Here is another #RosettaCode entry, in a dialect of Lisp that annoys me a whole lot, with compilers whose error messages make #ATS error messages look easy, but which I insist on using for these tasks, just the same:
I did some #math this time. It’s a catenary (the curve of a loosely hanging rope) made by drawing lines perpendicular to a tractrix. (The tractrix itself is not depicted.)
Born #onthisday 117 years ago, Kurt Gödel was an Austrian mathematician and philosopher. Gödel discovered the “Incompleteness Theorem”, which essentially states that there will always be theorems in mathematics that are impossible to prove. Gödel''s discovery of the Incompleteness Theorems effectively drove a stake though the heart of Hilbert's Program [1] (or at least badly damaged it; see Hilbert's Second Problem [2]).
In 1949 Gödel demonstrated the existence of solutions to Einstein's field equations in General Relativity which involve "rotating universes" and featured closed timeline curves which allow for time travel to the past. Gödel's solutions are known as the Gödel metric and are an exact solution of the Einstein field equations [3].
Along with Aristotle, Alfred Tarski and Gottlob Frege, Gödel is considered to be one of the most significant logicians in history and had an immense effect upon scientific and philosophical thinking in the 20th century (and beyond).
Someone on mse asked a cute question last night. I answered it, but had a kind of weird experience doing so, and I'm curious if other people will have a similar experience.
The #puzzle isn't so hard, so let me leave it here for a day so that people can have a chance to try it themselves. Then I'd love to use it to start a conversation about two approaches to problem solving in #math
Please post solutions as a reply to this, but put them in cw tags so that people can go spoiler-free if they want to! I'll @ everyone who replied when I post the followup sometime soon ^_^.
You and your friend play a game. Your friend gets to color each point on the unit circle either red or blue (she has very fine-tipped crayons) and you have to try and find 3 points on an equilateral triangle which get the same color.
You win if you can find such a triangle, and your friend wins if her coloring is able to stump you.
Can you always win? If not, how should your friend color the points to stop you from winning?
Any #stats or #math nerds out there want to offer me an opinion? One of my security programmes that I run will be tracking time-to-decision (typically measured in calendar days). We do between 50 and 125 decisions in a year, so there are only 5-10 data points in a typical month. As you can imagine, with any sort of human approval process, there will be outliers where things will go very quickly ("no way in hell") and some that will go very slowly.
I want to report on time-to-decision and I want to blunt the impact of outliers on our statistics. If there's one decision that takes 6 months and the others take a couple weeks, I don't want the one outlier making us look bad. The math question:
I was gonna use a trimmed mean, but reading about Winsorised means is also interesting. I was assuming I'd use a trimmed mean excluding the bottom 5% and top 5% and then report an average of the remaining 90%.
Anybody have better ideas? Anybody with opinions on trimmed v winsorised means?
#puzzle#math
Cette question a été posée par un enseignant à des élèves âgés de 8-9 ans. Vous pouvez la trouver bien challenging pour cet âge, et je serais d'accord avec vous.
Quel est le nombre manquant ? Quelle est la règle ?
Merci de répondre en mode CW (expliquez) et de partager pour plus de participants.
I went to #mathsjam in London a few times back in 2014 (has it really been so long?) I guess it's how I found out about mathstodon really, through following @ColinTheMathmo and others. I've been thinking it would be nice to organise mathsjam here in Plzeň for a while but I was busy and a little nervous about it. I finally decided to go for it, next month will be the first Plzeň mathsjam! Wish me luck :) #math
I have always struggled with math (too many things to hold in my head at one time) and have had to rely a lot on just rote memorization, which... at best only gets you so far, and at worst is not a fun process.
average person creates 3 spam accounts a year" factoid actualy just statistical error. average person makes 0 spam accounts per year. Gambling Website Georg who lives in cave & creates over 10,000 spam accounts each day, is an outlier adn should not have been counted
I keep my accounts in #LibreOffice, and when I start the year, I reset all the values to 0.
I have one cell which calculates a percentage. When I set all cells to 0, it throws a Divide By Zero error.
Is this correct? Surely the only number you can actually divide by zero is zero? Or is dividing zero by zero also mathematically/programmatically incorrect?
#énigme#puzzle#logique#logic#math
Les enfants peuvent résoudre ce casse-tête en 5 minutes, mais les adultes prennent 60 minutes environ.
Trouvez le nombre manquant (voir Figure).
Répondez en mode CW, et indiquez le temps passé chronométré.⏱️
I'm Tonya Marie, a mid-50s trans woman originally from Texas but now safely ensconced in Seattle. I'm a semi-retired #math teacher and occasional coder, but my passion is being a housewife for my loving wife.
Reading a book on Category Theory is rewiring my brain. I was workshopping all day today and I saw surjections everywhere and started talking about the pullback of X.