Why are templates not redefined, why is it all written in the header file?
Why can templates only be implemented in the header file?
Use a specific forwarded key from SSH-agent? Let's say I have a key for Github, along with other keys. I've added lots of keys to my ssh agent (ssh-add -L returns lots of lines) at my home computer A. In my .ssh/config I have set up which key to use with which host, so e.g.  ssh -T -vvv git@github.com 2&gt;&amp;1 | grep Offering   gives  debug1: Offering RSA public key: /Users/doxna/.ssh/id_rsa.github   Only one key is offered, as expected. But then ssh-ing to some host B with ForwardAgent yes and repeating the same command, I get  debug1: Offering RSA public key: /Users/doxna/.ssh/id_rsa.linode2 debug1: Offering RSA public key: /Users/doxna/.ssh/id_rsa.helium debug1: Offering RSA public key: /Users/doxna/.ssh/id_rsa.github   meaning it tries all my keys. This is problematic since only a limited number of keys can be tried before servers return Too many authentication failures. So I tried editing .ssh/config on host B to include  Host github.com   IdentityFile /Users/doxna/.ssh/id_rsa.github   IdentitiesOnly yes   but then I get no key offerings, but rather  debug2: key: /Users/doxna/.ssh/id_rsa.github ((nil))   which I guess means that the key was not found(?) And after all, the key is located at my home computer A, not host B, so the question is how to refer to it at host B? Hope I managed to explain the question. Beamer: Blackboard theme and overlays I am currently preparing my beamer presentation for my PhD defense.  I took the example at the url  to get a black board style presentation.  This template includes a short script which uses a random-generator to randomly scatter dust-trails on the black background to mimic chalk traces (see MWE below).  The thing is that parallel to that, I am also using overlays to uncover my slide layout by layout. The script is executed each time I am using a layout command which slows down the compilation quite substantially. I am not so familiar with control statements in latex, so here is my question:  How can-I modify this script for the background to be refreshed only when the slide is over, and not after each layout command?  Remarks:  1) I am using the Augie font, but I didn't included it in the MWE so that it can be compiled more easily  2) In case, it should make a difference I am also using the \begin{textblock*} \end{textblock*} environment from the textpos package to position text on the slide.  Here is my MWE:   \documentclass[10pt,mathserif]{beamer}  \usepackage[francais,english]{babel} \usepackage[utf8] {inputenc} %for ISOlatin1 (8859-1) sources \usepackage[T1] {fontenc}      %for polices DC 8bits   %%%Fancy fonts %\usepackage{emerald} %\usepackage{eulervm} %%%  %%Extra packages \usepackage{amsmath} \usepackage{amsfonts} \usepackage{tikz} \usetikzlibrary{arrows,shapes} \usepackage[absolute,overlay]{textpos}    %set text colors for different objects \setbeamercolor{frametitle}{fg=white} \setbeamercolor{structure}{fg=white} \setbeamercolor{normal text}{fg=white} \setbeamercolor{alerted text}{fg=white} \setbeamercolor{example text}{fg=white}   %%Black background \setbeamercolor{background canvas}{bg=black}    %%%%%%%%%%%%%%%%%%%%%% %%%%%Script: Random Dust Trails%%%%%%%%%%%%%%% \pgfmathsetseed{\number\pdfrandomseed} % seed for random generator \setbeamertemplate{background}{     \begin{tikzpicture}         \useasboundingbox (0,0) rectangle (\the\paperwidth, \the\paperheight);        \foreach \i in {1,...,30} {             \pgfmathsetmacro{\x}{random(0,10000)/5000-1}%             \pgfmathsetmacro{\y}{random(0,10000)/10000-0.1}%             \pgfmathsetmacro{\r}{random(0,10000)/1000-5}%             \rotatebox{\r}{                 \pgftext[at=\pgfpoint{\x\paperwidth}{\y\paperheight}, left, base]{\includegraphics[width=\textwidth]{paintstroke.png}}             }         };      \end{tikzpicture} } %%%%%%%%%%%%%%%%%%%%%%  %%No navigation bar \setbeamertemplate{navigation symbols}{}  \begin{document}      \begin{frame}          \begin{itemize}             \item&lt;1-&gt; bla slide 1             \item&lt;2-&gt; blu slide 1             \item&lt;3-&gt; blub slide 1         \end{itemize}      \end{frame}  %%I want the background to be refreshed with the Dust Trails script only at the end of the frame          \begin{frame}          \begin{itemize}             \item&lt;1-&gt; bla slide 2             \item&lt;2-&gt; blu slide 2             \item&lt;3-&gt; blub slide 2         \end{itemize}      \end{frame}  \end{document}   This is my first post, so please be kind if I did something illegal on the formatting of the message ;-).  Thanks in advance,  Yannick First of all, I know that light does indeed travel slower in a medium like air or water, but that's because the photons are bouncing off of the medium's particles and in different directions so the light beam as a whole is slowed down (or at least that's the classical explanation I've read somewhere).  But my question is about light traveling freely in the vacuum. What if an astronaut during a spacewalk switches on a flashlight towards the opposite direction he is moving. Will that light travel slower than normal?  If not, is there another way to make light move slower? For example, can you make a beam of light move so slow that you can visually perceive it being affected by gravity? Semicolon or dash? International TLD's vs. duplicate content I currently work at a pretty big website that has visitors from around the globe. My job is to help out on the SEO, and one thing we've been discussing lately is the use of international TLD's. The ones we use range between:   (partly) translated websites like .es and .de that serve most of the content in the country's language non-translated (english) websites for non-english languages (due to a lack of translations) like .ro and .cz english websites for english speaking countries with localized TLD's (.co.nz, .co.uk)   On one hand I really have the feeling this is causing a lot of duplicate content, especially for the last two categories of TLD's.   On the other hand though it seems a lot like country-specific TLD's tend to score a lot better in that country's Google. Would it be advisable to keep on using these domains, or should we canonicalize them all to the .com version? How to auto-start unprivileged lxc containers? On Ubuntu 14.04, I have created an unprivileged container that I can manually start and stop.  But I would like this to start and stop along with the system.  I have added the following to the container's configuration:  lxc.start.auto = 1 lxc.start.delay = 5   However, the system scripts don't seem to pick unprivileged containers.  There is  related to this on linuxcontainers.org, but the solution seems to be restricted to root user.  Is there a clean way to do this for a non-root user (with root user's consent)? latex table border dont appear / to big / to small still working on that table. Here's my new question reguarding the table borders:  It appears, that i do something wrong setting boarders. Here is my code, and a screenshot:  \documentclass{article} \usepackage{multirow} % Used for the vertical cells \usepackage{rotating} % Used for the vertical cells  \usepackage{xcolor} % Used for cell-colors \usepackage{colortbl} % Used for cell-colors  \usepackage[a4paper]{geometry}% Used to set the pdf margins manually \newgeometry{left=2cm,bottom=0.1cm}  \definecolor{grey}{HTML}{F2F2F2} % Define grey for the cells \definecolor{red}{HTML}{FF0000} % Define red for testing  \begin{document} \scriptsize % Use a small font size  \begin{tabular}{|p{0.6cm}|p{0.6cm}|p{0.6cm}|p{0.6cm}|p{0.6cm}|p{0.6cm}|p{0.6cm}|p{0.6cm}|p{0.6cm}|p{0.6cm}|p{0.6cm}|p{0.6cm}|p{0.6cm}|p{0.6cm}|p{0.6cm}|p{0.6cm}|p{0,6cm}|}  \cline{10-17}  \multicolumn{9}{|c|}{} &amp; \multicolumn{2}{p{\dimexpr (0.6cm)*2+2\arrayrulewidth+2\tabcolsep\relax}|}{\cellcolor{grey}Work to retired ratio} &amp; \multicolumn{4}{p{\dimexpr (0.6cm)*4+1\arrayrulewidth+2\tabcolsep\relax}|}{Health care sizing (per thousand)} &amp; \multicolumn{2}{p{\dimexpr (0.6cm)*2+1\arrayrulewidth+2\tabcolsep\relax}|}{\cellcolor{grey}Inverse dependency ratio}\\\cline{3-9}  \multicolumn{2}{|c|}{} &amp; \multicolumn{4}{c|}{\cellcolor{grey}Population (mio.)} &amp; \multicolumn{3}{c}{Workforce (1000)}  &amp; \multicolumn{2}{|c|}{\cellcolor{grey}} &amp; \multicolumn{2}{l|}{Physicians by} &amp; \multicolumn{2}{l}{Nurses by} &amp; \multicolumn{2}{|l|}{\cellcolor{grey}Old agers by}\\\hline  \multicolumn{2}{|c|}{} &amp; \begin{sideways}\cellcolor{grey}\parbox{4cm}{Overall}\end{sideways} &amp; \begin{sideways}\cellcolor{grey}\parbox{4cm}{Young age}\end{sideways} &amp; \begin{sideways}\cellcolor{grey}\parbox{4cm}{Working age}\end{sideways} &amp; \begin{sideways}\cellcolor{grey}\parbox{4cm}{Old age}\end{sideways} &amp; \begin{sideways}\parbox{4cm}{Overall}\end{sideways} &amp; \begin{sideways}\parbox{4cm}{Physicians (Proj: 2025)}\end{sideways} &amp; \begin{sideways}\parbox{4cm}{Nurses (Proj: 2030)}\end{sideways} &amp; \begin{sideways}\parbox{4cm}{\cellcolor{grey}Working age by Old age}\end{sideways} &amp; \begin{sideways}\parbox{4cm}{\cellcolor{grey}Work force by Old age}\end{sideways} &amp; \begin{sideways}\parbox{4cm}{Workforce}\end{sideways} &amp; \begin{sideways}\parbox{4cm}{Working age}\end{sideways} &amp; \begin{sideways}\parbox{4cm}{Workforce}\end{sideways} &amp; \begin{sideways}\parbox{4cm}{Working age}\end{sideways} &amp; \begin{sideways}\parbox{4cm}{\cellcolor{grey}1 physicians}\end{sideways} &amp; \begin{sideways}\parbox{4cm}{\cellcolor{grey}1 nurse}\end{sideways}\\\hline  \multicolumn{2}{|l}{USA} &amp; \multicolumn{4}{l}{\cellcolor{grey}} &amp; \multicolumn{3}{l}{} &amp; \multicolumn{2}{l}{\cellcolor{grey}} &amp; \multicolumn{4}{l}{} &amp; \multicolumn{2}{l|}{\cellcolor{grey}}\\\hline  1990/1 &amp; &amp; 248,6 &amp; 71,3 &amp; 146,1 &amp; 31,2 &amp; 127.500 &amp; 615,4 &amp; 1491,6 &amp; 4,68 &amp; 4,09 &amp; 4,83 &amp; 4,21 &amp; 11,70 &amp; 10,21 &amp; 50,7 &amp; 20,9\\\hline  1 &amp; 2 &amp; 3 \\\hline  \end{tabular}  \end{document}     On 1 the Top border of Population is not visible although i did used \\\cline{3-9}\cline{12-17} on that line.  In 2 both borders are pushed a bit to the right for no reason i can see.  And in 3 again the top borders are not visible despite using \cline{10-17} on that line. What did i do wrong?  Thanks! In the inbox of the app, there is no way to differentiate between comments and answers as is in the global inbox of the website.  Could this be added? How does IPv4 Subnetting Work? This is a  about IPv4 Subnets.      Related:               How does Subnetting Work, and How do you do it by hand or in your head?  Can someone explain both conceptually and with several examples? Server Fault gets lots of subnetting homework questions, so we could use an answer to point them to on Server Fault itself.   If I have a network, how do I figure out how to split it up? If I am given a netmask, how do I know what the network Range is for it? Sometimes there is a slash followed by a number, what is that number? Sometimes there is a subnet mask, but also a wildcard mask, they seem like the same thing but they are different? Someone mentioned something about knowing binary for this? What is "summoning sickness" and how does it affect my creatures? Note: this is intended to be a canonical question about summoning sickness.  "Summoning sickness", broadly, is the rule that stops you from attacking or paying {T} costs with a creature that you just played. But how exactly does it work? How does it interact with other rules and effects?  For example, if I'm trying to figure out how a creature is affected:   Does the status matter (tapped/untapped, face down/face up, etc.)? What if it came into play, but I didn't cast it? What if it's a token? What if it was on the battlefield when my turn started, but it wasn't a creature? What if it stops being a creature? What if it's a creature and also another card type? What if it's a double-faced card that just transformed? What if it changes control? What if it's a copy of another creature? Which of the creature's activated abilities can I use? Are any of its other abilities affected? Can I tap the creature to pay a cost that is not a {T} cost?   (These examples are primarily taken from questions about summoning sickness that have already been asked on the site) CloudPagesURL() value not showing in HTML I am trying to pass the email value from a data extension to HTML. I am using the CloudPagesURL() in my email in attempt to grab the subscriber's email.  Here is my code syntax that I am attempting to use:  Email Code:  &lt;p&gt;&lt;a title="MyPage" href="%%=RedirectTo(CloudPagesURL(505,'Email Address',@EmailAddress))=%%" alias="ThisAlias" conversion="false"&gt;Click to unsubscribe page 505&lt;/a&gt;&lt;/p&gt;   CloudPage AMPScript Code:  %%[  VAR @emailAddress  SET @emailAddress = RequestParameter("emailaddr")  ]%%   Cloudpage HTML Code:  &lt;td width='155' valign='bottom'&gt;&lt;input type='text' name='Name1' value='%%=v(@emailAddress)=%%' id='Name1' /&gt;&lt;/td&gt;   Any reason as to why this doesn't work? My syntax might just be wrong or I might be using the CloudPagesURL() function incorrectly. Calculate daily sums using python pandas "IllegalFormatConversionException: d != java.lang.String" when padding number with 0s? If $\gcd(a,b)=1$ and $a$ and $b$ divide $c$, then so does $ab$ Cumulative Sum without Script What is the resolution of tapping a blocking creature? Let's say I have declared a blocker during the correct phase and during the activate abilities step I choose to tap the blocker to use its ability.  All the abilities resolve and now we move to the declare damage step.  I believe the resolution is that the attacking creature remains blocked and that it deals damage to my blocker; however, the blocker does not deal damage to the attacker.  How would this change if the blocker had first strike? How would this change if the blocker was sacrificed? I just went to install Java 8 on my ancient laptop that runs Windows XP SP3.  Java pops up a message:     Java 8 requires a newer version of Windows. You may continue with the installation, but for Java to work as specified we recommend upgrading your computer's operating system.   Will Java fail to work properly on Windows XP? Or is this just Oracle trying to be secure? Search [tag1] OR [tag2] Is there a way to search questions that are tagged with either tag1 or tag2?  Actually, I would like the general filter,      ([tag1] AND [tag2], ...) OR ([tag3]   AND [tag4], ...) OR ...   And even     [tag1] AND ([tag2] OR [tag3])   I need that because I'm looking for interesting questions and I have to search for each tag separately. Stack Overflow in ES, PT, RU, JP have mixed-language descriptions grouped bar chart with pgfplots