Installing Ubuntu in a mac
What is different about the Mac ISO image?
A number of times I have asked a certain kind of ‘attractive nuisance’ question – that is, one in which I anticipate a certain kind of answer would be given that I already know I am going to find insufficient or entirely inadequate. Some examples:      A more abstract example would be asking ‘is it possible to do this 100% correctly’, where people itch to come up with hacks, workarounds and half-baked solutions of various degrees of robustness – while the point of the question is obtaining a fully correct and reliable solution.0 I try to be very explicit in the question body about what kinds of answers I am not interested in. And yet, every time I ask such a question, someone gives such an answer anyway, or an outright XY-type, i.e. frame-challenge answer – where in fact the framing of the question is exactly how I want it, and I don’t want it challenged. Since I have already said in the question body that such an answer would be inaqeduate, when I get one, I downvote it. I believe it’s only appropriate, but it tends not to be received very well – I get insulting comments and downvotes in retaliation. I realise that a proper answer would be much harder to come up with than an ‘obvious’ inadequate answer. I suspect that often a real answer should be negative: ‘there is no way to do that’ or ‘there is no way to answer that for sure’. Nevertheless, if that is the right answer, this is the one I want posted – I don’t want the Internet polluted with more tumbleweed of what is already well-known (and may even be subtly wrong), and I don’t want to give ‘A for effort’ upvotes. What is the most appropriate way to act in such a situation?  0 I am also reminded of when Gary Bernhardt  while trying to avoid reflexive ‘don’t use eval’ replies. Of course, expecting nuance from Twitter of all places is silly, but that’s beside the point. Contradiction between law of conservation of energy and law of conservation of momentum? Yesterday, while studying a simple question, a rather strange doubt hit my mind:     Consider a ball of mass $m$ moving with velocity $v$ that collides with a wall in a perfectly elastic collision and rebounds back with the same velocity. Taking the direction of initial motion of the ball as positive, the change in momentum of the ball is $-2mv$ and the wall is clearly at rest.   So, in order to obey the law of conservation of momentum, the wall must gain a momentum of $2mv$.  Now, this itself confused me a lot. I then applied the law of conservation of kinetic energy to this situation, and clearly the magnitudes of the initial and final velocities of the ball are equal, so kinetic energy of the ball is conserved and hence the final kinetic energy of the wall must be zero in order to conserve energy.  Now, this contradicts with the law of conservation of momentum, which says that the wall must gain momentum of $2mv$.  One more point: If we are talking about a wall then it is an important fact, which must be considered, that the wall is fixed on earth and so the mass of the wall is equivalent to that of earth, say $M$. If the law of conservation of momentum is applied now then we get velocity of the wall, say $V=2mv/M$ which is no doubt an extremely small value. But, the law of conservation of energy strictly says that the velocity of the wall must be exactly zero, not even the smallest value is allowed (theoretically speaking).   Please clarify this and correct me anywhere if I'm wrong. I have tried my best to make it clear what I want to ask :). Is there any difference between being ill and sick? Making a WinForms TextBox behave like your browser's address bar When a C# WinForms textbox receives focus, I want it to behave like your browser's address bar.  To see what I mean, click in your web browser's address bar. You'll notice the following behavior:    Clicking in the textbox should select all the text if the textbox wasn't previously focused. Mouse down and drag in the textbox should select only the text I've highlighted with the mouse. If the textbox is already focused, clicking does not select all text. Focusing the textbox programmatically or via keyboard tabbing should select all text.   I want to do exactly this in WinForms.  FASTEST GUN ALERT: please read the following before answering! Thanks guys. :-)     Calling .SelectAll() during   the .Enter or .GotFocus events won't   work because if the user clicked the   textbox, the caret will be placed   where he clicked, thus deselecting all   text.      Calling .SelectAll() during the .Click event won't work because the user won't be able to select any text with the mouse; the .SelectAll() call will keep overwriting the user's text selection.      Calling BeginInvoke((Action)textbox.SelectAll) on focus/enter event enter doesn't work because it breaks rule #2 above, it will keep overriding the user's selection on focus. Massive spam users and spam entries despite triple layer protection Are there any programs that will let me dictate (speech-to-text) to any program? Or at least to a text editor and text fields in Firefox.  I’m not interested in anything that uses an online service, it has to be on-device. It may be a commercial product. How to convert string to boolean php What is the function of the "Sticky edges" on/off setting in displays? I have installed Ubuntu 12.04 (Precise Pangolin). If I open System Settings &gt;&gt; Displays there is a new (?) on/off button for a setting named Sticky edges.  Can someone tell me what this setting is supposed to control? Ruby Style: How to check whether a nested hash element exists Intuitive Understanding About the Implicit Function Theorem In multivariable calculus, given a function like $F(x,y,z) =0$, the implicit function $z=f(x,y)$ exists if and only if $\frac{\partial F}{\partial z} \not = 0$. And the implicit function is given by $\frac{dz}{dy}=-\frac{\frac{\partial F}{\partial y}}{\frac{\partial F}{\partial z}}$.   The theorem can be proved by mathematical reasoning. But I want to know whether there is some intuitive understanding of the theorem, say geometry intuition in the three dimensional space, etc. I moved a database from SQL Server 2005 to SQL Server 2012. Is there any way of restoring all the logins on the new server? Changes to "close as duplicate" (part deux) Ubuntu does not offers me "install alongside Windows" Any of the partitions makes in Windows was not recognised by Ubuntu, or Zorin OS, or LinuxMint. It's like a blank hard disc, 250 gb free. I'm a new Linux user, but what confuses me is that I was able to install Ubuntu alongside Windows on my laptop with no problems, but on PC... no way! Are "white" and "black" ever capitalized when referring to people? extending convergence radius using one boundary point Show that if $f(z)=\sum\limits_{n\geq0}a_nz^n$ is analytic in $\{z\in\mathbb{C}:|z|&lt;1\}\cup\{1\}$ and $\forall n\geq0:a_n\geq0$ then the radius of convergence of the power series is strictly larger than $1$.  My approach:   Let $D=\{z\in\mathbb{C}:|z|\leq1\}$.  We have that $f(1)$ converges, so $\sum\limits_{n\geq 0} a_n&lt;\infty$. Moreover since the $a_n$'s are all positive we have that $|a_n|=a_n$, therefore $\sum\limits_{n\geq 0} |a_n|=\sum\limits_{n\geq 0} a_n&lt;\infty$.  Let $f_n(z)=a_nz^n$, then $\forall z\in D, n\geq 0$ we have:  $$|f_n(z)|=|a_nz^n|=|a_n|\cdot|z^n|=a_n\cdot |z|^n\leq a_n\cdot 1^n\leq a_n$$  Then, applying Weierstrass M-test we get that the power series is convergent in $D$.  Now, I need to "find" an open ball $B$ such that $D\subset B$ and the power series is convergent in it.  Edit  $f$ is analytic in $1$, so there is an open set $U$ that contains $1$ such that   $$f(z)=\sum\limits_{n\geq 0} b_n(z-1)^n$$  Does it mean that the series is convergent in $U$?   I can see that we have that the two series coincide in $D\cap U$. Why didn't the Ministry use Veritaserum to question criminals? The truth potion (Veritaserum) is one of the most powerful potions that forces the drinker to speak truth. Then why didn't Ministry used it in any criminal cases instead of long discussions and proceedings? I know there are antidotes to the potion (Dumbledore tells Harry in the 6th book , "Slughorn might have been carrying antidote to veritaserum ever since I asked him about the memory"), but why don't keep criminals in custody until the effect of the antidote wears out and then make them drink veritaserum. Won't that result in perfect judgement? Proof: Every convergent sequence of real numbers is bounded Could someone give an example of a ‘very’ discontinuous derivative? I myself can only come up with examples where the derivative is discontinuous at only one point. I am assuming the function is real-valued and defined on a bounded interval. How to call a confirmation dialog box? I have a button in my menu named "New File" as shown:    and I want when I click on the "New File" button to imitate what the Blender File->New does, where a check message box appear first confirming that you want to reload the Start-up File and if pressed then the startup file is loaded as shown below.    This is my script, when I press on new it opens the startup file without checking:  class NewFile(bpy.types.Operator):     """New File"""     bl_idname = "wm.newfile"       bl_label = "New File"     bl_options = {'REGISTER', 'UNDO'}      def execute(self, context):         bpy.ops.wm.read_homefile()         return {"FINISHED"} I tried the first experiment in chapter 5 in the Metafontbook: ran mf, typed \relax and drawdot (35,70); showit;.  This opened a window entitled Metafont, but containing nothing.  What's missing?  Using TeXlive 2020 on Linux. PS. After adding drawdot (65,70); showit; I see both dots. PS II. Which have now disappeared, after I changed window-manager workspace and back. PS III.  Typing showit; before the first drawdot opens a window and allows the first dot to be seen, but after having switched workspaces and back, I haven't found any way of bringing the picture back, short of drawing something more and showing it.