I just noticed that I'm not logged in on askubuntu.com and here's my login page:    What do I click to just use my connected StackExchange account?
don't really understand how to log on with your SE account in the new logon screen.  And although it might be obvious to most of us, some people find the new dialog hard to understand.        Can we add a logo and some text to make clear users can log on with their SE account? Something like:     [SE LOGO] Log on using your StackExchange account   Followed by the two boxes for email and password.
How can I create a new extensible symbol? Given an arbitrary thin vertical symbol, can I create a new math delimiter from it (and if so, how)?   Edit: Ideally, I would like to be able to create an extensible symbol, either built out an existing normal symbol, or even made from scratch.  Edit 2: I am pretty sure that what I am after is an explanation of how to create a .tfm file for an extensible symbol (which Werner's answer describes the general structure of, but not how to make one).    For example, let's say I wanted to use the \dagger () or \wr () symbol as a delimiter, and write expressions like    \[\left\ldagger \sum_{n=1}^\infty a_n \right\rdagger\]   where the symbol scaled appropriately. Would there be any distinction between declaring a symmetric delimiter (like \vert), as opposed to one that has inherently different "left" and "right" versions like [ and ]?  Now, even being unaware of the inner workings of TeX, I imagine that there has to be lots of information in the fonts for how a delimiter is to be scaled in different situations, and if I try to make my own delimiter, this information won't be present. Would I need to get deep into FontForge or equivalent to achieve my custom delimiters, or is there an easier way? How do I execute a string containing Python code in Python? I have two partitions that I want to mount on startup: /dev/sda3   /mnt/devel  ext4    defaults    0   2 /dev/sda2   /mnt/excess ntfs    defaults    0   2  The ext4 partition mounts fine (owned by me, writable only by me), but the NTFS mounts owned by root with R\W permission for all. How to fix this? drwxr-xr-x  7 amanda amanda 4096 2012-03-14 19:07 devel drwxrwxrwx  1 root   root   4096 2012-03-14 22:38 excess Why do microcontrollers have so little RAM? Maybe this is more of a perceptional problem, but it seems like microcontrollers have advanced by leaps and bounds in the last 20 years, in almost all regards, higher clock speed, more peripherals, easier debugging, 32-bit cores, etc...  It is still common to see RAM in the 10's of KB (16/32&nbsp;KB).  It doesn't seem like it could be an issue of cost or size directly. Is it an issue of complexity with the RAM controller above some threshold?  Or is it just that it isn't generally required?  Looking over a parts matrix at a popular Internet supplier, I see one  with 256&nbsp;KB for less than US$8, and then for a few dollars more you can find a few more that are ROMless, but it seems pretty sparse...  I don't exactly have a need for a microcontroller with a MB of volatile storage, but it seems like somebody might... I'm creating a composite image, in order to create a timeseries. I've already created the composited image, but i am having difficulty masking the clouds of the composite image. I've followed the code from a page having similar problems, however when I run the code (after replacing all the l8_mayo to composite as that is the name of my composite var), I get the error code of composite.map not a function. This error does not come up when I run the exact same code from the previous answer. Can someone explain how to overcome this problem? Here is the page I used:  here is my code and the link to my code:  (point is the long, lat for Lake Manyara, Tanzania)  //load images for composite var sr14= ee.ImageCollection('LANDSAT/LC08/C01/T1_SR') .filterBounds(point) .filterDate('2014-01-01','2014-03-01') .select(['B4','B3','B2']);  // Temporally composite the images with a maximum value function. var composite = sr14.max(); Map.setCenter(35.8244, -3.5799); Map.addLayer(composite, {}, 'max value composite');  var getQABits = function(image, start, end, newName) { // Compute the bits we need to extract. var pattern = 0; for (var i = start; i &lt;= end; i++) {    pattern += Math.pow(2, i); } // Return a single band image of the extracted QA bits, giving the band // a new name. return image.select([0], [newName])               .bitwiseAnd(pattern)               .rightShift(start); };  // A function to mask out cloudy pixels. var cloud_shadows = function(image) { // Select the QA band. var QA = image.select(['BQA']); // Get the internal_cloud_algorithm_flag bit. return getQABits(QA, 7,8, 'Cloud_shadows').eq(1); // Return an image masking out cloudy areas. };  // A function to mask out cloudy pixels. var clouds = function(image) { // Select the QA band. var QA = image.select(['BQA']); // Get the internal_cloud_algorithm_flag bit. return getQABits(QA, 4,4, 'Cloud').eq(0); // Return an image masking out cloudy areas. };  var maskClouds = function(image) { var cs = cloud_shadows(image); var c = clouds(image); image = image.updateMask(cs); return image.updateMask(c); };  var composite_free = composite.map(maskClouds);  Map.addLayer(composite_free, 'composite collection without clouds'); The following time-frequency correspondence illustration is in .    Also a gif animation version (if the animation doesn't show, please open the following image in a new window):    This picture has so much explanatory power, and I would like to replicate it in TikZ for future use.  Here is what I came up with:  \documentclass{minimal} \usepackage{tikz}  \begin{document} \begin{tikzpicture} [x={(1cm,0.5cm)},z={(0cm,0.5cm)},y={(1cm,-0.2cm)}] \draw[-&gt;,thick,blue!90] (0,6.5,0) -- (6.2,6.5,0) node[right] {Frequency}; \draw[-&gt;,thick,red!90] (0,0,0) -- (0,6.5,0) node[below] {Time}; \draw[-&gt;,thick] (0,0,0) -- (0,0,2) node[above] {Magnitude}; \foreach \x in {0.5,1.5,2.5,3.5,4.5,5.5}{   \draw[blue!50] (\x,0,0)   \foreach \y in {0,0.02,...,6.28}{     -- ({\x},{\y},{sin(\x*\y*(157))/sqrt(2*\x)})   };   \draw[blue!90, thick] (\x,6.5,0) -- (\x,6.5,1/\x); }  \end{tikzpicture} \end{document}   This is the output so far.    I have two questions:   How to produce that red superposed sine wave of all the blue sine waves? I don't know if there is a sum function or I have to use loop yet again? How to make the camera projection in TikZ more similar to the perspective in that wikipedia illustration?   Any suggestion and tweaking of the parameters I used in the sample drawing are welcome as well.  Thanks in advance!    Update 1:  Here is a new version using tikz, more readable than the first one. Yet the superposition of the sine waves are done manually...I still don't know how to use foreach to produce a sum.  \begin{tikzpicture}[x={(1cm,0.5cm)},z={(0cm,0.5cm)},y={(1cm,-0.2cm)}] \draw[-&gt;,thick,black!70] (0,6.5,0) -- (6.2,6.5,0) node[right] {Frequency}; \draw[-&gt;,thick,black!70] (0,0,0) -- (0,6.5,0) node[below right] {Time}; \draw[-&gt;,thick] (0,0,0) -- (0,0,2) node[above] {Magnitude}; \foreach \y in {0.5,1.5,...,5.5}{ \draw [cyan!50, domain=0:2*pi,samples=200,smooth]   plot (\y,\x, {sin(4*\y*\x r)/\y }); \draw[blue, ultra thick] (\y,6.5,0) -- (\y,6.5,1/\y); } \draw [red, thick, domain=0:2*pi,samples=200,smooth]  plot (0,\x, {sin(4*0.5*\x r)/0.5 + sin(4*1.5*\x r)/1.5 + sin(4*2.5*\x r)/2.5 + sin(4*3.5*\x r)/3.5 + sin(4*4.5*\x r)/4.5 + sin(4*5.5*\x r)/5.5} ); \end{tikzpicture}   The result is as follows: How do I sort a vector of pairs based on the second element of the pair? If I have a vector of pairs: std::vector&lt;std::pair&lt;int, int&gt; &gt; vec;  Is there and easy way to sort the list in increasing order based on the second element of the pair? I know I can write a little function object that will do the work, but is there a way to use existing parts of the STL and std::less to do the work directly? EDIT:  I understand that I can write a separate function or class to pass to the third argument to sort.  The question is whether or not I can build it out of standard stuff.  I'd really something that looks like: std::sort(vec.begin(), vec.end(), std::something_magic&lt;int, int, std::less&gt;()); How do I reset the Windows XP Administrator password? I have forgotten the Administrator password of my Windows XP installation and locked out. Is there a way to reset it? I do have physical access to the PC. In the Deadpool movie when Wade his mutant cells get activated, his skin changes so he looks like Freddy Krueger (As Weasel referred too). But he obtains healing abilities and his cancer gets cured because of it. He's become an immortal person which can heal any wound super fast.  What I don't understand is, why doesn't his skin heal so he would look like before? I remember that Francis (or Ajax) said that it's a 'side-effect' of mutating, but why wouldn't it heal when he has a healing ability? I want to install selenium webdriver in my Ubuntu 16.04 system for python How to prove that center of $GL_n(\mathbb R)$ is scalar matrices?  Again what can you say about the center of set of all upper triangular matrices and center of set of all diagonal matrices. What are the differences between Factor Analysis and Principal Component Analysis? I have an old Facebook account that I created, uploaded a couple of photos and simply ignored (i.e. no friends added). Now, I can't remember the email address associated with the account and I don't remember the password either. How can I find out which email address I had associated with that account?  P.S. I have created a new Facebook account and my picture can be used to identify me (if I can get someone at Facebook to take a look). Other than that, I'm willing to have that old account deleted altogether if recovery isn't possible.  Is there a way to resolve this issue? My son is 5 years old and sexually active I am a 20 year old female student and I have a 5 year old son who is really sexually active. For instance, he kisses girls by force, he forces them to lick his penis, he "fingers" them, he speaks about sex openly with everyone except me, his father and my family.  There is a whole lot more that he does and the most frustrating part is that when teachers ask him where he saw those things, he says he learned it from me.  We do not even live together.  Currently I am in Cape Town doing my degree and he is in KZN with my mother.  Since he was 8 months old, he went to live with his father because I had to finish high school.  We never lived together. We have tried talking to him and it hasn't helped.  We've punished him but still he keeps on getting worse. What should I do?  I am really angry, embarrassed and confused. If I am not mistaken, this is his third year acting like this. What is the optimal path between $2$ fixed points around an invisible obstructing wall? Every day you walk from point A to point B, which are $3$ miles apart. There is a $50$% chance each walk that there is an invisible wall somewhere strictly between the two points (never at A or B). The wall extends $1$ mile in each direction perpendicular to the line segment (direct path) between A and B, and its position can be at any random location between the two points. That is, it can be any distance between A and B such as $0.1$ miles away from A, $1.5$ miles away, $2.9$ miles away.... You don't know if the wall is present or where it is until you walk into it.  You must walk around the wall if present as there is no other way to circumvent it.  Assume the wall is negligible thickness (like a force field), all ground is perfectly flat, and the y coordinates at both A and B are $0$ (although I don't think the optimal path will change much if they weren't).  What strategy minimizes the average expected walk distance between A and B?  How do we know for certain this strategy yields the shortest average walking distance?  To get the $100$ bounty points, I would like a convincing argument from you as to why you feel your solution is optimal and cannot be beaten.  For those of you using computer simulation, anything reasonably close to optimal is a candidate for the bounty.   Can anyone beat the optimal solutions submitted so far?  There are still a few days to try.  Even a slight beat (if not due to roundoff error or some other error) would help prove previous solutions are non-optimal.  You can just use the table of $31$ points (x-y coordinates) and compute that path length and then if you can find better then I will accept that answer.  I think by Sunday night I may have to award the bounty otherwise it may get auto-awarded. Books or resources for learning unified view of classical statistics? I did a science PhD doing applied bayesian statistics, and I liked it so much that I decided to shift to statistics.  For the last 2-3 years have been working at a firm that has more of a frequentist focus.  It seems to me that the bayesian approach (at least what I learned) has an underlying theory that was laid out and I could understand.  Now I find this - more classical - field fascinating but I am looking for some resources to get a unified view of the matter.  For example, I am learning and applying anovas, F-tests and chi-squares, thinking about degrees of freedom, etc but part of me is looking for deeper understanding that would make it more than just methods.  Does anyone have any suggestions on books or more resources that provide such a unified, deeper focus? Lets say I have a domain already, for example www.automobile4u.com (not mine), with a website fully running and all.  The title of my "Website" says:    &lt;title&gt;Used cars - buy and sell your used cars here&lt;/title&gt;   Also, lets say I have fully SEO the website so when people searching for the term buy used cars, I end up on the second or first page.  Now, I want to end up higher, so I go to the google adwords page where you can check how many searches are made on specific terms.  Lets say the term "used cars" has 20 million searches each month.  Here comes the question, could I just go and buy that domain with the search terms adress, in this case www.usedcars.com and make a redirect to my original page, and this way when people search for "used cars", my newly bought domain name comes up redirecting people to my original website (www.automobile4u.com)?  The reason I believe this benefits me is because it seems search engines first of all check website adresses matching the search, so the query "used cars" would automatically bring www.usedcars.com to the first result right?  What are the downsides for this?  I already know about google spiders not liking redirects, but there are many methods of redirecting...  Is this a good idea generally? I'm about to travel to the US, where iPods / AirPods / iPhone are much cheaper than in my country.   I wonder if Apple's warranty is international, and/or what warranty coverage exists when I return to my country.  Where can I understand what Apple Warranty covers in the US when products leave the US? 80's Animated movie: An old man joins mission to save a boy stranded on a hostile world A guy on a space ship picks up a distress call, a boy is stranded on a planet with a hostile environment. He &amp; his crew go to the rescue, stopping on the way to pick up an old man who comes with them. Most of the top of the old guy's skull is metal, from an old injury.  They've various adventures on the way (their ship is boarded by pirates/bandits/hostile forces at one point).  They get to the planet with the boy. They've limited time to save him as the planet is being moved back in time. (I can't remember why) When they find the boy, he's being attacked by giant wasp-type-things.   The boy is injured on the top of his head. The old guy dies protecting him. The boy gets shifted back in time with the planet and - you guessed it - survives, grows up and turns out to be the old guy.  Now that I've remembered some of it, the bits I can't remember are driving me crazy. I'd love to see this again, if I could identify it I might be able to track down a copy.  I'd swear I saw this mid 80's on morning TV, but it I could be out by 5 years either way. Thanks "the better" vs "the best" of two players