In my trigger I want to prevent something happening if the total number of records in a transaction is 500 (because it's breaking). Trigger.size returns the number of records in that current 'chunk', so if I process 500 records in total it returns 200, 200, 100. Is there any method to allow me to...

If two complex projective manifolds are homotopy equivalent are they homeomorphic?

I am a graduate student in a US chemistry department and found a class (mechanical engineering) that would be somewhat helpful for my research but is out of my discipline. I'm not familiar with a lot of the methods used and so I was considering emailing the professor to see if it would be possib...

I've started learning Python recently and I don't understand why Python behaves like this: >>> "OK" 'OK' >>> """OK""" 'OK' >>> "not Ok' File "<stdin>", line 1 "not Ok' ^ SyntaxError: EOL while scanning string literal >>> "not OK""" 'not OK' Why doesn't it give an error for the l...

inspired by Are these double stops playable on violin? : I have never had the opportunity to play a fretless string instrument. When writing music for violins or other string instruments, what rules can I follow to ensure that I don't write double stops that are impossible/impractical, whether in...

I have a table containing the date in unix time and a separate milliseconds field. I now try to create a date from the two fields for later calculation (e.g. filtering on a time range). After adding the milliseconds to the date created via ... dateadd(S, [timestamp_s], '1970-01-01') by adding a...

This is just an idea I have been toying with. Taking Earth as an example with 7 days in a week, my idea would that there would be 7 moons in orbit around the planet. They would not necessarily share the same orbit, but they would orbit in such a way that only one is visible each night. That way e...

What is the best way to typeset the vertical line tone marking used in Pe̍h-ōe-jī using LaTeX? I would like to avoid requiring the use of specialized fonts or XeTeX/LuaTeX. The diacritic appears similar to a straight single quote that appears above a letter. Here is a sample of the diacritic type...

The 18th level feature of the pyromancer sourcerous origin from Plane Shift: Kaladesh says: any spell or effect you create ignores resistance to fire damage and treats immunity to fire damage as resistance to fire damage. The Elemental Adept (Fire) feat says: Spells you cast ignore resistance ...

Trying to set up a lamp development environment by following this guide: https://www.linode.com/docs/web-servers/lamp/how-to-install-a-lamp-stack-on-ubuntu-18-04/. Trouble starts at the virtual hosts section, step #4, I subbed out the example.com to deckdev.local, so the final command should be s...

when embedding my tikz images into different types of document-classes, I experience some very annoying differences. I have provided the following MWE: \documentclass[ ]{book} %]{scrbook} \usepackage{tikz} \begin{document} \begin{tikzpicture} \draw [rounded corner...

I don't really know if the question is suitable to be submitted here or in the Physics StackExchange. The problem is I don't quite understand this sentence from "Practical Electronics for Inventors" Book, p.377 When a load is attached to the secondary, the secondary current sets up a magnetic fi...

I'd like to completely delete an address from bitcoin-core, in such a way that someone who obtains all the data on my computer could not find out I ever used that address. Is it enough to delete wallet.dat? Is there a less destructive way?

Question Has there been a proof that shows there does not exist a Fixed-Parameter Tractable algorithm (FPT) for a specific NP-hard problem? Doubt It might be a trivial question as it perhaps is possible to always "stuff" the entire problem within the $f(k_1,k_2,..,k_m)$ part of the $f(k_1,k_2,.....

I seem to remember some writer doing variations on the 'throw the first stone' verses with Jesus actually throwing the stone in one of them. Unfortunately, I can't remember about why that comes up. It feels like Zelazny to me, but I don't see anything in my collection that it would be in. Does...

In the book, there is such a proposition: Proposition 4.4.5: For every rational number $\epsilon>0$, there exists a non-negative rational number $x$ such that $x^2<2<(x+\epsilon)^2$. Can I prove it as follows: Let $\epsilon>0$ be rational. Suppose for the sake of contradiction that there is no...

This is a canonical question and answer developed by the community to help address common questions. If you've been directed here, or your question has been closed as a duplicate, please look through the resources here and use them to shape more specific questions. To browse all canonical questio...

I am relatively new to web development I already have built some websites and currently I am tackling a large project. I am creating a website for my MC-Server. For that, I am working with media queries to ensure that the website looks good on all sorts of devices. BUT: I figured out, that there ...

As the title says, the Morse potential (https://en.wikipedia.org/wiki/Morse_potential) is an exactly solvable model in quantum mechanics, just like the quantum harmonic oscillator. Extensions of it are used in modeling molecular vibrational states to great success as far as I know. However, in so...

Problem I am locked in a room with no windows and I need to tell if the room is moving, I only have a lamp. According to my professor I cannot tell if the room is moving because of the Special Relativity Theory. My thought What if the room moves to a speed very close to the speed of the light and...

An interesting question arose elsewhere. Suppose you break out a "New, Old Stock" item. It is UL-approved and has UL-approved instructions. The instructions say to do X. However, since the item was UL-approved, NEC has changed. Doing X is now explicitly forbidden, and you must do Y. Which one ...

From Finnegan's Wake, What is the meaning of this word? In context: The fall (bababadalgharaghtakamminarronnkonnbronntonnerronntuonnthunntrovarrhounawnskawntoohoohoordenenthur- nuk!) of a once wallstrait oldparr is retaled early in bed and later on life down through all christian minstrelsy. The...

I have a Shimano Acera that hits the spokes in first gear (largest rear sprocket.) I found three screws on the derailleur Which one should I turn, in which direction? The bike (Specialized Sirius 2.0) is brand new, by the way, I thought I would fix it myself, as dealer service seems very busy atm...

SE.SE has a question about the historically first hierarchical file system (also a similar local question), but what was the first OS with a file system in general? That is, what OS was the first to abstract the external storage away from physical volumes at the OS level, even by pre-allocated fi...

Question: Assign the R/S configurations to the chiral carbons of this molecule: My Solution I first started out by numbering the carbons. The one at the top would be 1 and the bottom chiral carbon would be 3. Next, According to CIP rules, I have included the phantom atoms by replacing the doub...

The case is a de facto promotion of religion by a local municipality. A private citizen has placed a religiously promotive flyer on the notices board at the department of a local municipality. The board is enclosed by a locked, plexiglass window, and it is to the outside of this window the flyer ...

I'm trying to find integer positive solutions to the equation: $$ 2 (r^2 - r) = t^2 - t $$ So far I've been giving "test" values to t, say $t = 20$, and then solving the quadratic equation with substituted $t$. If the resulting value of $r$ is a natural number, then I have a solution. If not, I j...

The Pyromancer sorcerous origin from Plane Shift: Kaladesh has a feature called Fiery Soul: At 18th level, you gain immunity to fire damage. In addition, any spell or effect you create ignores resistance to fire damage and treats immunity to fire damage as resistance to fire damage. This abilit...

I am a Korean citizen, currently in Greece on a tourist visa. As many of you might know, as a Korean, I don't actually need to apply for the Schengen visa but it's a stamp on arrival for 90 days of stay (out of 180 days). My partner (German) and I are planning to get married in Denmark in the com...

I'm reading Soundrarajan's https://arxiv.org/pdf/0705.0723.pdf, and on page 5, one has $$\sum_{n\leq x} \frac{\Lambda(n)}{n^z} \log (x/n) = -\frac{\zeta'}{\zeta}(z)\log x - \Big(\frac{\zeta'}{\zeta}(z) \Big) -\sum_{\rho} \frac{x^{\rho-z}}{(\rho-z)^2} + O(1/T),$$ where $\Lambda$ denotes the von Ma...

Let $D: I \to \mathcal C$ be a diagram, and suppose we have a colimit decomposition $I = \varinjlim_{j \in J} I_j$ in $Cat$. Then under certain conditions, we can decompose the colimit of $D$ as $\varinjlim_{i \in I} D_i = \varinjlim_{j \in J} \varinjlim_{i \in I_j} D_i$. But I've never seen gene...

I would like to write some software, in my free time, and release it under GPLv3. As I understand it, this would imply that any software that uses that code must also abide by the terms of GPLv3. I work on a project which is closed source, and while I would like it to be free software, I certainl...

I’m writing a story where alien races are in constant communication with humans, but I don’t want it to be awkward or have to use language tags like “...he said in x language.” Maybe I could have a conspiracy event where the evolutions of all the languages converge at the point of first contact, ...

I play Sicilian (mainly Najdorf) against e4. Sometimes (in anti-Sicilian or Sicilian openings) I end up with exchanging everything except 6 pawns. So it becomes a 4-2 pawn (4 on the kingside) versus 3-3 end game. I am the side with 4-2 and most likely a6-b5 being the two. I remember losing a few ...

According to this FAA ruling a pilot can operate an aircraft under an IFR flight plan even if the aircraft is not IFR certified, provided the operation occurs in VMC. What the ruling doesn't differentiate is whether the pilot doing that operation must be an IFR rated pilot (the ruling is with re...

I have a 4 1/2” diamond cup grinding wheel installed to my angle grinder. I screwed it on all the way, but there is no room for the locking nut. I called DeWalt and they said since it is a screw-on wheel, i do not need the locking device, but that kinda worries me. Is this safe without a locking ...

I am making a NSFW game and splitting the profits 50-50 with someone I've met online. I learned that that is enough to form a general partnership, and now I will have to file a form 1065. Both of us want to remain anonymous and don't want to even tell each other each other's names. All of our wo...

This is exercise 3.1.31. from the book Computer Science An Interdisciplinary Approach by Sedgewick & Wayne: Write a filter KamasutraCipher that takes two strings as command-line argument (the key strings), then reads strings (separated by whitespace) from standard input, substitutes for each let...

A week ago, I was forced to once again reinstall Windows 10. Now I have "2004". I don't know if it was the new version of Windows 10, or the new version of foobar2000, or a combination of both, but now, every time I press my "mute/unmute system sound" button, Windows 10 shows not just the little ...

The 8 queen's puzzle is a well-known puzzle involving placing 8 queens on a chess board so that no queen attacks another queen, and it is more or less obvious that 8 is the maximum number of queens that can populate a chessboard so that no queens are attacking each other. But what if we use knigh...

I am games mastering for the tomb of annihilation and my group will be exploring an abandoned mine near Fort Beluarian, so I wanted to create a level mini dungeon for a party of five people. Choosing the monsters randomly I put a Gibbering Mouther in the dungeon, however, reading its bite attack ...

Forgive me for this noobish question (still learning ropes of blender) but I'm playing with some of the lights properties, and was wondering what this line is and if there is a way to adjust the length of it. I've circled the line in red in the photo. Currently it surpasses my landscape, and it's...

You have not been the best person during your time on Earth. Your judgement is as such: uryy But what does this mean?

Reading my calculus notes I found this lemma: Suppose that $\lim\limits_{x \to a} f(x)=l$ and that $g(x)=f(x)$ for $0<|x-a|<\delta_0$ (for some $\delta_0$). Then $\lim\limits_{x \to a} g(x)=l$ What exactly does this lemma mean? I'm having trouble understanding it.

Suppose I own a greataxe, and a blacksmith owes me a favour. The Smith knows how to craft silvered weapons, and has agreed to do the work as a favour if I provide the raw silver. The rules on silvered weapons state: You can silver a single weapon or ten pieces of ammunition for 100 gp. This cost...

I have searched, and seen some type of questions related to this. However, I have seen no sources. I figured I would ask: does anyone know of any sources for this? Why do we do it?

We have a set of N coins that are all placed in a circle. They all have "Tails" as their face up side. The coins are all distinct and have numbers (1,2,3...N) written on them. In each move, we flip any 3 consecutive coins. That is, consider: H H H T T If I decide to flip the coins 3,4 and 5 then ...

Except for command blocks, structure voids and all other unobtainable blocks, which block is the hardest block to obtain? For example: an emerald block is hard to get, as emerald ores are rare.

A server that is part of a SQL 2017 Always on availability group (BAG) I have noticed an increase of these messages. I understand these are messages that appear in the log as standard since 2012 (trace flag prior to 2012) but over the last 2 days they are appearing every few minutes, there are no...

君の目が貫いた　僕の胸を真っ直ぐ This is one of the lines in a song I recently heard. I was confused why the particle "wo" is in between the direct object and an adverb that modifies the verb, 貫いた. Can anyone explain what is going on in the sentence? Does it only apply on Written Japanese? Thanks in advance! ^...

What are the most important parts to consciousness according to philosophers? I am guessing memory plays a crucial parts, but I am guessing there might be elements to consciousness that are more important to consciousness that were identified by philosophers, what are they?

Question: The sphere of radius a was filled with positive charge at uniform density $\rho$. Then a smaller sphere of radius $\frac{a}2$ was carved out, as shown in the figure, and left empty. What are the direction and magnitude of electric field at A? At B? How do I solve this question? The hin...

First, let me say that Shopify couldn't figure this out, nor people I tried to hire on Fiverr. My site seemingly, and for no apparent reason, got messed up on Google. My traffic went down to 0 and the culprit is Indexing. Google console suddenly says that my main domain's URL is not on Google. O...

Being new to perl and its versions, I thought it worked like R but OBVIOUSLY not. I had folder /usr/share/perl/5.26.1 folder and /usr/share/perl/5.26 folder both with same files so I deleted /usr/share/perl/5.26 folder. Everything was okay. When I enter perl -v I get This is perl 5, version 26...

Watching the recent SpaceX Starship tests got me to thinking: Could you actually make a rocket using grain as the propellant? Image from https://www.teslarati.com/spacex-starship-sn5-second-hop-plans/ Grain, especially dry grain is quite flammable, and grain explosions are a thing that can happe...

let elements: [(Int?, Int?)] = [(1, 2), (2, 1), (3, nil), (nil, 3), (5, 6), (6, 5)] let result = elements.filter { $0.0 != nil } as! [(Int, Int?)] Is there a more clean way to get partly non-optional type as a result? Without force-unwrapping... When we filtering out nils it's should be obvious ...

I'm looking at creating a simple backup routine, using standard Python, to backup my GeoPackages. The routine needs to be flexible enough to be able to backup the geopackage, whilst it is open (in read mode). Whilst I don't have a requirement for it to backup in write mode, I'm sure this will be ...

As shown in many threads here (this, this, ...), Ticks is a valid option of BarLegend. But it doesn't seem to work well in this simple MatrixPlot. Some ticks are just missing and 0.5 is obviously not at its right place (color). Note that I want custom ticks rather than automatic ones that can som...

The plus operator is not center aligned. Please help.

I'm displaying a file contents by using :pedit …the-file-path…, to then call popup_setoptions(…the-ID…,#{firstline:anumber}) in order to scroll the popup and highlight/show the desired part of the file. There's however one problem — the folds are closed by default and thus they hide the file cont...

I have an array of data in the below format let input = [ { time: "2020-7", tasks: [ { key: "p1", value: 15 }, { key: "p2", value: 13 }, ] }, { time: "2020-8", tasks: [ { key: "p1", value: 16 ...

Let $g(2n)$ be the number of representations of $2n=p+q$ with primes $p$ and $q$. Many people have asked whether $g(2n) \ge 2$ when $2n = p+q$ for some primes $p$ and $q$. That is, does $g(2n) \ge 1$ imply $g(2n) \ge 2$? From the famous Goldbach Comet, it looks probable although it was not yet pr...

I have already asked this question and no comment(s) received up to now. I am so curious to get feedback concerning the problem. Let $M$ be a vn Neumann subalgebra in $B(H)$. Let $f$ and $g$ be normal functionals on $B(H)$ and $M$ respectively. Suppose that $f_{|_{M}}=g$ i.e, the restriction o...

I am trying to understand working of MPPT charger for LiPo battery (3.7V nominal) and 6V 2W solar ‎panel so that I can select right charger for my project. After searching and reading lot of related material on the net, my understanding is that, while charging, in all light conditions, the voltag...

Engels (1880): The foundations of the exact natural sciences were, therefore, first worked out by the Greeks of the Alexandrian period, and later on, in the Middle Ages, by the Arabs. When was this "Alexandrian period"? The linked Marxists.org page says in a footnote: The Alexandrian period o...

On August 11, Russian president Vladimir Putin announced a new vaccine for COVID-19. Since then Russia's COVID charts have looked like this: Evidently the vaccine has had a weak-to-no effect on both the number of cases and the number of deaths. Why? The obvious answer is "because it doesn't work"...

I had to solve the next exercise: If $f,g:\mathbb{R}\to\mathbb{R}$ are functions that satisfy $\lim\limits_{x \to a} [3f(x)+g(x)]=1$ and$\lim\limits_{x \to a} [2f(x)-3g(x)]=8$ then find the limit $\lim\limits_{x \to a}\frac{f(x)}{g(x)}.$ This is what I did: Let $\lim\limits_{x \to a}f(x)=l$ an...

I would like to define the following command: \newcommand{\prob}[1]{\underset{#1}{\mathbb{P}} Often, parameter 1 remains unfilled. Is it the correct way to define this operator? I was also considering using the \limits command, but I don't have clues on how I can make it work.

So I have this sheet music by Coldplay, the title of the song is called Clocks and I am trying to understand the notes. My question is how do I know when a flat or sharp is supposed to be played? I wrote down the notes and what I have is D A G D A G D A for the first set. However, when I watch tu...

I am asked to review a paper for a fairly highly regarded conference. The paper presents some 'novel' algorithms to do a particular job, but it fails to mention any of the various related previous work which address the very same issue. Even if the algorithm is sound and their method is thorough ...

Let's consider this device I have built: It is essentially a power supply for a 24V DC motor. The power supply is switched on and off according to a proper control signal (which drives a relay) which is not important at the moment since it has always been put to ON while the device was working. ...

I would like to ask about the possibility of capturing coordinates for more than 1 object in QGIS. I used to use the coordinate capture plugin, but what is the problem there I have to collect coordinates one by one. Is there any way to collect coordinates i.e. for all points from the given layer ...

I found a sentence from a short story which goes: "他指了指墙上的画。“ I know that 指 means to point, by why is it repeated twice in the sentence? Any help would be appreciated. Thank you

Talk is cheap; show me the code. // equals to this.fellan = "window" var fellan = "window"; function f () { console.log(this.fellan) }; var a = { fellan: "object", fn: f }; a.fn(); // "object" --> fine (a).fn(); // "object" --> fine (1, a).fn(); // "object" --> fine (a.fn)();...

I'm quite familiar with loss functions in machine learning, but am struggling to connect them to loss functions in statistical decision theory [1]. In machine learning, a loss function is usually only considered at training time. It's a differentiable function of two variables, loss(true value, p...

My searches have lead nowhere on this one. I have a MeshRegion (say, a 2D manifold embedded in 3D) and would like to plot a function on it: such that the color of a point at (x,y,z) is determined by a function of the coordinates. I have found MeshCellStyle, which allows me to specify flat color p...

I'm looking for a story where a vastly superior alien civilization "invades" United Earth space but instead of attacking, they surrender, much to the surprise of the assembled Earth military and dignitaries who were expecting total war or annihilation. This is what I remember from the story: A me...

Question (previously asked here) You know there are 3 boys and an unknown number of girls in a nursery at a hospital. Then a woman gives birth a baby, but you do not know its gender, and it is placed in the nursery. Then a nurse comes in a picks up a baby and it is a boy. Given that the nurse pi...

I have bought a Samsung 27" Full HD (LC27R500FHNXZA) monitor and have connected my MacBook Pro 2016 (macOS 10.13 "High Sierra") to it via HDMI. This is the image I see: And this is the image I see on my own display: I still see individual pixels clearly. I tried to follow this guide to copy the...

One of my Facebook friends posted this sheet I was shocked by the quantity of clefs being used. Moreover, they aren't placed at the same vertical position (which I assume changes the reference points for the notes after that). Is it common practice to use that many different keys on different ve...

I'm trying to find a solution to the following differential equation: $$ \frac{d^2x}{dt^2}=-Axe^{-x^2/2} $$ Or better yet if I can find some function $\xi(x)$ such that $$ \frac{d^2\xi}{dt^2}=-B\xi. $$ Somehow, $x(t)$ is supposed to be periodic (how would I know that in general, or maybe it's jus...

I saw an explanation about Icon A5 Light Sport Airplane (LSA), it is said that according to FAA regulation, its stall speed NOT LESS than 45 miles per hour (mph) or around 39.1 knots or around 72 km per hour (kmph). Which is mean, its minimum speed is that 45 mph. I was curious that minimum speed...

In this question, we can clearly see the origin of 巨 is 矩, which is originally formed from 工 + 大 (corrupted into 矢). However, nowadays 巨 has lost the left hand side of 工, and so naturally the radical appears to be "匚". Some dictionaries list 巨 as having 工, and some as 匚 radical. For example, Hanp...

Why did India ban PUBG if it is a non-Chinese app? Wikipedia reads PUBG (PlayerUnknown's Battlegrounds) is Korean app.

When interviewing for a new job, how can I phrase a question to determine how hard I would be expected to work? For example, how can I find out about things such as unofficial small breaks? I really hate being in the same building all day (or same room all day) and highly value the chance to get ...

The gold standard is a monetary system where a country's currency or paper money has a value directly linked to gold. The U.S.A (United States of Amestris) operated on this standard, allowing the amestrian dollar to avoid inflation and making it the top reserve currency in the world. However, in ...

I'm reading up on graphic formats and noticed that I have several GeoTIFFs that are larger than the apparent limit on TIFF file size of 4 GB. Can someone explain what I am missing here? Do BigTIFFs have a different file extension?

I am a Spanish citizen and I would like to travel to the UK from Spain, Edinburgh more specifically. But currently, I would need to self-isolate for 14 days since the country is not on the list of exemptions since the 26 July. Spain (this does not apply to arrivals from 00:01 on 26 July 2020) I h...

Challenge Given a number x and a precision e, find the lowest positive integer q such that x can be approximated as a fraction p / q within precision e. In other words, find the lowest positive integer q such that there exists an integer p such that abs(x - p/q) < e. Input The pair (x, e) where ...

Mildred Gillars was convicted of treason September 10, 1948. As I understand it, first Amendment protects unpopular speech, but is confined and not unlimited. The classic example is that one can not yell "fire" in a crowded movie theatre and incite a panicked exodus. I imagine free speech as a ...

I have a shape with different city areas that contains the average building heights ("HHO-mean") in meters. Now I want to categorize the average bulding heights in a new column in five different categories (1-5). I tried the following: CASE WHEN "HHO_mean" > 5.7 THEN 1 WHEN "HHO_mean" > ...

SF Documentation states the following If a Bulk API request causes a trigger to fire multiple times for chunks of 200 records, governor limits are reset between these trigger invocations for the same HTTP request. Assuming an SObject has active apex trigger, an insert DML of 800 records via Bul...

I was doing an exercise of a past exam in which one of the things I had to do was calculating the nth power of a Jordan matrix $$J=\begin{pmatrix} 2 & 1 & 0 \\ 0 & 2 & 1 \\ 0 & 0 & 2 \end{pmatrix}$$ I started calculating until the 5th power but I couldn't guess the expression for the $a_{1,2}$, $...

I would like to add automatically a small after one macro content in math mode. The problem I have is that this space muste be gobbled if it is at the end of the formula. What is is the good concept to use to do that kind of stuff ? \documentclass[12pt,a4paper]{article} \newcommand\param[1]{\mat...

Large numbers have a nice space separator which I want to keep. But these gaps are annoying in small numbers and I want to get rid of them. Here's a MWE showing my issue: \documentclass[12pt,letterpaper,twoside]{book} \usepackage{lmodern} \usepackage{amsmath} \usepackage{siunitx} \begin{docume...

I will publish patent application and I want to share my invention with others right after that. I want to see if there will be any interest from investors. Are there any dangers associated with such a disclosure (as the priority date is granted already)?

Let $X$ be a finite connected pointed CW-complex and $H_{\ast}(\Omega X)$ the integral homology of the loop space on $X$. Are the homology groups $H_{n}(\Omega X)$ finitely generated abelian groups for any $n$ ? If the answer is negative, what are the sufficient conditions to impose on $\pi_{1}(X...

According to JNCIP study guide(page 156) from 2003, the Junos should advertise a prefix on lo0.0 interface to OSPF if the RID is not manually configured: JUNOS software automatically advertises a stub route to the interface from which the RID is obtained; therefore it is not actually necessary t...

https://youtu.be/ISEo-8k-6gg I'm trying to animate a treasure chest, so I moved the origin to an edge, and now I cant rotate it properly. I know you can do this, but I don't know how I might've messed it up.

I have a question regarding SSRs. I am working on redesigning a PCB for a medical device that needs to pass class B radiated emissions, therefore radiated EMI must be very low. We have a CPU fan running off 12 V (~890 mW) and I was going to try using a SSR to control its operation, due to the cos...

Per title. As I understand contempt, it's a setting in the eval function that adds a bonus for material remaining on the board. This makes the engine favor positions with more material (i.e. more complex, i.e. more scope to outplay the opponent). It is meant to make the engine avoid quick draws a...

We often see reactions such as these in textbooks to highlight how reaction mechanisms work: How are the radioactive substrates required for these mechanisms synthesized in the first place? There seems to be no easy way of just 'substituting' a radioactive atom in place of a non-radioactive one...

Suppose I have an Ubuntu machine and did sudo apt install docker.io. Did I just put a huge security hole in my machine that will allow anyone with terminal access to escalate into root? I ask that because I can mount any directory as a volume inside a container, escalate to root inside the contai...

Linear velocity vector is $\vec{v}$ and the distance vector is $\vec{r} $. How is it that angular velocity vector is $\vec{ω}$ = $\frac {\vec{r} × \vec{v}}{|\vec{r}|^2}$ The equation I am aware of is $\vec{v}$ $=$ $\vec{r}×\vec{ω}$. I tried taking a dot product on both sides, cross product etc ...

A social decision function (SDF) à la Sen (1970) is defined as a collective choice rule whose range is restricted to social preference relations which generate a choice function. From Gaertner (2009), a preference relation $R$ generates a choice function over a set $X$ if and only if $R$ is refle...

I am looking for a SABR model pricing engine in Python QuantLib setting. I do know that it exists in C++ version, but not sure if available in Python. Any suggestion/feedback with respect to Python source code will be greatly appreciated!. Thanks!

I have a CD4017 counter configured so that any of its outputs can be connected to the reset pin, I also have manual reset button connected to the reset pin, this switch is buffered by a schmitt trigger. The problem is that the schmitt trigger holds the reset pin low and any CD4017 output connecte...

Recently I have been investigating some history of the mathbb(mathematical blackboard bold) letters of AMS, which can be called by invoking amsfonts or amssymb package. By the content on page 35 of Handbook of Typography for the Mathematical Sciences, Donald Knuth does not like the mathbb lett...

Why does "Hominem unius libri timeo" use comparativus unius instead of positivus unum? Does it mean "I fear a man of one book (more)"? Or does that unius belong to hominem because it is accusativus+comparativus?

In the summer I bought an e-road-bike that has tubeless-ready rims. I wanted to change the tires to better ones, so I bought a pair of Continental GP 5000 (non-tubeless) 28mm tires, and installed them on to the rims. It was a very hard job! I even punctured one tube in the process. Yesterday, I f...

I have an ordered sequence of points along a closed directed planar contour with self-intersections. I need to find a continuous curve interpolating those points and plot it, with small arrowheads showing its direction (preferably, placed at equal intervals along the curve), and color-fill enclos...

I noticed my hood covers (the rubber one) are slipping up -- I pull them down, align with hoods, some time later again (when riding of course) -- they are up. It is really annoying. Granted I put my hands on them, and with the force it is expected in sense of the physics, but I would like them to...

Spheres of Power and its related splatbooks recently came under the valid books my RPG group is allowed to use. The system is quite something, and far different from anything I have ever used in Pathfinder. So far, I'm liking it quite a lot, and my group is having a blast building characters with...