aboutsummaryrefslogtreecommitdiff
path: root/rand/rand_xoshiro/src/xoshiro128starstar.rs
diff options
context:
space:
mode:
Diffstat (limited to 'rand/rand_xoshiro/src/xoshiro128starstar.rs')
-rw-r--r--rand/rand_xoshiro/src/xoshiro128starstar.rs111
1 files changed, 0 insertions, 111 deletions
diff --git a/rand/rand_xoshiro/src/xoshiro128starstar.rs b/rand/rand_xoshiro/src/xoshiro128starstar.rs
deleted file mode 100644
index 7af1e50..0000000
--- a/rand/rand_xoshiro/src/xoshiro128starstar.rs
+++ /dev/null
@@ -1,111 +0,0 @@
-// Copyright 2018 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.
-
-#[cfg(feature="serde1")] use serde::{Serialize, Deserialize};
-use rand_core::impls::{next_u64_via_u32, fill_bytes_via_next};
-use rand_core::le::read_u32_into;
-use rand_core::{SeedableRng, RngCore, Error};
-
-/// A xoshiro128** random number generator.
-///
-/// The xoshiro128** algorithm is not suitable for cryptographic purposes, but
-/// is very fast and has excellent statistical properties.
-///
-/// The algorithm used here is translated from [the `xoshiro128starstar.c`
-/// reference source code](http://xoshiro.di.unimi.it/xoshiro128starstar.c) by
-/// David Blackman and Sebastiano Vigna.
-#[derive(Debug, Clone)]
-#[cfg_attr(feature="serde1", derive(Serialize, Deserialize))]
-pub struct Xoshiro128StarStar {
- s: [u32; 4],
-}
-
-impl Xoshiro128StarStar {
- /// Jump forward, equivalently to 2^64 calls to `next_u32()`.
- ///
- /// This can be used to generate 2^64 non-overlapping subsequences for
- /// parallel computations.
- ///
- /// ```
- /// use rand_xoshiro::rand_core::SeedableRng;
- /// use rand_xoshiro::Xoroshiro128StarStar;
- ///
- /// let rng1 = Xoroshiro128StarStar::seed_from_u64(0);
- /// let mut rng2 = rng1.clone();
- /// rng2.jump();
- /// let mut rng3 = rng2.clone();
- /// rng3.jump();
- /// ```
- pub fn jump(&mut self) {
- impl_jump!(u32, self, [0x8764000b, 0xf542d2d3, 0x6fa035c3, 0x77f2db5b]);
- }
-}
-
-impl SeedableRng for Xoshiro128StarStar {
- type Seed = [u8; 16];
-
- /// Create a new `Xoshiro128StarStar`. If `seed` is entirely 0, it will be
- /// mapped to a different seed.
- #[inline]
- fn from_seed(seed: [u8; 16]) -> Xoshiro128StarStar {
- deal_with_zero_seed!(seed, Self);
- let mut state = [0; 4];
- read_u32_into(&seed, &mut state);
- Xoshiro128StarStar { s: state }
- }
-
- /// Seed a `Xoshiro128StarStar` from a `u64` using `SplitMix64`.
- fn seed_from_u64(seed: u64) -> Xoshiro128StarStar {
- from_splitmix!(seed)
- }
-}
-
-impl RngCore for Xoshiro128StarStar {
- #[inline]
- fn next_u32(&mut self) -> u32 {
- let result_starstar = starstar_u64!(self.s[0]);
- impl_xoshiro_u32!(self);
- result_starstar
- }
-
- #[inline]
- fn next_u64(&mut self) -> u64 {
- next_u64_via_u32(self)
- }
-
- #[inline]
- fn fill_bytes(&mut self, dest: &mut [u8]) {
- fill_bytes_via_next(self, dest);
- }
-
- #[inline]
- fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
- self.fill_bytes(dest);
- Ok(())
- }
-}
-
-#[cfg(test)]
-mod tests {
- use super::*;
-
- #[test]
- fn reference() {
- let mut rng = Xoshiro128StarStar::from_seed(
- [1, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 4, 0, 0, 0]);
- // These values were produced with the reference implementation:
- // http://xoshiro.di.unimi.it/xoshiro128starstar.c
- let expected = [
- 5760, 40320, 70819200, 3297914139, 2480851620, 1792823698,
- 4118739149, 1251203317, 1581886583, 1721184582,
- ];
- for &e in &expected {
- assert_eq!(rng.next_u32(), e);
- }
- }
-}