What is the most managable way to install a program from source in Debian? Let's say that I've found a program that I want to install on my machine. It is only available as a source tarball that can be built with the usual ./configure; make; make install.  While I could do make install in these instances, I'm likely not going to know where xyz file/command come from in a few years, and whether it is important. And who knows what will happen if I try to build a newer version of the program.  What's the most common, manageable way of handling scenarios like this?
Keeping track of programs When I install a simple program it often uses make &amp;&amp; make install and doesn't often even have an uninstall target.  If I wish to upgrade a program, is it standard protocol to assume it just rewrites seamlessly over the old program?  How do I keep track of these programs; do most people just 'fire and forget' and if no uninstall target is given do I have to manually delete everything?
Can anyone explain how we choose one sock from each of finitely many pairs without the axiom of choice?  I mean : To choose one sock from each of infinitely many pairs of socks requires the Axiom of Choice, but for shoes the Axiom is not needed.  The idea is that the two socks in a pair are identical in appearance, and so we must make an arbitrary choice if we wish to choose one of them. For shoes, we can use an explicit algorithm -- e.g., "always choose the left shoe." Why does Russell's statement mention infinitely many pairs? Well, if we only have finitely many pairs of socks, then AC is not needed -- we can choose one member of each pair using the definition of "nonempty," and we can repeat an operation finitely many times using the rules of formal logic (not discussed here). In eevee, shadows are clipped by camera distance As shown in the gif, the shadow in eevee is clipped by the camera distance. The same is true for F12 rendering. Where are the options to improve this issue? Derangements with repetitive numbers I have a very simple problem.  Lets assume that I have a well shuffled deck of 52 cards. I start drawing the top card always and when the card matches its rank I lose. J=11 Q=12 K=13.  If there were only 13 cards I could easily use the $\ \frac{!n}{n!}$ for derangements in order to solve this. The problem is that there are 52 cards so when I pass 13 I start from 1 again so I don't know what is the probability to win. Example of the game     1st card: 4 - Continue   2nd Card: A - continue   3rd Card: K - Continue   4th Card: K - Continue   5th Card: 6 - Continue   6th Card: 9 - Continue   7th Card: 10 - Continue   8th Card: A - Continue   9th Card: J - Continue   10th Card: 3 - Continue   11th Card: 2 - Continue   12th Card: 8 - Continue   13th Card: A - Continue   1st card: 5 - Continue   2nd Card 2 LOSE   So actually I have to count from 1 to 13 4 times and if I draw all 52 cards then I win. What's the probability? How to disable javascript modal popup ads For many years I have blocked popup ads with AdBlock Plus.  But it seems more and more these past couple months there is a "new" kind of popup overtaking the web.  They are javascript based "modal" popups which ABP is powerless over.  See attached for an example.  Is there a way to kill these ads without breaking the functionality of anything I need? If the universe is 3D, how is space-time like a "fabric"? Adjoint pairs, triplets and quadruplets Often we have adjoint pairs $(A, B)$ (meaning $A$ is left adjoint to $B$). Sometimes we have adjoint triplets $(A,B,C)$ (meaning $A$ is left adjoint to $B$ and $B$ is left adjoint to $C$. No adjoint relation between $A$ and $C$ obviously, since they have the same source and target).  So the first question is: can we have quadruplets $(A,B,C,D)$ ? (meaning that $C$ is also left adjoint to $D$).  Second question: It would be then possible that we have $(A,D)$ besides $(A,B)$. But I think not, because I think that it is not possible to have a functor $A$ with two different right adjoints, $B$ and $D$. Is this correct? Where is "Connect to Server" for ssh connections in Unity? Cannot find "connect to server" in 11.04, looks like unity doesn't have it. Is there other very similar way to connect to another Ubuntu computer via SSH? (not in terminal) How can I find unanswered questions with zero answers in some tag? “The group of fifty people {is / are} going to arrive Thursday” - which is preferred? Isn't the following sentence grammatically correct?     The group of fifty people are going to arrive Thursday.   What's wrong with it? Someone said it should be      The group of fifty people is going to arrive Thursday.   Why? People is plural so why is people is better than people are? My book says  \begin{equation} (a,b)=\{\{a\},\{a,b\}\} \end{equation}  I have been staring at this for a bit and it doesn't make sense to me. I have read several others posts on this, but none made any sense to me.  For example,   Based on how my ignorant brain is viewing this, I don't see why the definition could not be.  \begin{equation} (a,b)=\{\{a\},\{b\},\{a,b\}\} \end{equation}  aka the power set. What is the significance of the {a} in that definition? Please keep things simple if possible. Normally definitions have a valid and clear reason for being defined that way.    Clarification  First, I understand what an ordered pair is. I just don't see how the set notation says that.   Second,  \begin{equation} (a,b) = \{\{a\},\{a,b\}\}=\{\{a,b\},\{a\}\} \end{equation} Sets don't preserve order, but ordered pairs do. How does the third part of the equality apply to the definition?  Third, another issue with the notation that I have starts with the Product Property of Sets  \begin{equation} \text{Let $X$ and $Y$ be sets} :\ X=\{a,b,c\}\text{ and }Y=\{a,d,e\}. \end{equation} \begin{equation} \text{Then }X \times Y = \{(a,a),(a,d),(a,e),(b,a),(b,d),(b,e),\dots,(c,e)\} \end{equation} If we look at the first ordered pair and our given definition we have  \begin{equation} (a,a)=\{\{a\},\{a,a\}\} \end{equation}   How can this be so, you can't have duplicates in sets? I guess what I am looking for in an answer, is not a proof or a definition of ordered pairs, but rather something like, "This notation says what it says because...". Except for the second to last point I get the terminology, I just don't get the connection between the two different uses of notation. ConTeXt: Flush right formula numbers in cases environment I would like to have the formula numbers of the cases environment flush right like regular formulas (not at a fixed distant from the cases like it is by default with the default setting numberdistance=2.5\emwidth). How can I do that?  \starttext  \startplaceformula     \startformula         \startcases             \NC x = 1 \NR[+]             \NC y = 1 \NR[+]         \stopcases     \stopformula \stopplaceformula  \stoptext     What I want (but with the left bracket):  \starttext  \startplaceformula     \startformula         \startalignment[n=1]             \NC x = 1 \NR[+]             \NC y = 1 \NR[+]         \stopalignment     \stopformula \stopplaceformula  \stoptext How to add a guest account without a password? My question is a little silly I know, but I'm curious to know if a particle of light can be theoretically trapped between two reflective screens.   For example once the particle of light has left it's source, and is reflected against a mirror (assuming there is no loss of energy) and you immediately replace the source of light with another mirror. Would the light beam bounce in between the sheets endlessly? I have built a peak detector circuit using op-amps/comparators to amplify the signal from an electret microphone, hold the peak signal and create a sharp logic edge when a peak is detected to be sent to a microcontroller.  I have built the circuit as follows setting up OA1 as a non inverting amplifier with a gain of 1000, but the voltage out from the OA1 remains fixed at about 4.5V no matter how much noise I make into the microphone. The comparator part of the circuit is outputting approximately 2V low and 5V high depending on how I set the potentiometer. All the components appear to be working.         &ndash; Schematic created using What is the origin of Dol Goldur, and why did Sauron start there? Who built the fortress of Dol Goldur, and when was it built? And was it always a place for evil, or Sauron just occupied it?  Despite the fact that Mordor is much better fortified; artificially by the old fortifications,  and geographically, as it is surrounded by the mountains. Also considering the presence of mount doom that seem to enhance Sauron's power, Sauron chose to start his campaign from Dol Goldur, despite Mordor being ready for quite some time.  Why did he choose this enigmatic fortress, and not go straight for Mordor or even go earlier? Divisibility tests and remainder mod $9,11,99,101,999,1001\,$ (casting out nines and elevens) Now I have proved the following two problems:      (1) Prove that a number and the sum of its digits have the same remainder upon division by 9.    (2) Given an integer, consider the difference between the sum of the digits in odd positions (counting from the right) and those in even positions. Show that the difference has the same remainder as the number itself when divided by 11.    Then, I need help on the following problem:      Partition the digits of a number into groups of two and three, respectively, starting from the right. Treat these as two- and three-digit numbers, respectively, and proceed similarly as in the two problems above. What divisibility rules arise?    In fact, I did not quite get what this problem asks for and not clear about this process. Could anyone give me some hints on this, please?  Thanks in advance. How can I put a bit mask on /dev/zero so that I can get bytes other than zero? How can I put a bit mask on /dev/zero so that I can have a source not only for 0x00 but also for any byte between 0x01 and 0xFF? Unix Truncate Column in csv file How to calculate the variance of a partition of variables I'm running an experiment where I'm gathering (independent) samples in parallel, I compute the variance of each group of samples and now I want to combine then all to find the total variance of all the samples.   I'm having a hard time finding a derivation for this as I'm not sure of terminology. I think of it as a partition of one RV.   So I want to find $Var(X)$ from $Var(X_1)$, $Var(X_2)$, ..., and $Var(X_n)$, where $X$ = $[X_1, X_2, \dots, X_n]$.  EDIT: The partitions are not the same size/cardinality, but the sum of the partition sizes equal the number of samples in the overall sample set.  EDIT 2: There is a formula for a , but it only covers the case of a partition into two sets, not $n$ sets. What autofocus zone selection mode should I use for action/event shooting? I have a Canon 7D, and typically shoot everything I do in its single-point autofocus zone select mode, because I usually want fine control over exactly what the camera is focusing on and I often find that its two automatic focus zone select modes don't focus on what I want in focus.  For most of the photography I do, this is fine -- I have enough time that I can compose the shot the way I want, use the joystick on the back to select the right focus point, and take the shot at my leisure.  However, recently I've been doing more event/action photography, and I've been running into issues with this mode of operation.  Too often, I will see a person start to do something interesting, but my autofocus point is not in the right place -- so by the time I get the camera up, adjust the settings, and move the autofocus point, the opportunity to take the shot has passed.  My question is, what autofocus zone selection mode and workflow should I use for this type of photography?  I could use the 5-zone partial-auto mode (which gives me a choice of top, middle, bottom, left, or right, and then the camera chooses the points within my selected region), but I find that the time needed to switch in between that mode and the single-point mode is similarly prohibitive, and I have to hope that the camera chooses the right thing to focus on.