How can I use launchd to auto update brew?
launchd plist format for running a command at a specific time on a weekday
Message appearing when a user was removed.     It seems I lost 1765 reputation points on Stack Overflow yesterday. The reason given in my history is "removed", with the description of "User was removed ()". I don't understand what that means. What caused this? Find the number of zeroes (counting multiplicity) of $p(z)=z^6+z^3+10z^2+4z+3$ inside the annulus $1&lt;|z|&lt;2$. I think this can be solved using Rouché’s theorem. First consider $|z|\leq 1$ on the boundary $|z|=1$ and $|z^6+z^3|&lt;|10z^2+4z+3|$ which can be shown using triangle inequalities, the left side is at most $2$ while right side is at least $3$. We could also consider $|z|\leq 1+ \epsilon$ and our proof still works. Thus $p(z)$ has 2 roots inside $|z|\leq 1$. Also for $|z|= 2$ we have $|z^6+z^3|&gt;|10z^2+4z+3|$. Thus we have 6 zeroes of $p(z)$ inside $|z|&lt;2$ and therefore 4 of them are in $1&lt;|z|&lt;2$. Is this correct? The only &quot;tricky&quot; part is ruling out that there are zeros on $|z|=1$. How to install XAMPP? Hi all im a noob on Ubuntu/Linux World,  So i need some that give a full tutorial to How to install  from apachefriends.org correctly on Ubuntu 11.10 + all beyond Ubuntu for 32 bit and also 64 bit Desktop Version.. and also i need this:   Make a Folder on Your Home Folder and Linked to htdocs from Apache Web Server Make a GUI interface for Xmapp Start Xampp when Ubuntu Boot Up or Start Ubuntu   (Note: i ask it for both X86 and X64 so people in the further can see the tutorials)    New Data:  What i did was i download from  for now and i also what to say that I'm currently running Ubuntu 11.10 X64 bit for Dell Studio 1558 processor intel i3  i will let you know guys which solution was the best, and it is for a Desktop Version of Ubuntu 11.10 (Laptop 15 inch screen ^_^ ) not Server Ubuntu Is there a C++ decompiler? I have a program in which I've lost the C++ source code.  Are there any good C++ decompilers out there?  I've already ran across . $n$ balls are thrown randomly into $k$ bins - how many are empty? A large number of variants of this question were already asked here, including these - , , which are close, but none seem to answer my question. Assume that $n$ balls are thrown randomly and independently into $k$ bins.  What is the probability of finding $x$ empty bins? What is the expectation of the number of empty bins? Can you choose which version of a game to play on Steam? I want to play a game in an older update, but can't see a way to choose a specific version. Is this possible? When you are performing time consuming operations in bash like installing new software, is it possible to write text that will appear at the prompt when the operation has finished.  E.g   Imagine running:  apt-get install eclipse-platform   Then it will use quite a while to finish while you see the installation log, meanwhile I want to create new folders (workspaces) which Eclipse later will use.  Is this possible without opening a new terminal (or tab)? This was a 'young-adult' SF novel I read in the late 1970's, about the same time I was reading Voorloper by Andre Norton, Madeleine L'engle's Wrinkle In Time books and the Dragonfall 5 young adult novels. so I am not sure if it is actually one of the Dragonfall 5 stories, but I can't confirm it is or isn't by reading available synposes online.   As I recall, the story went something like this...    * SOME SPOILERS BELOW *  A young person and sibling - I think female protag and younger brother, but not sure - is scheduled to visit their aunt and uncle on another planet but to make the voyage in a timely fashion, must utilize this new consciousness transference technology to transmit their consciousness across the cosmos to a host replica body at the destination. After arriving at the destination the protagonist is impressed by their new body and is aware of the only way to tell they are in a replicant body is a small seam, scar or patch on their back, I think near the top of their spine, just below the collar of whatever clothing they wore.  The mystery begins when the protagonist realizes their hosts also sport the same scar when they should legitimately be in their real bodies.  The plot thickens when the protag or sibling finds a room of people in stasis when their replicant counterparts are roaming the same planet, and is subsequently caught in the act.  Sadly, I do not remember anything else, including the reasoning behind the deception.  I was quite young when I read this novel, so I probably got some of the details mixed up, but would love to know the name and author of the novel if anyone remembers. How can I make environment variables "exported" in a shell script stick around? I have multiple Amazon EC2 accounts and want to quickly be able to switch variables, such as $EC2_HOME, using a script.  I have have a shell script set up like this:  #!/bin/sh export EC2_HOME=/home/me/.ec2 echo $EC2_HOME   When I run the script I know that EC2_HOME is set, but I thought that using export would make the variable stick around after the script completed. It does not, as running echo $EC_HOME does not show anything.  I know this must be very rudimentary Linux scripting knowledge, but I don't know it. I tried looking for related questions without luck - so my apologies if this is a duplicate. How do you challenge the closing of one of your questions? Are token creatures considerd as a creature spell? How can I revert a config file back to the originally installed version after I have edited it? I want to revert a file in /etc/ back to its originally-installed form. I have edited the file since it was installed. How can I revert this config file? Apt is smart enough not to overwrite edited config files, so how do I tell it that I want it to do so?  For argument's sake, let's say that I want to revert the file /etc/foo.conf from the package foo. Getting the default text editor used in system I have used select-editor and I note that I am using /usr/bin/nano. Is this the default text editor I am using?  When I open text files, It opens with gedit  What command in terminal must be specified to get the default text editor that I am using, and have it returned to e in terminal? Two very closely related questions:  If a card has two different "Sacrifice this creature for X" abilities on it, does sacrificing it give both benefits?  Likewise, if a card requires a creature to be sacrificed, but that creature has a "Sacrifice this creature for X" ability, do you get the sacrifice benefit when you sacrifice it for the other requirement? Sound of a next scene starts one moment earlier than video Calculating the total number of surjective functions It is quite easy to calculate the total number of functions from a set $X$ with $m$ elements to a set $Y$ with $n$ elements ($n^{m}$), and also the total number of injective functions ($n^{\underline{m}}$, denoting the falling factorial). But I am thinking about how to calculate the total number of surjective functions $f\colon X \twoheadrightarrow Y $.  The way I thought of doing this is as follows: firstly, since all $n$ elements of the codomain $Y$ need to be mapped to, you choose any $n$ elements from the $m$ elements of the set $X$ to be mapped one-to-one with the $n$ elements of $Y$. This results in $n!$ possible pairings. But the number of ways of choosing $n$ elements from $m$ elements is $\frac{m!}{(m-n)!\,n!}$, so the total number of ways of matching $n$ elements in $X$ to be one-to-one with the $n$ elements of $Y$ is $\frac{m!}{(m-n)!\,n!} \times n! = \frac{m!}{(m-n)!}$.  Now we have 'covered' the codomain $Y$ with $n$ elements from $X$, the remaining unpaired $m-n$ elements from $X$ can be mapped to any of the elements of $Y$, so there are $n^{m-n}$ ways of doing this. Therefore I think that the total number of surjective functions should be $\frac{m!}{(m-n)!} \, n^{m-n}$.  Is this anything like correct or have I made a major mistake here? On every boot up I get this:    For about 10 seconds (or more) before the "normal" Ubuntu Gnome loading screen and the login screen comes up.  I've read some questions and a bug report about this already, but this problem was dismissed as a minor inconvenience or there were no real solutions (that worked for me). For me, this problem leads to an unacceptable slow boot compared to Ubuntu (Unity) or Windows.  Does anybody know how to fix this or is this a "feature" of Ubuntu Gnome and not a bug? In the textbook, it said a wave in the form $y(x, t) = A\cos(\omega t + \beta x + \varphi)$ propagates along negative $x$ direction and $y(x, t) = A\cos(\omega t - \beta x + \varphi)$ propagates along positive $x$ direction. This statement looks really confusing because when it says the wave is propagating along $\pm$ x direction, to my understanding, we can drop the time term and ignore the initial phase $\varphi$ while analyzing the direction, i.e. $y(x, 0) = A\cos(\pm\beta x)$, however, because of the symmetry of the cosine function, $\cos(\beta x)\equiv \cos(-\beta x)$, so how can we determine the direction of propagation from that?  I know my reasoning must be incorrect but I don't know how to determine the direction. So if we don't go over the math, how to figure out the direction of propagation from the physical point of view? Why $-\beta x$ corresponding to the propagation on positive x direction but not the opposite? NSInvocation for Dummies? How exactly does NSInvocation work? Is there a good introduction?  I’m specifically having issues understanding how the following code (from Cocoa Programming for Mac OS X, 3rd Edition) works, but then also be able to apply the concepts independently of the tutorial sample. The code:  - (void)insertObject:(Person *)p inEmployeesAtIndex:(int)index {     NSLog(@"adding %@ to %@", p, employees);     // Add inverse of this operation to undo stack     NSUndoManager *undo = [self undoManager];     [[undo prepareWithInvocationTarget:self] removeObjectFromEmployeesAtIndex:index];     if (![undo isUndoing])         [undo setActionName:@"Insert Person"];      // Finally, add person to the array     [employees insertObject:p atIndex:index]; }  - (void)removeObjectFromEmployeesAtIndex:(int)index {     Person *p = [employees objectAtIndex:index];     NSLog(@"removing %@ from %@", p, employees);     // Add inverse of this operation to undo stack     NSUndoManager *undo = [self undoManager];     [[undo prepareWithInvocationTarget:self] insertObject:p                                        inEmployeesAtIndex:index];     if (![undo isUndoing])         [undo setActionName:@"Delete Person"];      // Finally, remove person from array     [employees removeObjectAtIndex:index]; }   I get what it’s trying to do. (BTW, employees is an NSArray of a custom Person class.)  Being a .NET guy, I try to associate unfamiliar Obj-C and Cocoa concepts to roughly analogous .NET concepts. Is this similar to .NET’s delegate concept, but untyped?   This isn’t 100% clear from the book, so I’m looking for something supplemental from real Cocoa/Obj-C experts, again with the goal that I understand the fundamental concept beneath the simple(-ish) example. I'm really looking to be able to independently apply the knowledge -- up until chapter 9, I was having no difficulty doing that. But now ...    Thanks in advance! I am flying from Los Angeles to Bangalore. I have a flight option from LAX to Minneapolis and from there to Paris. I have only 45 minutes at Minneapolis before my next flight. Is this too risky a schedule? I am not an American, so I guess I would need to cross emigration too?