Allow only one website using iptables in a linux router
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Computation of a limit involving factorial $\lim_{n \to \infty} \sqrt[n+1] {(n+1)!} - \sqrt[n] {(n)!} = \frac{1}{e}$ How to make a button appear as if it is pressed? What is the best way to include R code in the Latex paragraph I am a newbie in Latex. I have two simple questions regarding including R code in Latex.  Q1: For a block of R code, I use 'listings' package, as follows.  \documentclass[12pt]{report} \usepackage{listings} \begin{document} \begin{lstlisting}[language=R] &gt; dpareto(4, 2, 3) [1] 0.09375 &gt; dpareto(4, -2, 3) [1] NaN &gt; dpareto(seq(-1, 4, 1), 2, 3) [1] 0.0000000 0.0000000 0.0000000 0.0000000 0.2962963 0.0937500 \end{lstlisting} \end{document}   I feel it's not professional. What is the best way to present the block of R code?  Q2: For code pieces in the paragraph, for example I wish to include a R function, or variable, or package name in my Latex context, what is the best way to do that? Error to calculate date diff with DateTime class Powerset of set with empty sets I am working on a problem with the following set:  $$S =  \{\varnothing,\{\varnothing\}\}$$  My solution was: $P(S) = \{\varnothing, \{\varnothing\},\{ \varnothing , \{ \varnothing \}\}\}$, but the solution on the textbook shows: $P(S) = \{ \varnothing , \{ \varnothing \}, \{\{\varnothing\}\}, \{ \varnothing , \{ \varnothing \}\}$  Where does the $\{\{\varnothing\}\}$ come from?  Thanks What do Android application permissions mean? When installing an application, the application lists permissions that it needs to perform its  functions.    I am creating this list of the the system defined permissions and a description of what they mean. It is a community wiki so if new permissions are added in the future they can be added to this list. completing the square for Gaussian multivariate estimation I have been trying to derive the posterior distribution in the case of weighted Bayesian regression in the case of multivariate normal distribution for a few days and have been stuck. I am not sure if this is due to lack of my linear algebra skills or if I have done something really wrong.  In my case, the distributional assumptions are:  $$ y = N (B x, W^{-1} \nabla) $$  The parameters $B$ have a normal prior.   $$ P(B) = N (B_0, \Sigma_{B}) $$  The conditional posterior distribution for $B$ is proportional to $P(y|B) P(B)$. This is proportional to:  $$ \exp \big((B - B_0)^T \Sigma (B - B_0) + (y - Bx)^T \nabla (y - Bx)\big) $$  I have seen the textbooks mention something called completing the square which as far as I can tell equates to matching like terms. Even though I could work out for scalar variance terms, I am having trouble figuring out how to deal with the precision matrices and how this can be decoupled.   [EDIT]:  So, I tried to make a run with Glen_b's suggestion and came this far:  Original expression without the exponential (I will simplify notation slightly):  $$ (B - B_0)^T \Sigma (B - B_0) + ( y - Bx)^T \nabla (y - Bx) $$ Expanding:  $$ B^T\Sigma B - 2 B_0^T \Sigma B + B_0^T \Sigma B_0 + y^T \nabla y - 2 y^T \nabla B x + (Bx)^T \nabla Bx $$  $$ = B^T(\Sigma + x^T \nabla x)B - 2 (B_0^T \Sigma B + y^T \nabla B x) + C $$  So I am not sure how to make further progress with the second term. I guess I have to make it in the form 2(some_term)B but not sure how that can be done. Im trying to solve the following question         In the second step  where do they get $k!=2^k-1?$ I have a 1TB FAILING hard drive, a brand new 1 TB hard drive, a bootable ubuntu usb, and a working computer.  All I need is a step by step process of how to safely clone as much data as possible from one to the other. NOTE: THE DRIVE IS FAILING.  I know I need to enable multiverse and then install and use ddrescue to complete the task. But everywhere I look online, I can't get a straight path to the task. I know that this can be all done within the terminal and that's what I seek.  How can I do this? Performing Raster Reclassification in QGIS? Is there a way to perform a reclassify of a raster image in QGIS?  In ArcGIS you can do that in Spatial analyst Tools→Reclass→Reclassify  Any ideas? Google Maps API v3, jQuery UI Tabs, map not resizing Forbid links to open new tabs in Google Chrome $TT^*=T^2$, show that $T$ is self-adjoint Let $V$ be an inner product space, finitely generated over $\mathbb{C}$, $T\in \operatorname{End}(V)$ that satisfies $TT^*=T^2$, show that $T$ is self-adjoint.    I know that $TT^*$ is positive so has positive square-root, thus the square root is positive definite. But I don't feel like this is a proof. Can anyone prove it without considering square root? Separate Biblatex bibliographies with newest entry and highest reference number at the top I would like to have a similar biblatex behaviour as described , i.e. separate bibliographies for different publication types, each bibliography should 1) be prefixed with a corresponding label (C for conference publications, J for journals etc), 2) sorted so that the newest entry is at the top (defined by the publication year) and 3) with reference numbers sorted in descending order per bibliography, i.e. the newest entry should have the highest number.  Journal articles ---------------- [J3]    reference from 2017 [J2]    reference from 2016 [J1]    reference from 2015  Conference publications ----------------------- [C4]    reference from 2017 [C3]    reference from 2017 [C2]    reference from 2016 [C1]    reference from 2015   I currently have the following:  \usepackage[backend=biber,         isbn=true,         giveninits=true,         style=numeric,         maxnames=99,         sorting=ydnt,         defernumbers=true,         autocite=superscript]{biblatex}  \subsection*{Journal articles} \begin{refcontext}[labelprefix=J] \printbibliography[type=article] \end{refcontext}  \subsection*{Conference publications} \begin{refcontext}[labelprefix=C] \printbibliography[type=inproceedings]   Separate bibliographies works fine, labelprefix also works as desired, sorting by year in descending order as well. However, if I try the solution mentioned in the above question I get very high reference numbers (in the 500s).  Is the above behaviour possible at all and, if yes, what is the most elegant solution using current biblatex etc.?  Thanks a lot in advance! Positivity of a determinant Why is it better to use "#!/usr/bin/env NAME" instead of "#!/path/to/NAME" as my shebang? Im trying to run the following code  \documentclass[border=10pt]{standalone} \usepackage{pgfplots} \pgfplotsset{width = 7cm, compat = 1.8} \begin{document} \begin{tikzpicture} \begin{axis}[domain = -2:2, domain y = 0:2*pi] \addplot3[contour gnuplot = {output point meta = rawz, number=10, labels=false}, samples = 41, z filter/.code=\def\pgfmathresult{-1.6}] {exp(-x^2) * sin(deg(y))}; \addplot3[surf, samples = 25] {exp(-x^2) * sin(deg(y))}; \end{axis} \end{tikzpicture} \end{document}   and I'm getting the error  Package pgfplots Error: sorry, plot file{Utitlled_contourmp0.table} could not be opened   through a quick search I found out that contour maps require pgfplots and gnuplot to talk to each other. In theory the way to make them interact is adding  !TEX option = --enable-write18   or   %!TEX option = --enable-escape   at the top of the file. Unfortunately this has not worked for me. Any suggestions? Some packages, have a Provides: header. For example, the package postfix on Debian Wheezy has Provides: mail-transport-agent.   The package mail-transport-agent which doesn't exist physically is considered as a "virtual" package.   How can I know, on a Debian based system, if a given virtual package is "installed" (or "provided")? Can I list every "provided" virtual package?  Hint: to list every existing virtual package, installed or not, do: aptitude search "~v" Random integer in VB.NET I need to generate a random integer between 1 and n (where n is a positive whole number) to use for a unit test. I don't need something overly complicated to ensure true randomness - just an old-fashioned random number.  How would I do that? How to force a table into page width? I have the following table:  \begin{table}[htb] \begin{tikzpicture} \node (table) [inner sep=0pt] { \begin{tabular}{ l | l }   {\bf Symptom} &amp; {\bf Metric} \\ \hline Class that has many accessor methods and accesses a lot of external data &amp; ATFD is more than a few\\ Class that is large and complex &amp; WMC is high\\ Class that has a lot of methods that only operate on a proper subset of the instance variable set &amp; TCC is low\\ \end{tabular} }; \draw [rounded corners=.5em] (table.north west) rectangle (table.south east); \end{tikzpicture} \caption{God class symptoms} \label{tbl:god_class} \end{table}   Now I want to force the width of the table to be the same as the \textwidth, either by linewrapping of table text or by scaling. How can I achieve that?