$\{x: 2x^2\cos(1/x) \le 1\} \cup \{0\}$ is complete.
whether they are complete metric space
$ not defined using jQuery in WordPress Why is there a big delay after entering a wrong password? I notice a weird (well, according to me) thing about passwords. For example, if I type an incorrect password during login, there will be a few seconds' delay before the system tells me so. When I try to sudo with a wrong password I would also have to wait before the shell says "Sorry, try again".  I wonder why it takes so long to "recognize" an incorrect password? This has been seen on several distributions I use (and even OSX), so I think it's not a distribution specific thing. How can I get my external IP address in a shell script? So I had 20+ Pokemon on my account and today when I tapped on the app, it brought me back to the original screen when you first start playing. My friend who signed up tested using my username when she first started and my username was unavailable, meaning the account still exists. I don't have the password for the account, but I do have the email. So I wanted to know if it was possible to log back into an account? Using apostrophes correctly I've read a great article about the . But there are still some points that are unclear.  Why do we say...   school project but not school's project? car service but not car's service or even cars' service (plural form)? apostrophe usage but not apostrophe's usage or apostrophes' usage? Is there a way to add a timer to a Beamer presentation? Loop doesn't see value changed by other thread without a print statement Displaying world country shapefiles centered on Pacific Ocean using Robinson or Miller Cylindrical projection in QGIS? I wish to display a map in QGIS (world country shapefiles) showing all countries but centered on the Pacific area.   I am not familiar with Proj4, so is there any way this can be done in QGIS? Solve for $x$: $2^x=4x$ Given that $x$ is a positive integer. By using methods of trial and error as well as plotting two lines: $y=2^x$, $y=4x$ on a graph and find their intersection point, we can easily solve for $x$ which is equal to 4. However, I do not know how to solve this using only equation. Can anyone help me? Why is accuracy not the best measure for assessing classification models? This is a general question that was asked indirectly multiple times in here, but it lacks a single authoritative answer. It would be great to have a detailed answer to this for the reference.  , the proportion of correct classifications among all classifications, is very simple and very "intuitive" measure, yet it may be a . Why does our intuition misguide us here and are there any other problems with this measure? Has drupal abandoned drush? I've been away from drupal for 2-3 years. I just came back around and installed drush via composer () and now every time I try to use drush I get a message telling me that I should be using composer:  ~/sites/d7 $ drush version  Drush version : 9.0-dev-gd4a3872 ~/sites/d7 $ drush dl drupal-7.x  [notice] dl has been deprecated. Please build your site using Composer. Add new projects with composer require drupal/[project-name]. Use https://www.drupal.org/project/composer_generate to build a composer.json which represents the the enabled modules on your site.   I downloaded drupal 8 following these , but when I try to use drush in that project I get this message:  ~/sites/cfbtv/web $ drush dl devel This codebase is assembled with Composer instead of Drush. Use `composer update` and `composer require` instead of `drush pm-updatecode` and `drush pm-download`. You may override this error by [error] using the --pm-force option.   Is there something wrong with my local env, or is drush a thing of the past now? How to Join Games with Minecraft Pocket Edition 0.7 Why Re-throw Exceptions? I've seen the following code many times:  try {     ... // some code } catch (Exception ex) {     ... // Do something     throw new CustomException(ex);      // or     // throw;      // or     // throw ex; }   Can you please explain the purpose of re-throwing an exception? Is it following a pattern/best practice in exception handling? (I've read somewhere that it's called "Caller Inform" pattern?) Trouble with batch conversion of .png to .pdf using convert When I'm using rendered viewport it initially takes a while before rendering starts, but once it does, I can freely move around and rendering a new view happens almost instantaneously. When on the other hand I'm rendering a movie, for each frame Blender takes a significant amount of time before rendering even starts, usually doing the following:  Synchronizing object, Updating images, Updating meshes, Updating Scene BVH, Packing BVH,  Why does it do this? And is it possible to disable this to increase movie rendering speed? References to a comment on a deleted answer can break Stack Exchange JS For the following URL, JavaScript breaks:  https://stackoverflow.com/questions/16356382/splitting-a-braces-grouped-string-in-python/16356421?noredirect=1#comment23433042_16356421   This is a link to a , the answer I can see as a 10K+ user (although users &lt;10k ).  With Chrome (26, Mac OS X) the console sez:  Uncaught TypeError: Cannot call method 'replace' of undefined   for line 83 of full.js.  Firefox (20, Mac still), the web console spits out:  [12:48:28.459] TypeError: c.attr(...) is undefined @ http://cdn.sstatic.net/js/full.js?v=c9131e40e3fb:83   Safari (6.0.4 on, you guessed it, Mac OS X) has this to complain about:  TypeError: 'undefined' is not an object (evaluating 'c.attr("id").replace')   for line 83 of full.js.  Because of this, the Answer text box on Stack Overflow is lacking all niceties such as an actual WMD editor.  If you remove the hash reference #comment23433042_16356421 from the end of the URL, things work again. Removing the ?noredirect=1 query parameter makes no difference. Is a quotient group a subgroup? Is a quotient group a subgroup?   I am trying to solve the question below, and if the answer to above is "yes," then my proof will follow below.   I am trying to prove that a cyclic group G, has a cyclic quotient group G/N.  Where N is a normal subgroup.  A SUBGROUP OF A CYCLIC GROUP IS CYCLIC.  By   So if   (1) G is cyclic   (2) G/N is a subgroup   (3) G/N is a cyclic subgroup   (4) The Quotient group G/N is cyclic   I am unsure about my reasoning in step (2), Is this a valid assumption? Shortcut for "null if object is null, or object.member if object is not null" Need to proof by induction (calculus1 n and n+1) The following C++ code uses a ifstream object to read integers from a text file (which has one number per line) until it hits EOF. Why does it read the integer on the last line twice? How to fix this?  Code:  #include &lt;iostream&gt; #include &lt;fstream&gt; using namespace std;  int main() {     ifstream iFile("input.txt");    // input.txt has integers, one per line      while (!iFile.eof())     {         int x;         iFile &gt;&gt; x;         cerr &lt;&lt; x &lt;&lt; endl;     }      return 0; }   input.txt:  10   20   30   Output:  10   20   30   30   Note: I've skipped all error checking code to keep the code snippet small. The above behaviour is seen on Windows (Visual C++), cygwin (gcc) and Linux (gcc).