Batch remove empty directories (Removing as many directories as possible, but no files)
Recursively delete empty directories in Windows
How to load a .NET assembly for reflection operations and subsequently unload it? I was wondering if there was any was I could right click inside any instance of a "Finder" window such that I have an option that says "Open Terminal Here". It would be really helpful. Status of B1/B2 visa after citizenship change? I have a valid B1/B2 visa valid to US till March 2019 on Indian passport, I changed my citizenship to Australian. Is my B1/B2 visa on Indian passport valid? How did the transdimensional Edo god (Edo lord) come to be the overseer of the Edo? The isomorphism $\mathbb{Z}[i]/(a+bi) \cong \Bbb Z/(a^2+b^2)\Bbb Z$ is , when the integers $a$ and $b$ are coprime. But what happens when they are not coprime, say $(a,b)=d&gt;1$?      — For instance if $p$ is prime (which is not coprime with $0$) then $$\mathbb{Z}[i]/(p) \cong \mathbb{F}_p[X]/(X^2+1) \cong \begin{cases} \mathbb{F}_{p^2} &amp;\text{if } p \equiv 3 \pmod 4\\ \mathbb{F}_{p} \times \mathbb{F}_{p} &amp;\text{if } p \equiv 1 \pmod 4 \end{cases}$$ (because $-1$ is a square mod $p$ iff $(-1)^{(p-1)/2}=1$).  — More generally, if $n=p_1^{r_1} \cdots p_m^{r_m} \in \Bbb N$, then  each pair of integers $p_j^{r_j}$ are coprime, so that by CRT we get $$\mathbb{Z}[i]/(n) \cong \mathbb{Z}[i]/(p_1^{r_1}) \times \cdots \times \mathbb{Z}[i]/(p_m^{r_m})$$  I was not sure how to find the structure of $\mathbb{Z}[i]/(p^{r}) \cong (\Bbb Z/p^r \Bbb Z)[X] \,/\, (X^2+1)$ when $p$ is prime and $r&gt;1$.  — Even more generally, in order to determine the structure of $\mathbb{Z}[i]/(a+bi)$ with $a+bi=d(x+iy)$ and $(x,y)=1$, we could try to use the CRT, provided that $d$ is coprime with $x+iy$ in $\Bbb Z[i]$. But this is not always true: for $d=13$ and $x+iy=2+3i$, we can't find Gauss integers $u$ and $v$ such that $du + (x+iy)v=1$, because this would mean that $(2+3i)[(2-3i)u+v]=1$, i.e. $2+3i$ is a unit in $\Bbb Z[i]$ which is not because its norm is $13 \neq ±1$.  — I was not able to go further. I recall that my general question is to known what $\mathbb{Z}[i]/(a+bi)$ is isomorphic to, when $a$ and $b$ are integers which are not coprime (for instance $a=p^r,b=0$ or $d=(a,b) = a^2+b^2&gt;1$).  Thank you for your help! Light emission from the vicinity of a black hole The photograph of the black hole, at the centre of galaxy M87, is now a part of human history. We are told that the red-colour is caused by hot gas, matter &amp; radiation around the "edge", the Event Horizon. Given the power of the gravitational forces emanating from black hole, why aren't these three things drawn into the abyss? If light is bent/ drawn into the BH, how does this red image arise? The logic, here, would be that a body, on the Event Horizon, is immune from the gravity--which sounds pretty fatuous? How to switch from Resident visa to Tourist visa status in the Schengen area? I have a 1-year residence permit from one Schengen country that is now expiring. Upon its expiration, I would like to get my 90/180 days validity as a tourist to stay, or return here as soon as possible.  I understand that the tourist short-stay scheme is based on the 90/180 days "counter". But what happens if my previous stay was not tourism but residence (as searching year). Wouldn't that mean that I can quickly exit and re-enter the Schengen area to activate my tourist stay?   Also, is there a way to change this purpose of stay without exiting the Schengen area? Where can I download Windows 8 legally, from Microsoft? Unable to set DYLD_FALLBACK_LIBRARY_PATH in shell on OSX 10.11.1 I am looking for a way to replace a string in a file with a string that contains a slash by using sed.  connect="192.168.100.61/foo" srcText="foo.bar=XPLACEHOLDERX" echo $srcText | sed "s/XPLACEHOLDERX/$connect"   The result is:  sed: -e Expression #1, Character 32: Unknown option for `s' Do you ever center AND standardize variables in multiple regression? It seems as if standardization would automatically center variables...is this true? Turning vector grid into individual shapefiles using QGIS? I am using QGIS and I created a vector grid on a crop field in order to cut it into plots. I want to save each grid cell into individual polygon shapefiles automatically.  Here is an example of a vector grid I would like to split into 117 shapefiles:    Eventually, I did it manually with the selection tool and "Save as" but it is really time-consuming when there are more than 100 plots to save.    Is there any way to do it faster and more automatically?  Each plot as an attribute named "Plot" that can discriminate against them (basically being id + 1). It's the attribute used here to label them. Was it just coincidence that Tahir Mahmood went on stage? Is acceleration due to gravity constant? I have my bachelors degree in engineering science: computer science, option electrotechnic. I have a good understanding of basic mechanics and dynamics, calculus (differential equations).  The books I'm now having a look at are:       What book do you recommend for studying fluid dynamics on my own and why? What is the most efficient way to make money? What are some of the most efficient ways to make money?   Based on:    time initial investment required progress (in the game) special equipment/gear I'd like to use JavaScript to calculate the width of a string. Is this possible without having to use a monospace typeface?  If it's not built-in, my only idea is to create a table of widths for each character, but this is pretty unreasonable especially supporting  and different type sizes (and all browsers for that matter). Who are the Steam Mascots? So with the Steam Summer Sale in full swing, I've finally taken notice of the Steam Mascots.  Judging by the latest background, the black one, at least, has a name: Cyl.  Do the other two have names as well? Are there only these three?   What's their story? Cann I use a 19.5V 4.62A laptop charger for 19V 4.74A laptop? Sequence of differentiable functions Let $f_n$ be a sequence of differentaible functions on $[0,1]$ to $\mathbb{R}$ converging uniformly to a function $f$ on $[0,1]$, Then    $f$ is differentiable and Riemann integrable there $f$ is uniformly continuous and R-integrable $f$ is continuous, need not be differentiable on $(0,1)$ and need not be R-integrable on $ [0,1]$, $f$ need not be continuous.   Well I think 2 is only correct statement  as every $f_n$ are differentiable on $[0,1]$ hence uniformly contnous, and as they converge uniformly to $f$ on $[0,1]$ so $f$ is uniformly continuous and every continuous function is rieman integrable..Am I correct?