Can't undo upvote on comments. The comments area understandably has a small interface and I accidentally upvoted the wrong comment. Apparently they cannot be un-upvoted.
As mentioned on :     For something that can be done so   easily by accident, there should be   the ability to undo mistakes.   I know that I have clicked several times on a comment up-vote without actually wanting to.  I would suggest being able to cancel the up-vote (maybe only for a couple of minutes or even less than a minute, no problem, as long as I can undo a miss-click).
I have recently upgraded my OS to Ubuntu 18.04 (fresh install via boot device). However, when trying the command:  sudo apt-get upgrade   It works fine until ~75% when it stops and says:  snapd.snap-repair.service is a disabled or a static unit, not starting it.   I'm not quite sure what this means and if I Crtl-Z to get out of it, any time I try to install anything I get:  E: Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable) E: Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?   and have to restart my computer to install anything. Why the rows returns by "explain" is not equal to count()? Why don't all Jedi stick around as force ghosts? In many of the Star Wars movies, Jedi come back as Force ghosts.    Why don't they stick around forever, giving advice to new generations, as well as countless knowledge from thousands of years? Blender 2.8 - AWS EC2 command line EEVEE render I have been trying to get this to work for a couple days now. I have an EC2 P2 instance with NVIDIA CUDA configured by default, its a Deep learning Ubuntu AMI. This OS does not have a GUI so everything is via terminal.  I downloaded Blender's 2.8 TAR file for Linux and set it up on the EC2 instance. And ran the following command from the directory where the TAR file is extracted:   ./blender -b -noaudio /home/ubuntu/file.blend --render-output . --engine BLENDER_EEVEE --render-format PNG --verbose 4   All I see in the output is this:  Blender 2.80 (sub 75) (hash f6cb5f54494e built 2019-07-29 17:17:04) found bundled python: /mnt/blender/blender-2.80-linux-glibc217-  x86_64/2.80/python Read blend: /home/ubuntu/file.blend  Blender quit   Don't know why its quitting but I am unable to debug this any further. Any help would be appreciated.  UPDATE: As per @rjg's recommendation, ran the following command:  ./blender -b -noaudio /home/ubuntu/file.blend --render-output . --engine BLENDER_EEVEE --render-format PNG -f 1 --verbose 4   Got the following error:  Blender 2.80 (sub 75) (hash f6cb5f54494e built 2019-07-29 17:17:04) found bundled python: /home/ubuntu/blender/blender-2.80-linux-glibc217-  x86_64/2.80/python Read blend: /home/ubuntu/file.blend Unable to open a display Aborted (core dumped) Future Simple and Future Perfect I've read  about Future Simple and Future Perfect, but I still can't understand the exact usage of these two tenses. Is there any diffrence between the following?     I will do my homework by 6 p.m.   I will have done my homework by 6 p.m.       I will do my homework after school   I will have done my homework after school   Also, I've checked the word 'by' in  and there're some confusing examples:       By the time (that) this letter reaches you I will have left the country.   Can I use 'By the time (that) this letter reaches you I will leave the country' instead? Array only adds duplicate values Geocoding USA addresses that cannot be sent over internet? For a one-time project, I need to geocode a few thousand addresses.  In the past I've used various online resources for this kind of thing (e.g., Google Maps API), but the addresses I'm working with have to be kept confidential - which means no sending it over the Internet, unless there's some iron-clad guarantee of privacy.  What other options do I have? Skins that cannot be in mystery gifts? Yesterday I had a discussion with some of my friends while playing league. It was about the contents of the mystery gifts and while I said there are restrictions, they were convinced that you can get absolutely every skin from a gift (including victorious, and really old ones).  Now while I'm pretty sure that there are restrictions (Triumphant ryze for example), I'm not really sure on which skins they affect.   What about the victorious, riot, legacy, pax and completely removed skins (Rusty BC, Black Ali, Urf WW)? Can you get those with a mistery gift or is it impossible to get those right now? Want to delay startup of program but can't find it in Task Scheduler I'm trying to delay the startup of a specific program that loads at login. As per an answer in , I should be able to do it using Task Scheduler. The problem is, I can't find the program listed anywhere. Is there a particular pane I should be looking in? The program is Razer Synapse so I don't think it would be in the Microsoft or Western Digital folders.    If it's not in Task Scheduler, is there another way I can delay it at startup?  Out of curiosity how many ways are there for a program to be run at Startup in Windows? How to prevent SIGPIPEs (or handle them properly) Ideal contained in a finite union of prime ideals Let $I \subset R$ be an ideal and $P_i$  $(i=\{1,...,n\})$ prime ideals with $I\subseteq\bigcup_{i=1}^nP_i$. Prove that then $I$ is contained in one $P_i$.   I don't know how to show this because I don't have any approach.  So I am looking for something to start with or something like a sequence of tips (Since I know this is a large proof)  Thanks in advance! I realize this is probably going to come off as a bit silly, but in Iron Man II how could James Rhodes easily don the Mark II armor that was designed to fit Tony Stark?  As you can see in this image (which isn't an "in universe" shot) Tony and Rhodey are roughly the same height, but it appears that Rhodey has a smaller frame than Tony, which would seem to make for an ill fit of the armor, especially for flight.  This issue could of course have been addressed by the Air Force during the retrofit with Justin Hammer. 16.04 new installation gives grub-efi-amd64-signed failed installation /target/ ubuntu 16.04 at the end I am installing Ubuntu 16.04 in an Intel NUC computer with UEFI enabled. I am using an SSD from another computer. During the installation I chose Erase the disk and make a new full install  At the end of the process I see:  grub-efi-amd64-signed failed installation /target/ Ubuntu 16.04    And the system does not boot.  I tried to use boot-repair but apparently it does not solve the problem. Do creatures that enter the battlefield at the same time see each other enter? iPhone makes shutter sound when taking photos despite being on mute Poiseuille's law states that the rate of flow of water is proportionate to $r^4$ where $r$ is the radius of the pipe. I don't see why.  Intuitively I would expect rate of flow of fluid to vary with $r^2$ as the volume of a cylinder varies with $r^2$ for a constant length. The volume that flows past a point is equal to rate of flow fluid, and thus it should vary with $r^2$.  I cannot understand the mathematical proof completely. Is there an intuitive explanation for this? I'm using Ubuntu 14.04 but since some weeks I'm stuck with the old 13.10 lockscreen design for some reason.  I already tried compizconfig-settings-manager but it doesn't offer me any option for changing the lockscreen design and even resetting Compiz and Unity with   dconf reset -f /org/compiz/   didn't help.  Are there any other ways to get the new lockscreen back? Visual Studio - How to change the return value of a method in the debugger? When I'm debugging, I often have to deal with methods that does not use an intermediate variable to store the return value :     private int myMethod_1()    {       return 12;    }     private int myMethod_2()    {       return someCall( someValue );    }   Well, in order to recreate a bug, I often have to change values on the fly. Here, I could want to see what happens when myMethode_1 return zero. Same thing for myMethod_2.  Is there a way to do that without modifying the code ? What I would like to do, it's to place a breakpoint on the return line (or on the closing bracket) and type-in a new return value.  Note : I'm using Visual Studio 2005 and Visual Studio 2008.  Thank ! Using Either a Comma or a Semicolon My teacher was explaining how sometimes a comma isn't enough to make a sentence correct, and that sometimes you have to use a semicolon. I am having trouble figuring out when you should use which.   Can someone please explain? If Anakin Skywalker didn't get what he wanted as a Sith (to save Padmé), why was he still a Sith? In the prequels, the primary reason Anakin was willing to become  is because he wanted to save Padmé;     ANAKIN: I will do whatever you ask.       PALPATINE: Good.       ANAKIN: Just help me save Padme's life. I can't live without her. If she dies, I don't know what I will do.      PALPATINE: To cheat death is a power only one has achieved, but if we work together, I know we can discover the secret.       ANAKIN kneels before PALPATINE.       ANAKIN: I pledge myself to your teachings. To the ways of the Sith.   Given that he didn't manage to save her, why did he still become a Sith?