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π Approximator

What is this?

This is a simple estimator for π using randomness! It is possible to approximate π with random number generation and simple shapes, to accuracy scaling with the amount of points n set.

How does this work?

Consider a box with sides of length 2 (unitless), and a unit circle (radius of 1) inside of the box such that the edges of the circle touch the inside edges of the box. We then randomly place n points inside of this box, and count the amount of points inside of the circle. We do this using the condition x**2 + y**2 < 1 as our circle has radius 1. The points that satisfy this condition will, as n->inf, draw out our circle.
If we think about the areas of our two shapes we have (2r)**2 for the box, and π r**2 for the circle. Taking the ratio of these leaves us with π / 4; we can treat each random point as area-like (we are taking ratio so any consequences are lost), and do this ratio as such: n_circle / n_total giving us π / 4.

Estimator