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//! This crate aims to be a functional port of the Math.NET Numerics
//! Distribution package and in doing so providing the Rust numerical computing
//! community with a robust, well-tested statistical distribution package. This
//! crate also ports over some of the special statistical functions from
//! Math.NET in so far as they are used in the computation of distribution
//! values. This crate depends on the `rand` crate to provide RNG.
//!
//! # Sampling
//! The common use case is to set up the distributions and sample from them which depends on the `Rand` crate for random number generation.
//! use statrs::distribution::Exp;
//! use rand::distr::Distribution;
//! use rand::SeedableRng;
//! let mut r = rand::rngs::StdRng::seed_from_u64(0);
//! let n = Exp::new(0.5).unwrap();
//! print!("{}", n.sample(&mut r));
//! ```
//!
//! # Introspecting distributions
//! Statrs also comes with a number of useful utility traits for more detailed introspection of distributions.
//! ```
//! use statrs::distribution::{Exp, Continuous, ContinuousCDF}; // `cdf` and `pdf`
//! use statrs::statistics::Distribution; // statistical moments and entropy
//!
//! let n = Exp::new(1.0).unwrap();
//! assert_eq!(n.mean(), Some(1.0));
//! assert_eq!(n.variance(), Some(1.0));
//! assert_eq!(n.entropy(), Some(1.0));
//! assert_eq!(n.skewness(), Some(2.0));
//! assert_eq!(n.cdf(1.0), 0.6321205588285576784045);
//! assert_eq!(n.pdf(1.0), 0.3678794411714423215955);
//! ```
//!
//! # Utility functions
//! as well as utility functions including `erf`, `gamma`, `ln_gamma`, `beta`, etc.
//!
//! ```
//! use statrs::distribution::FisherSnedecor;
//! use statrs::statistics::Distribution;
//!
//! let n = FisherSnedecor::new(1.0, 1.0).unwrap();
//! assert!(n.variance().is_none());
//! ```
//! ## Distributions implemented
//! Statrs comes with a number of commonly used distributions including Normal, Gamma, Student's T, Exponential, Weibull, etc. view all implemented in `distributions` module.