First, if this is the wrong place then I have to say that someone needs to fix the links in the footer of Careers site (this is how I ended here).  Anyway, I was looking for "C" jobs, and found lots of unrelated jobs instead, and lots I mean LOTS. Thus the site is impossible to use.  I want a C job, not C++, Obj-C, or even things that are not even related at all (I got returns for perl, python, mysql, and lots of other random stuff).  So, Careers site should have a way to search only what you want, maybe use SO search system, where if you type [c] it will search ONLY, and ONLY REALLY ONLY the tag C (instead of random words in the description that contains the character C).
I am attempting to search jobs by tag on StackOverflow Careers. On SO, this is done using square brackets, but that is simply doing a keyword search, and I still get results that don't have the tag I am looking for.  For example, when I search for the keyword "android", I get this:        which is the same as when I search for the keyword "[android]":        Is there a format I can use to search jobs by tag? If not, I believe this would be a nice feature (seems intuitive for the Stack Exchange invite-only job site).
How to make a figure span on two columns in a scientific paper? If I just try to set the figure's size to 0.9\textwidth my figure will just end up on the right column, sized to be two-columns wide.  Has anyone done this before? Differences Between Row Echelon and Reduced Row Echelon Let $$A =\begin{bmatrix} 1&amp;3&amp;-6&amp;2\\5&amp;12&amp;-24&amp;7\\9&amp;15&amp;-30&amp;6\end{bmatrix}$$  $$RREF(A) =\begin{bmatrix} 1&amp;0&amp;0&amp;-1\\0&amp;1&amp;-2&amp;-1\\0&amp;0&amp;0&amp;0\end{bmatrix}$$ $$REF(A) =\begin{bmatrix} 1&amp;3&amp;-6&amp;2\\0&amp;1&amp;-2&amp;1\\0&amp;0&amp;0&amp;0\\\end{bmatrix}$$  Now, provided this information, it can be found that the basis for the nullspace of $A$ using the $RREF(A)$ is: $$\begin{pmatrix} \begin{bmatrix} 0\\2\\1\\0 \end{bmatrix}, \begin{bmatrix} 1\\-1\\0\\1 \end{bmatrix}\end{pmatrix}$$  Using the $REF(A)$ the "basis" for the nullspace is:  $$\begin{pmatrix} \begin{bmatrix} 6\\2\\1\\0 \end{bmatrix}, \begin{bmatrix} -2\\-1\\0\\1 \end{bmatrix}\end{pmatrix}$$  Is the "basis" that I provided for the $REF(A)$ actually a basis? How does the  $REF$ and $RREF$ of a matrix differ? If a maximal subgroup is normal, it has prime index I'm having trouble with an exercise in "Introduce to the theory of group" book. This is problem:  Let $M$ be a maximal subgroup of $G$. Prove that if $M$ is a normal subgroup of $G$, then $[G: M]$ is finite and equal to a prime. What is the purpose of the 'nobody' user? After I read  I noticed that there is a user account named 'nobody' in my Ubuntu system.   Also I noticed that I can login in this account from terminal using the following command and my password:  sudo su nobody     It doesn't mind me at all, but I want to know what is the purpose of this user? Is it created by default on a fresh install of Ubuntu or is created by installing a particular package? I might want to answer my own question because:  I arrived at a solution before there were any other correct answers or I like mine better, can I still answer my own question?  I have a folder with lists of code snippets for things I always forget or get wrong, such as regular expressions for processing XML, common WinForms control idioms, etc. Is it considered poor etiquette for Stack Overflow to ask a question I already know the answer to, and then self answer, just so it gets recorded on the website?   Related:          For more information, see &quot;&quot; in the . A Tweedie distribution can model skewed data with a point mass at zero when the parameter $p$ (exponent in the mean-variance relationship) is between 1 and 2.   Similarly a zero-inflated (whether otherwise continuous or discrete) model may have a large number of zeros.  I'm having trouble understanding why it is that when I do prediction or calculate fitted values with these kinds of models, all of the predicted values are non-zero.  Can these models actually predict exact zeros?  For example  library(tweedie) library(statmod) # generate data y &lt;- rtweedie( 100, xi=1.3, mu=1, phi=1)  # xi=p x &lt;- y+rnorm( length(y), 0, 0.2) # estimate p out &lt;- tweedie.profile( y~1, p.vec=seq(1.1, 1.9, length=9)) # fit glm fit &lt;- glm( y ~ x, family=tweedie(var.power=out$p.max, link.power=0)) # predict pred &lt;- predict.glm(fit, newdata=data.frame(x=x), type="response")   pred now does not contain any zeros.  I thought the usefulness of models such as the Tweedie distribution comes from its ability to predict exact zeros and the continuous part.  I know that in my example the variable x is not very predictive. Spacing before and after section titles Are all continuous one one functions differentiable? I know some countries such as UK has the steering wheels of their cars on the right side. But as we can see, most of the Europian countries uses it at the opposite side. Since I used to drive a car with left-steering wheel I found it impossible to drive a car with right-steer!  Not curiosity, but I am trying to map if this issue is related to User Experience or not. Installed MySQL but still says command not found I downloaded MySQL's rpm bundle from the site, converted it to a .deb file using alien and installed it by saying sudo dpkg -i mysql-server_5.6.14-2_amd64.deb. However, when I say mysql in the command line, it gives an error that it is not installed. What do I do?  I am on Ubuntu GNOME 13.10 64-bit I wonder how a researcher send an unsolicited email to another one asking for feedback to their work. I guess it will be something like this?  Hello Dr. X To introduce myself, I am Y, in institute Z. I'm sorry if this email is not convenient at this time, but my work about A is highly relevant to your work in B, so I think it will be interesting to you too. If possible, can you take a look at it and tell me what you think? Here is the link:  Thank you for your reading, hope you enjoy it.  I wonder if the summary/abstract should be included in the email too, since the principle for  is to show everything you know about it. Maybe it's not necessary, since the title of the link should prove its interestingness nevertheless? I'd like to have your confirm. I'm also interested in the case where Y has no Z, and the link is just a collection of observations posted in a blog, not a full paper with proper citation and literary review. It is possible that the observations may have been covered in the field, but Y isn't aware of that yet. I also think that if the link is interesting enough, then putting a tracking method in there is fine too? Even if they finds out, they wouldn't feel insulted either, because they find that the link is indeed interesting.  Related: •  •  • Each event has two possible outcomes: a and b.  Each event is independent.  Outcome a has $X\%$ chance of happening.  If we run $Y$ number of such events, what are the chances of getting $K$ outcomes a in a row, at least once?  To put it in practical terms imagine a series of coin tosses. Each coin toss has two possible outcomes: a = heads and b = tails. Outcome a = heads has a chance of $50\%$. If we run $Y = 100$ number of coin tosses, what are the chances of getting $K = 10$ outcomes a=heads in a row, at least once?   I'm using the practical example only so I can express the idea more clearly. I'm interested in finding out the general formulas and computations so that I can run the calculations for any $X$, $Y$, or $K$.  I would also be very interested in knowing how the probabilities would change if the events would not be independent. What if the more outcomes a we have in a row the bigger the chance of getting an outcome a in the next event? What if it's the other way around, and the more outcomes a in a row we have the lower the chance of getting another a? We have a pool of N number of balls.  There are: A number of white balls (W), B number of green balls (G), C number of blue balls (B), and D number of pink balls (P)  In how many ways (combinations) we can pick X number of balls from this pool? Is there a formula for something like this?  This is similar to combinations with replacement, but there are limitations to how many times a certain object can be replaced. What command should I use to rotate wood to S,N,W,E,D and U?  I read the entire world edit guide and tried some things but all the results are not satisfactory. In a problem, we have to differentiate : $$ y = \arcsin (2 x \sqrt{1 - x^2}),$$ given: $$-{1/(\sqrt2)} &lt; x &lt;{1/(\sqrt2)}$$.   My approach :  Put $x = \cos (p)$, so y reduces to:- $y = 2p = 2 \arccos (x)  \implies$ ${dy}/{dx}$ $ = -{2}/{\sqrt{1-x^2}}$   But the solution given is without the minus sign, so I am doing something wrong here but don't know what.  So please tell me what I am doing wrong and how to correct it. I recently installed an SSD and AFAIK Ubuntu makes a weekly FSTrim on SSD's that support it.  Is there a log file of this trims? Was the singularity at Big Bang perfectly uniform and if so, why did the universe lose its uniformity? What's amazing about these open world games is the freedom I have as a player. If I don't want to follow the main story line for a while, and just explore, I can do that, and the game won't break.  On the other hand I don't particularly like the feeling of having made a significant, bad choice in the game, among the lines of Yeah, that dialog option you selected hours ago? This amazing quest line is now off limits.  If I recall correctly, in Morrowind, I had to progress through a few different guilds' quests in the right order, otherwise it'd have stopped my progress in a few guilds.  As a Skyrim example, it doesn't appear that the very first choice made in Helgen at the very beginning has much significance. If someone told me It's not that significant, you still get to choose sides (or, rather not told me "This is important"), that'd help.  Another example: Based on a question I read here, I should probably make sure that I don't throw away any of the dragon priest masks and need to make sure to collect one during a specific quest. This would be relevant for this topic if I could easily miss it otherwise while doing that question.  This includes accidental problems possibly caused by bugs: It appears .  It doesn't matter too much which of the love triangle guys in Riverwood I support: That's not nearly significant enough.    Are there non-obvious, hidden decision points in the quests and story lines? When playing in a certain area, doing a certain quest, what do I need to make sure to do or not do, to not accidentally prevent me from getting or achieving something significant?  I still want to explore on my own, but want to be aware of which choices are important.  This is somewhat related to . Once in a while you wish to address a comment to someone in particular, so you type @ and then you pause ... because the username is  or .  Short of using copy-paste to get their username right (which is even more cumbersome on a mobile device), is there another way around this? In a few cases I've noticed that the system will attempt to "promote" a comment to a reply, but I'm not sure if that's very reliable.  Should user names at least start with a normal letter?  Update  The auto-complete feature seems to normalize Zalgo'ish usernames, so typing the letter L will trigger the suggestions as expected; this is of course knowing that the name actually spells "lawrence", which may not always be obvious.  Knowing the way of the symbol ninja would surely help to type Ω using only the elbows as well, but not everyone is blessed with the same keyboard layout.  Suggestion  It would be nice to have a reply feature like this:        When ↳ reply is clicked, it will automatically populate the comment box with @username pre-filled in.   Additional notes  To clarify, I'm not suggesting to put the "reply" on all comments, as proposed , because in most cases the owner of a post is already notified of a new comment; this would strictly be to effect cross-commenter communication. How is prototyping done in a professional EE environment? Do you do your prototypes on breadboards, on copper clad boards, Manhattan style, or do you just draw schematics, order PCBs made and assembled and work with them, hacking here and there if necessary?