[][src]Struct rand::distributions::Standard

pub struct Standard;

A generic random value distribution, implemented for many primitive types. Usually generates values with a numerically uniform distribution, and with a range appropriate to the type.

Provided implementations

Assuming the provided Rng is well-behaved, these implementations generate values with the following ranges and distributions:

The Standard distribution also supports generation of the following compound types where all component types are supported:

Custom implementations

The Standard distribution may be implemented for user types as follows:

use rand::Rng;
use rand::distributions::{Distribution, Standard};

struct MyF32 {
    x: f32,
}

impl Distribution<MyF32> for Standard {
    fn sample<R: Rng + ?Sized>(&self, rng: &mut R) -> MyF32 {
        MyF32 { x: rng.gen() }
    }
}

Example usage

use rand::prelude::*;
use rand::distributions::Standard;

let val: f32 = StdRng::from_entropy().sample(Standard);
println!("f32 from [0, 1): {}", val);

Floating point implementation

The floating point implementations for Standard generate a random value in the half-open interval [0, 1), i.e. including 0 but not 1.

All values that can be generated are of the form n * ε/2. For f32 the 23 most significant random bits of a u32 are used and for f64 the 53 most significant bits of a u64 are used. The conversion uses the multiplicative method: (rng.gen::<$uty>() >> N) as $ty * (ε/2).

See also: Open01 which samples from (0, 1), OpenClosed01 which samples from (0, 1] and Rng::gen_range(0, 1) which also samples from [0, 1). Note that Open01 and gen_range (which uses Uniform) use transmute-based methods which yield 1 bit less precision but may perform faster on some architectures (on modern Intel CPUs all methods have approximately equal performance).

Trait Implementations

impl Distribution<f32> for Standard[src]

impl Distribution<f64> for Standard[src]

impl Distribution<Simd<[f32; 2]>> for Standard[src]

impl Distribution<Simd<[f32; 4]>> for Standard[src]

impl Distribution<Simd<[f32; 8]>> for Standard[src]

impl Distribution<Simd<[f32; 16]>> for Standard[src]

impl Distribution<Simd<[f64; 2]>> for Standard[src]

impl Distribution<Simd<[f64; 4]>> for Standard[src]

impl Distribution<Simd<[f64; 8]>> for Standard[src]

impl Distribution<u8> for Standard[src]

impl Distribution<u16> for Standard[src]

impl Distribution<u32> for Standard[src]

impl Distribution<u64> for Standard[src]

impl Distribution<u128> for Standard[src]

impl Distribution<usize> for Standard[src]

impl Distribution<i8> for Standard[src]

impl Distribution<i16> for Standard[src]

impl Distribution<i32> for Standard[src]

impl Distribution<i64> for Standard[src]

impl Distribution<i128> for Standard[src]

impl Distribution<isize> for Standard[src]

impl Distribution<NonZeroU8> for Standard[src]

impl Distribution<NonZeroU16> for Standard[src]

impl Distribution<NonZeroU32> for Standard[src]

impl Distribution<NonZeroU64> for Standard[src]

impl Distribution<NonZeroU128> for Standard[src]

impl Distribution<NonZeroUsize> for Standard[src]

impl Distribution<Simd<[i8; 2]>> for Standard[src]

impl Distribution<Simd<[u8; 2]>> for Standard[src]

impl Distribution<Simd<[i16; 2]>> for Standard[src]

impl Distribution<Simd<[u16; 2]>> for Standard[src]

impl Distribution<Simd<[i8; 4]>> for Standard[src]

impl Distribution<Simd<[u8; 4]>> for Standard[src]

impl Distribution<Simd<[i32; 2]>> for Standard[src]

impl Distribution<Simd<[u32; 2]>> for Standard[src]

impl Distribution<Simd<[i16; 4]>> for Standard[src]

impl Distribution<Simd<[u16; 4]>> for Standard[src]

impl Distribution<Simd<[i8; 8]>> for Standard[src]

impl Distribution<Simd<[u8; 8]>> for Standard[src]

impl Distribution<Simd<[i64; 2]>> for Standard[src]

impl Distribution<Simd<[u64; 2]>> for Standard[src]

impl Distribution<Simd<[i32; 4]>> for Standard[src]

impl Distribution<Simd<[u32; 4]>> for Standard[src]

impl Distribution<Simd<[i16; 8]>> for Standard[src]

impl Distribution<Simd<[u16; 8]>> for Standard[src]

impl Distribution<Simd<[i8; 16]>> for Standard[src]

impl Distribution<Simd<[u8; 16]>> for Standard[src]

impl Distribution<Simd<[i64; 4]>> for Standard[src]

impl Distribution<Simd<[u64; 4]>> for Standard[src]

impl Distribution<Simd<[i32; 8]>> for Standard[src]

impl Distribution<Simd<[u32; 8]>> for Standard[src]

impl Distribution<Simd<[i16; 16]>> for Standard[src]

impl Distribution<Simd<[u16; 16]>> for Standard[src]

impl Distribution<Simd<[i8; 32]>> for Standard[src]

impl Distribution<Simd<[u8; 32]>> for Standard[src]

impl Distribution<Simd<[i64; 8]>> for Standard[src]

impl Distribution<Simd<[u64; 8]>> for Standard[src]

impl Distribution<Simd<[i32; 16]>> for Standard[src]

impl Distribution<Simd<[u32; 16]>> for Standard[src]

impl Distribution<Simd<[i16; 32]>> for Standard[src]

impl Distribution<Simd<[u16; 32]>> for Standard[src]

impl Distribution<Simd<[i8; 64]>> for Standard[src]

impl Distribution<Simd<[u8; 64]>> for Standard[src]

impl Distribution<__m64> for Standard[src]

impl Distribution<__m128i> for Standard[src]

impl Distribution<__m256i> for Standard[src]

impl Distribution<char> for Standard[src]

impl Distribution<bool> for Standard[src]

impl Distribution<()> for Standard[src]

impl<A> Distribution<(A,)> for Standard where
    Standard: Distribution<A>, 
[src]

impl<A, B> Distribution<(A, B)> for Standard where
    Standard: Distribution<A>,
    Standard: Distribution<B>, 
[src]

impl<A, B, C> Distribution<(A, B, C)> for Standard where
    Standard: Distribution<A>,
    Standard: Distribution<B>,
    Standard: Distribution<C>, 
[src]

impl<A, B, C, D> Distribution<(A, B, C, D)> for Standard where
    Standard: Distribution<A>,
    Standard: Distribution<B>,
    Standard: Distribution<C>,
    Standard: Distribution<D>, 
[src]

impl<A, B, C, D, E> Distribution<(A, B, C, D, E)> for Standard where
    Standard: Distribution<A>,
    Standard: Distribution<B>,
    Standard: Distribution<C>,
    Standard: Distribution<D>,
    Standard: Distribution<E>, 
[src]

impl<A, B, C, D, E, F> Distribution<(A, B, C, D, E, F)> for Standard where
    Standard: Distribution<A>,
    Standard: Distribution<B>,
    Standard: Distribution<C>,
    Standard: Distribution<D>,
    Standard: Distribution<E>,
    Standard: Distribution<F>, 
[src]

impl<A, B, C, D, E, F, G> Distribution<(A, B, C, D, E, F, G)> for Standard where
    Standard: Distribution<A>,
    Standard: Distribution<B>,
    Standard: Distribution<C>,
    Standard: Distribution<D>,
    Standard: Distribution<E>,
    Standard: Distribution<F>,
    Standard: Distribution<G>, 
[src]

impl<A, B, C, D, E, F, G, H> Distribution<(A, B, C, D, E, F, G, H)> for Standard where
    Standard: Distribution<A>,
    Standard: Distribution<B>,
    Standard: Distribution<C>,
    Standard: Distribution<D>,
    Standard: Distribution<E>,
    Standard: Distribution<F>,
    Standard: Distribution<G>,
    Standard: Distribution<H>, 
[src]

impl<A, B, C, D, E, F, G, H, I> Distribution<(A, B, C, D, E, F, G, H, I)> for Standard where
    Standard: Distribution<A>,
    Standard: Distribution<B>,
    Standard: Distribution<C>,
    Standard: Distribution<D>,
    Standard: Distribution<E>,
    Standard: Distribution<F>,
    Standard: Distribution<G>,
    Standard: Distribution<H>,
    Standard: Distribution<I>, 
[src]

impl<A, B, C, D, E, F, G, H, I, J> Distribution<(A, B, C, D, E, F, G, H, I, J)> for Standard where
    Standard: Distribution<A>,
    Standard: Distribution<B>,
    Standard: Distribution<C>,
    Standard: Distribution<D>,
    Standard: Distribution<E>,
    Standard: Distribution<F>,
    Standard: Distribution<G>,
    Standard: Distribution<H>,
    Standard: Distribution<I>,
    Standard: Distribution<J>, 
[src]

impl<A, B, C, D, E, F, G, H, I, J, K> Distribution<(A, B, C, D, E, F, G, H, I, J, K)> for Standard where
    Standard: Distribution<A>,
    Standard: Distribution<B>,
    Standard: Distribution<C>,
    Standard: Distribution<D>,
    Standard: Distribution<E>,
    Standard: Distribution<F>,
    Standard: Distribution<G>,
    Standard: Distribution<H>,
    Standard: Distribution<I>,
    Standard: Distribution<J>,
    Standard: Distribution<K>, 
[src]

impl<A, B, C, D, E, F, G, H, I, J, K, L> Distribution<(A, B, C, D, E, F, G, H, I, J, K, L)> for Standard where
    Standard: Distribution<A>,
    Standard: Distribution<B>,
    Standard: Distribution<C>,
    Standard: Distribution<D>,
    Standard: Distribution<E>,
    Standard: Distribution<F>,
    Standard: Distribution<G>,
    Standard: Distribution<H>,
    Standard: Distribution<I>,
    Standard: Distribution<J>,
    Standard: Distribution<K>,
    Standard: Distribution<L>, 
[src]

impl<T> Distribution<[T; 0]> for Standard[src]

impl<T> Distribution<[T; 1]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 2]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 3]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 4]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 5]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 6]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 7]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 8]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 9]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 10]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 11]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 12]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 13]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 14]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 15]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 16]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 17]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 18]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 19]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 20]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 21]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 22]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 23]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 24]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 25]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 26]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 27]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 28]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 29]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 30]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 31]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<[T; 32]> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<Option<T>> for Standard where
    Standard: Distribution<T>, 
[src]

impl<T> Distribution<Wrapping<T>> for Standard where
    Standard: Distribution<T>, 
[src]

impl Clone for Standard[src]

impl Copy for Standard[src]

impl Debug for Standard[src]

Auto Trait Implementations

impl Unpin for Standard

impl Sync for Standard

impl Send for Standard

impl UnwindSafe for Standard

impl RefUnwindSafe for Standard

Blanket Implementations

impl<T> ToOwned for T where
    T: Clone
[src]

type Owned = T

The resulting type after obtaining ownership.

impl<T, U> Into<U> for T where
    U: From<T>, 
[src]

impl<T> From<T> for T[src]

impl<T, U> TryFrom<U> for T where
    U: Into<T>, 
[src]

type Error = Infallible

The type returned in the event of a conversion error.

impl<T, U> TryInto<U> for T where
    U: TryFrom<T>, 
[src]

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.

impl<T> BorrowMut<T> for T where
    T: ?Sized
[src]

impl<T> Borrow<T> for T where
    T: ?Sized
[src]

impl<T> Any for T where
    T: 'static + ?Sized
[src]

impl<T> FromCast<T> for T

impl<T, U> Cast<U> for T where
    U: FromCast<T>, 

impl<T> FromBits<T> for T

impl<T, U> IntoBits<U> for T where
    U: FromBits<T>, 

impl<V, T> VZip<V> for T where
    V: MultiLane<T>,