augustoqueiroz / findingpi

A repo for dumb interesting ways of finding Pi

Finding Pi

This repo was created inspired by Matt Parker's weird and awesome passion for finding pi in interesting creative ways.

Ways of finding Pi

1. Co-prime Random Numbers

This first method is taken directly from one of Matt's videos. Basically the idea is to find pi experimentally through the probability that given two random numbers they'll be co-prime. This can be proven to be 6/(pi^2). You can see the proof given by Matt on his video.

2. Monte Carlo

Imagine you have a square with a side of length L, and imagine that you have a circle inscribed in that square (therefore of radis L/2). What is the chance that a randomly chosen point inside that square is also inside the circle? pi/4. To find pi we can experimentally approximate that probability and then multiply it by 4.

3. Buffon's Needle

If you throw many needles at a ruled paper, you can try and estimate PI by counting how many of those needles crossed a line. The needle's length must be no more than the length between the lines of the paper.