Ubuntu is not booting after grub. I have a black screen
My computer boots to a black screen, what options do I have to fix it?
Is QImage able to open and render pure 16-bit images? Prevent href="#" link from changing the URL hash I am generating one report where I need to use background image. But I found that image always starts leaving some margin space to left side.    \documentclass{article} \usepackage{wallpaper} \usepackage{mdframed} \usepackage[top=2cm, bottom=2cm, outer=0cm, inner=0cm]{geometry} \begin{document}  Some content \ThisLRCornerWallPaper{1.0}{image.jpg} \end{document}    How can I use background image covering whole page? If I write the following class:  public class Example {        int j;       int k;        public Example(int j, int k) {            j = j;            k = k;       }        public static void main(String[] args) {            Example exm = new Example(1,2);            System.out.println(exm.j);            System.out.println(exm.k);       }  }   The program compiles, but when I run the program, the main method will print out two 0s. I know that in order to say that I want to initialize the instance variables in the constructor I have to write:  this.j = j; this.k = k;   But if I don't write it, then which variable is evaluated (or considered) in the constructor (on the left and on the write hand side of the expressions)? Is is the argument or the instance variable? Does it make a difference?  Are there other cases where the use of this is obligatory? How to find and replace in linux on a large file? Oh, hi; So I've got this big json file and I'm trying to find and replace a few things but when I've used sed I get an error and I need a sed or awk string to find and replace it, without getting an error.  prajwal  Current: {&quot;telephone_numbers&quot;:[&quot;1-  Future: {&quot;telephone_numbers&quot;:[&quot;+1-  This is the command i tried and the error i got. sed -i 's/{&quot;telephone_numbers&quot;:[&quot;1-/{&quot;telephone_numbers&quot;:[&quot;+1-/g' output.json sed: -e expression #1, char 56: unterminated `s' command How can I change this method to query my master detail object? I am new to Apex trying to do some practice assignments and have gotten stuck on this junction object query.  Task: Edit the current getUser() method to do the following:  Return a custom object (that you define in the class) with the current getUser method's query data, and the list of teams the person belongs to (by querying the team assignments).   Parent Object 1: User (Standard Object) Parent Object 2: Team (Custom Object) Junction Object: Team Assignments (Custom Object)    **Original Class &amp; getUser Method** global class CTI {     global class CTIException extends Exception {}      global static User getUser() {          return [SELECT Id, Name, ProfileId, Profile.Name, UserRoleId, UserRole.Name, Username                  FROM User WHERE Id = :UserInfo.getUserId() ];     } } How do I detect orientation on app launch for splash screen animation on iPad! How to typeset a file path? Note: $x_n$ is a sequence which is not necessarily convergent.    The following was my attempt. Since $\lim_{n\to \infty}a_n=a$ then $\limsup_{n\to \infty}a_n=a$ . Also $\sup(a_nx_n)=\sup(a_n)\sup(x_n)$. Therefore, $\limsup_{n\to \infty}a_nx_n=\limsup_{n\to \infty}a_n\limsup_{n\to \infty}x_n=a\limsup_{n\to \infty}x_n$.    I am not sure if this is correct. So could someone please show me how it is done. Thanks Update 02/02/2019 I appreciate all the responses and help but unfortunately i must have not seen the emails stating there were responses! I am now looking into a NEST thermostat and was curious if they too, use the same connections. Lastly, looking for a quick recommendation on which WiFi Compatible therms are preferred by the memebers that respond! Thanks again your knowledge is highly appreciated! Bob  I Purchased the Honeywell WiFi Prog Thermostat to replace my Round Digital Honeywell Thermostat. I have separate Heating and Cooling (Heating is a Weil McLain Boiler for Hot water baseboard and Hot water(no tank) and Cooling is a separate unit that was added later.)  Wires:  RC Cool R Heat W Heat Y Cool G Cool   3 wires from AC unit and 2 from Heater.  If I were to go the separate transformer route to power the thermostat, where would I land the 2 wires?  C and ??? Why is the ##UserID## parameter not populated in Data Explorer anymore? Environment I'm logging in using the OpenID from  and using Chrome 31.0.1650.57 m if that matters. Steps to reproduce: Log in to  and , for example, like: DECLARE @MyUserID INT = ##UserID:int##  SELECT TOP 1     Id AS [Post Link],     Score AS [Score],     CreationDate AS [Creation Date] FROM     Posts WHERE     OwnerUserId = @MyUserID AND     PostTypeId IN (2, 3) ORDER BY     CreationDate DESC  Then press the Run Query button and see if the UserID field is filled with your own user ID like shown in the below screenshot:  Question: Did something changed on the ##UserID## parameter (for example, that it's not supported anymore)?  If so, then there is an outdated  paragraph about it (What's the point of logging in). If not, it is a bug which is there about three days (I've been waiting since I noticed that you were going to do some changes to Data Explorer, but it remains there, hence my question). How do I use regular expressions in bash scripts? I want to check if a variable has a valid year using a regular expression. Reading the  I understand I could use the operator =~  Looking at the example below, I would expect to see "not OK" but I see "OK". What am I doing wrong?  i="test" if [ $i=~"200[78]" ] then   echo "OK" else   echo "not OK" fi This is probably pretty basic, but to save me an hour or so of grief can anyone tell me how you can work out the number of bits required to represent a given positive integer in Java?  e.g. I get a decimal 11, (1011). I need to get the answer, 4.  I figured if I could work out how to set all the bits other than the most significant bit to 0, and then >>> it, I'd get my answer. But... I can't. Does tourist visa (90 days) apply after a long-term visa ends in Schengen countries? I am an Australian currently on a Netherlands working holiday visa that ends in May next year. I would like to know if when my visa ends I then get another 90 days just as a regular tourist visa as I would like to do some more travel within Europe when my visa ends before going home to Australia. Significance of $\sqrt[n]{a^n} $?! There is a formula given in my module:  $$ \sqrt[n]{a^n} = \begin{cases}  \, a  &amp;\text{ if $n$ is odd } \\  |a| &amp;\text{ if $n$ is even } \end{cases} $$  I don't really understand the differences between them, kindly explain with an example. I understand that the expressions on both sides of an equal sign are the same entity, and I know that when you modify one side, the other must be changed because it is referring to the same thing. What I do not understand is why making a new equation (adding or taking away from an expression) allows one to know what an unknown represents. What about equations lets us do this? Do "Best by: XX-XX-XX" foods have an expiration date? How long will foods that have "Best by: XX-XX-XX" on the product last past that date?  I have tried looking online, and all I can find is anecdotal evidence, which isn't very assuring for me since there seems to be no specific "x food will expire y weeks after its best by date".  Is there a rule of thumb or some guide out there that can tell me how long a "best by" food will last? Or is it safe to assume that they never expire, since it's not actually labelled on the product? How do I start applications automatically on login? I think this is a very recent design change, because I've not seen it before:    Where before a small box with the bounty value dislocated the title a couple of characters to the right, now the additional text saying how long until it expires dislocates the title by about a quarter of the width of the column.  I find that this makes it much harder to read the title, and is counterproductive to the goal of attracting attention. Edit Mail rules manually