Booking 2 ways ticket, not onboard 1 way, consider canceling both?
Why are one-way plane tickets more expensive than return tickets?
Complex number question on proving an inequality. If $|z_1|=1,|z_2|=1$, how can one prove $|1+z_1|+|1+z_2|+|1+z_1z_2|\ge2$ Tools for tracking NPC/PC relationships and attitudes I have always had difficulty keeping track of NPCs, their attitudes and their relationships with each other and the PCs. I find relationship webs/diagrams are helpful, but find them difficult to keep up to date and accurate from session to session.  Are there any tools that would help with this task? I am aware that some general mapping software exists, but am more interested in tools specifically designed for RPGs. Also, I would prefer a graphical interface if software is suggested, and to not have to learn a text based language to define the diagram. However, if it turns out that the only tools available are more generalised, and/or complex, I would still like to hear about them as answers. How do you rename root? Not that it's a very good idea to change it, but for fun. According to  post, there are still some problems even after changing entries in /etc/passwd, /etc/shadow, and /etc/sudoers. Any suggestions? Why are naturals < modulus equal if congruent? [uniqueness of remainder] Let $a$, $b$, and $n$ be integers with $0 \le a \lt n$ and $0 \le b \lt n$. Suppose $a \equiv b \pmod n$. Then $a-b=0$ and $a=b$. Why does the congruence of two non negative integers imply that they must be equal? Using restroom on airplane while fasten seatbelt light is on? This question about  over on  made me wonder what a passenger is supposed to do when they urgently have to use the restroom while the fasten seat belt light is on. FAA regulations require passengers to obey the seat-belt sign, even if flight attendants do not.  I saw this happen on a flight where an older gentleman asked the flight attendant if he could use the restroom, and she said "not until the light is off". The flight had been free of turbulence for 15 minutes or so by this time, and the flight attendants were walking freely throughout the cabin, collecting post-meal trash, etc. The gentleman who asked to use the restroom appeared to be in quite some discomfort, and practically ran to the restroom when the light went off 10 minutes later.  So what is a passenger supposed to do when he isn't permitted to use the lavatory, when he has to go and can't wait? Just go in their seat? How to implement Enums in Ruby? Contraction of quotient ideal is quotient of contractions? How can I highlight text before a character with listing? All is in the title. I would like to add a color to the text before a character with listing package.  For example, I would like to add a color to text between the beginning of a line and : or =, in a makefile.  I tried to use moredelimiters but I did not succeed.    \documentclass{article}  \usepackage{listings} \usepackage{xcolor} \definecolor{keycolor}{RGB}{172, 42, 42} \definecolor{mbleu}{RGB}{64,96,127} \definecolor{vimvert}{RGB}{46, 139, 87}  \lstdefinestyle{global}{   basicstyle=\ttfamily\scriptsize\color{black!90},%   stringstyle=\itshape\color{magenta},%   showstringspaces=false,%   keywordstyle={\bfseries\color{keycolor}},%   commentstyle=\color{blue}\slshape,%   framexleftmargin=1mm,%   backgroundcolor=\color{black!2},% }  \lstdefinestyle{makefile}{   style=global,%   morecomment=[l][commentstyle]{\#},%   emphstyle={\color{vimvert}},%   moredelim=[s][emphstyle]{\$(}{)}% }  \begin{document}  \begin{lstlisting}[style=makefile] .SUFFIXES: .inc .f .f90 .F  # all CPP processed fortran files have the extension .f90 SUFFIX=.f90  #----------------------------------------------------------------------- # this release should be fpp clean # we now recommend fpp as preprocessor # if this fails go back to cpp CPP_=fpp -f_com=no -free -w0 $*.F $*$(SUFFIX)  vasp: $(SOURCE) $(FFT3D) $(INC) main.o      rm -f vasp     $(FCL) -o vasp main.o  $(SOURCE)   $(FFT3D) $(LIB) $(LINK) makeparam: $(SOURCE) $(FFT3D) makeparam.o main.F $(INC)     $(FCL) -o makeparam  $(LINK) makeparam.o $(SOURCE) $(FFT3D) $(LIB) zgemmtest: zgemmtest.o base.o random.o $(INC)     $(FCL) -o zgemmtest $(LINK) zgemmtest.o random.o base.o $(LIB) dgemmtest: dgemmtest.o base.o random.o $(INC)     $(FCL) -o dgemmtest $(LINK) dgemmtest.o random.o base.o $(LIB)  ffttest: base.o smart_allocate.o mpi.o mgrid.o random.o ffttest.o $(FFT3D) $(INC)     $(FCL) -o ffttest $(LINK) ffttest.o mpi.o mgrid.o random.o smart_allocate.o base.o $(FFT3D) $(LIB) kpoints: $(SOURCE) $(FFT3D) makekpoints.o main.F $(INC)     $(FCL) -o kpoints $(LINK) makekpoints.o $(SOURCE) $(FFT3D) $(LIB)  clean:       -rm -f *.g *.f *.o *.L *.mod ; touch *.F \end{lstlisting}  \end{document} Execute function when post is published I try to use this function i have created when a post is published for the first time.  function a_new_post($post){   $post_id = $post-&gt;ID;    if ( !get_post_meta( $post_id, 'firstpublish', $single = true ) ) {       // ...run code once       update_post_meta( $post_id, 'firstpublish', true );   } } add_action( 'draft_to_published', 'a_new_post' );   I can't see anything wrong with it, but when i try to create some sample posts i check the database and the field "firstpublished" has not been created.  Does anyone see anything wrong? Output to stdout and at the same time grep into a file Auto Package download for TeXLive I use MiKTeX on Windows and quite satisfied with it. Recently I started switching all my tasks toward open-source alternatives, and in the course I would love to use Linux. In Linux TeXLive is available as alternative to MiKTeX. The thing I really like about MiKTeX, is its ability to install packages automatically. Can I do the same in TeXLive too? Is there a way I can enable such or install some plugins for it?  I am using Fedora 18, if that's needed. I wanted to send a single email to different users. I save an email to drafts and send the email to a user and it goes to the sent box instead of staying in the drafts box. Is there a way I can send an email repeatedly from the drafts box? Is there some rule against ending a sentence with the contraction "it's"? I heard this lyric in a song the other day and it just sounded so wrong that I assumed it must be incorrect grammar, but I can't find any specific prohibition that applies.     That's what it's.    That rolls off your tongue with the grace of a moose in a tutu, but I can't figure out why.  There is clearly no problem with ending other sentences with a contraction. These sound fine.     I thought I could, but I can't.   Stop touching that, it will fall off if you don't.   You say that the sky is green, but it isn't.   Also, it sounds just fine if you remove the contraction:     That's what it is.   So what's up with this construction? Should it be avoided? Security of GCM if Implemented with Stream Cipher instead of Block Cipher How to find application's path from command line? For example, I have git installed on my system. But I don't remember where I installed it, so which command is fit to find this out? Change default shell for Terminator I want to change the default shell of Terminator to zsh. In /etc/passwd/ I've changed the default shell to /bin/zsh. This settings changes the default shell in LXTerminal (the default terminal on Lubuntu), but not in Terminator. So I tried chsh -s /bin/zsh, but that doesn't work either. The Terminator  says:  How do I change my default shell? Terminator will always start the shell specified by the SHELL environment variable. (It will fall back to /bin/sh if the SHELL environment variable isn't set.) You could simply influence Terminator's environment, but the best solution is to tell your operating system which shell you'd like, and it will ensure that SHELL is set correctly for all applications, not just Terminator. See the documentation for your operating system for details on how to change your default shell.  So I expected my attempts to work, but they don't. How can I change the default shell in Terminator. Should a toggle button show its current state or the state to which it will change? Why is there an electric field in a wire even though it is a conductor? If you take a perfect conductor, there cannot be a field across it since if there were, the particles would arrange themselves in a way to cancel out the field right?  Yet, why does the same not hold true for a wire. A wire is essentially a long, thin conductor yet electrons do indeed flow so there must be an electric field.  Does this not contradict with what happens in a conductor? Why don't the electrons re-arrange to cancel out the electric field? Please add a reply button to messages in the pinned/starred section I've run into this a few times; I'll rejoin chat after being away for a while and notice something interesting in the starred section.  I'd like to reply directly to the message but there's no reply button.  Currently, the only ways to explicitly reply to one of those messages are either:-   find the message by scrolling up and looking for it, then click the reply button or; copy and paste the permalink, deleting all the way up to the fragment identifier and adding the colon at the start.   Please add a reply link, even if it just goes in the popup menu it's an improvement. Is $\exists x(x=a)$ a valid formula in first order logic with equality? Under , is $\exists x(x=a)$ true in every interpretation in first order logic (FOL) with equality? If so, could $\exists x(x=a)$ be considered a tautology? This question was motivated by  which was closed for lacking clarity. Here I have attempted to add that clarity myself so that the same question can be useful to others who are wondering a similar thing. This is a self answer question.