I accidentally used sudo rm * while I was in the root directory. Now, I am not able to open terminal and my computer does not shut down, only a single _ is flicking on the black screen. How can I solve this/reset my computer?
I stupidly ran sudo rm /* followed by sudo rm -R /*  My sites still run, although the vast majority of commands like ls are now broken.  Is there a simple way to get data off the server or reverse some of damage?
Summation by parts (finite calculus) of $\sum\limits_{i=0}^{n}i\cdot a^i$ I'm studying the calculus of finite differences and have read about summation by parts:  $\sum f(x)\Delta g(x) = f(x)g(x) - \sum g(x+h)\Delta f(x)$.  The tutorials I'm using go a bit woolly at the point of introducing this technique: they use examples where they set $\Delta g(x)$ to $2^x$, and don't really show how to use it for anything a bit harder. I'm at a loss for basic examples.  I wondered if it is possible to determine  $S.n = \sum\limits_{i=0}^{n}i\cdot a^i$  using summation by parts?  If so, how is it done?  Thanks in advance. Exam with 18pt main font Remove automatically added keyboard inputs and prevent them from coming back (Windows 10) I have 2 languages installed on my computer, both with a single input method.  I have 2 keyboards: CES-CSQ and ENG-US.    However lately (maybe after the last Win10 update) I started to see 2 additional keyboards in my systray  - namely CES-CS and ENG-CSQ.    Is there there a way to remove those 2 input options (CES-CS, ENG-CSQ) which I do not see in the Control panel's Language options?  Solution described at  question does not apply to my problem because I do not see input options that I want remove in Control panel's Language options. A calculus problem with functions such that $f''(x) = g(x)$ and $g''(x) = f(x)$ What did Bill do to make Hanzo mad? During kill Bill, we learn that all the black mamba had to do to get Hanzo to build her a sword, was to mention Bill's name.  When black mamba meets Bill at the end, she tells him that all she did was mention his name. Bill responds with, "that'll do it!"  So what was it that Bill did to Hanzo to make him come out of retirement and make another weapon of death? List has no rows for assignment to SObject In popular science books and articles, I keep running into the claim that the total energy of the Universe is zero, "because the positive energy of matter is cancelled out by the negative energy of the gravitational field".  But I can't find anything concrete to substantiate this claim. As a first check, I did a calculation to compute the gravitational potential energy of a sphere of uniform density of radius $R$ using Newton's Laws and threw in $E=mc^2$ for energy of the sphere, and it was by no means obvious that the answer is zero!  So, my questions:   What is the basis for the claim &ndash; does one require General Relativity, or can one get it from Newtonian gravity? What conditions do you require in the model, in order for this to work? Could someone please refer me to a good paper about this? Will my Chinese visa still be valid if I renew my passport? Will my Chinese visa still be valid if I renew my passport? If so how does that work?  I have heard that you can travel with your new passport and just show the old passport with the valid visa when entering China. Has anyone done that? Recently?   I have also been told that you have to get a new visa, which seems somewhat logical but frustrating, especially when my Chinese visa is only a few months old.  My Chinese visa was issued in late Nov 2014 and I heard the rules changed between the US and China. My visa says it's good for 10 years and my US passport expires in 5. Lost passport with Schengen visa My passport was stolen in Prague on my way to Vienna. I filed a police report and our embassy swiftly acted by giving me a temporary passport for my onward journey to Munich and Rome. Upon exit from Rome, the immigration ask for the Schengen visa, when I told him that I lost my passport, he did not ask for any document to support my claim, he just stamped my new passport with exit. I am not sure if on record, I am officially out of the Schengen area or not. I am scared that without the lost visa, it appears that I am still in the area and might reach the 90 day limit and will be denied when I re-apply as it would appear I broke the rule. What to do? How can I add a bookmark in my nautilus folder explorer In Ubuntu 11 I just dragged the folder there.  This seems to be not possible on my new Samsung ultrabook with Ubuntu 12.04   I've tried Ctrl+D and using the top menu but nothing happens and no error messages, just nothing.  How can I add a bookmark? How do I make my own horse follow me? I've found a horse in Skryim and I ride it a bit to explore the wild but when I dismount, it wanders away and doesn't stay where I leave it. How do I stop it from doing this? Is there a special thing I forgot about horses? I didn't steal this horse - it was from an Imperial Fort that I've cleared. a function or a factor to scale a list of real numbers from one range to another Reprojected MODIS NDVI has range from -32768 to 32767, expected -1 to 1 My PS3 controllers have died and are not charging What is the best way to restrict access to adult content? I bought my kids a PC and installed 12.04 (Unity) on it.  The bottom line is, I want my children to use the computer unsupervised while I have confidence they cannot access anything inappropriate.  What I have looked at:  I was looking at Scrubit a tool which allows me configure my wifi router to block content and this solution would also protect my other PC and mobile devices.  This may be overkill as I just want the solution to work on one PC.    I also did some Google searches and came across the application called .  My experience of OSS is that the best solutions frequently never appear first on a Google search list and in this case I need to trust the methods therefore my question is very specific.   I want to leverage your knowledge and experience to understand What is the best way to restrict adult content on 12.04 LTS as this is important to me.  It maybe a combination of things so please don't answer this question "try this or that", then give me some PPA unless you can share your experience of how good it is and of course if there are any constraints. How can I repair grub? (How to get Ubuntu back after installing Windows?) In Java, are there clear rules on when to use each of access modifiers, namely the default (package private), public, protected and private, while making class and interface and dealing with inheritance? Create a variable in .CSS file for use within that .CSS file Possible Duplicate:          We have some "theme colors" that are reused in our CSS sheet.  Is there a way to set a variable and then reuse it?  E.g.  .css OurColor: Blue  H1 {   color:OurColor; } How do I concatenate JavaScript files into one file? e.force:navigateToURL: [Cannot read property 'setParams' of undefined]