How to compile quickly without continously having to type the whole story of -wall -werror and all those other flags. I know how to use them, but it is a little bit of annoying if I have to type it again and again. Maybe this is asked before, but I couldn't find it.
I would like to create an alias to rm command in order to have a confirmation message after executing this command. So I am creating an alias like this alias rm='rm -i'. But as far as I know this is a temporary alias and it lives until you close the terminal.  As it is explained  to save alias permanently I need to execute ~/.bash_aliases or ~/.bashrc commands in terminal and add my alias there. But when I execute ~/.bashrc I get following error message :  bash: /home/bakhtiyor/.bashrc: Permission denied   When I run ~/.bash_aliases I get another error message like this:  bash: /home/bakhtiyor/.bash_aliases: File or directory doesn't exist.   What is the actual problem and how can I solve it?
Whenever both my roommate and I use the wifi in a certain room in our apartment, it slows dramatically for me. It doesn't slow for him. If he uses it in another room, it's fine; if I use it in another room together with him, it's fine; it's just in this particular room. Does anyone know of a reason this could be? Boarding a train in India at another station I have booked a ticket on a train from Mumbai to Chennai and boarding at Pune. Since my schedules have changed, I will be in Mumbai on that day. Can I board the same train in Mumbai in my own ticket and claim the seat/berth? How to successfully put a bibliography in a report on TexShop? I'm trying to put a bibliography in my LaTeX document, but I get various errors when I run it in BibTeX (saying no \citation found etc.), and no bibliography is printed in the PDF when I typeset it in LaTeX. My code reads as follows:  \documentclass[12pt]{report} ... \usepackage{biblatex} \addbibresource{SUSYBib.bib} ... \begin{document} ...\cite{1}... ...\cite{2}... \nocite{*} \printbibliography \end{document}   And my .bib file reads as  @book{1, title={The Schrödinger Equation}, author={F. A. Berezin, M. A. Shubin}, year={1983}, publisher={Moscow State University, Moscow}, pages={57-59} } @book{2, title={An Introduction to Measure Theory}, author={Terence Tao}, year={2011}, publisher={American Mathematical Society}, pages={91} } Wrapper for package managers There are a lot of language-specific package managers like cpan for perl, cabal for haskell etc. When we want to install some software, it can sometimes be installed from a corresponding repo, with installation instruction just like (say, ) npm install yaxy or cpan something or cabal install something.   These package managers have slightly different syntaxes, they all need root privileges and/or custom setup, or (in case of Yaxy) just a newer version of interpreter (nodejs packaged by Ubuntu was too old to run it).  Is there a wrapper for different package managers that unifies/automates setup for different package managers?  Edit: what I want is a way to execute installation command like that npm install yaxy and make it working without manual installing system npm+nodejs, getting non-functional executable, finding the simplest way to install fresher nodejs on my system, reinstalling... Is it better in C++ to pass by value or pass by constant reference? Is it better in C++ to pass by value or pass by constant reference?  I am wondering which is better practice.  I realize that pass by constant reference should provide for better performance in the program because you are not making a copy of the variable. What is the proper way to explain the twin paradox? The paradox in the  is that the situation appears symmetrical so each twin should think the other has aged less, which is of course impossible.  There are a thousand explanations out there for why this doesn't happen, but they all end up saying something vague like it's because one twin is accelerating or you need general relativity to understand it.  Please will someone give a simple and definitive explanation for why both twins agree on which twin is younger when they meet for the second time? AMT stock option scenario Sequences or 'chains' of adjoint functors Suppose we have (some categories and some functors such that) $F_1$ is left adjoint to $G_1$, $G_1$ left adjoint to $F_2$, $F_2$ left adjoint to $G_2$. Will $F_1$ then be equal to $F_2$ (and $G_1$ to $G_2$)?  Or can there exist arbitrarily long 'chains' of adjoint functors that do not trivialize? Why is it that logistic regression becomes unstable when classes are well-separated? What does well-separated classes mean? I would really appreciate if someone can explain with an example. How can I get the size of an array from a pointer in C? I've allocated an "array" of mystruct of size n like this:  if (NULL == (p = calloc(sizeof(struct mystruct) * n,1))) {  /* handle error */ }   Later on, I only have access to p, and no longer have n. Is there a way to determine the length of the array given just the pointer p?  I figure it must be possible, since free(p) does just that. I know malloc() keeps track of how much memory it has allocated, and that's why it knows the length; perhaps there is a way to query for this information? Something like...  int length = askMallocLibraryHowMuchMemoryWasAlloced(p) / sizeof(mystruct)   I know I should just rework the code so that I know n, but I'd rather not if possible. Any ideas? Is it possible to add entries to the bibliography based on keyword using Biblatex/Biber and within the document code? I would like to print a bibliography which includes all entries with a certain keyword (and possibly some additional entries).  I know that I can filter by keyword when I print the bibliography using  \printbibliography[keyword=&lt;keyword&gt;]   but this will only print entries which I have cited. I could, of course, use  \nocite{*}   to add all entries to the bibliography and then print just those I want.  However, this will make my .bbl file huge as my database is enormous.  Another possibility is to use Biber or another tool to prepare a document-specific .bib file containing only those entries with the keyword. However, this would need to be recreated if additional entries with the keyword are added to my main database files.  Here's an MWE to play with, annotated to indicate the way I'd like it to work ;), and the disadvantages of the way it (almost) works.  The issue of excluding explicitly cited entries is less of an issue for me. The thing I'd really like to work around is adding the entire database contents to the .bbl.  \RequirePackage{filecontents} \begin{filecontents}{\jobname.bib} @book{new-stuff,     author          =   {Watt, Brian},     title           =   {Happy Times with Penguins},     publisher       =   {Harvard University Press},     address         =   {Cambridge, MA},     year            =   1995,     pagination      =   {section},     keywords        =   {happy}} @book{den-coll,   author                =   {Till, Jr., Dennis E.},     booktitle           =   {Penguin Land and Further North: Human Influence},     title               =   {Penguin Land and Further North: Human Influence},     publisher           =   {Oxford University Press},     year                =   2008,     address             =   {Oxford and New York},     keywords            =   {penguin, human}} @book{old-stuff,   author                =   {Harvey, Jr., Dennis E.},     booktitle           =   {Penguin Land and Further North: Human Influence},     title               =   {Penguin Land and Further North: Human Influence},     publisher           =   {Someone \&amp; Daughters},     year                =   1567,     address             =   {Oxford},     bookpagination      =   {paragraph},     keywords            =   {penguin}} \end{filecontents} \documentclass{article} \usepackage[defernumbers=true]{biblatex} \bibliography{\jobname} \begin{document}  \cite{old-stuff}  % what I would like to work % \nocite[keyword=happy] % \printbibliography  % what does work - except that \cite{old-stuff} is ignored and, more importantly, den-coll is added to the .bbl \nocite{*} \printbibliography[keyword=happy]  \end{document} I'm looking for mathematics books, courses + exercises for high school level. My daughter was high school certificated but she has stopped her studies for 5 years. She would like to be involved in new educational program but she needs to restore her mathematic capabilities.  Could you help me to identify which mathematics books can help her?  Thanks a lot for your reply,  FR. Is there any event that fires when WPF animation ends? Idiom: People caring about minor stuff while something terrible is happening Imagine a situation in which the whole place is on fire, a bomb is about to explode, everyone is running for their lives and someone is checking his looks on the mirror... pretty inappropriate for the situation, don't you think? I'm looking for an idiom or colloquial/slang/informal expression to describe such an indifferent stance. Positive integer multiples of an irrational mod 1 are dense I'm not sure how to solve this one. Thank you!  $2.$ For any $\alpha\in \mathbb R$ we define $$\lfloor \alpha \rfloor = \max_{n\in\mathbb Z}\{\,n\mid n\leq \alpha\,\}$$ and $$\alpha\bmod 1 = \alpha - \lfloor \alpha \rfloor$$ Let $\alpha$ be irrational. (a) Given $n\in\mathbb N$ show that $\{\,k\alpha\bmod1\mid k\in\mathbb N\,\}\cap\left[0,\frac{1}{n}\right]\neq\emptyset$ (b) Prove that $\{\,n\alpha\bmod 1\mid n\in\mathbb N\,\}$ is dense in $[0,1]$. Let $x$ be transcendental over $F$. Let $y=f(x)/g(x)$ be a rational function. Prove $[F(x):F(y)]=\max(\deg f,\deg g)$ Let $F$ be a field and $x$ transcendental over $F$. Let $y=f(x)/g(x)$ be a nonconstant rational function with relatively prime polynomials $f,g\in F[x]$. Prove $[F(x):F(y)]=\max(\deg f,\deg g)$.  My attempt: By replacing $y$ with $\frac{1}{y}$ if necessary we assume $\deg g\geq\deg f$. By the Euclid algorithm we assume $\deg g&gt;\deg f$. Then $\deg g=\max(\deg f,\deg g)$, let $n=\deg g$. Let $R(t)$ be this polynomial $$R(t)=yg(t)-f(t)=\frac{f(x)}{g(x)}g(t)-f(t)$$ Then $\deg R=\deg g=n$ because $n=\deg g&gt;\deg f$. The coefficients of $R(t)$ lie in $F(y)$ and hence $R(t)\in F(y)[t]$. Clearly $R(x)=0$.  Now I only have to prove $R(t)$ is actually the minimal polynomial of $x$ over $F(y)$. I believe the next step is to obtain a contradiction that $R(t)$ being reducible can lead to $f,g$ being not coprime, but I can't figure out how to do that.  P.S. A hint is preferred over a full answer. Why is my camera limited to a shutter speed of 1/250th when the flash is up? Sometimes in bright backlight and with large aperture (f2.8) I want flash at high shutter speeds.  But when I pop the flash up on D7000 it caps the shutter speed to 1/250th, which overexposes the shots and makes everything look like a nuclear bomb just went off.  What's the logic behind the limiting of the shutter speed when using flash? Is there anything I can do to get flash  + faster shutter speeds? Does $G\oplus G \cong H\oplus H$ imply $G\cong H$ in general? How to install Python 3.6? I'd like to install the latest Python, which is 3.6 at the time of this post. However, the repository is saying that Python 3.4.2 is the newest version.  I've tried:   $ sudo apt-get update $ sudo apt-get install python3  python3 is already the newest version.  $ python -V  Python 3.4.2   To upgrade to Python 3.6 on my Windows workstation, I simply downloaded an exe, clicked "next" a few times, and it's done. What's the proper and officially accepted procedure to install Python 3.6 on Debian Jessie? Can I disable GNOME legacy tray in 17.04?