How to install Ubuntu on Dell?
How do I install Ubuntu?
How to change Gnome-Terminal title? I have several instances of terminals running in my working environment, what I would like is to set a specific title for each one, in order to have a clear idea what purpose the specific terminal serves i.e. Apache, editing_ini, postgres etc...  Of course from the command line. Given any $10$ consecutive positive  integers , does there exist one integer which is relatively prime to the product of the rest ? So basically in SQL Server a NULL means there is no value and thus can't be compared which returns some unexpected results.  For example, the following query doesn't return rows where value IS NULL but I want it to:  SELECT * FROM table WHERE   (value != 26)   AND date IS NULL   AND last_modified &gt;= '5/21/2014'   I understand I can do the following as a workaround but seriously? Having to add parentheses and check if is null for every single field every single time I want to include it? Seems ugly, not intuitive and crazy.  SELECT * FROM table WHERE   (value != 26 OR value is null)   AND date IS NULL   AND last_modified &gt;= '5/21/2014'   I mean I know NULL is not a value and thus can't be compared but can't you infer that it is, in fact, definitely not 26? If 26 is something and NULL is nothing and nothing is not something then NULL is not 26. Seems logical to me.  Does anyone know how I can, in a cleaner way, include nulls in my results when using comparisons without having to include an explicit check each and every time. Also turning off nulls on my tables is definitely not an option.  Edit:  My real problem of why I don't want to do it the way I showed was not exposed. So here goes. I am writing a program that let's you build queries to database tables and let's the user dynamically create filters and such which essentially at the end of the day constructs a SQL statement and gets the results to display to the user. The fields chosen by the user can be any and/or all fields in a given database and if I have to literally put that ISNULL check on every single field that would be really inefficient and make looking at the SQL super ugly. My program is table-definition-agnostic meaning I don't care what's in your table and don't want to know what your table's definition is. I just want you to pick a table, choose some fields to filter on with equals, not equals, in, not in, etc ... and then click a button to view the results of that request. "Belongs on" comments I'm really new in using biblatex, compile the sample placed in , but what I get is    1.1 Foo    Some text [B02x ].    1.2 Bar    Some text [B02y ].   Do not get the bibliography by chapters, or the global references.  Really not remains to be done   \documentclass{report}  \usepackage[style=alphabetic]{biblatex}  \addbibresource{references.bib}  \begin{document}  \chapter{First chapter}  \section{Foo}  Some text \cite{childs_temperature}.  \printbibliography  \chapter{Second chapter}  \section{Bar}  Some text \cite{hashemian}.  \printbibliography  \newpage  \printbibliography  \end{document}   And the references.bib    @BOOK{childs_temperature,   title = {Practical Temperature Measurement},   publisher = {Butterworth - Heinemann},   year = {2001},   author = {Childs, Peter R N},   address = {Great Britain},   edition = {1},   isbn = {0 7506 5080 X}   }    @PHDTHESIS{hashemian,   author = {Hashemian, Hashem Mehrdad},   title = {Measurements of dynamic temperatures and pressures in nuclear power plants},   school = {{The University of Western Ontario}},   year = {2011},   type = {PhD {T}hesis}   }   I need to obtain references by chapter and global cited references, but i don't know how compile. Questions with no close votes appearing in the close vote queue? I've just been offered the wonderful opportunity to review .        ... but on closer inspection ?        Is this  (e.g I'm assuming this post did previous have a close vote, but has now aged away in ways I don't understand), or should questions with no active close votes be removed from the queue.  p.s. If it's , please expect my  asking for this not to be the case ;). Integrate : $\int \frac{x^2}{(x\cos x -\sin x)(x\sin x +\cos x)}dx$ $$\int \frac{x^2}{(x\cos x -\sin x)(x\sin x +\cos x)}\ dx$$   My approach :   Dividing the denominator by $\cos^2x$ we get $\dfrac{x^2\sec^2x }{(x -\tan x)(x\tan x +1)}$ then  $$\int \frac{x^2\sec^2x}{x^2\tan x -x\tan^2x+x-\tan x}\ dx=\int \frac{x^2(1+\tan^2x)}{x^2\tan x -x\tan^2x+x-\tan x}dx$$  But I am not getting any relation between numerator and denominator so that I will take any substitution and solve further please suggest whether it is correct and how to proceed in this. Thanks. I obtained a licence key for Windows 8 through DreamSpark. Is there a way to download a Windows 8 ISO image like you could for Windows 7? I am on a non-Windows machine, so I cannot use the Secure Download Manager to download Windows 8 directly using DreamSpark. When a ball is tossed straight up, does it experience momentary equilibrium at top of its path? This question has been asked many times all over the Internet and answers can be found on places such as yahoo and ask.com, but I'm not satisfied with those answers and I don't trust the validity of those places.  This seems like a more appropriate place to ask.  So, here's my train of thought and I would like to ask you if you think I'm right or wrong.  Even though most of the answers point to the fact that the ball does not achieve equilibrium because the force of gravity is constantly acting upon it, thus causing an acceleration, I still think there's a moment of equilibrium and here's why:  When the ball is traveling up, it's accelerating towards the ground and eventually reaches a point at which its speed reaches 0.  At this moment, isn't the reason the speed is 0 is due to the fact that net force is 0?  The force that made the ball travel in the upward direction was canceled out by the gravitational force.  So, the sum of forces at that brief moment is equal to 0, otherwise the ball would be moving.  I don't think gravity is the only force acting on the ball at that moment, since the throwing force was acting on it as well, until both canceled each other out for that brief moment.  Am I right or wrong? Finder search doesn't work properly after Yosemite update Ever since I upgraded to Yosemite, search no longer works properly in Finder. Spotlight works fine but Finder search just gives me a blank window with a spinning ball.  I've tried reindexing and I've also tried deleting Spotlight's .plist file. I restart my MacBook Pro after doing either. Finder search will work for one or two queries and stop again. I don't know what else I can do. Can a script modify an environment variable of its calling shell? I am setting my JAVA_HOME in my ~/.bashrc file.  Now, I need to create a script that will change the JAVA_HOME just for the current terminal, so that I can start an app that needs java 5.  I have created this script to do this task, but after finishing, I can see that JAVA_HOME is not updated  export JAVA_HOME=/usr/lib/jvm/java-5-oracle/ export PATH=$PATH:$JAVA_HOME       Here is the result  $ ./javaHome5.sh $ echo $JAVA_HOME /usr/lib/jvm/java-6-oracle/   I think that the reason this is not being applied, is that a script is executing in it's own terminal, so when the script ends, the current terminal will not be affected.  Currently, the only way I've found around this is:   Edit my ~/.bashrc and change the JAVA_HOME var Run source ~/.bashrc to apply the changes in current terminal. Which again cannot be applied in a script, as the source command needs to be run in the current window.   Needless to say, this change applies to all new terminal windows, so I practically need to do this twice: One before starting my app, and one more time right after this, just to restore the environment vars to their default. That's not really convenient.  Do you have any ideas how can I change this var using a script? What is the definition of a symmetric distribution? Disabling Intel Turbo Boost in ubuntu Birthday problem: why is this solution wrong? This question is about the birthday problem: the probability that in a group of n people, at least two of them have the same birthday ().  An easy way to calculate the probability is to calculate first the probability that no two people have the same birthday.  Let's say that I want to calculate the probability that in a group of 20 people, NO two people have the same birthday.  So, for 20 people with different birthdays, I can choose the first birthday in 365 ways, the second in 364 ways and so on, while for 20 people who can have the same birthday, I can choose the first birthday in 365 ways, the second also in 365 ways, and so on. At the end:  $p={365 \cdot 364 \cdot 363 \cdot ... \cdot 346 \over 365 \cdot 365 \cdot 365 \cdot ... \cdot 365}\approx 0.59$  This is the right method and I understand it. I don't understand why the following method is wrong:  The probability that in a group of 20 people NO two people have the same birthday is the ratio between the combination without repetition of 20 birthdays and the combination with repetition of 20 birthdays:  $$p={C_{365,20} \over C'_{365,20}}={\binom{365}{20} \over \left(\binom{365}{20}\right)}={\binom{365}{20} \over \binom{365+20-1}{20}}=\frac{{{365!}\over {20!\cdot(365-20)!}}}{{(365+20-1)!}\over{20!\cdot{(365-1)!}}}\approx 0.35$$  I understand the mistake is in the denominator (as the numerator is the same of the other method, after simplifying that 20!), but why? Isn't it right to calculate the k-combination with repetition of 20 birthdays?  Thanks for helping! Product of path connected spaces is path connected Roll a 6-sided die until the total $\geq M$. Mean amount by which $M$ is exceeded? Here is the question:  You roll a fair 6-sided dice iteratively until the sum of the dice rolls is greater than or equal to M. What is the mean and standard deviation of the sum minus M when M=300?  Should I write a code to answer these kind of questions?  Please give me some hints on that. thanks! I have been hit with a homework problem that I just have no idea how to approach. Any help from you all is very much appreciated. Here is the problem  Prove the equation: $a^{\log_b c} = c^{\log_b a}$  Any ideas? Windows 10 lets you 'schedule' a reboot for later. I want to disable it.  Evidently Windows scheduled itself for a reboot last night when I wasn't looking and just closed everything I had been working on the night before.  I reboot on the regular; I don't need Windows to do that for me.  Can I disable it completely? I don't mind if it downloads everything, and then says "hey, you should reboot," but it should never reboot itself, ever.  I'm using the "Pro" edition of Windows 10. Correct location for piping and redirecting output in find -exec? I'm using find with the -exec option in console, on FreeBSD (for example, find . -exec sha1 {} \;).   How do I correctly place (and if needed, escape) redirect and other execution control symbols that could syntactically apply to either of the exec command or the find command, such as > >> | and &amp;, where I might want the symbol to apply to the find or the exec commands on different occasions?  On the same theme, what is the syntax if I want to use tee to view the output of the -exec commands on the console (to watch progress) and also appended to a file (for later use)?   (I know shells vary but hopefully the most used shells such as sh/csh are quite similar?)  Update:  In part, I want to learn if nested find -exec can be done without scripting, as a simple command. Here is the use-case that prompted the questio :   outer find: find all subdirs matching DIR_MATCH_TEXT in DIR1  inner find: for each matching subdir found in the outer loop (call it DIR2), execute the commandfind DIR2 -name "FILE_MATCH_TEXT" -exec sha1 {} \; &gt;&gt; DIR1/DIR2_hashes.txt   The aim being to create a set of files, one for each matching subdir, containing the output of some find -exec action on that subdir.  By this I mean that, if /backups contains /jan2017 and /feb2017, the result will be two files at /backups/jan2017_hashes.txt and /backups/feb2017_hashes.txt, with jan2017_hashes.txt containing the output from sha1 for (say) all .pdf files in /backups/jan2017, and feb2017_hashes.txt containing the output from sha1 for all .pdf files in /backups/feb2017.  From replies so far I gather the outer find would have to use a shell call as the argument to -exec? Parse DateTime with time zone of form PST/CEST/UTC/etc