Find files systemwide that are created within a date range
How to list files that were changed in a certain range of time?
"the better" vs "the best" of two players How to remove \xa0 from string in Python? 32-bit vs. 64-bit systems What are the differences between 32-bit and 64-bit systems?  If you have used both of them, what kind of sharp differences have you experienced?   Would it be a problem to use 32-bit programs on 64-bit systems in some cases? I'm using a docker image as a base for my own development that adds the jessie backports repository in its Dockerfile and uses that to install a dependency. This image uses the following command to add the repository:  echo "deb http://ftp.debian.org/debian jessie-backports main" &gt;&gt; /etc/apt/sources.list   The problem is that fetching packages from the backports repository now  fails with the following error (this used to work previously):  W: Failed to fetch http://ftp.debian.org/debian/dists/jessie-backports/main/binary-amd64/Packages 404  Not Found  W: Failed to fetch http://deb.debian.org/debian/dists/jessie-updates/main/binary-amd64/Packages  404  Not Found   I looked on that server, and those paths are indeed not present there.  I tried to figure out on the Debian backports site whether this particular repository should still be available, and I didn't find any indication that this was deprecated or something like that.  Is this a temporary issue with the repository, or is the jessie-backports repository not available anymore? And if this is not a temporary issue, what options do I have to use this or an equivalent repository without upgrading to the newer Debian stable version? Combinatorial Proof for Binomial Identity: $\sum_{k = 0}^n \binom{k}{p} = \binom{n+1}{p+1}$ I am studying combinatorics and I came across the identity $$\sum\limits_{k=0}^n \binom kp =\binom {n+1}{p+1}.$$ I have read the algebraic proof and it does not appeal to me. Is there an elegant counting trick we can use to arrive at this identity? Splitting lines by polygons in QGIS I have a river network (lines) and a .shp with states (polygon). I would like to split the lines at the state boundaries i.e. split lines by polygon boundaries. Is there a geoprocessing tool to do this in QGIS? I can't merge the lines by the way, since they are meaningfully split into tributaries/main river. How to run the Ubuntu ISO live image from Windows without USB or DVD?  This is a self answered question. The  (ESC), states that for every natural number $n \geq 2$, there exists a set of natural numbers $a, b, c$ , such that the following equation is satisfied:  $$\frac{4}{n}=\frac{1}{a}+\frac{1}{b}+\frac{1}{c}\tag{1}$$  The basic approach to solving this problem outlined by Mordell [Ref1] is described below  By defining $t$ and $m$ as positive integers greater than zero and $q$ a positive integer greater than one we can observe that  a) There is always a solution for even $n$, since if $n=2^qt$ we have the trivial solution $$\frac{4}{4t}=\frac{1}{t}$$  In the remaining case $n=2(2t+1)$, a solution in the form of two Egyptian fractions can always be found  e.g. $$\frac{4}{2(2t+1)}=\frac{2}{2t+1}=\frac{1}{t+1}+\frac{1}{(t+1)(2t+1)}$$  b) If $(1)$ is a solution for some particular prime $n$ then all composite numbers $mn$ divisible by $n$ are also solutions, thus  $$\frac{4}{mn}=\frac{1}{ma}+\frac{1}{mb}+\frac{1}{mc}$$  will also be a solution. This means that we can simplify the analysis to the cases where $n$ is a prime greater than 2.  Using Mordell's approach we have just shown that we only need to consider the cases where $n$ is prime and where $n \equiv 1 \pmod{2} \;\;[meaning \;\;n=2t+1]$  The argument continues...  Mordell goes on to show in turn that the search can be reduced further to the cases when $$n \equiv 1 \pmod{4} \;\;[meaning \;numbers \;\;n=4t+1]$$ $$n \equiv 1 \pmod{8} \;\;[meaning \;numbers \;\;n=8t+1]$$ $$n \equiv 1 \pmod{3} \;\;[meaning \;numbers \;\;n=3t+1]$$ $$n \equiv 1,2,4 \pmod{7} \;\;[meaning \;numbers \;\;n=7t+1,n=7t+2 \;or\;n=7t+4 ]$$ $$n \equiv 1,4 \pmod{5}  \;\;[meaning \;numbers \;\; n=5t+1 \;or\;n=5t+4]$$  Assembling these results together, Mordell showed that the conjecture can be proved in this context except for the cases when $$n \equiv 1,11^2,13^2,17^2,19^2,23^2 \pmod{840}$$  Mordell stated that since the first prime meeting this condition is 1009, this is proof that the conjecture holds for $n&lt;1009$.  This basic approach can be pursued further. Other workers have shown that the conjecture holds for much higher values of $n$ using similar methods as can be seen on the above Wikipedia page.   Note that other intermediate results can be constructed from the above congruence's, e.g. $n \equiv 1 \pmod{24}$.  The question is:  Are there any other elementary approaches to solving this problem than the one outlined by Mordell (and described above)?  [Ref1] Louis J. Mordell (1969) Diophantine Equations, Academic Press, London, pp. 287-290. To show that $\sum a_nb_n$ is absolutely convergent Assume that $\sum a_n$ is convergent and $\sum b_n$ is absolutely convergent.To show that $\sum a_nb_n$ is  absolutely convergent  My try::Consider the sequence of partial sums of $\sum |a_nb_n|$  $S_n=|a_1b_1|+|a_2b_2|+......+|a_nb_n|$  Now $(a_1b_1+a_2b_2+......+a_nb_n)\leq ( (a_1^2+a_2^2+..+a_n^2))^\frac{1}{2}((b_1^2+b_2^2+..+b_n^2)^\frac{1}{2})$  How to proceed from here? In my javascript I have this      loopDeLoop:         while (foo !== bar) {             switch (fubar) {                 case reallyFubar:                     if (anotherFoo == anotherBar) {                         break loopDeLoop;                     }                     break;                 default:                     break;             }         }   But JSLint says... lint warning: use of label  Here's the notes from        Labels   JavaScript allows any statement to have a label, and labels have a separate name space. JSLint is more strict.      JSLint expects labels only on statements that interact with break: switch, while, do, and for. JSLint expects that labels will be distinct from vars and parameters.   How do I construct the above to get rid of the warning?  Thanks, Greg Troubleshooting "program does not contain a static 'Main' method" when it clearly does...? Comma after introductory words, phrases, clauses: unacceptable, obligatory or optional? I am no native speaker and always confused about the comma in introductory phrases, in particular in prepositional phrases. Is there any hard rule when a comma must be set? If I make a google search for certain phrases, I often find both variants. Typical examples where I am not sure whether a comma must be set are:        First[ly][,] I must phone mother   In this case[,] we must...   For simple problems[,] the algorithm...   From Lemma 1.2[,] we obtain...   For a typical user[,] the algorithm...   In our theory[,] we...   A dark line on the horizon[,] the mountain range we were headed for seemed somehow not as threatening as when we had started out on the trip.   Avidly reading her novel[,] Jane did not notice that her stop was approaching.   To be sure[,] it is not easy to see a solution.   When you get to Rome[,] give me a ring. Where to get school zone shapefiles? Census.gov usually makes available the shapefiles containing school zone boundaries. Due to the US government shutdown, census.gov is down. Does anyone know where to download a recently archived copy? While talking about ships and countries, is it a good practice to use the feminine form?  For example:  "Her economy" - while referring to a country's economy "Her flag (or deck etc)" - while referring to a ship  Is this practice common? Is it used today? When proving $\bar x$ and $S^2$ are independent in my noted it says that "functions of independent quantities are independent ". Can someone tell me how functions of independent quantities are independent happen?  Also let $X_1,X_2,X_3,\dots,X_n$ be a random sample.And suppose we want to estimate parameter $\theta$ using $T(x)$ as an estimator. In this I have a expression as $E\{ [  T(X)-E(T(X))][E(T(x)-\theta)]\}$.  I want to know if I can say that in $[T(X)-E(T(X))]$ since $E(T(X)$ (expected value is a one particular fixed value) and $T(X)$ are independent of one another. Also the expression $[E(T(x)-\theta)]$ is independent of $X$.  Hence the two expressions $[T(X)-E(T(X))]$ and $[E(T(x)-\theta)]$  are independent of one another. So that I can use if $a,b$ are independent $E(ab)=E(a)E(b)$ form Unexpected output for this following code Bottom to top explanation of the Mahalanobis distance? The Complete Rate-Limiting Guide How to make a cycles light emisson object invisible to the camera? In my scene it is required to position the lights close to the main object like this:    How I can make the light source invisible to the camera? I've recently bought a new Android smartphone. After setting it up and loading my contacts onto it I thought that would be it.  Now after some days, every time I unlock the phone it takes a few seconds before it opens the default browser and opens some spam website. I tried to see what was causing it. I removed any apps I didn't know I could trust, but the problem persisted. After trying to solve it for some time I gave up and reset the phone to factory default. Now after having it reset to the default it ran without issues for roughly a week before the problem reappeared.    I tried to uninstall some apps in order to see if they were to cause of it, but nothing changed after doing so. However I did notice that if I turn off the wifi it won't even try to open the browser (I haven't tried mobile data since I don't have a bundle). This makes me feel like it might be related to something on the network but that wouldn't explain why only that phone would have the issue when there are at least 6 android phones on that very same network.  I hope that there is someone who can help me find the cause of this issue and help me solve it.  TL;DR When unlocking my phone, it opens the browser and tries to open a spam website. But only does so while connected to the wifi.  Things I've tried so far:   Factory reset (only helped for a limited time) Clearing the browser cache and all related data  Removing any app I don't know to be reliable Attempting to find what triggers it (seems like some type of internet connection is required??)   The device is the Doogee Shoot 1. As for the browser, the default is set to be the Android browser, but if I change the default it would use Chrome just as well. It seems to really just use the browser that is set to default.