excluding an internal element while slicing
Understanding slice notation
How to launch terminal on login How could I get the terminal to be launched once I have logged in, so that typing commands is much simpler? Any open subset of $\Bbb R$ is a countable union of disjoint open intervals Let $U$ be an open set in $\mathbb R$. Then $U$ is a countable union of disjoint intervals.    This question has probably been asked. However, I am not interested in just getting the answer to it. Rather, I am interested in collecting as many different proofs of it which are as diverse as possible. A professor told me that there are many. So, I invite everyone who has seen proofs of this fact to share them with the community. I think it is a result worth knowing how to prove in many different ways and having a post that combines as many of them as possible will, no doubt, be quite useful. After two days, I will place a bounty on this question to attract as many people as possible. Of course, any comments, corrections, suggestions, links to papers/notes etc. are more than welcome. Contextually grey out panel element in python 2.8 I have a panel with split column.  In the 2nd row is 3 boolean variables. I want to grey out the 2nd and 3rd option by default. I want the 2nd to be changeable if 1st is true, and 3rd to be changeable if both 1 and two are true. I've read something about "poll()" but not how to actually use it, or set conditions. Physics should only be enablable if singleMesh, and destructable only if physics enabled.      # Create two columns, by using a split layout.     split = layout.split()      # First column     col = split.column()     col.label(text="Building Size:")     col.prop(bpy.context.scene.user_vars, 'buildingHeight')     col.prop(bpy.context.scene.user_vars, 'buildingWidth')     col.prop(bpy.context.scene.user_vars, 'buildingDepth')      # Second column, aligned     col = split.column()     col.label(text="Dynamics:")     col.prop(bpy.context.scene.user_vars, 'singleMesh')     col.prop(bpy.context.scene.user_vars, 'enablePhysics')     col.prop(bpy.context.scene.user_vars, 'destructable_Building')  #EDIT This is what the specific solution to my example looks like. col = split.column() col.label(text="Dynamics:") col.prop(vars, 'singleMesh') sub = col.row() sub.enabled = vars.singleMesh sub.prop(vars, 'enablePhysics') sub = col.row() sub.enabled = vars.enablePhysics sub.prop(vars, 'destructable_Building') Show that the cardinality of $\mathbb N$ is the same as the cardinality of $\mathbb N \times \mathbb N$ Show that $| \mathbb N | = | \mathbb N \times \mathbb N |$, i.e., the cardinality  of $\mathbb N$ is the same as the cardinality of $\mathbb N \times \mathbb N$.   How do I show it using the Fundamental Theorem of Arithmetic and the Schröder–Bernstein Theorem? How do I iterate over cin line by line in C++? new array.sty and colortbl.sty incompatibility? I just upgraded my texlive distribution and can no longer insert space in table rows using \\[x pt] syntax when colortbl is loaded.  It seems that recent changes to array.sty might be the problem as this is the only package to change recently.  Can anyone suggest a workaround?  MWE  \listfiles \documentclass{article} \usepackage{colortbl} \begin{document} \begin{tabular}{l}   \hline   No space below with \texttt{colortbl.sty} loaded. \\[10mm]   \hline \end{tabular} \end{document}   File versions in use:   article.cls    2014/09/29 v1.4h Standard LaTeX document class   size10.clo    2014/09/29 v1.4h Standard LaTeX file (size option) colortbl.sty    2012/02/13 v1.0a Color table columns (DPC)    array.sty    2018/04/07 v2.4g Tabular extension package (FMi)    color.sty    2016/07/10 v1.1e Standard LaTeX Color (DPC)    color.cfg    2016/01/02 v1.6 sample color configuration   pdftex.def    2018/01/08 v1.0l Graphics/color driver for pdftex Normally while searching using grep, the command I was using was this:  grep -nri "String"   whereas most of my colleagues do this:  grep -nri "String" *   What does the latter do (the * part)? How does body fat leave your body? So I know that it’s not from tears or sweat because they are composed of mainly water and sodium, it’s not from going poo or pee as poo and pee are made of the parts of food that supply your body with no nutrients and your body also doesn’t “burn body fat” because there is a theory that no matter is ever destroyed so it’s none of those but another thing is it’s not your hair, ear wax, finger nails or anything of that sort because people can lose over 17 pounds in 3 months but you can’t build up that amount of hair , ear wax or whatever else in three months so how does body fat leave your body How can timelapse sequences be shot without in-camera support? How can timelapse sequences be shot without having in-camera support for it?  Which third-party tools are recommended? Is it possible to install an old version of Mac OS on a new Mac? When I get an idea for something I'd like to make in Blender, I hit up Google for specifics, then blender SE when I get stuck.   I'm very overwhelmed by the immensity of Blender and I'm a little afraid that this self-directed approach is going to lead me to develop bad habits. Is there a "best practice" way of learning to use Blender? How can I bootstrap? How can I bootstrap Drupal 8 from an external script?  This an example script from the .  require_once __DIR__ . '/vendor/autoload.php'; use PhpAmqpLib\Connection\AMQPStreamConnection;  $connection = new AMQPStreamConnection('localhost', 5672, 'guest', 'guest'); $channel = $connection-&gt;channel(); $channel-&gt;queue_declare('task_queue', false, true, false, false); echo " [*] Waiting for messages. To exit press CTRL+C\n"; $callback = function ($msg) {   echo ' [x] Received ', $msg-&gt;body, "\n";   sleep(substr_count($msg-&gt;body, '.'));   echo " [x] Done\n";   $msg-&gt;delivery_info['channel']-&gt;basic_ack($msg-&gt;delivery_info['delivery_tag']); };  $channel-&gt;basic_qos(null, 1, null); $channel-&gt;basic_consume('task_queue', '', false, false, false, false, $callback);  while (count($channel-&gt;callbacks)) {   $channel-&gt;wait(); }  $channel-&gt;close(); $connection-&gt;close();   Within a worker script like this, I need to be able to create nodes.  How can I bootstrap Drupal 8 in this script?  ? and  bootstraps passing a fake request to the kernel, which to me looks like a work-around.  In Drupal 7 you could do something like this, apparently.  // Bootstrap Drupal. include_once './includes/bootstrap.inc'; drupal_bootstrap(DRUPAL_BOOTSTRAP_FULL); When should I use mmap for file access? POSIX environments provide at least two ways of accessing files.  There's the standard system calls open(), read(), write(), and friends, but there's also the option of using mmap() to map the file into virtual memory.  When is it preferable to use one over the other?  What're their individual advantages that merit including two interfaces? Is there a term for the moment when a lot of users visit/log onto your website at the same time? Is there a term for the moment when a lot of users visit/log onto your website at the same time? I am currently developing a website which is going to take some time to finish. I need to move some 'stuff' to production frequently, while maintaining a under construction status. My front page will clearly mention that my website is under construction.  I know crawlers will access my URL before I am ready to go live. Should I tell them my site is under construction (no need to index)? If yes how?  P.S.: Eventually, I am ok to let them see my under construction front page. Having trouble setting up a nginx web server on Amazon EC2 Re-number a list when a new entry is inserted What's the difference between Normalization and Standardization? Outline around text on CMYK black background in Photoshop I'm trying to make a document with one color black  (c:0,m:0,y:0,k:100) background with red text on it. However in CMYK the text has this weird grey white-ish edge. In RGB it doesn't show but in CMYK it shows. I'm wondering will this show when printing or do I need to use different methods? ie. using rich black etc.  Here's the RGB and CMYK comparison Proving that either $2^n-1 $ or $ 2^n+1$ is not prime