While is was installing something with the sudo apt-get install command I accidentally accepted the command   sudo apt-get install python3-   (yeah I know it is stupid to just accept this but I did a lot of those and i just continued to click y).  By executing the command I deleted my whole visual desktop of Ubuntu (I just had the plain shell but I recovered the visual desktop by now). I don't know if I am just stupid but nevertheless I want to create awareness that you shouldn't use the command.  If you can explain to me why happened what happened feel free to explain it to me.
I was looking for some package (nautilus-terminal), and accidentally did this:  $ sudo apt-get install nautilus- Reading package lists... Done                                                                                                                                                                                                  Building dependency tree                                                                                                                                                                                                       Reading state information... Done                                                                                                                                                                                              The following packages were automatically installed and are no longer required:                                                                                                                                                  apturl apturl-common libgail-3-0 linux-headers-4.4.0-57 linux-headers-4.4.0-57-generic linux-image-4.4.0-57-generic linux-image-extra-4.4.0-57-generic                                                                       Use 'sudo apt autoremove' to remove them.                                                                                                                                                                                      The following packages will be REMOVED:                                                                                                                                                                                          gnome-session-flashback nautilus nautilus-sendto nautilus-share ubuntu-desktop                                                                                                                                               0 upgraded, 0 newly installed, 5 to remove and 69 not upgraded.                                                                                                                                                                After this operation, 2 031 kB disk space will be freed.                                                                                                                                                                       Do you want to continue? [Y/n] ^[[^C                                                                                                                                                                                             That's quite dangerous because remove is much harder to mistype than a simple dash from a failed autocompletion.     Is that an equivalent of apt-get remove? I couldn't find any documentation for that. Edit: except for overlooking the man page...
Show that $K[x,xy,xy^2,\dots]$ is not Noetherian Here is the problem I am stuck on: Fix a field $K$ and consider the subring $A \leq K[x,y]$ generated by $K \cup \{x,xy,\dots,\}$. Show that $A$ is not Noetherian.  I figure that taking ideals $I_n = (x,xy,\dots,xy^n)$ should give an infinite strictly ascending chain, which would establish that $A$ is not Noetherian, but I cannot figure out how to show that each $I_n$ is a proper subset of $I_{n+1}$. Any help here? What is the difference between the GNU Makefile variable assignments =, ?=, := and +=? Can anybody give a clear explanation of how variable assignment really works in Makefiles.   What is the difference between :   VARIABLE = value  VARIABLE ?= value  VARIABLE := value  VARIABLE += value   I have read the  in GNU Make's manual, but it still doesn't make sense to me. Primary decomposition of a monomial ideal After update, get "error: file not found." followed by "grub rescue> _" Find the infinite sum of the series $\sum_{n=1}^\infty \frac{1}{n^2 +1}$ Show that there is $\xi$ s.t. $f(\xi)=f\left(\xi+\frac{1}{n}\right)$ Let $f:[0,1]\to\mathbb{R}$ be continuous and $f(0)=f(1)$. Show that for any integer $n\geqslant 2$, there is $\xi\in(0,1)$ s.t.$f(\xi)=f\left(\xi+\frac{1}{n}\right).$  I think this requires the intermediate value theorem somewhere. If $\mathfrak p \subset R$ is a prime ideal, prove that for every nilpotent $r \in R$ it follows that $r \in \mathfrak p$.   The only hint that my tutor gave me was to use induction. Can someone explain what he means by this?  Thanks for the help! I have a dual boot laptop (Windows 10). I ran general updates and now my Ubuntu won't boot.   I ran in recovery mode and still it freezes in the same place.      Kernel panic – not syncing: Attempted to kill init! exit code=0x00007f00 Why don't we add a question with the same tag on multiple Stack Exchange sites? Java: how to parse double from regex 12.04 GPU lockup I was able to install Ubuntu 12.04 using the alternative version of the image, (64 bit) but when I start the system it tells me the GPU  locked up, and instead presents a text only screen.  I understand that this site is not for bug reports, but at the same time, I know that there are some versions of the installer than have to be compatible with my graphics card (Nvidia GTS 360M).  I assumed that the mere fact that the alternative installer ran was an indication that I could get some sort of graphical interface running after the install.  Is there some way of getting some type of graphical interface running on my machine? Even better would be is there a way to get the rest of the system running as normal (i.e. GPU up and running)?  If an internet connection is required to download driver support or something similar, directions for how to configure a wireless connection with WPA2-Personal protection from the text-only interface (bash).  Any help would be appreciated.  Note: I was able to find  which tells me that the card is supported.  Note 2: In the install software stage of the install, I was unable to install anything (no internet connection)  Update: The exact error message is [8.591394] [drm] 0000:01:00.0: GPU Lockup - switching to software fbcon  Update 2: If I try to install with the regular version of Ubuntu, the screen goes staticy. This also happens if I install with Wubi (distasteful I know) and then try to use Ubuntu.  Update 3: I've tried xforcevesa, nomodeset and xforcevesa nomodeset as my wubi boot options.  Update 4: Thanks to jokerdino, I can now connect to the internet, so internet tools would now be a possibility. Where can I find a list of Magic Items by rarity? I am currently looking for a list of Magic Items (non-homebrew and preferably Armor/Weapons) arranged in Common, Uncommon, Rare, Very Rare, and Legendary. There is not one in the Players Handbook or Dungeon Masters Guide that is appropriate.  Does such a list exist and if so, where can I find it? trim is not part of the standard c/c++ library? Is it me or are there no standard trim functions in the c or c++ library? is there any single function that acts as a trim? If not can anyone tell me Why trim is not part of the standard library? (i know trim is in boost)  My trim code is  std::string trim(const std::string &amp;str) {     size_t s = str.find_first_not_of(" \n\r\t");     size_t e = str.find_last_not_of (" \n\r\t");      if(( string::npos == s) || ( string::npos == e))         return "";     else         return str.substr(s, e-s+1); }   test: cout &lt;&lt; trim("  \n\r\r\n \r\n text here\nwith return   \n\r\r\n \r\n "); -edit- i mostly wanted to know why it wasnt in the standard library, BobbyShaftoe answer is great. Cannot log into Area 51 with OpenID I recently tried many times to log into Area 51 with my Stack Exchange OpenID. Each time, I got this:    Then, I went to my OpenID account, and I saw this:    ...what is going on??  I have chrome, and extensions that block 3rd party cookies... is that the problem? How does the twitter bot work? The use of "exact same" Cardinality of a set A is strictly less than the cardinality of the power set of A In Elias Stein and Rami Shakarchi's Complex Analysis textbook, we have the following exercise:     Show that if $\{a_n\}_{n=0}^\infty$ is a sequence of complex numbers such that $$\lim_{n\to\infty}\frac{|a_{n+1}|}{|a_n|}=L,$$ then $$\lim_{n\to\infty}|a_n|^{1/n}=L.$$    I've been trying to prove this with no luck. The only thing I've thought of doing is $$\lim_{n\to\infty}\left(\frac{|a_{n+1}|^n}{|a_n|^n}\right)^{1/n},$$but this hasn't lead me anywhere except dead ends. Will someone provide a hint for me about how to proceed? Thanks!  Minor update: I don't know if it's helpful yet, but I know we can write the limit as $$\lim_{n\to\infty}\left(\frac{|a_{n+1}a_n\cdots a_0|}{|a_n\cdots a_0|}\cdot\frac{1}{|a_n|}\right).$$This reminds me a lot of the geometric mean, which even has the exponents I'm trying to get... Why is the direction of cross products of two vectors perpendicular to the plane? Why is the direction of cross products of two vectors perpendicular to the plane? How is that possible? Creating non-reverse-engineerable Java programs