argument of \@caption has an extra }.  --- TeX said --- &lt;inserted text&gt;                  \par  l.13     }  --- HELP --- From the .log file...  I've run across a `}' that doesn't seem to match anything. For example, `\def\a#1{...}' and `\a}' would produce this error. If you simply proceed now, the `\par' that I've just inserted will cause me to report a runaway argument that might be the root of the problem. But if your `}' was spurious, just type `2' and it will go away. ******************************************************  \documentclass{article} \usepackage{caption} \begin{document}  \begin{figure}     \captionsetup{singlelinecheck=off}     \caption     {       foo       \begin{itemize}       \item bar       \end{itemize}     } \end{figure} \end{document}