# [−][src]Struct rand::distributions::Uniform

    pub struct Uniform<X: SampleUniform> { /* fields omitted */ }

Sample values uniformly between two bounds.

[`Uniform::new`] and [`Uniform::new_inclusive`] construct a uniform distribution sampling from the given range; these functions may do extra work up front to make sampling of multiple values faster.

When sampling from a constant range, many calculations can happen at compile-time and all methods should be fast; for floating-point ranges and the full range of integer types this should have comparable performance to the `Standard` distribution.

Steps are taken to avoid bias which might be present in naive implementations; for example `rng.gen::<u8>() % 170` samples from the range `[0, 169]` but is twice as likely to select numbers less than 85 than other values. Further, the implementations here give more weight to the high-bits generated by the RNG than the low bits, since with some RNGs the low-bits are of lower quality than the high bits.

Implementations must sample in `[low, high)` range for `Uniform::new(low, high)`, i.e., excluding `high`. In particular care must be taken to ensure that rounding never results values `< low` or `>= high`.

# Example

    use rand::distributions::{Distribution, Uniform};

    fn main() {
        let between = Uniform::from(10..10000);
        let mut rng = rand::thread_rng();
        let mut sum = 0;
        for _ in 0..1000 {
            sum += between.sample(&mut rng);
        }
        println!("{}", sum);
    }

## Methods

### `impl<X: SampleUniform> Uniform<X>`[src]

#### `pub fn new<B1, B2>(low: B1, high: B2) -> Uniform<X> where
B1: SampleBorrow<X> + Sized,
B2: SampleBorrow<X> + Sized,` [src]

Create a new `Uniform` instance which samples uniformly from the half open range `[low, high)` (excluding `high`). Panics if `low >= high`.

#### `pub fn new_inclusive<B1, B2>(low: B1, high: B2) -> Uniform<X> where
B1: SampleBorrow<X> + Sized,
B2: SampleBorrow<X> + Sized,` [src]

Create a new `Uniform` instance which samples uniformly from the closed range `[low, high]` (inclusive). Panics if `low > high`.

## Trait Implementations

### `impl<X: SampleUniform> Distribution<X> for Uniform<X>`[src]

#### `fn sample<R: Rng + ?Sized>(&self, rng: &mut R) -> X`[src]

Generate a random value of `T`, using `rng` as the source of randomness.

####
ⓘ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, R>(&'a self, rng: &'a mut R) -> DistIter<'a, Self, R, T> where
Self: Sized,
R: Rng,` [src]

Create an iterator that generates random values of `T`, using `rng` as the source of randomness. Read more

### `impl<X: Clone + SampleUniform> Clone for Uniform<X> where
X::Sampler: Clone,` [src]

#### `fn clone(&self) -> Uniform<X>`[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<X: SampleUniform> From<Range<X>> for Uniform<X>`[src]

#### `fn from(r: Range<X>) -> Uniform<X>`[src]

Performs the conversion.

### `impl<X: SampleUniform> From<RangeInclusive<X>> for Uniform<X>`[src]

#### `fn from(r: RangeInclusive<X>) -> Uniform<X>`[src]

Performs the conversion.

### `impl<X: Copy + SampleUniform> Copy for Uniform<X> where
X::Sampler: Copy,` [src]

### `impl<X: Debug + SampleUniform> Debug for Uniform<X> where
X::Sampler: Debug,` [src]

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

Formats the value using the given formatter. Read more

## Auto Trait Implementations

### `impl<X> Send for Uniform<X> where
<X as SampleUniform>::Sampler: Send,`

### `impl<X> Unpin for Uniform<X> where
<X as SampleUniform>::Sampler: Unpin,`

### `impl<X> Sync for Uniform<X> where
<X as SampleUniform>::Sampler: Sync,`

### `impl<X> UnwindSafe for Uniform<X> where
<X as SampleUniform>::Sampler: UnwindSafe,`

### `impl<X> RefUnwindSafe for Uniform<X> where
<X as SampleUniform>::Sampler: RefUnwindSafe,`

## Blanket Implementations

### `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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