I just made a  to flag a "thank you" answer. But this is what I got when I clicked "flag":    This is a brand new account. What happened?  Update: this issue also occurred on Physics SE. It hasn't affected Stack Overflow or Lifehacks SE.
I spotted a  (10k-only by now) and when I went to flag it, the flag dialog told me that I'd already flagged it as VLQ:    The thing is, I'd never seen this post before. And a look at the flag history in my user profile confirms that I haven't flagged a post since yesterday:    Certainly, well before the 2015-02-04 05:36:21Z time of Mr. Miracle's post.  I was able to reproduce this on SO from the VLQ review queue: when you're presented with an answer, click on link at the right side of the page, then click flag. You get the "you have already raised this type of flag" message on either the "it is not an answer" or "it is very low quality" options, I gather depending on the original flag that pushed the post into the VLQ queue.
Edit Mode Transparent Objects I changed my Blender Units to Metric System, but when I'm building things, my meshes are transparent, i.e. I can see through faces like in wireframe even though my wireframe is turned off. All faces have a light white in non-wireframe mode, but I can still see through them.   How do I reverse this?  Another issue I get is this    Looks like clipping is not working properly. What would be the associated wavelength of the particle if its velocity is zero? What happens when yellow light is passed through a prism? What happens when secondary colors like yellow,green and magenta are passed through a prism? Will it split into its component colors(for example yellow split into green and red)?If yes why we are observing secondary colors in the visible spectrum obtained when white light(composite light) is passed through a prism? How can I get a DisplayLink USB monitor work under Ubuntu? I have a DisplayLink-based external USB monitor, which has both power and data over USB, and seems to work perfectly under Windows 7, but only can display a text console under Ubuntu 10.10, and that I can only use when I am actually switched to it. So the only Use I can have so far is to have some text-based monitoring or console that I can watch while working on the graphic display.   I know there are some development done for DisplayLink, but I never could get it to actually run properly.   Yes, I tried the detailed setup described in other , but they did not work, and instead crashed my X that I had to restore.   Merci :-) 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. Android 4.1 (Jelly Bean) was announced at Google I|O 2012 on June 27, 2012.  (You can review  at the official Android Developer's site.)  Of course, not all devices will get this update right away and others won't get it at all. Each manufacturer and carrier often choose to add their custom modifications which tend to delay the official release.  When will each device get Android 4.1, either officially or unofficially, if ever?  See also: I use a Canon EOS Rebel T3i (600D) with the kit lens. I have experimented a lot with different settings and modes, but I feel like I have wasted many good shots that could have looked amazing, if only they were a little bit sharper.  I use auto-focus on most of my pictures and make sure to choose the right focus point, but all of my photos are still a little bit out of focus. When I zoom in, I can see that the pixels are not very crisp or well-aligned.  I am not sure if this issue is caused by my equipment or skills. Proof of inequality using AM-GM inequality prove that $x^2 + y^2 + z^2 \ge xy + xz + yz$  I tried proving it the way I prove $x^2 + y^2 \ge 2xy$. But it just doesn't seem to work. I tried using AM-GM. Should I be using GM-HM or AM-HM? I really don't know what the problem is and I'd appreciate any help and a full proof explanation. Thanks. I thought it was by Heinlein or Brown, but if it was I can't locate it online.    The plot was aboard a spaceship, or maybe a space station, when an accident sends the astronauts spinning out of control towards certain doom.  One part of the story I remember distinctly was the one of the guys started screaming inconsolably and the noise was driving everyone crazy.  One of the astronauts made his way over to the guy and smashed his helmet so the screaming stopped.  As I recall, the story ends with the narrator turning off his comm link so he can ponder the beauty of the universe in silence.  Sound familiar to anyone? Two friends who have unpredictable lunch hours agree to meet for lunch at their favorite restaurant whenever possible. Neither wishes to eat alone and each dislikes waiting for the other, so they agree that each will arrive at a random time between noon and 1 pm, and each will wait for the other for 15 minutes or until 1:00. What is the probability that the friends will meet for lunch on a given day? Fitting a plane to a set of points in 3D using PCA I am trying to estimate a midplane of a 3D model using the midpoints of paired landmarks, in order to reconstruct missing data (midplane refers here to the middle/saggital plane of the cranium which cuts the skull into two symmetrical halves, left and right).  I therefore need to estimate a plane from 27 points in 3D. I need to get the equation of the plane as $$ax+by+cz=d.$$  I have looked into orthogonal regression and principal component analysis (PCA) as methods, however I didn't take maths past A-levels and am struggling. I know I can supposedly use the eigenvectors to get the equation of the plane of best fit, but need someone to explain exactly how. I am using R for the PCA but am not great at R either.  Alternatively, if there's a better way to estimate the plane I would be glad to hear it! Probability that 2 appears at an earlier position than any other even number in a permutation of 1-20 Suppose we uniformly and randomly select a permutation from the 20! Permutations of 1,2,3,...,20. What is the probability that 2 appears at an earlier position than any other even number in the selected permutation?  My approach :   2 in first position ==> 1*19! (1 is the position of 2)  2 in second position ==> 10 *1 *18!  2 in third position ==> 10*9 *1 *17!  . . .  2 in 11th position ==> 10*9*8*7*6*5*4*3*2*1*1*9!  But this was asked as a multiple choice question in GATE 2007 and the options were  (A) 1/2   (B) 1/10  (C) 9!/20!  (D) None of these  I am not able to reduce this analysis to a given option. How to use an item in my off-hand? Does DTIME(O(n)) = REGULAR? Find all natural numbers $n &gt; 1$ and $m &gt; 1$ such that $1!3!5!\cdots(2n - 1)! = m!$   I have been thinking about coming up with some inequalities which would narrow the possible range of pairs $(n, m)$, however the best I have been able to find so far are $m \ge 2n - 1$ and $m \lt n^2$, which is clearly not enough.  Update. The question has tag combinatorics as it is from a book about combinatorics, so there must be at least partly combinatorial solution. Seeking open raw LiDAR or laser scanner data? How do volume control headphones work? A recent question over on  got me to wondering how volume control headphones work.  I don't mean volume control which works by , but the kind of volume control that signals to the device to increase or decrease the signal output.  For instance, according to the , the volume controls are only for apple devices:     Universal Compatibility and Microphone Communication   LP comes with 2 cables for universal compatibility with all modern mobile and audio devices. The 3-Button remote microphone cable is designed for the latest Apple devices, including iPhone®,iPad®, iPod®, and Macbook series. The long audio-only cable and 1/4" adapter is universally compatible with all audio devices and professional equipment.   However this sort of device apparently works with some android phones and the question implies that it works with some computer sound cards on Windows machines too, but not being an Apple buyer (and only recently getting my first smartphone) I haven't seen this sort of thing before. I've done a quick google search, but can't find anything on standards for this technology.   How does this work?   Is it something as simple as shorting left/right/mic channels? If so, could using headphones of this type with equipment that doesn't support this technology, damage that equipment? Is it a serial signal, for instance sent over the mic channel? Does it just require a headphone  connector or a headphone  +microphone TRRS connector?   Does this technique have a name?  Incidentally, is someone could answer this, I can probably look up the rest of the information myself. *8') Is it as standard as it appears, or is everyone just following Apple? Is this something that is patented?   If so, who holds the patent and do they charge a license fee for people to use this technology? If not, is there an open standard for it?    There is some excellent information in  to the question  but it doesn't answer the specifics of how this type of volume (etc.) control works, since it now seems to be rather more common and standard. Android Min SDK Version vs. Target SDK Version Given $f(x) = \frac{1}{2}x^TAx + b^Tx + \alpha $   where A is an nxn symmetric matrix, b is an n-dimensional vector, and alpha a scalar. Show that  $\bigtriangledown _{x}f(x) = Ax + b$   and  $H = \bigtriangledown ^{2}_{x}f(x) = A$   Is this simply a matter of taking a derivative with respect to X, how would you attack this one? So, after a few sessions, the new player I'd invited has been a bit of a disaster. He doesn't get on well with any of the other players, laughed when someone's character died (in our campaign that's permanent at the moment), and generally has been a nuisance. However, he doesn't seem to notice this. I've talked to him about his behaviour, but it hasn't helped. Several other players have also approached me on their own to register concerns.  The long and short of it is, he's not a good fit for our game or social group, due to his abrasive personality/playstyle (as I and the other players perceive it). He's also not interested in roleplaying (something my group does heavily, at the moment) and continually pushes to place himself in the limelight - which he does by instigating combat and trying to skip over what he sees as 'boring' scenes. His character is a Minotaur barbarian, and the most exotic race in the game, but he only uses it for the stat bonuses, and doesn't even have a backstory - he simply says he doesn't need one. However, I don't want to be rude or otherwise unkind to him, as I will still see him around after he leaves the group, and so will the other players.  How can I politely ask him to leave the group, without being dishonest but avoiding embarrassment for anyone? I also want to avoid seeming to 'abandon' him, or 'go behind his back'.  Note: There are few/no in-game problems with adding or removing characters, and I don't need advice for that. This is strictly about handling the player. The system (not that it's all that relevant to the problem) is