I see some codes that have method implementation as  public void setVariables(final int value){ this.value=value; }   why is the final keyword used in the parameter.  why not declare  public void setVariables(int value){ this.value=value; }   I understand that for classes defined inside methods that access method parameters, they have to declared final  what exactly is the benefit of having final keyword in parameter ?
I've found a couple of references () that suggest using final as much as possible and I'm wondering how important that is. This is mainly in the the context of method parameters and local variables, not final methods or classes. For constants, it makes obvious sense.  On one hand, the compiler can make some optimizations and it makes the programmer's intent clearer. On the other hand, it adds verbosity and the optimizations may be trivial.  Is it something I should make an effort to remember?
How can I prove that all rational numbers are either terminating decimal or repeating decimal numerals? I am trying to figure out how to prove that all rational numbers are either terminating decimal or repeating decimal numerals, but I am having a great difficulty in doing so. Any help will be greatly appreciated. So we have something like:  \documentclass{article} \setcounter{secnumdepth}{2} \setcounter{tocdepth}{2} \usepackage{amsmath}  \begin{document}  \tableofcontents  \section{Brushless Motor Fundamentals} \subsection{Brushless Motor Operation} \subsubsection{DC Motor Operation} Torque is generated in DC motors from the magnetic force, also known as the Lorentz force, which is produced when an electric current is passed through a coil in a magnetic field. This force is given by $F=q[E+(v\times B)]$, where $F$ is the force perpendicular to the coil, $E$ is the electric field in the coil, $B$ is the magnetic field, and $v$ is the velocity of the charged particles in the coil. From mechanics, torque is $\tau=F\times r$.  \section{Brushless Motor Fundamentals 2} \subsection{Brushless Motor Operation} \subsubsection{DC Motor Operation 2} If the electrical force is ignored and the remaining magnetic force is used, with the assumption that $v$ is perpendicular to $B$, we find that $\tau=qvBrsin\theta$.  \end{document}   How to show subsubsections and paragraphs in TOC? How do you extract IP addresses from files using a regex in a linux shell? Let $m$ be Lebesgue measure and $a \in R$. Suppose that $f : R \to R$ is integrable, and $\int_a^xf(y) \, dy = 0$ for all $x$. Then $f = 0$ a.e. This is a corollary to a proof in Bass, but I don't understand why it follows from the proof he gives. I follow everything up until the last statement. Why is it that proving that the integral is $0$ for all Borel measurable sets guarantees it is true for all Lebesgue measurable sets? Am I missing something vital about the relationship between Lebesgue measurable sets and Borel measurable sets? Statement: Let $m$ be Lebesgue measure and $a \in\mathbb R$. Suppose that $f : \mathbb R \to\mathbb R$ is integrable, and $\int_a^xf(y) \, dy = 0$ for all $x$. Then $f = 0$ a.e. Proof: We prove the conclusion first for intervals, then for unions of intervals, then for open sets, then for Borel measurable sets. For any interval $(c,d)$, we have $$\int_c^df = \int_a^d f - \int^c_a f = 0.$$ By linearity, if $G$ is the finite union of disjoint open intervals, then $\int_G f = 0$. Now, if $G$ is open, then $G$ is the countable union of disjoint, open intervals, $G = \bigcup^n_{i=1}I_i$. We have $$\int_G f = \int \lim_{n\to\infty} f \cdot \chi_{\bigcup^n_{i=1} I_i}$$ and since $f_n$ is integrable for all $n$, and $|f_n| \le f$ for all $n$, by the dominated convergence theorem, $$\int_G f = \lim_{n\to\infty} \int_{\bigcup^n_{i=1}I_i} f =0.$$ Now, if $G_n$ is a decreasing sequence of open sets converging to $H$, since $|f \cdot \chi_{G_n}| \le f \cdot \chi_{G_1}$ for all $n$, we again have by the DCT that $\int_H f = 0 = \lim_{n\to\infty} \int_{G_n}f = 0$. Finally, if $G$ is a Borel measurable set, then we know that there exists a sequence $G_n$ of decreasing, open sets, that converge to some set $H$, where $H \setminus G$ is a null set. Thus, $$\int_G f = \int_H f = 0.$$ We have found that for every Borel measurable set $G$, $\int_G f =0$. Since $f$ is real valued and measurable, $f = 0$ a.e. I have studied that  and motional emf are two different lines of thinking but are essentially same. But then, how can Faraday's paradox be explained by Faraday's law of induction? Particularly in paradoxes in which Faraday's law of induction predicts zero EMF but there is a non-zero . The wikipedia article is more confusing rather than enlightening.  I need an explanation regarding  EDIT : I wanted to know how is flux changing if faraday's law is valid . Abort Ajax requests using jQuery Is it possible that using jQuery, I cancel/abort an Ajax request that I have not yet received the response from? What do you call an 'unselfish' action made with a selfish reason? There are many examples of this, and I'd like to give a few:   A person who puts a lot of effort to help the community and earns reputation points. But that reputation is the motivation behind helping the community, not because they really want to. A student approaches a professor, and helps them in their teaching and doing research in order to have a good LOR (letter of recommendation). To a SEO, the content of the website must be good (well, this one is a little tricky, but you get the spirit.)   I'm not saying that the reputation/LOR/high-ranked is not deserved. It is. I just want to focus more on the selfish reason(s) behind that.  Any kind of answer can be accepted: single word, phrase, proverb or idiom. Is there any way to get real-time compilation for LaTeX? I would really love to have a software or tool which provided real time compilation of my LaTeX document (to be able to see the final pdf or dvi document as I type the latex code), especially for when I am drawing pictures using tikZ. So far, I know of two things, but none of them work for me. They are:   : This is only for tikZ, which would be perfect for me, but unfortunately as far as I know it only works with Ubuntu and Debian, and I use Mac OS X (so I have never actually tried it, though I did dig a lot to see whether I would be able to install on my mac and from what I see it is really what I want - I am even considering installing Ubuntu just to use it!). : This is a minor mode for Emacs. It was extremely hard to get it to work on the mac (see my quest ), and it is not all that fast. The speed is not all that big of a deal for me, but the fact that it does not work with tikZ pictures is (the nodes all collapse in one point so that the words are all one on the top of the other).   So my question is: is there a software ideally like KtikZ or another type of editor which provides real-time compilation and that I can use on my mac? I guess if you know of a Windows/Linux option I would also like to know, and the same for a way to set up a script to get the document compiled every 5 seconds or so (I am sure I have seen this written somewhere, but I don't know whether I can do it with a mac or whether it is editor/pdf viewer dependent), but what I really want is a software/tool which would work with a mac.  To be clear, I am not after something like LyX, that is, I am not after a WYSIWYG-type thing, but rather something where I can type real LaTeX and see my code, but have at the same time another window showing me the pdf (or dvi) file compiled. I see people say statement as question while speaking by raising their voice at the of it to mean it's a question.   For example consider followings.         You want to stay here? ==> Is used to mean "Do you want to stay here?"   You guys spoke to anyone? ==> Is used to mean "Did you guys speak to anyone?"      Are these really used by native speaker in casual speech? And can I write them in the same way while writing them as dialogue by putting them between quotes? Are there any special grammar rules for these kind of questions? When using the Text Editor, what is the best command to include inside a script which will abort the script at that line?  quit() and sys.exit() stop the script, but also kill Blender. When I parent an object to follow a path and animate it, I only get a linear mode animation and changing that in Grapth Editor to bezier doesn't work! How to do that? Show that $g\circ f\equiv 0$ implies $\det Df\equiv 0$, where $g(x_1,...,x_n)=x_1^5+...+x_n^5$ Let $f:\mathbb{R}^n \rightarrow \mathbb{R}^n$ be a smooth function and let $g:\mathbb{R}^n \rightarrow \mathbb{R}$ be defined by $g(x_1,...,x_n)=x_1^5+...+x_n^5$. Suppose $g\circ f\equiv 0$. Show that $\det Df\equiv 0$.  I was going to start the solution from $n=2$ and then use induction on $n$.  So, for $n=2$, $f:\mathbb{R}^2 \rightarrow \mathbb{R}^2$ is a smooth function and $g:\mathbb{R}^2 \rightarrow \mathbb{R}$ where $g(x_1,x_2)=x_1^5+x_2^5$. Then $Df=\begin{pmatrix}   f_{x_1x_1} &amp; f_{x_1x_2}  \\   f_{x_2x_1} &amp; f_{x_2x_2}   \end{pmatrix}$  But now I am stuck in proving the result. Am I in the correct track? Can anyone plese give me a hint to continue?  Ok so since $g\circ f$ is $0$, the image of $f$ is the line $x_1+x_2=0$ which has no min, max or saddle.   If det$Df(x_0)&gt;0$ and $f_{x_1x_1}(x_0)&gt;0$ OR det$Df(x_0)&gt;0$ and $f_{x_1x_1}(x_0)&lt;0$, we have contradiction.   But if det$Df(x_0)&gt;0$ and $f_{x_1x_1}(x_0)=0$, then det$Df(x_0)=0$ or, det$Df(x_0)&lt;0$(Since $f_{x_1x_2}=f_{x_2x_1}$). So this is impossible.  If det$Df(x_0)&lt;0$ we have saddle and it is impossible.   So finally we conclude that det$Df(x)=0$ for all $x$. Am I correct? Can I use mirroring to make a copy of my Database? Normality of dependent variable = normality of residuals? What to do when I get an "attempt to read or write outside of disk 'hd0'" error and Boot Repair does not solve the problem? How can I delete a (null) app in usage? In my usage list(settings>general>storage &amp; iCloud usage>manage storage), there is an app that registers as (null) with no icon, a version number that doesn't match anything I've previously downloaded, and it's taking up storage space. I first noticed it about a week or two ago. And no, I can't download recent apps to find the one that it is, because I downloaded multiple apps recently, and didn't notice the (null) app until my storage was critically low and I was looking to delete something. I am running iOS 9.2.1 on an iPhone 5C. TP-Link Archer T3U Plus USB adapter Cannot make this wireless adapter work on Ubuntu 20.04... please help. I've tried this:  and now lsusb sees the device, but still doesn't work. lsusb: Bus 002 Device 006: ID 2357:0138 TP-Link 802.11ac NIC uname -r: 5.4.0-39-generic Edit: It works on my other computer with Ubuntu 18.04 using T2U Plus driver from here:  But it does not work with Ubuntu 20.04... sudo modprobe 88x2bu: Gives nothing. modinfo 88x2bu | grep -e version -e 0138 : version:        v5.6.1_30362.20181109_COEX20180928-6a6a srcversion:     9C5282368F93050B7206C8D parm:           rtw_chip_version:int  dmesg | grep 88x2 : [ 8087.334869] 88x2bu: loading out-of-tree module taints kernel. [ 8087.336610] 88x2bu: module verification failed: signature and/or required key missing - tainting kernel [ 8087.341389] usbcore: registered new interface driver rtl88x2bu Is it possible to create image data and save to a file from a script What is a bus error? What does the "bus error" message mean, and how does it differ from a segfault? Why can't you get awarded the bounty for answering your own question? Consider this question on .  I put out a 200 bounty on the question, but did not get an answer from anyone other than myself that worked.    In fact, my answer is also the highest up-voted on it at this point.  I know that allowing OP's to retract a bounty can be a slippery slope; in fact I think that once the bounty is put up it should stay up.  But why not allow the OP to answer their own questions with a bounty and reward it to them if they receive the same up-votes as others?  Yes, I am fully aware that bounties are a risk.  People will use them for numerous reasons such as trying to draw extra attention to their issues.  However, in my specific question, the only valid answer is the one that I gave.  Had it been anyone else's question, I would have received the bounty, but since it was my own I did not.