I recently updated to 13.10 and it broke all my opencv stuff (impossible to compile or run previous programs that were ok on 13.04).  Cuda wasn't installed anymore, nor were the nvidia drivers.  So I tried to install them again (did it in 13.04). I tried all the suggestions here:  That is, trying to install from:   sudo ./NVIDIA-Linux-x86_64-331.20.run   It didn't work but I could recover from the low graphics mode issue. After enabling the proper repository I tried:  sudo apt-get install nvidia-331   It didn't work either. Finally   sudo apt-get install nvidia-current-updates-dev   This got me totally stuck; I now can't get out of low-graphic mode.   I've checked and tried:      What else can I try?
Note: This is an attempt to create a canonical question that covers all instances of &quot;low-graphics mode&quot; error that occurs to a user, including but not limited to installation of wrong drivers, incorrect or invalid lightdm greeters, low disk space, incorrect installation of graphics card like ATI and Nvidia, incorrect configuration of xorg.conf file while setting up multiple monitors among others. If you are experiencing the &quot;low-graphics mode&quot; error when trying to login but none of the following answers work for you, please do ask a new question and then update the answers of this canonical question as and when your new question gets answered.   When I try to boot into my computer, I am getting this error:  The system is running in low-graphics mode Your screen, graphics cards, and input device settings could not be detected correctly. You will need to configure these yourself.   How do I fix the failsafe X mode and login into my computer?  Answer index:
Which comes first: cat or dog? Which comes first in a sentence?  I know some word pairs such as bacon and eggs, where bacon always comes first. E.g:     Make me bacon and eggs for dinner, honey.   Cats and dogs are the two most common pets I know of. What is the preferred order?   Dogs are superior.     Don't put dogs and cats together, they might fight!  Cats are superior.     Don't put cats and dogs together, they might fight! Unable to locate package lib32bz2-1.0 I am trying to install Simplicity studio on Ubuntu 15.04 (64-bit) and I get this error  E: Unable to locate package lib32bz2-1.0 E: Couldn't find any package by regex 'lib32bz2-1.0'   I tried to install lib32bz2-1.0 package, again I get the same error. How to install package lib32bz2-1.0 on Ubuntu 15.04(64-bit) How to use host names rather than ip addresses on home network? I've a small home network up and running and managed to set up ssh. Can anyone tell me what I need to do to refer to one computer on the network from another by host name rather than IP address (which is what I'm doing now)? Drag-and-drop functionality no longer working after upgrade to 19.04 After upgrading from 18.04 to 19.04 (with a necessary upgrade to 18.10 between) on a Lenovo Yoga 11e, I can no longer drag and drop anything (ie, files, windows, etc.) with the touchpad.  I can, however, move things around using the touchscreen.  Whenever I attempt to do so with the mouse, though, sometimes it turns into a hand.  Whether or not it turns into the hand or remains a pointer, the icon will not move anymore.  IOW, as soon as I left-click, the pointer freezes in place until I release the touchpad. What are some uses of template template parameters? I've seen some examples of C++ using template template parameters (that is templates which take templates as parameters) to do policy-based class design. What other uses does this technique have? How can I make a time delay in Python? I would like to know how to put a time delay in a Python script. My multimeter is rated to 600V.  How can I readily (and safely) use it to measure higher voltages? Can helium disappear from Earth? Helium is lighter than air, so it should fly off from Earth. Is it possible that in the future we will run out helium? Permanent Redirect (WWW to non WWW) Can anyone tell me the name of these sentences? zsh scripting - How do I NOT match a pattern in filename generation? I'm currently trying to loop through a set of directories, but only the ones I care about.   $ ls -d */ cfdpost_statefiles/     p050L0260/  p050L0510/  p060L0390/  p070L0260/  p070L0510/  p092L0390/  p097L0260/  p110L0390/  p131L0325/  p150L0510/  profiles/ ERCOFTAC_TestSettings/  p050L0390/  p060L0260/  p060L0510/  p070L0390/  p084L0510/  p094L0325/  p100L0510/  p125L0510/  p136L0260/  p162L0260/  settings/   I want to match all the p###* directories except for the ones beginning with p125 and p150.  If I just do patterns with a pipe, I get:  $ for dir in ./p(125|150)*(/); echo $dir ./p125L0510 ./p150L0510   However, if I try and use the ^ like it shows :  $ for dir in ./p^(125|150)*(/); echo $dir zsh: no matches found: ./p^(125|150)*(/)   Any ideas how to proceed? How do I get a really wide tilde?  I need to cover at least  abcdefghijklmnopqrstuvwxyz  The \widetilde command does not work. Nor using \stackrel with \sim. In Ubuntu 18.04 I'm not able to assign Ctrl+Alt+← or Ctrl+Alt+→ to anything. To be precise I may bind it to something, but it doesn't work when using the keyboard combination, up/down arrows do however work.   .  The strange thing is that the system detects the keyboard combinations when assigning a key, but not when trying to use them. As a result the keyboard combinations don't work in any other programs either. In the Phone app (iPhone 5, iOS 6.1.2), I click on a contact's number, the call is initiated and starts ringing.   For a brief moment at this point, the label of the number (home / work / etc…) is displayed alongside the contact's name, but it quickly is removed and replaced with the call timer counting up and only the name (and picture of the contact) are shown.      How can I see the number that is being called during a phone call? Linux Bulk/Remote Administration Beside our internal IT infrastructure, we've got around 500 Linux machines hosting our services for the on-line world. They are grouped in a bunch of clusters like Database A-n, Product A-n, NFS, Backoffice and so on. Furthermore, they are administered by an external provider, according to our specifications and requirements.  However, we face a lot of trouble during (web-) software development, roll-out and deploy - especially because the dev- and staging-environments have almost nothing in common with the live systems (I spare out the nasty details..).  Thus, I've tried to create virtual machines, copied the various live-systems as exactly as possible and prepared them to connect to e.g. the development-databases instead of the "real" ones transparently for developers (they aren't root). This works pretty well, but...  I was wondering how one could administer those systems remotely and in bulk? Is there some software family I'm not aware of? Or, at least, some techniques or principles one should be familiar with?  We would provide every developer with a bunch of images to be run locally (VirtualBox). The QA dept. would get virtual clusters (XEN or Hyper-V). If I need to provide an additional server-module, re-route a new database connection or just want to update everything provided by the package manager... how could I possibly do that without being forced to log on to every system and/or ask my colleagues to download and run some fixture-script?  I believe there are plenty of solutions. Well, somehow I'm too stupid to enter the correct keywords into the search engines... Or isn't this issue as trivial as it sounds?  For the record:   Almost all systems are running Debian GNU/Linux 6.x "squeeze" No developer is forced to use a particular OS at his/her workstation The budget is limited, of course, but not too small to buy proprietary software A solution that would involve our aforementioned provider is preferred I have 3 folders with large amount of data in each which has to be maintained seperately. Can I create a sym link or shortcut.in windows which should show me the merged contents of the 3 folders. I am not looking for library conf in Win7.   Any suggestion is highly appreciated. How do I interpret the Mann-Whitney U when using R's formula interface Javascript replace all "%20" with a space What makes matter travel along geodesics? Identifying genes from a list of genes I have a gene list file. Some thing like this      SWT21     SSA1     NRP1     EFB1     TFC3     MDM10   I have another file which also contains the names of these genes in my list along with other essential information about them. The second file looks like this:  chrI    147593  151166  YAL001C -   TFC3 chrI    143706  147531  YAL002W +   VPS8 chrI    142173  143160  YAL003W +   EFB1 chrI    140759  141407  YAL004W +   YAL004W chrI    139502  141431  YAL005C -   SSA1 chrI    137697  138345  YAL007C -   ERP2 chrI    136913  137510  YAL008W +   FUN14 chrI    135853  136633  YAL009W +   SPO7 chrI    134183  135665  YAL010C -   MDM10   I want to extract those lines in the 2nd file which have gene names as are present in first file.