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Diffstat (limited to 'rand/rand_distr/src/unit_disc.rs')
-rw-r--r-- | rand/rand_distr/src/unit_disc.rs | 66 |
1 files changed, 0 insertions, 66 deletions
diff --git a/rand/rand_distr/src/unit_disc.rs b/rand/rand_distr/src/unit_disc.rs deleted file mode 100644 index 97abc2f..0000000 --- a/rand/rand_distr/src/unit_disc.rs +++ /dev/null @@ -1,66 +0,0 @@ -// Copyright 2019 Developers of the Rand project. -// -// 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. - -use rand::Rng; -use crate::{Distribution, Uniform, uniform::SampleUniform}; -use crate::utils::Float; - -/// Samples uniformly from the unit disc in two dimensions. -/// -/// Implemented via rejection sampling. -/// -/// -/// # Example -/// -/// ``` -/// use rand_distr::{UnitDisc, Distribution}; -/// -/// let v: [f64; 2] = UnitDisc.sample(&mut rand::thread_rng()); -/// println!("{:?} is from the unit Disc.", v) -/// ``` -#[derive(Clone, Copy, Debug)] -pub struct UnitDisc; - -impl<N: Float + SampleUniform> Distribution<[N; 2]> for UnitDisc { - #[inline] - fn sample<R: Rng + ?Sized>(&self, rng: &mut R) -> [N; 2] { - let uniform = Uniform::new(N::from(-1.), N::from(1.)); - let mut x1; - let mut x2; - loop { - x1 = uniform.sample(rng); - x2 = uniform.sample(rng); - if x1*x1 + x2*x2 <= N::from(1.) { - break; - } - } - [x1, x2] - } -} - -#[cfg(test)] -mod tests { - use crate::Distribution; - use super::UnitDisc; - - #[test] - fn value_stability() { - let mut rng = crate::test::rng(2); - let expected = [ - [0.018035709265959987, -0.4348771383120438], - [-0.07982762085055706, 0.7765329819820659], - [0.21450745997299503, 0.7398636984333291] - ]; - let samples: [[f64; 2]; 3] = [ - UnitDisc.sample(&mut rng), - UnitDisc.sample(&mut rng), - UnitDisc.sample(&mut rng), - ]; - assert_eq!(samples, expected); - } -} |