Ubuntu 20.4 DVD and USB copies are not recognised by Mac boot manager.. Neither show up.. Unable to install to MacBook with OS X 10.7 Lion installed..
If you select "USB" and "Mac" on , it gives a series of command line instructions to make a USB key which the MacBook will boot into Ubuntu from.  I've followed them to the letter two or three times on different USB keys, and it doesn't work. There's a very great deal of technical discussion about EFI etc. but this set of instructions seems to suggest it should just work, but it doesn't.  Help? I'm increasingly unhappy with the more locked-down approach Apple is taking, and I'd quite like to start using Linux with a view to transitioning over to using it as my main operating system, but booting from the CD takes forever, runs slowly and I'm really hoping to get it moving off USB.  Can anybody help me?
Is a continuous function $ f\colon(0,\infty)\to R$, such that $f(x)\leq f(nx)$ increasing? Linear mixed effect model vs. Ordered Probit vs. Ordered Logit with ordinal response I have a set of data with an ordinal response ranging from 1-5 (worst to best) and a categorical predictor with five unordered levels. The experiment is a language experiment whereby subjects are asked to rate different sentence types. In the literature it seems that people fit lmer() most of the time by scaling the ordinal response per subject (i.e. taking the mean response and standard deviation of that subject and dividing the every single response by it.). On the other hand, it seems a reasonable approach to use ordered linear mixed effects probit models or ordered linear mixed effects logit models as implemented in e.g. MCMCglmm() or clmm().  (1) I find myself asking what the best method would be. When is one method to be prefered over the other in an experiment as I have sketched above?  (2) Why do people prefer fitting an lmer() model with a scaled response? What is the advantage?  (3) If it is advisable to use an ordered probit or logit model, how do I decide between an ordered probit or ordered logit model?  Thanks for any help! Redirect 301 with hash part (anchor) # The Newtonian description of gravity can be formulated in terms of a potential function $\phi$ whose partial derivatives give the acceleration:  $$\frac{d^2\vec{x}}{dt^2}=\vec{g}=-\vec{\nabla}\phi(x)=\left(\frac{\partial\phi}{\partial x}\hat{x}+\frac{\partial\phi}{\partial y}\hat{y}+\frac{\partial\phi}{\partial z}\hat{z}\right)$$  However, in general relativity, we describe gravity by means of the metric. This description is radically different from the Newtonian one, and I don't see how we can recover the latter from the former. Could someone explain how we can obtain the Newtonian potential from general relativity, starting from the metric $g_{\mu\nu}$? How to find out why "context is incorrect"? I have a file: Base.h  class Base; class DerivedA : public Base; class DerivedB : public Base;  /*etc...*/   and another file: BaseFactory.h  #include "Base.h"  class BaseFactory { public:   BaseFactory(const string &amp;sClassName){msClassName = sClassName;};    Base * Create()   {     if(msClassName == "DerivedA")     {       return new DerivedA();     }     else if(msClassName == "DerivedB")     {       return new DerivedB();     }     else if(/*etc...*/)     {       /*etc...*/     }   }; private:   string msClassName; };  /*etc.*/   Is there a way to somehow convert this string to an actual type (class), so that BaseFactory wouldn't have to know all the possible Derived classes, and have if() for each one of them? Can I produce a class from this string?   I think this can be done in C# through Reflection. Is there something similar in C++? How to redirect stderr and stdout to different files and also display in terminal? I want to see the output of a command in the terminal as if there was no redirection.  Also, stderr needs to be redirected to err.log and stdout needs to be redirected to stdout.log.  It would be nice to also have the exact copy of what is shown in terminal, i.e. errors printed as and when it occurs, in a separate file: stdouterr.log. Global variables in AngularJS The tablet functionality stops working after I wake my Lenovo Tablet from sleep mode (closing &amp; opening lit). The error message is "Tablet Serial Wacom Tablet (Lenovo X201) removed" (screenshot: ). In the system settings under input devices it states that "No tablet device is detected". Only a restart helps and the touch screen works again.  This error appeared only after upgrading from Kubuntu 12.04 to 14.04. In 12.04 the same error message appeared after waking from sleep mode, but then another followed that the tablet was activated again and it worked properly. Any ideas how this could be fixed? I am able to use the split command successfully to split large file into multiple smaller files. This is being achieved by following command  split -b 1G $temp_path $final_filepath   But only caveat is that these files many times contain last line which is split across 2 files. Is there any way to avoid that using split or any other command ? When should static_cast, dynamic_cast, const_cast and reinterpret_cast be used? I'm looking for a short story from about 50 years ago about a robot who escapes after being slated to be melted down and discovers while in hiding that it has evolved to have some supernatural powers. Picking a lock typically requires a DC 15 Dexterity check (Basic rules, p. 49). Likewise for manacles (p. 50), which can alternately be escaped with a DC 20 Dexterity check or broken with a DC 20 Strength check. But what happens if you fail?  The general rules for ability checks state (p. 58):     If the total equals or exceeds the DC, the ability check is a success—the creature overcomes the challenge at hand. Otherwise, it’s a failure, which means the character or monster makes no progress toward the objective or makes progress combined with a setback determined by the DM.   As a DM, how can I handle this in practice? In our last session, the players wanted to get inside a locked building to rescue people trapped inside. Picking the lock seemed like an easy enough task for the rogue, but unluckily he failed the check, and I wasn’t prepared for the consequences. There wasn’t much time pressure and no obvious reason why he couldn’t try again, so I allowed another attempt, but it just didn’t feel right.  I’m sure that similar situations will come up again, so I’d like some advice on how to deal with checks so that they don’t just turn into a tedious exercise of rolling until you succeed. I presume that  was left out of the game for good reason, but I’m not sure what to do instead. I suspect that this was a good occasion to use “progress with a setback” but that’s a fairly new thing for D&amp;D and I’m not sure how to go about it. I’m unsure when I should use setbacks versus lack of progress, and in the latter case I’m unsure when I should allow players to try again versus requiring a different approach.  For example, suppose that a manacled player tries to pick the lock and fails the DC 15 Dexterity check. Now, the player could try to pick it again, or he could try one of the other escape methods, or he could wait for somebody else to rescue him, or he could simply succeed with some setback like a minor injury. How do I choose how to proceed? Or do I let the players choose? C# - Keyword usage virtual+override vs. new What are the differences between Generics in C# and Java... and Templates in C++? I mostly use Java and generics are relatively new. I keep reading that Java made the wrong decision or that .NET has better implementations etc. etc.  So, what are the main differences between C++, C#, Java in generics? Pros/cons of each? Why do some Unicode text messages crash the iPhone OS? A Jamaican committed marriage fraud about 30 years ago by marrying a US citizen in a marriage where the groom was paid a certain amount of money to marry her. The groom got in legal trouble for an unrelated matter, and the marriage fraud was discovered and the family friend was deported back to Jamaica. She no longer has any paperwork involved with the deportation and she can’t remember any of the details. I do not know if she simply agreed to return to Jamica when the fraud was discovered, or if she made any attempts to mount any type of legal defense in the case. I do know that she was cooperative with the immigration authorities and that they did not have to come looking for her. She would like to come the USA for a two-week visit. The main purpose of the visit is for her to visit a friend (US citizen) who is terminally ill.  I have been looking at 8 U.S.C. 1182 and from my reading of it, it would seem that she would not be admissible to the US because of the previous immigration fraud. My understanding is based on the section that says:     In general.-Any alien who, by fraud or willfully misrepresenting a material fact, seeks to procure (or has sought to procure or has procured) a visa, other documentation, or admission into the United States or other benefit provided under this Act is inadmissible.   What’s not clear to me is if this means that she would be inadmissible permanently or if this would be subject to the 10 year limit.  Can anyone help provide some clarity on this?  If the ban is not permanent are there any tips to being able to increase her chances of being able to get a visa.  She intends to honestly answer all questions during her application process for a visa. why is there no non-degenerate 2-forms on 4-sphere? How to pick one number from each sorted list so that the difference between the minimum and maximum is as small as possible? Proving $6^n - 1$ is always divisible by $5$ by induction I'm trying to prove the following, but can't seem to understand it. Can somebody help?     Prove $6^n - 1$ is always divisible by $5$ for $n \geq 1$.   What I've done:  Base Case: $n = 1$: $6^1 - 1 = 5$, which is divisible by $5$ so TRUE.  Assume true for $n = k$, where $k \geq 1$: $6^k - 1 = 5P$.  Should be true for $n = k + 1$  $6^{k + 1} - 1 = 5Q$  $= 6 \cdot 6^k - 1$  However, I am unsure on where to go from here.