Solving system of linear equations ( 4 variables, 3 equations)
Solve a linear system with more variables than equations
Based on Logman dictionary:       happen to do something: if you happen to do something, you do it by chance.   for example take a look at these examples:     They happen to be unemployed at the time. I happen to have a degree in computer science.    So based on the definition of the happen to do something, first one means they are probably unemployed at the time. and the second one means I probably have a degree in computer science.     Am I right? Unidentified address in Gmail Many times, when I copy&amp;paste an email address into the "To" field in a Gmail message, it refuses to send the email, saying that “the address has not been identified”. This is very frustrating. Is there any solution other than just manually typing the address? Best way to clone an installation (copying to identical hardware) Kind-of like  but slightly different (I think), in that I have 6 identical Acer Aspire Revo R3610 machines. One is (almost) configured to my requirements - when I'm done preparing it I'd like to make the other 5 machines absolutely the same. I'm very new to Ubuntu, what's the most straightforward (easiest) way of doing this?  The machines are going to live on different networks if that might otherwise be a problem (eg with Windows you can clone disks but you then have to make registry changes afterwards if they're going to run on the same network etc). The hardware in all 6 machines is, I stress, the same!  How can I efficiently clone one source image on to these identical machines?  Please restrict one software/solution per answer The summer training or (just) summer training Should we use the summer training or just summer training in the paragraph. As per me training is a noun and before singular noun we have to use an article and I am using the because I am talking about a specific training for engineers, I also know that before very common nouns we avoid articles, like bed, school, bus, university, so if you say we should use summer training then please give me a valid reason.     Company(name) has been providing the summer training for engineers   since 2010. We have been giving completely professional atmosphere for   engineers to complete the summer training with practical knowledge.   Our each faculty has a great experience in the education field. We   make sure you get all the important resources to make your summer   training a learning and an enjoyable summer training. You may call or   email us to get your confirmation about the training.   Thanks in advance. Will leaving corpses lying around upset my prisoners? I see questions/information online about how to get rid of corpses but I'm not sure what the consequences to having them lying around are.  I know that I can use a morgue to store them and that they will eventually be taken away in a hearse. However, I've always just left them lying around. This doesn't seem to have any obvious consequences.  Do they upset prisoners or staff (e.g. increasing the danger level beyond what death normally does)? Make them sick? Slow down pathing? Is this something that's not implemented yet or is leaving dead bodies all over the place meant to be completely fine?  The wiki's pages for  and  don't shed any light on this. All I'm finding is the how of getting rid of corpses/glitches related to it but not why it matters in the first place. All I've seen that's related is that apparently prisoners can loot guard corpses for keys, but there's no obvious consequences for prisoner corpses which are what I tend to end up with.  So why not just leave them in the corridors? How do you remove Subversion control for a folder? I have a folder, c:\websites\test, and it contains folders and files that were checked out from a repository that no longer exists. How do I get Subversion to stop tracking that folder and any of the subfolders and files?   I know I could simply delete the .svn folder, but there are a lot of sub-folders in many layers. The code for reference is this  @article{matcontcl,  title= {MATCONT and CL MATCONT},  author = {A. Dhooge, W. Govaerts, Yu.A. Kuznetsov, W. Mestrom, A.M. Riet and  B.Sautois},  year = {2006},  journal = {Continuation toolboxes in matlab}, }   This is the error that follows  This is BibTeX, Version 0.99d (TeX Live 2015/W32TeX) The top-level auxiliary file: PropuestaInvestigacion.aux The style file: abbrv.bst Database file #1: biblio.bib Too many commas in name 1 of "A. Dhooge, W. Govaerts, Yu.A. Kuznetsov, W. Mestrom, A.M. Riet and B.Sautois" for entry matcontcl while executing---line 1049 of file abbrv.bst Too many commas in name 1 of "A. Dhooge, W. Govaerts, Yu.A. Kuznetsov, W. Mestrom, A.M. Riet and B.Sautois" for entry matcontcl while executing---line 1049 of file abbrv.bst Too many commas in name 1 of "A. Dhooge, W. Govaerts, Yu.A. Kuznetsov, W. Mestrom, A.M. Riet and B.Sautois" for entry matcontcl while executing---line 1090 of file abbrv.bst Too many commas in name 1 of "A. Dhooge, W. Govaerts, Yu.A. Kuznetsov, W. Mestrom, A.M. Riet and B.Sautois" for entry matcontcl while executing---line 1090 of file abbrv.bst (There were 4 error messages)   How could I fix it? I can't get into my field research prize Usage of -n and -z in test built in - Bash Create a virtual file that is actually a command Is there any way to create a virtual file, such that reading from the file actually reads from the stdout of a command; writing to the file is acually writing to the stdin of a command?  So far I have kludged this with an inotifywait on a file, which calls a command when the file is modified, taking it's input from the file and writing back to it.  I don't like that the inotifywait has to be constantly restarted though (and I have to ensure that it is always running). I only use this file perhaps twice a week. No transaction fee ETF trades - what's the catch? I just noticed TD Ameritrade has program where you can trade from a list of ETFs with zero fees.  Sounds like it could save me a bit of money, but my cynical side wonders how they make money off such a program...  Is it a loss leader? (They entice me to have an account there, and then make money off the other trades I make?)  Or do they simply want to grow the size of their asset base -- what is the mechanism by which they make money on the funds that I have in my account?  Edit: in case it wasn't clear in the original question above, this is an ongoing program for free ETF transactions -- not a one-time deal for some number of free trades when you open an account. I have had an account there for years and I'm eligible to participate -- it's not a program explicitly designed just to gain new accounts. Any complete group (that is, with trivial center and outer automorphism group) is isomorphic to its automorphism group. The inverse is not true, as the dihedral group of order 8 is isomorphic to its automorphism group but isn't complete.  Problem 15.29 in the Kourovka Notebook asks to find another exemple of a p-group, but I was wondering, is any other exemple known? Is there any other finite (or even infinite) group (not necessarily a p-group) which is isomorphic to its automorphism group but isn't complete? Which pseudo-$R^2$ measure is the one to report for logistic regression (Cox & Snell or Nagelkerke)? I have SPSS output for a logistic regression model. The output reports two measures for the model fit, Cox &amp; Snell and Nagelkerke.  So as a rule of thumb, which of these $R^²$ measures would you report as the model fit?  Or, which of these fit indices is the one that is usually reported in journals?    Some Background: The regression tries to predict the presence or absence of a bird (capercaillie) from some environmental variables (e.g., steepness, vegetation cover, ...). Unfortunately, the bird did not appear very often (35 hits to 468 misses) so the regression performs rather poorly. Cox &amp; Snell is .09, Nagelkerke, .23.    The subject is environmental sciences or ecology. How do I get the difference between two Dates in JavaScript? I'm creating an application which lets you define events with a time frame.  I want to automatically fill in the end date when the user selects or changes the start date.  I can't quite figure out, however, how to get the difference between the two times, and then how to create a new end Date using that difference. Maximum Likelihood Estimate with different parameters Do you capitalize both parts of a hyphenated word in a title? Do you capitalize both parts of a hyphenated word in a title?  "My Ex-Wife Hates Me"  or  "My Ex-wife Hates Me" Where can I ask a question about finding general software that meets certain requirements? What is duplicate content and how can I avoid being penalized for it on my site? How do we know the Taylor expansion for $e^x$ works for all $x$? Or that it's analytic? Prove that $|f''(\xi)|\geqslant\frac{4|f(a)-f(b)|}{(b-a)^2}$ Let ${\rm f}:\left[a, b\right]\to\mathbb{R}$ be twice differentiable, and suppose   $$\lim_{x\to a^{+}} \frac{{\rm f}\left(x\right) - {\rm f}\left(a\right)}{x - a} = \lim_{x\to b^{-}}\frac{{\rm f}\left(x\right) - {\rm f}\left(b\right)}{x - b} =0 $$  Show that there exists $\xi \in \left(a, b\right)$ such that $\displaystyle{% \left\vert\vphantom{\Large A}\,{\rm f}''\left(\xi\right)\right\vert \geq \frac{4\left\vert\vphantom{\Large A}% \,{\rm f}\left(a\right) - {\rm f}\left(b\right)\right\vert} {\left(b - a\right)^{2}}}$.  I don't know how to start. Any hints ?.