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-// Copyright 2018 Developers of the Rand project.
-// Copyright 2013-2018 The Rust Project Developers.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-//! # Monte Carlo estimation of π
-//!
-//! Imagine that we have a square with sides of length 2 and a unit circle
-//! (radius = 1), both centered at the origin. The areas are:
-//!
-//! ```text
-//! area of circle = πr² = π * r * r = π
-//! area of square = 2² = 4
-//! ```
-//!
-//! The circle is entirely within the square, so if we sample many points
-//! randomly from the square, roughly π / 4 of them should be inside the circle.
-//!
-//! We can use the above fact to estimate the value of π: pick many points in
-//! the square at random, calculate the fraction that fall within the circle,
-//! and multiply this fraction by 4.
-
-#![cfg(feature = "std")]
-
-use rand::distributions::{Distribution, Uniform};
-
-fn main() {
- let range = Uniform::new(-1.0f64, 1.0);
- let mut rng = rand::thread_rng();
-
- let total = 1_000_000;
- let mut in_circle = 0;
-
- for _ in 0..total {
- let a = range.sample(&mut rng);
- let b = range.sample(&mut rng);
- if a*a + b*b <= 1.0 {
- in_circle += 1;
- }
- }
-
- // prints something close to 3.14159...
- println!("π is approximately {}", 4. * (in_circle as f64) / (total as f64));
-}