Windows and Ubuntu
How do I remove Windows 7 from my dual boot system with Ubuntu?
What's the difference between an argument and a parameter? When verbally talking about methods, I'm never sure whether to use the word argument or parameter or something else. Either way the other people know what I mean, but what's correct, and what's the history of the terms?  I'm a C# programmer, but I also wonder whether people use different terms in different languages.  For the record I'm self-taught without a background in Computer Science. (Please don't tell me to read  because I'm asking this for the benefit of other people who don't already have a copy of 's marvellous book.)  Summary  The general consensus seems to be that it's OK to use these terms interchangeably in a team environment. Except perhaps when you're defining the precise terminology; then you can also use "formal argument/parameter" and "actual argument/parameter" to disambiguate. Who was/were the first Jedi? Can there be multiple paths for which Fermat's least time principle can be obeyed? Can there be more than one path for which Fermat's least time principle is obeyed? I want to extrude a curve in two directions.    Or join both curves into one, is it possible? I've tried copying it and then join segments, but I don't see Remove Doubles option while working with curves. How does a transformer transmit power from the primary to the secondary? I'm trying to get my head wrapped around transformer operation and in the process regretting the times I snoozed in my Electromagnetics class as a EE student back when I was a lad :)  I'm looking for an intuitive understanding, but not just an analogous one. I'd like it to be grounded in the actual physics of what's happening. I've found several excellent sources on the web, but they all seem to skirt this question.  I've come across a few interesting hints and am now tantalizingly close, I think, but still yearning :)  Fact 1: Although varying sinusoidally, the "peak-to-peak" flux, so to speak, in a transformer's core is essentially constant (for a given voltage applied to the primary), regardless of the load.  My intuitive hypothesis was that variation in the "strength" of the flux was what transferred the energy from the primary to the secondary, but this fact would seem to contradict that theory. I had thought that the primary makes a bunch of flux based on the current flowing through it and the secondary sucks it up to make current of its own. No dice, it seems.  Then of course there's the fact that the formula for flux involves only voltage, time (frequency), and turns :)  Fact 2: The current in the primary is (approximately) 90 degrees out of phase with the voltage at no load, and approximately aligned in phase at full load.  This fact seems very promising and also curiously satisfying. It would imply that the Volt-Amps (VA) of the primary is constant and only the power factor changes as the current load on the secondary increases.  But I still don't get how the energy is actually being transferred. It seems vaguely like the flux is just there as an energy conductor or something and some other phenomenon is actually doing the energy transfer bit.  Can someone see what I'm missing and explain what's actually happening in there? I have a matrix and need to highlight some elements in the matrix. I have found how to highlight a single element (I want to put the cell in the square):  $$ A = \begin{bmatrix} \fbox{0} &amp; \fbox{0} &amp; 0 \\  \fbox{0} &amp; \fbox{0} &amp; 0 \\ 1 &amp; 1 &amp; 1 \\  \end{bmatrix}$$   But how can I outline elements of the submatrix like in the picture below? I need just a frame where some elements are located. I have two feature Datasets. Both are Polygons. Dataset A has very big Areas and Dataset B just small ones. Now, B still overlaps in 2 or 3 Zones from Dataset A.   I want to perform a spatial join and put the result comma seperated in just one row like this:  Zone_ID_A  |  Zone_ID_B     1       |   2,3    2       |   2,4    3       |   5    4       |   1,6   I know this is possible with ArcMap but i could not figure out a way to do this in QGIS, any ideas? How does Dijkstra's Algorithm and A-Star compare? linebreak in description title Example of $f,g: [0,1]\to[0,1]$ and Riemann-integrable, but $g\circ f$ is not? Moderncv adding date of birth to personal information to set start Thunderbird in minimized mode at startup, but it wasn't helpful.   After following the instructions, I could not even start Thunderbird. So I was forced to start TB in safe mode to delete the "FireTray Plugin" and fix this issue. After that it started to work but it deleted all my email accounts and I had to do that chore all over again .  So is there any working way to start Thunderbird minimized on start-up? Does the existence (now proved) of gravitational waves imply the existence of Gravitons? I studied the theoretical part about the Gravitational waves in General Relativity (linearization of gravity and small perturbations of the metric and so on).  But I was wondering about: since electromagnetic radiation is composed/carried by Photons (or better:the EM force), shall gravitational waves be composed/carried by Gravitons?   In the end:do gravitational waves imply the existence of gravitons? Or it's something unrelated and off topic? Find the maximum value of $ f(x) = \int^{x}_{0} \sqrt{(x^2-x)^2+y^4}~dy$ a) Determine the number of ways to colour a 1 by n grid using the colours red and white if an even number of squares are to be coloured red.   Note that n is greater than or equal to 1 and the number of red squares could be 0.  I know I must consider the cases of n being even and odd, and determine the sum, from zero to n of the squares being red, where the number of red squares is even. But I just want to make sure I haven’t missed any arrangements by saying a) is $2^{n-1}$ when n is even and $2^{n-1}-1$ when n is odd.  b) Determine the number of ways to colour the squares using red, white and blue if an even number of squares are to be coloured red.  For this case, I can have arrangements including red only, white only, blue only, white and blue only, red and white only, red and blue only, and finally all three colours.  Thank you for any help provided. There are two checkboxes for Run As Administrator in the Properties dialog for a shortcut in Windows 7. One is under the Shortcut tab in the Advanced Properties dialog, and the other is under the Compatibility tab.  I've seen this under Windows 7 and Windows Server 2008. It might be in Vista and other versions, but I'm not sure.  What is the difference between these two settings? iPad 1 update from 5.1.1 to 7.1 How can I update iPad 1 from iOS 5.1.1 to iOS 7.1?  I tried checking for updates but I get a message "your software is up to date". List of interesting math videos / documentaries This is an offshoot of the question on . I have listed a few videos/documentaries I have seen. I would appreciate if people could add on to this list.  $1.$ Story of maths      $2.$ Dangerous Knowledge    $3.$   $4.$   $5.$ Controversy over verb choice in "neither you nor I {is/am/are} in control" PDF upload silently fails I dunno since when, but upload of PDF images fails, this hurts especially on tex.SE.  Could this be an effect of an updated /etc/ImageMagick-6/policy.xml on the imgur server?  At least on my Ubuntu 18.04 LTS machine, this file was modified two weeks ago.