If someone keeps entering and exiting my bedroom, and I want him to stop. Should I say:   don’t come in and out of my bedroom.   Or   don’t go in and out of my bedroom.   Is this just a case of directional difference between the verbs ‘come’ and ‘go’, or is it that only one of them fits as part of an idiomatic construction?  Also, apart from ‘in and out’, are there any other expressions/phrases that can express the same idea succinctly?
Why is it "come" rather than "go" ?
Past participle vs being+past participle How to make a WPF application a 30 day trial version, and make it licensed using product key? Define $S\equiv\{ x\in \mathbb{Q}\mid x^2<2\}$. Show that $\sup S=\sqrt{2} $. How to evaluate $\int_{0}^{+\infty}\exp(-ax^2-\frac b{x^2})\,dx$ for $a,b>0$ Given a subset $A$ of $\mathbb{R}^{n}$, a point $x \in \mathbb{R}^{n}$ is said to be in the boundary of A if and only if for every open rectangle $B\subseteq\mathbb{R}^{n}$ with $x\in B$, $B$ contains both a point of $A$ and a point of $\mathbb{R}^{n}\setminus A$.  My question is from Spivak's Calculus on Manifolds: Construct a set $A \subseteq [0,1]\times [0,1]$ such that $A$ contains at most one point on each horizontal and vertical line but has boundary equal to $[0,1]\times[0,1]$. I'm going down my huge backlog of unplayed Steam games and I'm thinking the best way to tackle the list is to go through the shortest games first and then concentrate on the 20+ hour ones. I'm wondering if there's a website or something else that has an estimated amount of gameplay time for games.   Is there anything like that? How can I recover a game center account where I forgot ID and password? A long time ago, I made a game center account to which I attached my CoC village. This account hasn't been used anymore, and I have forgotten the ID and the password.  Now I want to transfer that game to my new phone which has a new game center ID, but need a transfer code from the old account to do so. Is there a way to recover my old game center account details? Prove that $A \smallsetminus (A \smallsetminus B) = A \cap B$ $A$ and $B$ are any sets, prove that $A \smallsetminus (A \smallsetminus B) = A \cap B.$ This formula makes sense when represented on a Venn diagram, but I am having trouble with proving it mathematically.  I have tried letting $x$ be an element of $A$ and continue from there, but it doesn't seem to work out as a valid proof anyways.   Could anyone please point me in the right direction?  Many thanks. I am currently in need of using apt-get on a chroot directory. The setup is the following.  I have a chroot setup with schroot. This chroot environment needs to be stripped down as much as possible. Therefore I am planning to remove apt-get and commin from the chroot environment.  I know that Gentoo has the possibility to use portage on a different root directory. Is this possible to set a different root directory for apt.get to install software into my chroot directory?  Thanks in advance Solving linear congruences by hand: modular fractions and inverses When I am faced with a simple linear congruence such as  $$9x \equiv 7 \pmod{13}$$ and I am working without any calculating aid handy, I tend to do something like the following:  "Notice" that adding $13$ on the right and subtracting $13x$ on the left gives: $$-4x \equiv 20 \pmod{13}$$  so that $$x \equiv -5 \equiv 8 \pmod{13}.$$  Clearly this process works and is easy to justify (apart from not having an algorithm for "noticing"), but my question is this: I have a vague recollection of reading somewhere this sort of process was the preferred method of C. F. Gauss, but I cannot find any evidence for this now, so does anyone know anything about this, or could provide a reference? (Or have I just imagined it all?)  I would also be interested to hear if anyone else does anything similar. Meaning of convolution? Table of Contents for poetry collection (ConTeXt) I'm getting stumped about how to generate the ToC for this book. I'm about to give up and just do it by hand. The author wants to include a lot of structural information that isn't present in the actual text, and none of the numbers "roll over" as they're want to do in ConTeXt.  This is the desired effect:    Narrator 1...      FIRST PART: PART SUBTITLE  1). First Poem // First Poem (Spanish title) . . . . . . . . . . . . . . . . .    1     Author of Poem (b. XXXX d. XXYY)  2). Second Poem // Poema Secunda . . . . . . . . . . . . . . . . . . . . . . .    3     Author of Poem    Narrator 2...  3). Third Poem // Third Poem . . . . . . . . . . . . . . . . . . . . . . . . .    5     Author      SECOND PART: Part 2  4). Fourth Poem // Fourth Poem . . . . . . . . . . . . . . . . . . . . . . . .    7     Author    Narrator 3...   The problems I have essentially boil down to these:   There is this weird "narrator" concept that doesn't seem to contain or be contained by the part/poem structure. A new part doesn't imply a new "narrator" and a new "narrator" doesn't imply a new part. I need to aggrandize each title with the title in translation and the author, and I want to typeset them nicely. I need poems to continue counting up across parts.   I see basically three approaches:   Make each poem a chapter and customize the appearance with \setuphead[chapter][....]. Then use \writebetweenlist[chapter] to add the Narrator and author information. Make a new list with \definelist[poem] and \definecombinedlist[content][part,poem]; continue using \writebetweenlist[poem] to insert the author and Narrator. This feels like the most conceptually valid option, but I think I'll still need a lot of customization. Forget all about ConTeXt and switch to plain TeX, use eplain's writetocentry system. Make it look right and forget maintainability. Consider the following MWE:  \documentclass{article} \usepackage{pstricks} \begin{document} A \end{document}   It produces the error  Runaway argument? ] {pgffor.code.tex}  ! Paragraph ended before \ProvidesPackageRCS@i was complete. &lt;to be read again&gt;                     \par  l.11   How do I fix this? Does the verb &quot;provide&quot; always have to be used with &quot;with&quot;? For example,  Can you provide me with some good examples? Can you provide me some good examples? Can you provide some good examples?  I suppose it's a transitive verb, isn't it? Moreover, is the following type of usage correct?  You should provide food for your dog before you go on vacation.  If you could give me some good examples regarding &quot;provide&quot; with different types of usage, I'd appreciate that. Homotopy functions I'm new here. Can anyone give me a hint in this problem? Please.  Let $X$ be a topological space. If $f,g$ are continuous function of $f,g\colon X\to S^n$  which $f(x)\neq -g(x)$ for all $x$ in $X$, show $f$ and $g$ are homotopics. I try to show a homotopy using $$q(x) = \frac{f(x)+g(x)}{\|f(x)+g(x)\|}$$ it's well defined, but i'm stuck. I want to schedule my script for last Saturday of every month. I have come up with the below:  45 23 22-28 * *  test $(date +\%u) -eq 6 &amp;&amp; echo "4th Saturday"  &amp;&amp; sh  /folder/script.sh    Is this correct or I need to change it? I can't test it right now as it will be invoked only on last saturday. Please advise.  I have the below for last sunday of every month but i can't understand much of it. The first part gives 24 which is sunday and after -eq gives 7 which i don't know what it means:  00 17  * * 0 [ $(cal -s | tail -2 | awk '{print $1}') -eq $(date | awk '{print $3}') ] &amp;&amp; /folder/script.sh   Can i modify the above to get last saturday?  With Romeo's help I was help to come up with the below answer:  00 17 * * 6 [ $(cal -s | tail -2 | awk '{print $7}') -eq $(date | awk '{print $3}') ] &amp;&amp; /folder/script.sh What techniques are available for collapsing (or pooling) many categories to a few, for the purpose of using them as an input (predictor) in a statistical model?    Consider a variable like  (discipline chosen by an undergraduate student). It is unordered and categorical, but it can potentially have dozens of distinct levels. Let's say I want to use major as a predictor in a regression model.  Using these levels as-is for modeling leads to all sorts of issues because there are just so many. A lot of statistical precision would be thrown away to use them, and the results are hard to interpret. We're rarely interested in specific majors -- we're much more likely to be interested in broad categories (subgroups) of majors. But it isn't always clear how to divide up the levels into such higher-level categories, or even how many higher-level categories to use.  For typical data I would be happy to use factor analysis, matrix factorization, or a discrete latent modeling technique. But majors are mutually exclusive categories, so I'm hesitant to exploit their covariance for anything.  Furthermore I don't care about the major categories on their own. I care about producing higher-level categories that are coherent with respect to my regression outcome. In the binary outcome case, that suggests to me something like linear discriminant analysis (LDA) to generate higher-level categories that maximize discriminative performance. But LDA is a limited technique and that feels like dirty data dredging to me. Moreover any continuous solution will be hard to interpret.  Meanwhile something based on covariances, like multiple correspondence analysis (MCA), seems suspect to me in this case because of the inherent dependence among mutually exclusive dummy variables -- they're better suited for studying multiple categorical variables, rather than multiple categories of the same variable.  edit: to be clear, this is about collapsing categories (not selecting them), and the categories are predictors or independent variables. In hindsight, this problem seems like an appropriate time to "regularize 'em all and let God sort 'em out". Glad to see this question is interesting to so many people! How was Jon Snow able to kill the White Walker in S05E08? GCD in a PID persists in extension domains Let $R$ be subring of integral domain $S.$ Suppose $R$ is $\text{PID}.$ Let $a\in R$ be a greatest common divisor of $r_1,r_2$ in $R$. ($r_1,r_2 \in R$, not both zero). Could anyone advise me on how to prove $a$ is greatest common divisor of $r_1,r_2$ in $S?$   Hints will suffice, thank you. Start TOC from chapter 1 and also page numbering