pub struct Poisson { /* private fields */ }
Expand description
Implements the Poisson
distribution
use statrs::distribution::{Poisson, Discrete};
use statrs::statistics::Distribution;
use statrs::prec;
let n = Poisson::new(1.0).unwrap();
assert_eq!(n.mean().unwrap(), 1.0);
assert!(prec::almost_eq(n.pmf(1), 0.367879441171442, 1e-15));
Constructs a new poisson distribution with a rate (λ)
of lambda
Returns an error if lambda is NaN or lambda <= 0.0
use statrs::distribution::Poisson;
let mut result = Poisson::new(1.0);
assert!(result.is_ok());
result = Poisson::new(0.0);
assert!(result.is_err());
Returns the rate (λ) of the poisson distribution
use statrs::distribution::Poisson;
let n = Poisson::new(1.0).unwrap();
assert_eq!(n.lambda(), 1.0);
Performs copy-assignment from source. Read more
Formats the value using the given formatter. Read more
Calculates the probability mass function for the poisson distribution at
x
where λ is the rate
Calculates the log probability mass function for the poisson
distribution at
x
where λ is the rate
Calculates the cumulative distribution function for the poisson
distribution at x
where λ is the rate and P is the lower regularized gamma function
Due to issues with rounding and floating-point accuracy the default implementation may be ill-behaved
Specialized inverse cdfs should be used whenever possible. Read more
Generates one sample from the Poisson distribution either by
Knuth’s method if lambda < 30.0 or Rejection method PA by
A. C. Atkinson from the Journal of the Royal Statistical Society
Series C (Applied Statistics) Vol. 28 No. 1. (1979) pp. 29 - 35
otherwise
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
Returns the mean of the poisson distribution
where λ is the rate
Returns the variance of the poisson distribution
where λ is the rate
Returns the entropy of the poisson distribution
(1 / 2) * ln(2πeλ) - 1 / (12λ) - 1 / (24λ^2) - 19 / (360λ^3)
where λ is the rate
Returns the skewness of the poisson distribution
where λ is the rate
Returns the standard deviation, if it exists. Read more
Returns the maximum value in the domain of the poisson distribution
representable by a 64-bit integer
Returns the median of the poisson distribution
floor(λ + 1 / 3 - 0.02 / λ)
where λ is the rate
Returns the minimum value in the domain of the poisson distribution
representable by a 64-bit integer
Returns the mode of the poisson distribution
where λ is the rate
This method tests for self and other values to be equal, and is used
by ==. Read more
This method tests for !=.
impl<T> Any for T where
T: 'static + ?Sized,
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more
impl<T, U> Into<U> for T where
U: From<T>,
Performance hack: Clone doesn’t get inlined for Copy types in debug mode, so make it inline anyway.
Tests if Self the same as the type T Read more
The inverse inclusion map: attempts to construct self from the equivalent element of its
superset. Read more
Checks if self is actually part of its subset T (and can be converted to it).
Use with care! Same as self.to_subset but without any property checks. Always succeeds.
The inclusion map: converts self to the equivalent element of its superset.
The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
🔬 This is a nightly-only experimental API. (toowned_clone_into)
Uses borrowed data to replace owned data, usually by cloning. Read more
The type returned in the event of a conversion error.
The type returned in the event of a conversion error.
