pub struct Gamma { /* private fields */ }
moved to rand_distr crate
Expand description
The Gamma distribution Gamma(shape, scale)
distribution.
The density function of this distribution is
f(x) = x^(k - 1) * exp(-x / θ) / (Γ(k) * θ^k)
where Γ
is the Gamma function, k
is the shape and θ
is the
scale and both k
and θ
are strictly positive.
The algorithm used is that described by Marsaglia & Tsang 20001,
falling back to directly sampling from an Exponential for shape == 1
, and using the boosting technique described in that paper for
shape < 1
.
George Marsaglia and Wai Wan Tsang. 2000. “A Simple Method for Generating Gamma Variables” ACM Trans. Math. Softw. 26, 3 (September 2000), 363-372. DOI:10.1145/358407.358414 ↩
Implementations
Trait Implementations
sourceimpl Distribution<f64> for Gamma
impl Distribution<f64> for Gamma
sourcefn sample<R>(&self, rng: &mut R) -> f64 where
R: Rng + ?Sized,
fn sample<R>(&self, rng: &mut R) -> f64 where
R: Rng + ?Sized,
Generate a random value of T
, using rng
as the source of randomness.
sourcefn sample_iter<R>(self, rng: R) -> DistIter<Self, R, T>ⓘNotable traits for DistIter<D, R, T>impl<D, R, T> Iterator for DistIter<D, R, T> where
D: Distribution<T>,
R: Rng, type Item = T;
where
R: Rng,
fn sample_iter<R>(self, rng: R) -> DistIter<Self, R, T>ⓘNotable traits for DistIter<D, R, T>impl<D, R, T> Iterator for DistIter<D, R, T> where
D: Distribution<T>,
R: Rng, type Item = T;
where
R: Rng,
D: Distribution<T>,
R: Rng, type Item = T;
Create an iterator that generates random values of T
, using rng
as
the source of randomness. Read more
impl Copy for Gamma
Auto Trait Implementations
impl RefUnwindSafe for Gamma
impl Send for Gamma
impl Sync for Gamma
impl Unpin for Gamma
impl UnwindSafe for Gamma
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
impl<T> Pointable for T
impl<T> Pointable for T
impl<SS, SP> SupersetOf<SS> for SP where
SS: SubsetOf<SP>,
impl<SS, SP> SupersetOf<SS> for SP where
SS: SubsetOf<SP>,
fn to_subset(&self) -> Option<SS>
fn to_subset(&self) -> Option<SS>
The inverse inclusion map: attempts to construct self
from the equivalent element of its
superset. Read more
fn is_in_subset(&self) -> bool
fn is_in_subset(&self) -> bool
Checks if self
is actually part of its subset T
(and can be converted to it).
unsafe fn to_subset_unchecked(&self) -> SS
unsafe fn to_subset_unchecked(&self) -> SS
Use with care! Same as self.to_subset
but without any property checks. Always succeeds.
fn from_subset(element: &SS) -> SP
fn from_subset(element: &SS) -> SP
The inclusion map: converts self
to the equivalent element of its superset.