I want to know how to type the middle symbol below. I tried detexify but it didn't get what I wanted.
Browsing through a copy of Counterexamples in Analysis (Gelbaum  &amp; Olmsted), I'm quite enjoying the typeface used for 'script' letters (see links to examples below); visually it's somewhere between what I'd now call calligraphic and fraktur, and semantically it's used where now we'd use mathcal, mathfrak or mathbb.  I was therefore procrastinatiously looking for a LaTeX-usable font to include these characters, but couldn't seem to find any. I'm certain they're not unique to this text or publisher, so figured my lack of success was probably more to do with searching with the wrong keywords. If anyone has any ideas I'd be grateful.
How to change the chapter number to display as text (One, Two, ...)? In LaTeX, how do I change the chapter number to display as text? eg:  CHAPTER ONE not CHAPTER 1;  CHAPTER THIRTEEN not CHAPTER 13. Is there any way to check whether a file is locked without using a try/catch block?    Right now, the only way I know of is to just open the file and catch any System.IO.IOException. I made changes to iptables config file in /etc/iptables/filter in Ubuntu and want to reload them. I read the man page and also googled but couldn't find the information. Any help will be appreciated. Here's an example of a short conversation between me and a native speaker via text messages:  A: I'm so exited for this app B: Yeah, me too A: We start tomorrow B: OK   Shouldn't it be "We are starting tomorrow"?! Prove：$x^d-1 \mid x^n-1$ iff $d \mid n$. Consider the polynomial ring $F\left[x\right]$ over a field $F$. Let $d$ and $n$ be two nonnegative integers. Prove：$x^d-1 \mid x^n-1$ iff $d \mid n$.  my tries:  necessity, Let $n=d t+r$, $0\le r&lt;d$ since $x^d-1 \mid x^n-1$, so, $x^n-1=\left(x^d-1\right)\left(x^{\text{dt}+r-d}+\dots+1\right)$... so,,, to prove $r=0$? I don't know, and I can't go on. How to do it. increasing impedance of headphones I have headphones with differential input and impedance of 8 ohms. I need to drive this headphone with some DAC with built in headphone driver (Currently I have chosen ADAU1772). DAC's datasheet mentions that the minimum impedance of headphones it supports is 16 ohms. Can I increase impedance of my headphones so that I can drive them through this chip? What will happen if I drive this 8 ohm headphone through a chip supporting minimum impedance of 16 Ohms? How do I root my Android device? This is a common question asked by those who want to root their phones. How exactly do I root my Android device? Are there risks involved? In  Deathly Hallows, when Harry, Ron, and Hermione are at No. 12, Grimmauld Place, Harry summons Kreacher from the kitchens at Hogwarts where the elf has been working on Harry’s orders given a year previously.  When the trio’s heist in the Ministry of Magic ends with Hermione inadvertently bringing Yaxley inside the perimeter of the Fidelius charm that protects Grimmauld Place, the trio leg it and dare not return there for fear that it’s now crawling with Death Eaters.  Before they leave for the Ministry in the morning, Kreacher is talking about making a stew or pot roast or something for dinner. After the trio go on the run and camp out in the tent, Harry thinks of poor Kreacher preparing a dinner they’ll never return to eat, but they dare not summon him lest a Death Eater tag along (like how Dobby ‘tagged along’ with Kreacher when Harry called him to have him follow Draco in Half-Blood Prince).  The next time we see Kreacher is during the Battle of Hogwarts where he leads the house-elves from the kitchen with battle-cries of “For Master! For Harry Potter!” (or something like that), so he’s clearly lost none of his new-found loyalty to Harry.  Harry is still Kreacher’s master throughout the book, and since he does not communicate at all with Kreacher after their escape from the doorstep, he cannot have ordered Kreacher to return to Hogwarts to work there again.  We know that house-elves can go against their masters’ wishes, but this usually entails them punishing themselves rather brutally, and Kreacher does not seem to have been constantly injuring himself for the better part of a year at Hogwarts.  So when and how does Kreacher leave his master’s house without orders and return to Hogwarts? Java Enum definition I thought I understood Java generics pretty well, but then I came across the following in java.lang.Enum:  class Enum&lt;E extends Enum&lt;E&gt;&gt;   Could someone explain how to interpret this type parameter? Bonus points for providing other examples of where a similar type parameter could be used. How force Chrome to use google.com search engine without https Is there way to move one vertex and make another move with it proportionally? I'll try to explain in this gif. I am doing this manually in 2 steps - rotate, scale. And I select all vertexes. Is there instrument rotate them in one step or can I move one and make other move too? I have an area which is divided into several zones the borders of which I have defined as separate layers.  The layers are defined by sql queries on a postgis table of line segments joined with a table that says which segments are part of which zone boundaries.  What I want to do is produce a set of maps where each map is a zoom to layer extent for each zone and which has standard header, legend and scale (which will preferably vary with the zone but could be fixed across all maps).  My first attempt was to get a new composer for each map -- that worked but was rather tedious.  Next I tried producing one map and printing it and then deleting the map frame and going into qgis to zoom to the next layer extent and make the boundary visible then hopping back into the composer to load it in.  This worked more or less.  Map was fine, legend was OK because it was the same for all the maps and the zone name was easy to edit but the scale needed to be deleted and set up again for each map.  Next I looked at Atlas Generation.  The manual seems to assume that you know how it works and all you need is a reminder about the details (like so many software manuals ;)  It seems to assume that you have something that you are iterating over but I can't see how to make it work -- there is nothing to iterate over to get the layers.  Any suggestions welcome!!  :)  Russell How does Newtonian mechanics explain why orbiting objects do not fall to the object they are orbiting? The force of gravity is constantly being applied to an orbiting object.  And therefore the object is constantly accelerating.  Why doesn't gravity eventually "win" over the object's momentum, like a force such as friction eventually slows down a car that runs out of gas?  I understand (I think) how relativity explains it, but how does Newtonian mechanics explain it? Best practice: card expiry date on checkout Tag synonym suggestion textbox is overlapped by "Suggest" button Close Lightning Modal by clicking anywhere outside of it Just wondering whether this is possible? i.e. once a modal is open, close it by clicking anywhere on the grey backdrop?  I've tried invoking my custom close-modal function via: - Adding onclick to the slds-backdrop div - Adding onblur to the slds-modal__container div - Adding onclick to the slds-modal (just wanted to see whether this would work)  None of these seem to work. I woke up this morning to find that I suffered a massive drop in reputation points across the network because lots of users had been removed.  What happened to those users? Was there a database cleanup? For random variable $X$ that follows some distribution, $f(x)$ is the probability density function of that distribution if and only if $$\mathbb{E}[\phi(X)] = \int_{-\infty}^\infty \phi(x) f(x)dx$$ for all functions $\phi$.  Context: My professor used this in lecture to demonstrate a way to find the distribution of $cX$ given random variable $X$ that follows a specific distribution.   What is the name of this theorem? Have I missed any qualifications/caveats? I am in particular curious about whether "for all functions" is correct. My professor mentioned "positive, bounded, deterministic functions," but I am not sure what he meant by that. Where can I find a proof of this theorem? Travelling from India to canada via Dubai and London. Do I need a transit visa Arithmetic progression topology