Extracting sub-matrices from a matrix
How to divide an image into blocks in MATLAB?
"INSERT IGNORE" vs "INSERT ... ON DUPLICATE KEY UPDATE" While executing an INSERT statement with many rows, I want to skip duplicate entries that would otherwise cause failure. After some research, my options appear to be the use of either:  ON DUPLICATE KEY UPDATE which implies an unnecessary update at some cost, or INSERT IGNORE implies an invitation for other kinds of failure to slip in unannounced.  Am I right in these assumptions? What's the best way to simply skip the rows that might cause duplicates and just continue on to the other rows? Story on quantum indeterminacy: protagonist has to “quantum select” a portable computer’s state How to use pagenumbering in the document? In my Master thesis, I would like to have the title page without any page number and an acknowledgments section and the table of contents with roman numbers. The rest of the document should be numbered arabic.  I have tried this, to have roman numbers for the Table of contents and normal numbers for the rest.  \documentclass[12pt,ngerman,openany]{report} \usepackage{titlesec} \usepackage{titletoc} \usepackage{cite} \usepackage[a4paper]{geometry} %\usepackage[T1]{fontenc} \usepackage[utf8]{inputenc} \usepackage[ngerman]{babel} %\usepackage{ngerman}{babel} \usepackage[T1]{fontenc} \usepackage{graphicx} \usepackage{float} \selectlanguage{ngerman} \usepackage{amssymb} \usepackage{amsmath} \usepackage{url} \usepackage{epstopdf} \usepackage{scrhack} \usepackage{listings} \usepackage{caption} \titleformat{\chapter}{\rmfamily\huge}{\textbf\thechapter.}{25pt}{\huge\textbf} \defcaptionname{ngerman}{\lstlistingname}{Code} \defcaptionname{ngerman}{\lstlistlistingname }{Codeverzeichnis}  \lstloadlanguages{R}  \lstset{% general command to set parameter(s)    basicstyle=\sffamily\footnotesize, % print whole listing small    keywordstyle=\sffamily\footnotesize\bfseries, % ubold black keywords    identifierstyle=, % nothing happens    commentstyle=\sffamily\footnotesize\slshape, % green comments    stringstyle=\sffamily\footnotesize, % typewriter type for strings    showstringspaces=false, % no special string spaces    numbers=left,    numberstyle=\sffamily\footnotesize,    stepnumber=1,    numbersep=10pt,    showspaces=false,    showtabs=false,    frame=lines,    morecomment=[l]{\%},    float=htbp,    numberbychapter=true  }   \begin{document} \let\cleardoublepage\clearpage   \pagenumbering{roman}  \tableofcontents  \clearpage  \vspace*{75mm} \chapter{Einleitung} \section{Motivation} bla bla bla \section{Ziel}  bla bla \chapter{Stand der Technik zur Mustererkennung} \section{Die Zeitreihen} bla bla \subsection{Beschreibung} bla bla \subsection{Erklärung}  bla bla  \subsection{Vorhersage} bla bla \subsection{Kontrolle} bla bla \section{Feature Extraktion} bla bla \subsection{Autokorrelation} \subsection{Was ist Autokorrelation?} bla bla   \subsection{Autokorrelation und Zeitreihen} bla bla  \subsubsection{Zeitreihe-Diagramm}  bla bla \subsubsection{Lagged Streudiagramm} bla bla  \subsubsection{Autocorrelation-Function (Korrelogramm)} bla bla \subsection{Spektralanalyse} \subsection{Was ist Spektral-Analyse} bla bla \end{document} Testing convergence of series $\sum_{n=3}^\infty\frac{1}{n (\ln(n))^p(\ln\ln(n))^q}$ Proof of a formula involving Euler's totient function: $\varphi (mn) = \varphi (m) \varphi (n) \cdot \frac{d}{\varphi (d)}$ The third formula on the  states that $$\varphi (mn) = \varphi (m) \varphi (n) \cdot \dfrac{d}{\varphi (d)} $$ where $d = \gcd(m,n)$.  How is this claim justified?  Would we have to use the Chinese Remainder Theorem, as they suggest for proving that $\varphi$ is multiplicative? Compton scattering vs. photoelectric effect Say a photon hits some atom.  What determines whether there will be a photoelectric effect (photon is absorbed, electron is released) or whether there will be a Compton scattering (the photon is  scattered at some angle, and the electron is released with another direction)? What are the use cases of SO_REUSEADDR? I have used SO_REUSEADDR to have my server which got terminated to restart with out complaining that the socket is already is in use. I was wondering if there are other uses of SO_REUSEADDR? Have anyone used the socket option for other than the said purpose? I was wondering how far in imaging physics had gotten. Do we hold the technology to actually take a picture of, say, an alpha particle, or even a single atom?  I realise we aren't talking about camera pictures, so what kind of imaging techniques have taken images/is most likely to be the technique to take an image of a single atom? Can't flag or close questions on all sites Whenever I try to flag or close a question here, when clicking the submit button the button gets disabled, three dots animating and nothing really happens.  JS console show a single error:  Flagging:     Uncaught TypeError: Cannot read property 'flagSubmitting' of undefined    Closing:     Uncaught TypeError: Cannot read property 'closeSubmitting' of undefined   Please fix, programming questions and spam are beginning to pile up. :(  Update: appears to work fine from within the review system, but otherwise it's the same on Stack Overflow as well How to use grep output as a path for cd? Reference for creative set criterion theorem So the stories of the Hunger Games are set in , a post-apocalyptic society situated in North America. Is there anything to explain what caused the Apocalypse? Whether from the main books, any extra material or interviews? (No fanfic please.)  As well as the cause, is there any indication of when the apocalypse happened? And how long after the apocalypse are the events of the Hunger Games? Often, TeX outputs underfull hbox and vbox warnings when running and in the generated log file. What are these and how can I get rid of them? Cancellation of Direct Products A general explanation of rim, tire and tube specifications How should we handle downvote retaliation? Is it possible that your friends can join your Hamachi server when they don't have Hamachi? Does anyone know how to do that??!! Variable number of arguments in C++? Under what circumstances can the word "be" be used directly without any change? Possible Duplicate:          2 examples first:  1.It is announced that the accounting class of the 3rd and 4th hours on the morning of this Wednesday be cancelled  2.It is expected that everybody and each household be on guard  Someone told me this kind of examples above appears in the textbook as strict sentences to be taught in the classroom, so is that right for the usage of be  Meantime I looked up the word be at thefreedictionary.com and found one piece of interpretation says :      Archaic Used with the past participle of certain intransitive verbs to   form the perfect tense: "Where be those roses gone which sweetened so   our eyes?" (Philip Sidney).   So is there any connection between the archaic usage &amp; the examples above? BTW, how to understand the short phrase "the 3rd and 4th hours". Many thanks! How do I prevent the blank screensaver when using keyboard shortcut to lock the computer?