# [−][src]Struct rand::rngs::StdRng

    pub struct StdRng(_);

The standard RNG. The PRNG algorithm in `StdRng` is chosen to be efficient on the current platform, to be statistically strong and unpredictable (meaning a cryptographically secure PRNG).

The current algorithm used on all platforms is HC-128, found in the rand_hc crate.

Reproducibility of output from this generator is however not required, thus future library versions may use a different internal generator with different output. Further, this generator may not be portable and can produce different output depending on the architecture. If you require reproducible output, use a named RNG, for example `ChaChaRng` from the rand_chacha crate.

## Trait Implementations

### `impl Clone for StdRng`[src]

#### `fn clone(&self) -> StdRng`[src]

Returns a copy of the value. Read more

#### `fn clone_from(&mut self, source: &Self)`1.0.0[src]

Performs copy-assignment from `source`. Read more

### `impl Debug for StdRng`[src]

#### `fn fmt(&self, f: &mut Formatter) -> Result`[src]

Formats the value using the given formatter. Read more

### `impl CryptoRng for StdRng`[src]

### `impl RngCore for StdRng`[src]

#### `fn next_u32(&mut self) -> u32`[src]

Return the next random `u32`. Read more

#### `fn next_u64(&mut self) -> u64`[src]

Return the next random `u64`. Read more

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

Fill `dest` with random data. Read more

#### `fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error>`[src]

Fill `dest` entirely with random data. Read more

### `impl SeedableRng for StdRng`[src]

#### `type Seed = <Hc128Rng as SeedableRng>::Seed`

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

#### `fn from_seed(seed: Self::Seed) -> Self`[src]

Create a new PRNG using the given seed. Read more

#### `fn from_rng<R: RngCore>(rng: R) -> Result<Self, Error>`[src]

Create a new PRNG seeded from another `Rng`. Read more

#### `fn seed_from_u64(state: u64) -> Self`[src]

Create a new PRNG using a `u64` seed. Read more

## Auto Trait Implementations

### `impl Send for StdRng`

### `impl Unpin for StdRng`

### `impl Sync for StdRng`

### `impl UnwindSafe for StdRng`

### `impl RefUnwindSafe for StdRng`

## Blanket Implementations

### `impl<R> Rng for R where
R: RngCore + ?Sized,` [src]

#### `fn gen<T>(&mut self) -> T where
Standard: Distribution<T>,` [src]

Return a random value supporting the [`Standard`] distribution. Read more

#### `fn gen_range<T: SampleUniform, B1, B2>(&mut self, low: B1, high: B2) -> T where
B1: SampleBorrow<T> + Sized,
B2: SampleBorrow<T> + Sized,` [src]

Generate a random value in the range [`low`, `high`), i.e. inclusive of `low` and exclusive of `high`. Read more

#### `fn sample<T, D: Distribution<T>>(&mut self, distr: D) -> T`[src]

Sample a new value, using the given distribution. Read more

####
ⓘImportant traits for DistIter<'a, D, R, T>

### Important traits for DistIter<'a, D, R, T>

`impl<'a, D, R, T> Iterator for DistIter<'a, D, R, T> where
D: Distribution<T>,
R: Rng + 'a, type Item = T;`
`fn sample_iter<'a, T, D: Distribution<T>>(
&'a mut self,
distr: &'a D
) -> DistIter<'a, D, Self, T> where
Self: Sized,` [src]

Create an iterator that generates values using the given distribution. Read more

#### `fn fill<T: AsByteSliceMut + ?Sized>(&mut self, dest: &mut T)`[src]

Fill `dest` entirely with random bytes (uniform value distribution), where `dest` is any type supporting [`AsByteSliceMut`], namely slices and arrays over primitive integer types (`i8`, `i16`, `u32`, etc.). Read more

#### `fn try_fill<T: AsByteSliceMut + ?Sized>(
&mut self,
dest: &mut T
) -> Result<(), Error>`[src]

Fill `dest` entirely with random bytes (uniform value distribution), where `dest` is any type supporting [`AsByteSliceMut`], namely slices and arrays over primitive integer types (`i8`, `i16`, `u32`, etc.). Read more

#### `fn gen_bool(&mut self, p: f64) -> bool`[src]

Return a bool with a probability `p` of being true. Read more

#### `fn gen_ratio(&mut self, numerator: u32, denominator: u32) -> bool`[src]

Return a bool with a probability of `numerator/denominator` of being true. I.e. `gen_ratio(2, 3)` has chance of 2 in 3, or about 67%, of returning true. If `numerator == denominator`, then the returned value is guaranteed to be `true`. If `numerator == 0`, then the returned value is guaranteed to be `false`. Read more

#### `fn choose<'a, T>(&mut self, values: &'a [T]) -> Option<&'a T>`[src]

Deprecated since 0.6.0:

use SliceRandom::choose instead

Return a random element from `values`. Read more

#### `fn choose_mut<'a, T>(&mut self, values: &'a mut [T]) -> Option<&'a mut T>`[src]

Deprecated since 0.6.0:

use SliceRandom::choose_mut instead

Return a mutable pointer to a random element from `values`. Read more

#### `fn shuffle<T>(&mut self, values: &mut [T])`[src]

Deprecated since 0.6.0:

use SliceRandom::shuffle instead

Shuffle a mutable slice in place. Read more

### `impl<R> FromEntropy for R where
R: SeedableRng,` [src]

#### `fn from_entropy() -> R`[src]

Creates a new instance, automatically seeded with fresh entropy. Read more

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

#### `type Owned = T`

The resulting type after obtaining ownership.

#### `fn to_owned(&self) -> T`[src]

Creates owned data from borrowed data, usually by cloning. Read more

#### `fn clone_into(&self, target: &mut T)`[src]

🔬 This is a nightly-only experimental API. (`toowned_clone_into`)

recently added

Uses borrowed data to replace owned data, usually by cloning. Read more

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

#### `fn into(self) -> U`[src]

Performs the conversion.

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

#### `fn from(t: T) -> T`[src]

Performs the conversion.

### `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.

#### `fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>`[src]

Performs the conversion.

### `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.

#### `fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>`[src]

Performs the conversion.

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

#### `fn borrow_mut(&mut self) -> &mut T`[src]

Mutably borrows from an owned value. Read more

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

#### `fn borrow(&self) -> &T`[src]

Immutably borrows from an owned value. Read more

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

#### `fn type_id(&self) -> TypeId`[src]

Gets the `TypeId` of `self`. Read more

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