why should the bounty not refunded if the question has no answer at all?
Why aren't bounties refunded if they are not awarded?
How can I execute `date` inside of a cron tab job? I want to create a log file for a cron script that has the current hour in the log file name. This is the command I tried to use:  0 * * * * echo hello &gt;&gt; ~/cron-logs/hourly/test`date "+%d"`.log   Unfortunately I get this message when that runs:  /bin/sh: -c: line 0: unexpected EOF while looking for matching ``' /bin/sh: -c: line 1: syntax error: unexpected end of file   I have tried escaping the date part in various ways, but without much luck. Is it possible to make this happen in-line in a crontab file or do I need to create a shell script to do this? Why is the sum of two random variables a convolution? For long time I did not understand why the "sum" of two random variables is , whereas a mixture density function sum of $f(x)$ and $g(x)$ is $p\,f(x)+(1-p)g(x)$; the arithmetic sum and not their convolution. The exact phrase "the sum of two random variables" appears in google 146,000 times, and is elliptical as follows. If one considers an RV to yield a single value, then that single value can be added to another RV single value, which has nothing to do with convolution, at least not directly, all that is is a sum of two numbers. An RV outcome in statistics is however a collection of values and thus a more exact phrase would be something like "the set of coordinated sums of pairs of associated individual values from two RV's is their discrete convolution"...and can be approximated by the convolution of the density functions corresponding to those RV's. Even simpler language: 2 RV's of $n$-samples are in effect two n-dimensional vectors that add as their vector sum.           Please show the details of how the sum of two random variables are a convolution and a sum. What is the sign of the  done on the system and by the system?  My chemistry book says when work is done on the system, it is positive. When work is done by the system, it is negative.  My physics book says the opposite. It says that when work is done on the system, it is negative. When work is done by the system, it is positive.  Why do they differ? Fermat primes relation to $2^n+1$ If $2^n+1$ is prime how to show that  $n$ must be a power of $2$  Being at elementary level I am at a loss what to begin with? How long can you store used cooking oil How long can you store used cooking oil then re-use it? I deep fried a turkey one year ago and have had it refrigerated since. Sum of the series $\sum _{ r=1 }^{ \infty }{ \frac { { r }^{ 3 } }{ r! } } $ Proper way to Plot a single function in two different styles? I am learning basics of the category theory (CT).  I do understand that CT is a modern powerful framework to describe various branches of mathematics in a unified way.  I do admit that category's definition tells a lot about the whole thing and focuses on the most important properties, shadowing unnecessary details. However, the more I go forward, the more it feels like it should explicitly require a notion of morphisms equality (like it does with morphism composition). It feels so because equality or inequality of morphisms arises everywhere, since the very beginning: any commutative diagram eventually reduces to an equality of two different paths and many other things involve equality as well. Even composition is defined grounding upon an (implicit) equality!  I'll try to give an example of my concern. Consider $\mathbb{SET}$. Its objects are sets and morphisms are functions. Now, let's recall that functions are sets as well - to be more precise, a function $f : A \mapsto B$ is a subset of a $A \times B$ obeying certain properties, which I omit. Thus, one could argue that $f$ is both a morphism between objects $A, B \in Obj(\mathbb{SET})$ and an object defined as a set of pairs $\{ (a_1 \in A, b_1 \in B), ..., (a_n \in A, b_n \in B) \}$ and those are equal because both are essentially exactly the same thing.  I hope my concern is clear and I need some kind of "conceptual insight" from knowledgeable people to move forward. Please give me the right perspective. How do I move child windows without moving or minimizing parent in GNOME 3? Currently, a user does not get any notification when a trivial edit (less than 6 characters, by a user who has the ) is made on one of his/her posts. As in .  Even though the user is trust-worthy (owing to the rep of the user), wouldn't it be nice for the OP to get a notification whenever an edit is made, even trivial? As things stand, will House Stark go extinct? According to the family tree in A World of Ice and Fire Ned Stark's children are in fact the only surviving Starks. And as of S06E09;      Bran is the only legitimate, male Stark.   In the Season Six Finale it is revealed that;      Jon is in fact the Son of Lyanna Stark and most likely, Rhaegar Targaryen.   This means that if Jon was legitimised and there was record of his birth in the Citadel;      He would become a Targaryen.   So I guess my big question is: Can Bran father children? I find it to be quite an important issue considering House Stark's long term survival depends on it.  In season 4 (I can't remember which episode) Locke Bolton gives Bran a cut on the leg to confirm his identity. Bran reacts only with fear and not pain, indicating that he has no feeling below his waist.  Does this mean that he wouldn't be able to...get it up? And if so, why hasn't the show addressed House Stark's impending doom? USB Charge and data separate cables Is it possible to split micro USB to USB cable so two cables (data + and data -) go to the PC with USB and two other power cables go to power brick? Nautilus does not show the left bar, how do I turn it back on? Can't install apps from App Store on iPhone with iOS 7 Drawing line less than one pixel thick requires anti-aliasing in Android 4.2 The graph of the function $f (x)$ is given.  How many different real roots does the $f (4-3x^2)=0$ equation have?  Here is possible solution:  $$\Bigg [{4-3x^2=-2 \\ 4-3x^2=4} \Longrightarrow x=\left\{0,\sqrt 2,- \sqrt 2\right\} $$  Then, here is different solution:  $$f(x)=x^2-2x-8$$ $$f(4-3x^2)=0\Longrightarrow (4-3x^2)^2-2(4-3x^2)-8=0 \Longrightarrow 9x^4-18x^2=0 \Longrightarrow x=\left\{0,\sqrt 2,- \sqrt 2\right\} $$   Problematic point. Here, I assumed the function is quadratic. But, obviously, this function may not be quadratic.  My questions:  Question $-1:$ Is the first solution completely correct?  Question $-2:$ Can we say that, the second solution is completely and definitely wrong? If so, is it possible to add something to this method and turn it into the right solution? Add a note about downvoting on Meta It is stated as a problem in Spivak's Calculus and I can't wrap my head around it. How to programmatically close a JFrame I am trying to recreate a penne pasta. I am creating a cylinder removing the two end faces and then I solidify the mesh.  However I do not know how to extrude (or cut away) the two ends to make them pointy like in the picture of the penne below. I have tried to use bisect and mirror, but without successful results.  Any idea?