Which way do electrons transfer?
How do that charge gets transferred while rubbing?
How fill face between irregular curves? Hello Blender Stack Exchange,  I am trying to fill a face between 4 surfaces. Two are straight edges and two are a curved line made up of short vertices that came from a SketchUp export.  The problem: I select the vertices on the top and bottom and fill the hole. It creates a strange face that ruins the curve. I would prefer it create some sort of complex curve. I want it to be smooth.  Images attached to better explain. Possessive 's for things Comma after a coordinating conjunction preceding a parenthetical at the start of the sentence Why wget doesn't verify SSL certificates? I have a problem with my Fedora 8 installation. It looks that wget doesn't know how to verify SSL certificates any more. It's strange because I have another Fedora 8 box which I believe has the same configuration and it works!   How can I make it work without using --no-check-certificate switch?  This is a sample output:  wget https://www.google.com --2011-09-23 00:11:13--  https://www.google.com/ Resolving www.google.com... 74.125.230.146, 74.125.230.147, 74.125.230.148, ... Connecting to www.google.com|74.125.230.146|:443... connected. ERROR: cannot verify www.google.com's certificate, issued by `/C=ZA/O=Thawte Consulting (Pty) Ltd./CN=Thawte SGC CA':   Unable to locally verify the issuer's authority. To connect to www.google.com insecurely, use `--no-check-certificate'. Unable to establish SSL connection.   EDIT  I have this file /etc/pki/tls/certs/ca-bundle.crt file and when I run wget with --ca-certificate switch pointing to this file everything goes fine. Where should this file be placed so that I don't need to use the switch?  BTW: curl and links work fine, but lynx also complains: "SSL error:unable to get local issuer certificate" so this is not only wget's issue... Bluetooth indicator disappears on turning off bluetooth Everytime I turn off my bluetooth, the indicator icon in the system tray disappears, as opposed to just greying out as expected. Next time I need to go to the settings select bluetooth to turn it on, which makes the indicator to reappear.  Is there anyway I can make the indicator icon not disappear but stay greyed out when not in use? I was reading a review of 5e game play  from our RSS Feed. And in it he makes an observation about a strange rule:     Weird rule thing. You recover half your level in hit dice during a   long rest, which means level 1 characters never recover hit dice.   That didn't make sense to me, and so I double checked the long rest rule and it reads:     At the end of a long rest, a character regains all lost it points.   The  character also regains spent Hit Dice, up to a number of dice   equal to half of the character’s total number of them. For example, if   a  character has eight Hit Dice, he or she can regain four spent Hit   Dice upon finishing a long rest.   And of course the rules state that in general you always round down.  Am I missing something? Is there a good explanation for why at first level you can't recover hitdice? "State-of-the-art" and "technology" Persistent live drive with a partition for persistence There are some web sites describing  new tools new features in [new versions of] old tools  that can create a persistent live drive from an iso file with Ubuntu 19.10 and the corresponding Ubuntu family flavours.  Why and how does it work? How is it different from earlier methods for persistent live drives? Isn't live the default for a cloned drive? Cardinality of the set of all real functions of real variable How does one compute the cardinality of the set of functions $f:\mathbb{R} \to \mathbb{R}$ (not necessarily continuous)? What is the name of an anime from 80s-90s movie/series in which there is a scene, maybe the end, where a girl (who has an​ armor) exchanges age with a dying man in a beach, so the man transforms into a baby and the girl grows to a woman? Is it possible to run Drush without root? I run a Linux server that is administered by a friend of mine, and at the moment I work with Filezilla.  I've heard that Drush is a trivial installation: it seems to require no configuration and work out of the box.   However, it looks for configuration in several places:     Drush installation directory,  the home directory (as .drushrc.php),    root directory of a Drupal installation, and  site directory of a   Drupal installation.  Since the configuration files are just PHP   scripts, they can  contain any PHP code that you would like to have   executed on startup of Drush.  one could for instance call ini_set()   to set the value of a PHP configuration option.   and the configuration file /opt/drush/drushrc.php with following content:    # Allow Drush to use 128 MB of memory. Use -1 for no limit. ini_set('memory_limit', '128M');   I see this is necessary because PHP's default is too low, but I'm not sure if I need higher-level privileges because of it.  Do I have to have root-level permissions on the server, or am I able to work with Drush without them?   Update:  As far as i understand this, i only have to ask my admin to get some more privileges (permissions)Note according to BetaRides answer i need to have more than only the access-data that the FileZilla needs - that are provided for the filezilla! Guess so - but i don not need root-permissions.  btw - i have secure-shell-access (ssh2 access) guess that this is enough -With that i can setup a sftp-connection to the server with filezilla just lemme know - if i can use the exactly same data for the shell access (with the command line tool=?!= What is an intuitive explanation for how PCA turns from a geometric problem (with distances) to a linear algebra problem (with eigenvectors)? I've read a lot about PCA, including various tutorials and questions (such as , , , and ).   The geometric problem that PCA is trying to optimize is clear to me: PCA tries to find the first principal component by minimizing the reconstruction (projection) error, which simultaneously maximizes the variance of the projected data.    When I first read that, I immediately thought of something like linear regression; maybe you can solve it using gradient descent if needed.  However, then my mind was blown when I read that the optimization problem is solved by using linear algebra and finding eigenvectors and eigenvalues. I simply do not understand how this use of linear algebra comes into play.  So my question is: How can PCA turn from a geometric optimization problem to a linear algebra problem? Can someone provide an intuitive explanation?  I am not looking for an answer like  that says "When you solve the mathematical problem of PCA, it ends up being equivalent to finding the eigenvalues and eigenvectors of the covariance matrix." Please explain why eigenvectors come out to be the principal components and why the eigenvalues come out to be variance of the data projected onto them  I am a software engineer and not a mathematician, by the way.  Note: the figure above was taken and modified from . delete vs delete[] operators in C++ Microsoft Excel mangles Diacritics in .csv files? Is it possible to get the ID of a Contact which is part of a Person Account?  I have a custom object which has a custom field referencing the Person Account, though it seems to be referencing the Contact directly. I have created a button which I am using to pass the ID into a Visualforce Page.  With the Insert Field drop-down on the create/edit button page I can put in {!Account.Id} or {!Contact.Id} but neither of these work. The Account ID is placed in the URL but is not the correct ID and the Contact ID is blank, which I assume is because the button is on a Person Account page and not a Contact Page. What is a "closed" or "duplicate" question? Questions can be closed or marked as duplicates.  What does it mean for a question to be &quot;closed&quot;? What does it mean for a question to be marked as a &quot;duplicate&quot;? Who can close a question? What are the reasons for closing a question ? Is closure the end of the road for a question? When are closed questions eligible for deletion?   Related        For more information, see &quot;&quot; in the . How can I trick Minecraft into thinking two computers are on the same wifi network? Minecraft's got an "Open to LAN" feature, which can be used to set up a local server when two computers running Minecraft are on the same network. Some young relatives of mine use this to play together whenever they're in the same house, but they'd like to be able to play together from their respective residences.  A server is not optimal because it's a bit complex. I've tried using Tunngle to spoof that the computers are on the same connection to no avail.  How can I convince Minecraft's "Open to LAN" that their two separate computers are on the same network? My colleague is using an application that consumes a lot of memory which makes the system too slow. Is it possible to share memory with other PCs over the Internet?   The system has 8 GB of RAM, and the application consumes more than 6 GB. What's an intuitive way to think about the determinant? In my linear algebra class, we just talked about determinants. So far I’ve been understanding the material okay, but now I’m very confused. I get that when the determinant is zero, the matrix doesn’t have an inverse. I can find the determinant of a $2\times 2$ matrix by the formula. Our teacher showed us how to compute the determinant of an $n \times n$ matrix by breaking it up into the determinants of smaller matrices. Apparently there is a way by summing over a bunch of permutations. But the notation is really hard for me and I don’t really know what’s going on with them anymore. Can someone help me figure out what a determinant is, intuitively, and how all those definitions of it are related? Spotlight with Halo applied is creating rings around light Here's a portion of a render I'm working on, which is backlit from behind by a spotlight with a "Halo" effect applied:    If you look carefully in the background, you'll notice the halo effect is creating "rings" of shadow as it fades.  How can I remove these rings and make the halo effect fade out smoothly?  I've played around with all the settings I can find without any success.  Here's my current settings for the spotlight: