How to draw a side line in table (Using multirow will exceed the width)
How to draw a side line in table
Best way to extract a subvector from a vector? Suppose I have a std::vector (let's call it myVec) of size N.  What's the simplest way to construct a new vector consisting of a copy of elements X through Y, where 0 &lt;= X &lt;= Y &lt;= N-1?  For example, myVec [100000] through myVec [100999] in a vector of size 150000.  If this cannot be done efficiently with a vector, is there another STL datatype that I should use instead? Returning a const reference to an object instead of a copy When we canonically quantize the scalar field in QFT, we use a Lorentz invariant integration measure given by $$\widetilde{dk} \equiv \frac{d^3k}{(2\pi)^3 2\omega(\textbf{k})}.$$  How can I show that it is Lorentz invariant? Can't launch graphical apps from terminal after updating to 15.10 I am a non-EU national, permanent UK Resident. Recently, my work issued me with a multiple Schengen visa with Norway as the first (main) point of entry. Now I want to go on holidays to Greece - do I need to apply to Schengen visa again, as Greece is not Norway and I am not going there for work? When do you use the "this" keyword? How do I minimize total cost of separate flights to the same destination plus optionally accommodation? My girlfriend and I are currently living in different countries, and meet occasionally for a few days every month or so. We don't really care all that much where we are going, as long as we don't need a visa (we're both in EU), just so we are at the same place and time for a couple of days.   In short:     I'm flying from airport AAA, she's flying from airport BBB, we need to find an airport XXX (not a euphemism!) which is cheapest to fly to overall.   Bonus task: Flights are first and foremost, and we could live with a somewhat more expensive accommodation as long as we can get in and out easily. Since the accommodation cost is comparable to flight cost for such a short stay, we'd like to have some sort of rough idea what we're going to pay for a certain type of accommodation, for example three-star hotel. Getting polygon shapefile node coordinates and point order Showing that the set of fixed points is a smooth manifold Let $M$ be a smooth manifold and Let $G$ be a finite group acting on $M$ by diffeomorphisms. Show that the set of fixed point $F=\{m \in M: g.m=m \}$ is a smooth manifold. I am unable to deal with the set of fixed points. It doesn't seem to be an open set. It would have been trivial if it was open. Any hints? NSXMLParser chokes on ampersand & Let $F,G,H$ be groups such that $F\trianglelefteq G \trianglelefteq H$.  I am asked whether we necessarily have $F\trianglelefteq H$. I think the answer is no but I cannot find any counterexample with usual groups. Is there a simple case where this property is not true? Coming from Windows I have gotten extremely used to the Windows Snap feature, which resizes a window when it's dragged to the screen edges.  However, it's not built into OS X. Are there any 3rd party utilities that add this functionality? Given a list ["foo", "bar", "baz"] and an item in the list "bar", how do I get its index (1) in Python? Where do I ask where to ask? If I have a specific question I want to ask about, but I don't know which Stack Exchange site would be on topic for asking that question, where can I ask where to ask that question?  Is there any generic place where we can ask for advice? Is it here?  This is not about a specific question but in general.  For example: "Where should I ask for advice about fishing?", or if I need to know where I should ask "What would be the best fishing rod to fish for salmon?" (regardless of how good/bad these examples are) When I want to move a file to the Trash, Nautilus give me an message saying this:     You can't move example.file to the trash can. Do you want to remove it immediately?   I can give you this photo but it's in Spanish How did the house elves start serving wizards? How/Why/When did the house elves start serving wizards? I tried on my own to find the answer but I couldn't find anything relevant to my subject but I am bad at searching. How to call a constructor on an already allocated memory? How can I call a constructor on a memory region that is already allocated? QCompleter Custom Completion Rules Meaning of "kernel" In analysis, there are at least three kinds of "" concepts:   In probability theory, there is a concept called , also called probability kernel, from one measure space $X$ to another $Y$. It is actually a family of measures on $Y$, indexed by members of $X$. It can transform a measure on $X$ to a measure on $Y$, in terms of integration.  A special case is  of probability density function in statistics, where the  is actually a probability kernel. In real/complex analysis, there is a concept called  from a product space $X \times Y$ to $\mathbb{R}$ or $\mathbb{C}$. It can transform some special function: $X \to \mathbb{R}$ or $\mathbb{C}$ to another one:$Y \to \mathbb{R}$ or $\mathbb{C}$. This is used for defining integral transformation In Hilbert space theory, there is concept called , which is a family of bounded mappings for a family of Hilbert spaces. For every two Hilbert spaces $X$ and $Y$ in the family, there are exactly two members of the kernel, one mapping from $X$ to $Y$ and the other from $Y$ to $X$.   I wonder    Are they related concepts, since they seem to share some indescribable similarity? Can they be unified?   In particular, the first two are similar to each other as the kernels induce transformations on measures and on functions in terms of integrals.  It is however not obvious to me how the third one, i.e. the Hilbert space one, is related to the second one. Are they related to the  concepts? Or even to the  concept?   I feel like some insights and references for catching the general ideas shared across as many kinds of "kernels" as possible.  Thanks and regards! I found several very-close-to-duplicate questions/answers. However, I want to restate some questions and discuss the answers from these questions.  Here the questions which I found:         I find it quite unfair that super simple questions and their answers upvote give the same amount of reputation points per upvote as complex questions. I think reputation points should be much closer linked to contribution. And I think that contribution in answering/asking a simple question (both in time, value and time saved to other developers) is way less than for some more complex questions.   Why doesn't Stack&nbsp;Overflow change this?  I saw several common answers:     if you change the game, then the only result is that people will game it differently.   I agree only partly with this. Sure, people will always game the system. However, any improvement can be rejected based on this argument. I believe if there is an obvious problem, it makes sense to fix it. And it looks like this question was asked number of times (meaning that it's not only me thinking that it should be changed).     Reputation is NOTHING more than an INCENTIVE to contribute.   Again. I agree only partly. Reputation doesn't have any real value (it can't be converted to anything). However, let's be honest. People are competitive and people like to have some measurement stick and most of software developers want to have a fair game. Based on this, reputation isn't NOTHING, reputation is very important tool which makes Stack&nbsp;Overflow popular. Calculating reputation one way or another way may lure or discourage people from participating.     Esoteric questions are only of interest to people working with that item.   I believe one of the biggest values of Stack&nbsp;Overflow that it contains a lot of information which is hard to find somewhere else.  So, sure, there are some rare questions which aren't valuable to the whole community. But, I would say that a question which saves 25 people a day of work (complex question) is more valuable than a question which saves a 1000 people 3 minutes of googling (simple question).  My summary:  I believe it makes sense to change a system a little bit. The simplest way would be the ability to mark a question as trivial. If some number of people marked the question as trivial (let's say 10), all upvotes for this question/answers become less valuable (for example, 1 or 2 points, instead of 5). This will close this gap.