Struct Xoroshiro128pp

pub struct Xoroshiro128pp(/* private fields */);

Available on crate feature rand only.

The Xoroshiro128++ PRNG.

It has a 128-bit state and generates 32-bit numbers.

Implementations

impl Xoroshiro128pp

Constructors

pub const fn new(seed: [u32; 4]) -> Option<Self>

Creates a new Xoroshiro128++ PRNG with the given seed.

Returns None if the seed parts are all zero.

pub const fn new_unchecked(seed: [u32; 4]) -> Self

Creates a new Xoroshiro128++ PRNG with the given seed without any checks.

Panics

Panics in debug mode if the seed parts are all 0.

pub fn from_stack() -> Self

Creates a new Xoroshiro128++ PRNG, seeded from addresses of stack variables.

This is a very poor source of randomness.

pub fn from_heap() -> Self

Creates a new Xoroshiro128++ PRNG, seeded from addresses of heap and stack variables.

This is a very poor source of randomness.

pub fn from_randomstate() -> Self

Creates a new Xoroshiro128++ PRNG, seeded from RandomState.

pub const fn inner_state(self) -> [u32; 4]

Returns the PRNG’s inner state as a raw snapshot.

pub const fn from_state(state: [u32; 4]) -> Self

Restores the PRNG from the given state.

impl Xoroshiro128pp

Methods taking &mut self

pub fn jump(&mut self)

The jump function for the generator, equivalent to 2^64 next_u32 calls.

pub fn long_jump(&mut self)

The long jump function for the generator, equivalent to 2^96 next_u32 calls.

pub fn next_u32(&mut self) -> u32

Generates the next random u32 value.

pub fn next2(&mut self) -> [u32; 2]

Generates the next 2 random u32 values.

pub fn next4(&mut self) -> [u32; 4]

Generates the next 4 random u32 values.

pub fn next4_u8(&mut self) -> [u8; 4]

Generates the next random value split into 4 u8 values.

pub fn next2_u16(&mut self) -> [u16; 2]

Available on crate feature split only.

Generates the next random value split into 2 u16 values.

pub fn next_u64(&mut self) -> u64

Available on crate feature join only.

Returns the next u64, advancing the state 2 times.

pub fn next_u128(&mut self) -> u128

Available on crate feature join only.

Returns the next u128, advancing the state 4 times.

impl Xoroshiro128pp

Methods taking self

pub const fn current_u32(self) -> u32

Returns the current random u32, without updating the state.

pub const fn copy_peek_next_state(self) -> Self

Returns a copy of the next new random state.

pub const fn own_next_u32(self) -> Own<Self, u32>

Returns both the next random state and the u32 value in a tuple.

pub const fn copy_jump(self) -> Self

Returns a copy of the state jumped ahead by 2^64 steps.

pub const fn copy_long_jump(self) -> Self

Returns a copy of the state long-jumped ahead by 2^96 steps.

impl Xoroshiro128pp

Extra constructors

pub const fn new1_u128(seed: u128) -> Option<Self>

Available on crate feature split only.

Returns a seeded Xoroshiro128pp generator from the given 128-bit seed.

The seeds will be split in little endian order.

pub const fn new2_u64(seeds: [u64; 2]) -> Option<Self>

Available on crate feature split only.

Returns a seeded Xoroshiro128pp generator from the given 2 × 64-bit seeds.

The seeds will be split in little endian order.

pub const fn new4_u32(seeds: [u32; 4]) -> Option<Self>

Returns a seeded Xoroshiro128pp generator from the given 4 × 32-bit seeds.

This is an alias of new.

pub const fn new8_u16(seeds: [u16; 8]) -> Option<Self>

Available on crate feature join only.

Returns a seeded Xoroshiro128pp generator from the given 8 × 16-bit seeds.

The seeds will be joined in little endian order.

pub const fn new16_u8(seeds: [u8; 16]) -> Option<Self>

Returns a seeded Xoroshiro128pp generator from the given 16 × 8-bit seeds.

The seeds will be joined in little endian order.

Trait Implementations

impl Clone for Xoroshiro128pp

fn clone(&self) -> Xoroshiro128pp

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl ConstDefault for Xoroshiro128pp

Creates a new PRNG initialized with the default fixed seed.

const DEFAULT: Self

Returns the compile-time “default value” for a type.

impl Debug for Xoroshiro128pp

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Xoroshiro128pp

Creates a new PRNG initialized with the default fixed seed.

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq for Xoroshiro128pp

fn eq(&self, other: &Xoroshiro128pp) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl RngCore for Xoroshiro128pp

Available on crate feature dep_rand_core only.

fn next_u32(&mut self) -> u32

Returns the next random u32.

fn next_u64(&mut self) -> u64

Returns the next random u64.

fn fill_bytes(&mut self, dest: &mut [u8])

Fill dest with random data.

impl SeedableRng for Xoroshiro128pp

Available on crate feature dep_rand_core only.

fn from_seed(seed: Self::Seed) -> Self

When seeded with zero this implementation uses the default seed value as the cold path.

type Seed = [u8; 16]

Seed type, which is restricted to types mutably-dereferenceable as u8 arrays (we recommend [u8; N] for some N).

fn seed_from_u64(state: u64) -> Self

Create a new PRNG using a u64 seed.

fn from_rng(rng: &mut impl RngCore) -> Self

Create a new PRNG seeded from an infallible Rng.

fn try_from_rng<R>(rng: &mut R) -> Result<Self, <R as TryRngCore>::Error>

where R: TryRngCore,

Create a new PRNG seeded from a potentially fallible Rng.

impl Copy for Xoroshiro128pp

impl Eq for Xoroshiro128pp

impl StructuralPartialEq for Xoroshiro128pp