From 41aaa3c0c616b4b4c7702b5101d26ec3e1de083f Mon Sep 17 00:00:00 2001 From: Vinzent Steinberg Date: Tue, 24 Jul 2018 18:45:08 +0200 Subject: [PATCH] Add uniformity test for unit sphere and circle --- Cargo.toml | 2 ++ tests/uniformity.rs | 57 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 59 insertions(+) create mode 100644 tests/uniformity.rs diff --git a/Cargo.toml b/Cargo.toml index c44a4d62f0a..fcbe894f37e 100644 --- a/Cargo.toml +++ b/Cargo.toml @@ -58,6 +58,8 @@ wasm-bindgen = { version = "0.2.12", optional = true } # This is for testing serde, unfortunately we can't specify feature-gated dev # deps yet, see: https://github.com/rust-lang/cargo/issues/1596 bincode = "1.0" +# This has a histogram implementation used for testing uniformity. +average = "0.9.1" [package.metadata.docs.rs] all-features = true diff --git a/tests/uniformity.rs b/tests/uniformity.rs new file mode 100644 index 00000000000..0a6244ef82a --- /dev/null +++ b/tests/uniformity.rs @@ -0,0 +1,57 @@ +#[macro_use] +extern crate average; +extern crate rand; + +use std as core; +use rand::FromEntropy; +use rand::distributions::Distribution; +use average::Histogram; + +const N_BINS: usize = 100; +const N_SAMPLES: u32 = 1_000_000; +const TOL: f64 = 1e-3; +define_histogram!(hist, 100); +use hist::Histogram as Histogram100; + +#[test] +fn unit_sphere() { + const N_DIM: usize = 3; + let h = Histogram100::with_const_width(-1., 1.); + let mut histograms = [h.clone(), h.clone(), h]; + let dist = rand::distributions::UnitSphereSurface::new(); + let mut rng = rand::rngs::SmallRng::from_entropy(); + for _ in 0..N_SAMPLES { + let v = dist.sample(&mut rng); + for i in 0..N_DIM { + histograms[i].add(v[i]).map_err( + |e| { println!("v: {}", v[i]); e } + ).unwrap(); + } + } + for h in &histograms { + let sum: u64 = h.bins().iter().sum(); + println!("{:?}", h); + for &b in h.bins() { + let p = (b as f64) / (sum as f64); + assert!((p - 1.0 / (N_BINS as f64)).abs() < TOL, "{}", p); + } + } +} + +#[test] +fn unit_circle() { + use ::std::f64::consts::PI; + let mut h = Histogram100::with_const_width(-PI, PI); + let dist = rand::distributions::UnitCircle::new(); + let mut rng = rand::rngs::SmallRng::from_entropy(); + for _ in 0..N_SAMPLES { + let v = dist.sample(&mut rng); + h.add(v[0].atan2(v[1])).unwrap(); + } + let sum: u64 = h.bins().iter().sum(); + println!("{:?}", h); + for &b in h.bins() { + let p = (b as f64) / (sum as f64); + assert!((p - 1.0 / (N_BINS as f64)).abs() < TOL, "{}", p); + } +}