I don't pay much attention to them but what do the numbers to the right of my name / point score mean (like 2 / 13 / 41 below)? I know this should be super obvious but I just don't know.
I'm referring to the colored circles with numbers next to them on the top of the page, to the right of my reputation counter. What do they represent?
Is there any simple (IE: right click in Nautilus) way to password protect a particular folder/file in Ubuntu? I've got a few files containing sensitive info and I'd much prefer that if/when I leave my computer alone, they aren't accidentally accessed by someone else.  The secruty does not have to be extremely tight. My only concern is that when family/friends come over, I don't really like the idea of them looking at my bank details, accounts or, you guessed it, porn collection.  A simple, effective way to let me put my machine in the hands of someone else knowing that said machine can not cause me embarresment is the sole reason why I'd like to see this in Ubuntu. Show that $n-m$ is a multiple of 9 when $n$ and $m$ have same digits Minecraft Forge 1.7.10 will not start My minecraft will not start on only that version, I have a Windows 7 computer with Java 8u20 installed, because the latest java 7 update will not work at all(plus imma dev for other stuff).   [22:26:39] [main/INFO] [LaunchWrapper]: Loading tweak class name   cpw.mods.fml.common.launcher.FMLTweaker  [22:26:39] [main/INFO] [LaunchWrapper]: Using primary tweak class name   cpw.mods.fml.common.launcher.FMLTweaker  [22:26:39] [main/INFO] [LaunchWrapper]: Calling tweak class   cpw.mods.fml.common.launcher.FMLTweaker  [22:26:40] [main/INFO] [FML]: Forge Mod Loader version 7.10.25.1208 for Minecraft   1.7.10 loading  [22:26:40] [main/INFO] [FML]: Java is Java HotSpot(TM) 64-Bit Server VM, version   1.8.0_20, running on Windows 7:amd64:6.1, installed at C:\Program   Files\Java\jre1.8.0_20  [22:26:40] [main/INFO] [LaunchWrapper]: Loading tweak class name   cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker  [22:26:40] [main/INFO] [LaunchWrapper]: Loading tweak class name   cpw.mods.fml.common.launcher.FMLDeobfTweaker  [22:26:40] [main/INFO] [LaunchWrapper]: Calling tweak class   cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker  [22:26:40] [main/ERROR] [LaunchWrapper]: Unable to launch  java.util.ConcurrentModificationException     at java.util.ArrayList$Itr.checkForComodification(Unknown Source) ~[?:1.8.0_20]     at java.util.ArrayList$Itr.remove(Unknown Source) ~[?:1.8.0_20]     at net.minecraft.launchwrapper.Launch.launch(Launch.java:117) [launchwrapper-  1.9.jar:?]     at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.9.jar:?]  Java HotSpot(TM) 64-Bit Server VM warning: Using incremental CMS is deprecated and   will likely be removed in a future release pgfplots fillbetween with multiple curves I have a TikZ picture like this:  \begin{tikzpicture}   \begin{axis}[     axis lines=middle,     xmin=-0.5,xmax=3.5,ymin=-0.5,ymax=3.5   ]   \addplot[very thick,blue, samples=300, domain=0:3, name path=A] {sqrt(x)};    \addplot[very thick,yellow!70!red, samples=300, domain=0:3, name path=B] {9-3*x};    \addplot[very thick,red!90!teal, samples=300, domain=0:3, name path=C] {3};    \addplot[very thick,green!70!magenta, samples=300, domain=0:3, name path=D] coordinates{(1/9,-6) (1/9,6)};   \end{axis} \end{tikzpicture}     I’d like to fill the area enclosed by these four curves.  Similar questions have been answered using pgfplots’s fillbetween package, but it only seems to support filling between two curves. What are my options? Different ways to execute a shell script There are several ways to execute a script. The ones I know are: /path/to/script # using the path (absolute or relative) . script        # using the . (dot) source script   # using the `source` command  Are there any other way? What are the differences between them? Are there situations that I must use one and not another? How do I determine the size of an object in Python? I want to know how to get size of objects like a string, integer, etc. in Python.  Related question:   I am using an XML file which contains size fields that specify the size of value. I must parse this XML and do my coding. When I want to change the value of a particular field, I will check the size field of that value. Here I want to compare whether the new value that I'm gong to enter is of the same size as in XML. I need to check the size of new value. In case of a string I can say its the length. But in case of int, float, etc. I am confused. How to understand pipes When I just used pipe in bash, I didn't think more about this. But when I read some C code example using system call pipe() together with fork(), I wonder how to understand pipes, including both anonymous pipes and named pipes.  It is often heard that "everything in Linux/Unix is a file". I wonder if a pipe is actually a file so that one part it connects writes to the pipe file, and the other part reads from the pipe file? If yes, where is the pipe file  for an anonymous pipe created? In /tmp, /dev, or ...?   However, from examples of named pipes, I also learned that using pipes has space and time performance advantage over explicitly using temporary files, probably because there are no files involved in implementation of pipes. Also pipes seem not store data as files do. So I doubt a pipe is actually a file. Are there irreducible polynomials that are partially solvable by radicals? In general, polynomials of degree 5 or higher, with rational coefficients, are not solvable by radicals. There are some exceptions and trivial cases, for example $x^5-5x+12$ and $x^{100}+x^{25}+3$, respectively.  All irreducible polynomials with rational coefficients, that I am aware of, have either none or all roots that can be expressed by radicals.  Do partially-solvable irreducible polynomials exist? If they do, are there any examples known?  I mean, for example, an irreducible polynomial of $n$th degree that can be split over $Q(\sqrt{2})$ into two polynomials of 3rd and $(n-3)$th degrees, where the polynomial of $(n-3)$th is not solvable by radicals.    At  Alexander Gruber wrote:     Polynomials which are not solvable by radicals have (at least one) root that cannot be written by any combination of the operations of addition, multiplication, and the taking of nth roots.   I am not sure if he meant only reducible polynomials, and/or with non-rational coefficients, as polynomials that have "at least one" root that cannot be expressed by radicals. How to evaluate $\int_{0}^{\infty}\exp(-x^2-1/x^2)dx$? Question :  $$\int_{0}^{\infty}\exp(-x^2-1/x^2)dx=?$$  I think the answer is $\sqrt{ \pi/2 \cdot \exp(-2)}$  If I change $-x^2-1/x^2$ to $-(x-1/x)^2-2$ then the above integral becomes    $$\exp(-2)\int_{0}^{\infty} \exp(-(x-1/x)^2)dx$$   integral of $\exp(-x^2)dx$ from $0$ to infinity = square root of $\pi/2$, but then is the   integral of $\exp(-(x-1/x)^2)dx$ from $0$ to infinity=integral of $\exp(-x^2)dx$ from $0$ to infinity ? Limit of $n/\ln(n)$ without L'Hôpital's rule I am trying to calculate the following limit without L'Hôpital's rule:     $$\lim_{n \to \infty} \dfrac{n}{\ln(n)}$$   I tried every trick I know but nothing works. You don't have to prove it by definition. $$\tan(\theta_1+\theta_2+\cdots+\theta_n)=\frac{S_1-S_3+S_5+\cdots}{1-S_2+S_4+\cdots}$$  where  $S_i$ denotes the sum of product of tangent of angles taken $i$ at a time.     For example,$$\tan(\theta_1+\theta_2)=\frac{S_1}{1-S_2}=\frac{\tan\theta_1+\tan\theta_2} {1-\tan\theta_1\tan\theta_2}$$   (This formula is given  in my textbook with no derivation or background)  How to derive this? If $G$ is abelian, then the set of all $g \in G$ such that $g = g^{-1}$ is a subgroup of $G$ Prove that if $G$ is abelian then the set $H$ of all elements of $G$ that are their own inverses is a subgroup of $G$.   Naturally in an abelian group, $ab = ba$ for $a, b \in G$, however I'm not sure how to show the set elements that are their own inverses is a subgroup of $G$ using arbitrary elements. I am considering purchasing a Mac for my godson who will be using it to run Blender 2.8.  I know very little about this program.  All I can find are requirements for a Mac that will run earlier versions of Blender.  Would someone please recommend a list of requirements for a Mac (or a link to a list of requirements) that I could use to find a model that can run 2.8?  Thank you in advance for all your help! Sincerely, M. Lap How to replace a video on YouTube Macroscopic quantum phenomena and tunneling Sum of two co-prime integers I need some help in a proof: Prove that for any integer $n&gt;6$ can be written as a sum of two co-prime integers $a,b$ s.t. $\gcd(a,b)=1$.  I tried to go around with "Dirichlet's theorem on arithmetic progressions" but didn't had any luck to come to an actual proof. I mainly used arithmetic progression of $4$, $(4n,4n+1,4n+2,4n+3)$, but got not much, only to the extent of specific examples and even than sometimes $a,b$ weren't always co-prime (and $n$ was also playing a role so it wasn't $a+b$ it was $an+b$).  I would appriciate it a lot if someone could give a hand here. Tracking disk I/O by application in Windows? Isomorphism involving Eilenberg-Maclane space, Tors. Let $\pi$ be a group and let $K(\pi, 1)$ be a connected CW complex such that $\pi_1(K(\pi, 1)) = \pi$ and $\pi_q(K(\pi, 1)) = 0$ for $q \neq 1$. Does there exist an isomorphism between $H_*(K(\pi, 1); A)$ and $\text{Tor}_*^{\mathbb{Z}[\pi]}(A, \mathbb{Z})$? Integration of the cardinal sine It is said that the integral of the cardinal sine is $1$. How do I integrate the cardinal sine? $$ \int_{-\infty}^{\infty} \frac{\sin(a)}{a} \, {\rm d} a $$ Elsevier article with APA references I'm writing an article for Elsevier Journal which follows APA6e references; everything is fine except that the article starts from page 2 leaving page 1 blank with just double hyphen (==) in the middle. Here is how I write.  \documentclass[preprint,12pt,authoryear]{elsarticle} \usepackage[natbibapa]{apacite} \usepackage{float} \usepackage{hyperref} \usepackage[ruled,vlined,commentsnumbered]{algorithm2e} \journal{Expert Systems with Applications}  \begin{document} \begin{frontmatter}  \bibliographystyle{apacite} \bibliography{myrefers}  \end{document}   How Can I rectify the problem?