# Struct rand::distributions::Bernoulli

``pub struct Bernoulli { /* private fields */ }``
Expand description

The Bernoulli distribution.

This is a special case of the Binomial distribution where `n = 1`.

## Example

``````use rand::distributions::{Bernoulli, Distribution};

let d = Bernoulli::new(0.3).unwrap();
let v = d.sample(&mut rand::thread_rng());
println!("{} is from a Bernoulli distribution", v);``````

## Precision

This `Bernoulli` distribution uses 64 bits from the RNG (a `u64`), so only probabilities that are multiples of 2-64 can be represented.

## Implementations

Construct a new `Bernoulli` with the given probability of success `p`.

##### Precision

For `p = 1.0`, the resulting distribution will always generate true. For `p = 0.0`, the resulting distribution will always generate false.

This method is accurate for any input `p` in the range `[0, 1]` which is a multiple of 2-64. (Note that not all multiples of 2-64 in `[0, 1]` can be represented as a `f64`.)

Construct a new `Bernoulli` with the probability of success of `numerator`-in-`denominator`. I.e. `new_ratio(2, 3)` will return a `Bernoulli` with a 2-in-3 chance, or about 67%, of returning `true`.

return `true`. If `numerator == 0` it will always return `false`. For `numerator > denominator` and `denominator == 0`, this returns an error. Otherwise, for `numerator == denominator`, samples are always true; for `numerator == 0` samples are always false.

## Trait Implementations

Returns a copy of the value. Read more
Performs copy-assignment from `source`. Read more
Formats the value using the given formatter. Read more
Generate a random value of `T`, using `rng` as the source of randomness.
Create an iterator that generates random values of `T`, using `rng` as the source of randomness. Read more
Create a distribution of values of ‘S’ by mapping the output of `Self` through the closure `F` Read more
This method tests for `self` and `other` values to be equal, and is used by `==`. Read more
This method tests for `!=`. The default implementation is almost always sufficient, and should not be overridden without very good reason. Read more

## Blanket Implementations

Gets the `TypeId` of `self`. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls `U::from(self)`.

That is, this conversion is whatever the implementation of `From<T> for U` chooses to do.

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