How can I use a Linksys AC 1200 Wireless Adapter?
AC1200 Wireless adapter in Ubuntu 19.10
Why does change in speed of a wave make it refract? When a light wave enters a medium with a higher refractive index (e.g. from air to standard glass) and its speed decreases, why does that make it refract/bend?  I understand that wavelength decreases and frequency stays the same and therefore its speed decreases, but I can't find anywhere whatsoever why the speed decrease cause the wave to refract. So could someone please explain this? Is there a subtle difference between "somebody" and "someone", "anybody" and "anyone"? Is there a way I can share the 3.42 GB download of Windows 8.1 from Windows Store? Windows 8.1 is out, and I would like to know if it is possible to share the Windows 8.1 download upgrade between different computers so that I don't have to download it over and over again?  This might be helpful for people who are on a metered connection. Store is downloading 3.42&nbsp;GB of data so it must be stored somewhere. Is there a way I can copy it to my other computers and start the setup so that I don't have to download it over and over again on each computer I own? Is Ubuntu based on Debian unstable or Debian testing? which of the two it is? I am trying to understand the sentence  the mean minimizes the mean squared error.   from wikipedia .  From a previous post  I can see a formal proof which according to the authors prove that the mean minimaze. But my objection on that prove is that is you substitute m with median all the reasoning still stands.  Therefore, I restricted myself to one dimension and built the following example :   MSE = 1/n[SUM(Y_hat_i - Y_i)**2]   Given the following distribution Y = [5,3,2,7,4], minimizing MSE I intended as in the following: I should find a function Y_hat such that when it is applied to the MSE formula (more specifically to each element of the Y distribution), we are sure that we obtain the minimum value. For simplicity, I could consider the Y_hat as any measure or function for the central tendency, including, mean, median, mode, etc.  Lets suppose, Y_hat = mean (=4.2 for our distribution), therefore, I did all the calculations such as:  1/5 [(4.2-5)**2 + (4.2-3)**2+ (4.2-2)**2 + (4.2-7)**2  + (4.2-4)**2 ] = 2.96   Let's suppose, Y_hat = median (=4 for our distribution), therefore, I did all the calculations such as:  1/5 [(4-5)**2 + (4-3)**2+ (4-2)**2 + (4-7)**2  + (4-4)**2 ] = 2.8   If I did all the calculation correctly, the result shows that for this case, the median is minimizing better than the mean.  I am sure, I am doing something wrong and missing important aspects of the overall reasoning.  Please, could you provide any clarification on the above topic? I would really appreciate it.  Many Thanks in advance, Best Regards, Carlo What are the difference between:    the action $\int_{t_{1}}^{t_{2}}(L+H) dt$ that we use in the principle of least action, and  the action integral $\int_{t_{1}}^{t_{2}}L dt$ that we use in Hamilton's variational principle?   References:   H. Goldstein, Classical Mechanics, Section 8.6. H. Goldstein, Classical Mechanics, Chapter 2. What does it mean to say "a divides b" I am not a number theorist and I am learning about relations.  I encountered a relation that says      $a \leq b$ if $a$ divides $b$   Can someone clarify what it means to a number to divide another number?  Does it mean what I think? $a$ divides $b$ if $a | b \in \mathbb{Z}$?     So given a set $S = \{a, a^2, a^3, \ldots\}$, with relation $a | b \leftrightarrow a \leq b$, does the relation hold   going from left to right or right to left? i.e. $a|a^2, a^2|a^3, \ldots$ How do I transfer my Pokemon Go account to another device (Android to Android)? I was having trouble playing the game on my android so I downloaded it to my wife's phone (Galaxy S6). I read some posts on how to get it running on my android and it worked but, my level 7 account is on my wife's phone.  How do I get it back to my android? When I sign out and back in it doesn't ask for any sign in info. I've tried deleting the app's data and even uninstalling and re-installing, but it still doesn't ask for sign-in info. I wanted to know which php version I am using so I wrote the standard script:   phpinfo();   Which gives me  PHP version 5.6.10   The correct PHP version needed for my application. When I tried in terminal:  php -i   or  php -v   It shows me:  PHP version 5.3.2   Which I don’t need. Then I tried with:  which php   It shows me:  /usr/bin/php   Now I am confused which version of PHP I am using. The files are uploaded to the hosting website and I cannot make any changes to the config files like httpd.conf or php.ini. Basically, I'm trying to override some files of the Uncode theme. But this is not a theme-specific question: it can be applied to any theme. The Uncode theme has a custom dir 'partials' (/uncode/partials/) that contains some layout elements. On my child theme I created a 'partials' folder as well (my-child-theme/partials), but the inner files seem not to be overridden. Is it normal? WP docs say that any file of the same name should be overridable, but is seems that's not true. Am I doing something wrong? recovering deleted file held open by apache? Suppose an apache log file gets deleted but it's held open by apache; then this is what I am doing:  pid=$(lsof | grep text.txt | awk '/deleted/ {print $2}') fd=$(lsof | grep text.txt | awk '/deleted/ {print $4}' | grep -oE "[[:digit:]]{1,}")  cp /proc/$pid/fd/$fd directorytobecopied/testfile.txt   This is what I am doing to recover the file and put it back where it was. Is there any simpler way of doing this because above code doesn't look good. Furthermore how do I know from where the file was deleted(directorytobecopied) so that I don't have to manually ask somebody where the file was located originialy and put it back there. How to change account profile picture? I can't believe I have to ask this...but, how do I change my account profile picture in Ubuntu 12.04 Desktop? One would think it would be under the "User Accounts" section. Is there anything that is totally random? When I say totally random, I mean absolutely random, not pseudorandom. If I want to say "totally random" numbers such as 1,26,17,4,1 and 27, although I see them to be totally random, they aren't. These are numbers that I think are influenced by my childhood, ideology and everything that I've seen. So, what do you think? Is there anything completely random? Ubuntu 14.04: very slow UI in Oracle VirtualBox Short summary: 14.04 is much slower than 12.04 even with more RAM assigned.  I'm using latest VirtualBox 4.3.10 on Mavericks 10.9.2. How can I make it faster? in my mariadb i have replication, i tried to change the location of the binlogs by changing the configuration file as so: log-bin = /new/path/mysql-bin I also tried to change the index location as so: log_bin_index = /new/path/mysql-bin.index but every time when I restart I see that the location of the binlog files is /var/lib/mysql... i tried to check with mysqld --verbos --help | grep bin and I saw that the lob-bin parameter is mysql-bin and not what I wrote in the cnf... how to I make the MySQL to take the value of the log-bin from the cnf file? this is the cnf file of the MySQL for sure... "dev/sda1: clean, ..." This message appears after I startup my laptop, then it won't continue booting An awful lot of people seem to use the phrase "substitute X for Y" to mean "replace X with Y", while I've always used and understood it as "replace Y with X". This makes sense to me, given that a substitute is the replacement, not the thing which has been replaced.  I thought I might be able to figure things out from a dictionary, but now after seeing two sorts of definitions, I'm even more confused:   to put or use in the place of another to take the place of; replace   The first one suggests that the object will be the substitute (replacement), the thing put into place, while the second suggests that the object will be the thing which has been replaced.  Is one of these usages more correct in any sense? (I know this is probably a pointless question, since people will continue to speak the way they speak.) Is there perhaps a difference between American and British English?   And most importantly, is there any reliable way to tell what someone means when they ask how to substitute honey for sugar, or is the verb simply guaranteed to cause confusion? C# 3.0 Auto-Properties - Is it possible to add custom behaviour? I would like to know if there is any way to add custom behaviour to the auto property get/set methods.  An obvious case I can think of is wanting every set property method to call on any PropertyChanged event handlers as part of a System.ComponentModel.INotifyPropertyChanged implementation.  This would allow a class to have numerous properties that can be observed, where each property is defined using auto property syntax.  Basically I'm wondering if there is anything similar to either a get/set template or post get/set hook with class scope.  (I know the same end functionality can easily be achieved in slightly more verbose ways - I just hate duplication of a pattern) What is the purpose of a Windows Workgroup? In Microsoft Windows, what is the purpose of a Workgroup? I understand that a Domain allows the administration of security (user names, passwords, file access, etc.) to be centralized. But what does a Workgroup give you? I've downloaded ubuntu-12.04.1-desktop-amd64.iso via Chrome. Once that was done, I wanted to burn it onto a CD but I can't find the .iso file.   When I opened the Downloads folder, the .iso extension is not there anymore, and it opens with WinRAR for unzipping. I tried unzipping and searching for any ISO files but no luck.   I'm trying to add Ubuntu onto VirtualBox on Windows 7 host OS. Please help.