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

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 should attempt to sample in `[low, high)`

for
`Uniform::new(low, high)`

, i.e., excluding `high`

, but this may be very
difficult. All the primitive integer types satisfy this property, and the
float types normally satisfy it, but rounding may mean `high`

can occur.

# 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>`

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`impl<X: SampleUniform> Uniform<X>`

`pub fn new(low: X, high: X) -> Uniform<X>` | [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(low: X, high: X) -> Uniform<X>` | [src] |

Create a new `Uniform`

instance which samples uniformly from the closed
range `[low, high]`

(inclusive). Panics if `low > high`

.

## Trait Implementations

`impl<T: SampleRange> Sample<T> for Range<T>`

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`impl<T: SampleRange> Sample<T> for Range<T>`

`impl<T: SampleRange> IndependentSample<T> for Range<T>`

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`impl<T: SampleRange> IndependentSample<T> for Range<T>`

`fn ind_sample<R: Rng>(&self, rng: &mut R) -> T` | [src] |

`impl<X: SampleUniform> Distribution<X> for Uniform<X>`

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`impl<X: SampleUniform> Distribution<X> for Uniform<X>`

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

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

`fn sample_iter<'a, R>(&'a self, rng: &'a mut R) -> DistIter<'a, Self, R, T> where` | [src] |

Create an iterator that generates random values of `T`

, using `rng`

as the source of randomness. Read more

`impl<X: SampleUniform> From<Range<X>> for Uniform<X>`

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`impl<X: SampleUniform> From<Range<X>> for Uniform<X>`

`impl<X: Copy + SampleUniform> Copy for Uniform<X> where`

X::Sampler: Copy,

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`impl<X: Copy + SampleUniform> Copy for Uniform<X> where`

X::Sampler: Copy,

`impl<X: Clone + SampleUniform> Clone for Uniform<X> where`

X::Sampler: Clone,

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`impl<X: Clone + SampleUniform> Clone for Uniform<X> where`

X::Sampler: Clone,

`fn clone(&self) -> Uniform<X>` | [src] |

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

Performs copy-assignment from `source`

. Read more

`impl<X: Debug + SampleUniform> Debug for Uniform<X> where`

X::Sampler: Debug,

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`impl<X: Debug + SampleUniform> Debug for Uniform<X> where`

X::Sampler: Debug,

## Auto Trait Implementations

`impl<X> Send for Uniform<X> where`

<X as SampleUniform>::Sampler: Send,

`impl<X> Send for Uniform<X> where`

<X as SampleUniform>::Sampler: Send,

`impl<X> Sync for Uniform<X> where`

<X as SampleUniform>::Sampler: Sync,

`impl<X> Sync for Uniform<X> where`

<X as SampleUniform>::Sampler: Sync,

## Blanket Implementations

`impl<T> From for T`

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`impl<T> From for T`

`impl<T, U> Into for T where`

U: From<T>,

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`impl<T, U> Into for T where`

U: From<T>,

`impl<T> ToOwned for T where`

T: Clone,

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`impl<T> ToOwned for T where`

T: Clone,

`impl<T, U> TryFrom for T where`

T: From<U>,

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`impl<T, U> TryFrom for T where`

T: From<U>,

`type Error = !`

`try_from`

)The type returned in the event of a conversion error.

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

`impl<T> Borrow for T where`

T: ?Sized,

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`impl<T> Borrow for T where`

T: ?Sized,

`impl<T> BorrowMut for T where`

T: ?Sized,

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`impl<T> BorrowMut for T where`

T: ?Sized,

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

`impl<T, U> TryInto for T where`

U: TryFrom<T>,

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`impl<T, U> TryInto for T where`

U: TryFrom<T>,

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

`try_from`

)The type returned in the event of a conversion error.

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

`impl<T> Any for T where`

T: 'static + ?Sized,

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`impl<T> Any for T where`

T: 'static + ?Sized,

`fn get_type_id(&self) -> TypeId` | [src] |