Can someone explain the concept of  in an intuitive manner? I can't seem to understand this concept. I hope someone can explain this concept in an intuitive manner.
Negative probabilities are naturally found in the Wigner function (both the original and its discrete variants), the Klein paradox (where it is an artifact of using a one-particle theory) and the Klein-Gordon equation.  Is a general treatment of such quasi-probability distributions, besides naively using 'legit' probabilistic formulas? For example, is there a theory saying which measurements are allowed, so to screen negative probabilities? Additionally, is there an intuition behind negative probabilities?
I want to include something in my LaTeX article that will make all mathematical formulae appear in black, while all text (including everything inside \text{}s in the middle of mathematical formulae) appear in red.  Ideally I would like this to be something I could include in the preamble or in a .cls file or something like that.  What would be the quickest way to do that? A girl who transcends time I remember quite a bit, but can't seem to find the title or (female) author.   A girl accompanies her father as he captains a mission to travel at near-light speed in order to experience the effects of time dilation and return to Earth 100 years into its future. She leaves behind her boyfriend (Tal or Tel or something), who promises he'll find a way to stay with her despite the time travel that will render him, well, dead before her return. She's accompanied by a close friend who is deaf but lip-reads and speaks so well as to occasionally fool others into believing she is hearing. They spend a lot of time in the ship's garden. I believe he ends up either getting on a different ship to survive into the future via time dilation, or else having himself frozen. Either way, if I recall correctly, Earth isn't doing well at all by the time the mission with the girl returns. There's been a war or some other disaster. There's an extended period of vague, ambiguous, existential crap in which the girl (now a woman) eventually ends up transferring her consciousness into her own daughter, presumably in order to go on living. Everything wraps up somehow and the girl and her boyfriend walk together hand in hand on a desolate planet into the sunset near the end of time.   It was all really rather trashy and silly, I remember, and took itself entirely way too seriously, but I'd like to at least know what it was so I could read it again. Either it'll be worth a laugh, or it'll turn out to be surprisingly good. Why can't Python's raw string literals end with a single backslash? Technically, any odd number of backslashes, as described in .  &gt;&gt;&gt; r'\'   File "&lt;stdin&gt;", line 1     r'\'        ^ SyntaxError: EOL while scanning string literal &gt;&gt;&gt; r'\\' '\\\\' &gt;&gt;&gt; r'\\\'   File "&lt;stdin&gt;", line 1     r'\\\'          ^ SyntaxError: EOL while scanning string literal   It seems like the parser could just treat backslashes in raw strings as regular characters (isn't that what raw strings are all about?), but I'm probably missing something obvious. Vim inoremap for specific filetypes How do I get a consistent byte representation of strings in C# without manually specifying an encoding? No chatoutput in tellraw onClick Event I'm using a /tellraw command to display some kind of menu to the player. How can I react to the clickEvent without posting something in the chat? When I try using the scoreboard, I get an output in my chat like this Set score of &lt;objective&gt; for player &lt;playername&gt; to &lt;value&gt;. The same thing happens, when trying /setblock, /entitydata or /trigger Is there any way, I can execute a command which commandblocks can detect without writing a success/fail message in the chat?  the only commands without a "real" response message I found were /say, /tell and /tellraw. But all of these are impossible to detect(also, they write something else in the chat). JavaScript adding decimal numbers issue Object glitching/dissapearing in render due to parenting problems I have completed my animation but I realised when I render it that one of the propellers blades starts to glitch. On some frames it is in shot and some it is out of shot and this is really strange. These 'blades' are both parented to the same 'propeller' and the 'propeller' is parented to the middle ball. I have baked the animation through so this shouldn't be a problem. These propellers are passive rigid bodies. I have tried to figure out this problem and I just can't get to a solution. I've never had it where a rigid body object glitches out like that in the rendered animation, it's almost like it's jumping, which on the render these frames show the object as invisible. The video attached will show.   If anyone has experienced problems like this or knows an answer to my dilemma that would be greatly appreciated, thanks! How to I deal with unwrapped UVs orientation?   Delete the default Cube. Add a Cylinder Edit mode and edge select the Top and the Bottom and a single connecting edge. Make them into seams UV Unwrap (standard Unwrap mode)   The unwrapped UV now shows two circles above a row of quads. I can save this and open it in an image editor and paint over those areas and get the texture to align on the cylinder back in blender.  But, the pattern(just happens to be text) that was inserted in place of the row of quads is now upside down on the model. Any attempt to flip or align just makes things worse, from upside down to mirrored or the Top/Bottom not aligning.  So my real question is how could I have known that the quads represented an upside down view of the world?  Do other blender users export UVs and mark them with arrows and colours just to see how they align on a model before actually painting for real?  I tried selecting the edges in step 3 in different orders before making them into seams and it made no difference.  I also looked at the Normals but they appear to be only Inside/Outside not Up/Down.  Blender 2.70 Why can't I pass the table name to a prepared PDO statement?  $stmt = $dbh-&gt;prepare('SELECT * FROM :table WHERE 1'); if ($stmt-&gt;execute(array(':table' =&gt; 'users'))) {     var_dump($stmt-&gt;fetchAll()); }   Is there another safe way to insert a table name into a SQL query? With safe, I mean that I don't want to do  $sql = "SELECT * FROM $table WHERE 1" I am having a problem with permissions on a Linux server. I am used to BSD. When a directory is owned by a group the user who owns it isn't in such as www-data, files created in it will be owned by that group. This is important because I want files to be readable by the webserver (which I will not run as root) but so a user can still put new files in the directory. I can't put the users in www-data because then they can read every other users websites.   I want the webserver to read all websites, I want users to be able to change their own.  The permissions are set like this on the folders at the moment....  drwxr-x--- 3 john www-data 4096 Feb 17 21:27 john   It is standard behavior on BSD for permissions to work this way. How do I get Linux to do this? Disable the guest user completely in El Capitan without having to disable 'Find My Mac' I know it should be straight forward but unfortunately, it  isn't.  I did disable the guest user in the System Preferences by unchecking the checkbox for Allow guests to login in to this computer, but it still shows up on the login screen.  I have heard that disabling 'Find My Mac' would fix it for OS X Lion, but I want to keep it.  Is there a way to do this? This is tricky. I would like to install Ubuntu on a machine that is intended to work as server, and for some reason I do not have an option to connect a screen to it.  I expect this may be similar to remote installation. However, there is currently no OS on that machine, so I will have to set up everything from scratch.  On the other hand, I do have a physical access to that machine. Therefore I can get it to boot from a CD/USB. But that's not enough.  Is there a way to do such installation remotely? Is there a version of Ubuntu image that comes with a SSH server preinstalled, and starts it once booted, so that I can boot the machine with such image, connect to it via SSH and process the installation from a different computer?  If not, what other options do I have? Encode multi-class response variable In a classification problem when the response variable has multi-class, e.g., "sunny","rainy","cloudy", how should we encode it? I know that for predictors like this, usually we do , and if a predictors have too many classes, then we might just use the .   When this multi-class issue occurs in the response variable, I guess we can just use LabelEncode() rather use using One Hot encoding right? Because if we use One Hot encoding, then we will have 2 variables as the response variable, and the machine learning algorithm in sklearn usually expects the response variable not to be a vector right? (I mean it expects a long 1D vector with length equal to the number of observations but not a 2D matrix). But on the other hand, if we just map "sunny", "rainy","cloudy" to {1,2,3} or {0,1,2}, or whatever 3 numbers, that will create a less than or greater than relationship among "sunny", "rainy","cloudy", which is not inherited in the original problem. Can't select and delete an object "Where" in careers' search seems to be broken Let's say I want to find a company in Ontario, Canada. Ok, I navigate to company pages and type ON, Canada to Where in search:        but there are no companies in there. So why if I type just Canada it finds companies in ontario; and if I type specific area (ON, CA)  it doesn't find anything ? How to stream a video with VLC in a LAN Is $\mathbb{Z}[\sqrt{-7}]$ a UFD or not? Is $\mathbb{Z}[\sqrt{-7}]$ a UFD or not? I feel like there should be some easy example showing that it is not, but I can not think of one. I'm well aware of the combinatorial variant of the proof, i.e. noting that each formula is a different representation for the number of subsets of a set of $n$ elements. I'm curious if there's a series of algebraic manipulations that can lead from $\sum\limits_{i=0}^n \binom{n}{i}$ to $2^n$. What algorithm(s) are used by MoleculeModify's GenerateConformers?