LaTeX, of course, has a protective mechanism that prevents you from doing some stupid things:  \newcommand\a{a} \newcommand\a{b} %% LaTeX Error: Command \a already defined.   Of course, if you know what you're doing, then you can circumvent it with \renewcommand.  However, some commands have their own definition mechanisms:  \newcommand\a{a} \DeclareMathOperator\a{a} %% LaTeX Error: Command \a already defined.   (and there is no \RedeclareMathOperator).  I've been getting around this by doing something awkward like:  \newcommand\a{a} \makeatletter \DeclareMathOperator\@a{a} \let\a=\@a %% \let (and \def) circumvents LaTeX's protection \makeatother   (Of course, the best thing to do would be to delete that original definition, but, in practice, it's in another package that I must include but whose source I do not control.)  However, it occurs to me that a hypothetical \undef command would do the job:  \newcommand\a{a} \undef\a \newcommand\a{b} %% No complaints   Does such a command exist?  If not, is there an easy way to write it?
I thought the way to undo a \def was to define it to \relax, but that does not appear to work.  Also, am not sure why this produces no output if I try to use \def instead of \let in my attempt to do an undef.  \documentclass{article}  \begin{document}  \def\CaseA{}%  \ifdefined\CaseA%     \def\ProcessCaseA{}%     % Do stuff that uses \ProcessCaseA     %\def\ProcessCaseA\relax% no output if use this, and comment next line     \let\ProcessCaseA\relax% no output if comment this, and use above line \fi  % Now do stuff that requires \ProcessCaseA NOT be defined \ifdefined\ProcessCaseA     ERROR: \textbackslash ProcessCaseA is still defined \else     SUCCESS: \textbackslash ProcessCaseA is not defined \fi  \end{document}
Find where java class is loaded from Throughout Blade Runner we see Gaff (Edward James Olmos) making origami figures at various points in the movie. He makes a chicken, matchstick men and at the end of the film there is a unicorn waiting outside Deckard's apartment.    There is a   of  out there regarding the unicorn in particular, and how it indicates that Deckard is a replicant. I think an answer regarding the use of origami in general will be interesting new ground to cover.  Why origami? What does the origami represent in Blade Runner? iPhone makes shutter sound when taking photos despite being on mute Is It Possible to NSLog C Structs (Like CGRect or CGPoint)? I want to be able to debug C structures without having to explicitly type every property that they consist of.  i.e. I want to be able to do something like this:  CGPoint cgPoint = CGPointMake(0,0); NSLog(@"%@",cgPoint);   Obviously the '%@' won't work, hence the question. Should you use a plural verb if you refer to a fraction?     Nine tenths of the pillar have rotted away.   I think has should be used here, but I'm not sure. My neighbor has asked me help with his laptop, an HP with lost power-on password. I tried inserting an Ubuntu cd to format the partition, but well... it doesn't even get there. Any ideas? The version of python2 on my Ubuntu 14.04 machine is Python 2.7.6. How can I upgrade it to the the latest version of Python 2.X? The latest is currently 2.7.11.  I have tried apt-get update/upgrade, but the repository doesn't seem to have the latest version. Packages: graphics vs graphicx Different websites suggest using one of those two packages.  \usepackage{graphicx} \usepackage{graphics}   What are differences between them? Which is better? How is effect precedence determined? I was using  and my opponent has a . I attacked Sylvanas, fearing that the Deathrattle will take control of one Hyena. I feel lucky, because it did not happen.  I want to know if there are some general rules of effect precedence.   Has Blizzard published something about this?  Are there articles teaching about precedence?   Please note, I want guidance about effect precedence in general, not just about Deathrattle. How to determine the cause of MacBook battery not charging? I see that the question &quot;why is my MacBook not charging?&quot; gets asked a lot. The problem is, there are multiple reasons. Possible points of failure are: charger, cable, magsafe connector, DC input board, logic board, battery. (Have I missed any?). What is the best sequence for a user to follow, to diagnose the problem? By way of example, here are the first steps that I usually try:  Make sure the charger is working. Either use your charger on a different Mac, or test a spare charger with your Mac.  Check the connection. There might be gunk in your port that's stopping the connector from lying flat.  Try resetting the SMC and PRAM.  If the computer boots, run Coconut Battery to determine battery status.   This is where I get a bit stuck. For example, I have a machine here that boots fine when plugged in, but not from battery. Disconnecting the MagSafe causes the machine to switch off. Sounds like it's a dead battery, except that Coconut reports the battery as detected, in good condition, but not charging. What steps should I take next? Specifically, I'm asking for a generic algorithm to help determine the source of the fault (preferably without swapping out lots of components one by one)? What is the best way to copy text to the clipboard (multi-browser)? I have tried: function copyToClipboard(text) {     if (window.clipboardData) { // Internet Explorer         window.clipboardData.setData(&quot;Text&quot;, text);     } else {         unsafeWindow.netscape.security.PrivilegeManager.enablePrivilege(&quot;UniversalXPConnect&quot;);         const clipboardHelper = Components.classes[&quot;@mozilla.org/widget/clipboardhelper;1&quot;].getService(Components.interfaces.nsIClipboardHelper);         clipboardHelper.copyString(text);     } }  But in Internet Explorer it gives a syntax error. In Firefox, it says unsafeWindow is not defined. A nice trick without using : Clicking leave closed shows the reopen pop-up Is there a good word for a square-rectangle relationship? Any given square is always a rectangle, but a rectangle isn't necessarily a square, so squares and rectangles have a _ relationship. I've been noticing this sort of thing everywhere ever since I noticed that I didn't know a good word for it. I've been calling it a container relationship because one class of things is contained within a larger class of things. However, a "container" relationship doesn't sound very good and doesn't really convey the meaning on its own. A more elegant word would be helpful.  Edit: A specific definition would be something like: a is always b. b is sometimes a. One adjective for two or more nouns Could we use one adjective for two nouns? Is the following sentence correct?     It has low speed and voltage. I'd like to do some URL rewriting (Why? See .) so that instead of users seeing addresses like   labouseur.com/course-compilers.html    they can instead see and use simply   labouseur.com/course-compilers   (Even better, maybe I should restructure that so that it's courses/compilers.)  I'm using a Linux-based shared hosting service for my website, so I do not have administrative control of the server, but I do have control over .htaccess. The references I've read online seemed less than clear to me, so I'm looking for a little clarity and advice here. When we push a box, the box applies an opposite force on my hand, but why does my hand move with the box as I push the box if the net force of my hand is 0? What is happening? Prove $(x_1+.....+x_n)^2 \leq n(x_1^2 + .....+x_n^2)$ Prove that  $(x_1+\dots+x_n)^2 \leq n(x_1^2 + \dots+x_n^2)$  for all positive integers n and all real numbers $x_1,....,x_n$  I am attempting a proof by induction but wasn't sure if i need the Cauchy-Schwarz Inequality or perhaps another way other than induction to prove this.  Proof   $n=1$ true  assume true for $n=k$  Now for $n= k+1$  $(x_1 + \dots +x_k + x_{k+1})^2 \leq \dots$ I have a corrupt tarball on my hands. My first attempt at recovery went like this:  $ tar --ignore-failed-read --ignore-command-error -xf tarball.tar tar: Skipping to next header tar: Archive contains ‘180738 0’ where numeric mode_t value expected tar: Archive contains ‘0.445647 -9.’ where numeric time_t value expected tar: Archive contains ‘.259273 ’ where numeric uid_t value expected tar: Archive contains obsolescent base-64 headers tar: Archive contains ‘-0.94874’ where numeric gid_t value expected tar: text from a text file is here: implausibly old time stamp 1969-12-31 18:59:59 tar: more text file contents are here: Unknown file type 'p', extracted as normal file tar: Skipping to next header tar: Skipping to next header tar: Exiting with failure status due to previous errors   This didn't extract much from the tarball before erroring out. The exit status is 2 which the tar man page says is a fatal error.  The documentation for "" suggested this:  cpio -F tarball.tar -i -v   This extracted 1.2G of a 1.8G tarball, which is pretty good. It stops with a bunch of garbage entered after the terminal prompt -- it isn't printed to the screen, it's as if I had typed it and didn't hit return yet.  Is there a way to do any better? Is there a way to try and "jump over the bad chunks" of the tarball?  With --ignore-zeros tar seems to be reading through the entire tar file.  tar -R --ignore-failed-read --ignore-command-error --ignore-zeros -xvf tarball.tar [...] block 3670356: ** Block of NULs ** block 3670357: ** Block of NULs ** block 3670358: ** Block of NULs ** block 3670359: ** End of File ** tar: Exiting with failure status due to previous errors   There are a lot of Block of NULs errors so it looks like the contents might be irretrievable. I work in D8, I create a custom module first_module. By modules create a url and display all nodes by *.html.twig file.  Write code in controller.php  public function contentthree() {    $connection = Database::getConnection();    $query = $connection-&gt;select('node', 'n');   $query-&gt;fields('n', ['nid', 'type']);    $groups = $query-&gt;execute()-&gt;fetchAll();    foreach ($groups as $group) {     $events[] = [$group-&gt;nid, $group-&gt;type];   }    return [     '#theme'  =&gt; 'first_module_display',     '#events' =&gt; $events,   ]; }   In *.module  function first_module_theme($existing, $type, $theme, $path) {    return [     'first_module_display' =&gt; [       'variables' =&gt; ['events' =&gt; NULL],       'template'  =&gt; 'first-module-list',     ],   ]; }  function _get_node_details() {    $output = 'Welcome D8';    $output .= 'Node Details';    return $output; }   and create templates first-module-list.html.twig and display data  {%for key, data in events %}  {%for key1, data1 in data %}     {{ data1 }}  {% endfor %}  {% endfor %}   work fine and showing data correct. But, my question is how to call function _get_node_details() and how to render node details in first-module-list.html.twig files? I have just discovered that my local bank, Nordea, has decided to remove the only good thing about their entire operation: the so-called "simplified login" feature on their website, which allows (soon allowed) the customer to log in to a kind of very limited "read-only" mode which basically just allowed you to see your current balance, the last few transactions (limited descriptions) and see whether or not there are any new "customer support messages", but not read those messages, not make any kind of payments, edit accounts, etc.  Now, they will only allow "full" logins, which 100% prevents any kind of automation and requires you to sit with a hardware device and enter numbers into it and then into the webpage before it allows you to see as much as your account balance. Other than being very obnoxious for every customer, it also blocks me and other "advanced" users out from our custom-programmed bots which have always regularly logged in with that "simplified" login method just to regexp out the current balance/new messages and then notify us via whatever mechanism we use privately.  I have previously asked them if they have any kind of JSON/RSS API of any kind, but no. They don't even have as much as e-mail notifications! Nothing except their spyware "smartphone app" which I would never install, nor would I ever allow such a surveillance device to track me 24/7 in the first place. Only by being a registered corporation with special, way more costly account types do you get any kind of "API" access from them, even to do this most basic imaginable task.  Before you tell me to switch banks, the others are at least just as bad (even worse from what I can tell, and for a longer time), and the act of switching banks is practically impossible for me personally.  What I'm asking is if maybe somebody knows of some sort of "hidden standard" or something which all banks in the world support, but don't have documented, for people like me to automate basic things such as knowing my account balance. Needless to say, I have looked for this countless times on their website, asked them about it, and asked other people about it. Nobody seems to know anything, or, if they do, won't tell me.  I know that there are a bunch of "Nordea-supporting" PHP libraries and whatnot on Github, but they are all ancient and even if they were up to date, they were most likely using the same method as I have been using: automating the login process through their "simplified login" mechanism, which is "soon" to be gone. (Probably at new year; they didn't even mention any dates or time frames.)  And yes, I have a Bitcoin wallet and have that fully automated. The problem is that virtually nobody else in the world cares about my Bitcoin, so "switching to Bitcoin" remains a pipe dream which I would be ready to do, but the world clearly isn't.