Display of dates/times in ISO 8601 format in Files (Nautilus)
How to show full date and time in Nautilus/Files 3.6+ list view?
Archive by Year How to normalize my db schema for a quiz application? I am putting together a quiz application.   (I'm calling each quiz a "challenge")  I have a "challenge" table and a "challenge_question" table which is pretty straightforward.  challenge table: id name num_questions (I want to randomize and only display a certain number of Qs per each challenge)  challenge_question table: id challenge_id question (text of the question) required (some questions will be required to be displayed per each challenge) question_type (here I indicate what type of question: Mult. choice, T/F, Ordering, or Fill-in-the-blank)   Where I'm having trouble in normalization is with the types of question options:  Multiple choice, true/false, ordering, and fill-in-the-blank. I wonder, should I have a separate table for each type of challenge-question-option? Or is it possible to combine these into one somehow..  If I combined all possible options into a single table, it might look be something like this  challenge_options table: id challenge_question_id option (text field, can be used for both multiple choice and for fill-in-the-blank style questions) is_true (boolean field for true/false questions) is_correct (boolean, used to determine multiple choice answer) ordering_option_1  ordering_option_2 ordering_option_3 ordering_option_4 (these ordering fields would store the correct sequence of an ordering style of question)   This really strikes me as less than ideal.  Actually, I don't see how the ordering_options would work out correctly at all.  Wouldn't I need to have each of those be a separate option?  Surely there must be a better way.  Any suggestions/criticisms or alternate approaches? Independent Edit/Object mode in splitscreen When I split screen in two and switch Edit/Object mode, they both change. How to change just one? The intention here is:  use one to modelling with numkey view with transparent wireframe and the other to see the progress in perspective, with solid mesh I'm looking for an algorithm that sorts strings similar to the way files (and folders) are sorted in Windows Explorer. It seems that numeric values in strings are taken into account when sorted which results in something like  name 1, name 2, name 10   instead of  name 1, name 10, name 2   which you get with a regular string comparison.  I was about to start writing this myself but wanted to check if anyone had done this before and was willing to share some code or insights. The way I would approach this would be to add leading zeros to the numeric values in the name before comparing them. This would result in something like  name 00001, name 00010, name 00002   which when sorted with a regular string sort would give me the correct result.  Any ideas? I'm heading to India next week and have a connection in Munich, Germany. I made the mistake of booking a flight with only an hour and a half layover (freaking out!) and I'm wondering if I'll have to go through customs in Munich or if I can pass right on through. Deriving curvature formula How do you derive the formula for unsigned curvature of a curve $\gamma (t) = (x(t), y(t)$ which is not necessarily parameterised by arc-length.   The formula given is $$|\kappa (t)| = \left|\frac{x'' y' - y'' x'}{((x')^2 + (y')^2)^{3/2}}\right|$$  All the definitions of curvature in my notes give it in terms for an arc-length parameterisation $T'(s) = \kappa(s) N(s)$. This is apparently meant to be 'easily derivable', am I missing something? Why xargs can't work with tail -f? I want tail -f /var/log/syslog | grep it with pattern "arpwatch" and send every line to myself via jabber: xmpp username@jabber.server using xargs  tail -f /var/log/syslog | grep arpwatch | xargs sendxmpp username@jabber.server   no working.  but tail  /var/log/syslog | grep arpwatch | sendxmpp username@jabber.server   works well.  I think it's some fundamental thing about xargs and tail -f that I don't understand. com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure Downgrading from Safari 12 (beta) to Safari 11 Installing Safari beta version is apparently only possible by replacing the builtin Safari version. In this case version 11.1.2 with 12. If beta version does not work, gives too much trouble or is just unpleasant:  How do we downgrade to an official stable version, currently Safari 11.1.2 for 10.12.6 Sierra?  I tried to restore everything relating to 11.1.2 from a backup (going by what is found that is in the installer package), I located and re-applied the 11.1.2_Sierra.pkg. Yet Safari now refuses to work entirely.   Crashed Thread:        3  Dispatch queue: com.apple.SafariCore.RemotePlistController.internalQueue  Exception Type:        EXC_CRASH (SIGABRT) Exception Codes:       0x0000000000000000, 0x0000000000000000 Exception Note:        EXC_CORPSE_NOTIFY  Application Specific Information: *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[_NSPlaceholderData initWithContentsOfURL:options:error:]: nil URL argument' terminating with uncaught exception of type NSException abort() called   Is there any way around re-installing the entire system? Best way to randomize an array with .NET What is the best way to randomize an array of strings with .NET? My array contains about 500 strings and I'd like to create a new Array with the same strings but in a random order.  Please include a C# example in your answer. Is there a tag in HTML that will only display its content if JavaScript is enabled? I know &lt;noscript&gt; works the opposite way around, displaying its HTML content when JavaScript is turned off. But I would like to only display a form on a site if JavaScript is available, telling them why they can't use the form if they don't have it.  The only way I know how to do this is with the document.write(); method in a script tag, and it seems a bit messy for large amounts of HTML. How to unzip a zip file from the Terminal? Just downloaded a .zip file from the internet. I want to use the terminal to unzip the file. What is the correct way to do this? What if 'kill -9' does not work? I have a process I can't kill with kill -9 &lt;pid&gt;. What's the problem in such a case, especially since I am the owner of that process. I thought nothing could evade that kill option. Creating files in C++ Get name of caller function in PHP? I find I have to scroll a lot to move the text of my page compared to Windows where I can choose the speed of the mouse wheel.   Does Ubuntu have a similar utility and if so how can I access it? (This is on NT based Windows like 2000, XP, Vista, 7)  On the command-line, the percentage characters are ignored:  wget "http://www.justitie.nl/images/Handleiding%20voor%20verwerkers%20persoonsgegevens_tcm34-3940.pdf"   So it correctly downloads this file (each %20 becomes a space):  "http://www.justitie.nl/images/Handleiding voor verwerkers persoonsgegevens_tcm34-3940.pdf"   But inside a batchfile, all the %20 are being interpreted as expanding parameter 2 (which is empty) resulting in this file to get downloaded (each %20 becomes 0):  "http://www.justitie.nl/images/Handleiding0voor0verwerkers0persoonsgegevens_tcm34-3940.pdf"   Is there a way to circumvent the percentage parameter expansion?  --jeroen Do stone quarries respawn in Hearthfire? Please do not close this as a duplicate unless you can remove the “status-completed” tag from the  (because it’s obviously not been completed).  Steps to reproduce:   Have someone post an answer. Downvote the answer. Have the someone edit the answer within the initial 5 minutes of the answer’s existence. Try to undo the downvote more than 10 minutes later.   You cannot undo the downvote. I have no idea how to find this integral:  $$\int_0^1\frac{(x-x^2)^4}{1+x^2}\ dx\ ?$$  Any help would be appreciated. Thanks in advance.