Getting the last characters of a string
Understanding slice notation
So basically, I'd like to use iwconfig to connect to my wifi network when I'm not inside X. But I just don't see a way to do it in the man page. Any idea? Induced metric on a null hypersurface Consider a metric $g_{\mu\nu}(x)$ and a hyper surface ${\cal H}$ defined by $~f(x) = c$. One (or at least I) usually finds the "induced metric" on ${\cal H}$ by solving$~f(x) = c$ for one of the coordinates and plugging it back into the metric to give us $\gamma_{ij}$. For null hypersurfaces, I seem to be finding that the resultant induced metric is singular.         Is it true in general that the induced metric as defined above is singular on a null hypersurface?   How does one define the induced metric on a null hypersurface? Asking on Multiple Sites: "Soft-Migration" See also:   Many of the newer sites have a certain degree of overlap. With the creation of Chem.SE, I noticed quite a few questions on Physics.SE which could have benefited from the chem community and vice versa. There also are a few that could benefit from bio.SE.. Now these questions don't warrant a migration. They can be double-posted, but this doesn't lead to a smooth experience. Even when cross-linked, changes to either post (new answers,new comments,etc) aren't effectively relayed to the other site, and the two questions are just that-- two, separate questions. One solution that came to my mind was a &quot;soft migration&quot; option for mods. By this, a question on site A stays on site A. But, it appears in the site B question list as well. Edits/answers should bump it. Basically, there will be a placeholder item in the questions list of site B. It shows the votes/views/answers of the post on site A, along with the tags (maybe stylized differently). These should be an unobtrusive way to quickly identify what the site is. The post should also be bumped whenever the post is bumped on Site A, and it should display the rep/time/etc of the bumping user as usual. Here's a quick mockup of what happens on the site B question list:  Without being obtrusive or in-your-face (stuff like [migrated] is sort of in-your-face), the post is elegantly shown to be on Physics.SE (well, if you know the icon, anyway). The tags are italicized to show that they link to a different site tags, and the &quot;bumping user&quot; (me) has his/her rep on that site shown. We can also add an indicator on the question on site A () that shows that it was soft-migrated. We can use tooltips as well on the icons to tell us why they're here. After all, half of SE documentation is in tooltips.  Now I know that these issues will probably be raised:  Rep: An avid user on Site B gets no Site B rep for giving a good answer on Site A. Frankly, I don't care about this to much, but others may.  Implementation: It may get complicated. Internally, I'd propose that none of the question data is copied, rather Site A pushes the vote/bump data whenever a vote/bump happens. The easiest way to then implement the soft merge would be to have a table of questions soft-merged &quot;to&quot; site B on site B itself, with columns for all the vote/etc data. The questions table should have an extra column for &quot;soft-migrated to&quot;--that way Site A can determine where to push new data to on every vote/bump. Now, all Site B has to do is take the JOIN of the questions table and the soft-merge table and display them in the new questions list (or any list, for that matter). With some extra formatting, maybe. Of course, I may be oversimplifying this and I don't really know what I'm talking about ;-)  Is there a need? : Yes, I would say so. Such questions can get awesome answers is both the communities participate, but our don't-cross-post-much policy deters this. In the end, this will result in better post quality, making the Internet better. Also, as area51 grows, we will see this problem more and more, and this will become more and more necessary.   Thoughts? Any better ideas? Waffles?  Update: Another use case for this would be to soft migrate all MSO  questions over to child metas, effectively solving As shown in various episodes ("Mirror, Mirror," "Phantasms," etc.), other universes exist, oftentimes containing the same characters, albeit in different situations than in the prime universe. I'm curious, though, whether individuals that apparently exist outside of the multiverse, such as members of the Q, would not be duplicated elsewhere. It seems reasonable to me, but I'm not sure. BibTeX loses capitals when creating .bbl file Scheduling a team based activity with 10 different teams and X different games. Every team must meet each other ONCE but never twice, What's the most efficient way to concatenate strings? I was trying to install Linux on my MacBook for class when I bricked my computer, which now in an unbootable state.   I made my partition too small, so I was going to delete and create a larger one. However, Disk Utility did not allow me to delete the small partition. I followed the instructions from   However, not only was I still unable to delete it, but upon restarting I realized my primary partition (located on the same disk) changed into FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF, and I had no options to boot.  (I am sure I performed the command on the correct disk and partition)  I saw some similar threads, but my main bootable drive is the one that got corrupt.   I don't want to lose any data. I'm not the most terminal savvy, so ANY help is appreciated, and I will kindly provide any additional information!  (Disk 0, partition 2 is my main partition, and that only one I care about)  Below are the results of  $ diskutil list and $ gpt -r show disk0.        UPDATE: :  I have followed @klanomath 's instructions. At the last step I received the following error:  Checking prerequisites Checking the partition list Checking for an EFI system partition Checking the EFI system partition's size Checking the EFI system partition's file system Problems were found with the partition map which might prevent booting Error: -69766: The partition map needs to be repaired because there's a problem with the EFI system partition's file system Underlying error: 8: POSIX reports: Exec format error    FINAL UPDATE: SUCCESS!  I just wanted thank @klanomath for helping me through this entire process. He spent 11 hours TeamViewing with me until not only my files were accessible, but until I could access my computer as could before this whole debacle (and this was after 5 hours of email correspondence).   To any future reader with this problem: PLEASE don't give up, it can be fixed! I'm a Georgian national holding a multiple entry Schengen visa.  Last summer I was traveling to Hungary, spent a few days there, then flew to the UK. The Hungarian border official did NOT stamp my passport on exiting the Schengen area. I had to enter it again a few days later and the German border guards were confused by what had happened. Finally they let me enter.  Now I have one more entry stamp into Schengen than exit stamp and run into problems EVERY time at a Schengen border.  Is there a way to fix this? How to copy text out of a PDF without losing formatting? How to change the order of the subcategory and category in a post? I guess it is something simple which I'm not able to see. Any help would be much appreciated. Best, M. How can I decide between the medium sized intuos tablet or the small one? I am a high school student with an interest for drawing tablets for some hobby. I went to check on a store that sell Intuos, a sales representative (or something) of Wacom told me that most students buy the medium sized tablets. Even the staff said that since it is always bought the supplies of the medium size are a lot more than the small size.  I am on a tight budget (which is why I am buying the Intuos), and the small size seems small to me (when my hands are open, my thumb and my pinky would reach the sides). But then, why would Wacom sell the Manga variant in small? Is the staff just saying that so I would buy the more expensive one?  I have enough savings from my small allowance to buy the small size right now, should I wait for another month so that I can buy the medium size? I have read questions about this, and people say that it is just to include the natbib package and the plainnat style. For some reason my references will not sort alphabetically. Any help on this would be much appreciated! I am really new to LaTeX ...  My commands:  \documentclass[a4paper,norsk]{article} \usepackage{amstext} \usepackage{makeidx} \usepackage{graphicx} \usepackage[comma,authoryear]{natbib} \usepackage[norsk]{babel} \usepackage[hmargin=3cm,vmargin=3.5cm]{geometry} \pagestyle{plain}  \begin{document}  \begin{thebibliography}{56}  \end{thebibliography}  \printindex  \bibliographystyle{plainnat}  \end{document} Shape of confidence interval for predicted values in linear regression Galois group of irreducible cubic equation The polynomial $f(x) = x^3 -3x + 1$  is irreducible, and I'm trying to find the splitting field of the polynomial.  We've been given the hint by our lecturer to allow an arbitrary $\alpha$ to be a root and then to check that $\alpha$ is a root, then $2-\alpha^2$ is also root. I've done this with no problem.  My issue is since this is a polynomial of degree $3$, there must be another root that is somehow related to $\alpha$ so that I can create the splitting field and in turn the Galois group of my polynomial but I have no idea what this last root could be. My wife has several files and folders that somehow ended up having filenames that have caused them to be undeleteable (can't be deleted) by normal means or via the command line. I believe the filenames are too long due to the depth of the folder structures. Does anyone know of a good utility for cleaning up files like this? Key Derivation Functions vs. Password Hashing Schemes Key derivation functions, such as HKDF (standardized in ), are meant to stretch some initial keying material having enough entropy, like a Diffie-Hellman shared value, into one or more strong cryptographic secret keys.   Password-hashing schemes, such as the  winner , are meant to hash usually low-entropy passwords with the goal of making the hash digest inversion as costly as possible for an adversary with respect to CPU and memory consumption, as well as parallelization.  Is it exact to consider that password-hashing schemes are actually key derivation functions specialized for low-entropy inputs? Or is there any other essential difference of theoretical nature between these two types of cryptographic schemes? Is there a constructive way to exhibit a basis for $\mathbb{R}^\mathbb{N}$? I have a product key for windows 8.1 (Single language edition or not that i can't remember). I have currently windows 10 pro installed.  I am planning to install windows 10 Home so i activate with windows 8.1 key.  So my question is will i be able to activate it if the Product Key is Windows 8.1 Single Language and i install Windows 10 Home(Multiple language edition) or vice versa. With a two-party system, our nation will divide the people (who/whom)   most need to be brought together.   Do I use who or whom for this sentence?  I think that "people" is the direct object and warrants the use of "whom", but I want to make sure I'm right.