Function split in C++?
How do I iterate over the words of a string?
Write this equation I want to write this equation in this way down but I have been unsuccessful. How can I improve this codes in order to get the equation below?  \[ DeltaC{t} = \left\{ \begin{array}{ll}  -1.40- 0.588w_{t-1} - 0.5351\DeltaC_{t-1}+ 0.169\DeltaBC_{t-1} &amp; \mbox{ if $w_{t-1}&lt;- 0.62$} \\ -1.40 - 0.588w_{t-1} - 0.5351\DeltaC_{t-1} + 0.169\DeltaBC_{t-1} &amp; \mbox{$w_{t-1}&gt;0.62$} \end{array} \right. \] How do I extract an ISO on Linux without root access Selecting the right crank length What is the best way to determine the correct crank length for my height and more specifically my leg length? Connected compact covering space of torus is homeomorphic to $S^1\times S^1$ Ubuntu 14.04, problem when install gstreamer1.0-libav, unmet dependencies Why are useful questions on StackOverflow being closed as non-constructive? Useful threads are being closed as "not constructive:"     This question is not a good fit to our Q&amp;A format. We expect answers to generally involve facts, references, or specific expertise; this question will likely solicit opinion, debate, arguments, polling, or extended discussion. See the .   For example,  was very useful for me since I am new to obfuscation and the question gave me a start. Also that question has lots of votes and bookmarks - these alone are the  markers of usefulness. The question is closed anyway. No idea why.  Same happened to my question, , which received one bookmark immediately.  I was waiting for an answer with the two products downloaded and installed.  I desired that experienced people would share their thoughts and point me to the better one. No. Closed. I.e. I must go to some other forum and ask there or I must search on Google and write down the pros and cons of each myself. I am not asking questions just because I have tons of time and want to chat; I need an answer, that's why I am asking. I am asking because I think that SO has the most professional people to answer and because I didn't find a good answer in Google.  I saw other questions closed which I myself found to be useful and I bookmarked some of the closed questions.  UPDATE  If I want people who have an experience which I do not have with some software products and I want to see which product is better in the terms of usability and reliability, not just better in terms of the price or has a better official website or better described on the official website, how do I ask this question? Or is this a question which I cannot ask on SO? I.e. this sort of information is not available on SO?  Is this one breaking the rules as well:  ? I've googled and also searched the answers here but couldn't find my problem so here goes:  I know how to bevel a curve using another object and when I try it with a normal circle it's fine. But I'm trying to use this flat oval shape to bevel a larger curve of the same shape and it's not following the curve at the correct rotation. I've tried everything, rotating the bevel object, clicking random options in the object data menu.. I can't seem to budge it from looking how it is in the screenshot. In the screenshot you can see the curve I've failed to bevel correctly and also the bevel object in the bottom right.  Basically, I want the flat part of the oval to be above and below the curve, not on the sides as it is. I hope that makes sense. Anyone know what I need to do? Rational solutions of $y^2 = x^3 - x$ I tried to install Xubuntu 13.10 on an older computer. I noticed some difficulties during installation that may be relevant to my problems. Notably:   The screen resolution was extremely low. The windows were much larger than the screen and I had to move them around to get to the "Next" button. The mouse cursor was a blur of colours that was flashing all the time.   The installation finished and I tried to reboot the computer. Immediately I got:  error: attempt to read or write outside of disk 'hd0'.  Entering rescue mode...  grub rescue&gt;   I made a  USB disk, booted it and chose the default repair. The application told me that the problem is repaired and that If this does not solve my problem I should show  to someone who can help me.  What should I do next? I already tried to install Ubuntu and Xubuntu, both with no success.  EDIT:  I found a workaround.   Insert the Xubuntu live USB Select "try Xubuntu" In the settings menu select "install Xubuntu"   This fixed the problem for me. Since it is solved I cannot test the answer. Laplace transform of $1/t$ Let's disallow moderator nominations from people who've been suspended in the past year How to make crontab email me with output? How can I make crontab email me with the output of its jobs? I have MAILTO=redacted@yahoo.com.au above the jobs, but it doesn't work.  I know I need to use something like Postfix or Sendmail but for the life of me I cannot find out how to achieve this. I've searched and searched for a simple guide on setting up Postfix but they're all insanely complicated and expect you to be setting up a whole server to send and receive email and to know all the terms (like, what is a domain name for outgoing emails?).  All I want to do is have crontab email me. Why is this so difficult??  Additional Info:  My crontab file looks like this:  MAILTO=redacted@yahoo.com.au 1 0 * * * ~/Desktop/toskymesh.sh 59 6 * * * ~/Desktop/tooptus.sh 0 3 * * * snapraid sync   More Additional Info:  The output of ps -ef | grep '[s]endmail'  root 6840 1370 0 10:26 ? 00:00:00 sendmail: MTA: accepting connections   I know for sure cron is working, but I'm testing the mail command with echo Test | mail -s Test redacted@yahoo.com.au anyway. Virtual functions and performance - C++ In my class design, I use abstract classes and virtual functions extensively. I had a  feeling that virtual functions affects the performance. Is this true? But I think this performance difference is not noticeable and looks like I am doing premature optimization. Right? I have a few satellites and stations orbiting my planets, but I'd like to add onto them. I've seen numerous videos on using docking clamps to attach my new ship to the existing station, but can I do that on a part-by-part basis? For example, I take an extra fuel tank up there, can I attach just the tank to my station, then send my vessel back to Kerbin? I'm not talking about refueling, but rather transferring individual parts from my ship to the station in orbit.  I'd prefer to not have to use an unmanned probe and jettison everything but the desired part in space after docking if possible, but if that's the only way I guess I don't have a choice. No association bonus for Area51? My Area51 account crossed 200 rep today, but still other accounts don't reflect the change in reputation. When will the changes be applied? or is there no association bonus for Area51 account? Schengen visa in US without H1B stamp I'm very new to latex, and I've noticed that using a book class causes the text on one page to be on the right and then left on the next and so on. I'd like for it to all to be on the left or centered. How can I change this? Potential energy of an infinitesimal length of elastic rod Prove $n\mid \phi(2^n-1)$ If $2^p-1$ is a prime, (thus $p$ is a prime, too) then $p\mid 2^p-2=\phi(2^p-1).$  But I find $n\mid \phi(2^n-1)$ is always hold, no matter what $n$ is. Such as $4\mid \phi(2^4-1)=8.$  If we denote $a_n=\dfrac{\phi(2^n-1)}{n}$, then $a_n$ is , but how to prove it is always integer?  Thanks in advance! Why is variance squared?