No java command after installing JDK
How to setup Java-Home and Path in Ubuntu 12.04
What do the colors mean in htop? How to copy file path to clipboard? Is there a way to copy the currently selected filename, including the path, to the clipboard? Ideally this would be through the right-click menu.  Some degree of flexibility would be useful, like the ability to copy just the filename, path+filename, filename minus extension, etc. This isn't essential, though, as long as it can copy the path+filename.  The solution must be compatible with Windows XP, Windows Vista and Windows 7. SVM for unbalanced data I want to attempt to use Support Vector Machines (SVMs) on my dataset. Before I attempt the problem though, I was warned that SVMs dont perform well on extremely unbalanced data. In my case, I can have as much as 95-98% 0's and 2-5% 1's.   I tried to find resources which talked about using SVMs on sparse/unbalanced data, but all I could find was 'sparseSVMs' (which use a small amount of support vectors).  I was hoping someone could briefly explain:   How well SVM would be expected to do with such a dataset   Which, if any, modifications must be done to the SVM algorithm What resources/papers discuss this What programming languages can I use in Blender? What version of Python does Blender use and are other languages available? Also, does Python work the same in Blender as when you write console applications or when working with Pygame or are there any differences? If so, what are the main differences? Is there implementation of tri-planar mapping in Cycles renderer? Is it possible to have tri-planar mapping in cycles?  Like in corona renderer or fstorm? Why is a person's location exclusively tied to their communicator? In Star Trek it is frequently seen that when a crew member wants to avoid being tracked, they'll leave their communicator somewhere (quarters, corridor etc) which throws the computer and ship's security off their trail.  However, the entire interior of the ship is under constant surveillance by the internal sensors. Barring damage to the ship or sensors, or some space phenomenon causing radiation X to create interference, why aren't these internal sensors able to continue tracking every person on board regardless of where their comm-badge is? In the worst case, they should be able deduce who the errant individual is by simple subtraction: "I can see where all the other comm-badges are, so subtract them and the remaining life form must be the person I am looking for." But this never seems to be done either.  Is Star Fleet security really so inept or is there some other limitation in play that is never mentioned? how to hide files from package explorer How do I get the feature id after featureAdded signal (PyQGIS)? I'm trying to make an edit form in QGIS (Python code) ,and i want after feature drawing to get the id, and the feature to be selected. Do you have any ideas to do that?  Tried so far:  self.iface.activeLayer().featureAdded.connect(self.myfonction)  def myfonction(self):      for feat in self.iface.activeLayer().getFeatures():         self.iface.activeLayer().setSelectedFeatures([feat.id()]) I am trying to identify a sci-fi movie from the 80's or 90's, with the following parameters:  Setting:    Scenes of a red desert planet   Culture:    Either people roam fairly solo and try to acquire resources to survive, or you live in a weird society where if a stranger is captured he needs to play in a game of fight to the death.  Mobility:      One foil character has a giant battle-bot-looking tank as his form of transportation through the desert. Protagonist has a car that has a plastic half bubble on top to look out from.   Robot:      The protagonist runs around in the beginning of the film with a female robot/android whose face is melted off after it has acid touch its face.(This scene happens next to the protagonist's rover)  Love interest:      Somehow protagonist comes across female protagonist in desert. She smells really bad and is hungry. They sleep outside, and he tells her to sleep away from him. He uses a thermal blanket(the first I ever saw in my life). She wakes up next to him, smelling horrible. He bathes her in some water hole they find(as if water were not scarce and they could just waste water.)   Pupa monsters:      Scene where they are in a building and they are trying to get out. They come across a room that is white, in which multiple giant, white, snot, pupa are hanging securely from the ceiling. Through curiosity, they disturb them, and now they have to get out of that room fast.  Boss Antagonist:      Pervert bionic man, that is actually attached to a giant robotic arm, as only form of movement. He is in black and has a pale bald head as his most human looking part. Taylor expansion for $\arcsin^2{x}$ I stumbled upon this particular expansion that was included in  post.    $$ \displaystyle \arcsin^{2}(x) = \frac{1}{2} \sum_{n=1}^{\infty} \frac{1}{n^{2} \binom{2n}{n}} (2x)^{2n}$$    This caught my eye because I remember trying to derive a Taylor series for $\arcsin^{2}(x)$ a while ago without much success.  Can anyone prove this or point me to a material that would show a proof of this identity?  EDIT :  Feel free to use any mathematical apparatus at hand. I'm not interested in a proof fit for a certain level, nor am I looking for utmost elegance (though that would be lovely). Do I have to worry about copyright issues for code posted on Stack Overflow? I was wondering about the copyright of code snippets from answers. Let's say you ask a question and the solution consists of ten lines of code, which are given in an answer. Are there any restrictions about the use of that code?   It seems that the content of this page is under the . So does one have to attribute the author if code is used in an open source project? Can it be legally used in closed source projects at all?  I guess ten lines of code are not really problematic, but is there a critical number of lines? Tighten rope without turnbuckles? I have two 4-ft x 4" x 4" wood posts, and each post has a screw eye. There's 12 feet of distance between each post.  How can I tighten a piece of 1/2" diameter rope that goes through each screw eye and it's stretched tightly without having to buy turnbuckles?  There has to be a knot just for this. Are the foods in the Star Wars Universe the same as ours'? Do they have strawberries or potatoes or something? I know that they might have some food other than the food that we also have, but I'm wondering if they have any food like ours'. My (very simple) question to a friend was how do I prove the following using basic trig principles:  $\tan75^\circ = 2 + \sqrt{3}$  He gave this proof (via a text message!)  $1. \tan75^\circ$   $2. = \tan(60^\circ + (30/2)^\circ)$  $3. = (\tan60^\circ + \tan(30/2)^\circ) / (1 - \tan60^\circ \tan(30/2)^\circ) $  $4. \tan (30/2)^\circ = \dfrac{(1 - \cos30^\circ)}{ \sin30^\circ}$    Can this be explained more succinctly as I'm new to trigonometry and a little lost after (2.) ?    EDIT  Using the answers given I'm almost there:   $\tan75^\circ$    $\tan(45^\circ + 30^\circ)$   $\sin(45^\circ + 30^\circ) / \cos(45^\circ + 30^\circ)$   $(\sin30^\circ.\cos45^\circ + \sin45^\circ.\cos30^\circ) / (\cos30^\circ.\cos45^\circ - \sin45^\circ.\sin30^\circ)$    $\dfrac{(1/2\sqrt{2}) + (3/2\sqrt{2})}{(3/2\sqrt{2}) - (1/2\sqrt{2})}$   $\dfrac{(1 + \sqrt{3})}{(\sqrt{3}) - 1}$   multiply throughout by $(\sqrt{3}) + 1)$   Another alternative approach:   $\tan75^\circ$    $\tan(45^\circ + 30^\circ)$   $\dfrac{\tan45^\circ + \tan30^\circ}{1-\tan45^\circ.\tan30^\circ}$   $\dfrac{1 + 1/\sqrt{3}}{1-1/\sqrt{3}}$   at point 6 in above alternative How to run xrandr commands at startup in Ubuntu I don't understand why su - is preferred over su to login as root. How to pass parameters to function in a bash script? I'd like to write a function that I can call from a script with many different variables. For some reasons I'm having a lot of trouble doing this. Examples I've read always just use a global variable but that wouldn't make my code much more readable as far as I can see.  Intended usage example:  #!/bin/bash #myscript.sh var1=$1 var2=$2 var3=$3 var4=$4  add(){ result=$para1 + $para2 }  add $var1 $var2 add $var3 $var4 # end of the script  ./myscript.sh 1 2 3 4   I tried using $1 and such in the function, but then it just takes the global one the whole script was called from. Basically what I'm looking for is something like $1, $2 and so on but in the local context of a function. Like you know, functions work in any proper language. What are the requirements to get the "Weed Eater" hat? The hat's description says     answer a question qualifying for the Tumbleweed badge that gets accepted   During the winter bash, I  a question that is a , and it got accepted; yet I did not get the hat. However  answer  and did get the hat. (What was the difference?)  So what are the exact requirements to get the  hat? Normal ubuntu desktop will update ubuntu-desktop package and it's dependencies on release upgrade. Will Ubuntu minimal cd install ubuntu-desktop on release upgrade or just installed packages? regular expressions / pattern matching on ubuntu command line