I am attempting to copy files based on their modified date, as the file names do not include the date in them. Coincidentally, the files are the 22 newest files in the directory, so if I run the command ls -lt | head -22, the outputted files are exactly what I want to copy.   I had read , but the accepted answer didn't seem to work in Terminal, and it isn't exactly filtering by date, just by head.   I am running macOS Sierra 10.12.5.
How can I copy the 5 newest files from a directory to another in a "new to old" order.
How to install Ubuntu on a Mac and keep OSX? Could anyone provide a concise step by step instruction on how to install Ubuntu 12.04 on a Mac OS X Lion?  I have read that Ubuntu corrupts the EFI file so I would like to hear from those who have successfully done it. verb or adjective in "The blue page is *stapled* to the red page"? In Windows 7, I know you can do Windows + Left to put a window in the left half of the screen.  Is there a feature that will do top and bottom? Current code is:  \begin{enumerate}[label=LEVEL \arabic{*},leftmargin=*]     \item Description of Level 1 \quad L1 \\ \emph{more text}     \item Description of Level 2 \quad L2 \\ \emph{more text}  \end{enumerate}   but the \quad does not align L1 and L2 uniformly vertically. I want to replace \quad with a tab but the tabbing environment does not allow mixing with an enumerate! Why does the following hold:  \begin{equation*} \displaystyle \sum\limits_{n=0}^{\infty} 0.7^n=\frac{1}{1-0.7} = 10/3\quad ? \end{equation*}  Can we generalize the above to      $\displaystyle \sum_{n=0}^{\infty} x^n = \frac{1}{1-x}$ ?   Are there some values of $x$ for which the above formula is invalid?  What about if we take only a finite number of terms? Is there a simpler formula?     $\displaystyle \sum_{n=0}^{N} x^n$   Is there a name for such a sequence?    This is being repurposed in an effort to cut down on duplicates, see here: Coping with  duplicate questions.  and here: . Symbolic links error while creating Ubuntu UEFI bootable USB I have tried to create UEFI bootable USB drive within Ubuntu 14.10 (Startup disk creator didn't help nor I am interested in using it.). I have formated USB with FAT32 and GPT. So the only thing left to do would be just to copy all files from ISO to USB. That method worked when it comes to Linux Mint 17.1 and Clonezilla live CD, but when I tried to create bootable USB for Ubuntu 14.04 or Kubuntu 15.04 beta 1 there was an error copying files. Actually, on several occasions (4 or 5) pop-up window appeared.   After ignoring this errors, both Ubuntu and Kubuntu USB boot-up just fine, with no apparent problems in Live mode.   Can someone please elaborate what this symbolic links presents? Will this cause some problem when OS is installed? Prevent text selection after double click How to select distinct field values using Solr? In the recent post , Werner helped me to redefine a proof environment which can be hidden by an optional boolean argument (showProof). Without an argument, somehow the line/paragraph breaking is not correct. How can one fix this?  \documentclass{scrartcl}  \usepackage{ifthen} \usepackage{environ} \usepackage{amsthm}  \newboolean{showProof}% for showing proofs \setboolean{showProof}{true}% setting the switch \newif\ifstarttheorem  % proof environment (with hide feature) \makeatletter \providecommand{\env@proof@save@env}{} \providecommand{\env@proof@process}{} \RenewEnviron{proof}[2][showProof]{   \gdef\@tmp{#1}%   \ifthenelse{\boolean{#1}}{\par\pushQED{\qed}%     \normalfont\topsep2\p@\@plus2\p@\relax     \trivlist\item[\hskip\labelsep\sffamily\bfseries Proof~#2]\gdef\mycurrenvir{proof}\global\starttheoremtrue\mbox{}\hfill\\*\ignorespaces     \BODY}{\ignorespaces} }[\ifthenelse{\boolean{\@tmp}}{%   \gdef\mycurrenvir{\relax}   \popQED\endtrivlist\@endpefalse }{\ignorespacesafterend}] \makeatother  \begin{document} Just some text \begin{proof}   Just some text in a standard proof. As we can see, there is a problem. \end{proof} \begin{proof}[false]   Proof with optional argument set to \texttt{false}. This proof correctly does   not appear. \end{proof} \begin{proof}[showProof]{(Heading)}   Proof with optional argument (\texttt{true}) and second argument ``(Heading)'' \end{proof} \end{document} From my old HD (Ubuntu 16.04) I copied ~/.thunderbird and other programs to the new disk with Ubuntu 18.04 installed. All went good. I tried to install Opera. The installation was unsuccessful, a window asking something was held. After that Thunderbird Local Folders -> Inbox (only) was invaded by large icons like this screenshot  Flowers, plants, trucks and others. I restarted but those images are still there. Opera was successfully installed. What can I do to remove them? I came across this example when trying to mount a usb device inside a openvz container and I have never seen the construct in the second line before. Can you explain what it signifies?  #!/bin/bash . /etc/vz/vz.conf Degree of minimum polynomial at most $n$ without Cayley-Hamilton? javascript document.getElementsByClassName compatibility with IE How to prevent different checksums for different typesets DBRefs (Mongo Document references) not fetched eagerly `du -b` shows different size than `ls` Want to install Ubuntu on Chromebook Find the tangent lines to the graph of $x^2+4y^2 = 36$ that go through the point $P=(12,3)$ I was solving a few problems from a textbook and I came across this one:     Find the tangent lines to the graph of $x^2+4y^2 = 36$ that go through   the point $P=(12,3)$   I could find the tangency points $$ but my solution was completely messy (I had four equations that I had to go back-and-forth with.  Is there an elegant/simple solution to that?  Tangency points:  $$P_1 = (0,3)$$ $$P_2 = \left( \frac{24}{5} , 3-\frac{24}{5} \right)$$ Inspired by this Hagon Von Eitzen's answer( ) I started investigating how I could express natural numbers as differences of squares. Using the method explained in the solution, I investigated natural numbers up to $60$ manually. I observed the following:  There is no way to express numbers of the form $4k+2$ as a difference of two squares.  2.There is one and only one way to express prime numbers (except $2$) as a difference of two squares.  The smallest number that can be expressed as a difference of two squares in two different ways is $15$ and the smallest number that can be expressed as a difference of two squares in three different ways is $45$.  As, $15= 8^2-7^2=4^2-1^2$. $45=23^2-22^2=9^2-6^2=7^2-2^2$. I could prove point $2$ easily but could not prove point $1$. Also I am interested in knowing how I could find the smallest natural number that could be expressed as a difference of two squares in four different ways without manual calculation. Ubuntu 14.04 Wireless not working: no network interface. Atheros [168c:003e] device