ifconfig does not recognize eth0, only wlan0 and lo (Ubuntu 14.04, Macbrook Pro)
network manager says "device not managed"
According to :     By looking for trades that take place in between the bid and ask, you   can tell when a strong trend is about to come to an end. This is   because these trades are often placed by large traders who take a   small loss in order to make sure that they get out of the stock in   time.   A trader when buying needs to buy at the ask price and when selling needs to sell at the bid price. So how can a trade happen 'in between' the bid and ask? Show $\,p\mid 9^q -1 \implies q\mid p-1$ for odd primes $p$ and $q$ If $p$ and $q$ are odd primes show that $$p|(9^q -1) \implies q|(p-1).$$ ....  I am having difficulty to prove this.  Yes that was the question I have misunderstood between 9 and q!!! Attributing contributions to academic work that occur in Stack Exchange Sometimes we may ask questions on stack exchange or online forums wherein the response is helpful or even essential to a piece of work that gets published in an academic journal. If this occurs, how should credit be given to those involved in the exchange? Should they all be included as authors? Should a link to the forum be included as a reference in the paper?  Once something is in a stack exchange or forum, it's "published". Perhaps in the future, the current peer review model will transform into people writing blogs and posting in forums and databases. But for now, how might this issue be dealt with while forums, blogs, etc coexist with journals? Should a gas water heater be shut down if the water main has to be turned off? I have a brand new AO Smith 50gal gas water heater. Today there was a burst pipe from the cold spell we're having currently, so I had to turn off the water main to the house until the plumbers get here tomorrow.  With that, nobody had used any hot water all day so it should be full, but do I need to turn the water heater off until the water can be turned back on tomorrow to avoid any damage etc? How to revert an update? The latest xorg update was a big regression for me on a dual display setup. Is there a simple way to revert to the previous version?  I'm on Lucid Lynx. Replacing strings in files based on certain search criteria is a very common task. How can I    replace string foo with bar in all files in the current directory? do the same recursively for sub directories? replace only if the file name matches another string? replace only if the string is found in a certain context? replace if the string is on a certain line number? replace multiple strings with the same replacement replace multiple strings with different replacements Check and fix SD card errors within Android itself? how much space does a given package, and dependencies, cost? Run true multiple process instances of gnome-terminal I would like to know if there is some way to share a variable or an object between two or more Servlets, I mean some "standard" way. I suppose that this is not a good practice but is a easier way to build a prototype.  I don't know if it depends on the technologies used, but I'll use Tomcat 5.5    I want to share a Vector of objects of a simple class (just public attributes, strings, ints, etc). My intention is to have a static data like in a DB, obviously it will be lost when the Tomcat is stopped. (it's just for Testing) Graphics file extensions and their order of inclusion when not specified When using 's \includegraphics you can specify the file extension or not. For generic use and perhaps portability, extensions are commonly dropped. The types of "approved" inclusions and their order of precedence depends on the driver/compiler being used. What are these driver-defaults?  Related: Is it feasible to convert math in a picture, say written by hand, into LaTeX?   For example, I'd deem it faster to write down (de novo)  a 10 x 10 matrix with long, complex entries, rather than typing it in LaTeX or MathType. If I then take a picture or scan my writing, how can it be rendered or transformed into LaTeX? If column matches another file, print every line with match (awk/grep) I have an older iPod touch which which supports up to iOS 6.1.6 and nothing newer.  This device is equipped with a Linea Pro barcode scanner and previously had an application called "" installed.  Recently I was attempting to do some work on a web application I wrote and realized that I needed to update to a newer version of Web Barcode - but unfortunately the Apple ID saved on my device was deactivated a few years ago.  So I went to settings and updated it with my current Apple ID.  Then again tried to update the App from the Apple store.  Still no dice - it was asking me for the password on the old account.  So then I figured I'd just remove it and reinstall from scratch.  Deleted the app and went to the store but now I am met with a message that the new version requires at least iOS 8.0.  I feel I followed a very logical series of steps to update this application and while I can understand that I won't be able to install the newest version, how can I get the old version back?  The device is completely useless without the barcode scanning application and the Apple store is now refusing to install any version at all on my device.  What can I do to get the original version of this application reinstalled? Firefox doesn't launch in Ubuntu 13.04 Firefox starts when I use sudo in the terminal, but not from the launcher. All the other apps work like a charm, just not Firefox. How can I fix this? Why is 24.0000 not equal to 24.0000 in MATLAB? I am writing a program where I need to delete duplicate points stored in a matrix. The problem is that when it comes to check whether those points are in the matrix, MATLAB can't recognize them in the matrix although they exist.  In the following code, intersections function gets the intersection points:  [points(:,1), points(:,2)] = intersections(...     obj.modifiedVGVertices(1,:), obj.modifiedVGVertices(2,:), ...     [vertex1(1) vertex2(1)], [vertex1(2) vertex2(2)]);   The result:  &gt;&gt; points points =    12.0000   15.0000    33.0000   24.0000    33.0000   24.0000  &gt;&gt; vertex1 vertex1 =     12     15  &gt;&gt; vertex2     vertex2 =     33     24   Two points (vertex1 and vertex2) should be eliminated from the result. It should be done by the below commands:  points = points((points(:,1) ~= vertex1(1)) | (points(:,2) ~= vertex1(2)), :); points = points((points(:,1) ~= vertex2(1)) | (points(:,2) ~= vertex2(2)), :);   After doing that, we have this unexpected outcome:  &gt;&gt; points points =    33.0000   24.0000   The outcome should be an empty matrix. As you can see, the first (or second?) pair of [33.0000 24.0000] has been eliminated, but not the second one.  Then I checked these two expressions:  &gt;&gt; points(1) ~= vertex2(1) ans =      0 &gt;&gt; points(2) ~= vertex2(2) ans =      1   % &lt;-- It means 24.0000 is not equal to 24.0000?   What is the problem?    More surprisingly, I made a new script that has only these commands:  points = [12.0000   15.0000           33.0000   24.0000           33.0000   24.0000];  vertex1 = [12 ;  15]; vertex2 = [33 ;  24];  points = points((points(:,1) ~= vertex1(1)) | (points(:,2) ~= vertex1(2)), :); points = points((points(:,1) ~= vertex2(1)) | (points(:,2) ~= vertex2(2)), :);   The result as expected:  &gt;&gt; points points =      Empty matrix: 0-by-2 Do I need to upgrade RAM from 4GB to 8GB for Android development? I'm an android developer and have laptop with 4GB RAM. When I compile my project the RAM is used at 100%.    If I add more RAM will it solve the problem? Activating 'missing' standard GRASS utilities in QGIS Processing toolbox A word to describe "work that is ready to be done" Who can use magic scrolls? I'm confused about who can use scrolls in 5e. In the DMG, p139 under Magic Item Categories: Scrolls, it states that:     Any creature that can understand a written language can read the   arcane script on a scroll and attempt to activate it.   This implies that anyone can try to cast a spell using a scroll. However, on p.200 in the Spell Scroll entry it states that:     If the spell is on your class's spell list, you can use an action to read the scroll and cast its spell without having to provide any of the spell's components. Otherwise, the scroll is unintelligible.   Then there is the bit about a DC 10 + scroll spell level ability check if the spell is higher than a spell slot that you can cast.     If the spell is on your class's spell list but of a higher level than you can normally cast, you must make an ability check using your spellcasting ability to determine whether you cast it successfully. The DC equals 10 + spell's level. On a failed check, the spell disappears from the scroll with no other effect.    So, which is it? Can anyone who can read a language use a scroll (like a fighter) if they make an arcana check, or just a PC with that specific spell in their spell list (only spell casters)?